VERFAHREN ZUR HERSTELLUNG EINES DRUCKEMPFINDLICHEN KOHLEFREIEN KOPIERBLATTES UNTER EINSATZ VON MIKROKAPSELN, DIE IN EINEM DURCH STRAHLUNG ERHAERTETEN BINDEMITTEL ORTSFEST GEBILDET SIND

摘要

A process is provided for the production of a coating composition containing microcapsules having a hydrophilic core for use in the manufacture of pressure-sensitive carbonless transfer papers comprising the following steps. A hydrophilic emulsion component is prepared by dispersing at least one chromogenic material being soluble in the hydrophilic liquid. A hydrophobic emulsion component is prepared by dispersing an emulsifier in a radiation curable hydrophobic liquid. A first wall-forming material and a second wall-forming materialare added to the hydrophobic emulsion component, with mixing. The first and second wall-forming materials are soluble in the hydrophobic emulsion component,and the first wall-forming material is reactive with the second wall-forming material to form a polymeric capsule wall. The resultant polymeric capsule wallis substantially insoluble in the hydrophilic and the hydrophobic emulsion com-ponents. The hydrophobic emulsion component is mixed together with the hydrophilic emulsion component to form an emulsion containing droplets of the hydrophilic emulsion component dispersed in the hydrophobic emulsion component. Mixing is maintained for a period of time sufficient to allow the first and second wall-forming materials to react to form a dispersion of microcapsules in the hydrophobic emulsion component. The formed microcapsules have capsule walls substan-tially impermeable to the hydrophobic and the hydrophilic emulsion components. Pressure-sensitive carbonless transfer paper may be produced by applying the dispersion of the microcapsules prepared as above to a substrate, and curingthe dispersion by subjecting the dispersion on the substrate to radiation for a period of time sufficient to cure the radiation curable hydrophobic liquid, thereby producing a tack-free, resinous film on the substrate.