Microscopic Studies on Coating Film. II.

Film Thickness on Bended Edge

Abstract

It is well known that the painted film thickness on bended edge parts is thinner than any others, but there have been no reports studied systematically about it.
The authors attempt to examine the film thickness on bended edge parts by taking photograms of sections of paint films using a microscope and to explain about several factors which influence to the films on edge parts. The results are as follows :
1. The film thickness on bended edge parts was influenced greatly upon with forms of edge parts, especially in the case of a right angle was extremely thin.
2. Among the film thickness on edge parts of several paint types, Nitrocellulose Lacquer was the thickest. There was a few differences between both Amino Alkyd Enamel and Thermosetting Acrylic Enamel.
3. Influence of coating conditions upon the film thickness on edge parts by changed by paint types. In the case Nitrocellulose Lacquer, it was influenced greatly upon with temperature and air velocity. It was considered owing to evaporation ratio of solvents in paints and thinners.