KR101253353B1 - Polyester film for gas barrier processing and gas barrier laminated polyester film thereof - Google Patents

Abstract

An object of the present invention is to provide a polyester film for gas barrier processing, which is excellent in gas barrier properties and has high transparency and easy processing.

This invention is a polyester film for gas barrier processing in which the coating film layer was formed in the at least single side | surface of the base film which consists of polyesters, The coating film layer is based on the weight of a coating film layer, and the (A) copolyester resin is 50 80 wt%, (B) 10-30 wt% of polyvinyl alcohol, and 3-25 wt% of (C) fine particles, and the total light transmittance of the polyester film is 85% or more and haze is 1.5% or less It is a polyester film for gas barrier processing.

Gas barrier property, ease of processing, polyester film

Description

Polyester film for gas barrier processing and gas barrier laminated polyester film which consist of it {POLYESTER FILM FOR GAS BARRIER PROCESSING AND GAS BARRIER LAMINATED POLYESTER FILM THEREOF}

Patent Document 1 Japanese Patent Application Laid-Open No. 10-111500

Patent Document 2 Japanese Unexamined Patent Publication No. 2004-9362

Patent Document 3 Japanese Unexamined Patent Publication No. 2005-1242

The present invention relates to a polyester film for gas barrier processing and a gas barrier laminated polyester film comprising the same. More specifically, it has a coating film layer on at least one side of a polyester film, and improves adhesiveness with a base material layer, a planarization layer, and a gas barrier layer, and is excellent in gas barrier property, and highly transparent poly for gas barrier processing It relates to an ester film, and a gas barrier laminated polyester film made thereof, and an organic EL display substrate and an electronic paper substrate using the same.

Polyester films, especially biaxially oriented films of polyethylene terephthalate and polyethylene naphthalate, have excellent mechanical properties, heat resistance, and chemical resistance, and thus are magnetic tapes, ferromagnetic thin film tapes, photographic films, packaging films, and films for electronic parts. It is widely used as a material, such as an electrical insulation film, the film for metal laminations, the film adhering to surfaces, such as a glass display, and the protective film of various members.

Conventionally, glass substrates have been used for image display devices typified by liquid crystal displays. In recent years, image display apparatuses are required to be thinner, lighter, larger screens, degrees of freedom of shape, curved displays, and the like, and high-transparent polymer film substrates have been studied in place of heavy and brittle glass substrates.

In addition, since a liquid crystal display must employ a backlight, it is necessary to use a large number of members, whereas development is actively progressed since the self-luminous element represented by the organic EL can cope with fewer members. Also in such an organic electroluminescent display use, the fragility and weight which are one of glass defects are improved, and the demand for flexibleization is increasing. Therefore, various thermoplastic resins containing polypropylene, polyethylene terephthalate, polyethylene-2,6-naphthalate, and polycarbonate as a polymer film substrate have been studied. These polymer film substrates are generally easier to pass gas or water vapor than glass substrates. Therefore, in various image display apparatuses containing organic EL which require high gas barrier property, in order to apply a polymer film board | substrate, it is examined to laminate | stack a layer which further improves gas barrier property on a polymer film board | substrate. Specifically, various materials, film thicknesses, laminated constitutions, and the like have been studied.

For example, Patent Document 1 proposes a cured polymer layer composed of a specific silicon compound and a polyvinyl alcohol polymer. For example, Patent Document 2 discloses a polyester film having a coating layer that is excellent in transparency and excellent in adhesion to a hard coat or an adhesive. And as a polymeric binder which comprises a coating film layer, the mixture of polyester resin, an oxazoline group, and the acrylic resin which has a polyalkylene oxide chain is illustrated, It aims at mainly improving adhesiveness with a hard-coat layer. In addition, Patent Document 3 discloses that an anchor agent layer formed between a base film made of a thermoplastic resin film and a gas barrier layer contains an anchor agent and a silane coupling agent, and has an adhesive property between the base film and the gas barrier layer. It is proposed to improve the gas barrier property by increasing.

However, when used in an image display device in which elements deteriorate easily due to moisture or oxygen, such as an organic EL display or an electronic paper, the adhesion between the polyester base film and the gas barrier layer is still insufficient in these coating layers, It is a present situation that the high gas barrier property required for organic electroluminescent display and electronic paper is not acquired.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art and to provide a polyester film for gas barrier processing having a high gas barrier property and having high transparency and easy processing when a gas barrier layer is laminated. It is in doing it. Further, another object of the present invention is to provide a polyester film for gas barrier processing, which has gas barrier properties, high transparency, and ease of processing, and further maintains gas barrier properties even after high temperature heat treatment.

Another object of the present invention is to provide a gas barrier laminated polyester film having high gas barrier properties because of its high transparency, ease of processing, and high dimensional stability against humidity changes.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, the present inventors formed the coating film layer which contains a copolyester resin, a polyvinyl alcohol, and microparticles | fine-particles in the specific ratio on at least one side of the base film which consists of polyesters, When the adhesion between the base film made of polyester and the planarization layer or the gas barrier layer is increased through the coating layer, defects that become a transmission path of water vapor and oxygen are reduced, and when any stress is applied, respectively. When it became difficult to produce the defect which a crack generate | occur | produces in an interface peeling or a gas barrier layer of, it discovered that the polyester film of the high gas barrier property is obtained at the time, and the polyester film excellent also in transparency is obtained, and came to complete this invention.

That is, according to this invention, the objective of this invention is a polyester film for gas barrier processing in which the coating film layer was formed in the at least single side | surface of the base film which consists of polyester, The coating film layer is based on the weight of a coating film layer (A) copoly 50-80 weight% of ester resin, 10-30 weight% of (B) polyvinyl alcohol, and 3-25 weight% of (C) microparticles | fine-particles, and the total light transmittance of this polyester film is 85% or more, and haze It is achieved by the polyester film for gas barrier processing (claim 1) which is 1.5% or less.

Moreover, as for the polyester film for gas barrier processes of this invention, as for a preferable aspect, the heat shrinkage rate in 150 degreeC * 30 minutes is 0.1% or less in MD direction and TD direction, respectively, and the heat shrinkage rate in 200 degreeC * 10 minutes is MD It also includes an aspect including at least one of 0.2% or less in each of the direction and the TD direction.

Moreover, this invention is a laminated structure by which the gas barrier layer was laminated | stacked on the at least one coating film layer of the polyester film for gas barrier processing, or the laminated structure by which the planarization layer and the gas barrier layer were sequentially laminated | stacked on the coating layer. The gas-barrier laminated polyester film whose humidity expansion coefficient (alpha) h of MD direction and TD direction in a gas barrier laminated polyester film which has a laminated structure is 1-10 ppm /% RH, respectively is included.

 Moreover, this invention also includes the organic electroluminescent display board | substrate and electronic paper board | substrate containing such a gas barrier laminated polyester film.

The present invention also includes the following aspects.

Item 2. (A) The polyester film for gas barrier processing according to item 1, wherein the glass transition point of the copolyester resin is 20 to 90 ° C.

Item 3. (B) The polyester film for gas barrier processing according to item 1 or 2, wherein the saponification degree of polyvinyl alcohol is 74 to 90 mol%.

Item 4. (C) The polyester film for gas barrier processing according to any one of items 1 to 3, wherein the average particle diameter of the fine particles is 20 to 100 nm.

Item 5. The polyester film for gas barrier processing according to any one of items 1 to 4, wherein the coating layer further contains 1 to 20% by weight of a crosslinking agent (D).

Item 6. The polyester film for gas barrier processing according to item 5, wherein the crosslinking agent (D) is at least one member selected from the group consisting of an oxazoline group-containing polymer, a urea resin, a melamine resin and an epoxy resin.

Item 7. The polyester film for gas barrier processing according to any one of Items 1 to 6, wherein the heat shrinkage ratio at 150 ° C for 30 minutes is 0.1% or less in the MD direction and the TD direction, respectively.

Item 8. The polyester film for gas barrier processing according to any one of items 1 to 7, wherein the heat shrinkage ratio at 200 ° C for 10 minutes is 0.2% or less for each of the MD direction and the TD direction.

Item 9. The polyester film for gas barrier processing according to any one of items 1 to 8, wherein the polyester according to claim 9 is polyethylene naphthalate.

Item 10. The polyester film for gas barrier processing according to item 9, wherein the polyethylene naphthalate is 90 mol% or more of ethylene-2,6-naphthalenedicarboxylate based on the number of moles of all repeating structural units.

Item 11. The polyester film for gas barrier processing in any one of items 1-10 used as a substrate film of an organic EL display or an electronic paper.

Item 12. The gas barrier laminated polyester film in which a gas barrier layer is further laminated on at least one coating film layer of the polyester film for gas barrier processing according to any one of items 1 to 11.

Item 13. The gas barrier laminated polyester film according to Item 12, wherein the gas barrier layer is a metal oxide or a metal nitride.

Item 14. The gas barrier laminated polyester film according to Item 12 or 13, wherein the gas barrier layer contains SiO _x (1.5? _X ? 2.0) as a main component.

Item 15. The gas barrier laminated polyester film according to any one of Items 12 to 14, wherein the humidity expansion coefficients αh in the MD direction and the TD direction are 1 to 10 ppm /% RH, respectively.

Item 16. The gas barrier laminate polyester film according to any one of Items 1 to 2, wherein the water vapor transmission rate at 40 ° C and 90% RH is 0.1 g / m 2 / day or less.

Item 17. An organic EL display substrate comprising the gas barrier laminate polyester film according to any one of items 12 to 16.

Item 18. An electronic paper substrate comprising the gas barrier laminate polyester film according to any one of items 12 to 16.

Item 19. The laminated polyester film for gas barrier processing in which the planarization layer was further laminated | stacked on at least 1 coating-film layer of the polyester film for gas barrier processing in any one of Claims 1-11.

Item 20. The laminated polyester film for gas barrier processing according to item 19, wherein the planarization layer contains polyvinyl alcohol.

Item 21. An epoxy silicon compound selected from the group consisting of (a) a silicon compound having an epoxy group and an alkoxysilyl group, its (partial) hydrolyzate, its (partial) condensate, and a mixture thereof, (b) an amino group And an amino silicon compound selected from the group consisting of a silicon compound having an alkoxysilyl group, its (partial) hydrolyzate, its (partial) condensate, and a mixture thereof, and (c) a polyvinyl alcohol or a polyvinyl alcohol copolymer. The laminated polyester film for gas barrier processes of Claim 19 or 20 which is a cured polymer layer made by crosslinking reaction.

Item 22. The laminated polyester film for gas barrier processing according to any one of items 19 to 21, wherein a peeling area of the planarization layer measured by the cross-cut test method is 10% or less.

Item 23. A gas barrier laminated polyester film, wherein a gas barrier layer is further laminated on at least one planarization layer of the laminated polyester film for gas barrier processing according to any one of items 19 to 22.

Item 24. The gas barrier laminated polyester film according to item 23, wherein the gas barrier layer is a metal oxide or a metal nitride.

Item 25. The gas barrier laminate polyester film according to item 23 or 24, wherein the gas barrier layer mainly contains SiO _x (1.5 ≦ _x ≦ 2.0).

Item 26. The gas barrier laminate polyester film according to any one of items 23 to 25, wherein the humidity expansion coefficients αh in the MD direction and the TD direction are 1 to 10 ppm /% RH, respectively.

Item 27. The gas barrier laminate polyester film according to any one of items 23 to 26, wherein the water vapor transmission rate at 40 ° C and 90% RH is 0.1 g / m 2 / day or less.

Item 28. An organic EL display substrate comprising the gas barrier laminate polyester film according to any one of items 23 to 27.

Item 29. An electronic paper substrate comprising the gas barrier laminate polyester film according to any one of items 23 to 27.

According to the present invention, the polyester film for gas barrier processing of the present invention has a high gas barrier property when the gas barrier layer is additionally formed, and also has high transparency and diactivity. It can be used suitably as substrate films, such as this organic electroluminescent display and electronic paper which are requested | required. Moreover, since the gas barrier laminated polyester film of this invention has a high gas barrier property, and has high transparency and dilution, it can be used suitably as an organic electroluminescent display board | substrate and an electronic paper substrate which require these characteristics. have.

Carrying out the invention  Best form for

Hereinafter, the present invention will be described in detail.

<Base film>

The base film of this invention is comprised by polyester. As polyester of this invention, aromatic polyester synthesize | combined from aromatic dicarboxylic acid or its ester formable derivative, and diol or its ester formable derivative can be used. As an aromatic dicarboxylic acid component, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 4,4'- diphenyl dicarboxylic acid is illustrated, for example, As a diol component, For example, ethylene glycol, 1,3 -Propanediol, 1,4-butanediol, 1,4-cyclohexanedimethanol, 1,6-hexanediol are exemplified. Specific examples of the polyester of the present invention include polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, poly (1,4-cyclohexylenedimethylene terephthalate), polyethylene naphthalate and polytrimethylene Phthalates are illustrated. In particular, polyethylene terephthalate and polyethylene naphthalate are preferred in terms of balance of mechanical and optical properties, and polyethylene naphthalate is most preferred in terms of heat resistance expressed by gas barrier properties and heat shrinkage. The polyester may be any of a homopolymer, a copolymer obtained by copolymerizing a third component, and a polymer blend.

When polyester is polyethylene naphthalate, naphthalenedicarboxylic acid is used as a main dicarboxylic acid component, and ethylene glycol is used as a main diol component. Examples of the naphthalene dicarboxylic acid include 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid and 1,5-naphthalene dicarboxylic acid. Of these, 2,6-naphthalene dicarboxylic acid Acids are preferred. Here, "main" means at least 90 mol%, preferably at least 95 mol% of all the repeating units constituting the polyester.

When polyethylene naphthalate is a copolymer, as a copolymerization component which comprises a copolymer, for example, oxalic acid, adipic acid, phthalic acid, sebacic acid, dodecanedicarboxylic acid, isophthalic acid, terephthalic acid, 1,4-cyclo Hexanedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, phenylindandicarboxylic acid, 2,7-naphthalenedicarboxylic acid, tetralin dicarboxylic acid, decalin dicarboxylic acid, diphenyl Dicarboxylic acids such as ether dicarboxylic acid and the like; oxycarboxylic acids such as p-oxybenzoic acid and p-oxyethoxybenzoic acid; Or diols such as trimethylene glycol, tetramethylene glycol, hexamethylene glycol, cyclohexane methylene glycol, neopentiglycol, ethylene oxide adducts of bisphenol sulfone, ethylene oxide adducts of bisphenol A, diethylene glycol, and polyethylene oxide glycol. It can be used preferably. You may use these copolymerization components 1 type, or 2 or more types. Among these copolymerization components, preferred acid components are isophthalic acid, terephthalic acid, 4,4'-diphenyldicarboxylic acid, 2,7-naphthalenedicarboxylic acid, and p-oxybenzoic acid. Ethylene oxide adducts of trimethylene glycol, hexamethylene glycol, neopentiglycol, and bisphenol sulfone.

When polyethylene naphthalate is a polymer blend, as a blend component, polyethylene terephthalate, polyethylene isophthalate, polytrimethylene terephthalate, polyethylene-4,4'- tetramethylene diphenyl dicarboxylate, polyethylene-2,7- Naphthalenedicarboxylate, polytrimethylene-2,6-naphthalenedicarboxylate, polyneopentylene-2,6-naphthalenedicarboxylate, poly (bis (4-ethyleneoxyphenyl) sulfone) -2, Polyester, such as 6-naphthalenedicarboxylate, is mentioned. You may use these blend components 1 type or 2 or more types.

In addition, the polyester of the present invention may be one in which some or all of the terminal oxalic acid group and / or carboxyl group are sealed by a monofunctional compound such as benzoic acid or methoxypolyalkylene glycol. Moreover, what copolymerized within the range from which a linear polymer is obtained substantially with trifunctional or more than trifunctional ester forming compound, such as glycerin and pentaerythritol, may be sufficient.

The polyester of the present invention is a conventionally known method, for example, a method of directly obtaining a low degree of polymerization polyester by reaction of dicarboxylic acid and diol, or a lower alkyl ester of dicarboxylic acid and a diol. For example, sodium, potassium, magnesium, calcium, zinc, strontium, titanium, zirconium, manganese, reacted with one or two or more kinds of compounds containing cobalt, followed by polymerization in the presence of a polymerization catalyst. You can get it by Examples of the polymerization catalyst include antimony trioxide and antimony compounds such as antimony pentoxide, germanium compounds represented by germanium dioxide, tetraethyl titanate, tetrapropyl titanate, tetraphenyl titanate or partial hydrolyzate thereof, and titanium oxalate Titanium compounds, such as ammonium, titanyl potassium oxalate, and titanium tris acetylacetonate, can be used.

When the polymerization is carried out via a transesterification reaction, trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, positive phosphoric acid or the like is usually used for the purpose of deactivating the transesterification catalyst prior to the polymerization reaction. Phosphorus compound of is added. It is preferable that a phosphorus compound is 20-100 ppm in content in polyester as a phosphorus element from the viewpoint of the thermal stability of polyester.

In addition, polyester may chip this after melt polymerization, and may perform ê * phase polymerization further under heating reduced pressure, or in inert airflow, such as nitrogen.

It is preferable that it is 0.40 dl / g or more, and, as for the intrinsic viscosity of polyester, it is more preferable that it is 0.40 to 0.90 dl / g. When intrinsic viscosity is less than 0.40 dl / g, cutting | disconnection may be frequent in a film film forming process. In addition, when the intrinsic viscosity is higher than 0.90 dl / g, melt extrusion is difficult because the melt viscosity is high, and the polymerization time is long, which is uneconomical. Moreover, it is preferable that it is 0.38-0.85 dl / g, and, as for the intrinsic viscosity of the polyester after film forming with a biaxially oriented film, it is more preferable that it is 0.40-0.80 g / dl. In addition, intrinsic viscosity is the value measured at 35 degreeC using o-chlorophenol as a solvent.

It is preferable that the base film of this invention does not contain the microparticles | fine-particles used as a lubricant.

The base film of the present invention has a Young's modulus of 4.5 in both the MD direction (hereinafter may be referred to as a continuous film forming direction, the longitudinal direction and the longitudinal direction) and the TD direction (hereinafter may be referred to as the width direction and the horizontal direction). It is preferable that it is GPa or more. When the Young's modulus of a base film is less than a lower limit, regarding the humidity expansion coefficient mentioned later, even if the part of a coating film layer and a gas barrier layer is appropriate, the humidity expansion coefficient (alpha) h as laminated | multilayer film cannot be made into the range of 10 ppm /% RH or less. have. As a specific means for making the Young's modulus of a base film into 4.5 GPa or more in both MD direction and a TD direction, what extends to a MD direction and a TD direction by the magnification of 2.9 times or more is mentioned. On the other hand, when the upper limit of the Young's modulus of a base film improves temperature change, especially the dimensional stability in the high temperature range of 200 degreeC, and maintains high gas barrier property even after receiving such a thermal history, MD direction and TD It is preferable that both directions are 7.0 GPa or less. When the Young's modulus of a base film exceeds an upper limit, heat-resistant dimensional stability at 200 degreeC is bad, and as a result, a fracture occurs by a crack in a gas barrier layer, etc. As a result, gas barrier property may fall after receiving a thermal history. As a specific means for making the Young's modulus of a base film into 7.0 GPa or less in both MD direction and TD direction, what extends to a MD direction and a TD direction at the magnification of 3.9 times or less is mentioned.

 It is preferable that the thickness of a base film is 12-500 micrometers in order to acquire the intensity | strength and flexibility required when using it as support bodies, such as an organic electroluminescent display, an electronic paper, a liquid crystal display, a solar cell, and an organic TFT. The thickness of the base film in the case of using as a support body of an electronic paper is 12-50 micrometers as a more preferable range, Especially preferably, it is 12-25 micrometers. Moreover, the thickness of the base film in the case of using it as support bodies, such as an organic electroluminescent display, a liquid crystal display, a solar cell, an organic TFT, becomes like this. More preferably, it is 25-350 micrometers, Especially preferably, it is 50-250 micrometers. When the thickness of the base film is less than the lower limit, in the layer structure including the coating layer and the gas barrier layer on one side of the base film, the effect of reducing the diffusion rate of water vapor due to the layer structure is not sufficiently expressed. It may exceed the upper limit and gas barrier property may fall.

The thicker the thickness of the base film, the easier the effect of reducing the diffusion rate of water vapor due to the layer structure becomes. However, since thinning is required for the base film within a range that satisfies the flexibility and characteristics, the upper limit of the thickness of the base film is preferably in the above-described range.

<Film layer>

The base film which consists of polyester of this invention has the coating film layer containing the following (A)-(C) at least on single side | surface. A coating film layer is obtained by drying, after apply | coating the coating liquid containing (A)-(C) on a base film.

(A) 50-80 wt% of copolyester resin

(B) 10 to 30% by weight of polyvinyl alcohol

(C) 3 to 25 wt% of fine particles

Here, the weight of a coating film layer is the same as solid content contained in a coating liquid. Content of each component (A)-(C) is content which made the weight of a coating film layer 100 weight%.

Since the coating film layer of this invention is comprised from the said component, the base film which consists of polyester through the coating film layer, and a flattening layer (when the flattening layer is laminated | stacked on the coating film layer) or a gas barrier layer (coating layer) The adhesiveness with the case where the gas barrier layer is laminated | stacked on it becomes high. As a result, when the gas barrier layer is further laminated, the gas barrier property is excellent in transparency and film formability.

In particular, as a remarkable effect of each component paying attention to gas barrier properties, (A) the copolyester component has an effect of enhancing the adhesiveness with the polyester base layer, and (B) the polyvinyl alcohol component has a flattening layer or a gas barrier layer. It has the effect of improving the adhesiveness with. In addition, as described in detail below, the content of each component also contributes to the gas barrier performance.

<Copolyester resin>

Copolyester resin (A) which forms a coating film layer is a copolyester which consists of polybasic acid or its ester forming derivative, polyol or its ester forming derivative, and was synthesize | combined using at least 2 acid component. When a copolyester resin is used, adjustment of a glass transition point and crystallization temperature can be performed easily.

It is preferable that a copolyester resin (A) is a copolyester resin in which the glass transition point exists in 20-90 degreeC. When a glass transition point is less than 20 degreeC, films are easy to block, and when it exceeds 90 degreeC, the chipping property of a film may fall, a coating film layer may become weak, and adhesiveness may not be maintained.

 As a structural component of the polyester resin which has such a glass transition point, the following can be used. That is, the main polybasic acid components are terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, phthalic acid, phthalic anhydride, 1,4-cyclohexanedicarboxylic acid, adipic acid, sebacic acid, trimellitic acid, and fatigue Mellitic acid, dimer acid, etc. are mentioned. In addition, very small amounts of hydroxycarboxylic acids such as maleic acid, itaconic acid and the like and p-hydroxybenzoic acid of the unsaturated polybasic acid component can be used. Moreover, as a polyol component, ethylene glycol, diethylene glycol, dipropylene glycol, 1, 4- butanediol, 1, 6- hexanediol, 1, 4- cyclohexane dimethanol, xylene glycol, dimethylol propane, trimethylol propane And glycerin, poly (ethylene oxide) glycol, poly (tetramethylene oxide) glycol, and alkylene oxide adducts of bisphenol-A.

The copolyester resin (A) may use a dicarboxylic acid component having a sulfonic acid base in order to impart hydrophilicity. Examples of the dicarboxylic acid component having a sulfonic acid base include 5-sodium sulfoisophthalic acid, 5-potassium sulfoisophthalic acid, 5-potassium sulfoterephthalic acid, and the like. The dicarboxylic acid component having a sulfonic acid base is preferably 1 to 16 mol% copolymerized with respect to all the acid components in the molecule, more preferably 1.5 to 14 mol%. When the dicarboxylic acid component having a sulfonic acid base is less than the lower limit, the hydrophilicity of the copolyester resin may be insufficient. On the other hand, when the upper limit is exceeded, the moisture resistance of the coating layer may decrease, resulting in insufficient gas barrier properties. .

Content of copolyester resin (A) is 50-80 weight% based on the weight of a coating film layer. When content of a copolyester resin is less than 50 weight%, adhesiveness with a polyester film runs short, and when it exceeds 80 weight%, adhesiveness with a planarization layer or a gas barrier layer falls. Therefore, when content of a copolyester resin (A) exceeds this range, the humidity expansion coefficient (alpha) h of laminated | multilayer film exceeds the upper limit, and sufficient gas barrier performance is not obtained.

<Polyvinyl alcohol>

As polyvinyl alcohol (B) which forms a coating film layer, polyvinyl alcohol or its copolymer is used. Examples of the polyvinyl alcohol copolymers include vinyl alcohol-vinyl acetate copolymers, vinyl alcohol-vinyl butyral copolymers, ethylene-vinyl alcohol copolymers, and polyvinyl alcohol polymers having a silyl group in the molecule. Among these, vinyl alcohol- Vinyl acetate copolymer and ethylene-vinyl alcohol copolymer are preferable. Usually, the copolymerization ratio of vinyl alcohol is represented by saponification degree. It is preferable that the polyvinyl alcohol (B) of this invention is 74-90 mol% in saponification degree. When the saponification degree is less than 74 mol%, the moisture resistance of a coating film layer may fall and gas barrier property may become inadequate. On the other hand, when saponification degree exceeds 90 mol%, adhesiveness and blocking resistance to a planarization layer or a gas barrier layer may fall.

Content of polyvinyl alcohol (B) is 10-30 weight% based on the weight of a coating film layer. When content of polyvinyl alcohol is less than 10 weight%, adhesiveness with a planarization layer or a gas barrier layer is not fully acquired. On the other hand, when content of polyvinyl alcohol exceeds 30 weight%, blocking resistance falls or moisture resistance falls and gas barrier property becomes inadequate.

<Particulates>

The microparticles | fine-particles (C) which form a coating layer may be any of organic and inorganic, calcium carbonate, calcium oxide, aluminum oxide, kaolin, silicon oxide, zinc oxide, crosslinked acrylic resin particle, crosslinked polystyrene resin particle, melamine resin particle, Crosslinked silicone resin particles are exemplified. It is preferable that the microparticles | fine-particles (C) of this invention are 20-100 nm in average particle diameter. When the average particle diameter of microparticles | fine-particles is less than 20 nm, it will become easy to block films, and when it exceeds 100 nm, shaving property may fall or adhesiveness with a planarization layer or a gas barrier layer may fall.

Content of microparticles | fine-particles (C) is 3-25 weight% based on the weight of a coating film layer. If the content of the fine particles is less than 3% by weight, the activity (transportability) of the film is insufficient, while if the content is more than 25% by weight, the haze decreases, or the adhesiveness and chipping with the planarization layer or the gas barrier layer decreases. The gas barrier properties are insufficient.

<Bridge school>

The coating film layer of this invention may contain 1-20 weight% of (D) crosslinking agents further. By containing a crosslinking agent, gas barrier property can be improved further. As a crosslinking agent (D) which forms a coating film layer, it is preferable to use at least 1 sort (s) chosen from the group which consists of an oxazoline group containing polymer, urea resin, melamine resin, and epoxy resin. When the content of the crosslinking agent is less than 1% by weight, the blocking property of the coating layer may be insufficient, and the improvement of gas barrier properties may be insufficient. On the other hand, when the content of the crosslinking agent exceeds 20% by weight, the formation of the coating film may be difficult. May not be sufficiently obtained, resulting in insufficient gas barrier properties.

Specifically as an oxazoline group containing polymer, the addition polymerizable oxazoline (a) represented by following formula (I), and the polymer obtained by superposing | polymerizing another monomer (b) as needed are mentioned.

(In formula, R <^1> , R <^2> , R <^3> and R <^4> represent a substituent selected from the group which consists of a hydrogen, a halogen, an alkyl group, an aralkyl group, a phenyl group, and a substituted phenyl group, respectively, and R <^5> is an addition polymeric unsaturated bond group. A non-cyclic organic group having

As a specific example of the addition polymeric oxazoline (a) represented by said formula (I), 2-vinyl-2- oxazoline, 2-vinyl-4-methyl-2- oxazoline, 2-vinyl-5- Methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, etc. are mentioned. These can be used as 1 type, or 2 or more types of mixtures. Of these, 2-isopropenyl-2-oxazoline is preferable because it is easily obtained industrially.

The monomer (b) other than the addition polymerizable oxazoline is not particularly limited as long as it is a monomer copolymerizable with the addition polymerizable oxazoline (a). Examples thereof include acrylic acid esters such as methyl (meth) acrylate and butyl (meth) acrylate. , Unsaturated carboxylic acids such as acrylic acid, methacrylic acid and itaconic acid, unsaturated nitriles such as acrylonitrile and methacrylonitrile, and unsaturated amides such as (meth) acrylamide and N-methylol (meth) acrylamide Vinyl esters such as vinyl acetate and vinyl propionate, vinyl ethers such as methyl vinyl ether and ethyl vinyl ether, α-olefins such as ethylene and propylene, halogen-containing α- and β-unsaturated monomers such as vinyl chloride, (Alpha), (beta)-unsaturated aromatic monomers, such as styrene, etc. are mentioned. These can be used as 1 type, or 2 or more types of mixtures.

When a polymer is obtained using the addition polymerizable oxazoline (a) and at least one other monomer (b), the blending amount of the addition polymerizable oxazoline (a) is suitably determined in a range of 0.5% by weight or more based on the total monomers. It is preferable. When the compounding quantity of an addition polymeric oxazoline (a) is less than 0.5 weight%, it may become difficult to achieve the objective of this invention.

  Specifically as an epoxy resin, a polyepoxy compound, a diepoxy compound, a monoepoxy compound, etc. are mentioned. As a polyepoxy compound, for example, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, triglycidyl tris (2-hydroxy) Ethyl) isocyanate, glycerol polyglycidyl ether, trimethylolpropanepolyglycidyl ether, N, N, N ', N'-tetraglycidylmethazylylenediamine, N, N, N', N'-tetra Glycidyl-4,4'- diaminodiphenylmethane, N, N, N ', N'- tetraglycidyl-1,3-bisaminomethylcyclohexane, etc. are mentioned.

As the diepoxy compound, for example, neopentiglycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, resorcinol diglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol digly Cylyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, etc. are mentioned.

Moreover, as a mono epoxy compound, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, etc. are mentioned, for example.

Especially, N, N, N ', N'- tetraglycidyl meta xylylenediamine, N, N, N', N'- tetraglycidyl-4,4'- diamino diphenylmethane, N, N, N ', N'-tetraglycidyl-1,3-bisaminomethylcyclohexane is preferably exemplified.

As urea-type resin, dimethylol urea, dimethylol ethylene urea, dimethylol propylene urea, tetramethylol acetylene urea, 4-methoxy 5- dimethyl propylene urea dimethylol, etc. are mentioned preferably, for example.

Examples of the melamine resins include compounds obtained by etherification of methylol melamine derivatives obtained by condensing melamine with formaldehyde and etherification of methyl alcohol, ethyl alcohol, isopropyl alcohol and the like as lower alcohols, and mixtures thereof. Examples of the methylolmelamine derivatives include monomethylolmelamine, dimethylolmelamine, trimethylolmelamine, tetramethylolmelamine, pentamethylolmelamine, hexamethylolmelamine, and the like.

Among these crosslinking agents (D), epoxy resins, particularly polyepoxy compounds, are preferable. These crosslinking agents may be used alone or in combination of two or more in some cases.

Moreover, it is preferable that the surface energy of the coating film layer of this invention is 50-65 dyne / cm, and it is especially preferable that it is 55-62 dyne / cm. When this surface energy is less than a lower limit, the coating property and adhesiveness of a planarization layer may become poor. On the other hand, when the surface energy of a coating film layer exceeds an upper limit, adhesiveness with the base film which consists of polyester may be insufficient, or the moisture resistance of a coating film layer may be insufficient. In order to obtain the coating film layer which has such surface energy, (A) copolyester resin, (B) polyvinyl alcohol, (C) microparticles | fine-particles, and (D) crosslinking agent are respectively mix | blended in the range mentioned above, These (A) It is achieved by apply | coating and forming in thickness of 0.02-1 micrometer, for example using the coating liquid containing (D) component. The coating forming method may be any of a method of forming a coating in the stretching step at the time of film forming and a method of coating forming after the film stretching, but in the film forming step from the viewpoint of adhesiveness to the polyester film of the coating film The method of forming is preferable.

Moreover, you may use antistatic agent, a coloring agent, surfactant (wetting agent), a ultraviolet absorber, etc. other than said component as a component which forms a coating film layer in the range which does not impair the subject of this invention.

<Total light transmittance>

The polyester film for gas barrier processing of this invention needs to be 85% or more of the total light transmittance measured based on JIS standard K7105. When the total light transmittance is less than 85%, the transparency deteriorates, so that the luminance decreases when used for display. The total light transmittance is more preferably 87% or more, particularly preferably 90% or more. In order to make total light transmittance into the above-mentioned range, it is necessary not to contain a filler in a board | substrate film, and also to form the coating film layer containing (A)-(C) component at least on one side, preferably both surfaces, The light transmittance is further improved.

<Hayes>

It is necessary for the polyester film for gas barrier processes of this invention that the haze measured based on JIS standard K7105 is 1.5% or less. If the haze exceeds 1.5%, the transparency deteriorates, and when used for display, the display screen appears white and the contrast decreases. Haze is more preferably 1.0% or less, particularly preferably 0.5% or less. In order to make haze into the above-mentioned range, it is necessary not to contain a filler in a board | substrate film, and it is achieved by a coating film layer containing (A)-(C) component.

<Heat shrinkage rate>

It is preferable that the thermal contraction rate in 150 degreeC x 30 minutes of the polyester film for gas barrier processes of this invention is 0.1% or less in MD direction and TD direction, respectively. When the heat shrinkage ratio exceeds the upper limit, when the various functional layers including the gas barrier layer are laminated on the polyester base film or after lamination, cracks or wrinkles occur in the functional layer under a high-temperature atmosphere around 150 ° C. As a result of this, the functional layer may be broken, and the function including gas barrier property may not be sufficiently expressed. The heat shrinkage rate at 150 ° C. for 30 minutes is more preferably 0.05% or less, particularly preferably 0.03% or less.

In order to make the heat shrinkage rate in 150 degreeC into the above-mentioned range, in the film forming process of a polyester film, after extending | stretching each lengthwise and horizontal direction, it is 1 at the temperature of (Tm-100)-(Tm-5) degreeC. It is achieved by performing heat setting for ˜100 seconds and then performing a relaxation treatment at a temperature of (X-80) to X ° C. Tm is melting | fusing point and X is heat setting temperature here, respectively.

Moreover, it is preferable that the thermal contraction rate in 200 degreeC * 10 minutes of the polyester film for gas barrier processes of this invention is 0.2% or less in MD direction and TD direction, respectively. By the heat shrinkage rate in 200 degreeC x 10 minutes of a polyester base film in these ranges, high gas barrier property is maintained even after receiving the heat history of 200 degreeC vicinity. When the heat shrinkage ratio exceeds the upper limit, when the various functional layers including the gas barrier layer are laminated on the polyester film, or after lamination, there is a work process in a high-temperature atmosphere around 200 ° C. As a result of wrinkles or wrinkles, the functional layer may be broken so that a function including gas barrier properties may not be sufficiently expressed. The heat shrinkage rate at 200 ° C. for 10 minutes is more preferably 0.1% or less, and particularly preferably 0.05% or less.

In order to make the heat shrinkage rate in 200 degreeC into the above-mentioned range, in the film forming process of a polyester film, it extends | stretches longitudinally and horizontally at 3.9 times or less, respectively (Tm-100)-(Tm-5) It is achieved by performing heat setting at a temperature of 1 ° C. for 1 to 100 seconds and then performing a relaxation treatment at a temperature of (X-80) to X ° C .. The base film in which the thermal contraction rate in 200 degreeC exists in such a range also has a Young's modulus of 7.0 GPa or less simultaneously.

<Flattening layer>

According to this invention, the laminated polyester film for gas barrier processing which further provided the planarization layer was laminated | stacked on the at least 1 coating film layer of the polyester film for gas barrier processing in order to improve gas barrier property. The type and method of forming the layer are not particularly limited as long as the planarization layer in the present invention has a function of leveling the surface and bringing the layers into close contact. By laminating the gas barrier layer on the base film via the coating film layer and the planarization layer, the defect that causes gas permeation can be reduced. The effect of the planarization layer on the gas barrier property is to planarize the surface so that defects such as pinholes and cracks do not easily occur in the gas barrier layer, and because the adhesion between the coating layer and the planarization layer is high, It can mention the thing which can reduce the fault which arises. As a result, when a planarization layer is included, humidity expansion coefficient (alpha) h is excellent and gas barrier property improves.

It is preferable to form a planarization layer by application | coating, and it may be called a primer layer and an anchor layer in some cases. Examples of the planarization layer include thermosetting resins such as silicon-containing resins and epoxy resins, radiation-curable resins such as ultraviolet curable acrylic resins, melamine resins, urethane resins, alkyd resins, polyacrylonitrile, and acrylonitrile-methyl acrylate. Acrylonitrile copolymers, such as a copolymer and an acrylonitrile- styrene copolymer, polyvinylidene chloride, vinyl alcohol, and its copolymer are illustrated, It is preferable to use the coating composition containing at least one of these.

Among these, since the adhesiveness with a coating film layer becomes higher, the planarization layer containing a silicon containing resin, polyvinyl alcohol, and its copolymer is preferable. As a more preferable planarization layer, (a) the silicon compound which has an epoxy group and the alkoxy silyl group, its (partial) hydrolyzate, its (partial) condensate, and an epoxy silicon type compound chosen from the group which consists of these mixtures, (b) an amino group And an amino silicon compound selected from the group consisting of a silicon compound having an alkoxysilyl group, its (partial) hydrolyzate, its (partial) condensate, and a mixture thereof, and (c) a polyvinyl alcohol or a polyvinyl alcohol copolymer. The cured polymer layer formed by crosslinking reaction is mentioned. As a planarization layer, when the cured polymer which crosslinks-reacts (a)-(c) component is used, it is excellent in surface smoothness, adhesiveness with an application layer, and a gas barrier layer, durability, plasticity, and gas barrier property further improves. do.

(a) The silicon compound which has an epoxy group and the alkoxy silyl group, for example, is following General formula (II)

(Wherein R ⁶ is an alkylene group having 1 to 4 carbon atoms, R ⁷ and R ⁸ are an alkyl group having 1 to 4 carbon atoms, X is a glycidoxy group or an epoxycyclohexyl group, n is 1 or 0)

And the like.

Among the silicon compounds having an epoxy group and an alkoxysilyl group represented by General Formula (II), 3-glycidoxypropyltrimethoxysilane and (3,4-epoxycyclohexyl) ethyltrimethoxysilane are particularly preferable. These compounds can be used individually or in combination of 2 or more types.

 The (partial) hydrolyzate of the silicon compound which has an epoxy group and the alkoxy silyl group is a part or whole hydrolysis of such a silicon compound. The (partial) condensate is a condensate obtained by condensation of a part or all of the hydrolyzate of the silicon compound and a silicon compound of a raw material which is not hydrolyzed with the condensate. It is obtained by making it.

(b) The silicon compound which has an amino group and the alkoxy silyl group, for example, is following General formula (III)

(Wherein R ⁹ is an alkylene group having 1 to 4 carbon atoms, R ¹⁰ and R ¹¹ are an alkyl group having 1 to 4 carbon atoms, Y is a hydrogen atom or an aminoalkyl group, m is 1 or 0) Can be mentioned.

Among the silicon compounds having an amino group and an alkoxysilyl group represented by General Formula (III), 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, 3-aminopropylmethyldiethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane and N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane are preferable. These compounds can be used individually or in combination of 2 or more types.

The (partial) hydrolyzate of the silicon compound which has an amino group and the alkoxy silyl group is a part or whole hydrolysis of such a silicon compound. The (partial) condensate is a condensation product of a condensate obtained by condensation reaction of part or all of the hydrolyzate of the silicon compound, and a silicon compound of a raw material that is not hydrolyzed with the condensate.

The polyvinyl alcohol or its copolymer in description of the (B) polyvinyl alcohol component of a coating film layer can be used for (c) polyvinyl alcohol or a polyvinyl alcohol copolymer. Examples of the polyvinyl alcohol copolymers include vinyl alcohol-vinyl acetate copolymers, vinyl alcohol-vinyl butyral copolymers, ethylene-vinyl alcohol copolymers, and polyvinyl alcohol polymers having a silyl group in the molecule. Among these, vinyl alcohol- The vinyl acetate copolymer, the ethylene-vinyl alcohol copolymer, and the polyvinyl alcohol polymer having a silyl group in the molecule are preferable, and the ethylene-vinyl alcohol copolymer is particularly preferable.

Usually, it is preferable that the copolymerization ratio of vinyl alcohol is represented by a saponification degree, and (c) component has a saponification degree of 74-90 mol%. When the saponification degree is less than 74 mol%, the moisture resistance of the planarization layer may fall, and gas barrier property may become inadequate. On the other hand, when saponification degree exceeds 90 mol%, the adhesiveness and blocking resistance to a coating film layer and a gas barrier layer may fall.

In addition, the polyvinyl alcohol-type polymer which has a silyl group in a molecule | numerator has a reactive alkoxy silyl group represented by following General formula (IV).

(In the formula, R ¹² represents hydrogen or an alkyl group having 1 to 10 carbon atoms, an acyl group, or an alkali metal or an alkaline earth metal, R ¹³ represents an alkyl group having 1 to 10 carbon atoms, and p represents an integer of 1 to 3). )

The content of the silyl group is preferably 5 mol% or less, more preferably 1 mol% or less. When the content of the silyl group increases, the coating agent forming the planarization layer tends to gel. In addition, "in a molecule" means the terminal of a high molecular polymer, and if a silyl group couple | bonds with a polyvinyl alcohol-type polymer by the bond which is not hydrolyzable, there is no restriction | limiting in particular in the position, distribution state, etc.

It is preferable that the content rate of (a)-(c) component is a weight ratio represented by following formula (1).

1/9 <(c) / {(a) + (b)} <9/1... (One)

The weight of each component is determined assuming that all of the alkoxysilyl groups in the respective silicon compounds undergo condensation reaction after hydrolysis.

When the content rate of (a)-(c) component exceeds the upper limit of Formula (1), water resistance and chemical resistance may fall. On the other hand, when the content rate of (a)-(c) component is less than the lower limit of Formula (1), gas barrier property may not fully improve.

Moreover, it is preferable that the content rate of (a) component and (b) component is a weight ratio represented by following formula (2) from a viewpoint of adhesiveness, heat resistance, solvent resistance, water resistance, durability, etc.

1/6 <(a ') / (b') <6/1... (2)

(In the formula, (a ') represents the molar equivalent conversion amount of the epoxy group contained in (a) component, (b') shows the total molar equivalent conversion amount of the amino group and imino group contained in (b) component.)

In the cured polymer formed by crosslinking the components (a) to (c), a curing catalyst may be added as necessary at the time of crosslinking.

It is preferable that a planarization layer is formed by application | coating, for example, in the case of the cured polymer formed by crosslinking-reacting (a)-(c) component, for coating containing each component of (a)-(c) and a solvent It can form by apply | coating a composition on a coating layer and heat-hardening. As a coating method, the method currently used, such as a dip coat, a spray coat, a flow coat, a roll coat, a bar coat, a spin coat, is illustrated.

As for the film thickness of a planarization layer, 0.01-100 micrometers is preferable. Especially in the case of a cured polymer, curing takes time when the film thickness exceeds 100 µm.

It is preferable that the peeling area of the planarization layer measured by the cross cut test method of the planarization layer of this invention is 10% or less. Here, the peeling area of the planarization layer measured by the crosscut test method cross-cuts 100 grids of 1 mm <2> and a checkerboard eye shape on a planarization layer, and the cellophane tape of 24 mm width (niche reflection) on it. Manufactured trademark), and after peeling off at 180 degree peeling angle rapidly, a peeling surface is observed and it is defined as the value calculated | required by (number / 100 of peeled lattice scales) x100.

In addition, in this evaluation method, since the planarization layer and the coating film layer are cut | disconnected, it peels at the interface with a weaker adhesive force between a base material-coating layer and between coating-film layer-flattening layers. Therefore, after an peeling test, it shall be judged which interface is peeled off by an optical microscope.

When the peeling area of a planarization layer exceeds an upper limit, the adhesiveness of the base film through a coating film layer and a planarization layer may not be enough, and sufficient gas barrier property may not be obtained. On the other hand, the smaller the lower limit, the better the adhesion between the coating layer and the planarization layer, and a good gas barrier property is obtained, and usually at least 0%.

As means for achieving the peeling area in the above-described range, as the planarization layer, a high adhesiveness with the coating layer, for example, silicon-containing resin and polyvinyl alcohol and its copolymer, particularly preferably It is achieved by using the cured polymer formed by crosslinking-reacting (a)-(c) component.

<(Laminated) Polyester Film and Gas Barrier Laminated Polyester Film for Gas Barrier Processing>

The (laminated) polyester film for gas barrier processing in this invention refers to the polyester film of the laminated constitution of a step before a gas barrier layer is laminated | stacked. Specifically, the layer structure in which the coating film layer was formed in the at least single side | surface of the base film which consists of polyester is called the polyester film for gas barrier processes. Moreover, in the case of the laminated constitution which has a coating film layer and a planarization layer in the at least single side | surface of the base film which consists of polyester, it is called the laminated polyester film for gas barrier processes. In the case of these laminated constitutions, the (laminated) polyester film for gas barrier processing itself does not have sufficient gas barrier properties as an organic EL display substrate or an electronic paper substrate, but is further described later in the (laminated) polyester film for gas barrier processing. When the barrier layer is formed, excellent water vapor gas barrier properties, which are not available in the past, can be expressed, and in the present invention, the laminated polyester film containing the gas barrier layer is referred to as a gas barrier laminated polyester film.

<Gas barrier layer>

In the present invention, in order to further improve the gas barrier property, a gas barrier laminated polyester film in which a gas barrier layer is laminated on at least one coating layer or at least one planarization layer can be used. As such a gas barrier layer, a metal oxide or metal nitride is exemplified.

Examples of the metal oxides include zinc oxide, silicon oxide, aluminum oxide, magnesium oxide, titanium oxide, indium oxide, tin oxide, indium tin oxide (ITO), titanium oxide, zirconium oxide, and nidium oxide. You may use one type or a combination of them. Among these metal oxides, zinc oxide, silicon oxide, aluminum oxide and magnesium oxide are preferable, and silicon oxide is particularly preferable in terms of gas barrier properties and adhesiveness. These metal compounds may further contain at least one metal selected from the group consisting of iron, nickel, chromium, titanium, indium, tin, antimony, tungsten, molybdenum and copper as auxiliary components. Moreover, you may contain carbon and fluorine suitably for the purpose of improving the flexibility and transparency of a film | membrane. The main component may be added in the range of 70% by weight or more based on the weight of the gas barrier layer and the auxiliary component in the range of 30% by weight or less based on the weight of the gas barrier layer.

The composition of silicon oxide is analyzed and determined by X-ray photoelectron spectroscopy, X-ray microscopy, Auger electron spectroscopy, Rajahord backscattering, or the like. In view of transmittance, flexibility, and the like, in the average composition represented by SiOx, x is preferably in a range of 1.5 or more and 2.0 or less. When x is smaller than 1.5, flexibility and transparency may fall.

Examples of the metal nitrides include aluminum nitride, silicon nitride, and boron nitride, and may be used alone or in combination.

The gas barrier layer is formed by a known sputtering method, vacuum deposition method, ion plating method, plasma CVD method, or the like. In particular, the sputtering method can freely change the oxidation degree of a metal oxide, and also has the advantage that the change in film composition is small over a long time, and the film thickness uniformity and surface flatness are excellent.

The thickness of the metal oxide layer is preferably in the range of 2 to 200 nm. If the thickness of the metal oxide layer is less than 2 nm, it is difficult to form a film uniformly, and a portion where the film is not formed may occur, thereby impairing the gas barrier property. On the other hand, when thickness exceeds 200 nm, transparency and flexibility may fall, a crack may arise and gas barrier property may be impaired.

Humidity Expansion Coefficient αh

It is preferable that humidity expansion coefficient (alpha) h of MD direction and TD direction of the gas barrier laminated polyester film of this invention exists in the range of 1-10 ppm /% RH, respectively. When the humidity expansion coefficient (alpha) h of a gas barrier laminated polyester film exists in such range, high gas barrier property is obtained. The humidity expansion coefficient αh in the MD direction and the TD direction is preferably in the range of 1 to 5 ppm /% RH, respectively. When the humidity expansion coefficients αh in the MD direction and the TD direction are less than the lower limit, respectively, it is necessary to add a large amount of the blend component having low hygroscopicity to the polyesters constituting the base film, and the heat resistance dimensions of the polyester film by these components Stability and transparency may fall. On the other hand, when the humidity expansion coefficients αh in the MD direction and the TD direction exceed the upper limits, respectively, the base film is hygroscopically expanded and expanded in a high humidity atmosphere, and changes in humidity with various functional layers including a gas barrier layer laminated on a substrate. From the difference in the dimensional change, the functional layer may not fully exhibit the original function due to cracks in various functional layers, and thus high gas barrier properties may not be obtained.

In order to achieve the range of these humidity expansion coefficients (alpha) h, the layer structure containing a gas barrier layer on at least 1 coating layer of a polyester base film, or the planarization layer and gas on at least 1 coating layer of a polyester base film The thing which has a laminated constitution of any one of the laminated constitution in which the barrier layer was laminated | stacked, and improving adhesiveness with both a base film and a gas barrier layer through a coating film layer is mentioned. By adhering each layer closely, the defect which becomes a permeation path of water vapor | steam reduces. In addition, when any stress is applied, defects due to the occurrence of cracks in the interfacial peeling or the gas barrier layer are less likely to occur, resulting in a slower diffusion rate of water vapor and less absorption of the base film even in a high humidity atmosphere. The gas barrier laminated film which has the range of the humidity expansion coefficient (alpha) h of this invention can be obtained.

More specifically, the humidity expansion coefficient αh of the present invention is, i) a layer structure in which a coating film layer, a planarization layer, and a gas barrier layer are sequentially laminated on one side of a polyester base film as a layer structure, or a substrate made of polyester. A layer structure comprising at least a coating layer and a gas barrier layer on both sides of the film in this order, ii) enhancing the adhesion of the above-described layers, specifically, the base film and the gas barrier layer or the planarizing layer. It is achieved by using the specific coating film layer which has the effect of improving adhesiveness, and iii) both the base films are i)-iii) which are extended | stretched of MD direction and TD direction by the magnification of 2.9 times or more. Moreover, in the case of the laminated constitution in which a coating film layer, a planarization layer, and a gas barrier layer were laminated | stacked in order on the single side | surface of a polyester base film, it is preferable that the minimum of iv) base film thickness satisfy | fills the range previously described further.

In addition, as a means for achieving a humidity expansion coefficient αh of 5 ppm /% RH or less, the i) layer structure described above is a three-layer structure in which a coating film layer, a planarization layer, and a gas barrier layer are sequentially stacked on both surfaces of a polyester base film. It is preferable to have.

<Water vapor transmittance>

It is preferable that the water vapor transmission rate of the gas barrier laminated polyester film of this invention is 0.1 g / m <2> / day or less in 40 degreeC and the high humidity conditions of 90% RH. The water vapor transmission rate at 40 ° C. and 90% RH is more preferably 0.05 g / m 2 / day or less, and particularly preferably 0.01 g / m 2 / day or less. The lower limit of the water vapor transmission rate at 40 ° C. and 90% RH is not particularly limited, and is usually less than the detection limit of the MOCON method. The lower limit of the water vapor transmission rate in terms of conversion is preferably 10 × 10 ⁻⁶ g / m 2 / day or more.

 The above-mentioned range of water vapor transmission rate improves the adhesiveness with a planarization layer or a gas barrier layer using (A)-(C) component as a structural component of a coating film layer, and a layer structure is provided to one side of a polyester base film. This is achieved by a layer structure in which a coating film layer, a planarization layer, and a gas barrier layer are laminated in this order, or a layer structure including at least a coating film layer and a gas barrier layer in this order on both surfaces of a base film made of polyester. The gas barrier layer itself is a layer having a gas barrier function, but having a gas barrier layer alone causes some defects that can be a gas transmission path, and the level of gas barrier properties required for organic EL display and electronic paper applications, That is, gas barrier properties expressed by the water vapor transmission rate described above cannot be obtained. Therefore, the gas barrier property of the above-mentioned range is achieved by laminating | stacking the layer which consists of a metal oxide or a metal nitride on a base film via the coating film layer and planarization layer of this invention. In addition, when the base film is ethylene naphthalate, higher gas barrier properties are achieved.

<Production method>

The polyester film of this invention melt-extrudes polyester to a film form, it solidifies by cooling in a casting drum, and it is set as an unstretched film, and this unstretched film is lengthwise (Tg- (Tg + 60) degreeC of polyester resin. It is obtained by extending | stretching biaxially at 2.0-5.0 times magnification in MD) direction and a transverse (TD) direction, and heat-setting for 1 to 100 second at the temperature of (Tm-100)-(Tm-5) degreeC.

In order for the draw ratio of MD direction and TD direction to have the Young's modulus and humidity expansion coefficient (alpha) h of this invention, it is preferable that a minimum is 2.9 times or more. Moreover, it is preferable that an upper limit is 3.9 times or less for the draw ratio of MD direction and a TD direction to provide the Young's modulus of this invention and the heat shrink rate in 200 degreeC.

Stretching can be performed by a method generally used, for example, by a roll method or a method using a stenter, and may be simultaneously drawn in the MD direction and the TD direction, or may be sequentially drawn in the MD direction and the TD direction. . When the coating film layer is gradually drawn, it can be formed by apply | coating an aqueous coating liquid to the uniaxial oriented film extended | stretched to one direction, extending | stretching and heat-setting in the other direction in that state. As a coating method of a coating film layer, the well-known arbitrary coating methods can be applied. For example, a roll coating method, a gravure coating method, a roll brush method, a spray coating method, an air knife coating method, an impregnation method, a curtain coating method, etc. can be used individually or in combination. The coating amount is preferably 0.5 to 20 g, more preferably 1 to 10 g, per 1 m 2 of running film. The aqueous solution is preferably used as an aqueous dispersion or emulsion.

Moreover, when performing a relaxation process, it is effective to perform heat processing at the temperature of (X-80)-X degreeC of a film. X represents here being a heat setting temperature. In the relaxation treatment method, between the heat setting and the roll, the process is performed. I) A method of separating both ends of the film in the middle of the heat setting zone and reducing the take-up speed with respect to the feeding speed of the film. ii) a method of heating with an IR heater between two conveying rolls having different speeds, iii) a method of conveying a film on a heated conveying roll to reduce the speed of the conveying roll after the heating conveying roll, iv) hot air after heat setting The method of slowing down a take-up speed rather than a feed speed is conveyed, conveying a film on the nozzle which blows out. Moreover, after winding up the film forming machine, the method of slowing down the roll speed of the winding side rather than the roll speed of the film supply side, heating a film, and performing a relaxation process are also mentioned. As a heating means in this case, the method of heating a roll, the method of using a heating oven, an IR heater, etc. are mentioned.

What kind of method may be used for a relaxation process, and it is preferable to perform a relaxation process by making the deceleration rate of the speed | rate of a take-out side into 0.1 to 10% with respect to the speed of a supply side.

In order to obtain the polyester film which has the heat shrinkage characteristic in 200 degreeC of this invention, it extends | stretches to MD direction and TD direction at the draw ratio of 3.9 times or less, respectively, and (Tm-100)-(Tm-5) degreeC It is achieved by performing heat setting for 1 to 100 seconds at a temperature, and then performing a relaxation treatment at a temperature of (X-80) to X ° C.

A planarization layer is formed by apply | coating a planarization composition solution on the coating film layer of the obtained polyester film, and heat-processing in the temperature range of 100-150 degreeC. Further, a gas barrier layer is formed on the coating layer or the planarization layer by using a sputtering method or the like.

<Use>

The polyester film for gas barrier processing of this invention is used suitably as a board | substrate film of image display apparatuses, such as the use for which gas barrier property and transparency are strongly requested | required, for example, organic electroluminescent display, an electronic paper. Moreover, it can also be used as substrate films, such as a liquid crystal display and an organic TFT.

Moreover, since the gas barrier laminated polyester film of this invention is excellent in gas barrier property and transparency, it is used suitably as an image display apparatus which requires these characteristics, for example, an organic electroluminescent display board | substrate and an electronic paper substrate. It can also be used as a liquid crystal display substrate and an organic TFT substrate.

Example

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated based on an Example. Each characteristic value and the evaluation method were measured and evaluated by the following method. In addition, a film sample refers to the film which consists of a coating film layer, when a polyester base film and a coating film layer are formed.

(1) film thickness

The film sample thickness was measured by the immersion pressure 30g using the electronic micrometer (brand name "K-312A type" by Anritsu Corporation).

(2) haze, total light transmittance

According to JIS standard K7105, the total light transmittance Tt (%) and scattered light transmittance Td (%) of a film sample are calculated | required, and haze ((Td / Tt) * 100) (%) is computed.

Hayes

A: 1.5% or less

B: more than 1.5%

Total light transmittance

A: 85% or more

B: less than 85%

(3) heat shrinkage

The film sample was drawn at 30 cm intervals, heat treated in an oven at a predetermined temperature without applying a load, and the gap between the marks after the heat treatment was measured, and the heat shrinkage was calculated in the following directions in the MD and TD directions, respectively. . Heat shrinkage percentage (%) = ((distance between gage marks before heat treatment-distance between gage marks after heat treatment) / distance between gage marks before heat treatment) × 100

The following reference | standard evaluated the thermal contraction rate after heat-processing 150 degreeC * 30 minutes.

A: 150 ° C heat shrinkage of MD and TD≤0.05%

B: 0.05% <MD, 150 DEG C heat shrinkage of TD≤0.1%

C: 0.1% <MD, 150 ° C heat shrinkage of each TD

The following reference | standard evaluated the heat shrink rate after 200 degreeC * 10 minute heat processing.

A: 200 ° C heat shrinkage of MD and TD≤0.2%

B: 0.2% <MD, 200 ° C. heat shrinkage of each TD

(4) thickness of coating layer

A small piece of film was embedded in an epoxy resin (trade name "Epomount" manufactured by Refinefine Inc.) and sliced into 50 nm thickness for each embedding resin using a Microtome2050 manufactured by Reichert-Jung Co., Ltd., and a transmission electron microscope ( LEM-2000), it observed with acceleration voltage 100KV and magnification 100,000 times, and measured the thickness of the coating film layer.

(5) Average particle diameter of particles in coating layer

The same operation as the measurement of the coating film layer thickness was performed, and the particle diameter of 100 particles was measured, and the average value was made into the average particle diameter.

(6) shear resistance of coating layer

Using a film sample cut to a width of 20 mm, the film layer surface of the film was run for 80 m with a load of 200 g in accordance with a fixed column made of a columnar stainless steel with a diameter of 10 mm. Evaluate as follows.

A: No sticking of powder on the bar · · · · Good cutting resistance

B: small amount of powder adheres to the bar

(7) blocking property

After using two film samples cut | disconnected in 50 mm width, the coating film surface and the surface on which the coating film layer is not apply | coated were piled up, and after processing for 17 hours at 60 degreeC x 80% RH under a load of 50 kg / cm <2>, The peeling force of a layer surface and a non-coating layer surface is measured, and blocking resistance is evaluated as follows.

A: Peeling force ≤ 10 g Good blocking resistance

B: 10 g <peeling force ≤ 30 g

C: 30 g <Peeling force · Bad blocking resistance

(8) Adhesion between the planarization layer and the base material layer

100 parts of ethylene-vinyl alcohol copolymers (manufactured by Kuraray Co., Ltd., product name "Eval", hereinafter sometimes referred to as EVOH) are dissolved by heating in a mixed solvent of 720 parts of water and 1080 parts of n-propanol, and the leveling agent in this solution. After 0.1 part and 39 parts of acetic acid were added (Toray Dow Corning Co., Ltd. product name "SH30PA"), 211 parts of 2- (3, 4- epoxycyclohexyl) ethyltrimethoxysilane were added and it stirred for 10 minutes. Furthermore, 77 parts of 3-aminopropyltrimethoxysilane were added to this solution, and it stirred for 3 hours, and obtained the coating composition. This coating composition was coated on the coating layer surface of the polyester film, and 130 degreeC * 3 heat | fever treatment was performed, and the planarization layer of 2 micrometers in thickness was formed.

A cross cut (100 square meters of 1 m 2) in the shape of a checkerboard eye was formed on the planarization layer surface, and a cellophane tape (manufactured by Nichiban Co., Ltd.) having a width of 24 mm was attached thereon, and rapidly peeled off at a peeling angle of 180 degrees. The peeling surface was observed and evaluated based on the following criteria. In addition, in this evaluation method, since the planarization layer and the coating film layer are cut | disconnected, it peels at the interface with weaker adhesive force between a base material-coating layer and between coating-film layer-flattening layer. Therefore, after peeling test, presence of the microparticles | fine-particles contained in a coating film layer was confirmed with the optical microscope, and it was judged which interface is peeling off.

A: Peeling area is less than 10% Very good adhesion

B: Peeling area is 10% or more but less than 40%.

C: Peeling area exceeds 40%.

(9) humidity expansion coefficient αh

A film sample piece was cut out to 15 mm in length and 5 mm in width, and it was set in TMA3000 made by Shin-Kyu-poong, and it kept constant at 30 degreeC and nitrogen atmosphere at 30% RH * 16hr, and humidity 70% RH * 16hr. And the sample length in each humidity condition is measured, and a humidity expansion coefficient is computed by following formula (3). In addition, the humidity expansion coefficient of MD direction made the longitudinal direction of a film the measurement direction, and the humidity expansion coefficient of the TD direction made the horizontal direction of a film the measurement direction. Ten film samples were measured about each direction, and the average value was made into (alpha) h.

αh = {(L ₂ -L ₁ ) / (L ₁ × ΔH)} (3)

Here, in the above formula, L ₁ is the sample piece length (mm) at 30% RH humidity, L ₂ is the sample piece length (mm) at 70% RH humidity, and ΔH is 40 (= 70-30)% RH. Respectively.

In addition, Examples 1-31 and Comparative Examples 2-8 of Table 1, 2 show a coating film layer, a planarizing layer, and the single side | surface of a polyester base film according to the evaluation method of (8) adhesiveness and (10) gas barrier property. (Alpha) h was measured using the laminated | multilayer film which laminated | stacked the gas barrier layer. Examples 32-35 and Comparative Examples 9 and 10 of Table 3 measured αh using the film of a laminated constitution in Table 3, respectively.

A: 1ppm /% RH≤αh <5ppm /% RH Very good dimension stability

B: 5ppm /% RH≤αh≤10ppm /% RH

C: 10ppm /% RH <αh≤15ppm /% RH

D: 15ppm /% RH <αh Very poor dimension stability

(10) Gas barrier property (water vapor barrier property (evaluation method 1))

(8) A SiO ₂ film having a thickness of 30 nm was formed on the planarization layer formed on the coating layer in accordance with the evaluation method of adhesion, by using a Permran W1A manufactured by MOCON under 40 ° C and 90 RH% atmosphere. The water vapor transmission rate in was measured and gas barrier properties were evaluated based on the following criteria.

A: water vapor transmission rate ≤0.05 g / m 2 / day Very good barrier

B: 0.05 g / m 2 / day <water vapor transmission rate ≤0.1 g / m 2 / day

C: 0.1g / ㎡ / day <Water vapor transmittance · · · · · Barrier poor

(11) gas barrier property (water vapor barrier property (evaluation method 2))

Using the film sample of the laminated constitution described in each Example and the comparative example, the water vapor transmission rate in 40 degreeC and 90 RH% atmosphere is measured using the Permtran W1A by M0CON Co., Ltd. Evaluated.

A: Water vapor transmission rate ≤ 0.05g / m2 / day Very good barrier

B: 0.05 g / m 2 / day <water vapor transmission rate ≤0.1 g / m 2 / day

C: 0.1g / ㎡ / day <Water vapor transmittance · · · · · Barrier poor

(12) Water vapor barrier property after high temperature thermal history

Water treatment was performed at 200 ° C. for 10 minutes using a film having the same laminated constitution as (10) or (11), and thereafter, water vapor of the film was used at 40 ° C. and 90 RH% atmosphere using Permran W1A manufactured by MOCON. The transmittance was measured and evaluated based on the following criteria.

A: Water vapor transmission rate ≤ 0.05g / m2 / day Very good barrier

B: 0.05 g / m 2 / day <water vapor transmission rate ≤0.1 g / m 2 / day

C: 0.1g / ㎡ / day <Water vapor transmittance · · · · · Barrier barrier property

Example 1

100 parts of dimethyl naphthalene-2,6-dicarboxylic acid and 60 parts of ethylene glycol were transesterified for 120 minutes, using 0.03 part of manganese acetate tetrahydrate as a transesterification catalyst, gradually heating up from 150 degreeC to 238 degreeC. When the reaction temperature reached 170 degreeC, trimethyl phosphate (The solution heat-processed by pressure of 135 degreeC in ethylene glycol at 0.11-0.16 MPa for 5 hours: 0.023 part in trimethyl phosphate equivalent) was added, and transesterification reaction was complete | finished. Thereafter, 0.024 parts of antimony trioxide was added.

The reaction product is then transferred to a polymerization reactor, heated up to 290 ° C, subjected to a polycondensation reaction under a high vacuum of 27 Pa or less, and substantially free of particles having an intrinsic viscosity of 0.61 dl / g, polyethylene-2,6 -Naphthalenedicarboxylate was obtained.

After drying the pellet of this polyethylene-2,6-naphthalenedicarboxylate at 170 degreeC for 6 hours, it supplies to an extruder hopper, melts at melting temperature of 305 degreeC, and passes through a 2 mm slit-shaped die, and has a surface temperature of 60 degreeC. Extruded on a rotary cooling drum and quenched to obtain an unstretched film. The obtained unstretched film was preheated at 120 degreeC, and also it extended | stretched 3.1 times in the longitudinal direction by heating with a 900 degreeC IR heater 15 mm above between low speed and high speed rolls. In order to form a coating film layer on the single side | surface of this longitudinal stretched film, the aqueous liquid of 4 weight% of solid content concentration which consists of the following compositions is apply | coated with a roll coater, it is supplied to a tenter, and it is 3.5 in the horizontal direction at 145 degreeC. Stretched by ship.

After heat-setting the obtained biaxially-oriented film for 40 second at the temperature of 240 degreeC, and winding up the 100-micrometer-thick polyester film, a relaxation process was performed at 200 degreeC of treatment temperature and 1.0% of relaxation rate using the heating zone by IR heater. It carried out and obtained the stretched film (film sample). The characteristic of the obtained film sample is shown to Table 1, 2, 3.

Adhesive evaluation evaluated by laminating | stacking the planarization layer on the coating film layer of a film sample in accordance with the method as described in (8) Adhesive evaluation. In addition, evaluation of gas barrier property and a humidity expansion coefficient is performed using the film of the structure by which the coating film layer, the planarizing layer, and the gas barrier layer were sequentially laminated on one side of the base film according to the method described in (10) Gas barrier property evaluation. It was.

Excellent adhesion to both the planarization layer and the base film was obtained, and the coating film layer was excellent in durability, and the laminated film obtained by barrier processing had excellent gas barrier properties.

<Coat layer component>

(A) Copolyester resin: Copolymer polyester consisting of 60 mol% of terephthalic acid, 36 mol% of isophthalic acid and 4 mol% of 5-Nasulfoisophthalic acid, 60 mol% of ethylene glycol and 40 mol% of neopentiglycol (Tg) = 30 ° C, hereinafter abbreviated as E.) 55 wt%

(B) Polyvinyl alcohol: Polyvinyl alcohol having a saponification degree of 74-80% (hereinafter abbreviated as J) 16% by weight

(C) Microparticles | fine-particles: 10 weight% of spherical silica particles (henceforth abbreviated as N.) with an average particle diameter of 80 nm.

(D) Crosslinking agent: 10 weight% of N, N, N ', N'- tetraglycidyl meta xylylenediamine (it abbreviates as R hereafter) of an epoxy resin.

(E) Wetting agent: 9% by weight of polyoxyethylene lauryl ether

Comparative Example 1

It carried out similarly to Example 1 except not applying the aqueous liquid which forms a coating film layer. Table 1 shows the properties of the obtained film.

The planarization layer and the gas barrier layer were respectively laminated on one side in the same manner as in Example 1, and a flattening layer was directly formed on one side of the polyester substrate film.

[Examples 2-20, Comparative Examples 2-7]

It implemented like Example 1 except changing the kind and ratio of (A)-(D) component which comprise a coating film layer as shown in Table 1. Table 1 shows the properties of the obtained film. As is clear from the results shown in Table 1, each example has excellent adhesion to both the planarization layer and the base film, the coating layer is excellent in durability, and the laminated film obtained by barrier working has excellent gas barrier properties. Had.

In addition, in Table 1, the following copolyesters were used for the types F-I of (A) copolyester resin, respectively.

F: <acid component> 20 mol% of 2, 6- naphthalenedicarboxylic acid, 76 mol% of isophthalic acids, 4 mol% of 5-K sulfoterephthalic acids / <diol component> 50 mol% of ethylene glycol, 50 mol% of neopentiglycol ( Tg = 42 ℃)

G: <acid component> 70 mol% of terephthalic acids, 24 mol% of isophthalic acids, 6 mol% of 5-Na sulfoterephthalic acids / <diol component> 60 mol% of ethylene glycol, 3 mol% of diethylene glycol, 37 mol% of neopentiglycol (Tg = 65 ℃)

H: <acid component> 16 mol% of terephthalic acid, 80 mol% of isophthalic acids, 4 mol% of 5-Na sulfoterephthalic acid / <diol component> 5 mol% of diethylene glycol, 60 mol% of 1, 4- butanediol, and 35 mol% of neopentiglycol (Tg = 17 ° C)

I: <acid component> 77 mol% of 2, 6- naphthalenedicarboxylic acid, 19 mol% of terephthalic acids, 4 mol% of 5-K sulfoterephthalic acid / <diol component> 90 mol% of ethylene glycol, 10 mol% of neopentiglycol (Tg = 98 ℃)

In addition, the following compounds were used for the types K-M of (B) polyvinyl alcohol, respectively.

K: polyvinyl alcohol having a saponification degree of 85-90 mol%

L: Polyvinyl alcohol having a saponification degree of 91-95 mol%

M: polyvinyl alcohol of saponification degree 65-72mol%

The following compounds were used for the types O-Q of (C) microparticles | fine-particles, respectively.

O: spherical silica particles having an average particle diameter of 60 nm

P: spherical silica particles with an average particle diameter of 120 nm

Q: colloidal silica particles with an average particle diameter of 10 nm

(D) Kinds of crosslinking agents S to U used the following compounds, respectively.

S: melamine resin trimethoxymethylmelamine (etherylated trimethylolmelamine with methanol)

T: Copolymer having an oxazoline group Copolymer of 60 mol% of 2-propenyl-oxazoline and 40 mol% of methyl methacrylate

U: Dimethylol Ethylene Urea

Example 21

A film was obtained in the same manner as in Example 1 except that the relaxation treatment at 200 ° C. was not performed. The characteristic of the obtained film is shown in Table 2. Although the part which lacks high temperature dimensional stability, the film also has high gas barrier property and was excellent in transparency.

[Examples 22 to 24]

A film was obtained in the same manner as in Example 1 except that the thickness of the film was different. The characteristic of the obtained film is shown in Table 2. The obtained film was also excellent in transparency, dimensional stability, and the gas barrier property of the base material.

[Example 25]

A film was obtained in the same manner as in Example 1 except that the draw ratio was different. The characteristic of the obtained film is shown in Table 2. The obtained film was also excellent in transparency, dimensional stability, and the gas barrier property of the base material.

Example 26

A film was obtained in the same manner as in Example 1 except that the draw ratio was different. The characteristic of the obtained film is shown in Table 2. Although the obtained film had a part lacking high temperature dimensional stability, it was also excellent in transparency and gas barrier property of a base material.

[Example 27]

96 parts of dimethyl terephthalate, 58 parts of ethylene glycol, and 0.038 parts of manganese acetate were injected into the reactor, and the transesterification reaction was carried out while distilling methanol until the internal temperature became 240 ° C under stirring. 0.097 part of trimethyl phosphate was added and 0.041 part of antimony trioxide was added after the transesterification reaction was complete | finished. Subsequently, the reaction product was heated up and finally condensed under conditions of high vacuum at 280 ° C to obtain chips of polyethylene terephthalate having an intrinsic viscosity ([η]) of 0.64.

Next, after drying the chip of this polyethylene terephthalate at 170 degreeC for 3 hours, it supplied to the twin screw extruder, melt-kneaded at 280 degreeC, and solidified rapidly and obtained the master chip.

After pelleting this polyethylene terephthalate at 160 degreeC for 3 hours, it supplied to the extruder hopper, melted at 295 degreeC of melting temperature, and rapidly solidified on the cooling drum hold | maintained at 20 degreeC, and obtained the unstretched film. The unstretched film was stretched 3.1 times in the longitudinal direction at 95 ° C., and then coated on the single side with the same coating agent as in Example 1 so that the thickness after drying was 0.1 μm, and stretched at 110 times in the transverse direction at 3.5 times, then 230 It heat-processed at ° C and obtained the biaxially stretched film whose thickness is 100 micrometers. The characteristic of the obtained film is shown in Table 2. Although high temperature dimensional stability is not enough, the film which is also excellent in transparency and gas barrier property of a base material was obtained.

[Example 28]

Using the heating zone by an IR heater, a film was obtained in the same manner as in Example 27 except that the relaxation treatment was performed at a treatment temperature of 160 ° C. and a relaxation rate of 1.0%. The characteristic of the obtained film is shown in Table 2. Although the dimensional stability in 200 degreeC was not enough, the film in which the dimensional stability in 150 degreeC was favorable and also the transparency and gas barrier property of a base material were obtained was obtained.

[Example 29]

A film was obtained in the same manner as in Example 27 except that the thickness of the film was different. The characteristic of the obtained film is shown in Table 2. Although the high temperature dimensional stability and the barrier property of the base material were insufficient, the film excellent in transparency was obtained.

[Comparative Example 8]

A film was obtained in the same manner as in Example 21 except that 0.1% by weight of spherical silica particles having an average particle diameter of 0.35 µm was mixed with polyethylene-2,6-naphthalenedicarboxylate. The characteristic of the obtained film is shown in Table 2. Since it contained inert particle as a lubricant, it was a film lacking optical characteristics.

[Example 30]

A laminated film was obtained in the same manner as in Example 1 except that the coating film layer, the planarization layer, and the gas barrier layer were formed on both surfaces of the polyester film. The characteristic of the obtained laminated | multilayer film is shown in Table 3.

[Example 31]

Except not having provided the planarization layer in both surfaces, operation similar to Example 30 was performed and the laminated film was obtained. The characteristic of the obtained laminated | multilayer film is shown in Table 3.

[Example 32]

Except not having formed a planarization layer, the operation similar to Example 1 was performed and the laminated film was obtained. The characteristic of the obtained laminated | multilayer film is shown in Table 3.

[Example 33]

A laminated film was obtained in the same manner as in Example 1 except that the draw ratio was different. The characteristic of the obtained laminated | multilayer film is shown in Table 3.

[Comparative Example 9]

A laminated film was obtained in the same manner as in Example 33 except that the coating film layer and the planarization layer were not formed. The characteristic of the obtained laminated | multilayer film is shown in Table 3.

Industrial availability

Since the polyester film for gas barrier processing of this invention has a high gas barrier property, and also has high transparency and diactivation, when a gas barrier layer is further formed, the organic electroluminescent display which has these characteristics and an electron It can use suitably for substrate films, such as paper. Moreover, since the gas barrier laminated polyester film of this invention has a high gas barrier property and also has high transparency and diactivity, it can use suitably as an organic electroluminescent display board | substrate and an electronic paper board | substrate which require these characteristics. have.

Claims (29)

A polyester film for gas barrier processing, wherein a coating film layer is formed on at least one side of a base film made of polyester, and the coating layer is 50 to 80% by weight of (A) copolyester resin based on the weight of the coating film layer (B). Polyvinyl alcohol containing 10 to 30% by weight and (C) fine particles 3 to 25% by weight, and the total light transmittance of the polyester film is 85% or more, haze is 1.5% or less, characterized in that the poly for gas barrier processing Ester film. The method of claim 1, (A) Polyester film for gas barrier processing whose glass transition point of copolyester resin is 20-90 degreeC. The method of claim 1, (B) The polyester film for gas barrier processing whose saponification degree of polyvinyl alcohol is 74-90 mol%. The method of claim 1, (C) Polyester film for gas barrier processes whose average particle diameter of microparticles | fine-particles is 20-100 nm. The method of claim 1, The polyester film for gas barrier processes in which a coating film layer contains 1-20 weight% of (D) crosslinking agents. 6. The method of claim 5, (D) The polyester film for gas barrier processing whose crosslinking agent is at least 1 sort (s) chosen from the group which consists of an oxazoline group containing polymer, urea resin, melamine resin, and epoxy resin. The method of claim 1, The polyester film for gas barrier processes whose thermal contraction rate in 150 degreeC * 30 minutes is 0.1% or less of MD direction and TD direction, respectively. The method of claim 7, wherein The polyester film for gas barrier processes whose heat shrinkage in 200 degreeC * 10 minutes is 0.2% or less of MD direction and TD direction, respectively. The method of claim 1, Polyester film for gas barrier processing whose polyester of base material is polyethylene naphthalate. The method of claim 9, The polyester film for gas barrier processing whose polyethylene naphthalate is 90 mol% or more of ethylene-2,6-naphthalenedicarboxylate based on the number-of-moles of all the repeating structural units. The method of claim 1, Polyester film for gas barrier processing used as a substrate film of organic electroluminescent display or electronic paper. A gas barrier laminated polyester film in which a gas barrier layer is further laminated on at least one coating film layer of the polyester film for gas barrier processing according to claim 1. 13. The method of claim 12, The gas barrier laminated polyester film whose gas barrier layer is a metal oxide or a metal nitride. The method of claim 13, A gas barrier laminated polyester film, wherein the gas barrier layer comprises SiO _x (1.5 ≦ _x ≦ 2.0). The method of claim 13, The gas barrier laminated polyester film whose humidity expansion coefficient (alpha) h of MD direction and TD direction is 1-10 ppm /% RH, respectively. The method of claim 13, The gas barrier laminated polyester film whose water vapor transmission rate in 40 degreeC and 90% RH is 0.1 g / m <2> / day or less. An organic EL display substrate comprising the gas barrier laminate polyester film according to any one of claims 12 to 16. The electronic paper substrate containing the gas barrier laminated polyester film in any one of Claims 12-16. A laminated polyester film for gas barrier processing, wherein a planarization layer is further laminated on at least one coating film layer of the polyester film for gas barrier processing according to claim 1. 20. The method of claim 19, The laminated polyester film for gas barrier processes in which a planarization layer contains polyvinyl alcohol. 20. The method of claim 19, Epoxy silicon-based compound selected from the group consisting of (a) a silicon compound having an epoxy group and an alkoxysilyl group, its (partial) hydrolyzate, its (partial) condensate, and mixtures thereof, (b) amino group and alkoxy Crosslinking reaction of the silicon compound having a silyl group, the (partial) hydrolyzate, the (partial) condensate, and an aminosilicon compound selected from the group consisting of these mixtures, and (c) a polyvinyl alcohol or a polyvinyl alcohol copolymer The laminated polyester film for gas barrier processing which is a hardened polymer layer formed by making. 20. The method of claim 19, The laminated polyester film for gas barrier processes whose peeling area of the planarization layer measured by a cross cut test method is 10% or less. A gas barrier laminated polyester film in which a gas barrier layer is further laminated on at least one planarization layer of the laminated polyester film for gas barrier processing according to claim 19. 24. The method of claim 23, The gas barrier laminated polyester film whose gas barrier layer is a metal oxide or a metal nitride. 25. The method of claim 24, A gas barrier laminated polyester film, wherein the gas barrier layer comprises SiO _x (1.5 ≦ _x ≦ 2.0). 25. The method of claim 24, The gas barrier laminated polyester film whose humidity expansion coefficient (alpha) h of MD direction and TD direction is 1-10 ppm /% RH, respectively. 25. The method of claim 24, The gas barrier laminated polyester film whose water vapor transmission rate in 40 degreeC and 90% RH is 0.1 g / m <2> / day or less. An organic EL display substrate comprising the gas barrier laminate polyester film according to any one of claims 23 to 27. An electronic paper substrate comprising the gas barrier laminated polyester film according to any one of claims 23 to 27.