| 摘要 |
<p>666,437. Carbon papers. NATIONAL CASH REGISTER CO. June 17, 1949 [July 31, 1948], No. 16153/49. Drawings to Specification. Class 100 (iv). [Also in Groups VIII and XV] A sensitized record sheet, a plurality of which are used in a manifold assembly comprises a base sheet having on the front surface thereof a coating containing particles of an absorbent substance and on the rear surface a pressure rupturable coating having entrapped therein droplets containing an adsorbate substance which is colour reactive with the absorbent substance to produce a distinctive colour, the pressure rupturable coating being ruptured under pressure from a printing or typing machine to release the entrapped droplets from the surface of the rear coating to contact with the absorbent contiguous surface of the next sheet. The absorbent surface comprises a coating of attapulgite or like clay or a sodium aluminium zoolite the Na base exchange cations of which have been replaced by cations of Ni, Cu, Fe, Zn, Hg, Ba, Pb, Cd, and the compounds giving colour reactions therewith are Crystal Violet, Malachite Green &c. lactones having formulµ 3.3-bis-(p-dimethylaminophenyl- 6-dimethylamino phthalide 3.3-bis(p-d-methylaminophenyl) phthalide 3.3-bis-(p-dimethylaminophenyl)-4.5.6.7.-tetrachloro phthalide 2.4.-bis (p-dimethylaminophenylazo)-anilino)-6-hydroxy symtriazine. The transfer coating is made by dissolving 1 pt gelatine having an isoelectric point of pH 8 and a jelly strength of 275 gms (Bloom Gelometer) in 3 pts water and into 4 pts of this solution there are dispersed 3 pts of a solution of crystal violet lactone mixed with an equal part of bis-(p-dimethylaminophenyl) methane as methylene base. The solution of lactone and methylene base is made by dissolving 1-¢ pts of the lactone and base in 97 pts chlorinated diphenyl having a chlorine content of 48 per cent. The emulsion is applied at a temperature of 150‹ F. to the paper and is dried by hot air and is then treated to drive the droplets into the interior of the film and form a dry skin thereover by wetting the surface with water containing 1 per cent formaldehyde and 0.1 per cent wetting agent, e.g. dioctyl ester of Na succinate. In making the receiving surface the paper is coated with a mixture comprising 20 per cent starch which has been cooked in water at 200‹ F., and 4 pts attapulgite dispersion (1 pt attapulgite to 3 pts water). A mixture of starch, casein and butadiene styrene copolymer may replace the starch. Specifications 629,165, [Group VIII], and 666,438 are referred to.</p> |
