GB1192351A - Method for the manufacture of Flexible Sheet Material - Google Patents

Abstract

1,192,351. Laminates. DUNLOP CO. Ltd. 9 Aug., 1966 [20 Aug., 1965], No. 35778/65. Addition to 989,433. Heading B5N. [Also in Division D1] A leather-like sheet material is manufactured by forming a mat of crimped continuous filaments, consolidating the mat in the presence of material affording a bonding agent, and pressing the mat of crimped continuous filaments into contact with an openwork net fabric during or subsequent to consolidation of the mat, the crimped continuous filaments having been subjected to tension and allowed to relax before the mat was consolidated. The mat of crimped continuous filaments may be formed by (a) plying together at least two separate layers of crimped continuous filaments which have been collected under tension; (b) collecting under tension, preferably substantially parallel, crimped continuous filaments to the desired depth which upon relaxation provide a mat of crimped filaments; or (c) drawing off a creel or beam an assembly of tensioned crimped continuous filaments to the desired depth, which are then relaxed to form a mat. The crimped continuous filaments may take the form of a stretch yarn treated by a torque twisting process, an edge crimped twistless yarn, or a chemically crimped yarn. Specified filaments are those made of nylon, polyethylene terephthalate, polyacrylonitrile, polyolefines, rayon and natural silk. The bonding agent may be a thermoplastic resinous or elastomeric binder preferably flexible at room temperature. It may be of a composite nature, i.e. there may be a first bonding composition which bonds the fibres simply at their crossing points and a second composition which extends more generally around the filaments. Specified elastomeric binders are polyurethane rubber, natural rubber, butyl rubber, rubbery styrene-butadiene copolymers, butadieneacrylonitrile copolymers and polychloroprene rubber. Polyolefines, e.g. polyethylene, are specified as suitable resinous binders. The binder(s) may contain curing agents and plasticizers. The consolidated mat may have a layer of polypropylene staple fibres needled to one or both faces thereof as described in Specification 1,042,028. Another form of consolidated mat may be as described in Specification 1,105,484. Preferably, the bonding agent is at least partially cured prior to pressing the mat into contact with the open-work net fabric. This fabric may be of metal, e.g. steel, or a synthetic plastic material, e.g. polyethylene, and may have a diamond or rectangular, e.g. square, mesh structure. The pressing of the mat with the net fabric can be carried out at room temperature or at an elevated temperature. It may be carried out in a press, the plates of which may, if desired, be heated and the time of contact is from 5-20 seconds, preferably 10 seconds. Only one or both faces of the mat may be pressed with the net fabric. A face of the mat may be buffed prior to pressing with the net fabric and after the mat has been pressed with the net fabric and consolidated it may be dyed.