| 摘要 |
1,190,981. Paper; non woven fabric. DEXTER CORP. 30 March, 1967 [18 April, 1966; 17 Feb., 1967], No. 14483/67. Headings D1R and D2B. An unshrunk non-woven fibrous structure is formed from a mixture of synthetic, organic, thermoplastic, cold-drawable fibres and a binder which consists of resins, synthetic resins, synthetic rubbers, conventional papermaking fibres or mixtures of conventional paper-making fibres with resins. synthetic resins or synthetic rubbers, and is bonded by a non-heatbonding process. The cold-drawable fibres are undrawn, have a substantially constant order of molecular orientation along individual fibre lengths, and an ultimate elongation of more than 200 per cent. They may be of polymers, such as polyamides, acrylics, polyethylene terephthalate, polyvinylidene chloride, polyethylene and polypropylene, and may be crimped or twisted. The sheet has good tear strength, and when it is torn the torn edges are bridged by the elongation of the previously undrawn fibres. The papermaking fibres may be a conventional cellulosic pulp, or mixtures of cellulosic fibres and drawn, man-made fibres of composition .the same as or different from that of the undrawn fibres, and may be beaten or unbeaten. The other binder, if any, may be applied uniformly or in spots. In the Examples: (1) kraft woodpulp is beaten and divided into two parts, drawn nylon fibres are added to one and undrawn "nylon fibres to the other, and the two then made into sheets; (2) kraft woodpulp is beaten, drawn and undrawn nylon fibres are added in varying proportions to portions of the pulp, sheets are made and dried and then impregnated with cross-linked polyvinyl alcohol and dried; (3) Example 2 is repeated, but butadiene-acrylonitrile latex is used in place of the polyvinyl alcohol; (4) Example 3 is repeated, but using an acrylic latex; (5) Example 4 is repeated, but using mixtures of drawn and undrawn nylon fibres in various proportions (6) webs are made by air-laying undrawn nylon fibres only and drawn nylon fibres only and bonded with the self-cross-linking acrylic latex of Example 4; (7) furnishes as in Example 1 contain an epichlorohydrin-polyamide wet-strength resin, are formed into sheets, dried and impregnated with the acrylic latex of Example 4; ,(8) kraft pulp is beaten and divided into two .parts, drawn polypropylene fibres are added to one and undrawn polypropylene fibres to the other, handsheets are made from both and treated with toluene solutions of an acrylic ester resin; and (9) Example 8 is repeated with polyester fibres in place of polypropylene. The materials may be used as base sheets for stencils, or for tapes, as interlinings, or as towels, wash cloths, wiping or dust cloths, headrest covers, table cloths, aprons, diapers, or disposable sheets, pillowcases and dressing gowns, as carpet backings, bookbindings, electric insulation, reinforcing layers for plastics film, imitation leather, clothing, aisle runners, tarpaulins, tents, curtains and draperies, upholstery, food wrapping, pipe wrappings, tea or coffee bags. |
