Patent ID: 8444450

Claim:
A method for alternately expressing a color-memorizing photochromic function in a toy element, which comprises arranging (1) a color-changing means under a contacted or non-contacted condition, which contains at least one of an ultraviolet ray absorbent and a light-shading pigment capable of shading at least ultraviolet rays, to (2) a toy element comprising a photochromic layer which maintains a coloring state by developing a color through the irradiation of ultraviolet rays or sunlight containing ultraviolet rays and changes into decolorizing state through its decolorization by the irradiation of visible light, wherein the coloring state is visible in well-lighted areas, wherein said color-changing means changes said photochromic layer of the coloring state into decolorizing state by cutting off ultraviolet rays of sunlight and thereby effecting irradiation of visible light, and maintains the changed state, and wherein said photochromic layer contains a diaryl ethene photochromic compound, so as to express a function to memorize and maintain coloring and decolorizing states alternately.