GB893545A - Improvements in photographic dye imbibition processes - Google Patents

Abstract

893,545. Photographic dye-imbibition processes including multi-colour reproduction. KODAK Ltd. July 10, 1958 [July 10, 1957], No. 22181/58. Class 98(2). A silver halide image in an emulsion layer is colour developed to form an image of non- diffusing ionic compound or dye, this image is dyed up with a diffusing ionic dye of opposite charge, and the dyed up layer is placed while moist in contact with a receiving layer containing a mordant for the diffusing dye for image-transfer thereto. In a first form of the invention the coupler is in the developing solution and either coupler or developing agent is anionic or cationic, to form the non- diffusing dye, and the diffusing dye for application thereto is of opposite character. The silver halide image for this may result from direct exposure, bleaching of a silver image in a silver containing relief image as used in imbibition processes, or reversal treatment, and is normally a separation record. In a second form the coupler is in the emulsion and may have an acid group in a non-coupling position and develop to a soluble dye, leaving non-diffusing coupler in non-image areas. Repeated transfers may be made to a single receiving layer to form multicolour image. In Example 1, the first form, a positive film is exposed to a red-light colour-separation image, treated in a developer containing 4- amino - N - (10 carboxydecyl)-N-ethyl-3-methyl aniline and the anionic coupler 1-hydroxy-N- [2 - (#- sulphoethoxy) phenyl]-2-naphthamide, rinsed, fixed, washed, treated in a ferricyanidebromide bleach solution, rinsed, refixed, bathed in methylene blue dye solution, rinsed and placed in contact with a receiving blank having a gelatin coating containing the acid mordant 1 -hydroxy-4-chloro-N- { 4-[2-(2:4-ditert. - amylphenoxy) - 5 - (3 : 5-disodium-sulphobenzamido)-benzamido] - phenethyl} - 2 - naphthamide, which blank had been pre-conditioned with acetic acid, to transfer the dye image thereto. A series of cyan images may be so made by repeating the dyeing, rinsing and transferring steps. Magenta and yellow basic dye images prepared from the green and blue light colour separation images of the same subject are applied to the blank similarly. Examples 2, 3 also transfer methylene blue images, the first of these with use of different coupler and developing agent and the second including reversal procedure. Examples 4, 5 specify cationic dye images for use with acid dyes and a polyvinylaminoguanidine mordant as of Specification 850,281. Example 6 illustrates the second form of the invention with coupler in the emulsion layer and solutions and processing times therefor are fully described. Numerous couplers, colour developers, dyes and mordants are listed. Specifications 654,266 and 804,661 also are referred to.