| 摘要 |
<p>1,180,938. Laminated structural unit. SOC. RHODIACETA. 4 May, 1967 [4 May, 1966], No. 20735/67. Heading B5N. [Also in Division D1] A structural unit, e.g. for use in walls or partitions, comprises one or more sheets formed of molecularly oriented organic continuous filaments arranged at random in a non-parallel manner throughout the or each sheet, the sheet or sheets being impregnated with a thermosetting resin. The filaments may be of polyethylene terephthalate, isotactic polypropylene, polycaproamide, polyhexamethylene adipamide, PVC, polyvinylidene chloride, cellulose acetate, polyacrylonitrile or polyvinyl alcohol and the impregnating resin may be a phenoplast or aminoplast. In one method of making the sheets, polyethylene terephthalate is extruded as filaments from a spinneret and advanced by means of a drawing injector nozzle supplied with compressed air, the filaments being cooled during such advance. The bundle of filaments so formed is fed via a reciprocating guide on to a conveyer belt to form a non- woven sheet, which sheet is passed between heated calender rolls to bond the filaments where they cross. Two sheets formed as described, i.e. " spunbonded," are superposed and needled before impregnation with a solution of phenolformaldehyde resin in a mixture of alcohols. The impregnated sheet is allowed to dry, then dried under heat at one temperature before heating at a higher temperature to cure the resin. The resulting sheets are sound insulating, rot resistant and fireproof. In a second embodiment a structural unit comprises a core of rigid polyurethane foamed in situ between two of the impregnated sheets. An alternative unit comprises an undulating one of said sheets between two plane said sheets.</p> |
