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
  • 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
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D241/00—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings
  • C07D241/36—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings condensed with carbocyclic rings or ring systems
  • C07D241/38—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings condensed with carbocyclic rings or ring systems with only hydrogen or carbon atoms directly attached to the ring nitrogen atoms
  • C07D241/40—Benzopyrazines
  • C07D241/42—Benzopyrazines with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the hetero ring

Definitions

• Z11 A N/ 2 E are used, wherein A, and A each denote a methyl of phenyl residue, E has the significance indicated and D denotes a residue offormula OR, COOR, or
• R represents an alkyl residue with at most five carbon atoms and R, and R each represent a hydrogen atom or an alkyl group with at most five carbon atoms.
• quinoxalines of formula [oHa I A2 and especially of formula are used, wherein A D and E have the indicated significance.
• Quinoxalines which are very suitable correspond to the formula wherein D, denotes an alkoxy group with one to four carbon atoms and E, a hydrogen or halogen atom, an alkyl or alkoxy group with at most 5 carbon atoms, a nitro, amino or alkylamino group with at most four carbon atoms or an acylamino group, and A, and A, nificance.
• D denotes an alkoxy group with one to four carbon atoms and E
• a hydrogen or halogen atom an alkyl or alkoxy group with at most 5 carbon atoms
• a nitro, amino or alkylamino group with at most four carbon atoms or an acylamino group and
• D2 wherein D denotes a methoxy or ethoxy group and E, denotes a chlorine atom or a methyl, methoxy, nitro, amino, methylamino or acylamino group, with acyl representing the residue of an alkanecarboxylic acid with one to five carbon atoms or of an optionally further-substituted benzenecarboxylic acid or heterocyclic carboxylic acid, and E,, A, and A, have the indicated significance, are of special interest.
• Preferred acyl residues in E are residues of alkanecarboxylic acids, for example residues of acetic, propionic or butyric acid or benzenecarboxylic acid residues, for example benzoic acid, toluic acid, chlorobenzoic acid, bromobenzoic acid, nitrobenzoic acid, salicylic acid, methoxybenzoic acid or aminobenzoic acid residues.
• Possible residues of heterocyclic carboxylic acids are for example residues of pyridinecarboxylic, furanecarboxylic and thiophenecarboxylic acids.
• quinoxalines of formula (7) quinoxalines of Q: ICE:
• E denotes a methoxy, methylamino or amino group and D and A, have the indicated significance, again occupy a preferred position.
• R and R each denote an alkyl residue with at most five carbon atoms or a hydrogen atom, and A and A have the indicated significance.
• D represents a residue of formula COOR, wherein R denotes an alkyl residue with at most five carbon atoms or a hydrogen atom, and A and A have the indicated significance.
• the residues D or D and E in formulae (1) to (4), or the residues D,, D E E and E in formulae (5) to 13), can be in the 5-, 6-, 7- or 8-position of the quinoxaline ring system.
• the E and D residues are in the o-position or p-position to one another.
• the quinoxalines of fonnula (1) can be used as dyestuff bleaching catalysts in a processing bath, preferably the dyestuff bleaching bath, and/or in a layer of the photographic material.
• the qunioxalines of formula (1) can also be employed together with other measures which promote bleaching, such as for example together with an irradiation of the dyestuff bleaching bath or bubbling a gas through the dyestuff bleaching bath or adding organic solvents to the dyestuff bleaching bath.
• the quinoxalines of formula (1) can thus be incorporated into a layer which is free of dyestuff which can be bleached image-wise.
• the multi-layer material can thus for example possess an additional gelatine layer containing only the catalyst, this layer being located directly on the layer support or between two colour layers. In the latter case the layer containing the catalyst also acts as a dividing layer.
• the catalyst can also be incorporated into colloidal silver or into filter layers containing an organic yellow filter dyestuff or into coating layers. These filter layers, like the layers with the image dyestuffs, appropriately contain gelatine as the layer colloid.
• the quinoxalines of formula (1) can however also be directly incorporated into a layer containing an image dyestuff.
• the multi-layer material can display the usual composition.
• dyestuff-photographic images can be produced in the usual manner which is in itself known.
• the dyestuff bleaching catalysts of formula (1) can however, as already mentioned, also for example be added to the colour bleaching bath, where they then exert their action directly. They can also be added to a prior treatment bath, for example to the developer, a hardening bath, a stopping bath or a special bath before the silver dyestuff bleaching bath.
• a certain part of the amount of catalyst employed is taken up by the photographic layer material and retained until it can then become effective in the dyestuff bleaching bath.
• the amount of catalyst to be used can vary within wide limits depending on the type of use.
• a dyestuff bleaching bath of the usual composition which contains a silver complex-forming agent such as for example an alkali bromide or iodide or thiourea and optionally an oxidation protection agent such as for example sodium hypophosphite, and a strong organic or inorganic acid, such as for example benzenesulphonic acid, hydrochloric acid, sulphuric acid, phosphoric acid or sodium bisulphate for reaching the requisite pH-value.
• a silver complex-forming agent such as for example an alkali bromide or iodide or thiourea
• an oxidation protection agent such as for example sodium hypophosphite
• a strong organic or inorganic acid such as for example benzenesulphonic acid, hydrochloric acid, sulphuric acid, phosphoric acid or sodium bisulphate for reaching the requisite pH-value.
• a photographic light-sensitive material for the silver dyestuff bleaching process which contains a quinoxaline of formula l as a dyestuff bleaching catalyst in at least one layer on a support, and photographic processing baths, especially dyestuff bleaching baths, characterised in that they contain at least one quinoxaline of formula l as a dyestuff bleaching catalyst.
• a further subject of the invention is then a process for the manufacture of color-photographic images according to the silver dyestuff bleaching process on materials which on a support contain at least one silver halide emulsion layer with a dye-stuff which can be bleached image-wise, by exposure, development of the silver image and dyestuff bleaching, characterised in that the dyestuff bleaching is carried out in the presence of at least one quinoxaline of formula l as the colour bleaching catalyst.
• the hitherto known compounds used as dyestuff bleaching catalysts in the silver colour bleaching process exert very different effects on azo dyestuffs of different constitution. Whilst they are very effective with one class of azo dyestuffs, they can display only a slight bleaching-promoting effect towards another class. There is thus a need for compounds which by themselves or in combination with others effect a uniformly progressing bleaching of all three layer dyestuffs of a multilayer material.
• quinoxalines of formula (I) are outstandingly suitable for this purpose. They are distinguished by an advantageous position of their redox potentials and by good solubility in the requisite concentrations in the dyestuff bleaching bath.
• the quinoxalines of formula (1) used according to the invention especially possess a good activity and effect an advantageous gradation if the residues A, and A in formula (1) each represent a'methyl group; furthermore the bleaching couplings between the individual layers containing the image dyestuffs are largely suppressed when these quinoxalines are present, and given appropriate use.
• the quinoxalines of formula (1 are appropriately manufactured in a manner which is in itself known (compare, in this context, J.C.E. Simpson, Condensed Pyridazine and Pyrazine Rings, in A. Weissberger, The Chemistry of Heterocyclic Compounds, J. Wiley and Sons, New York 1953, 203 et seq.) by condensation of an aromatic l,2-diamine with a l,2-dicarbonyl compound. In place of the diamine, it is also possible to employ the corresponding, significantly more stable, 0-
• nitraniline or the corresponding o-dinitro compound which can be reduced to the desired diamine and then reacted without intermediate isolation to give the quinoxaline.
• Appropriately substituted benzfuroxanes or their reduction products can also be reduced via intermediate stages to l,2-diamines (F.B. Mallory and SP. Varimbi, J. Org. Chem. 28, 1656 et seq. 1963) and the diamines accessible in this way can be condensed to quinoxalines:
• the quinoxalines are obtained in better yield and higher purity if the condensation is carried out under nitrogen.
• a-Oximinoketones can also be reacted with l,2-diamines to give quinoxalines (compare, in this context, .I.C.E. Simpson, loc. cit.).
• Quinoxalinecarboxylic acid esters and amides can be manufactured by means of methods which are in themselves known, via the corresponding acid chloride or the mixed anhydride. In the latter case, the mixed anhydride of the quinoxaline-carboxylic acid and a chlorocarbonic acid ester is advantageously employed.
• the simple esters can also be manufactured by direct esterifrcation.
• nitroalkoxyquinoxalines and the aminoalkoxyquinoxalines are accessible by usual nitration and, where appropriate, reduction of the nitro group. If required, the amino group can be acylated according to known methods.
• N ⁇ Ar D N A2 l,2-Dicarbonyl compounds, a-halogenoketones and a-oximino-ketones Diacetyl, 3-bromobutanone-2, 3-oximinobutanone-2, hexane-dione-3,4, benzil, l-phenylpropanediode-l,2, l-phenyl-2- oximinopropanonel bromopropiophenone, di-(a-naphthyD- diketone and di-(B-naphthyD-diketone.
• o-Nitroanilines or o-dinitrobenzenes and l,2-diamines 3 ,6-Dimethoxyl ,2-dinitrobenzene, 4-methyl-2-nitraniline, 4-methoxy-2-nitraniline, 4-ethoxy-2-nitraniline, 3-ethoxy-2- nitraniline, 2,3-dinitroanisole, 4,5-dinitroveratrole, 4-amino- 3-nitrobenzoic acid, 3-amino-2-nitrobenzoic acid, 2,3- dinitraniline, 3,6-dimethoxy-2-nitraniline, 3,6-dimethoxy-ophenylenediamine, 4-amino-5-nitroveratrole, 4,5- diaminovera-trole, 4methyl-o-phenylenediamine, 4-methoxyo-phenylenedi-amine, 4-ethoxy-o-phenylenediamine, 2- amino-3-nitroanisole, 2-nitro
• Benzfuroxanes 4(7)-chloro-5(6)-methoxybenzfuroxane, 4(7)-chlor-5(6)- ethoxybenzfuroxane, 5(6)-chloro-4(7 )-methoxybenzfuroxane and 5( 6 )-chlor-4( 7 )-ethoxybenzfuroxane.
• Benzfurazanes 4-Chloro-5-methoxybenzfurazane, 4-chlor-5-ethoxybenzfurazane, 4-methoxy-5-chlorobenzfurazane and 4-ethoxy-5- chloro-benzfurazane.
• a substituted o-nitraniline derivative is dissolved, or merely suspended, in a suitable solvent, such as for example methanol, ethanol, glacial acetic acid or dimethylformamide, mixed with l to 10 per cent by weight of hydrogenation catalyst such as for example a 10% strength palladium-charcoal catalyst, and hydrogenated under normal pressure, optionally with initial warming.
• a suitable solvent such as for example methanol, ethanol, glacial acetic acid or dimethylformamide
• hydrogenation catalyst such as for example a 10% strength palladium-charcoal catalyst
• the catalyst is filtered off under N and the filtrate is mixed, under N, with at least the equimolecular amount of distilled or recrystallized diketone or a solution of the diketone in a suitable solvent, whereupon, in most cases, an intensification of colour occurs and the temperature rises.
• the mixture is boiled under reflux until the reaction is complete and the desired substance is isolated after cooling.
• the product can be purified by
• the corresponding 0- dinitro compound is employed in some cases.
• the appropriate o-phenylenediamine is accessible simply and in adequate purity, it is condensed directly, or in the form of its hydrochloride, with the desired diketone in a suitable solvent under nitrogen.
• the hydrochloride it is advisable to add a corresponding amount of sodium or potassium acetate to neutralise the RC1 liberated.
• the adiketone is replaced by a-bromopropiophenone.
• the 1,2-dihydroquinoxaline thus formed is then oxidised with the Na salt of m-nitrobenzenesulphonic acid in the presence of aqueous NaOl-l to give the quinoxaline.
• the redox potentials are determined by means of polarography in the customary manner which is in itself known.
• a mixture of dimethylformamide-2 N sulphuric acid in the ratio of 1 1 serves as the solvent in all cases.
• the potential is measured against an Ag/AgCl electrode of known potential and is then recalculated to the potential against a normal hydrogen electrode. Whilst in some cases two single-electron transitions, characterised in that two polarographic waves occur, are observed, only a single polarographic wave is observed in other cases, and this then corresponds to the mean redox potential.
• the catalyst is filtered off in a closed apparatus under nitrogen and the dark red filtrate is mixed with 4.3 g (50 mmols) ofdiacetyl in a stream of nitrogen.
• the reaction mixture is then heated for 10 minutes under nitrogen to the reflux temperature. After cooling, 300 ml of water are added and the whole is cooled to C.
• the 6-ethoxy-2,3- dimethylquinoxaline which has precipitated is filtered off, washed with a little water and dried at 60 C in vacuo. Yield 7.1 g (70% oftheory) oflight yellow crystals ofthe compound A.
• the thin layer chromatogram with chloroform: ethyl acetate 7:3 as the migrating agent shows a single substance with an Rf-value of 0.57.
• 5-Methoxy-6-chloro-2,3-dimethylquinoxaline 2 g (10 mmols) of 4(7)-methoxy-5(6)-chlorobenzfuroxane are dissolved in 50 ml of ethyl acetate, mixed with 20 mg of platinum oxide and hydrogenated at room temperature under normal pressure. Over the course of 30 minutes, 900 ml of hydrogen are taken up, with the temperature rising to 49 C. After a further minutes the temperature drops back to 25 C; the entire hydrogen uptake is 970 ml (99.5% of theory). The mixture is diluted with 20 ml of acetic acid ethyl ester, warmed to 40 C and filtered in a closed apparatus under nitrogen.
• the filtrate is mixed with 1.72 g (20 mmols) of diacetyl and heated for 45 minutes under reflux. After cooling to room temperature, the mixture is evaporated to dryness and the residue (2.1 g) is recrystallised from water/methanol 1 1. Yield 1.4 g; melting point: 835 to 85 C. Sublimation at 80 C and 0.04 mm Hg finally yields 1.3 g (59% of theory) of almost colourless crystals of the compound C.
• the thin layer chromatogram with trichloromethane as the migrating agent shows a main zone and a slight impurity.
• the thin layer chromatogram in toluene/acetone, 9:1, shows a slight trace of impurity alongside a single product.
• the infrared spectrum shows the characteristic absorptions of the functional groups; the nuclear resonance spectrum is in agreement with the envisaged structure.
• the thin layer chromatogram in toluene/acetone, 9:1 shows slight impurities alongside the main product; the infrared spectrum and the nuclear resonance spectrum are in agreement with the structure.
• pectrum ged structure pectrum ged structure.
• ylic acid amide quinoxaline-o-carboxylic methoxyethane After admine, the mixture is cooled to C. 1.2 g (11 mmols) of chloroformic acid ethyl ester are added dropwise with vigorous stirring in such a way that the Analysis, percent Calculated Found 950 mg (2.75 mmols) of the acid Instruction I are heated for 15 minutes in 15 ml of methanol under reflux, whereupon the colour chan and a yellow precipitate be cooling the product is filtered off, washed with a little icecold methanol and dried in vacuo. The 600 mg of ester thus obtained are recrystallised from 40 ml of methanol.
• the compounds M to RR of Table l are manufactured analogously to the compounds A to L.
• Resldues in Formula (1) 11.5 g mmols) of 5-nitr6-6- oxaline, dissolved in 1 .000 ml of ethanol Raney nickel (activity W 5) and h of hydrogen 100% of theory) are 2 /2 hours. After cooling to room temperature, the catal filtered off and the filtrate is concentrated in vacuo, clarified by filtration with animal charcoal, and finally evaporated to dryness. Yield 6.2 g (62% of theory) of compound G.
• the thin layer chromatogram ,in toluene/acetone, 9:1 shows a slight impurity alongside the main product.
• the in- 10 frared spectrum and the nuclear resonance spectrum are in agreement with the structure of the desired compound.
• 5-Amino-6-ethoxy-2,3-dimethylquinoxaline 5-Amino-6-ethoxy-2,3-dimethylquinoxaline com H) is obtained in 65% yield from 5-nitro-6
• the thin layer chromatogram in toluene/acetone, 9:1 shows a single product and the infrared spectrum and nuclear resonance spectrum correspond to the structure.
• the infrared spectrum shows the bands which are characteristic for acid chlorides. After taking up in 50 ml of chloroform, adding 1 g of animal charcoal, filtering hot and evaporating the filtrate, 2.1 g (78% of theory) of yellowishtinged crystals of melting point 168 to 169 C (decomposition) are obtained.
• the image which has been cleanly bleached colourless is obtained with a distinct stepped gradation of the A solution consisting of 3.3 ml of 6% strength gelatine, 2.0 ml of a 1% ml solution of the hardener 2,4-dichloro-6-phenylamino-l,3,5-triazine-3-sulphonic acid, 0.5 ml of a 2.10 molar solution of compound U in dimethylformamide and 4.2
• Example 2 2 minutes soaking 6. 2 minutes bleaching of the residual silver with a bath containing 150 ml of 37% strength hydrochloric acid, 25 g of copper sulphate and 30 g of potassium bromide per liter the procedure described in Example 1 is followed, a clean positive image of the exposed wedge is again obtained. If, instead of compound U, compound KK is employed as an acetone solution and the procedure of Example 1 is followed, a clean positive image of the wedge used as an original is again obtained.
• the compound U can with equal success be replaced by the compound L, which is applied as an alcoholic solution.
• a photographic material with three color layers contains, on an opaque white cellulose acetate film, a red-sensitive silver bromide emulsion with the blue-green dyestuff of formula on top of this an empty gelatine separating layer, then a greensensitive silver bromide emulsion with the purple dye-stuff of formula 13 l4 (2. 2) NH2 7 H21? O I OH H035 H035 HO- I H 03 S H 03 S After a further separating layer, there follows a layer with a After drying, a grey wedge with clean whites and distinctly yellow filter dyestuff or with colloidal silver acting as a yellow stepped gradation is obtained.
• EXAMPLE 4 40 3. 2 minutes oxidising with a solution of 5 g of potassium bichromate and 5 ml of 96% strength sulphuric acid per Instead of the compound DD as in Example 3, the comliter ofsolution; pound Z or another of the quinoxalines quoted in Table I, dis- 4 minutes oak ng; 7 V g, 7 .solved in a suitable photographically inactive water-miscible 5. 5 minutes washing with a solution of g of anhydrous solvent, can be employed. If the same procedure as in Examsodium sulphite per liter; ple 3 is then followed, then on suitable matching the grey 6. 3 minutes soaking; image of the original used, bleached cleanly to white in the ap- 7.
• Procedure described in example is which contains 150 ml of 37% strength hydrochloric acid, lowed, an Image of the p e g p y bleached to 25 g of copper Sulphate and 30 g of potassium bromide colourless, with contrary gradation, is again obtained.
• the compound U can be replaced by the compound EE, dissolved in methanol. If then the procedure described in this example is followed, a positive image, cleanly bleached to colourless, of the original used is again obtained.
• EXAMPLE 8 A photographic material as described in Example 3 is exposed in the three spectral ranges as indicated in Example 3. The copy is then treated as follows:
• EXAMPLE 9 A solution consisting of 3.3 ml of 6% strength gelatine, 2.0 ml of a 1% strength solution of the hardener described in Example l, 3.3 ml of a silver bromide emulsion which contains 5.3 g of silver per 100 g of emulsion, 0.3 ml ofa 1% strength solution of the blue-green dyestuff of formula 1.1) and 1.1 ml of water is cast onto a glass plate of size 13 cm X 18 cm. After drying, a step wedge is copied onto it (50 Lux, 3 seconds) and the copy is treated as follows:
• Example 2 After 2 minutes soaking the residual silver is oxidised as described in Example 1 under 6) and the material is soaked and fixed as described above. The copy is thoroughly washed and dried. In each case a blue-green wedge, cleanly bleached to colourless, of which the gradation corresponds to that of the original, is obtained.
• EXAMPLE 10 A solution consisting of 3.3 ml of gelatine, 1.0 ml of a 1% strength solution ofthe purple dyestuffofformula 2.0 ml of a 1% strength solution of the hardener described in Example 1, 3.3 ml of a silver bromide emulsion containing 5.3 g of silver per g of emulsion and 0.4 ml of water, is cast onto a glass plate of size 13 cm X 18 cm. After drying, a step wedge is copied thereon (50 Lux, 5 seconds) and the copy is treated as follows:
• a step wedge is copied thereon (50 Lux, 5 seconds) and the material is treated analogously to Examples 9 and 10, with the colour bleaching bath, instead of containing the compounds mentioned there, containing 10 ml of a 4 X 10' molar solution of one of the substances C, D, P, CC, JJ, LL or G6 in m'ethanolor another suitable waterlmiscible photographically inactive solvent.
• Ny A2 as dyestuff bleaching catalyst, in which A and A each is an alkyl radical with at most 5 carbon atoms or a phenyl radical, D is a radical ofthe formula -CN, O-R, COOR or in which R is an alkyl radical with at most five carbon atoms and R, and R, each is a hydrogen atom or an alkyl radical with at most five carbon atoms, and E is a hydrogen or halogen atom, an alkyl or alkoxy group with at most five carbon atoms, a nitro group, an unsubstituted amino group, an alkylammo group with at most four carbon atoms or an acylam no group.
• acyl is the radical of an alkanecarboxylic acid with one to five carbon atoms, benzoic acid, and benzoic acid substituted by halogen, alkyl, nitro, alkoxy, hydroxy or amino and A, and A, each is a methyl or phenyl radical.
• Process according to claim 3 which comprises using a quinoxaline of the formula as a dyestuff bleaching catalyst, in which D is a methoxy or ethoxy group and E is a methoxy, methylamino or amino group.
• R, and R each is an alkyl radical with at most five carbon atoms or a hydrogen atom and A, and A, each is an alkyl radical with at most five carbon atoms or a phenyl radical.
• D is a radical of the formula -COOR, in which R, is an alkyl radical with at most five carbon atoms or a hydrogen atom,and A, is methyl.
• Photographic light-sensitive material for the silver dyestufi bleaching process which contains a quinoxaline of the composition indicated in claim 1 as a dyestuff bleaching catalyst in at least one layer on a support.
• a photographic processing bath for silver dyestuff bleaching material which contains at least a quinoxaline of the composition indicated in claim 1 as a dyestuff bleaching catalyst.

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• 1969
  • 1969-03-13 CH CH382069A patent/CH508226A/de not_active IP Right Cessation
• 1970
  • 1970-03-02 CA CA076173A patent/CA938146A/en not_active Expired
  • 1970-03-03 US US16207A patent/US3656953A/en not_active Expired - Lifetime
  • 1970-03-05 DE DE2010280A patent/DE2010280C3/de not_active Expired
  • 1970-03-10 FR FR7008444A patent/FR2034876A1/fr active Pending
  • 1970-03-12 GB GB02030/70A patent/GB1299402A/en not_active Expired
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  • 1970-03-12 NL NL7003551.A patent/NL167523C/nl not_active IP Right Cessation
  • 1970-03-13 JP JP45021168A patent/JPS4910054B1/ja active Pending

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