Agfa Gevaert Nv

Agfa-gevaert

Eddy A Michiels

Frank P Michiels

Piet Kok

Johan August Loccufier

Geert H Defieuw

Ludo Van Rompuy

Luc H Leenders

Luc J Vanmaele

Serge M Tavernier

Gunter Helling

Frank Louwet

Jean-Marie O Dewanckele

Daniel M Timmerman

Yvan K Gilliams

Robert F Janssens

Lode Deprez

Hubert Vandenabeele

Kathy Elst

Marc Van Den Zegel

Daniel A Claeys

Rafael P Samijn

Yvan Hoogmartens

Andre Verhecken

Antonius A Rutges

Robert Cyriel Van Haute

Ivan Steels

Dmitry A Topchiev

Gennady G Kardash

A thermographic recording material, thermally developable under substantially water-free conditions, comprising a support and a thermosensitive element, the thermosensitive element being provided with a protective layer and the thermosensitive element containing a substantially light-insensitive silver salt of an organic carboxylic acid, a reducing agent therefor in thermal working relationship therewith and a binder, wherein the protective layer contains at least one proteinaceous binder and non-opacifying inorganic particles with a weight averaged diameter of less than,&mgr;m in a concentration of between 5 and 70% by weight with respect to the weight of the protective layer.

Substantially thermographic recording materials with improved stability

A light-sensitive silver halide photographic material has been provided comprising a support and on one or both sides thereof at least one light-sensitive silver halide emulsion layer, a gelatinous protective antistress layer and, adjacent thereto as an outermost layer, a gelatinous afterlayer characterized in that said afterlayer comprises at least one polymer latex, being a polybutylacrylate, a polybutylmethacrylate latex or a polyurethane latex, or a copolymer latex being a copolymer poly(butyl methacrylate) polyacrylamide N-substituted sulfo-isobutyl salt, in a ratio amount by weight of (co)polymer latex to gelatin from 0.2:1 up to 5:1 and a total amount of (co)polymer latex and gelatin of at least 0.10 g/m,.

Light-sensitive silver halide material providing improved surface characteristics after processing

A method has been described of preparing a photosensitive emulsion comprising tabular silver halide grains rich in silver bromide, having {100} major faces and an aspect ratio more than 1.5, wherein at least 50% of the projected area of all grains is provided by said {100} tabular grains, said method comprising the step of running in a reaction vessel an aqueous silver salt solution and an aqueous alkali halide solution rich in alkali bromide, characterized in that before starting running said reaction vessel comprises in an aqueous solution of gelatin an amount of amino-modified polyvinyl alcohol as an aqueous soluble polymer.

Method of preparing (100) tabular grains rich in silver bromide

A process for producing a thermographic recording material including on one side of a support, called the heat-sensitive side, a thermosensitive element, the outermost layer on the heat-sensitive side containing a cured polymer or cured polymer composition and silica, comprising the steps of: providing the heat-sensitive side of the support with an outermost layer by coating with a composition produced by mixing ingredients including colloidal silica, a curable polymer and a curing agent therefor; and drying and curing the outermost layer, wherein any acidic groups present in the colloidal silica upon acidification are substantially neutralized with ammonium ions, the curable polymer is a hydrophilic polymer having active hydrogen atoms and the curing agent is selected from the group consisting of polyisocyanates, aldehydes, titanates, zirconates, sulfone, boric acid and hydrolyzed tetraalkyl orthosilicate; and a method of recording an image therewith.

Outermost layers for use in thermographic recording materials

A modified gelatin is disclosed wherein part of the free carboxyl groups is replaced by modifiers having more acid end-standing groups chosen from --SO.sub.3 M, --OSO.sub.3 M, --SSO.sub.3 M, ---OPO(OH).sub.2, --OPO(OH)(OR.sup.2), --PO(OH).sub.2, --PO(OH)(OR.sup.2). In a preferred embodiment such a modified gelatin is incorporated in a DTR photographic material which after processing can serve as a lithographic printing plate. Thanks to the more hydrophilic character of the modified gelatin the differentiation between printing and non-printing areas is improved and toning at printing start-up is reduced.

Type of modified gelatin and its use in a DTR material

The present invention provides an imaging element comprising on the same side of a support in the order given a base layer, a light sensitive layer containing a silver halide emulsion and a surface layer comprising physical development nuclei characterized in that said base layer and/or said light-sensitive layer comprises gelatin being hardened with a divinylsulfonyl hardener such that the time needed to completely brake down said base layer, light sensitive layer and surface layer using an aqueous solution of 0.14% by weight of NaOCl at 25.degree. C. is between 1000s and 1600s. A lithographic printing plate can be obtained with such imaging element according to the silver salt diffusion transfer process and exhibits an improved printing endurance.

Imaging element for making a lithographic printing plate according to

A modified gelatin is disclosed wherein part of the free carboxyl groups is replaced by modifiers having more acid end-standing groups chosen from --SO.sub.3 M, --OSO.sub.3 M, --SSO.sub.3 M, --OPO(OH).sub.2, --OPO(OH)(OR.sup.2), --PO(OH).sub.2, --PO(OH)(OR.sup.2). In a preferred embodiment such a modified gelatin is incorporated in a DTR photographic material which after processing can serve as a lithographic printing plate. Thanks to the more hydrophilic character of the modified gelatin the differentiation between printing and non-printing areas is improved and toning at printing start-up is reduced.

New types of modified gelatins are disclosed, modified at part of the free carboxyl groups of the polypeptide chain, by the introduction of a new end-standing amino, sulphinic acid or thiol group. The modified gelatins show an enhanced reactivity towards vinylsulphonyl hardeners. The invention further includes hardened modified gelatin types and hydrophilic elements containing them. In particular, a differentially hardened multilayer element, preferably a photographic element, is disclosed.

Modified gelatin types and hydrophilic elements containing them

A process is disclosed for the purification of waste water containing a silver compound, comprising the steps of (1) adding to said waste water a salt of a poly(guanidine) or poly(biguanidine) polymer (2) adding a flocculant, and (3) filtrating the formed flocculate. The invention is particularly suitable for the removal of silver from the effluent of a photographic processor, and more specifically the effluent of a processor of wash-off materials, said effluent also containing gelatin. A most preferred poly(guanidine) compound is poly(hexamethyleneguanidine) hydrochloride.

Method for the purification of waste water containing silver

The present invention relates to a xeroprinting process, in particular a xeroprinting process comprising the following steps:

Xeroprinting process using reversal development process

The present invention provides a dye diffusion transfer imaging process comprising transferring image-wise by diffusion an acid dye to an image-receiving layer incorporating a non-polymeric phosphonium mordanting agent and a copolymer latex comprising free weak acid groups as a stabilizer for the mordanting agent, wherein the image-wise transfer of said acid dye is performed in the presence of a heterocyclic compound corresponding to one of the following general formulae I, II, and III: ##STR1## wherein: Y represents the non-metallic atoms needed to complete a saturated or unsaturated 5- or 6-membered heterocyclic nucleus, which may carry a fused-on aromatic ring system, and M represents hydrogen, an alkali metal atom, a quaternary ammonium group, or a negative charge forming an inner salt with a quaternized nitrogen atom of the heterocyclic compound. The invention also provides an image receptor element for dye diffusion transfer imaging processes comprising a support and such image-receiving layer.

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Kontich, Belgium

Eddy A Michiels