| 摘要 |
1,234,815. Forming conductivity images. ITEK CORP. July 10, 1968 [July 13, 1967 (3)], No.32800/68. Heading G2H. Latent conductivity images developable by means of the liquid redox systems described in Specification 1, 043, 250 into negatives images of the original are obtained by (i) imagewise or uniformly exposing a photo-conductive layer to bandgap light e.g. U. VI, (ii) allowing the layer to decay until it is substantially non-conductive and then (iii) respectively uniformly or imagewise exposing to light of a wavelength longer than said bandgap light e. g. green light. Latent images developable to positive images may be obtained if after step (iii) the layer is again decayed and then uniformly exposed as in step (iii). The images may also be developed with monomers polymerized in the latent image areas e. g. acrylamide/ methylene bisacrylamide to give relief images or liquid developers as described in Specification 935, 621. The photo-conductive layer may be dye sensitized, the dye being subsequently removed by alkaline sulphites or bisulphites. In the examples the photo-conductive layer is TiO 2 dispersed in polyvinyl alcohol or an acrylate binder. |
