GB1266112A - - Google Patents

Abstract

1,266,112. Multi-colour electro-photographic copier. FUJI PHOTO FILM CO. Ltd. July 20, 1970 [July 21, 1969], No.34995/70. Heading G2H. In a multi-colour electrostatic copier the original, sensitive sheet and projection lens remain in fixed positions while a plurality of processing units, one for each colour, and each comprising charging means, a colour filter and a developing means, are moved across the surface of the sensitive sheet, in succession, through the projection beam of the original. In Fig.3 three processing units are shown coupled together each comprising a corona charger 42 (in the first unit), an optical filter 43 of a particular colour, a developing roller 45 applying toner of the complementary colour, and a roller 44 immediately in front of the developer roller 45 for applying an insulative liquid to the sensitive sheet 35 to prevent 'fogging' during development. In addition the second and third units are provided with gaps, e.g. 47 in the second unit, through which unfiltered light from the projection beam may pass to sensitive sheet 35 to remove residual charge therefrom. Exposure alternatively may be from below the sensitive sheet, Fig. 4 (not shown), the copier of Fig. 5 the processing units 88 are coupled together beneath the sensitive material unwound from a roll 85 and held against a pressure plate 86, preferably by suction. Non-uniform sensitivity of the sensitive sheet 35 through the colour range used may be compensated for by adjusting the lengths of the colour filters in the direction of movement or by adjustment of the distance between the corona chargers and the sensitive sheet.