| 摘要 |
PROBLEM TO BE SOLVED: To obtain a composition that shows a reversibly thermochromic behavior, in which a temperature increase upon heating in a decolored state is utilized as a trigger, and during the course of temperature fall after heating, it begins coloration, exhibits the maximum density of a developed color and is restored into a decolored state by using an electron-donating color-forming compound, an electron-accepting compound comprising an alkoxyphenol compound and a reaction medium as the essential components. SOLUTION: The electron-donating color-forming organic compound (A) used is conventionally known diphenylmethanphthalides, etc. The electron- accepting compound (B) used is represented by the formula (wherein R is an alkyl, desirably a 3-18C alkyl) and is exemplified by p-n-propyloxyphenol. The reaction medium (C) used to reversibly effect an electron transfer reaction in a specified temperature range is exemplified by an alcohol (e.g. decyl alcohol) or an ester. The mixing ratio among components A, B and C is 1/(0.1-50)/(5-100). The composition is used in the form of microcapsules. |
