SILVER HALIDE PHOTOGRAPHIC LIGHT-SENSITIVE MATERIAL SUITABLE FOR RAPID PROCESSES

Abstract: A silver halide photographic light-sensitive material comprising a support bearing at least one silver halide emulsion layer containing a dye-forming coupler and a compound of formula [I], wherein at least one of the silver halide emulsion layers contains silver halide grains having a silver chloride content of at least 90 mol% and a compound of formula [S]; Formula [I] wherein, R₂₁, R₂₂, R₂₃ and R₂₄ are, independently, hydrogen, a halogen, alkyl, alkenyl, aryl, cycloalkyl, alkoxy, aryloxy, alkylthio, arylthio, acyl, alkylacylamino, arylacylamino, alkylcarbamoyl, arylcarbamoyl, alkylsulfonamido, arylsulfonamido, alkylsulfamoyl, arylsulfamoyl, alkylsulfonyl, arylsulfonyl, nitro, cyano, alkyloxycarbonyl, aryloxycarbonyl, alkylacyloxy or arylacyloxy, provided that at least one of R₂₁ and R₂₃ has at least three carbon atoms; Formula [S] wherein Q₁ is a group which, together with the carbon and nitrogen to which it is attached, completes a 1,3,4-oxadiazole ring, a 1,3,4-thiadiazole ring or a 1,3,5-triazine ring; and M₁ is hydrogen, an alkali metal or ammonium.

Description: This invention relates to a silver halide photographic light-sensitive material and, more particularly, to a silver halide photographic light-sensitive material which is not only endowed with a proper gradation of dye-images formed but also capable of being rapidly processed. Recently there has been considerable demand for a silver halide photographic light-sensitive material which is, in particular, rapidly processable, but also has excellent image quality and processing stability, and is inexpensive. In general, silver halide photographic light-sensitive materials are usually processed successively with automatic processors installed in every photofinisher. As service improvements, photofinishers are required to process and return their customers light-sensitive materials the same day that the order is received. Recently, photofinishers are being required to finish and return the processed materials within several hours of receipt. Thus, demands for rapid processing services are increasing. In addition innovations are demanded to rapid processing in order to shorten processing time so that production efficiency is improved and photofinishing costs are reduced. Some improvements have been made to rapid processing techniques by way of light-sensitive materials and processing liquids. For color development processes, high-temperature processes, high pH processes, and high concentrations of color developing agents have, for example, been tried and it is well-known that an additive such as a development accelerator is usefully added. Such development accelerators include, for example. 1-phenyl-3-pyrazolidone described in British Patent No. 811,185, N-methyl-p-aminophenol described in U.S. Patent No. 2,417,514, N,N,N',N'-tetramethyl-p-phenylenediamine described in Japanese Patent O.P.I. Publication No. 15554/1975. In these techniques, however, satisfactory rapid process may not occur and, in addition, there may often be instances where a deterioration in photographic characteristics occurs, such as an increase in fog. It is also known that, the configuration, size and composition of the silver halide grains in the silver halide emulsions used in light-sensitive materials greatly influence development time. In particular, the influence of silver halide grain composition is relatively greater and a remarkably high rate of development may be achieved with a silver halide containing a high concentration of chloride. With a silver halide color photographic light-sensitive material, a dye-image may be formed after the light-sensitive material is exposed to light and is then treated in a color development and so forth. However, with a silver halide color photographic light-sensitive material which uses the above-mentioned high chloride-containing silver halide suitable for rapid processing and containing couplers, the rate of production of the oxidized products of a color developing agent may in some instances become faster than the reaction rate of forming a dye upon coupling of the above-mentioned oxidized products to the couplers. If this is the case, a surplus of the oxidized products of the color developing agent causes a color turbidity because of the interlayer migration in the light-sensitive material, or causes a so-called latent-image bleach made by oxidizing a latent image nucleus formed by an exposure to light. Therefore, a compound is added which is capable of making the surplus oxidized products of the color developing agent harmless upon reacting together, in order to prevent the above-mentioned color turbidity and latent-image bleach. A large quantity of this compound is required as an alternative to not using high-chloride-containing silver halides. The most effective compounds for the purposes outlined above include, for example, hydroquinone derivatives. When a large quantity of hydroquinone derivatives are used in a light-sensitive material, a phenomenon occurs such that the contrast of the dye-image obtained has a hard toe-shape in the characteristic curve. In silver halide photographic light-sensitive materials when contrast has a too hard toe-shape it is a serious problem. It is very hard to control the gradation in the toe portion of the characteristic curve and, for example, even if the amount of silver coated is effectively adjusted so as to control the gradation in the shoulder portion of the curve, it may have very little effect on the control of the gradation of the toe portion. Also in a method of mixing monodisperse silver halide emulsions containing different sized silver halide grains together in a suitable proportion, which is often used for controlling the gradation, it is difficult to soften the toe portion. If silver halide emusions, which are to be mixed, have such a big difference in grain size from each other that the toe portion may satisfactorily be softened, the shoulder portion may be so excessively softened that such a light-sensitive material may no longer be suitable for practical use. A gradation in the toe portion of the characteristic curve will exert a serious influence upon the graphic details of a silver halide photographic light-sensitive material. If it is too hard, an image obtained will have almost no graphic detail, so that the image quality of the silver halide photographic light-sensitive material is seriously damaged. It becomes, therefore, essential to acquire a technique to soften the gradation in the toe portion. Silver halide photographic light-sensitive materials are usually processed in succession, replenishing the respective solutions, in a variety of processing laboratories such as photofinishers. It is almost impossible to keep the compositions of each processing liquid constant during a processing. Accordingly, there is a problem that photographic characteristics may vary with the changes in composition of processing liquids used. This problem is getting more serious as low-volume replenishments of processing liquids has recently become popular. In particular, it is nearly impossible to completely avoid contaminating developer with bleach-fixer, even when a strict rate of replenishing a replenisher is established, evaporation is minimised and any eluate from a light- sensitive material is eliminated. In a roller-transport or an automatic processor in particular, there may be a big difference in the amount of bleach-fixer contaminating the developer, according to the quantities of light-sensitive materials processed or the method of squeezing used. When the rate of replenishing a processing liquid is lowered, there is actually a further difference in the rate of contamination of developer by bleach fixer, because the rate of circulating the processing liquid is also lowered. Although a color developer is kept at a high pH value, it cannot be avoided that the pH values of the color developer vary according to the amounts of replenisher added, the degrees of air-oxidation of processing liquids and so forth in continuous operation. The variations in photographic characteristics including, mostly, fog increase and variations in contrasts, are caused by contamination of color developer by bleach-fixer or by varying the pH values of color developer. Such photographic characteristic variations cause difficulties in the reproduction of stable and excellent colors and contrasts. For the above-mentioned reasons and because it is very hard to avoid the contamination color developer by bleach-fixer and the prevention of pH variations, silver halide photographic light-sensitive materials have been developed which are substantially lower in photographic characteristic variations and have excellent so-called BF contamination resistance and pH variation resistance even if the developer is contaminated with bleach-fixer or the pH value is varied. We have studied the improvements of the hard toe-contrasts of a dye-image which have become a serious problem when using silver halide grains having a high silver chloride content suitable for rapid processing and a antistaining agent. We have discovered that suitable contrast characteristics can be obtained, without affecting any other photographic characteristics by using specific compounds in combination. We have also discovered that the silver halide photographic light-sensitive materials using the specific compounds are also endowed with additional advantages such as excellent BF contamination resistance and pH variation resistance. GB-A-2032923 discloses a light-sensitive silver halide photographic material comprising a support and provided thereon a silver chlorobromide emulsion layer (silver chloride content unspecified) containing 4-hydroxy-6-methyl-1,3,3a,7-tetrazaindene and a dye forming coupler dispersed using a high boiling organic solvent having a dielectric constant of 6.4. The emulsion layer may be sensitised with a gold compound. Accordingly, the invention seeks to provide a silver halide photographic light-sensitive material which is capable of rapid processing, has excellent contrast characteristics of dye-images formed thereon, BF contamination resistance and pH variation resistance. The present invention provides a silver halide photographic light-sensitive material comprising a support bearing at least one silver halide emulsion layer containing a dye-forming coupler and a compound of Formula [I], wherein at least one of the silver halide emulsion layers contains silver halide grains having a silver chloride content of not less than 90 mol% and a compound of Formula [S]. wherein R₂₁, R₂₂, R₂₃ and R₂₄ are, independently, hydrogen, halogen, alkyl, alkenyl, aryl, cycloalkyl, alkoxy, aryloxy, alkylthio, arylthio, acyl, alkylacylamino, arylacylamino, alkylcarbamoyl, arylcarbamoyl, alkylsulfonamido, arylsulfonamido, alkylsulfamoyl, arylsulfamoyl, alkylsulfonyl, arylsulfonyl, nitro, cyano, alkyloxycarbonyl, aryloxycarbonyl, alkylacyloxy or arylacyloxy, provided, however, that at least one of R₂₁ and R₂₃ has at least three carbon atoms: wherein Q₁ is a group which, together with the carbon and nitrogen atom to which it is attached, completes a 1,3,4-oxadiazole ring, a 1,3,4-thiadiazole ring or a 1,3,5-triazine ring; and M₁ is hydrogen, alkali metal or ammonium. EP-A-0255783, filed on the same day, discloses a light-sensitive silver halide photographic material comprising a support and, provided thereon, at least one light-sensitive silver halide emulsion layer characterised in that it comprises: silver halide grains containing a gold compound and having a silver chloride content of at least 90 mole %, a dye-forming coupler dispersed therein using a high boiling-point organic solvent having a dielectric constant, measured at 30°C, of not more than 6.0, and a compound of formula [S]; wherein Q is a group which, together with the carbon and nitrogen to which it is attached, completes a 5- or 6-membered heterocyclic ring or a 5- or 6-membered ring fused with a benzene ring and M is hydrogen, an alkali metal or ammonium. EP-A-0255784, filed on the same day, discloses a method of forming a dye image comprising imagewise exposing a light-sensitive silver halide photographic material which comprises a support and, provided thereon, at least one silver halide emulsion layer comprising silver halide grains containing 90 mole % or more of silver chloride, a dye-forming coupler and a compound of formula [S] defined above; the silver halide emulsion layer having been hardened by a hardener of formula [HDA] or [HDB] described below and processing the imagewise exposed photographic material with a colour developing solution which comprises from 2 x 10⁻⁴ to 1 x 10⁻² mole/liter sulfite ions and no more than 5 x 10⁻⁴ mole/liter of bromide ions. In the silver halide photographic light-sensitive materials of the invention, at least one silver halide emulsion layer thereof contains a compound represented by Formula [S]. In formula [S], the 1,3,4-oxadiazole ring, 1,3,4-thiadiazole ring and 1,3,5-triazine ring each represented by Q, include those having any substituents. Such substituent groups include, for example, alkyl, aryl, alkenyl, cycloalkyl, mercapto, amino, acylamino, sulfonamido and heterocyclic groups. The alkali metal atoms each represented by M₁ include, for example, sodium and potassium. Among compounds of Formula [S], preferable compounds include, for example, those of Formula [SA]: wherein Z is oxygen or sulfur; R A is hydrogen, alkyl, aryl, alkenyl, cycloalkyl, a -SR A1 , -NHCOR A3 , -NHSO₂R A4 or a heterocyclic group, in which R A1 and R A2 are, independently, hydrogen, alkyl or aryl and R A3 and R A4 are, independently, alkyl or aryl, and M₂ is hydrogen, alkali metal or ammonium. In Formula [SA], the alkyl groups represented by R A , R A1 , R A2 , R A3 and R A4 include, for example, methyl, ethyl or propyl, and the aryl groups include, for example, phenyl, benzyl or naphthyl. The alkenyl groups represented by R A include, for example, propenyl. An example of a cycloalkyl group is cyclohexyl. The heterocyclic groups represented include, for example, furyl and pyridinyl. The alkyl groups and aryl groups each represented by R A , R A1 , R A2 , R A3 and R A4 and the alkenyl groups, cycloalkyl groups and heterocyclic groups each represented by R A include those having a further substituent. The alkali metal atoms represented by M₂ include, for example, potassium and sodium atoms. Other preferred examples of compounds represented by Formula [S] include the compounds represented by Formula [SB]: wherein R A , R B1 and R B2 and M₃ are, independently, as defined above by R A , R A1 , R A2 and M₂ in Formula [SA], respectively. Typical examples of compounds represented by Formula [S] are given below. The compounds represented by Formula [S] include, for example, the compounds described in 'Chemical and Pharmaceutical Bulletin', Tokyo, Vol. 26, No. 314, 1978; Japanese Patent O.P.I. Publication No. 79436/1980; 'Berichte der Deutschen Chemischen Gesellsdraft', Vol. 82, No. 121, 1948; U.S. Patent Nos. 2,843,491 and 3,017,270; British Patent No. 940,169; Japanese Patent O.P.I. Publication No. 102639/1976; and 'Journal of Americal Chemical Society', No. 44, pp. 1502-1510. The syntheses thereof may be carried out in accordance with the processes described in these references. Silver halide emulsion layers relating to the invention containing compounds of Formula [S] (hereinafter called a compound [S]) can be prepared by dissolving a compound [S] in water or an organic solvent which is freely capable of being mixed with water including, for example, methanol or ethanol, and the resulting solution is added to the emulsion layer. A compound [S] may be used independently or in combination with other compounds of Formula [S] or other stabilizers and antifogging agents not within the scope of Formula [S]. The compound of formula [S] may be added at any point in time, for instance, before the formation of the silver halide grains, in the course of forming the silver halide grains, between completing the silver halide grain formation and commencing chemical ripening, during chemical ripening, at completion of chemical ripening or between completion of chemical ripening and coating. Compound [S] may be added all at once or at separate intervals. Compound [S] may be added either directly to a silver halide emulsion or a silver halide emulsion coating liquid, or to a coating liquid for coating a non-light-sensitive hydrophilic colloidal layer adjacent to the silver halide emulsion layer and therefrom to the silver halide emulsion layer through diffusion in a multicoating process. The amount of compound [S] to be added is not particularly limitative, but may ordinarily be within the range of from 1x10⁻⁶ mol to 1x10⁻¹ mol and, more preferably, from 1x10⁻⁵ mol to 1x10⁻² mol per mol of the silver halide used. Some of the compounds [S] are well-known to those skilled in the art as stabilizers or antifogging agents. They are described in, for example, British Patent No. 1,273,030, Japanese Patent Examined Publication Nos. 9936/1983 and 27010/1985, and Japanese Patent O.P.I. Publication Nos. 102639/1976, 22416/1978, 59463/1980, 79436/1980 and 232342/1984. Descriptions of fog inhibiting and emulsion stabilizing techniques are provided in the above-mentioned literature. However, it has hitherto not been possible to improve image contrast liable to be hardened so as to maintain sufficient contrast and such hardened image contrast may be achieved when color developing a silver halide photographic light-sensitive material containing dye-forming couplers, silver halide grains having a high silver chloride content and an antistaining agent, according to the invention. Compounds of formula [S] have generally been known as compounds capable of displaying an antifogging effect together with desensitizing and development inhibiting effects. (This is described in, for example, Society of Photographic Science and Technology of Japan, 'Basic Photographic Engineering - Silver Halide Photographic Edition', Corona Publishing Co., 1979, p. 195. There is no document in the prior art which suggests that dye-images liable to be hardened can be improved without adversely affecting any rapid processability and processing stability by applying the above-mentioned compounds to the present silver halide light-sensitive materials. The present silver halide light-sensitive materials also display other effects which are quite beyond expectation. Namely, the so-called BF contamination resistance and pH variation resistance are so improved that a very stable and excellent reproducibility can be displayed against both the contamination of bleach-fixer into the color developer and the variations of photographic characteristics caused by the pH variations of the color developer, including, for example, contrast variation. More precisely, the compounds represented by Formula [SA] display a relatively greater effect on BF contamination resistance and the compounds represented by Formula [SB] display a relatively greater effect on pH variation resistance. Of compounds of Formula [SA], compounds in which Z represents oxygen may be able to display more preferable effects than those in which Z represents sulfur. The silver halide emulsion layers having a compound [S] contain silver halide grains having a silver chloride content of not less than 90 mol%. The silver halide grains used in the invention, have a silver chloride content of not less than 90 mol%, and preferably have a silver bromide content of not more than 10 mol% and a silver iodide content of not more than 0.5 mol% and, more preferably, the silver halide grains contain silver chlorobromide having a silver bromide content of from 0.05 to 5 mol%, respectively. The silver halide grains used in the invention may be used either independently or in combination with the other silver halide grains having a different composition. Silver halide grains as described above may be mixed together with silver halide grains having a silver chloride content of less than 10 mol%. In the silver halide emulsion layers each containing silver halide grains having a silver chloride content of not less than 90 mol%, the proportion of silver halide grains having a silver chloride content of not less than 90 mol% to the total silver halide grains contained in each of the above-mentioned emulsion layers is typically not less than 60% by weight and, more preferably, not less than 80% by weight. The composition of the silver halide grains may be either uniform throughout or the composition of the inside of the grain may differ from that of the outside. When the composition of the grain differs between the inside and the outside of the grains, the composition may be varied either continuously or intermittently. There is no special limitation to the grain sizes of the silver halide grains used in the invention. However, taking the other photographic characteristics such as, for example, rapid processability and sensitivity into consideration, the grain sizes are preferably to be within the range of from 0.2 to 1.6 µm and, more preferably, from 0.25 to 1.2 µm. The above-mentioned grain sizes may be measured by a variety of conventional methods. Typical methods include those described in, for example, R.P. Loveland, 'Particle-Size Measurement', ASTM Symp. on Light Microscopy, 1955, pp. 94-122; or C.E.K. Mees and T.H. James. 'The Theory of the Photographic Process', 3rd Ed., The Macmillan Co., 1966, Chap. 2. The above-mentioned grain sizes may be measured in terms of a projective area of a grain or an approximate diameter thereof. When every grain has a substantially uniform configuration, the accurate grain size distribution thereof may be expressed in terms of a diameter or projective area of the grains. The grain size distribution of the silver halide grains used in the invention may be either polydisperse or monodisperse. Preferably the silver halide grains are monodisperse, having a variation coefficient of the grain size distribution of not more than 0.22 and, more preferably, of not more than 0.15. The above-mentioned variation coefficient means a coefficient expressing a spreading area of grain size distribution which can be defined by the following equations: wherein ri represents the grain sizes of individual grains and ni represents the number of the individual grains. The term grain size mentioned herein means the diameter of a grain in the case of globular-shaped silver halide grains, and the diameter of a circular image obtained by converting the projected image of the grain into a circular image having the same area as the area of the projected image in the case of a cubic or other shaped grain. The silver halide grains may typically be prepared in an acid process, a neutral process or an ammonia process. The grains may be grown either directly or after preparing seed grains. The respective processes of preparing and growing such seed grains may be the same as or different from each other. The processes of reacting a soluble silver salt with a soluble halide may be freely selected from normal, reverse and double-jet precipitation processes and combinations thereof. The double-jet precipitation process is preferred. A version of the double-jet precipitation process such as the pAg-controlled double-jet process described in, for example, Japanese Patent O.P.I. Publication No. 48521/1979 may be additionally applied. A silver halide solvent such as thioether may also be used, if required. Any configurations of the silver halide grains may be used. A preferable example of a configuration is cubic having a (100) plane as the crystal face thereof. Grains each having, for example, an octahedral, tetradecahedral, dodecahedral configuration may be used, for example, as prepared in the processes as described in, U.S. Patent Nos. 4,183,756 and 4,225,666; Japanese Patent O.P.I. Publication No. 26589/1980; Japanese Patent Examined Publication No. 42737/1980 and 'The Journal of Photographic Science', 21 , 39, 1973. Further, a grain having a twin-crystal face may be used. Silver halide grains having a uniform configuration or mixed with grains having a variety of configurations may be used. During the formation or growth of the silver halide grains, the grains can contain metal ions (either inside the grains or on the surfaces thereof) such as a cadmium salt, a zinc salt, a thalium salt, an iridium salt or complexes thereof, a rhodium salt or complexes thereof or an iron salt or complexes thereof. Also, a reduction-sensitization speck may be provided inside and/or on the surface of the grains by placing the grains in a suitable reduction atmosphere. Unnecessary soluble salts may be removed from emulsions containing silver halide grains used in the invention (hereinafter called emulsions used in the invention) after completing the growth of the silver halide grains or the emulsion may be left as they are. Removal of such unnecessary salts may be carried out in accordance with the method described in, for example, 'Research Disclosure', No. 17643. Silver halide grains which are to be used in emulsions used in the invention may be of the type which forms a latent image mainly either on the insides or the surfaces of the grains. The preferable grains are of the latter type. The emulsions used in the invention may be chemically sensitized in an ordinary process. Namely, sensitization processes may be used independently or in combination, including, for example, a sulfur sensitization process in which a compound or an active gelatin contains sulfur and is capable of reacting with silver ions; a selenium sensitization process in which a selenium compound is used; a reduction sensitization process in which a reducible substance is used; or a noble metal sensitization process in which a gold or another noble metal compound is used. Chemical sensitizers such as a chalcogen sensitizer may be used. 'Chalcogen sensitizer' is a general term for sulfur sensitizers, selenium sensitizers and tellurium sensitizers. Sulfur or selenium sensitizers are preferable for photographic use. Suitable sulfur sensitizers include, for example, thiosulfates, allylthiocarbazides, thio ureas, allylisothiocyanates, cystines, p-toluenethiosulfonates and rhodanines. Sulfur sensitizer such as those described in, for example. U.S. Patent Nos. 1,574,944, 2,410,689, 2,278,947, 2,728,668, 3,501,313 and 3,656,955;West German Patent (OLS) Publication No. 1,422,869 or Japanese Patent O.P.I. Publication Nos. 24937/1981 and 45016/1980 may alternatively be used. The amount of sulfur sensitizer to be added varies extensively over a considerablly wide range, depending upon the various conditions such as the size of the silver halide grains. The amount added is preferably from 10⁻⁷ mol to 10⁻¹ mol per mol of the silver halide used. A selenium sensitizer may also be used instead of the above-mentioned sulfur sensitizers. Selenium sensitizers include, for example, aliphatic isoselenocyanates such as an allylisoselenocyanate; selenoureas; selenoketones; selenamides; selenocarboxylates and esters thereof; selenophosphates; and selenides such as a diethyl selenide or a diethyl diselenide. Typical examples are given in U.S. Patent Nos. 1,574,944, 1,602,592 and 1,623,499. Further, a reduction sensitizer may be used. There is no special limitation thereto, however, such reducing agents include, for example, a stannous chloride, a thiourea dioxide, a hydrazine and a polyamine. Noble metal compounds other than gold compounds, such as palladium compounds, may also be used in combination. The silver halide grains used in the invention preferably contain a gold compound. The gold compounds are preferably those having a gold oxidation number of either one or three, and a variety of gold compounds may be used. Typical examples of a suitable gold compound include a potassium chloroaurate, an auric trichloride, a potassium auric thiocyanate, a potassium iodoaurate, a tetracyanauric azide, an ammonium aurocyanate, a pyridyltrichlorogold, a gold sulfid and a gold selenide. The gold compounds may be used either to sensitize the silver halide grains or so as not to contribute substantially to any sensitization. The amount of gold compound to be added depends upon a variety of conditions applied, but typically is from 10⁻⁸ mol to 10⁻¹ mol and, preferably, from 10⁻⁷ mol to 10⁻² mol per mol of the silver halide used. The above-mentioned compounds may be added at any time during formation of the silver halide grains, physical ripening, chemical ripening or after completion of chemical ripening. The emulsions used in the invention may be spectrally sensitized to any desired wavelength region by a spectral sensitizer which is well-known in the photographic industry. The spectral sensitizers may be used independently or in combination. The emulsions used in the invention may also contain not only the above-mentioned spectral sensitizers but also a dye not having any spectral sensitizing function or a super-sensitizer which is a compound substantially incapable of absorbing any visible rays of light but is capable of reinforcing the sensitizing function of the spectral sensitizer used. The silver halide emulsion layers used in the invention contain compounds of Formula [I]: In the compounds represented by the above-given Formula, R₂₁, R₂₂, R₂₃ and R₂₄ are, independently, hydrogen, halogen, alkyl, alkenyl, aryl, cycloalkyl, alkoxy, aryloxy, alkylthio, arylthio, acyl, alkylacylamino, arylacylamino, alkylcarbamoyl, alkylsulfonamido, arylsulfonamido, alkylsulfamoyl, arylsulfamoyl, alkylsulfonyl, arylsulfonyl, nitro, cyano, alkyloxycarbonyl, aryloxycarbonyl, alkylacyloxy or arylacyloxy. Of the atoms or groups represented by R₂₁, R₂₂, R₂₃ and R₂₄, halogen includes, for example, fluorine, chlorine and bromine; and alkyl includes, for example, methyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl, n-amyl, i-amyl, n-octyl, n-dodecyl and n-octadecyl, and particularly preferable alkyl groups are those each having 1 to 32 carbon atoms. The alkenyl groups include, for example, allyl, octenyl and oleyl, and particularly preferable alkenyl groups are those each having 2 to 32 carbon atoms. The aryl groups include, for example, phenyl and naphthyl. The acyl groups include, for example, acetyl octanoyl and lauroyl. The cycloalkyl groups include, for example, cyclohexyl and cyclopentyl. The alkoxy groups include, for example, methoxy, ethoxy and dodecyloxy; the aryloxy groups include, for example, phenoxy; the alkylthio groups include, for example, methylthio, n-butylthio and n-dodecylthio groups; the arylthio groups include, for example, phenylthio; the alkylacylamino groups include, for example, acetylamino; the arylacylamino groups include, for example, benzoylamino; the alkylcarbamoyl groups include, for example, methylcarbamoyl; the arylcarbamoyl groups include, for example, phenylcarbamoyl; the alkylsulfonamido groups include, for example, methylsulfonamido; the arylsulfonamido groups include, for example, phenylsulfonamido; the alkylsulfamoyl groups include, for example, methylsulfamoyl; the arylsulfamoyl groups include, for example, phenylsulfamoyl; the alkylsulfonyl groups include, for example, methylsulfonyl; the arylsulfonyl groups include, for example, phenylsulfonyl; the alkyloxycarbonyl groups include, for example, methyloxycarbonyl; the aryloxycarbonyl groups include, for example, phenyloxycarbonyl; the alkylacyloxy groups include, for example, acetyloxy; and the arylacyloxy groups include, for example, benzoyloxy. The above-mentioned groups include those each having a substituent. Such substituents include, for example, alkyl, aryl, aryloxy, alkylthio, cyano, acyloxy, alkoxycarbonyl, acyl, sulfamoyl, hydroxy, nitro, amino and heterocyclic groups. At least one group out of the groups represented by R₂₁ and R₂₃ is to have not less than 3 carbon atoms in total including the carbon atoms of the substituent thereof given above. Of the compounds of Formula [I], compounds of Formulas [II] and [III] may preferably be used in the invention. wherein R₁ and R₂ are, independently, alkyl such as butyl, pentyl or octyl, aryl such as phenyl, alkenyl such as propenyl butenyl, cycloalkyl such as cyclohexyl, or a heterocyclic group such as cumarone. The above-mentioned groups include those each having a substituent. Such substituents include, for example, alkyl or aryl groups. wherein R₃ and R₄ are, independently alkyl having 1 to 5 carbon atoms, such as methyl, propyl or pentyl; R₅ is alkyl such as methyl, pentyl or dodecyl, aryl such as phenyl, alkenyl such as propenyl or butenyl, cycloalkyl such as cyclohexyl, a heterocyclic group such as cumarone, or wherein n is an integer of from 1 to 20; k is 1 or 2:and Q₂ and Q₃ are, independently, -COXR₆ in which X is oxygen or R₆ represents hydrogen, alkyl such as methyl, hexyl or dodecyl, alkenyl such as propenyl, cycloalkyl such as cyclohexyl or aryl such as phenyl; R₇ represents hydrogen, alkyl such as methyl, or aryl such as phenyl; and each of the above-mentioned groups include those having a substituent; -OY in which Y is, independently, as defined for -R₆ or -COR₆; in which R₇ is as defined above and R₈ is hydrogen, alkyl, aryl or -COR₆; -P(O)(OR₆)([O] ℓ R₉) in which R₉ is, independently, as defined for R₆ and ℓ is 0 or 1, or a cyano group. Typical examples of compounds represented by Formula [I] are given below: The hydroquinone derivatives of Formula [I] may be efficiently added in any amount within the range of from 1x10⁻³ mol to 1 mol per mol of the couplers used and, more preferably, in an amount within the range of from 5x10⁻³ mol to 0.5 mol. The hydroquinone derivatives are generally added into a silver halide emulsion layer containing couplers. However, they may also be added into the layers adjacent to the emulsion layer without difficulty. The above-mentioned hydroquinone derivatives have so far been known as antistaining agents and are described in, for example, Research Disclosure, No. 176, 1978, Article 17643, VII-I and Japanese Patent O.P.I. Publication Nos. 24141/1983, 180557/1984, 189342/1984 and EP-A- 0122125. A dye-forming coupler may be applied to the silver halide emulsion layers of the silver halide photographic light-sensitive materials of the invention. It is preferred that such dye-forming couplers contain a group having not less than 8 carbon atoms capable so that it is a ballast group which is not dispersive. Acylacetanilide type couplers may preferably be used as yellow dye-forming couplers. Of these couplers, benzoylacetanilide or pivaloylacetanilide type compounds are preferable. The preferable compounds are represented by the following Formula [Y]: wherein R 1Y is halogen or alkoxy; R 2Y is hydrogen, halogen or alkoxy; R 3Y is acylamino, alkoxycarbonyl, alkylsulfamoyl, arylsulfamoyl, arylsulfonamido, alkylureido, arylureido, succinimido, alkoxy or aryloxy; and Z 1Y is a group capable of splitting off in a coupling reaction with an oxidized product of a color developing agent. Typical examples of yellow couplers which may be used are those described in British Patent No. 1,077,874; Japanese Patent Examined Publication No. 40757/1970; Japanese Patent O.P.I. Publication Nos. 1031/1972, 26133/1972, 94432/1973, 87650/1975, 3631/1976, 115219/1977, 99433/1979, 133329/1979 and 30127/1981; and U.S. Patent Nos. 2,875,057, 3,253,924, 3,265,506, 3,408,194, 3,551,155, 3,551,156, 3,664,841, 3,725,072, 3,730,722, 3,891,445, 3,900,483, 3,929,484, 3,933,500, 3,973,968, 3,990,896, 4,012,259, 4,022,620, 4,029,508, 4,057,432, 4,106,942, 4,133,958, 4,269,936, 4,286,053, 4,304,845, 4,314,023, 4,336,327, 4,356,258, 4,386,155 and 4,401,752. 5-Pyrazolone type couplers and pyrazoloazole type couplers may preferably be used as magenta dye-forming couplers. More preferable couplers are represented by the following formula [P] or [a]: wherein Ar is aryl; R p1 is hydrogen or a substituent; R p2 is a substituent; Y is hydrogen or a group capable of splitting off in a reaction with the oxidized product of a color developing agent; W is -NH-, -NHCO- in which the N atom is able to couple to a carbon atom of a pyrazolone nucleus, or -NHCONH-; and m is 1 or 2. wherein Za is a group which, together with the carbon and nitrogen atoms to which it is attached, completes a nitrogen-containing heterocyclic ring, which may have a substituent; X is hydrogen or a group capable of splitting off in a reaction with the oxidized product of a color developing agent; and Ra is hydrogen or a substituent. The substituents represented by Ra include, for example, halogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, aryl, a heterocyclic group, acyl, sulfonyl, sulfinyl, sulfonyl, carbamoyl, sulfamoyl, cyano, a spiro-compound residue, an organic hydrocarbon compound residue, alkoxy, aryloxy, a heterocyclicoxy, siloxy, acyloxy, carbamoyloxy, amino, acylamino, sulfonamido, imido, ureido, sulfamoylamino, alkoxycarbonylamino, aryloxycarbonylamino, alkoxycarbonyl, aryloxycarbonyl, alkylthio, arylthio or heterocyclic thio. The above-mentioned couplers are described in, for example, U.S. Patent Nos. 2,600,788, 3,061,432, 3,062,653, 3,127,269, 3,311,476, 3,152,896, 3,419,391, 3,519,429, 3,555,318, 3,684,514, 3,888,680, 3,907,571, 3,928,044, 3,930,861, 3,930,866 and 3,933,500; Japanese Patent O.P.I. Publication Nos. 29639/1974, 111631/1974, 129538/1974, 13041/1975, 58922/1977, 62454/1980, 118034/1980, 38043/1981, 35858/1982 and 23855/1985; British Patent No. 1,247,493; Belgian Patent Nos. 769,116 and 792,525; West German Patent No. 2,156,111; Japanese Patent Examined Publication No. 60479/1971; Japanese Patent O.P.I. Publication Nos. 125732/1984, 228252/1984, 162548/1984, 171956/1984, 33552/1985 and 43659/1985; West German Patent No. 1,070,030; and U.S. Patent No. 3,725,067. Phenol type or naphthol type cyan dye-forming couplers may be used as cyan dye-forming couplers. Of these couplers, the couplers of formula [E] or [F] may preferably be used. wherein R 1E is aryl, a cycloalkyl or a heterocyclic group; R 2E is alkyl or phenyl; R 3E is hydrogen, halogen, alkyl or alkoxy; and Z 1E is hydrogen or a group capable of splitting off in a reaction with the oxidized product of an aromatic primary amine type color developing agent. wherein R 4F is alkyl such as methyl, ethyl, propyl, butyl or nonyl; R 5F is alkyl such as methyl or ethyl; R 6F is hydrogen, halogen such as fluorine, chlorine or bromine, or alkyl such as methyl or ethyl and R₂F is hydrogen or a group capable of splitting off in a reaction with the oxidized product of an aromatic primary amine type color developing agent. The above-mentioned cyan dye-forming couplers are described in, for example, U.S. Patent Nos. 2,306,410, 2,356,475, 2,362,598, 2,367,531, 2,369,929, 2,423,730, 2,474,293, 2,476,008, 2,498,466, 2,545,687, 2,728,660, 2,772,162, 2,895,826, 2,976,146, 3,002,836, 3,419,390, 3,446,622, 3,476,563, 3,737,316, 3,758,308 and 3,839,044; British Patent Nos. 478,991, 945,542, 1,084,480, 1,377,233, 1,388,024 and 1,543,040; and Japanese Patent O.P.I. Publication Nos. 37425/1972, 10135/1975, 25228/1975, 112038/1975, 117422/1975, 130441/1975, 6551/1976, 37647/1976, 52828/1976, 108841/1976, 109630/1978, 48237/1979, 66129/1979, 131931/1979, 32071/1980, 146050/1984, 31953/1984 and 117249/1985. The dye-forming couplers may generally be used in an amount within the range of from 1x10⁻³ mol to 1 mol and, more preferably, from 1x10⁻² mol to 8x10⁻¹ mol per mol of the silver halide used. The above-mentioned dye-forming couplers may be added to a hydrophilic colloidal layer by dissolving them in a high boiling organic solvent having a boiling point of about not lower than 150°C and, if required, in combination with a low boiling and/or water-soluble organic solvent and the resulting solution is dispersed in a hydrophilic binder such as an aqueous gelatin solution so as to be emulsified using a surface active agent and the resulting emulsion may be added to the objective hydrophilic colloidal layer. The low boiling organic solvent may be removed after or during the dispersion step. The high boiling organic solvents which may be used in the invention include, for example, esters such as a phthalate or a phosphate, organic acid amides, ketone and hydrocarbon compounds. The silver halide photographic light-sensitive materials of the invention may be used as, for example color negative film, color positive film or color print paper. The effects of the invention can be more easily appreciated when the material is used as a color print paper for a photograph. The silver halide photographic light-sensitive materials typically including the above-mentioned color print papers may be either monochromic or multicolor. For the purpose of performing a subtractive color reproduction, multicolor silver halide photographic light-sensitive materials usually have a structure such that the support thereof is laminated thereon in a suitable layer arrangement with both non-light-sensitive layers and silver halide emulsion layers respectively containing magenta, yellow and cyan couplers as photographic couplers. Layer numbers and arrangements may be changed to meet the purposes of the light-sensitive materials. The particularly preferable layer arrangement of a multicolor silver halide photographic light-sensitive material is that a yellow-dye-image forming layer, an interlayer, a magenta-dye-forming layer, an interlayer, a cyan-dye-image forming layer, an interlayer and a protective layer are arranged respectively over to and in order from the support of the light-sensitive material. Gelatins may advantageously be used as binders or protective colloids for use in the silver halide light-sensitive materials of the invention. Gelatin derivatives, graft polymers of gelatins and other macromolecular substances, proteins, sugar derivatives, cellulose derivatives, and hydrophilic colloids including, for example, a monomeric or polymeric synthetic hydrophilic macromolecular substance may also be used in addition to, or instead of, gelatins. The photographic emulsion layers and other hydrophilic colloidal layers of the silver halide photographic light-sensitive materials of the invention may be hardened by making use, independently or in combination, of a hardening agent which cross-links binders or protective colloids to each other and reinforces the layer strength. A hardening agent is desirably added so as not to add any excess hardening agent into a processing liquid but to satisfactrily harden the layers. It is, however, possible to add a hardening agent into processing liquids. For satisfactorily hardening a silver halide emulsion layer in the invention, it is preferable to use the chlorotriazine type hardening agents of formula [HDA] or [HDB]: wherein R d1 is chlorine, hydroxy, alkyl, alkoxy, alkylthio, -OM₄ in which M₄ is a monovalent metal, -NR'R'' in which R' and R'', independently, represent hydrogen, alkyl or aryl, or -NHCOR''' in which R''' is hydrogen, alkyl or aryl; and R d2 is, independently, a group as defined for R d1 , with the exception of chlorine. wherein R d3 and R d4 are, independently, chlorine, hydroxy, alkyl, alkoxy or -OM₅ in which M₅ is a monovalent metal; Q₄ and Q₄' are, independently a bonding group indicating -O-, -S- or -NH-; L is alkylene or arylene; an ℓ and m are, independently, 0 or 1. Typical examples of preferable hardening agents represented by formulae [HDA] and [HDB] are shown below: Compound No. R d1 R d2 HD-1 -OH -ONa HD-2 -Cl -ONa HD-3 -OCH₃ -ONa HD-4 -Cl -OC₂H₅ HD-5 -Cl -OK HD-6 -OH -OK HD-7 -Cl -NH₂ HD-8 -Cl -NHCOCH3 HD-9 -OH -NHC₂H₅ The hardening agents represented by the formula [HDA] or [HDB] may be added into silver halide emulsion layers and other component layers in such a manner that the hardening agent is dissolved in water or a water-miscible solvent such as methanol or ethanol and the resulting solution is added into the coating liquids of the above-mentioned component layers. Either a batch adding method or an in-line adding method are suitable examples of methods of adding such hardening agents. There is no special limitation in the time at which hardening agents may be added but it is, however, preferable to add them immediately before coating. These hardening agents are typically added in an amount of from 0.5 to 100 mg and, more preferably, from 2.0 to 50 mg per g of gelatin to be coated. A plasticizer may also be added to the silver halide photographic light-sensitive materials of the invention in order to increase the softness of the silver halide emulsion layers and/or other hydrophilic colloidal layers. In the silver halide photographic light-sensitive materials of the invention, the photographic emulsion layers and other hydrophilic colloidal layers thereof may contain a water-insoluble or sparingly soluble synthetic polymer dispersion, i.e., a latex, in order to improve, for example, the dimensional stability. An image stabilizer may be used in the silver halide photographic light-sensitive materials of the invention in order to prevent a dye image from deteriorating. The hydrophilic colloidal layers, such as the protective layers and interlayers, may contain a UV absorbing agent, in order to prevent fog being produced, for example, by a discharge of frictional charge and also preventing image deterioration caused by UV rays. The silver halide photographic light-sensitive materials of the invention may be provided with auxiliary layers such as a filter layer, an antihalation layer or an antiirradiation layer. These layers and/or emulsion layers can also contain a dye such as is extravasated from a color light-sensitive material or is bleached, in the course of a development process. The silver halide emulsion layers and/or other hydrophilic colloidal layers may contain a matting agent, in order to reduce the gloss of the light-sensitive material, increase the retouchability, prevent adhesion to another light-sensitive material. A lubricating agent may be added to the silver halide photographic light-sensitive materials of the invention in order to reduce sliding friction. An antistatic agent may be added to the silver halide photographic light-sensitive materials of the invention in order to prevent static. There are some cases where such an antistatic agent is used in an antistatic layer provided to the side of a support where no emulsion is coated, or other cases where such an antistatic agent is used in a protective layer other than the emulsion layers provided to the side of the emulsion layers and/or to the side of the support where the emulsion layers are coated. The photographic emulsion layers and/or other hydrophilic colloidal layers thereof may contain a variety of surface active agents, in order to improve coatability, prevent static, improve slidability, improve emulsification and dispersion, prevents adhesion, and improve photographic characteristics such as development acceleration, hardening and sensitization. The photographic emulsion layers and other layers thereof may be coated over flexible reflection type supports such as a baryta paper, an α-olefin-polymer-laminated paper, a synthetic paper; film supports comprising such a semisynthetic or synthetic polymer as a cellulose acetate, a cellulose nitrate, a polystyrene, a polyvinyl chloride, a polyethylene terephthalate, a polycarbonate or a polyamide; or solid supports such as a glass, metal or earthware. The surfaces of the support may be treated, if required, by, for example, a corona discharge, UV rays irradiation or flame and may then be coated directly or through one or two subbing layers which are present to improve the adhesive property, antistatic property, dimensional stability, antiabrasive property, hardness, antihalation property, frictional property and/or other properties of the surfaces of the support. When silver halide emulsions are coated onto the silver halide photographic light-sensitive materials of the invention, a thickening agent may be used in order to improve the coatability. It is particularly advantageous to apply an extrusion coating process or a curtain coating process as the coating process, because these processes are capable of applying emulsions to not less than two layers at the same time. The light-sensitive materials of the invention can be exposed to light using electromagnetic waves in the same spectral regions to which the emulsion layers forming the light-sensitive material of the invention are sensitive. As for the light sources, any one of the well-known light-sources may be used, such as natural light, i.e., daylight, a tungsten lamp, a fluorescent lamp, a mercury lamp, a xenon-arc lamp, a carbon-arc lamp, a xenon flash lamp, a CRT flying spot, a variety of laser beams, an LED or a light emitted from a phosphor excited by an electron, X-ray, γ-ray or α-ray beam. An exposure may be made not only for one millisecond or less, for example from 100 microseconds to one millisecond using a CRT or xenon flash lamp, but also for 10 seconds or longer, as well as from one millisecond to 10 seconds using an ordinary type printer. Such an exposure may be made continuously or intermittently. An image can be reproduced from the silver halide photographic light-sensitive materials of the invention, using any conventional color developing process. The color developing agents which may be used in the color developer include well-known agents which are widely used in a variety of color photographic processes. These developing agents include, for example, aminophenol type and p-phenylenediamine type derivatives. These are generally used in the form of a salt such as a chloride or sulfate because these compounds are more stable in salt form compared to their free state. These compounds are generally used in a concentration of from 0.1 g to 30 g and, more preferably, from 1 g to 15 g per liter of the color developer to be used. The aminophenol type developing agents include, for example, o-aminophenol, p-aminophenol, 5-amino-2-oxytoluene, 2-amino-3-oxytoluene and 2-oxy-3-amino-1,4-dimethylbenzene. The particularly useful aromatic primary amine type color developing agents include, for example, an N,N'-dialkyl-p- phenylenediamine type compound in which the alkyl and phenyl groups may be substituted with any substituent, respectively. The more useful compounds among them include, for example, N,N'-diethyl-p-phenylenediamine hydrochloride, N-methyl-p-phenylenediamine hydrochloride, N,N'-dimethyl-p-phenylenediamine hydrochloride, 2-amino-5-(N-ethyl-N-dodecylamino)toluene, N-ethyl-N-β-methanesulfonamidethyl-3-methyl-4-aminoaniline sulfate, N-ethyl-N-β-hydroxyethylaminoaniline, 4-amino-3-methyl-N,N'-diethylaniline, and 4-amino-N-(2-methoxyethyl)-N-ethyl-3-methylaniline-p-toluene sulfonate. Suitable color developers may contain, besides the above-mentioned aromatic primary amine type color developing agents, any compounds which are well known as component compounds of developers. For example, alkalis such as sodium hydroxide, sodium carbonate and potassium carbonate, alkali-metal sulfites, alkali-metal hydrogensulfites, alkali-metal thiocyanates, alkali-metal halides, benzyl alcohols, water-softening agents, or thickening agent may be added. The pH value of color developers is, normally, not lower than 7 and, preferably, from about 10 to about 13. The color developing temperature is, normally, not lower than 15°C and, preferably, from 20°C to 50°C. It is preferable to carry out rapid development at a temperature of not lower than 30°C. It is also preferable for the normal color developing time to be from 20 seconds to 60 seconds and, more preferably, from 30 seconds to 50 seconds. The silver halide photographic light-sensitive materials relating to the invention may be processed in an alkaline-activated bath, provided that the hydrophilic colloidal layers thereof contain the above-mentioned color developing agent to serve as such or as a precursor. Color developing agent precursors are compounds capable of producing a color developing agent under alkaline conditions and such precursors include, for example, a Schiff base type precursor with an aromatic aldehyde derivative, a polyvalent metal ion complex precursor, a phthalimide derivative precursor, a phosphamide derivative precursor, a sugar amine reactant precursor and a urethane type precursor. The above-mentioned precursors of aromatic primary amine type color developing agents are described in, for example, U.S. Patent Nos. 3,342,599, 2,507,114, 2,695,234 and 3,719,492; British Patent No. 803,783; Japanese Patent O.P.I. Publication Nos. 185628/1978 and 79035/1979; and Research Disclosure Nos. 15159, 12146 and 13924. The aromatic primary amine type color developing agents or the precursors thereof are added in an amount capable of satisfactorily developing a color upon activation. The amount to be added depends considerably upon the kinds of the light-sensitive materials used, and they are generally used in an amount from 0.1 mol to 5 mol and, more preferably, from 0.5 mol to 3 mol, per mol of the silver halide to be used therein. The above-mentioned color developing agents and precursors thereof may be used independently or in combinations thereof. They may be contained in the light-sensitive material after being dissolved in a suitable solvent such as water, methanol or acetone, or they may be added in the form of an emulsified dispersion prepared by dissolving them in a high boiling organic solvent such as dibutyl phthalate, dioctyl phthalate or tricresyl phthalate. Further, they may be added after being impregnated into a latex polymer, as described in Research Disclosure No. 14850. The silver halide photographic light-sensitive material is color-developed and is then bleached and fixed. The bleaching step may be carried out at the same time as the fixing step. A variety of compounds may be used as bleaching agents. Examples are polyvalent metal compounds such as iron (III), cobalt (III) or copper (II) and, particularly, complex salts of the polyvalent metal cation of the above-mentioned polyvalent metal compounds and an organic acid, including, for example, aminopolycarboxylic acids such as ethylenediamine tetraacetic acid, nitrilotriacetic acid, and N-hydroxyethylethylenediamine diacetic acid;, metal complex salts such as ferricyanates and dichromates, for example, of malonic acid, tartaric acid, malic acid, diglycolic acid or dithioglycolic acid. These may be used singly or in a suitable combination. Suitable fixing agents may be prepared using a soluble complexing agent capable of forming a complex salt with a soluble silver halide. Soluble complexing agents include, for example, sodium thiosulfate, ammonium thiosulfate, potassium thiocyanate, thiourea and thioether. Washing is normally carried out after fixing. A stabilizing step may be carried out instead of, a washing step, or both steps may be carried out. Stabilizing agents, which may be used in the stabilizing step, may contain, for example, a pH adjusting agent, a chelating agent and an antimold. Typical conditions may be referred to in, for example, Japanese Patent O.P.I. Publication No. 134636/1983. The silver halide photographic light-sensitive materials of the invention having the constitution described above are capable of rapid processing, displaying proper contrast characteristics without affecting any other photographic characteristics of the dye-image formed and are further endowed with an improved BF contamination resistance and pH variation resistance. Examples The following Examples illustrate the invention. Example-1 Preparation of silver halide emulsions EM-1 This emulsion was prepared by mixing silver nitrate solution and sodium chloride solution in an aqueous inert gelatin solution in a double-jet process while stirring and controlling temperature, pH and pAg at 60°C, pH=3.0 and pAg=7.8, respectively, and then desalting and washing in conventional processes. The resulting emulsion EM-1 was a monodisperse type emulsion which comprised cubic silver chloride grains having an average grain size of 0.5 µm. EM-2 An emulsion EM-2 was prepared by mixing on aqueous halide solution which comprised silver nitrate solution and potassium bromide and sodium chloride solution in an aqueous inert gelatin solution in a double-jet process while stirring and controlling temperature, pH and pAG at 60°C, pH=3.0 and pAg=7.8, in accordance with the process described in Japanese Patent O.P.I. Publication No. 45437/1984, respectively, and then desalting and washing in conventional processes. The emulsion EM-2 was a monodisperse type emulsion which comprised cubic silver bromochloride grains having an average grain size of 0.5 µm and a silver bromide content of 0.15 mol% in the silver halide composition. EM-3 An emulsion EM-3 was prepared in the same manner as EM-2 and the resulting EM-3 was a monodisperse type emulsion which comprised tetradecahedral silver chlorobromide grains having an average grain size of 0.5 µm and a silver bromide content of 90 mol% in the silver halide composition. Next, each of the emulsions, EM-1 to EM-3, was chemically sensitized by applying a sulfur sensitiza- tion by way of adding sodium thiosulfate in an amount of 2 mg per mol of the silver halide emulsions at 60°C and a compound represented by the formula [S] given in Table-1 was then added when the sulfur sensitization was completed. Thus, the emulsions shown in Table-1, Em-a to Em-m and Em-1 to Em-15 were prepared from Em-1 to Em-3. The chemically sensitized silver halide emulsions were added to the coupler dispersions shown in Table-1, respectively. The emulsions were coated over to polyethylene resin-coated paper so that the amount of silver coated was 0.3 g/m² (0.4 g/m² when MC-1 was used) in terms of metal silver contents and the gelatin coated was 2.0 g/m². The following compound [H-1] was used as a hardening agent. Coupler dispersions Each of the coupler dispersions was prepared in such a manner that 40 g of the coupler and the hydroquinone derivative shown in Table-1 were dissolved in a solvent mixture of 10 ml of dibutyl phthalate and ethyl acetate and the resulting solution was added into an aqueous solution containing sodium dodecylbenzenesulfonate and a dispersion was made using a super-sonic homogenizer. The formulae of couplers (YC-1), (MC-1) and (CC-1) and the comparative compounds to Compound [S] used are shown below: Comparative Compound-1 Comparative Compound-2 Each of the samples prepared was exposed to light through a wedge using a sensitometer, Model KS-7 manufactured by Konishiroku Photo Industry Co., Ltd., and were then processed in accordance with the color developing steps shown below. The sensitometry of each sample was measured with an optical densitometer, Model PDA-65 manufactured by Konishiroku Photo Industry Co., Ltd. The results are shown in Table-1. In the table, γa means a value of the product of each difference between the logarithms of the exposures necessary for obtaining the densities 0.25 and 0.75 and the difference between the above-mentioned densities 0.25 and 0.75, i.e., 0.5. This value expresses toe-contrast and a higher value indicates a higher contrast. Developing time is expressed as the time necessary for completing development, i.e., the time at which the development of each sample reaches a plateau. [Processing steps] Temperature Time Color developing 34.7 ± 0.3°C See Table-1 Bleach-fixing 34.7 ± 0.5°C 50 Sec. Stabilizing 30 to 34°C 90 sec. Drying 60 to 80°C 60 sec. [Color developer-A] Pure water 800 ml Ethylene glycol 10 ml N,N-diethylhydroxylamine 10 g Potassium chloride 2 g N-ethyl-N-β-methanesulfonamidoethyl-3-methyl-4-aminoaniline sulfate 5 g Sodium tetrapolyphosphate 2 g Potassium carbonate 30 g Optical brightening agent (4,4'-diaminostilbene disulfonic acid derivative) 1 g Pure water added to make a total of 1 liter pH adjusted to pH 10.2 [Bleach-fixer-A] Ferric ammonium ethylenediaminetetraacetic acid dihydrate 60 g ethylenediaminetetraacetic acid 3 g Ammonium thiosulfate (a 70% solution) 100 ml Ammonium sulfite (a 40% solution) 27.5 ml pH adjusted with potassium carbonate or glacial acetic acid to pH 7.1 Water added to make a total of 1 liter [Stabilizer] 5-chloro-2-methyl-4-isothiazoline-3-one 1 g 1-hydroxyethylidene-1,1-diphosphonic acid 2 g Water added to make a total of 1 liter pH adjusted with sulfuric acid or potassium hydroxide to pH 7.0 As is obvious from Table-1, Samples 1 and 2 are not suitable for rapid processing, because they use an emulsion having a 90 mol% silver bromide content. Comparing Sample 1 with Sample 2, the effect of the compound [S] is not so remarkably displayed. Samples 3 through 35 each using an emulsion having a 90 mol% or higher silver chloride content may basically be able to undergo rapid processing satisfactorily, however, comparative samples 3 to 5, 7, 9 and 11 may not be put into practical use, because the γa value is increased, i.e., toe-contrast is seriously hardened, by the compound of Formula [I]. However excellent contrast characteristics were displayed by each of the samples of the invention, Samples 6, 8, 10 and 12 through 35, each using the compound of Formula [I] and compound [S] in combination. To be more precise, the emulsions each containing a small amount of silver bromide result in an increased effect of compound [S]. Example-2 Preparation of Em-n through Em-q and Em-oq. These emulsions were prepared in such a manner that Em-2 prepared in Example-1 was added to chloroauric acid in an amount of 5x10⁻⁵ mol per mol of the silver halide used and, one minute later, sodium thiosulfate was then added thereto in an amount of 2 mg per mol of the silver halide so as to apply a chemical sensitization and, after completion of the chemical sensitization, a compound of Formula [S] shown in Table-2 was added so as to prepare the objective emulsions. Each of the prepared emulsions was coated over in the same manner as in Example-1 to prepare the respective samples and each of the compounds shown in Table-2 was also added thereto in the course of the coating process so as to serve as a hardening agent. The resulting samples were tested for the following evaluations: [BF contamination resistance test] A color developer [B] was prepared in such a manner that the bleach-fixer [A] used in Example-1 was added to the color developer [A] used also in Example-1 in a proportion of 1.0 ml of the former to 1 liter of the latter. Each of the samples was processed with the color developer [B] in accordance with the color processing steps described in Example-1 and the sensitometric measurements of the samples were taken, respectively. The results are shown in Table-2. In the table, Δγb is the value of a contrast variation range obtained when processing the samples with a color developer [B] into which a bleach-fixer was contaminated and such contrast variation values are expressed in accordance with the value of contrast (γb) as the standard value obtained in the case of processing samples with color developer [A] without contamination by a bleach-fixer. The lower this value is, the greater the BF contamination resistance. A value of γb expressed herein means a value expressed by the product of the reciprocal of the logarithmic difference of each exposure necessary to obtain the densities of 0.8 and 1.8 and the above-mentioned density difference. The greater this value is, the harder the contrast. [pH variation resistance test] A color developer [C] was prepared so as to have the same composition as the above-mentioned color developer [A] and adjusted to have a pH value of 10.6. The samples were processed with the color developer [C] in accordance with the color processing steps described in Example-1 and sensitometric measurements of the processed samples were taken. Results are shown in Table-2. In the table, Δγb is the value of a contrast variation range obtained in the case of processing the samples with color developer [C] having a pH value of 10.6 and such contrast variation values are expressed in accordance with the value of a contrast (γ) as the standard value in the case of processing them with color developer [A] having a pH value of 10.2. The following advantages are obvious from the Table. Namely, every sample of the invention, 15 to 20 and 37 to 45, had an excellent BF contamination resistance and pH variation resistance, as compared with comparative sample 36 containing the comparative compound [S]. In particular, compounds of Formula [SA] displayed an excellent effect on BF contamination resistance and compounds of Formula [SB] displayed an excellent effect on pH variation resistance. Besides the above, the samples each containing the silver halide emulsion to which a gold compound is added were more efficient in the above-mentioned effects and the samples hardened by making use of a chlorotriazine type compound as a hardening agent were also efficient. Further, out of the compounds represented by Formula [SA], the compounds in which Z is oxygen in particular displayed excellent effects, as compared with those in which 2 is sulfur. Example-3 The sample emulsions shown in Table-3 were prepared, respectively, in such a manner that the emulsion, EM-2, was added to a chloroauric acid in an amount of 5x10⁻⁵ mol per mol of the silver halide used therein at 60°C and, one minute later, sodium thiosulfate was added in an amount of 2 mg per mol of the silver halide and the resulting emulsions were chemically sensitized. Five minutes before completion of chemical sensitization, the spectral sensitizers (sensitizing dyes) shown in Table-3 were added and, after completion of chemical sensitization, the compounds of Formula [S] shown in Table-3 were added. The resulting emulsions are shown in Table-3 below. Sample No. Spectral sensitizer Compounds of Formula [S] Em-r [SD-1] Comparative compound-1 Em-s [SD-2] Comparative compound-1 Em-t [SD-3] Comparative compound-1 Em-u [SD-1] S-10 Em-v [SD-2] S-10 Em-w [SD-3] S-10 Em-x [SD-1] S-39 Em-y [SD-2] S-39 Em-z [SD-3] S-39 Next, a multilayered silver halide color photographic light-sensitive material sample No. 46 was prepared onto a polyethylene resin-coated paper in the layer arrangement shown in Table-4. Also, similar sample No. 47 having the same constitution as that of Sample No. 46 was prepared in the same manner as Sample No. 46, except that HQ-4 was added into the 1st, 3rd and 5th layers in an amount of 0.1 mol per mol of the couplers used, respectively. Further, Sample No. 48 was prepared in the same manner as Sample No. 47, except that the blue-sensitive emulsion used in the 1st layer of Sample No. 47 was replaced by Em-u, the green-sensitive emulsion of the 3rd layer thereof was replaced by Em-v and the red-sensitive emulsion in the 5th layer thereof was replaced by Em-w, respectively. Still further, Sample No. 49 was prepared in the same manner as Sample No. 48, except that the blue-sensitive emulsion of the 1st layer of Sample No. 48 was replaced by Em-x, the green-sensitive emulsion of the 3rd layer thereof was replaced by Em-y and the red-sensitive emulsion of the 5th layer thereof was replaced by Em-z, respectively. Into every Sample of No. 46 through No. 49, exemplified compound [HD-2] was added in an amount of 10 mg per g of gelatin used. Layer Composition 7th layer Gelatin (1.0 g/m²) 6th layer UV absorbing agent (UV-1, 0.3 g/m²) Gelatin (0.7 g/m²) 5th layer Red-sensitive silver chlorobromide emulsion (Em-t, Silver coated: 0.25 g/m²) Cyan coupler (CC-1, 0.3 g/m²) Dibutyl phthalate (0.2 g/m²) Gelatin (1.0 g/m²) 4th layer UV absorbing agent (UV-1, 0.7 g/m²) Gelatin (1.3 g/m²) 3rd layer Green-sensitive silver chlorobromide emulsion (Em-s, Silver coated: 0.35 g/m²) Magenta coupler (MC-1, 0.4 g/m²) Dibutyl phthalate (0.2 g/m²) Gelatin (1.5 g/m²) 2nd layer Gelatin (1.0 g/m²) 1st layer Blue-sensitive silver chlorobromide emulsion (Em-y, Silver coated: 0.40 g/m²) Support UV absorbing agent (UV-1) The sensitometric evaluation of each sample was made in accordance with the method described in Example-1 and the following color turbidity tests thereof were also carried out. Results are shown in Table-5. 〈Color turbidity evaluation〉 Each sample was exposed to blue light through an optical wedge and was then color processed in accordance with the method described in Example-1. Density measurements were taken, in which a green density obtained when the blue density was 1.0 was designated as D G . The yellow dyes formed from the yellow couplers have some absorption in the green spectral region. Therefore the equation D G =0, is not established even if no color turbidity is produced at all, but D G was of the order of about 0.2 in the evaluation system of the invention. However, when density D G is higher than that of the order of about 0.2, it is possible that color turbidity is caused by the oxidized products of a color developing agent produced in a blue-sensitive emulsion layer diffusing into the green-sensitive emulsion layer. Silver halide emulsion Compound of Formula [S] (mol/mol AgX) Hydroquinone derivative having Formula [I] (mol/mol coupler) γa DG 46 B Em-r Comp. compound-1 (1x10⁻³) ---- 2.04 (Comparative) G Em-s Comp. compound-1 (1x10⁻³) ---- 2.07 0.56 R Em-t Comp. compound-1 (1x10⁻³) ---- 2.11 47 B Em-r Comp. compound-1 (1x10⁻³) HQ-4 (0.1) 2.45 (Comparative) G Em-s Comp. compound-1 (1x10⁻³) HQ-4 (0.1) 2.48 0.22 R Em-t Comp. compound-1 (1x10⁻³) HQ-4 (0.1) 2.50 48 B Em-u S-10 (1x10⁻³) HQ-4 (0.1) 2.00 (Invention) G Em-v S-10 (1x10⁻³) HQ-4 (0.1) 1.99 0.21 R Em-w S-10 (1x10⁻³) HQ-4 (0.1) 2.02 49 B Em-x S-39 (1x10⁻³) HQ-4 (0.1) 2.03 (Invention) G Em-y S-39 (1x10⁻³) HQ-4 (0.1) 1.98 0.21 R Em-z S-39 (1x10⁻³) HQ-4 (0.1) 2.03 As is obvious from Table-5 with respect to Sample No. 46 in which a comparative compound [S] was present but no compound of Formula [I] was present, a serious color turbidity was found, therefore, the sample cannot be put to practical use. With respect to Sample No. 47 in which a compound of Formula [I] was present, the toe-contrast was seriously hardened, although color turbidity was improved, therefore, this sample also cannot be put to practical use. On the other hand, it is shown that, with respect to inventive Samples 48 and 49 in which the compound of Formula [I] and the compound [S] are used in combination, color turbidity production can be inhibited and excellent toe-contrast characteristics can also be achieved.

Claims: A silver halide photographic light-sensitive material comprising a support bearing at least one silver halide emulsion layer containing a dye-forming coupler and a compound of formula [I], wherein at least one of the silver halide emulsion layers contains silver halide grains having a silver chloride content of at least 90 mol% and a compound of formula [S]; wherein, R₂₁, R₂₂, R₂₃ and R₂₄ are, independently, hydrogen, a halogen, alkyl, alkenyl, aryl, cycloalkyl, alkoxy, aryloxy, alkylthio, arylthio, acyl, alkylacylamino, arylacylamino, alkylcarbamoyl, arylcarbamoyl, alkylsulfonamido, arylsulfonamido, alkylsulfamoyl, arylsulfamoyl, alkylsulfonyl, arylsulfonyl, nitro, cyano, alkyloxycarbonyl, aryloxycarbonyl, alkylacyloxy or arylacyloxy, provided that at least one of R₂₁ and R₂₃ has at least three carbon atoms; wherein Q₁ is a group which, together with the carbon and nitrogen to which it is attached, completes a 1,3,4-oxadiazole ring, a 1,3,4-thiadiazole ring or a 1,3,5-triazine ring; and M₁ is hydrogen, an alkali metal or ammonium. A silver halide photographic light-sensitive material according to claim 1 wherein the compound of formula [S] is of formula [SA]; wherein Z is oxygen or sulfur; R A is hydrogen alkyl, aryl, alkenyl, cycloalkyl, -SR A1 , -NHCOR A3 , -NHSO₂R A4 or a heterocyclic group, in which R A1 and R A2 are, independently, hydrogen, alkyl or aryl; R A3 and R A4 are, independently, alkyl or aryl; and M₂ is hydrogen, an alkali metal or ammonium; or the compound of formula [S] is of formula [SB] wherein R A is hydrogen, alkyl, aryl, alkenyl cycloalkyl, -SR A1, -NHCOR A3 , -NHSO₂R A4 or a heterocyclic group, in which R A1 and R A2 are, independently, hydrogen, alkyl or aryl; R A3 and R A4 are, independently, alkyl or aryl; M₃ is hydrogen, an alkali metal or ammonium; and R B1 and R B2 are, independently, hydrogen, alkyl or aryl. A silver halide photographic light-sensitive material according to claim 2 wherein Z is oxygen. A silver halide photographic light-sensitive material according to any one of claims 1 to 3 wherein the silver halide grains comprise silver bromide in a proportion of from 0.05 to 5 mol%. A silver halide photographic light-sensitive material according to any one of claims 1 to 4 wherein the silver halide grains comprise a gold compound. A silver halide photographic light-sensitive material according to claim 5 wherein the gold compound is present in an amount of from 10⁻⁸ mol to 10⁻¹ mol per mol of silver halide. A silver halide photographic light-sensitive material according to claim 6 wherein the gold compound is present in an amount of from 10⁻⁷ mol to 10⁻² mol per mol of silver halide. A silver halide photographic light-sensitive material according to any one of claims 5 to 7 wherein the gold compound is potassium chloroaurate, auric trichloride, potassium auric thiocyanate, potassium iodoaurate, tetracyanauric aside, ammonium aurocyanate, pyridyltrichloroaurate, auric sulfide or auric selenide. A silver halide photographic light-sensitive material according to any one of claims 1 to 8 wherein the compound of formula [I] is of formula [II] or [III]; wherein R₁ and R₂ are, independently, alkyl, aryl, alkenyl, cycloalkyl or a heterocyclic group; wherein R₃ and R₄ are, independently, alkyl having 1 to 5 carbon atoms; R₅ is alkyl, aryl, alkenyl, cycloalkyl, a heterocyclic group, or wherein n is an integer of from 1 to 20; k is 1 or 2; and Q₂ and Q₃ are, independently, -COXR₆ in which X is oxygen or in which R₆ is hydrogen, alkyl, alkenyl, cycloalkyl or aryl; and R₇ is hydrogen, alkyl or aryl; -OY, in which Y is, independently, as defined for -R₆, or -COR₆; in which R₇ is as defined above and R₈ is a hydrogen, alkyl, aryl or -COR₆; -P(O)(OR₆)([O] ℓ R₉) in which R₉ is, independently, as defined for R₆; and ℓ is 0 or 1; or a cyano group. A silver halide photographic light-sensitive material according to any one of claims 1 to 9 wherein the dye-forming coupler is: a yellow dye-forming coupler of formula [Y]; wherein R 1Y is a halogen or alkoxy; R 2Y is hydrogen, a halogen or alkoxy; R 3Y is acylamino, alkoxycarbonyl, alkylsulfamoyl, arylsulfamoyl, arylsulfonamido, alkylureido, arylureido, succinimido, alkoxy or aryloxy; and Z 1Y is a group capable of splitting off in a coupling reaction with an oxidized product of a color developing agent; or a magenta dye-forming coupler of formula [P] or [a]: wherein Ar is aryl; R p1 is hydrogen or a substituent; R p2 is a substituent; Y is hydrogen or a group capable of splitting off in a reaction with the oxidized product of a color developing agent; W is -NH-, -NHCO- in which the N atom is able to couple to a carbon atom of a pyrazolone nucleus, or -NHCONH-; and m is 1 or 2; wherein Za is a group which, together with the carbon and nitrogen to which it is attached, completes a nitrogen-containing heterocyclic ring, which may have a substituent; X is hydrogen or a group capable of splitting off in a reaction with the oxidized product of a color developing agent; and Ra is hydrogen, a halogen, alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, aryl, a heterocyclic group, acyl, sulfonyl, sulfinyl, sulfonyl, carbamoyl, sulfamoyl, cyano, a spiro-compound residue, an organic hydrocarbon compound residue, alkoxy, aryloxy, heterocyclicoxy, siloxy, acyloxy, carbamoyloxy, amino, acylamino, sulfonamido, imido, ureido, sulfamoylamino, alkoxycarbonylamino, aryloxycarbonylamino, alkoxycarbonyl, aryloxycarbonyl, alkylthio, arylthio or heterocyclicthio; or a cyan dye-forming coupler of formula [E] or [F]; wherein E 1E is aryl, cycloalkyl or a heterocyclic group; R 2E is alkyl or phenyl; R 3E is hydrogen, a halogen, alkyl or alkoxy; and Z 1E is hydrogen or a group capable of splitting off in a reaction with the oxidized product of an aromatic primary amine type color developing agent; wherein R 4F is alkyl; R 5F is alkyl; R 6F is hydrogen, a halogen or alkyl; and R 2F is a hydrogen or a group capable of splitting off in a reaction with an oxidized product of an aromatic primary amine type color developing agent. A silver halide photographic light-sensitive material according to any one of claims 1 to 10 wherein the silver halide emulsion layer is hardened using a chlorotriazine hardening agent of formula [HDA] or [HDB]; wherein R d1 is chlorine, hydroxy, alkyl, alkoxy, alkylthio, -OM₄ in which M₄ is a monovalent metal, -NR'R'' in which R' and R'' are, independently, hydrogen, alkyl or aryl or -NHCOR''' in which R''' is hydrogen, alkyl or aryl; and R d2 is, independently, a group as defined for R d1 with the exception of chlorine; wherein R d3 and R d4 are, independently, chlorine, hydroxy, alkyl, alkoxy or -OM₅ in which M₅ is a monovalent metal; Q₄ and Q₄' are, independently, a bonding group indicating -O-, -S- or -NH-; L is alkylene or arylene; and ℓ and m are, independently, 0 or 1.

Inventors: KAJIWARA, MAKOTO KONISHIROKU PHOTO, MIYOSHI, MASANOBU KONISHIROKU PHOTO, ONODERA, KAORU KONISHIROKU PHOTO, SAKAMOTO, EIICHI KONISHIROKU PHOTO
Applicants: KONICA CORPORATION
Application year: 1987
Main classification: G03C7
IPC codes: G03C7, G03C1