GB1246270A - Printing - Google Patents

Abstract

1,246,270. Printing processes. STANDARD TELEPHONES & CABLES Ltd. 13 Dec., 1968 [20 Dec., 1967], No. 57879/67. Heading B6C. [Also in Division G5] Display and printing apparatus comprises a non-magnetic metal or plastics band 1 provided with a film (6) of thermoplastics material impregnated with magnetic powder particles (5, Fig. 2) in which apparatus the film (6) is softened by the application of heat either before, during or after the application of magnetic field patterns, and wherein the deformations which are formed in the film by the local attraction of the magnetic powder particles by the magnetic field, are retained in the film by cooling. The apparatus may be used to display and print alphanumerical matter, pictorial matter such as graphs, diagrams or maps, or facsimile which are reproductions of any type of original. In Fig. 1, the band 1 after passing a heater 4, magnetic recording head assembly 3 and cooling unit 9, is then passed to a display position where the visible image can be viewed in a mirror 11. Thereafter, the band passes through a printing station which includes a grinding wheel unit 17 for removing the top portions (19) of the deformation (8, Fig. 4), an inking unit 15, 16 for transferring ink to the flattened tops of the deformations, and pressure rollers 2 and 18 which transfer the image to a web 19 fed from a supply-roll 171. The band finally passes through an erasure station which includes a heater 23, demagnetizing head 24, a cooling unit 25 and a washing unit 27, 26. The erasure station is selectively operated. (Fig. 5) illustrates an alternative embodiment having a non-magnetic metal drum (la) instead of a band 1. As a further alternative, the film 6 may be situated on the other side of a band 1 of plastics material so that indentations are produced in the surface of the film 6 instead of raised portions.