GB377176A - Improvements relating to manifolding documents, drawings, addresses and the like - Google Patents

Abstract

377,176. Printing. RITZERFELD, W., 107, Liitzowstrasse, Berlin. March 16, 1931, No. 8013. [Class 100 (ii).] Copying documents, drawings, and the like; printing-surfaces; printing processes.-In a process for copying documents, drawings, addresses, &c., as described, for instance, in Specification 311,330, [Class 100 (ii), Printing processes &c.], in which an original sheet bearing a mirror copy in hectograph ink on the back is utilized to print copies on to moistened copy sheets, the moistening liquid consists mainly of alcohol, to which are added one or more solvents, such as benzol, toluol, or benzyl alcohol, and one or more plasticizers, such as glycerine or phthalic acid ester ; the added substances reduce the ink-dissolving action of the alcohol and therefore increase the number of copies produced. A specific example comprises methylated spirit, benzol, benzyl alcohol, glycerine, and diethyl ester of phthalic acid. The efficiency of the process is further increased by the employment of particular materials for the original and copy sheets. The original is written or typewritten on paper which is not thin, but is very soft and smooth, and, preferably, is heavily loaded with chalk, e.g., art printing paper or chromo paper, whereby the characters stand out in relief on the reverse side of the paper and therefore print more clearly and the ink is not absorbed by the paper but remains on the surface ; also, paper of this kind resists tearing or cutting by the stylus or typewriter. The copy sheets are made of very cloudy, non-translucent, semiglazed, non-absorbent paper containing but little wood cellulose, such as machine glazed paper, which by resisting penetration below its surface absorbs very little ink and liquid.