| 摘要 |
PROBLEM TO BE SOLVED: To provide an image display medium and an image forming device, which can form a color image by exposure to light, can rewrite images, are excellent in cycling test durability, and further, the formed image disappears by itself in a prescribed time regardless of existence of illumination source. SOLUTION: A photochromic composition contains a photochromic compound expressed by general formula (I) and a≥12C long-chain compound (wherein X is O, S or C(CH<SB>3</SB>)<SB>2</SB>; Y is absent or one selected from -CH<SB>2</SB>OCO-, -NHCO-, -O- or -OCO-; R<SB>1</SB>and R<SB>2</SB>are each a≥12C long-chain structure, and the carbon number of at least either is 17 or less; R<SB>3</SB>to R<SB>12</SB>are each hydrogen or a substituent group, where one among R<SB>3</SB>to R<SB>7</SB>is an electron-attracting group and one among R<SB>9</SB>to R<SB>12</SB>is an electron-donating group). COPYRIGHT: (C)2010,JPO&INPIT |
