PURPOSE: To further increase the content of nitroxy free radicals in the photochromic photosensitive material contg. the nitroxy free radicals and to improve its light resistance characteristics by adding ≥2 kinds of the nitroxy free radicals which are triplet extinction agents in addition to a spiro-oxadine compd. to a high-polymer material.
CONSTITUTION: Two or more kinds of the nitroxy free radicals which are the triplet extinction agents are added in addition to the spiro-oxadine compd. into the high polymer. The high-polymer material to be used may be any high- polymer materials, insofar as these materials have good compatibility with the spiro-oxadine compd. and the nitroxy free radicals, are optically transparent and have excellent film formability. The solubility is greatly improved and the phenomenon of deposition after coating is not admitted by using ≥2 kinds of the nitroxy free radicals in combination in such a manner. In addition, the phenomenon that the deteriorated material by photoirradiation is formed by the such phenomenon and that the photosensitive material discolors to red is further prevented and the light resistance is greatly improved.
MAEDA SHUICHI
MITSUHASHI KAZUO
NAKAMURA SHINICHIRO
MITSUBISHI CHEM IND