Color-developing ink for leuco compound

Abstract

Abstract PURPOSE: To prepare the titled ink capable of developing a leuco compound to a color which dissapears gradually and completely with time to give an invisible record free from discoloration or color-developing, and suitable for a detector, toy, etc., by combining a specific compound containing a phenolic hydroxy group and a non-volatile tertiary amine. CONSTITUTION: The objective ink can be obtained by mixing (A) a sublimable or volatile compound having a phenolic hydroxyl group of formula I (R 1 WR 5 are H, halogen, carboxyl, nitro, methoxy, phenyl, 1W3C hydroxyalkyl or 1W9C alkyl) or formula II (e.g. p-t-butylcresol, 1-naphthol, etc.) and (B) a non-volatile tertiary amine of formula R 6 R 7 R 8 N (R 6 WR 8 are 1W20C alkyl, phenyl or benzyl). The weight ratio of (A) to (B) is e.g. 5 to 1. The component (A) develops a colorless leuco compound, and the developed color dissapears gradually with the sublimation or evaporation of the component (A). COPYRIGHT: (C)1982,JPO&Japio

Inventors

• 👤 Koichi Ishii

Bibliographic Details