By Leo Procopio, Paintology Coatings Research LLC

The United States has the most extensive road infrastructure in the world, with more than 4.1 million miles of public roads (of which about 2.8 million miles are paved.) ��From small rural roads to large urban highways, these roadways are heavily traveled, with about 3 trillion miles covered by vehicles annually.¹ And with approximately 40,000 annual traffic deaths, traffic safety is always a high priority.�� Traffic safety professionals employ a variety of traffic control devices to make our roads as safe as possible, including signs, signals, and road markings. The Manual on Uniform Traffic Control Devices for Streets and Highways (MUTCD), issued by the Federal Highway Administration (FHWA), defines standards for the installation and maintenance of traffic signs, signals, and road markings on roads open to public traffic.²

Road markings are key elements of road surfaces and provide drivers with essential information to aid in navigation and make their journey safer. Key information such as lane demarcation, indication of passing zones, and the highlighting of safety awareness zones (e.g., schools, crosswalks, and bicycle lanes) is communicated to drivers via road markings. Paint and coating technology plays a significant role in the manufacture of road markings. The coating technologies are also utilized in adjacent applications such as pavement markings for parking lots and airfields.

Traffic paints and road markings are dominated by two technologies – waterborne paints and hot melt thermoplastics. The overall U.S. market for traffic paints was recently estimated to be approximately 10% by value of the Special Purpose Coatings segment for the year 2023, or about $710 million.³ Another study placed the value of the U.S. traffic paint market, excluding hot melt thermoplastics, at approximately 52 million gallons and $650 million for 2015.⁴

The market is large and growing, and raw material manufacturers and coatings suppliers are constantly innovating to meet the performance demands of the industry. This article will discuss some of the science behind road markings. A roundtable Q&A, in which we ask several experts for their thoughts on where the industry is today, trends, challenges, new developments, the role of sustainability, and what to expect in the future, appears here.

Types of road markings

Waterborne coatings based on acrylic latex polymers are the most common type of traffic paint used today. Prior to the 1990s, solventborne chlorinated rubber and alkyd coatings were very commonly used to paint road lines because of their fast dry times; however, due to VOC regulations, waterborne coatings now dominate. Acrylics generally have good weathering resistance and durability, as well as adhesion on the asphalt and concrete surfaces found on roadways. Advances made in the 1990s led to fast setting acrylic latex coatings with greatly enhanced dry times.⁵ Fast dry times are important when striping roads in order to minimize lane closure times, as well as to prevent the tracking of wet paint across the road surface if lines are run over by tires shortly after application.

When better film toughness and longer service life is desired, multi-component liquid coatings relying on highly crosslinked films can be utilized. Examples include two-component (2k) epoxies and polyureas that have excellent adhesion to the road surface and have better resistance to wear and abrasion.

Another high-solids solution for road markings are methyl methacrylate (MMA) coatings, also referred to as cold plastic. These 100% solids liquid coatings consist of acrylic monomers and oligomers which are mixed with a peroxide initiator just prior to application. After application to the road, a polymerization reaction rapidly occurs, resulting in a fully cured coating. These crosslinked coatings are less common than waterborne coatings due to their higher cost, but they can provide higher performance when needed.

In addition to waterborne acrylic traffic paints, another common road marking technology is hot melt thermoplastics. Thermoplastic road marking materials are 100% solids materials supplied in solid form and are typically based on a petroleum-based hydrocarbon resin or a rosin derivative along with optional plasticizers. The coatings are heated above their softening point, typically above 200°C, and applied by spray or extrusion to the road while hot. Once cooled, they solidify again, allowing the road to be returned to service quickly. Even though the low molecular weight resins don’t impart excellent wear resistance to the final coatings, thermoplastics are applied in thick layers (2 or 3 mm), which leads to long service life for this technology. Thermoplastic can also be pre-formed into designs such as letters or arrows, which can then be easily positioned on the road and melted in place with a torch.

Retroreflectivity and other key properties

As with any coating, traffic paints have a number of important properties that must be met to insure excellent performance in the field. To remain functional, lines and other markings must be visible to drivers. Film properties like adhesion and resistance to wear and abrasion (e.g., from tires or snowplows) are required to guarantee the line remains on the road surface. Color and contrast with the road surface also have an impact on visibility, especially during the daytime, and for this reason white and yellow are the favored colors.

FIGURE 1. Traffic paint film with glass beads protruding from the surface.

Nighttime visibility, however, relies on the principle of retroreflectivity. To be easily seen at night, the road marking must reflect light from the headlights back to the driver.�� This is accomplished by incorporating retroreflective glass beads into the road marking. As an example, for liquid traffic paints, glass beads are dropped onto the wet paint immediately after paint application and become embedded into the final film (Figure 1).

For thermoplastic road markings, glass beads can be dropped on the film while still hot but can also be incorporated into the material before application. By incorporating the beads throughout the thermoplastic layer, retroreflectivity is maintained even as the film and beads on top are worn away, because new glass beads will become exposed at the surface.

FIGURE 2. Depiction of retroreflection of light by glass beads embedded in traffic paint film.

Figure 2 shows the process of retroreflectivity for pavement markings. Light from the approaching headlight enters the glass bead, bends, reflects off the paint on the back of the bead, then bends again as it leaves the bead and is directed back to the driver. To function, the glass bead must be partially protruding from the film surface (about 50% is optimal.) Variables such as bead size, refractive index, and weight loading of beads in the film impact the amount of light returned to the driver.

Retroreflectivity can be measured in the laboratory or on installed traffic lines using portable instruments and according to standard methods for dry (ASTM E1710)⁶ or wet (ASTM E2177 and E2832)^7,8 conditions. Retroreflectivity is reported in units of millicandelas per square meter per lux (mcd/m²/lux).

The MUCTD was updated in 2022 to require maintenance of retroreflectivity at a minimum of 100 mcd/m²/lux for longitudinal lines on dry roads with speed limits of 70 mph or higher, with compliance expected by 2026.⁹ It is more difficult, however, to maintain retroreflectivity under wet conditions, particularly if there is a layer of water covering the glass beads. Standard glass beads have a refractive index of 1.5, but don’t perform well when wet because the layer of water, which has a higher refractive index than air, bends the light at a different angle. This results in less light being returned to the driver and lower visibility of the line. Beads with larger diameters and higher refractive indexes have been developed for improved retroreflectivity under wet conditions.

How well a traffic paint retains retroreflectivity over time impacts its service life. Paint films will lose adhesion to glass beads due to tire abrasion and weathering, beads will be removed from the surface, and retroreflectivity will decrease. While retroreflectivity is one measure of how well a traffic paint is holding up, durability is also defined as film loss that exposes the road surface, and is evaluated according to ASTM D 913.¹⁰ Durability is affected by adhesion to the road surface, film toughness, and weathering and abrasion resistance.�� Poor durability leads to loss of color and visibility of the line even in daylight.

One other key property for traffic paints, particularly for liquid coatings such as waterborne acrylics, is dry time. Fast dry times are important to prevent tracking of paint if wet lines are run over by tires, as well as the possibility of wash-out if a rain cloud happens to pass over a freshly painted line. In addition, faster dry times allow less downtime for traffic lanes. In the laboratory, dry time can be evaluated according to ASTM D711, which utilizes a weighted wheel with rubber O-rings.¹¹ Simulating the pressure of a tire on pavement, the wheel is rolled over the coating at various times to determine the drying time needed for no pick-up.

Alternatively, a real-world evaluation can be done in the field according to ASTM D713, where an auto tire is driven over a freshly painted line at various dry times to determine the no-track time.¹² Dry-to-no-pickup times do not necessarily indicate that the paint has wash-out resistance in case of a rain event. Dry-through indicates the point at which a waterborne paint film has enough integrity to resist rain and can be detected by applying a gloved thumb with light pressure and twisting without damage.

Formulating road markings

TABLE 1. Generic White Traffic Paint Formulation Based on a Waterborne Acrylic Latex

For waterborne traffic paints, one way to achieve fast dry times is to remove excess water from the formulation and formulate at high-volume solids. For this reason, waterborne traffic paints are formulated at high pigment volume concentrations (PVC) and using high levels of extenders. Most of the water in the final paint comes from the latex polymer. An example of a generic white traffic paint based on a waterborne acrylic latex polymer is shown in Table 1.

Pigments are dispersed directly into the latex to minimize the amount of extra water. Calcium carbonate is often used as extender pigment due to its low cost, whiteness, and low oil absorption (i.e., easy dispersion at low water demand.) In addition to coalescent needed for film formation, the other main source of VOC in a waterborne traffic paint is from the use of an alcohol such as methanol to optimize freeze thaw resistance and dry-to-no pickup times.

Another way to achieve fast dry times in a waterborne traffic paint is to choose a polymer that utilizes quick-setting technology.⁵ The quick-set mechanism is triggered by a decrease in pH as ammonia leaves the drying paint film. The latex is therefore supplied at high pH (typically above pH 10.0), and the paint formulation is adjusted to maintain a high pH, otherwise poor stability can result in the can. A unique feature of this technology is faster dry-through times compared to conventional waterborne paints, even at higher humidities where water evaporation is slower.

FIGURE 3. Application of green bike lane based on waterborne DURATRACK™ technology. The green paint is first applied by multiple spray guns on the right, followed by application of the glass anti-skid aggregate on the left of the picture. Photograph courtesy of Dow.

For white paints, a minimum of 1 lb/gal of titanium dioxide is typically specified to ensure good opacity.�� Of course, other colors are available, such as yellow for centerlines or green for bike lanes, and may require a mix of inorganic and organic color pigments to achieve the correct shade. An example of a waterborne green bike lane coating being applied is shown in Figure 3.�� Because of the greater width of the bike lane compared to typical road marking lines, several spray heads are used to apply it in a single pass. A glass anti-skid aggregate is applied immediately after the paint is sprayed onto the road surface.

TABLE 2. Generic White Road-Marking Formulation Based on a Thermoplastic Resin

In addition to waterborne traffic paints, hot melt thermoplastic road markings are also commonly used on roads. An example of a generic white thermoplastic formulation is shown in Table 2.¹³ The final formulation is supplied as a solid, either in granular or brick form. Glass beads are mixed into the material during formulation (referred to as intermix), and additional beads could be also dropped onto the surface of the marking immediately after it is applied to the road. The binder is typically either a hydrocarbon resin or rosin derivative, and additionally plasticizers may be employed to prevent brittleness of the applied road marking.

The driving force behind traffic paint formulations are state departments of transportation (DOTs), who are key end-users and ensure paint quality and performance through specifications. Specifications often dictate the specific types and amounts of ingredients for the paint manufacturer to use,¹⁴ as well as expected performance properties.¹⁵

Testing Performance

State DOTs and municipal agencies are typical end-users of road markings and use qualified product lists (QPLs) to signal what products they have found acceptable for use on their roads.�� To be placed on a QPL, the road marking material will undergo testing to prove that it can provide satisfactory performance. Many traffic paints are evaluated through a testing program for pavement marking materials run by the American Association of State Highway and Transportation Officials (AASHTO).

Now known as the AASHTO Product Evaluation and Audit Solutions Program, it was formerly referred to as the National Transportation Product Evaluation Program (NTPEP).

FIGURE 4. Waterborne traffic paint being applied on concrete during a NTPEP transverse test deck application in Wisconsin. Photograph courtesy of BASF.

The AASHTO program involves real-world testing of pavement markings on test decks located across the country, with application of paints supervised by the host state DOT. Suppliers are afforded the opportunity to apply transverse lines (i.e., perpendicular to the flow of traffic) of their materials on asphalt and concrete test decks. Multiple lines of each material are applied. An example of waterborne traffic paints being applied on a test deck in Wisconsin is shown in Figure 4.

Transverse lines are a difficult test environment for road markings because they come into more direct contact with automobile tires compared to longitudinal lines such as edge and center lines. Properties such as color, durability, and retroreflectivity are periodically measured in both the wheel track area (the area where tires most commonly come into contact with the line) and skip area (near the edge line).�� DOTs and other end-users can use the information to make decisions on which products to use on their roads.

The data gathered from the annual test decks are stored online and can be accessed at the AASHTO Product Evaluation and Audit Solutions DataMine website.¹⁶ Data recorded include the environmental conditions during application, physical properties of the paints, the type and loading of glass beads, and wet film thickness (WFT) applied. Both laboratory test results and field performance are also recorded, including retroreflectivity, durability, and color readings out to three years exposure. In addition, photographs of the actual lines are also stored in the online system.

The test decks are valuable because they evaluate multiple products applied at the same time and to the same road surface, and which experience the same exposure conditions, allowing an “apples-to-apples” comparison of performance. An example of the type of data available is shown in Figure 5, which plots retroreflectivity under dry conditions for several waterborne white traffic paints applied to a test deck in Florida in 2019. The road markings were followed for 3 years, with some obvious differentiation in performance. Paint A was observed to have much higher retroreflectivity compared to the other paints over the course of the evaluation. Possible reasons for this include that Paint A was applied at a higher film thickness (30 versus 15 mils WFT), and with a larger grade of glass bead (Type 3 versus Type 1, according to AASHTO M-247)¹⁷ compared to Paints B through E.

Figure 5. Retroreflectivity vs exposure time for waterborne paints exposed on an AASHTO NTPEP test deck in Florida starting in 2019. Note that Paint A was applied at a higher wet film thickness (30 vs 15 mil WFT) and with a different type of glass bead (Type 3 vs Type 1, according to the AASHTO M257 specification17) compared to the other paints. Data selected from the AASHTO Product Evaluation and Audit Solutions Datamine website for Pavement Marking Materials.

Conclusions

��The first documented example of a painted traffic line in the United States is from 1911 in Wayne County, MI. In the more tha 100 years since that first use, the technology and science behind road markings has progressed tremendously. Today’s road markings are highy engineered materials designed for long life, excellent visibility even under adverse conditions, and cost-effectiveness. Our roads are safer because of road markings, and coatings technology has played an important role in getting us to where we are today.

Of course, that is not to imply there is nothing more to achieve for traffic paints. Higher levels of durability and better retention of retroreflectivity lead to longer service lives and are good goals, as is improving retroreflectivity and thus driver visibility under wet conditions. And the interaction between autonomous vehicles (AV) and road markings is an important topic being discussed within the traffic safety community and will be key to the success of AV technology. There is no doubt that coatings science will continue to have a key role in the future development of road markings.

��References

1. “Highway Statistics 2020”, Office of Highway Policy Information, Federal Highway Administration, U.S Department of Transportation, accessed at .
2. “Manual on Uniform Traffic Control Devices for Streets and Highways,” Federal Highway Administration, U.S Department of Transportation, 2009.
3. Pilcher, G., “The State of the U.S. Paint and Coatings Market: More Reliable Supply Chain, Slight Decline in Volume,” CoatingsTech, 20 (5), pp. 50 – 62, Sept/Oct 2023.
4. “The U.S. Paint & Coatings Industry, 2015–2020”, Kusumgar, Nerfli & Growney, 2016.
5. For example, see: Landy, F.; Mercurio, A.; Flynn, R., “Shelf stable fast cure aqueous coating,” US Patent 5,527,823.
6. “Standard Test Method for Measurement of Retroreflective Pavement Marking Materials with CEN-Prescribed Geometry Using a Portable Retroreflectometer,” ASTM E1710, ASTM International, 2018.
7. “Standard Test Method for Measuring the Coefficient of Retroreflected Luminance (RL) of Pavement Markings using the Bucket Method in a Condition of Wet Recovery,” ASTM E2177, ASTM International, 2020.
8. “Standard Test Method for Measuring the Coefficient of Retroreflected Luminance of Pavement Markings in a Standard Condition of Continuous Wetting (RL-2),” ASTM E2832, ASTM International, 2017.
9. “National Standards fro Traffic Control Devices; the Manual on Uniform Traffic Control Devices for Streets and Highways; Maintaining Pavement Marking Retroreflectivity,” Feederal Register, 87(150), p. 47921, 2022.
10. “Standard Practice for Evaluating Degree of Traffic Paint Line Wear,” ASTM D913, ASTM International, 2020.
11. “Standard Test Method for No-Pick-Up Time of Traffic Paint,” ASTM D711, ASTM International, 2020.
12. “Standard Practice for Conducting Road Service Tests on Fluid Traffic Marking Materials,” ASTM D713, ASTM International, 2023.
13. For example, see: “Standard Specification for White and Yellow Reflective Thermoplastic Striping Material (Solid Form),” Specification M 249-12 (2020), American Association of State and Highway Transportation Officials, 2020.
14. For example, see: Texas Department of Transportation Specification DMS-8200, Traffic Paint, 2017.
15. For example, see: Federal Specification TT-P-1952F, “Paint, Traffic and Airfield Marking, Waterborne,” 2015.
16. The AASHTO Product Evaluation and Audit Solutions DataMine website for Pavement Marking. Materials can be accessed at https://data.ntpep.org/PMM/Products.
17. “Standard Specification for Glass Beads used in Pavemet Markings,” Specification M 247-13 (2018), American Association of State and Highway Transportation Officials, 2018.

��Leo J. Procopio, Ph.D., is president and owner of Paintology Coatings Research LLC.�� For more information, visit www.scienceofpaint.com or e-mail at leo.procopio@scienceofpaint.com.

By Leo Procopio, Paintology Coatings Research LLC

CoatingsTech asked several industry experts for their thoughts on the traffic paint and road markings market. Topics included the current state of the market and the commercial and technical challenges facing the industry. They also remark on exciting technical developments and new products, the role of sustainability, and provide their thoughts on the potential future for the segment.

Participants in the Q&A roundtable discussion include experts in the traffic paint and road-marking industry from raw material suppliers and coatings manufacturers. The industry experts providing comments include:

• Adam Fasula—marketing manager at Kraton
• Art Leman—NA marketing manager for road markings at Dow Coating Materials
• Kevin Lowe—director of product management for thermoplastics, PPG’s Traffic Solutions business
• Dan Stark—research specialist at Arkema Coating Resins
• Maria Wang—director of product management for liquid coatings, PPG’s Traffic Solutions business
• Angela Young—market segment manager at BASF

Expert Q&A

��Q: How would you describe the current state of the traffic paint and road marking industry, and what are some key challenges facing the industry today?��

Fasula (Kraton): The road marking sector continues to thrive at the present time, expanding steadily in many parts of the world, and is looking promising for the future. I have observed a remarkable unity within the road marking industry across the entire value chain, driven by our collective mission of enhancing road safety and ultimately saving lives. However, region-specific challenges impact the road marking industry, with labor availability being a significant concern in the United States. Despite sufficient funding for road marking projects, the industry faces limitations due to a shortage of skilled contractors, potentially hindering growth opportunities. Regulatory ambiguity, notably surrounding the Build America Buy America (BABA) Act, is another major issue for the US road marking business. Currently, there are gaps in the regulations, leading states to interpret the rules differently as they strive to comply. Comprehensive guidelines are eagerly awaited by the industry, as they are expected to bring clarity and consistency, enabling smoother operations and informed decision-making.

Leman (Dow):�� The state of the traffic paint and road marking industry is very strong with support from the Infrastructure Investment and Jobs Act bill passed in 2021. Also supporting our industry is an increased focus on road safety and reducing accidents and fatalities. Some key challenges in the recent past have been material supply and labor availability. While the material supply situation seems to have eased, there continue to be challenges with having enough labor to work on all the construction and maintenance infrastructure projects.

Stark (Arkema):�� Traffic coatings are critical to the livability and safety of urban areas – and represent strong opportunities for those companies investing in the industry. The future of the industry will be driven by a variety of factors, including continued pricing pressures, regulatory actions, the emergence of autonomous vehicles and innovation in other cementitious coating applications.

Trends include cool-pavement coatings, more colors beyond yellow to accommodate bike and pedestrian traffic, and the need for more sustainable coatings. Additionally, we anticipate growth driven by the Inflation Reduction Act and the need for longer-lasting coatings.

As autonomous vehicles begin to gain traction, the sector must adapt to ensure safety in a mixed-driver environment. This change will necessitate greater uniformity in traffic markings across various types and jurisdictions—local, state, and federal. Revisions to the Manual on Uniform Traffic Control Devices (MUTCD) in 2022 included retroreflectivity minimums and spotlight life cycle assessments and cost-per-road-mile comparisons for different marking types, stressing their growing significance.

Wang (PPG): The road marking industry is poised for growth on the tailwinds of the Infrastructure Investment and Jobs Act funding, and we are excited to provide a suite of solutions in our product portfolio to meet the needs of this growing market. PPG’s Traffic Solutions business partners with our customers to help them overcome challenges such as labor shortages and regulatory issues through new products and services that can help our customers improve their productivity.

Young (BASF): One key challenge the industry faces is the difficulty in funding roadway improvement projects. While we’ve made short-term gains, our long-term investment gap continues to grow. We need to get the funds allocated to the right jobs, get the right crews, and fund projects at the right time. I believe the US Infrastructure Investment and Jobs Act (IIJA) is a step in the right direction, but we still have a long way to go in addressing our infrastructure needs. Another challenge is created by the approval process for traffic paint markings. To get a product adopted, extensive work must be done with the DOTs. For that to happen, we must ensure our products do not impact any safety concerns and we must navigate the complexity of each state DOT. While there are challenges, there remain opportunities within this space.

Q: What are some key trends and drivers of technical innovation in the traffic paint market?��

Stark (Arkema): The emerging autonomous vehicles trend is steering the need for “smarter” road markings. These enhanced markings feature increased brightness, durability, improved adhesion, and heightened retroreflectivity, enabling better visibility on the roadways.

Wang (PPG): The US DOT zero deaths vision drives the FHWA guidance on wider and brighter lines, along with other local safety initiatives such as the Safe Streets and Roads for All program. PPG’s Traffic Solutions business has a pipeline of technical innovations to enable more durable lane markings with sustained retroreflectivity, enhancing driver visibility even in adverse conditions such as rainy nights. ��Additionally, the focus on performance in recent state specifications, as opposed to composition in older specifications, drives technical innovation and reduces the complexity of product SKUs for our customers.

Young (BASF): The number one trend in traffic paint is enhancing driver safety. There is a push for paints to be more retroreflective, for products to perform in harsher weather conditions and for extending the striping season so paint can be applied in cold weather applications. There are also new technologies that support, and continue to evolve, intelligent street marking systems that can communicate with the vehicle and other sensors.

Fasula (Kraton): Two key trends driving technical innovation in road markings are the aging population and the increasing adoption of autonomous vehicles (AV) technology. Aging populations require brighter markings with improved contrast in daylight and higher reflectivity at night. Additionally, machine vision relies on sharp-edged and more prominent markings for consistent recognition. The need for brighter, sharper markings with improved contrast and reflectivity poses challenges for scientists and formulators in developing superior reflective materials, enhancing glass bead adhesion, and improving the durability and visibility of road markings.

Leman (Dow): Selection of polymer continues to be a driver of increased durability in traffic paints. For example, most pavement marking products are known by their polymer descriptions, e.g., acrylic, epoxy, thermoplastic, etc. At Dow we continue to innovate new products and have launched FASTRACK™ 5408A to the industry for increased durability and retroreflectivity as well as colder temperature applications.

Q: What new technical developments do you consider exciting for the road maintenance and traffic paint segment?

Young (BASF): With autonomous vehicles imminent, road authorities must support both the human driver of today and the machine driver of tomorrow. That requires improvement of lane markings across the country and the ability for vehicles to interact with them. Two ways to accomplish this goal are to increase line width from 4 to 6 inches and use high-quality paint in road markings.

Fasula (Kraton): One of the most exciting advancements in the road marking industry is the development of technologies for wet-night visibility. Enhanced road markings that provide visibility in rainy conditions, such as structured markings that protrude through the water film and markings that employ specialized optics for underwater reflection, have the potential to save many lives.

Leman (Dow): Recently there have been updates to the MUTCD (Manual for Uniform Traffic Control Devices) which now establishes minimum retroreflectivity standards for pavement markings. While the requirements are not considered by many to be too stringent, it is a good start for ensuring pavement markings have good visibility, retroreflectivity, and maintenance. Autonomous vehicle features in automobiles such as lane keep assist rely on detection of pavement markings to work most effectively.

Stark (Arkema): Trends such as cool pavement, multiple colors, autonomous vehicles, and sustainable product development are driving the need for new solutions in these markets. Arkema is working closely with customers, suppliers, and organizations across the industry to identify the unique challenges these trends create and help produce the best possible solutions.

Wang (PPG): The trends towards automation, whether in application equipment or connected and autonomous vehicles (CAVs), open a new world of possibilities for pavement markings. PPG’s Traffic Solutions business is excited to work with our Mobility team within Automotive OEM Coatings on innovations that improve the safety and navigation of CAVs. We are also pursuing partnerships with equipment manufacturers to co-develop new coatings and automated application/monitoring processes to help improve safety in work zones. Currently several state DOTs are testing the use of ENNIS-FLINT® by PPG orange traffic paint and hot-applied thermoplastic to increase driver awareness of work zones for their safety and that of the construction workers.

Q: Do you have any new products or technologies for road markings that you would like to highlight, and what benefits do they bring?

Leman (Dow): FASTRACK™ 5408A is a new generation of all-acrylic emulsion for fast-dry waterborne traffic marking paints with improved durability. Traffic marking paints based on FASTRACK™ 5408A Emulsion feature fast dry over a broad range of application conditions and excellent durability in terms of retention of glass beads for night visibility and wear properties over asphalt, concrete, and previously applied markings. Other benefits of FASTRACK™ 5408A include enhanced retention of glass beads for excellent long-term night visibility, environmentally friendly formulated VOCs from 50 to 100 g/L, user friendliness, and extending the striping window to include paint application temperatures down to 35°F (and rising).

DURATRACK™ R-100 and AEH-100 Resins for Green Bike Lanes: Dow’s DURATRACK™ two-component (2K) technology for broad area markings make a great point for bicyclist safety. The green bike lane coatings increase the visibility of bicyclists for drivers, safety through clearly delineated space, and motorist yielding behavior to those in the lanes, as well as discourages parking in the bike lane. ��In addition, it yields pleasant results such as superior adhesion, skid-resistance, UV durability, and quick drying time, while enhancing work-zone safety through a speedy and efficient installation process. This traffic paint technology is projected to cut costs per mile by about 80%, which will hopefully lead to more green bike lanes.

Lowe (PPG): We are actively converting existing and new customers from granular hot-applied thermoplastic to THERMODROP® pelletized thermoplastic. This innovative pelletized thermoplastic material is a premium, pre-melted, homogenous, and fully encapsulated pavement marking compound that is provided in a free-flowing pelletized form. The results are 1) increased cleanliness, color efficiency, and material consistency; 2) increased productivity from longer runs and/or more runs per day, i.e., more “guns-on time”; and 3) reduced lane interruptions.

We are gaining market momentum with our HPS®-8 Integrated Multi-Polymer solution, which is a unique binder system composed of a series of polymers designed for high abrasion and impact resistance similar to traditional high-durability systems such as MMA and epoxy. However, due to the nature of these polymers, HPS®-8 Integrated Multi-Polymer is 100% solids and can be applied by standard thermoplastic extrude equipment at thicknesses as low as 50 mils and up to 120 mils. The polymers in HPS®-8 Integrated Multi-Polymer also offer excellent adhesion. Long-term retroreflectivity is achieved through an intermix of both Type 1 and Type 3 beads. Upon cooling to normal pavement temperature, HPS®-8 Integrated Multi-Polymer provides a very durable marking material for low and high-volume traffic areas.

Stark (Arkema): In 2023, Arkema will introduce ENCOR® 5650 acrylic, a new product for concrete coatings designed to offer improved blush resistance, longer life span, and improved hot tire pickup in applications such as garage flooring.

We also offer several existing binders that provide value to formulators of traffic markings:

• ENCOR® DT 250 latex, a high-performance second-generation fast-dry latex binder designed for optimum performance.
• ENCOR® DT 100 all acrylic, a general-purpose APEO-free binder with excellent durability and sustainability attributes.
• ENCOR® DT 211 all acrylic, a fast-drying binder for traffic markings applied at standard line thickness of typically 15 mils wet.

Wang (PPG): We are launching our next-generation Extended Season MMAX® area markings this summer. This proprietary methyl methacrylate (MMA) technology offers the widest temperature application range in the market. For the first time ever, it is possible to apply MMA markings such as green bike lanes and red bus lanes on pavement surfaces as hot as 150° F, which can happen even at air temperatures of 97°F. Extended Season MMAX® area markings are available in easy-to-mix kits with catalyst and corundum – the hardest, most wear-resistant anti-skid aggregate – making MMAX® area markings eligible for top-tier skid-resistance specifications.

Young (BASF): One exciting innovation that we are in the process of launching is our ACRONAL® Xpress 4360. This product is a development of a higher performance latex for waterborne traffic paint. The primary benefit is improved drying time. We are currently going through industry standard testing including NTPEP testing to validate long-term performance in real-world use.

Fasula (Kraton): Kraton has introduced several new products for road marking applications, with SYLVABIND™ C200 and SYLVABIND™ H300 being the highlights. These offerings mark the first entries from Kraton’s Polymer Modified Resin (PMR) technology platform. Leveraging PMR technology, formulators can design thermoplastic road markings with significant benefits. SYLVABIND™ products are resin-based, incorporating pre-blended elastomers to ensure ease of use and predictability during application. They also exhibit excellent glass bead retention, contributing to long-lasting visibility. Our C200 product is specifically formulated for cold to temperate climates, delivering exceptional impact resistance to withstand the abuse of snow plowing. Our H300 product is designed for temperate to hot climates, offering improved high-temperature compression resistance, which allows structured markings to maintain their profile, ensuring durable wet-night visibility. Kraton’s commitment to innovation and delivering solutions that meet the needs of global road marking professionals is exemplified by the successful outcomes of SYLVABIND™ C200 and SYLVABIND™ H300. These materials have demonstrated excellent results in road trials conducted by our customers in the Americas, Europe, and Asia, and they are now readily available for implementation.

Q: How is the industry and/or your company dealing with the topic of sustainability in traffic paints and road markings?

Wang (PPG): PPG’s Traffic Solutions business has a sustainability strategy for new product development and lifecycle management that supports our corporate ESG targets. Besides ongoing efforts to proactively reduce chemicals of concern in our formulations, as well as increase recycled content, we also offer sustainable packaging to our customers. Traffic paints are available in reusable asset totes that we pick up, clean, and redeploy in our production facilities.

Lowe (PPG): Additionally, the majority of our thermoplastic markings use alkyd resins which are sourced from suppliers utilizing sustainable forestry management practices.

Young (BASF): Sustainability will always remain an extremely important pillar for BASF. As federal specifications and environmental regulations tighten, waterborne traffic paint will continue to be a preferred road marking. The industry is currently balancing sustainability with cost and safety, but our team will continue to support stripers with individual state requirements.

Fasula (Kraton): Acknowledging Kraton’s longstanding leadership in sustainability well before it became a popular trend is important. Since the 1910s, Kraton has been a leading supplier of pine-chemistry-based materials. Our pine-based resins have been used to replace petroleum-based resins in US and European thermoplastic road markings because of the performance advantages they bring, especially glass bead adhesion and resistance to automotive chemicals. With our sustainability expertise and innovative materials, we have successfully assisted customers in achieving their sustainability goals by minimizing their environmental footprint, reducing microplastic contamination from road markings, and maximizing durability.

Leman (Dow): One of the benefits of longer lasting waterborne traffic paints is that they can extend the amount of time needed for replacement so that maintenance applications do not need to be conducted as often. This is also beneficial when there are challenges with labor availability and participation. Also, waterborne traffic paints do not require equipment to heat the material at high temperatures, saving energy and fuel.

Stark (Arkema): As a company deeply committed to the acrylic value chain, Arkema delivers a comprehensive range of materials for waterborne acrylic traffic paints. Our offerings span from monomers for acrylic emulsion production, to acrylic emulsions, rheology modifiers, and dispersing agents for these formulations. Sustainability and safety are at the heart of everything we do. We endeavor to eliminate harmful substances like VOCs and formaldehyde from our products, while also introducing renewable content into our formulations. A key aspect of our strategy is enhancing the durability of our products, a step which contributes to lowering the overall carbon footprint of traffic paints. This holistic approach allows us to provide effective, environmentally responsible solutions to the industry.

Q: What do you consider the most difficult technical problem facing raw material suppliers and coatings manufacturers of traffic and road marking coatings?

Fasula (Kraton): Some of the most challenging and intriguing technical problems are some of the long-standing challenges, such as ensuring visibility in wet-night conditions, delivering durability in diverse climates, achieving predictable adhesion to difficult-wearing courses, and addressing glare from low-angle sun for machine vision in the context of AVs. These problems necessitate ongoing research, innovation, and collaboration to develop solutions that balance visibility, durability, adhesion, and compatibility with evolving road surfaces and environmental conditions, ultimately advancing the industry and enhancing road safety.

Stark (Arkema): As autonomous vehicles begin to share the road with human drivers in more environments, there will be a growing emphasis on safety and durable, highly-visible traffic markings will be more important than ever.

Wang (PPG): Traffic paint is expected to dry within a few minutes on the road and yet needs to remain stable in liquid form before being applied. It is a very challenging technical problem to drive film formation during application but not in storage.

Lowe (PPG): This is compounded by the complexity from an overall product portfolio perspective, for paint and other markings, as the required color performance and other specs are different for each state.

Young (BASF): A technical problem facing our team is the ability to produce a fast-drying paint while maintaining stability. It is important to have a fast-drying paint that gets crews off the road quicker, and for the road to return to normal so that cars can come back. At the same time, we need the paint to not thicken or gel prematurely. There is always a pressure to meet the demands of the industry and we continue to evolve and develop products that meet those performance requirements.

Q: If you could predict the future, what changes and/or new innovations do you foresee for the traffic paint and road marking segment in the next 10 years and beyond?

Stark (Arkema): In the coming decades, the traffic marking industry will need to focus more on a lower carbon footprint, increased durability, and safer constituents. Likewise, ongoing engagement between road marking manufacturers and autonomous vehicle makers will be crucial. This collaboration will ensure alignment between the evolving requirements of autonomous technology and the markings that guide these vehicles, fortifying safety and efficiency on our roads.

Wang (PPG): My prediction is that we will see increasing functionality of pavement markings in terms of enhanced performance and mobility-enabling technologies while improving upon ease-of-application, robustness, and sustainability attributes of the products.

Lowe (PPG): Consequently, I think we will see a shift towards implementing solutions that are more cost-effective over the expected service life of roads.

Young (BASF): 10 years and beyond is a long time considering all the innovations that have come in the last 10 years. Obviously, safety will remain the top concern for this industry. We need to continue developing paints that dry quicker to get crews off the road and remain visible for longer to heighten driver safety. In the future, having road markings interact with autonomous vehicles will become increasingly important as well as applying paint in different weather conditions whether that be early rain resistance or another need.

Fasula (Kraton): Autonomous Vehicles (AV) manufacturers and suppliers made a wise decision in designing systems that work with existing infrastructure, acknowledging the reliability and elegance of pavement markings as a guide for machine control. Human vision will continue to be essential for years to come, and while connected vehicle (CV) technology is intriguing, pavement markings remain unmatched.

With the collaboration between the Society of Automotive Engineers (SAE) and road authorities, we can anticipate the trend of wider and brighter markings to continue. The increasing adoption of wet-night visibility solutions is also expected as road authorities prioritize safety enhancements. Looking ahead, we will witness the development of new solutions to address challenges like snow visibility and other complex scenarios for AVs.

Leman (Dow): Improved durability, performance, and low temperature application continues to be a market need. However, some of the changes can come from expansion of existing best practices such as taking regular retroreflectivity measurements of markings to determine their durability and performance on various road surfaces and traffic conditions. On our own test deck and from NTPEP data we continue to see wide variation in performance of waterborne traffic paints which can be improved by the selection of more durable polymers such as FASTRACK™ 5408A.

Lane markings are the positioning rails for automated driving systems and the guard rails for advanced driver assistance systems (ADAS). Road markings are critical to enabling AV Ready Roads, and this requires continued innovation and importance on the items above (durability, retro-reflectivity, etc.) ��The industry will continue to understand the differences between human vision and machine vision, in order to optimize markings for machine vision.

Leo J. Procopio, Ph.D., is president and owner of Paintology Coatings Research LLC.�� For more information, visit www.scienceofpaint.com or e-mail at leo.procopio@scienceofpaint.com.

Paints and coatings are typically used to beautify and protect, but there are many examples of specialty coatings that serve other functions.^1,2 The development of these “functional” coatings has been a trend in the industry for many years, and there are numerous examples such as soft-feel coatings for consumer electronics^3,4, sound-damping coatings for mitigating noise in automobiles^5,6, and antimicrobial coatings designed to kill microorganisms that come into contact with the coated surface⁷. Another trend in the paint and coatings industry has been the development of coatings that control the use of energy.

Access to energy is an important global driver for economic growth, and how we generate, efficiently use, and ultimately conserve energy has important consequences for the future of our environment and society. Coatings technology has an important role to play in this ongoing struggle.⁸ For example, coatings that can be cured at lower temperatures inherently use energy more efficiently.

The replacement of heavier bitumen pads with lightweight liquid-applied sound-damping coatings allows auto manufacturers to remove weight from automobiles.^5,6 Reducing weight of transportation vehicles uses energy more efficiently and improves mileage. Antifouling coatings help the fuel efficiency of ships by preventing the buildup of biofouling on the hull, which increases drag and makes engines work harder to achieve the same result.^9,10

Several types of functional coatings are targeted at managing thermal energy. Cool-roof coatings keep the interior of buildings cooler and lighten the load on air conditioning during the hot, sunny days of summer. High solar reflectivity and thermal emissivity helps the coating deflect energy in sunlight, preventing the roof from heating up as much, and thus less heat is conducted through the roof and into the building.^11,12 Cool coatings for exterior building walls also function in a similar manner.

Cool coatings also help defend against the urban heat island effect, where urban environments with large areas of dark roofs and paved surfaces tend to be warmer than nearby rural areas. Thermal insulation coatings are also used to manage thermal energy for both personnel protection and energy conservation purposes.¹³ However, thermal insulation coatings rely on a different mechanism and prevent heat transfer between materials due to their low thermal conductivity.

In this article, we introduce thermal insulation coatings and the science behind how they work. First, a discussion on the physics of heat transfer and thermal conduction will provide some necessary context to understand how insulation works. A description of traditional insulation materials and some lingering problems with those materials will give perspective into why thermal insulation coatings were developed, followed by a description of how thermal insulation coatings are formulated, applied and perform. A brief comparison with cool-roof coatings will also be given to clarify common misunderstandings about functional coatings and how they each help with energy management.

MECHANISMS OF HEAT TRANSFER

The flow of heat between materials is controlled by three basic mechanisms: conduction, convection, and radiation. Consider the simple scenario of heating water in a pot shown in��Figure 1, which is often used to explain the three mechanisms. When heat flows through a solid material, it is by conduction. An example of conduction is the flow of heat from the fire, through the metal of the pot, to the hand holding the pot handle. The rate of conductive heat transfer depends on the chemical nature and structure of the solid material. If the pot in��Figure 1��is a cast iron skillet, the cast iron handle could get very hot, and an oven mitt might be needed to touch the handle with your hand. Many pots have handles made with or covered by a different material such as wood or plastic. The conduction of heat through those materials is slower than through metal, so pots with those handles can often be held with a bare hand.

Convection is the transfer of heat by the movement of a fluid; either a gas or liquid. In��Figure 1, heated water moves from the bottom of the pot, which is closer to the heat source, upward toward the cooler surface. In this case, convection involves the movement of a liquid. In a similar manner, convection involving the movement of a gas is a process that causes warm, lighter air to rise and cold, denser air to sink within a house, resulting in upper floors often being warmer than the lower floors. Another example of convection involving a gas is shown in��Figure 1, where the boiling water evaporates as steam, which rises from the hot water surface and heats up the cooler air above. In these examples, convection occurs because of differences in the density and buoyancy of hot and cold regions of the liquid or gas. Hotter, less dense fluids will tend to rise, and colder, denser fluids will descend.

Heat can also be emitted from a material through radiation in the form of electromagnetic waves, such as infrared (IR) radiation. Heat transfer through radiation results in the warmth we feel when we hold our hands near a fire, as shown in��Figure 1, or when sunlight heats a dark roof or an asphalt parking lot. Anyone walking in bare feet on hot asphalt pavement during a sunny summer day experiences the result of heat transfer by radiation. Radiation is also the mechanism through which the hot roof or asphalt pavement releases (or emits) heat into the surrounding air and cools down once the sun sets.

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To achieve that goal, the company had to overcome two key challenges presented by applying coatings in the field. Factory coatings are customized to the surface being painted, and they are applied under highly controlled conditions that are optimal for painting. Therefore, customization of coatings to the surface being painted and adjustment of the coating formulation to match the environment would be needed to create a similar applied appearance in the field.

How can that be accomplished? Only with a deep understanding of coatings chemistry and the ability to apply advanced software technology to solving the problem. “Our motto is to use chemistry to create smart renovation solutions that make our customers happy by making their lives easier,” says Marsala. After thousands of hours in the lab, the company developed a solution that enables the adjustment of a paint formulation based on the expected weather conditions, the nature of the surface to be painted and the customer’s color selection. “Some surfaces need flexibility and breathability, while others need heat resistance and hardness. We customize each coating to perform based on a substrate’s unique properties for the best results,” Marsala explains.

Their solution is patented, thus making Spray-Net the only exterior painting company that can provide a real-time, weather-adjusted paint job, according to Marsala. The result, he adds, is a long-lasting finish that won’t peel, does not require maintenance every 2 to 5 years and looks like-new, not repainted. Spray-Net delivers a factory finish on aluminum and vinyl siding, stucco, brick, fiber cement, roofs, and even surfaces that are not traditionally painted on-site, like front and garage doors, windows, and kitchen cabinets.

When homeowners Spray-Net their homes, they get more than a regular paint job, Marsala stresses. “Leveraging chemistry and technology makes us a different kind of painter, and it’s what allows us to innovate new renovation solutions that provide homeowners with value,” he asserts. “Building owners get a real and cost-effective alternative to replacement with Spray-Net, because our coating solutions instantly transform the look of a home for a fraction of the cost of brand-new siding, doors, and windows,” Marsala observes. “We offer a whole new way to renovate.” Spray-Net’s goal is to provide every homeowner with a renovation that increases property value, is practical, cost-effective, and makes them fall in love with their home all over again, he concludes.

Spray-Net, because it is selling home transformations and not paint itself, invest in the latest coating technologies and top-of-the-line ingredients to equip its painters with the premium paint they need to deliver factory-quality results on siding, doors and windows, according to Marsala. Its paint line includes acrylic dispersions for aluminum, fiber cement and engineered wood siding, two-component polyurethanes where protection from UV rays, abrasions and regular washing are required, breathable elastomeric copolymer emulsions for stucco and a silicate stain that forms a chemical and mechanical bond with brick. Proprietary software enables customization to real-time weather conditions at the time of application (temperature, humidity and wind levels) to ensure optimal film formation, end properties and lasting results.

Coating formulation at Spray-Net’s in-house paint lab takes approximately 2 weeks, including building the customer’s color selection into the paint by balancing the resin-to-pigment ratio for each color, making sure there is sufficient pigment for optimal coverage, making sure there are enough resins to encapsulate pigments for maximum fade protection, according to Marsala. In addition, the company also uses high-grade, inorganic, solar-reflective pigments. The coatings are also optimized for exterior spray application and atomized at an optimal viscosity and custom thickness to achieve streak-free, sag-free, high-build finishes in one coat, according to Marsala. When the work on site begins, typically the building is power-washed and window and door surfaces prepped on day one, with painting completed on day two. For smaller homes, however, projects can be completed in as little one day. Paints are dry to the touch within 15 to 30 minutes and then finish curing with exposure to ambient temperature. When needed in unideal weather conditions, the company can produce a forced bake for front doors in its mobile spray booth given that this high-traffic surface requires a quick, full cure.

Marsala is not done innovating yet, either. “We might have succeeded in bringing a factory finish on-site, but there’s so much more we can’t wait to do,” Marsala insists. “Imagine if we could customize the coating on your front door according to how much direct sun exposure it gets? The possibilities are endless (and exciting)!”

Spray-Net has locations across Canada, and several new franchises in the United States, including in Columbus, OH; Chattanooga, TN; and St. Louis, MO. ��The goal is to expand nation-wide in the United States, and the franchise is actively seeking new partners.

By Cynthia Challener, CoatingsTech Contributing Writer

Core paint and coatings manufacturing processes have remained largely unchanged since the dawn of the industry. Ingredients are mixed into a liquid (organic solvent or water), a process that is often followed by milling to achieve the correct particle size for products comprising dispersions. Despite this, the paint and coatings industry is very dynamic. Business trends, market demands, governmental regulations, scientific innovations, and other forces are continually prompting changes that call on manufacturing equipment suppliers to provide new solutions.

One such change, the move from normal steel to a primarily stainless steel construction for high-speed dissolvers (HSD), occurred over the last 70–80 years, according to Hans-Joachim Jacob, senior process engineer and customer application specialist at ystral gmbh maschinenbau + processtechnik. “HSDs are low-shear machines, but high-shear forces are often required for proper dispersion of paint ingredients. These forces can be generated by increasing the viscosity, but the viscosity changes from the start to the end of a process, requiring careful control by the operator. As a result, processes today are still heavily influenced by the specific operator, and a cyclical mix—quality check—adjust with additives and repeat system is used that can be time consuming,” he observes. Jacob believes it is time for a change. “Instead of relying so heavily on additives to solve performance issues,” he says, “the industry should be doing more with technology, such as to prevent foaming.”

Other changes, such as to formulations and batch sizes, have made it a challenge to produce new products in legacy assets, according����to Stuart Rae, advanced manufacturing director at AkzoNobel. “There is need for greater agility to handle smaller batch sizes with the same levels of efficiency and cost, even for formulations that have lower levels of biocides, so they require higher levels of hygienic conditions. The reduction in biocide use for consumer water-based products has, in particular, created challenges to ensuring product quality given existing raw material quality, storage, and legacy plant designs. Smaller production orders, meanwhile, require the same cleaning times and incur higher residual losses, and thus process and product redesign are needed to enable sustainable manufacturing under current conditions,” he explains.

In addition to cost-effective performance, equipment reliability is fundamental, adds Stewart Rissley, chemical market manager with Admix.

Echoing that sentiment, Sara Fulford, VP of sales and marketing for Hockmeyer Equipment Corporation, says, “Achieving the delicate balance between productivity and consistently manufacturing a high-performance product is the top priority.”

With so many options and elements to consider—and with limited time and resources—it can be difficult to identify equipment that maximizes efficiency and performance. “Customers have to find a way to sensibly assess how equipment will perform for their unique products. It has to fit into their current process seamlessly and ideally eliminate steps to enable leaner processes without requiring reformulation. Factors such as cost, space requirements, manpower, cleanability, ergonomics, safety, and reliability also have to be considered,” Fulford advises.

Indeed, time is money, and the less time it takes to process a product, the better, adds Schold sales engineer��Amy Karony. Improvements in milling efficiency can significantly affect processing time, for instance. Whereas long residence times may be necessary in many horizontal mills, Karony says Schold has found that processing time can be reduced by up to 50% or more in certain applications by replacing horizontal milling operations with immersion or basket mills.

Due to tight budgets in the current business climate, many paint manufacturers use a single piece of equipment in the production of coatings products with very different properties. In these cases, versatility is essential. Karony points to thin and extremely viscous products as an example that requires different gearing and/or additional blades to ensure proper mixing. Versatility of equipment is also needed with respect to batch volumes, she notes, pointing to the wide range of batch sizes many smaller-volume coatings manufacturers make on any given day or week. “Post-mounted/tank-mounted batch-style machines can be used only for certain volume sizes that aren’t sufficient to meet the volume ranges many customers have today,” Karony says.

Jacob adds that paint processing equipment should also be flexible enough to enable everything from color changes to switches in resins and other ingredients that might be incompatible. “The ability to produce different batch sizes and different product types using a single system allows coating manufacturers to invest more in one system, because it can replace multiple pieces of older equipment,” he says.

Greater knowledge of mixing within the paint industry is also needed, according to Jacob. “The type of tank and agitator system should be chosen based on the specific application. A process tank, for instance, requires higher performance and a higher power-per-volume ratio than a simple storage tank,” he explains. Solventborne and waterborne formulations also have different requirements; with its higher surface tension and polarity, mixing powders into water requires much higher power/energy concentration, Jacob notes. Powder handling in all paint production processes presents another challenge for the industry with regard to protection of operators from breathing in fine dust particles and eliminating explosion hazards associated with the addition of powders from the top of the tank. Scale up from lab to the plant can be another challenge, particularly in Europe; in the United States and many other countries, intermediary pilot scale runs are performed using scale-down production equipment with the same shear speeds, flow rates, and energy/power densities as large-scale plant equipment to ensure processes are optimized for in-plant conditions.

Remote Operation and Digitalization

One of the most important technology developments enabling greater efficiency and productivity combined with consistent quality and enhanced operator safety is digitalization of process equipment for remote, automated operation. “In the past, liquid mixing
has been somewhat of an art, but as more and more companies move to reduce human operators in the interest of both cost and safety concerns, the [greater the] need for consistency and quality improvements, and as lab-developed formulations have become more and more unique, even in smaller operations, companies are moving toward automated or semi-automated equipment to aid with quality control,” Karony explains.

Indeed, the ability to run lights-out once a batch has been started increases productivity and can reduce costs significantly, Barry Cullens, director of R&D and process applications for Hockmeyer Equipment Corporation, adds.

Some equipment manufacturers report growing interest in the ability to operate production equipment remotely. “In this age of connectivity,” says Christine Banaszek, sales manager for Charles Ross & Son Company, “a growing number of our customers are interested in adding a Remote Access Device (RAD) for their Ross Mixers. With this technology, operators and supervisors with an internet connection can monitor and control machines remotely. In some cases, that even includes the use of a central base located in another building, city, or even country, allowing the same recipes to be produced in the same manner regardless of location,” according to Jacob.

Others, however, anticipate a future that continues to draw on operator skill with assistance from new technologies such as remote operation. Cullens believes, for example, that given the current level of incoming raw material batch-to-batch inconsistencies, there will always be some level of operator activity, even under the most technologically advanced, remotely controlled environment. “It is unlikely that we will see complete hands-free operation; there will always be some art mixed in with the science,” Fulford says.

A complementary trend is continuous data acquisition, a process that is generally facilitated by the use of automated systems. Jacob reports that systems exist today that contain all of the recipes produced on a production line with the capability to automatically schedule runs in an order that optimizes switches from one batch to another, minimizing cleaning requirements. There are even some self-teaching systems that can continuously learn about dosing conditions after each run and apply that learning to improve operations for the next run.

Digitalization is a tool for quality control. “Manufacturers are opting for customizable recipe-control systems capable of logging all process variables to a CSV [comma-separated value] file of batch history records,” Banaszek says.

Digitalization is also a tool for increasing equipment longevity. “Customers like to have a maintenance screen incorporated into the mixer control panel that can display automated reminders for preventive maintenance duties such as checking belts, greasing bearings, etc.,” Banaszek explains.

Mixing Technology

Greater efficiency is also being achieved with the introduction of newer mixing technologies. For coating manufacturers that prefer to continue using HSDs to combine dry and wet raw materials, reliability, robust design, and ample horsepower are still the main considerations, according to Banaszek. For other companies, innovative designs offer an opportunity to further extend processing flexibility and decrease downtime. As one example, she points to a swivel design disperser that is raised out of the tank at the end of the mixing cycle and rotated 90 degrees to service another vessel while the first tank is drained and set up for the next run. Admix, meanwhile, has developed high-shear technology that performs reliably with lower power consumption compared to legacy equipment, affording greater energy efficiency, according to Rissley. He notes batch times are greatly reduced and that rapid production of 100% powder dispersions is possible, because the company’s patented high-shear head design provides the optimal balance between shear and flow. “With high flow, there are no dead zones in the tank, and, therefore, the product passes through multiple shear zones/surfaces in a short amount of time, resulting in agglomerate-free mixtures in under 10 minutes,” Rissley asserts. The technology is suitable for both large and small batches and, therefore, ideal for customers serving smaller and/or more diverse markets.

Inline mixing is another important advance in efficiency. Schold offers inline disperser models that provide the opportunity to combine mixing wet and dry product with the use of a rotor stator to also achieve significant particle size reduction in one pass for many raw materials, according to Karony. She adds that the equipment is also offered as a portable skid system, providing the agility needed to meet manufacturer expectations for flexible production solutions. The portable skid includes the Schold inline disperser, a small tank, and various equipment additions such as a powder introduction inlet and/or tank agitator. “Originally developed in response to the recent high demand for industrial detergents and sanitizers, interest in this type of equipment is extremely high in the current atmosphere and also finding wide use by customers in various industries, including the paint and coatings sector, that need versatile and portable solutions to many different processes in their plants,” states Karony.

Vacuum Systems

Rapid-flow vacuum milling and dispersion technology, meanwhile, is designed to enhance efficiency for customers trying to make more batches, faster, with less waste and easier changeovers, according to Fulford. Hockmeyer has developed a line of equipment for dispersing, milling, and homogenizing under vacuum that removes air trapped in the feedstocks to facilitate faster, purer particle size reduction and deagglomeration. It can thus reduce process times significantly, increasing productivity and yields, she says. In some cases, Cullens notes that the technology allows formulators to incorporate less or maybe even no defoamers, which can be advantageous from both performance and cost perspectives.

The dispersion under vacuum expansion from ystral provides more than enhanced efficiency, according to Jacob. Because powder is drawn into a recirculating loop via a vacuum, it has already been wetted before entering the tank, avoiding the risk of explosion and reducing operator exposure. He notes that the expanded distance between the individual particles under vacuum also means that single particles are dispersed, and agglomeration is largely avoided, eliminating the need for milling in nearly 80% of cases. A residence time of less than a second under shear force allows for the use of shear-sensitive ingredients, according to Jacob. Separate from the actual mixer, the system also works with many different tanks sizes and can be cleaned in place for rapid changeover without risk of cross-contamination of different pigment colors or other ingredients. It can additionally enable substantial reduction of the amount of wetting agent needed. This is because the powder is not being added to the top of the tank and may result in less hydrophilic surfaces that, in architectural applications, could lead to a reduced need for biocides.

For high-value and high-performance coatings, a closed mixing system is preferred by end users, according to Banaszek. For example, she says the Charles Ross & Son Company custom-builds multi-shaft mixers and planetary dispersers for coatings applications in the electronics, aerospace, medical, and other markets. These machines “are especially capable of high-viscosity mixing under vacuum and at precise temperatures,” she says. For such specialized solutions, Banaszek says it is best to begin product development in partnership with a reliable equipment manufacturer and select a scalable R&D mixer to eliminate common issues that often occur when scaling up to full-scale production.

Schold, meanwhile, has developed a vacuum solution for mixing within drums and smaller vessels in response to customer requests. “We have a great many customers mixing and producing their products right in 55-gal drums for downstream process convenience. Our solution makes it extremely simple to secure the drum under the mixer, lower the vacuum bell, pull full vacuum, and process the batch. It removes the complexity of vacuum mixing and the need for specific vacuum-rated mix vessels,” she explains.

Simplified Manufacturing

Two other developments from equipment manufacturers are supporting trends within the coating industry to simplify manufacturing. In one case, because manufacturing continues to move to ever larger production batches, producers have been interested in adopting powder-feed systems rather than handling hundreds of 50-lb bags per batch, according to Cullens. Instead, powders are being delivered to paint manufacturing plants in intermediate bulk containers or even rail cars/tankers for incorporation into production processes using automated feeding systems. Fulford expects the use of such auto-feed powder systems will continue to grow as an equipment category in the coatings space.

The other concept seeing greater acceptance, particularly in Asia, is the production of intermediate slurries, such as of titanium dioxide, which are optimally dispersed and then stored on site for a period of time. Slurries with multiple ingredients can also be made. This approach is particularly efficient if the same slurries can be used for the production of multiple products and an automated system is used for the final product mixing.

Paint manufacturers of all sizes are leveraging all of these new technologies to some degree. “We are working with suppliers and product formulators to apply agility in design and in the way products are manufactured through a range of different options; this

includes manufacturing from intermediates, filling lines designed for rapid changeovers, late differentiation of items, and modifications to improve yield on smaller production runs,” Rae states. AkzoNobel has also implemented in recent years various processes and technology to improve the recovery and reuse of by-products to reduce waste, increase material efficiency, and deliver savings. Currently, Rae notes the company is interested in solutions that will further enable late differentiation of products through efficiency in filling operations and the decoration of packaging.

Working with Novel Materials

Though novel and complex materials used in coating formulations may present challenges, those challenges are positive ones that can be translated into opportunities, reasons Rissley. Admix technology, for instance, can be configured into low-/high-shear devices for batch and continuous process modes, he notes.

Processing equipment must also be able to convert lower-quality materials into high-quality end products, observes Karony,�� given that companies are switching to lower-quality materials to reduce raw material costs. “Machines such as inline dispersers and immersion mills that are designed to inherently provide for waste minimization and increased raw material utilization are important solutions for this issue,” she says.

Nanomaterials have also become important in coating formulations, and many require special processing conditions. Pigments that are purposely processed to the nanosize, for instance, often have coatings applied to them to prevent re-agglomeration. “It is important to separate these particles without removing the coatings, and, therefore, new milling techniques address this need for what appear to be paradoxical processes,” Fulford says.

Other pigments are not nanoscale but have special shapes (i.e., sheet form or ball form flakes) that must be preserved for them to perform properly. “For these formulations, mill speed, media size, and media density all play a role and have to be carefully balanced, and often vacuum milling rather than atmospheric milling is the only way to achieve the desired results,” Cullens observes.

For many new resin and additive technologies, temperature control has become an important process parameter. “Over the past 30 years, we have seen a steady decrease in maximum batch temperature due to new resins, pigments, nano dispersions, applications, etc.,” Cullens comments. With inline mixing, the processing temperature can be controlled to fit the formulation by adding inline jacketed tubes either before or after the processing equipment. “The cooling efficiency of inline heat exchangers is much greater than just having a cooling jacket on the supply tank. In fact, with the rapid flow rates used to disperse or mill materials, the maximum batch temperature will dictate the mill or disperser speed to maintain the feedstock under the maximum temperature. Running the mill slower will reduce the impact between the media and the rotating parts, thus limiting the equipment capabilities and can greatly increase processing times or prevent the desired particle size from being attainable,” he explains. With inline cooling, on the other hand, it is possible to operate a mill or disperser at full speed, maximizing the throughput without high-temperature issues, Cullens concludes.

New equipment available today also makes it possible to manufacture materials that cannot be produced using high-speed dissolvers, according to Jacob. With the dispersion under vacuum expansion technology, for example, the ability to control the amount of heat generated enables the production of sol-gel systems, including plastisols and organosols, that cure at temperatures near 100 °F and can only be produced at temperatures below 90 °F. Vacuum systems also make it possible to incorporate extremely light fillers (nanosized bubbles filled with gas), which cannot be added by pouring out of a bag, for light-weighting as well as for use in cool-roof coatings for diffraction and reflection of infrared light. Inline dispersion also increases the effectiveness of novel dispersing additives comprising backbones with long side chains. These additives are often destroyed when added to dissolver tanks at the beginning of the mixing process; controlled addition at the right time is possible with the use of inline mixing technology, according to Jacob. Similarly, working at different pH levels in the tank and in the inline mixer makes it possible to control the addition of pH-activated materials to coating products.

Supporting Small Coating Manufacturers

Smaller shops generally want smaller, high-quality equipment that is also reliable and affordable, according to Rissley.

Versatility is also essential. “Small shops that focus on the development of formulas using emerging technologies need equipment that is readily adaptable, with the ability to serve multiple functions, process a wide variety of materials, and capture data for thorough detailed analysis,” states Fulford.�� “These environments call for machines that are designed to achieve fast and reliable results and accurate scale up with safe, ergonomic designs, due to substantial hands-on operator involvement,” she adds.

In addition to being versatile, they must also be robust and provide agility via quick changeovers and shorter production runs, because these capabilities are what afford small shops their economic advantage over larger companies, according to Karony. For instance, she notes that for low-viscosity products, the cleanup time can be reduced substantially by purchasing CIP equipment. “If the solvent used in cleaning is compatible with the end-product, the cleaning solution can be blended into the letdown to eliminate raw material waste, further improving safety, environmental, and housekeeping practices by not having a person manually clean the machine,” she adds.

With HSDs, the bottleneck is usually quality control and adjustment, with the total batch time reaching five hours or greater, but operator involvement at perhaps two hours, according to Jacob. With inline mixing technology such as the system ystral offers, the bottleneck becomes powder handling, and the run time is optimized when unloading of the powder into the hopper is optimized. This situation is an additional driver for the use of automated powder feeders.

It is also driving interest in the production and use of intermediate slurries for the most difficult to handle and important raw materials, even at smaller coatings producers, Jacob observes.

Providing equipment that can be used at different scales and for different functions is also important. Most companies are now offering scale-down versions of plant equipment for use in the R&D and pilot settings. Schold, for instance, has developed a lab mixer that can be used in the R&D lab and for quality control testing that is capable of blending, mixing, dispersing powders, homogenizing, emulsifying, and even milling lab-size batches on the same frame, according to Karony. It can also provide vacuum or heated/cooled processing and can be built with three different motor sizes, allowing use for a wider range of batch sizes. “The operator can change attachments to fulfill various lab needs and thus eliminate the need for four different machines, which in turn reduces the amount of capital investment needed for a lab,” Karony says.

Hockmeyer has also developed lab and pilot-sized units that can be adapted to agitate, mix, disperse, homogenize, mill and nano-mill materials up to 500,000 centipoise (cps), according to Fulford. Notably, the systems can work under atmospheric or vacuum conditions, and the temperature of the feedstock can be easily regulated. Furthermore, customization to include rapid recirculation under vacuum technology is also possible, comments Fulford.

The key to providing optimum solutions for smaller shops, Rissley asserts, is listening to the “Voice of the Customer” and providing customized solutions for the given application. “To help customers avoid the trap of selecting low-cost equipment that underperforms and results in lower yields or the use of outdated and inefficient technologies that can’t keep up with production demands, Admix partners with customers to understand their applications, ingredients used, end-product quality goals and current capacities versus demands. We are then, using our long ingredient and applications experience, able to customize high-performing, built-to-last solutions that greatly improve their current processes and result in increased yields and the highest quality end-products possible,” he says.

Schold is also a custom equipment manufacturer and works with shops to alter equipment as needed to meet their specific plant footprint and processing needs and to support the transition to more automated processes, according to Karony. “Currently no one machine can continuously and properly incorporate all ingredients AND reduce particle size. Schold can help assess the application and facility situation from greenfield projects to line expansions and by using our expertise in the industry and our equipment knowhow and system design experience to develop unique solutions that help our clients reduce bottlenecks and create balanced processes,” she states.

CoatingsTech | Vol. 17, No. 9 | September 2020

Energy consumption impacts not only costs, but sustainability. Reducing energy consumption, therefore, reduces costs and lowers greenhouse gas emissions. The coatings industry is helping to reduce energy consumption in many ways. Manufacturers are developing more efficient processes for the production of coating ingredients and formulated paints. Resin manufacturers are developing new technologies that cure at lower temperatures, and equipment manufacturers are boosting the performance of curing equipment to expand the applicability of more energy-efficient alternative curing mechanisms. Coatings that contain novel resin and pigment chemistries are increasing the energy efficiency of buildings, cars, and airplanes.

Manufacturing Efficiency

In the manufacture of key ingredients of basic raw materials—resins, additives, pigments, fillers and solvents—and formulated paints and coatings, there are numerous opportunities to improve energy efficiency and achieve energy savings, according to Robertino Chinellato, global R&D director for Powder Coating Resins with allnex. “The specific actions that can be taken depend, of course, on the different manufacturing processes involved, but approaches for heat recovery, achieving greater energy efficiency, and general process optimization to improve yields and reduce cycle times can be considered for all industrial processes used in the paint and coatings industry,” he says. Options include the use of alternative energy production technologies such as tri-generation technology, which provides three forms of output energy using natural gas as the fuel: electrical power, heat, and cooling.

As examples, James Martin, global operational excellence manager at allnex, points to the use of variable frequency drives on motors powering fans and centrifugal pumps to match the power demand, avoiding the use of excess energy, and reducing the use of distillation processes by implementing more efficient solvent recovery systems. Advanced process modeling has also helped the company reduce energy consumption in highly integrated distillation columns. In addition, Martin comments that operational analytics have helped allnex to better understand and monitor energy systems and energy flows, enabling the company to identify opportunities to reduce energy consumption more quickly.

Covestro is highly committed to the United Nations Sustainable Development Goals, according to Steven Reinstadtler, infrastructure marketing manager at Covestro LLC. “By 2025, 80% of Covestro’s R&D project spending will be targeted in areas that contribute to achieving these goals, which include realizing energy savings,in our own production of coating raw materials as well as in processes related to their use on the customer side,” he says. Reinstadtler adds that Covestro’s efforts to develop more energy-efficient solutions are often pursued in close collaboration with partners.

Most coating companies also have sustainability initiatives that include reduction of energy consumption. AkzoNobel, for instance, recently announced its intention to move the company towards zero waste and to cut its carbon emission in half by 2030. “This initiative is part of the ‘Planet’ element of our new ‘People. Planet. Paint.’ approach to sustainability,” notes Rinske van Heiningen, AkzoNobel’s director of Sustainability. Targets for 2030 include a 30% reduction in energy use, 100% electricity derived from renewable sources, 100% water reuse at the company’s most water consumption-intensive sites, and zero non-reusable waste. Electricity from renewable sources is already in use at 33 locations across eight countries, including the installation of solar panels at 14 sites. “To help us achieve our energy reduction goals, we see the greatest opportunities for decreasing energy consumption with utilities, such as compressors, chillers, cooling systems, and LEV and HVAC solutions,” van Heiningen says. The company has already seen significant reduction of energy consumption thanks to modern, energy-efficient equipment in utilities, but also in motors, pumps, and drives. Achieving “right first time” improvement has had a huge impact on energy savings, according to van Heiningen.

PPG is committed to reducing energy consumption to minimize greenhouse gases (GHGs), reduce costs, and create more efficient facilities, according to PPG executive vice president, Tim Knavish. “While the vast majority of our coatings are manufactured at ambient temperatures and pressures and, therefore, are not energy-intensive, we are focusing on making the milling step more energy-efficient,” he observes. One way to increase energy efficiency in coating manufacturing, agrees Mark Ryan, marketing manager for The Shepherd Color Co., is by using easily dispersed pigments, which reduce the need for time and energy-
intensive pigment dispersion steps.��He notes that Shepherd Color’s Dynamix pigments eliminate the small-media milling step while also reducing the re-work needed for off-spec batches.

PPG is also shortening cycle times and making other relevant changes to reduce the energy required to manufacture its coating technologies. The company’s Natural Resources and Climate Change Subcommittee of its Sustainability Committee oversees PPG’s energy-reduction strategy, determining the greatest opportunities to decrease energy use. Key energy efficiency initiatives include creating a culture of energy conservation through communication and awareness-building; developing a PPG standard for energy management based on ISO^® 50001 and ENERGY STAR^®; identifying and focusing resources on locations with the highest energy use; sharing best practices across the organization; exploring partnerships with energy solution firms; and increasing the company’s use of renewable energy. Specific goals set in 2018 include a 15% reduction of energy consumption intensity by 2025 from a 2017 baseline and increasing renewable energy to 25% of total electricity usage, exclusive of GHG reductions by 2025.

“Our global locations have been successful in decreasing their individual energy usage by following the ENERGY STAR guidelines and through the commitment of our people to reduce energy in the workplace, from small steps such as turning off the lights to installing energy-efficient equipment,” Knavish asserts. He describes, as one example, the installation of more than 180 solar panels on three buildings at the PPG Aerospace Applications Support Center (ASC) in Tullamarine, Australia. The solar panels provide 70,000 kWh of power, reducing the center’s annual electricity consumption by 27% and related costs by 38%, as well as GHG intensity.

Cool Cure

A second significant area with potential to dramatically reduce energy consumption—this time during coating application—is the development of resin technologies that cure at lower temperatures. “The trend to reduce temperatures during curing of paints has been an important driver over the last couple of years,” notes Chinellato. A variety of opportunities exist, including lower-temperature powder coatings; switching to ultraviolet (UV) curing systems; faster-curing, two-component (2K) polyurethane systems; and new technology systems with inherently faster chemistry, according to Robert Skarvan, global marketing director for Liquid Resins and Additives with allnex.

From the perspective of powder coatings, there has been a drive to increase the reactivity of binder chemistries so that coatings can be cured either at lower temperatures or over shorter periods of time, notes Robert Watson, global marketing and business development manager for Powder Coating Resins at allnex. “The current state of art is that some powder coatings can be cured at temperatures of 130–160°C, depending on technology type. Having lower-curing coatings means massive metal componentry, which is slow to heat, can reach curing temperature faster, and thus increase throughput, saving energy,” he explains. He adds that while powder coatings are typically associated with metal finishing, new developments in lower-temperature curing are now starting to open up wood substrates such as medium-density fiberboard (MDF), commonly used in furniture, to powder. Another goal for powder coating is to target a wider range of thermally sensitive substrates, including plastics and composites. Allnex is currently developing a novel binder for powder coatings based on new chemistry that enable reduced curing temperatures, Chinellato adds.

Interpon Low-E powder coatings from AkzoNobel, meanwhile, are specially engineered for curing at temperatures lower than the current standard of 180–190°C for triglycidyl isocyanurate (TGIC)-free polyesters. “These products can help our customers reduce their energy bill by up to 20% or increase their output by up to 25%,” says van Heiningen. The coatings are designed for use in a wide range of applications, including industrial steel products, street and garden furniture, and agricultural and construction equipment. The coatings are also suitable for use in interior or exterior environments.

In the future, Watson also expects lower-temperature curing of powder coatings to be increasingly important for electric vehicles (EVs). “As EVs become more prevalent, there is a greater tendency to light-weighting to increase range. Traditional metals could be replaced with thinner metals or non-metallic substrates.��As the nature of these substrates change, the curing characteristics of coatings will also have to change, and this trend will drive greater use of lower-temperature curing systems and, therefore, lower energy,” he explains.

In the liquid coating space, allnex offers ACURE^® technology, a new non-isocyanate chemistry with inherently faster cure speed vs conventional 2K urethane systems. “The main driver for the development of this system was, in fact, faster cure. It is the non-isocyanate nature of the chemistry that provides that faster cure,” Skarvan observes. “Whether ACURE or other faster-curing 2K systems are used, curing oven temperatures may be reduced,” he adds. The company has also developed a line of faster-curing acrylic and polyester polyols. One current need is for faster-curing primer systems that can be paired with fast-curing topcoats. Wet-on-wet systems that eliminate a baking step are currently common in automotive and industrial OEM applications, according to Skarvan, and their expanded use will also lead to further decreases in energy consumption.

PPG, in order to decrease energy consumption for automotive OEM customers, has introduced a low-cure paint technology to the automotive market in 2018. “Before our low-cure paint technology, approximately 70% of total energy consumption at an automotive assembly facility took place in the paint shop. Our low-cure technology uses up to 39% less energy through a next-generation clearcoat that cures at about 175°F (80°C) compared to nearly 285°F (140°C) for current systems. Added benefits include a simplified manufacturing process and smaller paint shop footprint,” Knavish observes. From a UV coatings application perspective, primarily in packaging coatings and inks, but also for industrial wood and construction and industrial plastics, Michela Fusco, global marketing director for Radcure at allnex indicates that the greatest energy efficiency opportunities are connected to the adoption of UV light-emitting diode (LED) ��lamp technologies as replacements for traditional mercury lamps. “LED lamps used for UV curing of coatings enable higher energy efficiency in cycling operations due to the ability to switch the systems on and off instantly. “Recent advances in UV LED lamps and their use in combination with UV LED curing systems is enabling broader applicability of UV LED technology in the coatings industry,” she observes. She notes that these developments have been driven by limitations with respect to surface cure when using earlier versions of LED curing lamps, which has prevented wider adoption of this coating technology. “Further improvements are still needed in this area to make the most of the energy efficiency potential of LED curing technology across different coatings applications,” Fusco adds. The use of LED lamps and the challenges with surface cure are, in fact, driving the development of LED-fit resins and boosters. For instance, allnex recently launched EBECRYL LED 03 oligomer, which has enhanced reactivity when used as a co-resin in UV-curable formulations, according to Fusco. She also notes that allnex is optimizing LED boosters for ink technologies and improving the LED cured surface performance in wood applications.

Pigment technology can impact the energy efficiency of some coating applications. Shepherd Color’s patented Niobium Tin Pyrochlore (NTP) Yellow pigment in the middle-yellow color space has excellent durability, chromaticity, and opacity that organic pigments cannot match, according to Ryan. This innovative pigment expands the envelope of durable color and serves as a bridge between the high chromaticity of organic pigments and the durability and opacity of inorganic pigments. “The increased opacity allows for single-coat color matches, eliminating the need for multiple coats of passes through the paint application process, thus saving time, energy, and materials,” he remarks.

Textile manufacturers are also achieving greater energy savings and reducing GHG emissions due to a new coating technology developed by Covestro. When a transfer coating process using INSQIN^®�� water-based technology is used instead of the conventional solvent-based coagulation process, the relative GHG potential of synthetic-coated textiles produced is 45% lower, according to Bob Saunders, head of Textile Coatings North America at Covestro LLC. “If the entire textile industry were to switch to water-based technology from Covestro, for example, the resulting greenhouse gas reduction would be comparable to the elimination of all cars driving on the streets of London, Hong Kong, and Los Angeles,” he comments.

Coatings that Contribute

Coatings, once applied to substrates, are also helping to reduce energy consumption in several ways. Coatings such as those from PPG provide environmental and sustainability benefits to end users. “Our innovations contribute to a healthier, greener environment without sacrificing appearance and color flexibility. They reduce corrosion and extend the customer product lifetimes. They help reduce energy usage and emissions, protect customer employees, and minimize waste and water consumption,” Knavish says.

One example of an energy-saving technology from PPG is PPG POWERCRON^® 160 anionic epoxy e-coat, a significant technical advance in electrocoat technology that enables high film builds (greater than 6 mils) over multiple substrates and pretreatment chemistries. Previously, according to Knavish, anionic e-coats had to be matched to specific pretreatments and metal substrates, which added complexity, cost, and energy use to the coatings process.” PPG Powercron 160 coating cures at lower temperatures than conventional anionic e-coats, which further reduces energy use and related carbon emissions,” he notes. The technology was developed to meet the unique corrosion protection requirements of the pipe industry and is engineered for manufacturers who finish complex cast profiles in the castings, automotive, heavy-duty equipment, and other industries.

While not necessarily energy-saving, PPG has also developed novel technology for aircraft windows to significantly block harmful UV radiation and high-energy visible (HEV) light to help protect aircrews, passengers, and aircraft interiors from solar radiation. PPG windows with PPG SOLARON BLUE PROTECTION™ UV+ blocking technology block 99% of UVA and UVB radiation and more than 50% of HEV (blue) light. The new technology is incorporated into PPG’s windows at the time of manufacture and can be applied to cockpit and cabin windows.

Driving Efficiency

In the automotive sector, light-weighting has not been restricted to EVs. In all passenger and commercial automobiles, light-weighting has become a well-known way to increase fuel efficiency and save energy. Dow’s ACCOUSTICRYL™ Copolymer Emulsions are one type of coating technology designed to help with light-weighting. These coatings, according to Ramesh Iyer, sustainability director for Dow Coatings and Performance Monomers, are increasingly used in automobiles to reduce structure-borne noise for a quieter interior by replacing incumbent heavier bitumen pads, reducing weight by up to 35%. “In 2018, about 96 million vehicles (passengers and commercial vehicles) were produced. This translates to an opportunity to reduce over half a million tons of CO₂ emissions, enough to take approximately 108,000 cars off our roads for a year,” he comments.

In addition to sound-dampening coatings, the light-weighting trend is also leading to greater demand for specialty elastomerics that offer benefits such as vibration reduction, according to Sanjay Luthra, business development and marketing manager at Arkema. “Advances in raw materials that offer lower coat weights and high-performance attributes are critical to ongoing success in the industry,” he asserts. Additionally, with the growing prevalence of plastics in vehicle construction, he notes that there is greater need for adhesion to low-energy substrates. “Many of our customers are using elastomeric coatings formulated using specialty waterborne acrylic and styrene acrylic copolymers, as well as hybrid, silane terminated urethane and polyether polymers to address this need,” Luthra says. He adds that incorporating foam into the coating systems allows for additional light-weighting that ultimately leads to lower energy consumption.

Coatings In Supporting Roles

Coatings also provide protection to wind energy towers and solar panels, indirectly aiding in energy efficiency, according to Luthra. “Furthermore, for these applications, the myriad coating technologies that allow for reduced numbers of paint layers or layer thicknesses all contribute to reduced overall object weight and, thereby, reduced energy consumption,” he states.

Light-weighting is also important in the building and construction sector, where use of higher-performance acrylic copolymers with increased hydrophobicity and tensile strength is allowing the reduction of coating weights for functional applications, Luthra says. Such applications include impregnation of glass fibers for dry-wall facers��and higher-performance coated, prefabricated concrete panels for use in tilt-up walls and modern building fabrication methods. “These coatings allow for thinner and lighter-weight fabrications that result in reduced energy consumption during transportation without compromising the durability,” he explains.

Newer air and vapor barrier coatings that constitute a component of advanced building envelope systems also allow buildings to conserve energy during their use. These coatings have to be regionally engineered, however, to meet local codes and building specifications, according to Luthra. They��contain a balance of hydrophobicity and permeability to allow air, water vapor, and moisture flow as well as contribute to the insulation and fire resistance properties of the walls. “Organizations such as the Air Barrier Association of America are instrumental in creating and managing the specifications for such coating systems,” he observes.

Cool roof coatings are perhaps one of the best-known ways in which coatings help conserve energy. Elastomeric cool roof coatings have been important for decades. “These coatings provide benefit by reflecting sunlight and lowering air-conditioning costs of buildings and warehouses, as well as imparting waterproofing protection that allows prevention of costly maintenance costs due to water damage,” Luthra explains. Recent innovation focuses on regional and specific needs driving reductions in energy consumption, such as newer systems that, rather than being white, have slight color imparted to them to address specific application and community color requirements, according to Luthra. He adds that a modified ASTM D-6083 Specification (ASTM D-6083 type 2) for elastomeric roof coatings is allowing coating manufacturers to address roof coating needs more for the sunbelt states. “These coatings do not need the low-temperature flexibility required in the snow belt states, but do need excellent early water, dirt pick-up, and UV resistance, as well as adhesion to multiple substrates,” he says.

Another emerging coating technology for high-end roof coatings is aqueous water-based fluoropolymer roof coatings. While these coatings have a higher unit cost, they offer significantly higher performance with respect to durability, Luthra comments. They are applied to a wide variety of substrates as thinner films compared to elastomeric acrylic roof coatings but provide the traditional unparalleled color and UV stability for which fluoropolymers are well renowned.

Another trend in the fluid-applied roof coating market is a switch from aromatic polyurethane coatings, which have helped to address market needs for a longer-lasting, durable and seamless waterproofing membrane on low-slope commercial roofs, to one-component (1K) and 2K aliphatic polyurethane roof coating systems with long-term UV and weather resistance. The driver, Reinstadtler says, is the increased awareness of the energy-saving benefits of reflective roof assemblies. Aliphatic polyurethane roof coatings provide the hail resistance, wind uplift, rain resistance, and seamless long-term flexibility of aromatic systems while also ensuring that surfaces retain their original color (often white) and, thus, their high-infrared (IR) reflectance for a longer period. “The UV resistance of the employed resins and aliphatic hardeners keeps the membrane from yellowing or darkening over time, which can impact the solar reflectance. Additionally, the excellent resistance to weathering keeps the coating surface smooth and non-porous longer, reducing dirt pick-up and mildew growth that can impact solar reflectance and ultimately, the energy savings of the reflective roof, explains Reinstadtler.

Advances in IR-reflective pigment technology, meanwhile, are enabling the formulation of colored cool roof coatings for residential and other sloped-roof applications. For instance, Ryan notes that Shepherd Color’s Arctic IR reflective pigments are used around the world in building and construction applications to extend product lifetime and reduce the amount of solar energy absorbed.��In addition to reducing cooling loads for specific buildings with cool roofs, the reduction of sunlight absorption can also reduce the urban heat island effect. “Shepherd Color is on our 5^th generation of products that maximize a jet masstone, high tint-strength, and high Total Solar Reflectance (TSR).��We like to say that we have a range of products to fit your specific need—a veritable ‘Black Rainbow’ of products,” he observes. The company’s IR-reflective pigments are combined with its Dynamix easily dispersed technology for further energy savings during production.

Reflectance can also be important in interior spaces. “Often overlooked in the built environment is the effect of gloss and color on the overall lighting requirements,” remarks Reinstadtler. He observes that in industrial, warehouse, and retail spaces, the requirements are typically in the 200- to 100-foot candle range. But in critical task areas or showrooms, the requirements can rise to over 250-foot candles. “In these areas, floor coatings can contribute to significant energy reductions by reflecting natural and artificial light in a space due to their inherent gloss level and pigmentation,” he says. “In particular, a light-stable aliphatic polyurethane or polyaspartic is preferred due to their ability to retain a high gloss over time, ensuring continued light reflection. Additionally, a lighter pigmented floor designed to reflect ambient light will benefit from the long-term color stability imparted by the use of aliphatic hardeners in polyurethane and polyaspartic floor coatings,” Reinstadtler adds. For instance, in a large warehouse example, the owner was able to reduce the artificial lighting requirements and, therefore, the energy consumption in the space by roughly 20% by specifying a gloss white aliphatic polyurethane topcoat.

Also, in the building and construction segment, polyaspartic coating technology is helping to reduce energy consumption. When used as a concrete floor coating, there are clear, tangible energy savings, according to Reinstadtler. In northern climates, floor-coating can be challenging in early spring and late fall due to permeation of colder outdoor temperatures into buildings. The current solution, says Reinstadtler, is to turn up the heat on the existing HVAC system or to deploy electric or propane torpedo heaters to raise the temperature of the air and concrete, thereby expending energy. “By using polyaspartic floor-coating technology, contractors are able to complete more jobs in the shoulder season without the need to raise the ambient and concrete temperatures, which reduces energy consumption,” he notes. The faster working time of polyaspartics can create challenges, though, particularly for less-experienced contractors who are not familiar with polyaspartics. “As a workaround, they may use a longer working time polyaspartic coating on a cold-weather job and turn the ambient heat up even more to get a faster cure rate,” Reinstadtler says. One area of innovation, therefore, is designing new polyaspartic resins that offer both a longer working time and a quicker return-to-service time, even in colder weather.

There are opportunities for reducing energy consumption in many other industries as well. Dow has developed CANVERA™ Polyolefin Dispersion for metal cans, which provides significant sustainability advantages over traditional epoxy-acrylic coatings, according to Iyer. “Every 1000 cans coated with CANVERA Polyolefin Dispersion lowers the global warming potential of each can by 20% on a relative basis versus conventional BPA-based epoxy-acrylics,” he says. The company’s ROPAQUE™ Opaque Polymers and EVOQUE™ Pre-Composite Polymers, meanwhile, reduce the need for titanium dioxide (TiO₂) extenders in architectural coatings. While TiO₂ is good at imparting hiding and brightening, it requires large amounts of water and energy to mine and purify to make it suitable for use in paints, Iyer explains. The combination of Dow’s two technologies can partially replace TiO₂ in paints and utilize the remaining TiO₂ more efficiently. “Our lifecycle analysis of ROPAQUE Opaque Polymer and reported industry information about TiO₂ indicate that the carbon footprint��for a typical ROPAQUE Opaque Polymer is nearly half that reported for TiO₂ on a ‘dry’ per-kg basis. Therefore, partially replacing and more efficiently using TiO₂ present a large opportunity to reduce the carbon footprint of selected paints in their lifecycle,” Iyer asserts.

Separately, Ryan notes that the ultimate efficiency for a coating is a long lifecycle.��“The repainting process is time-consuming, expensive, and uses more materials, leading to greater energy consumption. A coating needs to keep its performance properties along with its aesthetic appeal,” he says. The company’s Complex Inorganic Color Pigments (CICPs) are inert and durable with outstanding weathering properties, according to Ryan. While high-temperature calcination is required to produce them, he strongly believes the investment in energy needed to make the pigments is more than balanced by the reduction in overall energy usage achieved due to the long lifetimes of the paints and coatings formulated with those pigments.

Going forward, Luthra notes that the paint and coatings industry will be challenged to meet the demands of an increasingly circular economy. “Recyclability and incorporating greater use of renewable content in coating raw materials are ongoing challenges for everyone in the industry. However, with increased focus and commitment to this area, innovation is sure to follow and help drive the growth of the global coatings industry,” he concludes.

CoatingsTech | Vol. 17, No. 5 | May 2020

Aromas are known to often be connected to previous experiences and to elicit certain emotions. Using scented coatings, therefore, provides a mechanism for marketers to develop a personal connection between their brands and consumers. Including scents in packaging also creates interactive experiences for end users, driving greater interest and ultimately increased sales. According to H&H Graphics, studies have shown that scents are recalled more strongly than images, and companies like Yankee Candle and Mitsubishi have experienced measurable increases in sales following the use of scent in their advertising campaigns.

Most scented coatings, unlike scratch and sniff slurries, are formulated as aqueous air-dry or UV-cured systems that can be applied using a variety of processes, including sheetfed or heatset litho printing, flexo printing, gravure printing, and silkscreen printing. In addition, scented coatings can be applied directly to the packaging itself or to product labels, while scratch and sniff stickers must be printed separately and then affixed to the package.

Scented coatings can be used on magazine and catalog inserts, direct mail pieces, and a variety of packaging materials, as well as applied to tissue paper, greeting cards, construction paper, wrapping paper, and other products. Scented coatings can also be used for very practical purposes, such as safety/education. For instance, sulfur compounds used as additives in propane and natural gas can be encapsulated and applied in marketing materials to educate consumers so that they can recognize when a gas leak is occurring. In addition to H&H Graphics, they are offered by companies such as Scentisphere, Ronald T. Dodge Co., and ScentSational Technologies.

Scented coatings are formulated using microencapsulated fragrance compounds or essential oils. Generally the same fragrance ingredients that are used in a branded product are used to make the scented coating for a marketing campaign so that consumers experience the actual aroma of the product in the advertising material. In November 2012, ScentSational Technologies launched in collaboration with Sun Chemical SunScent™ coatings, commercially printable coatings that are applied directly onto packaging (film, cartons, paperboard, or other packaging materials) on commercial print presses as the package is being printed. They remain inactive until the package is handled by the consumer, which triggers release of the aroma chemicals. These coatings allow consumers to experience the aroma of the product simply by touching or handling the packaging and without opening it. The company also offers EncapScent™ Coatings that contain scented microcapsules that rupture when the product is handled.

Los Angeles is using coatings to tackle the problem, according to a story in The Washington Post ().

The material urban heat island effect occurs because heat is trapped in cities due to the presence of congested buildings, concrete and dark roofs and dark asphalt streets that absorb solar energy. It is worse in cities with little plant life—trees, bushes, etc.—to mitigate the effect. Los Angeles, not surprisingly, has experienced significantly rising temperatures due to the urban heat island effect because it is surrounded by desert and covered with acres of asphalt. By 2037, the city’s Mayor, Eric Cargetti, wants to reduce the average temperature of Los Angeles by three degrees, and he has cool coatings in his arsenal.

He hopes that by painting roadways, parking lots, airport runways, and other paved areas with CoolSeal, a grey coating specifically designed to reflect solar rays, the air temperature in these areas will be reduced, leading to fewer heat-related deaths and a reduced need for air conditioning. CoolSeal was initially developed by California-based, asphalt coating manufacturer GuardTop in conjunction with the defense industry, which was seeking a cool pavement solution for military spy planes, according to the company’s vice president of sales Jeff Luzar.

The city has tested the coating in a few ways.�� In 2015, a parking lot in the hottest part of the city was painted with CoolSeal. According to Greg Spotts, the assistant director of the Bureau of Street Services, the area covered with the coating was on average 10 degrees cooler than the black asphalt in the same parking lot. The city has also applied the coating to designated streets in 14 of the city’s 15 council districts and is monitoring the effects through fall 2017. Pets have also been found to walk on coated pavement that they avoid when it is uncoated.

According to Spotts, approximately 10% of Los Angeles is asphalt—about 69,000 city blocks. He believes that coating just one-third of that asphalt could have help to reduce the average city temperature. Currently, the city is evaluating the cost of applying the coating on a large scale. It costs approximately $40,000 per mile and lasts seven years.

“Porcelain- and glass-covered dry-erase surfaces cannot be formed, which limits their potential use in a wider array of office products,” says Dan Chin, president of Unichem, a custom adhesives and coating formulator. “Their weight also poses limits in the size, application, and mounting of dry-erase boards,” he adds.

The new dry-erase coating is formulated for coil-coating application onto aluminum and steel substrates, which can then be formed, bent, and/or cut to create dry-erase surfaces for use in homes, offices, appliances, and other products. Coil coating is a high-speed process in which a coating is applied to a variety of metal substrates such as aluminum, cold rolled steel, or hot dipped galvanized steel. The coated materials are then shipped for later fabrication and forming into parts or products. Unlike porcelain and glass, a coil-coated substrate with a special dry-erase coating can be precision slit, stamped, sheared, roll formed, and incorporated into a wide range of sizes or shapes, according to Chin.

“In addition to post-forming of the coated-coil substrates into whiteboards, which can be incorporated into wall panels, partitions, and office furniture installations, the flexibility of these coated materials allows for the formation of aesthetically curved or 3D surfaces that can be used by manufacturers, architects, and interior designers in entirely new applications,” Chin notes. Coil substrates weigh less than glass and porcelain, and thus the dry-erase “boards” produced with the new coil coating are much lighter, making installation simpler. Furniture containing them are also lighter and more easily moved and shipped.

As importantly, the Uni-rase coating has improved dry-erase properties, such as excellent ghosting resistance or shadowing typical of many current competitive products on the market. Unichem has tested their dry-erase coatings with more than 100 markers from different manufacturers, including permanent markers. “In the erasability tests, the coating has to show little to no ghosting as well as meet the durability (mark-erase cycles) testing,” says Chin. “It is also important to build in resistance to moisture because some common dry erase products tend to ghost severely in high humidity climates.” The coating survived over 10,000 cycles of erasability as well as heat and humidity cycling and passed stringent requirements for cleanability for all of the markers tested (the permanent markers were removed with spray cleaners).

Another unique characteristic of the Uni-rase coating is its ability to allow for sublimation printing of logos and branding, including photo quality images or other graphics. Dry-erase boards by their nature are designed to prevent ink from sticking, and as a result typically only the printing of simple graphics is possible. Uni-rase, however, is designed to accept photographic quality sublimation inks, making it possible to incorporate impactful, complex images that have the same dry-erase properties as the rest of the coated surface. “The coating is capable of high image clarity, and accurate ink transfer in the sublimation process results in photo-quality transferred images,” Chin says. As a result, dry-erase “board” manufacturers can customize white boards for specific use by including complex images for branding purposes—either their own or their customers’—without affecting the dry-erase performance of the product.

The sublimation process used to create the images essentially introduces heat to turn solid ink particles directly into a gas, which permanently colors the surface and sub-surface of the dry-erase board, preventing the ink from washing away, according to Chin. The use of�� the specially formulated dry-erase coating makes this process possible. Because the sublimation image is embedded into the coating, writing over the image with dry-erase markers is not a problem and will not have any negative effect on the quality of the sublimated image. “Now you can infuse (sublimate) permanent inks into the coating—such as for photos, logos, patterns, calendars, or industry-specific formats or graphics—yet retain dry-erase board erasability,” says Chin. “The image in the coating is every bit as good as the actual printed photo, so it enhances visual impact and aesthetics.”

The chemistry behind the Uni-rase coating is proprietary, but Chin does observe that it is the result of significant R&D time and effort devoted to development, testing, and verification. “This technology was a result of very intentional formulation of a system that would outperform competitive products,” he says.

Currently, the coating is available only as a coil coating, but it could be made available in a spray application if desired, according to Chin. The coating can also be adjusted for use in a number of different applications, such as post-painting. With respect to substrate preparation, he notes that the surface to be coated must be properly cleaned (free of oil and dirt) and dried before application.

Unichem works closely with the service centers that coordinate the metal and coating purchases, the coil coaters that apply its coatings, and the furniture OEMs that purchase coated substrates for incorporation into their products, according to Chin. “We have very good relationships with everyone in the supply chain; it takes a cooperative combined effort to service the OEMs,” he explains.

CoatingsTech | Vol. 15, No. 2 | February 2018

By Aggie Lotz, The ChemQuest Group, Inc.

In May 2017, the fifth edition of the Global Market Analysis for the Paint & Coatings Industry (2015–2020) was released by the International Paint and Printing Ink Council (IPPIC). Prepared by its international consultant, the ChemQuest Group, Inc., the report features extensive research findings and insights into global and regional coatings in 11 end-use segments as well as sub-segments. This article provides an overview of intumescent coatings, an important sub-segment of industrial maintenance coatings that is contained in the report.

Industrial Maintenance and Protective Coatings ������

Industrial maintenance and protective coatings are formulated to provide protection for exterior and interior substrates against corrosion, abrasion, thermal, and chemical and ultraviolet (UV) degradation in both industrial and critical service environments. These coating systems, as the name indicates, are used primarily in industrial segments where aggressive corrosive or chemical environments exist, in addition to commercial applications where long-term protection and aesthetics are required. While such coatings are primarily considered functional, appearance and retention of these coating systems have also become important performance requirements.

Industrial maintenance and protective coatings are combinations of products designed to perform and protect under specific conditions. Such coatings systems are usually applied by specially trained, professional applicators in a fabrication facility or in the field. They can be applied as part of new construction, or during routine maintenance to provide continued asset protection from various forms of structural deterioration.

Industrial Maintenance Coatings Types

Dominating the industrial maintenance coatings segment is solventborne coatings—including both conventional and high-solids products—accounting for approximately 65% of 2015 total volume. The majority of industrial maintenance solventborne coatings are high-solids products, as the industry strives to meet ever-tightening environmental regulations without sacrificing product performance. Included in the high-solids category is 100% solids technology that plays a key role in severe service applications. It is used extensively in tank linings, deck coatings, and secondary containment. They are mostly epoxy, novolac, and even aromatic polyurethane when impact resistance is required to improve wear. The trend toward high-solids coatings is expected to continue.

Emerging Technology and Trends

One example of an end market pushing the performance envelope for conventional coatings is the oil and gas industry. A current trend is toward higher pipeline operating temperatures to increase transportation volumes. Therefore, a common characteristic is the elevated temperature of the oil (up to 150°C and potentially even higher). This directly impacts pipeline coating performance that can degrade at elevated temperatures, resulting in internal and external corrosion problems affecting such flowline systems.

In the past 10 years, one solution to mitigate external pipeline corrosion has been the use of epoxy/phenolic resin-based coatings; these perform reliably up to 120°C. High-temperature, epoxy/novolac matrices can handle constant or repeated temperatures up to 177°C in dry conditions and 149°C in the wet, but they require a thermal cure—not practical for many field applications.

Nanotechnology refers to materials with dimensions in the 1–100 nanometer range, where quantum mechanics yield interesting properties. Nanostructured materials yield extraordinary differences in rates and control of chemical reactions, electrical conductivity, magnetic properties, thermal conductivity, strength, and fire-retardant properties.

Intumescent Coatings������

One type of functional coating is a fire-retardant variety (also known as an intumescent coating) to insulate steel substrates exposed to fire. The fire-retardancy property is project-dependent but generally understood to mean a coating can withstand temperatures in the range of 200°C to 600°C for a period of time.

The demand for intumescent coatings is closely tied to construction spending. The split between U.S. residential and nonresidential construction is 60/40. Nonresidential construction spending continues to increase (4.1% in 2016). Construction markets showing double-digit, year-over-year growth include lodging, office, and commercial structures. Public construction, in areas such as water supply, sewage treatment, and public safety, was down slightly in 2016, but the short-term outlook is positive, depending on U.S. infrastructure spending. Overall, the average growth in total construction spending has been a robust 8.1% over the last five years. Figure 1 contrasts public and private construction growth for the United States in value (2009–2016).

There is demand for intumescent coatings in specialty coatings sub-segments, such as marine, transportation, onshore/offshore oil and gas production, and new industrial and commercial construction. The increased use of lightweight materials for transportation, modular homes, and insulation applications is a key driver. Intumescent paints are increasingly used to protect spherical structures containing natural gas, peroxides, and other chemicals.

Of special importance in new construction of commercial buildings, intumescent coatings incorporate flame-retardant chemicals to achieve two distinct industry efficacy ratings. The first measures flame spread, or how effectively the coating limits flammability (according to ASTM E84). The second rating demonstrates coating efficacy for delaying and resisting the effects of fire (expressed in hours), as shown in Figure 2.

Industry definitions may aid in a better understanding of what an intumescent coating (also known as fireproofing) is and is not. According to SSPC’s 2011 Protective Coatings Glossary, a fire-retardant is a
“ . . . product, under accepted methods of test, that will significantly: (1) reduce the rate of flame spread on the surface of a material to which it has been applied, or (2) resist ignition when exposed to high temperatures, or (3) insulate a substrate to which it has been applied and prolong the time required to reach its ignition, melting, or structural-weakening temperature” [ASTM D 16]. Flammability is defined as the ability to catch fire (a flammable material burns quickly and easily). Inflammability can sometimes mean “not flammable.” SSPC has separate definitions for a flammable aerosol, gas, liquid, and solid material, based on their respective properties to ignite and burn, according to various test methods. Moreover, an intumescent coating, according to SSPC’s definition, is “a fire-retardant coating that when heated forms a foam produced by nonflammable gases, such as carbon dioxide and ammonia. This [reaction] results in a thick, highly insulating layer of carbon (about 50 times as thick as the original coating) that serves to protect the coated substrate from fire. See also FIRE-RETARDANT [ASTM D 16].”

By comparison, heat resistance is defined by SSPC as “the ability of a coating to resist deterioration when exposed continuously or periodically to high temperatures at or below a given level. Heat resistance depends on the binder type and other coating ingredients.”

In summary, a heat-resistant coating and an intumescent coating have different properties and chemistries; therefore, the terminology should not be used interchangeably. The difference between the two types of coatings is that an intumescent coating insulates the substrate from fire, i.e., protecting it against heat transfer. However, a heat-resistant coating will—by some measure—resist degradation from heat, yet it does not insulate or protect the substrate from heat. Consider, for illustrative purposes, the coating on grills: the coating itself will not degrade but the metal becomes very hot when in use.

Protective coatings with heat-resistant properties are used in light- and medium-duty industrial maintenance applications, such as production equipment refurbishing. Flame-retardant coatings are typically used for decks, walls, rails, and load-
bearing steel beams and support columns. High-heat and/or flame resistance is also important in heavy-duty maintenance coating applications for refineries and furnaces, jet engine components, and transportation engine parts—such as exhaust manifolds and gaskets. Their selection is not solely driven by a specific need for thermal protection, but also by new and existing fire codes/regulations promulgated following 9/11. ASTM D2485-91(2013), Standard Test Methods for Evaluating Coatings for High Temperature Service, is a test method that provides an accelerated means of determining acceptable performance of coating systems developed to cover steel that may be potentially exposed to high temperatures during its interior and exterior service life.

Other examples of ASTM test methods and UL codes for fire protection coatings in commercial and industrial construction are noted in Table 1.

In new construction applications in the oil and gas industry, a “massive change” moving toward OEM fireproofing was a trend noted in 2015; whereas fireproofing in maintenance and repair applications, by comparison, could be cost prohibitive. In older plants, installing intumescent coatings sometimes requires removing cementitious structures (otherwise “hidden” corrosion behind the concrete—left untreated—can put the cementitious structure at high risk of collapsing). Concrete removal is where the high cost emerges.

Typically, intumescent coatings technology includes vinyl toluene acrylics, styrene acrylics, silicone acrylics, fluoropolymer, epoxies, urethanes, and chlorinated rubber. For cellulosics, intumescent coatings can be either solvent- or waterborne, with the latter generally based on vinyl acetate or acrylic. In contrast, those used against hydrocarbon fires are all epoxies. Thin film is typically used in general construction including structural steel, while the thick-film coatings tend to find use in the oil and gas industry, such as for protecting petroleum refineries. Depending on the application, an array of low-VOC, (often) thick-film chemistries can be used to achieve specified requirements—such as the ability to adhere to urethane foam.

Major manufacturers of intumescent coatings and fireproofing products include Carboline, StanChem, Flame Control, Isolatek, Flame Master, Benjamin Moore, Sherwin-Williams, PPG, AkzoNobel, Jotun, and many others. Due to the critical properties that fireproofing imparts to steel structures, the proper application of intumescent coatings is essential to ensure public safety. SSPC’s Train the Painter (TTP) is addressing the need for industry training and qualification criteria through its two-part Coating Applicator Specialist training module for Intumescent Coatings: section 2.1 is for Thin-Film; section 2.2 is for Thick-Film.

Top-line growth opportunities for intumescent coatings may include properties such as low smoke generation, combustion prevention, and a polymer for formulating thinner films to improve aesthetics on steel surfaces. Eliminating the need for a topcoat over the intumescent product may also be desired in some exterior applications.

The International Paint and Printing Ink Council’s (IPPIC) expanded fifth edition of the Global Market Analysis for the Paint & Coatings Industry (2015-2020) provides comprehensive market research covering the global paint and coatings industry, addressing topics of relevance to coatings manufacturers, end users, raw materials suppliers, private equity firms, and others interested in the industry.

Prepared by The ChemQuest Group, Inc., IPPIC’s international consultant to the specialty chemicals and coatings industries, the report covers three primary categories of coatings: Decorative, Original Equipment Manufacturers, and Special Purpose, as well as the many sub-segments within those categories. Chapters focus on sector analysis, market trends and drivers, and competitive landscape.

The fifth edition of IPPIC’s Global Market Analysis was expanded to include new features such as additional forecast data, an expanded raw material chapter, as well as a new chapter on mergers and acquisitions. Additionally, the fifth edition is far more comprehensive in scope to include—as is the subject of this article—an overview of intumescent coatings as a growing sub-segment of industrial maintenance and protective coatings.

For more information on the content of IPPIC’s Global Market Analysis for the Paint & Coatings Industry (2015–2020) and to purchase the digital download, visit paint.org  (Publications & Resources online store) or contact Steve Sides at ssides@paint.org (202.462.6272 x225).

CoatingsTech | Vol. 15, No. 1�� | January 2018