Outdoor-exposure testing of painted coating and the weathering factors involved.

概要

論文の詳細を見る
Outdoor exposure tests were carried out on four kinds of resin coatings on steel (polyester, acrylic, polyurethane and melamine) for one year at five locations in Japan-Asahikawa, Tsukuba, Tokyo, Choshi and Naha-and the relationships between the physical-chemical changes on the surfaces of the films and weather factors were evaluated. It was found that polyester resins did not deteriorate under the tests but that the acrylic, polyurethane and melamine resin specimens showed chalking, discoloration and decrease of gloss retention. The degree of deterioration differed in accordance with the test site. Deterioration was minimal at Asahikawa, which is located in the north of Japan, but was marked at Naha in the south. Occurrence of the -CO radical and increases in the amount of oxygen on the deteriorated surfaces of the acrylic resin were noticed. It was found that air temperature and humidity affected the deterioration of the films, but the product of mean air temerature and mean absolute humidity showed the effect on the deterioration more clearly than the individual values. While it was found that air temperature, humidity, precipitation and ultraviolet rays all were factors in the deterioration of the films, the correlation between the individual factors and film deterioration was low, and it was assumed that film deterioration was caused by the synergistic effect of all the factors.
社団法人表面技術協会の論文