JPH10231414A - Polyester resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester resin composition excellent in heat sealability, hydrogen peroxide resistance, flavor barrier properties, gas barrier properties and mechanical strengths and effective for e.g. a container for a drink containing a perfume component and to provide a molding thereof. SOLUTION: This invention provides a polyester resin composition prepared by melt-blending 100 pts.wt. polyethylene terephthalate resin containing 5-40mol%, based on the total structural units, naphthalenedicarboxylic acid units, 100-1,000ppm (in terms of the metal atoms) of a titanium compound, a manganese compound and/or a cobalt compound, an olefin polymer and a compatibilizer under conditions in which the relationships: 10<=X+Y<=100, 1<=X/Y<=90; and E/F<=1 [wherein E=η1 (X+Y)/(η2 X+η3 Y), F=100D2 D3 /D1 (D3 X+ D2 Y) (wherein X and Y are the contents (pts.wt.) of the olefin polymer and the compatibilizer per 100 pts.wt. polyester resin, respectively; η1 , η2 and η3 are their melt viscosities (P) at their respective melt mixing temperatures; and D1 , D2 and D3 are their densities at 25 deg.C)] and a molding made from this composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyester resin composition, a molded article, a packaging material, a laminate, and a container using the composition. More specifically, the present invention provides heat sealability, resistance to hydrogen peroxide, flavor barrier properties,
The present invention relates to a polyester resin composition having excellent mechanical properties such as elongation and strength, and a film formed therefrom.The molded product such as the polyester resin composition and the film of the present invention utilizes the above-mentioned properties to provide a fruit juice beverage. It can be effectively used for various uses including a packaging material for a beverage container containing an aroma component such as.

[0002]

2. Description of the Related Art The disposal of used plastic containers has become a major social problem, and in view of this, there has been an increasing demand for paper containers that can be incinerated and recycled relatively easily as compared with plastic containers. This is no exception in the field of beverage containers such as juice containers. For containers such as juice, paper containers whose inner surfaces are coated with a resin film are generally widely used. In that case, as the resin film to coat the inner surface of the paper container,
Olefin-based resins are generally used, but when a paper container whose inner surface is coated with an olefin-based resin is used for a beverage container containing an aroma component such as a fruit juice beverage, the aroma is lost or the taste is changed. Problem may occur.

[0003] Therefore, it has been proposed to coat a polyester resin laminate having a modified polyethylene terephthalate layer containing about 5 to 20 mol% of copolymerized units on the inner surface of a paper container in place of an olefin resin (Japanese Patent Application Laid-Open No. H11-157556). Kaihei 3
-133838). In this case, the fragrance and taste of the beverage or the like filled in the paper container can be kept to some extent due to the inherent properties of the polyester resin such as gas barrier properties and flavor barrier properties. However, the coating layer made of the above-mentioned modified polyester resin laminate swells or bubbles in the polyester resin laminate coating layer when subjected to a sterilization treatment with hydrogen peroxide widely used in a paper container manufacturing process. Or a problem such as peeling off from the paper base material is apt to occur, and accordingly, there is a disadvantage that the processability and the process passability during the production of the paper container become extremely poor. In addition, there is a problem that hydrogen peroxide contained in the swollen polyester resin laminate migrates into the contents filled in the paper container, which may cause deterioration in food quality and safety.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyester resin having good properties such as gas barrier properties and flavor barrier properties while maintaining good properties even when subjected to a sterilization treatment with hydrogen peroxide. Swelling, bubble formation,
Does not cause problems such as peeling from the base material, and has excellent heat sealability. It can be firmly and smoothly bonded and laminated to paper and other base materials, and has excellent mechanical properties such as elongation. It is to provide a polyester resin composition which can obtain a film or the like which is excellent in handleability. An object of the present invention is to provide a molded article such as a film made of the polyester resin composition and a packaging material.

[0005]

Means for Solving the Problems As a result of diligent studies conducted by the present inventors to achieve the above object, a polyethylene terephthalate resin obtained by copolymerizing naphthalenedicarboxylic acid,
Polyester resin composition containing a titanium compound, a manganese compound and / or a cobalt compound, an olefin polymer and a compatibilizer in a specific ratio and melt-mixing them so as to satisfy specific requirements And molded products such as films, etc., which have good gas barrier properties and flavor barrier properties inherent to polyester resins, and have few defects such as swelling due to hydrogen peroxide, generation of bubbles, and peeling from substrates. In addition, the polyester resin composition or the film made of the polyester resin composition or the film made of the polyester resin composition has excellent mechanical properties such as heat sealability and elongation. The present inventors have found that a packaging material, a container, and the like suitable for use in the present invention can be obtained, and have completed the present invention.

That is, the present invention relates to (i) (A) mainly comprising a diol unit mainly composed of an ethylene glycol unit and a dicarboxylic acid unit mainly composed of a terephthalic acid unit, and further comprising a naphthalenedicarboxylic acid unit in total moles of all structural units. (B) at least one metal compound selected from the group consisting of titanium compounds, manganese compounds and cobalt compounds; (C) an olefin polymer; and (D) A polyester resin composition comprising: (ii) 100 to 1000 ppm by weight of a metal compound in terms of a metal atom, and an olefin-based polymer and a compatibilizer based on 100 parts by weight of the polyester resin. Formula (1) and Formula (2): 10 ≦ X + Y ≦ 100 (1) 1 ≦ X / Y ≦ 90 (2) where X and Y are Re polyester resin 100
It represents the content (parts by weight) of the olefin polymer and the compatibilizer with respect to parts by weight. (Iii) E / F ≦ 1 (3) where E = η ₁ (X + Y) / (η ₂ X + η ₃ Y) F = 100D ₂ D ₃ / D ₁ (D ₃ X + D ₂ Y) wherein X and Y are as defined above, η ₁ ,
η ₂ and η ₃ represent the melt viscosities (poise) of the polyester resin, the olefin-based polymer and the compatibilizer at the melt mixing temperature at the time of preparing the polyester resin composition, respectively, and D ₁ , D ₂ and D ₃ are The respective densities at 25 ° C. of the polyester resin, polyolefin polymer and compatibilizer are shown. ] Is obtained by melt-mixing to satisfy the following conditions:

The present invention is a molded article, particularly a film, comprising the above polyester resin composition, and the film of the present invention is preferably used for foods. Furthermore, the present invention includes a packaging material using the above polyester resin composition, a laminate having the above polyester resin composition layer and a paper layer, and a paper container having an inner surface coated with the above polyester resin composition. I do.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The polyester resin which is a main component of the polyester resin composition of the present invention mainly comprises a diol unit mainly composed of an ethylene glycol unit and a dicarboxylic acid unit mainly composed of a terephthalic acid unit, and a naphthalenedicarboxylic acid unit, and a diol unit. It is contained in an amount of 5 to 40 mol% based on the total number of moles of all the structural units of the dicarboxylic acid unit. If the naphthalenedicarboxylic acid unit is less than 5 mol%, the heat sealing properties of the polyester resin composition will be poor, and the swelling during sterilization with hydrogen peroxide will be large. On the other hand, when the content of the naphthalenedicarboxylic acid unit in the polyester resin exceeds 40 mol%, the heat sealability also decreases. From the viewpoint of improving heat sealability and suppressing swelling during sterilization with hydrogen peroxide, the content of naphthalenedicarboxylic acid units in the polyester resin is preferably in the range of 7.5 to 35 mol%.

The polyester resin in the present invention may have a structural unit other than those described above as long as the properties such as heat sealing property, gas barrier property and flavor barrier property are not impaired. Such other structural units include:
For example, diethylene glycol, 1,4-butanediol, polyethylene glycol (preferably having a molecular weight of 400
Diol units derived from diols such as 1,4-cyclohexanedimethanol; aromatic dicarboxylic acids such as isophthalic acid, paraphenylenedicarboxylic acid, and sulfoisophthalic acid; succinic acid, glutaric acid;
Adipic acid, pimelic acid, suberic acid, a dicarboxylic acid unit derived from an aliphatic dicarboxylic acid such as sebacic acid or an ester-forming derivative thereof, and a polyester resin may be one of the other structural units described above or It can have two or more types. In general, the proportion of the other structural units described above in the polyester resin is based on the total number of moles of all the structural units of the polyester resin,
Preferably it is less than about 5 mol%.

The intrinsic viscosity of the polyester resin used in the present invention (measured at 30 ° C. in a mixed solvent of phenol / tetrachloroethane at an equal weight) is from 0.60 to 1.50 dl / min in view of film formability and film strength. It is preferably in the range of g.

The polyester resin composition of the present invention comprises a second
Contains at least one metal compound selected from the group consisting of titanium compounds, manganese compounds and cobalt compounds. Examples of the titanium compound include titanates such as tetraisopropyl, tetrabutyl titanate, and tetrastearyl titanate.Examples of the manganese compound include manganese formate, manganese acetate, manganese salts of fatty acids such as manganese propionate, manganese chloride, Manganese bromide, manganese iodide, manganese halides such as manganese fluoride, manganese sulfate, manganese sulfide, manganese oxide, manganese hydroxide, and the like.Examples of the cobalt compound include cobalt formate, cobalt acetate,
Cobalt salts of fatty acids such as cobalt propionate, cobalt halides such as cobalt chloride, cobalt bromide, cobalt iodide, and cobalt fluoride; cobalt sulfate, cobalt sulfide, cobalt oxide, and cobalt hydroxide. Among them, manganese acetate, manganese sulfate, tetraisopropyl titanate, cobalt acetate, and cobalt sulfate are preferred from the viewpoint of more effectively suppressing the swelling of the film during sterilization with hydrogen peroxide. The polyester resin composition of the present invention may contain only one kind of the above metal compounds, or may contain two or more kinds.

[0012] The content of the above-mentioned metal compound is 1 in terms of metal atoms per 100 parts by weight of the polyester resin.
It is in the range of 00 to 1000 ppm. The content is 10
If it is less than 0 ppm, the swelling at the time of sterilization with hydrogen peroxide tends to be large, and if it exceeds 1000 ppm, the polyester resin is decomposed when melt-molding the polyester resin composition, and the film strength is reduced. And other problems. From the viewpoint of suppressing swelling during sterilization with hydrogen peroxide and suppressing a decrease in film strength due to decomposition of the polyester resin at the time of melt molding, the total content of the metal compound is calculated as metal atoms with respect to 100 parts by weight of the polyester resin. It is preferably in the range of 150 to 800 ppm.

Further, the polyester resin composition of the present invention contains an olefin polymer as a third component.
As the olefin polymer, an ethylene polymer is preferably used from the viewpoints of film strength and elongation, suppression of swelling of the film during sterilization with hydrogen peroxide, and examples thereof include high-density polyethylene and low-density polyethylene. Examples include polyethylene, linear low-density polyethylene, and ethylene-vinyl acetate copolymer. Among them, high-density polyethylene is more preferably used from the viewpoint of suppressing film breakage during film formation. Although not limited, in the present invention, use of an olefin polymer having a melt flow rate (MFR) of about 1 to 3 g / 10 minutes suppresses neck-in during film formation. Preferred from the point.

[0014] The polyester resin composition of the present invention contains a compatibilizer as a fourth component. In the polyester resin composition, the compatibilizing agent finely disperses the dispersed phase composed of the olefin polymer in the polyester resin forming the matrix phase, and improves the interfacial adhesion between the polyester resin phase and the olefin polymer phase. Used for the purpose of improving. As the compatibilizer, a polymer substance having a structural part having an affinity for a polyester resin and a structural part having an affinity for an olefin-based polymer in a molecule is preferably used. A terminal hydroxyl group and / or a terminal carboxyl in a block copolymer or a graft copolymer having a polymer portion having an affinity for the olefin polymer and a polymer portion having an affinity for the olefin polymer in the molecule; A polymer substance having a group reactive with a group in the molecule and having a high affinity for the olefin polymer is preferably used.

Among them, as the compatibilizing agent, (a) an ethylene / (meth) acrylic acid copolymer, (b) a metal ion crosslinked structure (ionomer) of ethylene / (meth) acrylic acid copolymer, (C) a block copolymer composed of a styrene / ethylene / butadiene copolymer block having a carboxyl group or a derivative group thereof and a styrene-based polymer block; and (iv) an olefin polymer block having a carboxyl group or a derivative group thereof. Polymers such as block copolymers comprising styrene and styrene-based polymer blocks are particularly preferably used, and the polyester resin composition of the present invention contains one or more of these polymer compatibilizers. Can be.

The ethylene / (meth) acrylic acid copolymer (a) mentioned as the compatibilizer includes ethylene /
Acrylic acid copolymers are preferred. In this case, the amount of acrylic acid copolymerized is 4 to 15% by weight, because the mechanical properties of the polyester resin composition and the molded product obtained therefrom are improved, so that it is more preferable. preferable. When the copolymerization amount of acrylic acid is less than 4% by weight, it does not show sufficient affinity with both the polyester resin phase and the olefin-based polymer phase, and the mechanical properties such as the polyester resin composition and the molded article formed therefrom are not exhibited. It is likely that physical properties and the like are deteriorated. On the other hand, if the copolymerization amount of acrylic acid in the ethylene / acrylic acid copolymer exceeds 15% by weight, a gel-like substance may be generated in the polyester resin composition.

As the metal ion crosslinked structure (ionomer) of the ethylene / (meth) acrylic acid copolymer (b) mentioned above as the compatibilizer, sodium ion crosslinked ethylene / methacrylic acid copolymer can be used. A structure or a zinc ion cross-linked structure is preferably used. In this case, the copolymerization amount of methacrylic acid in the ionomer is 5 to 15% by weight, such as a polyester resin composition and a molded article obtained therefrom. It is preferable in terms of mechanical properties, prevention of generation of a gel-like substance, and the like.

The block copolymers (c) and (d) each having a carboxyl group or a derivative group thereof as a compatibilizer include a styrene / ethylene / butadiene copolymer block and a styrene-based polymer block. Block copolymer consisting of, or an olefin-based polymer block and a styrene-based polymer block, a maleic anhydride, maleic acid, fumaric acid, itaconic acid, acrylic acid, crotonic acid, maleic imide And the like. Modified with a carboxylic acid or a derivative thereof, and among them, the block copolymer modified with maleic anhydride is preferably used. In that case, the amount of modification by maleic anhydride in the block copolymer is:
0.5-3% by weight based on the total weight of the block copolymer
Is preferable in terms of mechanical properties of the polyester resin composition and molded articles obtained therefrom, prevention of generation of a gel-like substance, and the like.

The above-mentioned polymer compatibilizer used in the present invention has a melt flow rate (MFR) of about 1 to about 1.
3 g / 10 min is preferable from the viewpoint of film strength.

The polyester resin composition of the present invention needs to contain the above-mentioned polyester resin, olefin polymer and compatibilizer in proportions satisfying the following formulas (1) and (2). It is. 10 ≦ X + Y ≦ 100 (1) 1 ≦ X / Y ≦ 90 (2) [where X and Y are polyester resin 100, respectively]
It represents the content (parts by weight) of the olefin polymer and the compatibilizer with respect to parts by weight. ]

The total content (X + Y) of the olefin polymer and the compatibilizer in the polyester resin composition is
If the amount is less than 10 parts by weight based on 100 parts by weight of the polyester resin and deviates from the above formula (1), the polyester resin composition and a molded article such as a film comprising the same when exposed to hydrogen peroxide. Hydrogen peroxide is absorbed, causing swelling, generation of bubbles, separation from a substrate such as paper, and the like. On the other hand, the total content of the olefin polymer and the compatibilizer in the polyester resin composition (X + Y)
Is more than 100 parts by weight with respect to 100 parts by weight of the polyester resin and still deviates from the above formula (1), the gas barrier properties of the polyester resin composition and molded articles such as films made of the same, and the flavor. Barrier properties are impaired. In the polyester resin composition of the present invention, the total content of the olefin polymer and the compatibilizing agent is 30 to 70 parts by weight based on 100 parts by weight of the polyester resin.
By weight, the resistance to hydrogen peroxide (hereinafter sometimes referred to as “hydrogen peroxide resistance”) is improved, and swelling, generation of bubbles, separation from the substrate, etc. can be effectively prevented, It is more preferable because the gas barrier property and the flavor barrier property can be further improved.

When the content ratio (X / Y) of the olefin polymer to the compatibilizer in the polyester resin composition is less than 1 outside the above formula (2), the phase in the polyester resin composition may be reduced. The content of the solubilizing agent becomes too high to generate a gel. On the other hand, the ratio of the olefin polymer and the compatibilizer in the polyester resin composition (X
If / Y) deviates from the above formula (2) and is greater than 90, the content of the compatibilizer in the polyester resin composition will be too low, and the ratio between the polyester resin phase and the olefin-based polymer phase will be too low. Is not achieved, and the physical properties of the polyester resin composition and a molded article formed therefrom, such as mechanical properties such as strength and elongation, are impaired.
In the polyester resin composition of the present invention, the ratio (X /
More preferably, Y) is in the range of 1 to 40.

Further, the polyester resin composition of the present invention, together with the above-mentioned requirements, comprises a polyester resin, an olefin polymer and a compatibilizer in the following formula (3): E / F ≦ 1 (3) η ₁ (X + Y) / (η ₂ X + η ₃ Y) F = 100 D ₂ D ₃ / D ₁ (D ₃ X + D ₂ Y) [where X and Y are as defined above, η ₁ ,
η ₂ and η ₃ represent the melt viscosities (poise) of the polyester resin, the olefin-based polymer and the compatibilizer at the melt mixing temperature at the time of preparing the polyester resin composition, respectively, and D ₁ , D ₂ and D ₃ are The respective densities at 25 ° C. of the polyester resin, polyolefin polymer and compatibilizer are shown. ] Must be obtained by melt-mixing to satisfy the above. For this purpose, for example, adjustment of the mixing amount of the polyester resin, the olefin polymer and the compatibilizer, selection of the three components (polymers) having a suitable density, and the above-mentioned melting and mixing temperature actually employed. It is necessary to select each component having a viscosity that satisfies the formula (3) of the formula (1) and to appropriately set the melt mixing temperature for forming the polyester resin composition, and the like. The polyester resin composition of the present invention that satisfies the above formula (3) can be obtained by selecting a polymer and employing appropriate melt mixing conditions.

The above-mentioned polyester resin composition having a value of E / F larger than 1 and not satisfying the formula (3) and molded articles such as films obtained therefrom are prepared by melt-mixing the polyester resin composition. Even if it is, the flavor barrier property is low. Although the reason is not clear, when the value of E / F is larger than 1, the polyester resin does not form a matrix in the polyester resin composition, and the olefin polymer and / or the compatibilizer form the matrix. This is presumed to be due to the fact that the flavor barrier property inherent to the polyester resin is not exhibited. As the E / F value is smaller, the flavor barrier properties of the polyester resin composition and a molded article such as a film made of the same become better, but on the other hand, if the E / F value is too small, the peroxidation resistance is reduced. The value of E / F is preferably in the range of 0.1 to 1 since problems such as a decrease in hydrogenity tend to occur.

In the polyester resin composition of the present invention, when an alkali metal salt of an aliphatic carboxylic acid having 1 to 15 carbon atoms is contained in addition to the above-mentioned components, swelling during sterilization with hydrogen peroxide is improved. It can be suppressed effectively. Examples of the alkali metal salt of an aliphatic carboxylic acid having 1 to 15 carbon atoms include sodium formate, sodium acetate, potassium acetate, sodium propionate, potassium propionate, sodium butyrate, potassium butyrate, sodium valerate, potassium valerate, and caproic acid. Sodium, potassium caproate, sodium caprate, potassium caprate, sodium laurate, potassium laurate, sodium myristate, potassium myristate, and the like.From the viewpoint of the mechanical strength of molded products such as films, sodium acetate, Potassium acetate is preferred. 1 to 1 carbon atoms
The content of the alkali metal salt of the aliphatic carboxylic acid of 5 is preferably in the range of 100 to 10000 ppm, and more preferably in the range of 1500 to 8000 ppm in terms of alkali metal atom, based on 100 parts by weight of the polyester resin. Is more preferred.

The polyester resin in the present invention is a raw material for forming a polyester resin comprising a dicarboxylic acid component composed of terephthalic acid or a lower alkyl ester thereof and a diol component mainly composed of ethylene glycol, and comprises naphthalenedicarboxylic acid or an ester thereof. An esterification reaction or a transesterification reaction is carried out using a raw material for forming a polyester resin containing the forming derivative in such a ratio that the copolymerization ratio of naphthalenedicarboxylic acid units in the polyester resin is 5 to 40 mol% as described above. After the low polymer is produced by melt-polycondensation, the polyester can be produced by subjecting the low polymer to a melt polycondensation, and then, if desired, can be produced by solid-phase polymerization.

Although not particularly limited, a preferred method for obtaining a polyester resin will be described in more detail. When the above-mentioned low polymer is produced by an esterification reaction, the above-mentioned raw material for forming a polyester resin is used. About 23 kg under normal pressure or absolute pressure of 3 kg / cm ² or less.
The esterification reaction is preferably performed at a temperature of 0 to 280 ° C. In this case, the ratio of the dicarboxylic acid component to the diol component is preferably set to a molar ratio of 1: 1 to 1: 1.5.
In the case where a low polymer is produced by a transesterification reaction, the above-mentioned raw material for forming a polyester resin is transesterified at a temperature of 170 to 220 ° C. in the presence of a transesterification reaction catalyst under normal pressure or near normal pressure. It is good to react. In this case, the ratio of the dicarboxylic acid diester component to the diol component is preferably 1: 1 to 1: 3. Examples of the transesterification catalyst to be used include those similar to the titanium compounds, manganese compounds and cobalt compounds exemplified above as the metal compounds contained in the polyester resin composition of the present invention.

The above-mentioned melt polycondensation for obtaining a polyester from a low polymer is usually carried out in the presence of a polycondensation catalyst such as germanium dioxide or antimony trioxide.
It can be performed at a temperature of 60 to 290 ° C. In this case, it is preferable to carry out this polycondensation reaction using antimony trioxide in an amount in the range of 500 to 3,000 ppm, since a polyester having almost no bubbles can be obtained when treated with hydrogen peroxide. Further, the above-mentioned melt polycondensation reaction is performed by converting a phosphorus compound such as phosphoric acid, phosphorous acid, trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, triphenyl phosphate into 50 to 100 p in terms of phosphorus atom.
By adding about pm, the resulting polyester can be prevented from being colored by thermal decomposition or a decrease in molecular weight during melt molding,
Hydrogen peroxide resistance is preferable because it can be improved. Such a melt polycondensation usually results in an intrinsic viscosity of 0.1.
A polyester of 50-0.80 dl / g is obtained.

The above-mentioned esterification, transesterification, and polycondensation reactions may be carried out by adding a diethylene glycol by-product inhibitor such as tetraethylammonium hydroxide, triethanolamine or triethylamine, if necessary. .

The polyester obtained by the above-mentioned melt polycondensation reaction can be generally formed into chips or pellets and, if desired, pre-crystallized at a temperature of 190 ° C. or lower, and then subjected to solid-state polymerization. The solid-phase polymerization is usually carried out under reduced pressure or under the flow of an inert gas such as nitrogen gas while flowing the chips (pellets) so that the chips (pellets) do not fuse with each other.
Heating to 240 ° C is performed. Considering the mechanical properties of the obtained polyester resin and the viscosity at the time of melt molding, the ultimate viscosity of the finally obtained polyester resin (30 ° C. in a mixed solvent of phenol / tetrachloroethane and the like by weight) is considered.
Is preferably in the range of about 0.60 to 1.50 dl / g. Then, by performing the above-described series of steps, a polyester resin preferably used in the present invention can be obtained.

As the olefin-based polymer and the compatibilizing agent, those which give a polyester resin composition satisfying the above-mentioned formula (3) when melt-mixed with a polyester resin at a predetermined temperature are commercially available. It is better to use it by selecting from among those that are available.

As a method for preparing the polyester resin composition of the present invention, the polyester resin phase forms a matrix in the obtained polyester resin composition, and the olefin-based polymer phase contains the compatibility of the compatibilizer in the matrix. In order to uniformly and finely disperse by the chemical action, it is necessary to melt-mix the above components under conditions that satisfy the above-mentioned formula (3). As a melt mixing method therefor, for example, after a polyester resin is produced in a polymerization tank, an olefin polymer and a compatibilizer may be added and melt mixed in the polymerization tank. It is preferable to use a kneading device such as an extruder in consideration of the point of uniformity and the like. The melt-kneading temperature at that time is preferably about 220 to 300 ° C. from the viewpoint that a polyester resin composition having good physical properties can be obtained.
The temperature is more preferably in the range of 0 to 280 ° C. The melt mixing temperature when preparing the polyester resin composition is 220 ° C.
If it is less than the above, the reaction between the functional group in the compatibilizer and the terminal hydroxyl group or carboxyl group of the polyester resin will not be sufficiently performed, and the polyester resin composition or molding excellent in mechanical properties such as strength and elongation will not be performed. Products are difficult to obtain,
On the other hand, when the temperature exceeds 300 ° C., the thermal decomposition of the polymer becomes remarkable, and the mechanical properties such as the strength and the elongation of the polyester resin composition and the molded article made of the same also tend to decrease.

The method for dispersing the metal compound is not particularly limited, and the metal compound may be used at any time before, during, or after melt-kneading the polyester resin, the olefin-based polymer and the compatibilizer. Or a metal compound is added during the production of the polyester resin to prepare a composition of the polyester resin and the metal compound, and the composition is melt-mixed with an olefin polymer and a compatibilizer. Any of these methods may be employed.

The form of the polyester resin composition of the present invention is not particularly limited, but if it is formed into a form such as a pellet or a chip, it can be conveniently used for various moldings.

The polyester resin composition of the present invention may contain various conventionally known additives depending on the use and the like, as long as the object of the present invention is not impaired. Examples include decomposition inhibitors, coloring agents, flame retardants, antioxidants, ultraviolet absorbers, antistatic agents, lubricants, and the like. However, when the polyester resin composition of the present invention is used in direct contact with a food such as an inner coating material of a food paper container, it is necessary to select the type of additive in consideration of safety.

The polyester resin composition of the present invention is heated and melted, for example, into a film, sheet, plate, tubular,
Various molded products such as a hollow molded product, a molded product, and a laminate can be obtained. As the molding method at that time, any of the molding methods used for molding a thermoplastic resin can be used, for example, an extrusion molding method, a casting molding method, an extrusion blow molding method, an injection molding method, an injection blow molding method, a calender molding. It can be formed by a press forming method, a press forming method, various laminating methods, or the like.

Among them, the polyester resin composition of the present invention takes advantage of its good gas barrier properties, flavor barrier properties, heat sealing properties, resistance to hydrogen peroxide, mechanical properties, and the like to make use of the packaging films, sheets, and bottles. It can be used particularly effectively as packaging containers of other shapes, and is particularly suitable as a film or sheet container for food packaging. When a film or sheet is formed from the polyester resin composition of the present invention, its thickness is not particularly limited and can be appropriately set depending on the application and the like, but is generally set to a thickness of about 0.005 to 1 mm. Is good.

When a film or sheet is formed from the polyester resin composition of the present invention, any of the conventionally known methods for producing a film or sheet using a thermoplastic resin can be employed. Examples include an inflation extrusion molding method, a casting molding method, a calendar molding method, and a press molding method in which molding is performed while introducing a fluid into a cylindrical body extruded from a die.
Among them, in order to produce films in large quantities industrially, molding is easy, product loss is small,
For reasons such as low production cost, an extrusion molding method is preferably used, and particularly, an inflation extrusion molding method is preferably used. And when manufacturing a film by inflation extrusion molding method, by adjusting the pressure and amount of fluid introduced into the cylindrical body extruded from the annular die, the take-up speed of the extruded film, etc., as necessary In addition, a stretched film can be obtained simultaneously with inflation extrusion.

The film or sheet comprising the polyester resin composition of the present invention may be in the form of a laminate of two or three or more layers with another base material. For example, polyolefins such as polyethylene and polypropylene, polyamide, polyvinyl chloride, polyvinylidene chloride, polyesters other than those described above, thermoplastic polymers such as ethylene-vinyl alcohol copolymer, paper, fabric, metal foil and the like. And one or more of these substrates can be used. In this case, the production method of the laminate is not particularly limited, and a conventionally known lamination method such as an extrusion lamination method, a dry lamination method, a wet lamination method, or a hot melt lamination method may be employed.

In particular, a laminate obtained by laminating a film layer made of the polyester resin composition of the present invention on paper can be effectively used as a paper container material for fruit juice drinks and other drinks. The paper container having a film layer made of the polyester resin composition of the present invention on the inner surface, even when sterilized with hydrogen peroxide, swells, generates bubbles in the polyester resin composition, the paper substrate and the polyester resin composition And the aroma and taste of the beverage filled in the paper container can be kept safely and well over a long period of time.

[0041]

EXAMPLES The present invention will be described below in more detail with reference to examples and the like, but the present invention is not limited thereto. In the following examples, the intrinsic viscosity of the polyester resin, the melt viscosity of each polymer, and the swelling property of the film obtained from the polyester resin composition by hydrogen peroxide, the flavor barrier property, the heat sealing property and the elongation are as follows. Was measured or evaluated.

1. Intrinsic viscosity of polyester resin In a phenol / tetrachloroethane equal weight mixed solvent, 3
At 0 ° C, Ubbelohde viscometer (“HRK-3” manufactured by Hayashi Seisakusho)
Mold ").

2. Melt viscosity of each polymer Each polymer was heated and melted at 280 ° C., and measured using a Capillograph (“Capillograph 1C” manufactured by Toyo Seiki Seisaku-sho, Ltd.).

3. Swellability of Film by Hydrogen Peroxide Using the polyester resin composition of the following example or comparative example, at a temperature of 280 ° C. and a pressing pressure of 100 kg / cm ^2.
Press molding under the conditions described above to produce a film having a thickness of 100 μm, and from the film, length × width = 100 mm × 100
mm test piece, immersed in 35% hydrogen peroxide at a temperature of 90 ° C. for 60 seconds,
Immersed in 400 ml of distilled water at 400 ° C. for 1 hour, and measured the concentration of hydrogen peroxide eluted in the distilled water using a test paper.
The index was used as an index of swelling by hydrogen peroxide.

4. Flavor Barrier Property of Film Using the polyester resin composition of the following example or comparative example, the temperature was 280 ° C. and the pressing pressure was 100 kg / cm ^2.
Press-molded under the conditions described above to produce a film having a thickness of 500 μm, and from the film, length × width = 20 mm × 50 mm
Cut out a test piece of the size of, and use it for orange juice (Ehime mandarin orange "POM straight juice") 50ml
After the film was immersed in the solution at a temperature of 25 ° C. for 12 days, the film was taken out of the orange juice, and the amount of limonene remaining in the orange juice was quantified by bromination titration to obtain an index of flavor barrier properties.

5. Heat Sealability of Film Using the polyester resin composition of the following example or comparative example, a film having a thickness of 100 μm was produced by press molding under the conditions of a temperature of 280 ° C. and a pressing pressure of 100 kg / cm ^2. Two test pieces with dimensions of length x width = 50 mm x 50 mm were cut out, and the sealing pressure was 1.2 kg / c.
Heat sealing is performed using a heat sealing device “YSS type heat sealer” (manufactured by Yasuda Seiki Seisakusho) under conditions of m ² and sealing time of 1.4 seconds, and the lower limit temperature at which heat sealing is possible is determined. It was an index of sex.

6 Elongation of Film Using the polyester resin composition of the following example or comparative example, a temperature of 280 ° C. and a pressing pressure of 100 kg / cm ^2.
Press-molded under the conditions described above to produce a film having a thickness of 100 μm, and from the film, length × width = 80 mm × 15 mm
Was cut out and its elongation was measured according to ASTM D882.

Example 1 (1) A slurry comprising 62.3 parts by weight of ethylene glycol, 44.3 parts by weight of dimethyl terephthalate and 55.7 parts by weight of dimethyl 2,6-naphthalenedicarboxylate (diol component: Using a carboxylic acid dimethyl ester molar ratio of 2.25: 1, manganese acetate tetrahydrate 2000 ppm (manganese atom conversion: 448)
(ppm) in the presence of 170 ppm to a temperature of 220 ° C. over 2 hours and 30 minutes by gradually increasing the temperature to carry out a transesterification reaction to obtain a composition comprising a low polymer and manganese acetate tetrahydrate. Manufactured. Next, 2,000 ppm of antimony trioxide was added as a catalyst, and the pressure was reduced to 28 Torr under an absolute pressure of 1 Torr.
Polycondensing the composition containing the low polymer at a temperature of 0 ° C.,
A composition comprising a polyester resin having an intrinsic viscosity of 0.75 dl / g and manganese acetate tetrahydrate was prepared. This composition was extruded into a strand from a nozzle to produce a columnar chip. The melt viscosity at 280 ° C. (η ₁ ) and the density at 25 ° C. (D ₁ ) of this polyester resin were as shown in Table 1 below.

(2) Apart from the above (1), a twin screw extruder (φ = 30 mm; “TEX30SS CR” manufactured by Japan Steel Works, Ltd.)
W-2V ") and high-density polyethylene (" Nipolon Hard 5700 "manufactured by Tosoh Corporation; melt flow rate 1 g / 10)
), And 45 parts by weight of an ethylene / acrylic acid copolymer ("Yukaron EAA A201K" manufactured by Mitsubishi Chemical Corporation; melt flow rate 5 g / 10 minutes; acrylic acid content 7.0 w)
(% by weight) was melt-kneaded at 200 ° C., extruded into strands, and then cut to produce a blend chip composed of both polymers. The melt viscosity (η ₂ ), (η ₃ ), density (D ₂ ), and (D ₃ ) at 280 ° C. of the high-density polyethylene and ethylene / acrylic acid copolymer used here were measured. And as shown in Table 1 below.

(3) In the same twin-screw extruder as used in (2), 100 parts by weight of the chips obtained in (1) and 50 parts by weight of the blended chips obtained in (2) are used. Parts, melt-kneaded at 280 ° C., extruded and cut to obtain a copolymer of polyethylene terephthalate with naphthalenedicarboxylic acid units, manganese acetate 4
Chips of polyester resin composition containing water salt, high density polyethylene and ethylene / acrylic acid copolymer were produced. (4) The chip obtained in the above (3) is heated and vacuum-dried at 90 ° C. for 16 hours, and then is press-molded at 280 ° C. according to the above-mentioned respective test methods to have a thickness of 100 μm.
m and 500 μm of the film were produced, and the swellability of the film with hydrogen peroxide, the flavor barrier property, the heat sealability and the elongation were measured or evaluated by the method described above. Was as shown in FIG.

<Example 2> (1) 68.3 parts by weight of ethylene glycol, 71.3 parts by weight of dimethyl terephthalate, 29.8 parts by weight of dimethyl 2,6-naphthalenedicarboxylate and 20,000 ppm of sodium acetate (sodium atom Slurry (converted: 5610 ppm) (diol component: dicarboxylic acid dimethyl ester molar ratio = 2.2)
5: 1) using tetraisopropyl titanate 300
In the presence of 0 ppm (equivalent to 506 ppm of titanium atoms) from a temperature of 170 ° C. to a temperature of 220 ° C. for 2 hours 3
The temperature was gradually raised over 0 minutes to carry out a transesterification reaction to produce a composition comprising a low polymer, tetraisopropyl titanate and sodium acetate. Next, the composition containing the above low polymer is polycondensed at a temperature of 280 ° C. under a reduced pressure of 1 Torr absolute pressure and comprises a polyester resin having an intrinsic viscosity of 0.68 dl / g, tetraisopropyl titanate and sodium acetate. A composition was prepared. This composition was extruded from a nozzle into a strand to produce a columnar chip.
The melt viscosity at 280 ° C. (η ₁ ) and the density at 25 ° C. (D ₁ ) of this polyester resin were as shown in Table 1 below.

(2) Separately from the above (1), the same twin-screw extruder as used in (2) of Example 1 was mixed with low-density polyethylene ("Mirason F9693" manufactured by Mitsui Petrochemical Industries, Ltd.).
P "; 32 parts by weight of a melt flow rate (1.1 g / 10 minutes) and a block copolymer (manufactured by Asahi Kasei Corporation) comprising a styrene / ethylene / butadiene copolymer block modified with maleic anhydride and a styrene polymer block "TUFTEC M1913"; melt flow rate 1g / 10
Was fed at a rate of 8 parts by weight, melt-kneaded at 200 ° C., extruded into strands, and cut to produce columnar chips. The low-density polyethylene and block copolymer used here had a melt viscosity at 280 ° C (η ₂ ), (η ₃ ) and a density at 25 ° C (D ₂ ),
When (D ₃ ) was measured, it was as shown in Table 1 below.

(3) In the same twin-screw extruder as used in (2) above, 100 parts by weight of the chips obtained in (1) and 40 parts by weight of the blended chips obtained in (2) are used. Parts, melt-kneaded at 280 ° C., extruded, cut, and mixed with a copolymerized polyethylene terephthalate resin of naphthalenedicarboxylic acid units, tetraisopropyl titanate, sodium acetate, low-density polyethylene and maleic anhydride. A chip of a polyester resin composition containing a block copolymer composed of a modified styrene / ethylene / butadiene copolymer block and a styrene polymer block was produced. (4) After heating and drying the chip obtained in the above (3) at 90 ° C. for 16 hours, it is subjected to press molding at 280 ° C. according to the above-mentioned respective test methods to obtain a film having a thickness of 100 μm or 500 μm. The swelling property of the film with hydrogen peroxide, the flavor barrier property, the heat sealing property and the elongation were measured or evaluated using the above-mentioned methods. The results are shown in Table 1 below. Was.

Example 3 (1) A slurry comprising 62.9 parts by weight of ethylene glycol, 35.0 parts by weight of dimethyl terephthalate, and 66.0 parts by weight of dimethyl 2,6-naphthalenedicarboxylate (diol component: Using a molar ratio of dicarboxylic acid dimethyl ester = 2.25: 1), from the temperature of 170 ° C. to the temperature of 220 ° C. in the presence of 1500 ppm of cobalt acetate (356 ppm in terms of cobalt atoms).
The temperature was gradually raised over a period of 30 minutes to carry out a transesterification reaction to produce a composition comprising a low polymer and cobalt acetate. Next, the above low polymer was polycondensed at a temperature of 280 ° C. under a reduced pressure of 1 Torr absolute pressure, and the intrinsic viscosity was 0.60 dl / g.
A composition comprising a polyester resin and cobalt acetate was prepared. This composition was extruded into a strand from a nozzle to produce a columnar chip. The melt viscosity (η ₁ ) of this polyester resin at 280 ° C. and 25 ° C.
Density (D ₁₎ in the are as shown in Table 1 below.

(2) Apart from the above (1), a linear low-density polyethylene ("Idemitsu Polyethylene-Idemitsu Petrochemical Co., Ltd.") was placed in the same twin-screw extruder as used in (1) of Example 1.
L0134N "; melt flow rate 1 g / 10 minutes) and 60 parts by weight of a zinc ion crosslinked structure of ethylene / methacrylic acid copolymer (" Himilan 1705 "manufactured by DuPont-Mitsui Polychemicals; melt flow rate 5 g /
10 minutes) at a rate of 10 parts by weight, melt-kneaded at 200 ° C., extruded into strands, and cut to produce columnar chips. The melt viscosities (η ₂ ) and (η ₃ ) at 280 ° C. and the density (D at 25 ° C.) of the linear low-density polyethylene and block copolymer used here were used.
₂ ) and (D ₃ ) were measured and found to be as shown in Table 1 below.

(3) In the same twin-screw extruder as used in (2) above, 100 parts by weight of the chips obtained in (1) and 70 parts by weight of the blended chips obtained in (2) are used. Parts, melt-kneaded at 280 ° C., extruded and cut, copolymerized polyethylene terephthalate resin of naphthalenedicarboxylic acid unit, cobalt acetate,
A chip of a polyester resin composition containing a block copolymer consisting of a styrene / ethylene / butadiene copolymer block modified with low-density polyethylene and maleic anhydride and a styrene polymer block was produced. (4) After heating and drying the chip obtained in the above (3) at 90 ° C. for 16 hours, it is subjected to press molding at 280 ° C. according to the above-mentioned respective test methods to obtain a film having a thickness of 100 μm or 500 μm. The swelling property of the film with hydrogen peroxide, the flavor barrier property, the heat sealing property and the elongation were measured or evaluated using the above-mentioned methods. The results are shown in Table 1 below. Was.

Example 4 (1) A slurry comprising 61.5 parts by weight of ethylene glycol, 25.7 parts by weight of dimethyl terephthalate and 75.3 parts by weight of dimethyl 2,6-naphthalenedicarboxylate (diol component: Using a molar ratio of dicarboxylic acid dimethyl ester = 2.25: 1), manganese acetate tetrahydrate 500 ppm (manganese atom conversion: 112 p)
pm), and in the presence of 500 ppm of cobalt acetate tetrahydrate (calculated as cobalt atoms: 119 ppm), the temperature was gradually raised from 170 ° C. to 220 ° C. over 2 hours and 30 minutes to carry out a transesterification reaction. A composition comprising a low polymer, manganese acetate tetrahydrate, and cobalt acetate tetrahydrate was produced. Next, 2000 ppm of antimony trioxide was used as a catalyst.
And the above-mentioned low polymer is polycondensed at a temperature of 280 ° C. under a reduced pressure of 1 Torr absolute, comprising a polyester resin having an intrinsic viscosity of 0.55 dl / g, manganese acetate tetrahydrate and cobalt acetate tetrahydrate. A composition was prepared. This composition was extruded from a nozzle into a strand to produce a columnar chip. The melt viscosity at 280 ° C. (η ₁ ) and the density at 25 ° C. (D ₁ ) of this polyester resin were as shown in Table 1 below.

(2) Separately from the above (1), a twin screw extruder (φ = 30 mm; “TEX30SS CR” manufactured by Japan Steel Works, Ltd.)
W-2V ") and high-density polyethylene (" Nipolon Hard 5700 "manufactured by Tosoh Corporation; melt flow rate 1 g / 10)
), And 70 parts by weight of an ethylene / acrylic acid copolymer ("Yukalon EAA A201K" manufactured by Mitsubishi Chemical Corporation; melt flow rate 5 g / 10 minutes; acrylic acid content 7.0 w)
(t%) at a rate of 15 parts by weight, melt-kneaded at 200 ° C., extruded into strands, and cut to produce a blend chip composed of both polymers. The melt viscosity (η ₂ ), (η ₃ ), density (D ₂ ), and (D ₃ ) at 280 ° C. of the high-density polyethylene and ethylene / acrylic acid copolymer used here were measured. And as shown in Table 1 below.

(3) In the same twin-screw extruder as used in (2) above, 100 parts by weight of the chips obtained in (1) and 85 parts by weight of the blended chips obtained in (2) are used. Parts, melt-kneaded at 280 ° C., extruded and cut to obtain a copolymer of polyethylene terephthalate with naphthalenedicarboxylic acid units, manganese acetate 4
Chips of polyester resin composition containing water salt, cobalt acetate tetrahydrate, high density polyethylene and ethylene / acrylic acid copolymer were produced. (4) The chips obtained in (3) are vacuum-dried at 90 ° C. for 16 hours, and then are pressed and formed at 280 ° C. according to the above-mentioned respective test methods, and the films having a thickness of 100 μm and 500 μm are used. The swelling property of the film with hydrogen peroxide, the flavor barrier property, the heat sealing property and the elongation were measured or evaluated using the above-mentioned methods. The results are shown in Table 1 below. Was.

Comparative Example 1 (1) A slurry comprising 72.6 parts by weight of ethylene glycol, 70.0 parts by weight of dimethyl terephthalate and 30.0 parts by weight of dimethyl isophthalate (diol component: dimethyl dicarboxylate) Molar ratio =
2.25: 1) using manganese acetate tetrahydrate 2000
ppm (manganese atom conversion: 448 ppm) in the presence of 170 ° C. to 220 ° C. for 2 hours 3
The temperature was gradually raised over 0 minutes to carry out a transesterification reaction to produce a composition comprising a low polymer and manganese acetate tetrahydrate. Next, 2000 pp of antimony trioxide was used as a catalyst.
m, and the composition containing the low polymer is polycondensed at a temperature of 280 ° C. under a reduced pressure of 1 Torr absolute pressure, and the intrinsic viscosity is reduced to 0.1.
68 dl / g polyester resin and manganese acetate 4
A composition comprising a water salt was prepared. This polymer was extruded from a nozzle into a strand to produce a columnar chip.
The melt viscosity (η ₁ ) at 280 ° C. and the density (D ₁ ) at 25 ° C. of this polyester resin were as shown in Table 2 below.

(2) In the same twin-screw extruder used in Example 1, 45 parts by weight of the same high-density polyethylene as used in Example 1 (2), and in Example 1 (2) The same ethylene / acrylic acid copolymer as that used in (1) was supplied at a ratio of 5 parts by weight, melt-kneaded at 200 ° C., extruded into strands, and cut to produce columnar chips. (3) To the same twin-screw extruder used in Example 1, 100 parts by weight of the chips obtained in (1) and 50 parts by weight of the blended chips obtained in (2) are supplied. After melt-kneading at 280 ° C, extruding and cutting,
A chip of a polyester resin composition containing a polyethylene terephthalate resin copolymerized with isophthalic acid units, manganese acetate tetrahydrate, high-density polyethylene and an ethylene / acrylic acid copolymer was produced. (4) After heating and drying the chip obtained in the above (2) at 90 ° C. for 16 hours, using it, press-mold at 280 ° C. according to the above-mentioned test methods, and obtain a film having a thickness of 100 μm or 500 μm. The swelling property of the film with hydrogen peroxide, the flavor barrier property, the heat sealing property and the elongation were measured or evaluated using the above method, and the results are as shown in Table 2 below. Was.

Comparative Example 2 (1) Slurry comprising 62.9 parts by weight of ethylene glycol, 35.0 parts by weight of dimethyl terephthalate, and 66.0 parts by weight of dimethyl 2,6-naphthalenedicarboxylate (diol component: Using carboxylic acid dimethyl ester molar ratio = 2.25: 1), manganese acetate tetrahydrate 2000 ppm (manganese atom conversion: 448 pp)
In the presence of m), the temperature was gradually raised from a temperature of 170 ° C. to a temperature of 220 ° C. over 2 hours and 30 minutes to carry out a transesterification reaction to form a composition comprising a low polymer and manganese acetate tetrahydrate. Manufactured. Next, 2,000 ppm of antimony trioxide was added as a catalyst, and the pressure was reduced to 28 Torr under an absolute pressure of 1 Torr.
Polycondensing the composition containing the low polymer at a temperature of 0 ° C.,
A composition comprising a polyester resin having an intrinsic viscosity of 0.59 dl / g and manganese acetate tetrahydrate was prepared. This polymer was extruded from a nozzle into a strand to produce a columnar chip. The melt viscosity at 280 ° C. (η ₁ ) and the density at 25 ° C. (D ₁ ) of this polyester resin were as shown in Table 1 below.

(2) In the same twin-screw extruder as used in Example 1, 100 parts by weight of low-density polyethylene (“Petrocene 204” manufactured by Tosoh Corporation; melt flow rate 7 g / 10 min) was added. The same ethylene / acrylic acid copolymer used in 1 (2) was supplied at a rate of 10 parts by weight, melt-kneaded at 200 ° C., extruded into strands, and cut to produce columnar chips. . (3) To the same twin screw extruder used in Example 1, 100 parts by weight of the chips obtained in (1) and 110 parts by weight of the blended chips obtained in (2) are supplied. , Melt-kneaded at 280 ° C, extruded and cut, polyester resin composition containing polyethylene terephthalate resin copolymerized with naphthalenedicarboxylic acid units, manganese acetate tetrahydrate, low density polyethylene and ethylene / acrylic acid copolymer Product chips were manufactured. (4) After heating and drying the chip obtained in the above (2) at 90 ° C. for 16 hours, using it, press-mold at 280 ° C. according to the above-mentioned test methods, and obtain a film having a thickness of 100 μm or 500 μm. The swelling property of the film with hydrogen peroxide, the flavor barrier property, the heat sealing property and the elongation were measured or evaluated using the above method, and the results are as shown in Table 2 below. Was.

[0064]

[Table 1]

[0065]

[Table 2]

From the results of Tables 1 and 2, at least one metal compound selected from the group consisting of a titanium compound, a manganese compound and a cobalt compound was added to 100 parts by weight of polyester resin in terms of metal atoms.
A polyethylene terephthalate-based resin, an olefin-based polymer and a compatibilizing agent, each containing up to 1000 ppm and having a naphthalenedicarboxylic acid unit copolymerized in an amount of 5 to 40 mol%, satisfy the above-mentioned formulas (1) and (2). The films obtained from the polyester resin compositions of Examples 1 to 4 obtained by melting and mixing to satisfy the formula (3) are excellent in hydrogen peroxide resistance, and No swelling (incorporation of hydrogen peroxide into the film) even when immersed in water, and therefore, there is almost no elution of hydrogen peroxide into distilled water, indicating that the composition is excellent in safety.
In addition, in the films of Examples 1 to 4, limonene, which is a kind of aroma component of orange juice, remains in the orange juice forever without being absorbed or absorbed by the film, and the scent of the orange juice is favorably maintained. It can be seen that the flavor barrier property is good, the heat seal temperature is appropriate, and the handleability and heat sealability are excellent.

On the other hand, from the results of Comparative Example 1, when isophthalic acid was used as the copolymerization component of the polyester resin instead of naphthalenedicarboxylic acid, the amount of hydrogen peroxide eluted was large, resulting in poor safety. You can see that there is. Furthermore, from the result of Comparative Example 2, the above-described equation (1)
In the case where the value of X + Y is larger than 100 and the value of E / F in the formula (3) is larger than 1 and out of the range of the present invention, the residual amount of limonene in the orange juice is significantly reduced. It can be seen that the flavor barrier property is inferior.

Example 5 (1) Using a chip of the polyester resin composition obtained in (4) of Example 1, melt extrusion molding was performed at a temperature of 280 ° C. to produce a film having a thickness of 20 μm. . The film was laminated on a paper substrate (200 μm thick) for a paper container by extrusion lamination to produce a laminate. Using this laminate, the polyester resin composition film layer is placed inside, and molded into a container (bending and heat sealing; heat sealing temperature: 190 ° C.) in accordance with a conventional method to make a juice paper container (200 ml in content). Was manufactured. (2) The paper container obtained in the above (1) is filled with a 75% hydrogen peroxide solution at 75 ° C., left for 30 seconds to perform a sterilization treatment, and then the hydrogen peroxide solution is removed from the paper container. Washed three times with purified water (200 ml of purified water each time). (3) The paper container obtained in the above (2) is filled with pre-sterilized orange juice (180 ml /
(One paper container), mouth closed. (4) The orange juice in the paper container obtained in the above (3) was stored at room temperature for one month, opened, and tasted, and both the aroma and taste were good.

[0069]

The products such as the polyester resin composition of the present invention and molded products such as films made of the same have excellent resistance to hydrogen peroxide, and when treated with hydrogen peroxide, swell and generate bubbles. No peeling from the substrate occurs. Therefore, the polyester resin composition of the present invention or a molded article such as a film made of the same may be sterilized with hydrogen peroxide using a packaging material, a packaging container, or the like that comes into direct contact with food. It is excellent in safety without any fear of dissolving in foods, and is excellent in processability and operability when manufacturing products such as food containers.
In addition, products such as the polyester resin composition of the present invention and molded products such as films made of the same have excellent flavor barrier properties and gas barrier properties, so that they can be effectively used in a wide range of fields including food packaging materials. Can be. Furthermore, the polyester resin composition of the present invention and molded articles such as a film comprising the same have heat sealability,
Because of its excellent mechanical properties such as elongation and strength, it is excellent in handling and durability.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08J 5/18 CFD C08J 5/18 CFD C08K 3/10 C08K 3/10 // (C08L 67/02 23:02 23:08 23 : 26 53:00)

Claims (10)

[Claims] (1) (i) (A) mainly comprising a diol unit mainly composed of an ethylene glycol unit and a dicarboxylic acid unit mainly composed of a terephthalic acid unit, and a naphthalenedicarboxylic acid unit based on the total number of moles of all structural units. (B) at least one metal compound selected from the group consisting of titanium compounds, manganese compounds and cobalt compounds; (C) olefin polymers; and (D) compatibilization. (Ii) 100 to 1000 parts by weight of a polyester resin, in terms of a metal atom, 100 to 1000 ppm of a metal compound, an olefin polymer and a compatibilizer in the following formula (100 parts by weight): 1) and Formula (2): 10 ≦ X + Y ≦ 100 (1) 1 ≦ X / Y ≦ 90 (2) [where X and Y are respectively Riesuteru resin 100
It represents the content (parts by weight) of the olefin polymer and the compatibilizer with respect to parts by weight. (Iii) E / F ≦ 1 (3) where E = η ₁ (X + Y) / (η ₂ X + η ₃ Y) F = 100D ₂ D ₃ / D ₁ (D ₃ X + D ₂ Y) wherein X and Y are as defined above, η ₁ ,
η ₂ and η ₃ represent the melt viscosity (poise) at the melt mixing temperature of the polyester resin, the olefin polymer and the compatibilizer at the melt mixing temperature when preparing the polyester resin composition, and D ₁ , D ₂ and D ₃ is a polyester resin, a polyolefin polymer and a compatibilizer, respectively.
Indicates the density at 5 ° C. ] The polyester resin composition is obtained by melt-mixing to satisfy the following condition: 2. (i) (A) Mainly composed of a diol unit mainly composed of an ethylene glycol unit and a dicarboxylic acid unit mainly composed of a terephthalic acid unit, and a naphthalenedicarboxylic acid unit is based on the total number of moles of all structural units. (B) at least one metal compound selected from the group consisting of titanium compounds, manganese compounds and cobalt compounds; (C) an olefin polymer; (D) a compatibilizer. And (E) an alkali metal salt of an aliphatic carboxylic acid having 1 to 15 carbon atoms; (ii) a metal compound in terms of a metal atom with respect to 100 parts by weight of the polyester resin. 100-1000 ppm, carbon number
The alkali metal salt of an aliphatic carboxylic acid of 1 to 15 is 100 to 10000 ppm in terms of alkali metal salt, and the olefin polymer and the compatibilizer are the following formulas (1) and (2): 10 ≦ X + Y ≦ 100 ( 1) 1 ≦ X / Y ≦ 90 (2) wherein X and Y are each a polyester resin 100
It represents the content (parts by weight) of the olefin polymer and the compatibilizer with respect to parts by weight. (Iii) E / F ≦ 1 (3) where E = η ₁ (X + Y) / (η ₂ X + η ₃ Y) F = 100D ₂ D ₃ / D ₁ (D ₃ X + D ₂ Y) wherein X and Y are as defined above, η ₁ ,
η ₂ and η ₃ represent the melt viscosities (poise) of the polyester resin, the olefin-based polymer and the compatibilizer at the melt mixing temperature at the time of preparing the polyester resin composition, respectively, and D ₁ , D ₂ and D ₃ are The respective densities at 25 ° C. of the polyester resin, polyolefin polymer and compatibilizer are shown. ] The polyester resin composition is obtained by melt-mixing to satisfy the following condition: 3. The compatibilizer is an ethylene (meth) acrylic acid copolymer resin; a metal ion crosslinked structure of an ethylene / (meth) acrylic acid copolymer; styrene / ethylene / carboxyl group or a derivative thereof having a carboxyl group or a derivative group thereof. 1 selected from a block copolymer consisting of a butadiene copolymer block and a styrene-based polymer block; and a block copolymer consisting of an olefin-based polymer block having a carboxyl group or a derivative group thereof and a styrene-based polymer block. The polyester resin composition according to claim 1, wherein the polyester resin composition is a kind or two or more kinds of polymers. 4. A molded article comprising the polyester resin composition according to claim 1. 5. The molded article according to claim 4, which is a film. 6. The film according to claim 5, which is used for food. 7. A packaging material comprising the polyester resin composition according to claim 1. 8. The packaging material according to claim 7, which is used for food. 9. A laminate comprising the polyester resin composition layer according to claim 1 and a paper layer. 10. A paper container having an inner surface coated with the polyester resin composition according to claim 1.