Carbonless copying paper prodn. - by coating acceptor sheet with pore sealant, drying and coating with acid adsorbent

摘要

In the prodn. of press.-sensitive colour reaction copying paper with a donor sheet having microcapsules and an acid adsorbent material on the acceptor sheet, coating is carried out in 2 stages. In the first stage, a subbing with development properties, which seals the pores of the paper, is applied, then the material is dried before applying the acid material. Thin acceptor coatings can be produced economically and continuously on small units. These coatings give copies of great colour intensity and stability. The pore sealant can be a novolak, zinc blende, tannin or conventional binder resins, dissolved in alcoholic and/or similar solvents. For the second stage, the compsn. contains a conventional acid adsorbent and also resin and solvent, but less than for the first coating.