JPH09239934A - Easy adhesion polyester film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an easily adhesive polyester film having excellent easy adhesiveness and antistatic property, and improved abrasion resistance in a coated film. SOLUTION: An easily adhesive skin film having a thickness of a dried skin film of 0.02-2μm is applied on at least one surface of an aromatic polyester film in use of a coating agent containing a composition consisting of a kind of 30-90wt.% of binder selected from copolymeric polyester resin (1), 3-50wt.% of substance having sulfonic acid base contained in its molecule (2), and 0.5-30wt.% of interfacial active agent having a flow point of -50 to 10 deg.C and a hazing point of 30 deg.C or higher (3).

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 and abrasion resistance of a coating film, particularly an easy-adhesive white polyester film. Regarding

[0002]

2. Description of the Related Art Aromatic polyester films are widely used as base films for magnetic recording media, printing materials, etc. However, static electricity is liable to occur as a common problem with plastic films, and film formation processes, processing processes, and product There are drawbacks in that various problems occur during use and the adhesiveness of magnetic paints and printing inks is poor.

Thick white polyester films are used for magnetic cards such as telephone cards and prepaid cards. The manufacturing process, processing process, antistatic property of the final product, UV ink and magnetic paint are used. Adhesion is difficult, and application of a primer has been proposed.

Conventionally, as a method of improving the adhesiveness and antistatic property of a film, a method of coating a polyester resin, an acrylic resin, and a primer layer containing a sulfonate group or a compound having a sulfonate group as a constituent component. Are proposed in Japanese Examined Patent Publication No. 5-41655 and Japanese Examined Patent Publication No. 6-94205.

However, the primer layer formed by these methods has an antistatic property, but has insufficient adhesion to the ink layer. Further, according to the research conducted by the present inventor, a compound having a sulfonic acid group or a sulfonate group causes brittleness of a coating film, resulting in a defect that the abrasion resistance of the coating film is insufficient.

On the other hand, as a method for improving the slipperiness, blocking property and abrasion resistance, a method of incorporating a filler (fine particles) in the primer layer has been proposed in Japanese Patent Laid-Open No. 3-26543.

However, the primer layer formed by this method has a drawback that other properties such as adhesiveness are impaired.

[0008]

DISCLOSURE OF THE INVENTION As a result of further studies to improve this problem, the present inventors have found that by using a specific surfactant in the primer layer in combination, a coating film can be obtained without impairing other properties. The inventors have found that the wear resistance of the can be greatly improved and have reached the present invention.

[0009]

Means for Solving the Problems That is, the present invention, on at least one surface of the aromatic polyester film, (1) at least one binder selected from copolymerized polyester resin and acrylic copolymer 30 to 90 wt%, (2) 3-50% by weight of a substance having a sulfonate group in the molecule and (3)
Using a coating composition containing 0.5 to 30% by weight of a surfactant having a pour point of −50 to 10 ° C. and a cloud point of 30 ° C. or higher,
An easily-adhesive polyester film with improved abrasion resistance, characterized in that an easily-adhesive film having a dry film thickness of 0.02 to 2 μm is applied.

In the present invention, the aromatic polyester means
It is a crystalline linear saturated polyester synthesized from an aromatic dibasic acid or its ester-forming derivative and a diol or its ester-forming derivative. As a specific example of this polyester, polyethylene terephthalate,
Examples thereof include polyethylene isophthalate, polybutylene terephthalate, poly (1,4-cyclohexylene dimethylene terephthalate), and polyethylene-2,6-naphthalene dicarboxylate. These include copolymers and blends of these with small proportions of other resins. Among these, polyethylene terephthalate and polyethylene-2,6-naphthalene dicarboxylate are particularly preferable.

The aromatic polyester preferably contains a white pigment such as titanium oxide and / or barium sulfate. In addition, from inorganic fillers such as silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, kaolin, talc, etc., heat-resistant resins such as crosslinked silicone resin, crosslinked polystyrene resin, crosslinked acrylic resin, urea resin, melamine resin, etc. Other organic fillers such as polyethylene, polypropylene, ethylene / propylene terpolymers, olefinic ionomers, stabilizers, antioxidants, ultraviolet absorbers, optical brighteners, etc. may be contained as required. .

The white polyester film in the present invention contains, for example, 5 to 2 white pigments such as titanium oxide and barium sulfate.
It contains 0% by weight, and its surface glossiness can be arbitrarily selected as desired.

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 μm.
˜500 μm, particularly preferably 75 to 300 μm. If the thickness is less than 20 μm, the film becomes softer. On the other hand, if the film is too thick, for example, exceeding 500 μm, the film-forming property tends to deteriorate.

In the present invention, the primer layer (easy-adhesive coating) provided on at least one side of the polyester film is (1) at least one binder selected from copolymerized polyester resin and acrylic copolymer 30 to 90
% By weight, (2) substance having sulfonate group in molecule 3 to 50
% And (3) a pour point of −50 to 10 ° C. and a cloud point of 30 to 30 ° C. A coating composition containing 0.5 to 30% by weight of a surfactant is applied to the required surface of the film. It is formed by drying.

Binder constituting the coating material in the present invention
Acid components forming the copolymerized polyester resin (1) include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, adipic acid, sebacic acid, phenylindanedicarboxylic acid Acids, dimer acids and the like can be exemplified.
Two or more kinds of these components can be used. Further, together with these components, unsaturated polybasic acids such as maleic acid, fumaric acid and itaconic acid, p-hydroxybenzoic acid, p
A small proportion of hydroxycarboxylic acid such as-(β-hydroxyethoxy) benzoic acid can be used. The ratio of unsaturated polybasic acid components and hydroxycarboxylic acid components is at most 10
It is mol%, preferably 5 mol% or less.

The polyol component for forming the copolyester resin is ethylene glycol, 1,4
-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 ethylene oxide adducts and propylene oxide adducts of bisphenol A represented by the following formula

[0017]

Embedded image

[0018]

Embedded image

[However, n + m = 2 to 10, ph = phenylene group] and the like can be exemplified. Two or more of these can be used.

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

Further, the copolymerized polyester resin may be copolymerized with a compound having a slight amount of a sulfonate group or a compound having a carboxylic acid group in order to facilitate liquefaction in water. Is preferred.

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 thereof include alkali metal sulfonic acid salts such as 4-K sulfoisophthalic acid, 2-K sulfoisophthalic acid, and sodium sulfosuccinic acid, and amine sulfonate compounds.

Examples of the compound having a carboxylic acid group include trimellitic anhydride, trimellitic acid, pyromellitic dianhydride, pyromellitic acid, trimesic acid, cyclobutanetetracarboxylic acid, dimethylolpropionic acid, and the like, or monos thereof. Examples thereof include alkali metal salts. After the copolymerization, the free carboxyl group is reacted with an alkali metal compound or an amine compound to form a carboxylate group.

Further, as the copolymerized polyester resin, a modified polyester copolymer, for example, the polyester copolymer described above may be used in the form of acryl, polyurethane, silicone, epoxy,
It is also possible to use a block polymer modified with a phenol resin or the like, or a graft polymer.

The copolymerized polyester resin in the present invention can be produced by the conventionally known or used polyester production techniques. For example, terephthalic acid or its ester-forming derivative (especially dimethyl ester), isophthalic acid or its ester-forming derivative (especially dimethyl ester) and trimellitic anhydride are reacted with ethylene glycol and a propylene oxide adduct of bisphenol A to form a monomer. Alternatively, a copolymerized polyester having a predetermined intrinsic viscosity (preferably an intrinsic viscosity measured at 35 ° C. with o-chlorophenol of 0.2 to 0.8) is formed by forming an oligomer and then subjecting it to polycondensation reaction under vacuum. It can be produced by a method in which a free carboxyl group is reacted with an alkali compound or an amine compound to form a salt. In that case, it is preferable to use a catalyst that accelerates 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.

Binder constituting the coating material in the present invention
The constituent components of the acrylic copolymer (1) include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, sodium acrylate, ammonium acrylate, 2-hydroxyethyl acrylate, methacrylic acid, and methyl methacrylate. , Ethyl methacrylate, butyl methacrylate, sodium methacrylate, ammonium methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate, sodium vinyl sulfonate,
Examples thereof include sodium methallyl sulfonate, sodium styrene sulfonate, acrylamide, methacrylamide, N-methylol methacrylamide, and N-methylol acrylamide. These monomers are
For example, it can be used in combination with other unsaturated monomers such as styrene, vinyl acetate, acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, and divinylbenzene.

As the acrylic copolymer, a modified acrylic copolymer, for example, a block polymer obtained by modifying the above acrylic copolymer with polyester, polyurethane, silicone, epoxy, phenol resin or the like, or a graft polymer may also be used. it can.

In the present invention, the substance (2) having a metal sulfonate group in the molecule constituting the coating agent is a conventionally known low molecular weight substance or polymer substance having a metal sulfonate group in the molecule, for example, Alkyl sulfonic acid metal salt, alkyl benzene sulfonic acid metal salt, alkyl diphenyl ether disulfonic acid metal salt, acrylic copolymer having a sulfonic acid metal base, polyester copolymer, vinyl copolymer (eg polystyrene copolymer) and the like. . These may be used alone or in combination of two or more.

Surfactant that constitutes the coating liquid in the present invention
(3) is a surfactant having a pour point of −50 to 10 ° C. and a cloud point of 30 ° C. or higher. Here, the pour point is defined by Japanese Industrial Standards (JISK2269-1987), and is obtained using an automatic pour point cloud point measuring device (manufactured by Estee M Co., Ltd.). The cloud point (cloud point) is the temperature at which a 2% by weight aqueous solution of a sample becomes cloudy by heating and turbidity in a test tube, and then gradually cooled to make the aqueous solution transparent. The FP81HT cloud point automatic Measuring device and FP9
0 controller (manufactured by Nihon Siber Hegner Co., Ltd.).

The cloud point occurs only for nonionic surfactants. Therefore, the surfactant (3) is composed of a nonionic surfactant.

Examples of the surfactant (3) include polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxypropylene alkyl ether, polyoxypropylene alkylphenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkyl. Phenyl ester, polyoxypropylene alkyl ester, polyoxypropylene alkylphenyl ester, polyoxyethylene phenyl ether, polyoxypropylene phenyl ether, poly (oxyethylene / oxypropylene) alkyl ether, poly (oxyethylene / oxypropylene) alkylphenyl ether , Polyethylene oxide / polypropylene oxide block copolymer, polyoxyethylene-fatty acid ester Le, sorbitan fatty acid esters,
Examples thereof include glycerin fatty acid ester. Among these, poly (oxyethylene / oxypropylene) alkyl ether, poly (oxyethylene / oxypropylene) alkylphenyl ether, and polyethylene oxide / polypropylene oxide block copolymer are preferable, and poly (oxyethylene / oxypropylene) alkyl ether, Particularly preferred is poly (oxyethylene / oxypropylene) alkyl phenyl ether.

The pour point of this surfactant must be from -50 to 10 ° C, preferably from -30 to 5 ° C. If the pour point is below -50 ° C, the stability of the coating will be insufficient, while at 10 ° C
If it exceeds, the abrasion resistance of the coating film is insufficient. The cloud point is 30.
℃ or more, preferably 50 ℃ or more,
More preferably, it is 80 ° C or higher. If the cloud point is less than 30 ° C, the stability of the coating will be insufficient.

The coating composition of the present invention, especially the aqueous liquid, may be combined with other surfactants in order to improve the wettability to the aromatic polyester film as long as the object of the present invention is not impaired. The surface tension of the coating is 50 dy
Ne / cm or less, preferably 40 dyne / cm or less is preferable.

In the present invention, a copolyester resin
(1) and at least one binder selected from the acrylic copolymer (1), a substance (2) having a sulfonate metal base in the molecule, and a binder (1) per composition consisting of a surfactant (3) The proportion of 30 to 90% by weight, preferably 40 to 80
% By weight. If this proportion is less than 30% by weight, the adhesion of the primer layer to the polyester film becomes insufficient, which is not preferable. On the other hand, if it exceeds 90% by weight, the blocking property of the coated film deteriorates, which is not preferable.

The ratio of the substance (2) having a metal sulfonate group in the molecule is 3 to 50% by weight, preferably 10 to 40% by weight.
It is. If this ratio is less than 3% by weight, the antistatic property is insufficient, while if it exceeds 50% by weight, the adhesion of the primer layer to the polyester film is insufficient, which is not preferable.

The ratio of the surfactant (3) is 0.5 to 30% by weight, preferably 1 to 20% by weight. If this ratio is less than 0.5% by weight, the abrasion resistance of the primer layer may be insufficient, while if it exceeds 30% by weight, the blocking property of the coated film may be deteriorated or the adhesive strength to ink or paint may be insufficient. Not preferable.

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

Further, as long as the object of the present invention is not impaired, a UV absorber, a pigment, a lubricant, an antiblocking agent, a crosslinking agent such as melamine, epoxy, aziridine, and other additives such as other antistatic agents are mixed. can do.

The solid content concentration of the coating material in the present invention is 0.5
It is preferably about 30% by weight.

In the present invention, a (primer) coating agent containing each of the above-mentioned components is applied to at least one side of a polyester film, which is preferably a polyester film before completion of crystal orientation.

As the polyester film before completion of the crystal orientation, an unstretched film obtained by heat-melting polyester to form a film as it is, or the unstretched film was oriented in either the longitudinal direction or the transverse direction. Examples include a uniaxially stretched film, and a low-stretch stretched and oriented film in both the longitudinal and transverse directions (a biaxially stretched film before it is finally re-stretched in the longitudinal or transverse direction to complete the oriented crystallization). can do.

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 contained for the purpose of assisting the stability of the coating or the coating property of the coating. The coating amount is 1 m ² of running film
It is preferably 3 to 50 g, more preferably 5 to 40 g. The thickness of the final dry coating film (coating) is required to be 0.02 to 2 μm, preferably 0.05 to 1 μm. Coating thickness is 0.02
If it is less than μm, the antistatic property becomes insufficient, while the other 2
When it exceeds μm, the slipperiness is deteriorated, which is not preferable.

The coating can be carried out on one side only 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, the polyester film is coated with the coating agent and then dried, preferably stretched, and 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
It is preferable to stretch at 70 to 140 ° C. in the longitudinal direction of 2.5 to 7 times, in the transverse direction of 2.5 to 7 times, and in area magnification of 8 times or more, and further 9 to 32 times. 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 after stretching is at a temperature higher than the final stretching temperature and below the melting point.
It is preferable to carry out for 1 to 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 magnetic recording layer in the present invention is not particularly limited, but the following can be mentioned as typical examples. That is, as the magnetic powder, for example, γ-Fe ₂ O ₃ , C
rO ₂ , Co-γ-Fe ₂ O ₃ , Fe ₃ O ₄ , BaO · 6F
eO ₃ , metal magnetic powder, etc., and as a binder,
For example, polyvinyl acetate, polyvinylidene chloride, vinyl resin such as PVC, acrylic resin, rubber resin such as acrylonitrile / butadiene copolymer, cellulose resin such as nitrocellulose, epoxy resin, phenol resin, polyurethane resin, etc. And a mixture of these and a dispersant, a lubricant, a stabilizer, an antistatic agent such as carbon, and a plasticizer, which are added as necessary.

The printing ink layer in the present invention is not particularly limited, but conventionally known ultraviolet curing type printing ink, electron beam curing type ink, heat sensitive recording type ink and the like can be used.

[0048]

EXAMPLES The present invention will be further described below with reference to examples. The characteristics in the examples were obtained by the following method.

1. Adhesive strength of magnetic paint The following evaluation paint was applied to the sample film with a Meyer bar so that the thickness after drying would be about 4 μm, and the film was dried at 100 ° C for 3 days.
Dry for minutes. After that, it was aged at 60 ° C for 24 hours, and then a Scotch tape No. 600 (3M) with a width of 12.7 mm and a length of 15 cm was adhered to it so that no bubbles could enter it.
Using a manual load roll described in SC2701 (1975), the film is leveled and brought into close contact and cut into a tape width. The strength when peeled 180 degrees is measured.

[Evaluation paint] 25 parts by weight of urethane resin Nipporan 2304 (manufactured by Nippon Polyurethane), 50 parts by weight of vinyl chloride / vinyl acetate resin S-REC A (manufactured by Sekisui Chemical Co., Ltd.), dispersant Recion P (manufactured by Riken Vitamin) in terms of solid content ) 1 part by weight and magnetic powder CTX-860 (manufactured by Toda Kagaku) 50
0 part by weight is mixed with a mixed solvent of methyl ethyl ketone / toluene / cyclohexanone to obtain a 40% liquid, which is dispersed for 2 hours by a sand grinder. Then the crosslinking agent Coronate L
Add 25 parts by weight (as solid content) and stir well to obtain a magnetic paint.

2. Adhesive strength of UV ink A UV curable printing ink (Flash Dry FD Carton P Hongro made by Toyo Ink) is RI on the sample film.
After printing with a tester (manufactured by Akira Seisakusho Co., Ltd.), a UV ink layer having a thickness of 4.5 μm is formed by curing with a medium pressure mercury lamp (80 W / cm, one lamp type; manufactured by Nippon Battery) UV curing device. Cellophane tape (18 mm
Width; made by Nichiban) is attached to a length of 15 cm, and 2K is placed on this
The peel adhesion is evaluated by applying a constant load with a manual load roll of g, fixing the film, and peeling one end of the cellophane tape in the 90 ° direction. Adhesiveness is evaluated according to the following 5 grades. 5: Ink layer does not peel at all 4: Ink layer less than 3% peels off 3: 3-10% ink layer peels off 2: 10-30% ink layer peels off 1: 30% or more ink Layers peel

3. Antistatic property The antistatic property is evaluated by the surface resistivity of the sample film. That is, using a Takeda Riken specific resistance measuring instrument, the surface specific resistance value (Ω / □) after 1 minute at an applied voltage of 500 V is measured and evaluated under the conditions of a measurement temperature of 23 ° C. and a measurement humidity of 50%. 1 × 10 ¹¹ Ω / □ or less is preferable.

4. Abrasion resistance Using a Gakken abrasion tester (manufactured by Tester Sangyo Co., Ltd.) set with dry gauze, apply 2 to the coating surface of the sample film.
Rubbing is performed 5 times back and forth while applying a load of 00 g, and the damage state of the coating film surface is visually determined. When the surface is almost unchanged before and after the treatment, it is indicated by ○, when the coating film is slightly damaged, it is indicated by Δ, and when the coating film is apparently removed, it is indicated by ×.

[Example 1] 2,6-naphthalenedicarboxylic acid component (30 mol%), isophthalic acid component (64 mol%), 5-Nasulfoisophthalic acid component (6 mol%),
An aqueous dispersion containing a ethylene glycol component (50 mol%) and a propylene oxide adduct component of bisphenol A represented by the following structural formula (50 mol%) and having a solid content of 10% using a copolyester having an intrinsic viscosity of 0.42. Was adjusted to obtain an aqueous liquid A.

[0055]

Embedded image [However, n + m = 4, ph = phenylene group]

On the other hand, a composition consisting of 90% by weight of polyethylene terephthalate (intrinsic viscosity 0.61) and 10% by weight of titanium oxide was melt extruded on a rotary cooling drum maintained at 20 ° C. to obtain an unstretched film, and then the unstretched film was The film was stretched 3.6 times in the machine axis direction, and then 65% by weight of the above aqueous coating liquid A, 25% by weight of an aqueous solution of sodium polystyrene sulfonate as an antistatic agent (concentration 10% by weight), and poly (oxy) as a surfactant. An amount of 8 g / m ² (wet) of a primer coating solution containing 10% by weight of an aqueous solution (concentration: 10% by weight) of ethylene / oxypropylene) nonyl ether (pour point −10 ° C., cloud point 59 ° C.) was applied by the kiss coating method. It was applied to both sides of the film. Subsequently, the film was stretched in the transverse direction by 3.6 times to obtain a coating film-coated biaxially stretched polyester film having a thickness of 188 μm.

Table 1 shows the adhesion of the magnetic paint, the adhesion of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

[Example 2] Methyl methacrylate component (4
5 wt%), a butyl acrylate component (45 wt%) and an N-methylolmethacrylamide component (10 wt%) were used to prepare an aqueous dispersion having a solid content concentration of 10% using an acrylic polymer (number average molecular weight: 27,000). Aqueous liquid B was obtained.

A coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 1 except that the aqueous liquid A used in Example 1 was changed to the aqueous liquid B.

Table 1 shows the adhesion of the magnetic paint, the adhesion of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

Example 3 The primer coating liquid used in Example 1 was prepared by using 35% by weight of an aqueous coating liquid A, 30% by weight of an aqueous coating liquid B, and an aqueous solution of sodium polystyrene sulfonate as an antistatic agent (concentration: 10% by weight). ) 25% by weight and 10% by weight of an aqueous solution (concentration 10% by weight) of poly (oxyethylene / oxypropylene) nonyl ether (pour point + 2 ° C, cloud point 84 ° C), which is a surfactant, are changed to a primer coating liquid. A coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 1 except for the above.

Table 1 shows the adhesiveness of the magnetic paint, the adhesive strength of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

[Example 4] The antistatic agent used in Example 3 was an acrylic polymer composed of a methyl methacrylate component (30 wt%), a butyl acrylate component (40 wt%) and a sodium methallyl sulfonate component (30 wt%). A coated film-covered biaxially stretched polyester film was obtained in exactly the same manner as in Example 3 except that the coalescence (number average molecular weight: 145,000) was changed.

Table 1 shows the adhesion of the magnetic paint, the adhesion of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

[Comparative Example 1] The primer coating solution used in Example 1 was prepared by using 65% by weight of the aqueous coating solution A, 25% by weight of an aqueous solution (concentration: 10% by weight) of sodium polystyrene sulfonate as an antistatic agent, and surface active agent. Polyoxyethylene nonyl phenyl ether which is an agent (pour point + 20 ° C, cloud point 4
A coating film-covered biaxially stretched polyester film was obtained in exactly the same manner as in Example 1 except that the primer coating solution was 10% by weight of an aqueous solution (6 ° C.) (concentration: 10% by weight).

Table 1 shows the adhesion of the magnetic paint, the adhesion of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

[Comparative Example 2] The primer coating liquid used in Example 1 was prepared by using 65% by weight of an aqueous coating liquid B, 25% by weight of an aqueous solution of sodium polystyrenesulfonate (concentration: 10% by weight) as an antistatic agent, and a surface active agent. Coating was performed in exactly the same manner as in Example 1 except that the primer coating liquid was changed to 10% by weight of an aqueous solution (concentration: 10% by weight) of polyoxyethylene nonyl ether (pour point: −28 ° C., cloud point: 26 ° C.) as an agent. A film-covered biaxially stretched polyester film was obtained.

Table 1 shows the adhesion of the magnetic coating, the adhesion of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

[Comparative Example 3] The primer coating liquid used in Example 1 was prepared by using 35% by weight of an aqueous coating liquid A, 30% by weight of an aqueous coating liquid B, and an aqueous solution of sodium polystyrene sulfonate as an antistatic agent (concentration: 10% by weight). ) 25 wt% and a polyoxyethylene nonylphenyl ether surfactant (pour point + 34 ° C, cloud point 100 ° C or higher) 8 wt% aqueous solution (concentration 10 wt%) A coated biaxially stretched polyester film was obtained in exactly the same manner as in Example 1.

Table 1 shows the adhesiveness of the magnetic paint, the adhesive strength of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

Comparative Example 4 A coated biaxially stretched polyester film was obtained in the same manner as in Example 1 except that the surfactant used in Example 1 was changed to an aqueous solution of sodium dodecylbenzenesulfonate.

Table 1 shows the adhesiveness of the magnetic paint, the adhesive strength of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

Comparative Example 5 The primer coating liquid used in Example 1 was prepared by using 55% by weight of aqueous coating liquid A, 25% by weight of an aqueous solution of sodium polystyrene sulfonate as an antistatic agent (concentration 10% by weight), and silicon oxide. 10% by weight of an aqueous dispersion (average particle size 200 nm) (concentration: 10% by weight) and a surfactant polyoxyethylene nonylphenyl ether (pour point + 34 ° C., cloud point 100 ° C. or higher)) (concentration: 10)
A coating film-covered biaxially stretched polyester film was obtained in exactly the same manner as in Example 1 except that the primer coating liquid was 10 wt%.

Table 1 shows the adhesiveness of the magnetic coating, the adhesive strength of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

[Comparative Example 6] The primer coating liquid used in Example 1 was prepared by using 30% by weight of an aqueous coating liquid A, 25% by weight of an aqueous coating liquid B, and an aqueous solution of sodium polystyrene sulfonate as an antistatic agent (concentration: 10% by weight). ) 25% by weight, cross-linked polystyrene resin (average particle size 240 nm) in water dispersion (concentration 10
10% by weight and polyoxyethylene nonyl ether which is a surfactant (pour point -28 ° C, cloud point 26 ° C)
A coating film-covered biaxially stretched polyester film was obtained in exactly the same manner as in Example 1 except that the primer coating liquid was changed to 10% by weight of the aqueous solution (concentration: 10% by weight).

Table 1 shows the adhesiveness of the magnetic paint, the adhesive strength of the UV ink, the antistatic property and the abrasion resistance of the treated surface of this film.
Are shown together.

[Comparative Example 7] Table 1 shows the adhesiveness of the magnetic paint, the adhesive strength of the UV ink, the antistatic property and the abrasion resistance of the biaxially oriented polyester film obtained without the primer coating in Example 1. Shown together.

[0078]

[Table 1]

[0079]

The easily-adhesive polyester film according to the present invention is superior in adhesive strength and antistatic property to conventional ones,
Moreover, it has particularly good abrasion resistance during handling and repeated use, and is therefore useful for, for example, magnetic cards, magnetic disks, printing materials, graphic materials, photosensitive materials and the like.

Claims (4)

[Claims] 1. At least one binder selected from the group consisting of (1) a copolymerized polyester resin and an acrylic copolymer on at least one side of an aromatic polyester film.
90% by weight, (2) substances having a sulfonate group in the molecule 3 ~
50% by weight, and (3) pour point of −50 to 10 ° C. and cloud point of 30
A coating having a composition of 0.5 to 30% by weight of a surfactant having a temperature of ℃ or more is used to form an easily adhesive coating having a dry coating thickness of 0.02 to 2 μm. Improved easy-adhesive polyester film. 2. The easily adhesive polyester film according to claim 1, wherein the aromatic polyester film is a white film containing a white pigment in an amount of 5 to 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 agent is an aqueous coating agent. 4. A laminated film in which a magnetic recording layer and / or a printing ink layer is provided on at least a part of the easily adhesive coating of the easily adhesive polyester film according to claim 2.