GB184128A - Improvements in rotary offset machines for printing fabrics - Google Patents

Abstract

184,128. Johnston, T. R. March 18, 1922. Rotary offset machines.-Webs of fabric are printed on one or both sides with a continuous design by means of intagliated copper cylinders, or by thin intagliated plates secured to cylinders, co-operating with rubber offset cylinders of a diameter equal to or an exact multiple of that of the design cylinder. The offset cylinders press the web against a separate impression cylinder, or against a second offset cylinder when two sides of the fabric are being printed at once, as is shown in Fig. 1. In this machine, a design in three colours is printed on each side of the web g' by means of rubber-covered offset cylinders d<1> - - d<6> which receive the designs from copper cylinders a<1>, b<1>, c<1>, and a<2>, b<2>, c<2>, having the designs engraved in intaglio and provided with ink rollers e<1> - - e<6> and scrapers f<1> - - f<6>. The designs in the cylinders a<1>, b<1>, c<1> are the reverse of those in the cylinders a<2>, b<2>, c<2>, and the designs printed are continuous. In a modification, the offset cylinders d<1>, d<3>, d' print in coaction with a large impression cylinder, and the web is then led to a second large impression cylinder with which offset cylinders such as d<2>, d<4>, d<6> coact, electrical or other drying means being used for the impressions. In another modification, Fig. 3, engraved plates which may be reproduced by three-colour processes, or by the aid of lithography, are secured to cylinders a<1>, b<1>, c<1>; a', b', c<2>, and the gaps between the plates filled in as described in Specification 117,888. These cylinders print on offset cylinders d<1> - - d<6>, two cylinders being required for each colour. The offset cylinders for each colour may receive a design of exactly half its circumference, so that the two offset cylinders of each colour print a complete continuous design between them, or these partial designs may overlap each other. In a further modification, especially adapted for printing table cloths, flags, &c., offset cylinders such as d', d<2>, d' may print designs in one or more colours with an unprinted interval between the designs. In some cases, the web is wound up after being printed on one side, and the other side of the web is printed in the same machine by changing the printing rollers and printing on the plain side of the wound web by a separate operation.