Process for the production of a laminated article
AssigneeAgfa-Gevaert
InventorsLeon L. Vermeulen, Robert S. Pauwels, Piet Kok, Jean-Marie O. Dewanckele
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Abstract
Process for the production of a laminated article including a sheet support bearing a silver image produced by the silver complex diffusion transfer process in a layer containing developement nuclei, wherein such supported image is heat-laminated with a protective thermoplastic resin layer of sheet that covers it. The heat-lamination of the nuclei-containing layer with the silver image therein takes place in the presence of at least one of certain heterocyclic black-toning agents which are effective to prevent degradation of the neutral black coloration and density loss of the silver image as a result of heat-lamination.
Claims10
A process for the production of a laminated article including a sheet support bearing a silver image produced by the silver complex diffusion transfer process in a layer containing development nuclei, wherein said image is heat laminated with a protective thermoplastic resin layer or sheet that covers said supported silver image, and wherein said layer containing development nuclei contains said silver image during the heat-lamination procedure in the presence of one or more heterocyclic thione compounds or tautomeric thiol representatives thereof acting as black-toning agents and corresponding to one of the following general or structural formulae (I) to (V):
- ##STR17## wherein R.sup.1 represents a C1-C4 alkyl group, an allyl group or a phenyl group;
- ##STR18## wherein R.sup.2 represents a C1-C4 alkyl group or an allyl group;
- ##STR19## wherein R.sup.3 represents a C1-C4 alkyl group or a phenyl group.
Dependencies are inferred from the claim text.