US2706687A - Preventing formation of prussian blue stain in color developed photographic prints - Google Patents
Preventing formation of prussian blue stain in color developed photographic prints Download PDFInfo
- Publication number
- US2706687A US2706687A US369238A US36923853A US2706687A US 2706687 A US2706687 A US 2706687A US 369238 A US369238 A US 369238A US 36923853 A US36923853 A US 36923853A US 2706687 A US2706687 A US 2706687A
- Authority
- US
- United States
- Prior art keywords
- fixing
- prussian blue
- bath
- layer
- color
- 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
- 230000015572 biosynthetic process Effects 0.000 title claims description 13
- DCYOBGZUOMKFPA-UHFFFAOYSA-N iron(2+);iron(3+);octadecacyanide Chemical compound [Fe+2].[Fe+2].[Fe+2].[Fe+3].[Fe+3].[Fe+3].[Fe+3].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-] DCYOBGZUOMKFPA-UHFFFAOYSA-N 0.000 title claims description 9
- 229960003351 prussian blue Drugs 0.000 title description 5
- 239000013225 prussian blue Substances 0.000 title description 5
- 239000007844 bleaching agent Substances 0.000 claims description 15
- 229910052709 silver Inorganic materials 0.000 claims description 15
- 239000004332 silver Substances 0.000 claims description 15
- -1 SILVER HALIDE Chemical class 0.000 claims description 14
- 239000000839 emulsion Substances 0.000 claims description 14
- 238000000034 method Methods 0.000 claims description 14
- YAGKRVSRTSUGEY-UHFFFAOYSA-N ferricyanide Chemical compound [Fe+3].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-].N#[C-] YAGKRVSRTSUGEY-UHFFFAOYSA-N 0.000 claims description 13
- 150000003839 salts Chemical class 0.000 claims description 8
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims description 7
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 7
- 229910052793 cadmium Inorganic materials 0.000 claims description 7
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 claims description 7
- 239000003795 chemical substances by application Substances 0.000 claims description 7
- 229910052748 manganese Inorganic materials 0.000 claims description 7
- 239000011572 manganese Substances 0.000 claims description 7
- 229910052725 zinc Inorganic materials 0.000 claims description 7
- 239000011701 zinc Substances 0.000 claims description 7
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 6
- 238000004061 bleaching Methods 0.000 claims description 4
- 239000000155 melt Substances 0.000 claims 1
- 239000000243 solution Substances 0.000 description 14
- 239000002253 acid Substances 0.000 description 9
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- 239000000203 mixture Substances 0.000 description 8
- NWONKYPBYAMBJT-UHFFFAOYSA-L zinc sulfate Chemical compound [Zn+2].[O-]S([O-])(=O)=O NWONKYPBYAMBJT-UHFFFAOYSA-L 0.000 description 7
- 229960001763 zinc sulfate Drugs 0.000 description 7
- 229910000368 zinc sulfate Inorganic materials 0.000 description 7
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 6
- 229910052783 alkali metal Inorganic materials 0.000 description 4
- 229910052742 iron Inorganic materials 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 235000010265 sodium sulphite Nutrition 0.000 description 4
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 4
- 235000019345 sodium thiosulphate Nutrition 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 239000002244 precipitate Substances 0.000 description 3
- DHCDFWKWKRSZHF-UHFFFAOYSA-N sulfurothioic S-acid Chemical compound OS(O)(=O)=S DHCDFWKWKRSZHF-UHFFFAOYSA-N 0.000 description 3
- 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
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- PXRKCOCTEMYUEG-UHFFFAOYSA-N 5-aminoisoindole-1,3-dione Chemical compound NC1=CC=C2C(=O)NC(=O)C2=C1 PXRKCOCTEMYUEG-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 235000011054 acetic acid Nutrition 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- XYXNTHIYBIDHGM-UHFFFAOYSA-N ammonium thiosulfate Chemical compound [NH4+].[NH4+].[O-]S([O-])(=O)=S XYXNTHIYBIDHGM-UHFFFAOYSA-N 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 1
- 239000004327 boric acid Substances 0.000 description 1
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Substances OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- BHZRJJOHZFYXTO-UHFFFAOYSA-L potassium sulfite Chemical compound [K+].[K+].[O-]S([O-])=O BHZRJJOHZFYXTO-UHFFFAOYSA-L 0.000 description 1
- 235000019252 potassium sulphite Nutrition 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000002035 prolonged effect Effects 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
- G03C5/38—Fixing; Developing-fixing; Hardening-fixing
Definitions
- This invention relates to color photography and particularly to a method and means for preventing the formation of a Prussian blue stain in photographic prints which have been color developed and treated with a ferricyanide bleach.
- a certain amount of the ferricyanide of the bleach is retained in the emulsion or in the paper stock in the case of emulsions coated on a paper support and during or after processing a blue stain may appear in the emulsion or on the support. This stain may occur during the processing cycle, particularly if the paper subsequently passes through any acid solution or it may become evident upon prolonged keeping under adverse conditions of heat and humidity.
- One source of iron in the processing solutions is the piping and processing tanks through which the solutions pass.
- a source of iron is also the wash water or water used to make up the various solutions.
- a further object is to provide a fixing composition which will serve to prevent the formation of a Prussian blue stain in color developed prints.
- the usual fixing bath contains a thiosulfate such as sodium, potassium or ammonium thiosulfate, an alkali metal sulfite such as sodium or potassium sulfite, acid such as acetic, citric or boric acid, and may contain other ingredients such as hardening agents, etc.
- a typical fixing bath would have the following composition:
- the amount of zinc sulfate used in the acid fixing bath may vary from 5 to 10 or more grams per liter but usually these amounts are found to be adequate.
- Our agents may also be used in dry packaged photographic compositions adapted to form an acid fixing bath upon mixing with water.
- Such compositions may contain about 50 parts of sodium thiosulfate, about 3 parts of desiccated sodium sulfite and about 1 part of zinc sulfate.
- Other agents such as hardening agents may also be present.
- the method of preventing the formation of ferric ferrocyanide in a color-developed and fixed silver halide emulsion layer which has been subjected to a ferricyanide bleach bath which comprises fixing said layer after development and bleaching with said bleach bath, with a solution containing a fixing agent for silver halide, in the presence of a water-soluble salt of a metal selected from the class consisting of zinc, cadmium and manganese.
- the method of preventing the formation of ferric ferrocyanide in a color-developed and fixed silver halide emulsion layer which has been subjected to a ferricyanide bleach bath which comprises fixing said layer after development and bleaching with said bleach bath, with a solution of thiosulfate, an alkali metal sulfite and an acid, in the presence of a water-soluble salt of a metal selected from the class consisting of zinc, cadmium and manganese.
- a fixing composition adapted to fix a developed silver halide emulsion layer and prevent formation of colored ferrocyanides after treatment of the layer with a ferricyanide bleach comprising a thiosulfate, an alkali metal sulfite, an acid, and a water-soluble salt of a metal selected from the class consisting of zinc, cadmium and manganese.
- a fixing composition adapted to fix a developed silver halide emulsion layer and prevent formation of colored ferrocyanides after treatment of the layer with a ferricyanide bleach, comprising an alkali metal thiosulfate, an alkli metal sulfite, acetic acid, and zinc sulfate.
- a fixing composition adapted to fix a developed silver halide emulsion layer and prevent formation of 10 colored ferrocyanides after treatment of the layer with a f erricyanide bleach, comprising sodium thiosulfate, SOdlUITl sulfite, acetlc acid and zinc sulfate.
- a dry packaged photographic composition adapted to form an acid fixing bath suitable for fixing a colordeveloped photographic layer and preventing the formation of colored ferrocyanides in said layer after treatment of said layer with a ferricyanide bleach bath, comprising approximately 1 part of zinc sulfate, approximately 3 parts of sodium sulfite and approximately 50 parts of sodium thiosulfate.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Silver Salt Photography Or Processing Solution Therefor (AREA)
Description
2,706,687 Patented Apr. 19, 1955 PREVENTING FORMATION OF PRUSSIAN BLUE STANIN sIN COLOR DEVELOPED PHOTOGRAPHIC PR T Herbert L. Rees and Robert B. Henrickson, Rochester,
N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application July 20, 1953, Serial No. 369,238
7 Claims. (CI. 95-88) This invention relates to color photography and particularly to a method and means for preventing the formation of a Prussian blue stain in photographic prints which have been color developed and treated with a ferricyanide bleach.
It is well known that in certain processes of color forming photographic development, in which colored images are formed upon development by the action of the oxidation product of a primary aromatic developing agent upon a color forming compound or coupler, it is sometimes desirable to remove the developed silver image without destroying the residual silver halide or the dye image formed in the layer. A solution of a ferricyanide such as an alkaline solution of potassium ferricyanide is frequently used for this purpose. This solution converts the silver image to silver ferrocyanide, which is then removed with a solvent such as hypo. A certain amount of the ferricyanide of the bleach is retained in the emulsion or in the paper stock in the case of emulsions coated on a paper support and during or after processing a blue stain may appear in the emulsion or on the support. This stain may occur during the processing cycle, particularly if the paper subsequently passes through any acid solution or it may become evident upon prolonged keeping under adverse conditions of heat and humidity.
This blue stain is evidently Prussion blue formed in the following way. Ferricyanide from the bleach bath which is retained in the emulsion or support is converted to ferrocyanide during the subsequent hypo treatment, according to the following scheme:
Any iron which may be present in subsequent solutions converts the ferrocyanide to Prussion blue according to the following well known reaction:
One source of iron in the processing solutions is the piping and processing tanks through which the solutions pass. A source of iron is also the wash water or water used to make up the various solutions.
It is therefore an object of the present invention to provide a method and means for preventing the formation of this undesirable Prussian blue stain in color developed photographic prints. A further object is to provide a fixing composition which will serve to prevent the formation of a Prussian blue stain in color developed prints. Other objects will appear from the following description of our invention.
These objects are accomplished by incorporating in the fixing bath or in a separate bath used prior to fixing, a water-soluble salt of zinc, cadmium or manganese.
Processes of color photography in which color developed images are formed in photographic emulsion layers are described in Mannes, Godowsky and Wilder U. S. Patent 2,252,718, granted August 19, 1941, and in Jelley and Vittum U. S. Patent 2,322,027, granted June 15, 1943, Example 7. In the former patent a reversal process using couplers incorporated in the developing solutions is described and in the latter patent a negative process using couplers incorporated in the emulsion layers is described. Couplers may also be incorporated in the processing solutions in a negativepositive process and couplers may be incorporated in the emulsion layer or layers in a reversal process. In any of these processes the silver images may be converted to silver ferrocyanide by treatment with a ferricyanide bath prior to fixing with hypo or other solvent.
In color development processes of these types, we propose to incorporate in the hypo solution or in a solution used after the ferricyanide bath but prior to fixing with hypo, a soluble salt of zinc, cadmium or manganese. Zinc sulfate, for example, may be incorporated in the acid fixing bath and this compound reacts with the ferrocyanide in the paper to form insoluble white zinc ferrocyanide according to the following scheme:
NatFeCys +ZnSO4- ZnzFeCys This reaction proceeds to completion and removes the ferrocyanide so that none is left to form Prussian blue with the iron. Formation of a white precipitate is, of course, necessary since any colored precipitate would show in the finished print. Other salts which give a white precipitate with ferrocyanide such as soluble salts of cadmium and manganese can also be used.
The usual fixing bath contains a thiosulfate such as sodium, potassium or ammonium thiosulfate, an alkali metal sulfite such as sodium or potassium sulfite, acid such as acetic, citric or boric acid, and may contain other ingredients such as hardening agents, etc. A typical fixing bath would have the following composition:
Water to 1 liter.
The amount of zinc sulfate used in the acid fixing bath may vary from 5 to 10 or more grams per liter but usually these amounts are found to be adequate.
Our agents may also be used in dry packaged photographic compositions adapted to form an acid fixing bath upon mixing with water. Such compositions may contain about 50 parts of sodium thiosulfate, about 3 parts of desiccated sodium sulfite and about 1 part of zinc sulfate. Other agents such as hardening agents may also be present.
It will be understood that the examples and modifications included herein are illustrative only and that the invention is to be taken as limited only by the scope of the appended claims.
We claim:
1. The method of preventing the formation of ferric ferrocyanide in a color-developed and fixed silver halide emulsion layer which has been subjected to a ferricyanide bleach bath, which comprises fixing said layer after development and bleaching with said bleach bath, with a solution containing a fixing agent for silver halide, in the presence of a water-soluble salt of a metal selected from the class consisting of zinc, cadmium and manganese.
2. The method of preventing the formation of ferric ferrocyanide in a color-developed and fixed silver halide emulsion layer which has been subjected to a ferricyanide bleach bath, which comprises fixing said layer after development and bleaching with said bleach bath, with a solution of thiosulfate, an alkali metal sulfite and an acid, in the presence of a water-soluble salt of a metal selected from the class consisting of zinc, cadmium and manganese.
3. The method of preventing the formation of ferric ferrocyanide in a color-developed and fixed silver halide emulsion layer which has been subjected to a ferricyanide bleach bath, which comprises fixing said layer after development and bleaching with said bleach bath, with a solution of sodium thiosulfate, sodium sulfite, acetic acid and zinc sulfate. 7
4. A fixing composition adapted to fix a developed silver halide emulsion layer and prevent formation of colored ferrocyanides after treatment of the layer with a ferricyanide bleach, comprising a thiosulfate, an alkali metal sulfite, an acid, and a water-soluble salt of a metal selected from the class consisting of zinc, cadmium and manganese.
5. A fixing composition adapted to fix a developed silver halide emulsion layer and prevent formation of colored ferrocyanides after treatment of the layer with a ferricyanide bleach, comprising an alkali metal thiosulfate, an alkli metal sulfite, acetic acid, and zinc sulfate.
6. A fixing composition adapted to fix a developed silver halide emulsion layer and prevent formation of 10 colored ferrocyanides after treatment of the layer with a f erricyanide bleach, comprising sodium thiosulfate, SOdlUITl sulfite, acetlc acid and zinc sulfate.
7. A dry packaged photographic composition adapted to form an acid fixing bath suitable for fixing a colordeveloped photographic layer and preventing the formation of colored ferrocyanides in said layer after treatment of said layer with a ferricyanide bleach bath, comprising approximately 1 part of zinc sulfate, approximately 3 parts of sodium sulfite and approximately 50 parts of sodium thiosulfate.
References Cited in the file of this patent UNITED STATES PATENTS 1,624,172 Levy Apr. 12, 1927
Claims (1)
1. THE METHOD OF PREVENTING THE FORMATION OF FERRIC FERROCYANIDE IN A COLOR-DEVELOPED AND FIXED SILVER HALIDE EMULSION LAYER WHICH HAS BEEN SUBJECTED TO A FERRICYANIDE BLEACH BATH, WHICH COMPRISES FIXING SAID LAYER AFTER DEVELOPMENT AND BLEACHING WITH SAID BLEACH BATH, WITH A SOLUTION CONTANING A FIXING AGENT FOR SILVER HAL IDE, IN THE PRESENCE OF A WATER-SOLUBLE SALT OF A MELT SELECTED FROM THE CLASS CONSISTING OF ZINC, CADMIUM AND MANGANESE.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US369238A US2706687A (en) | 1953-07-20 | 1953-07-20 | Preventing formation of prussian blue stain in color developed photographic prints |
| FR1103688D FR1103688A (en) | 1953-07-20 | 1954-07-05 | Improvement in color photography |
| GB21011/54A GB751186A (en) | 1953-07-20 | 1954-07-19 | Improvements in processes of colour photography and compositions therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US369238A US2706687A (en) | 1953-07-20 | 1953-07-20 | Preventing formation of prussian blue stain in color developed photographic prints |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2706687A true US2706687A (en) | 1955-04-19 |
Family
ID=23454678
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US369238A Expired - Lifetime US2706687A (en) | 1953-07-20 | 1953-07-20 | Preventing formation of prussian blue stain in color developed photographic prints |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US2706687A (en) |
| FR (1) | FR1103688A (en) |
| GB (1) | GB751186A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2788274A (en) * | 1954-04-14 | 1957-04-09 | Gen Aniline & Film Corp | Process of inhibiting the discoloration of photographic color images |
| US2913338A (en) * | 1957-01-10 | 1959-11-17 | Gen Aniline & Film Corp | Prevention of cyan dye fading in color developed prints and films |
| US3035914A (en) * | 1957-01-10 | 1962-05-22 | Gen Aniline & Film Corp | Prevention of cyan dye fading in color developed prints and films |
| US3239340A (en) * | 1963-02-18 | 1966-03-08 | Fuji Photo Film Co Ltd | Method for stabilizing developed photosensitive materials |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1624172A (en) * | 1927-04-12 | of los angeles |
-
1953
- 1953-07-20 US US369238A patent/US2706687A/en not_active Expired - Lifetime
-
1954
- 1954-07-05 FR FR1103688D patent/FR1103688A/en not_active Expired
- 1954-07-19 GB GB21011/54A patent/GB751186A/en not_active Expired
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1624172A (en) * | 1927-04-12 | of los angeles |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2788274A (en) * | 1954-04-14 | 1957-04-09 | Gen Aniline & Film Corp | Process of inhibiting the discoloration of photographic color images |
| US2913338A (en) * | 1957-01-10 | 1959-11-17 | Gen Aniline & Film Corp | Prevention of cyan dye fading in color developed prints and films |
| US3035914A (en) * | 1957-01-10 | 1962-05-22 | Gen Aniline & Film Corp | Prevention of cyan dye fading in color developed prints and films |
| US3239340A (en) * | 1963-02-18 | 1966-03-08 | Fuji Photo Film Co Ltd | Method for stabilizing developed photosensitive materials |
Also Published As
| Publication number | Publication date |
|---|---|
| GB751186A (en) | 1956-06-27 |
| FR1103688A (en) | 1955-11-04 |
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