US3512981A - Stable photographic developers containing ascorbic acid - Google Patents
Stable photographic developers containing ascorbic acid Download PDFInfo
- Publication number
- US3512981A US3512981A US702797A US3512981DA US3512981A US 3512981 A US3512981 A US 3512981A US 702797 A US702797 A US 702797A US 3512981D A US3512981D A US 3512981DA US 3512981 A US3512981 A US 3512981A
- Authority
- US
- United States
- Prior art keywords
- sulfite
- solution
- ascorbic acid
- developing
- developer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 title description 37
- 235000010323 ascorbic acid Nutrition 0.000 title description 20
- 229960005070 ascorbic acid Drugs 0.000 title description 18
- 239000011668 ascorbic acid Substances 0.000 title description 16
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 53
- 239000000243 solution Substances 0.000 description 49
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 29
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 24
- DETXZQGDWUJKMO-UHFFFAOYSA-N 2-hydroxymethanesulfonic acid Chemical compound OCS(O)(=O)=O DETXZQGDWUJKMO-UHFFFAOYSA-N 0.000 description 14
- 239000003795 chemical substances by application Substances 0.000 description 13
- 239000000839 emulsion Substances 0.000 description 13
- 235000010265 sodium sulphite Nutrition 0.000 description 12
- 239000000203 mixture Substances 0.000 description 10
- -1 silver halide Chemical class 0.000 description 10
- 229910052709 silver Inorganic materials 0.000 description 9
- 239000004332 silver Substances 0.000 description 9
- 150000000996 L-ascorbic acids Chemical class 0.000 description 8
- GGNQRNBDZQJCCN-UHFFFAOYSA-N benzene-1,2,4-triol Chemical compound OC1=CC=C(O)C(O)=C1 GGNQRNBDZQJCCN-UHFFFAOYSA-N 0.000 description 8
- IOLCXVTUBQKXJR-UHFFFAOYSA-M potassium bromide Chemical compound [K+].[Br-] IOLCXVTUBQKXJR-UHFFFAOYSA-M 0.000 description 8
- 238000007254 oxidation reaction Methods 0.000 description 7
- 230000003647 oxidation Effects 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 239000000470 constituent Substances 0.000 description 4
- 238000011161 development Methods 0.000 description 4
- MQRJBSHKWOFOGF-UHFFFAOYSA-L disodium;carbonate;hydrate Chemical compound O.[Na+].[Na+].[O-]C([O-])=O MQRJBSHKWOFOGF-UHFFFAOYSA-L 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 230000002195 synergetic effect Effects 0.000 description 4
- 239000012224 working solution Substances 0.000 description 4
- 150000001447 alkali salts Chemical class 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 3
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 3
- 230000001965 increasing effect Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- CNHDIAIOKMXOLK-UHFFFAOYSA-N toluquinol Chemical compound CC1=CC(O)=CC=C1O CNHDIAIOKMXOLK-UHFFFAOYSA-N 0.000 description 3
- GPASWZHHWPVSRG-UHFFFAOYSA-N 2,5-dimethylbenzene-1,4-diol Chemical compound CC1=CC(O)=C(C)C=C1O GPASWZHHWPVSRG-UHFFFAOYSA-N 0.000 description 2
- PLIKAWJENQZMHA-UHFFFAOYSA-N 4-aminophenol Chemical compound NC1=CC=C(O)C=C1 PLIKAWJENQZMHA-UHFFFAOYSA-N 0.000 description 2
- PAYRUJLWNCNPSJ-UHFFFAOYSA-N Aniline Chemical compound NC1=CC=CC=C1 PAYRUJLWNCNPSJ-UHFFFAOYSA-N 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound 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 2
- 239000002211 L-ascorbic acid Substances 0.000 description 2
- 235000000069 L-ascorbic acid Nutrition 0.000 description 2
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 239000000872 buffer Substances 0.000 description 2
- DXRFSTNITSDOKK-UHFFFAOYSA-N formaldehyde;sulfurous acid Chemical class O=C.OS(O)=O DXRFSTNITSDOKK-UHFFFAOYSA-N 0.000 description 2
- 208000015181 infectious disease Diseases 0.000 description 2
- 230000002458 infectious effect Effects 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000033458 reproduction Effects 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- UOULCEYHQNCFFH-UHFFFAOYSA-M sodium;hydroxymethanesulfonate Chemical compound [Na+].OCS([O-])(=O)=O UOULCEYHQNCFFH-UHFFFAOYSA-M 0.000 description 2
- ILBBPBRROBHKQL-SAMGZKJBSA-N (2s)-3,4-dihydroxy-2-[(1r,2r)-1,2,3-trihydroxypropyl]-2h-furan-5-one Chemical compound OC[C@@H](O)[C@@H](O)[C@@H]1OC(=O)C(O)=C1O ILBBPBRROBHKQL-SAMGZKJBSA-N 0.000 description 1
- 150000005208 1,4-dihydroxybenzenes Chemical class 0.000 description 1
- CBCKQZAAMUWICA-UHFFFAOYSA-N 1,4-phenylenediamine Chemical compound NC1=CC=C(N)C=C1 CBCKQZAAMUWICA-UHFFFAOYSA-N 0.000 description 1
- YZDIUKPBJDYTOM-UHFFFAOYSA-N 2,5-diethylbenzene-1,4-diol Chemical compound CCC1=CC(O)=C(CC)C=C1O YZDIUKPBJDYTOM-UHFFFAOYSA-N 0.000 description 1
- ZFIQGRISGKSVAG-UHFFFAOYSA-N 4-methylaminophenol Chemical compound CNC1=CC=C(O)C=C1 ZFIQGRISGKSVAG-UHFFFAOYSA-N 0.000 description 1
- ZZZCUOFIHGPKAK-UHFFFAOYSA-N D-erythro-ascorbic acid Natural products OCC1OC(=O)C(O)=C1O ZZZCUOFIHGPKAK-UHFFFAOYSA-N 0.000 description 1
- 235000014276 Diplazium esculentum Nutrition 0.000 description 1
- 244000108321 Diplazium esculentum Species 0.000 description 1
- 239000004260 Potassium ascorbate Substances 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229930003268 Vitamin C Natural products 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000005273 aeration Methods 0.000 description 1
- 230000001174 ascending effect Effects 0.000 description 1
- 125000003289 ascorbyl group Chemical group [H]O[C@@]([H])(C([H])([H])O*)[C@@]1([H])OC(=O)C(O*)=C1O* 0.000 description 1
- UREVLELSVZQJTM-UHFFFAOYSA-N benzene-1,4-diol;formaldehyde Chemical compound O=C.OC1=CC=C(O)C=C1 UREVLELSVZQJTM-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 210000003127 knee Anatomy 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229960003742 phenol Drugs 0.000 description 1
- 229920000136 polysorbate Polymers 0.000 description 1
- 235000019275 potassium ascorbate Nutrition 0.000 description 1
- 229940017794 potassium ascorbate Drugs 0.000 description 1
- CONVKSGEGAVTMB-RXSVEWSESA-M potassium-L-ascorbate Chemical compound [K+].OC[C@H](O)[C@H]1OC(=O)C(O)=C1[O-] CONVKSGEGAVTMB-RXSVEWSESA-M 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 235000010378 sodium ascorbate Nutrition 0.000 description 1
- PPASLZSBLFJQEF-RKJRWTFHSA-M sodium ascorbate Substances [Na+].OC[C@@H](O)[C@H]1OC(=O)C(O)=C1[O-] PPASLZSBLFJQEF-RKJRWTFHSA-M 0.000 description 1
- 229960005055 sodium ascorbate Drugs 0.000 description 1
- 229910052979 sodium sulfide Inorganic materials 0.000 description 1
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 description 1
- 235000019154 vitamin C Nutrition 0.000 description 1
- 239000011718 vitamin C Substances 0.000 description 1
Classifications
-
- 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
- This invention relates in general to photographic developers, and more particularly to developers used to develop latent images present in those photosensitive silver halide photographic films employed in the graphic arts for making line or half-tone images and other films used for producing photographic reproductions having very high contrast and image sharpness. These developers are frequently referred to as lith type developers.
- the preferred photographic developer for producing high contrast and image sharpness for the graphic arts is a solution of a p-dihydroxybenzene developing agent.
- Normally hydroquinone is utilized as the developing agent for photographic silver halide emulsions.
- Working solutions containing such developing agents are very susceptible to aerial oxidation and consequently possess a very short tray life. After a few hours of exposure to ordinary atmospheric conditions, even without actual use, the response of the developer is greatly impaired and the solutions become generally ineffective. This loss of elfectiveness results in loss of density range and dot quality, and contrast is reduced or lost in the images being produced.
- this loss of effectiveness of developing solutions is extremely costly whenever large volumes of developer are being utilized as in automatic processing machines.
- One technique for reducing costs of developer in automatic processing machines is to utilize developer replenishers, these being commonly stored in large quantities within the processing machine, however, these replenishers are similarly subject to aerial oxidation and will accordingly become ineffective after limited periods of exposure.
- an improved photographic developer which employs a combination of a p-dihydroxybenzene together with a combination of a water soluble sulfite and ascorbic acid.
- the p-dihydroxybenzene component is normally hydroquinone, the Water soluble sulfite normally being sodium sulfite, the ascorbic acid normally being either ascorbic acid or the sodium or other alkali salts of ascorbic acid as well 3,512,981 Patented May 19, 1970 as certain stereioisornetric forms of ascorbic acid.
- the ascorbic acids have the following general structure:
- R represents a hydroxy group when n represents a positive integer from 1 to 4 and R represents a hydrogen atom when n represents a positive integer of from 2 to 4.
- ascorbic acid including sodium or potassium ascorbate, 1 erythroascorbic acid, and d glucoascorbic acid have been found effective in this combination.
- the developing solutions employing a p-dihydroxybenzene such as hydroquinone a synergistic effect is experienced when both sulfite and ascorbic acid are present, this synergistic effect being manifested in the preparation of a highly stable solution capable of preparing reproductions having sharp contrast with sharpness of image.
- 'It is a further object of the present invention to provide a photographic developer replenisher that has an extended tray and shelf life.
- an exposed photographic silver halide emulsion is processed or developed in a solution of a p-dihydroxybenzene developing agent, preferably hydroquinone, the solution containing ascorbic acid or its derivatives in an amount preferably in the range of about .5 to 10 grams to liter of solution (depending upon the degree of extended tray life desired) and between about V2 gram and 5 grams of a dissociated sulfite per liter of solution.
- the term dissociated is employed herein in a comprehensive sense, and accordingly is intended to include ionized, as well. It has been found that the synergestic effect as pointed out hereina'bove is diminished when less than about A.
- This phenomenon defined as peppering may be described as the formation of one or more randomly arranged generally round high or low density spots occurring in areas of reciprocal developed density. While the phenomenon is not entirely understood, it appears to be the result of an accelerated development of certain areas of the photosensitive silver halide emulsion film which areas have received only a minimal or marginal amount of exposure, and which exposure is below that lower threshold limit necessary to obtain a maximum or high density. This phenomena occurs more frequently with those photosensitive silver halide emulsions which are normally regarded as having the highest ability to render high contrast over prolonged developing time ranges.
- the developer of the present invention is capable of providing rapid developing of latent images present in photosensitive silver halide emulsion films, this rapid development being possible without the introduction of areas of peppering in the product.
- the sulfite is kept at a level concentration of between about /2 and grams per liter determined as sodium sulfite, and formaldehyde bisulfite complexes are utilized as sulfite buffers to provide a solution having a constant and controllable low sulfite concentration within the desired range.
- This range provides a working solution having a sulfite concentration of from between about 0.004 molar and 0.04 molar. Solutions with a sulfite concentration of 0.002 molar may be useful in some systems.
- the formaldehyde bisulfite complexes control the sulfite concentration through replenishing of the sulfite consumed during the developing reactions,
- Photographic emulsions designed for producing high contrast images including lith type emulsions are commercially available.
- One such type is available under the designation Kodalith films from Eastman Kodak Company of Rochester, N.Y., various similar types being available commercially from the E. I. du Pont de Nemours Company of Wilmington, Del., as well as others. While these various photographic emulsions have the desired high contrast and dot quality when developed in known high contrast developers, it is of course desirable to increase the useful life of the developer solution by increasing the resistance of the developing solution to aerial oxidation upon exposure to ordinary atmospheric conditions.
- the developing solutions of the present invention contain a p-dihydroxybenzene developing agent such as hydroquinone, although toluhydroquinone, 2,5-dimethylhydroquinone and the like have been found useful.
- p-dihydroxybenzene is intended to include materials such as 1,2,4-trihydroxybenzene and the like.
- aminobenzene developing agents such as for example p-aminophenol, n-methyl-p-aminophenol, p-phenylenediamine, etc. It will be appreciated, of course, that trace quantities in the range of, for example, less, th n 0.05 gram per liter of these developing agents may be present in some solutions, greater quantities having been found to reduce contrast.
- the ascorbic acids and the isomers and their derivatives, which are used in the developer solution are acids of the structural formula set forth hereinabove. Ascorbic acids are commonly referred to as Vitamin C and their preparation, sources and derivatives are described in the Encyclopedia of Chemical Technology, vol. 2, pages 150 to 163, published by the Interscience Encyclopedia, Inc. These ascorbic acids and the isomers and their derivatives are most readily obtained in pharmaceutical grade, however, pharmaceutical grade is not necessary. Good results are achieved Whenever developer solutions generally free of impurities are employed which provide extended tray life and shelf life of the working solutions of the present invention. The inclusion of ascorbic acid in the sulfite containing solution has been found to result in very little, if any, loss in speed of developing, and no loss in contrast (gamma) even after extended times of exposure of the developer solution to atmospheric air.
- the second and third strips of the same exposed film were processed under identical conditions in the same developer solution, the second strip being processed after 4 hours and the third strip being processed after 6 hours.
- the degradation of the relative speed and contrast range is shown in the sensitometric results of the second and third strips which were processed after 4 and 6 hours, respectively.
- This composition utilized a multi-functional hydroxybenzene as a substituted hydroquinone, this being 1,2,4-trihydroxybenzene. Good results were achieved with this composition.
- EXAMPLE E A developing solution was prepared having a composition similar to that in Example A, with the exception of toluhydroquinone being substituted for hydroquinone, the quantity remaining at 12 grams per liter. This solution was not as readily balanced as the solution in Example A, however developer activity level was considered satisfactory.
- a stable photographic developer solution consisting of an aqueous solution of:
- an ascorbic acid analogue selected from the group 6 consisting of those certain substances having the structural formula wherein R represents a hydroxy group when n represents a positive integer from 1 to 4 and R represents a hydrogen atom when n represents a positive integer of from 2 to 4, and the alkali salts of said certain substances;
- the photographic developer solution as set forth in claim 2 being particularly characterized in that said l-ascorbic acid is present in said solution in an amount ranging from between about 0.5 gram per liter and 10 grams per liter.
- the photographic developer solution as set forth in claim 1 being particularly characterized in that said dissociated sulfite is derived from the combined presence of an alkali sulfite and formaldehyde bisulfite in said solution.
- the photographic developer solution as set forth in claim 1 being particularly characterized in that said p-dihydroxybenzene developing agent is selected from the group consisting of hydroquinone, toluhydroquinone, 2,5-dimethylhydroquinone, 2,5-diethylhydroquinone, and 1,2,4-trihydroxybenzene.
- a stable photographic developer solution consisting of an aqueous solution of:
- an ascorbic acid analogue selected from the group consisting of those certain substances having the structural formula wherein R represents a hydroxy group when n represents a positive integer from 1 to 4 and R represents a hydrogen atom when n represents a positive integer of from 2 to 4, and the alkali salts of said certain substances;
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Silver Salt Photography Or Processing Solution Therefor (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US70279768A | 1968-02-05 | 1968-02-05 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3512981A true US3512981A (en) | 1970-05-19 |
Family
ID=24822637
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US702797A Expired - Lifetime US3512981A (en) | 1968-02-05 | 1968-02-05 | Stable photographic developers containing ascorbic acid |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US3512981A (en)) |
| BE (1) | BE727894A (en)) |
| DE (1) | DE1772801A1 (en)) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4847339A (en)) * | 1971-10-15 | 1973-07-05 | ||
| US5236816A (en) * | 1992-04-10 | 1993-08-17 | Eastman Kodak Company | Photographic developing solution and use thereof in the high contrast development of nucleated photographic elements |
| US5264323A (en) * | 1992-04-10 | 1993-11-23 | Eastman Kodak Company | Photographic developing solution and use thereof in the high contrast development of nucleated photographic elements |
| US5342741A (en) * | 1992-07-10 | 1994-08-30 | Fuji Photo Film Co., Ltd. | Method of processing silver halide photographic material and composition for processing |
| US5385811A (en) * | 1993-04-27 | 1995-01-31 | Fuji Photo Film Co., Ltd. | Method for processing silver halide photographic materials |
| EP0731382A1 (en) * | 1995-02-21 | 1996-09-11 | Agfa-Gevaert N.V. | Method for processing an exposed photographic silver halide material |
| EP0732619A1 (en) * | 1995-02-21 | 1996-09-18 | Agfa-Gevaert N.V. | Developing method and method for developing an exposed photographic silver halide material |
| US6379877B1 (en) | 1995-02-21 | 2002-04-30 | Agfa-Gevaert | Method for developing an exposed photographic silver halide material |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2415666A (en) * | 1943-07-10 | 1947-02-11 | Eastman Kodak Co | Ascorbic acid in photographic developing solutions |
| US3022168A (en) * | 1958-06-28 | 1962-02-20 | Pharmacia Ab | Photographic developer |
| US3128180A (en) * | 1958-07-02 | 1964-04-07 | Eastman Kodak Co | Hardened high-contrast photographic silver chloride emulsions and method of processing |
-
1968
- 1968-02-05 US US702797A patent/US3512981A/en not_active Expired - Lifetime
- 1968-07-05 DE DE19681772801 patent/DE1772801A1/de active Pending
-
1969
- 1969-02-04 BE BE727894D patent/BE727894A/xx unknown
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2415666A (en) * | 1943-07-10 | 1947-02-11 | Eastman Kodak Co | Ascorbic acid in photographic developing solutions |
| US3022168A (en) * | 1958-06-28 | 1962-02-20 | Pharmacia Ab | Photographic developer |
| US3128180A (en) * | 1958-07-02 | 1964-04-07 | Eastman Kodak Co | Hardened high-contrast photographic silver chloride emulsions and method of processing |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4847339A (en)) * | 1971-10-15 | 1973-07-05 | ||
| US3870479A (en) * | 1971-10-15 | 1975-03-11 | Fuji Photo Film Co Ltd | Lithographic type diffusion transfer developer |
| US5236816A (en) * | 1992-04-10 | 1993-08-17 | Eastman Kodak Company | Photographic developing solution and use thereof in the high contrast development of nucleated photographic elements |
| US5264323A (en) * | 1992-04-10 | 1993-11-23 | Eastman Kodak Company | Photographic developing solution and use thereof in the high contrast development of nucleated photographic elements |
| US5342741A (en) * | 1992-07-10 | 1994-08-30 | Fuji Photo Film Co., Ltd. | Method of processing silver halide photographic material and composition for processing |
| US5385811A (en) * | 1993-04-27 | 1995-01-31 | Fuji Photo Film Co., Ltd. | Method for processing silver halide photographic materials |
| EP0731382A1 (en) * | 1995-02-21 | 1996-09-11 | Agfa-Gevaert N.V. | Method for processing an exposed photographic silver halide material |
| EP0732619A1 (en) * | 1995-02-21 | 1996-09-18 | Agfa-Gevaert N.V. | Developing method and method for developing an exposed photographic silver halide material |
| US6379877B1 (en) | 1995-02-21 | 2002-04-30 | Agfa-Gevaert | Method for developing an exposed photographic silver halide material |
Also Published As
| Publication number | Publication date |
|---|---|
| DE1772801A1 (de) | 1970-03-19 |
| BE727894A (en)) | 1969-07-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3512981A (en) | Stable photographic developers containing ascorbic acid | |
| US3865591A (en) | General purpose developer | |
| US4172728A (en) | High contrast continuous tone developer and process of use | |
| US4046571A (en) | Processing solution for use as photographic developer bath and replenisher therefor | |
| EP0738400B1 (en) | Non-hydroquinone photographic developer composition and processing method | |
| US2415666A (en) | Ascorbic acid in photographic developing solutions | |
| US5738979A (en) | Black-and-white development processing method with replenishment | |
| US3161513A (en) | Photographic developer compositions containing an antistain agent | |
| US2782120A (en) | Combined developer and fixer | |
| US3161514A (en) | Nonstaining photographic developers | |
| US3318701A (en) | Photographic monobaths containing a dl 6-8 dithio-octanoic acid antisludging agent | |
| US3632341A (en) | Photographic developer | |
| US5503966A (en) | Photographic developing compositions and use thereof in the processing of photographic elements | |
| US3615529A (en) | Rapid developing photographic materials containing arginine | |
| US3857710A (en) | High contrast, high capacity monobath processing method and composition for monochrome film | |
| JP3249521B2 (ja) | 写真現像液の安定化 | |
| US2397016A (en) | Combined developer and fixer | |
| US3314789A (en) | Quaternary ammonium salts in silver halide processing solutions | |
| US2887377A (en) | High speed developer | |
| US3819378A (en) | Fine grain high speed photographic processing monobath composition | |
| US2333766A (en) | Photography | |
| US3806344A (en) | Three-component developer photographic processing monobath composition and method | |
| US2782121A (en) | Combined developer and fixer | |
| US3776731A (en) | Developer for photographic negatives used for printing | |
| US2458376A (en) | Photographic developer antioxidants |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: NORTHWESTERN NATIONAL BANK OF MINNEAPOLIS, 7TH STR Free format text: MORTGAGE;ASSIGNOR:PAKO CORPORATION A DE CORP.;REEL/FRAME:004126/0659 Effective date: 19820618 Owner name: PRUDENTIAL INSURANCE COMPANY OF AMERICA THE, P.O. Free format text: MORTGAGE;ASSIGNOR:PAKO CORPORATION A DE CORP.;REEL/FRAME:004126/0659 Effective date: 19820618 Owner name: FIRST NATIONAL BANK OF MINNEAPOLIS, FIRST BANK PLA Free format text: MORTGAGE;ASSIGNOR:PAKO CORPORATION A DE CORP.;REEL/FRAME:004126/0659 Effective date: 19820618 Owner name: CONTINENTAL ILLINOIS NATIONAL BANK AND TRUST COMPA Free format text: MORTGAGE;ASSIGNOR:PAKO CORPORATION A DE CORP.;REEL/FRAME:004126/0659 Effective date: 19820618 |