JP2522682B2 - Highly sensitive silver halide photographic material - Google Patents

Description

The present invention relates to a highly sensitive silver halide photographic light-sensitive material, and more specifically, it has achieved high sensitivity without causing fog rise and image roughness. The present invention relates to a silver halide photographic light-sensitive material.

[Background of the Invention]

Increasing the sensitivity of a silver halide photographic light-sensitive material is a permanent problem in the photographic industry.

Various means have been proposed to increase the sensitivity by improving the silver halide grains, but even if the sensitivity is increased, pressure fog increases, and when putting it in the actual production process, it involves a large-scale process modification work. Often.

Further, there is a means for increasing the sensitivity by improving the chemical sensitization method, but this means has a problem that the fog increases and the storage fog increases.

In addition, there are known means for using a silver halide solvent such as thioether and a polyethylene oxide called iodine ion scavenger. According to this method, although the sensitization is performed, the image quality is deteriorated. .

[Object of the Invention]

An object of the present invention is to provide a silver halide photographic light-sensitive material which has high sensitivity, has a small fog, and is free from image roughness.

[Means for Solving Problems] The above object is achieved by incorporating a compound in which the amino group portion of an amino acid alkyl ester is an amide bond at the carboxy terminal of a hydrolyzed protein into a silver halide photographic light-sensitive material. it can.

The silver halide photographic light-sensitive material of the present invention contains the above-mentioned compound, and can achieve high sensitivity without causing fog rise and image roughness.

 Hereinafter, the present invention will be described in more detail.

First, a compound in which the amino group portion of an amino acid alkyl ester is amide-bonded to the carboxy terminus of the hydrolyzed protein used in the present invention (hereinafter appropriately referred to as "the compound of the present invention, or since this compound can be used as an emulsifier, The term “protein emulsifier of the present invention” and the like) will be described.

The compound (protein emulsifier) of the present invention can be obtained, for example, by the following production method.

That is, as shown below, the protein-based emulsifier of the present invention can be obtained by first synthesizing an amino acid alkyl ester and then enzymatically reacting the amino acid alkyl ester with a hydrophilic protein.

Synthesis of Amino Acid Alkyl Ester An amino acid alkyl ester is obtained by reacting an amino acid with an alcohol and performing an esterification reaction.

Examples of amino acids that can be used include glycine, leucine, phenylalanine, and alanine, and these can be used alone or in combination.

As the amino acid, it is desirable to use one having high hydrophobicity and less branching in the alkyl group portion in order to improve the reactivity of the enzymatic reaction (aminolysis reaction) in the next step. Others tend to lower the yield of protein-based emulsifiers. Particularly, these amino acids are preferably L-type (natural type). The D type (synthetic type) tends to be inferior in yield.

Examples of alcohols that can be used include those having less than 14 carbon atoms, such as hexanol, octanol, decanol, and dodecanol. Examples of those having 14 or more carbon atoms include the following alcohols.

(Linear saturated alcohol) Myristyl alcohol, cetyl alcohol, stearyl alcohol, aralkyl alcohol (linear unsaturated alcohol) Oleyl alcohol (isoalcohol) 2-hexyldecanol Isostearyl alcohol 2-octyldodecanol When an alcohol having less than 14 carbon atoms is used as a raw material for an amino acid alkyl ester, the resulting protein-based emulsifier has a slightly offensive odor when stored at high temperature for a long time (for example, 6 months at 45 ° C). Tends to occur. If this is disliked, it is preferable to use an alcohol having 14 or more carbon atoms. However, alcohols having 14 or more carbon atoms are difficult to dissolve in the solvent during the subsequent enzymatic reaction,
The reaction tends to be difficult to proceed. Therefore, when the one having 14 or more carbon atoms is used, it is preferable to use the unsaturated one or the branched one. This is because these have high solubility in a solvent, and thus the reaction in the enzyme reaction pattern is likely to proceed.

However, when the one having more than 20 carbon atoms is used, the solubility is insufficient even if the above-mentioned one is used, and the enzymatic reaction is difficult to proceed. Therefore, from the viewpoint of reactivity, it is preferable to use one having 20 or less carbon atoms.

Enzymatic reaction The amino acid alkyl ester obtained as described above is reacted with a hydrophilic protein in the presence of endopeptidase.

Examples of hydrophilic proteins that can be used include casein,
Gelatin, sericin, soluble collagen, zein, serum albumin, lactalbumin, ovalbumin and the like can be used alone or in combination. Of these proteins, proteins other than sericin are sold as reagents. Further, sericin can be obtained by extracting hot water from cocoons and freeze-drying.

The following can be mentioned as an endopeptidase which can be used. That is, the endopeptidase used in the enzymatic reaction has an action of cleaving the protein from its central portion, and it includes serine protease, thiol protease, carboxyl protease, metalloprotease, and other endopeptidases.
Of these, it is most preferable to use thiol protease. Examples of this thiol protease include papain, cathepsin B, promeline, chymopapain, cathepsin L, yeast protease B, cathepsin S, or TZ-peptidase. These may be used alone or in combination.

When an amino acid alkyl ester and a hydrophilic protein are reacted in the presence of endopeptidase as described above, the hydrophilic protein is cleaved from the center by the action of endopeptidase and decomposed, and at the same time, the amino acid is added to the carboxy terminus of the resulting degradation product. The amino moiety of the alkyl ester is amide-bonded to obtain the desired protein-based emulsifier.

The compound of the present invention can be contained in any layer of the silver halide photographic light-sensitive material, and is preferably used in the silver halide emulsion layer.

Gelatin is advantageously used as the binder or protective colloid of the photographic emulsion used in the present invention, but other hydrophilic colloids can also be used.

The photographic emulsion may contain various compounds for the purpose of preventing fog during the production process of the light-sensitive material, during storage or during photographic processing or for stabilizing photographic performance.

The photographic emulsion layer or other hydrophilic colloid layer of the light-sensitive material of the present invention may contain a coating aid and various surface active agents for various purposes.

The photographic light-sensitive material of the present invention may contain an inorganic or organic hardener in the photographic emulsion layer or other hydrophilic colloid layer.

The photographic light-sensitive material of the present invention can contain a dispersion of a synthetic polymer in a photographic emulsion layer or other hydrophilic colloid layer.

The present invention can be embodied as any silver halide photographic light-sensitive material. For example, a color negative photosensitive material, a color reversal photosensitive material, a monochromatic or multicolor color photosensitive material such as color paper, a direct or indirect X-ray photosensitive material,
It can be applied to black-and-white light-sensitive materials such as lith light-sensitive materials and black-and-white photographing light-sensitive materials.

In the case of a color light-sensitive material, various couplers can be used as desired.

In carrying out the present invention, various anti-fading agents, color image stabilizers, ultraviolet absorbers, water-soluble dyes, anti-foggants and the like can be used.

In the photographic light-sensitive material of the present invention, the photographic emulsion layer and other hydrophilic colloid layers can be coated on the support or on other layers by various coating methods. As the support, any suitable one can be used depending on the desired light-sensitive material.

For the exposure and development of the silver halide photographic light-sensitive material of the present invention, a usual technique can be arbitrarily adopted according to each embodied light-sensitive material.

〔Example〕

Examples of the present invention will be described below. It should be understood that the present invention is not limited to the examples below.

Example 1 (Preparation of Photosensitive Material) A transparent support consisting of an undercoated cellulose triacetate film and having an antihalation layer (containing 0.38 g of black colloidal silver and 3.2 g of gelatin) was prepared.
A sample was prepared by sequentially applying the following layers. In all of the following examples, the amount added to the light-sensitive material was shown per 1 m ² , and the silver halide emulsion and colloidal silver were converted to silver.

 The layers are as follows.

Layer 1 ... 1.3 g of low-sensitivity red-sensitive silver iodobromide (containing 5 mol% of silver iodide) emulsion red-sensitized and 1.3 g of ceratin and 0.7 g of 1-hydroxy-N-as a cyan coupler.
(Δ- (2,4-di-t-aminophenoxy) butyl]-
2-naphthoamide), as a colored cyan coupler.
07 g of 1-hydroxy-4- [4- (1-hydroxy-
δ-acetamido-3,6-disulfo-2-naphthylazo) phenoxy] -N- [δ- (2,4-di-t-aminophenoxy) butyl-2-naphthamide disodium, and 0.07 g of DIR compound A low-sensitivity red-sensitive silver iodobromide emulsion layer containing 0.7 g of tricresyl phosphate (TCP) in which 4-octadecylsuccinimide-2- (1-phenyl-5-tetrazolylthio) -1-indanone was dissolved.

Layer 2 ... for use with 1.2 g of high speed red sensitive silver iodobromide emulsion (containing 6 mol% silver iodobromide), 1.4 g of gelatin and 0.20 g of the cyan coupler used in Layer 1 and 0.02 g of Layer 1 A high-sensitivity red-sensitive emulsion layer containing 0.22 g of TCP in which the colored cyan coupler was dissolved.

Layer 3 ... an intermediate layer containing 0.05 g of n-dibutyl phthalate (DBP) in which 0.05 g of 2,5-di-t-octylhydroquinone (anti-staining agent) was dissolved and 0.7 g of gelatin.

Layer 4 ... 0.90 g of low-sensitivity silver iodide-sensitized silver iodide (containing 5 mol% silver iodide) emulsion and 2.1 g of gelatin and 0.8 g of 1- (2,4,6- Trichlorophenyl) 3-{[α- (2,4-di-t-aminophenoxy) -acetamido] benzamido} -5-pyrazolone, 0.15 g of 1- (2,2,2) as a colored magenta coupler.
4,6-Trichlorophenyl-4- (1-naphthylazo)
-3- (2-chloro-5-octadecenylsuccinimidoaniline) -5-pyrazolone, used in 0.016 g of Layer 1
A slow green sensitive emulsion layer containing 0.95 g of TCP with dissolved DIR compound.

Layer 5: 1.7 g of high-sensitivity green-sensitive silver iodobromide (containing 4 mol% silver iodide) emulsion sensitized to green, 1.9 g of gelatin and
0.60 g dissolved 0.20 g of the magenta coupler used in Layer 4 and 0.049 g of the colored magenta coupler used in Layer 4
High-sensitivity green-sensitive emulsion layer containing DNP.

Layer 6 ... Yellow filter layer containing 0.15 g of yellow colloidal silver, 0.1 g of DBP in which 0.2 g of stain inhibitor (same as contained in layer 3) was dissolved and 1.5 g of gelatin.

Layer 7: 0.25 g of low-sensitivity silver iodobromide (containing 4 mol% silver iodide) emulsion sensitized to blue and 1.9 g of gelatin, and 1.5 g of α-pivaloyl-α-as a yellow coupler.
(1-benzyl-2-phenyl-3,5-dioxoimidazolidin-4-yl) -2'-chloro-5 '-[(α-
Dodecyloxycarbonyl) ethoxycarbonyl] acetanilide dissolved low-sensitivity blue-sensitive emulsion layer containing 0.6 g of TPC.

Layer 8: 0.9 g of high-sensitivity silver iodobromide (containing 2 mol% silver iodide) emulsion sensitized to blue, 1.5 g of gelatin and 1.30 g
0.65 g TCP with dissolved yellow coupler used in Layer 7 of
High-sensitivity blue-sensitive emulsion layer containing.

Layer 9 ... 2.3 g gelatin, 0.05 g betaine Protective layer with 0.1 g KBF ₄ .

 A hardener and a spreading agent were added to each layer.

(Measurement of Sensitometry) The sample was exposed to sensitometry and the fog density, sensitivity, and maximum density were measured when the following development processing was performed.

Development recipe 1. Color development 3 minutes 15 seconds (38 ℃) 2. Bleaching 6 minutes 30 seconds 3. Water washing 3 minutes 15 seconds 4. Fixation 6 minutes 30 seconds 5. Water washing 3 minutes 15 seconds 6. Cheap Normalization 3 minutes 15 seconds The composition of the treatment liquid used in each step is as follows.

(Synthesis of Protein Emulsifier-1) An amino acid alkyl ester was produced as follows, and then subjected to an enzymatic reaction.

Synthesis of amino acid alkyl ester-p-toluenesulfonate 0.05 mol of leucine as an amino acid, 0.055 mol of p-toluenesulfonic acid hydrate, and 0.075 mol of oleyl alcohol as an alcohol, and 100 ml of benzene as a solvent was added to this. The mixture was thoroughly stirred and mixed, and heated to reflux at the reflux temperature of benzene to allow the esterification reaction to proceed. In this case, water generated along with the progress of the esterification reaction comes out in an azeotropic state with benzene, so the reaction was completed in about 5 to 10 hours while removing it from the reaction system. next,
The solvent benzene was removed by concentration under reduced pressure, ether and petroleum ether were added, the produced crystals were collected by filtration, and the obtained crude crystals were recrystallized from acetone, ether, petroleum ether or the like.

Infrared absorption spectrum analysis confirmed that the desired product was obtained. That is, the infrared absorption spectrum of the leucine-oleyl ester obtained here is as shown in FIG. 1, in which peaks are para-substituted phenyl groups, peaks 2 and 3 are ester bonds, peak 4 is sulfonic acid, 5 and 6 are absorptions of primary amine salts.

Enzymatic reaction 82g of hydrophilic protein, gelatin, was dissolved in 200g of 1M carbon buffer (pH 9.0), 50g of acetone was added to the solution, immersed in a 35 ° C warm water bath, and stirred thoroughly. Homogenized. Next, 30 g of the leucine oleyl ester obtained in the above (amount of 1 mol per 1000 g of gelatin) was added and stirred to homogenize. At this time, it is desirable in terms of reaction efficiency to add the amino acid alkyl ester such as leucine oleyl ester at a ratio of 1 mol per 1000 g of hydrophilic protein such as gelatin. Then,
To this, 20 mg of 2-mercaptoethanol was added, and crystalline papain (manufactured by Sigma), which is an endopeptidase, was added.
The reaction was carried out for 60 minutes while adding mg and stirring. Then, the whole pH was adjusted to 2 with 1N hydrochloric acid to stop the reaction, this was put into a cellophane tube as a dialysis tube, dialyzed in running water for 2 days and night, and then freeze-dried.

Next, this is washed with hot acetone to remove unreacted leucine oleyl ester, and the desired protein-based emulsifier is added.
Got 83g. This is designated as protein emulsifier-1.

(Preparation of Test Sample) To the layers 1, 2, 4, 5, 7, and 8 of the sample containing the silver iodobromide emulsion, the protein emulsifier-1 obtained by the above synthesis was added in the amount shown in Table 1. It was In addition, each sample was 55 ℃ at a humidity of 46RH%.
The fog and sensitivity when stored for a day (oven test) are shown. Sensitivity is a relative value with sample No. 1-1 as 100.

From Table 1, it can be seen that the sample of the present invention has a high sensitivity and a small fog.

Example-2 (Preparation of sample) 35 mol% of silver bromide and 65 mol% of silver chloride were contained, and the average particle size was 0.1.
A silver chlorobromide emulsion containing 25μ cubic grains was added at pH 5.5, p
Sodium thiosulfate and chloroauric acid were added under the conditions of Ag8.1 for chemical sensitization, and 200 mg of the following sensitizing dye was added per mol of silver.

4-hydroxy-6-methyl-1,3,3a, 7 as stabilizer
-2 g tetrasilden per mol silver and 34 mg saponin
/ 1 mol silver, styrene-maleic acid copolymer 108 mg / 1 mol silver, 1-hydroxy-3,5-dichlorotriazine sodium salt as a hardener and formalin were added, and on the polyethylene phthalate support of the undercoating agent Was coated on the emulsion layer so as to have a silver content of 3.6 g / m ^2, and as a protective film, gelatin was applied on the emulsion layer so that the gelatin content was 1.1 g / m ² .

(Sensitometry measurement) Wedge exposure and halftone dot exposure were performed in 1 / 100,000 seconds using a xenon light source equipped with a Ratten filter No. 88A.
Using a developing solution and a fixing solution having the following composition, developing with Konica Automatic Processor GR-27 (manufactured by Konica Corporation) at 38 ° C for 20 seconds, fixing, washing with water, and drying to determine sensitivity by measuring optical density, Moreover, the quality of halftone dots was evaluated by visual evaluation.

When the developing solution was used, the entire amount of the developing solution was dissolved in pure water (ion-exchanged water) 3 and used.

The pH of the developer before dilution with water was about 11.4, and the pH of the developer after dilution with water was 10.8.

<Fixer formulation> When the fixing solution was used, the above composition A and composition B were dissolved in this order in 500 ml of water and finished to 1 before use. The pH of this fixer was about 4.3.

(Synthesis of protein emulsifier-2) Glycine myristyl ester was produced as follows, and then this was subjected to enzymatic reaction.

Production of glycine myristyl ester Glycine was used in place of leucine, and myristyl alcohol was used in place of oleyl alcohol. Glycine myristyl ester was obtained in substantially the same manner as in Synthesis-1 of protein emulsifier except for the above.

Enzymatic reaction 30 g of sericin was used in place of 82 g of gelatin, and this was dissolved in 200 g of 1 mol of carbonate buffer. Next, 50 g of acetone was added to this, and the mixture was immersed in a hot water path at 35 ° C. for uniform stirring. Then the glycine myristyl ester obtained above
8.6 g (1 mol per 1000 g of sericin) was added, and the mixture was stirred and homogenized. From this point onward, the synthesis of the protein emulsifier was performed except that the amount of crystalline papain used was reduced to 20 mg.
A protein emulsifier was obtained in the same manner as in 1. This is designated as protein emulsifier-2.

(Preparation of Test Sample) The amount of protein emulsifier-2 shown in Table-2 was added to the emulsion layer at the time of coating. Table 2 shows the relative sensitivity and halftone dot quality of each sample. In addition, the halftone dot quality is a five-level evaluation of visual judgment, 5 is the best, 3 is the practical lower limit, and 1 is the level that is quite bad. From Table 2, it can be seen that the samples of the present invention are good in terms of both sensitivity and fog, have good halftone dot quality, and have no image roughness.

Example 3 (Production of Light-Sensitive Material) Monodispersed silver iodide containing 2 mol% iodine and 0.2 mol% chlorine having an average particle size of 0.3 μ, and 40 mol% iodine and 60 mol% bromine on the inner core and the outside thereof. A silver iodobromide layer is provided at a ratio of
To a grain size of 0.85 .mu.m at a ratio of 1 mol% iodine and 99 mol% bromine, to obtain slightly rounded tetradecahedral silver halide grains.

Chloroauric acid salt, rhodan ammonium, sodium thiosulfate and thiourea compound were added to these particles and chemically aged.

An emulsion preparation liquid was prepared by adding 11 g of trimethylolpropane, a stabilizer and a thickening agent to 70 g of the particles, and further adding betaine. This emulsion preparation liquid and the protective layer liquid described below were mixed with polyethylene at a coating speed of 15 m / min so that the emulsion preparation liquid had a silver amount of 4.8 g / m ² and the protective layer liquid had a gelatin amount of 1.0 g / m ^2. A sample was obtained by simultaneous coating on a terephthalate support and drying for 2 minutes and 30 seconds.

(Measurement of sensitometry) A sample was exposed to a wedge, and the developer and fixer described below were used, and the UX400 automatic developer manufactured by Konica Corporation was used at 90 ° C at 35 ° C.
Processed for seconds.

(Preparation of Test Sample) As shown in Table 3, the protein emulsifier-1 used in Example-1 and the protein emulsifier-2 used in Example-2 were added to the emulsion layer to obtain a coated sample. Table 3 shows the fog and relative sensitivity when each sample was stored at a humidity of 46RH% at 55 ° C for 3 days (oven test).

From Table 3, it can be seen that the samples of the present invention have high sensitivity, small fog, and good results with respect to storage fog.

Example-4 A light-sensitive material having the same structure as that of the above-mentioned Example-1 was prepared as a sample, and the same processing and measurement were performed. However, instead of the protein emulsifier-1, the following protein emulsifier-1-2 was added to make a test sample, and the test sample was provided for evaluation.

(Synthesis of protein emulsifier-1-2) Alanine aliphatic alcohol ester was produced as follows, and then this was subjected to enzymatic reaction.

Synthesis of L-alanine alkyl ester-p-toluene sulfonate L-alanine 4.46 g (0.05 mol), p-toluene sulfonic acid-hydrate 11.4 g (0.06 mol), and myristyl alcohol 11.79 g (0.055) as alcohol. Mol), 200 ml of benzene as a solvent was added thereto, and they were sufficiently stirred and mixed, and heated to reflux at the reflux temperature of benzene to proceed the esterification reaction. In this case, water generated along with the progress of the esterification reaction comes out azeotropically with benzene, so the reaction was completed in about 7 to 15 hours while removing it from the reaction system. Next, the solvent benzene was removed by concentration under reduced pressure, ether and petroleum ether were added, the resulting crystals were collected by filtration, and the obtained crude crystals were recrystallized from acetone, ether, petroleum ether, etc. 21.74 g (yield 95%) of alanine-myristyl ester-p-toluenesulfonate was obtained.

Enzymatic reaction 80g of hydrophilic protein, gelatin, was dissolved in 200g of 1 molar carbon buffer (pH 9.0), 50g of acetone was added to the solution, and it was immersed in a hot water bath at 37 ℃ and stirred thoroughly. Homogenized. Next, 37 g of the L-alanine-myristyl ester-p-toluenesulfonate obtained in this way (amount which becomes 1 mol per 1000 g of gelatin) was added and stirred to homogenize. At this time, it is desirable from the viewpoint of reaction efficiency that the amino acid alkyl ester such as L-alanine-myristyl ester is added at a ratio of 1 mol per 1000 g of hydrophilic protein such as gelatin. Then, 20 mg of 2-mercaptoethanol was added thereto, and further 40 mg of crystalline papain (manufactured by Sigma), which is an endopeptidase, was added thereto and the reaction was carried out for 15 minutes while stirring. And 2
The reaction was stopped by adjusting the total pH to 2 with normal hydrochloric acid, and the reaction was placed in a cellophane tube (dialysis tube) and dialyzed in running water for 2 days and night, and then freeze-dried.

Next, this was washed with hot acetone to remove unreacted L-alanine-myristyl ester to obtain 83 g of a target protein emulsifier. This is designated as protein emulsifier-1-2.

(Preparation of test sample) The protein emulsifiers 1-2 obtained by the above-mentioned synthesis are shown in the layers 1, 2, 3, 4, 7, 8 of the sample containing the silver iodobromide emulsion as shown in Table 1-.
Test sample Nos. 1 to 17 were obtained by adding in the amounts shown in 2. Also, the fog and sensitivity of each sample when stored at a humidity of 46 RH% at 55 ° C for 3 days (oven test) are shown. Sample No. 1 sensitivity
Is a relative value with 100 as.

From Table-1-2, it is understood that the sample of the present invention has high sensitivity and small fog.

Example-5 A light-sensitive material having the same structure as in Example-2 was prepared as a sample, and the same processing and measurement were performed. However, instead of the protein emulsifier-2, the following protein emulsifier-2-2 was added to make a test sample, which was used for evaluation.

(Synthesis of protein emulsifier -2-2) Free L-alanialkyl ester was produced as follows, and then subjected to enzymatic reaction.

Preparation of Free L-Alanine Alkyl Ester Instead of myristyl alcohol, cetyl alcohol 1
L-alanine cetyl ester-p-toluenesulfonate was synthesized in the same manner as in the synthesis of L-alanine alkyl ester-p-toluenesulfonate in Example 1 except that 3.3 g (0.055 mol) was used. . The obtained L-
Toluene sulfonate is again dissolved in 200 ml of benzene,
It was repeatedly treated with 300 ml of 0.1N sodium hydroxide three times. Then, the benzene layer was collected and thoroughly washed with water. After washing with water, collect the benzene layer and add 1 with anhydrous sodium sulfate.
Dried overnight. After drying, the benzene layer was collected by filtration. The solvent of this benzene solution was removed by an evaporator to obtain 14.86 g (yield 94.8%) of a purified oily substance of free L-alanine cetyl ester.

Enzyme reaction 50g of hydrophilic protein, gelatin, was dissolved in 200ml of 1M carbonate buffer (pH 9.0), 50ml of acetone was added to the solution, immersed in 37 ° C warm water bath, and stirred thoroughly. Homogenized. Next, 15.7 g of the L-alanine cetyl ester thus obtained (1 mol per 1000 g of gelatin) was added and sufficiently stirred to homogenize. in this case,
From the viewpoint of reaction efficiency, it is preferable to add the amino acid alkyl ester such as L-alanine cetyl ester in a ratio of 1 mol per 1000 g of hydrophilic protein such as gelatin. Then, 438 mg of L-cystine hydrochloride (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto, and further, 25 mg of papain (manufactured by Sigma), which is an endopeptidase, was added, and the reaction was carried out for 15 minutes while stirring. Then, the whole pH was adjusted to 2 with 2N hydrochloric acid, the reaction was stopped, the reaction was put into a cellophane tube (dialysis tube), dialyzed in running water for 2 days and night, and then freeze-dried. Next, this was washed with hot acetone to remove unreacted L-alanine cetyl ester to obtain 48.9 g of a target protein emulsion. It is a protein-based emulsifier
2-2.

(Preparation of Test Sample) Sample Nos. 18 to 34 were obtained by adding the protein emulsifier -2-2 shown in Table -2-2 in the emulsion layer at the time of coating. The relative sensitivity, fog and halftone dot quality of sample No. 18 of each sample are shown as 100. In addition, the halftone dot quality is a five-level evaluation of visual judgment, 5 is the best, 3 is the practical lower limit, and 1 is a level that is quite bad. From Table-2-2, it can be seen that the sample of the present invention is good in terms of both sensitivity and fog, has good halftone dot quality, and has no image roughness.

Example-6 A light-sensitive material having the same structure as that of Example-3 was prepared as a sample, and the same processing and measurement were performed.

 The test sample was prepared as follows.

(Preparation of Test Sample) As shown in Table 3-2, the protein emulsifier-1-2 used in Example-4 and the protein emulsifier-2-2 used in Example-5 were added to the emulsion layer, A coated sample was obtained. Also, the fog and relative sensitivity of each sample when stored at a humidity of 46 RH% at 55 ° C for 3 days (oven test) are shown.

From Table 3, it can be seen that the samples of the present invention have high sensitivity, small fog, and good results with respect to storage fog.

[Effects of the Invention] As described above, the silver halide photographic light-sensitive material according to the present invention has high sensitivity, low fog, and little image roughness.

[Brief description of drawings]

FIG. 1 is a diagram showing an infrared absorption spectrum of leucine oleyl ester obtained in Examples.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Umeji Murakami 5-16-5, Kotobuki-cho, Odawara-shi, Kanagawa (72) Inventor Soichi Arai 38-38, Nanajima-cho, Kanagawa-ku, Yokohama (56) References JP 60-97043 (JP, A) JP 62-227145 (JP, A) JP 62-138849 (JP, A) JP 62-4275 (JP, A) JP 61-34139 (JP, B2) Japanese Patent Publication 4-63663 (JP, B2)

Claims (1)

(57) [Claims] 1. A silver halide photographic light-sensitive material comprising a hydrophilic protein hydrolyzate containing a compound in which the amino group portion of an amino acid alkyl ester is amide-bonded to the carboxy terminus.