| 摘要 |
PURPOSE:The titled composition that contains a specific nitrospirothiopyran compound and a polymeric substance, thus being used as a medium for recording and regenerating with a semiconductor laser, because it is capable of developing colors at room temperature and shows high light absorption in long wave- length (more than 700nm) ranges. CONSTITUTION:The objective composition is obtained by using a compound of formula I (R1 is H, halogen, 1-5C alkyl, 1-5C alkoxy, nitro, cyano; R2 is 1-10C alkyl) such as 1',3',3'-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2'-indoline], preferably 5-30wt%, and a polymeric substance such as vinyl chloride- vinylidene chloride copolymer. The compound of formula I is obtained by reaction between 1-alkyl-3,3-dimethyl-5-substituted-2-methyleneindoline of formula IIand 5-nitrothiosalicylaldehyde of formula III. The irradiation with long wave- length light of more than 500nm makes the compound of formula I colorless and permits the compound to be used repeatedly.
|
