JP3064328B2 - Coated polyester film and vapor deposited film using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a coated polyester film having an excellent adhesion to a vapor deposition layer to be formed on its surface even in the presence of hot water. It relates to the deposited film used.

(Prior art) Polyester films on which metals and metal oxides are deposited, especially metal-deposited polyethylene terephthalate films, are excellent in gas barrier properties, water impermeability, visible / ultraviolet light shielding properties, heat ray reflection properties, etc. It is used for applications. For example, it is used as a packaging material for food and industrial parts, a decoration material, a window glass shielding material, a gold / silver thread material, various protective coating materials, and the like. However, the adhesiveness (adhesion) between the substrate layer and the vapor-deposited layer of the vapor-deposited film, particularly when water is present, is not always sufficient. For example, when food is packaged with a heat-sealing film in which a heat-sealing layer made of a polyolefin resin is laminated on the film surface of a metal-deposited polyester-based base film, when a boiling treatment is performed for the purpose of sterilization, a vapor-deposited layer is formed. Has the disadvantage that it is easily peeled off.

As a method for improving the adhesion between the polyester base film and the metal deposition layer, for example, JP-B-55-232 and JP-A-56-16549, in addition to polyester, other copolymer composition For preparing a base film by mixing the same. Further, JP-A-57-87357 discloses a method of physically changing the surface state of a base film, and JP-B-59-51424 discloses a resin composition specific to the base film surface. A method of forming a layer of the resin composition by applying a solution is disclosed. However, even if these methods are adopted, the adhesiveness between the base film or the laminated film and the metal deposition layer is still not sufficient, and the adhesiveness is not sufficient in the presence of water, especially hot water. Is enough. In addition, of the above methods,
In the method for applying a resin composition solution described in Japanese Patent No. 51424, flammability and toxicity are concerned because an organic solvent is used, and there is a danger in work. It is not preferable in terms of pollution generation and energy saving.

As a method of enhancing the adhesiveness of a base film and a coating layer formed on the surface thereof in the presence of water, for example,
JP-B-55-45835 and JP-B-55-12870 disclose methods for improving the adhesion between a substrate film and a printed layer. According to this method, a polyester having a specific composition is blended in the base film. However, this method has a relatively good effect when the layer to be laminated on the base film is a printed layer. However, when the layer to be laminated is a metal-deposited layer, it can be used in the presence of water. In particular, the adhesiveness in the presence of hot water is still not sufficient.

JP-A-48-37480 discloses specific polyester-based resin and polyether-based resin compositions, for example, as an undercoating agent for improving the adhesion between a polyester substrate and a layer laminated thereon. These resin compositions have good adhesiveness to polyester as a base material, but often have insufficient adhesiveness to a metal deposition layer to be laminated. Further, when the above resin composition is applied to a substrate, an organic solvent is used.
As in the case of JP 59-51424, there is a work hazard due to flammability and toxicity.

As a method of forming an undercoat layer on a base film without using an organic solvent, Japanese Patent Publication No. 54-16557 discloses a method of applying an aqueous solution containing a composition in which components are changed to water-soluble. Have been. However, the disadvantage is that, for example, the resulting vapor-deposited film has poor water resistance because the composition used is essentially water-soluble. Also in the production process, there is a disadvantage that the aqueous solvent has poor wettability with respect to the hydrophobic substrate film, and it is difficult to obtain a uniform coating film.

As described above, the adhesiveness with an inorganic vapor-deposited layer such as a metal, particularly the adhesiveness in the presence of hot water is good. At present, the used vapor deposition film has not been obtained.

(Problems to be Solved by the Invention) The present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide excellent interlayer adhesion with an inorganic vapor deposition layer, particularly excellent adhesion in the presence of hot water. Another object of the present invention is to provide a polyester film excellent in boil resistance and a vapor-deposited film using the same.

(Means for Solving the Problems) The present invention provides a coated polyester film, wherein a resin coating layer is formed on at least one surface of a base film made of a polyester resin, wherein the resin coating layer is formed of an ester. A resin composition mainly containing a water-insoluble thermoplastic resin containing at least one segment having a bond in a molecule, and a tensile elongation ε at 60 ° C. of a film made of the resin composition.
(%) Is 100 ≦ ε ≦ 500, thereby achieving the above object.

The vapor-deposited polyester film of the present invention is obtained by providing an inorganic vapor-deposited layer on the surface of the resin coating layer of the above-mentioned coated polyester film.

As the base film used for the coated polyester film of the present invention, a film of a thermoplastic polyester resin, for example, a film of polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, or the like is suitable. In particular, a copolymerized polyester film in which 80% or more of the components correspond to polyethylene terephthalate (that is, the terephthalic acid component and the ethylene glycol component are 80% or more of all components), or a polyester containing polyethylene terephthalate in a ratio of 80% or more Blend films are preferably used. The polyester component other than the polyethylene terephthalate component of such a copolyester film or polyester blend film may be any polyester component. As the dicarboxylic acid component constituting such a polyester, any of aromatic, aliphatic and alicyclic dicarboxylic acids can be used. As aromatic dicarboxylic acids, isophthalic acid, orthophthalic acid, 2,6-
Naphthalenedicarboxylic acids and the like, aliphatic dicarboxylic acids include succinic acid, adipic acid, sebacic acid, oxalic acid and the like, and alicyclic dicarboxylic acids include 1,3-
Examples include cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. As the aromatic dicarboxylic acid,
Some of the oxyacids such as p-hydroxybenzoic acid are preferably used. As the glycol component constituting the polyester, an aliphatic glycol having 2 to 8 carbon atoms or an alicyclic glycol having 6 to 12 carbon atoms is preferable. Such glycols include ethylene glycol, 1,2
-Propanediol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, 1,2-cyclohexanedimethanol, 1,3-
Cyclohexane dimethanol, 1,4-cyclohexane dimethanol, p-xylene glycol, diethylene glycol, triethylene glycol, and the like. In addition,
It is also possible to use polyether glycols as aliphatic glycols, such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol and the like.

These acid components and dicarboxylic acid components are polymerized (or copolymerized) by an ordinary method to prepare a polyester. The polyester is appropriately mixed as needed, and is usually formed into a film (base film) by melt-extrusion or by dissolving in a solvent and casting. The base film to be used is uniaxially or biaxially stretched as necessary.

The resin composition used in the resin coating layer on the surface of the base film is a main component of a water-insoluble thermoplastic resin containing at least one segment having an ester bond in a molecule. And the tensile elongation ε (%) at 60 ° C. of the film made of this resin composition is 100 ≦ ε ≦ 500. The tensile elongation of the resin composition, in the tensile test,
It is expressed by the elongation (%) of the test piece immediately before the film-like test piece made of the resin composition breaks. The tensile elongation of the coating layer resin composition measured in this way affects the interlayer adhesion between the deposited layer and the coated layer of the prepared deposited film. It is considered preferable to use the tensile elongation at a temperature (90 to 100 ° C) corresponding to hot water as a measure of the interlayer adhesive force at the time of hot water treatment. No, the measured value at 60 ° C. shows a good correlation with the adhesiveness during hot water treatment.
The tensile elongation at ° C. was used. If ε is less than 100%, when the film is boiled in hot water, the strain and stress applied to the film cannot be sufficiently reduced by the coating layer, and the base material and the deposition layer are separated. Easy and inferior in boil resistance. If ε exceeds 500%, the coating layer is likely to be blocked and handling of the coating film becomes difficult. ε
Preferably satisfies 100 ≦ ε ≦ 300.

The thermoplastic resin forming such a resin coating layer is not particularly limited as long as the above properties are satisfied. A polyester-based copolymer, an acrylic-based polymer, a polyester-type polyurethane-based polymer, and a mixture thereof are preferably used. Particularly preferably, a polyester-type polyurethane polymer and a derivative thereof are used. When these thermoplastic resins do not contain a segment having an ester bond in the polymer molecule, the adhesion between the coating layer and the base polyester film becomes insufficient, which is not preferable. For example, when a polyether-type polyurethane polymer or a polyamide-based polymer is used, the adhesion between the substrate film and the coating layer is low, so that the coating layer is easily peeled from the substrate film.

Polyurethane-based copolymers are ester condensation polymers obtained from one or more dicarboxylic acid components and one or more polyhydric alcohols. In particular, copolymers which are insoluble in water; and which are dispersible in water or organic solvents or soluble in organic solvents are preferably used. Further, the glass transition temperature of the copolymer is preferably from 20 to 80 ° C. As the dicarboxylic acid component, terephthalic acid, isophthalic acid, orthophthalic acid, aromatic dicarboxylic acids such as naphthalenedicarboxylic acid, and alkyl esters thereof,
Or derivatives having a substituent such as sulfonate, phosphate, carboxylate or the like introduced therein; aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, succinic acid, oxalic acid, and derivatives thereof; and cyclohexanedicarboxylic acid And aliphatic dicarboxylic acids such as cyclopentanedicarboxylic acid, and derivatives thereof. As the polyhydric alcohol component, aliphatic glycols having 2 or more carbon atoms, alicyclic glycols, bisphenol compounds, and the like are used.

As the acrylic polymer, a polymer containing an ester of α, β unsaturated carboxylic acid such as acrylic acid or methacrylic acid as a monomer component in an amount of 50 mol% or more is used.
Such α, β unsaturated carboxylic acid esters include:
Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, amyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, etc. Alkyl esters; esters with aromatic alcohols such as phenyl (meth) acrylate; and esters with alicyclic alcohols such as cyclohexyl (meth) acrylate. In such an acrylic polymer, a monomer other than the above may be contained as a copolymer component within a range of less than 50 mol%. Examples of such a monomer include a styrene monomer and a vinyl monomer having a functional group such as a hydroxyl group, a carboxyl group, a glycidyl group, an amino group, an amide group, and a sulfone group.

The polyester-type polyurethane-based polymer is prepared from a polyester polyol, a diisocyanate, and, if necessary, a low-molecular compound having two or more active hydrogens.

The polyester polyol is obtained by reacting a dicarboxylic acid with a glycol. As the dicarboxylic acid, any of aromatic, aliphatic and alicyclic dicarboxylic acids can be used. As the aliphatic dicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, oxalic acid and the like are used. Among the non-aliphatic dicarboxylic acids, examples of the aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, orthophthalic acid, and 2,6-naphthalenedicarboxylic acid. Some of the oxy acids, such as p-hydroxybenzoic acid, may also be used. As the alicyclic dicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,2-
Examples thereof include cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid.

As the glycol component forming the polyester polyol, any of aliphatic glycols and alicyclic glycols having 2 or more carbon atoms can be used. It is preferable to use an alkylene glycol having 4 or more carbon atoms (eg, butanediol, hexanediol) in combination with an alicyclic glycol (eg, cyclohexanedimethanol) or a bisphenol compound.

A polyester polyol is usually prepared by a melt polycondensation method using the dicarboxylic acid component and the polyhydric alcohol component. For example, a direct esterification method in which the above components are directly reacted to evaporate water to esterify and polycondensate; or, a dialkyl ester of the dicarboxylic acid component is reacted with a glycol component to distill an alcohol to form an ester. It is prepared by a transesterification method in which a polycondensation is carried out while exchanging. In addition to the melt polymerization method, a solution polycondensation method, an interfacial polycondensation method, or the like may be employed.

The polyester polyol thus prepared preferably has a glass transition temperature of 40 ° C. or lower.
When the glass transition temperature of the polyester polyol is higher than 40 ° C., the adhesive strength between the coating layer and the base film or between the coating layer and the deposition layer may be reduced.

As the diisocyanates to be reacted with the polyester polyol thus obtained, any of aromatic, aliphatic and alicyclic diisocyanates can be used. For example, aromatic diisocyanates such as toluylene diisocyanate are preferred. The coating layer formed by the composition containing polyurethane obtained by using such an aromatic diisocyanate has high strength and excellent adhesion to a vapor deposited layer of the obtained coated film in the presence of water.

The above-mentioned polyester polyol is reacted with the above-mentioned diisocyanate by an ordinary method to obtain a polyurethane. Furthermore, it is also possible to react with a low molecular compound (chain extender) having two or more active hydrogens such as diols and diamines to extend the chain. As the diol, 1,
6-hexanediol and the like, and diamines such as ethylenediamine, hexamethylenediamine, and piperazine can be used. In particular, polyester urethane urea prepared using a diamine compound imparts favorable film strength to the coating layer.

In a preferred embodiment, among the urethane resins thus obtained, a substantially water-insoluble and water-dispersible thermoplastic polyurethane is used. Here, "substantially water-insoluble" means that the polymer does not dissipate in the hot water even when the polyurethane to be tested is immersed in hot water at 80 ° C. and stirred. More specifically, when the polyurethane to be tested is made into a chip and placed in a large excess of hot water (80 ° C.) and stirred for 24 hours, the weight of the polymer decreases by 5% by weight or less. It means that.

The resin composition forming these coating layers may further contain various additives. For example,
Inorganic inert particles such as silica, calcium carbonate, kaolinite, alumina, talc and barium sulfate; organic inert particles such as benzoguanamine-based resin and polystyrene-based resin (each having a particle size of about 0.01 to 10 μm), and these are added. By doing so, slipperiness and blocking resistance can be improved. Further, if necessary, a pigment; an organic or inorganic antistatic agent; a preservative; an antifoaming agent; The type and amount of the additive are not particularly limited as long as the interlayer adhesive strength of the obtained coated film with the deposited layer in the presence of water is not significantly impaired.

As a method of forming the resin coating layer on the base film, a method of simultaneously forming the base film and the coating layer resin composition using a film forming die equipped with a plurality of extruders; A method of forming a coating layer by melt-extruding a resin composition of a coating layer; a method of forming a base film and a resin composition of a coating layer into sheets, respectively, and then laminating them; or the above resin composition Any known method such as a method of applying the compound on a substrate film as a solution or a dispersion can be applied. In particular, a method of applying a solution or dispersion of the resin composition can be preferably used. Further, in consideration of safety, economy and the like, a method of applying an aqueous dispersion of the resin composition is most preferable.

First, the resin composition for forming the coating layer is formed into an aqueous dispersion by various methods. For example, a method of adding fine particles of the above resin composition and an emulsifier to water and dispersing them under strong stirring; when the above resin composition is a urethane-based resin, it has an isocyanate group at a terminal when synthesizing a polyurethane. A method in which a polyurethane (prepolymer), a chain extender, and an emulsifier are reacted with vigorous stirring in water to simultaneously perform dispersion and high molecular weight by mechanical shearing force; hydroxyl groups, amino groups, A method of imparting self-emulsifying properties by introducing an ionic group such as a carboxyl group and dispersing the same is used. Considering the water resistance of the obtained coating film, a method using no emulsifier is desirable. The above-mentioned various additives are added to the obtained dispersion of the resin composition as necessary, or these additives are appropriately added in the above-mentioned dispersion step to prepare a uniform aqueous dispersion.

The aqueous dispersion is applied on the base film by a known method. For example, the unstretched base film obtained by melt-extrusion, or the unstretched film is applied to the uniaxially or biaxially stretched base film, the dispersion liquid is applied, and further stretching and stretching as necessary. Post heat treatment is performed. Unstretched or coated with a dispersion on a base film stretched in a uniaxial direction, further uniaxially or biaxially stretched, and a biaxially oriented film obtained by heat treatment is used for the adhesion of the coating layer, such as economic efficiency. It is preferable from the point. In particular, from the viewpoint of workability, a method in which a dispersion liquid is applied onto a uniaxially stretched base film and then stretched in a direction perpendicular to the base film to obtain a biaxially stretched film is preferred. Roll coating method (gravure method, reverse method, etc.),
Known methods such as a knife coating method, a lot coating method, a nozzle coating method, and an air knife coating method can be employed. The amount of coating is determined according to the purpose. Usually, the amount of the resin composition present per unit area (m ² ) of the finally obtained coating layer obtained by performing biaxial stretching or the like is 0.01 to 5 g, Preferably, it is applied so as to be 0.02 to 1 g. If the amount of the resin composition is less than 0.01 g / m ² , the desired effect cannot be obtained, and if the amount exceeds 5 g / m ² , the obtained coated film tends to block. Further, when the obtained coated film is subjected to metal vapor deposition, there is a disadvantage that gloss of the vapor-deposited surface is lost when the metal film is subjected to hot water treatment. When applying the aqueous dispersion of the composition, the surface of the substrate film may be subjected to a corona treatment or a physical or chemical surface treatment, if necessary.

An inorganic substance is deposited on the surface of the coated polyester film of the present invention thus obtained. As the inorganic substance to be deposited, metals, metal oxides, inorganic oxides other than metals, and the like are used. As the metal, gold, silver, aluminum, zinc, tin, copper, nickel, iron, cobalt, chromium, manganese, palladium, titanium, indium and the like are used. Particularly, aluminum is widely used. A silicon oxide compound or the like is used as the inorganic oxide. These are used alone or in combination of two or more. These inorganic substances are deposited on the surface of the coating film of the coating film by a usual method. A vacuum deposition method or the like is preferably used.

The deposited polyester film thus obtained is used for various applications. In particular, on a vapor deposition layer obtained by vapor deposition of a metal or metal oxide on the coating layer, a sheet or film made of various resin materials can be laminated and suitably used as a food packaging material. Such a laminate does not peel even when immersed in hot water. As the resin material constituting the sheet or film to be laminated,
Polyethylene, polypropylene, various ionomers, ethylene-vinyl acetate copolymer, polyvinylidene chloride copolymer, polyester, polyamide and the like are used.

Thus, the coated polyester film of the present invention,
It is excellent in interlayer adhesion between the base material and the coating layer, and between the coating layer and the layer formed on the surface thereof, particularly, the deposition layer.
In particular, the coated polyester film of the present invention has excellent interlayer adhesion in the presence of hot water. Therefore, the vapor-deposited film of the present invention obtained by using this is extremely excellent in adhesion of the vapor-deposited layer, particularly in the presence of hot water. Therefore, the vapor-deposited film of the present invention is particularly suitably used as a food packaging film to be subjected to hot water sterilization and the like.

(Examples) Hereinafter, the present invention will be described with reference to examples. However, the method for producing the coated polyester film and the vapor-deposited film of the present invention is not limited to the following examples.

Example 1 (1) Preparation of vapor-deposited film: Hydran HW-340 (manufactured by Dainippon Ink) and Hydran HW-350 (manufactured by Dainippon Ink), which are water-dispersed polyester urethane ureas, were used. And the solids were mixed such that the weight ratio was 5: 5. To this mixture was added an equal volume mixture of ion-exchanged water and isopropyl alcohol, and the solids content was 5% by weight.
Was obtained.

Separately, polyethylene terephthalate is melt-extruded at 280 to 300 ° C and cooled with a cooling roll at 15 ° C to a thickness of about 150μ.
m of unstretched film was obtained. This unstretched film was stretched 3.5 times in the longitudinal direction between a pair of rolls at 85 ° C. having different peripheral speeds to obtain a base film. Next, the aqueous dispersion of the polyester urethane urea obtained above was applied to a substrate film by a roll coater method, dried with hot air at 70 ° C, and then stretched 3.5 times in the transverse direction at 98 ° C with a tenter, and further 200 times. It was heat-set at 〜210 ° C. to obtain a biaxially stretched coated polyester film having a thickness of 12 μm. The final coating amount of the coating agent (coating composition) was about 0.04 g / m ² . Aluminum was vapor-deposited to a thickness of 600 ° on the surface of the coating layer of the coating film to obtain a vapor-deposited film.

(2) Measurement of tensile elongation of the resin composition of the coating layer: The aqueous dispersion of polyester urethane urea prepared in the above (1) is applied on a flat polypropylene film, and is applied at normal temperature and pressure for 24 hours and then at 70 ° C. , Dried under reduced pressure for 12 hours,
A resin film having a thickness of about 0.3 mm was obtained. This was cut into a 10 mm width to obtain a test piece.

The above test piece was fixed to the chuck of a tensile tester Tensilon, manufactured by Toyo Baldwin Co., Ltd., the chuck interval was 50 mm, the pulling speed was 100 mm / min, and the measurement temperature was 60 ° C.
A tensile test was performed, and the elongation percentage immediately before breaking the test piece was defined as the tensile elongation. The tensile elongation of the coating resin composition thus measured is shown in Table 1 together with the tensile elongations of the coating resin compositions used in Examples 2 to 4, Comparative Examples 1 and 2 and Comparative Example 4 described later. .

(3) Performance evaluation of vapor-deposited film (a) Evaluation of boiling resistance of vapor-deposited film: An unstretched polypropylene (PP) sheet having a thickness of 60 μm was placed on the surface of the vapor-deposited layer of the vapor-deposited film obtained in the above item (1). After lamination by a dry lamination method, an aging treatment was performed. Two of the obtained laminates are stacked so that the PP layer is on the inside,
It was formed into a bag by the heat sealing method, and the bag was filled with water and air at a fixed volume ratio and sealed by the heat sealing method. Place the package in 95 ° C hot water for 30 minutes.
After standing for minutes, the mixture was cooled to room temperature, and the state of the package was visually observed. The percentage (%) of the package in which peeling was observed even a little was defined as the boil resistance of the deposited film. The results are shown in Table 1 together with the results of the deposited films of Examples 2 to 4 and Comparative Examples 1 to 4 described below.

(B) Evaluation of blocking resistance of coated film: ASTM-D using coated film before evaporating aluminum
The blocking resistance of the coated film was evaluated according to -918. The results are shown in Examples 2 to 4 and Comparative Example 1 described below.
The results are shown in Table 1 together with the results of the vapor deposition films of Nos. 1 to 4. The evaluation results are represented using the following symbols.

…: No stickiness…: almost no stickiness ×: considerably sticky Example 2 Except that hydran HW340 and hydran HW350 were mixed at a solid content weight ratio of 35:65, the same as in Example 1 was performed. A vapor deposition film was prepared.

Example 3 A vapor-deposited film was prepared in the same manner as in Example 1, except that Hydran HW340 and Hydran HW350 were mixed at a solid content weight ratio of 75:25.

Example 4 As polyester urethane urea, Hydran HW
A vapor deposition film was prepared in the same manner as in Example 1 except that only 340 was used.

Comparative Example 1 As polyester urethane urea, Hydran HW
A vapor deposition film was prepared in the same manner as in Example 1, except that only 350 was used.

Comparative Example 2 A vapor-deposited film was produced in the same manner as in Example 1 except that only hydran AP-10 (manufactured by Dainippon Ink Co., Ltd.), which is a water-dispersible polyester urethane, was used as the aqueous dispersion of the coating resin composition. Was prepared.

Comparative Example 3 A vapor deposition film was prepared in the same manner as in Example 1 except that the base film was not coated with the coating resin composition.

Comparative Example 4 A vapor-deposited film was prepared in the same manner as in Example 1, except that Elastron CT-7 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), which is a water-dispersible polyether urethane, was used as the aqueous dispersion of the coating resin composition. Prepared.

As is clear from Table 1, the packages prepared using the vapor-deposited films of Examples 1 to 4 of the present invention do not peel off even when treated with hot water and have good boil resistance. on the other hand,
In the deposited film of Comparative Example 1 in which the tensile elongation of the coating resin composition was less than 100%, the boil resistance was significantly reduced. Further, in Comparative Example 2 in which the tensile elongation of the coating resin composition exceeds 500%, the blocking resistance of the coating film is poor. Comparative Example 4 in which the coating layer was formed of a resin composition containing no segment having an ester bond in the molecule.
The vapor-deposited film has low adhesiveness between the coating layer and the base film, so that the heat-sealed portion is easily peeled off and the boil resistance is poor.

(Effect of the Invention) The coated polyester film of the present invention is thus
It is excellent in adhesion to a layer formed on the surface, particularly, an inorganic vapor deposition layer. Then, using this coated polyester film, a vapor deposited film having excellent adhesion between the vapor deposited layer and the base film in the presence of hot water can be obtained. Such a vapor-deposited film is suitably used particularly for a food packaging film subjected to a heat treatment with hot water.

Continuation of the front page (72) Katsuro Kuze, Inventor 10-24, Toyo-cho, Tsuruga-shi, Fukui Prefecture Toyobo Co., Ltd. Tsuruga Branch, Research Laboratory Co., Ltd. (56) References JP-A-2-50837 (JP, A) JP-A-Hei 2-50838 (JP, A) JP-A-63-209835 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1/00-35/00

Claims (2)

(57) [Claims] 1. A coated polyester film having a resin coating layer formed on at least one side of a base film made of a polyester resin, wherein the resin coating layer is formed of a resin composition containing polyester urethane urea as a main component. And a tensile elongation ε at 60 ° C. of a film made of the resin composition.
(%) 100 ≦ ε ≦ 500, coated polyester film. 2. A vapor-deposited film, wherein an inorganic vapor-deposited layer is provided on the surface of the resin coating layer of the coated polyester film according to claim 1.