Sunblock and radical scavengers
UV light causes some components of any coating to age through the production of radicals. These highly reactive molecules attack the paint coat. In addition, UV rays and heat promote radical formation in conjunction with ozone and air humidity. There is also the gradual oxidation caused by atmospheric oxygen. Therefore, in addition to UV absorbers, the new coating specially developed for CFRP surfaces contains free radical scavengers—molecules that neutralize radicals.
However, processing hydroprimers places complicated demands on the production equipment, making it more expensive. “In China, the hydro process is not yet established as a technical standard,” explains Georg Bussmann, Director of International Technology Management at Wörwag. It was therefore necessary to find an alternative for the Chinese Action Composites factory that would meet the high quality demands of the customer and the paint specialists.
The developers in Stuttgart-Zuffenhausen presented the results in no time: Instead of a hydroprimer, an organically dissolved adhesion promoter is used. This has two advantages for the factory in China. On one hand, there is a greater variability in layer thickness than with the hydro counterpart. On the other hand, work steps are considerably fewer, which reduces the process costs.
“In China, the hydro process is not yet established as a technical standard,” explains Georg Bussmann.
From auto parts to sports equipment
The idea to use the CFRP coat in industrial applications besides the car industry was a result of the very positive results achieved with it. Demand was identified at a trade fair in China for manufacturers of high quality sports equipment.
Joanne Wang, Sales Manager at Wörwag in Langfang was charged with the marketing. She is also the contact person for Action Composites. “Given the broad spectrum of applications outside of automotive engineering, we are collaborating with an external marketing company that knows this market,” explains Wang.
First contacts have been made. Wörwag has one more trick up its sleeve: if the carbon doesn’t necessarily have to be visible, for example in sports rowing boats or skis, Stuttgart offers primers with special colour effects. The season has begun.
Text: Thorsten Schönfeld
Illustration: Star Worbs