| 摘要 |
1,245,079. Colour-reactive copying paper.- FUJI PHOTO FILM CO. Ltd. 5 Dec., 1969 [10 Dec., 1968], No. 59549/69. Heading D2B. [Also in Division C2] A pressure-sensitive copying paper comprises a support having coated thereon a layer of micro capsules containing a solution in an organic solvent of a compound of general formula: (in which n is 1-4, R 1 and R 2 each denote alkyl (C 1-4 ) or phenyl; R 3 is hydrogen, alkoxy (C 1-4 ), alkoxycarbonyl (C 1-4 ), alkyl (C 1-4 ), or halogen) said compound causing a colourforming reaction with an electron-acceptive material, particularly an electron-acceptive solid acid or salt, which may also be coated on the support, or on an adjacent, lower, sheet. Specified solid acids and salts include acid clay, Japanese active clay, attapulgite, zeolite, kaolin, bentonite, silica gel, aluminium sulphate, felspar, pyrophyllite, halloysite, magnesium trisilicate, zinc sulphate, calcium fluoride and citrate, tannic and benzoic acid. Preferred colour formates (which give a red colour) are 1-#-carboxyethyl-3,3-dimethyl-spiro (indoline -2, 2'-2'-H-#-naphthopyran) and its 5-methyl and 5-chloro derivatives. |
