Process for hardening photographic gelatin with vinyl sulfones containing sulfonyl ethyl sulfate groups

Claim 2

A process of hardening a photographic material consisting of a layer support and at least one gelatin-containing layer applied to this support, comprising incorporating in the casting composition of a gelatin-containing layer applied to the layer support or in a gelatin-containing layer applied to the layer support a cross-linking agent which is reactive with the amino groups of the gelatin wherein the cross-linking agent is a compound containing at least one sulfone group and at least one vinyl sulfonyl ethylsulfate group as a water-solubilizing group in the form of their salts and wherein the cross-linking activity of the compound with the gelatin is carried out after drying said gelatin-containing layer and at a Ph value of from 6 to 7.

Claim 3

A process according to claim 1, characterised in that the cross-linking agent used is a compound corresponding to the following general formula: (--Y--SO.sub.2 --CH.sub.2 --CH.sub.2 --OSO.sub.3.sup.⊖ Me.sup.⊕).sub.n .sup.Z (--Y--SO.sub.2 --CH═CH.sub.2).sub.m wherein Z=a divalent to n+m valent aliphatic, saturated or olefinically unsaturated straight chain or branched chain, optionally substituted hydrocarbon group having 1-9 carbon atoms which may contain oxy groups, or a divalent to n+m valent, optionally substituted, aromatic or partially or completely hydrogenated carbocyclic or heterocyclic group, or the group ##STR12## Y=a single bond, a branched chain or straight chain alkylene group having 1 to 4 carbon atoms in which the chain may be substituted and interrupted by oxy, carbonyl and imino groups, n=an integer of from 1 to 3, m=an integer of from 1 to 3, and Me.sup.⊕ =an alkali metal ion.

Claim 4

A process according to claims 1 or 2, characterised in that the casting composition of a gelatin-containing layer to be applied contains the cross-linking agent.

Claim 5

A process as claimed in claims 1 or 2 characterized in that the photographic material is a multilayer material and wherein said cross-linking agent is incorporated into at least one of the casting solutions of the gelatin containing layers of the multilayer material and in such a quantity that the concentration of said agent in said multilayer material is of from 0.5 to 5 percent based on gelatin.