Improvements in or relating to self-manifolding sheet material

摘要

800,733. Ink. CARIBONUM, Ltd. June 15, 1956 [July 4, 1955], No. 19317/55. Drawings to Specification. Class 146(3) [Also in Groups VIII and XVI] In self manifolding sheet record material of the kind having on one side a colourless dye-stuff coating which is adapted to be transferred to the receptive surface of another sheet containing substances adapted to convert the dye stuff into its coloured form, the colour is prevented from fading or bleaching by providing in the receptive surface a substance which forms a lake with the coloured dye stuff. Lake forming substances specified are phosphotungstic acid, tungstic acid, phosphomolybdic acid, phospho-tungsto-molybdic acid, phosphosilicic acid, and their alkali metal salts. The tungstic acids are preferably applied in admixture with hydroscopic substances, e.g, glycerol, glycols and sorbitol, and in presence of methyl ethyl cellulose mixed if desired with barytes, precipitated calcium carbonate, blanc fixe and like finely divided material. Colourless dye stuff bases specified are bases, lactones or ethers of triphenylmethane dyestuffs. The receptive surface may comprise merely a roll of paper having an acidity of pH5-3.3 and the lake forming coating is applied thereto from rolls immediately before use. In examples, a colour forming solution consisting of nine parts 4, 41-(tetraethyldiamino) benzhydrol, nine parts sextol phthalate and 83 parts mineral oil was mixed with an emulsion consisting of 63 parts gelatine, 50 parts precipitated CaCO 3 , 170 parts water, seven parts anhydrous Na 2 CO 3 and 12 parts TiO 2 , and the mixture applied to a barrier coated paper by spraying, etc.; the ethyl ether of Setoglaucine may replace the benzhydrol. Acid coatings specified are mixtures of the following compositions: (1) 60 parts dextrin, 288 parts blanc fixe, 180 parts water; (2) 30 parts tannic acid, 42 parts dibutyl tartrate; (3) five parts phosphotungstic acid, 10 parts water. Specifications 700,109, 704,061, [both in Group VIII], 712,216 and 198,396 are referred to.