SILVERLESS PHOTOGRAPHIC RECORDS, AND METHODS AND COMPOSITIONS FOR MAKING THEM

摘要

1294127 Photographic processes especially for producing continuous tone images W R GRACE & CO 10 Oct 1969 [11 Oct 1968 28 April 1969] 50005/69 Heading G2C A process for producing negative relief images comprising imagewise exposing through a transparent support, a composition on the support and comprising (a) a photo-sensitive material which cross-links on exposure and solidifies to a depth proportional to the intensity of exposure (b) a photo-sensitizer and (c) from 1-25% of a pigment or from 0À1 to 25% of a dye, by weight of the composition and uniformly distributed so that the solidified composition has a scale index and a gamma between 0À5 and 1À5 and removing unsolidified portions to leave a relief image. The material is preferably a polyese and a polythiol as in Specifications 1215591 and 1251232 and a composition containing such material and dye or pigment in the above amounts is disclosed in Specification 1294128. Preferably continuous tone images are produced by sandwiching the composition between two supports and exposing to a continuous tone transparency through the transparent support, removing the second support with the uncross-linked composition thereon and exposing this composition to produce positive and negative solidified images. Colour proofs may be produced by exposing three compositions containing yellow, magenta and cyan dyes respectively to the appropriate colourseparation negative, developing the composition and laminating the developed compositions to produce the proof. Half-tone and line images may also be produced by the process. Positive images are produced by using a white pigment and adhering the transparent support of the relief image to a black background. Similarly, compositions containing black pigments e.g carbon black may be adhered to white backgrounds after development. The relief images may be uniformly exposed to ensure complete curing.