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:
Dec. 23, 1986
Filed:
Apr. 29, 1985
Myron S Simon, West Newton, MA (US);
David P Waller, Lexington, MA (US);
Polaroid Corporation, Cambridge, MA (US);
Abstract
Photographic products and processes for the imagewise generation of a dye from a color shifted dye precursor of a preformed image dye, said precursor having at least one ##STR1## group, wherein R is hydrogen, alkyl, provided that the .alpha.-carbon does not have a hydrogen atom attached thereto, aryl such as phenyl or substituted phenyl, e.g. p-nitrophenyl, or heterocyclic such as pyridine; R.sub.1 -R.sub.6 are hydrogen, alkyl, preferably having from 1 to 6 carbon atoms, or aryl; n is 0 or 1; and T is a moiety containing a thiazolidin-2-yl group which upon silver-assisted cleavage of said thiazolidin-2-yl group results in the formation of a ##STR2## group, which may be protonated under the reaction conditions, followed by cleavage of said ##STR3## which cleavage is anchimerically assisted or accelerated by said ##STR4## to provide after protonation, an ##STR5## group in a dye chromophore. In a preferred embodiment the precursor is a substantially colorless compound.