To estimate the weatherability of the composite woods (these were treated with acryl high polymer) which were coated with polyurethane plastics paint and fluoroethylene plastics paint, these composite woods were weathered exteriorly for two years and were accelerated by weathering test machine during 1500 hours. Retention of gloss for the composite coated with polyurethane plastics paint (Polyurethane-Coated) linearly decreased with more than 500 hours but gradually decreased for the composites which were high degree of crosslinking. However, the retention of gloss for the specimens coated with fluoroethylene plastics paint (Fluoroethylene-Coated) were kept the initial gloss.
In weathered exteriorly, the degradation of Polyurethane-Coated occured in the beginning of the exposure and the retention of gloss decreased about 50% after 12th months but Fluoroethylene-Coated kept the retention of gloss of an initial stage. However Fluoroethylene Coated was observed that the paint was coming off and floating to the surface here and there. It was estimated that these phenomena were due to the decrease cohesion of copolymer from observations of repetition test for water absorption and dry and of flat adhesion test.

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