Patent GB-1044998-A (GB)
Title: Improvements relating to coating compositions
IPC: C08L27/08
Filed: 1965-07-16
Abstract: Coating compositions comprise by weight 50 to 100 parts of a vinyl chloride homopolymer; 10 to 50 parts of a copolymer of 35 to 96.5 weight per cent of vinylidene chloride, 0.5 to 25 weight per cent of an acidic ethylenic compound and 3 to 40 weight per cent of at least one polymerizable monoolefinic monomer; 10 to 30 parts of a first plasticizer having a melting point below 40 DEG  C.; 5 to 15 parts of a second plasticizer having a melting point above 40 DEG  C., each of said plasticizers is an ester of phthalic, phosphoric, citric or 2-acyl citric acid wherein the acyl group has 2 to 4 carbon atoms, the alcohol or phenol residue of each ester group having up to 12 carbon atoms and being alkyl, cycloalkyl or aryl; 0.5 to 10 parts wax and 0.1 to 1 part of a particulate antiblocking agent. Specified acidic comonomers are itaconic, acrylic, methacrylic, citraconic, mesaconic and aconitic acids. Specified other comonomers are acrylonitrile, methacrylonitrile, acrylic and methacrylic esters, methyl vinyl ketone, vinyl acetate and vinyl chloride.  Specified first plasticizers are dibutyl, di-(methylcyclohexyl) and butyl benzyl phthalates, diphenyl 2-ethylhexyl phosphate, and triethyl, tributyl, acetyl tributyl and acetyl trioctyl citrates.  Specified second plasticizers are dicyclohexyl phthalate, tricyclohexyl and triphenyl phosphates, and tricyclohexyl citrate.  Specified waxes are paraffin, bees, palm, carnauba and ozocerite waxes, pentaerythritol tetrastearate, and long chain ketones and amides.  The waxes may be used together with blending resins, e.g. the glyceryl ester of maleic modified rosin, ester gum, rosinates, hydrogenated rosin and esters thereof and damar, copal, kauri and alkyd resins. The anti-blocking agent may be aluminium silicate clay, calcium silicate, mica or polystyrene. The compositions may be dissolved in solvents, e.g. benzene, toluene, xylene, tetrahydrofuran, acetone and methyl ethyl ketone, and used for coating hydrophilic organic polymeric materials, particularly regenerated cellulose film for use in packaging. Examples describe compositions comprising polyvinyl chloride, dibutyl and dicyclohexyl phthalates and (1,3 and 5) vinylidene chloride/acrylonitrile/itaconic acid copolymer, paraffin wax, glyceryl ester of maleic modified rosin, aluminium silicate clay, tetrahydrofuran and toluene; (2) a vinylidene chloride/methyl acrylate/itaconic acid copolymer, carnauba wax, mica and methyl ethyl ketone; and vinylidene chloride/methyl methacrylate/acrylonitrile/itaconic acid copolymers, aluminium silicate clay, tetrahydrofuran and toluene, together with (4) paraffin wax and glyceryl ester of maleic modified rosin and (6) stearamide.ALSO:Sheets, webs and films of hydrophilic organic polymeric materials may be coated with organic solvent solutions of compositions comprising by weight 50 to 100 parts of a vinyl chloride homopolymer; 10 to 50 parts of a copolymer of 35 to 96.5 per cent vinylidene chloride, 0.5 to 25 per cent of an acidic ethylenic compound and 3 to 40 per cent of at least one polymerizable monoolefinic monomer; 10 to 30 parts of a first plasticizer having a melting point below 40 DEG C; 5 to 15 parts of a second plasticizer having a melting point above 40 DEG C., each of said plasticizer being esters of phthalic, phosphoric, citric or 2-acyl citric acids wherein the acyl group has 2 to 4 carbon atoms, the alcohol or phenol residue of each ester group having up to 12 carbon atoms and being alkyl, cycloalkyl or aryl; 0.5 to 10 parts of wax and 0.1 to 1 part of a particulate antiblocking agent.  The compositions may be applied by doctor rolls, doctor knives or gravure rolls to films of regenerated cellulose, cellulose ester, cellulose ethers, polyvinyl alcohol, saponified ethylene-vinyl acetate copolymers and paper to give packaging materials.  Preferred copolymers are of vinylidene chloride and itaconic acid with acrylonitrile, methyl acrylate or methyl methacrylate.  Specified first plasticizers are dibutyl, di (methylcyclohexyl) and butyl benzyl phthalates, diphenyl 2-ethylhexyl phosphate, and triethyl, tributyl, acetyl tributyl and acetyl trioctyl citrates; and specified second plasticizers are dicyclohexyl phthalate, tricyclohexyl and triphenyl phosphates, and tricyclohexyl citrate.  Specified waxes are paraffin, bees, palm, carnauba and ozocerite waxes, pentaerythritol tetrastearate, ketones and amides; which may be used together with blending resins, e.g. modified rosins, ester gum and damar, copal, kauri and alkyd resins.  The antiblocking agent may be aluminium silicate clay, calcium silicate, mica or polystyrene.  In examples regenerated cellulose sheets containing (1 and 3 to 6) melamine/formaldehyde and (2) urea/formaldehyde anchoring resins are coated with compositions comprising polyvinyl chloride, dibutyl and dicyclohexyl phthalates and (1, 3 and 5) vinylidene chloride/acrylonitrile/itaconic acid copolymers, paraffin wax, glyceryl ester of maleic modified rosin, aluminium silicate clay, tetrahydrofuran and toluene; (2) a vinylidene chloride/methyl acrylate/itaconic acid copolymer, carnauba wax, mica and methyl ethyl ketone; and vinylidene chloride/methyl methacrylate/acrylonitrile/itaconic acid copolymers, aluminium silicate clay, tetrahydrofuran and toluene together with (4) paraffin wax and glyceryl ester of maleic modified rosin and (6) stearamide.