US3895951A - Silver halide emulsion supersensitized with a merocyanine dye and a tertiary phosphine sulfide - Google Patents

Silver halide emulsion supersensitized with a merocyanine dye and a tertiary phosphine sulfide Download PDF

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US3895951A
US3895951A US400238A US40023873A US3895951A US 3895951 A US3895951 A US 3895951A US 400238 A US400238 A US 400238A US 40023873 A US40023873 A US 40023873A US 3895951 A US3895951 A US 3895951A
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silver halide
group
halide emulsion
compound
merocyanines
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US400238A
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Oskar Riester
Hans Ohlschlager
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Agfa Gevaert AG
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Agfa Gevaert AG
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    • 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
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/08—Sensitivity-increasing substances
    • G03C1/28—Sensitivity-increasing substances together with supersensitising substances

Definitions

  • ABSTRACT Photographic silver halide emulsions are spectrally sensitized with neutral methine dyes (merocyanines. including openchain merocyanines and hemioxonoles) and the sensitization is increased and stabilized by the action of phosphine sulfides of the formula wherein R R and R are alkyl, cycloalkyl, aralkyl aryl or heterocyclic groups attached to the phosphorus atom either directly or by connecting members as defined hereinafter.
  • neutral methine dyes merocyanines. including openchain merocyanines and hemioxonoles
  • This invention relates to a light-sensitive photo graphic material containing at least one silver halide emulsion layer which is spectrally sensitized with a merocyanine and the sensitivity of which layer can be substantially increased by the addition of phosphine sulfides.
  • sensitizing action which sensitizing dyes exert on photographic silver halide emulsions can be considereably increased by certain additives which need not themselves be sensitizing dyes.
  • This effect is known as supersensitization.
  • the sensitization achieved in this way is, however, in may cases found to be extremely suspectible to the deleterious action of other necessary additives such as wetting agents, emul sifiers, stabilizers, color couplers or other non sensitizing dyes.
  • This susceptibility to the action of other additives is a particularly serious problem in color photographic materials which contain color couplers or dyes which can be bleached, and it results in insufficient sensitization and in considerable loss of sensitivity in storage under extreme conditions such as high temperature and high atmospheric moisture.
  • Another disadvantage of conventional supersensitization is that the sensitivity to light is in many cases increased only under conditions of low exposure, with the result that the gradation curve as a whole is flattened.
  • This invention thus relates to a light-sensitive photographic material containing at least one silver halide emulsion layer which is spectrally sensitized with a merocyanine.
  • the material is characterised in that the emulsion layer in addition to the merocyanine contains phosphine sulfide of the following formula in which R, and R; which may be the same or different, represent the following groups attached to the phosphorus atom either directly or via a connecting member X,,X as defined hereinafter l. a saturated or unsaturated aliphatic hydrocarbon group. e.g. an alkyl group containing up to car- LII bon atoms, preferably l to 6 carbon atoms, which may be further substituted, e.g.
  • an aryl group such as phenyl or naphthyl, including substituted and condensed aryl groups such as tolyl, xylyl, dodecylphenyl, anisyl, chlorophenyl, dialkylaminophenyl, trifluoromethylphenyl, methylthiophenyl, methylene dioxyphenyl, acetylphenyl, carbalkoxyphenyl, methylsulfonylmethyl, sulfonylphenyl, biphenylyl, tetrahydonapththyl, benzylphenyl, benzothiazol-2-ylphenyl, pyrenyl, chrysenyl or phenylthiophenyl, or 5.
  • aryl group such as phenyl or naphthyl, including substituted and condensed aryl groups such as tolyl, xylyl, dodecylphenyl, anisy
  • heterocyclic group preferably one comprising a 5-, 6- or 7-membered heterocyclic ring which heterocyclic group may also contain condensed benzene rings and may carry further substituents, e.g. a pyrrolidine, piperidine, morpholine, piperazine, hexamethyleneimine, pyridine, thiazole, selenazole, oxazole, imidazole, indole, dihydroindole, pyrimidine, purine, pyrazole, pyrazolone, quinoline, thiadiazole, oxadiazole, triazole, tetrazole, diazine, thiazine, thiadiazine or l,l-dioxothiolan group; R, and R may further together with the phosphorus atom form a phosphorus-containing heterocyclic ring, for example a phospholine ring X, and X which may be the same or different, rep
  • R represents a group as defined under R, and R, that is attached to the phosphorus atom either directly or via a connecting member as defined under X, and X R further may represent a hydroxyl (-OH) or a thiol (SH) group, the latter being presented possibly in anionic form (S), for example as a -SNH., group. R however does not represent a radical bonded to the phosphorus atom via a connecting Oatom, when X, and X, both represent such connecting O- atoms.
  • Any group represented by R if substituted may carry either directly or via one of the connecting members defined above for X, and X and additional group wherein R, and R, have the same meaning as mentioned above.
  • Any heterocyclic group represented by one of R,, R and R may be bonded to the phosphorus atom or to the connecting member either through one of its hetero atoms or through one of its carbon atoms. If there is no connecting member, then the heterocyclic group is prefereably bonded to the phosphorus atom through one of its hetero atoms (generally a nitrogen atom).
  • a pyrrolidyl group is bonded directly to the phosphorus atom preferably through its nitrogen atom thus constituting a P-N bond.
  • the heterocyclic group is bonded to the connecting member preferably through one of its carbon atoms.
  • a carbon atom may be part of the heterocyclic ring or of a benzene ring condensed thereto.
  • a benzothiazole group may be bonded to the connecting member through any of its carbon atoms.
  • the compounds of the above general formula are, from a formal point of view, not all genuine phosphine sulfides but in some cases derivatives (O-esters, S- esters or amides) of the various sulfur analogues of phosphinic acid, phosphonic acid or phosphoric acid, depending on the number of carbon atoms which are indirectly attached to the central phosphorus atom, i.e. by way of a hetero atom.
  • Merocyanines in the context of this application are understood to be neutral cyanine dyes in general as opposed to cationic or anionic cyanine dyes.
  • Merocyanines in this application therefore include not only the merocyanines proper, in which a basic and an acid heterocyclic group are linked together, optionally through an even number of methine groups, but also those merocyanines in which the acid hcterocyclic group (cyclic ketomethylene compound) has been replaced by an open chain ketomethylene compound such as malodinitrile, sulfonylacetonitrile or a-cyanoacetic acid (the so-called open neutrocyanines) as well as those which contain a simple amino group instead of made to Houben-Weyl, Methoden der Organischen Chemie", Georg Thieme Verlag Stuttgart, Vol VII d, 1972. pages 284-295 and to Hamer. Cyanine Dyes and Related Compounds", lnterscience Publishers 1964, pages 485 488 and 511- 61 l.
  • merocyanines and phosphine sulfides may be used in any silver halide emulsions.
  • Suitable silver halides for the emulsions are silver chloride, silver bromide or mixtures thereof, which may have a small silver iodide content of up to mols percent.
  • the silver halides may be dispersed in the usual hydrophilic binders, for example in carboxymethyl' cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, alginic acid and its salts, esters or amides or, preferably, in geiatine.
  • the silver halide emulsions may be the usual negative emulsions or such emulsions useful for forming positive images, for example such emulsions that form latent images predominantly inside the silver halide grains.
  • the phosphine sulfides used according to this invention may be added to the silver halide emulsion at any stage during preparation of the emulsion, for example at the silver halide precipitation stage or latter, e.g. before, during or after chemical ripening. They may be added together with the merocyanines or at an earlier or later stage.
  • the method by which they are added is generally not critical and depends on the solubility properties of the phosphine sulfide used.
  • the usual solvents may also be used for the addition of sensitizing dyes, for example alcohols such as methanol or ethanol, acetone, dimethylformamide, pyrrolidone hydroxypropionitrile, pyridine or phenols, for example cresol, but the compounds may also be added to the emulsion in the form of aqueous dispersions, e.g. dispersions in a dilute gelatine solution. They may also be applied to the emulsion by bathing or immersion or from an adjacent layer.
  • the solvents must, of course, be compatible with gelatine and must not have any deleterious effect on the photographic properties of the emulsion.
  • the quantity of phosphine sulfide added depends on the merocyanine used and on the intensity of the effect desired. Quantities of between 1.5 and 50 X 10 mol per mol of silver halide are generally suitable, the quantities preferably used being 5 to X 10"" mol per mol of silver halide.
  • the quantity of phosphine sulfide used is of much the same order of magnitude as that of the merocyanine, being preferably 1 to times the molar quantity of merocyanine used.
  • the most suitable concentration of phosphine sulfide and merocyanine for any given emulsion can easily be determined by conventional tests employed in the photographic art.
  • the sensitization obtained with the combination according to the invention is substantially unaffected by the presence of color couplers, it is particularly ad vantageous to use such a combination in color photographic materials which contain color couplers.
  • color couplers e.g. cyan couplers based on phenol or naphthol, magenta couplers based on pyrazolone or indazolone and yellow couplers based on open chain ketomethylene compounds.
  • the couplers are hydrophobic couplers that preferably are incorporated in the binder from an organic water immiscible solvent or whether they contaian one or mor watersolubilizing groups, and accordingly may be brought in from aqueous solution.
  • the combination of merocyanines and phosphine sulfides may advantageously also be used in color photographic materials that contain dye-giving compounds for imagewise producing diffusing dyes which can be transferred by diffusion into image receiving layers.
  • the emulsions may also be chemically sensitized, e.g.
  • Certain reducing agents may also be used as chemical sensitizers, e.g. the tin compounds described in Belgian Patent Specifications No. 493,464 and 568,687, polyamines such as diethylene triamine or aminomethylsulfinic acid derivatives, e.g. according to British Patent Specification No. 789,823.
  • Noble metals such as gold, platinum, palladium, iridium, ruthenium and their compounds are also suitable chemical sensitizers. This method of chemical sensitization has been described in the article by R. Koslowsky, Z. Wiss. Phot. 46, 65 72 (1951).
  • the emulsions may also be sensitized with polyalkylene oxide derivatives, e.g. polyethylene oxide with a molecular weight of between 1000 and 20,000, or with condensation products of alkylene oxides and aliphatic alcohols, glycols, cyclic dehydration products and hexitols, alkyl substituted phenols, aliphatic carboxylic acids, aliphatic amines, aliphatic diamines and amides.
  • the condensation products should have a molecular weight of at least 700 and preferably more than 1000. Combinations of these sensitizers may of course also be used in order to achieve special effects, as described in Belgian Patent Specification No. 537,278 and in British Patent Specification No. 727,982.
  • the emulsions may also in addition contain other spectral sensitizers, e.g. the usual monomethine or polymethine dyes such as bacic or acid cyanines, hemicyanines, streptocyanines, oxonoles, styryl dyes, and other that also may have three or more heterocyclic nuclei, such as rhodacyanines and neocyanines.
  • Sensitizers of this type have been described in the work by F. M. Hamer The Cyanine Dyes and Related Compounds" lnterscience Publishers, I964.
  • the emulsions according to the invention may contain the usual stabilizers, e.g. homopolar or ionized compounds of mercury which contain aromatic or herocyclic rings, such as mercurymercaptotriazoles, simple mercury salts and sulphonium mercury double salts.
  • stabilizers e.g. homopolar or ionized compounds of mercury which contain aromatic or herocyclic rings, such as mercurymercaptotriazoles, simple mercury salts and sulphonium mercury double salts.
  • Azaindenes are also suitable stabilizers, especially tetra-or penta-azaindenes and particularly those which are substituted with hydroxyl or amino groups. Such compounds have been described in the article by Birr, Z. Wiss. Phot. 47, 2 58 (1952). Quaternary benzothiazole derivatives, benzotriazole and the like are also suitable stabilizers, among others.
  • the emulsions may also contain white toners such as the known diaminostilbene derivatives as well as socalled masking or sharpening dyes from the series of anthraquinone, triphenylmethane or azo dyes.
  • white toners such as the known diaminostilbene derivatives as well as socalled masking or sharpening dyes from the series of anthraquinone, triphenylmethane or azo dyes.
  • the emulsions may be hardened in the usual manner, for example with formaldehyde or halogenated aldehydes which contain a carboxyl group, such as mucobromic acid, diketones, methane sulphonic acid esters, dialdehydes, dimethylolurea, and dimethylolbenzimidazolone.
  • EXAMPLE 1 A silver halide emulsion which contains per kg l9 g 17 18 of silver, of which 35 mols percent are silver bromide EXAMPLE 2 and 65 mols percent silver chloride, is used. 3 mg of a 10 g of the sodium salt of l hydmxy 4 sulfo merocyamne of the followmg formula dissolved in ace- N octadecy
  • a sensitization maximum in deep red at 702 nm is obtained with this dye.
  • the emulsion is divided into two parts, each of which The samples were developed for 5 minutes at 20C in a developer of the following composition to produce a blue dye image:
  • step wedge Potassium bromide 1 g and an Agfa-Gevaert L 622 red filter (permeable to 2:22 hos hate is light above 622 nm) and developed for 2 minutes at made up with s; mpmoo m1 s 20C in a developer of the following composition:
  • the sensitivities obtained are shown in the folforming coupler) are Show" m Table lowing Table, expressed as number of visible steps T bl 3 ⁇ [7 Table 1 Tropical Fresh Heat conditions Without additive 23 23 23 Tropical w 60 mg of Compound I 27 29 25 Without additive I9 20 22 60 mg of Compound 3 26 28 25 60 mg of Compound 4 26 28 25 60 m of triphenyl- 60 mg of Compound 5 26 27 27 phosphine sul- 150 mg of Compound 6 28 30 27 fide 45 mg of Compound 7 26 27 27 (Compound 1) 24 27 25 45 mg of Compound 8 27 27 27 500 di l d 30 mg of Compound 9 26 28 22 in acetone) in the above Table, fresh means that the material EXAMPLE 4 is proceksfed a few 32 it has been cast heat.
  • Table 7 shows the sensitivity values obtained with and without the addition of mg of triphenylphosphine sulfide (Compound l after exposure behind a step wedge n) and a pale yellow filter which absorbs below 435 nm (GG 435" of Agfa- Gevaert AG) and therefore excludes the intrinsic sensitivity of the emulsion.
  • Example 2 To 1 kg of a silver chlorobromide emulsion as described in Example 1 are added l0 mg of Dye l and 10 of the sodium salt of l-hydroxy-4-sulfo-N-octadecyl-2- naphthamide. To different sample of this emulsion are further added a phosphine sulfide as indicated in the following table 8 in an amount of 60 mg per kg of emulsion. The samples are then cast on a photographic paper base. The dried layer is then exposed to light behind a red filter that is transparent above 622 nm and a a 2 step wedge, and is subsequently color developed. bleach fixed and rinsed. Table 8 shows the sensitivity of the different materials indicated by number of visible steps.
  • a light sensitive photographic material comprising at least one silver halide emulsion layer containing a merocyanine spectral sensitizing agent and a sensitizing and stabilizing tertiary phosphine sulfide having the general formula:
  • R and R may be the same or different and represent a saturated aliphatic hydrocarbon group; a cycloalkyl group; an aralkyl group an aryl group; a heterocyclic group comprising a 6- or 7-membered heterocyclic ring;
  • R represents a saturated or unsaturated aliphatic hydrocarbon group; a cycloalkyl group; an aralkyl group; an aryl group; a heterocyclic group comprising a 5-, 6- or 7-membered heterocyclic ring; a hydroxyl group or a thiol group;
  • X and X, and X represent a chemical bond or linking member containing hetero-atoms and being selected from the group consisting of -O, S, Se, -NR (wherein R stands for hydrogen,

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  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
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  • General Physics & Mathematics (AREA)
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US400238A 1972-09-29 1973-09-24 Silver halide emulsion supersensitized with a merocyanine dye and a tertiary phosphine sulfide Expired - Lifetime US3895951A (en)

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DE19722247893 DE2247893A1 (de) 1972-09-29 1972-09-29 Supersensibilisiertes photographisches material

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JP (1) JPS4973123A (enrdf_load_stackoverflow)
BE (1) BE805129A (enrdf_load_stackoverflow)
DE (1) DE2247893A1 (enrdf_load_stackoverflow)
FR (1) FR2201484B3 (enrdf_load_stackoverflow)
GB (1) GB1436446A (enrdf_load_stackoverflow)
IT (1) IT996212B (enrdf_load_stackoverflow)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4003746A (en) * 1975-07-01 1977-01-18 E. I. Du Pont De Nemours And Company Organic heterocyclic and thioaryl phosphines in silver halide emulsions and developers therefor
US4115129A (en) * 1975-10-01 1978-09-19 E. I. Du Pont De Nemours And Company Organophosphine sulfides as photographic sensitizers
US5378595A (en) * 1993-03-02 1995-01-03 Fuji Photo Film Co., Ltd. Silver halide photo-sensitive material
US5601970A (en) * 1995-01-03 1997-02-11 Eastman Kodak Company Photographic elements exhibiting improved stability
US20050123872A1 (en) * 2003-12-09 2005-06-09 Eastman Kodak Company Method for chemical sensitization of silver halide for photothermographic use
US20050123870A1 (en) * 2003-12-09 2005-06-09 Eastman Kodak Company Photothermographic materials containing silver halide sensitized with combination of compounds
US20050123871A1 (en) * 2003-12-09 2005-06-09 Eastman Kodak Company Method for chemical sensitization of silver halide for photothermographic use

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2271622A (en) * 1940-02-29 1942-02-03 Eastman Kodak Co Photographic emulsion
US3582340A (en) * 1967-07-07 1971-06-01 Konishiroku Photo Ind Process for the antistatic treatment of light-sensitive silver halide photographic materials with phosphine oxide

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2271622A (en) * 1940-02-29 1942-02-03 Eastman Kodak Co Photographic emulsion
US3582340A (en) * 1967-07-07 1971-06-01 Konishiroku Photo Ind Process for the antistatic treatment of light-sensitive silver halide photographic materials with phosphine oxide

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4003746A (en) * 1975-07-01 1977-01-18 E. I. Du Pont De Nemours And Company Organic heterocyclic and thioaryl phosphines in silver halide emulsions and developers therefor
US4115129A (en) * 1975-10-01 1978-09-19 E. I. Du Pont De Nemours And Company Organophosphine sulfides as photographic sensitizers
US5378595A (en) * 1993-03-02 1995-01-03 Fuji Photo Film Co., Ltd. Silver halide photo-sensitive material
US5601970A (en) * 1995-01-03 1997-02-11 Eastman Kodak Company Photographic elements exhibiting improved stability
US20050123872A1 (en) * 2003-12-09 2005-06-09 Eastman Kodak Company Method for chemical sensitization of silver halide for photothermographic use
US20050123870A1 (en) * 2003-12-09 2005-06-09 Eastman Kodak Company Photothermographic materials containing silver halide sensitized with combination of compounds
US20050123871A1 (en) * 2003-12-09 2005-06-09 Eastman Kodak Company Method for chemical sensitization of silver halide for photothermographic use
US7026105B2 (en) * 2003-12-09 2006-04-11 Eastman Kodak Company Photothermographic materials containing silver halide sensitized with combination of compounds
US20060078833A1 (en) * 2003-12-09 2006-04-13 Simpson Sharon M Photothermographic materials containing silver halide sensitized with combination of compounds
US7063941B2 (en) * 2003-12-09 2006-06-20 Eastman Kodak Company Method for chemical sensitization of silver halide for photothermographic use
US7087366B2 (en) * 2003-12-09 2006-08-08 Eastman Kodak Company Method for chemical sensitization of silver halide for photothermographic use
US7157219B2 (en) 2003-12-09 2007-01-02 Eastman Kodak Company Photothermographic materials containing silver halide sensitized with combination of compounds

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JPS4973123A (enrdf_load_stackoverflow) 1974-07-15
BE805129A (nl) 1974-03-21
FR2201484B3 (enrdf_load_stackoverflow) 1976-08-27
DE2247893A1 (de) 1974-04-11
FR2201484A1 (enrdf_load_stackoverflow) 1974-04-26
GB1436446A (en) 1976-05-19
IT996212B (it) 1975-12-10

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