JP2000345013A - Polyester resin for forming - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition showing excellent laminating ability, impact resistance and a taste characteristic by mixing a non-crystalline or low crystalline polyester B with a crystalline polyester A, the weight ratio being specific, to give a polyester resin having a carboxy end group of not less than a specific amount. SOLUTION: A polyester resin M having not less than 25 equivalents/ton of a carboxy end group is obtained by mixing a non-crystalline or low crystalline polyester B with a crystalline polyester A, the weight ratio of A to B being 9/1 to 1/9. A polyester resin N made of a crystalline polyester C having a melting point of 245 to 280 deg.C is disposed at least on one side of the polyester resin M to give a laminated item. The crystalline polyester A is polyethylene terephthalate or the like or a copolymer thereof having a low copolymerization degree of not more than 15 mole % and a melting point of 200 to 280 deg.C. The non-crystalline polyester B is a polyester such as polyethylene terephthalate or the like which does not crystallize and contains a polymer having a copolymerization degree of not less than 25 mol%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polyester resin for molding. In detail, it is not only excellent in moldability, impact resistance and storage stability when used as a packaging material, but also for laminate molding applications, especially for laminate molding applications used by laminating to metal plates by extrusion lamination, containers It relates to a suitable polyester resin for molding.

[0002]

2. Description of the Related Art In recent years, as packaging materials have been diversified and evolved, applications in which polyester and its contents have come into direct contact have increased, and with the increase in shelf life, the quality of polyester resins, especially moldability and impact resistance. It has been considered to improve the characteristics such as.

In the case of using a polyester resin for the inner surface of a container, which has been increasing in recent years, among packaging materials, for example, a metal and a polyester film are laminated with or without an adhesive and molded. Go and get the container.

Conventionally, the inner surface and outer surface of a metal can are coated with various thermosetting resins, such as epoxy and phenol, dissolved or dispersed in a coating material to prevent corrosion. Has been widely practiced. However, such a coating method using a thermosetting resin requires a long time to dry the paint, and the productivity is reduced,
There are unfavorable problems such as environmental pollution due to a large amount of organic solvents.

As a method for solving these problems, a method of extruding and laminating a polymer on a steel plate, an aluminum plate or a metal plate on which various surface treatments such as plating are applied to the metal plate, a method of laminating the polymer with a sheet And then laminating it on a metal plate after biaxial stretching. When a metal plate laminated with these polymers is drawn or ironed, the following characteristics are required for the polymer laminated metal plate.

(1) Lamination to a metal plate is easy and excellent in adhesion. (2) It is excellent in moldability and does not generate defects such as pinholes after molding. (3) The polymer does not peel off from the metal plate, and cracks, pinholes, etc. do not occur due to impact on the metal can. (4) The scent component of the contents of the can adsorbs to the polymer,
The flavor of the contents is not impaired by the odor of components eluted from the polymer (hereinafter referred to as taste characteristics).

Many proposals have been made to satisfy these requirements. For example, Japanese Patent No. 2852690 discloses a resin which is extruded and laminated on a tin-plated steel sheet. Discloses polyester used for extrusion lamination. Further, JP-A-10-138315 and JP-A-10-138316 disclose a method of manufacturing a laminate material by extrusion lamination. However, these proposals do not comprehensively satisfy the various requirements as described above, and are particularly satisfactory in terms of achieving both lamination properties on metal plates and lamination and impact resistance after molding. I couldn't say it was at a level I could do.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and it is not only possible to cope with severe molding such as drawing or ironing as a molding resin, but also to solve the problem. An object of the present invention is to provide a polyester resin for molding which is excellent in laminating property, adhesion, impact resistance and taste characteristics to a material.

[0009]

In order to solve the above-mentioned problems, a polyester resin for molding according to the present invention comprises a crystalline polyester A and an amorphous or low-crystalline polyester B in a weight ratio of 9: 1 to 1: 1. The polyester resin (I) is mixed at a ratio of 9 and has a carboxyl end group content of 25 equivalents / ton or more.

The polyester resin for molding according to the present invention may have a form in which a polyester resin (II) comprising a crystalline polyester C is disposed on at least one surface of the polyester resin (I).

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with preferred embodiments. The polyester constituting the polyester resin of the present invention is a general term for polymers having a main bond in the main chain as an ester bond, and can be usually obtained by a polycondensation reaction between a dicarboxylic acid component and a glycol component. Here, as the dicarboxylic acid component, for example, terephthalic acid, naphthalenedicarboxylic acid, isophthalic acid, diphenyldicarboxylic acid, diphenylsulfondicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sodiumsulfondicarboxylic acid, aromatic dicarboxylic acids such as phthalic acid, Examples thereof include aliphatic dicarboxylic acids such as oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, and fumaric acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and paraoxybenzoic acid. As the glycol component, for example, ethylene glycol, propanediol,
Aliphatic glycols such as butanediol, pentanediol, hexanediol and neopentyl glycol;
Examples thereof include polyoxyalkylene glycols such as diethylene glycol, polyethylene glycol, and polypropylene glycol, alicyclic glycols such as cyclohexanedimethanol, and aromatic glycols such as bisphenol A, bisphenol S, and resorcin ethylene oxide adduct.

The crystalline polyester in the present invention is:
Polyester which exhibits an endothermic peak accompanying melting in a differential scanning calorimeter, and examples thereof include polyethylene terephthalate, polyethylene 2,6-naphthalenedicarboxylate and low-rate copolymers thereof.
The copolymerization component can be arbitrarily selected from, for example, the dicarboxylic acid component and the glycol component,
The copolymerization ratio is preferably 15 mol% or less. The crystalline polyester A has a melting point of 200 to 2 among these.
A temperature of 80 ° C. is preferable from the viewpoint of impact resistance, heat resistance and taste characteristics. If the melting point is lower than 200 ° C., the crystallinity becomes poor, which is not preferable. If the melting point exceeds 280 ° C., it is not preferable from the viewpoint of productivity. In addition, from a viewpoint of heat resistance and taste characteristics, the melting point is more preferably 220 to 280 ° C, and the melting point is more preferably 245 to 280 ° C because the taste characteristics are further improved. Further, the crystalline polyester C preferably has a melting point of 245 to 280 ° C. from the viewpoint of taste characteristics. Further crystalline polyester A
It is preferable that C and C have the same composition because cracking due to peeling, displacement, and stress concentration at the lamination interface does not occur.

The non-crystalline or low-crystalline polyester of the present invention includes, for example, polyesters that do not crystallize or polyesters with a very low crystallization rate, such as polyethylene terephthalate and high-copolymers of polyethylene 2,6-naphthalenedicarboxylate. In the differential scanning calorimeter, the endothermic peak accompanying melting does not appear, or even if it does, the heat of fusion is 20 J
/ G of polyester. Here, the high-rate copolymerization includes a copolymer component of 25 mol% or more. Further, even a polyester comprising a single dicarboxylic acid component and a glycol component is not particularly limited as long as it does not crystallize or has a sufficiently low crystallization rate. For example, polyethylene isophthalate is exemplified. Can be. Among the amorphous or low-crystalline polyester B of the present invention,
A copolymerized polyester is preferred, and a copolymer of polyethylene terephthalate or polyethylene 2,6-naphthalenedicarboxylate is particularly preferred. Also,
The copolymerization component is not particularly limited, but as the dicarboxylic acid component, terephthalic acid, naphthalenedicarboxylic acid, isophthalic acid, adipic acid, sebacic acid, and the like can be preferably used, and as the glycol component, neopentyl glycol, Cyclohexane dimethanol, resorcin ethylene oxide adduct, and the like can be preferably used. Among these, it is particularly preferable to copolymerize cyclohexanedimethanol and resorcin ethylene oxide adduct. Further, two or more copolymer components may be used in combination.

The polyester resin of the present invention is made of crystalline polyester A from the viewpoint of moldability and impact resistance after molding.
And an amorphous or low-crystalline polyester B in a weight ratio of 9: 1.
Polyester resin (I) mixed at a ratio of ~ 1: 9
It is necessary to consist of The method of mixing is not particularly limited, but a method of dry-blending the pellets of polyester A and polyester B at a predetermined weight ratio during melt-extrusion and feeding the mixture into an extruder, or a method using a melt-extruder in advance. A method using a blended and pelletized material is preferably used. If the mixing ratio is out of the range, no improvement in moldability and improvement in impact resistance, which are considered to be caused by mixing, are observed. Also,
Even when the composition of polyester A and polyester B is copolymerized in advance, no improvement in impact resistance is observed. This is because, by mixing the crystalline polyester A and the amorphous or low-crystalline polyester B, a sea-island structure is formed in the polyester resin (I), and this sea-island structure is improved in moldability and impact resistance after molding. It is considered to have contributed.

The polyester resin (I) of the present invention must have a carboxyl terminal group content of 25 equivalents / ton or more from the viewpoint of adhesion and moldability when laminated with a substrate. When the amount of the carboxyl terminal group is less than 25 equivalents / ton, the adhesion to a substrate, particularly a metal plate is poor, and peeling may occur during molding. The amount of the carboxyl terminal group is preferably 30 equivalents / ton or more from the viewpoint of adhesiveness, and more preferably 35 equivalents / ton or more because the adhesiveness is further improved. On the other hand, if the amount of the carboxyl terminal group exceeds 45 equivalents / ton, no improvement in adhesion is observed, and conversely, heat resistance and taste characteristics may deteriorate, which is not preferable. The method for adjusting the amount of the carboxyl terminal group to 25 equivalents / ton or more is not particularly limited, but a method for adjusting the polymerization temperature and the polymerization time is simple and preferable. Also,
Particularly, polyester A constituting polyester resin (I)
Is preferably 25 equivalents / ton or more.

The polyester resin of the present invention preferably has a polyester resin (II) comprising a crystalline polyester C disposed on at least one surface of the polyester resin (I) from the viewpoint of impact resistance and taste characteristics. The method for arranging the crystalline polyester C on at least one surface of the polyester resin (I) is not particularly limited.
For example, a method is preferably used in which the polyester resin (I) and the polyester resin (II) are respectively charged into separate melt extruders, laminated at a feed block portion provided above the T die, and discharged from the die.

In the present invention, the amount of the diethylene glycol component in the polyester resin (I) is preferably 3 mol% or less from the viewpoint of impact resistance and taste characteristics. If the amount of the diethylene glycol component exceeds 3 mol%, the polyester may deteriorate due to heat history during molding, which is not preferable. Further, since diethylene glycol is generally produced as a by-product during the production of polyester, it is not preferable to reduce the amount of the component to less than 0.01 mol% since the polymerization step becomes complicated and leads to an increase in cost. Further, from the viewpoint of taste characteristics, the amount of the diethylene glycol component is more preferably 2.5 mol% or less.

In producing the polyester of the present invention, conventionally known reaction catalysts and coloring inhibitors can be used. Examples of the reaction catalyst include an alkali metal compound,
Alkaline earth metal compounds, zinc compounds, lead compounds, manganese compounds, cobalt compounds, aluminum compounds, antimony compounds, titanium compounds, and the like, examples of the coloring inhibitor include phosphorus compounds,
It is not particularly limited to these. Usually at any stage before the completion of the production of polyester, antimony compound or germanium compound as a polymerization catalyst,
It is preferable to add a titanium compound. For example, taking a germanium compound as an example of such a method,
Examples include a method of adding a germanium compound powder as it is, and a method of adding a germanium compound dissolved in a glycol component which is a starting material of a polyester, as described in JP-B-54-22234. it can.

Examples of the germanium compound include germanium dioxide, germanium hydroxide hydrate, and germanium alkoxide compounds such as germanium tetramethoxide, germanium tetraethoxide, germanium tetrabutoxide, germanium ethylene glycolide, germanium phenolate, and the like. Examples include germanium phenoxide compounds such as germanium β-naphthalate, germanium phosphate compounds such as germanium phosphate and germanium phosphite, and germanium acetate. Among them, germanium dioxide is preferable. The antimony compound is not particularly limited, and examples thereof include oxides such as antimony trioxide, and antimony acetate. The titanium compound is not particularly limited, but alkyl titanates such as tetraethyl titanate and tetrabutyl titanate are preferably used.

For example, in the case of producing polyethylene terephthalate, when germanium dioxide is added as a germanium compound, a transesterification or esterification reaction between a terephthalic acid component and an ethylene glycol component is performed, and then a germanium dioxide and a phosphorus compound are added. Subsequently, a method of obtaining a germanium element-containing polymer by performing a polycondensation reaction at a high temperature and under a reduced pressure until a constant diethylene glycol content is obtained is preferably adopted. As a more preferable method, the obtained polymer is subjected to a solid-phase polymerization reaction under a reduced pressure or an inert gas atmosphere at a temperature equal to or lower than its melting point,
A method of reducing the content of acetaldehyde to obtain a predetermined intrinsic viscosity and a predetermined amount of a carboxyl terminal group is exemplified.

The polyester of the present invention may contain 0.01 to 10% by weight of inorganic and / or organic particles having an average particle size of 0.1 to 5 μm in order to improve processability. However, it is not preferable to use particles having an average particle diameter of more than 5 μm because defects are likely to occur in the polymer layer. In particular, since it is not preferable to include particles having a size of 30 μm or more, it is preferable to use a filter capable of sharply reducing foreign substances having a size of 30 μm or more as a filter at the time of extrusion. Examples of inorganic and / or organic particles include wet and dry silica, colloidal silica, titanium oxide, calcium carbonate, calcium phosphate,
Inorganic particles such as barium sulfate, alumina, mica, kaolin, clay and styrene, silicone, acrylic acid,
Organic particles containing divinylbenzene as a component can be exemplified. Two or more of these inorganic particles and / or organic particles may be used in combination.

Further, in producing the polyester resin of the present invention, additives such as a plasticizer, an antistatic agent, a weathering agent and the like can be used as needed.

The polyester resin of the present invention is preferably formed by laminating the polyester resin on a base material, and the laminating method is a method of biaxially stretching the polyester resin according to a known method, forming the film into a film, and then laminating the polyester resin. A method of melt extrusion lamination on a substrate is preferred, and a method of melt extrusion lamination is particularly preferred. Further, a metal plate is preferable as a substrate to be laminated. The method of melt extrusion lamination is not particularly limited, but an example of a method of producing a melt extrusion laminate on a metal plate will be described below.

As crystalline polyester A, polyethylene terephthalate, amorphous or low crystalline polyester B
When using 30 mol% of copolymerized polyethylene terephthalate as cyclohexane dimethanol, the raw material pellets of polyester A and polyester B are uniformly mixed at a weight ratio of 1: 1 and then supplied to a twin-screw vent type extruder. And melt. At this time, the temperature of the extruder is preferably set at 275 to 285 ° C. The polyester resin (I) obtained by mixing the polyester A and the polyester B thus melt-mixed is directly extruded from a die onto a metal plate and laminated. Then, it is quenched in a water bath and solidified by cooling. Further, in the laminating step, it is preferable to perform a dustproof treatment since defects of the polymer hardly occur.

The resin thickness of the extrusion laminate is preferably from 7 to 30 μm from the viewpoint of moldability and impact resistance, and more preferably from 12 to 30 μm from the viewpoint of moldability. When the polyester C is disposed on one side of the polyester resin (I), the lamination ratio is preferably 1:10 to 1: 1 from the viewpoint of impact resistance.

When the polyester resin of the present invention is biaxially stretched and then laminated on a substrate, the thickness of the biaxially stretched polyester film is preferably from 5 to 30 μm from the viewpoint of coatability, moldability and impact resistance. From the viewpoint of productivity, the thickness is more preferably 10 to 30 μm.

The laminate substrate of the present invention is not particularly limited, but is preferably a metal plate. As the metal plate, a steel plate or an aluminum plate is preferable in terms of formability.
Furthermore, in the case of a steel sheet, the surface of the steel sheet is treated with an inorganic oxide film layer for improving adhesion and corrosion resistance, for example, chromic acid treatment, phosphoric acid treatment, chromic acid / phosphoric acid treatment, electrolytic chromic acid treatment, chromate treatment, chromium chromate treatment, etc. A typical chemical conversion coating layer may be provided. In particular, chromium hydrated oxide of 6.5 to 150 mg / m ² is preferable as chromium in terms of metal chromium, and even if a spreadable metal plating layer such as nickel, tin, zinc, aluminum, gunmetal, or brass is provided. Good. 0.5 to 15 g / m for tin plating
² , 1.8 to 20 g for nickel or aluminum
/ M ² is preferable.

The polyester resin for molding of the present invention can be suitably used for coating the inner and outer surfaces of a two-piece metal can produced by drawing or ironing.
Further, it can be preferably used for covering the lid portion of a two-piece can or the body, lid, and bottom of a three-piece can because it has good moldability and impact resistance.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments. The characteristics were measured and evaluated by the following methods.

(1) Melting Point (Tm) of Polyester About 5 mg of pellets were crystallized and measured by a differential scanning calorimeter (DSC2, manufactured by Perkin-Elmer Co.) at a heating rate of 20 ° C./min. The temperature was taken as the melting point (Tm).

(2) Carboxyl terminal group content The polyester resin (I) was dissolved in ortho-cresol / chloroform (weight ratio: 7/3) at 90 to 100 ° C for 20 minutes and subjected to potentiometric titration with an alkali. unit:
Equivalent / ton). When the polyester resin (II) was arranged on one side of the polyester resin (I), only the polyester resin (I) was scraped off and subjected to the measurement.

(3) Diethylene glycol content Measured by nuclear magnetic resonance spectroscopy ( ^13C -NMR spectrum).

(4) Adhesiveness A metal plate coated with a polyester resin was ironed as in the following example, and an ironing machine (forming ratio (maximum thickness / minimum thickness) = 3.
0) to obtain a metal can. The metal can was baked at 200 ° C. for 15 minutes and then retorted at 125 ° C. for 30 minutes. The state of the inner surface of the can after the retort treatment was evaluated as follows. Class A: No rust was observed at all. Class B: No rust was observed, but cracks were observed in the coating resin. Class C: Rust was generated.

(5) Impact Resistance A metal can made in the same manner as described above is filled with water and has a height of 1.0
m was dropped on a vinyl chloride tile floor. afterwards,
A voltage of 6 V was applied to the electrode and the metal can in water, and the current value after 3 seconds was read, and 10 cans were measured and averaged. Class A: less than 0.001 mA Class B: 0.001 to 0.01 mA Class C: 0.01 mA or more

(6) Taste characteristics A perfume aqueous solution (d-limonene 25 ppm aqueous solution) was placed in a metal can made in the same manner as described above, allowed to stand at room temperature for 4 weeks after sealing, and then opened to detect changes in odor by a sensory test. Evaluation was made according to the following criteria. A: no change in odor B: no change in odor C: change in odor

Examples 1 to 5, Comparative Examples 1 to 4 In Example 1, polyethylene terephthalate (melting point: 255 ° C.) was used as crystalline polyester A, and cyclohexane dimethanol 3 was used as amorphous or low crystalline polyester B.
Using 0 mol% copolymerized polyethylene terephthalate, the mixture was dry-blended in the form of pellets at a weight ratio of 7: 3, and supplied to a twin-screw vented extruder (temperature: 280 ° C). After once casting the mixed polyester resin from a die onto a cooling roll, the mixture was extruded onto a 0.25 mm-thick steel plate (tin-free steel: TFS) so as to have a thickness of 30 μm (lamination speed: 80 m / min), Immediately cooled in a water bath. The polyester resin (I) had a carboxyl terminal group content of 35 equivalents / ton and a diethylene glycol content of 2.6 mol%. The polyester resin laminated steel sheet thus obtained was used for evaluation.

In Example 2, the mixing ratio of the polyester resin (I) of Example 1 was changed to polyester A: polyester B =
5: 5 and separately as crystalline polyester C
Using the same polyethylene terephthalate (melting point: 255 ° C.) as polyester A, and vacuum drying at 180 ° C., polyester C was supplied to an extruder (temperature: 282 ° C.) different from the extruder of Example 1, and After laminating with the polyester resin (I) by the feed block installed on the upper part, it was discharged from the die and extruded and laminated in the same manner as in Example 1 so that the polyester resin (I) was in contact with the steel plate side. At this time, the lamination ratio of the polyester resin (I) and the polyester resin (II) was 1: 3, and the thickness of the resin layer was 30.
μm. The amount of carboxyl terminal groups in the polyester resin (I) was 37 equivalents / ton, and the content of diethylene glycol was 2.7 mol%.

In Example 3, 6 mol% isophthalic acid copolymerized polyethylene terephthalate (melting point: 241 ° C.) was used as crystalline polyester A, and 28 mol% neopentyl glycol copolymerized polyethylene terephthalate was used as amorphous or low crystalline polyester B. , And then supplied to a twin-screw vented extruder (temperature: 275 ° C.). After discharging from the die, extrusion lamination was performed in the same manner as in Example 1 (resin thickness 25 μm). The carboxyl terminal group amount of the polyester resin was 28 equivalents / ton, and the diethylene glycol component amount was 3.4 mol%.

In Example 4, the polyester resin (I) obtained by blending the crystalline polyester A of Example 3 with the B resin (manufactured by Mitsui Chemicals, Inc.) as the amorphous or low-crystalline polyester B in a ratio of 5: 5 was used. As polyester C, 10 mol% of naphthalenedicarboxylic acid copolymerized polyethylene terephthalate (melting point: 234 ° C.) was laminated in the same manner as in Example 2 (laminating ratio 1: 4), and then extrusion-laminated with a thickness of 25 μm. The amount of the carboxyl terminal group in the polyester resin (I) was 42 equivalents / ton, and the amount of the diethylene glycol component was 3.3 mol%.

In Example 5, as polyester A, polyethylene terephthalate (melting point: 256 ° C.) and polyester B, cyclohexane dimethanol 30 mol% copolymerized polyethylene terephthalate, were dry-blended at a weight ratio of 4: 6. The mixture was supplied to an extruder and discharged into water to obtain a gut, which was then cut to obtain a blend chip of the polyester resin (I). The chips and polyethylene terephthalate (melting point: 255 ° C.) used as polyester C were each dried by a vacuum dryer, then supplied to separate extruders, laminated by a feed block placed above the die, and placed on a cooling drum from the die. Extruded to obtain a cast film. Thereafter, the cast film is successively biaxially stretched to obtain a biaxially stretched film (film thickness 2).
0 μm). At that time, the stretching conditions were a longitudinal stretching temperature of 105 ° C, a magnification of 3.0 times, a transverse stretching temperature of 120 ° C, and a magnification of 2.9 times, and the heat treatment was performed at a relaxation rate of 5% and 190 ° C. The biaxially stretched film thus obtained is
TFS steel plate (plate thickness 0.22
mm) so that the polyester resin (I) layer side is closely adhered thereto, and then rapidly cooled in a water bath. The amount of carboxyl terminal groups in the polyester resin (I) layer of the biaxially stretched film is 40 equivalents / ton, and the amount of diethylene glycol component is 1.
9 mol%.

In Comparative Example 1, polyethylene terephthalate (melting point: 254 ° C.) was used alone as the polyester resin (I), and extrusion lamination was performed on a TFS steel sheet in the same manner as in Example 1. The amount of carboxyl terminal group and the amount of diethylene glycol component are 31 equivalents / ton and 2.8 mol%, respectively.
Met.

Comparative Example 2 was the same as Example 1 except that a polyester resin (I) blended with polyethylene terephthalate and 33 mol% of cyclohexanedimethanol copolymerized polyethylene terephthalate in a weight ratio of 0.5: 9.5 was used. Extrusion lamination was carried out. The amount of carboxyl end groups was 37 equivalents / ton, and the amount of diethylene glycol component was 4.1 mol%.

In Comparative Example 3, polyethylene terephthalate (melting point: 255 ° C., carboxyl end group content: 19 equivalents / ton) was used as polyester A, and polyethylene isophthalate (carboxyl end group amount: 21 equivalents / ton) was used as polyester B. Example 1 except that the one blended in the composition No. 5 was used as the polyester resin (I).
Extrusion lamination was carried out on a TFS steel sheet in the same manner as in the above.

In Comparative Example 4, 30% by mole of cyclohexanedimethanol copolymerized polyethylene terephthalate was used alone for the polyester resin (I), and polyethylene terephthalate (melting point: 255) was used for the polyester resin (II).
C.) and extrusion lamination was carried out in the same manner as in Example 2.

Table 1 shows the physical properties and evaluation results of each of the examples and comparative examples.
3 are shown. When the polyester laminated metal plate obtained as described above was evaluated, as shown in the table, the examples according to the present invention exhibited excellent characteristics, whereas the comparative examples exhibited poor characteristics.

The abbreviations in the table are as follows. PET: polyethylene terephthalate PET / CHDM ^* : cyclohexane dimethanol copolymerized polyethylene terephthalate (* indicates copolymerization ratio (mol%)) PET / NPG ^* : neopentyl glycol copolymerized polyethylene terephthalate (* indicates copolymerization ratio (mol%)) B resin: Copolymerized amorphous polyester manufactured by Mitsui Chemicals, Inc. PET / I ^* : Isophthalic acid copolymerized polyethylene terephthalate (* indicates copolymerization ratio (mol%)) PEI: Polyethylene isophthalate DEG: Diethylene glycol

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

[Table 3]

[0050]

As described above, according to the polyester resin for molding of the present invention, not only can it be used for severe molding such as drawing or ironing as the molding resin, but also the laminating property and adhesion to the substrate can be obtained. It has excellent properties, impact resistance and taste characteristics, and can be suitably used for metal cans and the like manufactured by molding.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masahiro Kimura 1-1-1, Sonoyama, Otsu-shi, Shiga F-term (reference) in the Shiga Plant of Toray Industries, Inc. 4F100 AB01C AB03 AK41A AK41B AK42 AL02A AL05A BA02 BA03 BA07 BA10A BA10C EH23C GB16 JA04A JA04B JA11A JA11B JA12A JK10 JL01 JL11 YY00A YY00B 4J002 CF03W CF03X CF06W CF06X CF08W CF08X GF00 GG01

Claims (8)

[Claims] 1. A polyester resin (I) obtained by mixing a crystalline polyester A with an amorphous or low-crystalline polyester B at a weight ratio of 9: 1 to 1: 9, and having a carboxyl terminal group content of 25. A polyester resin for molding characterized by having an equivalent weight / ton or more. 2. The polyester resin for molding according to claim 1, wherein the amount of the diethylene glycol component in the polyester resin (I) is 3 mol% or less. 3. The crystalline polyester A has a melting point of 200 to 200.
The polyester resin for molding according to claim 1 or 2, wherein the temperature is 280 ° C. 4. The polyester resin for molding according to claim 1, wherein the amorphous or low-crystalline polyester B is a copolymerized polyester. 5. The polyester resin for molding according to claim 1, wherein a polyester resin (II) comprising a crystalline polyester C is disposed on at least one surface of the polyester resin (I). 6. The crystalline polyester C has a melting point of from 246 to
The polyester resin for molding according to claim 5, which is at 280 ° C. 7. The polyester resin for molding according to claim 1, which is used by being laminated on a substrate by extrusion lamination. 8. The polyester resin for molding according to claim 1, which is used by being laminated on a metal plate.