| 摘要 |
1359512 Pressure-sensitive record sheets KUREHA KAGAKU KOGYO KK 9 July 1971 [11 July 1970 2 Sept 1970 (2) 20 April 1971 (7)] 32424/71 Heading D2B [Also in Division C5] Copying paper is coated with a layer of microcapsules containing a dye composition comprising 100 p.b.w. of one or more alkyl naphthalenes of formula: wherein each R is C 1 -C 4 alkyl, n is 1-4, and the total number of alkyl C atoms is 4-6, 0-100 p.b.w. mineral oil, and 0.5-15 p.b.w. of a dye which is coloured under acid conditions. Suitable dyes are methyl or crystal violet, malachite green, rhodamine B, o-hydroxybenzalacetrophenone, or a derivative of Michler's hydrol, indole pyromellitate, or fluorane. The microcapsules may also contain inorganic or organic acidic materials such as bentonite, kaolin or other acid clays, zinc oxide, talc, silica, a zeolite, or an acidic polymer. Alternatively or in addition the acid developer may be coated on a further sheet of paper. In Examples coated sheets are prepared by conventional methods. |
