Agfa-gevaert Ag

Agfa Gevaert Nv

Bayer Aktiengesellschaft

Agta-gevaert Ag

Werner Krafft

Gunter Helling

Erich Wolff

Friedrich Jonas

Wulf Von Bonin

Willem Mues

Hartwig Andries

Gunther Matschke

Kurt Findeisen

Hans J Rosenkranz

Wolfgang Himmelmann

Leon L Vermeulen

Hans Langen

Gunter Renner

Immo Boie

Dirk Cyriel Quintens

Jan Gilleir

Bavo A Muys

Rudolf Meyer

Gabor Paal

Prem Lalvani

Louis Maria De Haes

Hans-Peter Vollmer

Hugo Karel Gevers

Gunther Arnold

Paul Desire Van Pee

Stephan Jeanne Bongaerts

Kurt-Rainer Stahlke

Gunter Matschke

Guunther Matschke

Gerd Krauss

A method is provided for applying a magnetic layer onto a polymeric sheet or web material comprising the steps of (i) simultaneously coextruding a non magnetic 'dummy' layer and a magnetic layer onto said polymeric sheet or web material, said non magnetic 'dummy' layer being closest to the support (ii) drying the coextruded layers characterised in that the sum of the wet coating thickness of said 'dummy' layer (Th.sub.dum) and of the wet coating thickness of said magnetic layer (Th.sub.mag) fulfils the equation 25 .mu.m.ltoreq.Th.sub.dum +Th.sub.mag .ltoreq.100 .mu.m and that the ratio of (Th.sub.mag) to (Th.sub.dum) fulfils the equation 0.01.ltoreq.Th.sub.mag /Th.sub.dum .ltoreq.1.

Method of applying a transparent magnetic layer to a web or sheet

A photographic material comprising a transparent film support having on one side at least one light-sensitive layer and on the other side a transparent magnetic layer and an antistatic layer of a polythiophene arranged above or below said transparent magnetic layer shows transparency and good mechanical and antistatic properties.

Photographic material

Antistatically treated plastic formed articles, e.g. photographic film supports, that contain at least two layers on the surface to be antistatically treated, wherein a layer nearer to the plastic surface contains a preparation of a polythiophene that is built up from structural units of the formula ##STR1## wherein R.sub.1 and R.sub.2 independently of each other stand for hydrogen or a C.sub.1 -C.sub.4 -alkyl group or together form an optionally substituted C.sub.1 -C.sub.4 -alkylene group, preferably a methylene group optionally substituted by alkyl groups, a 1,2-ethylene group optionally substituted by C.sub.1 -C.sub.12 -alkyl or phenyl groups, a 1,3-propylene group or a 1,2-cyclohexylene group, and a polyanion, a farther layer contains a film-forming polymer and at least one of the two layers contains an alkoxysilane, are characterized, apart from excellent antistatic properties, by very good layer adhesion.

Antistatic plastic articles

The invention relates to dispersions of polythiophenes made up of structural units corresponding to the following formula ##STR1## in which R.sub.1 and R.sub.2 independently of one another represent hydrogen or a C.sub.1-4 alkyl group or, together, form an optionally substituted C.sub.1-4 alkylene group,

Polythiophene dispersions, their production and their use

A photographic recording material comprising a support, at least one photosensitive, gelatine-containing silver halide emulsion layer on one side of the support and a gelatine-containing NC layer on the other side of the support, in which the NC layer contains a certain hydrophilic polymer, is distinguished by the fact that there is relatively little E.sub.a curl during drying whereas sufficient E.sub.i curl is present after drying, so that the material is not damaged during processing.

Photographic material comprising an NC layer

A photographic recording material containing at least one pyrazolone in at least one non-photosensitive layer I, a compound Sc, which reacts with the oxidation product of a p-phenylene diamine developer to form substantially colorless products and which is contained in a non-photosensitive layer which is not separated from the layer I by a photosensitive silver halide emulsion layer, shows improved protection against formaldehyde.

Photosensitive photographic silver halide recording material

The invention relates to a process for the production of colored images by the dye diffusion transfer principle, in which a color photographic recording material containing negative silver halide emulsions and reducible color-providing compounds is developed with an alkaline developer preparation containing a combination of at least one compound from each of at least two of the groups of compounds (A, B, C) defined below as development accelerators. With combinations of this type, equal or higher maximum color densities are obtained for a smaller overall quantity of development accelerator.

Dye diffusion transfer process with development accelerators

A color photographic material for the dye diffusion transfer process contains a temporary barrier layer that is applied from organic solution and consists of a mixture of

Photographic material containing a temporary barrier layer applied from

A photographic film unit for the production of colored transfer images contains an integral neutralization system consisting of an acid polymer layer and a retarding layer. The acid polymer layer consists of a copolymer of 5 to 50 % by weight of polymerized carboxyalkyl (meth)acrylate units together with other acid monomers and optionally nonacid monomers. A preferred carboxyalkyl (meth)acrylate is the dimeric acrylic acid. The acid polymer has high acid number and low glass transition temperature.

Photographic film unit for the production of colored transfer images

A restraining layer capable of retarding the diffusion of hydroxyl groups is of particular use in a neutralization system for the dye diffusion transfer process. The restraining layer of the invention comprises a film-forming linear polymer consisting of alternating hydrophilic and hydrophobic segments joined to one another by carbonate, urethane and/or ester groups. The neutralization system provides retarded reduction of pH in the photographic material.

Restraining layer for retarding the diffusion of hydroxyl ions in the

The neutralization layer (acid polymer layer) in a photographic film unit for the production of colored transfer images contains a crosslinked acrylic or methacrylic acid copolymer having at least 30 mol % of copolymerized acrylic acid or methacrylic acid and the crosslinking has been brought about by copolymerizing said acid monomers or the corresponding esters together with a crosslinking agent having at least two copolymerizable carbon-carbon double bands.

Photographic film unit with crosslinked neutralization layer

Copolymers of methylacrylate/alkyl acrylate or methyl methacrylate/alkyl methacrylate are used as a binder for UV-sensitive recording materials, preferably recording materials which contain substances which are capable of discoloration.

Polymer binder

A neutralization system for the dye diffusion transfer process comprises an acid polymer layer containing a polymer with free acid groups and a retarding layer. The retarding layer contains a hydratable polymer which in its non-hydrated state is a barrier for hydroxyl ions and in its hydrated state provides no resistance for diffusing hydroxyl ions. The retarding layer is arranged between a laminate consisting of a light-sensitive film unit comprising at least a light-sensitive silver halide emulsion layer and a non-diffusible dye giving compound associated with the light-sensitive silver halide emulsion layer. The retarding layer allows a first high pH value to be maintained during a first time interval which is sufficient and necessary for producing the desired image density in the image receiving layer and thereafter a second low pH value to be adjusted within a second time interval which is less than half as long as the first. Suitable polymers for the retarding layer are homo-, co- and graftpolymers of 1,2-dimethoxyethylene.

Diffusion retarding layers comprising polymers of dimethoxyethylene

In a photographic monosheet material for the dye diffusion transfer process a temporary bond is adjusted between a first layer and a second layer by placing between said layers another layer of a graft polymer which is obtained by grafting a monomer containing double bonds capable of radical polymerization onto a hydrophilic linear basis polymer. The two layers are firmly bonded to each other but are easily separated, when the processing liquid is forced between them.

Dye diffusion transfer material with graft polymer binding layer

A storage medium for optical data recording comprises a dye-forming combination which on exposure to light within a first range of wavelengths reacts irreversibly to form a dye, but is substantially insensitive to light within a second range of wavelengths which is capable of energizing the dye to produce luminescence. The dye-forming combination consists of a heterocyclic compound of the formula I and of a cyclic dihalodicarbonyl compound of the formula II ##STR1## The symbols are defined in the specification. An example of formula I is benzofuran and an example of formula II is dibromomaleic anhydride.

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Leverkusen, Germany

Werner Krafft