Dr. Thimo Lothert from Axalta Coating Systems spoke at the Car Body Coating Intensive 2014 conference, in Leipzig, Germany. He presented insights into the challenges and complexities associated with plastic coatings in the automotive industry. With a history of more than 145 years in liquid and powder coatings, Axalta is well placed to comment on plastic coatings, and Dr. Lothert, Axalta Research Supervisor, has more than 16 years of experience in OEM coatings.

Coatings provide plastic automotive parts with aesthetically pleasing visual color effects – matte, high-gloss, pearl and metallic – and can also provide protection against premature mechanical or thermal failure. To achieve these objectives, plastic coatings from Axalta are designed to meet three specific and important criteria set by automotive OEMs. The first is color harmony – the coated plastic parts have to match perfectly with the rest of the vehicle. Secondly, the appearance of the plastic part, once coated, must also look comparable, in terms of flow and leveling, to the rest of the vehicle, with no imperfections such as excessive orange peel, pinholing or air bubbles. This can only be achieved through a specifically formulated coating composition for the end-use application process with the achievement of good flow for maximum appearance. And finally, technological durability is key. Plastic coatings have to demonstrate excellent adhesion, adequate scratch resistance and flexibility, and be capable of being cured at a lower temperatures to prevent damage to the the plastic substrate during bake cycles.

“Coatings for plastic substrates are increasingly relevant as there are more plastic parts on vehicles – from bumpers to spoilers and tail gates to door handles – and the size of those parts is increasing in view of plastic’s advantages over metals,” Dr. Lothert explained. “Plastic is lighter than metal and provides better durability than metal substrates. Plastic substrates are popular with designers, providing more options when presented with complex geometries. Overall, the flexibility, favorable performance in crash tests and lower cost makes plastic an extremely attractive substrate for car manufacturers.”

Axalta’s close cooperation over many decades with leading global car manufacturers has enabled the company to understand the challenges presented by plastic substrates, and has developed the coating systems to meet them.

“We strive to perform better every day so we collaborate closely with automobile manufacturers to develop better coating products for the vehicles of today and tomorrow,” explained Panos Kordomenos, Axalta’s Senior Vice President and Chief Technology Officer. “We know car manufacturers want to produce vehicles that are lighter, stronger and more fuel efficient, and which have parts made from a variety of materials other than metal, including composites and plastics. Axalta offers a wide range of coating systems and application technologies that address these needs, providing excellent protection and appearance.”

Not only can the coating systems from Axalta be used on the production line for plastic parts, but Axalta’s three global refinish brands – Cromax®, Spies Hecker® and Standox® – also supply cutting-edge refinish paint systems to body shops for the repair and refinishing of plastic parts for automotive aftermarket.

“Axalta’s depth and breadth of experience in coatings makes us a global leader,” concluded Dr. Lothert. “Our goal, therefore, is to fully integrate plastic coatings into the vehicle manufacturing process, optimizing the primer, basecoat and clear coat to deliver exactly what the car manufacturers need.”