Autostereotypic Printing: A New Swiss Reproduction Process
A New process of so-called autostereotypic printing, especially adapted for the reproduction of books and engravings, has lately been invented in Switzerland, and is already used with advantage in a large printing office at Zurich. The process will cheapen the reprinting of the works of foreign authors, since the typesetting and copying of engravings are saved, and an accurate stereotype plate is obtained directly from the original. It is a transfer process, in which a blank, composed of plaster of paris, silicate of potash or soda, and phosphate of lime is employed. The print to be copied is moistened in a solution of phosphate of soda in distilled water, alcohol and acetic ether, and then transferred in the usual way on the plaster of paris plate, previously coated with a film of gelatine containing citrate of iron and ammonia. After the transfer (all the process thus far having been conducted in a dark room), the plate is dried and exposed to direct sunlight for fifteen minutes. When taken out, the place acted upon by the light will be found to be quite hard, while at the other places the plaster will be soft, and will fall off as fine powder as deep as the solution shall have penetrated, if brushed with a hard brush. The plate will then be ready to be stereotyped.—Christian at Work.