| 摘要 |
<p>1335563 Coated products PECHINEY UGINE KUHLMANN 29 Oct 1970 [30 Oct 1969] 51339/70 Heading B2E [Also in Division B5] A process for the preparation of a composite material comprises simultaneously applying to a non-adherent support, a liquid polycondensate containing free NCO groups and either a liquid hardener or a hardener in solution in an inert solvent; then applying a layer of fibres on the layer thus obtained before total hardening; then simultaneously applying to the layer of fibres a liquid polycondensate containing free NCO groups and either a liquid hardener or a hardener in solution in an inert organic solvent, then applying a second layer of fibres on the layer thus obtained before complete hardening and finally separating the material so produced from the non-adherent support. In a preferred embodiment the application of the polycondensate and the hardener and the application of the fibres are repeated until the desired thickness is obtained. The non-adherent support may be of siliconised paper, siliconised metal, a silicone elastomer or polyethylene and may be smooth, grained or in the form of a negative of a leather surface. The polycondensate may be a polyurethane or a polyurethane-polyurea. The hardener is preferably a diamine. The polycondensate and the hardener may be applied by a curtain coater, a doctor or a roller by spraying. The fibrous layers which may be applied as divided fibres and/or fibrous sheets may comprise leather or natural or synthetic textile fibres, e.g. polyamide fibres, the fibrous sheets being preferably teased woven, knitted, non-woven or plush fabrics. The products may be scrapped, dyed and coated with nitro cellulose.</p> |
