| 摘要 |
Particles of powder, containing a dye maintained according to an image in particulate form on or in a substrate, are contacted with the vapour of a solvent for the dye which also swells the surface of the substrate by adsorption by the dye. This is a novel step in xerographic image formation, being preceded by exposing to actinic radiation until brightened a substrate (I) bearing a photosensitive organic layer, applying powdered particles (II) comprising a solid support (III) and dye; immersing at a temp. less than all the materials m.pt. to give an image in which the particles vary in density according to exposure; excess particles are removed to develop the image, the final step being described previously. (I) may be paper bearing a layer of hardened gelatine, PVA or polyvinylpyrrolidone. (III) may be PVA, a butadiene-vinyl toluene copolymer, or rice or maize starch. |
