KR100748929B1 - Easily formable polyester film - Google Patents

Abstract

Polyester A made up of at least two glycol components selected from ethylene glycol, butanediol and propanediol as a component, and the crystal melting temperature curve of polyester A in the DSC temperature measurement shows a substantially single peak. It has a melt peak temperature of 230 degreeC or more, and satisfy | fills following formula (1), The polyester film characterized by the above-mentioned. The film of this invention is suitable as a shaping | molding, processing, a printed product, or these process films.

M / P≤1 ‥‥‥ (1)

(Wherein M represents a concentration of the catalytic metal element remaining in polyester A (millimolar%), and P represents the amount of phosphorus remaining in polyester A (millimolar%).

Description

Polyester film which it is easy to mold {EASILY FORMABLE POLYESTER FILM}

This invention relates to the polyester film for shaping | molding, and can be used for various industrial materials, a packaging material, a building material, etc. Specifically, the present invention relates to a polyester film for molding suitable for surface coating of metal, wood, paper, resin and the like, and molding and embossing into containers such as lamination, cups and packs. The present invention also relates to an unstretched or biaxially stretched polyester film which is preferable as a process film such as a transfer printing support film used for in-mold transfer molding or the like which is simultaneously printed in molding.

Conventionally, the polyvinyl chloride film has been used as a cosmetic sheet etc. which are used by covering the surface of metal, wood, paper, resin, etc. from a viewpoint of workability. However, since polyvinyl chloride contains halogen elements in the polymer constituents, there are problems such as generation of toxic substances such as dioxins and bleed out of plasticizers when burned by incineration or fire. As the sound of environmental load reduction increases, new materials are required.

Also, it is used for plastic sheets such as furniture, building materials, electrochemical products, automobile interiors, containers, cosmetic sheets used for coating metal surfaces, transfer films for printing on surfaces, or transfer printing films. The support film has been required to be able to withstand bending, embossing and deep cross-sectional forming after forming or laminating into a complex three-dimensional shape by diversifying the necessity of extending the life of the product, handling and design. .

On the other hand, in Japanese Patent Laid-Open No. 3-67628, a biaxially stretched polyester film for molding having improved workability at 150 ° C. has been proposed, but is not satisfactory in terms of moldability at normal temperature, and furthermore, Although a polyester film copolymerized with a long-chain aliphatic dicarboxylic acid described in Japanese Patent Application Laid-Open No. 3-231929, Japanese Patent Laid-Open Publication No. 3-231930 and the like or a cycloaliphatic glycol or the like has been proposed, flexibility However, since heat resistance and solvent resistance fall, it was not fully satisfactory from the point of heat whitening in the molding process and solvent whitening at the time of printing. In addition, in the amorphous polyethylene terephthalate film called A-PET film, when forming and processing, the stress is high, and when forming at high temperature to lower the stress, wrinkles of the film due to softening and whitening due to crystallization occur. There was a problem.

An object of the present invention is to solve the problems of the prior art, and to provide a polyester film for molding not only excellent in environmental properties but also excellent in processing characteristics such as moldability and printability.

An object of the present invention described above is a film satisfying the following formula (1) using a polyester A made of at least two glycol components selected from ethylene glycol, butanediol and propanediol as constituents, and DSC temperature rising. The crystal melting temperature curve of the film in the measurement has substantially a single peak, and the melting peak temperature is achieved by a polyester film characterized by being 230 ° C or higher.

M / P≤1 ‥‥‥‥‥‥‥ (1)

(Wherein, M in the formula indicates the concentration of the catalytic metal element remaining in the polyester A (millimomol%), P represents the amount of phosphorus (millimomol%) remaining in the polyester (A).

Polyester A in the present invention is a structural unit of the polyester, at least two glycol components selected from ethylene glycol, butanediol and propanediol in terms of improving moldability, processability and printability. It is required to be polyester used above.

In the use which emphasizes especially moldability, workability, and printability, it is preferable that 40-90 mol% of the glycol component of polyester A is ethylene glycol. From the viewpoint of improving moldability and processability of 10 ° C or less, it is more preferable that 50 to 90 mol% of the glycol component of polyester A is ethylene glycol, and particularly preferably 60 to 85 mol% is ethylene glycol.

In order to improve moldability and processability of 100 ° C. or less, it is preferable that 10 to 60 mol% of the glycol component of polyester A is a glycol selected from butanediol and / or propanediol, and 10 to 50 mol% is butanediol. And / or glycol selected from propanediol, more preferably from 15 to 40 mol% is glycol selected from butanediol and / or propanediol. Butanediol and propanediol may be used together.                 

In particular, from the viewpoint of improving moldability, processability and printability, it is preferable to contain the entirety of ethylene glycol, butanediol and propanediol as glycol components. In that case, when mole% of ethylene glycol, butanediol, and propanediol is X, Y, and Z, respectively, it is preferable that X + Z-Y is 0 or more.

Moreover, as other glycol component, For example, Aliphatic glycol, such as a pentanediol, hexanediol, a neopentyl glycol; Alicyclic glycols such as cyclohexanedimethanol; Bisphenols (bisphenol A, bisphenol S, etc.), 1,3-bis (2-hydroxyethoxy), 1,2-bis (2-hydroxyethoxy) benzene, 1,4-bis (2-hydroxy Aromatic glycols such as ethoxy) benzene, bis [4- (2-hydroxyethoxy) phenyl] sulfone, 2,2-bis (4-β-hydroxyethoxyphenyl) propane, hydroquinone and resorcin; Diethylene glycol, polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol, etc. can be illustrated. It is preferable that the amount of diethylene glycol contained is 0.1-10 mol% from the point of moldability, workability, and printability, and 0.3-5 mol% from the point which does not deteriorate weather resistance.

Examples of the acid component of the polyester A include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfondicarboxylic acid, diphenoxyethanedicarboxylic acid and 5-sodium. Alicyclic dicarboxylic acids such as aromatic dicarboxylic acids such as sulfophthalic acid and phthalic acid, oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, aliphatic dicarboxylic acids such as maleic acid and fumaric acid, and cyclohexine dicarboxylic acid Oxycarboxylic acids, such as an acid and p-oxybenzoic acid, etc. can be illustrated. Terephthalic acid, isophthalic acid, adipic acid and the like can be preferably used in terms of heat resistance, moldability, processability and printability.                 

As means for containing at least two glycol component units selected from ethylene glycol, butanediol and propanediol in the polyester A of the present invention, a method of obtaining these copolymers by adding these glycols at the time of polymerization and a plurality of poly to an extruder The method of mixing and obtaining ester is illustrated. At this time, in the film using a copolyester, since solvent resistance, printability, heat resistance, etc. deteriorate, the film by mixing several polyester is preferable, and also PET (polyethylene terephthalate) and PPT (polypropylene tere) Phthalate) and PBT (polybutylene terephthalate) are preferable by mixing two or more kinds of resins selected from. Here, PET and PPT PBT also contain a low ratio copolymer of the acid component and / or glycol component, 20 mol% or less, more preferably 10 mol% or less, particularly preferably 5 mol% or less. Moreover, especially from the point of moldability, whitening resistance, etc., Preferably it is a mixture of PET and PPT, Especially preferably, it is mixed polyester which consists of 40-90 mol% of PET, and 10-60 mol% of PPT.

The polyester film of this invention is required for polyester A to satisfy following formula (1) after reducing heat resistance, solvent resistance, printability, and quality dispersion.

M / P≤1 ‥‥‥‥‥‥‥ (1)

(Wherein M represents the concentration of the catalytic metal element remaining in the polyester A (millimomol%), and P represents the concentration of the remaining element in the polyester A (millimomol%).)

Here, these metal element concentrations and phosphorus element concentrations are expressed as the concentration of about 1 unit (mol) of a repeating unit of polyester.

Preferably, M / P is 0.0001 or more and less than 1, More preferably, it is 0.001 or more and 0.8 or less, Especially preferably, it is 0.01 or more and 0.6 or less.

By controlling M / P ≦ 1, thermal stability can be increased, transesterification of the mixed polymer can be suppressed, and a decrease in melting point due to heat treatment can be suppressed. As a result, the above-described characteristics can be improved.

In the present invention, when producing polyester A, conventionally used reaction catalysts and coloring inhibitors can be used. Examples of the reaction catalysts include alkaline earth metal compounds, zinc compounds, lead compounds, manganese compounds, and cobalt compounds. , Aluminum compounds, antimony compounds, titanium compounds and the like can be used. Examples of the coloring inhibitor include phosphorus compounds and the like. Preferably, it is usually preferable to add an antimony compound, a germanium compound or a titanium compound as a polymerization catalyst at any stage before the production of the polyester is completed. As such a method, for example, a germanium compound may be used as a method of adding a germanium compound powder as it is, or as described in Japanese Patent Publication No. 54-22234, Germanium in the glycol component which is a starting material of polyester. The method of dissolving and adding a compound, etc. can be used.

As a germanium compound, for example, germanium dioxide, germanium hydroxide containing crystal water, or germanium tetramethoxide, germanium tetraethoxide, germanium tetrabutoxide, germanium ethylene glycoside, such as germanium alkoxide compound, germanium phenolate, germanium Germanium phenoxide compounds such as β-naphthalate, phosphorus-containing germanium compounds such as germanium phosphate and germanium phosphite, and germanium acetate can be used. Among these, germanium dioxide is preferable.

Although it does not specifically limit as an antimony compound, For example, antimony oxides, such as antimony trioxide, antimony acetate, etc. can be used.

Although it does not specifically limit as a titanium compound, Alkyl titanate compounds, such as tetraethyl titanate and tetrabutyl titanate, the composite oxide of the element chosen from titanium, a silicon, a zirconium, an aluminum element, etc. can be used preferably.

Although the phosphorus compound added as a heat stabilizer to the polyester in this invention is not specifically limited, Phosphoric acid, phosphorous acid, phosphate ester, etc. are preferable.

In particular, a phosphorus compound having a molecular weight of 300 or more, particularly preferably 400 or more is preferably used in view of suppressing bleed-out during film production. Examples of the phosphorus compound having a molecular weight of 300 or more include, for example, stearyl phosphate, triphenyl phosphate, tricresyl phosphate, trixenyl phosphate, and glycidyl diphenyl phosphate, but stearyl phosphate is preferable in terms of suppressing bleed-out. Do.

The content (participation amount) of the phosphorus compound added in the polyester A is preferably 20 to 1000 mmol% of phosphorus compound as a small amount of phosphorus in terms of thermal stability and color tone, more preferably 90 to 900 mmol%, Especially preferably, it is the range of 120-800 mmol%.

In addition, the method of adding a phosphorus compound may be any of the method of adding at the time of superposition | polymerization, the method of supplying and adding with a polymer to an extruder. Generally, when a large amount of phosphorus compound is added during the polymerization, the polymerization reaction is inhibited. Therefore, a method of feeding and adding to the extruder together with polyester in the range of M / P >                 

In the polyester film of this invention, it is necessary for the crystal melting curve of the film in DSC temperature measurement to show a substantially single peak.

If the peak of the crystal melting curve of the film indicates two or more, since the molecular structure in the copolymer or the mixture is not uniform, dispersion of elongation is increased and moldability and whitening resistance are poor. There may be a case.

Here, the peak of the crystal melting curve in the present invention is the crystal melting peak attributable to the polymer constituting the film, and the film (5 mg) was measured at 20 ° C./min in a nitrogen atmosphere under a nitrogen atmosphere in DSC. Is the minimum point of the endothermic curve obtained from the DSC curve, i.e., the derivative value becomes zero. Moreover, the peak of an independent crystal melting curve is also made for the shoulder peak (minimum point of a peak) of 20 J / g or more of heat of fusion overlapping one endothermic curve. That is, to display a substantially single peak as used in the present invention means that there is only a single minimum point of the crystal melting peak of 2 J / g or more of heat of fusion.

 It is necessary for the peak point temperature of the crystal melting curve of the polyester film which concerns on this invention to be 230 degreeC or more from a heat resistant point. More preferably, it is 235-260 degreeC, Especially preferably, it is 244-255 degreeC.

It is preferable that the intrinsic viscosity of polyester A is 0.5-1.5, It is further more preferable that intrinsic viscosity of polyester A is 0.6-1.3, In particular, in the use which requires a thin film in moldability and workability, It is especially preferable that is 0.7-1.0.

It is preferable that the polyester film of this invention is 800 degreeC or more in average breaking elongation of the film in 80 degreeC from the point which makes various moldability and workability favorable. Here, the average elongation at break of the film is 10 times the elongation at break in the longitudinal and transverse directions when a 10 mm wide and 100 mm long film is stretched at 300 mm / min. Except, averaged. It is more preferable that average breaking elongation in 80 degreeC is 900% or more, and it is especially preferable that it is 1000% or more and 2000% or less.

It is preferable that the polyester film which concerns on this invention contains 1-60 weight% of plasticizers whose molecular weight is 3000 or less from the point which improves moldability and workability further, and improves the flexibility of a film. It is preferable to contain 5-60 weight% of plasticizers whose molecular weight is 3000 or less from a point which improves especially flexibility. Moreover, as a plasticizer, it is preferable that a solidification point is 30 degrees C or less, More preferably, it is 20 degrees C or less, Especially preferably, it is 10 degrees C or less.

Although it does not specifically limit as a kind of plasticizer, It is a compound of molecular weight 3000 or less, As the kind, adipic acid plasticizer, phosphorus plasticizer, polyether plasticizer, trimellitic acid plasticizer, phthalic acid plasticizer, etc. can be used. It is preferable that these plasticizers introduce | transduce the functional group functional group blocking group which suppresses reaction with polyester A. Especially as a plasticizer used for this invention, an ester plasticizer is preferable at the point of heat resistance and moldability. As ester plasticizer, it is preferable that hydroxyl value is 0-20 (mg / g) from a heat resistant point, and it is more preferable that it is 0-15 (mg / g). As an acid value, 0-5 (mg / g) is preferable and it is especially preferable that it is 0-3 (mg / g).

Moreover, as a method of adding a plasticizer, the method of adding collectively before or after a polymerization reaction, the method of using a vent type extruder, the method of adding using a liquid feeding pump from a screw or a pipe wall, etc. are illustrated.

In the present invention, when the polyester B layer is compounded on at least one side of the layer A containing the polyester A as a main component, new functions such as bleed out resistance of plasticizer, handling property, non-adhesiveness during processing, or heat adhesiveness It is more preferable at the point which gives.

The layer A containing polyester A as a component and the layer B containing polyester B as a component may be arbitrarily combined. For example, it can be compounded such as polyester A / polyester B, polyester A / polyester B / polyester A, polyester B / polyester A / polyester B, and the like. At this time, in particular, polyester A / polyester B in which polyester B is laminated on at least one side is more preferable in terms of improving the bleed-out resistance of the plasticizer exemplified above, handling property, non-adhesiveness during processing, or thermal adhesiveness. Preferably, the structure of polyester B / polyester A / polyester B which laminated polyester B on both surfaces is preferable.

As the acid component of the polyester B, for example, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfondicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sodium Alicyclic dicarboxylic acids such as aromatic dicarboxylic acids such as sulfoisophthalic acid and phthalic acid, oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, aliphatic dicarboxylic acids such as maleic acid and fumaric acid, and cyclohexine dicarboxylic acid Oxycarboxylic acids, such as a carboxylic acid and P-oxybenzoic acid, etc. can be illustrated. Terephthalic acid, isophthalic acid, adipic acid and the like can be preferably used in terms of heat resistance, moldability, processability and printability.                 

As a glycol component of polyester B, For example, Aliphatic glycol, such as ethylene glycol, a propanediol, butanediol pentanediol, hexanediol, and neopentyl glycol; Alicyclic glycols such as cyclohexanedimethanol; Bisphenols (bisphenol A, bisphenol S, etc.), 1,3-bis (2-hydroxyethoxy), 1,2-bis (2-hydroxyethoxy) benzene, 1,4-bis (2-hydroxy Aromatic glycols such as ethoxy) benzene, bis [4- (2-hydroxyethoxy) phenyl] sulfone, 2,2-bis (4-β-hydroxyethoxyphenyl) propane, hydroquinone and resorcin; Diethylene glycol, polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol, etc. can be illustrated. It is preferable that the quantity of diethylene glycol contained is 0.1-10 mol% from the point of moldability, workability, and printability, and also 0.3-5 mol% from the point which does not deteriorate weather resistance.

It is preferable that the intrinsic viscosity of polyester B is 0.5-1.5, It is more preferable that it is 0.6-1.3, It is especially preferable that it is 0.7-1.0 for the use which especially moldability and workability are calculated | required.

In addition, polyester B is preferably M / P ≤ 1 like polyester A, more preferably M / P is in a range of 0.0001 or more but less than 1, more preferably 0.001 or more and 0.8 or less, particularly preferably. It is 0.01 or more and 0.6 or less.

In particular, the thickness of the polyester B layer is preferably 0.1 µm or more and 1 mm or less in terms of improving the bleed-out resistance of the plasticizer, the handleability of the film, and the non-tackiness during processing. More preferably, they are 1 micrometer or more and 1 mm or less.

In addition, in this invention, you may add particle | grains to each layer in order to improve the handling and workability of a film.                 

Specifically, as inorganic particles, wet and dry silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, mica, kaolin, clay, titanium oxide, zirconia, hydroxyapatite and the like can be used. Can be.

In addition, although various organic polymer particles can be used as organic particle | grains, as long as at least one part is particle | grains which are insoluble with respect to polyester, you may be a particle of what kind of composition. In addition, various materials such as polyimide, polyamideimide, polymethyl methacrylate, formaldehyde resin, phenol resin, crosslinked polystyrene, silicone resin and the like can be used as raw materials for such particles. Particularly preferred are vinyl-based crosslinked polymer particles and crosslinked polystyrene particles in which uniform particles are easily obtained.

Particles are added to polyester A and / or polyester B, and the average particle diameter of the particles is preferably 0.01 to 10 µm, and particularly for applications in which workability is important, the particles having an average particle diameter of 0.1 to 5 µm are contained. It is preferable.

When adding particle | grains to each layer, it is preferable that it is 0.01-70 weight% as an addition amount of particle | grains.

Moreover, it is also good to make each layer contain the component which provides low surface energy property, such as a wax and silicone, and as an addition amount, 0.01-1 weight% is preferable in each layer.

In view of improving the beauty, it is preferable to use a filter that blocks coarse and coarse particles or foreign substances of 30 μm or less, and particularly, a filter that blocks 20 μm or less when melt-extruding a thermoplastic composition. It is preferable to use.                 

In addition, in order to reduce the odor during molding and processing, and to reduce the odor as a product, the content of acetaldehyde in the film is preferably 100 ppm or less, more preferably 50 ppm or less, particularly preferably 30 ppm or less. It is preferable.

The method of lowering the content of acetaldehyde in the film is not particularly limited. For example, in order to remove acetaldehyde generated by pyrolysis when the polyester is produced by a polycondensation reaction or the like, the polyester is subjected to reduced pressure or Under an inert gas atmosphere, a method of heat treatment at a temperature below the melting point of the polyester, preferably a solid-phase polymerization of the polyester at a temperature of 150 ° C. or higher and a temperature below the melting point under a reduced pressure or an inert gas atmosphere, using a vented extruder The method of melt-extruding, the method of melt-extruding a polymer, and the method of extruding in a short time by reducing extrusion temperature as much as possible can be used.

Although it does not specifically limit as a manufacturing method of the polyester film which concerns on this invention, Taking the case where a particle enters as polyester A and mixes polyethylene terephthalate, a polypropylene terephthalate, and a polybutylene terephthalate, the polyester is The mixture and, if necessary, the phosphorus compound are undried or dried, and then supplied to a single or double screw melt extruder, extruded from a slit-shaped die into a sheet, dropped between nip rolls, adhered to a casting drum, and cooled and solidified. Get a sheet. Under the present circumstances, it is preferable at the point which produces the film of 150 degrees C or less to make small nip roll and high temperature of roll temperature. In the small hardening of a nip roll, 400 mm or less of diameter is preferable, and 300 mm or less are especially preferable. As high temperature of roll temperature, 40 degreeC or more and 150 degrees C or less are preferable, and 50 degreeC or more and 140 degrees C or less are more preferable. A product obtained by winding a roll surface in a roll sheet shape to obtain a non-adhesive film is roughened.

In addition, since the adhesion to the casting drum by the electrostatic application method is stable and can be cooled, it can be used more preferably from the viewpoint of maintaining the planarity during heating processing.

It is preferable to manufacture an unstretched film as mentioned above in the use which emphasizes moldability and workability especially.

On the other hand, in the use which emphasizes heat resistance, there exists a method of extending | stretching and heat-processing this unstretched sheet to the longitudinal direction and / or the width direction of a film as needed, and obtaining the film which has the target elongation at break. Preferably, in terms of the quality of the film, it is preferable to use a tenter method, and a sequential biaxial stretching method for stretching in the longitudinal direction and then stretching in the width direction, and a simultaneous biaxial stretching method for stretching the longitudinal direction and the width direction almost simultaneously. desirable. As a draw ratio, Preferably it is 1.5 to 5.0 times, More preferably, it is 1.5 to 4.0 times in each direction. Elongation ratio of a longitudinal direction and a width direction may be enlarged, and may be the same. In addition, the stretching speed is preferably 1000% / min to 1000000% / min, and it is particularly preferable to form the stretch rate at 300000% / min or less. Although extending | stretching temperature can be arbitrary temperature as it is 100 degreeC or more and 150 degrees C or less, Glass transition temperature +20 degreeC-60 degreeC is preferable.

Next, although heat processing of a film is performed after this, this heat processing can be performed by arbitrary methods conventionally known, such as the roll shape heated in oven. Although heat processing temperature can be arbitrary temperature of 60 degreeC or more and 250 degrees C or less, Preferably they are 150 degreeC-240 degreeC. Moreover, although heat processing time can be arbitrarily selected, 0.1 to 60 second is preferable, More preferably, it is 1 to 20 second.

The heat treatment may be performed while the film is relaxed in the longitudinal direction and / or the width direction. In addition, redrawing may be performed once or more in each direction, and heat processing may be performed after that.

It is preferable that the thickness of the polyester film which concerns on this invention is 10-2000 micrometers from a moldability and workability point, More preferably, it is 20-1000 micrometers.

In order to improve workability and adhesiveness, the polyester film of the present invention may be subjected to corona discharge treatment, coating treatment or the like again before winding or after winding, if necessary. At this time, the surface energy is preferably 40 to 60 mN / m, more preferably 45 to 60 mN / m.

The polyester film according to the present invention is preferably used as an unstretched film in the case of focusing on formability and processability. However, when used in uniaxial stretching or biaxial stretching, the surface orientation coefficient is 0.03 to It is preferable that it is 0.14. In particular, in applications where the film formability and heat resistance of the film are required, the plane orientation coefficient is preferably 0.03 to 0.145, more preferably 0.04 to 0.14, and particularly preferably 0.05 to 0.13. Here, the plane orientation coefficient is the plane orientation coefficient fn = (n _MD + n _TD ) / when the longitudinal direction refractive index of the film is n _MD , the width direction refractive index of the film is n _TD , and the thickness direction refractive index of the film is n _ZD . It is represented by 2-n _ZD .

As the use of the polyester film according to the present invention is excellent in formability, processability and printability, the polyester film is used for forming and processing in a laminated structure with a single body, a nonmetal or a metal material, and the purpose of use is particularly limited. Although not used, if the nonmetallic material is paper, nonwoven fabric, glass, or polymer material, it is preferable in terms of weight reduction of the final product. On the other hand, in the use which requires the strength of a material, it can use with the structure which laminated | stacks a metal or glass reinforced polymer and this film.

The polyester film which concerns on this invention may melt | fuse a part with heat, and may adhere | attach with another raw material, and may form an adhesive layer in the film of this invention or another raw material beforehand. Moreover, in a laminated structure, the contact bonding layer, the printing layer, etc. may be formed between another raw material.

As the molding and processing method, lamination, vacuum molding, compression molding, vacuum compression molding, drawing molding, bending molding, molding or a combination of these and other processing methods may be performed alone or in plurality. The processing method is not particularly limited.

In the case of being used alone, molding processing such as vacuum molding, press molding, vacuum press molding, drawing molding, bending molding, stretch molding, or the like may be carried out once or a plurality of times, and the molding processing method is not particularly limited.

Hereinafter, the present invention will be described in detail by way of examples. In addition, all the characteristics were measured and evaluated by the following method.

(1) intrinsic viscosity of polyester

The polyester was dissolved in orthochlorophenol and measured at 25 ° C.

(2) Solvent Metals in Polyester

Obtained by dose fluorescence X-ray analysis. In addition, quantification was performed by preparing the sample which contained a fixed amount each metal element, and preparing the analytical curve.

(3) Melting point of polyester film

When 5 mg of polyester film samples were measured using a differential scanning calorimeter RDC220 type manufactured by Seiko Denshi Kogyo Co., Ltd. at a temperature of 20 ° C./min after holding at −30 ° C. for 5 minutes under a nitrogen atmosphere. The minimum point (that is, the point at which the derivative value becomes zero) of the endothermic curve obtained from the DSC curve was taken as the crystal melting peak temperature. Moreover, the peak of an independent crystal melting curve was also made for the shoulder peak (minimum point of a peak) whose heat of fusion partially overlapping one endothermic curve is 2 J / g or more. In addition, about the laminated | multilayer film, 5 mg of polyester of each layer was extract | collected on one edge, and it measured similarly.

(4) the refractive index of the film

Sodium D-ray (wavelength 589 nm) was measured using an Abbe refractometer as a light source. The plane orientation coefficient is the plane orientation coefficient fn = (n _MD + n _TD ) / 2 when the longitudinal refractive index of the film is n _MD , the widthwise refractive index of the film is n _TD , and the thickness of the film is n _ZD . -n _ZD .

(5) Average particle diameter

The cross section of the film was cut to prepare a very thin section, photographed at a magnification of about 5000 to 20000 using a transmission electron microscope, the circular equivalent diameter of each particle dispersed in polyester A was measured, and the average particle diameter was determined.

(6) Average breaking elongation

 It measured at 80 degreeC using the tensileron (tension tester). In the measurement, the film was kept at the measurement temperature for 30 seconds, and the tensile velocity was 300 mm / min, the width was 10 mm, and the sample length was 50 mm. Ten points of breaking elongation (%) in the film length direction and the width direction were respectively measured and averaged. Saved.

(7) Formation of pressure

The temperature was changed to 80-130 degreeC, and the moldability was judged by the press molding machine. The state at the time of shaping | molding at the most favorable temperature conditions was determined as follows.

(Double-circle): The corner was also shape | molded distinctly and the thickness after shaping | molding was also uniform.

O: Although the corner had a slightly rounded shape, the thickness after molding was uniform.

(Triangle | delta): There existed a slightly rounded shape in a corner, and the thickness after molding was a little nonuniform.

X: The thickness after shaping | molding was nonuniform, wrinkled, or whitened.

(◎, O, △ pass, X fail.)

(8) printability                 

A solvent-based ink containing ethyl acetate and toluene was gravurely applied and dried at 80 ° C. to confirm appearance.

◎: No whitening, good beauty

O: A little whitening is visible but no beauty problem

(Triangle | delta): Whiteness is seen and a beautifulness falls.

×: large whitening, appearance changes significantly

(◎, O, △ pass, X fail.)

(9) embossing processability

The polyester film of the present invention and a commercially available PET biaxially stretched film ("Rumira" manufactured by Higashiregakushiki Co., Ltd., S type 75 µm) were bonded with a urethane-based adhesive using ethyl acetate as a solvent, at 80 ° C. After drying, the polyester film side of the present invention was heated by roll heating (100 ° C.) and direct heating by condensing radiation, and after passing through an embossing roll (unevenness of 50 μm in height), a cooling roll (40 ° C.) )). The radial heating setting was changed and evaluation in the best state was performed. The embossing property of the obtained film was determined as follows. In addition, beautifulness was determined by the absence of color change, wrinkles, and no glare.

(Double-circle): The uneven | corrugated shape of an embossing roll is formed in the film side favorably, and the beauty is also favorable.

O: The large part of the uneven | corrugated shape of emboss roll is formed in the film side favorably, and there is little change in aesthetics.                 

(Triangle | delta): Although the uneven | corrugated shape of an embossing roll is formed in the film side, a little unevenness | corrugation is less. The change of beauty is also recognized.

X: Although the uneven | corrugated shape of an embossing roll is formed in the film side, unevenness | corrugation is less and the change of aesthetics is also large.

(◎, O, △ pass, X fail.)

(10) Whitening resistance

The film was heat-treated at 110 ° C. for 3 minutes in a hot air oven to determine whitening properties.

(Double-circle): There is also no whitening, and transparency is favorable.

O: A little whitening is seen, but transparency is good.

(Triangle | delta): There is no problem in use, but a whitening is seen remarkably.

X: Great whitening and opacity.

(◎, O, △ pass, X fail.)

(11) thermal stability

A sample of 5 mg of polyester film was taken, and measured using a differential scanning calorimeter RDC220 manufactured by Seiko Denshi Kogyo Co., Ltd. at a temperature rising rate of 20 ° C./min from -30 ° C. to 280 ° C. under a nitrogen atmosphere ( 1stRun), it was kept at 280 ° C for 20 minutes, and then quenched to -30 ° C in liquid nitrogen, and then measured (2ndRun) at a temperature rising rate of 20 ° C / min to 280 ° C.

Also about laminated | multilayer film, it measured as it is, without dividing each layer, and the melting point difference (DELTA) Tm (= Tm1-Tm2) was calculated | required that melting | fusing point Tm1 measured by 1stRun and melting point Tm2 measured by 2ndRun are substantially single peak.

◎: ΔTm ≤7

O 7 ΔTm ≤ 15

×: 15 <△ Tm

(◎, O is passed and × is failed.)

The detail of the polyester used by the Example is described below. Table 1 also shows a list of these, catalytic metal element amount, small element amount, intrinsic viscosity, and the like.

[PET (1) (phosphorous high molecular weight polyethylene terephthalate)]

After transesterification was carried out by adding a manganese catalyst as a catalyst to dimethyl terephthalate and ethylene glycol, a polycondensation reaction was performed for 6 hours by adding antimony trioxide as a polymerization catalyst and phosphoric acid as a heat stabilizer to obtain a polyester composition PET (1). (Catalytic metal element content: 70mmol, personnel content: 100mmol%, intrinsic viscosity 0.71).

[PET (2) (normally polyethylene terephthalate)]

After carrying out transesterification by adding a manganese catalyst as a catalyst to dimethyl terephthalate and ethylene glycol, a polycondensation reaction was carried out by adding antimony trioxide as a polymerization catalyst and phosphoric acid as a heat stabilizer for 4 hours to obtain a polyester composition PET (2). (Catalytic metal element content: 70mmol, personnel small amount: 20mmol%, intrinsic viscosity 0.73).

[PPT (polypropylene terephthalate)]

To the dimethyl terephthalate and 1,3-propylene glycol, a titanium catalyst was added as a catalyst to carry out a transesterification reaction, and then a polycondensation reaction with phosphoric acid as a heat stabilizer was carried out to obtain a polyester composition PPT (catalyst metal element amount: 13 Millimolar%, small capacity: 3 mmol%, intrinsic viscosity 0.90).

[PPT / I ¹⁰ (10 mole% isophthalic acid copolymerized PPT)]

According to the synthetic approach of the PPT, isophthalic acid copolymerization amount to obtain a polyester composition PPT / I ¹⁰ copolymerizing 10 mol% (the catalyst metal element amount: 13 mmol%, a small amount personnel: 3 mmol%, an intrinsic viscosity of 0.85).

[PBT (polybutylene terephthalate)]

Titanium catalyst was added to dimethyl terephthalate and 1,4-butanediol as a catalyst and subjected to a transesterification reaction, followed by a polycondensation reaction with an impression as a heat stabilizer to obtain a polyester composition PBT (catalytic metal element amount: 50 mmol). %, Small capacity: 30 mmol%, intrinsic viscosity 1.0).

[PET / CHDM ³⁰ (Cyclohexanedimethanol 30mol% copolymer PET)]

Dimethyl terephthalate, ethylene glycol, cyclohexanedimethanol by methanol, to obtain a PET / CHDM ³⁰ (a catalytic metal element amount: 80 mmol%, a small amount personnel: 80 mmol%, an intrinsic viscosity of 0.75).

[PIB (Isophthalic Acid Copolymer)]

10 mol% terephthalic acid, 90 mol% isophthalic acid, 90 mol% ethylene glycol, 2 mol% diethylene glycol, 8 mol% 1,3-bis (2-hydroxyethoxy) benzene Copolymerized polyester PIB Small amount: 70 mmol%, small number of people: 20 mmol%, intrinsic viscosity 0.8) was synthesized.

 Polyester  Catalytic metal Catalytic Metal M (mmol%) Personnel quantity P (millimolar%)  Intrinsic viscosity PET (1) Mn, Sb 70 100 0.71 PET (2) Mn, Sb 70 20 0.73 PPT Ti 13 3 0.90 PPT / I ¹⁰ Ti 13 3 0.85 PBT Ti 50 30 1.00 PET / CHDM ³⁰ Mn, Co 80 80 0.75 PIB Mn, Sb 40 20 0.80

[Preparation of Particle Containing PET]

Crosslinked polystyrene particles (average particle diameter 6 mu m), silicon particles (average particle diameter 5 mu m), and aggregated silica (average particle diameter 1.7 mu m) were prepared. The above PET (1) and PET (2) were installed in two vacuum vents (5 Torr) by a twin screw extruder and melted to obtain particle-containing PET added 5 wt% to each.

Hereinafter, the film preparation example of the film of this invention and its characteristic are shown. In addition, the content which is not described in the text from the point of a film composition, a characteristic, etc. is as showing to Tables 2-6.

Example 1

PPT, PET, and particle-containing PET obtained as described above were tip mixed so as to have the composition shown in Table 2. Thereafter, vacuum drying at 150 占 폚 was applied to the extruder (280 占 폚), melted, discharged from the detention (270 占 폚) by a conventional method, and then cooled and solidified in a mirror-cooling drum (25 占 폚) with electrostatic application to 100 占 퐉. An unstretched film was obtained. Table 2 shows the physical properties, moldability, printability and processability of the obtained film. As it turns out from Table 2, it turned out that it is excellent in moldability, printability, and workability.

Example 2

The composition of the particles and the polyester is mixed as shown in Table 2, and the stearyl phosphate (AdekastabAX-71, molecular weight 490, manufactured by Asahi Denka Kogyo Co., Ltd.) at the time of melt extrusion is measured by a feeder in an undried state. The mixture of polyester was fed to a twin screw extruder (holding three vacuum vents (5 Torr) in the zone after the melting of the polyester) in a constant amount feeder, melt extrusion at 270 ° C., and a slit phase from the detention (270 ° C.). The polymer shown was cast into a nip roll (250 mm in diameter) in a cooling drum at 50 ° C. Other than this was carried out similarly to Example 1, and obtained 100 micrometers unstretched film. In particular, the thermal stability became good.

Example 3

Mix the amounts of polyester and stearylphosphoric acid so as to have the composition shown in Table 2, add polyethylene glycol dibenzoic acid ester (molecular weight 600) in 5% by weight liquid as a plasticizer, and set the cooling drum temperature at the time of casting to 10 ° C. A film production was carried out in the same manner as in Example 2 except for the above. In particular, workability became favorable.

Example 4

The addition amount of the plasticizer used in Example 3 was 10 weight%, and the mixing amount of polyester and stearyl phosphoric acid was changed so that it might become a composition shown in Table 3. The composite structure was B / A / B (composite ratio: 1: 10: 1), except that the polyester of the same composition as that used in the Example 1 in the polyester in the B layer was used. In the same manner, a 60 µm film was obtained. The obtained film was flexible at room temperature and was especially excellent in printability.

Example 5

The addition amount of the plasticizer used in Example 3 is 5% by weight, the particles used for the B layer are changed to agglomerated silica, and the composite structure is B / A / B (compound ratio: 1: 10: 1), In addition, the casting method was changed to a method of cooling and solidifying in a mirror-cooling drum (10 ° C) while applying electrostatic force. A non-oriented film was obtained in the same manner as in Example 2 except for this. The biaxially stretched film was obtained for the obtained unstretched film as longitudinal stretch temperature of 80 degreeC, longitudinal stretch magnification 3.1 times, horizontal stretch temperature 100 degreeC, horizontal stretch magnification 2.8 time, and heat processing temperature 230 degreeC. Although the moldability of the film fell, it was excellent in printability.

Example 6

100 탆 unstretched film in the same manner as in Example 2 except that polyester and stearyl phosphate were mixed so as to have the composition shown in Table 3, and the casting method was electrostatically applied and cooled and solidified in a 10 ° C. mirror cooling drum. Got.

Example 7

In Example 1, an unoriented film of 100 µm was obtained in the same manner as in Example 1 except that PPT / I ¹⁰ was used instead of PPT. In particular, moldability became favorable.

Example 8

The unstretched film was obtained like Example 6 except having mixed polyester and stearyl phosphoric acid so that it may become a composition of Table 4, and using 10 weight% of plasticizers used in Example 3. The biaxially stretched film was obtained by making the obtained unstretched film 75 degreeC of longitudinal stretch, 3.0 times longitudinal stretch magnification, 85 degreeC of lateral stretch temperature, 2.8 times lateral stretch magnification, and 160 degreeC of heat processing temperature. Although the printability fell in the characteristic of the obtained film compared with the film obtained in Example 5, the flexibility in room temperature became favorable.

Example 9

The polyester was changed to the composition shown in Table 4, the composite composition was B / A / B (composite ratio: 1: 10: 1), and the solidification was performed by cooling and solidifying in a mirror-cooling drum (10 ° C) while electrostatically applying the casting method. A non-oriented film of 100 µm was obtained in the same manner as in Example 2 except for using the method. The film obtained by laminating polyester B was excellent in solvent resistance and excellent in printability.

Example 10

The polyester and stearyl phosphate are mixed so as to have the composition shown in Table 5, the composite composition is B / A / B (compound ratio: 1: 10: 1), and the mirror type cooling drum (10 ° C) while electrostatically applying the casting method. 100 micrometers of unstretched film were obtained by the same method as Example 2 except having carried out the cooling-solidification process at. Although it is inferior to printability slightly compared with Example 9, moldability and workability were equally favorable.

(Comparative Example 1)

PET (1) and particle-containing PET were mixed so as to have the composition shown in Table 5, and film production was carried out in the same manner as in Example 2. As a result, thermal workability, such as embossability, fell significantly.                 

(Comparative Example 2)

Using PET / CHDM ³⁰ (particle-added PET / CHDM ³⁰ was used separately), an unoriented film having a thickness of 60 μm was obtained in the same manner as in Example 1. It was an amorphous polyester film having no melting peak at crystal melting temperature curvature and very poor in solvent resistance. As a result, as shown in Table 5, printability fell significantly.

(Comparative Example 3)

A film was produced in the same manner as in Example 1 except that the polyester and the ataryl phosphoric acid were mixed so as to have the composition shown in Table 6 and the extruder temperature was set to 270 ° C. The resulting film showed PET and PBT with their respective melting points, ie, did not substantially become a single peak. The characteristic of the obtained film was inferior to whitening resistance, pressure-forming formation, embossing workability, and the like.

(Comparative Example 4)

Polyester was mixed so that it may become a composition of Table 6, and film forming was performed according to the method of Example 2 except for it. The obtained film was especially inferior in thermal stability and printability.

(Comparative Example 5)

Polyester was used as the composition of Table 6, and PPT and PBT were mixed, except film | membrane was produced according to the method of Example 2. Melting | fusing point of polyester A was 230 degrees C or less, and was inferior to heat stability, whitening resistance, and printability.                 

Example 1 Example 2 Example 3   Polyester steer A (floor A) Polymer type PET (1), PPT PET (2), PPT PET (2), PPT Acid component (mol%) Glycol component (mol%) TPA100 EG78, DEG2, PG20 TPA100 EG58, DEG2, PG40 TPA100 EG78, DEG2, PG20 Catalytic Metal / M (mmol%) P (mmol%) M / P (-) Ti, Mn, Sb / 58 80 0.74 Ti, Mn, Sb / 48 580 0.08 Ti, Mn, Sb / 58 580 0.10 Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (㎛) Particle Addition (wt%) Plasticizer Addition (wt%) 247 0.74 Crosslinked Polystyrene 6.0 0.5- 251 0.76 Silicon 5.0 0.3- 250 0.71 Crosslinked Polystyrene 6.0 0.4 5   Polyester steer B (B floor) Polymer type - - - Acid glycol -- -- -- Catalytic Metal / M (mmol%) P (mmol%) M / P (-) --- --- --- Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (㎛) Particle Addition (wt%) ----- ----- ----- Lamination Structure Average Break Elongation at 80 ℃ (%) Planar Orientation Coefficient (-) Thermal Stability Whitening Resistance Compression Resistance Formability Printability Embossability Fault 920 0 O O ◎ O O Fault 890 0 ◎ O ◎ O O Fault 1100 0 ◎ O ◎ O ◎

Example 4 Example 5 Example 6   Polyester steer A (floor A) Polymer type PET (2), PPT PET (2), PPT PET (2), PBT Acid component (mol%) Glycol component (mol%) TPA100 EG78, DEG2, PG20 TPA100 EG78, DEG2, PG20 TPA100 EG83, DEG2, BG15 Catalytic Metal / M (mmol%) P (mmol%) M / P (-) Ti, Mn, Sb / 58 580 0.10 Ti, Mn, Sb / 58 580 0.10 Ti, Mn, Sb / 66 100 0.58 Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (µm) Particle Addition (wt%) Plasticizer Addition (wt%) 250 0.71---10 250 0.72---5 249 0.72 Crosslinked Polystyrene 6.0 0.5-   Polyester steer B (B floor) Polymer type PET (1), PPT PET (1), PPT - Acid glycol TPA100 EG78, DEG2, PG20 TPA100 EG78, DEG2, PG20 -- Catalytic Metal / M (mmol%) P (mmol%) M / P (-) Ti, Mn, Sb / 58 80 0.73 Ti, Mn, Sb / 58 80 0.73 --- Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (㎛) Particle Addition (wt%) 247 0.74 Crosslinked Polystyrene 6.0 0.5 247 0.74 Agglomerated silica 1.7 0.1 ----- Lamination Structure Average Break Elongation at 80 ℃ (%) Planar Orientation Coefficient (-) Thermal Stability Whitening Resistance Compression Resistance Formability Printability Embossability Composite (B / A / B) 1200 0-△ ◎ ◎ ◎ Composite (B / A / B) 410 0.09-◎ O ◎ O Fault 900 0 O △ ◎ O ◎

Example 7 Example 8 Example 9   Polyester steer A (floor A) Polymer type PET (1), PPT / I ¹⁰ PET (2), PBT PET (2), PPT Acid component (mol%) Glycol component (mol%) TPA98, IPA2 EG78, DEG2, PG20 TPA100 EG68, DEG2, BG30 TPA100 EG78, DEG2, PG20 Catalytic Metal / M (mmol%) P (mmol%) M / P (-) Ti, Mn, Sb / 58 60 0.92 Ti, Mn, Sb / 62 580 0.11 Ti, Mn, Sb / 58 580 0.10 Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (µm) Particle Addition (wt%) Plasticizer Addition (wt%) 251 0.68 Crosslinked Polystyrene 6.0 0.5- 249 0.72 Agglomerated silica 1.7 0.1 10 250 0.72----   Polyester steer B (B floor) Polymer type - - PET (1), PIB Acid glycol -- -- IPA45, TPA55 EG90, DEG2, BHEB8 Catalytic Metal / M (mmol%) P (mmol%) M / P (-) --- --- Ti, Mn, Sb / 55 60 0.92 Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (㎛) Particle Addition (wt%) ----- ----- 240 0.75 Crosslinked polystyrene 6.0 0.5 Lamination Structure Average Break Elongation at 80 ℃ (%) Planar Orientation Coefficient (-) Thermal Stability Whitening Resistance Compression Resistance Formability Printability Embossability Fault 1120 0 O ◎ ◎ O ◎ Single Layer 430 0.09 ◎ ◎ O O O O Compound (B / A / B) 950 0-◎ ◎ ◎ ◎

Example 10 Comparative Example 1 Comparative Example 2   Polyester steer A (floor A) Polymer type PET (2), PPT PET (1) PET / CHDM30 Acid component (mol%) Glycol component (mol%) TPA100 EG78, DEG2, PG20 TPA100 EG98, DEG2 TPA100 EG70, CHDM30 Catalytic Metal / M (mmol%) P (mmol%) M / P (-) Ti, Mn, Sb / 58 580 0.10 Mn, Sb / 70 100 0.70 Mn, Co 80 80 1.00 Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (µm) Particle Addition (wt%) Plasticizer Addition (wt%) 250 0.72---- 254 0.69 Agglomerated silica 1.7 0.2- 0.72 Silicon 5.0 0.25   Polyester steer B (B floor) Polymer type PET (1), PET / CHDM ³⁰ - - Acid glycol TPA100 EG78, DEG2, CHDM15 -- -- Catalytic Metal / M (mmol%) P (mmol%) M / P (-) Ti, Mn, Sb / 75 90 0.83 --- --- Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (㎛) Particle Addition (wt%) 247 0.74 Crosslinked Polystyrene 6.0 0.5 ----- ----- Lamination Structure Average Break Elongation at 80 ℃ (%) Planar Orientation Coefficient (-) Thermal Stability Whitening Resistance Compression Resistance Formability Printability Embossability Composite (B / A / B) 1100 0-◎ ◎ O ◎ Fault 840 0 ◎ O △ O × Fault 930 0-◎ △ × △

Comparative Example 3 Comparative Example 4 Comparative Example 5   Polyester steer A (floor A) Polymer type PET (1), PBT PET (2), PPT PPT, PBT Acid component (mol%) Glycol component (mol%) TPA100 EG48, DEG2, BG50 TPA100 EG78, DEG2, PG20 TPA100 BG80, PG20 Catalytic Metal / M (mmol%) P (mmol%) M / P (-) Ti, Mn, Sb / 58 580 0.10 Ti, Mn, Sb / 58 16 3.63 Ti / 43 25 1.72 Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (µm) Particle Addition (wt%) Plasticizer Addition (wt%) 226,252 0.74 Crosslinked Polystyrene 6.0 0.4- 243 0.72 Crosslinked Polystyrene 6.0 0.5- 220 0.85 Crosslinked polystyrene 6.0 0.5-   Polyester steer B (B floor) Polymer type - - - Acid glycol -- -- -- Catalytic Metal / M (mmol%) P (mmol%) M / P (-) --- --- --- Melting Peak Temperature (℃) Intrinsic Viscosity Particle Average Particle Diameter (㎛) Particle Addition (wt%) ----- ----- ----- Lamination Structure Average Break Elongation at 80 ℃ (%) Planar Orientation Coefficient (-) Thermal Stability Whitening Resistance Compression Resistance Formability Printability Embossability Fault 750 0-× × O × Fault 950 0 × O O × O Fault 900 0 × × O × O

In addition, the symbol in a table | surface is as follows.

PET (1): Phosphorus Highly Added Polyethylene Terephthalate

PET (2): Normally polyethylene terephthalate

PPT: Polypropylene Terephthalate

PPT / I ¹⁰ : 10 moles of isophthalic acid copolymerized PPT

PBT: Polybutylene Terephthalate

PET / CHDM ³⁰ : Cyclohexanedimethanol 30 mol copolymer PET

PIB: Isophthalic Acid Copolymer

EG: ethylene glycol

PG: propanediol (1,3-propanediol)

DEG: Diethylene Glycol

BG: butanediol (1,4-butanediol)

Since the polyester film of this invention is excellent in moldability, workability, and printability, especially in industrial material use, packaging material use, and construction material use, in the case of shaping | molding, processing, a printed product, or shaping | molding, processing, and printing, It can be used preferably as a process film.

Claims (6)

Polyester A comprising two or more glycol components selected from ethylene glycol, butanediol and propanediol as constituents, and the crystal melting temperature curve of polyester A in the DSC temperature measurement has a substantially single peak. The melt peak temperature is 230 degreeC or more, and satisfy | fills following formula (1), The polyester film characterized by the above-mentioned. M / P≤1 ‥‥‥ (1) (Wherein M represents a concentration of the catalytic metal element remaining in polyester A (millimolar%), and P represents the amount of phosphorus remaining in polyester A (millimolar%). The polyester film according to claim 1, wherein the polyester A contains 20 to 1000 mmol% of phosphorus compound as a small amount of phosphorus. The polyester film according to claim 2, wherein the phosphorus compound has a molecular weight of 300 or more. The polyester film according to any one of claims 1 to 3, wherein the polyester A is composed of 40 to 90 mol% of polyethylene terephthalate and 10 to 60 mol% of polypropylene terephthalate. The polyester film according to any one of claims 1 to 3, wherein the polyester A contains 1 to 60% by weight of a plasticizer having a molecular weight of 3000 or less. Polyester B is laminated | stacked on the at least single side | surface of the polyester film in any one of Claims 1-3, The laminated polyester film characterized by the above-mentioned.