US3598598A - Fog stabilizers for photographic emulsions - Google Patents

Fog stabilizers for photographic emulsions Download PDF

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Publication number
US3598598A
US3598598A US764332A US3598598DA US3598598A US 3598598 A US3598598 A US 3598598A US 764332 A US764332 A US 764332A US 3598598D A US3598598D A US 3598598DA US 3598598 A US3598598 A US 3598598A
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Prior art keywords
silver halide
thionamide
photographic
fog
group
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US764332A
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English (en)
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Arthur H Herz
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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
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/34—Fog-inhibitors; Stabilisers; Agents inhibiting latent image regression
    • G03C1/346—Organic derivatives of bivalent sulfur, selenium or tellurium
    • 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

  • Thionamides have been used in the past as antifoggants in silver halide emulsions. Such compounds generally contain at least one hydrogen atom on the amidic nitrogen and exist in tautomeric equilibria between the thione and sulfhydryl structure. However, these compounds have a propensity to desensitize fast silver halide emulsions and, therefore, are generally used in concentrations of less than 50 milligrams per mole of silver to prevent objectionable loss of emulsion sensitivity.
  • a fog stabilizing amount of an acrylic or monocyclic thionamide, said thionamide containing at least one acid group which will confer a negative charge to the thionamide at a pH of 5 or below is incorporated into the silver halide emulsion of aphotographic element or in a layer contiguous to the silver halide emulsion.
  • a photographic element comprising a support coated with at least one silver halide emulsion layer is developed in the presence of one of the previously described thionamides.
  • the thionamide is present in the photographic element but it can be present elsewhere in the systeme.g., in the developer.
  • thionamides which can be used in the practice of this invention are 3-substituted thiazoline-2 thiones which have the structure wherein R is an aliphatic group, e.g., an alkyl chain containing up to 10 carbon atoms which can be substituted with one or more groups such as carboxyl, sulfonyl, etc.; R and R can each be hydrogen, an aliphatic or substituted aliphatic radical, e.g., a keto group, a carboxyl group or an alkyl group containing up to 10 carbon atoms, which alkyl group can be further substituted with one or more other groups such as carboxyl, sulfonyl, hydroxy, an ester group, etc.; and at least one of R R and R contains an acid substituent such as a carboxylic or sulfonic acid group.
  • R is an aliphatic group, e.g., an alkyl chain containing up to 10 carbon atoms which can be substitute
  • a further group of thionamides which can be used are N,N,N,N'-tetrasubstituted thioureas having the structure groups containing an acid substituent such as a carboxylic or sulfonic acid group.
  • the thionamide can be incorporated into the silver halide emulsion of a photographic element or in a layer contiguous to the silver halide emulsion in any amount which Will stabilize the silver halide emulsion against fog.
  • a concentration of the thionamide in an amount of from about 0.05 to about 30, preferably about 0.6 to about 10.0 grams per mole of silver in the silver halide emulsion can be used with good results.
  • the preparation of photographic silver halide emulsions such as are suitably stabilized with the thionamide typically involves three separate operations: (1) emulsification and digestion of silver halide, (2) the freeing of the emulsion of excess water-soluble salts, suitably by washing with water, and (3) the second digestion or after-ripening to obtain increase demulsion speed or sensitivity.
  • the thionamide can 'be added to the emulsion before the final digestion or after-ripening or it can be added immediately prior to the coating.
  • the silver halide emulsion of a photographic element containing the antifoggants of this invention can contain conventional addenda such as gelatin plasticizers, coating aids, and hardeners such as aldehyde hardeners, e.g., formaldehyde, mucochloric acid, glutaraldehyde bis(sodium bisulfite), maleic dialdehyde, aziridines, dioxane derivatives and oxypolysaccharides.
  • Spectral sensitizers which can be used are the cyanines, merocyanines, complex (trinuclear) cyanines, complex (trinuclear) merocyanines, styryls, and hemicyanines.
  • Sensitizing dyes useful in sensitizing such emulsions are described, for example, in US. Pats. 2,526,632 of Brooker and White issued Oct. 24, 1950, and 2,503,776 of Sprague issued Apr. 11, 1950. Developing agents can also be incorporated into the silver halide emulsion if desired or can be contained in a contiguous layer.
  • Various silver salts can be used as the sensitive salt such as silver bromide, silver iodide, silver chloride, or mixed silver halides such as silver chlorobromide, silver bromoiodide and the like.
  • the silver halides used can be those which form latent images predominantly on the surface of the silver halide grains or those which form latent images inside the silver halide crystals such as described in US. Pat. 2,592,250 of Davey and Knott issued Apr. 8, 1952.
  • the silver halide emulsion layer of a photographic element containing the antifoggants of the invention can contain any of the hydrophilic, water-permeable binding materials suitable for this purpose. Suitable materials include gelatin, colloidal albumin, polyvinyl compounds, cellulose derivatives, acrylamide polymers, etc. Mixtures of these binding agents can also be used.
  • the binding agents for the emulsion layer of the photographic element can also contain dispersed polymerized vinyl compounds. Such compounds are disclosed, for example, in US. Pats. 3,142,568 of Nottorf issued July 28, 1964; 3,193,386 of White issued July 6, 1965; 3,062,674 of Houck, Smith and Yudelson issued Nov.
  • the silver halide emulsion of a photographic element containing the antifoggants of the invention can be coated on a wide variety of supports.
  • Typical supports are cellulose nitrate film, cellulose ester film, polyvinyl acetal film, polystyrene film, poly(ethylene terephthalate) film and related films or resinous materials as well as glass, paper, metal and the like.
  • Supports such as paper which are coated with a-olefin polymers, particularly polymers of a-olefins containing two or more carbon atoms, as exemplified by polyethylene, polypropylene, ethylenebutene copolymers and the like can also be employed.
  • sensitometric characteristics of the photographic emulsions containing the antifoggants of the invention can be further enchanced by including in the emulsions a variety of hydrophilic colloids such as carboxymethyl protein of the type described in U.S. Pat. 3,011,890 of Gates, Jr., Miller and Koller issued Dec. 5, 1961, and polysaccharides of the type described in Canadian Pat. 635,206 of Koller and Russell issued Jan. 23, 1962.
  • hydrophilic colloids such as carboxymethyl protein of the type described in U.S. Pat. 3,011,890 of Gates, Jr., Miller and Koller issued Dec. 5, 1961, and polysaccharides of the type described in Canadian Pat. 635,206 of Koller and Russell issued Jan. 23, 1962.
  • Photographic emulsions containing the antifoggants of the invention can also contain speed-increasing compounds such as quaternary ammonium compounds, polyethylene glycols or thioethers. Frequently, useful effects can be obtained by adding the aforementioned speed-increasing compounds to the photographic developer solutions instead of, or in addition to, the photographic emulsions.
  • speed-increasing compounds such as quaternary ammonium compounds, polyethylene glycols or thioethers.
  • Photographic elements containing the antifo ggants of the instant invention can be used in various kinds of photographic systems. In addition to being useful in X-ray and other non-optically sensitized systems, they can also be used in orthochromatic, panchromatic and infrared sensitive systems.
  • the sensitizing addenda can be added to photographic systems before or after any sensitizing dyes which are used.
  • Silver halide emulsions containing the antifoggants of the invention can be used in color photography, for example, emulsions containing color-forming couplers or emulsions to be developed by solutions containing couplers or other color-generating materials, emulsions of the mixed-packet type such as described in U.S. Patent 2,698,- 794 of Godowsky issued J an. 4, 1955; in silver dye-bleach systems; and emulsions of the mixed-grain type such as described in U.S. Pat. 2,592,243 of Carroll and Hanson issued Apr. 8, 1952.
  • Silver halide emulsions containing the antifoggants of the invention can be sensitized using any of the wellknown techniques in emulsion making, for example, by digesting with naturally active gelatin or various sulfur, selenium, tellurium compounds and/or gold compounds.
  • the emulsions can also be sensitized with salts of noble metals of Group VIII of the Periodic Table which have an atomic weight greater than 100.
  • Silver halide emulsions containing the antifoggants of the invention can be used in diffusion transfer processes which utilize the undeveloped silver halide in non-image areas of the negative to form a positive by dissolving the undeveloped silver halide and precipitating it on a receiving layer in close proximity to the original silver halide emulsion layer.
  • diffusion transfer processes which utilize the undeveloped silver halide in non-image areas of the negative to form a positive by dissolving the undeveloped silver halide and precipitating it on a receiving layer in close proximity to the original silver halide emulsion layer.
  • the emulsions can also be used in diffusion transfer color processes which utilize a diffusion transfer of an imagewise distribution of developer, coupler or dye, from a lightsensitive layer to a second layer, while the two layers are in close proximity to one another.
  • Silver halide emulsions containing the antifoggants of the invention can be processed in stabilization processes such as the ones described in U.S. Pat. 2,614,927 of Broughton and Woodward issued Oct. 21, 1952, and as described in the article Stabilization Processing of Films and Papers by H. D. Russell, E. C.
  • antifoggants of the invention While it is preferred to utilize the antifoggants of the invention by incorporating them directly into a photographic element, the antifoggants could also be utilized by incorporating them into a photographic developer to control development fog.
  • the antifogging agents of this invention can be incorporated to advantage during manufacture in silver halide emulsions representing the variations described above. Moreover, fog control in binderless silver halide films prepared by vapor deposition of silver halide on a suitable support can be achieved by coating the antifogging agents of the invention over the vapor deposited layer of silver halide.
  • the antifoggant action of the thionamide compounds of this invention are particularly advantageous, their ability to complex with metal ions, especially with silver ions, warrants their use in numerous photographic systems.
  • they can be utilized in silver halide diffusion transfer systems; as silver halide grain growth agents to promote Ostwald ripening; as fixing agents; and as stabilization agents for unexposed silver halide in stabilization processing systems as described, for example, in Broughton et al. U.S. Patent 2,614,927 issued October 21, 1952.
  • the thiones of this invention can also be used to form intramolecular salts or chelates with silver ions which, when coated in a suitable binder on a suitable support form light-sensitive layers as described in copending application Ser. No.
  • these silverthione complexes allow them to be utilized with lightsenstive catalysts, which can or cannot be photoconductors, in a bifunctional photographic element containing two light-sensitive components which can be treated selectively to produce two independent images.
  • these silver complexes can be utilized in image reproduction systems in combination with a reducing agent and a light-sensitive catalyst as described in Shepard et al. U.S. Pat. 3,152,903 issued Oct. 13, 1964.
  • the stabilizer compound is neutralized by the addition of a base before addition to the emulsion where it is necessary to maintain the pH of the emulsion constant.
  • iodide emulsion containing a spectral sensitizer Each :8g: 6 3; g; g g emulsion sample is coated on a cellulose acetate film support at a coverage of 350 milligrams of silver and 840 u 30 milligrams of gelatin per square foot.
  • the photographic thionamide which does not contain an and substituent. results obtained from these tests are listed in Table 3.
  • EXAMPLE 2 EXAMPLE 4 1 Process of Example 1 is repeatefi except that the 5 The process of Example 3 is repeated substituting for stabllizer compounds added to the emulsions have the forthe Stabilizer compounds therein a thionamide having the mula formula 8 s r mo CHzOzC-l HsC-KlTI/ HaC- wherein R is defined in Table 2.
  • the emulsions also contain a spectral sensitizer and, in several samples, an 60 In several samples, an additional compound as indicated additional compound or compounds as indicated in Table in Table 4 is included. The photographic results obtained 2. Development is accomplished in Kodak Developer DK- 7 are hsted in Table 4.
  • Example 9 The process of Example 3 is repeated using as the is also tested for its ability to stabilize an emulsion.
  • the photographic results are set forth in Table 6.
  • EXAMPLE 6 This example illustrates the use of dithiocarbamates containing acid groups as stabilizers for photographic emulsions.
  • the process of Example 2 is repeated using as the stabilizer compound dithiocarbamates having the are as defined in Table 6.
  • the pyridinium salt used is 7,18-diazo-6,19 dioxotetracosane 1,24-bis(pyridinium perchlorate)
  • the results in the above tables show that the compounds of this invention prevent the growth of incubation fog when incorporated in photographic emulsions.
  • a composition comprising a silver halide emulsion containing a fog-stabilizing amount of an acylic or monocyclic thionamide, said thionamide containing at least one carboxylic or sulfonic acid group which will confer a negative charge to the thionamide at a pH of 5 or below.
  • composition of claim 11 wherein said thionamide is present in an amount of about 005 gram to about 30.0 grams per mole of silver in said silver halide emulsion.
  • composition of claim 1 wherein said thionamide has the structure wherein X is sulfur, oxygen or an iso'electronic group, R R and R when taken separately, are aliphatic groups having up to 10 carbon atoms or substituted aliphatic groups, R and R when taken together, represent an alkylene group and R and R when taken together with the nitrogen atom to which they are attached, represent a heterocyclic group.
  • a photographic element comprising a support coated with a silver halide layer, said element containing a fog-stabilizing amount of an acylic or monocyclic thionamide, said thionamide containing at least one carboxylic or sulfonic acid group which will confer a negative charge to the thionamide at a pH of 5 or below.
  • said thionamide has the structure wherein X is sulfur, oxygen or an iso-electronic group, R R and R when taken separately, are aliphatic groups having up to 10 carbon atoms or substituted aliphatic groups, R and R when taken together, represent an alkylene group and R and R when taken together with the nitrogen atom to which they are attached, represent a heterocyclic group.
  • said thionamide has the structure wherein R is an aliphatic group or a substituted aliphatic group containing up to 10 carbon atoms and R and R are hydrogen, aliphatic groups or substituted aliphatic groups containing up to 10 carbon atoms, at least one of said groups containing a carboxylic or sulfonic acid substituent.
  • X in said thionamide represents the group NR, R being an aliphatic or substituted aliphatic group having up to 10 carbon atoms, and at least one of said groups R, R R and R contains a carboxylic or sulfonic acid substituent.
  • said thionamide has the structure wherein R is an aliphatic group or a substituted aliphatic group containing up to 10 carbon atoms and R and R are hydrogen, aliphatic groups or substituted aliphatic groups containing up to 10 carbon atoms, at least one of said groups containing a car-boxylic or sulfonic acid substituent.
  • X in said thionamide represents the group -NR, R being an aliphatic or substituted aliphatic group having up to 10 carbon atoms, and at least one of said groups R, R R and R contains a carboxylic or sulfonic acid substituent.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Heterocyclic Carbon Compounds Containing A Hetero Ring Having Nitrogen And Oxygen As The Only Ring Hetero Atoms (AREA)
US764332A 1968-10-01 1968-10-01 Fog stabilizers for photographic emulsions Expired - Lifetime US3598598A (en)

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2263808A1 (de) * 1971-12-28 1973-07-05 Fuji Photo Film Co Ltd Lichtempfindliches silberhalogenidmaterial
US3854954A (en) * 1970-09-01 1974-12-17 Agfa Gevaert Ag Silver halide emulsion containing a stabilizing combination of an azaidene and a n,n-dialkyl-dithiocarbamic acid ester
US4001020A (en) * 1971-03-04 1977-01-04 Fuji Photo Film Co., Ltd. Developing a silver ha1ide emulsion in contact with a heterocyclic thione and a polyalkylene oxide
US4126463A (en) * 1976-09-14 1978-11-21 Agfa-Gevaert Aktiengesellschaft Method of stabilizing photographic silver halide emulsion layers
US4138265A (en) * 1977-06-27 1979-02-06 Eastman Kodak Company Antifoggants in certain photographic and photothermographic materials that include silver salts of 3-amino-1,2,4-mercaptotriazole
US4263396A (en) * 1974-04-06 1981-04-21 Agfa-Gevaert Ag Direct-positive photographic material
US4749646A (en) * 1987-03-23 1988-06-07 Eastman Kodak Company Silver halide photosensitive materials containing thiourea and analogue derivatives
US4810626A (en) * 1987-02-25 1989-03-07 Eastman Kodak Company Silver halide photosensitive materials containing thiourea and analogue compounds
US5246826A (en) * 1992-05-08 1993-09-21 Eastman Kodak Company Process of preparing photosensitive silver halide emulsions
US5246825A (en) * 1992-05-08 1993-09-21 Eastman Kodak Company Preparation of photosensitive silver halide materials with organic ripening agents
US5246827A (en) * 1992-05-08 1993-09-21 Eastman Kodak Company Preparation of photosensitive silver halide materials with a combination of organic ripening agents
EP0786690A2 (en) 1996-01-26 1997-07-30 Eastman Kodak Company Silver halide light sensitive emulsion layer having enhanced photographic sensitivity
US6043013A (en) * 1998-01-29 2000-03-28 Eastman Kodak Company Color photographic element containing elemental silver and heterocyclic thiol in a non-light sensitive layer
US20160177056A1 (en) * 2014-12-17 2016-06-23 Dura Chemicals, Inc. Compositions Containing an Oxime-Free Anti-Skinning Agent, and Methods for Making and Using the Same

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BR7100500D0 (pt) * 1970-03-20 1973-06-07 Eastman Kodak Co Elemento fotografico
JPS6011341B2 (ja) * 1977-05-23 1985-03-25 富士写真フイルム株式会社 ハロゲン化銀写真乳剤
JP2002534499A (ja) * 1999-01-15 2002-10-15 アトフィナ 界面活性剤と重合開始剤の両方の役目をする化合物を用いた乳化重合

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3854954A (en) * 1970-09-01 1974-12-17 Agfa Gevaert Ag Silver halide emulsion containing a stabilizing combination of an azaidene and a n,n-dialkyl-dithiocarbamic acid ester
US4001020A (en) * 1971-03-04 1977-01-04 Fuji Photo Film Co., Ltd. Developing a silver ha1ide emulsion in contact with a heterocyclic thione and a polyalkylene oxide
DE2263808A1 (de) * 1971-12-28 1973-07-05 Fuji Photo Film Co Ltd Lichtempfindliches silberhalogenidmaterial
US4263396A (en) * 1974-04-06 1981-04-21 Agfa-Gevaert Ag Direct-positive photographic material
US4126463A (en) * 1976-09-14 1978-11-21 Agfa-Gevaert Aktiengesellschaft Method of stabilizing photographic silver halide emulsion layers
US4138265A (en) * 1977-06-27 1979-02-06 Eastman Kodak Company Antifoggants in certain photographic and photothermographic materials that include silver salts of 3-amino-1,2,4-mercaptotriazole
US4810626A (en) * 1987-02-25 1989-03-07 Eastman Kodak Company Silver halide photosensitive materials containing thiourea and analogue compounds
US4749646A (en) * 1987-03-23 1988-06-07 Eastman Kodak Company Silver halide photosensitive materials containing thiourea and analogue derivatives
US5246826A (en) * 1992-05-08 1993-09-21 Eastman Kodak Company Process of preparing photosensitive silver halide emulsions
US5246825A (en) * 1992-05-08 1993-09-21 Eastman Kodak Company Preparation of photosensitive silver halide materials with organic ripening agents
US5246827A (en) * 1992-05-08 1993-09-21 Eastman Kodak Company Preparation of photosensitive silver halide materials with a combination of organic ripening agents
EP0786690A2 (en) 1996-01-26 1997-07-30 Eastman Kodak Company Silver halide light sensitive emulsion layer having enhanced photographic sensitivity
US6043013A (en) * 1998-01-29 2000-03-28 Eastman Kodak Company Color photographic element containing elemental silver and heterocyclic thiol in a non-light sensitive layer
US20160177056A1 (en) * 2014-12-17 2016-06-23 Dura Chemicals, Inc. Compositions Containing an Oxime-Free Anti-Skinning Agent, and Methods for Making and Using the Same
US9957374B2 (en) * 2014-12-17 2018-05-01 Dura Chemicals, Inc. Compositions containing an oxime-free anti-skinning agent, and methods for making and using the same

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FR2019603A1 (enrdf_load_stackoverflow) 1970-07-03
BE739709A (enrdf_load_stackoverflow) 1970-03-16
GB1290868A (enrdf_load_stackoverflow) 1972-09-27

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