Patent GB-1072341-A (GB)
Title: Improvements in manifolding papers and systems
IPC: B41C1/10
Filed: 1964-05-06
Abstract: A manifolding system comprises a base sheet having a transfer coating on one side, and a base sheet having a receptor coating on one side in contact with the transfer coating.  The transfer coating comprises a pigment of finely divided inorganic platelets bound together and to the base sheet by an adhesive in amount between 2 and 15% by weight of the platelets, the adhesive containing at least 20% of a synthetic resin, and having a glass-transition temperature below 40 DEG C.  The receptor coating comprises a soft synthetic-resin or cellulose ester adhesive, has a glass-transition temperature below 40 DEG C and is applied at a coat weight so low that it is not tacky to the touch, and does not block when rolled.  Platelet pigments referred to are clays and talc.  Other pigments, e.g. of needle, cubical or spherical types may also be present, as also may thermoplastic organic pigments such as polystyrene.  The bases for both coatings may be coated or uncoated papers or films of synthetic plastics.  The transfer coating may also contain colouring materials, such as carbon black, red oxide, chromium oxide, phthalocyanine pigments or water-soluble dyes. The receptor coating too may contain a small amount of pigments, e.g. titanium dioxide or calcium carbonate. The transfer coating can be calendered or supercalendered after application.  When making a planographic plate with a planographic coating on one side and a transfer coating on the other, both coatings can be applied before calendering.  The adhesive of the transfer coating may include a proportion of hard material.  Suitable soft adhesives with glass-transition temperatures below 40 DEG C are polymers of butadiene, isoprene, dimethyl-butadiene, isobutylene, ethyl, n-propyl, n-butyl, n-octyl, n-tetradecyl, n-hexadecyl, isobutyl or 2-ethylhexyl acrylate, propyl, n-hexyl, n-octyl, n-decyl or n-tetradecyl methacrylate, ethylene glycol isobutyrate methacrylate and vinyl acetate, and polyurethane rubber.  Other adhesives with a glass-transition temperature above 40 DEG C can be treated with plasticizing agents so that the adhesive as a whole has a glass-transition temperature below 40 DEG C.  Examples are polymers of acrylic acid, acrylonitrile, terbutyl acrylate, methyl, isopropyl or tertbutyl methacrylate, polyethylene glycol dimethacrylate, polyethylene glycol terephthalate, polyvinyl p  alcohol, polyvinyl butyral, polyvinyl chloride-acetate and polyvinylpyrrolidone, cellulose acetate and cellulose nitrate. Also used in the Examples are: a styrene-butadiene copolymer, butyl rubber and polyterpene resin, a self-cross-linking acrylic polymer ("Rhoplex M-3") a vinyl acetate copolymer plasticised with butyl benzyl phthalate, polystyrene, "Rhoplex AC33," "Rhoplex B-5" alone or with the styrene-butadiene copolymer, and mixtures of styrene-butadiene copolymer with a styrene-maleic anhydride copolymer or a vinyl methyl ethermaleic anhydride copolymer.  Paper may be coated with the transfer coating on one side and the receptor coating on the other, cut into sheets and superposed.  The receptor coatings can be printed upon.