JPS5815780B2 - Polyester Film Polyester Film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a subbing layer of a polyester film for photographic materials using a mixture of polymers or copolymers.
More specifically, when forming a composite by coating a hydrophilic composition such as a silver halide emulsion, a silk composition for preventing halation of silver halide photographic light-sensitive materials, or a composition for preventing curl on a polyester film, the polyester The present invention relates to a subbing layer for a polyester film for photographic materials, which can provide excellent adhesion between the film and a hydrophilic layer and has particularly good scratch resistance.

Generally, when laminating a photographic light-sensitive layer on a support film of a photographic light-sensitive material, in order to ensure adhesion between the photographic light-sensitive layer and the support film, it is necessary to provide a subbing layer as an intermediate layer that has an affinity for these layers. .

Recently, polyester films with excellent physical properties have been used as supports for photographic materials in place of conventional cellulose films.

However, the polyester film is extremely hydrophobic compared to conventionally used films, so when a hydrophilic layer such as a photographic light-sensitive layer is laminated on such a support, adhesion and other photographic properties cannot be satisfied. Finding a suitable sublayer is technically an extremely difficult problem.

In particular, when laminating a silver halide photosensitive layer, excellent adhesion is always required under all photographic processing conditions, and it is necessary to satisfy blocking resistance and scratch resistance of the outer subbing layer. This has been raised as an important technical problem by those skilled in the art, and methods using various subbing layers have been attempted.

For example, a vinylidene terpolymer containing an acid component having an affinity for the support film and the photographic light-sensitive layer, a polymer obtained by grafting a copolymer of butyl acrylate and styrene onto gelatin, or a butadiene-based polymer, such as ethylene chloride, dioxane, etc. It is dissolved in an organic solvent such as acetone or methyl alcohol, and an organic solvent such as chlorphenol or cresol, which is a solvent or swelling agent for the support film, is added to strengthen the adhesion between the support film and the photographic light-sensitive layer. A method of forming an undercoat layer using the prepared undercoat composition has been carried out.

However, in all methods of forming an undercoat layer using such a solvent-based undercoat composition, when the undercoat composition is applied and dried, organic solvent vapors harmful to the environment are emitted, and
It often interferes with work.

For this reason, it is necessary to invest a large amount of money in installing a recovery device.

Furthermore, the inclusion of the solvent or swelling agent for the support film in the composition cited below not only releases harmful vapors, but also causes the film to lose its transparency and impairs the finish quality, such as impairing the flatness of the film. The negative effects of significant deterioration often occur.

Therefore, for example, a method is used in which an undercoat layer is formed using a solvent-based undercoating composition that does not contain a solvent or a swelling agent for the support film before stretching the support film, or after stretching the support film uniaxially and before stretching the support film biaxially. However, this method also has problems in production, such as stretching after underdrawing, which makes it impossible to recover the peripheral portion of the film, resulting in a large amount of loss.

As an undercoat method that improves these drawbacks, a method has been adopted in which an undercoat layer is formed using an aqueous copolymer dispersion of various monomers.

For example, in U.S. Pat. No. 3,615,556, butadiene containing an acid component is added to a biaxially stretched polyester film.
A method of forming a subbing layer using an aqueous dispersion containing a styrene copolymer has been described, e.g., US Pat. No. 2,627
No. 088 and U.S. Pat. No. 2,698,240 describe a method of forming an undercoat layer on a polyester film before stretching using an aqueous dispersion containing a vinylidene copolymer containing an acid component. Special Publication No. 44-13278 and Special Publication No. 45-1
No. 0988 discloses that a biaxially stretched polyester film is coated with an undercoat layer using an aqueous dispersion containing a copolymer of an alkyl acrylate and an aliphatic bifunctional monomer having two allyl or vinyl groups. A method for forming the composition has been described, and attempts have been made to eliminate the disadvantages that occur when using the solvent-based compositions cited below.

On the other hand, among the polyester films, particularly hydrophobic 2
When using a support such as an axially stretched polyethylene terephthalate film, a method is adopted in which the surface of the support is previously subjected to a hydrophilic treatment such as corona discharge or ultraviolet irradiation. By using this method in combination with the method of forming an undercoat layer, it has become possible to obtain extremely excellent adhesion.

However, when forming an undercoat layer on a polyester film using an aqueous dispersion of the copolymer as described above, contact between the films by the transport roll or during winding may occur, and furthermore, photosensitive There is a need for an undercoat layer for polyester films for photographic materials that can prevent scratches that tend to occur due to contact with conveyor rolls during the manufacturing process for laminating layers.

However, the reality is that a subbing layer for polyester films for photographic materials that is sufficiently satisfactory for practical use has not yet been found.

The object of the present invention is to produce a photographic light-sensitive material using a polyester film as a support, without emitting harmful organic solvent vapor, and having excellent adhesion properties, as well as in the undercoating process and photographic material. A polyester film for photographic light-sensitive materials that does not cause scratch failures due to mechanical friction of winding rolls, transport rolls, etc. or contact between films during the manufacturing process of laminating photosensitive layers, especially silver halide emulsion layers. The goal is to provide an underlying layer for

The present inventors added a copolymer of diolefin and a vinyl monomer and a polymer or copolymer reactive with the copolymer and/or gelatin in the subbing layer of a polyester film for photographic light-sensitive materials. It has been found that the above object can be achieved by containing the above-mentioned components.

That is, the polyester film undercoat layer for photographic light-sensitive materials of the present invention contains a diolefin copolymer as a component of the mixture, which has the property of absorbing mechanical shock and inherently reducing the occurrence of scratches. system copolymer,
Gelatin that may be mixed in the subbing liquid, gelatin in a gelatin layer (second subbing layer) that may be provided on the subbing layer, and photographic light-sensitive layer containing gelatin provided on the subbing layer, for example, a silver halide emulsion. Because the mixture contains a copolymer with a reactive group that reacts with gelatin, etc. in the layer, it not only has excellent adhesion between the support film and the photographic light-sensitive layer, especially the silver halide emulsion layer. It has particularly excellent scratch resistance.

Therefore, the undercoat layer of the polyester film for photographic light-sensitive materials of the present invention does not cause scratches due to mechanical impact, friction, friction between support films, etc. during the process of producing silver halide photographic materials, and therefore silver halide Poor adhesion due to the scratches mentioned above when developing photographic materials;
No black streaks, white streaks, or other serious failures in photographic performance occur.

Examples of the polyester film used in the present invention include polyethylene terephthalate film, polyethylene-2,6-naphthalate film, poly-(cyclohexane-1,4-dimetatool)-terephthalate film, etc., but preferably biaxial A stretched polyethylene terephthalate film is used.

The mixing ratio of the polymer or copolymer mixture contained in the below-mentioned composition used in the present invention is preferably 50 to 95% in terms of solid content of the copolymer of diolefin and vinyl monomer.
Parts by weight of the polymer or copolymer having a reactive group are 5 to 5
It is 0 parts by weight.

Further, the proportion of the constituent components of the copolymer of diolefin and vinyl monomer used in the present invention is (a) diolefin 20 to
70 parts by weight, as the vinyl monomer, (b) 0.5 to 20 parts by weight of ethylenically unsaturated acid and the remainder (C) the above (
Ethylenically unsaturated monomers that can be copolymerized with a) or Cb) are preferred.

The molecular weight of the diolefin copolymer used in the present invention having such components is preferably 5000 to 500.
The range is 000.

Examples of the diolefin (a) which is a constituent component of the copolymer of diolefin and vinyl monomer used in the present invention include butadiene, isoprene, neoprene, and chloroprene.

(b) Ethylenically unsaturated acids include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, mesaconic acid, and citraconic acid.

(C) Ethylenically unsaturated monomers that can be copolymerized with these include methyl acrylate, methyl methacrylate,
Ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, chloroethyl acrylate, chloroethyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, 2-ethylhexyl acrylate, glycidyl acrylate, glycidyl methacrylate, phenyl acrylate, phenyl methacrylate , benzyl acrylate, benzyl methacrylate, phenylethyl acrylate, phenylethyl methacrylate, chloromethyl acrylate,
Chloromethyl methacrylate, 4-chlorobutyl acrylate, 4-chlorobutyl methacrylate, N-N-diethylaminoethyl acrylate, N-N-diethylaminoethyl methacrylate, sulfopropyl methacrylate, 2-ethoxyethyl acrylate, 2-ethoxyethyl methacrylate, acrylamide, Methacrylamide, N-alkylacrylamide (alkyl groups include methyl, ethyl, propyl, butyl, amyl, hexyl, etc.), N-N-dialkylacrylamide (alkyl groups include those listed above, but dialkyl is different) It may also be an alkyl group.

), N-phenylacrylamide, N-benzylacrylamide, N-phenylethylacrylamide, N-oxycarbonylmethylacrylamide, N-oxycarbonylethyl acrylamide, N-oxycarbonylphenyl acrylamide, acrylonitrile, methacrylideryl, α-chloroacrylonitrile, Alkyl-α
-chloroacrylate (methyl group as alkyl group,
ethyl group, propyl group, butyl group, benzyl group, cyclohexyl group, etc.), alkyl-α-chloromethacrylate (the alkyl group is the same as above), acrolein, methacrolein, vinyl isocyanate, isopropylisocyanate, styrene, α- methylstyrene,
p-chloromethylstyrene, m-chloromethylstyrene, o-chloromethylstyrene, vinyl methyl ether,
Examples include vinyl ethyl ether, vinyl acetate, butyl propionate, vinyl chloroacetate, vinyl trichloroacetate, vinyl chloride, and vinylidene chloride.

Note that the glass transition temperature of the copolymer is preferably -30°C to 30°C.

The copolymer of diolefin and vinyl monomer used in the present invention is preferably an aqueous copolymer dispersion, particularly an aqueous copolymer dispersion containing butadiene as a constituent component as the diolefin.

Such a copolymer latex containing butadiene as a constituent component is commercially available and can be easily obtained.

For example, (A) Nirapol LX-416 (manufactured by Nippon Zeon) styrene-butadiene copolymer latex (copolymerization ratio: styrene-butadiene - 60:40 (wt%)) (B) Crossrene NA-10 (manufactured by Takeda Pharmaceutical Co., Ltd.) Styrene-butadiene copolymer latex (copolymerization ratio styrene:butadiene-60:40 (wt%) (C) SN-304 (manufactured by Sumitomo Naugac) Styrene-
Butadiene copolymer latex (copolymerization ratio is styrene:
Butadiene-6o: 40 (wt%) etc. are preferably used in the present invention.
X411, LX415, LX420. LX430゜LX
2570X5 (manufactured by Zeon Corporation) Crossren 5A
-20, 2M-30, 2M33A (manufactured by Takeda Pharmaceutical Co., Ltd.)
N-2752E (manufactured by Sumitomo Naugatuck) etc. can also be used in the same manner.

Next, the reactive polymer or copolymer used in the present invention is a copolymer consisting of the diolefin and a vinyl monomer, a homopolymer of a monomer having a group reactive with gelatin, or other polymers. It is a copolymer with a monomer, and its molecular weight is preferably in the range of 5,000 to 500,000.

Typical examples of monomers having reactive groups that are constituent components of the reactive polymer or copolymer used in the present invention include glycidyl acrylate, glycidyl methacrylate, acuberolein, and N-methylolacrylamide. , N-(ethyleneiminoalkyl)-
Examples include acrylamide, N-(ethyleneiminoalkyl)-methacrylamide (wherein the alkyl group is a positive integer having 1 to 4 carbon atoms), 2-hydroxyethyl methacrylate, maleic anhydride, or itaconic anhydride, and the like. As the monomer copolymerizable with the group-containing monomer, all those exemplified as the monomer copolymerizable with the diolefin can be used.

The preferable proportion of the monomer having a reactive group in the copolymer varies depending on the type of monomer having a reactive group in relation to adhesive properties.

For example, when the monomer having a reactive group is acrolein, the preferable proportion for adhesion in the copolymer is 2 to 50% by weight, glycidyl acrylate or glycidyl methacrylate is 25 to 60% by weight, N=( 2-70% by weight of (ethyleneiminoalkyl)acrylamide and 5-50% by weight of maleic anhydride.

As described above, the proportion of the reactive group-containing monomer in the copolymer varies depending on the type of monomer, but it is generally preferably in the range of 100 to 1% by weight.

Next, typical copolymers having the above-mentioned reactive groups include (I) ethyl acrylate-acrolein copolymer (copolymerization ratio, 70:30% by weight) (■) methyl methacrylate-butyl acrylate- N
-Methylol acrylamide copolymer (copolymerization ratio, 50
:40:10% by weight) (■) Butyl methacrylate-styrene-2-hydroxyethyl acrylate copolymer (copolymerization ratio.

60:30:10% by weight) (IV) Ethyl acrylate-glycidyl methacrylate copolymer (copolymerization ratio, 50:50% by weight)■ Ethyl acrylate-vinylidene chloride-glycidyl methacrylate copolymer (copolymerization ratio, 50:10 :40
% by weight).

The polymer or copolymer having the monomer having a reactive group as a constituent component is mixed with an aqueous dispersion of the copolymer of the diolefin and vinyl monomer as an aqueous dispersion and used for subbing. It will be done.

In order to produce an aqueous dispersion of the copolymer having the above-mentioned reactive group by emulsion polymerization, for example, a compound selected from among the monomers exemplified as monomers copolymerizable with the above-mentioned diolefin is added to degassed distilled water. and a monomer having a reactive group in an amount of about 10 to 50% by weight of the total,
Add an appropriate amount of mainly an anionic surfactant and a water-soluble polymerization initiator, such as potassium persulfate, while stirring.
An aqueous dispersion of the reactive copolymer can be produced by emulsion polymerization under heating at ~90°C for several hours.

As described above, the diolefin copolymer and the polymer or copolymer having a reactive group used in the present invention include 50 to 95 parts by weight of the diolefin copolymer and a polymer or copolymer having a reactive group. When the mixture is mixed in a proportion of 5 to 50 parts by weight and used to form a subbing layer of a polyester film, it is possible to achieve the effect of ensuring excellent adhesion and scratch resistance.

The composition cited below using such a mixture may be solvent-based, but is preferably an aqueous dispersion of the copolymer mixture, which may also contain gelatin or other water-soluble polymer compounds. .

The aqueous dispersion used in the present invention is one in which polymer (including copolymers) particles are dispersed in water or an aqueous dispersion medium (for example, a mixture of water and methanol).

The aqueous dispersion may contain a surfactant, which may include residual surfactant used during emulsion polymerization,
Alternatively, it may be added separately to improve the dispersibility of the polymer particles, and preferably an anionic surfactant is used as the surfactant, such as sodium lauryl sulfate, which has 8 to 18 carbon atoms. Alkali metal salts or ammonium salts of alcohols: ethanolamine lauryl sulfate, ethylamine lauryl sulfate: alkali metal salts and ammonium salts of sulfonated petroleum or paraffin oils, such as nidodecane-1-sulfonic acid, octadiene-1-sulfonic acid, etc. Alkali metal salts of aromatic sulfonic acids: alkali metal salts of alkyl sulfates such as isoglobilbenzene sulfate sodium salt and imbutylnaphthalene sulfate sodium salt; sulfones such as dioctylsulfosuccinate sodium salt and dioctadecylsulfosuccinate disodium salt; Examples include alkali metal salts or ammonium salts of dicarboxylic acid esters.

The undercoat composition for forming the undercoat layer for photographic light-sensitive materials of the present invention can contain various additives.

For example, anionic surfactants such as those mentioned above; nonionic or cationic surfactants; matting agents such as silica particles and polymer matte particles; dyes or pigments for antihalation or coloring; antistatic compounds; gelatin, etc. Binder: A suitable hardening agent, such as a compound having an aldehyde group such as formaldehyde or glyogyzal,
Compounds with ethyleneimino groups such as mucochloric acid, tetramethylene-1,4-bis (ethylene urea), hexamethylene-1,6-bis (ethylene urea), methanesulfonic acid esters such as trimethylene bismethane sulfonic acid ester , bisacryloylurea, active vinyl compounds such as metaxylene divinyl sulfone, 2-methoxy-
Additives such as a compound having an active halogen such as 4,6-dichlorotriazine, a compound having an epoxy group such as bisphenol glycidyl ether, incyanate, etc. can be contained.

Furthermore, the composition cited below has a dry film breakage of approximately 0.05 to 5 g/m of the undercoat layer obtained by coating it on the surface of a polyester film.
It is set so that it becomes 2.

As the coating method used at this time, conventional coating methods for the compositions cited below can be used, such as dip coating, roll coating, spray coating, and the like.

In addition, the polyester film can be subjected to an appropriate pretreatment before the composition cited below is applied to the polyester film. For example, preferably, the polyester film is subjected to a so-called corona discharge treatment, and then the composition cited below is By applying the material and drying it, you can achieve even better undercoating effect (
For example, stronger adhesion between a hydrophilic photosensitive layer and a support)
can be obtained.

In addition to the above-mentioned corona discharge treatment, for example, ultraviolet irradiation treatment, flame treatment, etc. can be used.

Corona discharge treatment is a device that accelerates and releases electrons between a pair of electrodes in the presence of gas or under vacuum. Other similar electron impact treatments are also effectively used, and ultraviolet irradiation treatment is This is generally done by mercury lamp irradiation,
A low-pressure, medium-pressure or high-pressure mercury lamp can be used, but preferably a low-pressure mercury lamp provides a better bond.

Further, the flame treatment is to treat the surface of the support with an oxidizing flame, and any flame that generates an oxidizing flame may be used.

When such discharge, ultraviolet or flame treatment is performed, it is desirable that the contact angle of the hydrophobic surface with water is 58° C. or less.

The polyester film having a subbing layer of the present invention may be coated with a gelatin or other hydrophilic polymer layer (for example, Japanese Patent Publication No. 46-24159) on the support before providing a hydrophilic layer, especially a photosensitive layer, as required. Public notice.

Japanese Patent Publication No. 48-91165, Special Publication Box 49-23
(described in Japanese Patent No. 828) may be used.

Further, after forming the subbing layer of the present invention on a polyester film, heat treatment can be performed at 100 to 180°C as required. After forming, the same temperature ranges from 100℃ to 180℃.
It can be heat treated at ℃.

Example 1 A biaxially stretched polyethylene terephthalate film with a thickness of 180 μm was transported using a HF5G-2 type corona discharge device manufactured by Rebel Co., Ltd., and the film transport speed was 20 rr per minute, L1, and electrode gap 1.
．． The discharge treatment was carried out under the conditions of 6 cages, 350 watts of power, and 12 amveyor current.

Next, Exemplary Compounds A and B were used as the diolefin copolymer aqueous dispersion according to the present invention, and ■, ■, and ■ were used as the reactive copolymer aqueous dispersion, and the mixture ratios were as shown in Table 1. The aqueous dispersion shown below was prepared by diluting with water so that the solid content concentration was 3.0% by weight.

Next, each of the aqueous dispersions was coated on the surface of the corona discharge-treated polyethylene terephthalate film using a double roll coater and dried at 100°C for 3 minutes to form a dry coating of 0.5 to 0.6 g/m2 (sample). No1.2
and 3) were created.

Exemplary compound ■ as an aqueous dispersion of a reactive copolymer without separately mixing an aqueous diolefin copolymer dispersion;
Comparative sample (
Sample plates 4.5 and 6) were created.

These samples and comparative samples were subjected to a scratch test using the method described below, and the results are shown in Table 1.

Scratch Test Method A sapphire needle with a tip radius of 0.5 mm is placed on the sample surface, a weight is placed on top of the needle, and the sample stage holding the sample under pressure is moved at a constant speed of 45 cm per minute.

The scratch resistance performance is indicated by the weight of the weight at which the presence of scratches caused by the sapphire needle on the sample surface can be clearly recognized when the weight of the weight is changed.

It has been shown that the larger the weight of the weight at this time, the less likely it is that scratches will occur on the sample, and that if it is 300 g or more, there will be no practical problem.

From Table 1, the following composition using a mixture of an aqueous dispersion of a diolefin copolymer of the present invention and an aqueous dispersion of a copolymer having a reactive group is coated on a polyethylene terephthalate film. It can be seen that the resulting undercoat layer has much better scratch resistance than the comparative undercoat layer using only an aqueous dispersion of a copolymer having a reactive group.

Example 2 A 0.5% by weight aqueous gelatin solution was applied to the sample used in Example 1 and the surface of the sample using a double roll coater,
Samples dried at 100°C for 3 minutes and further heat treated at 130°C for 5 minutes to give a dry film of 0.1 g/m2, and Japanese Patent Publication No. 46-24159, Japanese Patent Publication No. 48-91165, and Japanese Patent Publication No. 49-23828. Silver iodobromide was coated on the undercoat layer of each sample in which a 0.5% by weight aqueous solution of a water-soluble polymer compound synthesized by the method of Synthesis Example 1 was coated in the same manner as the gelatin aqueous solution. The adhesion performance was measured by the following methods (a), (b), and (4) after coating the containing X-ray silver halide emulsion. (b) Dry film test before development processing, (b) During development processing. The results of the wet film test ((c)) and the film test after development and drying (c) both showed values of 80% or more, indicating that the undercoat layer of the present invention is sufficiently satisfactory for practical use.

(a) Make scratches with a razor blade on the silver halide emulsion surface of the test sample with a dry film before treatment in the shape of a substrate so that they reach the film support, press the cellophane adhesive tape on top of the scratches, and then The ratio of the remaining emulsion film to the adhesive area of the cellophane tape when it is suddenly peeled off is expressed as a percentage.

(b) Wet film formation test during development processing.During development processing, while still wet, scratches are made on the surface of the silver halide emulsion using a metal needle with a drilled tip, and the surface is rubbed to ensure that no emulsion film remains. The percentage is expressed as a percentage.

Dried film test after processing The film test was performed on the finished product after development, fixing, washing with water, and drying using method (a), and the remaining proportion of the emulsion film is expressed in %.

Example 3 The surface of a biaxially stretched polyethylene terephthalate film having a thickness of 100 microns was subjected to corona discharge treatment in the same manner as in Example 1.

Next, as an aqueous dispersion of a diolefin copolymer according to the present invention, Exemplary Compound B and Aqueous Dispersion of a Copolymer Having a C1 Reactive Group Exemplary Compounds (1), (2), and (2) were used in a mixing ratio as shown in Table 2. Dilute with water to make the solid content concentration 50% by weight, and further add 1.5% by weight of saponin and 40% by weight of trimethylene dimethane sulfonate based on the solid content.
The following aqueous dispersion was prepared by adding silica powder having a particle size of 3 to 5 μm to a concentration of 0.01% by weight.

Next, each of the aqueous dispersions was coated on the surface of the corona discharge-treated polyethylene terephthalate film using a double roll coater, and dried at 100°C for 3 minutes to give a dry coating of about 1.0°C. /m samples (sample Nos. 7.8 and 9) were prepared.

Exemplary compound ■ is used as a copolymer aqueous dispersion having a reactive group without separately mixing an aqueous diolefin copolymer dispersion.
Comparative samples (Sample Nos. 10.11 and 12) were prepared in the same manner as the samples except that only , ■, and ■ were used.

These samples and comparative samples were subjected to a scratch test in the same manner as in Example 1, and the results are shown in Table 2.

Table 2 shows that the mixture of the diolefin copolymer aqueous dispersion of the present invention and the copolymer aqueous dispersion having a reactive group is further added with saponin, hexamethylene-bis(N-N-ethyleneurea) and silica. The undercoat layer obtained by coating the undercoat composition obtained by mixing the powders on the polyethylene terephthalate film has extremely superior scratch resistance performance compared to the comparative undercoat layer excluding the diolefin copolymer aqueous dispersion. I understand what is shown.

Example 4 A 1.0% by weight gelatin aqueous solution was coated on the surfaces of the samples used in Example 3 (sample Nos. 7.8 and 9) using a double roll coater, and dried at 100° C. for 3 minutes.

The dry film thickness at this time was approximately 0.2/m2.

Next, a silver halide emulsion for squirrels containing silver chlorobromide was applied on top of this, and the adhesion performance was measured in the same manner as in Example 1. The results of the dry film test before and after the development process were The adhesiveness of the undercoat layer of the present invention was found to be 80% or more, and the wet film adhesion test result during development was 100%, indicating that the undercoat layer of the present invention has adhesion that is sufficiently satisfactory for practical use.

Claims (1)

[Claims] 1 (3) 20-70% by weight diolefin and 80-70% by weight
Copolymer with 30% by weight of vinyl monomer and (B) glycidyl acrylate, glycidyl methacrylate, acrolein, N-methylolacrylamide, N-(ethyleneiminoalkyl)acrylamide, N-(ethyleneiminoalkyl)methacrylamide, 2 - A polymer or copolymer having as a constituent component at least one member selected from the group consisting of hydroxyethyl methacrylate, maleic anhydride, and itaconic anhydride (A): (
1. A polyester film for photographic materials having a subbing layer comprising a layer coated with an aqueous dispersion containing B) in a ratio of 50 to 95:5 to 50 (weight ratio).