| abstract |
NEW MATERIAL:Fluoran compounds of formula I wherein R is methyl, ethyl. n EXAMPLE: 3-N-n-Propylmethylamino-6-methyl-7-phenylaminofluoran. n USE: Chromogen which develops a black color and is used for color-forming recording materials such as thermal recording paper, pressure-sensitive copying paper, etc. (color density at low temp. of 90W100°C is high). n PREPARATION: A benzoic acid derivative of formula II is reacted with a 4-hydroxy-(or 4-lower alkoxy)-2-methyldiphenylamine of formula III (wherein R' is H. lower alkyl) in a molar ratio of 1:1 in sulfuric acid. n COPYRIGHT: (C)1984,JPO&Japio |