JP2002088180A - Antistatic laminate polyester film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antistatic laminated polyester film which has excellent adhesivity to water coatings and has excellent antistaticity under low humidity, blocking resistance, backside print transfer resistance, scratch resistance and recovery. SOLUTION: This antistatic laminated polyester film is characterized by disposing a coating film obtained by coating at least one side of a polyester film with a water coating comprising (A) 40 to 85 wt.% of at least one binder resin selected from copolyester resins and acrylic copolymers, (B) 5 to 50 wt.% of an antistatic agent having structural repeating units represented by the general formula (1) [R1 and R2 are each H or CH3; R3 is a 2 to 10C alkylene; R4 and R5 are each a 1 to 5C saturated hydrocarbon group; R6 is a 2 to 10C alkylene; (m) is 1 to 20; (n) is 1 to 40; Y- is a halogen ion, an alkylsulfonate or the like] as a main component, (C) 3 to 25 wt.% of a water-soluble polymer and (D) 1 to 15 wt.% of a surfactant, drying the applied coating and then stretching the film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antistatic laminated polyester film, and more particularly, to adhesion to an aqueous paint, antistatic properties, back transferability, abrasion resistance, blocking resistance, recoverability, printability, etc. Excellent in plate making films, electronic materials, OHP films, packaging films, labels, magnetic cards (eg telephone cards, prepaid cards)
The present invention relates to an antistatic laminated polyester film useful for such purposes.

[0002]

2. Description of the Related Art Polyester films such as polyethylene terephthalate and polyethylene 2,6-naphthalate are used for plate making films, electronic materials, OHP films,
It is widely used for general industrial materials such as packaging films, labels and magnetic cards, and for magnetic recording materials such as magnetic tapes. As the polyester film, a film made of polyethylene terephthalate or polyethylene naphthalate having excellent water resistance, chemical resistance, mechanical strength, dimensional stability, and electrical properties has been used or studied. It has the disadvantage that it is easy. When the film is charged, dirt and dust adhere to the surface, causing quality problems. Further, when an organic solvent is used in the film processing step, there is a danger of ignition due to discharge from the charged film.

[0003] As a countermeasure against such a problem caused by charging,
A method of kneading an anionic compound such as an organic sulfonic acid salt group, a metal powder, a carbon powder or the like into a polyester film,
A method of evaporating a metal compound on the surface of a polyester film has been proposed and put to practical use. However, such a method has a problem that the transparency of the film is reduced and a problem that processing cost is high.

As another method, various methods for forming an antistatic coating film on a film surface have been proposed. As an antistatic agent to be contained in the antistatic coating film, a low-molecular type or a high-molecular type is known, but each has advantages and disadvantages. Therefore, the antistatic agent can be properly used according to its characteristics. For example, as the low molecular weight antistatic agent, a surfactant type anionic antistatic agent such as a long chain alkyl compound having a sulfonate group (JP-A-4-28728) and the like, Examples of the antistatic agent include polymers having an ionized nitrogen element in the main chain (JP-A-3-255139, JP-A-4-288127, JP-A-6-320390), and sulfonate-base modified polystyrene. (Japanese Patent Laid-Open No. 5
No. 322394) is known.

However, in an antistatic coating film using a low-molecular type antistatic agent, there is a problem that a part of the antistatic agent moves in the coating film, accumulates at the interface, and migrates to the opposite surface of the film. In addition, there is a problem that the antistatic property decreases with time. On the other hand, in the case of an antistatic coating film using a polymer type antistatic agent, a large amount of an antistatic agent is required to obtain good antistatic properties, or a thick antistatic coating film is required. Is not economical because it is necessary to form In addition, when a scrap film that has not become a product (for example, a film end portion cut and removed in a manufacturing process) is collected and used as a reclaimed material for film production, it is included in the reclaimed material during melt film formation. There are problems such as the coating film components being thermally degraded and the resulting film being markedly colored and lacking practicality (recoverability is poor). In addition, disadvantages such as difficulty in peeling (blocking) between the films and easiness of shaving of the coating film occur, and a solution to the problem is desired.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art and to provide an antistatic film at low processing cost without performing a pretreatment such as a corona discharge treatment. It is an object of the present invention to provide an antistatic laminated polyester film having excellent antistatic properties, adhesion to a water-based paint, backside transferability, abrasion resistance, blocking resistance, and recoverability.

[0007]

According to the present invention, an object of the present invention is to provide, on at least one side of a polyester film,
At least one binder resin (A) selected from a copolymerized polyester resin and an acrylic copolymer;
5% by weight, 5 to 50% by weight of an antistatic agent (B) containing a repeating unit having a structure represented by the following formula (1) as a main component, 3 to 25% by weight of a water-soluble polymer (C), and a surfactant ( D)
An aqueous coating liquid containing a composition consisting of 1 to 15% by weight is applied,
This is achieved by an antistatic laminated polyester film, which is provided with a coating film obtained by drying and stretching.

[0008]

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Wherein R ¹ and R ² are each H or CH ₃ , R ³ is an alkylene group having 2 to 10 carbon atoms, R ⁴ ,
R ⁵ is a saturated hydrocarbon group having 1 to 5 carbon atoms, R ⁶ is an alkylene group having 2 to 10 carbon atoms, m is a number of 1 to 20,
n is a number from 1 to 40; Y ^- is a halogen ion, a mono- or polyhalogenated alkyl ion, a nitrate ion, a sulfate ion, an alkyl sulfate ion, a sulfonate ion or an alkyl sulfonate ion.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

[Polyester] In the present invention, the polyester is a linear saturated polyester formed from a dicarboxylic acid component and a glycol component. The dicarboxylic acid component includes terephthalic acid, isophthalic acid, 2,6
-Naphthalenedicarboxylic acid, hexahydroterephthalic acid, 4,4'-diphenyldicarboxylic acid, adipic acid,
Sebacic acid, dodecanedicarboxylic acid and the like can be exemplified. Particularly, terephthalic acid and 2,6-naphthalenedicarboxylic acid are preferred from the viewpoint of the mechanical properties of the film.

The glycol components include ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, cyclohexanedimethanol, polyethylene glycol. , Etc. can be exemplified. Particularly, ethylene glycol is preferred from the viewpoint of the rigidity of the film.

Of these polyesters, polyethylene terephthalate or polyethylene-2,6-naphthalate is preferred because a film having excellent mechanical properties (for example, high Young's modulus) and excellent thermal properties (for example, heat-resistant dimensional stability) can be obtained. .

The above polyester may be a copolyester obtained by copolymerizing the above dicarboxylic acid component or glycol component as the third component, and a polyester from which a trifunctional or higher polyvalent carboxylic acid component or a polyol component can be substantially obtained. A polyester copolymerized in a small amount within a linear range (for example, 5 mol% or less) may be used.

Such a polyester can be produced by a conventional method, and it is preferable that the intrinsic viscosity of the polyester is 0.45 dl / g or more because mechanical properties such as high rigidity of the film are improved.

The above polyester has an average particle size of 0.0 as a lubricant in order to improve the slipperiness of the film.
Organic or inorganic fine particles of about 1 to 2.0 μm can be contained, for example, in a blending ratio of 0.01 to 5% by weight. Specific examples of such fine particles include silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, kaolin, talc, titanium oxide, inorganic fine particles such as barium sulfate, a crosslinked silicone resin, a crosslinked polystyrene resin,
Organic fine particles made of a heat-resistant polymer such as a crosslinked acrylic resin, a urea resin, a melamine resin and the like can be preferably exemplified.

In addition to the fine particles, coloring agents, known antistatic agents, organic lubricants (sliding agents), catalysts, stabilizers, antioxidants, ultraviolet absorbers, optical brighteners, polyethylene, polypropylene, ethylene-propylene copolymer If necessary, other resins such as olefin-based ionomers may be contained.

[Coating Film] In the present invention, the coating film (antistatic coating) provided on at least one side of the polyester film is at least one kind of binder resin (A) selected from a copolymerized polyester resin and an acrylic copolymer.
40 to 85% by weight, 5 to 50% by weight of an antistatic agent (B) containing a repeating unit having a structure represented by the following formula (1) as a main component, 3 to 25% by weight of a water-soluble polymer (C), and surface activity An aqueous coating liquid containing a composition comprising 1 to 15% by weight of the agent (D) can be applied, dried, and stretched to provide.

[0019]

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Wherein R ¹ and R ² are each H or CH ₃ , R ³ is an alkylene group having 2 to 10 carbon atoms, R ⁴ ,
R ⁵ is a saturated hydrocarbon group having 1 to 5 carbon atoms, R ⁶ is an alkylene group having 2 to 10 carbon atoms, m is a number of 1 to 20,
n is a number from 1 to 40; Y ^- is a halogen ion, a mono- or polyhalogenated alkyl ion, a nitrate ion, a sulfate ion, an alkyl sulfate ion, a sulfonate ion or an alkyl sulfonate ion.

In the present invention, at least one kind of binder resin (A) selected from a copolymerized polyester resin and an acrylic copolymer, an antistatic agent (B) represented by the above formula (1), a water-soluble polymer (C) ) And the surfactant (D), it is necessary that the proportion of the binder resin (A) is 40 to 85% by weight, preferably 50 to 80% by weight. If the proportion is less than 40% by weight, the adhesion of the coating film (antistatic coating) to the polyester film is insufficient, which is not preferable. On the other hand, if it exceeds 85% by weight, the blocking property of the coated film is undesirably deteriorated. The ratio of the antistatic agent (B) is 5
５０50% by weight, preferably 10
４０40% by weight. If the proportion is less than 5% by weight, the antistatic property is insufficient, while if it exceeds 50% by weight, the adhesion of the coating film to the polyester film is insufficient, which is not preferable. The ratio of the water-soluble polymer (C) is 3 to 25% by weight.
And preferably 5 to 15% by weight. If this proportion is less than 3% by weight, the adhesion to the water-based paint will be insufficient, which is not preferable. If it exceeds 25% by weight, the adhesion of the coating film to the polyester film may be insufficient, or the blocking resistance may be insufficient. Also,
The proportion of the surfactant (D) needs to be 1 to 15% by weight, and preferably 3 to 10% by weight. If this proportion is less than 1% by weight, the wettability of the aqueous coating liquid to the polyester film may be insufficient, while if it exceeds 15% by weight, the adhesion of the coating film to the polyester film may be insufficient or the blocking resistance may be insufficient. May be undesirable.

[Binder Resin] In the present invention, the binder resin (A) is at least one resin selected from a copolymerized polyester resin and an acrylic copolymer.

The acid components constituting the copolymerized polyester resin include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, adipic acid, sebacic acid and phenylindanedicarboxylic acid. Acids, dimer acids and the like can be exemplified. Two or more of these components can be used. Furthermore, maleic acid, fumaric acid,
An unsaturated polybasic acid such as itaconic acid or a hydroxycarboxylic acid such as p-hydroxybenzoic acid or p- (β-hydroxyethoxy) benzoic acid can be used in a small proportion. The proportion of the unsaturated polybasic acid component or hydroxycarboxylic acid component is at most 10 mol%, preferably 5 mol% or less.

The polyol component includes ethylene glycol, 1,4-butanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, xylylene glycol, Methylolpropionic acid, glycerin, trimethylolpropane, poly (ethyleneoxy) glycol, poly (tetramethyleneoxy) glycol, and ethylene oxide adducts and propylene oxide adducts of bisphenol A represented by the following formulas (2) and (3) Objects and the like can be exemplified. Two or more of these can be used.

[0025]

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[0026]

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Among such polyol components, ethylene glycol, an ethylene oxide adduct of bisphenol A, a propylene oxide adduct, and 1,4-butanediol are preferable, and ethylene glycol is more preferable.

The copolymerized polyester resin may be copolymerized with a small amount of a compound having a sulfonate group or a compound having a carboxylate group in order to facilitate the formation of an aqueous liquid (aqueous solution or aqueous dispersion). Is possible, which is preferred.

Examples of the compound having a sulfonic acid group include 5-Na sulfoisophthalic acid, 5-ammonium sulfoisophthalic acid, 4-Na sulfoisophthalic acid, 4-methylammonium sulfoisophthalic acid,
Na sulfoisophthalic acid, 5-K sulfoisophthalic acid,
Preferable examples include alkali metal sulfonic acid salts such as 4-K sulfoisophthalic acid, 2-K sulfoisophthalic acid, and sodium sulfosuccinic acid, and amine sulfonic acid salts. Examples of the compound having a carboxylic acid group include, for example, trimellitic anhydride, trimellitic acid, pyromellitic anhydride, pyromellitic acid, trimesic acid, cyclobutanetetracarboxylic acid, dimethylolpropionic acid, etc. Metal salts and the like. The free carboxyl group is converted to a carboxylate group by the action of an alkali metal compound or an amine compound after copolymerization.

The copolymerized polyester resin can also be used as a modified polyester copolymer, for example, a block polymer obtained by modifying the above polyester copolymer with an acryl, polyurethane, silicone, epoxy, phenol resin or the like, or as a graft polymer.

Such a copolymerized polyester resin can be produced by a conventionally known or used polyester production technique. For example, 2,6-naphthalenedicarboxylic acid or its ester-forming derivative (especially dimethyl ester), isophthalic acid or its ester-forming derivative (especially dimethyl ester) and trimellitic anhydride are propylene oxide adducts of ethylene glycol and bisphenol A To form a monomer or oligomer, followed by a polycondensation reaction under vacuum to obtain a predetermined intrinsic viscosity (intrinsic viscosity measured at 35 ° C. with o-chlorophenol of 0.3).
2-0.8 is preferred. )
Further, it can be produced by a method in which a free carboxy group is reacted with an alkali compound or an amine compound to form a salt. At that time, it is preferable to use a catalyst for accelerating the reaction, for example, an esterification or transesterification catalyst, a polycondensation catalyst, and the like, and various additives such as a stabilizer can be added.

The acrylic copolymer used as the binder resin (A) in the present invention includes acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, sodium acrylate, ammonium acrylate, 2-hydroxy Ethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, sodium methacrylate, ammonium methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate, acrylic methacrylate, sodium vinyl sulfonate, sodium methallylsulfonate, styrene Sodium sulfonate, acrylamide,
Methacrylamide, N-methylol methacrylamide and the like can be exemplified. These monomers can be used in combination with other unsaturated monomers such as styrene, vinyl acetate, acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, and divinylbenzene.

Further, as the acrylic copolymer, a modified acrylic copolymer, for example, a block polymer or a graft polymer obtained by modifying the above acrylic copolymer with polyester, polyurethane, silicone, epoxy, phenolic resin, etc. Can also.

[Antistatic Agent] The antistatic agent (B) in the present invention is a compound mainly composed of a repeating unit having the structure represented by the following formula (1).

[0035]

Embedded image

Wherein R ¹ and R ² are each H or CH ₃ , R ³ is an alkylene group having 2 to 10 carbon atoms, R ⁴ ,
R ⁶ is a saturated hydrocarbon group having 1 to 5 carbon atoms, R ⁶ is an alkylene group having 2 to 10 carbon atoms, m is a number of 1 to 20,
n is a number from 1 to 40; Y ^- is a halogen ion, a mono- or polyhalogenated alkyl ion, a nitrate ion, a sulfate ion, an alkyl sulfate ion, a sulfonate ion or an alkyl sulfonate ion.

Of the above antistatic agents, Y in the formula (1)
^- is R ⁷ SO ₃ ^- alkyl sulfonate ion (wherein, R ⁷ is a saturated hydrocarbon group having 1 to 5 carbon atoms) represented by a, - (OR ³⁾ m-of R ³ is an ethylene group, the number m is ^{1~20, - (R 6 O)} R 6 in n- is an ethylene group, and n is a number from 1 to 40, the adhesion between the coating film and the polyester film, the coating film It is preferable because it has good heat resistance and particularly excellent antistatic properties.

Further, the antistatic agent (B) is a compound of the formula (1)
Y inside^-But CH_ThreeSO_Three ^-, C_TwoH_FiveSO_Three ^-Or C_ThreeH₇
SO_ThreeAnd-(OR^Three) M- is-(OC_TwoH_Four) M-
And m is preferably 1 to 5. Also,
− (R⁶O) n- is-(C_TwoH _FourO) n- and n
Is preferably 1 to 10.

The antistatic agent (B) can be preferably produced, for example, by the following method. That is, the acrylate monomer is converted into a polyacrylate having a weight average molecular weight of 2,000 to 100,000 by emulsion polymerization, and then N, N-dialkylaminoalkylamine (for example, N, N-dimethylaminopropylamine,
(N, N-diethylaminopropylamine, etc.) and amidation, and finally a quaternary hydroxyalkylation reaction to introduce a quaternary cation pair.

The average molecular weight (number average molecular weight) of the antistatic agent (B) is optional, but is preferably from 3,000 to 300,000, more preferably from 5,000 to 100,000. If the average molecular weight is less than 3,000, the back transferability of the antistatic agent tends to deteriorate, while the average molecular weight is less than 3,000.
If it exceeds 00, the viscosity of the aqueous coating solution becomes too high, which makes it difficult to uniformly apply the film to the film, which is not preferable.

[Water-soluble polymer] The water-soluble polymer (C) is blended in the antistatic film of the present invention in order to improve the adhesion to the water-based paint. Preferred examples of the water-soluble polymer include polyvinyl alcohol and polyvinyl pyrrolidone.

The polyvinyl alcohol has a degree of saponification of 75
It is preferably about 95 mol%. If the saponification degree is less than 75 mol%, the moisture resistance of the coating film may decrease, while if it exceeds 95 mol%, the adhesion to water-based paint may decrease, which is not preferable. Further, polyvinyl alcohol is preferably cation-modified because of good adhesion to the ink image receiving layer.

Further, polyvinylpyrrolidone has a K value of 2
It is preferably from 6 to 100. If the K value is less than 26, the strength of the coating film may be weak, which is not preferred. On the other hand, if the K value exceeds 100, the adhesiveness to the water-based paint decreases, which is not preferable. The average molecular weight is 4000
A value of 0 or less is not preferred because the abrasion resistance of the coating film of the film is reduced.

[Surfactant] The antistatic coating film of the present invention has a strong adhesiveness between the coating film and the polyester film, and has a good anti-blocking property of the antistatic laminated film. And a surfactant (D). Examples of the surfactant (D) include an alkylene oxide homopolymer, an alkylene oxide copolymer, an aliphatic alcohol / alkylene oxide adduct, a long-chain aliphatic-substituted phenol / alkylene oxide addition polymer, and a polyhydric alcohol aliphatic. Nonionic surfactants such as esters and long-chain aliphatic amide alcohols and the like. Cationic or anionic surfactants such as compounds having a quaternary ammonium salt, compounds having an alkylpyridinium salt and compounds having a sulfonate salt. Can be
In particular, nonionic surfactants are preferred because they have excellent effects on the adhesion between the coating film and the base film and on the blocking resistance of the antistatic polyester film.

[Aqueous coating liquid] In the present invention, a coating film is applied by applying an aqueous coating liquid containing the composition of the above-mentioned components to at least one surface of a polyester film, drying and stretching. The coating liquid to be used is one in which the composition of the above components is dissolved and / or dispersed using water as a medium (aqueous coating liquid). The aqueous coating liquid may contain a small amount of an organic solvent for the purpose of assisting the stability of the coating liquid. Examples of the organic solvent include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexanone, n-hexane, toluene, xylene, methanol, ethanol, n-propanol, isopropanol and the like. A plurality of organic solvents may be contained.

In the present invention, the coating is preferably applied by using an aqueous coating solution containing the above-mentioned composition. This aqueous coating solution has good slipperiness on the surface of the coating and has good blocking resistance of the film. It is preferable to add a lubricant within a range that does not impair properties such as adhesiveness, in order to improve the surface roughness. Preferred examples of the lubricant include fine particles such as polystyrene resin, acrylic resin, melamine resin, silicone resin, fluorine resin, urea resin, benzoguanamine resin, polyamide resin, and polyester resin. The fine particles of these resins may be thermoplastic or thermosetting as long as the fine particles are contained in the coating. The average particle size of the fine particles is 20 to 80.
nm, and the content is preferably 5 to 20% by weight.

In the present invention, other surfactants, ultraviolet absorbers, pigments, lubricants, anti-blocking agents, water-soluble polymer resins, oxazolines, melamines are contained in the aqueous coating liquid within a range not to impair the object of the present invention. And additives such as a crosslinking agent such as epoxy and aziridine and other antistatic agents.

In the present invention, the solid content concentration in the aqueous coating solution is usually 30% by weight or less, and more preferably 0.5 to 30% by weight. If the proportion is less than 0.5% by weight, the coatability on the polyester film is insufficient, and if it exceeds 30% by weight, the appearance of the coating film is unfavorably deteriorated.

[Coating of Coating Film] In the present invention, an aqueous coating solution containing the above-mentioned components is applied to at least one surface of a polyester film. As this film, a polyester film before completion of crystal orientation is preferable. As the polyester film before the completion of the oriented crystal, an unstretched film obtained by hot-melting the polyester to form a film as it is, a uniaxially stretched film obtained by stretching the unstretched film in either the longitudinal direction or the transverse direction, A further stretchable biaxially stretched film obtained by stretching an unstretched film at a low magnification in two directions of a machine direction and a transverse direction (the biaxial film before finally being stretched in the machine direction and the transverse direction to complete orientation crystallization) Stretched film) and the like.

As a method for applying the aqueous coating solution to the polyester film, any known coating method can be applied. For example, roll coating, gravure coating, microgravure coating, reverse coating, roll brushing,
It is preferable to apply a spray coating method, an air knife coating method, an impregnation method, a curtain coating method, or the like, alone or in combination.

The amount of coating is preferably 0.5 to 50 g, more preferably 5 to 30 g, per m ² of the running film. The thickness of the final dried coating film (coating) is 0.02 to 1 μm
Is required, and the thickness is preferably 0.05 to 0.8 μm. When the thickness of the coating film is less than 0.02 μm, the antistatic property becomes insufficient. On the other hand, when the thickness exceeds 1 μm, the blocking resistance decreases, which is not preferable. Coating can be performed on only one side or on both sides depending on the use of the film. After coating, the coating is dried to form a uniform coating.

[Polyester Film] The thickness of the polyester film in the present invention is preferably from 10 to 500 μm. The lower limit of the thickness is more preferably 20 μm, and particularly preferably 50 μm. Further, the upper limit of the thickness is more preferably 300 μm, and particularly preferably 200 μm. When the thickness of the film is less than 10 μm, the stiffness of the film becomes weak,
On the other hand, if the film is too thick, for example, more than 500 μm, the film-forming properties tend to be poor.

In the present invention, after the aqueous coating solution is applied to the polyester film, drying, preferably stretching treatment is performed. This drying is preferably performed at 90 to 130 ° C. for 2 to 20 seconds. This drying can serve as a pre-heat treatment for the stretching treatment or a heat treatment for the stretching. The stretching process of the polyester film is preferably performed at a temperature of 70 to 140 ° C. in a lengthwise direction of 2.5 to 7 times, in a horizontal direction of 2.5 to 7 times, and in an area magnification of 8 times or more, and more preferably 9 to 28 times. preferable. When re-stretching, it is preferable to stretch at a magnification of 1.05 to 3 times (however, the area magnification is the same as described above). The heat-setting treatment after stretching is performed at a temperature higher than the final stretching temperature and below the melting point.
It is preferably performed for 30 seconds. For example, in the case of a polyethylene terephthalate film, it is preferable to heat set at 170 to 240 ° C. for 2 to 30 seconds.

The thus obtained antistatic laminated polyester film is excellent in antistatic properties, adhesion to water-based paints, blocking resistance, back transferability, abrasion resistance, and recoverability. It is useful as an electronic material, an OHP film, a packaging film, a label, a magnetic card (for example, a telephone card, a prepaid card) and the like.

[0055]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. The evaluation in the present invention was performed by the following method.

1. Surface resistivity (antistatic property) The surface resistivity of the sample film was measured by Takeda Riken Co., Ltd.
Using a specific resistance measuring instrument, measured temperature 23 ° C, measured humidity 6
Under the condition of 0%, the surface specific resistance (Ω / □) after one minute at an applied voltage of 500 V is measured. The specific surface resistance is 3 ×
It is preferably 10 ¹² [Ω / □] or less, more preferably 3 × 10 ¹¹ or less.

2. Adhesion with water-based paint A water-based paint (72 parts of a 60% slurry of soft calcium carbonate, 64 parts of a 10% aqueous solution of polyvinyl alcohol, styrene-butadiene-based latex 51 having a solid concentration of 48%) was applied to the coating surface of the sample film. Parts and water 113
Part) with a microgravure coater, and at 60 ° C.,
After drying for 3 minutes, an aqueous coating layer having a coating thickness of 10 μm was obtained. A cellophane tape (18 mm width; made by Nichiban) was stuck on the aqueous coating layer to a length of 15 cm, a constant load was applied on this with a 2 kg hand-operated load roll, the film was fixed, and one end of the cellophane tape was fixed to 90 cm. The peel adhesion is evaluated by peeling in the ゜ direction. Adhesion is evaluated according to the following criteria. Rank A: Water-based coating layer is not peeled at all (good adhesion of water-based paint) Rank B: Partially peels between coating film and water-based coating film in a cohesive failure state (slightly good adhesion of water-based coating) Rank C: Coating The layer between the film and the water-based paint peels off in layers (poor water-based paint adhesion)

3. Blocking resistance The laminate film coated surface and the non-coated surface of the sample film cut to a width of 50 mm were overlapped. After treating at 60 ° C. × 80% RH for 17 hours under a load of 50 kg / cm ² , the peeling force between the coated surface and the non-coated surface is measured, and the blocking resistance is evaluated as follows. Rank A: Peeling force ≦ 10 g (good blocking resistance) Rank B: 10 g <peeling force ≦ 30 g (slightly poor blocking resistance) Rank C: 30 g <peeling force (poor blocking resistance)

4. Back transferability 6 kg by applying the coated side of the sample film and the non-coated side
/ Cm ^{2 and} a load of 50 ° C. × 70% RH.
After the treatment for 7 hours, the water contact angle (θ: substitute property of backside transferability) of the non-coated surface is measured and evaluated according to the following criteria. Rank A: θ ≧ 55 ° (backside transferability is good) Rank B: 55 °> θ ≧ 48 ° (backside transferability is somewhat good) Rank C: 48 °> θ (backside transferability is poor) The water contact angle is the above sample film Was set on a contact angle measuring device (manufactured by Elma) with the non-coated side facing up, and the temperature was set to 23.
It measures by reading the contact angle 1 minute after dropping a water drop under the condition of ° C. The water contact angle of a film having no backside transferability is 60 to 72 °, the water contact angle of a film having good backside transferability is 55 ° or more, and a film having a remarkable backside transferability (poor backside transferability). Has a water contact angle of less than 48 °.

5. Using a film sample cut to a width of 20 mm, the coated surface of the film was applied to a cylindrical stainless steel fixed bar having a diameter of 10 mm, and was run for 80 m under a load of 200 g. Observe the white powder of the film and evaluate the abrasion resistance as follows. Rank A: No white powder adhered to the bar (good abrasion resistance) Rank B: White powder slightly adhered to the bar (slightly poor abrasion resistance) Rank C: Large amount of white powder adhered to the bar (poor abrasion resistance)

6. Degree of coloring (recovery) of regenerated film A film without a coating film is pulverized, and extruded to about 300
The mixture is melted at 0 ° C. to form chips, and then the obtained chips are melt-formed to form a blank film. The coloring degree of this film is defined as a blank. On the other hand, a sample film provided with a laminate coating film is pulverized, melted at about 300 ° C. in an extruder to form chips, and then melt-formed using the obtained chips to produce a reclaimed film. The degree of coloring of this film is evaluated according to the following criteria. Rank A: The degree of coloring is comparable to that of a blank film. Rank B: The film is slightly colored. Rank C: The degree of coloring of the film is large and lacks practicality.

7. Adhesiveness of UV ink After UV-curable printing ink (flash dry FDO red APN manufactured by Toyo Ink) was printed on the coating surface of the sample film with an RI tester (manufactured by Meiji Seisakusho), a medium pressure mercury lamp (80 W / cm, Curing is performed with a UV curing device (single lamp type; manufactured by Nippon Battery) to form a 3.0 μm thick UV ink layer. On this UV ink layer, scotch tape (1
(8 mm width; made by Nichiban) is applied to a length of 15 cm, a constant load is applied on this with a 2 kg hand-operated load roll, the film is fixed, and one end of the cellophane tape is peeled off in a 90 ° direction. Evaluate the power. Adhesion is evaluated according to the following criteria. Rank A: No peeling of ink layer at all (good ink adhesion) Rank B: Peeling of coating film and ink layer partially in the form of cohesive failure (somewhat good ink adhesion) Rank C: Layering between coating film and ink layer Peels off (poor ink adhesion)

[Example 1] Polyethylene terephthalate (PET) having an intrinsic viscosity (orthochlorophenol, 35 ° C) of 0.65 was melted and cast on a cooling drum. Stretched 6 times. Terephthalic acid (22
mol%), isophthalic acid (1 mol%), 2,6-naphthalenedicarboxylic acid (65 mol%), 4,4'-diphenyldicarboxylic acid (12 mol%)-ethylene glycol (75 mol%), 1,4-cyclohexanedimethanol (Tmol = 80 ° C., average molecular weight = 21,500) (A- (10 mol%), copolymerized polyester made from neopentyl glycol (15 mol%))
1) 60 wt%, polymer antistatic agent (B-1) represented by the following formula (1-2): 20 wt%, saponification degree: 86 to 89 m
% of polyvinyl alcohol (C-1) 15 wt% and polyoxyethylene lauryl ether (D-1) 5
4 g of a 10 wt% aqueous liquid having a solid content composition of
It was applied to one side of the film by a microgravure coating method with an application amount of m ² (wet). After drying, 3.6 in the horizontal direction
The film was double-stretched and heat-treated at 230 ° C. to obtain a biaxially stretched polyester film coated with an antistatic film having a thickness of 100 μm.
Table 1 summarizes the characteristics of the antistatic coating surface of this film.

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Example 2 Copolyester (A-
1) was replaced with methyl methacrylate (30 mol%), ethyl acrylate (55 mol%), acrylonitrile (10 m
ol%) and N-methylol methacrylamide (5 mol
1%) to obtain an antistatic coating-coated biaxially stretched polyester film in exactly the same manner as in Example 1, except that the acrylic copolymer (number average molecular weight: 258,000) (A-2) was prepared. . Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 3 Degree of saponification 86-89 mol%
Of polyvinyl alcohol (C-1) having a saponification degree of 76 to 8
An antistatic coating-coated biaxially oriented polyester film was obtained in exactly the same manner as in Example 2 except that the polyvinyl alcohol (C-2) was changed to 2 mol%. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 4 Degree of saponification 86 to 89 mol%
Of polyvinyl alcohol (C-1) of saponification degree 91 to 9
An antistatic coating-coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 2 except that the polyvinyl alcohol (C-3) was changed to 4 mol%. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 5 Degree of saponification 86 to 89 mol%
The polyvinyl alcohol (C-1) has a K value of 26 to 23,
Polyvinylpyrrolidone having an average molecular weight of 40,000 (C-
An antistatic coating-coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 2 except for changing to 4).
Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 6 Degree of saponification 86 to 89 mol%
Of polyvinyl alcohol (C-1) with a K value of 90 to 10
0, except that polyvinylpyrrolidone (C-5) having an average molecular weight of 1200000 was used, to obtain a biaxially stretched polyester film coated with an antistatic film in exactly the same manner as in Example 2. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 7 Degree of saponification 86-89 mol%
Of polyvinyl alcohol (C-1) having a saponification degree of 74 to 8
0 mol% of cation-modified polyvinyl alcohol (C-
Except that the procedure was changed to 6), a biaxially stretched polyester film coated with an antistatic film was obtained in exactly the same manner as in Example 2.
Table 1 summarizes the characteristics of the antistatic coating surface of this film.

[Example 8] Degree of saponification 86 to 89 mol%
Of polyvinyl alcohol (C-1) having a saponification degree of 86 to 9
1 mol% of cation-modified polyvinyl alcohol (C-
A biaxially stretched polyester film coated with an antistatic film was obtained in exactly the same manner as in Example 2 except for changing to 7).
Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 9 The solid content of the copolymer (A-1) was 25% by weight, and the acrylic copolymer (A-
2) 25 wt%, polymer antistatic agent (B-1) represented by the formula (1-2) 30 wt%, saponification degree 86 to 89 m
ol% of polyvinyl alcohol (C-1) 15 wt% and polyoxyethylene nonyl phenyl ether (D-
1) Example 1 except that the composition was changed to 5 wt%.
A biaxially stretched polyester film coated with an antistatic film was obtained in exactly the same manner as described above. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 10 Polymer antistatic agent (B-
1) is a polymer antistatic agent (B) represented by the following formula (1-3):
A biaxially stretched polyester film coated with an antistatic film was obtained in exactly the same manner as in Example 3 except that the composition was changed to -2). Table 1 summarizes the characteristics of the antistatic coating surface of this film.

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Example 11 The solid content of the copolymer (A-1) was 37 wt%, and that of the acrylic copolymer (A-
2) 36 wt%, polymer antistatic agent (B-1) represented by the above formula (1-2) 7 wt%, saponification degree 86 to 89 mo
15% by weight of 1% polyvinyl alcohol (C-1) and 5% by weight of polyoxyethylene lauryl ether (D-1)
%, And a biaxially stretched polyester film coated with an antistatic coating was obtained in exactly the same manner as in Example 1 except that the composition was changed to a composition of%. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 12 The solid content of the copolymer (A-1) was 20 wt%, and that of the acrylic copolymer (A-
2) 20 wt%, 47 wt% of the polymer antistatic agent (B-1) represented by the above formula (1-2), saponification degree 86 to 89 m
ol% of polyvinyl alcohol (C-1) 10 wt% and polyoxyethylene lauryl ether (D-1) 3w
An antistatic coating-coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 1 except that the composition was changed to t%. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 13 The solid content of the acrylic copolymer (A-2) was 61 wt%, the polymer antistatic agent (B-1) represented by the formula (1-2) was 30 wt%, and the degree of saponification was as follows. 8
6 to 89 mol% of polyvinyl alcohol (C-1) 4
wt% and polyoxyethylene lauryl ether (D-
1) Example 1 except that the composition was changed to 5 wt%.
A biaxially stretched polyester film coated with an antistatic film was obtained in exactly the same manner as described above. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 14 The solid content of the acrylic copolymer (A-2) was 42 wt%, the polymer antistatic agent (B-1) represented by the formula (1-2) was 30 wt%, and the degree of saponification was as follows. 8
6 to 89 mol% of polyvinyl alcohol (C-1) 2
3% by weight and polyoxyethylene lauryl ether (D
-1) An antistatic coating-coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 1 except that the composition was changed to 5 wt%. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Example 15 An antistatic coating-coated biaxially stretched polyester film was obtained in the same manner as in Example 3, except that polyethylene terephthalate (PET) was changed to polyethylene naphthalate (PEN). Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Comparative Example 1 The solid content was 77 wt% of the copolymerized polyester (A-1), 3 wt% of the polymer antistatic agent (B-1) represented by the formula (1-2), and the degree of saponification. 8
6 to 89 mol% of polyvinyl alcohol (C-1) 1
Except for changing to a composition consisting of 5 wt% and 5 wt% of polyoxyethylene nonylphenyl ether (D-1),
An antistatic coating-coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 1. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

[Comparative Example 2] The solid content composition was changed to methyl methacrylate (30 mol%) and ethyl acrylate (55 mol%).
%), N-methylol methacrylamide (5 mol%)
Copolymer (number average molecular weight: 26400) prepared from methacrylic acid (10 mol%) (A-3)
20 wt%, 60 wt% of the polymer antistatic agent (B-1) represented by the formula (1-2), saponification degree of 86 to 89 mol
% Of polyvinyl alcohol (C-1) 15 wt% and polyoxyethylene nonyl phenyl ether (D-1) 5
A biaxially stretched polyester film coated with an antistatic coating was obtained in exactly the same manner as in Example 1 except that the composition was changed to wt%. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

[Comparative Example 3] The solid components were changed to methyl methacrylate (30 mol%) and ethyl acrylate (55 mol%).
%), N-methylol methacrylamide (5 mol%)
Copolymer (number average molecular weight: 26400) prepared from methacrylic acid (10 mol%) (A-3)
64 wt%, 30 wt% of the polymer antistatic agent (B-1) represented by the formula (1-2), and a saponification degree of 86 to 89 mol
% Polyvinyl alcohol (C-1) 1% by weight and polyoxyethylene nonylphenyl ether (D-1) 5w
An antistatic coating-coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 1 except that the composition was changed to t%. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

[Comparative Example 4] The solid components were changed to methyl methacrylate (30 mol%) and ethyl acrylate (55 mol%).
%), N-methylol methacrylamide (5 mol%)
Copolymer (number average molecular weight: 26400) prepared from methacrylic acid (10 mol%) (A-3)
35% by weight, 30% by weight of the polymer antistatic agent (B-1) represented by the formula (1-2), and a saponification degree of 86 to 89 mol
% Of polyvinyl alcohol (C-1) 30% by weight and polyoxyethylene nonylphenyl ether (D-1) 5
A biaxially stretched polyester film coated with an antistatic coating was obtained in exactly the same manner as in Example 1 except that the composition was changed to wt%. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

[Comparative Example 5] The solid content composition was 55% by weight of the copolymerized polyester (A-1), the antistatic agent was 25% by weight of sodium polystyrene sulfonate (B-3), and polyvinyl alcohol having a saponification degree of 86 to 89 mol% ( C-1)
A biaxially oriented polyester film coated with an antistatic film was obtained in exactly the same manner as in Example 1, except that the composition was changed to 15 wt% and 5 wt% of polyoxyethylene nonylphenyl ether (D-1). Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Comparative Example 6 The solid content of the copolymer was 55% by weight of the copolymerized polyester (A-1), 25% by weight of sodium dodecylbenzenesulfonate (B-4), and the saponification degree was 86 to 8.
9mol% polyvinyl alcohol (C-1) 15wt
% And polyoxyethylene nonylphenyl ether (D
-1) An antistatic coating-coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 1 except that the composition was changed to 5 wt%. Table 1 summarizes the characteristics of the antistatic coating surface of this film.

Comparative Example 7 The properties of the biaxially stretched polyester film obtained in Example 1 without coating the composition are shown in Table 1.

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[Table 1]

[0088]

The antistatic multilayer polyester film of the present invention is superior in adhesion to water-based paints as compared with conventional ones, and has antistatic properties under low humidity, blocking resistance, backside transfer properties, and abrasion resistance. It has excellent properties and recoverability, and is useful as a plate making film, an electronic material, an OHP film, a packaging film, a label, a magnetic card (for example, a telephone card, a prepaid card) and the like.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09D 133/00 C09D 133/00 133/24 133/24 167/00 167/00 201/00 201/00 / / C08L 67:00 C08L 67:00 F-term (reference) 4F006 AA35 AB12 AB20 AB24 AB32 AB35 AB55 AB65 AB66 AB69 BA07 CA02 CA07 DA04 4F100 AH03B AH03H AH03K AK01B AK21B AK21K AK25B AK41A AK41BAK12B05B37K JG03 JK06 JL10A JL10H YY00B 4J038 CC021 CE022 CG001 CG101 CG111 CG141 CG171 CG172 CH031 CH121 CK032 CR071 DD001 DD041 GA06 GA08 GA13 KA09 MA08 MA10 NA20 PB03 PB04 PC02 4J100 AL02PHA31 BA01 HA32

Claims (8)

[Claims] 1. At least one binder resin (A) 40 selected from a copolymerized polyester resin and an acrylic copolymer on at least one surface of a polyester film.
-85% by weight, 5-50% by weight of an antistatic agent (B) containing a repeating unit having the structure represented by the following formula (1) as a main component,
An aqueous coating solution containing a composition comprising 3 to 25% by weight of a water-soluble polymer (C) and 1 to 15% by weight of a surfactant (D) is applied, and a coating film obtained by drying and stretching is applied. A laminated polyester film having antistatic properties. Embedded image (Wherein R ¹ and R ² are each H or CH ₃ , R ³
2 is an alkylene group, R ^4, R ⁵ are each a saturated hydrocarbon group having 1 to 5 carbon atoms of 2 to 10 carbon atoms, R ⁶ has a carbon number
10 to 10 alkylene groups, m is a number of 1 to 20, n is 1 to 4
The number 0 and Y ^- are a halogen ion, a mono- or poly-halogenated alkyl ion, a nitrate ion, a sulfate ion, an alkyl sulfate ion, a sulfonate ion or an alkyl sulfonate ion. ) 2. An aqueous coating liquid comprising a binder resin (A) 50 to
80% by weight, antistatic agent (B) 10 to 40% by weight, water-soluble polymer (C) 5 to 15% by weight, and surfactant (D)
2. The antistatic laminated polyester film according to claim 1, comprising a composition consisting of 3 to 10% by weight. 3. The antistatic laminated polyester film according to claim 1, wherein the water-soluble polymer (C) is polyvinyl alcohol and / or polyvinyl pyrrolidone. 4. The water-soluble polymer (C) has a saponification degree of 75 or more.
The antistatic laminated polyester film according to claim 1, which is 95 mol% of polyvinyl alcohol. 5. The antistatic laminated polyester film according to claim 1, wherein the water-soluble polymer (C) is a cation-modified polyvinyl alcohol having a saponification degree of 74 to 91 mol%. 6. The water-soluble polymer (C) having a K value of 26 to 1
The antistatic multilayer polyester film according to claim 1, which is polyvinylpyrrolidone having a molecular weight of 00 and an average molecular weight of 40,000 or more. 7. The antistatic laminated polyester film according to claim 1, wherein the polyester film is a polyethylene terephthalate film or a polyethylene-2,6-naphthalate film. 8. The polyester film has a white pigment of 5 to 5.
The antistatic laminated polyester film according to claim 1, which is a white polyester film having a thickness of 20 to 100 µm and containing 20% by weight.