The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 31, 1983
Filed:
Feb. 13, 1981
Leslie F Mason, Brentwood, GB;
Rainer Kitzing, Ingatestone, GB;
Brian R Whitear, Brentwood, GB;
William E Long, Brentwood, GB;
Glenn P Wood, Brentwood, GB;
David L Reeves, Brentwood, GB;
Ciba-Geigy AG, Basel, CH;
Abstract
A photographic dye diffusion transfer process is provided which operates by imagwise release of a dye. The dye diffuses to a receiving layer and is mordanted there to give a dye image. The dyes are released from a compound of the formula D--E--F--BAL by reductive cleavage. D is a group which contains the residue of diffusible dye, BAL is a ballasting group which renders the compound containing it substantive to the layer in which it is present, D and E being joined by any type of chemical bond and E and F represent a single or double bond system which links D and BAL and which has a reduction potential above -200 mV measured against a standard hydrogen electrode at a pH of less than 3 and which bond can be reductively cleaved at a pH of less than 3 by a reducing agent which is able to act as a pH below 3.