Patent GB-763453-A (GB)
Title: Improvements in or relating to coated web products and method of forming same
IPC: D04H13/00
Filed: 1953-10-09
Abstract: 763,453. Resin-coated webs; resin-bonded fibrous webs; laminated materials. KIMBERLEY-CLARK CORPORATION. Oct. 9, 1953 [Oct. 11, 1952], No. 27808/53. Class 140. A web product composed of filaments has a surface coating of a thermoplastic waterinsensitive resin partially fused with a compatible plasticizer which was initially applied as a dispersion of the resin and the plasticizer having a viscosity 2,900-16,000 centipoises, the coating being bonded to at least a portion of the surface of the web without substantial impregnation of the filaments of the web. By partially fused is meant that the resin is not completely solvated in the plasticizer. Resins may be polyvinylchloride or vinylchloride-vinylacetate copolymer. Plasticizers may be dioctyl phthalate, dioctyl sebacate, polyethylene glycol di-(2- ethyl hexoate) or mixtures of these. Partially hydrogenated mixtures of isomeric terphenyls may be included. The resins may be used as plastisols or organosols with admixture of organic solvents, e.g. diisobutyl ketone, xylene, or naphtha. A preferred composition is 54-58 parts polyvinylchloride and 42-46 parts dioctyl phthalate, although other compositions are exemplified. A woven gauze, Fig. 1, has deposits of dispersion along discrete areas 4a at alternate intersections of threads 2, 3 with consequent bonding of the threads and at 4b along length of lengthwise threads 2. A light density, e.g. 1.5 grams/sq. yd., applique of non-woven cotton fibres 5, <SP>1</SP>/ 16 th-3 in. long, is secured by the dispersion. The web, Fig. 2, is taken from supply roll 6 under applicator roll 8 fed with dispersion from reservoir 9 under doctor blade 11. The viscosity of the dispersion is preferably 4,000-7,000 cps. and deposits as shown in Fig. 1, are obtained by driving applicator roll 8 at a slower speed (196 ft./min.) than the gauze travel (200 ft./min.) so that dispersion is scraped off particularly by cross threads 3 and also deposited on lengthwise threads 2. If roll 8 is rotated at a greater speed than the gauze travel the deposited areas will be reversed. The coated gauze passes over heating roll 12 at 240-295‹ F., preferably 280-295‹ F. to partially fuse the dispersion and may be wound up for storage or passed directly to the fibre depositing means. A bat of non-woven fibres 5a is fed to divellicating roll 13 to build up a refined bat 5c on moving belt 14 having associated suction box 15. The bat 5c is fed to second divellicating roll 16 and the resultant stream of fibres 5d deposited on to dispersion coated web 1 assisted by suction box 17. The web is fed round rolls 18 (which may be heated) and 23 against heated steel roll 21 at 265-320‹ F. which co-operates with resilient calender roll 19 to press the fibres into the dispersion which is softened. During calendering the threads of the gauze web are flattened also. Depending on the use heavier fibre layers may be deposited and the second divellicating unit may be dispensed with. The dispersion may be subsequently completely fused by passing the web through an oven, with some consequent impregnation of the gauze threads, 10-25 per cent by weight of dispersion should be used if it is only partly fused and 50 per cent or more if completely fused. It is stated that the dispersion may be applied to woven, knitted or non-woven carded webs by spraying, brushing, dipping, printing or indirectly by applying threads or bundles of threads which have been coated with partially fused dispersion. Fig. 5 (not shown), shows a carded web of fibres with spaced lines of dispersion. Non-woven webs carrying the partially fused dispersion may be assembled as laminates and calendered for further fusion. Specification 703,345 is referred to.