| 摘要 |
<p>1291737 Backing carpets E I DU PONT DE NEMOURS & CO 29 April 1970 [29 April 1969 10 April 1970] 20702/70 Heading B2E [Also in Divisions B5 and Dl] Carpets are made by applying to a tufted fabric a solution, dispersion or melt having a viscosity of 2,-2000 cps of precoat adhesive which is solid at room temperature and subsequently applying a hot melt adhesive composition. A secondary scrim may be adhered thereto (see Division B5). The pre-coat adhesive may comprise starch, casein, rosin derivatives, waxes or homopolymers or copolymers of olefins, compounds containing a vinyl group, esters having olefinic unsaturation amides, a wide variety of suitable polymers being specified. The hot melt adhesive composition preferably has an application viscosity of 5000-50,000 cps and is suitably a polyethylene, a copolymer of ethylene with vinyl acetate, acrylates or methacrylates or compositions described in Specification 1249611. Fillers, waxes and extenders may also be incorporated. In an embodiment a tufted structure 10 is drawn over a roll 14 dipping in a reservoir of a pre-coat adhesive and then contacted with a coating roll dipping in a reservoir of the hot melt composition. Rolls above the coating roll ensure good contact and the thickness of the coating is controlled by a doctor blade. The adhesive is cooled and the carpet is passed to a tenter frame and cooler. The tufted fabric suitably comprises nylon or polypropylene fibres in a jute or polypropylene backing.</p> |
