Ciba-geigy Ag

Ilford Limited

Terence C Webb

William E Long

Rainer Kitzing

Graham Evans

John G Scott

Kenneth M McCombe

Stephen R Postle

Norman A Smith

Patrick D Thomas

Michael John Parker

David L Reeves

Samuel B Kingston

Malcolm D Tirel

Anthony Martin Lannon

Martin C Grossel

Monica H Gent

Marion R Palmer

Peter A Lovell

There is described a concentrated photographic silver halide developing solution which comprises from 50 to 150 g/liter of an ascorbic acid type compound of the general formula I: ##STR1## or alkali metal salts thereof, in which the group R represents a hydroxylated alkyl group, and at least one basic compound the anion of which is carbonate, sulphite or hydroxide of which the cation is an alkali metal, especially sodium or potassium, the total sodium to total potassium ion ratio in the concentrated developing solution being from about 50:50 to 0:100 (mole: mole). Preferably the concentrated solution is entirely aqueous but it may comprise a proportion of water-miscible organic solvents such as ethyl alcohol, or glycol solvents.

Concentrated photographic developing solution

Method of processing photographic silver halide material wherein an imagewise release of the development inhibitor 1-aryltetrazole-5-thiol is achieved during processing.

Processing of photographic silver halide materials

Salts of 1-phenyl-3-pyrazolidinones with organic sulphonic acids, which are useful photographic silver halide developing agents.

Photographic developing agents containing stable, soluble,

Compounds of the formula ##STR1## wherein L is a direct bond or consists of a chain of carbon atoms or of a divalent ring system, R.sub.1 to R.sub.4 are hydrogen or alkyl, R.sub.5 or R.sub.6 are hydrogen, alkyl or aryl, or R.sub.5 together with R.sub.6 complete a ring system, and R.sub.7 is hydrogen or a group of the formula ##STR2## wherein L, R.sub.5 and R.sub.6 are as defined. These compounds are useful developing agents for activation processing.

Protected developing agents

Process for the preparation of a photographic material comprising in at least one layer photographic useful compounds, e.g. color couplers or developers, which are occluded into solid polymer particles of 0.1 to 0.5 .mu.m in size.

Process for the preparation of photographic materials

Development inhibitor releasing compounds of the formula: ##STR1## are provided wherein R.sub.1 is hydrogen or a substituent which may contain a long chain ballasting group and n is 1 or 2, or R.sub.1 may form an annelated ring, R.sub.2 is hydrogen or alkyl having 1 to 4 carbon atoms, R.sub.3 is alkyl, aryl or aralkyl, Y is hydrogen, halogen, optionally substituted phenyl, --COOR.sub.4, --COR.sub.4, ##STR2## or --OR.sub.4 where R.sub.4 is alkyl or aryl or a group ##STR3## where Z represents the atoms necessary to complete an optionally substituted 5- or 6-membered heterocyclic ring which optionally may be benzannelated. The new DIR-compounds form colorless compounds when reacted with the oxidation products of the color developing agent. They have an extremely high reactivity with the oxidation products of the color developing agent so that only small quantities of the DIR-compounds are required to produce excellent intra-image and inter-image effects of excellent speed.

Substituted 1,2,4-triazoles as DIR compounds and their use in

A process for the production of a photographic image which comprises

Process for the production of photographic images and photographic

Development inhibitor releasing compounds of the formula ##STR1## are provided wherein R.sub.1 is hydrogen or a substituent which may contain a long chain ballasting group and n is 1 or 2, or R.sub.1 may form an annelated ring, R.sub.2 is hydrogen or alkyl having 1 to 4 carbon atoms, R.sub.3 is alkyl, aryl or aralkyl, Y is hydrogen, halogen, optionally substituted phenyl, --COOR.sub.4, --COR.sub.4, ##STR2## or --OR.sub.4 where R.sub.4 is alkyl or aryl or a group ##STR3## where Z represents the atoms necessary to complete an optionally substituted 5- or 6-membered heterocyclic ring which optionally may be benzannelated. The new DIR-compounds form colorless compounds when reacted with the oxidation products of the color developing agent. They have an extremely high reactivity with the oxidation products of the color developing agent so that only small quantities of the DIR-compounds are required to produce excellent intra-image and inter-image effects of excellent speed.

Development inhibitor releasing compounds and their use in photographic

Pyridone dyestuffs of the formula ##STR1## are provided wherein R.sub.1 is hydrogen or an optionally substituted alkyl, aralkyl, cycloalkyl, aryl or heterocyclic radical or an optionally substituted amino group,

Photographic elements containing amino-substituted hydroxy-pyridones

A light-sensitive photographic material is provided which comprises, coated on a photobase, at least one silver halide emulsion layer, said emulsion layer or a layer adjacent thereto containing a development inhibitor releasing compound of the formula ##STR1## wherein R.sub.1 is substituted phenyl which contains a ballasting alkyl group, R.sub.2 represents the atoms necessary to complete a five or six membered heterocyclic ring system which may be further substituted and R.sub.3 is an aryl or heterocyclic radical, any of which ring systems may be further substituted, the group --S--R.sub.3 being a development inhibiting group.

Light sensitive photographic material containing development inhibitor

Pyridone dyestuffs of the formula ##STR1## are provided wherein R.sub.1 is hydrogen or an optionally substituted alkyl, aralkyl, cycloalkyl, aryl or heterocyclic radical or an optionally substituted amino group, R.sub.2, R.sub.3, R.sub.4 each independently represent hydrogen, halogen, alkoxy, or optionally substituted alkyl or cycloalkyl, R.sub.5 and R.sub.6 each independently represent hydrogen or an optionally substituted alkyl, aralkyl, cycloalkyl, aryl or heterocyclic radical or R.sub.5 and R.sub.6, R.sub.3 and R.sub.5 and R.sub.4 and R.sub.6 form heterocyclic rings, Y is hydrogen or hydroxy, --CN, --COOR.sub.7, --CONR.sub.7 R.sub.8 or --COR.sub.7 or an optionally substituted alkyl, aralkyl, cycloalkyl, aryl or heterocyclic radical, and Z represents --CN, --COOR.sub.9, --CONR.sub.9 R.sub.10, --SO.sub.3 H, --SO.sub.3 .crclbar. or --COR.sub.9, where R.sub.7, R.sub.8, R.sub.9 and R.sub.10 each independently represent hydrogen or an optionally substituted alkyl, aralkyl, cycloalkyl, aryl or heterocyclic radical. The dyestuffs can be used e.g. as cyan image dyestuffs in photographic material, as diffusible dyes which may become mordanted in a receptor layer or as filter, antihalation or acutance dyes in photographic material.

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Wilmslow, United Kingdom

Terence C Webb