Patent GB-1123013-A (GB)
Title: Coated polyalkylene film
IPC: C08J7/052
Filed: 1965-06-11
Abstract: Surface oxidized polyalkylene film is coated with a substantially unbranched alkyd resin having free hydroxyl groups and a M.W. above 2000 cross-linked with sufficient of a poly-(alkoxymethyl)aminoplast to provide 1 to 2 alkoxymethyl groups per alkyd hydroxy group. A non-tacky vinylidene chloride copolymer, dyes, pigments and U.V. absorbers may be uniformly distributed in the coating which may be applied as an acid-catalysed aqueous solution or emulsion of the unreacted alkyd and aminoplast followed by heating to effect cross-linking to the toluene insoluble but fusible state.  In examples the alkyds are derived from various combinations of the following reactants: tetrahydrophthalic anhydride, adipic acid, dimerized linoleic acid, tetrapropanyl succinic anhydride, fumaric acid, sebacic acid, neopentyl glycol, trimethylolethane, pentanediol, polyethylene oxides M.W. 1450 and 300, diethylene glycol and glycerol; and specified aminoplasts are hexakis (methoxymethylmelamine), tris(methoxymethyl) trimethylmelamine, di(methoxymethyl) urea, 2,5-(dimethoxymethyl) uron, tetrakis(methoxymethyl)stearoguanamine, N,N1 - di(methoxymethyl) adipamide, tris(methoxymethyl) tris(4,6-diamino-s-triazine-2-ylamino) ethyl phosphine oxide, and tris(methoxymethyl) adipamide.ALSO:Surface oxidised polyalkylene film is coated with a substantially unbranched alkyd resin having free hydroxyl groups and a M.W. above 2000 cross-linked with sufficient of a poly (alkoxymethyl) aminoplast to provide 1 to 2 alkoxymethyl groups per alkyd hydroxy group.  A non-tacky vinylidene chloride copolymer, dyes, pigments and U-V absorbers may be uniformly distributed in the coating which may be applied, e.g. by air knife, doctor blade, offset roll or gravure roll, as an acid-catalysed aqueous solution or emulsion of the unreacted alkyd and aminoplast followed by heating to effect cross-linking to the toluene insoluble but fusible state.  The base film may be polyethylene or polypropylene oxidised by corona discharge, an oxidising flame or oxidising solutions such as chromic acid.  The coating may be a top-coating, rendering the film heat-sealable or it may be a tie-coating which is either completely reacted to the toluene-insoluble form with the top coat applied as a solution, emulsion or melt or incompletely reacted to a toluene-soluble, tacky form with the top coat material applied as a sheet or film followed by heating to complete the reaction. Specified top-coats are printing ink, nitrocellulose lacquer, butylated urea-formaldehyde lacquer, mucilage, vinylidene chloride copolymers, e.g. with acrylonitrile, methyl methacrylate or vinyl acetate.  In examples the alkyds are derived from various combinations of the following reactants:- tetrahydrophthalic anhydride, adipic acid, dimerised linoleic acid tetrapropanyl succinic anhydride, funaric acid, sebacic acid, neopentyl glycol, trimethylolethane, pentanedrol, polyethylene oxides M.W. 1450 and 300, diethylene glycol and glycerol; and specified aminoplasts are hexakis (methoxymethylmelamine), tris(methoxymethyl) trimethylmelamine, di(methoxymethyl) urea, 2,5-(dimethoxymethyl) uron, tetrakis(methoxymethyl) stearoguonamine, N,N1-di(methoxymethyl) adipamide, tris (methoxymethyl) tris(4,6-diamino-s-triazine-2-ylamino) ethyl phosphine oxide, and tris(methoxy-methyl) adipamide.