GB1220464A - Improvements in the production of a fibrous web of non-woven fabric - Google Patents

Abstract

1,220,464. Papermaking. PAPETERIES NAVARRE. 20 Feb., 1968 [28 Feb., 1967], No. 8273/68. Heading D2A. A fibrous web of non-woven fabric is made from a dilute suspension of fibres in a device comprising a tank (1) with two convergent wall sections (7, 8) formed respectively by an endless belt (2) and a permeable endless surface (3) both leading to an outlet between parallel sections (9, 10) and means upstream of the outlet separately operable to create a vacuum in or to feed fluid to each of a plurality of compartments (16) on the outer face of the permeable surface, the wall sections being operable to draw the agglomerated fibres into the outlet and feed them to the parallel sections to form the web. As shown, the endless belt 3 is of metal or plastics cloth or felt and runs over rollers 12 and 13 of which one imparts drive. Roller 13 may have an internal suction chest, and cleaning elements 14A and smoothing elements 14B may be provided, 15 is a perforated displaceable face plate over the compartments 16. A narrow laminar jet 17 of air or water may serve to rearrange the fibres or create areas of reduced density, e.g. hinge areas. Suction boxes 18, steam distributors 19 and compressed-air distributors 20 may be provided, the last to reach the web from the belt 3. The endless belt 2 is of metal or plastics cloth or woven or knitted felt, or may be more or less liquid-proof. It may be driven separately from but synchronously with the belt 3, or by contact, through the web, between belts 2 and 3. The roller 11 may be solid or a dandy roll. In a modification, an internal partition 24 serves as a baffle to lay some of the fibres across the plane of formation of the web. In another modification a layer of wires, netting or screen of canvas of textile or metallic material or a meshwork fabric is incorporated in the web. It may be introduced between the walls 6 and 8 or 5 and 7 or through the inside of the tank as shown at 25. In other embodiments the endless surface 3 is a metal cloth on a drum-shaped frame (fig. 2, not shown), or wall sections 7 and 8 form a V-shaped trough with the outlet at the bottom (fig. 3, not shown).