| 摘要 |
1313170 Bonded fibre fabrics MONSANTO CO 28 Oct 1970 [29 Oct 1969] 51192/70 Headings D1R and D2B [Also in Division C3] Nonwoven fabrics are bonded with a copolymer of ethylene/vinyl chloride/acrylamide and/or acrylic acid. The acrylic acid is generated by hydrolysing the acrylamide groups in the copolymer with a strong acid or alkali. Preferably at least one additional polar unsaturated monomer is included in the copolymer. A list of such monomers is given. The binder may also contain up to 50% urea-formaldehyde, urea-ethylene formaldehyde or melamine formaldehyde. The nonwoven fabric is made from one or more of the listed natural or synthetic fibres by air-laying with the application of suction, carding or garnetting to give an orientated web, which may be crosslaid, wet laying or spun bonding. The binder, which may be concentrated near the surfaces of the fabric, may be applied to the fibres in powder or as a dispersion before they are air laid, or the formed mat may be sprayed with or dipped into an aqueous dispersion of 5 to 90% copolymer, which may also contain sodium dioctylsuccinate as wetting agent and sodium oleate for foaming or octyl alcohol or a silicone antifoaming agent. The binder may contain as crosslinking agent sulphur, or compound which liberate sulphur on heating specified in U.S. 3356658, namely bis (dimethylthiocarbamoyl) disulphide and tetrasulphide, dipentamethylene tetrasulphide, 4, 4' dithiodimorpholine, alkyl phenolsulphides, sulphur chloride, hydrogen sulphide or sulphur thiocyamide. The product contains 2 to 200% by weight of binder. It may be passed through a size press, heated to coalesce the binder, and calendered. |
