PARTICULES COMPOSEES SCELLABLES A CHAUD POUR DES TISSUS A INFUSION ET PROCEDE DE PREPARATION

摘要

1297749 Fibrillar assemblies DEXTER CORP 28 May 1971 [23 Sept 1970] 17883/71 Heading B5B [Also in Division D2] A random, water-dispersible matrix comprising an attenuated fibrilliform thermoplastic resin carrier in which are embedded granules (e.g. 25-75% by wt. based on the carrier) of a second, incompatible, thermoplastic resin, the whole being incapable on its own of forming a self-supporting waterleaf, is made by dispersing the granules in a solution of the carrier resin and effecting precipitation of the whole under shearing conditions. The product, of which at least 90% may pass through a 35 mesh screen is useful as a heat-sealing additive to paper-making fibres at the wet end of a papermaking machine. In examples, granules of polyethylene of average diameter 100 Á are dispersed in an acetone solution of a vinyl chloride/vinyl acetate copolymer and precipitated with aqueous acetone below 25‹ C. The paper may exhibit a concentration gradient of the additive across its thickness.