GB557182A - Improvements in the manufacture and treatment of paper and paper-forming materials - Google Patents

Abstract

557,182. Paper made from chemically treated, resin-containing pulp. TOOTAL BROADHURST LEE CO., CORTEEN, H., FOULDS, R. P., MARSH, J. T., and WOOD, F. C. May 5, 1942, Nos. 6003/42 and 4470/43. ' [Class 96] Paper containing a synthetic resin, e.g. of urea, thiourea, phenols or their homolognes, cyanamide, di-cyanamide, or melamine, condensed with formaldehyde, or vinyl products, or polymerization products of acrylic esters or methacrylic esters is subjected to a swelling agent, e.g. caustic soda or potash, alone or with carbon bisulphide, carbon oxysulphide, ethylene oxide, or dimethyl sulphate; or cuprammonium hydroxide, strong organic bases, strong acids, zinc chloride, or sulphocyanides, under conditions which would mercerize cellulose. Up to 10 per cent. of. the synthetic resin may be present and may be added to pulp, or after partial or complete drying to paper, as uncondensed components or as first stage crystalline components, and subsequently hardened, or as further (non- crystallizing) condensation products, whereupon the paper may be glazed, embossed, corrugated, creped, or crinkled or mechanically treated, heated to condense the resin, and preferably washed using, e.g. a dilute solution of a wetting agent and soda ash, swollen; e.g. using 65‹ t w. caustic soda for 15 minutes and allowed to shrink transversely and longitudinally. The products have high wet and dry strength and high absorbency and may be impregnated with resinous constituents, aqueous emulsions, dispersions or solutions; they may be laminated, or made into string or yarn. Specification 437,441, [Group IV], is referred to.