| 摘要 |
1278264 Coating IMPERIAL CHEMICAL INDUSTRIES Ltd 16 June 1969 [12 July 1968] 33363/68 Heading B2E Composite articles are made by applying, to a moving support surface having release properties, the ingredients for forming an impervious layer of polyurethane elastomer, applying to the layer a foam forming composition, allowing the foam to set and bond to the impervious layer and continously removing the composite from the release support. The release support may be embossed in order to impart a pattern to the impervious layer. The impervious layer may be applied as an emulsion or paste in a partly or fully polymerised state. The foam is preferably polyurethane formed in situ from a reaction mixture comprising polyether or polyester polyols, polyisocyanates, blowing agents, catalysts and surface active agents. The reaction mixture may be applied by blowing, spreading or spraying while the impervious layer is still only partially polymerised. The composite may be heated to accelerate the setting of the foam. In a modification, the polyurethane elastomer is transferred while still tacky from the support to a layer of fibrous material and the foam forming composition is then applied to the exposed polyurethane surface. |
