| 摘要 |
<p>980,757. Laminates. E. I. DU PONT DE NEMOURS & CO. July 19, 1962 [July 28, 1961], No. 27883/62. Heading B5N. An opaque polyvinyl fluoride film, the surface of which has been treated to make it capable of bonding to an adhesive, is laminated to a waterresistant, backing sheet by coating both the film and the backing sheet with an adhesive and passing them through nip rolls, the roll next to the film being cold and the roll next to the backing sheet being heated, and then passing the resulting laminate through cold nip rolls. The roll next to the backing sheet is heated to 60-70‹ C. The polyvinyl fluoride film may be biaxially-oriented and contains up to 30% by weight of a pigment, e.g. titanium dioxide, lamp black, chrome yellow, cadmium selenide red, phthalocyanine blue or phthalocyanine green so that it is opaque at least to ultra-violet light. Suitable backing materials are asphalt saturated felt and non-woven glass fibre mat, neoprene impregnated asbestos felt or rubber sheeting and suitable adhesives are butadiene-acrylonitrile copolymers or an asphaltic aqueous emulsion. The laminate may be used as a roofing material or as an outer covering for an insulated pipe. Specifications 845,634, 936,398 and U.S.A. Specification 2,673,826 are referred to.</p> |
