Patent GB-820145-A (GB)
Title: Pvc copolymer/polyurethane primers for vinyl resin coatings
IPC: D06M15/263
Filed: 1957-10-08
Abstract: Primer compositions, which are used to coat metals (e.g tinplate) or nylon or polyacrylonitrile cloth with polyvinyl resin compositions, comprise (i) a polymethane and (ii) a copolymer of vinyl chloride, a carboxylic ester of vinyl alcohol and maleic acid or anhydride.  The polymethanes (i) may be derived from polyalkylene glycols, e.g. polyethylene glycols of M.W. 400-600, polypropylene glycols or mixtures, and diisocyanates, e.g. 2,4-tolylene-, 2,6-tolylene (or mixtures thereof), 3,31-dimethyl-4,41-bephenylene-, 3,31-dimethoxy, 4,41-biphenylene-, 4,41-diphenyl-methane-, or 4,41-methylene di-o-tolyl-diisocyanates.  The terpolymer (ii) may be derived from vinyl acetate, and preferably from vinyl esters of saturated fatty acids in which the alkyl radical attached to the carboxyl group contains 1-6 C.  Suitable solvents for the primer compositions (i) + (ii) are blends of aromatic hydrocarbons (e.g. toluene) with ketones (e.g. acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone), ethyl acetate or tetrahydrofuran.  Top coat compositions disclosed are (A) PVC, whiting, TiO2, 2-ethyl hexyl diphenyl phosphate and di(2-ethyl hexyl) sebacate; (B) a vinyl chloride/vinyl acetate copolymer, di-2-ethyl hexyl phthalate, diisobutyl ketone, petroleum solvent, with or without TiO2; and (c) a vinyl chloride/vinyl acetate copolymer, toluene and methyl isobutyl ketone.  The primers are baked after application; the top coats may be applied as plastisols, and subsequently heated.ALSO:Cloths, e.g. of nylon or polyacrylonitrile, are impregnated by dip, roller or knife coating, or by spraying, with a primer composition comprising (i) a polyurethane and (ii) a copolymer of vinyl chloride, a carboxylic ester of vinyl alcohol and maleic acid or anhydride.  The polyurethanes (i) may be derived from polyalkylene glycols and di-isocyanates.  The terpolymer (ii) may be derived from vinyl acetate or from another vinyl ester of a saturated fatty acid in which the alkyl radical attached to the carboxyl group contains 1-6 carbon atoms.  Suitable solvents for the primer composition (i) + (ii) are blends of aromatic hydrocarbons (e.g. toluene) with ketones (e.g. acetone, methyl ethyl ketone, methyl-isobutyl ketone or cyclohexanone), ethyl acetate or tetrahydrofuran.ALSO:Primer compositions comprise (i) a polyurethane and (ii) a copolymer of vinyl chloride, a carboxylic ester of vinyl alcohol and maleic acid or maleic anhydride.  The polyurethanes (i) may be derived from polyalkylene glycols, e.g. polyethylene glycols of M.W. 400-600, polypropylene glycols or mixtures, and diisocyanates, e.g. 2,6-tolylene, 2,4-tolylene- (or mixtures thereof), 3,31-dimethyl-4,41-biphenylene-, 3,31 - dimethoxy - 4,41 - biphenylene-, 4,41 - diphenylmethane- or 4,41 - methylene-di-o-tolyl-diisocyanates.  They may be prepared in the presence of aromatic hydrocarbons, esters such as ethyl acetate, chlorinated solvents, and ketones such as methyl ethyl-, methyl isobutyl-ketone, and cyclohexanone.  The terpolymer (ii) may be derived from vinyl acetate, and preferably from vinyl esters of saturated fatty acids in which the alkyl radical attached to the carboxyl group contains 1-6 C.  Suitable solvents for the primer composition (i) and (ii) are blends of aromatic hydrocarbons (e.g. toluene) with ketones (e.g. acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone), ethyl acetate or tetrahydrofuran. The primer compositions are used to coat metals (e.g. tinplate) or nylon or polyacrylonitrile cloth with P.V.C. compositions.  The following top coat compositions are disclosed: (A) P.V.C., whiting, TiO2, 2-ethyl hexyl diphenyl phosphate and di-(2-ethyl-hexyl) sebacate; (B) a vinyl chloride/vinyl acetate copolymer, di-2-ethyl hexyl phthalate, diisobutyl ketone, petroleum solvent with or without TiO2; (C) a vinyl chloride/vinyl acetate copolymer, toluene and methyl isobutyl ketone.