Procédé de fabrication de filtres de cigarettes, et appareil pour sa mise en oeuvre

摘要

1,131,919. Non-woven fabrics; forming web. HONSHU SEISHI K.K. 28 April, 1966 [12 May, 1965 (2); 11 June, 1965; 5 July, 1965; 6 July, 1965; 28 Jan., 1966; 25 March, 1966], No. 18783/66. Headings DIN and D1R. A dry process for making a non-woven fabric comprises defibring a natural fibre, synthetic fibre or mixture thereof, blowing the defibred fibres against a screen in a jet of air, so that single fibres pass through the screen while flocks are retained on the screen, drawing the screened fibres on to a first travelling wire-net conveyer by suction to form a non- woven web, transferring the web to a second endless wire-net conveyer, spraying adhesive on to the exposed surface of the web, drying, transferring the web to a third wire-net conveyer, a portion of which faces and runs parallel to the second, spraying adhesive on to the unsprayed surface of the web and drying. As shown, a web of bleached sulphite pulp from a roll 1 is fed between corrugated rolls 2 to two hammer mills 4 and 5 and blown by a fan 6 along a duct 9. Across the end of the duct are a travelling, endless screen belt 13 of about 10 mesh and a travelling, small-mesh wire-net conveyer 18. Flocks of fibres caught on the screen belt 13 are carried downwards to a suction box 14 connected to a duct 15 to return the flocks to the hammer mill 4. A suction box 19 draws the fibres passing through the belt 13 on to the conveyer 18. The web so formed is transferred successively to further wire-net conveyers 21, 29 and 33 by means of suction boxes 22, 30 and 34 and a blower 24. The two sides of the web are sprayed with adhesive from sprayers 23 and 32 assisted by suction boxes 26 and 31 and dried in chambers 28 and 36. The product is wound at 37. The adhesive may be a solution or emulsion of a copolymer of vinyl acetate and an ester of acrylic or methacrylic acid, mixed with a cross-linking agent which is a vinyl monomer containing an amino, amido, methylol or carboxyl group.