(19)
(11) EP 0 055 858 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
16.03.1983 Bulletin 1983/11

(43) Date of publication A2:
14.07.1982 Bulletin 1982/28

(21) Application number: 81110833

(22) Date of filing: 29.12.1981
(84) Designated Contracting States:
BE DE FR GB NL

(30) Priority: 05.01.1981 US 222502
05.01.1981 US 222543
05.01.1981 US 222542
05.01.1981 US 222504

(71) Applicant: POLAROID CORPORATION
 ()

(72) Inventors:
  • Mehta, Avinash C.
     ()
  • Nawn, George H.
     ()
  • Taylor, Lloyd D.
     ()
  • Bartels-Keith, James R.
     ()
  • Borror, Alan L.
     ()

   


(54) Photographic products, diffusion transfer photographic process, and compounds used therefor


(57) There is disclosed a diffusion transfer photographic system wherein development of an exposed photosensitive element with an aqueous alkaline processing composition is effected in the presence of a compound represented by the formula

wherein X represents the nonmetallic atoms necessary to form a nucleus which completes a 5- or 6-membered heterocyclic moiety on said structure including substituted rings and fused rings; R is H, an alkali metal or a group which is cleavable in a photographic aqueous alkaline processing composition; and R, is either a group which has a pKa of from about 7 to about 14 which is ionizable to an anion whereby the silver salt of the mercaptan (resulting from cleavage or ionization of -SR) is rendered more soluble in the pH range within which R1 is ionized to an anion than it is below that pH range, or a precursor of such a group.






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