JP2000143839A - Polyester film for molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester film for molding which has a good moldability, heat resistance and appearance and is suitable for mold processing, laminate mold processing or laminate mold processing wherein paper or a metal is a substrate or as containers. SOLUTION: The titled polyester film, wherein 93 mol% or more acid component composing the polyester comprises a terephthalic acid component and/or naphthalene dicarboxylic acid component, mainly comprises a polyester A satisfying the following formula I and II. Formula I: 55<MA+PA<=200 Formula II: -20<=MA-PA<=100. [Here, MA represents the concentration of residual catalytic metal element in polyester A (mmol%), and PA represents the concentration of residual phosphorus element in polyester A (mmol%)].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyester film for molding. Specifically, it is not only excellent in heat resistance, moldability, storage stability when used as a molding material that directly contacts the contents, but also in molding processing, especially paper,
The present invention relates to a polyester film for molding suitable for a laminate molding use and a container using a metal as a base material.

[0002]

2. Description of the Related Art Conventionally, in the case of flexible packaging, a polyester film used as a packaging material is laminated with polyethylene, polypropylene and an adhesive or without an adhesive, and a sealant layer is directly bonded to the contents. In order to make contact, little consideration has been given to contact between the polyester film and the contents.

However, in recent years, as packaging materials have been diversified and evolved, applications in which the polyester film comes into direct contact with the contents have increased, and it has been considered to improve the quality of the polyester film with an increase in shelf life.

[0004] In particular, when the contents are foods and beverages,
A case where a change in quality is recognized due to contact with the polyester film, for example, a change in taste of a beverage or food may be problematic because the value of the content is reduced as a product.

[0005] Among packaging materials, there are increasing cases where a polyester film is used for molding purposes, for example, the inner surface of a molded container. In this case, a metal and a polyester film are laminated with or without an adhesive and molded to obtain a can.

Conventionally, the inside and outside surfaces of metal cans are coated with a solution of various thermosetting resins such as epoxy or phenol dissolved or dispersed in a solvent for the purpose of corrosion protection, to coat the metal surface. Was widely done. However, such a method of coating the thermosetting resin requires a long time for drying the paint, and has unfavorable problems such as a decrease in productivity and environmental pollution due to a large amount of an organic solvent.

As a method of solving these problems, there is a method of laminating a film on a steel plate, an aluminum plate, or a metal plate which has been subjected to various surface treatments such as plating, which is a material of a metal can. When a metal can is manufactured by drawing or ironing a laminated metal plate of a film, the film is required to have the following characteristics. More recently, there is a demand for further improving the formability of the metal can. There is.

(1) Being excellent in laminating property to a metal plate. (2) Excellent adhesion to the metal plate. (3) It has excellent moldability and does not cause scratches, cracks, etc. after molding due to unevenness in film thickness, unevenness in orientation, etc. (4) The polyester film shall not peel, crack or pinhole due to impact on the metal can. (5) The flavor of the contents of the can is not degraded (hereinafter referred to as flavor).

Among these requirements, moldability and flavor are extremely important required characteristics, and many proposals have been made to solve the moldability and flavor.

For example, Japanese Patent Publication No. Hei 8-19245 discloses a film in which polyethylene terephthalate is copolymerized with isophthalic acid to reduce the melting point and the plane orientation coefficient.
Japanese Patent Application Laid-Open No. 9-241361 attempts to achieve both flavor and productivity by setting the contents of a catalyst metal and phosphorus in a specific range.

However, in the above-mentioned invention, when a film having a low orientation is obtained without sufficiently considering the metal component in the polyester, unevenness in the thickness and unevenness of the film becomes large, and it is unlikely to be a problem in ordinary molding. In addition, there has been a problem that when forming is performed at a high magnification, or when ironing is performed in addition to drawing, thickness deviation, scratches and cracks are likely to occur.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to enable forming and laminating, and in particular, high draw ratio drawing and drawing / ironing forming. An object of the present invention is to provide a polyester film for molding which is not only excellent in severe molding processability but also excellent in heat resistance and flavor.

[0013]

The object of the present invention is that at least 93 mol% of the acid component constituting the polyester comprises a terephthalic acid component and / or a naphthalenedicarboxylic acid component, and the following formulas (1) and (2) The present invention can be attained by a polyester film for molding, characterized by comprising polyester A satisfying the requirement (1) as a main component.

55 <MA + PA ≦ 200 (1) −20 ≦ MA−PA ≦ 100 (2) (where, MA in the formula is the concentration of the catalytic metal element remaining in the polyester A (mmol%), and PA is the polyester A
Shows the concentration (mmol%) of the elemental phosphorus remaining therein. )

As a result of intensive studies, the present invention has been found to be extremely excellent in moldability and heat resistance by limiting the structural units of the polyester and by setting the amounts of metal catalyst and phosphorus in specific ranges. Further, the present invention makes it possible to provide a molding polyester film having excellent flavor when filled with beverages, foods, and the like.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester constituting the polyester film of the present invention is a generic term for polymers having a main bond in the main chain as an ester bond, and is usually a polycondensation reaction of a dicarboxylic acid component and a glycol component. Can be obtained. Here, as the dicarboxylic acid component, for example, terephthalic acid, naphthalenedicarboxylic acid,
Aromatic dicarboxylic acids such as isophthalic acid, diphenyl dican rubonic acid, diphenyl sulfone dicarboxylic acid, diphenoxy ethane dicarboxylic acid, 5-sodium sulfone dicarboxylic acid, phthalic acid, oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, Examples thereof include aliphatic dicarboxylic acids such as maleic acid and fumaric acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and oxycarboxylic acids such as paraoxybenzoic acid. Also,
Examples of the glycol component include aliphatic glycols such as ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, and neopentyl glycol; polyoxyalkylene glycols such as diethylene glycol, polyethylene glycol, and polypropylene glycol; and fats such as cyclohexanedimethanol. Examples thereof include aromatic glycols, aromatic glycols such as bisphenol A and bisphenol S, and the like.

In the present invention, it is preferred that 93 mol% or more of the acid component constituting the polyester A is a terephthalic acid component and / or a naphthalenedicarboxylic acid component.
Necessary in terms of flavor. More preferably, 95 mol% or more of the acid component constituting the polyester is a terephthalic acid component and / or a naphthalenedicarboxylic acid component.

From the viewpoint of heat resistance and flavor, ethylene glycol is preferred among these glycol components, and 95% by mole or more of the glycol component constituting the polyester is preferably ethylene glycol.
It is more preferably at least 97 mol%.

The polyester film for molding in the present invention has a melting point of 246 to 2 in order to satisfy heat resistance and flavor.
Preferably it is 80 ° C.

The polyester film for molding of the present invention comprises:
In order to improve the thickness unevenness and orientation unevenness of the film, improve the moldability, and secure the flavor, the following formula (1) is used.
It is essential to satisfy (2).

55 <MA + PA ≦ 200 (1) −20 ≦ MA−PA ≦ 100 (2) (wherein MA is the concentration (mmol%) of the catalytic metal element remaining in the polyester A, and PA is the polyester A
Shows the concentration (mmol%) of the elemental phosphorus remaining therein. )

MA + PA is more preferably in the range of 60 to 180 mmol%, particularly preferably in the range of 65 to 150 mmol%. For MA-PA, -2
The range of 0 to 90 mmol% is more preferable, and
A range of 0 mmol% is particularly preferred.

The catalyst for producing the polyester of the present invention is not particularly limited, but may be an alkaline earth metal compound, a manganese compound, a cobalt compound, an aluminum compound, an antimony compound, a titanium compound, a titania / silica composite oxide, a germanium compound. Etc. can be used. Among them, an alkaline earth metal compound, a titanium compound, a titania / silica composite oxide, and a germanium compound are preferable in setting the catalytic activity, flavor, and the amount of the catalytic metal.

For example, when an alkaline earth metal or titanium compound catalyst is added as a catalyst, dimethyl terephthalate is reacted with ethylene glycol in the presence of the alkaline earth metal catalyst to form bishydroxyethyl terephthalate. , A method of adding a titanium compound catalyst and a phosphorus compound, and subsequently performing a polycondensation reaction at a high temperature under reduced pressure until a constant diethylene glycol content is obtained, to obtain a polyester having a specific catalyst metal amount and a phosphorus amount. .

The phosphorus compound added as a heat stabilizer is not particularly limited, but phosphoric acid, phosphorous acid and the like are preferable.

On the other hand, an alkali metal may be added within a range that does not impair the flavor. The total amount of the alkali metal element is preferably 10 ppm or less, more preferably 8 ppm.
Or less, particularly preferably 6 ppm or less.

In the present invention, the carboxylic acid concentration in the film preferably satisfies the following formula (3) from the viewpoint of improving the flavor.

15 ≦ C ≦ 45 (3) (where C represents the carboxylic acid concentration (equivalent / ton) in the film.) More preferably, 20 to 42 equivalent / ton, particularly preferably, 20 to 40. Equivalent / ton.

The polyester film for molding of the present invention comprises:
The plane orientation coefficient is 0.0 in terms of moldability and film strength.
It is preferably from 8 to 0.17, and in particular, in applications where it is used by lamination with a substrate such as paper or a metal plate, the plane orientation coefficient is preferably from 0.08 to 0.15, and more preferably from 0.08 to 0. .14. Here, the plane orientation coefficient is
When the refractive index in the longitudinal direction of the film is nMD, the refractive index in the width direction of the film is nTD, and the refractive index in the thickness direction of the film is nZD, the plane orientation coefficient Fn = (nMD + nTD) / 2−2
It is represented by nZD.

Further, in terms of moldability, the refractive index in the thickness direction n
It is preferable that ZD is 1.5 or more. In particular, it is preferably 1.51 to 1.55 in order to achieve both moldability and aging resistance.

It is preferable that particles are contained from the viewpoint of moldability and handling as a polyester film for molding, and the particle diameter and the amount of addition are not particularly limited. Particles having a particle size of 0.01 to 3 μm are
It is preferred that the content be contained by weight.

Specifically, examples of the inorganic particles include wet and dry silica, wet silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, mica, kaolin, and clay. Aluminum silicate, colloidal silica, etc. are preferred from the viewpoint of surface forming properties.

As the organic particles, various organic polymer particles can be used, and the type of the organic particles is not particularly limited as long as at least a part thereof is insoluble in the polyester. Further, as a material of such particles, polyimide, polyamide imide,
Various materials such as polymethyl methacrylate, formaldehyde resin, phenol resin, cross-linked polystyrene, silicone resin, and mixtures and copolymer resins thereof can be used, but particles having high heat resistance and uniform particle size distribution can be obtained. Particularly preferred are vinyl-based crosslinked polymer particles which can be easily obtained.

The polyester in the present invention preferably has a diethylene glycol content of 0.01 to 5 mol%,
More preferably, the content is 0.01 to 3 mol% in order to maintain excellent flavor even if subjected to many heat histories such as heat treatment and retort treatment of the molding material.

The polyester A has an intrinsic viscosity of 0.5
The intrinsic viscosity is preferably 0.6 to 1.0 for applications requiring heat resistance and aging resistance. Furthermore, the polyester film for molding of the present invention is preferably a laminated film in order to particularly improve moldability, heat resistance, and flavor. Although the laminated film is not particularly limited, it is preferable to laminate a polyester B satisfying the following formula (4) on at least one surface of a film mainly composed of polyester A in terms of flavor and heat resistance.

3 ≦ MB + PB ≦ 60 (4) (where MB is the concentration (mmol%) of the catalytic metal element remaining in the polyester B, and PB is the polyester B
Shows the concentration (mmol%) of the elemental phosphorus remaining therein. It is more preferable that MB + PB is 3 mmol% or more and less than 30 mmol%, and it is particularly preferable that MB + PB is 4 mmol% or more and less than 20 mmol%.

The thickness of the layer containing polyester B as a main component is not particularly limited, but is preferably 0.1 to 10 μm, and more preferably 0 to 10 μm, in order to improve the flavor while giving priority to moldability. The thickness is preferably from 3 to 8 μm, particularly preferably from 0.5 to 5 μm. Although the lamination structure is not particularly limited, A / B, A / B / A, B /
A / B and the like are preferred, and particularly the configurations of A / B and B / A / B are preferred in terms of flavor and heat resistance. In particular, it is preferable to use a layer mainly composed of polyester B so as to be in contact with the contents.

In the polyester film for molding of the present invention, the amounts of catalytic metal elements MB and G in polyester B are
It is preferable in terms of flavor that the total amount MB1 of e, Ti, and Si satisfies the following expression (5). 0.5 ≦ MB1 / MB ≦ 1 (5)

Further, it is preferable that particles are contained in the polyester B in order to improve the slip property and the abrasion resistance during molding, and particles having a shape index (major axis / minor axis) of 1.2 or more are used. It is particularly preferable to contain 0.005 to 0.5% by weight.

The film of the present invention has a thickness of 5 to 100 in terms of moldability, heat resistance and insulating properties after lamination on metal.
0 μm, more preferably 8 to 2 μm.
00 μm, particularly preferably 8 to 100 μm.

The method for producing a film in the present invention is not particularly limited. For example, after drying polyester as required, it is supplied to a known melt extruder, extruded into a sheet from a slit die, and subjected to electrostatic application. There is a method in which an unstretched sheet is obtained by closely adhering to a casting drum and solidifying by cooling.

The method of stretching and heat-treating the unstretched sheet in the longitudinal and width directions of the film to obtain a film having a desired refractive index in the thickness direction is particularly preferable in view of heat resistance and aging resistance. Preferably, a tenter method is preferable in terms of film quality.After stretching in the longitudinal direction, a sequential biaxial stretching method in which the film is stretched in the width direction, a simultaneous biaxial stretching method in which the film is stretched almost simultaneously in the longitudinal direction and the width direction. Is desirable. The stretching ratio is 1.5 to 1 in each direction.
It is 0.0 times, preferably 2.0 to 6.0 times. Either the stretching ratio in the longitudinal direction or the stretching ratio in the width direction may be increased, and may be the same. The stretching speed is from 1000% / min to 2%.
The stretching temperature is preferably from the glass transition temperature of the polyester to the glass transition temperature + 80 ° C.
If so, the temperature can be set to any temperature, but the glass transition temperature is preferably +20 to 60 ° C.

Further, after this, the film is subjected to a heat treatment, which is performed in an oven, on a heated roll, or the like.
It can be performed by any conventionally known method. The heat treatment temperature can be any temperature from 60 to 250 ° C, but is preferably from 150 to 240 ° C. The heat treatment time can be arbitrarily set, but is preferably 0.1 to 60 seconds, and more preferably 1 to 20 seconds.

The heat treatment may be performed while relaxing the film in the longitudinal direction and / or the width direction. further,
Re-stretching may be performed once or more in each direction, and then heat treatment may be performed.

It is preferable to further improve the adhesiveness by subjecting the film surface to a surface treatment such as a corona discharge treatment in order to improve the characteristics. At that time, E
The value is preferably 5 to 50, more preferably 10
~ 45. Here, the E value is the intensity of the corona discharge treatment, and is a function of the applied voltage (Vp), the applied current (Ip), the treatment speed (S), and the treatment width (Wt), and E = Vp × I
It is represented by p / S × Wt.

The film of the present invention may be coated with various coatings, and the coating compound, method and thickness are not particularly limited as long as the effects of the present invention are not impaired.

Further, the heat shrinkage when the film is heat-treated at 150 ° C. for 30 minutes is preferably 5% or less from the viewpoint of improving lamination property with metal. It is more preferably at most 4%, particularly preferably at most 3%.

The polyester film for molding of the present invention comprises:
It is used for molding materials, and the application is not particularly limited as long as it is a molding application, and examples thereof include soft packaging and containers made of a laminate obtained by laminating polyester. Among them, it is preferable to be used for forming processing such as bending, drawing, and ironing,
Further, it is more preferable that the application is performed after the lamination with the base material.

It is particularly preferred that the laminate substrate is a substrate selected from paper and metal. An adhesive or the like may be used between paper and metal as long as the properties are not significantly impaired, but it is preferable to directly bond the polyester film by heat without using an adhesive. A packaging material formed from a paper-polyester film or a metal-polyester film is also preferable from the viewpoint of flavor since the polyester film that causes a change in flavor can be reduced in thickness.

In this case, it is particularly preferable that the laminate substrate is made of metal from the viewpoints of barrier properties and sufficient heating, and is preferable because the protection of the contents is further improved.

Among these uses, it is particularly preferable to use them in molded containers containing beverages and foods.

The metal plate used in the present invention is not particularly limited, but is preferably a metal plate mainly composed of a material selected from iron and aluminum in view of formability.

Further, in the case of a metal plate made of iron, an inorganic oxide coating layer for improving adhesion and corrosion resistance on the surface thereof, for example, chromic acid treatment, phosphoric acid treatment, chromic acid / phosphoric acid treatment, electrolytic treatment A chemical conversion coating layer represented by chromic acid treatment, chromate treatment, chromium chromate treatment, or the like may be provided. Especially 5 to 20 as chromium in terms of metal chromium
0 mg / m ² chromium hydrated oxide is preferred,
A malleable metal plating layer, for example, nickel, tin, zinc, aluminum, gunmetal, brass, etc. may be provided. It is preferable that tin plating has a plating amount of 1 to ²⁰ mg / m ² , and nickel or aluminum has a plating amount of 1 to 25 g / m ² .

The paper used in the present invention is not particularly limited, but the pulp content is preferably 90% or more, and recycled paper may be used.

[0055]

The present invention will be described below in detail with reference to examples. The characteristics were measured and evaluated by the following methods.

(1) Alkali metal content The film was dissolved in orthochlorophenol, extracted with 0.5N hydrochloric acid solution, and determined by atomic absorption analysis. In the case of a laminated film, each layer was separated and obtained by scraping off each layer.

(2) Catalytic metal element amount, phosphorus element amount The film was heated to a melting point + 20 ° C. and melted to form a circular disk, and the amount of the catalytic metal element was determined by X-ray fluorescence analysis.
The phosphorus element amount was determined. In determining the amount, a calibration curve of X-ray fluorescence obtained from a sample in which the amount of each metal element added was changed in advance was used. The metal component due to the particles in the film was determined by removing the component. In addition, as a method of removing particles, for example, a film is heated at 80 to 100 ° C.
A method of dissolving the polymer in orthochlorophenol heated to a temperature above, performing a centrifugal separation operation, removing particles, and precipitating the polymer in the solution, and then performing the above-mentioned fluorescent X-ray analysis is known. In addition,
In the case of a laminated film, each layer was separated and obtained by scraping off each layer.

(3) Intrinsic Viscosity of Polyester Polyester is dissolved in orthochlorophenol and
Measured in ° C.

(4) Surface Orientation Coefficient of Film Using the Abbe refractometer with sodium D line (wavelength 589 nm) as a light source, the longitudinal refractive index nMD of the film,
The refractive index nTD in the width direction of the film and the refractive index nZD in the thickness direction of the film are obtained, and the plane orientation coefficient Fn = (nMD + nT
D) / 2-nZD was determined. In the case of the B / A / B laminated film, the B layer was scraped off.

(5) Average particle diameter and particle shape index A cross section of the film was cut into ultrathin sections, and 50 photographs were taken with a transmission electron microscope at a magnification of about 5,000 to 20,000 times, and the film was taken in polyester. The equivalent circle diameter of each dispersed particle was measured, and the average particle diameter was determined. For the shape index, the major axis and minor axis of each particle were determined, and the shape index (= major axis / minor axis) of each particle was determined and averaged.

(6) Carboxyl end group content of polyester The polyester was dissolved in o-cresol / chloroform (weight ratio: 7/3) at 100 ° C for 20 minutes, and potentiometric titration was performed with alkali. In the case of a laminated film, each layer was separated and obtained by scraping off each layer.

(7) Melting Point of Polyester The polyester was melted, rapidly cooled, and measured at a heating rate of 10 ° C./min with a differential scanning calorimeter (DSC2, manufactured by Perkin-Elmer Co.), and the melting point was determined from the melting peak. . In addition,
In the case of a laminated film, each layer was separated and obtained by scraping off each layer.

(8) Heat Shrinkage The shrinkage of the film treated in a hot air oven at 150 ° C. for 30 minutes was measured. The measurement was performed in the longitudinal direction and the width direction, and the value in the longitudinal direction (larger one) was described.

(9) Formability-1 (drawing and ironing properties) After laminating a film on both sides of a TFS (tin-free steel) steel plate (0.2 mm thick) heated at 60 m / min, it was heated with hot water at 60 ° C. After cooling, it was formed by drawing and ironing. Here, the temperature of TFS is set to 0.03 to 0.
04. A film having a plane orientation coefficient of 0 before lamination was thermally laminated at a temperature of melting point + 5 ° C. Thereafter, the laminated metal plate was molded at a reduction rate of 30%, and the appearance of the obtained can was observed with a microscope (magnification: 10 to 100 times), and the evaluation was made as follows.

A: No whitening, scratches or cracks in the film. ：: The film is slightly whitened, but there is no scratch or crack. Δ: The film was whitened and scratched, but there was no crack. ×: Whitening, scratches, and cracks are seen on the film.

(10) Formability-2 (Bendability) A polyester film was heat-laminated on both sides of paper and molded to form a container. Bending was performed to prepare a beverage pack. The paper portion of the obtained pack was removed, and the bent portion was observed under a microscope (magnification: 10 to 50 times) and judged as follows.

A: There is no whitening, scratches or cracks in the film. ：: The film is slightly whitened, but there is no scratch or crack. Δ: The film was whitened and scratched, but there was no crack. ×: Whitening, scratches, and cracks are seen on the film.

(11) Flavor A metal container having a polyester film laminated on its inner surface is filled with ion-exchanged water to which 1% lemon juice has been added, tightly wound and sealed, and stored at 40 ° C. for one month. went. After opening, 50 panelists made the following judgments compared with distilled water to which lemon juice for comparison was added.

◎: The number of persons who recognized a change in taste was 3 or less. ：: 4 to 6 persons who recognized a change in taste △: 7 to 9 persons who recognized a change in taste ×: 10 or more persons who recognized a change in taste

(12) Heat Resistance A 1% saline solution was filled in a metal container having a polyester film laminated on the inner surface side, and the container was tightly wound and sealed.
Furthermore, it heat-processed at 120 degreeC for 20 minutes, and what was aged at 65 degreeC for 1 week was dropped on concrete from a height of 30 cm, and the state of the film of an impact part was observed with a microscope (magnification 10 to 50 times). It was determined as follows.

A: No whitening, scratches or cracks in the film. ：: The film is slightly whitened, but there is no scratch or crack. Δ: The film was whitened and scratched, but there was no crack. ×: Whitening, scratches, and cracks are seen on the film.

Examples 1 to 6 and Comparative Examples 1 to 3 Films were formed using polyesters having the components, metal amounts and phosphorus amounts shown in Table 1.

In Example 1, a titanium compound catalyst, phosphoric acid and colloidal silica particles (average diameter 0.8 μm) were used as particles.
m), the polyester is polymerized, dried sufficiently in vacuum at 160 ° C., melt-extruded at 280 ° C., quenched and solidified on a cast while applying electrostatic force at 55 m / min with an electrode on the tape, and not stretched. A film was obtained. This unstretched film is heated at a temperature of 10 by a simultaneous biaxial stretching machine of a linear motor type.
Simultaneous biaxial stretching at 2 ° C (drawing ratio 2.8 times for both length and width,
(Stretching speed 3100% / min) and relaxation at 195 ° C 5
% For 3 seconds to obtain a 30 μm film.

In Example 2, the germanium oxide catalyst, phosphoric acid, and wet silica particles (average diameter 1.2 μm) were used as the particles.
m) was used to polymerize the copolymerized PET. Fully vacuum-dried at 160 ° C, melt-extruded at 280 ° C, formed a water film on the surface of the casting drum at 60 m / min, and quenched and solidified on the cast while applying static electricity with the electrode on the tape. A stretched film was obtained. The obtained unstretched film was formed with a tenter-type sequential biaxial stretching machine. The conditions at that time were a longitudinal stretching temperature of 96 ° C, a longitudinal stretching ratio of 3.4 times, a transverse stretching temperature of 115 ° C, a transverse stretching ratio of 3.3 times, and a heat treatment temperature of 185.
° C, 5% relax. Table 1 shows the obtained film properties.

In Example 3, the polyester was changed to a casting speed of 60 m / min, a longitudinal stretching temperature of 100 ° C., a longitudinal stretching ratio of 2.7 times, a transverse stretching temperature of 115 ° C., and a transverse stretching ratio of 2.8.
The heat treatment temperature is 180 ° C and the relaxation is 5%. Table 1 shows the obtained film properties.

In Examples 4 to 6, polyester B was used, and film forming conditions were changed, and a laminated film was formed successively by a biaxial stretching machine. In Example 4, an A / B two-layer laminated film was formed. In Examples 5 and 6, a B / A / B three-layer laminated film was formed.
The layer B was in contact with the laminate substrate. Table 2 shows the obtained film properties.

Comparative Examples 1 to 3 Films were formed in the same manner as in Example 3 except that the amount of the catalyst metal and the amount of phosphorus were changed. Table 3 shows the obtained film properties.

The film using the polyester film of the present invention was excellent in moldability, flavor and heat resistance.

[0079]

[Table 1]

[0080]

[Table 2]

[0081]

[Table 3]

The symbols in the table are as follows (numerical values are mol% in acid and glycol components). TPA: Terephthalic acid IPA: Isophthalic acid EG: Ethylene glycol DEG: Diethylene glycol CHDM: Cyclohexanedimethanol NDC: Naphthalenedicarboxylic acid M: Concentration of catalytic metal element remaining in film (mmol%) P: Phosphorous element remaining in film Concentration (mmol%) Ti / Si: titania / silica composite oxide Ti: titanium compound Ge: germanium compound Sb: antimony compound Ca: calcium compound

[0083]

The polyester film for molding of the present invention is excellent in moldability, heat resistance, and flavor. Among them, high-magnification molding, bending, lamination molding using paper and metal base, container Can be suitably used.

Continued on the front page F-term (reference) 4F071 AA45 AA84 AD06 AH05 BA01 BB06 BB08 BC02 BC10 4F100 AA20 AB01A AB01B AB01C AB01D AK41A AK41B AK41C AK42A BA01 BA02 BA03 BA04 BA06 BA10B BA10C BA10ABA19B01A23 GB01 JL08A JL08B JL08C YY00A YY00B YY00C

Claims (15)

[Claims] 1. A polyester A having a terephthalic acid component and / or a naphthalenedicarboxylic acid component comprising at least 93 mol% of an acid component constituting the polyester, and the polyester A satisfying the following formulas (1) and (2) as a main component. A polyester film for molding, characterized in that: 55 <MA + PA ≦ 200 (1) −20 ≦ MA−PA ≦ 100 (2) (where, MA is the concentration of the catalytic metal element remaining in the polyester A (mmol%), PA is the polyester A
Shows the concentration (mmol%) of the elemental phosphorus remaining therein. ) 2. The molding polyester film according to claim 1, wherein the melting point of the polyester is 246 to 280 ° C. 3. The polyester film for molding according to claim 1, wherein the carboxylic acid concentration in the film satisfies the following formula (3). 15 ≦ C ≦ 45 (3) (where C in the formula indicates the carboxylic acid concentration (equivalent / ton) in the film) 4. The polyester film for molding according to claim 1, wherein the plane orientation coefficient is 0.08 to 0.17. 5. The polyester film for molding according to claim 4, wherein the plane orientation coefficient is 0.08 to 0.14. 6. Particles having a particle size of 0.01 to 3 .mu.m
The polyester film for molding according to any one of claims 1 to 5, which contains from 0.5 to 0.5% by weight. 7. The polyester film for molding according to claim 1, wherein 95% by mole or more of the acid component constituting the polyester is terephthalic acid and / or naphthalenedicarboxylic acid. 8. The method according to claim 1, wherein 95% by mole or more of the glycol component constituting the polyester is ethylene glycol.
The polyester film for molding according to any one of claims 1 to 7. 9. A polyester film for molding obtained by laminating a polyester B satisfying the following formula (4) at a thickness of 0.1 to 10 μm on at least one surface of the polyester film according to claim 1. 3 ≦ MB + PB ≦ 60 (4) (where MB is the concentration (mmol%) of the catalytic metal element remaining in the polyester B, and PB is the polyester B
Shows the concentration (mmol%) of elemental phosphorus remaining therein. ) 10. The amount of catalytic metal element MB in polyester B
The polyester film for molding according to claim 9, wherein a total amount MB1 of Ge, Ti, and Si satisfies the following expression (5). 0.5 ≦ MB1 / MB ≦ 1 (5) 11. The polyester film for molding according to claim 9, wherein the polyester B contains 0.005 to 0.5% by weight of particles having a particle shape index (major axis / minor axis) of 1.2 or more. . 12. The polyester film for molding according to claim 1, which is formed after lamination. 13. The polyester film for molding according to claim 12, wherein the laminated substrate is a substrate selected from paper and metal. 14. The laminate substrate according to claim 13, wherein the laminate substrate is a metal.
The polyester film for molding according to 1. 15. The polyester film for molding according to claim 12, which becomes a container after molding.