EP0327274B1

EP0327274B1 - Light-sensitive silver halide photographic material

Info

Publication number: EP0327274B1
Application number: EP19890300813
Authority: EP
Inventors: Hirokazu Sato; Akiyoshi Tai
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 1988-01-30
Filing date: 1989-01-27
Publication date: 1995-11-15
Anticipated expiration: 2009-01-27
Also published as: DE68924790D1; JPH01196042A; JP2767422B2; EP0327274A3; EP0327274A2; DE68924790T2

Description

This invention relates to a light-sensitive silver halide photographic material with little color turbidity and excellent color reproducibility.
In general, a light-sensitive silver halide color photographic material has three kinds of silver halide emulsion layers for photography. These are each spectrally sensitized selectively so as to be sensitive to blue light, green light and red light. They are each coated on a support. For example, in a light-sensitive silver halide photographic material for color printing paper, a red-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer and a blue-sensitive silver halide emulsion layer are generally provided by coating, and further an intermediate layer or a protective layer, including an UV-ray absorbing layer are also provided.
In a multiple layer light-sensitive color photographic material, the reaction rate between the diffusion-resistant couplers contained in each light-sensitive silver halide emulsion layer with a color developing agent's oxidized product is generally different between the respective emulsion layers. For this reason, excessive oxidized product of the color developing agent generated in an emulsion layer containing a diffusion-resistant coupler with small reaction rate will diffuse to other silver halide emulsion layers. Thus color turbidity is likely to occur and color reproducibility will be lowered.
As means of preventing such color turbidity, there are known techniques in which compounds which deactivate the oxidized product of color developing agent such as hydroquinone derivatives, aminophenol derivatives, gallic acid derivatives, ascorbic acid derivatives, etc. are contained in the intermediate layer as disclosed in U.S. Patents 2,360,290, 2,336,327, 2,403,721, 2,418,613, 2,675,314, 2,701,197, 2,704,713, 2,728,659, 2,732,300, 2,735,765, Japanese Unexamined Patent Publications Nos. 92988/1975, 92989/1975, 93928/1975, 110337/1975, 146235/1977, Japanese Patent Publication No. 23813/1975. However, improvement of color turbidity effected by these is not yet satisfactory, particularly with color turbidity in another layer in the region with a higher color formed density, further improvement has been desired.
On the other hand, in recent years, in this field of art, it has also been desired to have a light-sensitive silver halide color photographic material which can be rapidly processed.
Light-sensitive silver halide color photographic materials are subjected to automatic developing by a machine provided in laboratories. By way of an improvement of service for customers, there have been demands to perform development processing and return the processed product within the same day that the development was ordered. Recently, there have been further demands to return the product within several hours from the order. Thus development of a light-sensitive silver halide color photographic material capable of rapid processing has been increasingly desired.
In response to the demands for such rapid processing, there has been developed the technique of reducing the silver bromide content as described in Japanese Unexamined Patent Publication No. 184142/1983, Japanese Patent Publication No. 18939/1981. Further, it is also known that a high chloride silver halide emulsion (which means silver halide containing 80 mol% or more of silver chloride) is capable of rapid processing.
However, there is also the problem that the tendency to increased color turbidity is more marked when a light-sensitive silver halide color photographic material having a high chloride silver halide emulsion layer is subjected to an ultra-rapid color development processing method with a color developer containing no bromide. Improvement of this problem is also required.
The present invention has been accomplished in view of the state of the art as described above. The object of the present invention is to provide a light-sensitive silver halide color photographic material having little color turbidity and excellent color reproducibility.
This object has been accomplished by a particular light-sensitive silver halide photographic material comprising at least two light-sensitive silver halide emulsion layers containing diffusion-resistant couplers and at least one non-light-sensitive intermediate layer sandwiched between them, all provided on a support. This non-light-sensitive intermediate layer contains a compound which deactivates the oxidized product of a color developing agent. The relative color formation speed ratio k₁/k₂ (wherein k₁ is less than or equal to k₂) between the diffusion-resistant couplers contained in the respective two light-sensitive silver halide emulsion layers adjacent to said non-light-sensitive intermediate layer (wherein k₁ and k₂ are each the absorbances at the maximum absorption wavelength in the visible region of colour dyes extracted into a mixture of methanol and ethyl acetate (present in a volume ratio of 1:2 respectively, based on the volume of the reaction mixture), said dyes being formed from mixing a coupler solution A (wherein the respective diffusion resistant coupler is dispersed by use of 0.5 g of dioctyl phthalate per 1 mmol of coupler and the coupler concentration is 2 x 10⁻² mol and silver chloride concentration is 4 x 10⁻³ mol using a silver chloride emulsion with an AgCl content of 100 % and an average particle size of 0.14µm) and a color developer B (comprising 2 x 10⁻² mol of the colour developer which will be used to develop said light-sensitive silver halide material, 40g/liter of anhydrous potassium carbonate, 1g/liter of sodium sulfite, and having pH 10.0) at 25°C at a volume ratio of 1:1 (coupler solution A: color developer B)) is 0.25 ≦ k₁/k₂ ≦ 1, and the relationship of said k₁/k₂ to the ability to deactivate the oxidized product of the color developing agent in the non-light-sensitive layer Sc is represented by Formula (I): $Sc .k₁/k₂≧0.2$

wherein Sc is represented by: $Sc = \frac{{(ABS)}_{R}}{{(ABS)}_{S}} x Cs$

wherein the units of Sc are millimoles/m² and Cs represents the amount in mmol of the compound which deactivates the oxidized product of the color developing agent contained per square meter of the non-light-sensitive intermediate layer, (ABS)_R is an absorbance measured in the same way as k₁ or k₂ except that the coupler used is a coupler of the formula (C-1):

and (ABS)_S is an absorption obtained in the same way as (ABS)_R, except that a dispersion prepared by use of 0.5g of dioctyl phthalate and per 1 mmol of the said compound which deactivates the oxidised product of the color developing agent is added to coupler solution A (concentration of the compound which deactivates the oxidized product of the color developing agent: 2·10⁻³ mol).
The relative color formation speed of a coupler, for example as described in Japanese Unexamined Patent Publication No. 60437/1984, can be determined by adding a mixture of two different dyes which can be separated from each other into an emulsion and measuring the amounts of the respective dyes obtained by color developing the emulsion.
However, since this method employs a magenta coupler as the standard for the cyan coupler, and a cyan coupler as the standard for the magenta coupler and the yellow coupler, it is difficult to determine a united standard.
The relative color formation speed ratio k₁/k₂ between the diffusion-resistant couplers used in the present invention is determined as described below on the basis of a principle which is basically similar to the above method.
A coupler is dispersed by use of 0.5 g of dioctyl phthalate per 1 mmol of coupler. In the dispersion are mixed a coupler solution A (wherein the coupler concentration is 2 x 10⁻² mol and silver chloride concentration is 4 x 10⁻³ mol using a silver chloride emulsion with an AgCl content of 100 % and an average particle size of 0.14 µm) and a color developer B (comprising 2x10⁻² mol of N-ethyl-N-β-methanesulfonamidoethyl-3-methyl-4-aminoaniline sulfate, 40g/liter of anhydrous potassium carbonate, 1g/liter of sodium sulfite, and having pH 10.0) at 25 °C at a volume ratio of 1 : 1 (coupler solution A : color developer B). After the color forming reaction, 1/2-fold volume of methanol and 1-fold volume of ethyl acetate based on the volume of the mixture were added to extract the color dyes into the organic solvent phase. Absorbance of the extract at the maximum absorption wavelength in the visible region was measured.
The same measurement is performed for both the couplers to be compared, and the ratio of the absorbances obtained is defined as k₁/k₂. In this case, the absorbance k₁ is less than or equal to k₂.
The ability Sc of the compound to deactivate the oxidized product of the color developing agent in the non-light sensitive intermediate layer in the present invention is determined according to the method as described below.
In the above measurement to determine k₁/k₂, when a compound of formula C-1 is used as the coupler, the absorbance obtained is denoted by (ABS)_R.
Then the same measurement is performed under the same conditions as in the above determination of (ABS)_R except that a dispersion prepared by use of 0.5g of dioctyl phthalate per 1 mmol of the compound which deactivates the oxidized product of the color developing agent is added into the above coupler solution A (concentration of the compound which deactivates the oxidized product of the color developing agent is 2 x 10⁻³ mol), and the absorbance obtained is denoted by (ABS)_S. Sc is represented by: $Formula (II) Sc= \frac{{(ABS)}_{R}}{{(ABS)}_{S}} x Cs$

wherein the units of Sc are millimoles/m² and Cs represents amount in mmol of the compound which deactivates the oxidized product of the color developing agent contained per 1 m² of the non-light sensitive intermediate layer.
The diffusion-resistant couplers and compounds which deactivate the oxidised product of a colour developing agent used in the present invention are defined by the above k₁/k₂ and Sc, and are not limited by their chemical structures.
In the present invention, the above ratio k₁/k₂ is required to be 0.25 or more and 1 or less, preferably 0.30 or more and 1 or less. The product of Sc represented by the above formula (I) and k₁/k₂ is required to be 0.2 or more, preferably 0.3 or more.
The light-sensitive silver halide color photographic material of the present invention, preferably contains a hydroquinone type compound as the compound which deactivates the oxidized product of the color developing agent in the non-light-sensitive intermediate layer, and a yellow coupler in one of the two light-sensitive silver halide emulsion layers adjacent to said non-light-sensitive intermediate layer and a magenta coupler in the other of the emulsion layers.
The non-light-sensitive intermediate layer used in the present invention is required to have the ability (Sc) to deactivate the oxidized product of the color developing agent which satisfies the relationship of the above formula (I). Sc can be controlled as desired according to the nature of and amount added of the compound which deactivates the oxidized product of the color developing agent.
The compound which deactivates the oxidized product of the color developing agent used in the present invention, is preferably a hydroquinone derivative, aminophenol derivative, gallic acid derivative, ascorbic acid derivative but, as mentioned above, more preferably a hydroquinone derivative.
The hydroquinone type compounds which deactivate the oxidized product of the color developing agent preferably used in the present invention are represented by the formula (HQ) shown below.
In the formula, R₁ represents a substituted or unsubstituted alkyl group, and n represents an integer of 1 to 3. However, the total sum of carbon atoms in R₁ numbers 8 or more, and when n is 2 or more, R₁ is the same or different. R₂ represents a halogen atom, hydroxyl group, sulfo group, carboxyl group. m represents an integer of 0 to 3, and when m is 2 or more, R₂ is the same or different. The sum of n + m is 4 or less.
In the above formula (HQ), the alkyl group represented by R₁ is preferably a straight or branched chain alkyl group having 1 to 20 carbon atoms, including, for example, methyl, ethyl, propyl, t-butyl, octyl, t-dodecyl groups. Examples of substituents for R₁ include a sulfo group, carboxyl group, cyano group, hydroxyl group, halogen atom (e.g. fluorine, chlorine, bromine), -COOR₄, -COR₅, -OR₆, -SO₂R₇, -NHSO₂R₈. Here, R₄, R₅, R₆, R₇ and R₈ represent an alkyl group, alkenyl group, cycloalkyl group, or aryl group.
Further, the alkyl group represented by R₄ through R₈ is preferably the same as the alkyl represented by the above R₁. Examples of cycloalkyl groups include cyclopentyl, cyclohexyl groups. For the alkenyl group one having 2 to 18 carbon atoms is preferred, for example allyl, octenyl, octadecenyl groups. Examples of the aryl groups include phenyl, naphthyl groups. R₄, R₅, R₆, R₇ and R₈ are optionally substituted.
R₂ in the formula (HQ) represents a halogen atom (e.g. fluorine, chlorine, or bromine), hydroxyl group, sulfo group, carboxyl group, preferably a sulfo group or a carboxyl group.
n is preferably 1 or 2, and m is preferably 0 or 1.
In the following, representative specific examples of the compounds which deactivate the oxidized product of the color developing agent to be used in the present invention are listed.
The compounds which deactivate the oxidized product of the color developing agent to be used in the present invention may include in addition to the above compounds, for example, those as described in U.S. Patents 2,360,290, 2,336,327, 2,418,613, 2,673,314, 2,701,197, 2,704,713, 2,728,659, 2,732,300, 2,735,765, Japanese Unexamined Patent Publications. Nos. 92988/1975, 92989/1975, 93928/1975, 110337/1975, 146235/1977, Japanese Patent Publication No. 23813/1975, Japanese Unexamined Patent Publications Nos. 24141/1983, 5247/1984, 81639/1987 and further Japanese Unexamined Patent Publication No. 39851/1987, page 5 right lower col. to page 7 right lower col, and Japanese Unexamined Patent Application No. 93538/1986, page 19 to page 29. They can be synthesized easily according to the methods as described in the above patents.
The compound which deactivates the oxidized product of the color developing agent to be used in the present invention can be used either singly or in combination, Sc in this latter case is determined as the sum of the Sc's for the respective compounds. In the case of the hydroquinone type compound, it is also possible to add a quinone type compound which is its oxidized product.
The compound which deactivates the oxidized product of the color developing agent may be contained in the non-light-sensitive intermediate layer used in the present invention preferably in an amount of 2 x 10⁻⁴ to 1 x 10⁻² mol per 1 m², more preferably 3 x 10⁻⁴ to 5 x 10⁻³ mol.
The compound which deactivates the oxidized product of the color developing agent to be used in the present invention, can be added in the coating solution for forming the layer or in a solution dissolved at an appropriate concentration in a solvent which does not deleteriously affect the light-sensitive material such as water, alcohol. There can also be preferably employed a method in which it is dissolved in a high boiling organic solvent and/or a low boiling organic solvent, followed by emulsification into an aqueous solution before addition.
The yellow coupler preferably used in the present invention is preferably represented by the following formula (Y).
In the formula, R_Y1 represents a halogen atom. R_Y2 represents a hydrogen atom or a group substitutable on the benzene ring, and B represents a ballast group. Z represents a hydrogen atom, a halogen atom or a group which is eliminated in a reaction with the oxidized product of the color developing agent.
In the above formula (Y), the halogen atom represented by R_Y1 is preferably chlorine atom, and R_Y2 is preferably a hydrogen atom.
In the above formula (Y), examples of the ballast group represented by B include acylamino, alkoxycarbonyl, aryloxycarbonyl, alkylsulfamoyl, arylsulfamoyl, alkylsulfonamide, arylsulfonamide, alkylureido, arylureido, succinimido, alkoxy, aryloxy, alkoxycarbonylamino, alkylcarbamoyl, arylcarbamoyl, alkylsulfamoylamino, arylsulfamoylamino, alkyl, alkenyl, acyloxy. It is particularly preferably a group having a total number of carbon atoms of 8 to 30.
In the above formula (Y), Z is preferably a halogen atom or the group which is eliminated in a reaction with the oxidized product of the color developing agent. As the halogen atom, chlorine atom is preferable, and the group which is eliminated is preferably a group represented by

(wherein R_Z1 represents a group of non-metal atoms necessary for forming an optionally substituted nitrogen-containing heterocyclic ring) or -OR_Z2 (wherein R_Z2 represents a substituted or unsubstituted alkyl group, aryl group or heterocyclic group).
In the present invention, a yellow coupler containing at least one functional group A shown below in at least one of the groups represented by B and Z in the above formula (Y) is most preferably used.
Functional group A:
-COOH, -OH, -SO₂R¹, -SOR², -COOR³, -OCOR⁴,

Here, R¹ - R⁴, R⁶, R⁷ and R¹⁰ each represent an alkyl group or an aryl group, R⁵, R⁸, R⁹ and R¹¹ each represent a hydrogen atom, an alkyl group or an aryl group.
In the groups denoted by the functional group A, the alkyl group represented by R¹ to R¹¹ is preferably a straight or branched alkyl group having 1 to 20 carbon atoms. The aryl group represented by R¹ to R¹¹ is preferably phenyl group. Both the alkyl group and the aryl group represented by R¹ to R¹¹ are optionally substituted. The functional group A is contained in at least one of the groups represented by B and Z, but particularly preferably in the group represented by B.
In the following, representative specific examples of the yellow coupler to be used in the present invention are enumerated, but the present invention is not limited by these.
The yellow coupler to be used in the present invention also includes, in addition to the above compounds, the yellow couplers as described in Japanese Unexamined Patent Publications Nos. 155538/1982, 6652/1986, 70841/1980, 24321/1972, 66834/1973, Japanese Patent Publication No. 19031/1971, Japanese Unexamined Patent Publications Nos. 87650/1975, 123342/1975, U.S. Patent 3,408,194, and further Japanese Unexamined Patent Publication No. 72239/1986, page 5 left lower col. to page 8 left upper col., Japanese Patent Applications Nos. 231525/1986, page 22 to page 40, 243865/1986, page 20 to page 38. They are also optionally synthesized according to the methods described in these documents.
In the present invention, known 5-pyrazolone type couplers and pyrazoloazole type couplers can be preferably used as the magenta coupler. More preferably, they are couplers represented by the following formulae (M-I) to (M-III).
In the formula, Ar represents an aryl group, R_P1 hydrogen atom or a substituent and R_P2 represents a substituent. Y represents hydrogen atom or a group which is eliminated in the reaction with the oxidized product of the color developing agent, W represents -NH-, -NHCO- (N atom is bonded to the carbon atom of the pyrazolone nucleus) or -NHCONH-, m is an integer of 1 or 2.
In the formulae, X_M represents hydrogen atom or a group which is eliminated in the reaction with the oxidized product of the color developing agent, each of R_M1 and R_M2 represents hydrogen atom or a substituent.
In the above formula (M-I), the aryl group represented by Ar is preferably a phenyl group, more preferably a phenyl group substituted by at least one halogen atom, alkyl group, alkoxy group, alkoxycarbonyl group, acylamino group or cyano group.
The substituent represented by R_P1 is preferably a halogen atom or an alkoxy group, more preferably a chlorine atom. The substituent represented by R_P2 is not particularly limited, but at least one of R_P2 is a ballast group. As the ballast group represented by R_P2, known ballast groups in this field of art are preferably used. W is preferably -NH-.
In the above formula (M-I), the group which is eliminated in the reaction with the oxidized product of the color developing agent represented by Y is preferably aryloxy, alkoxy, heterocyclicoxy, silyloxy, phosphoneoxy, alkylthio, arylthio, heterocyclicthio, acylthio, thiocyano, aminothiocarbonylthio, acylamino, sulfonamide, alkoxycarbonylamino, aryloxycarbonylamino or nitrogen-containing heterocyclic group bonded through nitrogen atom at the active site of the pyrazolone ring.
In the above formulae (M-II) and (M-III), the substituents represented by R_M1 and R_M2 are not particularly limited, but are preferably alkyl, aryl, anilino, acylamino, sulfonamide, alkylthio, arylthio, alkenyl, cycloalkyl, halogen atoms and cycloalkenyl, alkynyl, heterocyclic ring, sulfonyl, sulfinyl, phosphonyl, acyl, carbamoyl, sulfamoyl, cyano, alkoxy, aryloxy, heterocyclicoxy, siloxy, acyloxy, carbamoyloxy, amino, alkylamino, imide, ureido, sulfamoylamino, alkoxycarbonylamino, aryloxycarbonylamino, alkoxycarbonyl, aryloxycarbonyl, heterocyclicthio groups, and also spiro compound residues, or bridged hydrocarbon compound residues.
Most preferred as the substituent R_M1 on the above heterocyclic ring is one represented by the formula (M-IV) shown below.

wherein R_M4, R_M5 and R_M6 have the same meanings as the above R_M1 and R_M2.
Also, two of R_M4, R_M5 and R_M6, for example, R_M4 and R_M5 may be bonded together to form a saturated or unsaturated ring (e.g. cycloalkane, cycloalkene, heterocyclic ring), and further R_M6 may be bonded to said ring to constitute a bridged hydrocarbon compound residue.
Of the compounds of the formula (M-IV) preferred are the ones where (i) at least two of R_M4 to R_M6 are alkyl groups and (ii) one of R_M4 to R_M6 (for example, R_M6) is a hydrogen atom, and the other two (R_M4 and R_M5) are bonded together to form a cycloalkyl together with the root carbon atom.
Further, preferable of (i) is the case wherein two of R_M4 - R_M6 are alkyl groups, and the other one is a hydrogen atom or an alkyl group, and most preferred is the case wherein all of R_M4 to R_M6 are alkyl groups.
Examples of the group which is eliminated in the reaction with the oxidized product of the color developing agent represented by X_M in the formulae (M-II) and (M-III) include halogen atoms (chlorine, bromine, or fluorine) and alkoxy, aryloxy, heterocyclicoxy, acyloxy, sulfonyloxy, alkoxycarbonyloxy, aryloxycarbonyl, alkyloxalyloxy, alkoxyoxalyloxy, alkylthio, arylthio, heterocyclicthio, alkyloxythiocarbonylthio, acylamino, sulfonamide, nitrogen-containing heterocyclic ring bonded through the N-atom, alkyloxycarbonylamino, aryloxycarbonylamino, carboxyl groups; preferably halogen atoms, particularly preferably chlorine atom.
Also, the above magenta coupler may also form a polymer dimer or higher through Y, Ar, R_P1 or R_P2 in the above formula (M-I), and through X_M, R_M1 or R_M2 in the above formulae (M-II) and (M-III).
In the following, representative specific examples of the magenta coupler to be used in the present invention are enumerated, by which the present invention is not limited.
The magenta couplers to be used in the present invention include, in addition to the above compounds, those disclosed in U.S. Patent 3,684,514, U.K. Patent 1,183,515, Japanese Patent Publications Nos. 6031/1965, 6035/1965, 15754/1969, 40757/1970, 19032/1971, Japanese Unexamined Patent Publications Nos. 13041/1975, 129035/1978, 37646/1976, 62454/1980, U.S. Patent 3,725,067, U.K. Patents 1,252,418, 1,334,515, Japanese Unexamined Patent Publications Nos. 171956/1984, 162548/1984, 43659/1985, 33552/1985, 39852/1987, Research Disclosure No. 24626 (1984), Japanese Unexamined Patent Publications Nos. 120147/1986, 120148/1986, 120149/1986, 120152/1986, 230146/1986, 230147/1986, Japanese Patent Application No. 9791/1986. They can be synthesized according to the methods described in these documents.
The light-sensitive silver halide photographic material of the invention can be applied to, for example, color negative and positive film, as well as color printing paper. Above all the effect of the present invention is exhibited when it is applied to a color printing paper to be provided for direct viewing.
The light-sensitive silver halide photographic material, including the color printing paper is a light-sensitive silver halide photographic material for multi-color use, and for effecting color reproduction by the color subtractive method. It generally has a structure (in addition to the one already defined) comprising silver halide emulsion layers containing the respective couplers of magenta, yellow and cyan laminated in a suitable number of layers and order of layers on a support. The number of layers and their order may be suitably changed depending on the desired performance, and purpose of use.
As the yellow coupler, couplers of the above formula (Y) are preferred, and as the magenta coupler, couplers represented by the above formulae (M-I) to (M-III) are preferably used.
As the cyan coupler, phenol type compounds, naphthol type compounds can be used.
In the present invention, hydrophobic compounds such as couplers, and/or compounds which deactivate the oxidized product of the color developing agent can optionally be added into the light-sensitive silver halide photographic material by use of various methods for example, the solid dispersion method, the latex dispersion method, the oil-in-water type emulsification and dispersion method. For example, the oil-in-water type emulsification and dispersion method may be carried out by dissolving a hydrophobic compound such as a coupler generally in a high boiling organic solvent with a boiling point of about 150 °C or higher, or optionally in a low boiling and/or water-soluble organic solvent in combination, emulsifying the solution in a hydrophilic binder such as an aqueous gelatin solution by use of a surfactant, and then adding the emulsion into the desired hydrophilic colloid layer.
The silver halide used in the present invention may be any silver halide, for example silver chloride, silver bromide, silver iodide, silver chlorobromide, silver iodobromide or silver chloroiodide.
However, for light-sensitive silver halide photographic materials in which particularly rapid developability is demanded such as color printing paper, silver halide grains containing 90 mol% or more of silver chloride are preferred, and the silver bromide content is preferably 10 mol% or less and the silver iodide content preferably 0.5 mol% or less. More preferably, silver chlorobromide having a silver bromide content of 0.1 - 2 mol% is employed.
The silver halide grains are used either alone or as a mixture with other silver halide grains having a different composition. Also, they can be used in a mixture with silver halide grains having a silver chloride content of 10 mol% or less.
In the silver halide emulsion layer preferably containing silver halide grains having a silver chloride content of 90 mol% or more, the ratio of the silver halide grains having a silver chloride content of 90 mol% to the total number of silver halide grains contained in said emulsion layer is preferably 60 % by weight or more, more preferably 80 % by weight or more.
The composition of the silver halide grain is either uniform from the inner portion to the outer portion of the grain, or different in the inner portion from the outer portion. When the compositions in the inner portion and the outer portion of the grain are different, the composition is either varied continuously or discontinuously.
The grain size of the silver halide grain is not specifically limited, but it is preferably within the range of 0.2 to 1.6 µm, more preferably 0.25 to 1.2 µm, taking into account photographic performances such as rapid processability and sensitivity. The above grain size can be measured according to methods generally employed in the related field of art. Representative methods are described in Rabland "Grain Size Analytical Method" (A.S.T.M. Symposium on Light Microscopy, 1955, pp. 94 - 122) or "Theory of Photographic Process" (Mees and James, co-authors, third edition, McMillan Co., 1966, Chapter 2).
For example, the grain size can be measured by use of the projected area or from an approximate value for the diameter of the grains. When the grain is substantially uniform in shape, the grain size distribution can be represented accurately by the diameter or projected area.
The distribution of the grain sizes of silver halide grains is either poly-dispersed or mono-dispersed. Preferably, mono-dispersed silver halide grains having a fluctuation coefficient of 0.22 or less, more preferably 0.15 or less, in the grain size distribution of the silver halide grains is employed. Here, the fluctuation coefficient is a coefficient indicating the breadth of the grain size distribution, which is defined by the following formula: $Fluctuation coefficient (S/ \bar{r}) = \frac{Standard deviation of grain size distribution}{Average grain size}$
$Standard deviation of grain size distribution (S) = \sqrt{\frac{Σ(\bar{r} - ri)²ni}{Σni}}$
$Average grain size (\bar{r}) = \frac{Σniri}{Σni}$
Here, ri represents the grain size of individual grains, ni represents their number. The grain size as mentioned here refers to the diameter of a spherical silver halide grain, or the diameter of a projected image calculated from a circular image having the same area in the case of grains having a cubic shape or a shape other than a sphere.
The silver halide grains to be used can be obtained according to an acidic method, neutral method or ammonia method. Said grains are grown either simultaneously or after preparation of seed grains. The method for making seed grains and the method for growing the grains is either the same or different.
The method of reacting the soluble silver salts with the soluble halogen salts can be a normal mixing method, reverse mixing method, simultaneous mixing method or combinations thereof. It is preferably the simultaneous mixing method. Further, as one mode of the simultaneous mixing method, it is also possible to use the pAg-controlled double jet method as described in Japanese Unexamined Patent Publication No. 48521/1979.
Further, if necessary, a silver halide solvent, for example thioether, is also employed. Also, compounds such as mercapto-containing compounds, nitrogen-containing heterocyclic compounds or sensitizing dyes are also optionally added during formation of silver halide grains or after completion of grain formation. Any shape of silver halide grains can be used. A preferable example is the cubic shape having {100} plane as the crystal surface. Also, grains having octahedral, tetradecahedral, dodecahedral shapes can be made according to the methods as described in U.S. Patents 4,183,756, 4,225,666, Japanese Unexamined Patent Publication No. 26589/1980, Japanese Patent Publication No. 42737/1980, The Journal of Photographic Science (J. Photgr. Sci.), 21, 39 (1973). These can also optionally be used. Further, grains having twin crystal surfaces may also optionally be used.
Silver halide grains comprising either a single shape or a mixture of various shapes are employed.
The silver halide grains to be used in the emulsion can contain metal ions, for example, cadmium salt, zinc salt, lead salt, thallium salt, iridium salt or a complex thereof, rhodium salt or a complex thereof, iron salt or a complex thereof. These are contained either internally and/or on the surface of the grains, either by adding them in the process of forming the grains and/or in the process of growing them. Optionally by placing the grains in an appropriate reducing atmosphere, reducing sensitizing nuclei can be imparted internally of the grains and/or the surface of the grains.
The emulsion containing the silver halide grains has either had unnecessary soluble salts removed after completion of the growth of the silver halide grains, or just contains them. When said salts are to be removed, it can be done by the method described in Research Disclosure No. 17643, for example.
The silver halide grains to be used in the emulsion are either grains in which latent images are formed primarily on the surface or grains in which latent images are formed primarily internally. Preferably, grains in which latent images are formed primarily on the surface are employed.
The emulsion to be used in the present invention is preferably chemically sensitized according to conventional methods. Methods which may be employed are, for example, the sulfur sensitization method which uses a compound containing sulfur which can react with silver ions or active gelatin, the selenium sensitizing method which uses a selenium compound, the reducing sensitizing method which uses a reducing substance, the noble metal sensitizing method which uses gold or other noble metal compounds either individually or in combination.
The silver halide emulsion is optionally optically sensitized to a desired wavelength region by use of a dye known as a sensitizing dye.
In the light-sensitive silver halide photographic material of the present invention, there can optionally be used, as desired, color antifoggant, film hardener, plasticizer, polymer latex, UV-ray absorber, formalin scavenger, mordant, developing accelerator, developing retarder, fluorescent brighener, matting agent, lubricant, antistatic agent, or surfactant.
The light-sensitive silver halide photographic material may be developed by a variety of color developing processes.
The present invention is described in detail in the Examples, but the embodiments of the present invention should not be limited to these.

Example 1

(Preparation of silver halide emulsions)

Six kinds or silver halide emulsions shown in Table 1 were prepared according to a neutral method and a simultaneous mixing method.
Into the respective silver halide emulsions was added after completion of chemical sensitization 1 x 10⁻⁴ mol of STB-1 shown below as the emulsion stabilizer per 1 mol of silver halide.

(Preparation of light-sensitive halide color photographic material sample)

Next, the layers 1 - 7 shown below were successively provided by coating (simultaneous coating) on a paper support coated on the both surfaces with polyethylene to prepare light-sensitive silver halide color photographic materials 1 - 33 (in the following examples, the amount added is shown in an amount per 1 m² of the light-sensitive material).

Layer 1 ...: A layer containing gelatin (1.2 g), 0.29 g (calculated on silver, hereinafter the same) of a blue-sensitive silver halide emulsion (Em-1) and 0.3 g of dinonyl phthalate (DNP) containing 1.0 mmol of yellow coupler shown in Table 2, 0.3 g of photostabilizer ST-1 and 0.015 g of 2,5-dioctylhydroquinone (HQ-1) dissolved therein.
Layer 2 ...: A layer containing gelatin (0.9 g) and 0.2 g of diocryl phthalate (DOP) containing the compound which deactivates the oxidized product of the color developing agent shown in Table 2 dissolved therein.
Layer 3 ...: A layer containing gelatin (1.4 g), 0.2 g of green-sensitive silver halide emulsion (Em-2), 0.3 g of DOP containing 1.0 mmol of magenta coupler shown in Table 2, 0.25 g of the photostabilizer ST-2 and 0.01 g HQ-1 dissolved therein and 6 mg of a filter dye AI-1 shown below.
Layer 4 ...: A layer containing gelatin (1.2 g) and 0.3 g of DNP containing 0.6 g of UV-absorber UV-1 shown below and 0.05 g of HQ-1 dissolved therein.
Layer 5 ...: A layer containing gelatin (1.4 g), 0.20 g of red-sensitive silver halide emulsion (Em-3) and 0.3 g of DOP containing 0.18 g of cyan coupler (C-1), 0.36 g of cyan coupler (C-2), 0.3 g of ST-1 and 0.01 g of HQ-1 dissolved therein.
Layer 6 ...: A layer containing gelatin (1.1 g), 0.2 g of DOP containing 0.2 g of UV-1 dissolved therein and 5 mg of a filter dye AI-2 shown below.
Layer 7 ...: A layer containing gelatin (1.0 g) and 0.05 mg of 2,4-dichloro-6-hydroxy-s-triazine sodium.

After each of the above light-sensitive material samples No. 1 - 33 was exposed to blue light through an optical wedge (by use of an interference filter with a center wavelength of 460 nm), processing was performed following the development processing steps shown below.
After the development processing, the blue light absorption density D'B at the unexposed portion, the blue light absorption density DB at the exposed portion, the green light absorption density D'G at the unexposed portion and the green light absorption density DG at the exposed portion were determined by a densitometer (Sakura Densitometer PDA-60, produced by Konishiroku Photo Industry).
Next, according to the following formula, the ratio (Q) of the blue light absorption density to the green light absorption density excluding the fog density was determined. $Q = \frac{(DG - D′G)}{(DB - D′B)}$
The Q value under the condition where the optical density (D) is DB = 1.0 is made Q₁, and the Q value under the condition of DB = 2.0 is made Q₂. The results are shown in Table 2.

[Processing steps]

Color developing solution recipe

(made up to 1 liter with addition of water, and adjusted to pH 10.0 with sodium hydroxide)

Bleach-fixing solution recipe

(made up to 1 liter with addition of water, and adjusted to pH 7.0 with ammonia water)
It is apparent from Table 2, the samples No. 11 to N. 33 of the present invention having k₁/k₂ and Sc k₁/k₂ within the ranges specified in the present invention have remarkably small Q₁ and Q₂ values compared with the comparative samples. Thus it can be appreciated that color turbidity is effectively prevented and color reproducibility is improved by the invention.

Example 2

Light-sensitive silver halide color photographic material samples No. 34 to 66 were prepared in entirely the same manner as in Example 1 except for replacing the blue-sensitive silver halide emulsion in Layer 1 of the light-sensitive silver halide color photographic material prepared in Example 1 with Em-4 shown in Table 1, the green-sensitive silver halide emulsion in Layer 3 with Em-5 in Table 1, and the red-sensitive silver halide emulsion in Layer 5 with Em-6 in Table 1, respectively and using the yellow coupler, magenta coupler and the compound which deactivates the oxidized product of the color developing agent in Layer 1, Layer 3 and Layer 2, respectively.
Samples obtained were subjected to exposure with blue light similarly as described in Example 1, processed according to the developing processing steps as shown below, followed by the same measurement as described in Example 1. The results are shown in Table 3.

[Processing steps]

[Color developing solution]

(made up to the total amount of 1 liter with addition of pure water, and adjusted to pH 10.2)

[Bleach-fixing solution]

(made up to the total amount of 1 liter with addition of water, and adjusted to pH 5.7 with potassium carbonate or glacial acetic acid)

[Stabilizing solution]

(made up to the total amount of 1 liter with addition of water, and adjusted to pH 7.0 with sulfuric acid or potassium hydroxide)
It is apparent from Table 3, also in the present Examples by use of silver halide emulsions with higher silver chloride content, the preferred effect of the present invention could be obtained. Further, when compared with Example 1, it can be appreciated that the effect of the present invention can be exhibited more remarkably when a silver halide emulsion with a higher silver chloride content is used.

Claims

A light-sensitive silver halide photographic material comprising at least two light sensitive silver halide emulsion layers containing diffusion-resistant couplers and at least one non-light-sensitive intermediate layer sandwiched between said light-sensitive silver halide emulsion layers provided on a support, wherein said non-light-sensitive intermediate layer contains a compound which deactivates the oxidized product of a color developing agent, the relative color formation speed ratio k₁/k₂ (wherein k₁ is less than or equal to k₂) between the diffusion-resistant couplers contained in the respective two light-sensitive silver halide emulsion layers adjacent to said non-light-sensitive intermediate layer (wherein k₁ and k₂ are each the absorbances at the maximum absorption wavelength in the visible region of colour dyes extracted into a mixture of methanol and ethyl acetate (present in a volume ratio of 1:2 respectively, based on the volume of the reaction mixture), said dyes being formed from mixing a coupler solution A (wherein the respective diffusion resistant coupler is dispersed by use of 0.5 g of dioctyl phthalate per 1 mmol of coupler and the coupler concentration is 2 x 10⁻² mol and silver chloride concentration is 4 x 10⁻³ mol using a silver chloride emulsion with an AgCl content of 100 % and an average particle size of 0.14µm) and a color developer B (comprising 2 x 10⁻² mol of the colour developer which will be used to develop said light-sensitive silver halide material, 40g/liter of anhydrous potassium carbonate, 1g/liter of sodium sulfite, and having pH 10.0) at 25°C at a volume ratio of 1:1 (coupler solution A: color developer B)) is 0.25 ≦ k₁/k₂ ≦ 1, and the relationship of said k₁/k₂ to the ability to deactivate the oxidized product of the color developing agent in the non-light-sensitive layer Sc is represented by Formula (I): $Sc .k₁/k₂≧0.2$
wherein Sc is represented by: $Sc = \frac{{(ABS)}_{R}}{{(ABS)}_{S}} x Cs$
wherein the units of Sc are millimoles/m² and Cs represents the amount in mmol of the compound which deactivates the oxidized product of the color developing agent contained per square meter of the non-light-sensitive intermediate layer, (ABS)_R is an absorbance measured in the same way as k₁ or k₂ except that the coupler used is a coupler of the formula (C-1):
and (ABS)_S is an absorption obtained in the same way as (ABS)_R, except that a dispersion prepared by use of 0.5g of dioctyl phthalate per 1 mmol of the said compound which deactivates the oxidised product of the color developing agent is added to coupler solution A (concentration of the compound which deactivates the oxidized product of the color developing agent 2·10⁻³ mol).
The light-sensitive silver halide photographic material according to Claim 1, wherein said relative color formation speed ratio k₁/k₂ is 0.30 ≦ k₁/k₂ ≦ 1.
The light-sensitive silver halide photographic material according to Claim 1 or 2, wherein the relationship of said k₁/k₂ to the ability Sc is represented by Formula (I′): $Sc·k₁/k₂ ≧ 0.3$
The light-sensitive silver halide photographic material according to any one of the preceding claims, wherein said compound which deactivates the oxidized product of a color developing agent is a hydroquinone derivative, aminophenol derivative, gallic acid derivative or ascorbic acid derivative.
The light-sensitive silver halide photographic material according to any one of the preceding claims, wherein said compound which deactivates the oxidized product of a color developing agent is a hydroquinone derivative represented by the formula (HQ):
wherein R₁ represents a substituted or unsubstituted alkyl group, n represents an integer of 1 to 3 with the proviso that the total sum of carbon atoms in R₁ numbers 8 or more, and when n is 2 or more, R₁ is the same or different; and R₂ represents a halogen atom, hydroxyl group, sulfo group, carboxyl group, m represents an integer of 0 to 3, and when m is 2 or more, R₂ is the same or different; and the sum of n + m is 4 or less.
The light-sensitive silver halide photographic material according to Claim 5, wherein the alkyl group represented by R₁ is a methyl, ethyl, propyl, t-butyl, octyl or t-dodecyl group; the substituent possessed by R₁ is a sulfo group, carboxyl group, cyano group, hydroxyl group, halogen atom, -COOR₄, -COR₅, -OR₆, -SO₂R₇ or -NHSO₂R₈; wherein R₄, R₅, R₆, R₇ and R₈ represent an alkyl group, alkenyl group, cycloalkyl group or aryl group.
The light-sensitive silver halide photographic material according to any one of the preceding claims, wherein said compound which deactivates the oxidized product of the color developing agent is contained in the non-light-sensistive intermediate layer in an amount of 2 x 10⁻⁴ to 1 x 10⁻² mol per m².
The light-sensitive silver halide photographic material according to Claim 7, wherein said compound which deactivates the oxidized product of the color developing agent is contained in the non-light-sensistive intermediate layer in an amount of 3 x 10⁻⁴ to 5 x 10⁻³ mol per m².
The light-sensitive silver halide photographic material according to any one of the preceding claims, wherein said diffusion-resistant coupler is a yellow coupler represented by Formula (Y):
wherein R_Y1 represents a halogen atom, R_Y2 represents a hydrogen atom or a group substitutable on the benzene ring, B represents a ballast group and Z represents a hydrogen atom, a halogen atom or a group which is eliminated in the reaction with the oxidized product of the color developing agent.
The light-sensitive silver halide photographic material according to Claim 9, wherein at least one of said B and Z in Formula (Y) contains at least one functional group as follows:
-COOH, -OH, -SO₂R¹, -SOR², -COOR³, -OCOR⁴,
wherein R¹ - R⁴, R⁶, R⁷ and R¹⁰ each represent an alkyl group or an aryl group, R⁵, R⁸, R⁹ and R¹¹ each represent hydrogen atom, an alkyl group or an aryl group.
The light-sensitive silver halide photographic material according to any one of the preceding claims, wherein said diffusion-resistant coupler is a yellow coupler or a magenta coupler and the yellow coupler is contained in one of the two light-sensitive silver halide emulsion layers adjacent to said non-light-sensitive intermediate layer and the magenta coupler is contained in the other.
The light-sensitive silver halide photographic material according to any one of the preceding claims, wherein the silver halide grains in said light-sensitive silver halide photographic material contain 90 mol% or more of silver chloride.
A method of developing the light sensitive silver halide photographic material according to any one of the preceding claims wherein the colour developer is N-ethyl-N-β-methanesulphonamidoethyl-3-methyl-4-aminoaniline sulphate.