LOW-VISCOSE, MICROCAPSULES AND BINDERS CONTAINING AQUEOUS COATING AND PRINTING COLORS, PAPER PRINTED AND COATED WITH THESE COLORS, AND THEIR USE IN PRINT-SENSITIVE COPYING SYSTEMS.

摘要

1. Stable aqueous printing inks and coating compositions of low viscosity containing microcapsules and binders, comprising, in addition to auxiliaries usually used in aqueous printing inks and coating compositions, (a) a water-miscible solvent or solvent mixture having a boiling point of =100 degrees C, and (b) microcapsules having a mean diameter of from 1 to 8 mu m which are obtained by condensation of melamine and formaldehyde or melamine/formaldehyde precondensates in an aqueous dispersion of the solid or liquid, essentially water-insoluble phase forming the core, in an aqueous solution of a homopolymer or copolymer containing sulphonic acid groups, at a pH of from 3 to 6.5 and a temperature of from 20 to 100 degrees C, the molar ratio of melamine to formaldehyde being from 1 : 1.5 to 1 : 6, and the ratio of resin to core material being from 1 : 13 to 1 : 2, and the polymer containing sulphonic acid groups, which is free from phenyl and/or sulphophenyl groups, having a K value according to Fikentscher of from 100 to 170 or a viscosity of from 200 to 5000 mPas at a shear gradient of 489 s**-1 in 20% strength by weight aqueous solution at 25 degrees C.