JP3528960B2 - Laminated polyester film - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a laminated polyester film having a coating layer. Specifically, it can be used with a wide range of materials such as a photographic photosensitive layer, a diazo photosensitive layer, a mat layer, a magnetic layer, an ink layer, an adhesive layer, a thermosetting resin layer, a UV curing resin layer, and a metal or inorganic oxide vapor deposition layer. The present invention relates to a laminated polyester film having a coating layer, which has excellent adhesiveness, excellent water resistance and thermal whitening preventive property, and can collect a waste film and reuse it as a film raw material.

[0002]

Laminated polyester films having adhesiveness are used in various fields such as magnetic tape base films, insulating tapes, photographic films, liquid crystal members, antireflection films, tracing films, and food packaging films. . Since the polyester film itself has insufficient adhesiveness, it is generally practiced to provide an anchor coat layer on the polyester film to improve the adhesiveness.

Many resins have been proposed as anchor coat resins. For example, for a film having relatively high polarity represented by polyester, use of a water-soluble or water-dispersible polyester resin or acrylic resin is disclosed in JP-A-54-43017 and JP-B-49-49. 10243, JP-A-52-19
No. 786, Japanese Patent Laid-Open No. 52-19787, Japanese Patent Laid-Open No. 58-124651. However, these conventional techniques were not sufficient in improving the adhesiveness.

Therefore, in order to improve the adhesiveness of the polyester film, it is possible to use various modified polyester resins, mainly graft-modified, as anchor coat resins, for example, Japanese Patent Laid-Open Nos. 2-3307 and 2-3.
-171243, Japanese Patent Laid-Open No. 2-310048, Japanese Patent Laid-Open No. 3-273015, and Japanese Patent Publication No. 3-676.
No. 26, etc. However, when this graft-modified polyester resin is used as a resin for anchor coat, the adhesive property is improved, but the adhesive property under wet condition is poor.

Therefore, it is possible to improve the adhesiveness under wet condition by using a crosslinking agent together.
633, Japanese Patent Publication No. 6-24765, Japanese Patent Publication 6
No. 39154, Japanese Patent Publication No. 6-39548, etc.

However, although the adhesiveness under wet condition is improved by using a cross-linking agent together, a waste film which has not been made into a product at the time of polyester film production is melt-molded into pellets and reused as a film raw material. Moreover, the obtained film was of poor quality and could not be reused practically. Therefore, even if it is a coated polyester film having excellent water resistance and adhesiveness, the waste film that has not become a product at the time of film production is either discarded or is used with a limited amount of application or mixture. Is. Therefore, it is a problem from the viewpoint of high manufacturing cost and environmental load caused by disposal.

Further, in optical applications and the like, there is a problem that the film is whitened to reduce transparency and fine surface protrusions are formed in a high temperature environment during or after film processing. The whitening of the film and the formation of minute surface protrusions occur when crystals of the polyester oligomer in the film are deposited on the surface.

As a method of suppressing the oligomer deposition on the film surface, a method of using a polyester having a low oligomer content produced by solid phase polymerization (Japanese Patent Laid-Open No. 55-
89330, JP-A-55-189331), a method of coating the film surface with polyester having a low oligomer content (JP-A-11-300918), and the like.

However, these methods alone cannot improve the adhesion, water resistance, and recoverability, and even when combined with the known coating film technology, the adhesion, water resistance, recovery, and A polyester film excellent in all of the heat whitening preventive properties has not been obtained.

[0010]

That is, the object of the present invention is to solve the above-mentioned conventional problems and provide a laminated polyester film excellent in all of adhesiveness, water resistance, recoverability, and thermal whitening preventive property. Especially.

[0011]

The present invention has been made in view of the above situation, and the laminated polyester film capable of solving the above problems is as follows.

That is, the first invention of the present invention is that a water-soluble or water-dispersible resin and a water-based solvent are main constituent components on at least one side of a polyester film , and a nitrogen source is used.
Water-based coating that does not contain cross-linking agents containing silicone or phenols
A laminated film provided with a coating layer formed using a cloth liquid , wherein the water-soluble or water-dispersible resin is
A resin comprising any one of (a) to (c),
An ink layer is provided on the coating layer surface of the layer film, and pressure boil treatment is performed.
JIS-K5400 after processing for 1 hour at 120 ° C
The peeling test was performed, and the area ratio (water resistance) of the ink remaining without peeling was 90% or more, and the laminated film was 280
B value of recovered pellets obtained by melt extrusion at ℃ and before melting
The difference in the b value of the laminated film of (the discoloration value after melt molding) is 1
0 or less, and the laminated film is heated at 150 ° C. for 30 minutes
The haze value after heating and the haze value of the laminated film before heating.
The laminated polyester film has a difference from the Ize value (change in haze value after heating) of 20% or less. (A) at least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Aromatic polyester resin graft copolymer (b) containing an acrylic resin having an acid value of 200 eq / t or more, or
Is a copolymer thereof (excluding (c) ) (c) at least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Acrylic resin containing an acid value of 200 eq / t or more
Copolymer of

A second invention is that the coating liquid further comprises nitrogen.
A laminated polyester film according to the first invention, wherein the this <br/> to use a crosslinking agent that does not contain atoms or phenols. The third invention is that the coating liquid further comprises an acid.
A laminated polyester film according to the first invention, characterized in that a compound is used .

In a fourth aspect of the present invention, the coating amount of the coating layer after drying is 0.01 to 1.0 g / m ² , and the laminate according to the first, second or third aspect of the invention. It is a polyester film.

A fifth invention is the laminated polyester film according to the first invention, characterized in that the film is used for printing. A sixth invention is the laminated polyester film according to the first invention, wherein the film is used as a base material film of an optical member.

A seventh aspect of the present invention is an unstretched or uniaxially stretched film.
On at least one side of the polyester film of
Or water-dispersible resin, and water-based solvent as the main constituent
And contains a crosslinking agent containing nitrogen atoms or phenols.
After applying the water-based coating solution, dry it
By stretching at least uniaxially and heat fixing,
Laminated polyester fiber having a coating layer obtained by crosslinking the above resin
A method for producing a film, wherein the laminated polyester
The film has an ink layer on the surface of the coating layer,
JIS-K540 after 1 hour at 120 ℃
After performing the peeling test described in 0, the surface of the ink that remained without peeling
The product (water resistance) is 90% or more, and the laminated film is 2
The b value and the melting point of the recovered pellets obtained by melt extrusion molding at 80 ° C
Difference in b value of laminated film before melting (discoloration value after melt molding)
Of 10 or less, and the laminated film at 150 ° C. for 30 minutes
Haze value after heating for a while and the laminated film before heating
20% difference from the haze value (change in haze value after heating)
In the following, the water-soluble or water-dispersible resin is (d) to
A resin comprising any one of (f), which is contained in the coating liquid.
An acid compound is added, or the width direction of the film after stretching is fixed.
The heating of the coating layer with an infrared heater
Characterized by using at least one cross-linking promoting means
It is a method for producing a laminated polyester film. (D) At least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Aromatic polyester resin graft copolymer (e) containing an acrylic resin having an acid value of 200 eq / t or more, or
Is a copolymer thereof (excluding (f) ) (f) at least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Acrylic resin containing an acid value of 200 eq / t or more
Copolymer of

An eighth aspect of the invention is that the coating liquid further contains nitrogen.
Use cross-linking agents that do not contain atoms or phenols.
And a laminated polyester fiber according to the seventh invention,
This is the method of manufacturing the film.

[0018]

The function of the laminated polyester film of the present invention is
It is necessary that the water resistance value of the coating layer surface is 90% or more, and preferably 95% or more. 90% water resistance
If it is less than the above range, the adhesiveness under wet condition becomes poor when the ink layer is formed on the surface of the coating layer of the laminated polyester film. The water resistance value defined in the present invention means that the UV seal ink is applied to the surface of the coating layer of the laminated film, and after UV curing, pressure boil treatment is performed at 120 ° C. for 1 hour, and then JIS-K is used.
The peeling test described in 5400 was performed, and the area ratio (%) of the ink remaining without peeling is meant.

The laminated polyester film of the present invention must have a discoloration value of 10 or less after melt molding.
When the discoloration value exceeds 10, the quality of the film deteriorates remarkably when the recovered pellet is used as a film raw material.

The color change value after melt molding defined in the present invention is a parameter represented by the difference in color b value between the pellets obtained by melt molding a laminated polyester film and the laminated polyester film before melt molding.

Specifically, the laminated polyester film is cut into strips, dried under reduced pressure, and then cut with a model testing machine to
It is melt extruded at a temperature of 80 ° C., cooled in water and then cut into pellets. This pellet is abbreviated as a recovery pellet. The color b value between the recovered pellet and the laminated polyester film before the test is measured, and the difference between the two is defined as the discoloration value after the melt molding. The color b value means ab value in Lab space measured by a photoelectric colorimeter.

The background using this parameter will be described. When manufacturing a polyester film, both ends gripped by clips during lateral stretching with a tenter, both ends that do not meet the predetermined product width when slitting, roll-shaped film that has been degraded in terms of quality, at the start and end of film formation A waste film that does not become a product is always generated due to time, changing conditions, trouble, etc. Generally, the scrap film is crushed into flakes, melted in an extruder, discharged into water in a strand form from a die, then cut into pellets, re-formed as recovered pellets and re-formed as a film raw material. Used.

However, the film using the recovered pellets made of the laminated polyester film having the coating layer has a low quality due to the presence of foreign matters causing fish eyes or due to coloring etc. due to the heat history during the production of the recovered pellets. Become. Therefore, transparency, coarse projections caused by foreign matter, applications where defects such as fish eyes are a problem,
Especially for optical applications, it is not possible to reuse a waste film that does not become a product as a film raw material.

This phenomenon was analyzed in detail, and a laminated polyester film having a coating layer was remelted by a model test and remolded into pellets, and the discoloration value of the film when the pellets were biaxially stretched (melt molding It was found that the quality of the film when the laminated polyester film was actually produced by using the film raw material containing the recovered pellets could be grasped by using the later color change value) as a parameter. As a result, in order to reduce the deterioration of the quality of the film using the recovered pellets, that is, in order to be a recoverable laminated polyester film, it is necessary to set the discoloration value after the melt molding to 10 or less. .

Further, the laminated polyester film of the present invention is required to have a change in haze value of 20% or less after heating. It is preferably 15% or less, and particularly preferably 10% or less. Change in haze value after heating is 2
If it exceeds 0%, the whitening of the film becomes remarkable, and the effect on the appearance and performance cannot be neglected particularly when the film is used for heat treatment in a post-processing step, for example, for printing or optical applications.

The change in haze value after heating means the difference between the haze value after heating at 150 ° C. for 30 minutes and the haze value of the laminated polyester film before heating. This parameter is used for predicting thermal whitening of the film when the laminated polyester film of the present invention is heat-treated in a post-processing step and for quality control at the film stage.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the laminated polyester film of the present invention will be described in detail below.

(Polyester Resin for Base Film) The polyester film used as the base film of the present invention contains polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate or a constituent component of these resins as a main component. Although a copolymer is used, a biaxially stretched film formed of polyethylene terephthalate is particularly preferable. The method for producing these polymers is not particularly limited, and polyesters in which the oligomer content is reduced by solid-phase polymerization or solvent extraction of the polymers may be used.

The polyester film used in the present invention contains a polycondensation catalyst (in the case of the transesterification method,
A transesterification catalyst is also used), and a heat stabilizer such as phosphoric acid or a phosphoric acid compound is used as an essential component. In addition to these, it is also possible to include an appropriate amount of an alkali metal salt or an alkaline earth metal salt so that the sheet-shaped molten polyester resin is adhered and solidified on the rotating cooling roll by the electrostatic application method, and unstretched to have a uniform thickness. It is preferable because a sheet can be obtained.

In order to improve handling properties such as slipperiness, winding property and blocking resistance of the film, and abrasion properties such as abrasion resistance and scratch resistance, inert particles are added to the polyester film as the base material. It is preferable to contain it. Other additives may be contained in the polyester resin as required. As an additive,
For example, an antioxidant, a light resistance agent, an anti-gelling agent, an organic lubricant, an antistatic agent, an ultraviolet absorber, a surfactant and the like can be mentioned.

When the laminated polyester film of the present invention is used as a base film for an optical member, it is required to have excellent handling properties while maintaining a high degree of transparency. It is preferable that substantially no particles are contained and only the coating layer contains fine particles.

(Coating Liquid) The water-soluble or water-dispersible resin used in the coating layer of the base film in the present invention comprises any of the following (a) to (c).
It is a resin. (A) at least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Aromatic polyester resin graft copolymer (b) containing an acrylic resin having an acid value of 200 eq / t or more, or
Is a copolymer thereof (excluding (c) ) (c) at least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Acrylic resin containing an acid value of 200 eq / t or more
Copolymer of

The aromatic polyester resin means that the aromatic dicarboxylic acid component is 30 mol% in the acid component of the polyester.
It means the resin contained above. 3 aromatic dicarboxylic acid components
When it is less than 0 mol%, the hydrolysis resistance of the polyester resin becomes remarkable and the water resistance deteriorates.

As the polar group which does not deteriorate the water resistance of the coating layer, an amine salt of a carboxylic acid which is decomposed after heating to reduce the polarity is exemplified. The amines that can be used are
It is necessary to vaporize the coating under the drying conditions, and examples thereof include ammonium, diethylamine, triethylamine and the like.

In addition , one or more resins or two or more copolymers selected from an aqueous aromatic polyester resin or an aqueous acrylic resin having an acid value of 200 eq / t or more,
It is-containing radical polymer comprising at least one monomer containing an acid anhydride at 5 wt% or more having a double bond
It If it is less than 5% by weight, the effect of water resistance cannot be sufficiently obtained.

By introducing the above-mentioned acid anhydride into the resin, it becomes possible to carry out a crosslinking reaction between resin molecules. That is, the acid anhydride in the resin is converted into a carboxylic acid in the coating solution by hydrolysis or the like, and reacts with the acid anhydride or the active hydrogen group of another molecule between molecules due to the thermal history during drying and film formation. To produce an ester group and the like to crosslink the resin in the coating layer, thereby exhibiting water resistance and thermal whitening preventive property.

As the monomer containing an acid anhydride having a double bond, maleic anhydride, itaconic anhydride, 2,
Examples thereof include 5-norbornene dicarboxylic acid and tetrahydrophthalic anhydride. Further, the radical polymer may be a copolymer with other polymerizable unsaturated monomer.

Other polymerizable unsaturated monomers include fumaric acid, monoethyl fumarate, diethyl fumarate, diester fumarate and other fumaric acid monoesters or diesters; maleic acid, monoethyl maleate, diethyl maleate, Maleic acid monoesters or diesters such as dibutyl maleate; itaconic acid, monoesters or diesters of itaconic acid; maleimides such as phenylmaleimide; styrene derivatives such as styrene, α-methylstyrene, t-butylstyrene, chloromethylstyrene. Vinyltoluene, divinylbenzene, etc .; alkyl acrylate, alkyl methacrylate (as the alkyl group, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, 2-ethylhexyl group) Group, a cyclohexyl group, a phenyl group, a benzyl group, acrylic polymerizable monomers such as phenylethyl group, etc.); 2-hydroxyethyl acrylate,
2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, hydroxy-containing acrylic monomer of 2-hydroxypropyl methacrylate; acrylamide, methacrylamide, N-methylmethacrylamide, N-methylacrylamide, N-methylolacrylamide, N-methylolmethacryl Amide, N, N-
Dimethylol acrylamide, N-methoxymethyl acrylamide, N-methoxymethyl methacrylamide, N
-Acrylic monomer containing amide group of phenylacrylamide; N, N-diethylaminoethyl acrylate, N,
Amino group-containing acrylic monomer of N-diethylaminoethyl methacrylate; Glycidyl acrylate, epoxy group-containing acrylic monomer of glycidyl methacrylate; Acrylic acid, methacrylic acid and their salts (sodium salt, potassium salt, ammonium salt), etc. carboxyl Acrylic monomers containing groups or salts thereof, and the like.

The coating liquid used for forming the coating layer of the present invention is mainly composed of a water-soluble or water-dispersible resin and an aqueous solvent. As described above, as the water-soluble or water-dispersible resin, one or more resins selected from an aqueous aromatic polyester resin or an aqueous acrylic resin having an acid value of 200 eq / t or more, or two or more resins It is preferable that the polymer contains 5% by weight or more of a radical polymer composed of at least one monomer containing an acid anhydride having a double bond.

In this case, it is particularly preferable to add an acid compound when preparing the coating solution. By adding this acid compound,
Since it is possible to improve the crosslinking of the resin by promoting the acid anhydride and esterification reaction of the carboxylic acid group in the resin,
The laminated polyester film of the present invention is suitable for having a water resistance value of 90% or more, which is an important constituent factor.

The addition amount of the acid compound is 1 to 1 with respect to the resin.
A range of 0% by weight is preferred. Further, although it is possible to use various compounds as the acid compound, carboxylic acid having a low boiling point is easily vaporized by heat during film formation, has a small residual amount in the coating layer and has a small adverse effect at the time of remaining, and has a low boiling point. preferable. As the low boiling point carboxylic acid, formic acid, acetic acid, propionic acid,
Butyric acid, valeric acid, heptanoic acid, etc. can be mentioned.

In the present invention, in order to satisfy the water resistance value and the discoloration value, it is necessary to use a crosslinking agent containing no nitrogen atom or phenol in the crosslinking reaction using the acid anhydride. preferable.

The cross-linking agent containing a nitrogen atom or phenol is oxidized and decomposed by heat or the like to form a compound having a conjugated structure centered on the nitrogen atom and the aromatic ring. As a result, coloring becomes remarkable. However, in the present invention, the use of these cross-linking agents is not completely denied, and if the water resistance value and discoloration value of the present invention are satisfied, an appropriate amount is used according to the type of the cross-linking agent (curing resin). It is possible to

Examples of the cross-linking agent containing a nitrogen atom include:
(1) Adducts of urea, melamine, benzoguanamine and the like with formaldehyde, (2) amino resins such as alkyl ether compounds consisting of these adducts and alcohols having 1 to 6 carbon atoms, (3) containing nitrogen atoms Examples thereof include polyfunctional epoxy compounds, (4) polyfunctional isocyanate compounds, (5) blocked isocyanate compounds, (6) polyfunctional aziridine compounds, and (7) oxazoline compounds.

Examples of the amino resin described in (2) above include methoxylated methylol urea, methoxylated methylol N, N-ethylene urea, methoxylated methylol dicyandiamide, methoxylated methylol melamine, methoxylated methylol benzoguanamine, butoxylated methylol melamine. , Butoxylated methylol benzoguanamine and the like. Among these, methoxylated methylol melamine, butoxylated methylol melamine, and methylolated benzoguanamine are preferable.

Examples of the polyfunctional epoxy compound containing a nitrogen atom described in (3) above include, for example, triglycidyl iso compound.
Cyanurate, diglycidyl propylene urea , etc. are mentioned.

Examples of the polyfunctional isocyanate compound described in (4) above include low-molecular or high-molecular aromatic or aliphatic diisocyanates and trivalent or higher polyisocyanates.

Examples of polyisocyanates include tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, and trimers of these isocyanate compounds. Is exemplified.

Further, an excess amount of these isocyanate compounds and a low molecular weight active hydrogen compound such as ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, or polyester polyol. Examples thereof include a terminal isocyanate group-containing compound obtained by reacting with a polymer active hydrogen compound such as compounds, polyether polyols and polyamides.

The blocked isocyanate described in (5) above can be synthesized by addition reaction of the above isocyanate compound and a blocking agent by a known method. Examples of the isocyanate blocking agent include (a) phenol, cresol, xylenol, resorcinol,
Phenols such as nitrophenol and chlorophenol, (b) thiophenols such as thiophenol and methylthiophenol, (c) oximes such as acetoxime, methyl etiketoxime and cyclohexanone oxime, (d) methanol, ethanol, propanol,
Alcohols such as butanol, (e) ethylene chlorohydrin, halogen-substituted alcohols such as 1,3-dichloro-2-propanol, (f) t-butanol, t
-Tertiary alcohols such as pentanol, (g) ε-
Lactams such as caprolactam, δ-valerolactam, ν-butyrolactam, β-propyllactam, (h)
Aromatic amines, (i) imides, (j) acetylacetone, acetoacetic acid ester, active methylene compounds such as malonic acid ethyl ester, (k) mercaptans,
Examples include (l) imines, (m), ureas, (n) diaryl compounds, (o) sodium bisulfite, and the like.

Examples of the crosslinking agent containing phenols include, for example, phenol formaldehyde resins of condensation products with formaldehyde such as alkylated phenols and cresols, and polyfunctional epoxy compounds containing bisphenol A.
Thing .

Examples of the phenol-formaldehyde resin include alkylated (methyl, ethyl, propyl,
Isopropyl or butyl) phenol, p-tert
-Amylphenol, 4,4'-sec-butylidenephenol, p-tert-butylphenol, o-cresol, m-cresol, p-cresol, p-cyclohexylphenol, 4,4'-isopropylidenephenol, p-nonylphenol , P-octylphenol, 3-pentadecylphenol, phenol, phenyl o-cresol, p-phenylphenol, xylenol and the like, and condensates of formaldehyde. Polyfunctional epoxy containing bisphenol A
Examples of the si compound include bisphenol A diglycone
Sidyl ether and its oligomers, hydrogenated bisphenes
Diglycidyl ether of Nool A and its oligomer
And so on.

In the present invention, the coating liquid used for forming the coating layer is preferably an aqueous coating liquid. When the above-mentioned aqueous coating solution is applied to the surface of the substrate film, in order to improve the wettability to the substrate film and coat the coating solution uniformly, a known anionic surfactant or nonionic surfactant is used. Is preferably added in an appropriate amount.

In the aqueous coating solution, inorganic and / or heat resistant polymer particles are added in order to impart other functions such as handling property, antistatic property and antibacterial property to the film.
Additives such as antistatic agents, ultraviolet absorbers, organic lubricants, antibacterial agents, and photooxidation catalysts can be included.

In particular, when the polyester film as the base material contains substantially no inactive particles, in order to improve the handling property of the film, inorganic and / or heat-resistant polymer particles are added to the aqueous coating solution. It is necessary to contain it to form irregularities on the surface of the coating layer. Furthermore, since the coating liquid is water-based, a plurality of water-soluble resins, water-dispersible resins, emulsions and the like may be added to the coating liquid in order to improve performance.

As the solvent used for the coating solution, alcohols such as ethanol, isopropyl alcohol and benzyl alcohol may be mixed in addition to water in an amount of less than 50% by weight with respect to the total coating solution. Furthermore, if the amount is less than 10% by weight, organic solvents other than alcohols may be mixed in a soluble range. However, the total amount of alcohols and other organic solvents in the coating liquid is preferably less than 50% by weight.

When the amount of the organic solvent added is less than 50% by weight, the drying properties at the time of coating and drying are improved, and the appearance of the coating layer is improved as compared with the case where only water is used.
When the amount is 50% by weight or more, the evaporation rate of the solvent is increased, so that the concentration of the coating liquid changes during coating, the viscosity of the coating liquid increases, and the coating property deteriorates. As a result, a defective appearance of the coating layer is likely to occur. In addition, environmental aspects, worker health aspects,
It is not preferable because of the risk of fire.

(Production of Laminated Polyester Film) A method for producing a laminated polyester film of the present invention will be described by taking a polyethylene terephthalate (hereinafter abbreviated as PET) film as an example, but the present invention is not limited to this.

After sufficiently drying the PET resin in a vacuum, the PET resin was supplied to an extruder, and the molten PET resin at about 280 ° C. was melt-extruded in a sheet form on a rotating cooling roll from a T-die and cooled and solidified by an electrostatic application method. An unstretched PET sheet is obtained.
The unstretched PET sheet may have a single-layer structure or a multi-layer structure formed by a coextrusion method. Further, in applications requiring a high degree of transparency, such as optical applications, it is preferable that the PET resin does not substantially contain inert particles.

The obtained unstretched PET sheet was mixed with 80-1
A uniaxially stretched PET film is obtained by stretching the roll in a longitudinal direction 2.5 to 5.0 times with a roll heated to 20 ° C. further,
Hold the edge of the film with a clip, 70-140 ℃
To the hot air zone heated to 2.5 to 5.
Stretch to 0 times. Subsequently, it is introduced into a heat treatment zone of 160 to 240 ° C. and heat treatment is performed for 1 to 60 seconds to complete the crystal orientation.

At any stage of this film manufacturing process, P
At least one surface of the ET film is coated with the water-based coating liquid containing the water-soluble or water-dispersible resin and the water-based solvent as main components. The coating layer may be formed only on one side of the PET film, but in order to prevent the oligomer from precipitating on the film surface and suppress the increase in the haze value after heating the film, the coating layer may be formed on both sides of the PET film. It is more effective to form.

The solid content concentration of the resin composition in the aqueous coating liquid is preferably 5 to 35% by weight, particularly preferably 7 to 15% by weight.

As a method for coating the PET film with this aqueous coating solution, any known method can be used. For example, reverse roll coating method, gravure coating method, kiss coating method, die coater method, roll brushing method, spray coating method, air knife coating method, wire bar coating method, pipe doctor method, impregnation coating method, curtain coating method, etc. To be These methods can be performed alone or in combination.

The coating layer may be provided by applying the coating solution to a biaxially stretched PET film and drying it (off-line coating method), or after applying the coating solution to an unstretched or uniaxially stretched PET film. It may be dried, stretched in at least uniaxial direction, and heat-fixed (in-line coating method).

From the viewpoint of the effect of the present invention, the latter in-line coating method is preferable. The film coated with the coating solution is introduced into a tenter and heated for transverse stretching and heat setting. At that time, a stable coating layer can be formed by a thermal crosslinking reaction.

In the case of a so-called in-line coating method in which the coating liquid is applied to an unstretched or uniaxially stretched PET film and then dried and stretched, only the solvent component such as water is removed and coated in the drying step after coating. It is necessary to select a temperature and time at which the crosslinking reaction of the layer does not proceed.

The drying temperature is preferably 70 to 140 ° C., and the drying time is adjusted according to the coating liquid and the coating amount, but the product of temperature (° C.) and time (seconds) should be 3,000 or less. Is preferred. If the product exceeds 3,000, the coating layer starts a crosslinking reaction before stretching, and the coating layer is cracked, which makes it difficult to achieve the object of the present invention.

The stretched film is usually subjected to a relaxation treatment of about 2 to 10%, but in the present invention, the infrared heater is used in a state where the strain of the coating layer is small, that is, the length in the width direction of the film is fixed. It is preferable to heat the coating layer according to. The coating layer is heated at 250 to 260 ° C.
It is particularly preferable to perform it in a short time of 0.5 to 1 second.

By using such a method, crosslinking of the resin in the coating layer is further promoted, the resin becomes stronger, and the water resistance and the heat whitening preventive property which are the effects of the present invention are further improved.

If the temperature or time during heating by the infrared heater exceeds the upper limit of the above-mentioned preferable range, crystallization or dissolution of the film is likely to occur, which is not preferable. On the other hand, when the temperature or time during heating is less than the lower limit of the above-mentioned preferable range, the cross-linking of the coating layer is insufficient, and the water resistance and the heat whitening preventive property are likely to be insufficient.

In the present invention, the coating amount of the coating layer in the finally obtained laminated polyester film is 0.0
It is preferably from ¹ to 1.0 g / m ² . When the coating amount of the coating layer is less than 0.01 g / m ² , the effect on the adhesiveness is almost lost. On the other hand, the applied amount is 1.0 g / m
^If it exceeds ² , the recoverability will be adversely affected.

The coating layer of the laminated polyester film of the present invention has good adhesiveness to various materials, but in order to further improve the adhesiveness and printability, the coating layer may be subjected to corona treatment or flame treatment, if necessary. A surface treatment such as electron beam irradiation may be performed.

The coating layer of the laminated polyester film obtained in the present invention has good adhesive strength in a wide range of applications. Specifically, it is a photographic photosensitive layer, a diazo photosensitive layer, a matte layer, a magnetic layer, an inkjet ink receiving layer, a hard coat layer, an ultraviolet curable resin, a thermosetting resin, a printing ink or UV.
Ink, adhesive such as dry laminate and extrusion laminate, thin film layer obtained by vacuum deposition of metal or inorganic material or oxide thereof, electron beam deposition, sputtering, ion plating, CVD, plasma polymerization, etc.,
An organic barrier layer etc. are mentioned.

[0074]

EXAMPLES Next, the present invention will be described in detail with reference to examples and comparative examples, but the present invention is not of course limited to the following examples. The evaluation method used in the present invention is as follows.

(1) A hard coat agent (SEICA BEAM EXF01 (B) manufactured by Dainichiseika Co., Ltd.) was applied to the coating layer surface of the adhesive film with a # 8 wire bar, and dried at 70 ° C. for 1 minute to remove the solvent.
Then, while the film is running at a feeding speed of 5 m / min, irradiation energy is 200 mJ / c using a high pressure mercury lamp.
Under the conditions of m ² and irradiation distance of 15 cm, a hard coat layer having a thickness of 3 μm was formed.

Adhesiveness of the obtained film is determined by a test method according to JIS-K5400, 8.5.1. Specifically, using a cutter guide with a gap of 2 mm,
100 square cuts are made through the hard coat layer and the coating layer to reach the base film. Next, cellophane adhesive tape (Nichiban, No. 405; 24 mm
(Width) on the cut surface of the grid and rub it with an eraser to ensure complete attachment. After that, the cellophane adhesive tape is vertically peeled off from the film, the number of squares peeled off from the film is visually counted, and the adhesiveness is calculated from the following formula. It should be noted that those that are partially peeled off in the squares are counted as peeled squares. Adhesiveness (%) = (1-number of peeled squares / 100) × 100

(2) Water resistance The polyester film prepared by the method described in (1) above and having a hard coat layer with a thickness of 3 μm formed on the surface of the coating layer was immersed in warm water at 60 ° C. for 168 hours. Next, the film was taken out from warm water, water adhering to the film surface was removed, and the film was left at room temperature for 12 hours.

After that, the adhesiveness is obtained by the same method as in the above (1), and ranked according to the following criteria. A: 100% O: 99 to 96% B: 95 to 80% X: 79 to 0%

(3) Offset ink (Best Cure 161 manufactured by T & K Toka Co., Ltd.) was transferred to the coating layer surface of the water resistant film by an RI tester (RI-3 manufactured by Meisei Seisakusho). Then, while the film was running at a feeding speed of 5 m / min, irradiation energy was 200 mJ / cm ² using a high pressure mercury lamp,
An ink layer having a thickness of 1 μm was formed under an irradiation distance of 15 cm.

The obtained film was put into an autoclave containing water (SR-240 manufactured by Tommy Seiko Co., Ltd.), and 120
Pressurized boiled at 1 ° C for 1 hour. After the boil treatment, the autoclave was returned to normal pressure, and the film was taken out from the autoclave. Remove the water adhering to the film surface,
It was left at room temperature for 12 hours.

A peeling test is performed on the ink layer side surface of the boiled film in the same manner as in (1) above.
Obtain the water resistance value from the following formula. It should be noted that those that are partially peeled off in the squares are counted as peeled squares. Water resistance value (%) = (1-number of peeled squares / 100) × 100

(4) La by a hue color difference meter (Z-1001DP manufactured by Nippon Denshoku Co., Ltd.)
The b value is measured and the b value is used.

(5) The laminated polyester film having the discoloration value coating layer after melt molding was cut into strips and dried under reduced pressure of 133 Pa at 135 ° C. for 6 hours, and then an extruder (made by Ikegu Tekko KK, PCM). -30),
The molten resin was extruded in a strand shape from a nozzle having a diameter of 5 mm at a discharge rate of 200 g / min, a cylinder temperature of 280 ° C., and a rotation speed of 80 rpm, cooled in a water tank, and then cut to obtain recovered pellets. The elapsed time from the start of supplying the strip-shaped film to PCM-30 to the start of flowing out the molten resin from the nozzle was 130 seconds.

The b value (b) of the recovered pellets and the b value (b ₀ ) of the laminated film before the test were measured by a color difference meter, and these differences are defined as the discoloration value after the melt molding. Discoloration value = b−b ₀

(6) Foreign matter in film As a raw material polymer for film, the intrinsic viscosity is 0.62 dl.
/ G, and the PET pellets containing substantially no particles and the recovered pellets prepared in (5) above are 60: 4.
The mixture was mixed at a weight ratio of 0 and dried at 135 ° C. for 6 hours under a reduced pressure of 133 Pa.

Then, the mixed resin pellets were supplied to an extruder (PCM-30, manufactured by Ikegai Tekko KK), and the cylinder temperature was 280 ° C., the discharge rate was 250 g / min, and the rotation speed was 150 r.
The sheet was melt extruded from a T-die at pm and rapidly cooled and solidified on a metal roll kept at a surface temperature of 20 ° C. by an electrostatic application method to obtain an unstretched sheet having a thickness of 1400 μm. PC
The elapsed time from the start of the supply of the strip film to M-30 to the start of the outflow of the molten resin from the T die was 310 seconds.

Next, this unstretched sheet was heated to 100 ° C. with a heated roll group and an infrared heater, and then stretched 3.5 times in the longitudinal direction with roll groups having different peripheral speeds to obtain a uniaxially oriented PET film. Obtained. Subsequently, the end portion of the film is grasped with a clip, introduced into a hot air zone heated to 130 ° C. and dried, and then stretched 4.0 times in the width direction to obtain a thickness of 1
A biaxially stretched PET film of 00 μm was obtained.

The obtained film is 250 mm × 250 m
The number of foreign matter having a diameter of 20 μm or more when observed from a direction perpendicular to the film surface with a microscope with a scale is 250 mm × 250 mm (0.0
Measure over the entire range of 625 m ² ). This is performed to the film strip 10 sheets, the total number of the resulting foreign substance divided by the total observation area (0.625 M ^2), in terms of the number of foreign substances per unit area 1 m ² (number / m ^2), The first decimal place was rounded off. The number of foreign matters per 1 m ^{2 of} unit area is ranked according to the following criteria. ⊚: 0 pieces / m ² ○: 1 to 3 pieces / m ² Δ: 4 to 6 pieces / m ² ×: 7 pieces or more / m ²

(7) Film Appearance The obtained film is observed by transmitted light and reflected light, the state of the film is visually observed, and the rank is classified according to the following criteria. The observation was conducted by 5 persons who were familiar with the evaluation,
The highest rank is used as the evaluation rank. If two ranks have the same number, the center of the three ranks is adopted. For example, if ◎ and ○ are each 2 people and △ is 1 person, ○, if ◎ is 1 person and ○ and △ are 2 people respectively, ○,
If ◎ and △ are each 2 people and ○ is 1 person, ○ is adopted respectively. ⊚: Transparent and uniform with no coloration ○: Slightly colored but transparent and uniform Δ: Colored and slightly turbid observed ×: Remarkably colored, turbid or opaque Some parts are observed

(8) Change in haze value after heating Two pieces of film were cut into 8 cm × 10 cm strips,
A haze meter (TC-H3DP manufactured by Tokyo Denshoku Co., Ltd.) is used to measure each 8 points twice. The average value of the measured values of 16 points in total is defined as the initial haze value H ₀ (%). Hold these strip-shaped films with clips and hold them in a hot air oven at 150 ° C for 30
Heated for minutes. After allowing the film to cool, the haze value H after heating was measured in the same manner as in the measurement method of the initial haze value H _0.
Measure ₁ (%). The difference between these haze values (H ₁ −
H ₀ ) is defined as the change in haze value after heating.

(Preparation of Copolyester Resin) 163 parts by weight of dimethyl terephthalate and 163 parts of dimethyl isophthalate were placed in a stainless steel autoclave equipped with a stirrer, a thermometer, and a partial reflux condenser.
Parts by weight, 169 parts by weight of 1,4 butanediol, 324 parts by weight of ethylene glycol, and 0.5 parts by weight of tetra-n-butyl titanate are charged, and the temperature is 160 ° C to 220 ° C.
Up to 4 hours, the transesterification reaction was performed.

Then, 14 parts by weight of fumaric acid and 203 parts by weight of sebacic acid were added, and the temperature was raised from 200 ° C. to 220 ° C.
The temperature was raised over time to carry out an esterification reaction. Then
After raising the temperature to 255 ° C. and gradually reducing the pressure of the reaction system, 29
The reaction was performed under a reduced pressure of Pa for 1 hour and 30 minutes to obtain a copolyester resin (A-1). The obtained copolyester resin was light yellow and transparent.

Copolyester resins (A-2, 3) having different compositions were obtained by the same method. (A-1), (A-
Table 1 shows the composition and weight average molecular weight measured by NMR for 2) and (A-3).

[0094]

[Table 1]

Example 1 (1) Production of Graft Resin In a reactor equipped with a stirrer, a thermometer, a reflux device and a constant amount dropping device, 75 parts by weight of a copolyester resin (A-1),
56 parts by weight of methyl ethyl ketone and 19 parts by weight of isopropyl alcohol were added, and the mixture was heated and stirred at 65 ° C. to dissolve the resin. After the resin was completely dissolved, 15 parts by weight of maleic anhydride was added to the polyester solution.

Then, a solution prepared by dissolving 10 parts by weight of styrene and 1.5 parts by weight of azobisdimethylvaleronitrile in 12 parts by weight of methyl ethyl ketone was added dropwise to the polyester solution at 0.1 ml / min, and the mixture was further stirred for 2 hours. Continued. After sampling for analysis from the reaction solution,
5 parts by weight of methanol were added. Then, 300 parts by weight of water and 15 parts by weight of triethylamine were added to the reaction solution, and 1
Stir for hours.

Then, the internal temperature of the reactor was raised to 100 ° C.,
Methyl ethyl ketone, isopropyl alcohol, and excess triethylamine were distilled off to obtain a water-dispersed graft polymerization resin B-1. The water-dispersed graft resin (B-
1) was light yellow and transparent. The acid value of this graft is 1
It was 400 eq / t.

(2) Preparation of coating liquid 40 parts by weight of an aqueous dispersion of 25% by weight of the obtained aqueous dispersion graft resin (B-1), 24 parts by weight of water and 36 parts by weight of isopropyl alcohol were mixed, respectively. Propionic acid and anionic surfactant are each 1% by weight with respect to the coating liquid, and colloidal silica fine particles (manufactured by Nissan Chemical Industries Ltd., Snowtex OL; average particle diameter 40 nm) are 5% by weight of an aqueous dispersion as silica based on the resin solid content. % To make a coating solution. (Hereinafter, abbreviated as coating liquid (C-1).)

(3) Production of Laminated Polyester Film Having Covering Layer As a film raw material polymer, an intrinsic viscosity is 0.62 dl.
/ G and substantially free of particles, the PET resin pellets were dried at 135 ° C. for 6 hours under a reduced pressure of 133 Pa. After that, it was fed to a twin-screw extruder, melt-extruded into a sheet at about 280 ° C., rapidly cooled and adhered to solidify by a static electricity application method on a rotating cooling metal roll kept at a surface temperature of 20 ° C. A stretched PET sheet was obtained.

This unstretched PET sheet was heated to 100 ° C. with a heated roll group and an infrared heater, and then stretched 3.5 times in the longitudinal direction with roll groups having different peripheral speeds to obtain a uniaxially stretched PET film. It was

Next, the coating solution (C-1) was applied on both sides of the PET film by the reverse roll method so that the coating amount after drying would be 0.6 g / m ² , and then 20 ° C. at 20 ° C.
Dry for seconds. After drying, continue to 120 ° C with a tenter.
The film was stretched to 4.0 times in the width direction and the length of the film was fixed in the width direction.
For 0.5 seconds, and further subjected to 3% width relaxation treatment at 200 ° C. for 23 seconds to obtain a laminated biaxially stretched PET film having a thickness of 100 μm. The evaluation results are shown in Table 2.

Example 2 A coating solution (C) was prepared in the same manner as described above except that 15 parts by weight of maleic anhydride and 10 parts by weight of styrene were changed to 10 parts by weight of maleic anhydride, 7 parts by weight of styrene and 8 parts by weight of ethyl acrylate. -2) was obtained. The acid value of this graft is 9
It was 50 eq / t. Using this coating solution, Example 1
A laminated biaxially stretched PET film was obtained by the same method as described above. The evaluation results are shown in Table 2.

Example 3 A coating solution (C-3) was obtained in the same manner as in Example 1 except that the copolymerized polyester resin was A-2. The acid value of this graft body was 1370 eq / t. Using this coating solution, a laminated biaxially stretched PE was prepared in the same manner as in Example 1.
A T film was obtained. The evaluation results are shown in Table 2.

Example 4 The unstretched PET sheet had a thickness of 2632 μm, the biaxially stretched PET film had a thickness of 188 μm, and the drying conditions after coating were 70 ° C. for 40 seconds and 260 ° C. for 0.6 seconds. Laminated biaxially-stretched PE was prepared in the same manner as in Example 1 except that it was heat-set and then relaxed at 200 ° C. for 47 seconds for 3%.
A T film was obtained. The evaluation results are shown in Table 2.

Reference Example 1 1 part by weight of a self-crosslinking polyurethane resin having a blocked isocyanate group (Elastron H-3 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), and a catalyst for elastron to 100 parts by weight of the coating liquid (C-3). (Cat64 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.)
A laminated biaxially stretched PET film was obtained in the same manner as in Example 1 except that 1 part by weight was added. The evaluation results are shown in Table 2.

Example 5 The procedure of Example 1 was repeated except that the coating solution (C-1) was applied to only one side of the PET film by the reverse roll method.
A laminated biaxially stretched PET film was obtained in the same manner as in Example 1. The evaluation results are shown in Table 2.

Comparative Example 1 A laminated biaxially stretched PET film was obtained in the same manner as in Example 1 except that only the aqueous dispersion liquid of the copolyester resin (A-3) was used as the coating liquid (C-4). The evaluation results are shown in Table 2.

Comparative Example 2 10 parts by weight of a self-crosslinking polyurethane resin having a blocked isocyanate group (Elastron H-3, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), 100 parts by weight of the coating liquid (C-4), an elastron catalyst. (Cat64, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 1
A laminated biaxially stretched PET film was obtained in the same manner as in Example 1 except that parts by weight were added. The evaluation results are shown in Table 2.

Comparative Example 3 10 parts by weight of melamine resin (Sumimar M40W, manufactured by Sumitomo Chemical Co., Ltd.), p, based on 100 parts by weight of the coating liquid (C-4).
-Except that 0.02 parts by weight of toluenesulfonic acid was added
A laminated biaxially stretched PET film was obtained in the same manner as in Example 1. The evaluation results are shown in Table 2.

Comparative Example 4 20 parts by weight of melamine resin (Sumimar M40W, manufactured by Sumitomo Chemical Co., Ltd.), p for 100 parts by weight of the coating liquid (C-4)
-Except that 0.05 parts by weight of toluenesulfonic acid are added
A laminated biaxially stretched PET film was obtained in the same manner as in Example 1. The evaluation results are shown in Table 2.

Comparative Example 5 Acrylic copolymer resin (A-4) synthesized from methyl methacrylate, ethyl acrylate and 2-hydroxyethyl acrylate was used in place of copolymer polyester resin (A-3). In the same manner as in Comparative Example 1, a laminated biaxially stretched PET film was obtained. The acid value of this copolymer was 2 eq / t. The evaluation results are shown in Table 2.

Comparative Example 6 Example 1 was repeated except that propionic acid was not added to the coating solution.
A laminated biaxially stretched PET film was obtained in the same manner as in. The evaluation results are shown in Table 2.

Comparative Example 7 A laminated biaxially stretched PET film was obtained in the same manner as in Example 1 except that the infrared heater was not used. The evaluation results are shown in Table 2.

[0114]

[Table 2]

[0115]

According to the present invention, since a laminated polyester film having excellent adhesiveness and water resistance can be obtained, a photographic light-sensitive layer, a diazo light-sensitive layer, a mat layer, a magnetic layer, an ink layer, an adhesive layer, a heat-sensitive layer. It can be used for applications having a wide range of materials such as a cured resin layer, a UV cured resin layer, and a vapor deposition layer of metal or inorganic oxide. And since the change in the haze value after heating is small, printing applications in which heat treatment is performed in the post-processing step,
It is suitable as a base material film for optical members. further,
It is also useful in terms of economic and environmental load, since it is possible to collect a waste film that has not become a product at the time of production and reuse it as a film raw material.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP 2000-272070 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B32B 1/00-35/00 C08J 7/04

Claims (8)

(57) [Claims] 1. A polyester film having a water-soluble or water-dispersible resin and an aqueous solvent as main constituents and containing a nitrogen atom or a phenol on at least one surface thereof.
A laminated film comprising a coating layer formed by using an aqueous coating solution containing no crosslinking agent , wherein the water-soluble or
Is a water-dispersible resin made from any of the following (a) to (c):
Resin, which is an ink layer on the coating layer surface of the laminated film.
And performing pressure boil treatment at 120 ° C. for 1 hour
Perform the peeling test described in JIS-K5400 without peeling.
Area ratio of the remaining ink (water resistance value) is 90%, the
A recovery film obtained by melt extrusion molding the laminated film at 280 ° C.
The difference between the b-value of the Ret and the b-value of the laminated film before melting (discoloration value after melt molding) is 10 or less, and the laminated film is
Haze value after heating at 150 ° C for 30 minutes and before heating
The laminated polyester film , wherein the difference from the haze value of the laminated film (change in haze value after heating) is 20% or less. (A) at least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Aromatic polyester resin graft copolymer (b) containing an acrylic resin having an acid value of 200 eq / t or more, or
Is a copolymer thereof (excluding (c) ) (c) at least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Acrylic resin containing an acid value of 200 eq / t or more
Copolymer of 2. The coating solution further contains nitrogen atoms or fluorine.
The laminated polyester film according to claim 1, wherein a crosslinking agent containing no enol is used . 3. An acid compound is further used in the coating solution.
Laminated polyester film of claim 1, wherein the that. 4. The coating amount of the coating layer after drying is 0.0
1 to 1.0 g / m ² ;
2. The laminated polyester film according to 2 or 3. 5. The laminated polyester film according to claim 1, wherein the film is used for printing. 6. The laminated polyester film according to claim 1, wherein the film is used as a base film of an optical member. 7. Polyeste after unstretched or uniaxially stretched
Water-soluble or water-dispersible on at least one side of the film
Resin and water-based solvent are the main constituents, and nitrogen source
Water-based coating that does not contain cross-linking agents containing silicone or phenols
After applying the cloth liquid, dry it, and further at least uniaxially
The resin is cross-linked by stretching and heat setting.
To produce a laminated polyester film having a coated layer
Method, The laminated polyester film is coated on the surface of the coating layer.
A layer was provided, and pressure boil treatment was performed at 120 ° C. for 1 hour.
After that, the peeling test described in JIS-K5400 is performed, and peeling is performed.
The area ratio (water resistance) of the remaining ink is 90% or more,
Time obtained by melt-extruding the laminated film at 280 ° C.
Difference between b value of collected pellets and b value of laminated film before melting
(Discoloration value after melt molding) is 10 or less, and the laminated film
Haze value and heating after heating rum at 150 ° C for 30 minutes
Difference from the haze value of the laminated film before heating (after heating
Change of Iz value) is 20% or less, The water-soluble or water-dispersible resin has the following (d) to (f)
It is a resin made of either The acid compound is added to the coating liquid, or the film after stretching is filled.
Infrared heater coating with the width direction of the frame fixed
Using at least one crosslinking promoting means for heating the layer
And a method for producing a laminated polyester film. (D) At least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Graft copolymer of aromatic polyester resin containing (E) An acrylic resin having an acid value of 200 eq / t or more, or
Is a copolymer thereof (excluding (f)) (F) At least containing an acid anhydride having a double bond
5% by weight or more of radical polymer composed of one kind of monomer
Acrylic resin containing an acid value of 200 eq / t or more
Copolymer of 8. The coating liquid further contains nitrogen atoms or fluorine.
Characterized by using a cross-linking agent containing no enol
A method for producing the laminated polyester film according to claim 7.
Law.