GB1020011A - Treatment of electrophotographic prints - Google Patents

Abstract

1,020,011. Electrophotography. EASTMAN KODAK CO. Oct. 16, 1962 [Oct.18, 1961], No. 39209/62. Heading G2H. To improve the contrast in an electrophotographic print including as the image-bearing layer a photoconductive material dispersed in a hydrophobic insulating polymeric binder and sensitized with a coloured dye, the dye-bearing layer is bathed or swabbed with one or more organic solvents, at least one being a solvent for the binder, for a time sufficient to discharge the colour of the dye from the layer but insufficient to remove the binder, and thereafter drying the layer. Reference is made to rendering the dye colourless, desorbing the dye, or to a combination of these treatments, but as described the treatment always effects desorbtions optionally with decolorization as by including in the solvent or solvent mixture an organic acid or a compound such as 1: 3-dichloro- 5 : 5-dimethylhydantoin. The materials employed comprise conductive supports bearing ZnO-inresin layers sensitized with one of more of triphenylmethane or merocyanine dyes. Auramine B or Rhodamine B, and prints are made either by powder developing an electrostatic latent image or by electrolytically developing a latent conductivity image to provide a deposit comprising silver and a mixed manganese-iron hydroxide or hydrated oxide as in Specification 1, 006, 114