JPH09314779A - Easy adhesion polyester film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a film with an excellent easy adhesiveness and destaticizing property, and an improved appearance of a coated film. SOLUTION: In this film, on at least one surface of a polyester film, an easily adhesive coating film with a thickness of 0.02-2μm is applied which is formed by applying and drying coating liquid containing a composition consisting of a 30-90wt.% binder resin (A) consisting of polyester copolymer and/or acrylic copolymer, 5-50wt.% compound (B) having sulphonic metal salt group in its molecule, and a 0.001-10wt.% fluoro-surfactant (C). agent (C).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an easy-adhesive polyester film, and more specifically, an easy-adhesive polyester film excellent in easy-adhesion property, antistatic property (antistatic property) and coating film appearance, particularly easy-adhesive white film. Regarding polyester film.

[0002]

2. Description of the Related Art Polyester film is a magnetic recording medium,
Widely used for base films such as printing materials,
As with other plastic films, static electricity is likely to occur, which causes various troubles due to static electricity during the film forming process, the processing process, or the use of the product. Further, the polyester film has a drawback that it has poor adhesion to magnetic paints and printing inks. Especially when a thick white polyester film is used for magnetic cards such as telephone cards and prepaid cards, the manufacturing process, processing steps, and the drawback that the antistatic property as the final product is insufficient,
There is a drawback that the adhesive strength to UV ink and magnetic paint is insufficient.

As a method for improving such drawbacks, a method of laminating a primer layer on a polyester film has been proposed. For example, as a method of improving the adhesiveness and antistatic property of a film, a method of forming a primer layer containing a polyester resin, an acrylic resin and a sulfonic acid or a compound containing a sulfonate group on a polyester film (Japanese Patent Publication No. No. 41655 and Japanese Patent Publication No. 6-94205) have been proposed.

However, the primer layer formed by these methods has an insufficient antistatic property under low humidity. Further, in order to exhibit good antistatic properties under low humidity, it is necessary to add an antistatic agent in a high proportion, but in this case, the wettability of the coating liquid to the polyester film is poor. Therefore, the coating property is poor, and a good coating film appearance cannot be obtained without pretreatment such as corona discharge treatment, and its application is limited.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above problems of the prior art and to manufacture the polyester film at a low processing cost because the polyester film can be favorably coated without pretreatment such as corona discharge treatment. Another object of the present invention is to provide an easily-adhesive polyester film which is excellent in coating film appearance, antistatic property and adhesiveness and which is extremely useful as a substrate for various applications.

[0006]

The object of the invention is, according to the invention, to at least one side of a polyester film,
30 to 90% by weight of a binder resin (A) composed of a polyester copolymer and / or an acrylic copolymer, and a compound (B) 5 to 50 having a metal sulfonate group in the molecule.
% By Weight and Fluorosurfactant (C) 0.001-1
This is achieved by an easily adhesive polyester film having an easily adhesive coating film having a thickness of 0.02 to 2 μm obtained by applying a coating solution containing a composition of 0% by weight and drying.
Hereinafter, the present invention will be described in detail.

[Polyester] The polyester constituting the polyester film used as the base film in the present invention is a linear polyester containing a dicarboxylic acid component and a glycol component as main components.

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. be able to. As the dicarboxylic acid component, an aromatic dicarboxylic acid is preferable from the viewpoint of mechanical properties of the film, and terephthalic acid and 2,6-naphthalenedicarboxylic acid are particularly preferable.

As the glycol component, ethylene glycol, diethylene glycol, propylene glycol,
1,3-propanediol, 1,4-butanediol,
Neopentyl glycol, 1,6-hexanediol,
Examples thereof include cyclohexanedimethanol and polyethylene glycol. Particularly, ethylene glycol is preferred from the viewpoint of the rigidity of the film.

In the present invention, when a white polyester film is used as the polyester film, the polyester preferably contains 5 to 20% by weight of a white pigment such as titanium oxide or barium sulfate. The surface glossiness of the white polyester film can be arbitrarily selected depending on the kind and the mixing ratio of the white pigment.

In addition to the above, the polyester in the present invention includes inorganic fillers such as silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, kaolin and talc, crosslinked silicone resin, crosslinked polystyrene resin, crosslinked acrylic resin, urea resin, Organic fillers made of heat-resistant polymers such as melamine resins, polyethylene, polypropylene, ethylene-propylene copolymer, other resins such as olefinic ionomers, stabilizers, antioxidants, UV absorbers, optical brighteners, etc. It can also be blended if necessary.

[Polyester Film] In the present invention, the polyester film, particularly the white polyester film, is preferably a biaxially stretched film, and its thickness is 20 μm or more, preferably 50 to 500 μm, particularly preferably 75 to 300 μm. If the thickness is less than 20 μm, the stiffness of the film may be weakened. On the other hand, if the film is too thick, for example, exceeding 500 μm, the film-forming property tends to be poor.

[Polyester Copolymer] In the present invention, a polyester copolymer and / or an acrylic copolymer is used as the binder resin (A). The polyester-based copolymer is a copolymerized polyester containing a polycarboxylic acid component and a polyol component as main components.

As the polycarboxylic acid component, terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid,
Examples thereof include adipic acid, sebacic acid, phenylindanedicarboxylic acid, dimer acid and the like. Two or more kinds of these components can be used. In addition, unsaturated polybasic acids such as maleic acid, fumaric acid and itaconic acid, and hydroxycarboxylic acids such as p-hydroxybenzoic acid and p- (β-hydroxyethoxy) benzoic acid may be used in small proportions with these components. it can. The ratio of the unsaturated polybasic acid component and the hydroxycarboxylic acid component is at most 10 mol%, preferably 5 mol% or less.

As the polyol component forming the polyester copolymer, ethylene glycol, 1,4 is used.
-Butanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol,
Xylylene glycol, dimethylolpropionic acid, glycerin, trimethylolpropane, poly (ethyleneoxy) glycol, poly (tetramethyleneoxy) glycol, and bisphenol A represented by the following formula (I)
And an propylene oxide adduct of bisphenol A represented by the following formula (II). These can use 2 or more types.

[0016]

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In the formula (I), p + q is a number of 2-10.

[0018]

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In the formula (II), r + s is a number of 2-10.

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

Further, the polyester-based copolymer includes
Some amount (20 mol% or less) to facilitate aqueous liquefaction
It is preferable to copolymerize the compound having a sulfonate group or the compound having a carboxylic acid group.

Examples of the compound having a sulfonate group include 5-Nasulfoisophthalic acid, 5-ammoniumsulfoisophthalic acid, 4-Nasulfoisophthalic acid, 4-methylammoniumsulfoisophthalic acid, 2-
Na sulfoisophthalic acid, 5-K sulfoisophthalic acid,
Preferable examples include sulfonic acid alkali metal salt-based compounds such as 4-K sulfoisophthalic acid, 2-K sulfoisophthalic acid, and Na sulfosuccinic acid, or sulfonic acid amine salt-based compounds.

Examples of the compound having a carboxylate group include trimellitic anhydride, trimellitic acid, pyromellitic anhydride, pyromellitic acid, trimesic acid, cyclobutanetetracarboxylic acid, dimethylolpropionic acid, and the like. Examples thereof include monoalkali metal salts. The free carboxyl group can be converted to a carboxylate group by reacting with an alkali metal compound or an amine compound after copolymerization.

As the polyester-based copolymer, a modified polyester copolymer, for example, a block polymer obtained by modifying a polyester copolymer with an acrylic resin, a polyurethane resin, a silicone resin, an epoxy resin, a phenol resin, or a graft polymer is used. It can also be used.

The polyester-based copolymer of the present invention 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 ethylene glycol and propylene oxide adduct of bisphenol A. Reacts with to form a monomer or oligomer,
Then, a polycondensation reaction is performed in a vacuum to obtain a copolyester having a predetermined intrinsic viscosity (preferably an intrinsic viscosity measured at 35 ° C. with o-chlorophenol of 0.2 to 0.8), and further free. It can be produced by a method of reacting a carboxy group with an alkali compound or an amine compound to form a salt. At that time, a catalyst that accelerates the reaction,
For example, esterification or transesterification catalysts, polycondensation catalysts and the like are preferably used, and various additives such as stabilizers can be added.

[Acrylic Copolymer] The acrylic copolymer in the present invention is a copolymer having an acrylic component as a constituent. As a constituent of the acrylic copolymer,
Acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, sodium acrylate, ammonium acrylate, 2-hydroxyethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, sodium methacrylate, methacrylic acid Examples thereof include ammonium, 2-hydroxyethyl methacrylate, glycidyl methacrylate, acryl methacrylate, acrylamide, methacrylamide, N-methylol methacrylamide and the like.

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, a compound having a slight amount (20 mol% or less) of a sulfonate group for facilitating aqueous liquefaction of the acrylic copolymer (sodium vinyl sulfonate, sodium methallyl sulfonate, sodium styrene sulfonate). Etc.) or a compound having a carboxylate group is preferably copolymerized.

As the acrylic copolymer, a modified acrylic copolymer, for example, a block polymer obtained by modifying an acrylic copolymer with a polyester resin, a polyurethane resin, a silicone resin, an epoxy resin, a phenol resin, or a graft polymer. Can also be used as

[Compound (B) Having a Sulfonate Metal Base in the Molecule] A compound (B) having a sulfonate metal base in the molecule in the present invention (hereinafter sometimes abbreviated as “compound (B)”) Is a conventionally known low molecular weight compound or polymer compound having a sulfonic acid metal base in the molecule (however, a polymer having a sulfonic acid metal base in the molecule as a component of 50 mol% or more). Alkyl sulfonic acid metal salt, alkyl benzene sulfonic acid metal salt, alkyl diphenyl ether disulfonic acid metal salt, vinyl copolymer having a sulfonic acid metal base (for example, polystyrene copolymer having 50 mol% or more of a component having a sulfonic acid metal base), etc. Examples of the metal include Li, Na, K and the like. These compounds (B) can be used alone or in combination.

[Fluorosurfactant (C)] The fluorosurfactant (C) in the present invention is a surfactant having a fluorine element in the molecule, for example, the following formulas (III) to (IX). The compound shown by can be mentioned.

[0032]

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In the formula (III), n is a number from 1 to 12 and m is 1 to
The number of 30, R ¹ is a hydrocarbon group having 1 to 10 carbon atoms or a phenyl group.

[0034]

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In the formula (IV), n is a number from ^{1 to} 12 and M ¹ is an alkali metal or NH ₄ group.

[0036]

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In the formula (V), n is a number of 1 to 12, M ² is an alkali metal, and R ¹ is a hydrocarbon group having 1 to 10 carbon atoms or a phenyl group.

[0038]

[Chemical 6]

In the formula (VI), n is a number from 1 to 12 and t is 1 to
The number of 10, R ¹ is a hydrocarbon group having 1 to 10 carbon atoms or a phenyl group, and R ² is a H or NH ₄ group.

[0040]

[Chemical 7]

In the formula (VII), n is a number from 1 to 12 and u is 1 to
Number of 6, X is a halogen atom, R ³ is H, and has 1 to 10 carbon atoms.
Is a hydrocarbon group or a phenyl group.

[0042]

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In the formula (VIII), n is a number from ^{1 to} 12 and M ¹ is an alkali metal or NH ₄ group.

[0044]

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In the formula (IX), n is a number from 1 to 12 and u is 1 to
The number 6, R ¹ is a hydrocarbon group having 1 to 10 carbon atoms or a phenyl group.

These fluorine-containing surfactants (C) can be used alone or in combination.

Among the above compounds, the compound represented by the above formula (III) can be mentioned as a particularly preferable fluorine-containing surfactant (C). In the compounds represented by the above formulas (III) to (IX), r is preferably 4 to 12,
From the viewpoint of coatability, r is more preferably 6-10. As s, 1 to 30 is preferable, and from the viewpoint of coatability, s is more preferably 3 to 15. Further, R ¹ is preferably a hydrocarbon group having 1 to 10 carbon atoms, and more preferably a hydrocarbon group having 2 to 7 carbon atoms from the viewpoint of coatability.

[Composition] In the present invention, the binder resin (A) is provided on at least one surface of the polyester film.
Easy adhesion obtained by applying a coating solution containing a composition of 30 to 90% by weight, 5 to 50% by weight of the compound (B) and 0.001 to 10% by weight of a fluorosurfactant (C) and drying. A protective coating.

In the above composition, the proportion of binder resin (A) is 30 to 90% by weight, but 40 to 80.
It is preferably in the weight%. If the proportion of the binder resin (A) is less than 30% by weight, the adhesion of the easily adhesive coating film to the polyester film will be insufficient. On the other hand, if the proportion of the binder resin (A) exceeds 90% by weight, the blocking resistance of the film provided with the easily adhesive coating becomes poor.

In the above composition, the compound (B)
Is 5 to 50% by weight, preferably 10 to 40% by weight. When the proportion of the compound (B) is less than 5% by weight, the antistatic property to the film is insufficient. On the other hand, when the proportion of the compound (B) exceeds 50% by weight, the adhesion of the easily adhesive coating film to the polyester film becomes insufficient.

In the above composition, the proportion of the fluorosurfactant (C) is 0.001 to 10% by weight, preferably 0.005 to 8% by weight, particularly 0.01 to 10% by weight. It is preferably 6% by weight. If the proportion of the fluorinated surfactant (C) is less than 0.001% by weight, the effect of improving the coatability of the coating liquid cannot be obtained. On the other hand, if the proportion of the fluorosurfactant (C) exceeds 10% by weight, the adhesion of the easily adhesive coating film to the polyester film will be insufficient and the adhesion to ink or paint will be insufficient.

[Coating Liquid] The coating liquid in the present invention is preferably an aqueous coating agent (using water as a medium), but it is also possible to use an organic solvent as a solvent. Examples of this organic solvent include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexanone, n-hexane, toluene, xylene, methanol, ethanol, n-propanol, isopropanol and the like. These may be used alone or in combination of two or more.

The coating solution of the present invention, particularly the aqueous coating solution, comprises
It is preferable to add a wetting agent in order to improve the wettability to the polyester film. The wetting agent may be an interface of an anionic surfactant, a cationic surfactant, a nonionic surfactant, etc., which makes the surface tension of the coating liquid, particularly the aqueous coating liquid, 50 dyne / cm or less, preferably 40 dyne / cm or less. Activators are preferred, such as polyethylene oxide / polypropylene oxide block copolymers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene-fatty acid esters, sorbitan fatty acid esters, glycerin fatty acid esters, aliphatic metal soaps, alkyl sulfates, quaternary Examples thereof include ammonium chloride salt, quaternary ammonium sulfate ethyl salt, and alkylamine hydrochloride. The amount of the wetting agent is preferably 2 to 30% by weight of the total solid content in the coating liquid, more preferably 3 to
It is 20% by weight.

Further, additives such as ultraviolet absorbers, pigments, lubricants, antiblocking agents, crosslinking agents such as melamine, epoxy, aziridine and other antistatic agents are added to the coating liquid within the range not impairing the object of the present invention. Can be blended.

The solid content concentration in the coating liquid in the present invention is usually preferably 0.5 to 30% by weight.

[Coating of easily-adhesive coating film] In the present invention, a coating solution containing the above-mentioned composition is coated on at least one side of a polyester film. As this film, a polyester film before completion of crystal orientation is used. preferable. As the polyester film before completion of the oriented crystals, an unstretched film obtained by heat-melting polyester to be a film as it is, a uniaxially stretched film obtained by orienting the unstretched film in either the longitudinal direction or the transverse direction. ,
An example is one that has been stretched and oriented in a low-magnification direction in both the machine direction and the transverse direction (a biaxially stretched film before being finally re-stretched in the machine direction and the transverse direction to complete the oriented crystallization). .

As a method for applying the coating agent to the polyester film, any known coating method can be applied. For example, a roll coating method, a gravure coating method, a microgravure coating method, a reverse coating method, a roll brushing method, a spray coating method, an air knife coating method, an impregnation method, a curtain coating method, or the like may be applied alone or in combination. When an aqueous coating is used, a small amount of an organic solvent may be included for the purpose of assisting the stability of the coating.

The coating amount of the coating liquid is 1 m of the running film.
^{2 to} 50 g, and more preferably 3 to 40 g per ² are preferable. The final dry coating film (easy-adhesive coating film) has a thickness of 0.02.
˜2 μm is necessary, and preferably 0.05 to 1 μm. If the thickness of the coating film is less than 0.02 μm, the antistatic property becomes insufficient, and if it exceeds 2 μm, the slip property is deteriorated, which is not preferable. The coating can be carried out on only one side or on both sides depending on the intended use of the film. After coating, the coating is dried to form a uniform coating.

In the present invention, after applying the coating liquid to the polyester film, it is dried, preferably stretched. This drying is preferably carried out at 90 to 130 ° C. for 2 to 20 seconds. This drying can also serve as a preheat treatment for the stretching treatment or a heat treatment during the stretching. The polyester film is stretched at a temperature of 70 to 140 ° C. in the longitudinal direction of 2.5.
~ 7 times, 2.5 to 7 times in the lateral direction, 8 times or more in area magnification,
Furthermore, it is preferable to stretch 9 to 28 times. In the case of re-stretching, it is preferable to stretch at a ratio of 1.05 to 3 times (however, the area magnification is the same as above). The heat setting after the stretching is preferably performed at a temperature higher than the final stretching temperature and lower than the melting point for 1 to 30 seconds. For example, for a polyethylene terephthalate film, it is preferable to heat-fix at 170 to 240 ° C. for 2 to 30 seconds.

[Magnetic Recording Layer] In the easily adhesive polyester film of the present invention, a magnetic recording layer can be provided on at least a part of the easily adhesive coating film. The magnetic recording layer is not particularly limited, but the following can be mentioned as typical examples. That is, as magnetic powder, for example, γ-F
_{e 2 O 3, CrO 2 Co} -γ-Fe 2 O 3, Fe
₃ O ₄ , BaO · 6FeO ₃ , metal magnetic powder, etc. are used,
As the binder, for example, vinyl resin such as vinyl acetate, polyvinylidene chloride and PVC, acrylic resin, rubber resin such as acrylonitrile / butadiene copolymer, cellulose resin such as nitrocellulose, epoxy resin, phenol resin, polyurethane. Examples include a mixture of a system resin and the like, and if necessary, a dispersant, a lubricant, a stabilizer, an antistatic agent such as carbon, and a plasticizer.

[Printing Ink Layer] In the easily adhesive polyester film of the present invention, a printing ink layer can be provided on at least a part of the easily adhesive coating film. The printing ink layer is not particularly limited, but conventionally known UV-curable printing ink, electron beam-curable ink, heat-sensitive recording ink and the like can be used.

Hereinafter, the present invention will be specifically described 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.

[0063]

The present invention will be described in more detail with reference to the following examples. The characteristics of the film were measured by the methods described below. Moreover, an average molecular weight shows a number average molecular weight.

1. Magnetic paint adhesion The following paints for evaluation (magnetic paints) are applied to the coating surface of the film by means of a Mayer bar so that the thickness after drying is about 4 μm, and dried at 100 ° C. for 3 minutes to obtain magnetic paints. Apply coating. After that, aging was performed at 60 ° C. for 24 hours, and then Scotch tape No. 600 (3M) width 12.
Adhere 7mm, length 15cm so that air bubbles do not enter,
This is leveled and brought into close contact with a manual load roll described in JIS C2701 (1975), and cut into a tape width. The strength when the coating film of this sample and the magnetic coating film were peeled off by 180 ° was measured and used as the magnetic coating adhesive force. Paint for evaluation: Urethane resin Nipporan 2304 (manufactured by Nippon Polyurethane) 25 parts PVC / vinyl acetate resin S-REC A (manufactured by Sekisui Chemical) 50 parts Dispersant Resion P (manufactured by Riken Vitamin) 1 part Magnetic agent CTX-860 (Manufactured by Toda Kagaku Co., Ltd.) 500 parts is dissolved in a mixed solvent of methyl ethyl ketone / toluene / cyclohexanone to obtain a 40% solution, which is then dispersed in a sand grinder for 2 hours. Thereafter, 25 parts (in terms of solid content) of coronate L as a cross-linking agent are added and stirred well to obtain a magnetic paint.

2. UV ink adhesive strength A 250 μm-thick polyester film is attached to the uncoated surface of the sample with an adhesive for reinforcement. Then, an ultraviolet-curable printing ink (Flash Dry FDO Red APN made by Toyo Ink) was printed on the surface of the sample coated with a coating film by an RI tester (manufactured by Mei Seisakusho), and then a medium pressure mercury lamp (80
W / cm, single-light type; made by Nippon Battery Co., Ltd.) Curing is performed with a UV curing device to form a UV ink layer having a thickness of 3.0 μm. Cellophane tape (18 mm width; on this UV ink layer;
Nichiban) 15cm long, and 2kg on top
A fixed load was applied by a manual load roll of No. 1 to fix the film, and one end of the cellophane tape was peeled in the 90 ° direction. From the peeling condition, the UV ink adhesive strength was evaluated according to the following five-stage criteria. 5: The ink layer does not peel at all ... UV ink adhesion is extremely good 4: Less than 3% of the ink layer peels off ... UV ink adhesion is good 3: 3-10% of the ink layer peels off ... UV ink adhesion is somewhat Good 2-10 to 30% of the ink layer peels off ... UV ink adhesion is somewhat poor 1: 30% or more of the ink layer peels off ... UV ink adhesion is poor

3. Specific surface resistance: Takeda Riken specific resistance measuring device
An applied voltage of 500 V was applied to the film sample under conditions of ℃ and measured humidity of 40%, and the surface specific resistance value (Ω /
□) was measured and the antistatic property was evaluated according to the following criteria. Surface resistivity is less than 1 × 10 ¹³ Ω / □ …… Good antistatic property Surface resistivity exceeds 1 × 10 ¹³ Ω / □ …… Poor antistatic property

4. Appearance of coating film The appearance of the coating film of the film was observed and evaluated according to the following criteria. ◯: The coating film has a uniform appearance. ... Good appearance of coating film x: A portion having a non-uniform appearance is observed on the coating film. ...... Poor coating film appearance

Example 1 90% by weight of polyethylene terephthalate having an intrinsic viscosity of 0.65 dl / g and titanium oxide 10
A composition consisting of wt% was melted by an extruder, cast on a cooling drum to obtain an unstretched film, and then stretched 3.6 times in the machine direction to obtain a uniaxially stretched film. The terephthalic acid (11
Mol%), isophthalic acid (1 mol%), 2,6-naphthalenedicarboxylic acid (69 mol%), 4,4′-diphenyldicarboxylic acid (9 mol%) and 5-Ksulfoisophthalic acid (10 mol%) , Ethylene glycol (73 mol%) as a glycol component, 1,4-cyclohexanedimethanol (12 mol%) and a propylene oxide adduct of bisphenol A with p = 1 and q = 1 in the formula (II) (15 mol%). Copolyester A-1 (Tg = 80 ° C., average molecular weight = 20,5)
00) 65% by weight, 25% by weight of sodium dodecylbenzenesulfonate as an antistatic agent, and r = 8, s = 10, R ¹ = in the above formula (III) as a fluorosurfactant.
A 10% by weight aqueous solution having a composition of 5% by weight of C ₃ H ₇ compound (C-1) and 5% by weight of polyoxyethylene nonylphenyl ether was applied to the microgravure coating method at a coating amount of 4 g / m ² (wet). Applied. Furthermore, after drying this coated film, it was stretched in the transverse direction by a factor of 3.6 to give 230
A biaxially stretched polyester film having a thickness of 188 μm and having a coating film applied was heat-treated at ° C. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

Example 2 Instead of the copolymerized polyester A-1, methyl methacrylate, ethyl acrylate, 2
Acrylic Copolymer A Made from -Hydroxyethyl Methacrylate and N-Methylol Methacrylamide
-2 (number average molecular weight: 248000) was used to obtain a biaxially stretched polyester film coated with a coating film in the same manner as in Example 1. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

Example 3 Copolyester A-1
(30% by weight), acrylic copolymer A-2 (30% by weight), sodium polystyrenesulfonate (30% by weight) as an antistatic agent, compound (C-1) (5% by weight) as a fluorine-based surfactant. A biaxially stretched polyester film coated with a coating film was obtained in the same manner as in Example 1 except that an aqueous liquid having a composition consisting of and polyoxyethylene nonylphenyl ether (5% by weight) was used. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

[Example 4] A coating film was applied in the same manner as in Example 3 except that an acrylic polymer made of methyl methacrylate, butyl acrylate and sodium methallylsulfonate was used as an antistatic agent. The obtained biaxially stretched polyester film was obtained. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

Example 5 Copolyester A-1
(32.99% by weight), acrylic copolymer A-2 (32
%), Sodium polystyrene sulfonate (30% by weight) as an antistatic agent, compound (C-1) (0.01% by weight) as a fluorosurfactant and polyoxyethylene nonylphenyl ether (5% by weight). A biaxially stretched polyester film coated with a coating film was obtained in the same manner as in Example 1 except that an aqueous liquid having the following composition was used. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

Example 6 Copolyester A-1
(28% by weight), acrylic copolymer A-2 (27% by weight), sodium polystyrenesulfonate (30% by weight) as an antistatic agent, compound (C-1) (10% by weight) as a fluorine-based surfactant. A biaxially stretched polyester film coated with a coating film was obtained in the same manner as in Example 1 except that an aqueous liquid having a composition consisting of and polyoxyethylene nonylphenyl ether (5% by weight) was used. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

Example 7 In the same manner as in Example 3 except that the fluorine-based surfactant was changed to the compound (C-2) where r = 8 and M was K (potassium) in the above formula (IV). A biaxially stretched polyester film coated with a coating film was obtained. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

[Embodiment 8] A fluorine-based surfactant was used in the above formula (V) in which r = 8, M was Na (sodium) and R
^A biaxially stretched polyester film coated with a coating film was obtained in the same manner as in Example 3 except that 1 was changed to the compound (C-3) having C ₃ H ₇ . Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

Comparative Example 1 Copolyester A-1
(70% by weight), as an antistatic agent, sodium dodecylbenzenesulfonate (25% by weight) and polyoxyethylene nonylphenyl ether (5% by weight) were used. A biaxially stretched polyester film coated with a coating film was obtained. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

[Comparative Example 2] Acrylic copolymer A-2 (7)
0% by weight), as an antistatic agent, sodium dodecylbenzenesulfonate (25% by weight) and polyoxyethylene nonylphenyl ether (5% by weight). A biaxially stretched polyester film coated with a film was obtained. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

Comparative Example 3 Copolyester A-1
(33% by weight), acrylic copolymer A-2 (32% by weight), sodium polystyrenesulfonate (30% by weight) as an antistatic agent, and polyoxyethylene nonylphenyl ether (5% by weight). A biaxially stretched polyester film coated with a coating film was obtained in the same manner as in Example 1 except that was used. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

Comparative Example 4 Copolyester A-1
(32.9992% by weight), acrylic copolymer A-2
(32% by weight), sodium polystyrene sulfonate (30% by weight) as an antistatic agent, compound (C-1) (0.0008% by weight) as a fluorosurfactant and polyoxyethylene nonylphenyl ether (5% by weight). A biaxially stretched polyester film coated with a coating film was obtained in the same manner as in Example 1 except that the aqueous liquid having the composition (1) was used. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

[Comparative Example 5] Copolyester A-1
(25% by weight), acrylic copolymer A-2 (25% by weight), sodium polystyrenesulfonate (30% by weight) as an antistatic agent, compound (C-1) (15% by weight) as a fluorine-based surfactant. A biaxially stretched polyester film coated with a coating film was obtained in the same manner as in Example 1 except that an aqueous liquid having a composition consisting of and polyoxyethylene nonylphenyl ether (5% by weight) was used. Table 1 shows the coating film appearance, magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

[Comparative Example 6] A biaxially stretched polyester film was obtained in the same manner as in Example 1 except that no coating film was applied. Table 1 shows the magnetic paint adhesion, UV ink adhesion and surface resistivity measurement results of this film.

[0082]

[Table 1]

As is clear from the results shown in Table 1, the easily adhesive polyester film of the present invention was excellent in coating film appearance, magnetic coating adhesive strength, UV ink adhesive strength and antistatic property.

[0084]

The easily-adhesive polyester film according to the present invention is superior in adhesiveness to magnetic paint, UV ink adhesiveness and antistatic property as compared with the conventional ones, and the appearance of the coating film is particularly good. Cards, magnetic disks, printing materials,
It is useful for graphic materials and photosensitive materials.

Claims (4)

[Claims] 1. A binder resin (A) comprising a polyester-based copolymer and / or an acrylic-based copolymer in an amount of 30 to 90% by weight on at least one side of a polyester film,
Compound (B) having a sulfonic acid metal base in the molecule
50% by weight and fluorine-based surfactant (C) 0.001
An easily-adhesive polyester film provided with an easily-adhesive coating film having a thickness of 0.02 to 2 μm obtained by applying a coating solution containing a composition of 10% by weight and drying the composition. 2. The polyester film contains a white pigment in an amount of 5 to 5.
The easily adhesive polyester film according to claim 1, which is a white film containing 20% by weight and having a thickness of 20 μm or more. 3. The easily adhesive polyester film according to claim 1, wherein the coating liquid is an aqueous coating liquid. 4. The easily-adhesive polyester film according to claim 2, wherein a magnetic recording layer and / or a printing ink layer is provided on at least a part of the easily-adhesive coating film.