IE35668B1 - Tobacco smoke filter - Google Patents

Abstract

1318113 Tobacco smoke filters CIGARETTE COMPONENTS Ltd 30 Sept 1971 [1 Oct 1970] 24831/70 Heading A2C A rod of fibres or filaments, e.g. crimped filaments of cellulose acetate, bonded to each other at their points of contact is formed with a cavity extending from its surface at each of at least two longitudinally spaced positions, longitudinally adjacent cavities being circumferentially displaced relatively to one another, and is enclosed by a tubular member, e.g. of stiff paper. As shown, a pair of diametrically opposite cavities 10, 11 and 16, 17 each tapering towards the rod axis, is formed at each of two longitudinally spaced positions along the rod. These positions may be sufficiently close together that a plane normal to the rod axis intersects both pairs of cavities. The surfaces of the ends 18, 19 of the rod and the region 6 between the two pairs of cavities are preferably adhered to the tubular enclosing member 7. The filter may be attached to a tobacco rod 1 by a piece of cork tipping paper 4. Instead of a pair of cavities at each position there may be a group of four, or a single cavity extending beyond the rod axis. Apparatus is described in which crimped cellulose acetate filaments are sprayed with glyceryl triacetate and formed into continuous cylindrical rod which is then deformed locally by heated, toothed wheels to provide the cavities. The rod is then passed through a garniture where it is enclosed in a paper wrapper and finally cut into multiple-length filter rods. [GB1318113A]