JPH08134245A - Antistatic film - Google Patents

Abstract

PURPOSE: To obtain an antistatic film which has an antistatic coating layer excellent in antistatic properties by coating a polyester film with a water-base coating soln. contg. a compsn. prepd. by compounding specified amts. of specific compds. CONSTITUTION: At least one side of a polyester film is coated with a water-base coating soln. contg. a compsn. contg. 1-40wt.% phosphoric ester salt and dried. The film is then stretched to give an antistatic film having an antistatic coating layer. The salt is a compd. having a phosphoric ester salt group in the molecule. The coating layer is pref. formed from a compsn. comprising the salt (A), a binder resin (B) selected from among a polyester resin, an acrylic resin, and an acryl-modified polyester resin, and a surfactant (C) in a amts. satisfying the relations: [A[+[B-]+[C]=100wt.% and 0.01<=[A]/-([A]+[B)]<=0.50 and is pref. 0.005-3μm thick.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an antistatic film,
More specifically, magnetic recording materials such as magnetic cards (for example, telephone cards and prepaid cards), magnetic tapes (for example, audio tapes and video tapes), magnetic disks (for example, floppy disks), electronic materials, and graphic materials having excellent antistatic properties. , An antistatic film useful as a plate-making film, an OHP film and the like.

[0002]

Films made of polyester such as polyethylene terephthalate and polyethylene naphthalate are widely used for magnetic recording materials such as magnetic cards and magnetic tapes, and for general industrial materials such as packaging materials, photographic materials and graphic materials. ing. However, such a polyester film has a drawback that it has a large surface resistivity and is easily charged by friction or the like. When the film is charged, dust or dirt is attached to the surface of the film, which causes troubles. In addition, electric discharge occurs in the processing step, and there is a risk of ignition if an organic solvent is used.

As one of the methods for preventing such troubles due to charging, various methods for forming an antistatic coating film on the film surface have been proposed and put into practical use. As the antistatic agent to be contained in the antistatic coating film, a low molecular weight type and a high molecular weight type are known, but each has its own advantages and disadvantages. Therefore, the antistatic agent is used properly according to its characteristics.

For example, as a low molecular type antistatic agent, a long-chain alkyl compound having a sulfonate group (Japanese Patent Laid-Open No. 4-
No. 28728) and the like, and surfactant type anionic antistatic agents are known, and as a polymer type antistatic agent, a polymer having an ionized nitrogen element in its main chain (Japanese Patent Application Laid-Open No. 3-301). 255139, JP-A-4-28812.
No. 7, JP-A-6-172562), polystyrene sulfonate (JP-A-5-320390) and the like are known.

However, in an antistatic coating film using such a low molecular type antistatic agent, the antistatic agent moves in the coating film, accumulates at the interface, and migrates to the opposite surface of the film (hereinafter There is a problem of "back surface transferability") and a problem of deterioration of antistatic property (hereinafter sometimes referred to as "antistatic property") over time. On the other hand, in the case of antistatic coatings that use high-molecular type antistatic agents, in order to improve antistatic properties, a large amount of antistatic agents must be blended and thick antistatic coatings should be used. Since it is necessary to form it, it is not economical, and there is a problem that the antistatic property deteriorates under low humidity conditions.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide an antistatic film which solves the problems of the prior art.

[0007]

In order to achieve such an object, the present invention has the following constitution. At least one side of the polyester film is coated with 1 to 1 of the phosphoric acid ester salt (A)
An antistatic film provided with an antistatic coating film formed by applying an aqueous coating solution containing a composition of 40% by weight, drying and stretching.

The present invention will be described in detail below.

[Base Film] In the present invention, the base film is a polyester film, and the polyester constituting the film is a linear polyester composed of a dicarboxylic acid component and a glycol component.

Examples of the dicarboxylic acid component include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, hexahydroterephthalic acid, 4,4'-diphenyldicarboxylic acid, adipic acid, sebacic acid and dodecanedicarboxylic acid. Among them, terephthalic acid and 2,6-naphthalenedicarboxylic acid are particularly preferable because they have excellent mechanical properties and thermal properties of the polyester film.

Examples of the glycol component include ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol. , Cyclohexanedimethanol, polyethylene glycol, polytetramethylene glycol and the like can be mentioned, and ethylene glycol is particularly preferable since the polyester film is excellent in mechanical properties and thermal properties.

As the polyester, polyethylene terephthalate or polyethylene-2,6-naphthalate can be preferably exemplified. The polyethylene terephthalate or polyethylene-2,6-naphthalate may be a polyester obtained by copolymerizing the above-mentioned dicarboxylic acid component or glycol component, and the polyester may be a polyfunctional carboxylic acid component having a functionality of 3 or more or a polyol component. It may be a polyester copolymerized in a small amount in a linear range (for example, 5 mol% or less). Such a polyester can be produced by a conventional method, and it is preferable that the average molecular weight is 10,000 or more because the mechanical properties of the film will be good.

The above polyester may contain organic or inorganic fine particles as a lubricant, for example, in an amount of 0.001 to 5% by weight in order to improve the slipperiness of the film. Specific examples of such fine particles include calcium carbonate, calcium oxide, amylnium oxide, titanium oxide, graphite, kaolin, silica, alumina,
Silicon oxide, zinc oxide, carbon black, silicon carbide, tin oxide, acrylic resin particles, crosslinked polystyrene resin particles,
Preferable examples are melamine resin particles and silicone resin particles.

In addition to the above-mentioned fine particles, a colorant, a known antistatic agent, antioxidant, organic lubricant, catalyst, fluorescent whitening agent, plasticizer, cross-linking agent, slip agent, ultraviolet absorber, other resin, etc. are required. Can be added according to

The thickness of the polyester film is preferably 1 to 300 μm after stretching. A transparent polyester film or a white polyester film can be used as the base film depending on the use of the antistatic film. When the transparent polyester film is used, the light transmittance is preferably 60% or more, and the white polyester film is used. In this case, for example, it is preferable that the light transmittance of titanium oxide, barium sulfate, silicon oxide or the like is 5 to 30% by weight and the light transmittance is less than 60%. A white antistatic film using a white polyester film as a base film is particularly preferably used for a magnetic card.

The polyester film of the present invention is
It can be manufactured by a conventionally known method. For example, it can be produced by melting the polyester and casting it on a cooling drum to obtain an unstretched film, and then stretching the unstretched film in the machine direction and then in the transverse direction. Further, it can be stretched again in the machine direction and / or the transverse direction. The stretching treatment is performed by the second-order transition point (T
g) It is preferable to carry out stretching at a temperature higher than 2) in each direction by a factor of 2 or more, more preferably 3 or more. At that time, the area stretching ratio is preferably 8 times or more, and more preferably 9 times or more. The upper limit of the area draw ratio depends on the use of the film, but is preferably 35 times, further preferably 30 times. The oriented crystallization can be completed by heat treatment after stretching.

[Phosphoric acid ester salt (A)] In the present invention, the antistatic coating film contains an aqueous composition containing 1 to 40% by weight of the phosphoric acid ester salt (A) on at least one side of a polyester film. It is prepared by applying a coating liquid, drying and stretching. The phosphoric acid ester salt (A) is a compound having a phosphoric acid ester base in the molecule and is represented by the following general formula.

[0018]

Embedded image (OM) P (═O) (RO) ₂ (OM) ₂ P (═O) (RO) (OM) ₃ P═O [wherein R is an alkyl group having 1 to 4 carbon atoms, Polyalkylene oxide group; M represents a monovalent metal element, ammonium group, primary to quaternary ammonium group]

The above-mentioned alkyl group having 1 to 4 carbon atoms is a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a s-butyl group or a t-butyl group, and a polyalkylene oxide group. Examples thereof include a polyethylene oxide group, a polypropylene oxide group, a polyethylene oxide / polypropylene oxide copolymer group and the like, and examples of the monovalent metal element include N.
a, K, Li, etc. can be mentioned. Moreover, NH ₄ and an ammonium group, and primary to quaternary ammonium group ^{_{NH 3 R 1 1, NH 2}} R 1 2, NH 1 R 1 3, NR 1 4
(R ¹ is an alkyl group having 1 to 4 carbon atoms).

[Binder Resin (B)] The antistatic coating film of the present invention comprises a composition containing the binder resin (B) in order to make the adhesion between the coating film and the base film stronger. It is preferable. The binder resin (B) means polyester resin (B-1), acrylic resin (B-2) and acrylic modified polyester resin (B
-3) At least one resin selected from the group consisting of:

[Polyester Resin (B-1)] The polyester resin (B-1) is a linear polyester having a dicarboxylic acid component and a glycol component as constituent components.

As the dicarboxylic acid component, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 4,4 '
-Diphenyldicarboxylic acid, adipic acid, sebacic acid,
Preferable examples include dodecanedicarboxylic acid and hexahydroterephthalic acid.

As the glycol component, ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, diene Preferable examples include propylene glycol, triethylene glycol, bisphenol A-alkylene oxide adduct, hydrogenated bisphenol A-alkylene oxide adduct, 1,4-cyclohexanedimethanol, polyethylene glycol, and polytetramethylene glycol.

The polyester resin (B-1) is preferably copolymerized with a component containing a sulfonate group in order to impart hydrophilicity. Polyester resin (B-1)
It is preferable to impart hydrophilicity to the composition because the dispersibility in the aqueous coating solution becomes good. Examples of such components include 5-N
a Sulfoisophthalic acid, 5-K sulfoisophthalic acid, etc. can be mentioned.

The polyester resin (B-1) is a small amount (for example, 5 mol% or less) of a polyfunctional carboxylic acid component having a functionality of three or more and a polyol component in a range that forms a substantially linear polymer.
It may be a copolymer. Such trifunctional or higher polycarboxylic acid, as the polyol, trimellitic acid,
Pyromellitic acid, dimethylolpropionic acid, glycerin, trimethylolpropane and the like can be exemplified.

[Acrylic Resin (B-2)] The acrylic resin (B-2) is, for example, ethyl acrylate, methyl acrylate, acrylic acid, butyl acrylate, sodium acrylate, ammonium acrylate, ethyl methacrylate, methacrylic acid. Methyl acid, methacrylic acid, butyl methacrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, acrylamide, methacrylamide, N-
It is a polymer or copolymer mainly composed of an acrylic monomer such as methoxymethylacrylamide, N-methylolacrylamide, etc., and is styrene, α-methylstyrene, sodium styrenesulfonate, vinyl chloride, vinylidene chloride, acetic acid. It may be a copolymer containing vinyl, vinyl ether, sodium vinyl sulfonate, sodium methacrylic acid, etc. as a copolymerization component.

[Acrylic modified polyester resin (B-
3)] Acrylic modified polyester resin (B-3) is ethyl acrylate, methyl acrylate, acrylic acid, butyl acrylate, sodium acrylate, ammonium acrylate, methacrylic acid in the presence of the polyester resin (B-1). Ethyl acid, methyl methacrylate, methacrylic acid,
Butyl methacrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, acrylamide, methacrylamide, N-methoxymethyl acrylamide, N-
A copolymer made by polymerizing acrylic monomers such as methylol acrylamide, styrene,
It may contain a monomer such as α-methylstyrene, sodium styrene sulfonate, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl ether, sodium vinyl sulfonate, sodium methallylate as a copolymerization component.

[Component (C) Containing Surfactant] In the present invention, the composition of the antistatic coating film has a good dispersibility in an aqueous coating liquid, so that the interface It is preferable that the component (C) containing an activator is contained. The component (C) containing a surfactant is a component containing a surfactant such as polyoxyethylene nonylphenyl ether, and the components other than the surfactant include an antioxidant,
Antistatic agents other than phosphoric acid ester salt (A), colorants, pigments, optical brighteners, plasticizers, cross-linking agents, lubricants, lubricants (lubricity imparting agents such as wax), ultraviolet absorbers, binder resins ( Resins other than B) can be mentioned.

Resins other than the binder resin (B) are
It can be added in order to adjust the adhesive strength between the coating film and the base film or to adjust the blocking resistance of the antistatic film. Examples of such resin include polyurethane resin, epoxy resin, vinyl resin, polyether resin, water-soluble resin and the like.

Further, the above-mentioned lubricant can be added in order to improve the slipperiness of the surface of the antistatic coating film and the blocking resistance of the film. Examples of such a lubricant include polystyrene resin, acrylic resin,
Examples thereof include fine particles of melamine resin, silicone resin, fluorine resin, urea resin, benzoguanamine resin, polyamide resin, polyester resin, and the like, and fine particles of crosslinked resin may be used. Fine particles of these resins are
It may be thermoplastic or thermosetting as long as it is contained in the antistatic coating in the form of fine particles.

[Antistatic Coating] The antistatic coating in the present invention is a coating comprising a composition containing 1 to 40% by weight of the above-mentioned phosphoric acid ester salt (A). It is preferable that the coating film comprises a composition in which the component (C) containing (B) and the surfactant is contained in the following formulas (I) and (II).

[0032]

## EQU2 ## [A] + [B] + [C] = 100% by weight (Formula I) 0.01 ≦ [A] / ([A] + [B]) ≦ 0.50 (Formula II) [In the above (Formula I) and (Formula II), [A] is a phosphate ester salt (A), [B] is a binder resin (B),
[C] represents the weight% of the component (C) containing the surfactant in the composition. ]

If the proportion of the phosphate ester salt (A) is less than 1% by weight, the antistatic property is insufficient, and if it exceeds 40% by weight, it is difficult to uniformly apply the antistatic coating film. Become.

When the ratio of the phosphoric acid ester salt (A), the binder resin (B) and the component (C) containing a surfactant is within the ranges of the above (formula I) and (formula II), the antistatic property is obtained. An excellent antistatic film having excellent adhesion between the antistatic coating film and the base film is obtained, which is preferable.

[Aqueous Coating Liquid] In the present invention, an antistatic coating film is coated on at least one side of a polyester film by applying an aqueous coating liquid containing the above composition, followed by heating and drying and stretching. The solid content concentration of this aqueous coating solution is 1 to
30% by weight is preferable, and 2 to 20% by weight is particularly preferable. When the solid content concentration is within this range, the viscosity of the aqueous coating liquid becomes suitable for coating, which is preferable. The aqueous coating solution used in the present invention can be used in any form such as an aqueous solution, an aqueous dispersion, and an emulsion. Further, the aqueous coating liquid may contain a small amount of solvent.

[Coating of antistatic coating film] In the present invention, the method for coating the polyester film with the aqueous coating solution is as follows.
Any known coating method can be applied, for example, gravure coating method, reverse roll coating method, die coating method, kiss coating method, reverse kiss coating method, offset gravure coating method, Meyer bar coating method, roll brush method, spray coating method, air. The knife coating method, the impregnation method, the curtain coating method and the like can be applied alone or in combination. The WET coating amount of the aqueous coating liquid is preferably 1 to ²⁰ g, and particularly preferably ^{2 to} 12 g per 1 m ² of the running film. When the coating amount is within this range, drying is easy and coating spots are less likely to occur, which is preferable.

The polyester film to which the aqueous coating liquid is applied in the present invention is a stretchable polyester film, for example, an unstretched film obtained by heat-melting polyester to form a film as it is; the unstretched film in the longitudinal direction (longitudinal direction). ) Or a uniaxially-stretched film stretched in either the transverse direction (width direction); a biaxially-stretched film in which a longitudinally or transversely uniaxially stretched film is sequentially stretched in the transverse or longitudinal direction (further stretchable). Or a biaxially stretched film obtained by simultaneously stretching the unstretched film in both the machine direction and the transverse direction (further stretchable); heat fixing and / or heat relaxation of the biaxially stretched film (further stretchable) A biaxially stretched heat-treated film may be mentioned.

The thickness of the polyester film is preferably 10 to 1000 μm for the unstretched film, 2 to 500 μm for the uniaxially stretched film, and 1 to 300 μm for the biaxially stretched film and the biaxially stretched heat-treated film.

When the aqueous coating solution is applied to a uniaxially stretched film of the polyester film, especially a longitudinally uniaxially stretched film, the antistatic coating becomes adhesive or firm, and the antistatic property is improved efficiently. It is preferable because a film can be produced. For example, polyester is heat-melted, extruded into a sheet and cooled to obtain an unstretched film, and the unstretched film is stretched in the machine direction to form a uniaxially stretched film, and then an aqueous coating solution is applied and dried to obtain a transverse direction. The film is stretched, and if necessary, re-stretched in the longitudinal and transverse directions and then heat-treated to prepare an antistatic film coated with an antistatic coating.

The thickness of the applied antistatic coating is 0.005 to
3 μm, particularly 0.015 to 1 μm is preferable. If the thickness of the coating film is less than 0.005 μm, the antistatic property may be insufficient, and if it exceeds 1 μm, the coating film may be easily scraped or the shape of the coating film surface may be nonuniform. Absent.

[Drying and Stretching Conditions] After applying the aqueous coating liquid in the present invention, the drying temperature is preferably 80 to 150 ° C. because the coating liquid can be dried quickly. The heating for this drying can also serve as the heating during the process of stretching the polyester film. The heat treatment temperature of the polyester film may be 180 to 250 ° C.

[Antistatic Film] The antistatic film of the present invention is a transparent antistatic film having a light transmittance of 60% or more, or a white antistatic film having a light transmittance of less than 60%, depending on the application. Can be The base film of the transparent antistatic film is a polyester film having a light transmittance of 60% or more, and the base film of the white antistatic film is a white polyester having a light transmittance of less than 60%, particularly 30% or less. It is preferable to use a film.

A white antistatic film using a white polyester film as a base film is particularly preferably used for a magnetic card. The magnetic card here is
For example, it is a card in which a magnetic recording layer is provided on one surface of an antistatic film and a pattern layer or the like is printed on the other surface by UV ink or the like, and the thickness of the film is, for example, 100 to 30.
Those having a thickness of 0 μm, particularly 180 to 250 μm are preferably used.

[0044]

EXAMPLES The present invention will be described in more detail with reference to examples. Each characteristic value was measured by the following method.

1. Surface resistivity After leaving the sample film at 21 ° C. × 52% RH for 19 hours, the surface resistivity of the film coated surface was measured using a vibration capacitance type potentiometer TR-84M type (manufactured by Takeda Riken). The applied voltage was 100 Volt.

[Example 1] Polyethylene terephthalate having an intrinsic viscosity of 0.65 was melted, cast on a cooling drum, and then stretched 3.5 times in the machine direction at 92 ° C to obtain a uniaxially stretched film. On one side of this uniaxially stretched film, C
₈ H ₁₇ OP (= O) (ONa) ₂ (a-1) 8% by weight,
H (OCH ₂ CH) ₁₃ OP (= O) (ONa) (OC ₁₀
H ₂₁ ) (a-2) 21% by weight, dicarboxylic acid component being terephthalic acid (56 mol%), isophthalic acid (38 mol%)
And a copolymer of 5-K sulfoisophthalic acid (6 mol%), a glycol component of ethylene glycol (48 mol%), diethylene glycol (10 mol%) and neopentyl glycol (42 mol%) (average molecular weight: 19,40).
0, glass transition temperature: 52 ° C.) 48% by weight of polyester resin (b-1), 10% by weight of polyethylene glycol, and 13% by weight of polyoxyethylene nonylphenyl ether. Was applied. Next, the coated film was dried at 95 ° C., stretched at 109 ° C. in the transverse direction by 3.6 times, and heat-treated at 219 ° C. to prepare an 80 μm-thick film coated with an antistatic coating. The thickness of the antistatic coating of the film is 0.16
μm, and the light transmittance was 85%. The characteristics of this film are shown in Table 1.

[Comparative Example 1] Table 1 shows the characteristics of the film obtained in the same manner as in Example 1 except that the aqueous liquid was not applied.

[Examples 2 to 9 and Comparative Examples 2 to 4] The characteristics of the film obtained in the same manner as in Example 1 are shown except that the composition of the coating liquid and the coating thickness are changed as shown in Table 1. Shown in 1.

Example 10 Polyethylene terephthalate having an intrinsic viscosity of 0.64 containing 12% by weight of titanium oxide was used as the polyester for the base film, the film thickness was 150 μm, and the composition of the coating liquid and the coating thickness were shown in Table 1. A film having a light transmittance of 2% was obtained in the same manner as in Example 1 except that the film was changed as described in 1 above. The characteristics of this film are shown in Table 1.

[0050]

[Table 1]

In the antistatic coating composition shown in Table 1, [a-1], [a-2], [a-3] and [a-] of the antistatic agent (A).
4], [b-1] and [b-] of the binder resin (B).
2], [b-3] and [C-1] and [C-1] of the component (C).
-2] and [C-3] are the following copolymers or mixtures, respectively.

[0052]

## STR2 ## _{[a-1]: C 8} H 17 OP (= O) (ONa) 2 [a-2]: H (OCH 2 CH) 13 OP (= O) (ON
a) (OC ₁₀ H ₂₁ ) [a-3]: ethyl acrylate (9 mol%), soda vinyl sulfonate (19 mol%), butyl acrylate (1
3 mol%), ammonium acrylate (6 mol%), methyl methacrylate (45 mol%), 2-hydroxyethyl acrylate (8 mol%) copolymer (average molecular weight:
86,400, glass transition temperature 36 ° C.) [a-4]: ethyl acrylate (6 mol%), sodium styrenesulfonate (85 mol%), methyl acrylate (3 mol%), methyl methacrylate (3 mol) %), 2-
Copolymer of hydroxyethyl acrylate (3 mol%) (average molecular weight: 73,000, glass transition temperature 38 ° C)

[0053]

Embedded image [b-1]: terephthalic acid (56 mol%), isophthalic acid (38 mol%), 5-K sulfoisophthalic acid (6 mol%), glycol component is ethylene glycol (48 mol%), diethylene glycol (10 mol%)
Copolymer of neopentyl glycol (42 mol%) (average molecular weight: 19,400, glass transition temperature: 52 ° C.) [b-2]: polyester resin (50 wt%) of [b-1] and acrylic acid Ethyl (11 mol%), butyl acrylate (21 mol%), sodium acrylate (5 mol%), ethyl methacrylate (47 mol%), glycidyl methacrylate (8 mol%), 2-hydroxyethyl acrylate (3 Mol%), N-methoxymethylacrylamide (5 mol%) copolymer (average molecular weight: 125,000)
0) (50% by weight) mixture [b-3]: 62% by weight of polyester resin [b-1]
With respect to ethyl acrylate (29 mol%), butyl acrylate (11 mol%), ammonium acrylate (3 mol%), methyl methacrylate (38 mol%), glycidyl methacrylate (10 mol%), 2- Copolymer having a molecular weight of 24,500 grafted with 38% by weight of a copolymerization component of hydroxyethyl acrylate (6 mol%) and N-methoxymethyl acrylamide (3 mol%), glass transition temperature 47 ° C.

[0054]

[C-1]: Polyoxyethylene nonylphenyl ether 13 parts by weight Polyethylene glycol (molecular weight: 22,000) 10 parts by weight Mixture [C-2]: Polyethylene glycol (molecular weight: 22,000) 29 parts by weight Parts Polyvinyl alcohol (molecular weight: 39,000) 18 parts by weight Silica particles (average particle diameter: 60 mμ) 15 parts by weight Mixture [C-3]: polyoxyethylene nonylphenyl ether 13 parts by weight Polyethylene glycol (molecular weight: 22,000) ) 10 parts by weight Polyvinyl alcohol (molecular weight: 39,000) 42 parts by weight Silica particles (average particle size: 60 mμ) 23 parts by weight Mixture

[0055]

The antistatic film of the present invention has excellent antistatic properties and is useful for magnetic recording media such as magnetic cards, packaging materials, photographic materials, graphic materials, plate-making films, OHP films and the like.

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Claims (4)

[Claims] 1. An antistatic coating prepared by applying an aqueous coating solution containing a composition containing 1 to 40% by weight of a phosphoric acid ester salt (A) to at least one side of a polyester film, and drying and stretching. An antistatic film provided with a film. 2. The aqueous coating liquid is a phosphoric acid ester salt (A).
And polyester resin (B-1), acrylic resin (B-
2) and at least one binder resin (B) selected from the group consisting of the acrylic modified polyester resin (B-3) and the component (C) containing a surfactant have the following (formula I) and The antistatic film according to claim 1, which is an aqueous coating liquid containing a composition within the range of (Formula II). ## EQU1 ## [A] + [B] + [C] = 100% by weight (Formula I) 0.01 ≦ [A] / ([A] + [B]) ≦ 0.50 (Formula II) [In the above (Formula I) and (Formula II), [A] is a phosphate ester salt (A), [B] is a binder resin (B),
[C] represents the weight% of the component (C) containing the surfactant in the composition. ] 3. A polyester film having a light transmittance of 6
The antistatic film according to claim 1, which is a white polyester film of less than 0% and is used for a magnetic card. 4. A polyester film having a light transmittance of 6
The antistatic film according to claim 1, which is a transparent polyester film containing 0% or more.