Patent GB-1020142-A (GB)
Title: Process for the production of non-woven fabrics
IPC: D04H1/425
Filed: 1964-10-09
Abstract: An emulsion used to impregnate paper and non-woven fabrics (see Division D1 and D2) comprises a copolymer of (a) one or more compounds of the formula <FORM:1020142/C3/1> where R2 is alkyl, cycloalkyl, aralkyl or aryl, and R1 is any of these or hydrogen, and (b) one or more other monomers of which at least one is a 1,3-diolefine or an ester of acrylic or methacrylic acid.  The copolymer can be made by polymerization in baulk, in solution or in emulsion, using conventional free-radical catalysts. In the examples, copolymers comprise: (1) and (3) 90% ethyl acrylate, 5% methacrylamide and 5% methyl methacrylamidomethylene-carbamate; (2) 87% butylacrylate, 5% methyl methacrylate, 3% methacrylamide and 5% ethyl methacrylamidomethylenecarbamate; (4) 80% butylacrylate, 12% acrylonitrile and 8% phenyl methacrylamidomethylenecarbamate; 40% butylacrylate, 40% ethylhexyl methacrylate, 10% acrylonitrile, 10% phenyl methacrylamidomethylenecarbamate; 60% butyl acrylate, 6.5% ethylhexyl methacrylate, 15% vinyl chloride, 15% vinyl acetate and 3.5% cyclohexyl methacylamidomethylenecarbamate; 70% ethyl acrylate, 24% ethylhexyl methacrylate and 6% cyclohexyl methacrylamidomethylenecarbamate; and (5) 77% butyl acrylate; 10% butadiene, 5% styrene, 3% methacrylamide and 5% ethyl methacrylamidomethylenecarbamate. In Example (5) the emulsion also contains a melamine-formaldehyde precondensate.ALSO:Non-woven fabrics are made from fibre webs by contacting them with an aqueous copolymer emulsion obtained by copolymerizing (a) one or more compounds of the formula:  <FORM:1020142/D1-D2/1> where R2 is alkyl, cycloalkyl, aralkyl or aryl and R1 is any of these or hydrogen, and (b) at least one other monomer, removing the excess of emulsion and drying at a temperature of 50 to 150 DEG C.  The compound of formula I may be the methyl, ethyl or butyl ester of acrylamidomethylenecarbamic acid, or the methyl or phenyl ester of methacrylamidomethylenecarbamic acid. The second monomer may be a diolefine such as 1, 3-butadiene, isoprene, 2-chlorobutadiene, or other conjugated diolefine of 4 to 6 carbon atoms, or an ester of acrylic acid with an alcohol of 1 to 20 carbon atoms, e.g. the methyl, ethyl, butyl, isobutyl, dodecyl or octadecyl ester, or an ester of methacrylic acid with an alcohol of 4 to 20 carbon atoms, e.g. the butyl, 2-ethylhexyl, dodecyl or octadecyl ester.  Further monomers may also be present, e.g. esters of methacrylic acid with alcohols containing 1 to 3 carbon atoms, vinyl acetate, propionate or benzoate, ethylene, propylene, vinyl chloride, dichlorethene, styrene, alpha-methyl-styrene, acrylic acid, methacrylic acid, or their amides or nitriles, 2-hydroxyethyl methacrylate, 2-aminoethyl methacrylate hydrochloride or 2-vinylpyridine.  The web may be made on a paper-making machine, or may be a cross-laid fleece produced on cards or by the air-lap system, or a tangled fibre fleece or felt.  The fibres may be made of wool, silk, natural cellulose, regenerated cellulose, cellulose acetate, regenerated protein, polyethylene terephthalate, condensation products of diamines and dicarboxylic acids, polymers of lactams, vinyl chloride-acetate copolymer, polypropylene, acrylonitrile polymers, polyurethanes, polyvinyl alcohol, glass, asbestos, metal or mixtures of the above.  Conventional auxiliary agents may be added to the emulsion, e.g. dyes, pigments, optical brighteners, emulsifiers, wetting agents, foaming agents, alginates, cellulose or starch ethers or esters, kaolin, bentonite, casein, polyvinyl alcohol, ammonium salts of polyacrylic acid, urea-formaldehyde resin, aminoplast or phenoplast precondensates, hardenable epoxy condensates, insecticides, fungicides, bactericides, age-resisters and adhesion-promoters.  The emulsion may be used over a wide range of pH, in the examples pH varies from 4 to 9.