Light deterioration control by generation of self-defensive substance and light stabilization additive

Piling suiting thin films of poly(phenylene ether) (PPE) and polycarbonate (FC) was used to examine the light deterioration behavior. Monochromatic li ght irradiation with an Okazaki National Research Institutes of National In stitute for Basic Biology Large Spectrograph (OLS) and white light irradiat ion with a xenon tube were used for this experiment. The results showed tha t the light deterioration occurred only at the surface layer. The self-defe nsive reaction which generated a quinone-methide in the deterioration defen ded the light deterioration. When the irradiated sample was put in a solven t, the products from the quinone-methide might be in both the solution and insoluble portion. The coloring of PPE and PC hardly decreased on addition of a light stabilization additive. The deterioration could be suppressed mo re in the absence of additives. This implies that the control of the light deterioration affected the self-defensive reaction.