US3499761A - Silver halide emulsions containing alkyl esters of benzimidazole carbamic acid antifogging agents - Google Patents
Silver halide emulsions containing alkyl esters of benzimidazole carbamic acid antifogging agents Download PDFInfo
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- US3499761A US3499761A US383963A US3499761DA US3499761A US 3499761 A US3499761 A US 3499761A US 383963 A US383963 A US 383963A US 3499761D A US3499761D A US 3499761DA US 3499761 A US3499761 A US 3499761A
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- United States
- Prior art keywords
- silver halide
- carbamic acid
- emulsion
- light sensitive
- antifoggant
- Prior art date
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- Expired - Lifetime
Links
- 239000000839 emulsion Substances 0.000 title description 61
- -1 Silver halide Chemical class 0.000 title description 49
- 229910052709 silver Inorganic materials 0.000 title description 39
- 239000004332 silver Substances 0.000 title description 39
- 239000003795 chemical substances by application Substances 0.000 title description 14
- BHFLSZOGGDDWQM-UHFFFAOYSA-N 1h-benzimidazole;carbamic acid Chemical compound NC(O)=O.C1=CC=C2NC=NC2=C1 BHFLSZOGGDDWQM-UHFFFAOYSA-N 0.000 title description 5
- 125000005907 alkyl ester group Chemical group 0.000 title description 3
- 239000000463 material Substances 0.000 description 18
- 229910052739 hydrogen Inorganic materials 0.000 description 9
- 239000001257 hydrogen Substances 0.000 description 9
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 9
- 239000003381 stabilizer Substances 0.000 description 8
- 108010010803 Gelatin Proteins 0.000 description 6
- 239000011248 coating agent Substances 0.000 description 6
- 238000000576 coating method Methods 0.000 description 6
- 229920000159 gelatin Polymers 0.000 description 6
- 239000008273 gelatin Substances 0.000 description 6
- 235000019322 gelatine Nutrition 0.000 description 6
- 235000011852 gelatine desserts Nutrition 0.000 description 6
- 125000000217 alkyl group Chemical group 0.000 description 5
- 150000001875 compounds Chemical class 0.000 description 5
- 125000004432 carbon atom Chemical group C* 0.000 description 4
- 230000005070 ripening Effects 0.000 description 4
- 230000035945 sensitivity Effects 0.000 description 4
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical group [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical group C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 3
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical group [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 3
- 239000002585 base Substances 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 239000000975 dye Substances 0.000 description 3
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000011591 potassium Chemical group 0.000 description 3
- 229910052700 potassium Inorganic materials 0.000 description 3
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 230000001235 sensitizing effect Effects 0.000 description 3
- 239000011734 sodium Chemical group 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- JKFYKCYQEWQPTM-UHFFFAOYSA-N 2-azaniumyl-2-(4-fluorophenyl)acetate Chemical compound OC(=O)C(N)C1=CC=C(F)C=C1 JKFYKCYQEWQPTM-UHFFFAOYSA-N 0.000 description 2
- ZVNPWFOVUDMGRP-UHFFFAOYSA-N 4-methylaminophenol sulfate Chemical compound OS(O)(=O)=O.CNC1=CC=C(O)C=C1.CNC1=CC=C(O)C=C1 ZVNPWFOVUDMGRP-UHFFFAOYSA-N 0.000 description 2
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 2
- 206010034960 Photophobia Diseases 0.000 description 2
- 229910021612 Silver iodide Inorganic materials 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 125000004494 ethyl ester group Chemical group 0.000 description 2
- 150000004820 halides Chemical class 0.000 description 2
- 208000013469 light sensitivity Diseases 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 2
- 229940045105 silver iodide Drugs 0.000 description 2
- WEYSQARHSRZNTC-UHFFFAOYSA-N 1h-benzimidazol-2-ylcarbamic acid Chemical compound C1=CC=C2NC(NC(=O)O)=NC2=C1 WEYSQARHSRZNTC-UHFFFAOYSA-N 0.000 description 1
- 102000009027 Albumins Human genes 0.000 description 1
- 108010088751 Albumins Proteins 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 125000003785 benzimidazolyl group Chemical group N1=C(NC2=C1C=CC=C2)* 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 125000001246 bromo group Chemical group Br* 0.000 description 1
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- KXDHJXZQYSOELW-UHFFFAOYSA-N carbonic acid monoamide Natural products NC(O)=O KXDHJXZQYSOELW-UHFFFAOYSA-N 0.000 description 1
- 239000005018 casein Substances 0.000 description 1
- BECPQYXYKAMYBN-UHFFFAOYSA-N casein, tech. Chemical compound NCCCCC(C(O)=O)N=C(O)C(CC(O)=O)N=C(O)C(CCC(O)=N)N=C(O)C(CC(C)C)N=C(O)C(CCC(O)=O)N=C(O)C(CC(O)=O)N=C(O)C(CCC(O)=O)N=C(O)C(C(C)O)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=O)N=C(O)C(CCC(O)=O)N=C(O)C(COP(O)(O)=O)N=C(O)C(CCC(O)=N)N=C(O)C(N)CC1=CC=CC=C1 BECPQYXYKAMYBN-UHFFFAOYSA-N 0.000 description 1
- 235000021240 caseins Nutrition 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 125000001309 chloro group Chemical group Cl* 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 239000007888 film coating Substances 0.000 description 1
- 238000009501 film coating Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 125000000959 isobutyl group Chemical group [H]C([H])([H])C([H])(C([H])([H])[H])C([H])([H])* 0.000 description 1
- 125000001449 isopropyl group Chemical group [H]C([H])([H])C([H])(*)C([H])([H])[H] 0.000 description 1
- GTCAXTIRRLKXRU-UHFFFAOYSA-N methyl carbamate Chemical compound COC(N)=O GTCAXTIRRLKXRU-UHFFFAOYSA-N 0.000 description 1
- 150000004702 methyl esters Chemical class 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 125000000740 n-pentyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229920005862 polyol Polymers 0.000 description 1
- 150000003077 polyols Chemical class 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 229920000036 polyvinylpyrrolidone Polymers 0.000 description 1
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- GGCZERPQGJTIQP-UHFFFAOYSA-N sodium;9,10-dioxoanthracene-2-sulfonic acid Chemical compound [Na+].C1=CC=C2C(=O)C3=CC(S(=O)(=O)O)=CC=C3C(=O)C2=C1 GGCZERPQGJTIQP-UHFFFAOYSA-N 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- KJAMZCVTJDTESW-UHFFFAOYSA-N tiracizine Chemical compound C1CC2=CC=CC=C2N(C(=O)CN(C)C)C2=CC(NC(=O)OCC)=CC=C21 KJAMZCVTJDTESW-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D235/00—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, condensed with other rings
- C07D235/02—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, condensed with other rings condensed with carbocyclic rings or ring systems
- C07D235/04—Benzimidazoles; Hydrogenated benzimidazoles
- C07D235/24—Benzimidazoles; Hydrogenated benzimidazoles with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached in position 2
- C07D235/30—Nitrogen atoms not forming part of a nitro radical
- C07D235/32—Benzimidazole-2-carbamic acids, unsubstituted or substituted; Esters thereof; Thio-analogues thereof
-
- 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
Definitions
- a light sensitive photographic material comprising a silver halide emulsion and an anti-foggant compound contained therein, or in a layer contiguous therewith; the anti-foggant being an alkyl ester of benzimidazole carbamic acid.
- the present invention relates, in general, to photographic materials comprising light-sensitive silver halide emulsions and, in particular, to stabilized silver halide emulsions which have less tendency to fog without substantial reduction in the light sensitivity thereof.
- Fogging in general and chemical fogging in particular may be defined as a uniform deposit of silver extending over and either partially or wholly obliterating the image and is caused in a number of ways; namely the nature of the emulsion, its age and the conditions under which it has been stored, the nature of the developer, impurities in the developing solution, and the time and temperature of the development.
- chemical fogging is also promoted when such active agents as metol are employed in a concentrated solution or are used in the presence of an excess of alkali.
- the oxidation of certain developing agents such as metol and hydroquinone exerts a powerful fogging action.
- a further object is to provide stabilizers or antifogging agents for light-sensitive silver halide emulsions which do not appreciably lower the sensitivity of the silver halide emulsions.
- Yet another object is to provide a stabilizer or antifoggant which, when added to photographic gelatin or to photographic emulsion, will prevent speed loss of the emulsion during its storage.
- a still further object is to provide stabilizers or antifogging agents for light-sensitive silver halide emulsions which do not reduce the sensitivity to light of longer wave length affected by the presence of sensitizing dyes.
- X is hydrogen, a halo radical such as chloro, fiuoro, bromo or iodo radicals and alkyl or alkoxy radicals containing less than seven carbon atoms in the alkyl group
- n is a whole positive integer of less than four
- R represents hydrogen, potassium, sodium, ammonium or lower aliphatic hydrocarbon radicals such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, or amyl
- Y represents hydrogen, chloro, nitro, methyl or ethyl radicals.
- benzimidazole-Z-car-bamic acid isoamyl ester benzimidazole-Z-carbarnic acid, hexyl ester 5-methyl-6-nitrobenzimidazole-Z-carbamie acid, hexyl ester 4,6-dichlorobenzimidazole-2-carbamic acid, propyl ester 5-fiuorobenzimidazole-Z-carbamic acid, methyl ester 4-nitrobenzimidazole-2-carbamic acid, ethyl ester 4,7-dichloro-S-methylbenzimidazole-Z-carbamic acid amyl ester 1 5,7-dimethyl-4-chlorobenzimidazole-Z-carbamic acid,
- isobutyl ester Beneficial effects in fog reduction are obtained when solutions of the antifoggant are incorporated into the silver halide emulsions as ripening finals or as coating finals. Ripening finals are added during the ripening or the sensitivity increasing stage of the emulsion making process, whereas .coating finals are added to the silver halide emulsion just prior to the coating of the emulsion on a suitable support, such as, for example, paper, glass or film.
- antifoggants can be made before,
- soluble silver salt to the soluble halide in the presence of a suitable carrier or colloid such as gelatin, polyvinyl alcohol, solubilized casein, albumin, and the like.
- a suitable carrier or colloid such as gelatin, polyvinyl alcohol, solubilized casein, albumin, and the like.
- the antifoggants of the present invention can also be employed as components of the developing solution.
- the amount of antifogging agent employed as additives to the light sensitive emulsions varies from about 0.1 to about 50 milligrams of antifoggant per 0.6 mole of silver halide.
- antifogging agents When the antifogging agents are employed as ripening finals it has been found advantageous to employ them in amounts in the range of from about 0.1 to about 25 milligrams per 0.6 mole of silver halide, whereas when the antifogging agents are employed in coating finals, it has been found advantageous to employ amounts in the range of from about 0.5 to about 50 milligrams of antifoggant per 0.6 mole of silver halide. Obviously, the development of optimum characteristics within the ranges set forth above will depend, in part, upon the type of emulsion employed and can be readily determined in each case.
- the antifogging agents of the invention it has been found advantageous to apply the antifogging agents of the invention to adjacent layers, for example, in a separate undercoating layer or in the antiabrasion gelatin surface. Alternatively, it has been found advantageous, in some cases, to apply the antifogging agents of the invention in one or all processing baths or in pre and post baths.
- antifogging agents of the invention can be compatibly employed in combination with other known antifoggants and stabilizers; with sulfur, reductionand metal-, and noble metal sensitizers as well as in combination with polyoxyalkylene polyols, their derivatives; polyvinylpyrrolidones and other accelerators.
- EXAMPLE I A silver halide emulsion in gelatin containing 2% silver iodide and 98% silver bromide was prepared in a conventional manner and brought up to its maximum light sensitivity. It was then readied for coating, finals were added, such as sensitizing dyes and hardening agents. A 0.1% solution of benzimidazole-2-carbamic acid, ethyl ester was added to the emulsion as an antifoggant and stabilizer.
- a silver halide emulsion in gelatin containing 2% silver iodide and 98% silver bromide was coated on film base in a manner known to the art. After the coating, a solution containing 20 grams of gelatin in 1 liter of H and a 0.1% solution of benzimidaz le-z-ca bamic acid.
- ethyl ester was coated thereon as an anti-abrasion layer. After drying, film samples were exposed and processed as described in Example I. The samples exhibited no speed loss in oven storage tests with a fog reduction of 0.02 compared to a speed loss from to 88 with the stabilizers presently in use.
- EXAMPLE III An emulsion was prepared and coated in the manner described in Example I, but development was carried out at a temperature of F. In this case, the type, which did not include an antifoggant, developed to a fog of 0.48, Whereas when 1 mg. of ethyl ester was used per kilo of emulsion the sample developed to a fog of only 0.28, with less speed loss than the type.
- antifogging agents which have been found to provide beneficial effects when incorporated into light sensitive silver halide emulsions can be readily prepared by known procedures such as described in US. 3,010,968, issued Nov. 28, 1961.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion, a carrier therefor and an antifoggant characterized by the general formula:
- X represents a member of the group consisting of hydrogen, chloro, fluoro, bromo, iodo and alkyl and alkoxy radicals containing less than seven carbon atoms
- n is a whole positive integer of less than four
- R represents a member selected from the group consisting of hydrogen, potassium, sodium, ammonium and aliphatic hydrocarbon radicals containing from one to six carbon atoms
- Y represents a member selected from the group consisting of hydrogen, chloro, nitro, methyl, ethyl and propyl.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, benzimidazole-Z-carbamic acid, ethyl ester.
- a light sensitive photographic material comprising a light sensitive ilver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, S-methyl- 6-nitrobenzimadazole-Z-carbamic acid, hexyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 4,6-dichlorobenzimidazole-Z-carbamic acid, propyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, S-fluorobenzimidazole-2-carbamic acid, methyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier there for, said emulsion containing, a an antifoggant, 4-nitrobenzimidazole-Z-carbamic acid, ethyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 4,7- dichloro-5-methylbenzimidazole 2 carbamic acid, amyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing as an antifoggant, 5,7-dimethyl-4-chlorobenzimidazole-Z-carbamic acid, isopropyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, S-methoxybenzimidazole-Z-carbamic acid, methyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 4,5,6,7- tetrachlorobenzimidazole-Z-carbamic acid, butyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 5,6-dichloro 4 isopropoxybenzimidazole 2 carbamic acid, methyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 5-bromo- 6-butylbenzimidazole-Z-carbamic acid, ethyl ester.
- a light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 4,5, 6,7- tetramethylbenzimidazole-Z-carbamic acid, isobutyl ester.
- a process of minimizing and preventing fog in light sensitive silver halide materials comprising a base having a light sensitive silver halide emulsion thereon, which comprises exposing said emulsion to light and developing the same in the presence of an antifoggant characterized by the formula:
- X represents a member of the group consisting of hydrogen, chloro, fluoro, bromo, iodo, :alkyl and alkoxy radicals containing less than seven carbon atoms in the alkyl group
- n is a Whole positive integer of less than four
- R represents a member selected from the group consisting of hydrogen, potassium, sodium, ammonium and aliphatic hydrocarbon radicals
- Y represents a member selected from the group consisting of hydrogen, chloro, nitro, methyl, ethyl and propyl.
Description
United States Patent 3,499,761 SILVER HALIDE EMULSIONS CONTAINING AL- KYL ESTERS 0F BENZIMIDAZOLE CARBAMIC ACID ANTIFOGGING AGENTS Fritz Dersch, Binghamton, and Sally L. Paniccia, Endwell, N.Y., assignors to GAF Corporation, New York, N.Y., a corporation of Delaware No Drawing. Filed July 20, 1964, Ser. No. 383,963 Int. Cl. G03c 1/34, 5/30 US. Cl. 96--66.5 17 Claims ABSTRACT OF THE DISCLOSURE A light sensitive photographic material comprising a silver halide emulsion and an anti-foggant compound contained therein, or in a layer contiguous therewith; the anti-foggant being an alkyl ester of benzimidazole carbamic acid.
The present invention relates, in general, to photographic materials comprising light-sensitive silver halide emulsions and, in particular, to stabilized silver halide emulsions which have less tendency to fog without substantial reduction in the light sensitivity thereof.
It is well established that light sensitive emulsions such as gelatin-silver halide emulsions are subject to fogging. Fogging in general and chemical fogging in particular may be defined as a uniform deposit of silver extending over and either partially or wholly obliterating the image and is caused in a number of ways; namely the nature of the emulsion, its age and the conditions under which it has been stored, the nature of the developer, impurities in the developing solution, and the time and temperature of the development. Additionally, chemical fogging is also promoted when such active agents as metol are employed in a concentrated solution or are used in the presence of an excess of alkali. Similarly, the oxidation of certain developing agents such as metol and hydroquinone exerts a powerful fogging action.
While a great number of antifoggants and stabilizers have been heretofore suggested as effective in preventing an increase in fogging and as a result thereof stabilize or control the keeping qualities of light sensitive silver halide emulsions, many of these compounds lower the sensitivity of silver halide emulsions and reduce the optical or dye sensitizing ability of the emulsions.
Accordingly, it is a primary object of this invention to provide stabilizers or fog inhibiting agents which tend to prevent the formation of chemical fog in light-sensitive silver halide emulsions.
A further object is to provide stabilizers or antifogging agents for light-sensitive silver halide emulsions which do not appreciably lower the sensitivity of the silver halide emulsions.
Yet another object is to provide a stabilizer or antifoggant which, when added to photographic gelatin or to photographic emulsion, will prevent speed loss of the emulsion during its storage.
A still further object is to provide stabilizers or antifogging agents for light-sensitive silver halide emulsions which do not reduce the sensitivity to light of longer wave length affected by the presence of sensitizing dyes.
Still further objects and advantages will become further apparent from the following detailed description thereof.
It has been discovered that the above objects are readily accomplished by intimately associating with silver halide emulsions certain alkyl esters of benzimidazole carbamic acids of the following formula:
Y NH
wherein X is hydrogen, a halo radical such as chloro, fiuoro, bromo or iodo radicals and alkyl or alkoxy radicals containing less than seven carbon atoms in the alkyl group, n is a whole positive integer of less than four, R represents hydrogen, potassium, sodium, ammonium or lower aliphatic hydrocarbon radicals such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, or amyl; and Y represents hydrogen, chloro, nitro, methyl or ethyl radicals.
While the above general formula is indicative of the class of benzimidazole carbamic acids operable to produce the antifogging effects observed, it is generally believed that such effects are attributable to the presence in the silver halide emulsions of the benzimidazole structure and not necessarily dependent upon the length or particular configuration of the substituents X, Y and R although their presence in the nucleus cannot entirely be discounted.
Typical and representative compounds within the scope of the general formula set forth above include:
' benzimidazole-Z-car-bamic acid, isoamyl ester benzimidazole-Z-carbarnic acid, hexyl ester 5-methyl-6-nitrobenzimidazole-Z-carbamie acid, hexyl ester 4,6-dichlorobenzimidazole-2-carbamic acid, propyl ester 5-fiuorobenzimidazole-Z-carbamic acid, methyl ester 4-nitrobenzimidazole-2-carbamic acid, ethyl ester 4,7-dichloro-S-methylbenzimidazole-Z-carbamic acid amyl ester 1 5,7-dimethyl-4-chlorobenzimidazole-Z-carbamic acid,
isopropyl ester S-methoxybenzimidazole-2-carbamic acid, methyl ester 4,5,6,7-tetrachlorobenzimidazole-2-carbamic acid, butyl ester 5,6-dichloro-4-isopropoxybenzimidazole-Z-carbamic acid;
methyl ester S-bromo-6-butylbenzimidazole-Z-carbamic acid, ethyl ester 4,5,6,7-tetramethylbenzimidazole-Z-carbamic acid,
isobutyl ester Beneficial effects in fog reduction are obtained when solutions of the antifoggant are incorporated into the silver halide emulsions as ripening finals or as coating finals. Ripening finals are added during the ripening or the sensitivity increasing stage of the emulsion making process, whereas .coating finals are added to the silver halide emulsion just prior to the coating of the emulsion on a suitable support, such as, for example, paper, glass or film.
The addition of the antifoggants can be made before,
during or after the addition of the soluble silver salt to the soluble halide in the presence of a suitable carrier or colloid such as gelatin, polyvinyl alcohol, solubilized casein, albumin, and the like.
If desired, the antifoggants of the present invention can also be employed as components of the developing solution.
The amount of antifogging agent employed as additives to the light sensitive emulsions varies from about 0.1 to about 50 milligrams of antifoggant per 0.6 mole of silver halide. When the antifogging agents are employed as ripening finals it has been found advantageous to employ them in amounts in the range of from about 0.1 to about 25 milligrams per 0.6 mole of silver halide, whereas when the antifogging agents are employed in coating finals, it has been found advantageous to employ amounts in the range of from about 0.5 to about 50 milligrams of antifoggant per 0.6 mole of silver halide. Obviously, the development of optimum characteristics within the ranges set forth above will depend, in part, upon the type of emulsion employed and can be readily determined in each case.
In some cases, it has been found advantageous to apply the antifogging agents of the invention to adjacent layers, for example, in a separate undercoating layer or in the antiabrasion gelatin surface. Alternatively, it has been found advantageous, in some cases, to apply the antifogging agents of the invention in one or all processing baths or in pre and post baths.
It has also been found that the antifogging agents of the invention can be compatibly employed in combination with other known antifoggants and stabilizers; with sulfur, reductionand metal-, and noble metal sensitizers as well as in combination with polyoxyalkylene polyols, their derivatives; polyvinylpyrrolidones and other accelerators.
The following examples will serve to illustrate the practice of the invention:
EXAMPLE I A silver halide emulsion in gelatin containing 2% silver iodide and 98% silver bromide Was prepared in a conventional manner and brought up to its maximum light sensitivity. It was then readied for coating, finals were added, such as sensitizing dyes and hardening agents. A 0.1% solution of benzimidazole-2-carbamic acid, ethyl ester was added to the emulsion as an antifoggant and stabilizer.
The so-prepared emulsion samples were coated on a suitable cellulose ester base and dried. Samples of these film coatings were then exposed in a Type IB Sensitometer and developed in a developer of the following composition:
A silver halide emulsion in gelatin containing 2% silver iodide and 98% silver bromide was coated on film base in a manner known to the art. After the coating, a solution containing 20 grams of gelatin in 1 liter of H and a 0.1% solution of benzimidaz le-z-ca bamic acid.
ethyl ester was coated thereon as an anti-abrasion layer. After drying, film samples were exposed and processed as described in Example I. The samples exhibited no speed loss in oven storage tests with a fog reduction of 0.02 compared to a speed loss from to 88 with the stabilizers presently in use.
EXAMPLE III An emulsion was prepared and coated in the manner described in Example I, but development was carried out at a temperature of F. In this case, the type, which did not include an antifoggant, developed to a fog of 0.48, Whereas when 1 mg. of ethyl ester was used per kilo of emulsion the sample developed to a fog of only 0.28, with less speed loss than the type.
The antifogging agents which have been found to provide beneficial effects when incorporated into light sensitive silver halide emulsions can be readily prepared by known procedures such as described in US. 3,010,968, issued Nov. 28, 1961.
Various modifications of the invention will occur to persons skilled in the art. Thus, it is evident in lieu of the compounds of the specific examples, any of the compounds mentioned above can be employed with similar results. Therefore, it is not intended that the invention be limited in the patent granted except as necessitated by the appended claims.
What is claimed is:
1. A light sensitive photographic material comprising a light sensitive silver halide emulsion, a carrier therefor and an antifoggant characterized by the general formula:
Y NH
wherein X represents a member of the group consisting of hydrogen, chloro, fluoro, bromo, iodo and alkyl and alkoxy radicals containing less than seven carbon atoms, n is a whole positive integer of less than four, R represents a member selected from the group consisting of hydrogen, potassium, sodium, ammonium and aliphatic hydrocarbon radicals containing from one to six carbon atoms, and Y represents a member selected from the group consisting of hydrogen, chloro, nitro, methyl, ethyl and propyl.
2. The material as defined in claim 1 wherein the antifoggant is located in the silver halide emulsion.
3. The material as defined in claim 1 wherein the antifoggant is located in a layer adjacent the silver halide emulsion.
4. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, benzimidazole-Z-carbamic acid, ethyl ester.
5. A light sensitive photographic material comprising a light sensitive ilver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, S-methyl- 6-nitrobenzimadazole-Z-carbamic acid, hexyl ester.
6. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 4,6-dichlorobenzimidazole-Z-carbamic acid, propyl ester.
7. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, S-fluorobenzimidazole-2-carbamic acid, methyl ester.
8. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier there for, said emulsion containing, a an antifoggant, 4-nitrobenzimidazole-Z-carbamic acid, ethyl ester.
9. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 4,7- dichloro-5-methylbenzimidazole 2 carbamic acid, amyl ester.
10. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing as an antifoggant, 5,7-dimethyl-4-chlorobenzimidazole-Z-carbamic acid, isopropyl ester.
11. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, S-methoxybenzimidazole-Z-carbamic acid, methyl ester.
12. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 4,5,6,7- tetrachlorobenzimidazole-Z-carbamic acid, butyl ester.
13. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 5,6-dichloro 4 isopropoxybenzimidazole 2 carbamic acid, methyl ester.
14. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 5-bromo- 6-butylbenzimidazole-Z-carbamic acid, ethyl ester.
15. A light sensitive photographic material comprising a light sensitive silver halide emulsion and a carrier therefor, said emulsion containing, as an antifoggant, 4,5, 6,7- tetramethylbenzimidazole-Z-carbamic acid, isobutyl ester.
16. A process of minimizing and preventing fog in light sensitive silver halide materials comprising a base having a light sensitive silver halide emulsion thereon, which comprises exposing said emulsion to light and developing the same in the presence of an antifoggant characterized by the formula:
wherein X represents a member of the group consisting of hydrogen, chloro, fluoro, bromo, iodo, :alkyl and alkoxy radicals containing less than seven carbon atoms in the alkyl group, n is a Whole positive integer of less than four, R represents a member selected from the group consisting of hydrogen, potassium, sodium, ammonium and aliphatic hydrocarbon radicals and Y represents a member selected from the group consisting of hydrogen, chloro, nitro, methyl, ethyl and propyl.
References Cited UNITED STATES PATENTS 3,023,103 2/1962 'Dersch et a1 96-109 3,137,578 6/1964 de Selms 96-109 3,255,202 6/1966 Johnson 96-109 3,271,154 9/1966 Dersch et al. 96-109 NORMAN G. TORCHIN, Primary Examiner R. E. FIGHTER, Assistant Examiner US. Cl. X.R. 96-109
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US38396364A | 1964-07-20 | 1964-07-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3499761A true US3499761A (en) | 1970-03-10 |
Family
ID=23515488
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US383963A Expired - Lifetime US3499761A (en) | 1964-07-20 | 1964-07-20 | Silver halide emulsions containing alkyl esters of benzimidazole carbamic acid antifogging agents |
Country Status (2)
Country | Link |
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US (1) | US3499761A (en) |
BE (1) | BE667158A (en) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3655391A (en) * | 1969-05-16 | 1972-04-11 | Paoli Merli | Azodicarbonamide fog inhibitors |
US3982947A (en) * | 1974-03-14 | 1976-09-28 | Agfa-Gevaert, N.V. | Fog-inhibitors for silver halide photography silver halide photographic material containing an iodo benzene compound as antifoggant |
US4131467A (en) * | 1977-11-23 | 1978-12-26 | E. I. Du Pont De Nemours And Company | 4,7-Dihydroxybenzimidazole hydrobromide as antifogger |
US4572892A (en) * | 1984-05-21 | 1986-02-25 | Eastman Kodak Company | Direct positive photographic elements with incorporated maximum density enhancing antifoggants |
US6245789B1 (en) | 1998-05-19 | 2001-06-12 | The Procter & Gamble Company | HIV and viral treatment |
US6265427B1 (en) | 1995-06-07 | 2001-07-24 | The Proctor & Gamble Company | Pharmaceutical composition for the method of treating leukemia |
US6271217B1 (en) | 1997-01-28 | 2001-08-07 | The Procter & Gamble Company | Method of treating cancer with a benzimidazole and a chemotherapeutic agent |
WO2001083457A2 (en) * | 2000-04-28 | 2001-11-08 | The Procter & Gamble Company | Benzimidazole-2-carbamates and their use in cancer treatment |
US6362207B1 (en) | 1995-04-12 | 2002-03-26 | The Procter & Gamble Company | Methods of treating viral infections with benzimidazoles |
US6380232B1 (en) | 2000-09-26 | 2002-04-30 | The Procter & Gamble Company | Benzimidazole urea derivatives, and pharmaceutical compositions and unit dosages thereof |
US6407131B1 (en) | 1997-05-16 | 2002-06-18 | The Procter & Gamble Company | Compounds and method for use thereof in the treatment of cancer or viral infections |
US6407105B1 (en) | 2000-09-26 | 2002-06-18 | The Procter & Gamble Company | Compounds and methods for use thereof in the treatment of cancer or viral infections |
US6423734B1 (en) | 1999-08-13 | 2002-07-23 | The Procter & Gamble Company | Method of preventing cancer |
US6462062B1 (en) | 2000-09-26 | 2002-10-08 | The Procter & Gamble Company | Compounds and methods for use thereof in the treatment of cancer or viral infections |
US6479526B1 (en) | 1995-04-12 | 2002-11-12 | The Procter & Gamble Company | Pharmaceutical composition for inhibiting the growth of viruses and cancers |
US6608096B1 (en) | 2000-09-26 | 2003-08-19 | University Of Arizona Foundation | Compounds and methods for use thereof in the treatment of cancer or viral infections |
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US3023103A (en) * | 1960-08-02 | 1962-02-27 | Gen Aniline & Film Corp | Antifoggants and stabilizers for photographic silver halide emulsions |
US3137578A (en) * | 1962-02-07 | 1964-06-16 | Eastman Kodak Co | Photographic emulsions containing 2-heterocyclic benzimidazole antifoggants |
US3255202A (en) * | 1963-08-23 | 1966-06-07 | Union Carbide Corp | Process for the preparation of 2-(acylamidoalkyl)benzimidazoles |
US3271154A (en) * | 1961-11-30 | 1966-09-06 | Gen Aniline & Film Corp | Antifogging and stabilizing agents for photography |
-
1964
- 1964-07-20 US US383963A patent/US3499761A/en not_active Expired - Lifetime
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- 1965-07-20 BE BE667158A patent/BE667158A/xx unknown
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
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US3023103A (en) * | 1960-08-02 | 1962-02-27 | Gen Aniline & Film Corp | Antifoggants and stabilizers for photographic silver halide emulsions |
US3271154A (en) * | 1961-11-30 | 1966-09-06 | Gen Aniline & Film Corp | Antifogging and stabilizing agents for photography |
US3137578A (en) * | 1962-02-07 | 1964-06-16 | Eastman Kodak Co | Photographic emulsions containing 2-heterocyclic benzimidazole antifoggants |
US3255202A (en) * | 1963-08-23 | 1966-06-07 | Union Carbide Corp | Process for the preparation of 2-(acylamidoalkyl)benzimidazoles |
Cited By (38)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3655391A (en) * | 1969-05-16 | 1972-04-11 | Paoli Merli | Azodicarbonamide fog inhibitors |
US3982947A (en) * | 1974-03-14 | 1976-09-28 | Agfa-Gevaert, N.V. | Fog-inhibitors for silver halide photography silver halide photographic material containing an iodo benzene compound as antifoggant |
US4131467A (en) * | 1977-11-23 | 1978-12-26 | E. I. Du Pont De Nemours And Company | 4,7-Dihydroxybenzimidazole hydrobromide as antifogger |
US4572892A (en) * | 1984-05-21 | 1986-02-25 | Eastman Kodak Company | Direct positive photographic elements with incorporated maximum density enhancing antifoggants |
US6479526B1 (en) | 1995-04-12 | 2002-11-12 | The Procter & Gamble Company | Pharmaceutical composition for inhibiting the growth of viruses and cancers |
US6653335B2 (en) | 1995-04-12 | 2003-11-25 | University Of Arizona Foundationa | Pharmaceutical composition for inhibiting the growth of viruses and cancers |
US6362207B1 (en) | 1995-04-12 | 2002-03-26 | The Procter & Gamble Company | Methods of treating viral infections with benzimidazoles |
US6265427B1 (en) | 1995-06-07 | 2001-07-24 | The Proctor & Gamble Company | Pharmaceutical composition for the method of treating leukemia |
US6552059B2 (en) | 1995-06-07 | 2003-04-22 | University Of Arizona Foundation | Pharmaceutical composition for and method of treating leukemia |
US6271217B1 (en) | 1997-01-28 | 2001-08-07 | The Procter & Gamble Company | Method of treating cancer with a benzimidazole and a chemotherapeutic agent |
US6329355B1 (en) | 1997-01-28 | 2001-12-11 | The Procter & Gamble Company | Method for inhibiting the growth of cancers |
US6407131B1 (en) | 1997-05-16 | 2002-06-18 | The Procter & Gamble Company | Compounds and method for use thereof in the treatment of cancer or viral infections |
US6506783B1 (en) | 1997-05-16 | 2003-01-14 | The Procter & Gamble Company | Cancer treatments and pharmaceutical compositions therefor |
US20050192328A1 (en) * | 1997-05-16 | 2005-09-01 | Uaf Technologies And Research, Llc | Compounds and methods for use thereof in the treatment of viral infections |
US6420411B1 (en) | 1997-05-16 | 2002-07-16 | The Procter & Gamble Company | Compounds and methods for use thereof in the treatment of cancer or viral infections |
US6423735B1 (en) | 1997-05-16 | 2002-07-23 | The Procter & Gamble Company | Compounds and methods for use thereof in the treatment of cancer or viral infections |
US6864275B1 (en) | 1997-05-16 | 2005-03-08 | Uaf Technologies And Research, Llc | Compounds and methods for use thereof in the treatment of cancer |
US6423736B1 (en) | 1997-05-16 | 2002-07-23 | The Proctor & Gamble Company | Compounds and methods for use thereof in the treatment of cancer or viral infections |
US6900235B1 (en) | 1997-05-16 | 2005-05-31 | Uaf Technologies And Research, Llc | Benzimidazole compounds, and pharmaceutical compositions and unit dosages thereof |
US20050288349A1 (en) * | 1997-05-16 | 2005-12-29 | Uaf Technologies And Research, Llc | Cancer treatments and pharmaceutical compositions therefor |
US6482843B1 (en) | 1997-05-16 | 2002-11-19 | The Procter & Gamble Company | Compounds and methods for use thereof in the treatment of cancer or viral infections |
US6710065B1 (en) | 1997-05-16 | 2004-03-23 | Uaf Technologies And Research, Llc | Compounds and methods for use thereof in the treatment of cancer |
US6984654B2 (en) | 1997-05-16 | 2006-01-10 | Uaf Technologies And Research, Llc | Cancer treatments and pharmaceutical compositions therefor |
US20050119236A1 (en) * | 1997-05-16 | 2005-06-02 | University Of Arizona Foundation | Cancer treatments and pharmaceutical compositions therefor |
US6245789B1 (en) | 1998-05-19 | 2001-06-12 | The Procter & Gamble Company | HIV and viral treatment |
US6906091B2 (en) | 1999-08-13 | 2005-06-14 | Uaf Technologies And Research, Llc | Method of cancer treatment |
US6423734B1 (en) | 1999-08-13 | 2002-07-23 | The Procter & Gamble Company | Method of preventing cancer |
WO2001083457A3 (en) * | 2000-04-28 | 2002-03-21 | Procter & Gamble | Benzimidazole-2-carbamates and their use in cancer treatment |
WO2001083457A2 (en) * | 2000-04-28 | 2001-11-08 | The Procter & Gamble Company | Benzimidazole-2-carbamates and their use in cancer treatment |
US6720349B2 (en) | 2000-09-26 | 2004-04-13 | Uaf Technologies And Research, Llc | Compounds for use in the treatment of cancer or viral infections |
US20040029942A1 (en) * | 2000-09-26 | 2004-02-12 | University Of Arizona Foundation | Compounds and methods for use thereof in the treatment of viral infections |
US6608096B1 (en) | 2000-09-26 | 2003-08-19 | University Of Arizona Foundation | Compounds and methods for use thereof in the treatment of cancer or viral infections |
US20030100592A1 (en) * | 2000-09-26 | 2003-05-29 | University Of Arizona Foundation | Compounds and methods for use thereof in the treatment of viral infections |
US6462062B1 (en) | 2000-09-26 | 2002-10-08 | The Procter & Gamble Company | Compounds and methods for use thereof in the treatment of cancer or viral infections |
US6916836B2 (en) | 2000-09-26 | 2005-07-12 | Uaf Technologies And Research, Llc | Compounds and methods for use thereof in the treatment of viral infections |
US6930121B2 (en) | 2000-09-26 | 2005-08-16 | Uaf Technologies And Research, Llc | Compounds and methods for use thereof in the treatment of viral infections |
US6407105B1 (en) | 2000-09-26 | 2002-06-18 | The Procter & Gamble Company | Compounds and methods for use thereof in the treatment of cancer or viral infections |
US6380232B1 (en) | 2000-09-26 | 2002-04-30 | The Procter & Gamble Company | Benzimidazole urea derivatives, and pharmaceutical compositions and unit dosages thereof |
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