Patent GB-729739-A (GB)
Title: Improvements in or relating to the manufacture of materials with adhesive coatings
IPC: C09J7/21
Filed: 1951-09-26
Abstract: A heat-activatable coating composition comprises, in uniform mixture, finely-divided, individual particles of two different heat-activatable components, namely, component (a) obtained by cooling a homogeneous fusion of a resinous material with a major amount of a solid plasticizer, e.g. an amount greater than the maximum amount permanently compatible with the resinous material at room temperature, and component (b), which is the same or a different resinous material or the product obtained by cooling a homogeneous fusion of resinous material with a minor amount of plasticizer, the resinous materials and plasticizers being such that, when the mixture is heated to fusion temperature, its particles coalesce to form a blend having, thereafter, a softening temperature substantially lower than that of the original mixture. An aqueous coating composition may comprise, a dispersing-agent, a binder and an adhesive composition in which, component (a) amounts to 55 to 99, preferably 60 to 95, per cent by weight of the adhesive composition, and contains 70 to 95 parts by weight of crystalline plasticizer and 30 to 5 parts of resin, and component (b) contains 5 to 25 parts of crystalline plasticizer and 95 to 75 parts of resin.  The aqueous composition may contain separately prepared dispersions of components (a) and (b). Component (a) may be obtained by fusing diphenyl phthalate, indene resin and rosin derivatives at least partly soluble in alkali in the proportions 80 : 5 : 15 by weight, and component (b) may be obtained by fusing the same ingredients in the proportions 15 : 79 : 6.  Other suitable plasticizers are:-acetanilide, dicyclohexyl phthalate, N-ethyl paratoluene sulphonamide, N-cyclohexyl paratoluene sulphonamide, meta-terphenyl, ortho-terphenyl and tri-(para tertiarybutyl phenyl) phosphate. Other suitable resinous materials are :-polyvinyl acetate, polystyrene of low molecular weight, kauri copal, mastic resin, sandarac resin, rosin, hydrogenated rosin, polymerized rosin, modified pentaerythritol ester of rosin, a pentaerythritol ester of polymerized rosin acids, an adduct of maleic anhydride and pentaerythritol ester of rosin or copal.  Suitable binders are:-animal glue, modified starch, dextrin, solubilized casein, solubilized soy protein, natural rubber latex, polystyrene of high molecular weight (about 80,000), polyvinyl alcohol and p styrene-butadiene, styrene-isoprene, butadiene-acrylonitrile, acrylonitrile-methyl acrylate copolymers.  Suitable dispersing agents are:-ammonia, lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, lauryl pyridinium chloride, the iso-octyl phenyl ether of polyethylene glycol and rosin soaps of ammonia, morpholine and ethanolamine.ALSO:A heat-activatable adhesive coating composition for paper, fibreboard, leather, cloth and films comprises, in uniform mixture, finely divided individual particles of two different solid heat-activatable components, namely, component (a) obtained by cooling a homogeneous fusion of a resinous material with a major amount of a solid plasticizer, e.g. an amount greater than the maximum amount permanently compatible with the resinous material at room temperature, and component (b), which is the same or a different resinous material or the product obtained by cooling a homogeneous fusion of resinous material with a minor amount of plasticizer, the resinous materials and plasticizers being such that, when the mixture is heated to fusion temperature, the particles coalesce to form a blend having thereafter a softening temperature substantially lower than that of the original mixture.  An aqueous coating liquid may contain a dispersing agent, a binder and an adhesive composition, in which component (a) amounts to 55 to 99, preferably 60 to 95, per cent by weight of the adhesive composition and contains 70 to 95 parts by weight of crystalline plasticizer and 30 to 5 parts of resin, and component (b) contains 5 to 25 parts of crystalline plasticizer and 95 to 75 parts of resin.  The aqueous coating liquid may contain separately prepared dispersions of components (a) and (b).  Component (a) may be obtained by fusing diphenyl phthalate, indene resin and rosin derivatives at least partly soluble in alkali in the proportions 80 : 5 : 15 by weight, and component (b) may be obtained by fusing the same ingredients in the proportions 15 : 79 : 6.  Other suitable plasticizers are:-Acetanilide, dicyclohexyl phthalate, N-ethyl paratoluene sulphonamide, N-cyclohexyl paratoluene sulphonamide, meta-terphenyl, ortho-terphenyl and tri-(para tertiary-butyl phenyl) phosphate. Other suitable resinous materials are:-Kauri copal, mastic resin, sandarac resin, rosin, polymerized rosin, hydrogenated rosin, glyceryl esters of rosin, polymerized rosin or copal, modified pentaerythritol ester of rosin, a pentaerythritol ester of polymerized rosin acids, an adduct of maleic anhydride and pentaerythritol ester of rosin, polyvinyl acetate and polystyrene of low molecular weight.  Suitable binders are:-Animal glue, modified starch, dextrin, solubilized casein, solubilized soy protein, natural rubber latex, polystyrene of high molecular weight (about 80,000), polyvinyl alcohol and styrene-butadiene' styrene-isoprene, butadiene-acrylonitrile, acrylonitrile-methyl acrylate copolymers. Suitable dispersing agents are:-Ammonia, lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, lauryl pyridinium chloride, the isooctyl phenyl ether of polyethylene glycol and rosin soaps of ammonia, morpholine and ethanolamine.