Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D249/00—Heterocyclic compounds containing five-membered rings having three nitrogen atoms as the only ring hetero atoms
  • C07D249/02—Heterocyclic compounds containing five-membered rings having three nitrogen atoms as the only ring hetero atoms not condensed with other rings
  • C07D249/08—1,2,4-Triazoles; Hydrogenated 1,2,4-triazoles
  • C07D249/10—1,2,4-Triazoles; Hydrogenated 1,2,4-triazoles with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
• • 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
• • 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

• This application describes a bleach-fix bath for use in processing colour photographic material comprising a mild oxidising agent, a silver-halide solvent and a bleachfix accelerator which is a water soluble selenium compound selected from defined classes of selenosemi-carbazides and analogous bis-compounds, 1,2,4-triazole-3- selenols and 5,5-bis, 1,2,4-triazole-3-selen0ls, the invention including the baths per se and their use in colour processing of photographic material.
• a bleach-fix bath for use in processing colour photographic material comprising a mild oxidising agent, a silver-halide solvent and a bleachfix accelerator which is a water soluble selenium compound selected from defined classes of selenosemi-carbazides and analogous bis-compounds, 1,2,4-triazole-3- selenols and 5,5-bis, 1,2,4-triazole-3-selen0ls, the invention including the baths per se and their use in colour
• This invention relates to the processing of photographic material comprising silver halide emulsion layers to yield material having colour dye images therein.
• a developable silver salt image is developed with an aromatic primary amino developing agent of the paraphenylene diamine type (a so-called colour developer) in the presence of a compound (a so-called colour coupler) which will combine with the oxidation products of the colour developer to form an azomethine or quinone-imine dye.
• the dye is thus formed in situ with the developed silver image.
• the product must be treated with a bleach bath and a fixing bath or a combined bleach-fix bath thereby to remove silver and any residual silver halide or other silver salt, leaving in the product only the dye image.
• the photographic material comprises at least one silver halide emulsion layer which includes as a dispersion therein an organic dyestufi of the type which can be destroyed (or bleached) by finely divided silver in a suitable treatment bath.
• the organic dyestutt' is usually an azo dye.
• Most commonly three such silver halide emulsion layers are present each of which is sensitive to a different region of the visible spectrum and each of which contains a difierent azo dye.
• the usual processing sequence for the production of a dye image in the material is after an imagewise exposure to develop the material in a black and white developer. The development is then stopped and the unexposed silver halide is fixed out.
• the material is treated in a dye-bleach bath which oxidises the silver image and simultaneously reduces (bleaches) the dye in the region of the silver image.
• the silver salts and any residual silver must then be removed. This is usually accomplished by washing the material after its treatment in the dye-bleach bath and then treating it in a bleach bath followed by a fixing bath or treating it in a combined bleach-fix bath.
• the photographic material then contains a dye image only; this dye image being usually a direct positive reproduction of the original.
• the amount of residual silver left after the dye-bleach step is not negligible because this material requires to be processed so that the dye-bleach step is terminated before all the image silver has been used in reducing the dye.
• an effective silver bleach step succeeds the dye-bleach step in order to ensure that the residual silver is removed as completely as possible from the material.
• a bleach-fix bath comprises a mild oxidising agent for example a ferric chelate complex, a cupric complex, a salt or a cobalt (III) complex together with a silver halide solvent or fixing agent for example a watersoluble thiosulphate or a water-soluble thiocyanate.
• a mild oxidising agent for example a ferric chelate complex, a cupric complex, a salt or a cobalt (III) complex
• a silver halide solvent or fixing agent for example a watersoluble thiosulphate or a water-soluble thiocyanate.
• Strong oxidising agents cannot be used because they tend to oxidise the silver halide solvent.
• Stable bleach-fix solutions comprising ferric chelate complexes and sodium thiosulphate may be obtained but because of the weak oxidising power of the ferric chelate complex such bleach-fix bath can only be used commercially for the processing of photographic materials with a fairly low silver content.
• a bleach-fix step which comprises treating the photographic material with a stable bleach-fix bath which comprises an aqueous solution of a mild oxidising agent and a silver halide solvent which is either a water-soluble thiosulphate or a water-soluble thiocyanate in the presence of a bleach-fix accelerator which is selected from (a) a water-soluble selenosemicarbazide of the general Formula 1:
• R1 R Se wherein one of R and R is a hydrogen atom or an alkyl, aralkyl or aryl group or a group R CO- where R is a hydrogen atom or an alkyl, alkoxy or heterocyclic group, or a group NR7R3--CSe where R and R are each hydrogen atoms or alkyl groups and the other of R and R is a hydrogen atom or an alkyl group, R is a hydrogen atom or an alkyl, aralkyl or aryl group, one of R and R is a hydrogen atom or an alkyl, aralkyl or aryl group and the other of R and R is a hydrogen atom or an alkyl group but at least one of R R or R being a hydrogen atom and there being not more than one group selected from aryl, aralkyl and heterocyclic present in the compound or (b) a water-soluble compound of the general Formula II:
• each of R R is a hydrogen atom or an alkyl group but there being not more than four alkyl substituent groups in the compound and at least one of R R R R14, R anl R being a hydrogen atom and X is a linkage group wherein m is 0 to 4, or (c) a water-soluble l,2,4-triazole-3-selenol wherein the S-carbon atom carries a substituent selected from a hydrogen atom or an alkyl, hydroxy, amino, alkylamino, arylamino ar aralkylamino group and one of the nitrogen atoms carries a substituent selected from a hydrogen atom or an alkyl, aralkyl or aryl group, or (d) a water-soluble 5,5-bis-1,2,4-triazole-3-sele- 1101 wherein the triazole rings are linked directly or via a link 2)n wherein n is l-4 and wherein one nitrogen atom in each of the triazole
• the preferred compounds for use in the present invention are those of Formula I wherein each of R R are hydrogen atoms or alkyl groups.
• Other preferred compounds are those of Formula II wherein each of *R R is a hydrogen atom.
• the preferred triazole-selenols of (c) are those wherein the S-carbon atom carries an alkyl or hydroxy group and one of the nitrogen atoms carries a substituent hydrogen atom.
• the preferred bis-triazole-selenols of (d) are those wherein one nitrogen atom in each of the triazole rings carries a substituent hydrogen atom.
• stable bleach-fix bath which comprises an aqueous solution of a mild oxidising agent and a silver halide solvent is meant a bleach-fix bath wherein the oxidising agent is strong enough to bleach the silver but is not strong enough to oxidise the silver halide solvent, i.e. the thiocyanate or the thiosulphate, to an appreciable degree.
• the preferred mild oxidising agents for use in the present invention are ferric chelate complexes or diaquo-tetramminecobalt (III) complexes.
• ferric chelate complex is meant a co-ordination compound of the ferric ion and a compound which comprises nitrogen and/or oxygen-containing co-ordinating groups.
• the most important co-ordinating groups are amino, heterocyclic nitrogen, carboxyl and carbonyl groups.
• the preferred ferric chelate complex for use in the bleach-fix step of the present invention is a ferric ethylenediamine-tetraacetic acid complex. It is to be understood that this compound may be used as such in the preparation of a. bleach-fix bath or it may be formed in situ in a bleachfix bath by ethylenediaminetetraacetic acid reacting with a ferric salt e.g. ferric chloride. In the examples which follow the ferric ethylenediaminetetraacetic acid complex has been formed in situ.
• ferric chelate complexes which may be used in the present invention are for example pyridine-2:6-dicarboxylateferrate (III) complex, iminodiacetatoferrate (IH) complex and nitrilo-triacetate-ferrate (III) complex.
• the compounds of Formula II may be prepared by reacting a selenosemicarbazide with a dibasic acid chloride; the reaction usually being carried out in an organic solvent at a low temperature.
• the production of the 1,2,4-triazole-3-selenols of (c) wherein there is attached to the S-carbon atom an alkyl, group comprises reacting a selenosemicarbazide of the general Formula V:
• each of R R and R is a hydrogen atom or two of them are hydrogen atoms and one of them is a group selected from alkyl, aryl and aralkyl, with an acid chloride of the general formula R COCI in the presence of a base or with an acid anhydride of the general formula R COOROR wherein R is an alkyl group and then ring closing this acyl derivative by heating it in the presence of an alkali metal salt of a weak acid for example an acetate or carbonate, or in the presence of an alkali metal hydroxide or an alkoxide.
• the production of the 1,2,4-triazole-3-selenols of (0) wherein there is attached to the S-carbon atom a hydrogen atom or an alkyl group which comprises from 1 to 4 carbon atoms comprises reacting a selenosemicarbazide of the above general Formula V with a carboxylic acid of the general formula R COOH where R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, to form the acyl derivative of the selenosemicarbazide, and then ring closing this acyl derivative by heating it in the presence of an alkali metal salt of a weak acid, for example an acetate or carbonate, or in the presence of an alkali metal hydroxide or an alkoxide.
• a weak acid for example an acetate or carbonate
• the production of the 1,2,4-triazole-3-selenols of (c) wherein there is attached to the S-carbon atom an hydroxy group comprises reacting a selenosemicarbazide of the above Formula V with an alkyloxy-, aryloxyor aralkyloxy-haloformate in the presence of a base to form the alkoxy-, aryloxyor aralkoxycarbonyl derivative of the selenosemicarbazide and ring closing this compound in the presence of an alkali metal salt of a weak acid or in the presence of an alkali metal hydroxide or alkoxide,
• the production of the 1,2,4-triazole-3-selenols of (c) wherein there is attached to the S-carbon atom an amino, alkylamino, arylamino or aralkylamino group comprises reacting a selenosemicarbazide of the general Formula VI:
• Selenosemicarbazides of general Formula VI may be prepared by reacting a bis-selenourea with a one molecular proportion of a methylating agent in a basic medium.
• the production of the bis-1,2,4-triazole-selenols may be effected by reacting a selenosemicarbazide with a dibasic acid chloride in the presence of a base to form the acyl derivative and then ring closing the acyl derivative by heating it in a basic medium e.g. in the presence of an alkali metal carbonate, hydroxide or ethoxide.
• the bleach-fix accelerators of use in the present invention are preferably added to the beach-fix bath but they may be present during the bleach-fixing treatment adsorbed to or absorbed in the colour photographic material.
• bleach-fix accelerators of use in the present invention may be present in any treatment bath or wash bath which is used in the colour development process between the development step and the bleach-fix step. Exemplary of such baths are stop baths and stop-fix baths.
• the bleach-fix accelerators should not be present, however, in the developing solution as they interfere with the development of the colour material. For the same reason the bleach-fix accelerators of use in the present invention should not be present initially in the photographic material.
• the bleach-fix accelerators may be present in the wash bath which succeeds the dye-bleach treatment bath and precedes the bleach-fix bath but the bleach-fix accelerators should not be present during the dye-bleach treatment as they can interfere with this treatment step. Thus the bleachfix accelerators should not be present initially in the silverdye-bleach photographic material.
• a stable-bleach-fix bath which comprises an aqueous solution of a mild oxidising agent, as hereinbefore defined, a silver halide solvent which is either a water-soluble thiosulphate or a water-soluble thiocyanate and a bleach-fix accelerator which is either a selenosemicarbazide of the above Formula I or a compound of the above Formula II, or a 1,2,4-triazole-3-selenol of the type (c) as hereinbefore defined, or a bis-1,2,4- triazole-B-selenol of the type (d) as hereinbefore defined.
• the mild oxidising agent is a ferric chelate complex or a diaquotetrammine-cobalt (III) complex.
• the concentration of the bleach-fix accelerators of the type (a), (b), (c) or (d) as hereinbefore defined present in the bleach-fix bath is greater than 1 mg. per litre of bleach-fix bath. The most preferred amount being mg. of bleach-fix accelerator per litre of bleach-fix bath.
• the concentration of the bleach-fix accelerators of the type (a), (b), (c) or (d) as hereinbefore defined present in a stop bath or a stop-fix bath or in a wash bath is greater than 1 mg. per litre of the solution.
• the blue sensitive layer contained yellow colour coupler of the formula:
• the green sensitive layers each contained a magenta colour coupler of the formula:
• CONDITIONER Disodium salt of ethylene diamine tetraacetic acid g 0.50 Sodium carbonate anhydrous g 4.5 Formaldehyde (40% w./v. solution) ml Lissapol N (8% w./v. solution) ml 1.7 Water to 1 litre.
• Pieces of the colour negative film were fogged and processed in a number of processing sequences all containing the use of a bleach-fix bath.
• the metallic silver remaining in the film at the end of each processing sequence was measured by analysis and expressed in mg. of Ag/decimetre
• the bleach-fix bath or stop-fix bath contained one of the specified bleach-fix accelerators a reduction in the amount of residual silver resulted.
• the residual silver resulting when one of the accelerators was used is expressed as a percentage of that obtained when no accelerator was used (referred to as the control).
• Example 1 Pieces of the colour negative film Were processed as follows:
• Pieces of the colour negative film were processed as follows:
• a positive tripack colour material intended for the silver dye-bleach system comprising silver halide emulsions containing bleachable azo-dyes Cibachrome manufactured by Ciba-Geigy A.G. of Switzerland was given a neutral wedge exposure and processed, the processing sequence being as follows:
• Stop-fix 4 minutes Sodium thiosulphate pentahydrate g 200 Sodium sulphite anhydrous g 20 Water to 1 litre.
• Dye-bleach 20 minutes Sulphuric acid, 96% --ml 27.5 Potassium iodide g 10 Solution of 0.9 g. 2,B-dimethyl-G-aminquinoxaline in 50 ml. ethanol ml Water to 1 litre.
• a stable bleach-fix bath which comprises an aqueous solution of a mild oxidising agent which is strong enough to bleach the silver but not strong enough to oxidise silver halide solvents and a silver halide solvent which is either a water-soluble thiosulphate or a Water-soluble thiocyanate in the presence of a bleach-fix accelerator which is selected from (a) a water-soluble 'selenosemicarbazide of the general formula:
• R and R is a hydrogen atom or an alkyl, aralkyl or aryl group or a group R CO where R is a hydrogen atom or an alkyl, alkoxy or heterocyclic group, or a group NR R CSe- Where R and R are each hydrogen atoms or alkyl groups and the other of R and R is a hydrogen atom or an alkyl group, R is a hydrogen atom or an alkyl, aralkyl or aryl group, one of R and R is a hydrogen atom or an alkyl, aralkyl or aryl group and the other of R and R is a hydrogen atom or an alkyl group, at least one of R R or R being a hydrogen atom and there being not more than one group selected from aryl, aralkyl and heterocyclic present in the compound or (b) a Water-soluble compound of the general formula:
• each of R -R is a hydrogen atom or an alkyl group there being not more than four alkyl substituent groups in the compound and at least one of R R R R14, R and R being a hydrogen atom and X is a -(CH2)m linkage group wherein m is 0 to 4, or (c) a water-soluble 1,2,4-triazole-3-solenol wherein the S-carbon atom car-1 ries a substituent selected from a hydrogen atom or an alkyl, hydroxy, amino, alkylamino, arylamino or aralkylamino group and one of the nitrogen atoms carries a substituent selected from a hydrogen atom or an alkyl, aralkyl or aryl group, or (d) a water-soluble 5,5-bis-1,2,4-tri- 1 1 azolo-3-selenol wherein the triazole rings are linked directly or via a link 2)n' wherein n is 1-4 and wherein one
• bleachfix accelerator is a compound of the formula set forth first in claim 1 wherein each of R R R R and R is a hydrogen atom.
• bleachfix accelerator is a water-soluble 1,2,4-triazole-3 selenol wherein the 5 carbon atom carries a hydrogen atom or an hydroxy group and one of the nitrogen atoms carries a hydrogen atom.
• R is a hydrogen atom or an alkyl, aralkyl or aryl group or a group R CO- wherein R is a hydrogen atom or an alkyl, aralkyl, aryl or heterocyclic group, or
• Ra-C l-86H wherein R is a hydrogen atom or an alkyl group and simultaneously or subsequently treating the photographic material in a stable bleach-fix bath which comprises an aqueous solution of a mild oxidising agent which is strong enough to bleach the silver but not strong enough to oxidise silver halide solvents and a silver halide solvent which is either a water-soluble thiosulphate or a watersoluble thiocyanate.
• ferric chelate complex is a ferric ethylenediaminetetraacetic acid complex.
• a stable bleach-fix bath which comprises an aqueous solution of a mild oxidising agent which is strong enough to bleach the silver but not strong enough to oxidise silver halide solvents, a silver halide solvent which is either a water-soluble thiosulphate or a water-soluble thiocyanate and a bleach-fix accelerator which is selected from (a) a water-soluble selenosementcarbazide of the general formula:
• R3 Se l l NN --N ⁇ R2 R5 wherein one of R and R is a hydrogen atom or an alkyl, aralkyl or aryl group or a group R CO where R is a hydrogen atom or an alkyl, alkoxy or heterocyclic group, or a group NR R -CSe-- where R and R are each hydrogen atoms or alkyl groups and the other of R and R is a hydrogen atom or an alkyl group, R is a hydrogen atom or an alkyl, aralkyl or aryl group, one of R and R is a hydrogen atom or an alkyl, aralkyl or aryl group and the other of R and R is a hydrogen atom or an alkyl group, at least one of R R or R being a hydrogen atom and there being not more than one group selected from aryl, aralkyl and heterocyclic present in the compound or (b) a water-soluble compound of the general formula:
• each of R -R is a hydrogen atom or an alkyl group there being not more than four alkyl substituent groups in the compound and at least one of R R R R R and R being a hydrobgen atom and X is a (CH7) ln' linkage group wherein m is 0 to 4, or (c) a water-soluble 1,2,4-triazole-3-selenol wherein the S-carbon atom carries a substituent selected from a hydrogen atom or an alkyl, hydroxy, amino, alkylamino, arylamino or aralkylarnino group and one of the nitrogen atoms carries a substituent selected from a hydrogen atom or an alkyl, aralkyl or aryl group, or (d) a water-soluble 5,5-bisl,2,4-triazole-3- selenol wherein the triazole rings are linked directly or via a link wherein n is l--4 and wherein one nitrogen atom in each
• a stable bleach-fix bath according to claim 8 wherein the mild oxidising agent is a ferric chelate complex or a diaquotetramine-cobalt (III) complex.
• a stop-fix bath which comprises an aqueous acid solution of a silver-halide solvent selected from a watersoluble thiosulphate and a water-soluble thiocyanate and a water-soluble bleach-fix accelerator which is selected from (a) a water-soluble selenosemicarbazide of the general formula:
• R and R is a hydrogen atom or an alkyl, aralkyl or aryl group or a group R CO- where R is a hydrogen atom or an alkyl, alkoxy or heterocyclic group, or a group NR R -CSewhere R and R are each hydrogen atoms or alkyl groups and the other of R and R is a hydrogen atom or an alkyl group, R 3 is a hydrogengen atom or an alkyl, aralkyl or aryl group, one of R and R is a hydrogen atom or an alkyl, aralkyl or aryl group and the other of R and R is a hydrogen atom or an alkyl group, at least one of R R or R being a hydrgen atom and there being not more than one group selected from aryl, aralkyl and heterocyclic present in the compound or (b) a water-soluble compound of the general formula:
• each of R -R is a hydrogen atom or an alkyl group there being not more than four alkyl substituent groups in the compound and at least one of R R R R R and R being a hydrogen atom and X is a linkage group wherein m is 0 to 4, or (c) a water-soluble 1,2,4-triazole-3-selenol wherein the S-carbon atom carries a substituent selected from a hydrogen atom or an alkyl, hydroxy, amino, alkylamino, arylamino or aralkylamino group and one of the nitrogen atoms carries a substituent selected from a hydrogen atom or an alkyl, aralkyl or aryl group, or (d) a water-soluble 5,5-bis-1,2,4-tri- 13 azole-3-selenol wherein the triazole rings are linked directly or via a link wherein n is 1-4 and wherein one nitrogen atom in each of the triazole rings carries
• a stable bleach-fix bath which comprises an aqueous solution of a mild oxidising agent which is strong enough to bleach the silver but not strong enough to oxidise silver halide solvents and a silver halide solvent which is either a water-soluble thiosulphate or a watersoluble thiocyanate in the presence of a bleach-fix accelerator which is selected from the group consisting of 3-selenosemicarbazide; l-formyl-3-selenosernicarbazide; 1-acetyl-3-selenosemicarbazide; 1-propionyl-3-selenosemicarbazide; 2-methyl-3-selenosemicarbazide; 4-methyl-3-selenosemicarbazide; 1,1'-dimethyl-3-selenosemicarbazide; 1,2-dimethy1-3-selenosemicarbazide; 1,2,4
• a stable bleach-fix bath which comprises an aqueous solution of a mild oxidising agent which is strong enough to bleach the silver but not strong enough to oxidise silver halide solvents, a silver halide solvent which is either a water-soluble thiosulphate or a water-soluble thiocyanate and a bleach-fix accelerator which is selected from the group consisting of 3-selenosemicarbazide; 1-formyl-3-selenosemicarbazide; 1-acetyl-3-selenosemicarbazide; 1-propionyl-3-selenosemicarbazide; 2-methyl-3-selenosemicarbazide; 4-methyl-3-selenosemicarbazide; 1,1'-dimethyl-3-selenosernicarbazide; l,Z-dimethyl-3-selenosernicarbazide; 1,2,4-trimethyl-3-selenosemicarbazide; 1,1',4-trimethyl-3-selenosemicarbazide; 1-acetyl-4-methyl-3-sele

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• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Silver Salt Photography Or Processing Solution Therefor (AREA)

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• 1969
  • 1969-12-23 GB GB6268069A patent/GB1297653A/en not_active Expired
• 1970
  • 1970-12-22 US US100839A patent/US3702248A/en not_active Expired - Lifetime
  • 1970-12-22 SU SU1603518A patent/SU383337A3/ru active
  • 1970-12-23 CA CA101,384A patent/CA968611A/en not_active Expired
  • 1970-12-23 ZA ZA708653A patent/ZA708653B/xx unknown
  • 1970-12-23 JP JP45115907A patent/JPS4834767B1/ja active Pending
  • 1970-12-23 NL NL7018729.A patent/NL166554C/nl not_active IP Right Cessation
  • 1970-12-23 FR FR7046426A patent/FR2074216A5/fr not_active Expired
  • 1970-12-23 CH CH1908770A patent/CH557045A/xx not_active IP Right Cessation
  • 1970-12-23 DE DE2063576A patent/DE2063576C3/de not_active Expired

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