Atmospheric Plasma Treatment
October 2015 www.coatingsworld.com Coatings World | 71
a “stock” UV powder coating and standard plasma lab system.
Since it is common practice to tweak the powder chemistry or
fine-tune the plasma settings to optimize adhesion, we consider
these results even more illuminating. The fact that the majority
of powder/substrate combinations showed robust evidence that
good results are possible without much fuss. In three of the four
cases plasma treatment made the difference between an acceptable and unacceptable process.
Certainly follow up work can focus on testing with variants of
the powder coating, and different surface treatment parameters to
improve the adhesion of UV powder coating both to these substrates,
and to other popular plastics such as SMC, BMC, and Nylon.
This article shows how atmospheric plasma treatment
can overcome adhesion failures commonly associated with
UV liquid and powder coatings to plastic. Our testing also
suggests that plasma surface treatment may offer a robust
solution to applying a wide selection UV powder to a number of common plastics.
Our initial results provide evidence that plasma treatment
yields acceptable results on otherwise un-coatable surfaces.
Plasma offers a safe, cost-efficient, and environmentally friendly
means for improving the performance of both liquid and powder UV coatings for a growing range of plastic applications. CW
This paper was originally presented at the 2nd Biennial
Eastern Coatings Show, June 1-4 in Atlantic City, New Jersey.
Acknowledgements
The authors wish to thank Kevin Biller, and the research staff
at the Powder Coating Research Group, Columbus, Ohio for
their expertise, help and dedication to this project.
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Figure 3 The Effects of Plasma Surface Treatment on Polypropylene
