In the coatings industry there is a growing demand for environmentally friendly materials that can replace those harmful to health due to tighter regulation but also as a result of greater awareness among consumers. Technologies such as waterborne coating resins, powder coatings and radiation curable coatings are shining examples of the paint and coatings industry's innovation towards this end.
Radiation curable coatings are "cured," or dried, using energy from ultraviolet (UV) or electron beam (EB) sources instead of conventional heat and do so more quickly, using less energy and thereby at lower cost than by other methods.
Like other segments of the coatings industry the "radcure" market was impacted by the recession. "General macro-economic conditions drained most markets of cash and other drivers and resources," said Lou Palermo, partner at The Chemark Consulting Group. "Most UV/EB coatings segments took a significant hit mirroring the decreases in the general coatings market, while some specialty applications continued an above average growth rate due to the infancy of their product life."
Now that the contraction phase appears to have ended, according to Palermo, there is a cautious enthusiasm as photocure technology resumes the day-to-day job of what trade organization for manufacturers of UV- and EB-cured coatings, RadTech, coined the "5Es of UV/EB"-efficiency, enabling, economical, energy-saving and environmentally-friendly.
Radcure By The Numbers
Representing 1.9% of all coatings globally, and predicted to increase to a 3.0% share by 2013, the total value of global radcure coatings in 2009 was $1.541 billion, up 5.1% from 2006, according to Chemark.
Demand in North America was strongest at 57,593 tons valued at $538.5 million. In the EU, demand was just behind at 55,753 tons valued at $518.5 million. Growth rates for the North American and EU markets for 2009 were 4.0% and 4.1%, respectively.
Rest of the world (ROW) markets for radcure coatings were valued at $484.0 million last year. Together the ROW markets are growing at a rate of 8.5% per year, while China alone is growing at a rate of 12.5%.
In 2010, Chemark estimates global radcure coatings will grow at 7.5% to $1.660 billion. Growing at a rate of 7.5% per year, the global radcure coatings market will reach $2.410 billion by 2014.
While growth prospects for the radcure coatings segment are positive, operating in a post-recession environment is complicated. Perhaps more than any other obstacle, the paint and coatings supply chain is caught in a tangled web of pricing issues.
Chemark's Palermo said after a period of stagnation, converters and end users now have a heightened resistance to price increases. "At the same time, basic raw material prices are increasing due to consolidation, plant closings and shortages," he said. "These trends result in reduced margins for the formulators thus forcing chemists to reformulate products to achieve performance with lower cost materials."
An example would be the transition from urethane acrylates to specialty polyester acrylates and in some cases epoxy acrylates, Palermo said. In addition, recent raw materials supply shortages have delayed growth due to line shutdowns.
Technology for the Future
Coatings manufacturers and raw material suppliers alike continue to innovate new technology for radcure coatings.
Challenges occur with needs for improved hardness for scuff and abrasion resistance, particularly in the UV cured OEM flooring market, according to Rich Edgar, end use manager, wood and coil markets, BYK USA, Inc. "Newer developments in nanomaterials can offer enhanced mechanical resistance over traditional alumina, such as BYK's Nanobyk line of alumina oxide based nanomaterials," he said. "Key challenges with nanomaterials, particularly in wood flooring, include high transparency needs, as well the relative higher costs of raw materials over traditional products.
"Other additive options include newer developments in harder and tougher wax alloys that combine excellent scratch and mar resistance with gloss reduction," Edgar continued. "The wax alloy type products, as with BYK's Ceraflour 928 and 988, are micronized amide modified polythylene waxes capable of superior mar and abrasion resistance in both waterborne UV and solventborne 100% solids UV cure applications."
Scratch and mar resistance for automotive clear coats also continues to be an important area of technology development within UV/EB coatings. "With the increased interest in the use of waterborne UV in coatings application, the need for efficient dewatering and evaporation of water from the coating is very important," said Tina Snider, market development manager, resins, BASF North America. "Eco-friendly solutions include changes to equipment such as light sources for light emitting diode (LED). This requires fine tuning of molecules to meet the limitations of such systems, including molecules that lead to less odor and generate less migratory species."
According to Snider, BASF is investing in core pigment, dispersant and photoinitiator technologies to help customers achieve performance and sustainability objectives in several areas, including special pigments for heat and light management and vacuum metalized pigments that produce brilliant new color effects; photoinitiator-bound resins for hot melt adhesives that are compliant with EPA guidelines and help deliver higher performance without sacrificing cost; light stabilizers for waterborne UV coatings; waterborne dispersants and resins that are more efficient in delivering both functionality and beauty for UV/EB coatings and inks; and lastly, waterborne UV coatings and resins with additives and photoinitiators for improved adhesion and outdoor durability.
Evonik recently introduced a new matting agent specially formulated for the UV-cured coatings market. The range of matting agents Evonik offers now includs EXP 3600. This silica-based matting agent is suited for use in UV-cured coatings due to its special surface configuration. It is characterized by high transparency, low residual gloss, excellent surface quality and its scratch-resistance properties. Part of Evonik's Acematt range of matting agent products that have been on the market and popular with paint and coatings manufacturers for many years now, EXP 3600 is easy to incorporate and it does not negatively impact the coating system's other application properties in any way, according to the company.
Coatings manufacturers are also hard at work on the product development front. Ecology Coatings has developed bio-based materials for use in a new family of EcoQuik UV-curable coatings. Products incorporating bio-based additives are being used in commercial development applications that exhibit enhanced curing speed, pigment coverage and useful surface effects.
A bio-based material is simply a product derived from living matter. A good example is casein-A phosphoprotein, a material extracted from milk and then processed in various ways for use in plastic, dietary supplements, glue, cotton candy, protective coatings and paints, according to Ecology Coatings.
In 2007 DSM Desotech, a business unit of DSM Resins and part of Royal DSM N.V., launched its UVention group, dedicated to the formulation of custom UV/EB curable coatings for a wide variety of industries. Since that time, two new business areas have been added to the UVention portfolio: UVolve Instant Floor Coatings and UVaCorr anti-corrosion coatings for tube and pipe applications.
Most recently, DSM Desotech expanded its UVaCorr instant-cure, corrosion preventative coatings to Europe's steel tube and pipe market. The UVaCorr product line, which has been used for the past 15 years throughout North America, includes both clear and colored coatings designed for protection of steel tube and pipe, particularly during storage and transport to end-use destinations.
Moving forward chemists will continue to look toward developing greener and safer coatings. "There is now a significant push toward more sustainable materials and the formulators are turning to the raw material suppliers to provide them," said Chemark's Palermo. "A major challenge to overcome is the need for raw material suppliers to continue to innovate in an environment of cut-backs. Additionally, shortages of raw materials and higher prices associated with them will create potential formulation cost increases potentially harming the conversion rates to radiation technologies as was the case with the acrylic acid shortage."
Global specialty chemicals supplier Cognis has signed an agreement that it intends to sell its UV acrylates business to IGM Resins B.V., based in Waalwijk, The Netherlands. The UV acrylates business is part of Cognis' Functional Products strategic business unit. The sale is expected to be formally completed by June 2010. The UV acrylates business manufactures and sells monomers and oligomers for UV applications marketed under the Photomer brand name. The sale of the UV acrylates business includes the Photomer trademarks, intellectual property, inventory, and the Charlotte manufacturing site in the U.S. The manufacturing employees at this site will be transferred to the new owner, as well as several business related employees in the U.S., France and Asia.
"We firmly believe that we have found a growing and entrepreneurial player in the global UV acrylates business that is in the position to develop the business successfully and enabling a more comprehensive product offering for the customers," said Paul Allen, executive vice president, Cognis Functional Products. "We will work closely together with IGM Resins to ensure a smooth transition of the business."