| 摘要 |
<p>876,037. Faced hardboard. ABITIBI POWER & PAPER CO. Ltd. Sept. 18, 1959 [Sept. 22, 1958; Aug. 13, 1959], No. 31913/59. Class 96. Paper e.g. lightweight tissue paper, is coated on one surface with a pigment, e.g. rutile or anatase titanium dioxide, zinc oxide, zinc sulphide, barium sulphate, calcium sulphate, lithopone, calcium carbonate, talc, clay or diatomaceous earth, a binder, e.g. polyvinyl alcohol, carboxymethyl cellulose, starch or modified starch, preferably chlorinated starch blended with a styrene-butadiene latex, casein, soya bean protein, urea-, or melamine-formaldehyde, acrylic, vinyl, or polyolefin resins, cellulose esters &c., and dispersing agents, e.g. sodium silicate, hexametaphosphate, pyro- or tetra phosphate, cationic wetting agents, &c., e.g. by air-knife coating, roll coating, blade coating, or brush coating &c., and dried, and may be waxed, printed, or super-calendered &c., an adhesive, e.g. a thermosetting or thermoplastic resin, or linseed, soya bean, tall or tung oil, may be applied, e.g. with phenolic, urea, vinyl or alkyd resins or butadiene-styrene latex and the adhesive-treated side is applied to a hardboard wetlap of dewatered coarse-fibrous wood pulp, and the two-ply material subjected to heat and pressure, e.g. 650 p.s.i. at 330‹ F. for 13 mins., baked, and humidified. A firm bond between the two plies is thus obtained, due to the lignins, hemicelluloses and other natural binding materials of the wood, and-may be supplemented by the drying oil. Silicones, ammonium, zinc or aluminium stearate or oleic acid may be used to avoid sticking in the press. Specification 753,028 is referred to.</p> |
