JPH042173B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improved silver halide photographic material, and more particularly to a silver halide photographic material having improved printability, comprising a hydrophobic support with antistatic properties and a coating weight suitable for pencil rewriting, and a silver halide photographic constituent layer. The present invention relates to a silver halide photographic material produced by the present invention. Usually, a silver halide photographic material is composed of a support and a silver halide photographic constituent layer provided on the support. Such silver halide photographic constituent layers include a silver halide photographic emulsion layer, a protective layer, a subbing layer, an intermediate layer or color mixing prevention layer, an antihalation layer or filter layer, an ultraviolet absorbing layer, etc., and combinations thereof. It is what was done. For example, a single silver halide photographic material is
A silver halide emulsion layer and its protective layer are provided on a support. In addition, a multilayer silver halide color photographic material has a multilayer arrangement in which a blue-sensitive emulsion layer and an intermediate layer, a green-sensitive emulsion layer and an ultraviolet absorbing layer, a red-sensitive emulsion layer and a protective layer, etc. are sequentially provided on a support. Each color-sensitive emulsion layer contains yellow, magenta, and cyan color forming couplers. Incidentally, supports for silver halide photographic materials have conventionally been made of films such as polyethylene terephthalate film, cellulose triacetate film, polystyrene film, polycarbonate film, paper as a substrate, and resins capable of forming films on both sides, often polyolefin resins. Hydrophobic supports such as resin-coated papers coated with In particular, polyolefin resin-coated paper is increasingly being used as a support for photographic printing paper in place of the conventionally used baryta paper. The reason for this is that the polyolefin resin-coated paper used as a photographic support is hydrophobic.
This is because, compared to baryta paper, processing liquid is less likely to penetrate into the base paper layer during development and fixing of photographic paper, and therefore processing times such as washing and drying are shortened. However, these photographic hydrophobic supports have several drawbacks. A well-known drawback is that silver halide photographic materials with these hydrophobic supports tend to become statically charged and attract dirt, dust, etc. during their handling.
In addition to causing various spots such as water repellency, desensitization, and fogging, the accumulated static electricity is discharged, resulting in photographic properties called static marks in the silver halide photographic emulsion layer. Moreover, it may cause extremely unpleasant partial fogging. Furthermore, silver halide photographic materials with these hydrophobic supports do not have the ability to write on the back surface, especially with a pencil, so consumers who have become familiar with conventional silver halide photographic materials that use baryta paper as a support It has become extremely inconvenient for people. For this purpose, a coating layer called a back coat layer with antistatic properties and pencil retouchability is installed on the back side of the silver halide photographic material having a hydrophobic support, that is, on the surface of the support that is not coated with the silver halide photographic constituent layer. It is known to do. For example, in order to provide antistatic performance,
The use of colloidal silica described in Japanese Patent Publication No. 30298, colloidal alumina described in Japanese Patent Publication No. 52-18020, and compounds having various carboxyl groups described in Japanese Patent Publication No. 58-9408 is known. . In addition, ethylene maleic anhydride copolymer described in Japanese Patent Publication No. 57-12980;
69139, a water-soluble polymer compound obtained by copolymerizing an ethylenically unsaturated copolymerizable monomer having 4 or more carbon atoms with maleic anhydride, or a salt thereof, Japanese Patent Publication No. 57-53940 It is also known to use organic polymer antistatic agents such as the water-soluble film-forming polymeric anionic polymer electrolytes described in No. In addition, in order to allow addition with a pencil, for example, barium sulfate as described in Japanese Patent Publication No. 57-53940, silicon dioxide oxide, calcium carbonate as described in Japanese Patent Publication No. 57-118241, etc. , magnesium carbonate, titanium oxide, aluminum oxide,
The use of fine particles of barium sulfate, glass powder, etc. is known. However, when using silver halide photographic materials consisting of a hydrophobic support provided with these back coat layers and silver halide photographic constituent layers,
It had one or more serious shortcomings. For example, when used in high-sensitivity silver halide photographic materials, it may not be possible to sufficiently prevent static marks, or the antistatic performance may deteriorate after processing, causing prints to stick to each other, making handling inconvenient. Some of the components may detach, resulting in undesirable sludge build-up, or the back coat layer may be fragile or have weak adhesion to the hydrophobic resin, causing the interior of the printer to be damaged during exposure of silver halide photographic materials. There were cases in which the coating equipment was contaminated with powder, and the coating equipment was contaminated at the stage of coating the silver halide photographic constituent layers. In addition, as is often done in recent years, halogenation is carried out in printers for the purpose of automatically cutting roll-shaped silver halide photographic materials by clearly marking the boundaries between the screens, or for the purpose of writing information about the screens. Type printing is sometimes carried out on the back coat layer on the back side of silver photographic materials, but problems have arisen in that the type ink is washed away in the processing bath or the color becomes diluted, making it impossible to fully demonstrate its function. In particular, in the case of multilayer silver halide color photographic paper, most of which is automatically printed and automatically cut in roll form, the ability to print on the back coat layer in the printer is an important characteristic.
There has been a strong demand for a multilayer silver halide color photographic paper in which the back coat layer is clearly printed even after development. By the way, type printing as used in this specification refers to a process in which a substrate such as a type ribbon containing ink is interposed between the back coat layer surface of a silver halide photographic material and a type consisting of dots or inscriptions, and the type is pressed. Therefore, it is preferable that the ink be printed in the form of a type on the surface of the back coat layer by an impact method. Furthermore, as already mentioned, silver halide photographic materials having a hydrophobic support are characterized by shortened development processing time and so-called rapid processing properties. However, if a silver halide photographic material having a hydrophobic support with a back coat layer on which type printing has been applied is developed after 60 minutes or more, especially 3 hours or more, after type printing, Although it is possible to obtain prints with clear type imprinting even after processing,
Within 60 minutes, the shorter the elapsed time after type printing, the worse the type printability after development, and in extreme cases, almost no type print remains. It has been found that serious problems arise which are completely contrary to the benefit of rapid processability of silver halide photographic materials. In addition, in silver halide photographic materials having a hydrophobic support provided with a back coat layer containing fine particles, especially inorganic fine particles, in order to provide pencil-editability (hereinafter simply referred to as pencil-editability), , the silver halide photographic layer surface is damaged,
Unpleasant unevenness of gloss sometimes occurred. Accordingly, a first object of the present invention is to provide an improved silver halide photographic material having a hydrophobic support provided with a backcoat layer. That is,
It is sufficiently anti-static and therefore prevents the formation of static marks, prevents prints from sticking to each other after processing, and does not contaminate the processing bath, printer, etc. A further object of the present invention is to provide a silver halide photographic material having a hydrophobic support provided with a back coat layer, in which type impressions made on the surface of the back coat are clearly visible even after development. The second object of the present invention is to provide a method which has excellent rapid processing properties, in which type impressions made on the surface of the back coat layer in the printer are clearly visible even after development processing.
The object of the present invention is to provide a multilayer silver halide color photographic material having a hydrophobic support provided with a backcoat layer. A third object of the present invention is to prevent unpleasant gloss unevenness from occurring on the surface of the silver halide photographic constituent layer.
Can be added with a pencil on the back coat layer surface.
The object of the present invention is to provide a silver halide photographic material having a hydrophobic support provided with a backcoat layer. Other objects, features, advantages, etc. of the present invention will be understood from the following description. As a result of intensive studies, the present inventors found that the first aspect of the present invention,
The second object is to have a silver halide photographic constituent layer on one side of a hydrophobic support, and at least a) a polymer latex and b) on the opposite side of the support.
having a back coat layer containing colloidal silica;
In addition, the polymer latex contains (a) 1.0 to 5.0% by weight of acrylic acid or methacrylic acid, (b) 5.0 to 20% by weight of styrene sulfonic acid, and the remaining weight% of (c) acrylic acid. obtained by copolymerization of lower alkyl ester and (d) styrene, and (c) acrylic acid lower alkyl ester pair (d)
It has been found that this can be achieved by using a copolymer or an acid-neutralized emulsion thereof in which the weight composition of styrene is 1.0:1.0 to 2.0:1.0. It has also been found that the third object of the present invention can be achieved by further incorporating c) a matting agent into the back coat layer containing a) polymer latex and b) colloidal silica. The silver halide photographic material according to the present invention does not produce unpleasant partial fog called static marks. Also, developing, fixing (or bleach-fixing),
Even if you stack them after washing and drying them, they will not stick to each other due to static electricity and become difficult to handle. The silver halide photographic materials of the present invention do not contaminate processing baths, printers, etc. with backcoat coating compositions. In the silver halide photographic material according to the present invention, the type imprint on the back side does not disappear or become thinner during processing so that it no longer plays its role, and even after processing, the type is clearly visible. An impression is obtained. Furthermore, the silver halide photographic material according to the present invention in which the back coat layer contains a matting agent has particularly excellent pencil retouchability, and a small amount of mattifying agent is required to obtain the same level of pencil retouchability. This eliminates unpleasant gloss unevenness on the front surface. The polymer latexes used in the practice of the present invention include Cevian-A46704, Cevian-A46704, and Cevian-A46704.
Trade names such as A46739 (manufactured by Daicel Chemical Industries, Ltd.) are known. The coating amount starts from 1mg/ ^m2 in terms of solid content.
300mg/ ^m2 , preferably 7.5mg/ ^m2 to 75
A range of mg/ ^m2 is good. If the coating amount is too small, the necessary antistatic performance cannot be obtained, and if the coating amount is too large, the condition of the coated surface will deteriorate. The colloidal silica used in the practice of the present invention is mainly composed of silicic anhydride (SiO ₂ ) using water as a dispersion medium.
It is a colloidal solution made by dispersing ultrafine particles in water. Further, the dispersion medium is generally water, but methanol or the like may be used in some cases. The colloid solution also contains an alkaline component for purposes such as a colloid stabilizer. For example, in addition to Na ₂ O, it may also contain NH ₃ , formamide, ethylamine, morpholine, etc. The colloidal silica preferably used in the practice of the present invention is preferably colloidal silica with an average particle size of 5 mμ to 100 mμ, and the coating amount is 10 mμ in terms of solid content.
mg/ ^m2 to 1.0g/ ^m2 , preferably 0.03
A range of g/m ² to 0.3 g/m ² is good. If the particle size of colloidal silica is too small, it tends to gel, and if it is too large, the silica particles will settle and cannot be stably obtained as colloidal silica. If the coating amount is too small, the necessary antistatic performance cannot be obtained, and if the coating amount is too large, the scratch resistance and printability of the coating film will not be sufficiently improved. A specific example of colloidal silica is Snotex manufactured by Nissan Chemical Co., Ltd. The matting agent preferably used in the practice of the present invention has an average particle size of 0.2μ to 10μ, preferably
Powders that are 0.3μ to 5μ are useful. Specific examples include silicon dioxide, calcium carbonate,
Examples include fine particles of magnesium carbonate, titanium oxide, precipitated aluminum hydroxide, barium sulfate, strontium sulfate, acrylic resin, polystyrene, rice starch, and the like. If the particle size of the matting agent is too small or the amount applied is too small, the pencil retouchability will be insufficient, and if the particle size is too large or the amount applied is too large, the texture will be unpleasant. This results in undesirable scratches on the surface. Therefore, the coating amount is preferably in the range of 5 mg/m ² to 500 mg/m ² , preferably in the range of 12 mg/m ² to 150 mg/m ² . In the back coat layer according to the present invention, a compound having two or more ethyleneimino groups or glycidyl ether groups in the molecule is contained as a curing agent for the purpose of improving the hardness or scratch resistance of the layer. It's advantageous. Specific examples of those curing agents are shown below. Additionally, those curing agents can be used in suitable solvents such as water, methanol, ethanol,
It is advantageous to dissolve it in N,N-dimethylformamide, acetone, ethyl acetate, etc. and incorporate it into the back coat layer. In addition, the content of these curing agents ranges from 2.0% to 100% by weight based on the polymer latex.
A range of from 10% to 50% by weight is particularly preferred. In carrying out the present invention, different types of latexes can be used in combination as appropriate for various purposes such as adjusting the physical properties of the film and improving the adhesion to the support. Such polymer latex has an average particle size of 20 mμ ~
It is an aqueous dispersion of a 200 mμ water-insoluble polymer, and various types can be used including acrylic latex, vinyl acetate latex, styrene-butadiene latex, acrylonitrile-butadiene latex, etc. In addition, in carrying out the present invention, various water-soluble materials such as polyvinyl alcohol, poly-N-vinylpyrrolidone, starch paste, starch derivatives, cellulose derivatives, Guams, and polymers having sulfonic or carboxyl groups may be used to improve coating properties or for other purposes. Can be used in combination with a synthetic polymer. However, it is not desirable to use too much of these water-soluble polymers since they deteriorate film strength and type printability.
In particular, water-soluble polymers having sulfonic groups or carboxyl groups, or water-soluble polymers commonly called antistatic agents, cause significant deterioration in film strength and deterioration in type printability. Since the antistatic effect of the present invention is excellent, not only is it not necessary to use a water-soluble antistatic agent in combination for normal purposes, but it is also not necessary to use a water-soluble antistatic agent at all, or in the case where it is used in combination, the amount used is as low as possible. It is desirable to keep it in small amounts. Another preferred embodiment of the invention includes a)
Of the total amount of monomers, 1.0 to 5.0% by weight of acrylic acid or methacrylic acid, (b) 5.0 to 20% by weight of styrene sulfonic acid, and the remaining weight% of (c) acrylic acid lower alkyl ester and (d) styrene. (c) a copolymer or an acid neutralized product thereof having a weight composition of (c) acrylic acid lower alkyl ester to (d) styrene in a range of 1.0:1.0 to 2.0:1.0, and (b) colloidal silica. There are silver halide photographic materials having a back coat layer consisting of e) gelatin and f) a non-formalin gelatin hardener. Gelatin has high reactivity with various crosslinking agents, and various special hardening agents have been designed for use in photographic emulsions. When this gelatin is used in combination with a special hardening agent, water resistance can be dramatically improved compared to other water-soluble polymers, and it can be used without introducing the disadvantages of other water-soluble polymers. . However, among gelatin hardening agents, aldehyde-based ones have disadvantages such as contamination of the back coat layer. In particular, formalin or a compound that liberates formalin cannot be used because it will fog the photographic emulsion or, if the silver halide photographic material is a color photographic material, it will react with the coupler and cause unpleasant discoloration. Various types of hydrophobic supports can be used in the practice of the present invention. For example, using paper as a substrate, polyolefin, polystyrene,
Examples include resin-coated paper coated with a film-forming resin such as polyvinyl chloride, often a polyolefin resin. In particular, polyolefin resin-coated paper is advantageously used as a support for photographic paper, especially color photographic paper, which requires good type printability, in that the effects of the present invention are more prominently exhibited. . In addition, the resin layer of these resin-coated papers contains white pigments such as titanium oxide, zinc oxide, talc, and calcium carbonate, fatty acid amides such as stearic acid amide and arachidic acid amide, zinc stearate, magnesium stearate, and palmitin. It is preferable to contain various additives such as dispersants such as fatty acid metal salts such as calcium acid salts, pigments and dyes such as ultramarine and cobalt violet, antioxidants, fluorescent brighteners, and ultraviolet absorbers in appropriate combinations. . The polyolefin resin-coated paper which is advantageously used in the practice of the present invention is manufactured by extrusion coating a molten polyolefin resin onto a running base paper through a slit die in the form of a film. At that time, it is desirable to activate the base paper surface by corona treatment, flame treatment, etc. prior to melt extrusion coating. The thickness of the coating resin layer is not particularly limited, but it is generally advantageous to have a thickness of about 5μ to 50μ. The side of the polyolefin resin-coated paper on which the silver halide photographic constituent layer is provided has a glossy surface, matte surface, silky surface, etc. depending on the purpose, and the back surface is usually a matte surface. The polyolefin resin for coating the polyolefin resin-coated paper that is advantageously used in the practice of the present invention includes homopolymers of olefins such as low density polyethylene, high density polyethylene, polypropylene, polybutene, polypentene, etc.
Examples include copolymers made of two or more olefins, such as propylene copolymers, and mixtures thereof, with various densities and melt viscosity indexes (hereinafter simply referred to as MI), either singly or in mixtures. It can be used as The base paper for polyolefin resin-coated paper may be ordinary natural pulp paper, synthetic fiber paper, or so-called synthetic paper made of synthetic resin film, but wood pulp such as softwood pulp, hardwood pulp, or mixed softwood and hardwood pulp may be used. Natural pulp paper based on is advantageously used. There are no particular restrictions on the thickness of the base paper, but paper with good surface smoothness is preferred, and its basis weight is preferably 50 g/m ² to 250 g/m ² . Also,
The base paper whose main component is natural pulp can contain various polymeric compounds and additives.
For example, starch derivatives, polyacrylamide,
Dry paper strength enhancers such as polyvinyl alcohol derivatives and gelatin, sizing agents such as fatty acid salts, rosin derivatives, and dialkyl ketene dimer emulsions, wet paper strength enhancers such as melamine resins, urea resins, and epoxidized polyamide resins, stabilizers, Pigments, dyes, fluorescent whitening agents, latex, inorganic electrolytes, PH adjusters, etc. can be contained in appropriate combinations. The back coat layer according to the present invention can contain various polymer compounds and additives. Water-soluble polymers include starch derivatives such as oxidized starch and phosphated starch, polyvinyl alcohol, polyacrylamide, poly-N-vinylpyrrolidone, agar, and sodium alginate. Surfactants include alkylbensulfonates and sulfosuccinates. Anionic surfactants such as acid ester salts, nonionic surfactants such as saponins and alkylene oxide compounds, amphoteric surfactants such as amino acids, aminosulfonic acids, and esters of amino alcohols, in JP-A-50-99529 As a fluorescent whitening agent, such as the fluorine-containing surfactant,
Compounds described or exemplified in No. 45-24068, JP-A No. 54-94318, etc. can be included. In carrying out the present invention, the apparatus for applying the back coat coating liquid onto the surface of the hydrophobic support opposite to the surface on which the silver halide photographic constituent layers are provided include an air knife coater, a roll coater, a bar coater, a blade coater, and a slide coater. Examples include hopper coaters, gravure coaters, flexogravure coaters, and combinations thereof. Prior to coating, it is desirable to activate the surface of the hydrophobic support by corona treatment, flame treatment, or the like. Various drying devices are used to dry the applied coating liquid, including hot air dryers such as straight tunnel dryers, arch dryers, air loop dryers, and sine curve air float dryers, and dryers that use infrared rays, heated dryers, microwaves, etc. can be given. The silver halide photographic emulsion layer according to the present invention includes various types. Examples include a photographic emulsion layer for enlarged positives, a photographic emulsion layer for contact positives, a photographic emulsion layer for negatives, a color photographic emulsion layer, a photographic emulsion layer for printing, a photographic emulsion layer for direct positives, a photographic emulsion layer for diffusion transfer method, etc. . In addition, such photographic emulsion layers contain binders such as gelatin and gelatin derivatives, chemical sensitizers such as hypo, noble metal sensitizers such as gold salts and platinum salts, hexahalogenorhodium () complexes, and hexahalogenorhodium () complexes. High contrast agents such as nucleic acid decomposition products, JP-A-50-147925,
Crystal habit modifiers for silver halide grains such as mercapto heterocyclic compounds described or exemplified in No. 51-107129, colors cited or exemplified in the specifications of JP-A-52-65432 and JP-A-52-88340. Sensitizers, stabilizers, antifoggants, color photographic couplers, hardeners, dihydroxybenzene compounds, coating aids, fogging agents, additives for direct positive photographic emulsions such as direct positive photographic dyes, and dye developers. , and other additives. The silver halide photographic material according to the present invention can be used for exposure, development, etc. as described in "Photographic Light-sensitive Materials and Handling Methods" (Kyoritsu Shuppan, written by Goro Miyamoto, Photographic Technology Course 2), depending on the photographic material. stop, fix, bleach,
Multi-layer silver halide color photographic materials, which undergo one-bath bleach-fixing treatment after color development, are treated with stabilizers, CD-, CD- (the above two compounds are trade names of Kodatsu Co., Ltd.), droxychrome ( It can be processed with any color developer such as May & Baker Co., Ltd. (trade name). Benzyl alcohol, thallium salt, phenidone, etc. may be added to the developer solution containing such a main agent. Also,
Useful one-bath bleach-fix solutions include metal salts of aminopolycarboxylic acids (e.g., ferric complex salts such as ethylenediaminetetraacetic acid, propylenediaminetetraacetic acid, etc.)
It is a solution, and the fixing agent is sodium thiosulfate,
Ammonium thiosulfate and the like are useful. Such a one-bath bleach-fix solution may contain various additives. For example, desilvering accelerators (e.g. mercaptocarboxylic acids as described in U.S. Pat. No. 3,512,979, mercapto-heterocyclic compounds as described in Belgian Patent No. 682,426, etc.), antifouling agents, PH regulators or PH buffers, dura mater agents (e.g. magnesium sulfate, aluminum sulfate, potash alum, etc.),
Various compounds such as surfactants can be contained in combination. Also, although such single bath bleach-fix solutions can be used at various PHs, the useful PH range is
PH6.0-8.0. Next, in order to explain the present invention more specifically,
An example will be described. Example 1 Paper with a basis weight of 160 g/m ² was run at 80 m/min, and after corona discharge treatment on the back side in the first zone, low density polyethylene (density 0.918, MI5) was processed using a melt extruder.
50 parts, high density polyethylene (density 0.965, MI7)
A resin composition consisting of 50 parts was applied by melt extrusion to a resin thickness of 30 μm to form a resin layer with a matte surface. After corona discharge treatment on the cover surface in the second zone, low density polyethylene (density 0.918, MI8.5) was manufactured using a melt extruder.
30 parts of master batch mixed with 30% by weight of titanium oxide, low density polyethylene (density
0.918, MI5.0) 45 parts, high density polyethylene (density
0.965, MI7.0) 25 parts resin thickness
A resin layer with a glossy surface is formed by melt extrusion coating at a thickness of 30 μm. In the third zone, after corona discharge treatment is applied to the back resin surface, a rotating 140-mesh gravure roll is immersed in the coating liquid listed in Table 1, the excess coating liquid is scraped off with a blade, and the coating liquid is kept constant. A photographic support with antistatic properties was produced by transferring the mixture onto a surface and drying it. The amount of water-based coating liquid applied is 3g/m ²
(moisture).

【table】

[Evaluation of antistatic performance of back coat layer]

The surface resistivity of the sample was measured at 20° C. and 35% RH for the sample before color development and the sample after color development using a roll processor using the following processing method. Color development (30℃, 3 minutes 30 seconds) → Bleach fixing (30
℃, 1 minute 30 seconds) → 30℃, 3 minutes) → Drying (45℃, 1
(minute) [Evaluation of film strength of back coat layer] After immersing in color developer for 3 minutes at 20℃, the sphere diameter was 1 mm.
The ball point needle is set perpendicular to the film surface of the back coat layer, and the load of the ball point needle that causes damage to the back coat film (hereinafter referred to as film strength) is calculated when the sample surface is moved in parallel at a speed of 2 cm/sec. Measure. [Evaluation of pencil retouchability of back coat layer] Write with an HB pencil, observe the recording state on the surface, and judge effectiveness. [Evaluation of haze on the surface of photographic paper] Cut the sample to a size of 8.25 cm x 8.25 cm, and stack 10 sheets so that the back coat layer and the silver halide photographic constituent layer are in contact with each other. This is placed in an environment of 40℃ and 80%RH, and a load of 4.5Kg is applied to it for 24 hours. After that, take it out, peel off the sample,
Visually judge the degree of cloudiness on the surface of the photographic paper. [Evaluation of type printability of back coat layer] Using an impact printer installed in an automatic printer, a type ribbon (for Kodatsu Back Printer manufactured by Eastman Kodak Co., Ltd.) was interposed between the back coat layer surface of the sample and the type. Then, information consisting of numbers, letters, lines, etc. was printed in the form of type on the surface of the back coat layer. After type printing 1
At the 1st, 50th, and 3rd hour, samples with type imprints are processed with a roll processor, and the state of disappearance of the type imprints is observed and judged. The results obtained are shown in Table 2.

[Table] As can be seen from Table 2, the sample that does not contain latex (No. A) specified in Table 1 (Note 2) and the sample that does not have colloidal silica (No. B) are different from the other samples (No. It can be seen that the antistatic performance is insufficient compared to No. .C to No.M). Furthermore, even within the present invention, it can be seen that the greater the amount of colloidal silica and the greater the amount of latex defined in (Note 2), the better the antistatic performance. The sample with the largest amount of colloidal silica (No. F) showed a slight deterioration in film strength and type printability, indicating that it is unsuitable when such performance is particularly important. Although it is unclear from Table 2, coating streaks occurred during coating in the sample (No. H) with the largest amount of latex specified in (Note 2). Therefore, it may not be suitable for those who do not have advanced coating technology. Sample (No.I~
M) indicates that the addition of a matting agent imparts pencil addition performance. Samples (Nos. K to M) show that the film strength is strengthened by adding a compound having two or more ethyleneimino groups or two or more epoxy groups in the molecule. Sample (No. M) shows that the film strength can be enhanced even by using different types of latex together. Example 2 Instead of the coating liquid listed in Table 1 of Example 1, the third
The same procedure as in Example 1 was conducted except that the coating liquid listed in the table was used. The results obtained are shown in Table 4.

【table】

[Table] As shown in Table 4, samples outside the present invention (No.N,
O) tends to cause clouding on the front side of the photographic paper when attempting to obtain pencil retouchability equivalent to that of the present invention. On the other hand, the samples of the present invention (Nos. P and Q) achieve sufficient pencil retouchability with a small amount of inorganic pigment, so that no clouding occurs on the front side of the photographic paper. In the present invention, a sample (No.
Q) shows some improvement in antistatic performance and film strength, but shows deterioration in type printing. It can be seen that the combined use of such water-soluble polymers may be disadvantageous depending on the application. Example 3 Instead of the coating liquid listed in Table 1 of Example 1, Coating liquid No. 5 was used.
The same procedure as in Example 1 was conducted except that the coating liquid listed in the table was used. The results are shown in Table 6.

【table】

[Table] When the sample using formalin (No. R) was developed immediately after preparation, fogging was observed. Further, when observed after storage at 35°C for one month, discoloration of the cyan, magenta, and yellow layers was observed, with the magenta layer in particular showing significant discoloration. Contamination was also observed on the back side. The sample using glyoxal (No.S) is still
Contamination was observed on the back side when observed after storage at 35°C for one month. From Table 6, samples using gelatin (No.R, S,
It can be seen that the film strength of sample T) is improved compared to the sample (No. U) in which none of the samples was used. However, the use of formalin glyoxal as a curing agent is not suitable for the purpose of the present invention for the reasons mentioned above. Example 4 Hardening agent NER-010 in the formulation of sample No. T of Example 3
Instead of N,N'-ethylenebis(vinylsulfonylacetamide), 1,3,5-triacryloyl-hexahydro-S-triazine, 2,4-
The same procedure as in Example 3 was carried out except that dichloro-6-hydroxy-S-triazine sodium salt and 1,6-hexamethylene diisocyanate were used, respectively. As a result, exactly the same results as in Example 3 were obtained.

Claims (1)

[Scope of Claims] 1. A resin-coated paper type photographic support in which both sides of a base paper are coated with a resin has a silver halide photographic constituent layer on one side, and at least a silver halide photographic constituent layer on the opposite side of the support.
In a silver halide photographic material having a back coat layer containing (a) a polymer latex and (b) colloidal silica, the polymer latex contains (a) 1.0 to 5.0% by weight of acrylic acid based on the total monomers. or obtained by copolymerization of methacrylic acid, (b) 5.0 to 20% by weight of styrene sulfonic acid, the remaining weight% of (c) acrylic acid lower alkyl ester, and (d) styrene, and (c) Weight composition of acrylic acid lower alkyl ester to (di)styrene is 1.0 to 1.0 to 2.0
1. A silver halide photographic material characterized in that it is an emulsion of a copolymer or an acid-neutralized product thereof. 2 The content of the polymer latex is 1.0 mg/m ² to 300 mg/m ² as a polymer content, and the content of the colloidal silica is 10 mg/m ² as a solid content.
The silver halide photographic material according to claim 1, wherein the silver halide photographic material has a silver halide content of from 1.0 g/m ² to 1.0 g/m 2 . 3. The silver halide photographic material according to claim 1 or 2, wherein the back coat layer contains (c) a matting agent. 4 The content of the matting agent is 5 mg/m ² to 500
The silver halide photographic material according to claim 3, which is mg/m ² . 5. Claims 1, 2, 3, or 4, wherein the back coat layer contains (d) a compound having two or more ethyleneimino groups or glycidyl ether groups in the molecule. The silver halide photographic material described in Section 1. 6 The content of the compound having two or more ethyleneimino groups or glycidyl ether groups in the molecule is relative to the polymer content of the polymer latex.
A silver halide photographic material according to claim 5, wherein the silver halide photographic material is 2.0% to 50% by weight. 7. The halogenated material according to claim 1, 2, 3, or 4, wherein the back coat layer contains (e) gelatin and (f) a non-formalin-based gelatin hardening agent. silver photographic material.