US3716362A - Process for the removal of metallic silver from photographic material - Google Patents
Process for the removal of metallic silver from photographic material Download PDFInfo
- Publication number
- US3716362A US3716362A US00056945A US3716362DA US3716362A US 3716362 A US3716362 A US 3716362A US 00056945 A US00056945 A US 00056945A US 3716362D A US3716362D A US 3716362DA US 3716362 A US3716362 A US 3716362A
- Authority
- US
- United States
- Prior art keywords
- silver
- bath
- complexing agent
- acid
- sparingly soluble
- 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
- 229910052709 silver Inorganic materials 0.000 title claims abstract description 82
- 239000004332 silver Substances 0.000 title claims abstract description 82
- 238000000034 method Methods 0.000 title claims abstract description 53
- 239000000463 material Substances 0.000 title claims abstract description 19
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims abstract description 64
- 239000002253 acid Substances 0.000 claims abstract description 22
- 239000008139 complexing agent Substances 0.000 claims abstract description 19
- 239000007800 oxidant agent Substances 0.000 claims abstract description 19
- 230000001590 oxidative effect Effects 0.000 claims abstract description 14
- 150000001450 anions Chemical class 0.000 claims abstract description 6
- -1 silver halides Chemical class 0.000 claims description 29
- XXROGKLTLUQVRX-UHFFFAOYSA-N allyl alcohol Chemical compound OCC=C XXROGKLTLUQVRX-UHFFFAOYSA-N 0.000 claims description 14
- 239000000839 emulsion Substances 0.000 claims description 13
- 238000004061 bleaching Methods 0.000 claims description 6
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical group [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 claims description 6
- XTQHKBHJIVJGKJ-UHFFFAOYSA-N sulfur monoxide Chemical compound S=O XTQHKBHJIVJGKJ-UHFFFAOYSA-N 0.000 claims description 6
- 150000003568 thioethers Chemical class 0.000 claims description 6
- AZQWKYJCGOJGHM-UHFFFAOYSA-N 1,4-benzoquinone Chemical compound O=C1C=CC(=O)C=C1 AZQWKYJCGOJGHM-UHFFFAOYSA-N 0.000 claims description 5
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 claims description 5
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 5
- 229910052739 hydrogen Inorganic materials 0.000 claims description 4
- 239000001257 hydrogen Substances 0.000 claims description 4
- 125000000217 alkyl group Chemical group 0.000 claims description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 2
- 125000001931 aliphatic group Chemical group 0.000 claims description 2
- 125000004432 carbon atom Chemical group C* 0.000 claims description 2
- 150000002825 nitriles Chemical class 0.000 claims description 2
- JPVYNHNXODAKFH-UHFFFAOYSA-N Cu2+ Chemical class [Cu+2] JPVYNHNXODAKFH-UHFFFAOYSA-N 0.000 claims 1
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical class [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 claims 1
- 150000002431 hydrogen Chemical class 0.000 claims 1
- 150000003378 silver Chemical class 0.000 abstract description 11
- 239000007844 bleaching agent Substances 0.000 abstract description 4
- 239000010410 layer Substances 0.000 description 24
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 23
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 18
- 239000000975 dye Substances 0.000 description 16
- 239000000203 mixture Substances 0.000 description 13
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 12
- 229910052742 iron Inorganic materials 0.000 description 9
- VLTRZXGMWDSKGL-UHFFFAOYSA-M perchlorate Inorganic materials [O-]Cl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-M 0.000 description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 8
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 8
- KYQCOXFCLRTKLS-UHFFFAOYSA-N Pyrazine Chemical compound C1=CN=CC=N1 KYQCOXFCLRTKLS-UHFFFAOYSA-N 0.000 description 8
- 230000003647 oxidation Effects 0.000 description 7
- 238000007254 oxidation reaction Methods 0.000 description 7
- 150000003839 salts Chemical class 0.000 description 6
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 5
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 description 5
- 239000001117 sulphuric acid Substances 0.000 description 5
- YODZTKMDCQEPHD-UHFFFAOYSA-N thiodiglycol Chemical compound OCCSCCO YODZTKMDCQEPHD-UHFFFAOYSA-N 0.000 description 5
- 229950006389 thiodiglycol Drugs 0.000 description 5
- PCNDJXKNXGMECE-UHFFFAOYSA-N Phenazine Natural products C1=CC=CC2=NC3=CC=CC=C3N=C21 PCNDJXKNXGMECE-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 4
- 229910052802 copper Inorganic materials 0.000 description 4
- 239000010949 copper Substances 0.000 description 4
- IOLCXVTUBQKXJR-UHFFFAOYSA-M potassium bromide Chemical compound [K+].[Br-] IOLCXVTUBQKXJR-UHFFFAOYSA-M 0.000 description 4
- 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 4
- 229910021653 sulphate ion Inorganic materials 0.000 description 4
- ODJQKYXPKWQWNK-UHFFFAOYSA-N 3,3'-Thiobispropanoic acid Chemical compound OC(=O)CCSCCC(O)=O ODJQKYXPKWQWNK-UHFFFAOYSA-N 0.000 description 3
- 229920002284 Cellulose triacetate Polymers 0.000 description 3
- QXNVGIXVLWOKEQ-UHFFFAOYSA-N Disodium Chemical compound [Na][Na] QXNVGIXVLWOKEQ-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 239000003490 Thiodipropionic acid Substances 0.000 description 3
- NNLVGZFZQQXQNW-ADJNRHBOSA-N [(2r,3r,4s,5r,6s)-4,5-diacetyloxy-3-[(2s,3r,4s,5r,6r)-3,4,5-triacetyloxy-6-(acetyloxymethyl)oxan-2-yl]oxy-6-[(2r,3r,4s,5r,6s)-4,5,6-triacetyloxy-2-(acetyloxymethyl)oxan-3-yl]oxyoxan-2-yl]methyl acetate Chemical compound O([C@@H]1O[C@@H]([C@H]([C@H](OC(C)=O)[C@H]1OC(C)=O)O[C@H]1[C@@H]([C@@H](OC(C)=O)[C@H](OC(C)=O)[C@@H](COC(C)=O)O1)OC(C)=O)COC(=O)C)[C@@H]1[C@@H](COC(C)=O)O[C@@H](OC(C)=O)[C@H](OC(C)=O)[C@H]1OC(C)=O NNLVGZFZQQXQNW-ADJNRHBOSA-N 0.000 description 3
- 150000007513 acids Chemical class 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 3
- 229910017604 nitric acid Inorganic materials 0.000 description 3
- 150000004690 nonahydrates Chemical class 0.000 description 3
- 235000019303 thiodipropionic acid Nutrition 0.000 description 3
- MSSOQDMBUKCNTK-UHFFFAOYSA-N 4-(4-sulfophenyl)sulfanylbenzenesulfonic acid Chemical compound C1=CC(S(=O)(=O)O)=CC=C1SC1=CC=C(S(O)(=O)=O)C=C1 MSSOQDMBUKCNTK-UHFFFAOYSA-N 0.000 description 2
- XFXPMWWXUTWYJX-UHFFFAOYSA-N Cyanide Chemical compound N#[C-] XFXPMWWXUTWYJX-UHFFFAOYSA-N 0.000 description 2
- FOIXSVOLVBLSDH-UHFFFAOYSA-N Silver ion Chemical compound [Ag+] FOIXSVOLVBLSDH-UHFFFAOYSA-N 0.000 description 2
- 241000282887 Suidae Species 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 229960000583 acetic acid Drugs 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 2
- 239000003446 ligand Substances 0.000 description 2
- KMUONIBRACKNSN-UHFFFAOYSA-N potassium dichromate Chemical compound [K+].[K+].[O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O KMUONIBRACKNSN-UHFFFAOYSA-N 0.000 description 2
- IIACRCGMVDHOTQ-UHFFFAOYSA-N sulfamic acid Chemical compound NS(O)(=O)=O IIACRCGMVDHOTQ-UHFFFAOYSA-N 0.000 description 2
- 235000011149 sulphuric acid Nutrition 0.000 description 2
- UVZICZIVKIMRNE-UHFFFAOYSA-N thiodiacetic acid Chemical compound OC(=O)CSCC(O)=O UVZICZIVKIMRNE-UHFFFAOYSA-N 0.000 description 2
- YCGAZNXXGKTASZ-UHFFFAOYSA-N thiophene-2,5-dicarboxylic acid Chemical class OC(=O)C1=CC=C(C(O)=O)S1 YCGAZNXXGKTASZ-UHFFFAOYSA-N 0.000 description 2
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 2
- KWVBRSCGNDWTKU-UHFFFAOYSA-N (2-amino-3-methylphenyl) hydrogen sulfate Chemical compound CC1=CC=CC(OS(O)(=O)=O)=C1N KWVBRSCGNDWTKU-UHFFFAOYSA-N 0.000 description 1
- VZSRBBMJRBPUNF-UHFFFAOYSA-N 2-(2,3-dihydro-1H-inden-2-ylamino)-N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]pyrimidine-5-carboxamide Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)C(=O)NCCC(N1CC2=C(CC1)NN=N2)=O VZSRBBMJRBPUNF-UHFFFAOYSA-N 0.000 description 1
- BDKLKNJTMLIAFE-UHFFFAOYSA-N 2-(3-fluorophenyl)-1,3-oxazole-4-carbaldehyde Chemical compound FC1=CC=CC(C=2OC=C(C=O)N=2)=C1 BDKLKNJTMLIAFE-UHFFFAOYSA-N 0.000 description 1
- WBBPRCNXBQTYLF-UHFFFAOYSA-N 2-methylthioethanol Chemical compound CSCCO WBBPRCNXBQTYLF-UHFFFAOYSA-N 0.000 description 1
- AJIRUIWLEVHQMU-UHFFFAOYSA-N 3-aminophenazin-2-ol Chemical compound C1=CC=C2N=C(C=C(C(N)=C3)O)C3=NC2=C1 AJIRUIWLEVHQMU-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
- SJVGFKBLUYAEOK-SFHVURJKSA-N 6-[4-[(3S)-3-(3,5-difluorophenyl)-3,4-dihydropyrazole-2-carbonyl]piperidin-1-yl]pyrimidine-4-carbonitrile Chemical compound FC=1C=C(C=C(C=1)F)[C@@H]1CC=NN1C(=O)C1CCN(CC1)C1=CC(=NC=N1)C#N SJVGFKBLUYAEOK-SFHVURJKSA-N 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- CPELXLSAUQHCOX-UHFFFAOYSA-M Bromide Chemical compound [Br-] CPELXLSAUQHCOX-UHFFFAOYSA-M 0.000 description 1
- 241000861718 Chloris <Aves> Species 0.000 description 1
- 101710184444 Complexin Proteins 0.000 description 1
- 101100001670 Emericella variicolor andE gene Proteins 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 229910021607 Silver chloride Inorganic materials 0.000 description 1
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 239000002775 capsule Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 235000015165 citric acid Nutrition 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- SOCTUWSJJQCPFX-UHFFFAOYSA-N dichromate(2-) Chemical compound [O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O SOCTUWSJJQCPFX-UHFFFAOYSA-N 0.000 description 1
- 230000005518 electrochemistry Effects 0.000 description 1
- 239000012362 glacial acetic acid Substances 0.000 description 1
- 125000000623 heterocyclic group Chemical group 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- MAJZZCVHPGUSPM-UHFFFAOYSA-N nitric acid nonahydrate Chemical compound O.O.O.O.O.O.O.O.O.O[N+]([O-])=O MAJZZCVHPGUSPM-UHFFFAOYSA-N 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- GEVPUGOOGXGPIO-UHFFFAOYSA-N oxalic acid;dihydrate Chemical compound O.O.OC(=O)C(O)=O GEVPUGOOGXGPIO-UHFFFAOYSA-N 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 150000004053 quinones Chemical class 0.000 description 1
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 235000017281 sodium acetate Nutrition 0.000 description 1
- 229940087562 sodium acetate trihydrate Drugs 0.000 description 1
- AJPJDKMHJJGVTQ-UHFFFAOYSA-M sodium dihydrogen phosphate Chemical compound [Na+].OP(O)([O-])=O AJPJDKMHJJGVTQ-UHFFFAOYSA-M 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 125000000446 sulfanediyl group Chemical group *S* 0.000 description 1
- DHCDFWKWKRSZHF-UHFFFAOYSA-L thiosulfate(2-) Chemical compound [O-]S([S-])(=O)=O DHCDFWKWKRSZHF-UHFFFAOYSA-L 0.000 description 1
- 238000005406 washing 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
- G03C5/40—Chemically transforming developed images
- G03C5/44—Bleaching; Bleach-fixing
-
- 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
- G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
- G03C7/28—Silver dye bleach processes; Materials therefor; Preparing or processing such materials
-
- 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
- G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
- G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
- G03C7/42—Bleach-fixing or agents therefor ; Desilvering processes
- G03C7/421—Additives other than bleaching or fixing agents
Definitions
- ..G03c 7/00, G036 5/50, G036 5/32 Pr comprises treating the photographic material [58] Field 61 Search ..96/20, 53,61,- 59, 60 with a acid bath free from that form sparingly 1 1 soluble silver salts and which bath contains an'oxidant [56] R fe Cit -d and a complexing agent.
- the oxidant has a standard redox potential of at most +0.8 Voltsand the com- UNITED STATES PATENTS plexing agent has a silver complex stability constant of 2,304,987 12/1942 Young; .Q ..96/60 109 (liter/mole)?
- the primarily developed silver must be removed without attacking any residual, undeveloped silver halide since in a further process step the latter is developed to the positive silver image.
- This can be done with oxidation baths which convert the silver into a soluble silver salt which can diffuse out of the photographic layer, for example, a sulphuric acid solution of potassium dichromate'orpotassium permanganate, for
- the oxidation of silver and .the washing out of the silver halide may-be carried out in separate baths by first oxidizing the silver and then dissolving the silver halide.
- oxidation of the silver may also be carried out with a solution that converts the silver into a sparingly soluble silver salt, forexample a hydrochlo-' ric acid solution of copper(ll)chlori de or a solution of potassium-iron(lll)cyanide since the sparingly soluble silver salts formed remain in the layer and are removed during the subsequent fixing operation.
- oxidation baths such as dichromate-sulphuric acid, cannot be used since theseoxidants also decompose other componentspresent in thephotographic layer.
- Suitable oxidants are copper(ll)salts or more especially quinones and iron(lll)salts. Particularly good resultsare obtained with iron(lll)salts, for example iron(lll)perchlorate,
- iron(lll)nitrate or ammonium iron(lll) sulfate According to this invention only anions that do not form sparingly soluble silver salts can be used.
- the oxidation potential of these oxidants must be below +0.8 Volt,
- the standard redox potential of the following elec rro-chemical reactions is, for example:
- complexin'g'agents are those which display a silver complex stability constant of from 10" to 10 (liter/mole).
- com plexing agents having a silver complex stability constant within this range are water-solubleunsaturated compounds,for example allyl alcohol,initriles, for example acetonitrile, certain heterocyclic amines, for example pyrazine, and thioethers'
- Especially suitable complexing agents are those having a silver complex stability constant of from 10 to 10 (liter/moleY, especially water-soluble thioethers, and preferably monothiosethers.
- water-soluble aliphatic monothioethers which corresponds to the formula v I r'- r 2 2 inwhich R, and R, whichmay be the same or different each represent an alkyl group containing from one to threecarbon' atoms, and X and X each represent a hydrogen atom or a hydroxyl or carboxyl group.
- Suitable water solublethioethers are, for example:
- water-soluble thioethers in "which R and R are aromatic or heterocyclic residues, for example the disodium saltof di-(para-sulphophenyl)-sulphide, 'or the free acid thereof.
- cyclic water-soluble thioethers 'such as thiophene- 2,5-dicarboxylic acids which correspond, for example, to the formula in which X, and X have the meanings defined above.
- the pH value of the treatment bath should advantageously be below 6.
- Acids suitable foradjusting the pH value are, for example, sulphamic acid, sulphuric acid, oxalic acid, citric acid, perchloric acid, nitric acid and other acids capable of forming readily soluble silver salts.
- the salts of the oxidant for example copper sulphate, form acid solutions'in water it is not necessary to add additional acid to the treatment bath.
- the proportions of the individual constituents may be varied within wide limits. It is also possible to use mixtures containing more than one of each of the acids, oxidants and complexing agents.
- the bath may further contain conventional additives, such as surface-active- I colored image by diffuse light and second development 54, pages 264 276 [1958] andE. Larsson in the book or by development in the presence of a fogging agent, or by sulphidation. i
- the invention is of special importance in carrying out the silver dye bleach-negative-positive process.
- a material that contains photosensitive silver -halide and a dyestuff; On exposure and development a silver image is formed whose gradation is the opposite of that of the master (negative silver image).
- a color gradation is achieved which is opposite to that of the silver image, that is to say equal to that of the master.
- a positive color image of a positive master is obtained.
- a reversal f to metallic silver and then decomposing the dyestuff the metallic silver and the sparingly. soluble silver salt are contained in the same silver emulsion layer. This is the case whenever the metallic silver is distributed to form an image, especially inreversal processes where a primarily .developed silver image isdissolved and the residual silver salt image is converted into a black or depending on the amount of silver present in the layer, and removing the primary silver image by means of an acid bath which is free from anions that form sparingly soluble silver salts and which contains an oxidant and a complexing agent capable of forming with silver complexes of little stability;
- the temperature of the silverbleaching bath and the treatment time may be varied within wide limits without incurring a loss of undeveloped silver halide.
- the present process is applicable to the treatment of both single-layer and multilayer color materials, of materials for viewing in incident light and transparencies, of mixed grain emulsion layers and of materials with incorporated capsules.
- a rapid reversal process can be carried out with a metarial which contains acid, oxidant and complexing agents in crushable pods.
- Another variant starts from a material that contains oxidant and complexing agents in-pods which disintegrate only when they come into contact with an acid bath.
- the process according to the present invention is of special value in connection with reversal processes but the invention is also suitable for other processes in which metallic silver (such as developed image silver, latent image nuclei or colloidal silver) is dissolved without affecting any sparingly soluble silver salts present (which are present in the same grain, in the same layer or in another layer).
- metallic silver such as developed image silver, latent image nuclei or colloidal silver
- EXAMPLE 1 Two strips of a blue-sensitized emulsion layer on a cellulose triacetate base, containing 0.7 g of silver bromide and 0.12 g of a yellow dyestuff of the formula are chosen according a nous n 5,0 11 per square meter, are exposed under a stepped wedge. The exposed strips are developed with a commercial para-methylaminophenol sulphate/hydroquinone developer and the development process is stopped with a 3 percent solution .of acetic acid. After having been washed in water for 1 minute, one strip is treated for 3 minutes'a'nd the other strip for 10 minutes with a solution'of thefollowing composition to remove the metallic silver left in the layer after the first development:
- strips are treated for 6 minutes with a commercial p-' methyl-aminophenol-sulphate/hydroquinone Hydrochloric acid, 37% strength 70 ml potassium bromide 50 g thiourea 80 g 2-amino-3-hydroxyphenazine 5 mg water, to l liter.
- Potassium iron(lll)cyanide 75 g potassium bromide l5 g primary sodium phosphate monohydrate [0 g g sodium acetate trihydrate I 5 g glacial acetic acid l0 ml water, to Y l liter.
- strips are then rinsedin water for 1 minute and fixed with an acid'thio'sulphate solution in the known manner. Both strips'carry identical yellow images of the stepped wedge used for the exposure, which are negative with respect to the master.
- EXAMPLE 4 Instead of the bath described in Example 2 a solution of the following composition is usedr lron(lll)p crchlorate nonahydrate 52 g perchloric acid, strength 150 g disodium salt of di-(p-sulphophenyl)-sulphide g water, to 1 liter pH value: 0.6.
- a photographic tripack material which carried on a allyl alcohol 8 b l 1) I (l l water, to 20 transparent ase a red-sensitized Sl ver rorm eemu pH value: 0.35.
- the silver halide left in the layer is then reduced to metallic silver with the developer used in Example 1.
- the resulting silver image of the grey wedge used for the exposure is a positive reproduction of the master.
- EXAMPLE 14 A strip of an emulsion layer on an opaque cellulose triacetate base, sensitive to red light, which carries per square meter of base 0.7 g of silver bromide and 0.115 g of the cyan dyestuff of the formula (4) is exposed under a stepped wedge and then processed as described in Example l, except that the metallic silver left in the layer after the first development is removed with a bath of the following composition:
- Ammonium-iron(lll)sulphate dodecahydrate 60 g 2N-sulphuric acid 100 ml pyrazine 50 g 1 liter water, to
- the resulting cyan-colored image is a negative of the stepped wedge used for the exposure.
- Example 14 The process described in Example 14 is used, except that the metallic silver formed after the first development is removed with a bath of the following composition:
- lron(lll)nitrate nonahydrate 40 g 2N-nitric acid 100 ml pyrazine 50 8 water, to 1 liter pH value: 0.8.
- Example 14 As in Example 14 a cyan-colored image is obtained which is a negative reproduction of the stepped wedge used for the exposure.
- a process as claimed in claim 1, wherein the complexing agent is a monothioether of the formula in which R, and R which may be the same or different, each represents alkyl having at most three carbon atoms, and X, and X which may be the same or different, each represents hydrogen or hydroxyl or carboxyl.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Silver Salt Photography Or Processing Solution Therefor (AREA)
Abstract
A process for removing metallic silver from photographic materials is provided, wherein any sparingly soluble silver salts present are not attacked. This process comprises treating the photographic material with an acid bath free from anions that form sparingly soluble silver salts and which bath contains an oxidant and a complexing agent. The oxidant has a standard redox potential of at most +0.8 Volts and the complexing agent has a silver complex stability constant of at most 109 (liter/mole)2. This process is of special importance in carrying out the silver dye bleach negative-positive process. The main advantage of the process is the fact that it uses only a small number of bathes and no strong oxidants.
Description
United States Patent 1191 Meier 1 1 Feb; 13, 1973 1541 PROCESS FOR THE REMOVAL OF 2,699,394 1/1955 Gaspar .;...:.....96/99 METALLIC SILVER FROM PHOTOGRAPH: AL FOREIGN PATENTS OR APPLICATIONS [75] Inventor: Max Meier, pfi Switzerland 739,202 10/1955 Great Britain.' ..96 60 7 [731 Assignees Ciba-Geigy AG, Basle, Switzerland primary Examiner Travis Brown [22] Filed; July. 21 1970 Assistant Examiner-M. F. Kelley Attorney-Harry Goldsmith, Joseph G. Kolodny and 21 Appl. No.: 56,945 MarioA Monaco v [30] Foreign Application Priority Data [57] ABSTRACT July 30, 1969 Switzerland ..11605/69 A Process for removing metallic Silver from P graphic materials is provided, wherein any sparingly 52 Us. (:1 ..96/60 R, 96/53, 96/59 Soluble Silver Salts present are not attacked. This 511 Int. Cl. ..G03c 7/00, G036 5/50, G036 5/32 Pr comprises treating the photographic material [58] Field 61 Search ..96/20, 53,61,- 59, 60 with a acid bath free from that form sparingly 1 1 soluble silver salts and which bath contains an'oxidant [56] R fe Cit -d and a complexing agent. The oxidant has a standard redox potential of at most +0.8 Voltsand the com- UNITED STATES PATENTS plexing agent has a silver complex stability constant of 2,304,987 12/1942 Young; .Q ..96/60 109 (liter/mole)? This Process is 0f Special 2 74 0'0 5 95 portance in carrying out the silver dyebleach nega- 2,020,775 11/1935 Gaspar....= ..96/53 fi -p t p c s T m in ad n ge of the 2,113,329 1 4/1938 Mannes et al.. .....96/55 process is the fact that it uses only a small number of 2,322,001 6/1943 Ehrenfried ..96/53 bathes and no strong oxidants. 2,322,084 6/!943 Young, ..96/53 11/1950 Vittum ..96/60 9 Claims, No Drawings 1 PROCESS FOR THE REMOVAL OF METALLIC SILVER FROM PHOTOGRAPHIC MATERIAL The present invention relates to a process for removing metallic silver from photographic materials.
A number of processes are known forremoving silver and silver halides from photographic materials. The choice of'the process to be applied depends on the requirements of the individual photographic process.
,Thus, in -the conventional production of a silver image by developing exposed silver halide it is necessary to remove the residual, undeveloped silver halide, forexample by means of a solution of thiosulphate.
- In a direct positive development, on the other hand,-
the primarily developed silver must be removed without attacking any residual, undeveloped silver halide since in a further process step the latter is developed to the positive silver image. This can be done with oxidation baths which convert the silver into a soluble silver salt which can diffuse out of the photographic layer, for example, a sulphuric acid solution of potassium dichromate'orpotassium permanganate, for
which purpose the standard redox potential of these solutions must be greater than +0.8. Volt, which is the standard potential of Ag Ag". v
In other photographic processes, especially color I processes, both the silver and. any silverhalide must be removed; this can be done with so-called bleach fixing bathssthat contain an oxidant as well as a solvent for silver halide, for example Farmers reducer or bleach fixing baths, described in German specification No. .l ,l46,-36 3 and US. Pat. No. 2,748,000.
If desired, the oxidation of silver and .the washing out of the silver halide. may-be carried out in separate baths by first oxidizing the silver and then dissolving the silver halide. In this case oxidation of the silver may also be carried out with a solution that converts the silver into a sparingly soluble silver salt, forexample a hydrochlo-' ric acid solution of copper(ll)chlori de or a solution of potassium-iron(lll)cyanide since the sparingly soluble silver salts formed remain in the layer and are removed during the subsequent fixing operation.
For certain reversal processes, however, oxidation baths, such as dichromate-sulphuric acid, cannot be used since theseoxidants also decompose other componentspresent in thephotographic layer.
Thus, strong oxidants-cannot be used ina silver reversal development within the framework of the silver dye bleach-negative positive process since many of the azo dyestuffs used in this process may be destroyed by oxidation. While it is possiblejin such a case to adopt the procedure proposed in German specification No. l,l54,347, this process is cumbersome since it requires several additional treatment one emulsion layer, wherein the said material is treated with anacid bath which is free from anions that form sparingly soluble silver salts and contains 1. one or more oxidants having a standard redox potential ofat most-+0.8 ,Volt and;
2. a complexing agent having a silver complex stability constant of'at most l0 (liter/mole The standard'redox potential of the oxidant should husually be within the range from +0.15 to +0.8 Volt,
preferably from'+0.4 to +0.8 Volt. Suitable oxidants are copper(ll)salts or more especially quinones and iron(lll)salts. Particularly good resultsare obtained with iron(lll)salts, for example iron(lll)perchlorate,
iron(lll)nitrate or ammonium iron(lll) sulfate. According to this invention only anions that do not form sparingly soluble silver salts can be used. The oxidation potential of these oxidants must be below +0.8 Volt,
the oxidation potential of Ag Ag.
. The standard redox potential of the following elec rro-chemical reactions is, for example:
Fe e ,2 Fee +0.77-v olt Ca ce :2 011+ +0.17 volt Benzodulnone 211* 2e hydroquinone +0.7 volt Preferably used complexin'g'agents are those which display a silver complex stability constant of from 10" to 10 (liter/mole). Among the com plexing agents having a silver complex stability constant within this range are water-solubleunsaturated compounds,for example allyl alcohol,initriles, for example acetonitrile, certain heterocyclic amines, for example pyrazine, and thioethers' Especially suitable complexing agents are those having a silver complex stability constant of from 10 to 10 (liter/moleY, especially water-soluble thioethers, and preferably monothiosethers. Ofspecial:
value are water-soluble aliphatic monothioethers, which corresponds to the formula v I r'- r 2 2 inwhich R, and R, whichmay be the same or different each represent an alkyl group containing from one to threecarbon' atoms, and X and X each represent a hydrogen atom or a hydroxyl or carboxyl group.
Suitable water solublethioethers are, for example:
thiodiglycollic acid,
thiodipropionic acid,
'2 hyd'roxyethyl-methylsulphide thiodiglycol.
and
Apart from the aliphatic monothioethers of the formula l it is possible to use water-soluble thioethers in "which R and R are aromatic or heterocyclic residues, for example the disodium saltof di-(para-sulphophenyl)-sulphide, 'or the free acid thereof. Further suitable are cyclic water-soluble thioethers, 'such as thiophene- 2,5-dicarboxylic acids which correspond, for example, to the formula in which X, and X have the meanings defined above.
especially I Very weak complexing agents, such as allyl alcohol The Svedberg, Uppsala 1944, pages 311 319. The
stability constant of the complex of silver ion with acetonitrile: see F.G. Pawelka, Zeitschr. Elektrochemie 30, page 180 [1924]; the stability constant of the com plex of silver ion with allyl alcohol: see S. Winstein and HJ. Lucas, J.Am.Chem.Soc.60, page 836 [1938].
The stability constant K of the reaction Agni) where L-.represents the ligand concerned. For some suitable ligands the K-value in-(Liter/mole) is, for example,'as follows:-
Thiodiglycol Z-hydroxyethyl-rnethyls'ulphide 10 disodium salt of di-(p-sulphonyl)-sulphide lthiodiglycollic acid thiodipropionic acid l0 acetonitrile 10" allyl alcohol 10" pyrazine 1 0" The pH value of the treatment bath should advantageously be below 6. Acids suitable foradjusting the pH value are, for example, sulphamic acid, sulphuric acid, oxalic acid, citric acid, perchloric acid, nitric acid and other acids capable of forming readily soluble silver salts. When the salts of the oxidant, for example copper sulphate, form acid solutions'in water it is not necessary to add additional acid to the treatment bath.
The proportions of the individual constituents may be varied within wide limits. it is also possible to use mixtures containing more than one of each of the acids, oxidants and complexing agents. The bath may further contain conventional additives, such as surface-active- I colored image by diffuse light and second development 54, pages 264 276 [1958] andE. Larsson in the book or by development in the presence of a fogging agent, or by sulphidation. i
The invention is of special importance in carrying out the silver dye bleach-negative-positive process. In the usual silver dye bleaching process a material is used that contains photosensitive silver -halide and a dyestuff; On exposure and development a silver image is formed whose gradation is the opposite of that of the master (negative silver image). By decomposing the dyestuff on the silver a color gradation is achieved which is opposite to that of the silver image, that is to say equal to that of the master. Thus, a positive color image of a positive master is obtained.
To produce a positive color image from a negative master by the silver dye bleach process, a reversal f to metallic silver and then decomposing the dyestuff the metallic silver and the sparingly. soluble silver salt are contained in the same silver emulsion layer. This is the case whenever the metallic silver is distributed to form an image, especially inreversal processes where a primarily .developed silver image isdissolved and the residual silver salt image is converted into a black or depending on the amount of silver present in the layer, and removing the primary silver image by means of an acid bath which is free from anions that form sparingly soluble silver salts and which contains an oxidant and a complexing agent capable of forming with silver complexes of little stability;
When the acid and the oxidant to this invention, the bleachable dyestuff is not attacked and this makes the present process superior to the dichromate process. The superiority over the process according to German specification No. 1,154,347 is based on the fact that the present process requiresa smaller number of baths.
The temperature of the silverbleaching bath and the treatment time may be varied within wide limits without incurring a loss of undeveloped silver halide.
The present process is applicable to the treatment of both single-layer and multilayer color materials, of materials for viewing in incident light and transparencies, of mixed grain emulsion layers and of materials with incorporated capsules. Thus, for example, a rapid reversal process can be carried out with a metarial which contains acid, oxidant and complexing agents in crushable pods. Another variant starts from a material that contains oxidant and complexing agents in-pods which disintegrate only when they come into contact with an acid bath. I
The process according to the present invention is of special value in connection with reversal processes but the invention is also suitable for other processes in which metallic silver (such as developed image silver, latent image nuclei or colloidal silver) is dissolved without affecting any sparingly soluble silver salts present (which are present in the same grain, in the same layer or in another layer).
In the following Examples, which illustrate the invention, all percentages are percentages by weight.
EXAMPLE 1 Two strips of a blue-sensitized emulsion layer on a cellulose triacetate base, containing 0.7 g of silver bromide and 0.12 g of a yellow dyestuff of the formula are chosen according a nous n 5,0 11 per square meter, are exposed under a stepped wedge. The exposed strips are developed with a commercial para-methylaminophenol sulphate/hydroquinone developer and the development process is stopped with a 3 percent solution .of acetic acid. After having been washed in water for 1 minute, one strip is treated for 3 minutes'a'nd the other strip for 10 minutes with a solution'of thefollowing composition to remove the metallic silver left in the layer after the first development:
lron-lll-perchlorate nonahydrate 52 gsulphamic acid 60 g thiodiglycol l2.5 g water, to pH value: 0.35. 1 liter.
After having been rinsed in water for 4 minutes, the
strips are treated for 6 minutes with a commercial p-' methyl-aminophenol-sulphate/hydroquinone Hydrochloric acid, 37% strength 70 ml potassium bromide 50 g thiourea 80 g 2-amino-3-hydroxyphenazine 5 mg water, to l liter.
After 6 minutes immersion the strips are rinsed in water and treated with a silver bleaching bath of the following composition:
Potassium iron(lll)cyanide 75 g potassium bromide l5 g primary sodium phosphate monohydrate [0 g g sodium acetate trihydrate I 5 g glacial acetic acid l0 ml water, to Y l liter.
The strips are then rinsedin water for 1 minute and fixed with an acid'thio'sulphate solution in the known manner. Both strips'carry identical yellow images of the stepped wedge used for the exposure, which are negative with respect to the master.
EXAMPLE 2 The procedure used is as described in Example l, ex v cept that the metallic silver left after the first development is removed with a bath composed as follows:
lron(lll)perchlorate nonahydrate .28 g 2 N-nitric acid 50 ml Z-hydroxyethyl-methylsulphide 9.6 gv water, to l liter.
pH value: 0.65]
The? resulting pictures are Gil; SOalI EXAMPLE 3 Instead of the bath described in Example 2 a solution I of the following compositionis used.: I
Benzoquinone, dissolved in 200 ml of methanol l0.8 g ZN-sulphuric acid 50 ml 2-hydroxyethyl-methylsulphide l(l)|g iter water, to
pH value: 0.8
The resulting images are identical to those described in'Example l. p v
EXAMPLE 4 Instead of the bath described in Example 2 a solution of the following composition is usedr lron(lll)p crchlorate nonahydrate 52 g perchloric acid, strength 150 g disodium salt of di-(p-sulphophenyl)-sulphide g water, to 1 liter pH value: 0.6.
The resulting images'are identical to those of Example l. I
EXAMPLES instead of the bath described in Example 2 a solution of the following composition is used:
lron(lll)perchlorate nonahydrate 52 g thiodiglycolic acid 15 g uulphumic acid 60 g water. to I l liter pH value: 0.35.
The resulting images are identical to those of Exam- 'ple 1.
I EXAMPLE6 instead of the bath describedin Example 2 a solution of the following composition is used:
lron(lll)perchlorate nonahydrate 52 g thiodipropionic acid 18 g sulphamic acid 60 g water, to 1 liter pH value: 0.35.
described in Example I.
EXAMPLE 7.
instead of the bath'described in Example 2 a solution of the following composition'isused: a
lron(lll)perchlorate nonahydrate 52 g sulphamic'acid 60 g water, to 1 liter thiophene-2,5-dicarboxylic acid to saturation The resulting images are identical to those obtained A as described in Example 1.
pH value: 0.35
The-resultingimages areidentical to those of Examplel.
identical to those EXAMPLE 8 is exposedunder a grey wedge andthen processed as described in Example 1, except that the metallic silver left in the layer after the first development is removed with a bath of the following composition:
lnstead of the bath described in Example 2 a solution of the following composition is used:
5 lron(lll)perchlorate nonahydrate 52 g v sulpharmc acid 60 g lr0n(lll)perchlorate nonahydrate' 52 g acetonitrile I00 g oxalic acid dihydrate 40 g water, to l lltur thiodiglycol 12.5 g
- pH value: 0.35. water, to l liter pH value: 0.35.
The resulting images are identical to those described in Example 1.
. for the exposure IS a negative of the. master. Identical EXAMPLE 9 results are obtained in the 3-minutes and the 10 Instead of the bath described in Example 2 a solution minutes test l5 ofthe following composition 18 used:
EXAMPLE l2 lron(lll)pcrchlorate nonahydrate 52 g sulphflmw 8 A photographic tripack material which carried on a allyl alcohol 8 b l 1) I (l l water, to 20 transparent ase a red-sensitized Sl ver rorm eemu pH value: 0.35. sion containing acyan dyestuff as described in Example s 10, covered by a green-sensitized emulsion layer con- I The resulting images are ldem to those of EXamtaining a magenta dyestuff asdescribed in Example 1 l, P I which layer in turn is coveredby a blue-sensitized silver 1 EXAMPLE 10 bromide emulsion layer containingv a yel ow azo N=N.N= i Hogs S0311 (511.6
. dyestuff as described in Example 1,. is exposed under a -A red-sensitized emulsion layer which contains per grey wedge. Processing is carried out as described in square meter of cellulose triacetate base 0.7 gm of Example 1, except that the metallic silver left in the silver bromide and 0.1 15 g of a blue-green dyestuff of layer after the first development is removed with a bath the formula I of the following composition:
OuH
40 is exposed under a stepped wedge and then processed Copper(ll)sulphate pentahydrate 125 g as described in Example 1, except that the metallic sg g g Y i' g silver left in the layer after the first development is pH value:3.5. removed with a bath com osed as follows: I
p v A reproduction of the grey wedge used for the expolmnmngechloraw nonahydrate Y 52 g sure rs obtained which 15 a negative of the master. citric aci ihydrate 1 52 g thiodiglycol 12.8 g EXAMPLE 13 water, to 1 lit v I pH value: 0.5. A commercial enlarging paper, whose emulsion layer contains a silver halide consisting of 54 mol percent of A blue-green image of the stepped wedge used for silver chloride and 47 mol percent of silver bromide, is the exposure'is obtained which is negative with respect exposed under a grey wedge and then developed with a to the master. No differences can be noted by comparcommercial .merh l i h l ing the results ofthe 3-minutes test with those of the gulphate/hydroquinone ,developer. After having been lO-mmutes test. 5S rinsed in water for 2 minutes the paper is immersed in a solution of the followin com osition: EXAMPLE 1 1 g p g lron(lll)perchlorate nonahydrate 52 g A green-sensit zed emulsion layer which contains per lp i acid 2 square meter of a t'riacetate base 0.7 g of silver bromide sg'ig g g lter and 0.150 g ofa magenta dyestuff of the formula 6 pH value: 0.35.
(5) Hogs I soar The resulting magenta image of the grey wedge used After 8 minutes the paper is rinsed in water and then exposed in diffuse light.
The silver halide left in the layer is then reduced to metallic silver with the developer used in Example 1.
The resulting silver image of the grey wedge used for the exposure is a positive reproduction of the master.
EXAMPLE 14 A strip of an emulsion layer on an opaque cellulose triacetate base, sensitive to red light, which carries per square meter of base 0.7 g of silver bromide and 0.115 g of the cyan dyestuff of the formula (4) is exposed under a stepped wedge and then processed as described in Example l, except that the metallic silver left in the layer after the first development is removed with a bath of the following composition:
Ammonium-iron(lll)sulphate dodecahydrate 60 g 2N-sulphuric acid 100 ml pyrazine 50 g 1 liter water, to
- pH value: 0.8.
The resulting cyan-colored image is a negative of the stepped wedge used for the exposure.
EXAMPLE The process described in Example 14 is used, except that the metallic silver formed after the first development is removed with a bath of the following composition:
lron(lll)nitrate nonahydrate 40 g 2N-nitric acid 100 ml pyrazine 50 8 water, to 1 liter pH value: 0.8.
As in Example 14 a cyan-colored image is obtained which is a negative reproduction of the stepped wedge used for the exposure.
Iclaim: I
1. In a process for removing metallic silver without attacking any dyestuffs or sparingly soluble silver halides present from a photographic material comprising sparingly soluble silver halides and metallic silver distributed in at least one emulsion layer on a support by the steps of exposing, developing, reversal developing, dye bleaching, silver bleaching and fixing, the improvement which comprises treating said material after the I first silver image developing bath with an acid bath free from anions that form sparingly soluble silver halides, said bath containing an oxidant selected from a copper (ll) salt, a quinone or an iron (Ill) salt, and a complexing agent selected from allyl alcohol, a nitrile and a thio-ether.
2. A process as claimed in claim 1, wherein a watersoluble aliphatic monothioether is used as complexing agent.
3. A process as claimed in claim 1, wherein the complexing agent is a monothioether of the formula in which R, and R which may be the same or different, each represents alkyl having at most three carbon atoms, and X, and X which may be the same or different, each represents hydrogen or hydroxyl or carboxyl.
4. A process as claimed in claim 1, wherein the complexing agent is a monothioether of the formula mHx. S
in which X, and X which may be the same or different,
each represents hydrogen, hydroxyl or carboxyl.
5. A process as claimed in claim 1, wherein the silver
Claims (8)
1. In a process for removing metallic silver without attacking any dyestuffs or sparingly soluble silver halides present from a photographic material comprising sparingly soluble silver halides and metallic silver distributed in at least one emulsion layer on a support by the steps of exposing, developing, reversal developing, dye bleaching, silver bleaching and fixing, the improvement which comprises treating said material after the first silver image developing bath with an acid bath free from anions that form sparingly soluble silver halides, said bath containing an oxidant selected from a copper (II) salt, a quinone or an iron (III) salt, and a complexing agent selected from allyl alcohol, a nitrile and a thio-ether.
2. A process as claimed in claim 1, wherein a water-soluble aliphatic monothioether is used as complexing agent.
3. A process as claimed in claim 1, wherein the complexing agent is a monothioether of the formulaX1-R1-S-R2-X2 in which R1 and R2 which may be the same or different, each represents alkyl having at most three carbon atoms, and X1 and X2 which may be the same or different, each represents hydrogen or hydroxyl or carboxyl.
4. A process as claimed in claim 1, wherein the complexing agent is a monothioether of the formula in which X1 and X2 which may be the same or different, each represents hydrogen, hydroxyl or carboxyl.
5. A process as claimed in claim 1, wherein the silver halide is silver bromide.
6. A process as claimed in claim 1, wherein the pH value of the bath is below 6.
7. A process as claimed in claim 1, wherein the metallic silver and the silver halide are present in the same emulsion layer.
8. A process as claimed in claim 1, carried out in a reversal development process.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1160569A CH511456A (en) | 1969-07-30 | 1969-07-30 | Process for removing metallic silver from photographic material |
Publications (1)
Publication Number | Publication Date |
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US3716362A true US3716362A (en) | 1973-02-13 |
Family
ID=4375095
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US00056945A Expired - Lifetime US3716362A (en) | 1969-07-30 | 1970-07-21 | Process for the removal of metallic silver from photographic material |
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US (1) | US3716362A (en) |
BE (1) | BE754080A (en) |
CA (1) | CA942559A (en) |
CH (1) | CH511456A (en) |
DE (1) | DE2037684A1 (en) |
FR (1) | FR2055511A5 (en) |
GB (1) | GB1324515A (en) |
NL (1) | NL7011234A (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3893858A (en) * | 1973-03-26 | 1975-07-08 | Eastman Kodak Co | Photographic bleach accelerators |
US4070188A (en) * | 1975-06-23 | 1978-01-24 | Fuji Photo Film Co., Ltd. | One bath type silver dye bleaching and silver bleaching |
US4125402A (en) * | 1976-08-19 | 1978-11-14 | Ciba-Geigy Ag | Method of processing silver dye bleaching materials and preparations suitable for the dye and silver bleaching |
US4138256A (en) * | 1975-11-17 | 1979-02-06 | Ciba-Geigy Ag | Method of processing photographic silver dye bleach materials |
US4229522A (en) * | 1977-10-26 | 1980-10-21 | Fuji Photo Film Co., Ltd. | Method for forming color images |
US4242441A (en) * | 1976-10-12 | 1980-12-30 | Fuji Photo Film Co., Ltd. | Color image forming process |
US5401621A (en) * | 1989-12-04 | 1995-03-28 | Fuji Photo Film Co., Ltd. | Method of fixing and bleach-fixing a silver halide photographic material using mesoionic compounds |
US5434035A (en) * | 1993-12-29 | 1995-07-18 | Eastman Kodak Company | Fixer additives used in combination with iron complex based bleaches to improve desilvering |
US5508150A (en) * | 1993-12-29 | 1996-04-16 | Eastman Kodak Company | Fixer additives used in combination with iron complex based bleaches to prevent iron retention |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2748430A1 (en) * | 1977-10-28 | 1979-05-03 | Agfa Gevaert Ag | PHOTOGRAPHIC BLEACHING COMPOSITIONS WITH BLADE ACCELERATING COMPOUNDS |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2020775A (en) * | 1930-11-07 | 1935-11-12 | Bela Gaspar | Method of producing photographic pictures in colors |
US2113329A (en) * | 1934-06-15 | 1938-04-05 | Eastman Kodak Co | Color photography |
US2304987A (en) * | 1940-02-22 | 1942-12-15 | Eastman Kodak Co | Method of lowering contrast of dye images |
US2322084A (en) * | 1940-01-11 | 1943-06-15 | Eastman Kodak Co | Simultaneous bleaching and fixing bath |
US2322001A (en) * | 1940-10-10 | 1943-06-15 | Eastman Kodak Co | Method of producing dye images |
US2529981A (en) * | 1945-11-28 | 1950-11-14 | Eastman Kodak Co | Bleaching silver images |
US2699394A (en) * | 1950-12-15 | 1955-01-11 | Gaspar Bela | Production of photographic dye images |
GB739202A (en) * | 1952-06-07 | 1955-10-26 | Agfa Ag | Improvements in or relating to the production of photographic colour images |
US2748000A (en) * | 1954-04-01 | 1956-05-29 | Eastman Kodak Co | Removing silver and silver halide from photographic elements |
-
1969
- 1969-07-30 CH CH1160569A patent/CH511456A/en not_active IP Right Cessation
-
1970
- 1970-07-21 GB GB3530370A patent/GB1324515A/en not_active Expired
- 1970-07-21 US US00056945A patent/US3716362A/en not_active Expired - Lifetime
- 1970-07-21 CA CA088,675A patent/CA942559A/en not_active Expired
- 1970-07-23 FR FR7027157A patent/FR2055511A5/fr not_active Expired
- 1970-07-29 NL NL7011234A patent/NL7011234A/xx unknown
- 1970-07-29 DE DE19702037684 patent/DE2037684A1/en active Pending
- 1970-07-29 BE BE754080D patent/BE754080A/en unknown
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2020775A (en) * | 1930-11-07 | 1935-11-12 | Bela Gaspar | Method of producing photographic pictures in colors |
US2113329A (en) * | 1934-06-15 | 1938-04-05 | Eastman Kodak Co | Color photography |
US2322084A (en) * | 1940-01-11 | 1943-06-15 | Eastman Kodak Co | Simultaneous bleaching and fixing bath |
US2304987A (en) * | 1940-02-22 | 1942-12-15 | Eastman Kodak Co | Method of lowering contrast of dye images |
US2322001A (en) * | 1940-10-10 | 1943-06-15 | Eastman Kodak Co | Method of producing dye images |
US2529981A (en) * | 1945-11-28 | 1950-11-14 | Eastman Kodak Co | Bleaching silver images |
US2699394A (en) * | 1950-12-15 | 1955-01-11 | Gaspar Bela | Production of photographic dye images |
GB739202A (en) * | 1952-06-07 | 1955-10-26 | Agfa Ag | Improvements in or relating to the production of photographic colour images |
US2748000A (en) * | 1954-04-01 | 1956-05-29 | Eastman Kodak Co | Removing silver and silver halide from photographic elements |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3893858A (en) * | 1973-03-26 | 1975-07-08 | Eastman Kodak Co | Photographic bleach accelerators |
US4070188A (en) * | 1975-06-23 | 1978-01-24 | Fuji Photo Film Co., Ltd. | One bath type silver dye bleaching and silver bleaching |
US4138256A (en) * | 1975-11-17 | 1979-02-06 | Ciba-Geigy Ag | Method of processing photographic silver dye bleach materials |
US4357280A (en) * | 1975-11-17 | 1982-11-02 | Ciba-Geigy Ag | Use of tertiary phosphines in photographic silver dye bleach materials |
US4125402A (en) * | 1976-08-19 | 1978-11-14 | Ciba-Geigy Ag | Method of processing silver dye bleaching materials and preparations suitable for the dye and silver bleaching |
US4242441A (en) * | 1976-10-12 | 1980-12-30 | Fuji Photo Film Co., Ltd. | Color image forming process |
US4229522A (en) * | 1977-10-26 | 1980-10-21 | Fuji Photo Film Co., Ltd. | Method for forming color images |
US5401621A (en) * | 1989-12-04 | 1995-03-28 | Fuji Photo Film Co., Ltd. | Method of fixing and bleach-fixing a silver halide photographic material using mesoionic compounds |
US5434035A (en) * | 1993-12-29 | 1995-07-18 | Eastman Kodak Company | Fixer additives used in combination with iron complex based bleaches to improve desilvering |
US5508150A (en) * | 1993-12-29 | 1996-04-16 | Eastman Kodak Company | Fixer additives used in combination with iron complex based bleaches to prevent iron retention |
Also Published As
Publication number | Publication date |
---|---|
DE2037684A1 (en) | 1971-02-25 |
CA942559A (en) | 1974-02-26 |
BE754080A (en) | 1971-01-29 |
NL7011234A (en) | 1971-02-02 |
CH511456A (en) | 1971-08-15 |
GB1324515A (en) | 1973-07-25 |
FR2055511A5 (en) | 1971-05-07 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: CIBA-GEIGY AG, SWITZERLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:H.A. WHITTEN & CO.;REEL/FRAME:005184/0184 Effective date: 19890719 |