Light-sensitive silver halide color photographic material

Abstract

 There is disclosed a light-sensitive silver halide color photographic material, comprising on a substrate material at least silver halide emulsion layers which are respectively blue-sensitive, green-sensitive and red-sensitive, wherein the material has a DIR compound, contains a formalin scavenger, and also at least the green-sensitive emulsion layer is constituted of a single layer and contains a 5-pyrazolone type magenta coupler.

Description

BACKGROUND OF THE INVENTION

[0001] This invention relates to a negative-type light-sensitive color photographic material suitable for full color photographing.

[0002] Presently, color photography widely spread is the so-called negative-positive system in which photographing is practiced with a color negative film and color print is effected by enlarging onto a color paper.

[0003] One of the reasons is that a color negative film has very broad exposure latitude, with very little probability of failure during photographing, and even users in general having no special knowledge can take color photographs without any particular concern.

[0004] "Having broad exposure latitude" refers to the fact that the gradation is good over wide exposure dose range from the shadow portion with little exposure dose to the highlight portion with much exposure dose in the so-called characteristic curve in which the exposure dose is taken on the axis of abscissa and the color formed density on the axis of or ordinate.

[0005] If the gradation is inferior, color reproducibility and tone reproducibility of a dye image will be deteriorated.

[0006] Color negative film, as diferent from color reversal film or color paper, is a light-sensitive material for which gradation is demanded to be strictly controlled over wider range of exposure dose. For that reason, color negative films for photography commercially available at the present time are made to have an overlaid constitution comprising a plurality of emulsion layers of higher sensitivity layer containing greater grain sizes of silver halide grains and lower sensitivity layer containing smaller grain sizes of silver halide grains for the respective color sensitive layers to the lights of blue color, green color and red color. Further, the so-called DIR compound for forming consequently a developing inhibitor through the reaction with the oxidized product of the developing agent is employed.

[0007] Such technique is inherent in color negative film, and particularly the DIR compound improves not only gradation but also sharpness, graininess and color reproducibility of a dye image, and is essential in color negative film.

[0008] Since color negative film comprises an overlaid layer constitution having a plurality of emulsion layers containing silver halide grains with different grain sizes as described above, and further controls strictly gradation by use of a DIR compound, it has such drawbacks as deterioration of color reproducibility and tone reproducibility due to deterioration of gradation for such reasons that storage stability of light-sensitive material is inferior under formalin gas atmosphere, and that stability to fluctuations in processing conditions is inferior. Whereas, since a color negative film is subjected to developing processing in various laboratories as compared with a color reversal film, developing processing will be performed under processing conditions with greater fluctuation width. Accordingly, a color negative film has been demanded to have high stability particularly to fluctuations in processing conditions.

[0009] As the technique for improving the so-called gradation stability which strictly controls such gradation, there has been known the method in which the silver halide emulsions with equal mean grain size are chemically sensitized, then sensitizing dyes are added to the respective emulsions with various molar ratios, and the emulsions are again mixed as disclosed in Japanese Provisional Patent Publication No. 244944/1985. However, according to this method, adsorption equilibrium of the dyes will undesirably occur between grains during the standing period before coating.

SUMMARY OF THE INVENTION

[0010] An object of the present invention is to provide a light-sensitive silver halide color photographic material, having excellent gradation stability even when placed under formalin gas atmosphere, and also to fluctuations under developing processing conditions.

[0011] The object of the present invention has been accomplished by a light-sensitive silver halide color photographic material, comprising on a substrate material at least silver halide emulsion layers which are respectively blue-sensitive, green-sensitive and red-sensitive, wherein said material has a DIR compound, contains a formalin scavenger, and also at least said green-sensitive emulsion layer is constituted of a single layer and contains a 5-pyrazolone type magenta coupler.

BRIEF DESCRIPTION OF THE DRAWING

[0012] 

Fig. 1 is a graph showing the characteristic. curve which is the standard (broken line) and the characteristic curve which is to be evaluated (solid line) of the light-sensitive photographic material.

Fig. 2 is a graph showing the point gamma of the light-sensitive photographic material of the characteristic curve which is the standard (broken line) and the characteristic curve which is to be evaluated (solid line).

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The DIR compound to be used in the light-sensitive material of the present invention is a compound which eliminates a developing inhibitor or a compound capable of releasing a developing inhibitor through the reaction with an oxidized product of a color developing agent.

[0014] The above-mentioned compound capable of releasing a developing inhibitor may be one which releases the developing inhibitor either imagewise or non-imagewise.

[0015] Those which release developing inhibitors imagewise may include, for example, those through the reaction with the oxidized product of color developing agents. Examples of those which release developing inhibitors non-imagewise may include those which utilize the TIME groups as described below.

[0016] The DIR compounds to be used in the present invention are represented by the following formulae. A - (Y)m (D-1) wherein A represents a coupler residue, m represents 1 or 2, Y represents a group bonded to the coupling position of the coupler residue A and eliminatable through the reaction with the oxidized product of the color developing agent, which is a developing inhibitor group or a group capable of releasing a developing inhibitor.

[0017] In the formula (D-1), Y may be typically represented by the formulae (D-2) to (D-20) set forth below.

[0018] In the formulae (D-2) to (D-7), Rd₁ represents a hydrogen atom, a halogen atom or an alkyl, alkoxy, acylamino, alkoxycarbonyl, thiazolidinylideneamino, aryloxycarbonyl, acyloxy, carbamoyl, N-alkylcarbamoyl, N,N-dialkylcarbamoyl, nitro, amino, N-arylcarbamoyloxy, sulfamoyl, N-alkylcarbamoyloxy, hydroxy, alkoxycarbonylamino, alkylthio, arylthio, aryl, heterocyclic, cyano, alkylsulfonyl or aryloxycarbonylamino group. n represents 0, 1 or 2, and when n is 2, the respective Rd₁'s may be either the same or different. The total carbon atoms contained in n Rdi's may be 0 to 10. On the other hand, the carbon atoms contained in Rd₁ in the formula (D-6) may be 0 to 15.

[0019] In the above formula (D-6), X represents an oxygen atom or a sulfur atom.

[0020] In the formula (D-8), Rd₂ represents an alkyl group, an aryl group or a heterocyclic group.

[0021] In the formula (D-9), Rd₃ represents a hydrogen atom, an alkyl, cycloalkyl, aryl or heterocyclic group, Rd₄ represents a hydrogen atom, a halogen atom or an alkyl, cycloalkyl, aryl, acylamino, alkoxycarbonylamino, aryloxycarbonylamino, alkanesulfonamide, cyano, heterocyclic, alkylthio or amino group.

[0022] When Rdi, Rd₂, Rd₃ or Rd₄ represents an alkyl group, the alkyl group includes those having substituents, and may be either straight or branched.

[0023] When Rd₁, Rd₂, Rd₃ or Rd₄ represents an aryl group, the aryl group includes those having substituents.

[0024] When Rd,, Rd₂, Rd₃ or Rd₄. represents a heterocyclic group, the heterocyclic group includes those having substituents, preferably 5- or 6-membered monocyclic or fused rings containing at least one selected from nitrogen atom, oxygen atom and sulfur atom as the hetero atom, and may be selected from the groups of, for example, pyridyl, quinolyl, furyl, benzothiazolyl, oxazolyl, imidazolyl, thiazolyl, triazolyl, benzotriazolyl, imide or oxazine group.

[0025] The carbon atoms contained in Rd₂ in the formula (D-8) may be 0 to 15.

[0026] In the above formula (D-9), the total carbon atoms contained in Rd₃ and Rd₄ may be 0 to 15.

wherein the TIME group is a group bound to the coupling position of A which cleavable through the reaction with the oxidized product of the color developing agent, which is a group cleaved successively after cleavage from the coupler, until finally can release the INHIBIT groups with adequate control; n is 1 to 3, and when it is 2 or 3, the respective TIME groups may be either the same or different. The INHIBIT group is a group which becomes a developing inhibitor by the above-mentioned release (e.g. the group represented by the above formulae (D-2) to (D-9)).

[0027] In the formula (D-10), the -TIME group may be typically represented by the formulae (D-11) to (D-19) set forth below.

[0028] In the formulae (D-11) to (D-15) and (D-18), Rd₅ reprsents a hydrogen atom, a halogen atom or an alkyl, cycloalkyl, alkenyl, aralkyl, alkoxy, alkoxycarbonyl, anilino, acylamino, ureido, cyano, nitro, sulfonamide, sulfamoyl, carbamoyl, aryl, carboxy, sulfo, hydroxy or alkanesulfonyl group. In the formulae (D-11) to (D-13), (D-15) and (D-18), Rds's may be mutually bonded together to form a fused ring. In the formulae (D-11), (D-14), (D-15) and (D-19), Rd_s represents an aralkyl, alkenyl, alkyl, cycloalkyl, heterocyclic or aryl group. In the formulae (D-16) and (D-17), Rd₇ represents a hydrogen atom or an alkyl, alkenyl, aralkyl, cycloalkyl, heterocyclic or aryl group. Each of Rd₈ and Rd_s in the formulae (D-19) represents a hydrogen atom or an alkyl group (preferably an alkyl group having 1 to 4 carbon atoms), k in the formulae (D-11). (D-15) to (D-18) represents an integer of 0, 1 or 2, K in the formulae (D-11) to (D-13), (D-15) and (D-18) represents an integer of 1 to 4, m in the formula (D-16) represents an integer of 1 or 2. When t and m are 2 or more, the respective Rd₅ and Rd₇ may be either the same or different. n in the formula (D-19) represents an integer of 2 to 4, and Rd₈ and Rd_s in number of n may be each the same or different. B in the formulae (D-16) to (D-18) represents an oxygen atom or

[0029] (Rd₆ represents the same meaning as already defined), and - in the formula (D-16) may be either a single bond or a double bond, and m is 2 in the case of the single bond or m is 1 in the case of the double bond.

wherein T, represents a component which cleaves SR(T2 NHIBIT, SR represents a component which forms (T₂)_m INHIBIT through the reaction with the oxidized product of the developing agent after formation of SR(̵T₂)̵ INHIBIT, T₂ represents a component which cleaves INHIBIT after formation of (T₂)̵_m INHIBIT, INHIBIT represents a developing inhibitor and t and m each 0 or 1.

[0030] The component represented by SR may be one which can form the component as mentioned above through the reaction with the oxidized product of the developing agent, and may include, for example, a coupling component which undergoes the coupling reaction with the oxidized product of the developing agent or a redox component which undergoes the redox reaction with the oxidized product of the developing agent.

[0031] As the coupler component, there may be included yellow couplers, magenta couplers and cyan couplers such as acylacetanilides, 5-pyrazolones, pyrazoloazoles, phenols, naphthols, acetophenones, indanones, carbamoylacetanilides, 2(5H)-imidazolones, 5-isoxazolones, uracils, homophthalimides, ox- azolones, 2,5-thiadiazoline-1,1-dioxides, triazolothiadiazines and indoles, and otherwise those which form various dyes or form no dye. The (T_i )̵SR(̵T₂)̵_m INHIBIT should be preferably bonded to the active site of the component A of the formula (D-1).

[0032] When SR is a coupler component, SR is bonded to (̵T₁)̵ and (̵T₂)̵_m INHIBIT so as to function for the first time as the coupler after cleavage from (̵T₁)̵.

[0033] For example, the oxygen atom of hydroxyl group when the coupler component is phenols or naphthols, the oxygen atom at the 5-position or the nitrogen atom at the 2-position of the enantiomer when it is 5-pyrazolones, and also the oxygen atom of hydroxyl group of the enantiomer when it is acetophenones or indanones, are preferably bonded to (̵T₁)̵, and (̵T₂)̵ INHIBIT to the active site of the coupler.

[0034] In the case when SR is a redox component, its examples may include hydroquinones, catechols, pyrogallols, aminophenols (e.g. p-aminophenols and o-aminophenols), naphthalenediols (e.g. 1,2-naphthalenediols, 1,4-naphthalenediols and 2,6-naphthalenediols) and aminonaphthols (e.g. 1,2-aminonaphthols, 1,4-aminonaphthols and 2,6-aminonaphthols),

[0035] In the case when SR is a redox component, SR is bonded to (̵T₁ )̵and (̵T₂)̵_m INHIBIT so as to function for the first time as the redox component after cleavage from (̵T₁)̵.

[0036] Examples of the group represented by T, and T₂ may include those represented by the formulae (D-11) to (D-19) as described above.

[0037] As the developing inhibitor represented by INHIBIT, for example, those represented by the formulae (D-2) to (D-9) as described above may be included.

[0038] Among the DIR compounds, preferred are those wherein Y is represented by the formula (D-2), (D-3), (D-8), (D-10) or (D-20), and among (D-10) and (D-20), those wherein INHIBIT is represented by the formula (D-2), (D-3), (D-6) (particularly when X of the formula (D-6) is an oxygen atom), or (D-8) are preferred.

[0039] As the coupler component represented by A in the formula (D-1), yellow color image forming coupler residues, magenta color image forming coupler residues, cyan color image forming coupler residues and no color exhibiting coupler residues may be included.

[0040] As preferred DIR compounds to be used in the present invention, the compounds as shown below may be included, but these are not limitative of the invention.

[0041] Exemplary compounds:

[0042] Groups of R₁, R₂ and Y

[0043] 

[0044] Specific examples of the DIR compounds which can be used in the present invention, including these are described in U.S. Patents No. 4,234,678, No. 3,227,554, No. 3,617,291, No. 3,958,993, No. 4,149,886 and No. 3,933,500; Japanese Provisional Patent Publications No. 56837/1982 and No. 13239/1976; U.S. Patents No. 2,072,363 and No. 2,070,266; and Research Disclosure No. 21228, December, 1981.

[0045] The DIR compound is preferably used in an amount of 0.0001 to 0.1 mole, particularly 0.001 to 0.05 mole, per mole of silver halide.

[0046] The place in which the DIR compound to be used in the present invention is added may be any place which can affect developing of the silver halide in the emulsion layer which is single layer constitution as described below, preferably a silver halide emulsion layer, more preferably an emulsion layer which is single layer constitution.

[0047] The formalin scavanger to be used in the present invention is a compound which reacts with formaldehyde gas, particlarly preferably one represented by the following formula [S].

Here, R₁ and R₂ represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an acyl group. a carbamoyl group, an iminomethyl group or an amino group, said respective groups including those having substituents, being also inclusive of those wherein R, and R₂ form rings, and when R₁ and R₂ form no ring, at least one of these R₁ and R₂ is an acyl group, a carbamoyl group or an amino group.

[0048] A represents -

[0049] Of the formalin scavengers represented by the formula (S), preferred are the compounds represented by the formula (S-I), (S-II), (S-III) or (S-IV).







Here, R₃ represents a divalent alkyl group, R₄, R₅ and R₇ represent a hydrogen atom, an alkenyl gorup, an alkyl group or

[0050] (R is an alkyl group), R6 represents a hydrogen atom, an alkyl group or an amino group, and Rs represents an alkyl group, the respective groups including those having substituents. Also, here R₄ and Rs, and R₇ and R₉ include those which form rings. As said substituents, amino groups, hydrocarbon residues or -OR groups (R is a hydrocarbon residue) may be included. R_s represents a carbonyl group or -C(= NH)-group, R₁₀ represents a hydrogen atom, an alkyl group, a cyclohexyl group, a phenyl group, an aralkyl group, an alkoxyl group, an aryloxy group, a carbamoyl group, an alkoxycarbonyl group or a cyano group, and these respective groups are inclusive of those having substituents. R₁₁ represents a hydrogen atom, an alkyl group, a cyclohexyl group, a phenyl group, an aralkyl group, a heterocyclic residue, a benzoyl group, a sulfonalkyl group, a sulfonaryl group, a carboxyalkyl group, a carbamoyl group or a thiocarbamoyl group, and the respective groups are inclusive of those having substituents.

[0051] In the following, particularly preferable ones of the formalin scavenger are shown, but the present invention is not limited thereto.

[0052] Of the formalin scavengers shown here, for example, (S-1), (S-2), (S-5), (S-6), (S-7) and (S-8) are commercially available compounds, and (S-7) to (S-16) can be synthesized according to the methods described in G.B. Patent No. 717,287, U.S. Patents No. 2,731,472 and No. 3,187,004, Japanese Provisional Patent Publication No. 79248/1983, and (S-19) can be synthesized according to the methods as described in Beilstein Handbuch der Organischer Chemie H98, (1921), Chemische der Berichte 54, B, 1802-1833 and 2441-2477, (1921), Bulletin of the Chemical Society of Japan, 39, 1559-1567 and 1734-1738 (1966). Also, (S-28) can be synthesized according to the method as described in German Patent No. 148,108.

[0053] The formalin scavenger to be used in the present invention may be used as a combination of two or more kinds.

[0054] The formalin scavenger to be used in the present invention can be used as contained in at least one layer of a protective layer, a silver halide emulsion layer, an intermediate layer, a filter layer, an antihalation layer and other layers of the light-sensitive silver halide color photographic material. Preferably, it may be added in the silver halide emulsion layer containing a magenta coupler or in the layers farther than said layer from the support, and also more preferably in the layer forming no dye through developing than the layer forming a dye.

[0055] The formalin scavenger to be used in the present invention can be added in these layers in the coating solution as such or dissolved in water or a low boiling point organic solvent which does not affect to the light-sensitive silver halide color photographic material such as alcohols. Also, the formalin scavenger of the present invention can be dissolved in a high boiling point organic solvent, and the solution emulsified in an aqueous solution can be added.

[0056] The formalin scavenger to be used in the present invention may be added in an amount appropriately of 5 x 10-⁵ mole to 1 mole, preferably 1 x 10-⁴ mole to 5 x 10-¹ mole, more preferably 5 x 10-³ mole to 1 x 10^-1 mole, per 1 m² of the light-sensitive silver halide color photographic material.

[0057] The pyrazolone type magenta coupler to be used in the present invention is represented by the following formula.

[0058] In the formula, Cp represents a pyrazolone type coupler residue, ^* represents the coupling position of the coupler, X represents a hydrogen atom or a group which is eliminated when a dye is formed through the coupling with an oxidized product of an aromatic primary amine color developing agent.

[0059] Examples of the eliminatable group represented by X may include monovalent groups such as halogen atoms, alkoxy groups, aryloxy groups, heterocyclicoxy groups, acyloxy groups, alkylthio groups, arylthio groups, heterocyclic thio groups,

(X, in the formula represents mono valent groups such as a nitrogen atom or a group of atoms necessary for formation of a 5- to 6-membered ring together with at least one atom selected from a carbon atom, an oxygen atom, a nitrogen atom and a sulfur atom), acylamino gorups and sufonamide groups, and divalent groups such as alkylene groups. In the case of a divalent group, X forms a dimer.

[0060] In the following, specific examples are enumerated. Halogen atom: chlorine, bromine, fluorine

[0061] Alkoxy group:

[0062] Aryloxy group:

[0063] Heterocyclicoxy group:

[0064] Acyloxy group:

[0065] Alkylthio group:

[0066] Arylthio group:

[0067] Heterocyclicthio group:





a pyrazolyl group, an imidazolyl group, a triazolyl group, a tetrazolyl group,

[0068] Acylamino group:

[0069] Sulfonamide group:

[0070] Alkylene group:

In the present invention, a particularly great effect can be recognized when X is a hydrogen atom.

[0071] As the pyrazolone type magenta coupler, those represented by the following formulae (M-1) and (M-2) are preferred.

[0072] In the above formulae (M-1) and (M-2), R₂ represents hydrogen atom or a substituent, R₃ represents a substituent, X has the same meaning as X in the formula (I), t represents 1 to 5, and when t is 2 or more, the respective R₂'s may be either the same or different.

[0073] Examples of the substituent represented by R₂ may include halogen atoms, the respective groups of alkyl, cycloalkyl, aryl or heterocyclic groups, bonded directly or through a divalent atom or group.

[0074] Examples of the above-mentioned divalent atom or group may include an oxygen atom, a nitrogen atom, a sulfur atom, carbonylamino, aminocarbonyl, sulfonylamino, aminosulfonyl, amino, carbonyl, car- bonyloxy, oxycarbonyl, ureylene, thioureylene, thiocarbonylamino, sulfonyl or sulfonyloxy.

[0075] The above-mentioned alkyl, cycloalkyl, aryl and heterocyclic groups as examples of the substituent represented by R₂ include those having substituents. As said substituents, there may be included, for example, halogen atoms, nitro, cyano, alkyl, alkenyl, cycloalkyl, aryl, alkoxy, aryloxy, alkoxycarbonyl, aryloxycarbonyl, carboxy, sulfo, sulfamoyl, carbamoyl, acylamino, ureido, urethane, sulfonamide, heterocyclic, arylsulfonyl, alkylsulfonyl, arylthio, alkylthio, alkylamino, anilino, hydroxy, imide and acyl groups.

[0076] Examples of R₃ may include the respective groups of alkyl, cycloalkyl, aryl and heterocyclic groups, and these groups are inclusive of those having substituents. Examples of said substituents may include those as exemplified for the substituents possessed by the respective groups mentioned as examples of R₂.

[0077] As the elminatable group of X, an alkylthio group, an arylthio group, an aryloxy group, an acyloxy group,

(X_I) has the same meaning as X as described above) and an alkylene group are particularly preferred.

[0078] Specific examples of the pyrazolone type magenta coupler to be used in the present invention are mentioned below, but the present invention is not limited thereto.

[0079] Exemplary compounds

[0080] In the present invention, the amount of the magenta coupler added may be preferably 2 x 10-⁵ to 1 x 10-³ mole/m², more preferably 5 x 10-⁵ to 1 x 10-³ mole/m².

[0081] The constitution that the color Sensitive layer is a single layer is also inclusive of the case when a plurality of emulsion layers which are the same in color sensitivity, being the same in the kind of the couplers contained in the emulsion layers, grain sizes of the silver halide grains, the halogen compositions and crystal habits, and also the ratio of the coupler to the silver halide, are arranged as continuous layers.

[0082] Here, "the same in color sensitivity" or "the same color sensitivity" may be the same in the point of, for example, blue light-sensitivity, green light-sensitivity or red light-sensitivity, and is not required to be totally the same in spectral sensitivity characteristics.

[0083] In the present invention, the green light-sensitive layer is a single layer, and further preferably, both the blue light-sensitive layer and the green light-sensitive layer are single layers. Particularly, all of the blue light-sensitive, green light-sensitive and red light-sensitive silver halide emulsion layers are preferably single layers, respectively.

[0084] When the same color sensitive layer has a single layer constitution, the number of the layers coated of the light-sensitive layer can be reduced as compared with the overlaid constitution of the prior art, whereby the film can be made thinner. Therefore, production efficiency and sharpness are improved, and graininess is also improved. The film thickness is preferably 20 to 3 u.m, particularly 15 to 5 µm, after drying.

[0085] The exposure latitude is the width of light received at which the exposure effect with a significant difference can be exhibited, particularly the exposure region from the highlight to the deep shadow in the characteristic curve, and is determined by the method defined in "Shashin no Kagaku" (Chemistry of Photography), p. 393 (published by Shashin Kogyo Shuppansha, Japan, 1982).

[0086] More specifically, it is the difference in log H's between the two points where the slope of the tangential line at the leg portion and the shoulder portion of the characteristic curve represented with log H as the axis of abscissa and the transmission density as the axis of ordinate becomes 0.2.

[0087] The light-sensitive material of the present invention is preferably one having an exposure latitude measured according to the method as described above of 3.0 or more, particularly 3.0 to 8.0.

[0088] As the means for making the exposure latitude of the silver halide emulsion layer which is a single layer 3.0 or more, it is possible to use the method in which silver halide grains with different sensitivities are used as a mixture. Specifically, there may be included, for example, the method in which silver halide grains with different grain sizes are used as a mixture, and the method in which the desensitizer is contained in at least a part of the silver halide grains.

[0089] For obtaining a broad exposure latitude, there is a method in which two kinds of monodispersed grains having different grain sizes and each sensitized are combinedly used. In this case, a mean grain size of the grains having larger grain size is preferably 0.2 to 2.0 u.m and that of the grains having smaller grain size is preferably 0.05 to further one or more of silver halide grains having an intermediate mean grain size may be also combined.

[0090] Also, the mean grain size of the silver halide grains with the maximum mean grain size should be preferably 1.5 to 40 times as that of the silver halide grains with the minimum mean grain size.

[0091] For obtaining a broad exposure latitude, silver halide grains with different mean grain sizes can be also used as a mixture, but by using silver halide grains containing a desensitizer in place of the low sensitivity silver halide grains with small grain sizes, the mean grain size difference can be made smaller without changing the sensitivity of the silver halide grains, and further it becomes possible to use silver halide grains with equal mean grain size and different sensitivities as a mixture.

[0092] Thus, by use of silver halide grains containing a desensitizer, the exposure latitude can be obtained even if the fluctuation coefficient of the grains as a whole may be made smaller.

[0093] Therefore, these silver halide grains with small fluctuation coefficient exposed to the same environment are preferably stabilized in photographic performances relative to changes with lapse of time and fluctuations in developing processing. Further, in aspect of production technique, it becomes also possible to chemically sensitize a mixed system of silver halide grains with different sensitivities in the same batch.

[0094] As the desensitizer, in addition to metal ions, various ones such as antifoggants, stabilizers and densitizing dyes can be used.

[0095] In the present invention, the metal ion doping method is preferred. As the metal ion to be used for doping, there may be included the metal ions of the groups Ib, Ilb, Ilia, lllb, IVb, Va and VIII in the periodic table of elements. Preferred metal ions may include Au, Zn, Cd, TI, Sc, Y, Bi, Fe, Ru, Os, Rh, lr, Pd, Pr, Sm and Yb. Particularly, Rh, Ru, Os and Ir are preferred. These metal ions can be used as, for example, halogeno complexes, and the pH of the AgX suspended system during doping is preferably 5 or lower.

[0096] The amount of these metal ions doped will differ variously depending on the kind of the metal ion, the grain size of the silver halide grains, the doping position of the metal ion, the desired sensitivity, etc., but may be preferably 10-¹⁷ to 10-² mole, further 10-¹² to 10-³ mole, particularly 10-⁹ to 10-⁴ mole, per mole of AgX.

[0097] Further, by selection of the kind of the metal ion, the doping position and the doping amount, various different sensitivities and qualities can be given to the silver halide grains.

[0098] With a doping amount of 10-² mole/AgX or less, great influence will be scarcely given to the growth of the grains, and hence silver halide grains with small grain size distribution can be prepared under the same grain growth conditions, even by growth in the same batch.

[0099] After the silver halide grains with different doping conditions are adjusted in conditions to be provided for practical application, these can be also made up in the same batch by mixing at a predetermined ratio and subjected to chemical sensitization. The respective silver halide gains receive the sensitizing effects based on their qualities, whereby an emulsion having a broad exposure latitude depending on the sensitivity difference and the mixing ratio can be obtained.

[0100] As the above-mentioned antifoggants or stabilizers, there may be included azoles (e.g. benzthiazolium salt, indazoles, triazoles, benztriazoles and benzimidazoles), heterocyclic mercapto compounds (e.g. mercaptotetrazoles, mercaptothiazoles, mercaptothiadiazoles, mercaptobenzthiazoles, mercaptobenzimidazoles and mercaptopyrimidines), azaindenes (e.g. tetraazaindenes and pentaazaindenes), nucleic acid decomposed products (e.g. adenine and guanine), benzenethiosulfonates and thioketo compounds.

[0101] As the desensitizing dyes, there may be included cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes and hemioxonol dyes.

[0102] As the position where the desensitizer exists, it is preferably mixed internally of the silver halide grains in the points of preservability of the light-sensitive material and standing stability of the coating solution, and its distribution may be either uniform, localized at the central portion of grain or the intermediate positions, or also gradually reduced from the central portion of grain toward outside.

[0103] From the standpoint of production efficiency, the case where the desensitizer exists as localized at the central portion of the grain is preferred, and by use of the system in which seed grains with small fluctuation coefficient are used, the steps of grain growth et seq can be proceeded in the same batch.

[0104] The light-sensitive material of the present invention desirably has at least one color sensitive layer (e.g. blue light-sensitive layer) containing AgX grains which contain a desensitizer. Preferably, it is the case when the green light-sensitive layer contains AgX grains which contain a desensitizer, more preferably when the blue light-sensitive layer and the green light-sensitive layer contain them, most preferably when all of the color light-sensitive layers contain them.

[0105] Also, the fluctuation coefficient defined by the ratio S/ r of the standard deviation of grain size (S) as the silver halide grains contained in the respective silver halide emulsion layers and the mean grain size ( r) is preferably 0.4 or less, more preferably 0.33 or less, further preferably 0.25 or less, particularly preferably 0.20 or less.

[0106] The mean grain size ( F) is defined by the following formula when the number of grains with a grain size r_; (in the case of a cubic silver halide grain, its length of one side, or in the case of a grain with other shape than cubic, the length of one side of the cube calculated to have the same volume) is n_i:

[0107] The standard deviation (S) can be defined by the following formula:

The relationship of grain size distribution can be determined according to the method described in the essay of Tribel and Smith in "Empirical Relationship between Sensitometry Distribution and Grain Size Distribution in Photography", The Photographic Journal, Vol. LXXIX (1949), pp. 330 - 338.

[0108] As the silver halide emulsion to be used in the light-sensitive material of the present invention, any of conventional silver halide emulsions can be used, but a silver halide containing substantially iodine in the halogen composition (e.g. silver iodobromide, silver iodochlorobromide) may be preferred, particularly preferably silver iodobromide with respect to sensitivity. The amount of iodine may be preferably 1 mole % to 20 mole %, particularly 3.5 mole % to 12 mole %.

[0109] A core/shell type silver halide emulsion to be used in the present invention preferably has a grain structure comprising two or more phases different in silver iodide content and comprises silver halide grains in which a phase containing a maximum silver iodide content (referred to as "core") is other than the outermost surface layer (referred to as "shell").

[0110] The content of silver iodide in an inner phase (core) having the maximum silver iodide content is preferably 6 to 40 mole %, more preferably 8 to 40 mole %, particularly preferably 10 to 40 mole %. The content of silver iodide in the outermost surface layer is preferably less than 6 mole %, more preferably 0 to 4.0 mole %.

[0111] A ratio of the shell portion in the core/shell type silver halide grains is preferably 10 to 80 %, more preferably 15 to 70 %, particularly preferably 20 to 60 % in terms of volume.

[0112] Also, a ratio of the core portion is preferably, in terms of volume, 10 to 80 %, more preferably 20 to 50 % based on the whole grains.

[0113] Difference of silver iodide content between the core portion having higher silver iodide content and the shell portion having less silver iodide content of the silver halide grains may be clear with sharp boundary or may be hazy where boundary is not clear and the content continuously changes. Also, those having an intermediate phase with silver iodide content between those of the core portion and the shell portion, between the core and the shell, may be preferably used.

[0114] In case of the core/shell type silver halide grains having the above intermediate phase, a volume of the intermediate phase is preferably 5 to 60 %, more preferably 20 to 55 % based on the whole grain. Differences of the silver iodide content between the shell and the intermediate phase, and between the intermediate phase and the core are each preferably 3 mole % or more and the difference of the silver iodide content between the shell and the core is preferably 6 mole % or more.

[0115] The core/shell type silver halide emulsion can be prepared according to the known methods as disclosed in Japanese Provisional Patent Publications No. 177535/1984, No. 138538/1985. No. 52238/1984, No. 143331/1985, No. 35726/1985 and No. 258536/1985.

[0116] For producing silver iodobromide or silver bromide, soluble silver salt and soluble halide are generally used, but as clear from the following Examples, iodide salts are preferably used in the form of silver iodide fine crystals in the point of preservability and processing stability of the light-sensitive material.

[0117] Also, silver iodobromide fine crystals having high Agl content are similarly and preferably used as the silver iodide fine crystals.

[0118] Distribution condition of the silver iodide in the above coreshell type silver halide grains can be determined by various physical measuring method and, for example, it can be examined by the measurement of luminescence at low temperature or X-ray diffraction method as described in Lecture Summary of Annual Meeting, Japanese Photographic Association, 1981.

[0119] The core/shell type silver halide grain may be any shape of normal crystal such as cubic, tetradecahedral and octahedral, or twinned crystal, or mixtures thereof, but preferably normal crystal grains.

[0120] Said emulsion can be chemically sensitized in the conventional manner, and optically sensitized to a desired wavelength region by use of a sensitizing dye.

[0121] In the silver halide emulsion, antifoggants and stabilizers can be added. As the binder for said emulsion, gelatin can be advantageously used.

[0122] The emulsion layer and other hydrophilic colloid layers can be hardened, and also a plasticizer, a dispersion (latex) of a water-insoluble or difficultly soluble synthetic polymer can be contained therein.

[0123] In the emulsion layer of a light-sensitive material for color photography, couplers are used.

[0124] Further, there can be used colored couplers having the effect of color correction, competitive couplers and compounds releasing photographically useful fragments such as developer, silver halide solvent, toning agents, hardeners, antifoggants, chemical sensitizers, spectral sensitizers and desensitizers through the coupling reaction with the oxidized product of the developing agent. In the light-sensitive material, auxiliary layers such as filter layer, antihalation layer and anti-irradiation layer can be provided. In these layers and/or emulsion layers, a dye which flows out from the light-sensitive material or bleached during developing processing may be also contained.

[0125] In the light-sensitive material, formalin scavenger, fluorescent brightener, matte agent, lubricant, image stabilizer, surfactant, anti-color foggant, developing accelerator, developing retarder or bleaching accelerator can be added.

[0126] For the support, papers laminated with polyethylene, etc., polyethylene terephthalate film, baryta film, cellulose triacetate, etc. can be used.

[0127] The light-sensitive material of the present invention is particularly useful as the negative-type light-sensitive material.

[0128] For obtaining a dye image by use of the light-sensitive material of the present invention, after exposure, color photographic processings generally known in the art can be performed.

EXAMPLES

[0129] The present invention is described in more detail by referring to Examples.

[0130] Prior to Examples, the silver halide emulsions to be used in Examples were prepared.

Preparation of monodispersed emulsion

[0131] Into a reaction kettle in which an aqueous gelatin solution had been thrown, while controlling the pAg and the pH in the reaction kettle and also controlling the addition time, were added at the same time an aqueous silver nitrate solution, an aqueous potassium iodide solution and an aqueous potassium bromide solution, and then precipitation and desalting were practiced by use of a pH coagulatable gelatin, followed by addition of gelatin to prepare a seed emulsion. The emulsion obtained is called NE-1.

[0132] Also, a seed emulsion NE-2 was prepared in the same manner as described above except for adding K₃RhCI₆ in the reaction kettle. The emulsions and their contents are shown in Table 1.

[0133] In a reaction kettle in which the above seed emulsion and an aqueous gelatin had been added, while controlling the pAg and the pH in the reaction kettle, were added an aqueous ammoniacal silver ntirate solution, an aqueous potassium iodide solution and an aqueous potassium bromide solution in proportion to the surface area during the grain growth, followed by subsequent addition in place of the aqueous potassium bromide solution at an adequate grain size. After precipitation and desalting were practiced similarly as in the case of the seed emulsion, gelatin was added to effect re-dispersion to give an emulsion having a pAg of 7.8 and a pH of 6.0.

[0134] Thus, silver iodobromide emulsions EM-1 to EM-4 with high iodine contents internally of grains were prepared.

[0135] The emulsions and their contents are shown in Table 2.

Example 1

Preparation of Sample No. 101 (Comparative)

[0136] On a cellulose acetate support applied with subbing treatment was prepared multi-layer color light-sensitive materials No. 101 to No. 105 with an overlayed constitution comprising the compositions shown below.

[0137] The amounts coated are indicated in the amount represented in g/m² unit calculated on silver for silver halide and colloidal silver, the amount represented in g/m² unit for the additives and gelatin, and further in moles per mole of silver halide within the same layer for the sensitizing dye, coupler and DIR compound. The emulsion contained in each color sensitive emulsion layer was applied with optimum sensitization with sodium thiosulfate and chloroauric acid.

Sensitizing dye I

Sensitizing dye II

Sensitizing dye III

Sensitizing dye IV

Sensitizing dye V

[0138] In the following description, the respective layers with the above compositions are referred to under the abbreviations indicated such as HC, IL-1, R-1, R-2, IL-2, G-1, G-2, YC, B-1, B-2, Pro-1 and Pro-2.

[0139] In the respective layer, in addition to the above components, surfactants were added as the coating aid, and in G-1, G-2, YC, B-1, B-2 and Pro-1 were added the formalin scavengers shown in Table 3.

Preparation of Samples No. 106 to No. 110 (Present invention)

[0140] Samples No. 106 to 110 were prepared in the same manner as Sample No. 101 except for omitting G-2, changing the emulsion contained in G-1 to a mixture of equal moles of EM-1 and EM-2, further increasing the amounts used of the emulsion, gelatin and TCP contained in G-1 by 30 %, and adding the formalin scavengers shown in Table 3 in G-1, YC, B-1, B-2 and Pro-1 (the amounts of the sensitizing dye, coupler and DIR compound per one mole of silver halide in G-1 are the same as in Sample No. 101).

Preparation of Samples No. 111 to No. 115 (Present invention)

[0141] Samples No. 111 to 115 were prepared in the same as Sample No. 106 except for changing the emulsion contained in G-1 to the emulsions shown in Table 3, and adding the formalin scavengers shown in Table 3 in G-1, YC, B-1, B-2 and Pro-1.

Preparation of Samples No. 116 and No. 117 (Comparative)

[0142] Sample No. 116 was prepared in the same manner as Sample No. 105 except for changing the couplers M-18 and CM-1 contained in G-1 and G-2 to the pyrazolotriazole type magenta coupler MC-1 shown below.

[0143] Sample No. 117 was prepared in the same manner as Sample No. 110 except for changing the couplers M-18 and CM-1 contained in G-1 to the pyrazolotriazole type magenta coupler MC-1 shown below.

[0144] The contents of the respective samples are shown in Table 3.

[0145] The amount of the formalin scavenger added is the total of the amounts added in the respective layers.

[0146] The emulsion in Samples No. 111 to No. 114 is an equimolar mixture of EM-2 and EM-3.

[0147] Each sample was divided into two, and gradation stability under formalin gas atmosphere was evaluated. One of the samples divided into two was applied with the following treatment 1, and the other with the following treatment 2.

Treatment 1

[0148] The sample is maintained in a closed vessel, in which a liquid containing 300 cc of an aqueous 35 % glycerine solution was placed at the bottom and the air equilibrated therewith is filled, at 30 °C for 3 days.

Treatment 2

[0149] The sample is maintained in a closed vessel, in which a liquid containing 6 cc of an aqueous 40 % formaldehyde per 300 cc of an aqueous 35 % glycerine solution was placed at the bottom and the air equilibrated therewith is filled, at 30 °C for 3 days.

[0150] Then, wedge exposure was effected in conventional manner, and the developing processing shown below was applied.

[0151] Compositions of the processing solutions used in the respective processing steps are shown below.

[0152] Thus, gradation stabilities of the sample applied with Treatment 1 (not contacted with formalin gas) and the sample applied with Treatment 2 (contacted with formalin gas) were evaluated (the evaluation method is described below).

[0153] The results of the green-sensitive layer are shown in Table 4.

[0154] Next, Samples No. 101 to No. 117 were each divided into two, of which a part was subjected to wedge exposure-developing processing as described above and the other part was subjected to wedge exposure and then to developing processing in the same manner as described above except for changing the pH of the color developing solution in the above processing steps to 10.5, followed by evaluation of gradation stability similarly as described above. The results of the green-sensitive layer are shown in Table 4.

[0155] The evaluation method of gradation stability is to be described by use of the drawing.

[0156] Fig. 1 shows the chracteristic curve which is the standard (broken line) and the characteristic curve (solid line) to be evaluated. Fig. 2 shows the point gamma values of the respective exposure points from the exposure point which gives a density of the minimum density + 1 in Fig. 1 to the exposure point of Alog H = + 3.0 (Δlog H = 0.15 between the respective exposure points). From Fig. 2, the absolute values Δγ of the difference of the point gamma value at the respective exposure points of the characteristic curve which is the standard and the characteristic curve to be evaluated are determined. Then, the gradation stability is represented by the mean value of Δγ multiplied by 1000 (Δ-γ) and value of E of the standard deviation a of Δγ multiplied by 1000. Thus, the difference in point gamma between the both characteristics is greater as the value of Δγ is greater, and the gradation change is not uniform indicating poor gradation stability as the value of Σ is greater.

[0157] As is apparent from Table 4, it can be understood that the samples of the present invention were found to have good gradation stability with little fluctuation of gradation from the highlight to the shadow of the characteristic curve to storage under formalin gas atmosphere and fluctuations of processing.

[0158] The samples by use of pyrazolotriazole type coupler (No. 116 and No. 117), although the gradation stability under formalin gas atmosphere is at satisfactory level, are remarkably inferior in gradation stability to processing fluctuations.

[0159] Also, in the pyrazolotriazole type coupler, no marked improvement of gradation stability could be recognized even if the green-sensitive layer may be made a single layer. Whereas, when a 5-pyrazolone type coupler is used, by making the green-sensitive layer a single layer, gradation stability under formalin gas condition and the gradation stability to processing fluctuations were markedly improved. This fact was also unexpected to the present inventors.

[0160] Also, in the samples of the present invention, the samples containing emulsions doped with Rh ions internally of the grains (No. 111 to No. 115) were found to be preferred, because the grain size distribution of the silver halide grains in the green-sensitive layer is narrow to give a great improvement effect for processing fluctuations. Further, the sample No. 115 is also preferable with respect to production efficiency, since physical aging and chemical aging can be effected at one time respectively.

[0161] Also, the effects of the present invention could be recognized in the respective samples by use of M-21, M-19, M-22, M-32 or M-3 in place of the coupler (M-18) in Sample No. 106.

[0162] Also, in the respective samples by use of S-28 or S-30 in place of the formalin scavenger of Sample No. 111, the effects of the present invention could be recognized.

[0163] Also, the effects of the present invention could be recognized in the respective samples in which the DIR compound D-42 in B-2 of Sample No. 106 was replaced with D-4 or D-29, the respective samples in which the DIR compound D-26 in G-1 of Sample No. 113 with D-2, D-6 or D-10, the respective samples in which the DIR compound 23 in R-1 of Sample No. 115 is replaced with D-17, D-19 or D-21.

[0164] Also, in the respective samples by use of seed emulsions prepared by addition of RuCl₃, OsCl₃, Pb-(N0₃)₂ in place of K₃RhC1₆ in place of NE-2 as substitute for EM-3 in Samples No. 111 to No. 114 and EM-4 in Sample No. 115, the effects of the present invention could be recognized.

[0165] Each sample used in this Example had exposure latitude (Δlog H) of 3.0 or more.

[0166] As is apparent from the above results, a light-sensitive silver halide color photographic material having excellent gradation stability even when placed under formalin gas atmosphere and also to fluctuations in processing conditions could be provided.

Claims

1. A light-sensitive silver halide color photographic material, comprising on a substrate material at least silver halide emulsion layers which are respectively blue-sensitive, green-sensitive and red-sensitive. wherein said material has a DIR compound, contains a formalin scavenger, and also at least said green-sensitive emulsion layer is constituted of a single layer and contains a 5-pyrazolone type magenta coupler.

2. A light-sensitive silver halide color photographic material according to Claim 1, wherein said single layer constitution means the case when a plurality of emulsion layers which are the same in color sensitivity, being the same in the kind of the couplers contained in the emulsion layers, grain sizes of the silver halide grains, the halogen compositions and crystal habits, and the ratio of the coupler to the silver halide, are arranged as continuous layers.

3. A light-sensitive silver halide color photographic material according to Claim 1, wherein said blue-sensitive layer and said green-sensitive layer are single layers.

4. A light-sensitive silver halide color photographic material according to Claim 1, wherein said all of the blue-sensitive, green-sensitive and red-sensitive silver halide emulsion layers are single layers.

5. A light-sensitive silver halide color photographic material according to Claim 1, wherein said formalin scavenger is a compound represented by the following formula:

wherein R₁ and R₂ each represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an acyl group, a carbamoyl group, an iminomethyl group or an amino group, said respective groups including those having substituents, being also inclusive of those wherein R₁ and R₂ form rings, and when R₁ and R₂ form no ring, at least one of these R, and R₂ is an acyl group, a carbamoyl group or an amino group; and A represents

6. A light-sensitive silver halide color photographic material according to Claim 5, wherein said formalin scavenger is a compound represented by the following formula (S-I), (S-II), (S-III) or (S-IV).







wherein R₃ represents a divalent alkyl group, R⁴, Rs and R₇ represent a hydrogen atom, an alkenyl gorup, an alkyl group or

(where R is an alkyl group), R6 represents a hydrogen atom, an alkyl group or an amino group, and Rg represents an alkyl group, the respective groups including those having substituents; R₄ and Rs, and R₇ and Rg include those which form rings; RB represents a carbonyl group or -C( = NH)- group; R₁₀ represents a hydrogen atom, an alkyl group, a cyclohexyl group, a phenyl group, an aralkyl group, an alkoxyl group, an aryloxy group, a carbamoyl group, an alkoxycarbonyl group or a cyano group; and R₁₁ represents a hydrogen atom, an alkyl group, a cyclohexyl group, a phenyl group, an aralkyl group, a heterocyclic residue, a benzoyl group, a sulfonalkyl group, a sulfonaryl group, a carboxyalkyl group, a carbamoyl group or a thiocarbamoyl group.

7. A light-sensitive silver halide color photographic material according to Claim 5, wherein an amount of said formalin scavenger is 5 x 10-⁵ mole to 1 mole per 1 m² of the light-sensitive silver halide color photographic material.

8. A light-sensitive silver halide color photographic material according to Claim 7, wherein an amount of said formalin scavenger is 1 x 10^-4 mole to 5 x 10^-1 mole per 1 m² of the light-sensitive silver halide color photographic material.

9. A light-sensitive silver halide color photographic material according to Claim 8, wherein an amount of said formalin scavenger is 5 x 10-³ mole to 1 x 10^-1 mole per 1 m² of the light-sensitive silver halide color photographic material.

10. A light-sensitive silver halide color photographic material according to Claim 1, wherein said pyrazolone type magenta coupler is a compound represented by the following formula:

wherein Cp represents a pyrazolone type coupler residue, represents a coupling position of the coupler, X represents a hydrogen atom or a group which is eliminated when a dye is formed through the coupling reaction with an oxidized product of an aromatic primary amine color developing agent.

11. A light-sensitive silver halide color photographic material according to Claim 10, wherein said X is a monovalent group selected from the group consiting of a halogen atom, an alkoxy group, an aryloxy group, a heterocyclicoxy group, an acyloxy group, an alkylthio group, an arylthio group, a heterocyclicthio groups,

(where X in the formula represents a monovalent group selected from the group consisting of a nitrogen atom or a group of atoms necessary for formation of a 5- to 6-membered ring together with at least one atom selected from a carbon atom, an oxygen atom, a nitrogen atom and a sulfur atom), an acylamino gorup and a sufonamide group, and a divalent group of an alkylene group, and the case of a divalent group, X forms a dimer.

12. A light-sensitive silver halide color photographic material according to Claim 10, wherein said pyrazolone type magenta coupler is represented by the following formulae (M-1) and (M-2):



wherein R₂ represents a hydrogen atom or a substituent, R₃ represents a substituent, X has the same meaning as X in the formula (I), L represents 1 to 5, and when t is 2 or more, the respective R_z's may be either the same or different.

13. A light-sensitive silver halide color photographic material according to Claim 12, wherein said substituent represented by R₂ is selected from the group consisting of halogen atoms, an alkyl group, a cycloalkyl group, an aryl group or a heterocyclic group, bonded directly or through a divalent atom or group.

14. A light-sensitive silver halide color photographic material according to Claim 10, wherein an amount of the magenta coupler is 2 x 10-⁵ to 1 x 10-³ mole/m².

15. A light-sensitive silver halide color photographic material according to Claim 14, wherein an amount of the magenta coupler is 5 x 10-⁵ to 1 x 10-³ mole/m².

16. A light-sensitive silver halide color photographic material according to Claim 1, wherein said layer having single layer constitution contains at least two kinds of silver halide grains having different mean grain sizes.

Drawing