Minnesota Mining and Manufacturing Company

Imation Corporation

Carlo Marchesano

Filippo Faranda

Franco Buriano

Elda Moizo

Andrew W Mott

Dian E Stevenson

Jonathan P Kitchin

Marco Bucci

Marco Loiacono

Dino Ferrari

Enrico Furlanetto

Carlo Illuminati

A photographic fixer compositions comprising a silver halide solvent, an aluminum salt hardening agent, a buffering agent and ammonium ions in amount of at least 0.20 mol/l, wherein said fixer composition also contains at least an aminopolycarboxylic acid sequestering agent of formula (I-a) or (I-b) or a water-soluble salt thereof and d) at least a polyphosphonic acid sequestering agent of formula (II-a), (II-b), (II-c), (II-d') or (II-d'): ##STR1## wherein the substituents are defined in the specification. The present invention also provides a method of processing an exposed photographic silver halide element comprising the steps of developing by means of a developer comprising a silver halide developing agent and treating the developed element with a fixer composition, wherein the fixer composition is one described above.

Photographic fixer compositions and method for processing a photographic

The present invention provides a fixer composition and a method of processing an exposed photographic silver halide element comprising the steps of developing by means of a developer comprising a silver halide developing agent and treating the developed element with a fixer composition, wherein the fixer composition comprises a silver halide solvent, a sulfite ion source, an aluminum salt hardening agent, a buffering agent, a sequestering agent and an .alpha.-ketocarboxylic acid compound in an amount of more than 2 grams per liter corresponding to the formula:

Photographic fixer composition and method

The present invention relates to a black-and-white aqueous alkaline photographic developer composition, free of dihydroxybenzene developing agent, comprising a reductic acid developing agent and an auxiliary superadditive developing agent, wherein the reductic acid developing agent is represented by the formula (I): ##STR1## wherein, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each are selected from the group consisting of hydrogen and group CH.sub.2 R.sub.5, wherein R.sub.5 is hydrogen or a monovalent group, e.g. amino, cyano, halogen, hydroxyl, carboxyl, sulfonyl, alkyl, cycloalkyl, aryl. A process for forming a black-and-white photographic silver image comprising developing a silver halide photographic element with said black-and-white aqueous alkaline photographic developer composition is also described.

Photographic silver halide developer composition and process for forming

A process for forming a black-and-white high contrast negative photographic silver image by development of a silver halide photographic element with an aqueous alkaline photographic developer composition comprising a dihydroxybenzene developing agent, an auxiliary superadditive developing agent, an antifogging agent, an antioxidant compound, a combination of buffering agents and a sequestering agent, characterized by the fact that: a) the auxiliary developing agent is an aminophenol compound, b) the combination of buffering agents comprises at least a first buffering agent represented by carbonate compounds and at least a second buffering agent represented by phosphate compounds, the total amount of said first buffering agent and said second buffering agent being at least 35 grams per liter, band c) the pH of said aqueous alkaline photographic developer composition is in the range 9.0 to 11.0.

Photographic silver halide developer compositions and process for

The present invention relates to an alkaline aqueous black-and-white photographic developer composition comprising:

Alkaline black-and-white developer for silver halide photographic

This invention relates to a method of processing an image-wise exposed silver halide photographic material wherein said method comprises the following steps:

Method of processing a silver halide radiographic material

A ready-to-use photographic color developing composition for the development of high bromide silver halide photographic element, said composition being substantially free of bromides, hydroxylamines and benzyl alcohol and comprising a color developing agent, a buffering agent, a complexing agent, an antifogging agent, a contrast promoting agent, an antioxidant agent and a polyol compound. A rapid access processing method of a high bromide silver halide photographic color element, said method comprising the steps of:

Photographic color developing composition and method for processing a

A concentrated alkaline photographic developer composition, packaged in a single part to be diluted with water to form a ready to use developing solution for silver halide photographic materials, which comprises dihydroxybenzene developing agents, inorganic alkali agnets, inorganic antioxidant agents, sequestering agents and antifoggants, wherein said inorganic antioxidant agents comprise Na.sub.2 SO.sub.3 (sodium sulfite) and K.sub.2 SO.sub.3 (potassium sulfite) in a molecular ratio of 1:1 to 1:3 in an amount of from 1.6 to 4 moles per liter, the molecular ratio between said inorganic antioxidant agents and the developing agents is from 1.50 and 4.00, and said concentrated developer composition has a specific gravity higher than 1.300 at 20.degree. C., and a method of making a concentrated alkaline photographic developer composition, packaged in a single part to be diluted with water to form a ready to use developing solution for silver halide photographic materials, which comprises dihydroxybenzene developing agents, inorganic alkali agents, inorganic antioxidant agents, sequestering agents and antifoggants, characterized in that comprises the following steps:

Concentrated photographic developer composition and method of making it

The addition to an aqueous alkaline developer composition for silver halide photographic materials of a dialkylaminomethane diphosphonic acid compound sequestering agent increases the resistance of the developer composition against aerial oxidation and inhibits calcareous deposit formation.

Developer compositions for silver halide photographic materials

High contrast negative images are obtained by developing a silver halide photographic element, in the presence of a hydrazine compound, with an alkali aqueous developing solution which contains a combination of developing agent comprising hydroquinone or substituted hydroquinone and a superadditive developing agent and an antioxidant, wherein the developing solution has a pH lower than about 12 and wherein the silver halide photographic element comprises an emulsion layer including surface latent image negative type silver halide grains in reactive association with a contrast promoting agent, preferably a diarylcarbinol compound, more preferably a diarylmethanol compound in a quantity useful to increase contrast.

Process for the formation of high contrast negative images and silver

An aqueous alkaline photographic silver halide developer composition comprising a dihydroxy benzene developing agent, an auxiliary superadditive developing agent, an antifogging agent, an antioxidant and a buffering agent, characterized by the fact that the composition further comprises a stabilizing amount of an .alpha.-ketocarboxylic acid. The developer composition has a better resistance against air oxidation and can be left in continuous transport automatic processors for several days without undergoing any substantial decrease of its developing properties. The developer composition is particularly useful in a process for the formation of a high contrast silver image by developing silver halide photographic elements including at least a negative acting surface latent image type silver halide emulsion in the presence of a hydrazine compound, preferably in the additional presence of an effective amount of a contrast promoting agent.

A process is disclosed for forming a high-contrast photographic image by developing a silver halide photographic element, including at least a silver halide emulsion layer, with an aqueous alkaline developing solution containing a dihydroxybenzene developing agent, a superadditive developing agent and an antioxidant at a pH of less than 12 in the presence of a hydrazine compound, an organic antifogging and contrast promoting agent selected within the class including a benzotriazole compound and a benzimidazole compound and a non polymeric hydroxymethylidyne group containing compound of formula: ##STR1## wherein R.sub.1 and R.sub.2 each independently represent a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, or R.sub.1 and R.sub.2 together complete a non aromatic cyclic group.

Process for high contrast development of photographic elements

Color developer composition packaged in two or more concentrated parts, which on mixing with water give a ready-for-use silver halide developer solution, one part thereof comprising an aqueous concentrated solution containing a N-hydroxyalkylsubstituted p-phenylene diamine salt developing agent and a sulfite compound, said aqueous concentrated solution having a pH from 6 to 8. In particular, said N-hydroxyalkyl-substituted p-phenylene diamine developing agent is a 4-amino-3-methyl-N-ethyl-N-(.beta.-hydroxyethyl)-aniline and the molar ratio of the sulfite compound to the developing agent is higher than 1.5:1.

Photographic color developer composition packaged in two or more

Developer for use in color photography confectioned in a plurality of concentrated compositions in which one first concentrated composition is a liquid composition substantially free of water including the p-phenylenediamine compound, and possibly other components of the developer such as antioxidants, dissolved in an organic solvent.

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Savona, Italy

Carlo Marchesano