US3615511A - Surface developer with heterocyclic mercaptan for use on internal image emulsion - Google Patents

Surface developer with heterocyclic mercaptan for use on internal image emulsion Download PDF

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Publication number
US3615511A
US3615511A US731275A US3615511DA US3615511A US 3615511 A US3615511 A US 3615511A US 731275 A US731275 A US 731275A US 3615511D A US3615511D A US 3615511DA US 3615511 A US3615511 A US 3615511A
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silver
complexing agent
process according
mercaptoimidazole
groups
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Expired - Lifetime
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US731275A
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English (en)
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Roger M Cole
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Eastman Kodak Co
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Eastman Kodak Co
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/49—Print-out and photodevelopable emulsions
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
    • G03C5/29—Development processes or agents therefor
    • G03C5/30—Developers
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
    • G03C5/29—Development processes or agents therefor
    • G03C5/305—Additives other than developers

Definitions

  • the developing or stabilizing compositions of this invention contain low concentrations of a silver complexing agent.
  • photographic compositions are stabilized or developed with a process comprising a bleach bath followed by a surface type developer.
  • direct-print materials containing either photodeveloped images or nonphotodeveloped latent images can be processed to provide permanent image records.
  • This invention relates to processes and compositions for developing or stabilizing image records in photographic materials.
  • this invention relates to novel processes for developing or stabilizing image records in directprint, photographic materials.
  • this invention relates to novel processes comprising bleaching and then developing or stabilizing image records in direct-print -material.
  • this invention relates to a means by which both latent images and photodeveloped images can be made into stable, permanent image records.
  • direct-print compositions which have been imagewise exposed are processed in a surface developer containing selective silver complexing agent, fixed and washed.
  • direct-print records which have been imagewise exposed are photodeveloped to a discernible image and then processed in a surface developer containing a selective silver complexing agent, fixed and washed.
  • direct-print compositions which have been imagewise exposed are bleached and then processed in a surface developer containing a selective silver complexing agent, fixed and washed.
  • direct-print compositions which have been imagewise exposed are photodeveloped, bleached, processed in a surface developer containing a selective silver complexing agent, fixed and washed.
  • the selective silver complexing agents of this invention contain two characteristic groups which provide the unique properties in the surface developers.
  • the silver complexing agents contain at least one group which is capable of forming a normal covalent bond with silver.
  • Typical complexing agents contain groups capable of forming the covalent bonds such as -S-Ag, N-Ag and the like.
  • the preferred complexing agents contain imide groups mercaptan groups (SI-l) and the like or tautomers thereof.
  • the complexing agents also contain at least one secondary bonding group which does not generally form a covalent bond with silver under the conditions generally encountered in photographic emulsions and photographic developing solutions. Bonds of this type are sometimes referred to as 1r bonds in the atomic configuration of the ion complex formation.
  • Typical groups in the silver complexing agents of this invention which can be classified as'secondary bonding groups are or carbon-carbon double bond groupsythese groups can occur for example as part of a hertocyclic ring system as in 2-mercaptoimidazole or in an alkyl side chain as in l-allyl-2-thiourea, (2) aromatic substituents; typical compounds of this type are benzo or phenyl derivatives, (3) donor atoms containing 2 nonbonding electron pairs; typical preferred groups of this type are S-S and the like.
  • the silver complexing agents of this invention can be additionally characterized as compounds which are soluble in water at 70F. in'concentration of at least l0' and preferably 10 moles per liter and wherein said compounds are capable of forming a silver ion complex in a ratio of at least 10 silver ion to 10 complexing agent on a molar basis in the presence of an equal molar or excess of silver ion as measured by potentiometric titration.
  • the silver complexing agents of this invention are incorporated in the developing solutions in lower concentrations than normally used for antifoggant purposes.
  • the developing solution is used directly after imagewise exposure or photodevelopment it is critical to maintain the concentration level of the silver complexing agent at levels below 2X10 moles per liter of solution and preferably below 1.5Xl0 moles per liter of developing solution.
  • the concentrations of the silver complexing agent for this embodiment are maintained between about 10 moles to about 2Xl0 moles per liter about 1X10 moles to about 1 5X10 moles per liter.
  • the concentration of the silver complexing agent can be generally'from about l0" moles to about 4X10" moles and preferably from about 10" moles to not more than 2.5)(10 moles i solution. If the concentrations of the silver complexing agent exceed the above concentrations, the density of the developed image is greatly reduced.
  • direct-print compositions are stabilized ordeveloped by contacting said compositions with -a bleach bath and then contacting said compositions withthe developing solutions containing the silver complexing agentsXHowever, the bleach bath will also provide some improvements in image properties in directprint emulsions when said bleach bath is followed with other developing solutions.
  • Typical compounds which can be characterized by the above tests and are effective in the developing baths of this invention are Z-mercaptothiazole, Z-mercapto benzothiazole, 2- mercapto-6-nitrobenzothiazole, 4-carboxymethyl-4- thiazoline-Z-thione, thiazolidine-Z-thione, irnidazole, 2- benzimidazoletliiol, 5-amino-Z-benzimidazolethiol, 2-mercaptoimidazole, l-methyl-2-mercaptoimidazole, Z-mercaptopyrimidine, dithiourazole, o-aminobenzenethiol, o-mercapto-benzoic acid, l-phenyl-2-mercaptotetrazole, l-phenyl-2- thiourea, S-nitrobenzimidazolethiol, 6-amino-2-mercaptobenzothiozole, 2-benzoxazolethiol
  • the silver halide emulsions which can be processed according to this invention contain small amounts of compounds which have the characteristics of the above silver complexing agents. This is often the case with directprint materials wherein halogen acceptors of this type are used in the compositions.
  • the halogen acceptor concentration which is utilized to provide optimum image characteristics in a direct-print emulsion upon photodevelopemnt is generally too low to successfully provide the necessary image properties in a surface developer when permanizing the image record.
  • the image record in direct-print emulsions containing these compounds as halogen acceptors are greatly improved by the use of the indicated concentrations of the silver complexing agent in the surface developer baths according to this invention.
  • the bleach baths which can be used in certain preferred embodiments of this invention include baths containing oxidizing agents such as, for example, those disclosed in The Journal of Photographic Science, Vol. 9, 1961, pp. 217-222.
  • oxidizing agent concentrations of baths used in this invention is from about onegram/liter to about 100gram/liter and preferably from about 5 grams to about 50 grams per liter.
  • the developing bath comprises any of the conventional developing agents used for surfaces development of photographic records.
  • Typical developing agents include hydroquinone, ascorbic acid, l-hydroxy-Z-methylaminobenzene, catechol, pyrogallol, l-phenyl-3-pyrazolidone, para-hydroxyphenyl-aminoacetic acid, t-butyl-hydroquinone, 4-methyl-4-hydroxymenthyl- 1 -phenyl-3-pyrazolidone and the like.
  • the developing baths of this invention are substantially free of strong silver halide solvents or fixing agents such as water soluble thiocyanates and thiosulfates such as potassium thiocyanate and sodium thiosulfate.
  • strong silver halide solvents such as water soluble thiocyanates and thiosulfates such as potassium thiocyanate and sodium thiosulfate.
  • the silver halide compositions which can be stabilized or developed according to this invention are those which are internally sensitive to electromagnetic radiation, i.e., light, X- rays, electrons, etc.
  • Suitable silver halides include internally sensitive silver bromide, silver bromoiodide, silver chlorobromide, silver chlorobromoiodide, and the like.
  • the preferred emulsions are those wherein the silver halide is predominately silver bromide.
  • preferred emulsions according to this invention have higher internal sensitivity than surface sensitivity.
  • Typical suitable emulsions are disclosed in Davey et al., U.S. Pat. No. 2,592,250 issued Apr. 8, 1952; U.S. Pat. No.
  • internal image emulsions can be used in the invention, such having silver halide grains wherein a predominant amount of the sensitivity is internal to the grains.
  • Such internal image emulsions are those which, when measured according to normal photographic techniques by coating a test portion of the emulsion on a transparent support, exposing to a light intensity scale having a fixed time between 1X10" and 10 second, bleaching 5 minutes in a 0.3 percent potassium ferricyanide solution at 65 F., and then developing in Developer Z below (an "intemal-type developer), have a sensitivity measured at a density of 0.1 above fog, greater than the sensitivity of an identical test portion which has been exposed in the same way and developed for 6 minutes at 68 F. in Developer X below (a surface-type" developer).
  • the direct-print emulsions which can be stabilized in accordance with this invention generally contain halogen acceptors, for example, nitrogen containing halogen acceptors such as those disclosed in McBride, U.S. Pat. No. 3,287,137 and McBride, U.S. Pat. No. 3,271,157.
  • halogen acceptors for example, nitrogen containing halogen acceptors such as those disclosed in McBride, U.S. Pat. No. 3,287,137 and McBride, U.S. Pat. No. 3,271,157.
  • watersoluble halides to the silver halide emulsion after its precipitation but before it is coated. More generally, about 1 to about 50 mole percent, and preferably about 1 to about 10 mole percent of water soluble halide based on the silver halide in the emulsion is used.
  • the stabilizing or developing baths of this invention can also be used to treat other silver halide systems, such as developing out system, etc., if desired to maintain or improve image proparties in said systems.
  • colloids can be used as vehicles or binding agents in preparing the silver halide emulsions of this invention.
  • Satisfactory colloids which can be used for this purpose include any of the hydrophilic colloids generally employed in the photographic field including, for example, gelatin, colloidal albumin, polysaccharides, cellulose derivatives, synthetic resins such as polyvinyl compounds, including polyvinyl alcohol derivatives, acrylamide polymers and the like.
  • the vehicle or binding agent can also contain hydrophobic colloids such as dispersed polymerized vinyl compounds, particularly those which increase the dimensional stability of photographic materials. Suitable compounds of this type include water-soluble polymers of alkyl acrylates or methacrylates, acrylic acid, sulfoalkyl acrylates or methacrylates, and the like.
  • Typical supports for photographic elements of the invention include glass, metal, paper, polyolefin-coated paper, cellulose nitrate film, cellulose acetate film, polystyrene film,
  • polyester films such as polyethylene terephthalate film, heat resistant polymeric films such as high temperature polyester, polyimide, polycarbonate films, and the like.
  • the essential ingredients of the stabilizing compositions according to the invention namely the developing agents, the selective silver complexing agent and in some embodiments,
  • the bleach can be prepackaged in a kit, diluted, concentrated, or in powder form and can be either mixed together or packaged individually for use in the systems of this invention.
  • the respective compositions are generally prepackaged in- EXAMPLE 2 Samples of direct-print silver. halide emulsions prepared according to example I] of Kitze, Belgian Pat. No. 689,515 issued Jan. [3, i967, are imagewise exposed to a step tablet on dividually and can be readily added to aqueous alkaline solu- 5 a sensitometer b ex f l0 tion or water to from th necessary baths.
  • kits prepared for making stabilizing composiphotodeveglo b ex gq z es s subsequently tions comprising the essential ingredients of this invention are illumination g 2 L d f i efci'of fluorescent contemplated to be within the scope of-this invention.
  • th b k ens o t e area and r 0 e ac ground area are shown ln-table l.
  • the invention can be further illustrated by the following ex- 0 f am lcs 0 the p isamples is processed as a con- P trol sample in Developer B for 60 seconds, then stopped for 10 seconds, fixed for 5 minutes and washed for 5 minutes.
  • the ima e record EXAMPLE 1 g densities obtained for this pro are shown m 2 L-.. strips of a direct-print silver halide emulsion prepared according to example Id of McBride US. Pat. No. 3,287,l36 are DEVELOPER B imagewise exposed to a step tablet on a sensitometer by exposing for 10'' second to a high intensity Xenon light.
  • the respec- 1 tive samples are subsequently photodeveloped by exposing to r i 8-" 250 foot-candles of daylight fluorescent illumination for g ming: 3" seconds to produce a negative image with about 0.4 density Sodium carbonate so discrimination Potassium bromide 2
  • Developer A described below, for 60 seconds, then stopped in acetic acid for l0 seconds, fixed for 2 minutes in sodium thiosulfate solution and Several additional'nonphotodeveloped and photodeveloped washed for 5 minutes in running water.
  • samples are processes in Developer B containingvthe concen- A second sample is processed by the above procedure trations of selective silver complexing agents indicated in table wherein Developer A additionally contains 0.1 g./l. ofl -phenl.
  • the densities of the image area obtained upon development yl-S-mercaptoterazole. 30 are recorded in table I.
  • a bleach bath is preferably used when processing a directprint emulsion prior to processing in the developer containing selective silver complexing agents.
  • a control sample is processed in Developer A for 2 minutes, Sodium Sfllfiw 500 fixcd for 5 minutes and washed in running water.
  • a second odlum carbonate 80.0 g. sample of the above emulsion IS processed in Developer C acpomsium bmmidc 2,0 I cording to the same processing procedure.
  • the combination of the bleach bath and the developer con- The normal surface developer produced a negative image taining the selective silver complexing agents produces lower with high background density; while the bleach process folminimum density with better image discrimination than the lowed by the developer containing the selective silver comdeveloper containing the selective silver complexing agents plexing agent greatly reduced the background and maintained alone or the bleach followed b the conventional surface equivalent image discrimination.
  • the resulting image developer. produced by the bleach process followed by the developer containing the selective silver complexing agent provides :1 TABLE ll record which is much more discernible to the eye as the image density is on a percentage basis much darker than the A background density.
  • sample A of a similar emulsion is prepared by the same procedure with the addition of Samples of direct-print silver halide emulsions prepare l5g./mole of silver of Z-mercaptoimidazole incorporated in ng l0 example 4 0f KaTlSOn, gi 705.036 the emulsion coating. Samples of the respective coatings are sued Nov.
  • Nmethyl-para-amlnophenul 4.5 g. DEVELOPER F mas Sodium sulfite 50.0 g. Hydroquinnne 9.0 g. I Sodium carbonate 80.0 g. yl'p p 8 Potassium bromide 2.0 g. Hydwqumonc sw m I m" Sodium sulfite 45.0 g. Sodium carbonate 80.0 g.
  • the selective silver complexing agent utilized in the emulsion shows an improvement in discrimination over the process without agent present.
  • the addition of the selective silver complexing agent in the developer in addition to the use of the same or a similar compound in the emulsion coating shows an additional improvement in the image discrimination obtained after processing.
  • a process for developing and stabilizing image records in an internal image silver halide compositions which has been imagewise exposed comprising contacting said silver halide composition with a surface developingsolution, said solution comprising a developing agent and from moles/liter to about 2X10 moles/liter of a silver complexing agent, said complexing agent containing at least one group capable of forming covalent bonds with silver said group selected from mercaptan groups, imide groups, or tautometers thereof and at least one secondary bonding group capable of forming pibonds, said secondary bonding group consisting of I l 1 i groups.
  • a process according to claim 2 wherein said silver complexing agent is 2-mercaptoimidaz'ole.
  • said silver complexing agent is selected from the group consisting of 2-mercaptothiazole, Z-mercapto benzothiazole, 2-mercapto-6- nitrobenzothiazole, 4-carboxymethyl-4-thiazoline-2-thione, thiazolidine-Z-thione, imidazole, 2-benzimidazolethiol, 5- amino-2-benzimidazolethiol, Z-mercaptoimidazole, l-methyl- Z-mercaptoimidazole, 2-mercaptcpyrimidine, dithiourazole,
  • o-aminobenzenethiol o-mercaptobenzoic acid, l-phenyl-2- mercaptotetrazole, l-phenyl-2thiourea, 5- nitrobenzimidazolethiol, 6-amino-Z-mercaptobenzothiozole, 2-benzoxolethiol, 5-methyl-2-oxazolidinethione, 4- aminophenyl-disulfide and l-allyl-2-thiourea.
  • a process according to claim 4 wherein said silver complexing agent is selected for the group consisting of l-allyl-2- thiourea, Z-mercaptoimidazole, dithiourazole, and l-phenyl- Smercaptotetrazole.
  • a process according to claim 4 wherein said silver complexing agent is 2-mercaptoimidazole, in a concentration of from lXlO to about l.5 l0 moles/liter.
  • a process for stabilizing image records in light developable internal image silver halide compositions which have been imagewise exposed and photodeveloped to produce a visible image therein comprising (1) contacting said silver halide composition with a silver halide bleaching solution, and then (2) contacting said silver halide with a surface developing solution comprising a developing agent and from about l0 to about 4X10 moles/liter of a silver complexing agent comprising at least one group capable of forming covalent bonds with silver, said groups selected from mercaptan groups, imide groups, or tautomers thereof and at least one secondary bonding group capable of forming pi-bonds, said secondary bonding group consisting of groups.
  • said silver complexing agent is selected from a group consisting of 2-mercaptothiazole, Z-mercapto benzothiazole, 2-mercapto-6- nitrobenzthiazole, 4-carboxymcthyl-4-thiazoline-2-thione, thiazolidine-Z-thione, imidazole, 2-benzimidazolethiol, 5- amino-2benzimidasolethiol, 2-mercaptoimidazole, l-methyl- 2-mercaptoimidazole, Z-mercaptopyrimidine, dithiourazole, o-aminobenzenethiol, o-mercaptobenzoic acid, l-phenyl-2- mercaptotetrazole, l-phenyl-Z-thiourea, 5 nitrobenzimidazolethiol, o-amino-2-mercaptobenzothiozole, 2-benzoxazolethiol, 5-methyl-2-oxazolinethione
  • said silver complexing agent is selected from the group consisting of l-allyl- 2thiourea, Zmercaptoimidazole, dithiourazole, and l-phenyl- S-mercaptotetrazole.
  • bleaching solution comprises potassium dichromate
  • silver complexing agent comprises Z-mercaptoimidazole
  • a process according to claim 7 wherein said groups capable of forming covalent bonds with silver consists of mercaptan groups.
  • a process according to claim 7 wherein said silver complexing agent is Z-mercaptoimidazole.
  • said silver complexing agent is compound which is soluble in water in a concentration of at least 10" moles/liter at 70 F. and wherein said compound is capable of forming a silver complex having a ratio of at least 1 silver ion to 1 silver complexing agent in a molar basis in the presence of excess silver ions as measured by potentiometn'c titration.
  • Claim 1 line 5 "10 should read O line 6, "2x1 0 should read --2x

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
US731275A 1968-05-22 1968-05-22 Surface developer with heterocyclic mercaptan for use on internal image emulsion Expired - Lifetime US3615511A (en)

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BE (1) BE733492A (de)
DE (1) DE1923824A1 (de)
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3852071A (en) * 1971-11-09 1974-12-03 Fuji Photo Film Co Ltd Process of producing positive images
DE2518015A1 (de) * 1974-04-23 1975-11-13 Polaroid Corp Photographische entwickler, verfahren und aufzeichnungsmaterialien
US4126459A (en) * 1976-05-14 1978-11-21 Polaroid Corporation Thioether substituted silver halide solvents
US4211562A (en) * 1974-04-23 1980-07-08 Polaroid Corporation Photographic compositions with silver halide solvents containing thioether groups
US5998110A (en) * 1996-12-11 1999-12-07 Ferrania S.P.A. Photographic silver halide developer composition and process for forming photographic silver images
EP1191395A1 (de) * 2000-08-21 2002-03-27 Eastman Kodak Company Ascorbinsäureentwicklerzusammensetzungen und Verfahren zu ihrer Verwendung

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3852071A (en) * 1971-11-09 1974-12-03 Fuji Photo Film Co Ltd Process of producing positive images
DE2518015A1 (de) * 1974-04-23 1975-11-13 Polaroid Corp Photographische entwickler, verfahren und aufzeichnungsmaterialien
US4211562A (en) * 1974-04-23 1980-07-08 Polaroid Corporation Photographic compositions with silver halide solvents containing thioether groups
US4126459A (en) * 1976-05-14 1978-11-21 Polaroid Corporation Thioether substituted silver halide solvents
US5998110A (en) * 1996-12-11 1999-12-07 Ferrania S.P.A. Photographic silver halide developer composition and process for forming photographic silver images
EP1191395A1 (de) * 2000-08-21 2002-03-27 Eastman Kodak Company Ascorbinsäureentwicklerzusammensetzungen und Verfahren zu ihrer Verwendung

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GB1275074A (en) 1972-05-24
FR2009092A1 (de) 1970-01-30
DE1923824A1 (de) 1969-12-11
BE733492A (de) 1969-07-31

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