PURPOSE: To obtain the title material maintaining light resistance even by repetition of coloring and decoloring and continuous light irradiation, by making a composition wherein an organic photochromic compound is dissolved or dispersed into a hindered amine-based compound into microcapsules.

CONSTITUTION: A composition wherein (A) 1 pt.wt. organic photochromic compound such as 1,3,3-trimethylspiro [indolino-2,3'-(3H)naphtho(2,1-b)(1,4)-oxazine] is dissolved or dispersed in (B) ≥5 pts.wt. (preferably 10-50 pts.wt.) hindered amine-based compound such as bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate is made into microcapsules to give the objective material.