US1933804A - Regeneration of photographic developers - Google Patents
Regeneration of photographic developers Download PDFInfo
- Publication number
- US1933804A US1933804A US587810A US58781032A US1933804A US 1933804 A US1933804 A US 1933804A US 587810 A US587810 A US 587810A US 58781032 A US58781032 A US 58781032A US 1933804 A US1933804 A US 1933804A
- Authority
- US
- United States
- Prior art keywords
- developer
- soluble
- silver
- bromides
- salt
- 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
- 230000008929 regeneration Effects 0.000 title description 3
- 238000011069 regeneration method Methods 0.000 title description 3
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 description 34
- 150000001649 bromium compounds Chemical class 0.000 description 22
- 239000002244 precipitate Substances 0.000 description 19
- 238000000034 method Methods 0.000 description 18
- 229910001961 silver nitrate Inorganic materials 0.000 description 17
- 150000003839 salts Chemical class 0.000 description 15
- 230000001172 regenerating effect Effects 0.000 description 14
- 108010010803 Gelatin Proteins 0.000 description 11
- 229920000159 gelatin Polymers 0.000 description 11
- 239000008273 gelatin Substances 0.000 description 11
- 235000019322 gelatine Nutrition 0.000 description 11
- 235000011852 gelatine desserts Nutrition 0.000 description 11
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 description 11
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 10
- 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 10
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 9
- 229910052709 silver Inorganic materials 0.000 description 9
- 239000004332 silver Substances 0.000 description 9
- 229910052751 metal Inorganic materials 0.000 description 8
- 239000002184 metal Substances 0.000 description 8
- 229910052782 aluminium Inorganic materials 0.000 description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 6
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 5
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 5
- 230000009471 action Effects 0.000 description 5
- 229910052788 barium Inorganic materials 0.000 description 5
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 5
- 229910052804 chromium Inorganic materials 0.000 description 5
- 239000011651 chromium Substances 0.000 description 5
- 229910052802 copper Inorganic materials 0.000 description 5
- 239000010949 copper Substances 0.000 description 5
- 238000001914 filtration Methods 0.000 description 5
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 5
- 229910052759 nickel Inorganic materials 0.000 description 5
- 229910052725 zinc Inorganic materials 0.000 description 5
- 239000011701 zinc Substances 0.000 description 5
- CPELXLSAUQHCOX-UHFFFAOYSA-M Bromide Chemical compound [Br-] CPELXLSAUQHCOX-UHFFFAOYSA-M 0.000 description 4
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 4
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 4
- 229910017052 cobalt Inorganic materials 0.000 description 4
- 239000010941 cobalt Substances 0.000 description 4
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 4
- 239000011133 lead Substances 0.000 description 4
- 229910052749 magnesium Inorganic materials 0.000 description 4
- 239000011777 magnesium Substances 0.000 description 4
- GRLPQNLYRHEGIJ-UHFFFAOYSA-J potassium aluminium sulfate Chemical compound [Al+3].[K+].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O GRLPQNLYRHEGIJ-UHFFFAOYSA-J 0.000 description 4
- 230000009467 reduction Effects 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 239000000470 constituent Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 229940037003 alum Drugs 0.000 description 1
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 1
- 150000001844 chromium Chemical class 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 239000000839 emulsion Substances 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000009877 rendering Methods 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
- G03C5/31—Regeneration; Replenishers
Definitions
- This invention relates to the regeneration or reconditioning of photographic developers, and to rendering them capable of further use after they have accumulated a considerable quantity of sol-,
- Our invention is carried out by adding to the spent developer'to be reconditioned a solution of a soluble silver salt, as, for example silver nitrate, containing also one of the soluble salts 5 of aluminum, chromium, cobalt, copper, nickel, bismuth, lead, barium, manganese, magnesium, and zinc. Under these conditions the silver salt forms silver bromide and the metal salt reacts with the developer in most cases to form corresponding hydroxides.
- the addition of a lit--- tle gelatin solution to the silver salt and the metal salt is advantageous, particularly if the spent developer does not contain some gelatin which has been accumulated from the film developed.
- the resulting precipitates carry down" also any gelatin or suspended matter which is still a further advantage in reconditioning the developer. After the precipitates have settled they may be filtered off or, if desired, they may 0 be centrifuged without waiting for settling.
- a preferred formula contains silver nitrate and an alum and is given in the following formula:
- the total amount of silver nitrate necessary A should for large amounts of developer preferably be calculated. This is done by making a rough determination of the amount of soluble bromides present in the developer and then adding a little more than the amount theoretically requir'edto convert the bromides to silver bromide.
- the step which includes adding to the developer a solution containing silver nitrate and a metal salt which forms an insoluble precipitate with components of the developer, said precipitate carrying down with it the silver bromide formed and protecting the said bromide from the action of the developer.
- the method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a solution containing silver nitrate and a water soluble aluminum salt, filtering off the resulting precipitate, and recovering the silver from said precipitate.
- the method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a solution containing silver nitrate and potassium aluminum sulphate, filtering off the resulting precipitate, and recovering the silver from said precipitate.
- the method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a solution containing silver nitrate, gelatin and a water soluble aluminum salt, filtering off the resulting precipitate, and recovering the silver from said precipitate.
- the method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a solution containing silver nitrate, gelatin, and potassium aluminum sulphate, filtering off the resulting precipitate, and recovering the silver from said precipitate.
- the method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a solution containing silver nitrate and a water-soluble aluminum salt.
- the method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a solution containing silver nitrate, gelatin and a water-soluble aluminum salt.
- the method of regenerating a used pho tographic developer and separating the soluble bromides therefrom comprises adding to the developer a solution containing silver nitrate, gelatin, and potassium aluminum sulfate.
- a method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a soluble silver salt and a metal salt selected from the group consisting of the water-soluble salts of aluminum, chromium, co-
- a ,method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a solution containing silver nitrate 1 and a metal salt selected from the group consisting of the water-soluble salts of aluminum, chromium, cobalt, copper, nickel, lead, barium, manganese, magnesium, and zinc.
- a method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a solution containing a soluble silver salt, gelatin, and a metal salt selected from the group consisting of the water-soluble salts of aluminum, chromium, cobalt, copper, nickel, lead, barium, manganese, magnesium, and zinc.
- a method of regenerating a used photographic developer and separating the soluble bromides therefrom which comprises adding to the developer a solution containing silver nitrate, gelatin, and a metal salt selected from the group consisting of the water-soluble salts of aluminum, chromium, cobalt, copper, nickel, lead, barium, manganese, magnesium, and zinc.
Description
Patented Nov. 7, 1933 UNITED STATES REGENERATION OF PHOTOGRAPHIC DEVELOPERS Kenneth C.,D. Hickman and Walter J. Weyerts,
Rochester, Company, New York N. Y., assignors to Eastman Kodak Rochester, N. Y., a corporation of No Drawing. Application January 20, 1932 Serial No. 587,810
14 Claims.
This invention relates to the regeneration or reconditioning of photographic developers, and to rendering them capable of further use after they have accumulated a considerable quantity of sol-,
uble bromides.
After the ordinary photographic developer is used it gradually accumulates larger and larger quantities of soluble bromides through the double decomposition and consequent reduction of silver bromide in the emulsion to metallic silver. As the quantity of bromide increases the developer becomes slower in its action until it becomes relatively useless. While this action is also accompanied by the gradual oxidation of the developer, under most normal conditions the accumulation of bromide will take place first and be the more important factor in the exhaustion of the developer.
It is apparent that if the accumulated bromides could be removed the developer could be restored or reconditioned so that it would again function in the manner similar to fresh developer of the same composition. On account of the very complex chemical nature of a photographic developer, however, it has not heretofore been possible to successfully accomplish the removal of the soluble bromides. If, for example, one adds to such a spent developer a solution of a silver salt the soluble bromides will be precipitated in the form of silver bromide but will very quickly be reduced to metallic silver by the action of the developer. In this process a large part of the bromides will again be released into the solution together with the other constituent of the silver salt'added and the precipitate which can be recovered will represent only the silver of the added silver salt. To remove the silver bromide from the developer before most of it is reduced to silver is a diiiicult problem, involving the repeated centrifuging of the material within a few seconds after precipitation.
We have found a relatively simple and easy solution of this dificulty. We find that if we add to the solution of the soluble silver salt which is to be added to the developer a soluble compound of along with the silver tective action on the silver bromide formed and both precipitates settle simultaneously without any appreciable rapid reduction of silver bromide by the developer. Some of these precipitates which are formed by interaction with the metallic salt and a constituent of the developer have a colloidal form and it is possible that they act somewhat in the well known role of a procertain metals a precipitate is formed bromide which has a pro-' tective colloid. Others of these precipitates are perhaps not accurately classifiable as colloidal but they appearat any rate to exert the same protective action and prevent the silver bromide from being-developed rapidly enough to be harmso ful.
Our invention is carried out by adding to the spent developer'to be reconditioned a solution of a soluble silver salt, as, for example silver nitrate, containing also one of the soluble salts 5 of aluminum, chromium, cobalt, copper, nickel, bismuth, lead, barium, manganese, magnesium, and zinc. Under these conditions the silver salt forms silver bromide and the metal salt reacts with the developer in most cases to form corresponding hydroxides. The addition of a lit--- tle gelatin solution to the silver salt and the metal salt is advantageous, particularly if the spent developer does not contain some gelatin which has been accumulated from the film developed. The resulting precipitates carry down" also any gelatin or suspended matter which is still a further advantage in reconditioning the developer. After the precipitates have settled they may be filtered off or, if desired, they may 0 be centrifuged without waiting for settling.
Of the salts mentioned we have fcund'silver nitrate together with a soluble aluminum or chromium salt to be as satisfactory as any. A preferred formula contains silver nitrate and an alum and is given in the following formula:
Silver nitrate 2.5 cc. of 10% solution Eotassium aluminum sulfate 7.5 cc. of 5% solution Water to 100 cc.
To this solution may be added 2 cc. of 1 percent gelatin solution. The amount of gelatin added may be varied.
The total amount of silver nitrate necessary A should for large amounts of developer preferably be calculated. This is done by making a rough determination of the amount of soluble bromides present in the developer and then adding a little more than the amount theoretically requir'edto convert the bromides to silver bromide.
It is also desirable while adding this solution to keep the temperature of the developer as low as possible. This is done for the purpose of 105 slowing up the reduction of silver bromide bythe developer and yields a consequent increase in the efficiency of the process. As is well known, developers have fairly high temperature coefficients and a moderate decrease in the tempera- 0 ample. In applying the invention to the problem special methods and apparatus will readily suggest themselves. In general it will be desirable to determine the footage of film which may be developed before reconditioning of the developer becomes necessary. This may be determined quite readily by'chemical analysis after various lengths of film have been processed. The calculation of the amount of silver nitrate to be added is then a simple matter. The developer may be run off into a special treating tank and the solution may then be filtered or centrifuged. It will be evident to those skilled in the art that various procedures may be followed at this point. It will, for example, be possible to arrange suitable equipment so that the treating, filtering or centrifuging and returning of the reconditioned developer to the system would be a more or less continuous process.
It is also understood that a large number of I variations and equivalents may be employed all of which we consider as included within our invention, as expressed by the appended claims.
What we claim is: I 1. In the method of regenerating a used photographic developer and separating the soluble bromides therefrom, the step which includes adding to the developer a solution containing a soluble silver salt and a salt which forms an insoluble precipitate with components .of the developer, said precipitate having the property of acting as a protective substance for the silver bromides formed. g
2. In the method of regenerating a used photographic developer and separating the soluble bromides therefrom, the step which includes adding to the developer a solution containing silver nitrate and a metal salt which forms an insoluble precipitate with components of the developer, said precipitate carrying down with it the silver bromide formed and protecting the said bromide from the action of the developer.
3. The method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate and a water soluble aluminum salt, filtering off the resulting precipitate, and recovering the silver from said precipitate.
4. The method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate and potassium aluminum sulphate, filtering off the resulting precipitate, and recovering the silver from said precipitate.
5. The method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate, gelatin and a water soluble aluminum salt, filtering off the resulting precipitate, and recovering the silver from said precipitate.
6. The method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate, gelatin, and potassium aluminum sulphate, filtering off the resulting precipitate, and recovering the silver from said precipitate.
'7. The method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate and a water-soluble aluminum salt.
8. The method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate and potassium aluminum sulfate.
9. The method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate, gelatin and a water-soluble aluminum salt.
10. The method of regenerating a used pho tographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate, gelatin, and potassium aluminum sulfate.
11. A method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a soluble silver salt and a metal salt selected from the group consisting of the water-soluble salts of aluminum, chromium, co-
balt, copper, nickel, lead, barium, manganese,
mangnesium, and zinc.
12. A ,method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate 1 and a metal salt selected from the group consisting of the water-soluble salts of aluminum, chromium, cobalt, copper, nickel, lead, barium, manganese, magnesium, and zinc.
13. A method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing a soluble silver salt, gelatin, and a metal salt selected from the group consisting of the water-soluble salts of aluminum, chromium, cobalt, copper, nickel, lead, barium, manganese, magnesium, and zinc.
14. A method of regenerating a used photographic developer and separating the soluble bromides therefrom, which comprises adding to the developer a solution containing silver nitrate, gelatin, and a metal salt selected from the group consisting of the water-soluble salts of aluminum, chromium, cobalt, copper, nickel, lead, barium, manganese, magnesium, and zinc.
KENNETH C. D. HICKMAN. WALTER J. WEYERTS.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US587810A US1933804A (en) | 1932-01-20 | 1932-01-20 | Regeneration of photographic developers |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US587810A US1933804A (en) | 1932-01-20 | 1932-01-20 | Regeneration of photographic developers |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US1933804A true US1933804A (en) | 1933-11-07 |
Family
ID=24351299
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US587810A Expired - Lifetime US1933804A (en) | 1932-01-20 | 1932-01-20 | Regeneration of photographic developers |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US1933804A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2689809A (en) * | 1951-10-08 | 1954-09-21 | Permachem Corp | Self-sterilizing article and its preparation |
| US4010034A (en) * | 1972-09-22 | 1977-03-01 | Konishiroku Photo Industry Co., Ltd. | Method for adjusting the bromide ion concentration in a photographic processing solution |
-
1932
- 1932-01-20 US US587810A patent/US1933804A/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2689809A (en) * | 1951-10-08 | 1954-09-21 | Permachem Corp | Self-sterilizing article and its preparation |
| US4010034A (en) * | 1972-09-22 | 1977-03-01 | Konishiroku Photo Industry Co., Ltd. | Method for adjusting the bromide ion concentration in a photographic processing solution |
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