GB778798A - Improvements in pressure-sensitive adhesive sheeting - Google Patents

Abstract

778,798. Pressure sensitive adhesive tapes; flexible laminates. UNITED STATES RUBBER CO. Feb. 29, 1956 [June 6, 1955], No. 6289/56. Class 140. A pressure sensitive adhesive sheet comprises a backing laminate composed of a film of polyethylene 1 reinforced with a plurality, e.g. 10 to 70 yarns per inch width of tape, of spaced parallel glass fibre yarns 2 which may extend longitudinally parallel to the edges of the tape, each of said yarns being completely surrounded by and in direct and intimate contact with the polyethylene of said film and may be disposed more closely to one face than to the other of said film of polyethylene, said first named face having longitudinally extending protuberances formed by the yarns and polyethylene above said yarns, and valleys formed between said protuberances the lowermost points of the valleys being substantially below the uppermost points of the yarns, and having on one face of the laminate a water. insoluble normally tacky and pressure sensitive adhesive of the rubber resin type 3. With reference to Figs. 2 and 3, glass fibre yarns 2, spaced by comb 17, are continuously fed into the nip formed by polyethylene films 12 and 14, extruded at an elevated temperature from extruders 11 and 13, at roll 16 and resiliently surfaced roll 15, cooled and coated by the action of doctor knife 19 behind which bank 18 of adhesive is maintained, prior to drying in zone 20 and winding on roll 21. Suitable adhesives are vinyl alkyl ether polymers or copolymers of two or more monomeric alkyl acrylates or a mixture of a natural or synthetic rubber or a rubbery material, e.g. GR-S, polyisobutylene, reclaimed natural or synthetic rubber, and a natural or synthetic tackifying resin, e.g. ethylene glycol ester of hydrogenated rosin, factice (vulcanized vegetable oil).