GB535197A - Improvements in or relating to means for printing and drying printed surfaces - Google Patents

Abstract

535,197. Printing-machines. GOSS PRINTING PRESS CO., Ltd. Feb. 26, 1940, No. 3567. Convention date, May 10, 1939. [Class 100 (ii)] Drying apparatus; inking apparatus. Printed products, particularly webs printed in fast multicolour rotary presses, printed with an ink comprising a non-volatile colour in a highly volatile solvent, are dried by subjecting them to a partial vacuum in a substantially sealed chamber arranged around a drum over which the web &c. is passed. As shown, a web w is printed in four colours by printing cylinders 2, 3, 4, 5 and impression cylinder 1, passes to a drying drum 20 and thence to a similar printing and drying apparatus for perfecting. The drying apparatus comprises a drum 20 provided with a casing 21 forming a chamber 22 which is connected to a suction pump 30. The casing has end walls 23 engaging, with interposed sealing strips, the ends of the drum 20, and walls 27 which leave just sufficient space for the passage of the web w. Non-radial baffles 37 may be provided adjacent the entry and exit passages of the web to impede entrance of air into the chamber. Mild heating elements, such as radiant or infra-red heaters 38 may be provided in the chamber to raise somewhat the vapour pressure of the ink solvent and to replace heat lost by the ink evaporation. The inking devices for the rollers 2, 3, 4, 5 may be enclosed in casings having removable walls to provide access to the parts, the casings being provided with cooling coils 43 connected to a refrigerator to reduce evaporation of the ink solvent in the fountains and on the inking apparatus.