| 摘要 |
1,148,720. Polyurethane articles. CARL FREUDENBERG. 20 July, 1966 [20 July, 1965; 4 Sept., 1965; 28 Oct., 1965], No. 32624/66. Heading B5A. [Also in Division C3] Articles having a body of foamed polyurethane and at least a part of its surface a non- foamed layer integral therewith are made by introducing the foam-forming materials into a mould having available on at least part of its internal surface, a cross-linking catalyst for polyurethane, and foaming so that the foam produced is under superatmospheric pressure. The mould surface may be of metal with a release agent coating or fluorinated hydrocarbon to which cross-linking catalyst is applied before each moulding operation, or at least part of the surface may be silicone rubber, e.g. cold cured silicone rubber which itself provides the cross-linking catalyst. The catalyst applied may be an organo-tin soap. |
