| 摘要 |
<p>829,674. Coated fibrous materials. DU PONT DE NEMOURS & CO., E. I. March 3, 1958 [March 21, 1957], No. 6806/58. Class 140. Sheet material suitable for use as a bookbinding material comprises a flexible fibrous substrate having on one side thereof a base coat comprising a vinyl chloride polymer and a copolymer of 113-butadiene and acrylonitrile, and a top coat comprising a vinyl chloride polymer, a drying oil modified alkyd resin and an aliphatic monohydric alcohol modified ureaformaldehyde resin. The base coat may comprise 85 to 15% of vinyl chloride polymer and 15 to 85% of butadiene-acrylonitrile copolymer, and the top coat may comprise 80 50% of vinyl chloride polymer, 15 to 30% of the modified alkyd resin, and 5 to 20% of the modified urea-formaldehyde resin, all proportions being by weight. The substrate which may be paper, or a tightly or loosely woven or non-woven, such as felted fabrics of natural or synthetic fibres, may be sized on the uncoated side with for example a polyvinyl acetate size as described in U.S.A. Specification 2,650,170. The expression "vinyl chloride polymer " means a polyvinyl chloride, or a copolymer of vinyl chloride and another ethylenically unsaturated monomer such as vinyl acetate, vinylidene chloride, vinyl fluoride, a C 1 to C 4 alkyl fumarate, and acrylic acid, the vinyl chloride constituting at least 50% of the copolymer. The butadiene-acrylonitrile copolymer may be that described in U.S.A. Specification 1,973,000. The aliphatic monohydric alcohol, e.g. butanol, modified ureaformaldehyde resins are described in Specification 483,399. Drying oil modified alkyd resin specified are derived from pentaerythritol, glycol, diethylene glycol and glycerine, with phthalic, terephthalic, adipic, succinic, and sebacic acids modified with linseed, chinawood or soya oils. Thickening agents, e.g. salts of polyacrylic resin, sodium carboxymethyl cellulose, starch or animal glue, fillers, e.g. china clay, calcium carbonate, titanium dioxide, pigments, stabilizers, e.g. dipropylene glycol dibenzoate, and the like may also be present.</p> |
