EP0573650B1

EP0573650B1 - Silver halide photographic material

Info

Publication number: EP0573650B1
Application number: EP92901465A
Authority: EP
Inventors: Hiroyuki Mifune; Kimiyasu Morimura; Hirotomo Sasaki
Original assignee: Fuji Photo Film Co Ltd
Current assignee: Fujifilm Holdings Corp
Priority date: 1991-12-18
Filing date: 1991-12-18
Publication date: 1999-03-31
Anticipated expiration: 2011-12-18
Also published as: EP0573650A1; EP0573650A4; DE69131075D1; DE69131075T2; WO1993012459A1

Description

Technical Field

The present invention relates to a silver halide photographic light-sensitive material, and more particularly to a silver halide photographic light-sensitive material using a silver halide photographic emulsion whose sensitivity is increased by tellurium sensitization and a cyanine dye.

Background Art

In recent years, it has been increasingly demanded that a silver halide photographic light-sensitive material be provided which has high sensitivity, excellent graininess and great sharpness, and which can also be developed at high speed.
Generally, a silver halide photographic emulsion is spectrally sensitized by using a sensitizing dye, so that it may be photographically sensitive even to those light beams of a wavelength region which silver halide itself does not absorb, such as green light, red light, and infrared rays.
In order to enhance the spectral sensitivity of the emulsion, the amount of the sensitizing dye is increased in many cases. If the amount of the dye is increased, however, the intrinsic desensitization will become prominent. In other words, the emulsion will become less sensitive in the intrinsic wavelength region, probably due to, for example, development inhibition or latent-image dispersion caused by dye, photoelectron deactivation caused by dye holes, or latent-image bleaching. Consequently, the spectral sensitivity of the emulsion can no longer be increased beyond a certain saturated level.
Further, the use of the dye in a great amount results in changes in the sensitivity (a desensitization, in most cases) during the storage of the emulsion. Efforts have been made hitherto in order to render the spectral sensitivity stable and to enhance the same, but the results are not insufficient yet.
A silver halide emulsion for use in silver halide photographic light-sensitive materials is chemically sensitized in most cases, by using various chemicals, in order to have desired sensitivity and gradation.
Among specific methods of chemically sensitizing the emulsion are: reduction sensitization in which a reduction sensitizer is used; noble-metal sensitization in which gold is used; and chalcogen sensitization. These methods can be employed, either singly on in combination. "Chalcogen sensitization" is a general name for sulfur sensitization, selenium sensitization, and tellurium sensitization. Tellurium sensitization is not so known in the art, whereas sulfur sensitization and selenium sensitization have been studied in detail. In fact, tellurium sensitization and tellurium sensitizers are generally described in many publications, such as U.S. Patents 1,623,499, 3,320,069, 3,772,031, 3,531,289, 3,655,394, and 4,704,349, British Patents 235,211, 1,121,496, 1,295,462, 1,396,696, and 2,160,993, Canadian Patent 800,958, and JP-A-61-67845. However, tellurium sensitizers are described specifically and in detail in a few publications only, such as British Patents 1,295,462 and 1,396,696, and Canadian Patent 800,958. Although U.S. Patent 3,655,394, for example, suggests the use of a dye in a tellurium-sensitized emulsion, it does not describe it specifically. The particular advantage resulting from the use of a sensitizing dye, as is practised in this invention, is unknown in the art.
As for the dye used in this invention (represented by the formula (I) later shown) which increases spectral sensitivity, however, causes great intrinsic desensitization if used in a large amount, it has strongly been required that a technique be developed which decreases the intrinsic desensitization and also stably increases the spectral sensitivity.
JP-A-2140736 discloses silver halide photographic materials containing sensitizing cyanine dyes. The emulsions used in these materials further comprise a telluroether compound which is not capable of generating a silver telluride in the emulsion.

Disclosure of the Invention

A first object of the present invention is to provide a silver halide photographic light-sensitive material which has a high spectral sensitivity.
A second object of the invention is to provide a silver halide photographic light-sensitive material which has been greatly spectrally sensitized and whose photographic properties degrade to a very small degree with time during storage.
A third object of this invention is to provide a spectrally sensitized silver halide light-sensitive material which has high sensitivity and is stable, and suitable for high-speed processing.
Accordingly, the present invention provides a silver halide photographic light-sensitive material comprising at least one silver halide emulsion layer on a support, wherein said silver halide emulsion layer contains at least one cyanine dye of formula (I) and a silver halide emulsion subjected to a tellurium sensitization; wherein the tellurium sensitizer used in the tellurium sensitization is a compound which generates silver telluride under any one of the conditions selected from a temperature of 40°C to 95°C, a pH of 3 to 10, and a pAg of 6 to 11 in a silver halide emulsion, and the tellurium sensitization is performed in the presence of at least one tellurium sensitizer which has a pseudo-first order reaction rate constant k for producing silver telluride of 1 x 10^-8 to 1 min^-1;
wherein, Z₁ and Z₂ are the same or different, and represent an atom or group required for forming a heterocyclic ring selected from a thiazoline ring, a thiazole ring, a benzothiazole ring, a naphthothiazole ring, a dihydronaphthothiazole ring, a selenazoline ring, a selenazole ring, a benzoselenazole ring, a naphthoselenazole ring, a dihydronaphthoselenazole ring, an oxazole ring, a benzoxazole ring, a naphthoxazole ring, a pyridine ring, a quinoline ring, a tellurazole ring, a benzotellurazole ring, and a 3,3-dialkylindolenine ring;
R₁ and R₂ are the same or different, being an alkyl group or an alkenyl group, each having 10 or less carbon atoms;
R₃ and R₇ are hydrogen atoms; R₃ and R₁ may combine, and R₇ and R₂ may combine, to form a 5- or 6-membered ring;
R₄, R₅, and R₆ are the same or different, being a hydrogen atom, a C₁-C₈ alkyl group, an aryl group or a ketomethylene residual group;
R₄ and R₆ may combine to form a 5- or 6-membered ring, and if h is 2, R₄ and a different R₄ may combine, and R₅ and a different R₅ may combine, to form a 5- or 6-membered ring;
X is a pairing ion required for neutralizing the electric charge; and j and k are 0 or 1, h is 0, 1 or 2, and m is 0 or 1.
Z₁, Z₂, R₁, R₂, R₄, and R₅ each can be further substituted by substituting groups.
As the examples of the invention will demonstrate, when the emulsion was subjected to tellurium sensitization the intrinsic desensitization due to the dye of the invention was decreased, as a result, the emulsion had a high spectral sensitivity and further its sensitivity changed with time only a little, compared with the well-known sulfur sensitization or selenium sensitization. The result is surprising and not expected.
The compound of the formula (1) will be explained in detail.
The heterocyclic nuclei represented by Z₁ and Z₂ may have one or more substituent groups. Preferred examples of the substituent groups are: a lower alkyl group (which may be branched or further have a substituent group, (e.g., a hydroxy group, a halogen atom, an aryl group, an aryloxy group, an arylthio group, a carboxy group, an alkoxy group, an alkylthio group or an alkoxycarbonyl group}, more preferably an alkyl group having 10 or less carbon atoms in all, such as methyl, ethyl, butyl, chloroethyl, 2,2,3,3-tetrafluoropropyl, hydroxy, benzyl, tolylethyl, phenoxyethyl, phenylthioethyl, carboxypropyl, methoxyethyl, ethylthioethyl or ethoxycarbonylethyl); a lower alkoxy group (which may have a substituent group such as those exemplified as the substituent for the alkyl group, more preferably an alkoxy group having 8 or less carbon atoms in all, e.g., methoxy, ethoxy, pentyloxy, ethoxymethoxy, methylthioethoxy, phenoxyethoxy, hydroxyethoxy or chloropropoxy); a hydroxy group; a halogen atom; a cyano group, an aryl group (for example, phenyl, tolyl, anisyl, chlorophenyl, or carboxyphenyl); and aryloxy group (for example, tolyloxy, anisyloxy, phenoxy, or chlorophenoxy); an arylthio group (for example, tolylthio, chlorophenylthio, or phenylthio); a lower alkylthio group (which may be further substituted by a substituent group such as those exemplified as the substituent for the lower alkyl group, more preferably an alkylthio group having 8 or less carbon atoms in all, e.g., methylthio, ethylthio, hydroxyethylthio, carboxyethylthio, chloroethylthio or benzylthio); an acylamino group (more preferably, an acylamino group having 8 or less carbon atoms in all, such as acetylamino, benzoylamino, methanesulfonylamino or benzensulfonylamino); a carboxy group; a lower alkoxycarbonyl group (more preferably, alkoxycarbonyl having 6 or less carbon atoms in all, such as ethoxycarbonyl or butoxycarbonyl); and an acyl group (more preferably, an acyl group having 8 or less carbon atoms in all, such as acetyl, propionyl, benzoyl or benzenesulfonyl).
R₁ and R₂ can be either identical or different, and each represents an alkyl group or an alkenyl group which has 10 or more carbon atoms in all and which may be substituted. Preferable examples of a substituent group for these alkyl and alkenyl groups are: a sulfo group; a carboxy group; a halogen atom; a hydroxy group; an alkoxy group having 6 or less carbon atoms; an aryl group which has 8 or less carbon atoms and may be substituted (e.g., phenyl, tolyl, sulfophenyl, or caboxyphenyl); a heterocyclic group (e.g., furyl or thienyl); an aryloxy group which has 8 or less carbon atoms and may be substituted (e.g., chlorophenoxy, phenoxy, sulfophenoxy, or hydroxyphenoxy); an acyl group having 8 or less carbon atoms (e.g., benzenesulfonyl, methanesulfonyl, acetyl, or propionyl); an alkoxycarbonyl group having 6 or less carbon atoms (e.g., ethoxycarobynyl or butoxycarbonyl); a cyano group; an alkylthio group having 6 or less carbon atoms (e.g., methylthio or ethylthio); an arylthio group which has 8 or less carbon atoms and may be substituted (e.g., phenylthio or tolylthio); a carbamoyl group which has 8 or less carbon atoms and may be substituted (e.g., carbamoyl or N-ethylcarbamoyl); and an acylamino group having 8 or less carbon atoms (e.g., acetylamino or methanesulfonylamino). R₁ and R₂ may have one or more substituent groups.
Typical examples of the groups represented by R₁ and R₂ are: methyl, ethyl, propyl, ally, pentyl, hexyl, methoxyethyl, ethoxyethyl, phenethyl, tolylethyl, sulfophenethyl, 2,2,2-trifluoroethyl, 2,2,3,3-tetrafluoropropyl, carbamoylethyl, hydroxyethyl, 2-(2-hydroxyethoxy)ethyl, carboxymethyl, carboxyethyl, ethoxycar bonylmethyl. sulfoethyl, 2-chloro-3-sulfopropyl, 3-sulfopropyl, 2-hydroxy-3-sulfopropyl, 3-sulfobutyl, 4-sulfobutyl, 2-(2,3-dihydroxypropyl)ethyl, N-ethylcarbamoylethyl, N-methanesulfonylamylethyl, and 2-(2-(3-sulfopropyloxy)ethoxy)ethyl.
The lower alkyl group and the aryl group, represented by R₄, R₅, and R₆, may be substituted.
Preferably, they have 8 or less carbon atoms in all. Examples of these groups are: methyl, ethyl, propyl, methoxyethyl, phenethyl, phenyl, and tolyl. The ketomethylene residual groups, represented by R₄, R₅, and R₆, are those which have negatively charged and form allopolarcyaine. Examples of these ketomethylene residual groups are: a 1,3-bis(2-methoxyethyl)-1,2,3,4-terahydro-4-oxo-6-oxide-5-pyrimidinyl group and a 1,3-dibutyl-4-oxo-6-oxide-1,2,3,4-tetrahydro-5-pyrimidinyl group.
If X is n pairing anion, it can be a halogen ion, a methyl sulfate ion, an arylsulfonate residual group (e.g., p-toluenesulfonate ion, or 4-methyl-benzensulfonate ion), or a perhalogenate residual group (e.g., perchlorate residual group). If X is a pairing cation, it can be a metal cation (e.g., an alkyl metal cation such as a sodium ion or a potassium ion), ammonium (e.g., trialkylammonium such as triethyleneammonium), or pyridinium.
More preferable as the sensitizing dye represented by the formula (I) is a dye in which Z₁ and Z₂ are atom groups forming a heterocyclic nucleus of benzoxazole, naphthoxazole, benzthiazole, naphthothiazole, dihydronaphthothiazole, benzoselenazole, naphthoselenazole or dihydronapthoselenazole, in which the heterocyclic nuclei represented by Z₁ and Z₂ are unsubstituted or have a substituent group selected from the group consisting of chlorine atom, an alkyl group having 4 or less carbon atoms, an alkoxy group having 4 or less carbon atoms, a phenyl group which has 8 or less carbon atoms and may be further substituted, an acylamino group having 3 or less carbon atoms, an alkoxycarbonyl group having 5 or less carbon atoms, a carboxyl group, and a hydroxy group.
Further, at least one of R₁ and R₂ represents alkyl group or alkenyl group containing a sulfo group, a carboxy group, or a hydroxy group. R₅ or R₆ is preferably, an alkyl group having 4 or less carbon atoms, or R₄ and R₆, R₄ and different R₄ or R₅ and different R₅ is bonded forming a 5- or 6-membered ring.
Preferred examples of X are: a halogen ion such as residual residual group of arylsulfonic acid of p-toluenesulfonic acid, a perhalogeninc acid residual group of perchloric acid. an alkyl metal cation, and a trialkylammonium cation.
In the cyanine dye represented by the formula (I), it is preferable that h is 0, Z₁ and Z₂ represent atoms groups which form the heterocyclic nuclei of benzoxazole, naphthoxazole, benzothiazole or naphthothiazole, R₃ and R₇ represent hydrogen atoms, R₆ represents an ethyl group or a methyl group, at least one of R₁ and R₂ represents an alkyl group containing a sulfo group, a carboxyl group or a hydroxy group. Of these, the most preferable is one in which R₆ represents an ethyl group.
Also preferable compound represented by the formula (I) is one in which, h is 1, Z₁ and Z₂ are atom groups forming the heterocyclic nuclei of benzyoxazole, napthoxazole, benzothiazole, naphthothiazole, benzoselenazole or naphthoselenazole, R₃, R₅ and R₇ represent hydrogen atoms if R₄ and R₆ combine, forming a 5- or 6-membered ring, or R₅ is a lower alkyl group and R₃, R₄ and R₇ represent hydrogen atoms if R₄ and R₆ do not combine to form a ring.
Also preferable compound represented by the formula (I) is one in which, h is 2, Z₁ and Z₂ are atom groups forming the heterocyclic nuclei of benzyoxazole, napthoxazole, benzothiazole, naphthothiazole, benzoselenazole or naphthoselenazole, and R₄ and different R₄, R₅ and different R₅, or R₄ and R₆ are bonded, forming a 5- or 6-membered ring.
Specific examples of the compound of the formula (I) are the following (exemplified compounds).
The compound of the formula (I) can be added in at any step of emulsion preparation; that is at least one step of manufacturing the emulsion, selected from the precipitation of silver halide grains, the physical ripening thereof following the precipitation, the chemical ripening thereof, washing thereof, and the step immediately before the coating of the emulsion. The compound can be added in any desired amount. It is desirable, however, that it is added in an amount of 10^-7 to 10^-2 mol, preferably 10^-6 to 5 × 10^-3 mol, more preferably 10^-5 to 2 × 10^-3 mol, per mol of silver halide, and the amount such that the dye covers 5% to 10% of the surface area of the silver halide grains.
Also, it is desirable that two or more types of the compound represented by the formula (I) be used in combination.
The tellurium sensitizers used in the tellurium sensitization are compounds which form silver telluride in the surface or interior of a silver halide grain, which is considered to function as a sensitization nucleus.
The rate with which silver telluride is formed in the silver halide emulsion can be determined by the following test.
When a tellurium sensitizer is added in a great amount (e.g., 1 × 10^-3 mol/mol Ag), the silver telluride formed absorbs light beam of the visible region. Hence, the method applied for sulfur sensitizers disclosed in E. Moisar, "Journal of Photographic Science," Vol. 14, p. 181 (1966) and ibit., Vol. 16, p. 102 (1968) can be applied. Therefore, the relative rate at which silver telluride is formed can easily be obtained by the same method as used in determining the amount of silver sulfide formed in a silver halide emulsion from the infinite reflectivity of the emulsion to light beams of the visible region (520 nm) in accordance the Kubelka-Munk formula. Since this reaction is apparently similar to a first order reaction, a pseudo-first order reaction rate constant can be obtained, too.
It will be described how to obtain the pseudo-first order reaction rate constant.
An emulsion which contains octahedral silver bromide grains having an average size of 0.5 µm (containing 0.75 mol of AgBr and 80g of gelatin, per kilogram) is maintained at 50°C, while holding pH and pAg at 6.3 and 8.3, respectively. A tellurium compound dissolved in an organic solvent (e.g., methanol) is added to the emulsion, in an amount of 1 × 10^-3 mol/mol Ag. The resultant emulsion is filled in a cell having a thickness of 1 cm. Then, the reflectivity (R) change of the emulsion to light beams of 520 nm with the passage the time is detected by means of a spectrophotometer having an integrating sphere, using the reflectivity of a blank emulsion as reference. Reflectivity, thus detected, is substituted in the Kubelka-Munk formula, (1-R)²/2R. The time when the value of (1-R)²/2R becomes 0.01 is measured. The pseudo-first order reaction rate constant k (min^-1) is determined from the time thus measured. If no silver telluride is formed at all, R = 1, and the Kubelka-Munk value is 0 as in the case where no telluride is present. Preferable is a compound which is found to have a apparent pseudo-first order reaction constant of 1 × 10^-8 to 1 × 10⁰ min^-1 when tested in exactly the same way as described above. The pseudo-first order reaction rate constants of the tellurium sensitizers of the present invention, which have been obtained by performing the test described above, are as follows: Compound 7* ≃ 4 × 10-3 min-1 Compound 10* ≃ 2 × 10-3 min-1 Compound 12* ≃ 8 × 10-4 min-1 Compound 18* ≃ 2 × 10-4 min-1 Compound 4* ≃ 7 × 10-5 min-1 *: The number assigned to the compounds exemplified tellurium sensitizers, which will be specified later.
In the case where a tellurium sensitizer is added in so small an amount that the absorption of light beam of the visible region can hardly be detected, the silver telluride formed can be separate from the unreacted tellurium sensitizer, to determine the quantity of the silver telluride. For instance, the immersion in an aqueous solution of a halogen salt or a water-soluble mercapto compound, thereby separating, and then a small amount of Te is quantitatively analyzed by means of atomic absorption spectrometry. The reaction rate greatly varies by seveal orders, in accordance with not only the type of the compound but also the silver halide composition of the emulsion tested, the test temperature and the values of aAg and pH. The tellurium sensitizers preferred for use in the present invention are compounds which can form silver telluride when reacted with a specific silver halide emulsion which has halide composition and crystal habit to be used. Generally speaking, any compound is used in the range 40 to 95°C, at a pH value of 3 to 10, or at a pAg value of 6 to 11. More preferable as a tellurium sensitizer is a compound which has a pseudo-first order reaction rate constant k of 1 × 10^-7 to 1 × 10^-1 min^-1 if tested by the method specified above at 40 to 95°C, at a pH value of 3 to 10, or at a pAg value of 6 to 11.
Tellurium sensitizers preferred for use in the present invention are, for example, the compounds which are described in U.S. Patents 1,623,499, 3,320,069 and 3,772,031, British Patents 235,211, 1,121,496, 1,295,462 and 1,396,696, Canadian Patent 800,958, Journal of Chemical Society Communication 635 (1980), ibid. 1102 (1979), ibid. (197D), and Journal of Chemical Society Perkin Transaction 1, 2191 (1908).
Specific examples of the tellurium sensitizers are: colloidal tellurium, telluroureas (e.g., allyl-tellurourea, N,N-dimethyltellurourea, tetramethyl tellurourea, N-carboxyethyl-N',N'-dimethyltellurourea, N,N'-dimethylethylene tellurourea, and N,N'-diphenylethylene tellurourea), isotellurocyanates (e.g., allylisotellurocyanate), telluroketones (e.g., telluroacetone and telluroaceto phenone), telluroamides (e.g., telluroacetoamide and N,N-dimethyl tellrobenziamide), tellurohydrazides (e.g., N.N',N'-trimethyltellurobenzhydrazide), telluroester (e.g., t-butyl-t-hexyltelluroester), phosphinetellurides (e.g., tributylphosphinetelluride, tricyclohexylphosphinetelluride, triisopropyl phosphinetelluride, butyl-diisopropylphosphinetelluride, and dibutylphenylphosphinetelluride), and other tellurium compounds (e.g., gelatin containing negatively charged telluride ions, disclosed in British Patent 1,295,462, potassium telluride, potassium tellurocyanate, telluropentathionate sodium salt, and allyltellurocyanate).
Of the tellurium compounds specified above, those represented by the following formula (II) or (III) are preferred:
In the formula (II), R₁₁, R₁₂ and R₁₃ are an aliphatic group, an aromatic group, a heterocyclic group, OR₁₄, NR₁₅(R₁₆), SR₁₇, OSiR₁₈(R₁₉)(R₂₀) a halogenatom or a hydrogen atom; R₁₄ and R₁₇ represent an aliphatic group, an aromatic group, a heterocyclic group, a hydrogen atom or a cation; R₁₅ and R₁₆ represent an aliphatic group, an aromatic group, a heterocyclic group or a hydrogen atom, and R₁₈, R₁₉ and R₂₀ are an aliphatic group.
The formula (II) will now be explained in detail.
The aliphatic groups represented by R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, R₁₆, R₁₇, R₁₈, R₁₉, and R₂₀ in the formula (I) are preferably those having 1 to 30 carbon atoms. Particularly preferable are alkyl group, alkenyl group, alkynyl group, and aralkyl group, each having 1 to 20 carbon atoms and present in the form of a straight chain, a branch, or a ring. Examples of alkyl group, alkenyl group, alkynyl group and aralkyl group are: methyl, ethyl, n-propyl, isopropyl, t-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopentyl, cyclohexyl, allyl, butenyl, 3-pentenyl, propargyl, 3-pentynyl, benzyl, and phenethyl.
The aromatic groups represented by R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, R₁₆ and R₁₇ in the formula (II) are preferably those having 6 to 30 carbon atoms. Particularly preferred is aryl group having 6 to 20 carbon atoms and present in the form of a single ring or a condensed ring, such as phenyl or naphthyl.
The heterocyclic groups identified by R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, R₁₆ and R₁₇ in the formula (I) are saturated or unsaturated 3- to 10-membered heterocyclic groups, each having at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom. They can form a single ring, or can combine with an aromatic ring or another heterocyclic ring, thus forming a condensed ring. Preferable are 5- or 6-membered aromatic heterocyclic group such as pyridyl, furyl, thienyl, thiazolyl, imidazolyl, and benzimidazolyl.
The cations represented by R14 and R17 in the formula (II) are, for example, alkali metal or ammonium.
The halogen atom in the formula (I) is, for example, a fluorine atom, a chlorine atom, a bromine atom, or a iodine atom.
The aliphatic groups, the aromatic groups, and the heterocyclic groups, all specified above, can be substituted.
Typical examples of the substituent groups are: an alkyl group, an aralkyl group, an alkenyl group, an alkeynl group an aryl group, an alkoxy group an aryloxy group, an amino group, an acylamino group, an ureido group, an urethane group, a sulfonylamino group, a sulfamoyl group, a carbamoyl group, a sulfonyl group, a sulfinyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an acyl group, an acyloxy group, a phosphoric acid amido group, a diacylamino group, an imido group, an alkylthio group, an arylthio group, a halogen atom, a cyano group, a sulfo group, a carboxyl group, a hydroxyl group, a phosphono group, a nitro group, and a heterocyclic group. These groups may be further substituted.
If two or more substituent groups are used, they may be identical or different.
R₁₁, R₁₂, and R₁₃ may combine together and with phosphor atoms, forming a ring. R₁₅ and R₁₆ may combine thus forming a nitrogen-containing heterocyclic ring.
In the formula (II), R₁₁, R₁₂, and R₁₃ are preferably ferably aliphatic groups or aromatic groups. More they are alkyl groups or aromatic groups.
In the formula (III), R₂₁ is aliphatic group, aromatic group, heterocyclic group or -NR₂₃(R₂₄); R₂₂ is -NR₂₅(R₂₆), -N(R₂₇) N(R₂₈)R₂₉ or -OR₃₀;
R₂₃, R₂₄, R₂₅, R₂₆, R₂₇, R₂₈, R₂₉ and R₃₀ are hydrogen atoms, aliphatic groups, aromatic groups, heterocyclic groups or acyl groups; R₂₁ and R₂₅, R₂₁ and R₂₇, R₂₁ and R₂₈, R₂₁ and R₃₀, R₂₃ and R₂₅, R₂₃ and R₂₇, R₂₃ and R₂₈, and R₂₃ and R₃₀ may combine, forming a ring.
The general formula (III) will be explained in detail.
The aliphatic groups represented by R₂₃, R₂₄, R₂₅, R₂₆, R₂₇, R₂₈, R₂₉ and R₃₀ in the formula (III) are preferably those having 1 to 30 carbon atoms. Particularly preferable are alkyl group, alkenyl group, alkynyl group, and aralkyl group, each having 1 to 20 carbon atoms and present in the form of a straight chain, a branched chain, or a ring. Examples of alkyl group, alkenyl group, alkynyl group and aralkyl group are: methyl, ethyl, n-propyl, isopropyl, t-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopentyl, cyclohexyl, allyl, 2-butenyl, 3-pentenyl, propargyl, 3-pentynyl, benzyl, and phenethyl.
The aromatic groups represented by R₂₁, R₂₃, R₂₄, R₂₅, R₂₆, R₂₇, R₂₈, R₂₉ and R₃₀ in the formula (III) are preferably those having 6 to 30 carbon atoms. Particularly preferred is aryl group having 6 to 20 carbon atoms and present in the form of a single ring or a condensed ring, such as phenyl group or naphthyl group.
The heterocyclic groups identified by R₂₁, R₂₃, R₂₄, R₂₅, R₂₆, R₂₇, R₂₈, R₂₉ and R₃₀ in the formula (III) are saturated or unsaturated 3- to 10-membered heterocyclic groups, each having at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom. They can be each a single ring, or can combine with an aromatic ring or another heterocyclic ring, thus forming a condensed ring. Preferable are 5- or 6-membered aromatic heterocyclic group such as pyridyl, furyl, thienyl, thiazolyl, imidazolyl, and benzimidazolyl.
It is desirable that the acyl groups identified by R₂₃, R₂₄, R₂₅, R₂₆, R₂₇, R₂₈, R₂₉ and R₃₀ shown in the formula (III) have 1 to 30 carbon atoms. More preferably. they are acyl groups having 1 to 20 carbon atoms and present in the form of a straight chain or a branched chain. Examples of these acyl groups are acetyl, benzoyl, formyl, pivaloyl, and decanoyl.
In the case where R₂₁ and R₂₅, R₂₁ and R₂₇, R₂₁ and R₂₈, R₂₁ and R₃₀, R₂₃ and R₂₅, R₂₃ and R₂₇, R₂₃ and R₂₈, and R₂₃ and R₃₀ combine, forming a ring, the ring is, for example, an alkylene group, an allylene group, an aralkylen or an alkenylene group.
The aliphatic groups, the aromatic groups, and the heterocyclic groups, described above, can be substituted by the substituent groups specified in the general formula (II).
In the formula (III), R₂₁ is preferably aliphatic group, aromatic group, or -NR₂₃(R₂₄), and R₂₂ is-NR₂₅(R₂₆). R₂₃, R₂₄, R₂₅ and R₂₆ are aliphatic groups or aromatic groups.
More preferably, in the formula (II), R₂₁ is aromatic group or -NR₂₃(R₂₄), R₂₂ is -NR₂₅(R₂₆), and R₂₃, R₂₄, R₂₅ and R₂₆ are alkyl groups or aromatic groups. It is also preferably that, R₂₁ and R₂₅, and R₂₃ and R₂₅ are attached to each other through alkylene group allylene group, aralkylene group, or alkenylene group, thereby forming a ring.
Specific examples of the compounds represented by the formulas (II) and (III) are as follows. Nonetheless, the compounds used in the invention are not limited to these specified below. II - 1. (nC₄H₉)₃P = Te II - 2. (tC₄H₉)₃P = Te
II - 4. ((i)C₃H₇)₃P = Te

II - 7. ((i)C₄H₉)₃P = Te

II - 15. (n-C₄H₉O)₃P = Te
The compounds used in the invention, represented by the formulas (II) and (III), can be synthesized by the methods already known, such as those disclosed in journal of Chemical Society (A), 2927 (1969), Journal of Organometallic Chemistry, 4,320 (1965), ibid, 1,200 (1963), ibit, 113, C35 (1976), Phosphorus Sulfur 15, 155 (1983), Chemische Berichte, 109, 2996 (1976), Journal of Chemical Society Chemical Communication, 635 (1980), ibid, 1102 (1979), ibid, 645 (1979), ibid, 820 (1987), Journal of Chemical Society Perkin Transaction 1,2191 (1980), The Chemistry of Organo Selenium and TEllurium Compounds, Vol. 2, pp. 216 267 (1987).
The amount in which tellurium sensitizers in the present invention is used depends on, for example, the type of silver halide grains used and the conditions of chemical sensitization performed. Generally, however, it is 10^-8 to 10^-2 mol, preferably 10^-7 to 5 × 10^-3 mol per mol of silver halide.
There is no limitation to the conditions in which to effect chemical sensitization in the present invention. However, it is desirable that the silver halide grains be chemically sensitized at a pAg value of 6 to 11, preferably 7 to 10 and at temperature of 40 to 95°C, preferably 45 to 85°C.
The present invention relates not only to a silver halide photographic light-sensitive material, but also to a tellurium-sensitized silver halide emulsion and the use of tellurium sensitization. Its indispensable element is a cyanine dye represented by the formula (I) shown above. Namely, the emulsion according to this invention is a tellurium-sensitized silver halide emulsion which contains contains at least one cyanine dye represented by the formula (I). The use of tellurium sensitization of the invention is use of tellurium sensitization to reduce intrinsic desensitization of the silver halide emulsion which is caused by said at least one cyanine dye.
Noble-metal sensitizers using gold, platinum, palladium and iridium, are preferably used in the present invention, too. In particular, a gold sensitizer is preferably used. Specific examples of gold sensitizers are: chloroauric acid, potassium chloroaurate, potassium auric thiocyanate, gold sulfide and gold selenide. These sensitizers can be used in an amount of 10^-7 to 10^-2 mol per mol of silver halide.
In this invention, it is also preferable to use sulfur sensitizers. Specific examples of the sulfur sensitizers are labile sulfur compounds such as thiosulfates (e.g., hypo), thioureas (e.g., diphenylthiourea, triethylurea, and allylthiourea) and rhodanines which can be used. These sulfur compounds can he used in an amount of 10^-7 to 10^-2 mol per silver halide.
It is also desirable that selenium sensitizers be used, in the present invention.
For example, the labile selenium sensitizer disclosed in JP-B-44-15748 is preferably used. ("JP-B" means Published Examined Japanese Patent Application).
Specific examples of selenium sensitizers are: colloidal selenium, selenoureas (e.g., N.N-dimethyl selenourea, selenourea, tetramethyl selenourea), selenoamides (e.g., selenoacetoamide, N,N-dimeyhylselenobenzemide), selenoketones (e.g., slenoacetone, selenobenzophenone), selenides (e.g., triphenyl phosphineselenide, diethylselenide), selenophosphates (e.g., tri-p-trylselenophosphate), selenocarboxylic acid, esters, and isoselenocyanates. These selenium sensitizers can be used in an amount of 10^-8 to 10^-3 mol per mol of silver halide.
In the present invention, a reduction sensitizer can be also used. Specific examples of the reduction sensitizer are: stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivative, borane compound (e.g., dimethyulamineborane), silane compound, and polyamine compound.
Preferably, tellurium sensitization is carried out in this invention, in the presence of a solvent for dissolving the silver halide.
Specific examples of this solvent are: thiocyanate (e.g., potassium thiocyanate), thioether compound (e.g., the compounds disclosed in U.S. Patents 3,021,215 and 3,271,157, JP-B-58-30571, and JP-A-60-136736 ("JP-A-" means Published Unexamined Japanese Patent Application), for example, 3,6-dithia-1,8-octanediol), and tetra-substituted thiourea compound (e.g., the compounds disclosed in JP-B-59-11892 and U.S. Patent 4,221,863, particularly tetramethyl thiourea). Other examples of the solvent are: the thione compounds disclosed in JP-B-60-11341, the mercapto compounds disclosed in JP-B-63029727, the mesoion compounds disclosed in JP-A-60 163042, the selenoether compounds disclosed in U.S. Patent 4,782,013, the telluoether compounds disclosed in JP-A-2-118566, and sulfides. Of these examples, thiocyanate, thioether compendious, tetra-substituted thiourea compounds, and thione compounds are preferred. The solvent can be used in an amount of 10^-5 to 10^-2 mol per mol of silver halide.
The silver halide emulsion according to the invention and the silver halide emulsion which can he used in the same or different layer, along with the emulsion of the present invention, (hereinafter called "emulsion which can be used in the invention") are preferably silver bromide, silver bromochloride, silver bromoiodide, silver bromochloroiodide, silver chloroide.
The silver halide grains which can be used in the present invention are those having a regulur crystal shape, as cubic ones or octahedral ones, those having an irregular crystal shape, such as spherical ones and tabular ones, or those having a complex shape, i.e., a combination of these crystal shapes. A mixture of silver halide grains having various crystal shapes can be used. Nonetheless, it is desirable that silver grains having a regular crystal shape be used.
The silver halide grains which can be used in this invention can have different a phases in the internal portion and in the surface portion, or have a uniform phase. Double-structured or multi-structured grains are also preferable, the internal and surface portions of which have different iodine compositions (particularly, those the internal portions of which contain more iodine). Also, grains forming an latent image mainly on their surface (for example, negative-type emulsion) can be used. Alternatively, grains forming an latent image mainly in their internal portions (for example, internally latent emulsion or a fogged direct reversal type emulsion) can be used. Preferable are grains forming a latent image mainly on their surface.
Preferable as silver halide emulsion which can be used in the invention is the emulsion which contains tabular grains. Preferably, the tabular-grain emulsion contains grains having a thickness of 0·5 µm (0.5 microns) or less, preferably 0·3 µm (0.3 microns) or less, and a diameter of 0·6 µm (0.6 microns) or more, and in the emulsion the grains having an aspect ratio of 3 or more occupy 50% or more of the total projected area of all grains.
Particularly preferable as silver halide emulsion which can be used in this invention is a monodisperse emulsion which has a statistical variation coefficient of 30% or less, preferably 20% or less. (The variation coefficient is the value of S/d, where d is the average diameter of the grains, and S is the standard deviation of the distribution in terms of the diameter of a circle having the same area as the projected area of a grain.)
The photographic emulsion which can be used in the present invention can be prepared by methods described in, for example, P. Glafkides, "Chimie et Phisique Photographique," Paul Montel, 1967; G.F. Duffin. "Photographic Emulsion Chemistry," Focal Press, 1966; and V.L. Zelikman et al., "Making and Coating Photographic Emulsion," Focal Press, 1964.
A solvent for silver halide can be used to control the growth of silver halide grains during the forming of the grains. Examples of such solvents are: ammonia; potassium rhodanide; ammonium rhodanide; thioether compounds (e.g., those disclosed in U.S. Patents 3,271,157, 3,574,628, 3,704,130, 4,297,439, and 4,276,374); and amine compounds (e.g., the compound disclosed in JP-A-54-100717).
The silver halide grains may be formed or physically ripened in the presence of cadmium salt, zinc salt, thallium salt, iridium salt, a complex salt thereof, rhodium salt, a complex salt thereof, iron salt, or a complex salt thereof.
Gelatin is useful as a binder or a protective colloid which can be used in the emulsion or interlayer of the light-sensitive material according to the present invention. Other hydrophilic colloids can be used. Examples of other hydrophilic colloid are: proteins such as gelatin derivetives, graft polymer of gelatin and high-molecular substance, albumin, and casein; cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose, and cellulose sulfate ester; sugar derivatives such as sodium arginate and starch derivative; and synthetic hydrophilic high-molecular substances such as homopolymer or copolymer of e.g., polyvinyl alcohol, polyvinyl alcohol partial acetal, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole and polyvinylpyrazole.
Gelatin can not only be lime-treated gelatin, but also acid-treated gelatin or such an enzyme-treated gelatin as is disclosed in Bull. Soc. Sci. Photo. Japan, No. 16, p. 30 (1966). Also, a substance obtained by hydrolyzing gelatin or by decomposing gelatin with an enzyme.
In the light-sensitive material of the present invention, an inorganic or organic film hardener may be contained in a hydrophilic colloid layer constituting a light-sensitive layer or a back layer. Examples of the film hardener are: chromium salt, aldehyde salt (e.g., formaldehyde, glyoxal, glutaraldehyde); and N-methylol-based compound (e.g., dimethylolurea). Active halogen compound (e.g., 2,4-dichloro-6-hydroxy-1,3,5-triazine and the sodium salt thereof); and active vinyl compounds (e.g., 1,3-bisvinylsulfonyl-2-propanol, 1,2-bis(vinylsulfonylacetoamido)ethane, bis(vinylsulfonyl methyl)ether, and a vinyl-based polymer having a vinylsufonyl group as a side chain) are preferred since they fast harden hydrophilic colloid such as gelatin, imparting stable photographic properties. N-carbamoylpyridium salts (e.g., 1-morpholinocarbonyl-3-pyridinio)methanesulfonate) or haloamidium salts (e.g., 1-(1-chloro-1-pyridinomethylene)pyrrolidium-2-naphthalenesulfonate excel in hardening speed.
The silver halide photographic emulsion which can be used in the invention may be be spectrally sensitized with methine dyes different from the dye represented by the formula (I). Examples of the dyes are: cyanine dye, merocyanine dye, composite cyanine dye, composite merocyanine dye, holopolar cyanine dye, hemicyanine dye, styryl dye, and hemioxonol dye. Of these dyes, particularly useful are a dye belonging to a cyanine dye, a merocyanine dye, and composite merocyanine dyes. These dyes contains nuclei which are usually used in cyanine dyes as basic heterocyclic nuclei. Examples of the nuclei are nuclei such as a pyrroline nucleus, an oxazoline nucleus, a thiazoline nucleus, a pyrrole nucleus, an oxazole nucleus, a thiazole nucleus, a selenazole nucleus, an imidazole nucleus, a teterazole nucleus, and a pyridine nucleus; nuclei obtained by fusing an aliphatic hydrocarbon ring to any one of these nuclei; and nuclei obtained by fusing an aromatic hydrocarbon ring to any one of these nuclei, such as an indolenine nucleus, a benzindolenine nucleus, an indole nucleus, a benzioxadole nucleus, a naphthoxazole nucleus, a benzothiazole nucleus, a naphthothiazole nucleus, a benzoselenazole nucleus, a benzimidazole nucleus, and a quinoline nucleus. These nuclei can be substituted at carbon atoms.
Merocyanine dye or composite merocyanine dye can be one which has nuclei of ketomethylene structure. Applicable as such nuclei are 5- or 6-membered heterocyclic nuclei of pyrazoline-5-one, thiohydantoin, 2-thiooxazolidine 2,4-dione, thiazolidine-2.4-dione, rhodanine or thiobarbituric acid.
These sensitizing dyes can be used, either singly or in combination. In many cases, they are used in combination, for achieving supersensitization. The emulsion may contain not only the sensitizing dye, but also a dye which has no spectral sensitizing ability or a substance which absorbs virtually no visible light and has supersensitizing ability. Examples of such a dye or such a substance are: aminostilbene compounds (e.g., those disclosed in U.S. Patents 2,933,390 and 3,635,721); formaldehyde condensstes of aromatic organic acid (e.g., the condensate disclosed in U.S. Patent 3,743,510); cadmium compounds; and azaindene compounds. The combinations of disclosed in U.S. Patent 3,615,613 3,615,641, 3,617,295, and 3,635,721 are particularly useful.
The photographic emulsion used in the invention can contain various compounds to prevent fogging from occurring during the manufacture, storage or processing of the light-sensitive material, or to stabilize the photographic properties of the light-sensitive material. More precisely, compounds known as antifoggants and stabilizing agents can be added to the emulsion. Examples of these compounds are: azoles such as benzothiazolum salt, nitroindazoles, nitrobenzimidazoles, chicobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, aminotriazoles, benzotriazoles, nitrobenzotriazoles, mercaptotetrazoles (particularly, 1-phenyl-5-mercaptotetrazole); mercaptopyrlmidines; mercaptotriazines; thioketo compounds such as oxadolinethione; azaindenes such as triazaindene and tetrazaindene (particularly, 4-hydroxy-subutituted (1, 3, 3a, 7) tetraazaindenes), and pentaazaindenes; benzenethiosulfonic acid; benzensulfinic acid; benzensulfonicamide.
It is desirable that the silver halide emulsion of the invention be used in a green-sensitive emulsion layer, a red-sensitive emulsion layer, or an infrared-sensitive emulsion layer. The emulsion can be used in two or more emulsion layers, if any, which are sensitive to the same color and which have different sensitivities. The emulsions of the invention can be used in the form of a mixture, if necessary. Also, it is possible to use the emulsion of the invention, together with an emulsion which falls outside the scope of the present invention. To attain the advantage of the invention, it is desirable that the emulsion of the invention is used in an amount of 30 mol% or more, preferably 50 mol% or more in the same emulsion layer.
An emulsion falling outside the scope of the invention can be selected, for use together with the silver halide emulsion of the invention, in accordance with its halogen composition, its grain size and its crystal habit, in the same way as the emulsion of the present invention. Also, the method for preparation and spectral sensitization of the emulsion can be selected in the same way as the emulsion of the present invention.
The light-sensitive material according to this invention may contain a coating aid and one or more surfactants for various purposes, e.g., for improving the antistatic property and slipping property of the material, for promoting emulsification and dispersion, for preventing the material from adhering to other things, and for improving the photographic properties of the material (e.g., developing acceleration, high contrast, and sensitization).
The hydrophilic colloid layer of the light-sensitive material made by the present invention may contain a water-soluble dye used as filter dye or as a substance for preventing irradiation or halation and for other various purposes. As the water-soluble dye, an oxonol dye, a hemioxonol dye, a styryl dye, a merocyanine dye, anthraquinone dye, and an azo dye can be preferably used. A cyanine dye, an azomethine dye, a triarylmethane dye, and a phthalocyanine dye are useful, too. Also, an oil-soluble dye can be emulsified by means of oil-in-water dispersion and then be added to the hydrophilic colloid layer.
The present invention can be applied to a multilayered color photographic material which has at least two emulsion layers having different spectral sensitivities and formed on a support.
Generally, a multilayered silver halide color photographic light-sensitive material have at least one red-sensitive emulsion layer, at least one green-sensitive emulsion layer, and at least one blue-sensitive emulsion layer -- all formed on a support. The order in which these layers are arranged can be arbitraly selected as need. Preferably, the red sensitive layer, the green-sensitive layer, and the blue-sensitive layer are arranged in this order from the support; the blue-sensitive layer, the green-sensitive layer, and the red-sensitive layer are arranged in this order from the support; or the blue-sensitive layer, the red-sensitive layer, and the green-sensitive layer are arranged in this order from the support. Any layer sensitive to a specific color can be formed of two or more emulsion layers having different sensitivities, so that it may have a higher sensitivity. Further, it can be formed of three layers to have its graininess improved. A non-light-sensitive layer may be present between at least two emulsion layers having the same color sensitivity. Also, an emulsion layer sensitive to a color may be interposed between two emulsion layers sensitive to another color. Moreover, a reflecting layer formed of fine silver halide grains may be provided beneath a high-sensitivity layer, particularly a high blue-sensitive layer, thereby to increase the sensitivity of the light-sensitive material.
Generally, a red-sensitive emulsion layer contains a cyan-forming coupler, a green-sensitive emulsion layer contains a magenta-forming coupler, and a blue-sensitive emulsion layer contains a yellow forming coupler. A different combination of couplers can be adopted in some cases. For instance, an infrared-sensitive layer can be combined with other layers, thus forming a light-sensitive material for pseudo-color photography or semiconductor-laser exposure process.
Various color couplers can be used in the photographic light-sensitive material of the present invention. Specific examples of these couplers are described in patents described in above-mentioned Re search Disclosure (RD), No. 17643, VII-C to VII-G.
Preferable examples of a yellow coupler are described in, e.g., U.S. Patents 3,933,501, 4,022,620, 4,326,024, and 4,401,752, JP-B-58-10739, British Patents 1,425,020 and 1,476,760.
Examples of a magenta coupler are preferably 5-pyrazolone and pyrazoloazole compounds, and preferable examples are the compounds described in, e.g., U.S. Patents 4,310,619 and 4,351,897, European Patent 73,636, U.S. Patents 3,061,432 and 3,725,067, Research Disclosure No. 24220 (June 1984), JP-A-60-33552, Research Disclosure No. 24230 (June 1984), JP-A-60-43659, U.S. Patents 4.500.630 and 4,540,654.
Examples of a cyan coupler are phenol and naphthol couplers. Of these, preferable are those descrihed in, for example, U.S. Patents 4,052,212, 4,146,396, 4,228,233, 4,296,200, 2,369,929, 2,801,171, 2,772,162, 2,895,826, 3,772,002, 3,758,308, 4,343,011, and 4,327,173, West German Laid-open Patent Application 3,329,729, European Patent 121,365A, U.S. Patents 3,446,622, 4,333,999, 4,451,559 and 4,427,767, and European Patent 161,626A.
Preferable examples of a colored coupler for correcting additional, undesirable absorption of a colored dye are those described in, for example, Research Disclosure No. 17643, VII-G, U.S. Patent 4,163,670, JP-B-57-39413, U.S. Patents 4,004,929 and 4,138,258, and British Patent 1,146,368.
Preferable examples of a coupler capable of forming colored dyes having proper diffusibility are those described in, for example, U.S. Patent 4,366,237, British Patent 2,125,570, European Patent 96,570, and West German Laid-open Patent Application No. 3,234,533.
Typical examples of a polymerized dye-forming coupler are described in U.S. Patents 3,451,820, 4,080,211 and 4,367,282, and British Patent 2,102,173, and the like.
Couplers releasing a photographically useful residual group upon coupling can be preferably used in the present invention. Preferable as DIR couplers releasing a development inhibitor are those described in the patents cited in the above-described RD No. 17643, VII-F, JP-A-57-151944, and U.S. Patent 4,248,962.
Preferable examples of a coupler for imagewise releasing a nucleating agent or a development accelerator at the time of development are described in, for example, British Patents 2,097,140 and 2,131,188, JP-A-59-157638, and JP-A-59-170840.
Examples of other couplers which can be used in the light-sensitive material of the present invention are competing couplers described in, for example, U.S. Patent 4,130,427; poly-equivalent couplers described in, for example. U.S. Patents 4,283,472, 4,338,393, and 4,310,618; a DIR redox compound releasing coupler or a DIR coupler releasing coupler disclosed in JP-A-60-185950 and JP-A-62-24252, and the like; couplers releasing a dye which turns to a colored form after being released described in European Patent 173302A; a bleach accelerator releasing coupler disclosed in RD No. 11449, RD No. 24241, JP-A-61-201247, and the like; and a ligand releasing coupler described in, e.g., U.S. Patent 4,553,477 and the like.
The couplers for use in this invention can be added to the light-sensitive material by various known dispersion methods.
Examples of a high-boiling organic solvent to be used in the oil-in-water dispersion method are described in U.S. Patent 2,322,027 and the like.
Examples of a high-boiling organic solvent to be used in the oil-in-water dispersion method and having a boiling point of 175°C or more at atmospheric pressure are phthalate esters (e.g., dibutylphthalate, dicyclo hexylphthalate, di-2-ethylhexylphthalate, decylphtha late, bis(2,4-di-t-amylphenyl) phthalate, bis(2,4-di-t-amylphenyl) isophthalate, bis(1,1-di-ethylpropyl) phthalate); phosphate or phosphonate esters (e.g., triphenylphosphate, tricresylphosphate, 2-ethylhexyl diphenylphosphate, tricyclohexylphosphate, tri-2-ethyl hexylphosphate, tridodecylphosphate, tributoxyethyl phosphate, trichloropropylphosphate, and di-2-ethyl hexylphenylphosphonate); benzontes (e.g., 2-ethylhexylbenzoate; dodecylbenzoate, and 2-ethylhexyl-p-hydroxybenzoate); amides (e.g., N,N-diethyldodecane amide, N,N-diethyllaurylamide, and N-tetradecylpyrrolidone); alcohols or phenols (e.g., isostearylalcohol and 2,4-di-tert-amylphenol), aliphatic carboxylates (e.g., bis(2-ethylhexyl) sebacate, dioctylazelate, glyceroltributylate, isostearyllactate, and trioctyl citrate); aniline derivative (e.g., N,N-dibutyl-2-butoxy-5-tert-octylaniline); and hydrocarhons (e.g., paraffin, dodecylbenzene, and diisopropylnaphthalene). An organic solvent having a boiling point of 30°C or more and preferably, 50°C to 160°C can be used as an auxiliary solvent. Typical examples of the auxiliary solvent are ethyl acetate, butyl acetate, ethyl propionate, methylethylketone, cyclohexanone, 2-ethoxyethylacetate, dimethylformamylketone, cyclohexanone, 2-ethoxyethylacetate, and dimethylformamide.
Steps and effects of a latex dispersion method and examples of a loadable latex are described in, e.g., U.S. Patent 4,199,363 and German Applications (OLS) 2,541,274 and 2,541,230.
In the photographic light-sensitive material, the photographic emulsion layers and the other layers are coated on a flexible support such as a plastic film, a sheet of paper or a piece of fabric, which is usually used, or on a rigid support made of glass, ceramics or metal. Useful as a flexible support are a film made of a semi-synthetic or synthetic high-molecular compound such as cellulose nirate, cellulose acetate, cellulose acetate butyrate, polystyrene, polyvinyl chloride, polyethylenetephthalate or polycarbonate; and a sheet of paper laminated with a baryta layer or coated with α-olefin polymer (for example, polyethylene, polypropyrene, or ethylene/buten copolymer). The support may be colored with a dye or a pigment. It can be black to shield light. These supports are undercoated in most cases, so that they may be well adhered to photographic emulsion layers. Glow discharge, corona discharge, ultraviolet rays, or flames can be applied to the surfaces of the support before or after the support is undercoated.
Photographic emulsion layers and the other hydrophilic colloid layers can be coated by means of various known methods, such as dip coating, roller coating, curtain coating, and extrusion coating. If necessary, a plurality of layers may be coated simultaneously by the coating methods disclosed in, for example, U.S. Patents 2,681,294, 2,761,791, 3,526,528, 3,508,947.
The present invention can be applied to various color light-sensitive materials and various monochrome light-sensitive materials. Typical examples of the materials are a color negative film for a general purpose or a movie, a color reversal film for a slide or a television, color paper, a color positive film, color reversal paper, color-diffusion transfer light-sensitive materials, and thermally developing color light-sensitive materials. The present invention can also be applied to a monochrome light-sensitive material for use in X-ray photography, by utilizing the tricolor-coupler mixture described in Research Disclosure No. 17123 (July 1978), and the like, or by using the black-coloring coupler disclosed in U.S. Patent 4,126,461, or British Patent 2,102,136. Also, the present invention can be applied to printing-plate film such as lithographic film or scanner film, X-ray film for direct and indirect medical use or industrial use, negative monochrome film for photography, monochrome printing paper, microfilm for COM use or ordinary use, light-sensitive material of silver-salt diffusing transfer type, and light-sensitive material of print-out type.
To apply the photographic element used in the present invention to color-diffusion transfer photographic method, it can be a film unit of peel-apart type, integrated type (like those disclosed in JP-B-46-16356, JP-B-48-33697, JP-A-50-13040, and British Patent 1,330,524), or peel-free type (like those disclosed in JP-B-57-119345).
In any type of the format described above, it is desirable to use a polymer acid layer protected by a neutralization-timing layer, in order to broaden the range of the processing temperature. To apply the photographic element to color-diffusion transfer photographic method, too, it can be added to any layer of the light-sensitive material or can be sealed in a processing solution vessel as a component of the developing solution.
Various exposing means can be used for the light-sensitive materials according to the present invention. An arbitrary light source for emitting radiation corresponding to a sensitivity wavelength of a light-sensitive material can he used as an illumination light source or a write light source. Natural light (sunbeam), an incandescent lamp, a halogen atom-sealed lamp, a mercury lamp, a fluorescent lamp, or a flash light source (for example, an electronic flash or a metal combustion flash bulb) can be generally used.
A gas, dye solution, or semiconductor laser, a light-emitting diode, or a plasma light source for emitting light ranging from an ultraviolet range to an infrared range can be used as a recording light source. In addition, an exposing means as a combination of a linear or surface light source with a fluorescent screen (for example, a CRT) for emitting light upon excitation of fluorescent substances by electron beams, a liquid crystal (LCD), or a microshatter array utilizing lanthanum-doped lead-titanium zirconate (PLZT) can be used. The spectral distribution used in exposure can adjusted by a color filter, as needed.
The color developing solution for used in developing the light-sensitive material of the present invention is preferably an alkaline, water-soluble solution the main component of which is aromatic primary amine-based color developing agent. Aminophenol-based compounds are useful as this color developing agent, but p-phenylenediamine-based compounds are preferably used. Typical examples of p-phenylenediamine-series compounds are: 3-methyl-4-amino-N,N-diethylaniline, 3-methyl-4-amino-N-ethyl-N-β-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-β-methanesulfonamidoethylaniline, 3-methyl-4-amino-N-ethyl-N-β-methoxyethylaniline, and sulfates, hydrochlorides and p-toluenesulfonates thereof. Generally, these diamines are more stable in the form of salts than in the isolated form, and are preferably used.
In general, the color developing solution contains a pH buffering agent such as a carbonate, borate, or phosphate of an alkali metal, and a development restrainer or an antifoggant such as a chloride, a bromide, an iodide, a benzimidazole, a benzothiazole, or a mercapto compound. If necessary, the color developer may also contain a preservative such as hydroxylamine or sulfite; an organic solvent such as triethanolamine or ethyleneglycol; a development accelerator such as benzylalcohol, polyethyleneglycol, a quaternary ammonium salt or an amine; a dye-forming coupler; a competing coupler; a nucleus-forming agent such as sodium boron hydride; an auxiliary developing agent such as l-phenyl-3-pyrazolidone; a viscosity-imparting agent; a chelating agent such as aminopolycarboxylic acid, aminopolyphosphonic acid, alkylphosphonic acid, or phosphonocarboxylic acid; and an anti-oxidation agent such as those disclosed in West German Patent Application (OLS) 2,622,950.
In the development of a reversal color light-sensitive material, black-and-white development is performed and then color development is performed. As a black-and-white developing solution, well-known black-and-white developing agents, e.g., dihydroxybenzenes such as hydroquinone, 3-pyrazolidones such as 1-phenyl-3-pyrazolidone, and aminophenols such as N-methyl-p-aminophenol can be used, either singly or in a combination of two or more thereof.
Photographic emulsion layers, which have been color-developed, are usually bleached. The bleaching may be carried out simultaneously with, or independently of, fixing process. In order to process the layers at a high speed, the layers may be bleach-fixed after they have been bleached. As bleaching agent, use can be made of compounds of polyvalent metals, such as iron(III), cobalt(III) and chromium(III) and copper(II), peroxides, quinones, nitroso compounds, and the like. Typical examples of the bleaching agent are: ferricyanide; bischromate; an organic complex salt of iron(III) or cobalt(III), such as complex salt of aminopolycarboxylic acid (e.g., ethylenediaminetetraacetic acid, diethylenetriaminepentaacettic acid, nitrilotriacetic acid, or 1,3-diamino-2-propanol tetraacetic acid), citric acid, tartaric acid or malic acid; persulfate; manganate; and nitrosophenol. Of these bleaching agents, ethylenediaminepentaacetic iron(III) salt, diethylenetriaminetetraacetic iron(III) slat, and persulfate are preferred for high-speed processing and in view of environmental pollution. Iron(III) complex salt of ethylenediamine tetraacetic acid is useful, not only in an independent bleaching solution, but also in a single beach-fixing solution.
A bleaching accelerator can be used in the bleaching solution, the bleach-fixing solution, and their pre-bath, if necessary. Useful examples of the bleaching accelerator are: compounds having a mercapto group or a disulfide group described in, e.g., U.S. Patent 3,893,858, West German Patents 1,290,812 and 2,059,988, JP-A-53-32736, JP-A-53-57831, JP-A-53-37418, JP-A-53-72623, JP-A-53-95630, JP-A-53-95631, JP-A-53-104232, JP-A-53-124424, and JP-A-53-141623, and JP-A-53-28426, and Research Disclosure No. 17,129 (July, 1978); a thiazolidine derivative described in JP-A-50-140129; thiourea derivatives described in JP-B-45-8506, JP-A-52-20832, JP-A-53-32735, and U.S. Patent 3,706,561; iodide salts described in West German Patent 1,127,715 and JP-A-58-16235; polyoxyethylene oxide compounds descried in West German Patents 966,410 and 2,748,430; a poly amine compound described in JP-B-45-8836; compounds descried in JP-A-49-40943, JP-A-49-59644, JP-A-53-94927, JP-A-54-35727, JP-A-55-26506, and JP-A-58-163940; and an iodide and a bromide ion. Of these compounds, a compound having a mercapto group or a disulfide group is preferable since the compound has a large accelerating effect. In particular, compounds described in U.S. Patent 3,893,858, West German Patent 1,290,812, and JP-A-53-95630 are preferred. A compound described in U.S. Patent 4,552,834 is also preferable. These bleaching accelerators may be added in the light-sensitive material. These bleaching accelerators are useful especially in bleach-fixing of a photographic color light-sensitive material.
Examples of the fixing solution are thiosulfate, a thiocyanate, a thioether-based compound, a thiourea and a large amount of an iodide. Of these compounds, thiosulfate is generally used. Preferable as bleach-fixing solution and preservative for the fixing solution are: a sulfite, bisulfite, or a carbonyl bisulfite adduct.
Generally, a water-washing process and a stabilizing process are performed after the bleach-fixing process or the fixing process. In the water-washing process and the stabilizing process, various known compounds may be added for the purpose of preventing precipitation or saving water. To prevent precipitation, for example, there may be added, if necessary, a water-softening agent such as inorganic phosphoric acid, aminopolycarboxylic acid, organic aminopolyphosphonic acid, or organic phosphoric acid; a bactericide or a fungicide preventing generation of various bacteria, duckweed, or mildew; a metal salt the typical examples of which are magnesium salt, aluminum salt, and bismuth salt; a surfactant for preventing a drying load or a non-uniform drying; and various hardeners. Alternatively, compounds of the tape disclosed in L.E. West, "Photographic Science and Engineering," Vol. 6, pp. 344-359 (1965) and the like may be added. The addition of cheleting agents and fungicides is particularly effective.
To save water, the water-washing process is conducted, usually in a counter-current scheme, using two or more tank. Such a multi-stage counter-current stabilizing process as is described in JP-A-57-8543 may be performed instead of the water-washing process. In this process, 2 to 9 tanks for counter-current baths are required. Various compounds are added to the stabilizing baths for purpose of stabilizing images, in addition to the additives mentioned above. For example, various buffering agents (e.g., borate, methaborate, borax, phosphate, carbonate, potassium hydroxide, sodium hydroxide, ammonia water, monocarboxylic acid, dicarboxylic acid, polycarboxylic acid, and the like, used in combination), or an aldehyde such as formaling for the purpose of adjusting film pH. If necessary, various additives such as a cheleting agent (e.g., inorganic phosphoric acid, aminocarboxylic acid, organic phosphoric acid, organic phosphonic acid, aminopolyphosphonic acid, or phosphonocarboxylic acid), a bactericide (e.g., benzoisothiazolinone, isothiazolone, 4-thiazolinebenzimidazole, halogenated phenol, sulfanilamide, or benzotriazole), a surfactant, a fluorescent brighter, and a hardener can be used. Two or more compounds serving the same purpose or different purposes may be used in combination.
Various ammonium salts are preferably used. Examples of the ammonium salts are: ammonium chloride, ammonium nitrate, ammonium sulfate, ammonium phosphate, ammonium sulfite, and ammonium thiosulfate as film-pH adjusting agent after the film is processed.
In processing a color light-sensitive material for photography use, the (water-washing and stabilizing) processes conducted in most cases after the fixing process may be replaced by a stabilizing process and a water-washing process (a water-saving process). In this case, the formalin in the stabilizing bath can be eliminated if 2-equivalent magenta coupler is used.
In the present invention, the water-washing and stabilizing processes are carried out, usually for 20 seconds to 10 minutes, preferably 20 seconds to 5 minutes, depending on the type of the light-sensitive material and the processing conditions.
The silver halide color light-sensitive material of the present invention may contain a color developing agent in order to simplify processing and increases a processing speed. For this purpose, various types of precursors of a color developing agent can be preferably used.
Examples of the precursor are an indoaniline-based compound described in U.S. Patent 3,342,597, Schiff base compounds described in U.S. Patent 3,342,599 and Research Disclosure (RD) Nos. 14,850 and 15,159, an aldol compound described in RD No. 13,924, a metal salt complex described in U.S. Patent 3,719,492, and an urethane-based compound described in JP-A-53-135628. Other examples of the precursor are various salt-type ones disclosed in, for example, JP-A-56-6235, JF-A-56-16133, JP-1-56-59232, JP-A-56-67842, JP-A-56-83734, JP-A-56-83735, JP-A-56-83736, JP-A-56-89735, JP-a-56-81837, JP-A56-54430, JP-A-56-106241, JP-56-107236, JP-A-57-97531, an JP-A-57-83565.
The silver halide color light-sensitive material of the present invention may contain various 1-phenyl-3-pyrazolidones in order to accelerate color development, if necessary. Typical examples of the compound are described in, for example, JP-A-56-64339, JP-A-57-144547, JP-A-57-211147, JP-A-58-50532, J-P-a-58-50536, JP-A-58-50533, JP-A58-0532, JP-A58-50535, and JP-A-58-115438.
Various processing solutions used in the present invention are used at a temperature of 10°C to 50°C. Although a normal processing temperature is 33°C to 38°C, processing may be accelerated at a higher temperature to shorten a processing time, or image quality or stability of a processing solution may be improved at a lower temperature. In order to save silver, a process may be conducted which makes use of the cobalt intensification or the hydrogen peroxide intensitication described in West German Patent 2,226,770 and U.S. Patent 3,674,499.
If required, a heater, a temperature sensor, a liquid-level sensor, a circulation pump, a filter, a floating cover, or a squeegee may be provided in the processing baths.
To achieve a continuous processing, replenishers of various processing solutions are used, thereby preventing changes in the compositions of the solutions, thereby obtaining constant finish. The amount of each replenisher can be reduced to half or less the standard amount of the replenisher, in order to reduce the cost of the processing.
If the light-sensitive material of this invention is color paper, it may be bleach-fixed in most cases. If it is a color photographic material, it may be bleach-fixed if necessary.

Mode of Carrying out the Invention

The present invention will be described in more detail below by way of its examples. The numbers assigned to the compounds (i.e., cyanine dyes and tellurium sensitizers) used in each example, which will be described, are the numbers allocated to the compounds already exemplified above.

EXAMPLE 1

A silver nitrate aqueous solution (AgNO₃, 18g) and a potassium bromide aqueous solution (KBr. 12.7g) were added over 20 minutes to 1 liter of a pH 5.0 aqueous solution containing 0.35g of potassium bromide and 40g of gelatin, while this solution was being maintained at 75°C and being stirred. A silver nitrate aqueous solution (AgNO₃, 156g) and a mixture aqueous solution of potassium iodide and potassium bromide (6.1g + 196g/liter) were added simultaneously over 20 minutes by flow rate accelerating method, in which the final flow rate was increased to 5.4 times the initial flow rate. During this addition, the silver potential was held at -25 mV with respect to the saturated calomel electrode.
After the forming of grains, the solution was desalted by ordinary flocculation and then washed with water. Next, gelatin and water were added, adjusting pH and pAg to 6.3 and 8.3, respectively. The silver bromoiodide emulsion, thus obtained, was a monodisperse octahedral emulsion containing about 2 mol% of silver iodide and having a grain diameter of 0.49 µm and a variation coefficient of 9.5% in terms of grain diameter.
This emulsion was divided into four parts. Then, 1.2 × 10^-5 mol/mol Ag of a sulfur sensitizer (S), sodium thiosulfate was added (EmA); 0.9 × 10^-5 mol/mol Ag of a selenium sensitizer (Se), N,N-dimethylselenourea was added (EmB); 3.6 × 10^-5 mol/mol Ag of a tellurium sensitizer (Te), II-12 was added (EmC); and 1.2 × 10^-4 mol/mol Ag of a tellurium sensitizer (Te), colloidal tellurium prepared by the method disclosed in Canadian Patent 800,958 was added (EmC'). These four parts of emulsion were ripened for 60 minutes, thereby preparing four emulsions EmA, EmB, EmC, and EmC'.
Each of emulsions EmA, EmB, EmC, and EmC' was divided into parts. To these parts, there were Added 3.2 × 10^-4 mol/mol Ag of the cyanine dye (I-11) used in this invention, gelatin, 4-hydroxy-6-methyl-1,3,3a,7-tetraazaindene, potassium polystyrenesulfonate, and sodium dodecylbenzenesulfonate. Each resultant emulsion was coated on an undercoated triacetylcelluose film support, simultaneously with a protective layer containing gelatin, polymethylmethacrylate grains, and 2,4-dichloro-6-hydroxy-s-triazine sodium salt, by means of simultaneous extrusion method.
The samples were subjected to sensitometry exposure (1/100 second) through an optical wedge using a 419 nm interfering filter for measuring the intrinsic sensitivity of the silver halide, and filter SC-50 manufactured by Fuji Film for measuring the spectral sensitivity, developed at 20°C for 10 minutes with Kodack developing solution D-19, and then stopped, fixed, water-washed, and dried in ordinary method. The densities of the samples, thus processed, were measured.
The relative sensitivity of each sample is represented in the relative value of a reciprocal of the exposure amount required to impart an optical density of fog +0.2. In the intrinsic sensitivity, the relative sensitivity of Sample 1 was defined as 100 and in the spectral sensitivity, the relative sensitivity of Sample 5 was defined as 100.
As is evident from Table 1, the tellurium sensitization provided higher sensitivity than the sulfur sensitization, but was somewhat inferior to the selenium sensitization, when no dye was used.
When the dye used in the invention was added, however, the tellurium sensitization achieved a surprising advantage, that is, it imparted spectral sensitivity far higher not only than did the sulfur sensitization, but also than did the selenium sensitization.
This is because of the surprising result that, as may be understood from the measured intrinsic sensitivities, the tellurium sensitization involved a far smaller decrease of intrinsic sensitivity due to the dye, than the sulfur sensitization or the selenium sensitization.
Although colloidal tellurium, hitherto known as a tellurium sensitizer, helped to achieve the advantage of the invention, the compound of the formula (II), according to the present invention, was more preferable.

EXAMPLE 2

Emulsions EmA(S), EmB(Se), and EmC(Te) were prepared in the same way as in Example 1. Each emulsion was divided into parts. The cyanine dyes specified in Table 2 were added to these parts. Using the resultant emulsions, Samples 10 to 33 were prepared in the same way as in example 1.
SC-50 filter was used for Samples 10 - 27 and SC-60 filter was used for Samples 28 - 33 and the same developing process as in Example 1 was performed. The spectral sensitivity of each sample was represent, such that the relative value of emulsion EmA was defined as 100.
As is clearly seen from Table 2, the tellurium sensitization imparted a higher spectral sensitivity than the sulfur sensitization or the selenium sensitization, whichever cyanine dye was used.

EXAMPLE 3

Samples 1 to 3 of Example 1, and Samples 19 to 21 and 31 to 33 of Example 2 were left to stand for 3 months, and were exposed and developed in the same way as in Examples 1 and 2. The intrinsic sensitivity of each samples thus processed, was measured. The results were as is shown in the following Table 3, along with the values (Tables 1 and 2) measured immediately after the coating.
As is evident from Table 3, the sulfur sensitization and the selenium sensitization scarcely changed the sensitivity with time in the case where the compound (I) of the invention was not added, but reduced the spectral sensitivity with time in the case where the compound (I-13) or (I-31) of the invention was added.
By contrast, the tellurium sensitization used in the invention achieved the advantage that the sensitivity changed with time, but less than in the case of the sulfur sensitization or the selenium sensitization.

EXAMPLE 4

A silver bromoiodide emulsion was prepared which was the same as Example 1. This emulsion was divided into three parts. Sodium thiosulfate (1.2 × 10^-5 mol/mol Ag), chloroauric acid (1.2 × 10^-5 mol/mol Ag), and potassium thiocyanate (3 × 10^-3 mol/mol Ag) were added to a first part of the emulsion, thereby preparing an emulsion EmD (S/Au). N,N-dimethylselenourea (0.8 × 10^-5 mol/mol Ag), chloroauric acid (1.8 × 10^-5 mol/mol Ag), and potassium thiocyanate (3 × 10^-3 mol/mol Ag) were added to a second part of the emulsion, thereby preparing an emulsion EmE (Se/Au). Compound II-10 (5 × 10^-5 mol/mol Ag), chloroauric acid (1.8 × 10^-5 mol/mol Ag), and potassium thiocyanate (3 × 10^-3 mol/mol Ag) were added to a first part of the emulsion, thereby preparing an emulsion EmF (Te/Au).
Each of the three emulsions, thus prepared, was divided into parts, to which the compound (I) of the invention was added. The same process as performed in Example 1 was carried, whereby the results shown in Table 4 were obtained.
As is evident from Table 4, in any sample using a gold sensitizer, the degree of tellurium sensitization was similar to that of selenium sensitization in the case where the dye of the invention was not used, but the spectral sensitivity was much higher than had been expected in the case where the dye was used. This is perhaps because the intrinsic desensitization by dye is small is in Example 1.
The same results were obtained when the tellurium sensitizer was replaced by the compound (III-1).

EXAMPLE 5

30 ml of a 25% ammonia aqueous solution was added to 1.2 liters of a 3.0% gelatin solution containing 0.06 mol potassium bromide in a reaction vessel maintained at 65°C, while the gelatin solution were being stirred. Then, 50 cc of 0.3 mol silver nitrate solution and 50 cc of a halogen salt aqueous solution containing 0.063 mol of potassium iodide and 0.19 mol of potassium bromide were added, over 3 minutes by the double-jet method. Silver bromoiodide grains having a circle equivalent diameter of 0.15 µm and a silver iodide content of 25 mol% were thereby obtained, thus forming nuclei. Next, 60 ml of an ammonia aqueous solution was added at 65°. Further, 800 ml of a 1.5 mol silver nitrate and 800 ml of a halogen salt solution containing 0.375 mol potassium iodide and 1.13 mol potassium bromide were added simultaneously, over 80 minutes by means of the double-jet method, thereby forming the first coating layer. The emulsion, thus obtained, contained octahedral silver bromoiodide grains having an average equivalent-circle diameter of 0.71 µm. (The iodide content was 25 mol%.)
Next, acetic acid was added, neutralizing the emulsion. Further, a 1.5 mol silver nitrate solution, a 1.5 mol potassium bromide solution, and a 2 wt% gelatin solution were added into a mixer. thereby forming a silver bromide shell (i.e., the second coating layer). Grains were thereby obtained, in which the ratio of the first layer to the second layer was 1:1, and which were monodisperse octahedral core/shell emulsion grains having a circle equivalent diameter of 0.89 µm (variation coefficient: about 18%).
The emulsion was cooled to 35°C after the addition, desalted by ordinary flocculation, and washed with water. Gelatin and water were added, and the pH and pAg values were adjusted to 5.8 and 8.6, respectively, at 40°C.
This emulsion was divided into three parts. Sodium thiocyanate (3 × 10^-3 mol/mol Ag), chloroauric acid (8 × 10^-6 mol/mol Ag), and 1.6 × 10^-5 mol/mol Ag of sodium thiosulfate (EmG), 1.2 × 10^-5 mol/mol Ag of N,N-dimethylselenourea (EmH), or 3.2 × 10^-5 mol/mol Ag of compound II-10 of the invention (EmI) were added, and chemically ripened at 56°C for 60 minutes.

Each of these emulsions EmG, EmH, and EmI was divided into parts. To each of these parts, the compound (I) of the invention was first added first, and the additives specified below were added in standard amounts.

Magenta coupler	3-{3-[2-(2,4-di-tert-amylphenoxy) butylamino]benzoylamino}-1-(2,4,6-trichlorophenyl) pyrazoline-5-one
Oil	Tricresyl phosphate
Stabilizer	4-hydroxy 6 methyl-1,3,3a,7 tetraaziidene
Antifoggant	1-(m-sulfophenyl)-5-mercaptotetrazole monosodium salt
Coating aid	Sodium dodecylbenzenesulfonate
Hardener	1,2-bus(vinylsulfonacetylamino ethane
Antiseptic	Phenoxyethanol

Each resultant emulsion was coated on an undercoated triacetylcelluose film support, simultaneously with a protective layer by means of simultaneous extrusion method. As a result, Samples 50 to 64 were obtained.
Samples 50 to 52 were exposed to light for 1/100 second under an optical wedge, said light applied through a 419 nm interfering filter. Samples 53 to 65 were exposed to light for 1/100 second under an optical wedge, said light applied through a yellow filter (i.e., a SC-50 filter). Samples 50 to 64 were developed under the conditions which will be specified below. The photographic sensitivity of each sample is represented in the relative value of a reciprocal of the exposure amount required to impart an optical density of fog +0.5. The intrinsic sensitivity of each sample is indicated, such that the value of Sample 50 was defined as 100. The spectral sensitivities of Sample 53 to 58 are evaluated, such that the value of Sample 53 was defined as 100, and the spectral sensitivities of Samples 59 to 64 are measured. such that the value of Sample 59 was defined as 100.
The development process was carried out at 38° under the following conditions:

1. Color developing 2 min. 15 sec.

2. Bleaching: 6 min. 30 sec.

3. Water-washing 3 min. 15 sec.

4. Fixing 6 min. 30 sec.

5. Water-washing 3 min. 15 sec.

6. Stabilizing 3 min. 15 sec.

The processing solutions used in the processing steps specified above had the following compositions:

Color developing solution
Sodium nitrilotetraacetate	1.0g
Sodium sulfite	4.0g
Sodium carbonate	30.0g
Potassium bromide	1.4g
Hydroxyamine sulfate	2.4g
4-(N-ethyl-N-β-hydroxyethylamino)-2-methylaniline sulfate	4.5g
Water to make	1 liter

Bleaching Solution
Ammonium bromide	160.0g
Ammonia water (28%)	25.0 ml
ethylenediamine tetraacetic acid iron (II) sodium Salt	130g
Glacial acetic acid	14 ml
Water to make	1 litter

Fixing Solution
Sodium tetrapolyphosphate	2.0g
Sodium sulfite	4.0g
Ammonium thiosulfate (70%)	175.0 ml
Sodium bisulfate	4.6g
Water to make	1 litter

Stabilizing Solution
Formalin	8.0 ml
water to make	1 litter

As is evident from Table 5, in any sample not containing the dye of the invention. the degree of tellurium sensitization was similar to that of selenium sensitization in the case where the dye of the invention was not used. Nonetheless, in any sample containing the dye of the invention, the spectral sensitivity was very high.
As can be understood from Table 5, too, compounds I-33 and I-34, both represented by the formula (I) in which R₆ is a hydro9en atom (h = 0), imparted a sensitivity lower than that achieved by compounds I-3 and I-11, both represented by the formula (I) in which R₆ is are not so preferable, though they achieved, to some extent, the advantage of the present invention (that is, the intrinsic sensitivity is slightly lower than that achieved by selenium, but the spectral sensitivity higher than that achieved by selenium).

EXAMPLE 6

Emulsion were prepared in the same way as in Example 5, except that the silver nitrate solution and the halogen salt solution were not added simultaneously when the first coating layer is formed, but the additions of these solutions were started with an adjusted time lag, to form an emulsion having an average circle equivalent diameter of 0.89 µm and a variation coefficient of 24% and an emulsion having an average circle equivalent diameter of 0.91 µm and a variation coefficient of 35%.
Each of these emulsions was divided into two parts. These two parts were subjected to tellurium-gold sensitization, and selenium-gold sensitization, respectively, in the same way as in Example 5. Thereafter, 6 × 10^-4 mol/mol Ag of the compound (I-3) was added to each part of the emulsion. Using the emulsions, samples were made and tested as in Example 5. The results were as is shown in Table 6.
Further, after the coating the samples were stored for 4 days at 50°C and relative humidity of 80%. They were then color-processed, and their spectral sensitivities were evaluated, such that the value of Sample 70 was defined as 100.
As is evident from Table 6, the advantage of the invention is seen also in the polydisperse emulsion, i.e., an emulsion having a great variation coefficient, and the tellurium sensitization imparts a higher spectral sensitivity than the selenium sensitization.
However, as is seen in Table 6, a polydisperse emulsion, i.e., an emulsion having a great variation coefficient, causes a marked increase in fog during the storage at a high temperature and a high humidity, though it achieves a higher spectral sensitivity. It can be understood that a monodisperse emulsion, i.e., an emulsion having a small variation coefficient, should better be used to attain the advantage of the present invention.

EXAMPLE 7

A monodisperse silver bromide tabular emulsion was prepared by the method of Example 6 disclosed in JP-A-2-838. This emulsion had an average grain diameter of 1.05µ, a grain thickness of 0.19µ, an aspect ratio of 5.8, and a variation coefficient of 10.5% in terms of grain diameter.
The pH and pAg values of this emulsion were adjusted to 6.2 and 8.3, respectively. Then, the emulsion was divided into two parts. The first part was selenium sensitized with 1.6 × 10^-5 mol/mol Ag of N,N-dimethylselenourea at 55°C for 40 minutes by means of ripening. The second part was tellurium-sensitized with 9.6 × 10^-5 mol/mol Ag of the compound (II-15) at 55°C for 40 minutes by means of ripening.
Thereafter, each of the two resultant emulsions was divided into parts. The dye (I-3) of the present invention was added in an amount of 8 × 10^-4 mol/mol Ag. Using the emulsions, thus obtained, samples were made and tested in the same way as in Example 5 (except that the time of color developing was 1 minute 30 seconds). The results were as is shown in Table 7, in which the intrinsic sensitivity and spectral sensitivity of each sample are represented, such that the value of Sample 80 and the value of Sample 82 were defined as 100, respectively.
As is evident from Table 7, in tabular grains, too, the tellurium sensitization was slightly inferior to the selenium sensitization in the case where the dye was not used, but the spectral sensitivity, was remarkably high in the case where the dye useful in the present invention was used.

EXAMPLE 8

A monodisperse, octahedral silver bromoioide emulsion was prepared in the same was as in Example 1. The emulsion was divided into parts, which were heated to 60°. The sulfur sensitizers, the selenium sensitizers, and tellurium sensitizers, all specified in Table 8, were added to these parts of the emulsion. These parts of the emulsion were ripened for 60 minutes.
Thereafter, each of the emulsions was divided into two parts. No cyanine dye was added to the first part, whereas 3.2 × 10^-4 mol/mol Ag of the cyanine dye (I-ll) was added to the second part. Using the resultant emulsions, coated samples were made in the same way as in Example 1.
The samples, thus made, were exposed to the light applied through a 419 nm interfering filter and an optical wedge. Then, the samples were processed in the same way as in Example 1. The samples had the intrinsic sensitivities shown in Table 8, in which the intrinsic sensitivities of the all emulsions added cyanine dye were represent by relative values, such that the value of any sample not added cyanine as was defined 100.
As is evident from Table 8, in the sulfur sensitization or the selenium sensitization, the intrinsic sensitivity decreased due to the dye, regardless of the sensitizer actually used, than in the samples which had been tellurium-sensitized. Any tellurium-sensitized samples had a low intrinsic desensitization, which was a preferable result as was achieved in Example 1. Even if sulfur sensitization or selenium sensitization was performed along with tellurium sensitization, the desirable feature of tellurium sensitization was preserved; that is, the decrease in intrinsic sensitivity, caused by the dye, remained small.

Claims

A silver halide photographic light-sensitive material comprising at least one silver halide emulsion layer on a support, wherein said silver halide emulsion layer contains at least one cyanine dye of formula (I) and a silver halide emulsion subjected to a tellurium sensitization; wherein the tellurium sensitizer used in the tellurium sensitization is a compound which generates silver telluride under any one of the conditions selected from a temperature of 40°C to 95°C, a pH of 3 to 10, and a pAg of 6 to 11 in a silver halide emulsion, and the tellurium sensitization is performed in the presence of at least one tellurium sensitizer which has a pseudo-first order reaction rate constant k for producing silver telluride of 1 x 10^-8 to 1 min^-1;
wherein, Z₁ and Z₂ are the same or different, and represent an atom or group required for forming a heterocyclic ring selected from a thiazoline ring, a thiazole ring, a benzothiazole ring, a naphthothiazole ring, a dihydronaphthothiazole ring, a selenazoline ring, a selenazole ring, a benzoselenazole ring, a naphthoselenazole ring, a dihydronaphthoselenazole ring, an oxazole ring, a benzoxazole ring, a naphthoxazole ring, a pyridine ring, a quinoline ring, a tellurazole ring, a benzotellurazole ring, and a 3,3-dialkylindolenine ring;

R₁ and R₂ are the same or different, being an alkyl group or an alkenyl group, each having 10 or less carbon atoms;

R₃ and R₇ are hydrogen atoms; R₃ and R₁ may combine, and R₇ and R₂ may combine, to form a 5- or 6-membered ring;

R₄, R₅, and R₆ are the same or different, being a hydrogen atom, a C₁-C₈ alkyl group, an aryl group or a ketomethylene residual group;

R₄ and R₆ may combine to form a 5- or 6-membered ring, and if h is 2, R₄ and a different R₄ may combine, and R₅ and a different R₅ may combine, to form a 5- or 6-membered ring;

X is a pairing ion required for neutralizing the electric charge; and j and k are 0 or 1, h is 0, 1 or 2, and m is 0 or 1.
A silver halide light-sensitive material according to Claim 1, wherein Z₁ and Z₂ are an atom or group forming a heterocyclic group selected from benzoxazole, naphthoxazole, benzothiazole, naphthothiazole, dihydronaphthothiazole, benzoselenazole, naphthoselenazole, and dihydronaphthoselenazole.
A silver halide light-sensitive material according to Claim 2, wherein R₅ or R₆ is an alkyl group having 4 or less carbon atoms, or R₄ and R₆, R₄ and a different R₄, or R₅ and a different R₅ combine together to form a 5- or 6-membered ring.
A silver halide light-sensitive material according to Claim 3, wherein at least one of R₁ and R₂ is an alkyl group or an alkenyl group containing a sulfo group, a carboxyl group or a hydroxy group.
A silver halide light-sensitive material according to Claim 1, wherein the compound used in the tellurium sensitization is represented by the following formula (II):
wherein, R₁₁, R₁₂ and R₁₃ are an aliphatic group, an aromatic group, a heterocyclic group, OR₁₄, NR₁₅(R₁₆), SR₁₇, OSiR₁₈(R₁₉) (R₂₀), a halogen atom or a hydrogen atom; R₁₄ and R₁₇ are an aliphatic group, an aromatic group, a heterocyclic group, a hydrogen atom or a cation; R₁₅ and R₁₆ are an aliphatic group, an aromatic group, a heterocyclic group or a hydrogen atom; and R₁₈, R₁₉ and R₂₀ are an aliphatic group.
A silver halide light-sensitive material according to Claim 1, wherein the compound used in tellurium sensitization is represented by the following formula (III):
wherein,

R₂₁ is an aliphatic group, an aromatic group, a heterocyclic group or -NR₂₃(R₂₄), R₂₂ is -NR₂₅(R₂₆), -N(R₂₇)N(R₂₈)R₂₉ or -OR₃₀;

R₂₃, R₂₄, R₂₅, R₂₆, R₂₇, R₂₈, R₂₉ and R₃₀ are a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group or an acyl group; and R₂₁ and R₂₅, R₂₁ and R₂₇, R₂₁ and R₂₈, R₂₁ and R₃₀, R₂₃ and R₂₅, R₂₃ and R₂₇, R₂₃ and R₂₈, and R₂₃ and R₃₀ may combine, forming a ring.
A silver halide light-sensitive material according to Claim 1, wherein said silver halide emulsion is a monodisperse emulsion.
A silver halide light-sensitive material according to Claim 7, wherein the variation coefficient of said monodisperse emulsion is 30% or less.
A silver halide light-sensitive material according to Claim 8, wherein the variation coefficient of said monodisperse emulsion is 20% or less.
A silver halide light-sensitive material according to Claim 1, wherein, in the formula (I),

h is 0;

Z₁ and Z₂ are an atom or group which forms a heterocyclic nucleus selected from benzoxazole, naphthoxazole, benzothiazole and naphthothiazole;

R₃ and R₇ are hydrogen atoms;

R₆ is an ethyl group or a methyl group; and

at least one of R₁ and R₂ is an alkyl group containing a sulfo group, a carboxyl group or a hydroxy group.
A silver halide light-sensitive material according to Claim 10, wherein R₆ is an ethyl group.
A silver halide light-sensitive material according to Claim 1, wherein, in the formula (I),

h is 1;

Z₁ and Z₂ are an atom or group forming a heterocyclic nucleus selected from benzoxazole, naphthoxazole, benzothiazole, naphthothiazole, benzoselenazole and naphthoselenazole;

R₃, R₅ and R₇ are hydrogen atoms if R₄ and R₆ combine, forming a 5- or 6-membered ring; and

R₅ is a C₁-C₈ alkyl group, and R₃, R₄ and R₇ represent hydrogen atoms if R₄ and R₆ do not combine to form a ring.
A silver halide light-sensitive material according to Claim 1, wherein, in the formula (I);

h is 2;

Z₁ and Z₂ are an atom or group forming a heterocyclic nucleus selected from benzoxazole, naphthoxazole, benzothiazole, naphthothiazole, benzoselenazole and naphthoselenazole; and

R₄ and a different R₄, R₅ and a different R₅, or R₄ and R₆ combine to form a 5- or 6-membered ring.
A silver halide light-sensitive material according to Claim 1, which has been sensitized with an additional gold sensitizer.
A silver halide light-sensitive material according to Claim 1, which has been sensitized with an additional thiocyanate salt.
A silver halide light-sensitive material according to Claim 1, which has been sensitized with an additional sulfur sensitizer.
A silver halide light-sensitive material according to Claim 1, which has been sensitized with an additional selenium sensitizer.
A silver halide light-sensitive material according to Claim 1, wherein the tellurium sensitization is performed in the presence of at least one tellurium sensitizer which has a pseudo-first order reaction rate constant k for producing silver telluride of 1 x 10^-7 to 1 x 10^-1 min^-1.
A tellurium-sensitized silver halide emulsion, wherein the tellurium sensitizer used in the tellurium sensitization is a compound which generates silver telluride under any one of the conditions selected from a temperature of 40°C to 95°C, a pH of 3 to 10, and a pAg of 6 to 11 in a silver halide emulsion, and the tellurium sensitization is performed in the presence of at least one tellurium sensitizer which has a pseudo-first order reaction rate constant k for producing silver telluride of 1 x 10^-8 to 1 min^-1, which emulsion contains at least one cyanine dye represented by the following formula (I):
wherein,

Z₁ and Z₂ are the same or different, and are an atom or group required for forming a heterocyclic ring selected from a thiazoline ring, a thiazole ring, a benzothiazole ring, a naphthothiazole ring, a dihydronaphthothiazole ring, a selenazoline ring, a selenazole ring, a benzoselenazole ring, a naphthoselenazole ring, a dihydronaphthoselenazole ring, an oxazole ring, a benzoxazole ring, a naphthoxazole ring, a pyridine ring, a quinoline ring, a tellurazole ring, a benzotellurazole ring, and a 3,3-dialkylindolenine ring;

R₁ and R₂ are the same or different, and represent an alkyl group or an alkenyl group, each having 10 or less carbon atoms;

R₃ and R₇ are hydrogen atoms; R₃ and R₁ may combine, and R₁ and R₂ may combine, to form a 5- or 6-membered ring;

R₄, R₅, and R₆ are the same or different, and are a hydrogen atom, a C₁-C₈ alkyl group, an aryl group or a ketomethylene residual group;

R₄ and R₆ may combine to form a 5- or 6-membered ring, and if h is 2, R₄ and a different R₄ may combine, and R₅ and a different R₅ may combine, to form a 5- or 6-membered ring;

X is a pairing ion required for neutralizing the electric charge; and

j and k are 0 or 1, h is 0, 1 or 2, and m is 0 or 1.
Use of tellurium sensitization for decreasing the intrinsic desensitization of a silver halide emulsion caused by the presence of at least one cyanine dye of formula (I):
wherein, Z₁ and Z₂ are the same or different, and represent an atom or group required for forming a heterocyclic ring selected from a thiazoline ring, a thiazole ring, a benzothiazole ring, a naphthothiazole ring, a dihydronaphthothiazole ring, a selenazoline ring, a selenazole ring, a benzoselenazole ring, a naphthoselenazole ring, a dihydronaphthoselenazole ring, an oxazole ring, a benzoxazole ring, a naphthoxazole ring, a pyridine ring, a quinoline ring, a tellurazole ring, a benzotellurazole ring, and a 3,3-dialkylindolenine ring;

R₁ and R₂ are the same or different, and are an alkyl group or an alkenyl group, each having 10 or less carbon atoms;

R₃ and R₇ are a hydrogen atom; R₃ and R₁ may combine, and R₇ and R₂ may combine, to form a 5- or 6-membered ring;

R₄, R₅, and R₆ are the same or different, and are a hydrogen atom; a C₁-C₈ alkyl group, an aryl group or a ketomethylene residual group;

R₄ and R₆ may combine together to form a 5- or 6-membered ring, and if h is 2, R₄ and a different R₄ may combine, and R₅ and a different R₅ may combine, to form a 5- or 6-membered ring;

X is a pairing ion required for neutralizing the electric charge; and

j and k are 0 or 1, h is 0, 1 or 2, and m is 0 or 1.