Process for producing heat developable light-sensitive compositions and elements

Claim 1

In a process for producing an unexposed, coatable thermally developable light-sensitive composition of improved sensitivity which process comprises heating a composition containing an organic silver salt and a light-sensitive silver halide and after the completion of said heating adding a reducing agent, the improvement wherein a sulfur-containing compound is added to the organic silver salt and the light-sensitive silver halide and the sulfur-containing compound, organic silver salt and light-sensitive silver halide are heated at about 30° C. to about 70° C. for about 5 minutes to about 300 minutes, at which temperature said improved sensitivity is obtained, which sulfur-containing compound comprises at least one labile sulfur atom and forms silver sulfide upon reaction with the organic silver salt or the silver halide, wherein said sulfur-containing compound is represented by one of the following general formulae: M.sup.I S.sub.2 O.sub.3 or M.sup.II S.sub.2 O.sub.3 wherein MI I represents a monovalent cation and M II represents a divalent cation; R.sub.2 --CS--NR.sub.1 R.sub.3 wherein R 1 represents a hydrogen atom, an alkyl group, a carboxy- or aryl-substituted alkyl group, an alkenyl group, an aryl group, an alkyl-, carboxy- or carboxyalkyl substituted aryl group or an acyl group wherein said group or R 1 contains 12 or less carbon atoms; R 2 is a group selected from the class consisting of those represented by the following general formulae: R.sub.4 R.sub.5 N--, R.sub.6 R.sub.7 N--CS--NR.sub.8 --NR.sub.9 --, ##STR39## R.sub.12 R.sub.13 C═N.sub.14 -- wherein R 4 to R 14 are the same as defined for R 1 and n represents an integer of 1 to 3; and R 3 is the same as defined for R 1 ; ##STR40## wherein Z 1 represents the atoms necessary to form a 5- or 6- membered heterocyclic ring, which heterocyclic ring may fuse with an aromatic ring, and which heterocyclic ring can be substituted with a substituent having 24 or less carbon atoms selected from the group consisting of an alkyl group, an aryl-substituted alkyl group, a carboxy-substituted alkyl group, an alkylidene group, an alkyl-substituted alkylidene group, a carboxy-substituted alkylidene group, a carboxyalkyl-substituted alkylidene group, an aryl group, an alkyl-substituted aryl group, a carboxy-substituted aryl group, a carboxyalkyl-substituted aryl group, an arylidene group, an alkyl-substituted arylidene group, a carboxy-substituted arylidene group and a carboxyalkyl-substituted arylidene group, and R 15 represents a hydrogen atom, an alkyl group, a carboxy- or aryl-substituted alkyl group, an alkenyl group, an aryl group or an alkyl-, carboxy- or carboxyalkyl-substituted aryl group wherein said group for R 15 contains 12 or less carbon atoms; and ##STR41## wherein R 16 , R 17 , R 18 and R 19 each represents a member selected from the group consisting of a hydrogen atom, an alkyl group having 12 or less carbon atoms or an aryl- or carboxy-substituted alkyl group having 12 or less carbon atoms.