Patent GB-1065416-A (GB)
Title: Improvements in and relating to stiffening
IPC: C08F251/02
Filed: 1964-04-10
Abstract: Aqueous dispersions of copolymers of vinyl esters with unsaturated monocarboxylic acids or unsaturated dicarboxylic acids or half-esters thereof, containing as protective colloid 0.5 to 7% by weight of the copolymer of a water-soluble copolymer of acrylamide and an N-alkyl acrylamide having 2 to 6 carbon atoms in the alkyl group or water-soluble cellulose derivative may be prepared by polymerizing the monomers in aqueous dispersion in the presence of the protective colloid, optionally together with an emulsifying agent.  Specified monomers are vinyl acetate, propionate and butyrate; acrylic, methacrylic and crotonic acids; and maleic, fumaric and itaconic acids and the half-esters thereof.  Specified emulsifying agents are fatty alcohol sulphates, fatty alcohol polyglycol ethers and esters thereof with sulphuric and phosphoric acids.  The dispersions may be used for stiffening textile materials.  In examples: (1) vinyl acetate and crotonic acid are copolymerized in aqueous dispersion in the presence of a copolymer of acrylamide and N-t.-butyl acrylamide, sodium lauryl sulphate, coconut fatty alcohol polyglycol ether phosphate, potassium persulphate, sodium sulphite and sodium bicarbonate; (2) vinyl acetate and monobutyl maleate are copolymerized in the presence of a copolymer of acrylamide and N-t.-butyl acrylamide, sodium lauryl sulphate, coconut fatty alcohol polyglycol ether phosphate, potassium persulphate, sodium sulphite and sodium bicarbonate; and (3) vinyl acetate and crotonic acid are copolymerized in the presence of hydroxyethyl cellulose, sodium lauryl sulphate, coconut fatty alcohol polyglycol ether potassium persulphate and sodium sulphite.ALSO:Textiles are provided with a stiffening finish that is stable to neutral washing agents but soluble in alkaline washing agents by treating with aqueous dispersions of copolymers prepared from a vinyl ester and a mono-or dicarboxylic acid or half ester thereof, said dispersions containing as protective colloid 0.5 to 7 per cent by weight of the copolymer of a water soluble copolymer of acrylamide with an N-alkyl acrylamide in which the alkyl group contains 2 to 6 carbon atoms or a water soluble hydroxyethyl cellulose, said dispersions being free from vinyl copolymers containing free hydroxyl group.  The textile material may be immersed in the dispersion, which may also contain emulsifiers, fillers, ironing assistants and optical brighteners.  Specified vinyl esters are vinyl acetate, propionate and butyrate; and specified acidic comonomers are acrylic, methacrylic and crotonic acids; and maleic, fumaric and itaconic acids and the half esters thereof.  In examples (1) linen and cotton fabrics are treated with aqueous dispersions comprising a vinyl acetate/crotonic acid copolymer and an acrylamide/N-t-butyl acrylamide copolymer, (2) cotton fabrics are treated with aqueous dispersions comprising a vinyl acetate/monobutyl maleate copolymer and an acrylamide/N-t-butyl acrylamide copolymer, and (3) linen and cotton fabrics are treated with aqueous dispersions comprising a vinyl acetate/crotonic acid copolymer and hydroxyethyl cellulose.