JP2002069320A - Resin composition excellent in gas barrier property - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas barrier resin composition furnished with an oxygen- absorbing function (an oxygen-scavenging function), being made its duration of the oxygen-absorbing function longer, and to provide a molded article such as a packaging material and container, excellent in gas barrier properties and oxygen-absorbing properties, and useful for packaging products which are easily deteriorated by oxygen, such as foods, medicaments and cosmetics. SOLUTION: This resin gas barrier composition comprises (A) a gas barrier resin having an oxygen permeability rate of <=500 ml.20 μm/m2.day.atm (20 deg.C, 65%RH), (B) a thermoplastic resin having carbon-carbon double bonds, (C) a transition metal salt, and (D) an inorganic filler.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a gas barrier property, a moisture proof property, and a fragrance retention property which are used for products which are sensitive to oxygen and are easily deteriorated, especially for packaging materials and containers for foods, beverages, pharmaceuticals, cosmetics and the like. The present invention relates to a resin composition having excellent flavor barrier properties and further having an oxygen absorbing ability. Furthermore, the present invention relates to a molded article using such a composition, for example, a packaging material, a container, and the like for foods, beverages, pharmaceuticals, cosmetics, and the like.

[0002]

2. Description of the Related Art Gas barrier resins such as ethylene-
Resins such as vinyl alcohol copolymer (hereinafter sometimes abbreviated as EVOH), polyamide, polyvinyl chloride, and polyacrylonitrile can be melt-molded and have excellent oxygen or carbon dioxide gas barrier properties. Widely used for sheets, bottles, containers and the like. Multilayer plastic packaging materials laminated with layers of thermoplastic resins with excellent moisture resistance and mechanical properties, especially polyolefin resins, are used as containers with excellent oxygen barrier properties in the form of bags, bottles, cups, pouches, etc. It is widely used in various fields such as cosmetics, medicinal chemicals, toiletries and the like.

[0003] Packaging materials using such gas barrier resins are excellent in barrier properties against oxygen and carbon dioxide gas, but are not suitable for metal materials used for canning and the like and glass used for bottles and the like. As described above, the permeability to gas such as oxygen is not always close to zero, and the gas permeates a non-negligible amount of gas. In particular, in packaging materials for food applications, there is a concern that the quality may deteriorate due to oxidation of the contents when stored for a long period of time. Further, when packaging contents that are easily oxidized, it is also desired to prevent deterioration of the contents by scavenging oxygen mixed into the packaging container together with the contents when the contents are packed or filled. Therefore, it has been proposed to mix an oxygen scavenger with a gas barrier resin to give the gas barrier resin an oxygen scavenging function.

[0004] As a method for imparting an oxygen absorbing function (scavenging function) to a gas barrier resin, the following method has been proposed: EVOH is oxidized by adding an oxidation catalyst such as a transition metal to EVOH. A method of causing oxygen to be permeated to react with the EVOH, thereby imparting an oxygen absorbing function to the EVOH (Japanese Patent Laid-Open Publication No.
No. 211444); By adding an oxidation catalyst such as a transition metal to polyvinyl chloride, the polyvinyl chloride is easily oxidized, and oxygen to be permeated reacts with the polyvinyl chloride, whereby the polyvinyl chloride is reacted. A method of imparting an oxygen absorbing function to vinyl (Japanese Patent Application Laid-Open No. 4-45144); a resin composition comprising a polyolefin and an oxidation catalyst is dispersed in EVOH, and oxygen to be permeated and E
By reacting with polyolefin in VOH,
Method for obtaining a resin composition having an oxygen absorbing function
A method of obtaining a resin composition having an oxygen absorbing function by blending EVOH, a polyolefin, and an oxidation catalyst, and reacting oxygen to be permeated with the polyolefin and EVOH (Japanese Patent Laid-Open No. 5-170980). No.).

However, none of the above-mentioned prior arts describes that a thermoplastic resin having a carbon-carbon double bond and an inorganic filler are blended in a gas barrier resin.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide products which are sensitive to oxygen and which are susceptible to deterioration, in particular foods and beverages,
An object of the present invention is to provide a resin composition having excellent gas barrier properties, moisture-proof properties, fragrance retention properties, and flavor barrier properties when packaging pharmaceuticals, cosmetics, and the like. Another object of the present invention is to provide a composition excellent in the effect of scavenging or absorbing oxygen, in addition to the excellent properties such as the gas barrier properties and moisture proof properties described above. Still another object of the present invention is to provide a resin having the above properties. Still another object of the present invention is to provide a molded article having excellent gas barrier properties, oxygen absorption properties, and the like using the above composition.

[0007]

Means for Solving the Problems The first gas barrier resin composition of the present invention has an oxygen permeation rate of 500 ml · 20 μm.
m / m ² · day · atm (20 ° C., 65% RH) or less gas barrier resin (A), thermoplastic resin having carbon-carbon double bond (B), transition metal salt (C) and inorganic filler ( D).

[0008] In a preferred embodiment, the composition has an oxygen absorption rate of 0.01 ml / m ² · day or more.

Further, the second gas barrier resin composition of the present invention has an oxygen transmission rate of 500 ml · 20 μm / m ² ···
It contains a gas-barrier resin (A) of a day.atm (20 ° C., 65% RH) or less, a thermoplastic resin (B) having a carbon-carbon double bond, and an inorganic filler (D), and has an oxygen absorption rate of 0%. 0.01 ml / m ² · day or more.

[0010] In a preferred embodiment, the thermoplastic resin (B) has a carbon-carbon double bond of 0.0001 eq.
/ G or more.

In a preferred embodiment, the thermoplastic resin (B) is a copolymer of an aromatic vinyl compound and a diene compound.

In a preferred embodiment, the thermoplastic resin (B) has the structural formula (I):

[0013]

Embedded image

Wherein R ₁ is an alkyl group having 1 to 10 carbon atoms, an aryl group, an alkylaryl group or an alkoxy group, and R ₂ and R ₃ are each a hydrogen atom and 1 to 10 carbon atoms. alkyl group, a substituted aryl group, an unsubstituted aryl group, -COOR _4, -OCOR _5, a cyano group or a halogen atom,, R ₄ and R ₅ are each independently an alkyl group having 1 to 10 carbon atoms, aryl Group, an alkylaryl group, or an alkoxy group], and has a number average molecular weight of 1,000 to
It is in the range of 500,000.

In a preferred embodiment, the gas barrier resin (A) is at least one selected from the group consisting of a polyvinyl alcohol resin, polyamide, polyvinyl chloride, and polyacrylonitrile.

In a preferred embodiment, the gas barrier resin (A) is an ethylene-vinyl alcohol copolymer having an ethylene content of 5 to 60 mol% and a saponification degree of 90% or more.

In a preferred embodiment, the transition metal salt (C) is at least one selected from iron salts, nickel salts, copper salts, manganese salts, and cobalt salts. This transition metal salt (C) is contained in the composition in an amount of 1 to 1 in terms of a metal element.
It is contained at a rate of 5000 ppm.

In a preferred embodiment, the weight average aspect ratio of the inorganic filler (D) is 3 or more.

In a preferred embodiment, the inorganic filler (D) is talc.

In a preferred embodiment, the resin composition of the present invention contains the gas barrier resin (A) in an amount of 45 to 9%.
8.9% by weight of the thermoplastic resin (B) is 30 to 0.1%
% By weight, and 25 to 1% by weight of the inorganic filler (D).

In a preferred embodiment, in the resin composition of the present invention, particles made of the thermoplastic resin (B) are dispersed in a matrix of the gas barrier resin (A).

The present invention includes a molded article, a multilayer structure, and a multilayer container comprising the above-mentioned gas barrier resin composition.

The present invention includes a multilayer container comprising a multilayer film including a layer made of the above-mentioned gas barrier resin composition and having a total thickness of 300 μm or less.

The present invention includes a multilayer container comprising a layer made of the above-mentioned gas barrier resin composition and formed by extrusion blow molding.

The present invention also includes a cap provided with a gasket comprising the above-mentioned gas barrier resin composition.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION In the present specification, "scavenging" oxygen means absorbing and consuming oxygen from a given environment,
Or to reduce that amount.

The type of the gas barrier resin (A) contained in the resin composition of the present invention is not particularly limited. Any of resins having good gas barrier properties can be used. Such a resin has an oxygen transmission rate of 50
0ml ・ 20μm / m ²・ day ・ atm (20 ℃ 、 6
5% RH) or less is used. This is 20
When measured in an environment at a temperature of 65 ° C. and a relative humidity of 65%, the volume of oxygen permeating through a film having an area of 1 m ² and a thickness of 20 μm per day is 500 ml or less in the presence of a pressure difference of 1 atm. Means that. Oxygen transmission rate is 500ml
If it exceeds 20 μm / m ² · day · atm, the gas barrier performance will not be sufficiently exhibited. In order to obtain good gas barrier properties, the gas barrier resin (A) preferably has a low oxygen permeation rate. Preferably, 100ml ・ 20μ
m / m ² · day · atm or less, more preferably 20 ml · 20 μm / m ² · day · atm or less, and still more preferably 5 ml · 20 μm / m ² · da.
y · atm or less.

By blending such a gas barrier resin (A) and a thermoplastic resin (B) having a carbon-carbon double bond as described below, the resin (B) can be used in addition to the gas barrier effect of the resin (A). Thereby exhibiting an oxygen scavenging effect, and as a result, a resin composition having extremely high gas barrier properties can be obtained.

The type of the gas barrier resin (A) is not particularly limited. As described above, the oxygen transmission rate is 500 ml
Examples of the gas barrier resin (A) satisfying the condition of not more than 20 μm / m ² · day · atm include polyvinyl alcohol-based resin (A1), polyamide (A2),
Polyvinyl chloride (A3), polyacrylonitrile (A
4) and the like are exemplified as typical resins, but are not limited to these resins.

Among the gas barrier resins (A), the polyvinyl alcohol resin (A1) is a homopolymer of vinyl ester or a copolymer of vinyl ester and other monomers (particularly, a copolymer of vinyl ester and ethylene). Copolymer)
Is obtained by saponification using an alkali catalyst or the like.

As the above-mentioned vinyl ester, vinyl acetate is mentioned as a typical compound, but other fatty acid vinyl esters (vinyl propionate, vinyl pivalate, etc.) can also be used.

The degree of saponification of the vinyl ester component of the polyvinyl alcohol resin is preferably 90% or more, more preferably 95% or more, and even more preferably 97% or more.
% Or more. If the saponification degree is less than 90 mol%, the gas barrier properties under high humidity may be reduced. Further, in the case of an ethylene-vinyl alcohol copolymer (EVOH), the thermal stability is deteriorated, and the resulting molded article is liable to generate gels and bumps.

When the polyvinyl alcohol-based resin is composed of a blend of two or more kinds of polyvinyl alcohol-based resins having different degrees of saponification, an average value calculated from the blending weight ratio is defined as the degree of saponification. The saponification degree of such a polyvinyl alcohol-based resin can be determined by a nuclear magnetic resonance (NMR) method.

As the polyvinyl alcohol-based resin (A1) used in the present invention, EVOH is preferable among the above-mentioned gas-barrier resins because it can be melt-molded and has good gas-barrier properties under high humidity.

The EVOH preferably has an ethylene content of 5 to 60 mol%. If the ethylene content is less than 5 mol%, the gas barrier properties under high humidity may decrease, and the melt moldability may also deteriorate. The ethylene content of the EVOH is preferably at least 10 mol%, more preferably 15 mol%.
As described above, it is optimally at least 20 mol%. If the ethylene content exceeds 60 mol%, it is difficult to obtain sufficient gas barrier properties. The ethylene content is preferably at most 55 mol%, more preferably at most 50 mol%. The ethylene content of EVOH can be determined by a nuclear magnetic resonance (NMR) method.

The EVOH preferably used has an ethylene content of 5 to 60 mol% and a saponification degree of 90% or more.

When the EVOH is composed of a blend of two or more EVOHs having different ethylene contents or saponification degrees, the average value calculated from the blending weight ratio is defined as the ethylene content or saponification degree.

However, when two types of EVOH are blended, it is preferable that the difference in ethylene content between them is 15 mol% or less and the difference in saponification degree is 10% or less. If these conditions are not satisfied, the transparency of the resin composition layer is impaired. From the viewpoint of obtaining good transparency, the difference in ethylene content is more preferably 10 mol% or less, and still more preferably 5 mol% or less. Similarly, from the viewpoint of obtaining good transparency, the difference in the degree of saponification is more preferably 7% or less, and still more preferably 5% or less.

Further, a polyvinyl alcohol-based resin (A
1) In particular, EVOH may contain a small amount of another monomer as a copolymer component as long as the object of the present invention is not impaired. Examples of the monomer that can be a copolymerization component include α such as propylene, 1-butene, isobutene, 4-methyl-1-pentene, 1-hexene, and 1-octene.
-Olefins; unsaturated carboxylic acids such as itaconic acid, methacrylic acid, acrylic acid, maleic anhydride, and salts thereof;
Partial or complete esters, nitriles, amides, anhydrides; vinylsilane compounds such as vinyltrimethoxysilane; unsaturated sulfonic acids or salts thereof; alkylthiols; vinylpyrrolidones.

In particular, when the EVOH contains 0.0002 to 0.2 mol% of a vinylsilane compound as a copolymer component, the consistency of the melt viscosity with the base resin at the time of coextrusion molding or coinjection molding is improved. Improved and homogeneous moldings can be produced. Here, examples of the vinylsilane-based compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β-methoxy-ethoxy) silane, and γ-methacryloxypropyltrimethoxysilane. Among them, vinyltrimethoxysilane and vinyltriethoxysilane are preferably used.

Further, when a boron compound is added to EVOH, the melt viscosity of EVOH is improved, and this is effective in that a homogeneous co-extrusion or co-injection molded product can be obtained. Here, examples of the boron compound include boric acids, borate esters, borates, borohydrides, and the like.
Specifically, as boric acids, orthoboric acid (hereinafter, referred to as
Abbreviated as boric acid), metaboric acid, tetraboric acid and the like, boric acid esters such as triethyl borate and trimethyl borate, and boric acid salts of the above-mentioned various boric acids. Metal salts, alkaline earth metal salts, borax and the like. Of these compounds, orthoboric acid is preferred.

When a boron compound is added, its content is from 20 to 2000 ppm, preferably from 50 to 1000 ppm in terms of boron element. By being in this range, it is possible to obtain EVOH in which torque fluctuation during heating and melting is suppressed. If it is less than 20 ppm, such an effect is small, and if it exceeds 2,000 ppm, gelation is likely to occur, resulting in poor moldability.

It is also effective to add 5 to 5000 ppm of an alkali metal salt to EVOH in terms of an alkali metal element in order to improve interlayer adhesion and compatibility.

A more suitable addition amount of the alkali metal salt is 20 to 1000 ppm, preferably 30 to 500 ppm in terms of an alkali metal element. Examples of the alkali metal include lithium, sodium, and potassium.
Examples of the alkali metal salt include an aliphatic carboxylate, an aromatic carboxylate, a phosphate, and a metal complex of a monovalent metal. Examples include sodium acetate, potassium acetate, sodium phosphate, lithium phosphate, sodium stearate, potassium stearate, and sodium salt of ethylenediaminetetraacetic acid. Among them, sodium acetate, potassium acetate and sodium phosphate are preferred.

The phosphoric acid compound is used in an amount of 20 to 500 ppm, more preferably 30 to 300 ppm in terms of a phosphate group, based on EVOH.
It is also preferred to add at a rate of 50 ppm, optimally 50 to 200 ppm. By blending the phosphoric acid compound in the above range, the thermal stability of EVOH can be improved. In particular, problems such as the occurrence of gel-like bumps and coloring during long-time melt molding are likely to occur.

The type of the phosphorus compound added to the EVOH is not particularly limited. Various acids such as phosphoric acid and phosphorous acid and salts thereof can be used. The phosphate may be contained in any form of a first phosphate, a second phosphate, and a third phosphate. The cationic species of the phosphate is not particularly limited, but the phosphate is preferably an alkali metal salt or an alkaline earth metal salt. Among them, phosphoric acid 2
Sodium hydrogen phosphate, potassium dihydrogen phosphate, hydrogen phosphate 2
It is preferable to add the phosphorus compound in the form of sodium and dipotassium hydrogen phosphate.

In addition, if necessary, a heat stabilizer, an ultraviolet absorber, an antioxidant, a coloring agent, a filler, and other resins (polyamide, polyolefin, etc.) may be added to EVOH in advance.
Can also be blended. EV to which the above boron compound, alkali metal salt, phosphorus compound, etc. are added
OH is commercially available.

The preferred melt flow rate (MFR) of EVOH that can be used in the present invention (210 ° C., under a load of 2160 g, based on JIS K7210) is from 0.1 to 100.
g / 10 minutes, more preferably 0.5 to 50 g / 10 minutes, and still more preferably 1 to 30 g / 10 minutes.

The kind of the polyamide resin (A2) which is the gas barrier resin (A) is not particularly limited. For example, polycaproamide (nylon-6), polyundecaneamide (nylon-11), polylauryl lactam (nylon-12), polyhexamethylene adipamide (nylon-
6,6), polyhexamethylene sebacamide (nylon-
6,12) and other aliphatic polyamide homopolymers; caprolactam / laurolactam copolymer (nylon-6 / 1
2), caprolactam / aminoundecanoic acid copolymer (nylon-6 / 11), caprolactam / ω-aminononanoic acid copolymer (nylon-6 / 9), caprolactam / hexamethylene adipamide copolymer (nylon-6)
/ 6,6), caprolactam / hexamethylene adipamide / hexamethylene sebacamide copolymer (nylon-6
/ 6,6 / 6,12) and other aliphatic polyamide copolymers;
Aromatic polyamides such as polymethaxylylene adipamide (MX-nylon) and hexamethylene terephthalamide / hexamethylene isophthalamide copolymer (nylon-6T / 6I) can be mentioned. These polyamide resins can be used alone or in combination of two or more.

Among these polyamide resins, polycaproamide (nylon-6) or polyhexamethylene adipamide (nylon-6,6) is preferred.

Examples of the polyvinyl chloride resin (A3) used in the present invention include homopolymers of vinyl chloride or vinylidene chloride, and copolymers with vinyl acetate, maleic acid derivatives, higher alkyl vinyl ethers and the like.

The polyacrylonitrile resin (A4) used in the present invention includes, in addition to acrylonitrile homopolymers, copolymers with acrylates and the like.

In the present invention, a heat stabilizer, an ultraviolet absorber, an antioxidant, a coloring agent, a filler, a plasticizer, a filler, and other resins (polyolefin, etc.) are used as long as the object of the present invention is not impaired. It can be previously blended with the gas barrier resin (A).

In the present invention, a thermoplastic resin (B) having a carbon-carbon double bond is used. Since the thermoplastic resin (B) has a carbon-carbon double bond in its molecule, it can efficiently react with oxygen and obtain an oxygen scavenging function (oxygen absorbing function). The carbon-carbon double bond includes a conjugated double bond but does not include a multiple bond contained in an aromatic ring.

The carbon-carbon double bond is preferably
It is contained in the thermoplastic resin (B) at a rate of 0.0001 eq / g or more. This double bond is more preferably
0.0005 eq / g or more, more preferably 0.00
It is contained at a rate of 1 eq / g or more, most preferably 0.002 eq / g or more. When the content of the carbon-carbon double bond is less than 0.0001 eq / g, the oxygen absorption rate may not be sufficient, and the oxygen scavenging effect of the composition of the present invention may not be sufficiently improved.

The molecular weight of the thermoplastic resin (B) is preferably from 1,000 to 300,000. Further, in consideration of the moldability and workability of the resin composition, the mechanical properties of the molded article obtained therefrom, and the dispersibility of the resin composition in the gas barrier resin (A), etc., more preferably 10,000 to 25,000.
0, most preferably in the range of 40,000 to 200,000.

If the molecular weight of the thermoplastic resin (B) is less than 1,000, the dispersibility in the gas barrier resin (A) decreases, and the transparency, gas barrier properties and oxygen scavenging performance decrease. When the molecular weight exceeds 300,000, the dispersibility in the gas barrier resin (A) is reduced, and the transparency, gas barrier properties and oxygen scavenging performance are reduced, and the processability of the resin composition is also deteriorated.

The carbon-carbon double bond of the thermoplastic resin (B) is generally derived from a diene compound, but is not limited thereto. Examples of the diene compound used in the synthesis of the thermoplastic resin (B) used in the present invention include:
Isoprene, butadiene, 2-ethylbutadiene, 2-
Butyl-butadiene and the like. As the diene compound, only one component may be used, or two components may be used simultaneously, and there is no particular limitation.

The carbon-carbon double bond of the thermoplastic resin (B) used in the present invention may be contained in the main chain or the side chain, but may be contained in the side chain. Is more preferred (i.e., the group having a carbon-carbon double bond in the side chain is larger) since the oxygen absorption rate is increased. For example, when isoprene or butadiene is used as a raw material for synthesizing the thermoplastic resin (B), the vinyl content of the resulting thermoplastic resin (B) is 10%.
It is preferably at least 20%, more preferably at least 20%, even more preferably at least 30%. The vinyl bond content refers to the ratio of units forming a vinyl bond (CH ₂ = CH-) (1,2 addition polymerized) among all diene-derived units in the polymer. The double bond existing after the polymerization may be partially reduced by hydrogen as long as the performance of the composition of the present invention is not hindered.

In order to increase the content of vinyl bonds to 10% or more, a Lewis base is used as a cocatalyst when a diene compound such as isoprene is polymerized. Examples of Lewis bases are dimethyl ether, diethyl ether, methyl ethyl ether, ethers such as tetrahydrofuran, ethylene glycol diethyl ether, glycol ethers such as ethylene glycol dimethyl ether,
Examples include tertiary amines such as N, N, N ', N'-tetramethylethylenediamine (TMEDA) and triethylenediamine, and ether-containing amines such as N-methylmorpholine and N-ethylmorpholine. The Lewis base is used in an amount of 0.1 to 400 parts by weight per 100 parts by weight of the initiator described below.

As the solvent, an inert organic solvent is used.
Particularly suitable are hydrocarbons having 6 to 12 carbon atoms, such as hexane, heptane, octane, decane and their cyclic analogues. Aromatic solvents such as toluene,
Benzene, xylene and the like are also suitable. The polymerization is usually -20
The reaction is performed in a temperature range of 〜80 ° C. for 1 to 50 hours.

The thermoplastic resin (B) thus obtained contains a large number of double bonds in the side chain and thus is easily oxidized, and is excellent in oxygen absorption performance.

Suitable thermoplastic resins (B) include, for example, resins having at least one of the units represented by the following structural formula (I) and having a number average molecular weight in the range of 1,000 to 500,000:

[0064]

Embedded image

Wherein R ₁ is an alkyl group having 1 to 10 carbon atoms, an aryl group, an alkylaryl group or an alkoxy group, and R ₂ and R ₃ are each a hydrogen atom and 1 to 10 carbon atoms. alkyl group, a substituted aryl group, an unsubstituted aryl group, -COOR _4, -OCOR _5, a cyano group or a halogen atom,, R ₄ and R ₅ are each independently an alkyl group having 1 to 10 carbon atoms, aryl Group, an alkylaryl group, or an alkoxy group] In the definition of the structural formula (I), the number of carbon atoms of the aryl group is preferably 6 to 10, and the number of carbon atoms of the alkyl aryl group is Preferably it is 7-11, and the number of carbon atoms of an alkoxy group is preferably 1-10. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group.
Examples of the aryl group include a phenyl group, examples of the alkylaryl group include a benzyl group, examples of the alkoxy group include a methoxy group and an ethoxy group, and examples of the halogen atom include a chlorine atom.

The structural formula (I) of the thermoplastic resin (B)
Has an alkyl group having 1 to 3 carbon atoms as R ₁ (especially when it has a structural unit obtained by polymerizing isoprene, 2-ethylbutadiene, and 2-butylbutadiene);
The thermoplastic resin (B) is easily oxidized and is preferred as an oxygen-absorbing resin. Among them, a structural unit obtained by polymerizing isoprene as a structural unit represented by the structural formula (I) with the thermoplastic resin (B) (that is, R ₁ in the structural formula (I))
Contains a methyl group and R ₂ and R ₃ are hydrogen atoms), since the double bond (vinyl bond) of this structural unit effectively reacts with oxygen, and especially the thermoplastic resin (B) is oxidized. Easy to absorb and excellent in oxygen absorption. Further, isoprene is easily available and easily polymerizes with other monomers, so that isoprene is also suitable from the viewpoint of the cost of synthesizing the thermoplastic resin (B).

The thermoplastic resin (B) used in the present invention
Is preferably a copolymer of an aromatic vinyl compound and a diene compound. When the thermoplastic resin (B) is a copolymer of an aromatic vinyl compound and a diene compound, a double bond derived from the diene compound easily reacts with oxygen, thereby improving oxygen barrier properties and oxygen scavenging effects. be able to. Further, by adjusting the copolymerization ratio of the aromatic vinyl compound and the diene compound, the moldability and workability of the thermoplastic resin (B) can be improved, and the hardness can be changed. By adjusting the copolymerization ratio of the aromatic vinyl compound and the diene compound, the refractive index of the obtained thermoplastic resin (B) can be adjusted. Therefore,
As described below, when the composition of the present invention contains the gas barrier resin (A), the difference between the refractive index of the gas barrier resin (A) and the refractive index of the thermoplastic resin (B) is reduced. As a result, a product having excellent transparency can be obtained.

The aromatic vinyl compound used in the synthesis of the thermoplastic resin (B) used in the present invention includes styrene, 1-vinylnaphthalene, 2-vinylnaphthalene, 3-vinylnaphthalene, 3-methylstyrene,
4-propylstyrene, 4-cyclohexylstyrene,
4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4- (phenylbutyl) styrene and the like. Among them, styrene is most preferred from the viewpoint of cost and ease of polymerization.

When the thermoplastic resin (B) is a copolymer of an aromatic vinyl compound and a diene compound, the copolymer may be a random copolymer, a block copolymer, a graft copolymer, or a copolymer thereof. May be used without any particular limitation. From the viewpoints of manufacturability, mechanical properties of the thermoplastic resin (B), ease of handling, and oxygen absorption rate, a block copolymer is preferable.

When the thermoplastic resin (B) is a block copolymer, its production method is not particularly limited, but it is preferable to use an anionic polymerization method. At this time, the number average molecular weight of the aromatic vinyl compound block is preferably 3
In the range of 100 to 100,000, more preferably 10
In the range of 00 to 50,000, more preferably 300
The range is from 0 to 50,000. When the molecular weight of the aromatic vinyl compound block is less than 300, the melt viscosity of the thermoplastic resin (B) is low, and the molding, processing, or handling of the resin composition may be poor. In addition, mechanical properties such as strength and elongation when formed into a molded article tend to decrease. Further, as described later, in a case where the thermoplastic resin (B) is dispersed in another resin such as the gas barrier resin (A), the dispersibility of the thermoplastic resin (B) is reduced,
As a result, oxygen scavenging performance may decrease. If the molecular weight of the aromatic vinyl compound block exceeds 100,000, the melt viscosity is high and the thermoplasticity is impaired, so that the moldability and processability of the resin composition is reduced. Further, since the dispersibility is also reduced as described above, the oxygen scavenging performance tends to be reduced as a result.

The block form of the block copolymer is A
(BA) _n and (AB) _n . Here, A represents a block composed of an aromatic vinyl compound, B represents a block composed of a diene compound, and n is an integer of 1 or more.

The thermoplastic resin (B) used in the present invention is preferably a binary block copolymer or a ternary block copolymer, and more preferably a ternary block copolymer. Among them, it is preferable that the block composed of the aromatic vinyl compound is a polystyrene block and the block composed of the diene compound is polyisoprene from the viewpoint of cost and ease of polymerization. In particular, when the thermoplastic resin (B) is a diblock copolymer composed of a polyisoprene block containing the structural formula (I) and a polystyrene block, the polymerization is easy, the handling is easy, the oxygen absorption rate and the cost are low. It is preferred in that respect.
When the thermoplastic resin (B) is a ternary block copolymer composed of a polystyrene block-a polyisoprene block containing a structural formula (I) -a polystyrene block, the polymerization is easy, the handling is easy, the oxygen absorption rate and the cost are high. In addition to the above points, it is more preferable because the mechanical properties are improved.

Further, the thermoplastic resin (B) in the present invention
Is the ta in the block derived from the diene compound
The main dispersion peak temperature of nδ is preferably in the range of −40 ° C. to 60 ° C. The main dispersion peak temperature of tan δ is -4
If the temperature is lower than 0 ° C., the oxygen absorption rate tends to be low, and the oxygen scavenging performance tends to decrease. When the main dispersion peak temperature of tan δ exceeds 60 ° C., the oxygen absorption rate at a low temperature becomes slow, and the oxygen scavenging performance tends to decrease. In consideration of the oxygen scavenging performance, the main dispersion peak temperature of tan δ in the block derived from the diene compound is from −20 ° C. to 4 ° C.
The temperature is more preferably in the range of 0 ° C, and even more preferably in the range of -10 ° C to 30 ° C.

The block copolymer of an aromatic vinyl compound and a diene compound can be obtained by the following various methods. A method of polymerizing an aromatic vinyl compound and a diene compound with an alkyllithium compound as an initiator and coupling with a coupling agent, or a method of sequentially polymerizing a diene compound and an aromatic vinyl compound with a dilithium compound as an initiator Is a typical example,
It is not limited to these. Examples of the alkyl lithium compound include an alkyl compound having 1 to 10 carbon atoms in the alkyl residue. Particularly, methyl lithium, ethyl lithium, benzyl lithium and butyl lithium are preferred.

As the coupling agent, dichloromethane,
Dibromomethane, dichloroethane, dibromoethane and the like are used. Examples of the dilithium compound include naphthalenedilithium, oligostilidilithium, dilithiohexylbenzene, and the like. The amount used is 0.01 to 0.01 parts by weight based on 100 parts by weight of all monomers used in the polymerization.
0.2 parts by weight and 0.04 to 0.8 parts by weight of the coupling agent are suitable.

The block copolymer is prepared by adding the reaction solution for polymerization to a poor solvent such as methanol and coagulating the mixture, followed by heating or drying under reduced pressure, or by dropping the polymerization reaction solution into boiling water and subjecting the solvent to azeotropic distillation. -It is obtained by heating or drying under reduced pressure after removal.

Since the thermoplastic resin (B) is susceptible to oxidation due to its structure, it is recommended to add an antioxidant in advance, for example, to prevent oxidation during storage.

Examples of the antioxidant include 2,5-di-t-butylhydroquinone, 2,6-di-t-butyl-p-cresol, and 4,4′-thiobis- (6-t-butylphenol. ), 2,2'-methylene-bis- (4-
Methyl-6-t-butylphenol), octadecyl-
3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate, 4,4'-thiobis- (6
-Tert-butylphenol), 2-tert-butyl-6
-(3-tert-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, pentaerythritol tetrakis (3-laurylthiopropionate), 2,6-di- (t-butyl) -4 -Methylphenol (BHT), 2,2'-methylenebis- (6
-T-butyl-p-cresol), triphenyl phosphite, tris- (nonylphenyl) phosphite, dilauryl thiodipropionate, and the like.

The optimum amount of the antioxidant to be added is determined in consideration of the type and content of the components in the composition, the purpose of use, storage conditions, and the like. In general, when a large amount of an antioxidant is contained, a reaction between oxygen which tends to pass through a resin composition containing the thermoplastic resin (B) and the thermoplastic resin (B) is hindered. Therefore, the oxygen barrier properties and the oxygen scavenging function of the composition of the present invention may not be sufficiently exhibited. On the other hand, if the antioxidant is not contained or its content is too small, the reaction with oxygen proceeds during the storage or melt processing of the thermoplastic resin (B), and the oxygen absorption performance is reduced during actual use. It may have dropped.

When the thermoplastic resin (B) is stored in an inert gas atmosphere, or when the resin composition is produced by melting and blending at a relatively low temperature or with a nitrogen seal, the amount of the antioxidant is May be less.

In the case where an oxidation catalyst composed of a transition metal salt (C) is added at the time of melt blending to promote oxidation, the thermoplastic resin (B) contains a certain amount of an antioxidant. However, a resin composition having good oxygen absorbing ability can be obtained. In such a case, the content of the antioxidant is preferably 0.01 to 1% by weight, and 0.02% by weight.
~ 0.5 wt% is more preferred. This antioxidant may be added to the thermoplastic resin (B) in advance, as described above, or each component of the resin composition of the present invention is mixed in the same manner as other general additives described below. May be added sometimes.

The first gas barrier resin composition of the present invention has an oxygen transmission rate of 500 ml · 20 μm / m ² · da.
It contains a gas barrier resin (A) having y · atm (20 ° C., 65% RH) or less, a thermoplastic resin having a carbon-carbon double bond (B), a transition metal salt (C), and an inorganic filler (D). . Furthermore, the oxygen transmission rate is 500 ml
It contains a gas barrier resin (A) having a m / m ² · day · atm (20 ° C., 65% RH) or less, a thermoplastic resin (B) having a carbon-carbon double bond, and an inorganic filler (D). In the second gas barrier resin composition of the present invention having an oxygen absorption rate of 0.01 ml / m ² · day or more, the addition of the transition metal salt (C) is not essential, but preferably the transition metal salt (C) It contains. This transition metal salt (C)
Preferably 1 to 5000 ppm, preferably 5 to 1000 ppm, more preferably 10 to 50 ppm in terms of metal element.
It is contained in the range of 0 ppm. Thereby, the oxygen oxidation reaction of the thermoplastic resin (B) can be promoted. For example, the thermoplastic resin (B) can efficiently react with oxygen present inside the packaging material obtained from the composition of the present invention and oxygen which is going to permeate the packaging material. As a result, the oxygen barrier properties and the oxygen scavenging action of the resin composition of the present invention are improved. However, when the content of the transition metal salt (C) exceeds 5,000 ppm in terms of a metal element, the thermal stability of the resin composition of the present invention is reduced, and generation of decomposition gas and generation of a gel substance become remarkable. From such a viewpoint, the content of the transition metal salt (C) is preferably in the above range.

The metal used for such a transition metal salt (C) is preferably selected from the first, second or third transition series of the periodic table. Suitable metals are manganese, iron,
Cobalt, nickel, copper, rhodium, titanium, chromium,
Vanadium and ruthenium include, but are not limited to. Preferred among these metals are iron, nickel, copper, manganese and cobalt, more preferably manganese and cobalt, and even more preferably cobalt.

Examples of the counter ion of the metal used in the transition metal salt (C) include anions derived from organic acids or chlorides. Organic acids include acetic acid, stearic acid, dimethyldithiocarbamic acid, palmitic acid, 2-ethylhexanoic acid, neodecanoic acid, linoleic acid, tollic acid, oleic acid, resin acid, capric acid, and naphthenic acid, It is not limited to this. Particularly preferred salts include cobalt 2-ethylhexanoate, cobalt neodecanoate and cobalt stearate. The metal salt may be a so-called ionomer having a polymeric counter ion.

Preferred examples of the inorganic filler (D) used in the present invention include, but are not limited to, mica, sericite, glass flake, and talc. These inorganic fillers can be used alone or in combination. Among these inorganic fillers, it is most preferable to use talc from the viewpoint of oxygen barrier properties.

The weight average aspect ratio (α) of the inorganic filler (D) used in the present invention is 3 or more, preferably 5 or more, and more preferably 10 or more. If it is less than 3, the effect of imparting oxygen barrier properties may be reduced.
The weight average aspect ratio (α) of the inorganic filler (D) in the present invention is obtained by using the formula (1) based on the weight average flake diameter l and the weight average flake thickness d of the inorganic filler measured by the following method. This is a calculated value. α = 1 / d (1) Weight average flake diameter l of the inorganic filler in the formula (1)
Classifies the powder with micro sieves or sieves with various openings, plots the results on a Rosin-Rammlar diagram, and passes the micro sieves or sieves through which 50% by weight of the total weight of the powders used for measurement pass. is a value corresponding to the eyes open l _50. That is, the weight average flake diameter l of the powder
Is defined by equation (2) or (3). l = l ₅₀ (in the case of micro sieve) (2) l = 2 ^0.5 l ₅₀ (in the case of sieve) (3) Here, the portion of the powder having a large particle size is classified by the sieve. The fine part is classified by a micro sieve.
On the other hand, the weight average flake thickness d of the inorganic filler is:
C. E. FIG. Capes et al. Reported a single-particle water surface membrane method {C. E. FIG. Capes and R.A. C. Colema
n. Ind. Eng. Chem. Fundam. , Vo
l. 12, No. 2, P. 124-126 (197
3) The occupied area S of the flake on the water surface measured by｝
Is a value calculated from the following equation (4) using d = W / {ρ (1-ε) · S} (4) where W is the weight of the powder used for measurement, ρ is the specific gravity of the powder,
(1- [epsilon]) is the occupancy when the powder is in the closest packed state on the water surface.

Further, in order to improve the affinity with the resin (A), it is preferable to treat the surface of the inorganic filler (D) with a surface treating agent (for example, a silane coupling agent).

The inorganic filler (D) used in the present invention preferably has an average particle size of 10 μm or less. The average particle diameter of the inorganic filler (D) is more preferably 8 μm or less, and still more preferably 6 μm or less. When the average particle diameter of the inorganic filler (D) exceeds 10 μm, the transparency of the molded article may be deteriorated.

The composition of the present invention may contain a thermoplastic resin (E) other than the gas barrier resin (A) and the thermoplastic resin (B) to the extent that the effects of the present invention are not impaired. Examples of the thermoplastic resin (E) include, but are not limited to, the following resins: ethylene homopolymer and ethylene copolymer (copolymer of ethylene and the following monomers: propylene, 1-butene) Α-olefins such as isobutene, 4-methyl-1-pentene, 1-hexene and 1-octene; unsaturated carboxylic acids such as itaconic acid, methacrylic acid, acrylic acid and maleic anhydride; Esters, their nitriles, their amides, their anhydrides; vinyl carboxylate esters such as vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl octanoate, vinyl dodecanoate, vinyl stearate, and vinyl arachidonate A vinylsilane compound such as vinyltrimethoxysilane; Sulfonic acid or its salts; alkylthiols; vinyl pyrrolidones and the like),
Propylene homopolymers and propylene copolymers (copolymers of propylene and the following monomers: α-olefins such as ethylene, 1-butene, isobutene, 4-methyl-1-pentene, 1-hexene, 1-octene; itaconic acid, Unsaturated carboxylic acids such as methacrylic acid, acrylic acid and maleic anhydride, salts thereof, partial or complete esters thereof, nitriles thereof, amides thereof, anhydrides thereof; vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl Carboxylic acid vinyl esters such as octanoate, vinyl dodecanoate, vinyl stearate and vinyl arachidonate; vinyl silane compounds such as vinyl trimethoxy silane; unsaturated sulfonic acids or salts thereof; alkyl thiols; vinyl pyrrolidones ), Poly 4-me Rupenten -1, polyolefins such as polybutene-1, polyethylene terephthalate, polybutylene terephthalate, polyesters such as polyethylene naphthalate; polystyrene, polycarbonate, polyacrylate and the like. The selection of the thermoplastic resin (E) depends on the structure and use of the molded article to be produced. Such selection factors are well known in structure and use,
Thereby, the thermoplastic resin (E) is selected.

When producing a composition containing the thermoplastic resin (E), it is preferable to consider the miscibility of the thermoplastic resin (E) with the gas barrier resin (A) and the thermoplastic resin (B). . The miscibility of these resins can affect gas barrier properties, cleanliness, effectiveness as an oxygen scavenger, mechanical properties, product texture, and the like.

In the gas barrier resin composition of the present invention, preferably, the gas barrier resin (A) is 45 to 9
8.9% by weight, 30 to 0.1% by weight of the thermoplastic resin (B), and 25 to 1% by weight of the inorganic filler (D). The transition metal salt (C) is preferably 1 to
It is contained at a rate of 10000 ppm, more preferably 1 to 5000 ppm.

The content of the gas barrier resin (A) contained in the gas barrier resin composition is more preferably 60 to
97.5% by weight, more preferably 70 to 96% by weight. The more preferable content of the thermoplastic resin (B) contained in the gas barrier resin composition is 1 to 20% by weight, and the more preferable range is 2 to 15% by weight. The more preferable range of the content ratio of the inorganic filler (D) contained in the gas barrier resin composition is 22.2.
5 to 1.5% by weight, and a more preferable range is 20 to 2%.
% By weight.

The content ratio of the gas barrier resin (A) is 45
When the amount is less than the weight percentage, the processability and the gas barrier property of oxygen gas or carbon dioxide gas in a molded article such as a multilayer container using the resin composition may be reduced. On the other hand, when the content ratio of the gas barrier resin (A) exceeds 98.9% by weight, the content ratio of the thermoplastic resin (B) decreases, so that the oxygen absorption rate decreases, and the oxygen gas barrier property and oxygen scavenging property are reduced. The castability tends to decrease.

In the resin composition of the present invention, the particles composed of the thermoplastic resin (B) are composed of particles other than the resin (B) (gas barrier resin (A) and, if necessary, thermoplastic resin (E)) and It is recommended that the composition be dispersed in a matrix containing various additives described below, if necessary. For example, the resin composition of the present invention comprises a gas barrier resin (A)
In the case of using a thermoplastic resin (B), it is recommended that particles of the thermoplastic resin (B) be dispersed in a matrix of the gas barrier resin (A). Various molded articles made of the composition in such a state have good transparency, gas barrier properties and oxygen scavenging properties. At this time, the dispersed particle diameter of the particles made of the thermoplastic resin (B) is preferably 10 μm or less. When the dispersed particle size exceeds 10 μm, the thermoplastic resin (B) and the thermoplastic resin (B)
In some cases, the area of the interface with other resins becomes smaller, the oxygen gas barrier properties decrease, and the oxygen scavenging performance may decrease. In light of oxygen scavenging properties, gas barrier properties, and transparency of molded articles such as multilayer containers using the resin composition, the dispersed thermoplastic resin (B) particles have an average particle diameter of preferably 5 μm or less, more preferably 2 μm. The following are more preferred.

[0095] The resin composition of the present invention contains various additives as necessary. Examples of such additives include antioxidants, plasticizers, heat stabilizers (melt stabilizers), photoinitiators, deodorants, ultraviolet absorbers, antistatic agents, lubricants, colorants, fillers, and desiccants. Fillers, pigments, dyes, processing aids, flame retardants, anti-fogging agents and other high molecular compounds, and these can be contained within a range that does not impair the effects of the present invention. .

Heat stabilizer (melt stabilizer) among the above additives
As a hydrotalcite compound, a metal salt of a higher aliphatic carboxylic acid (for example, calcium stearate,
One or more of magnesium stearate and the like are used. These compounds are used in an amount of 0.1% in the entire resin composition.
It is preferable to contain it in a proportion of from 01 to 1% by weight.

When the resin composition of the present invention contains a hydrotalcite compound, it is possible to prevent gels and fish eyes which occur with time in a layer made of the resin composition, and to provide a long-term operation stability. Can be further improved.

Further, when the resin composition contains a metal salt of a higher aliphatic carboxylic acid, gels and fish eyes generated over time can be prevented, and the long-term operation stability is further improved. be able to.

The metal salt of a higher aliphatic carboxylic acid is a metal salt of a higher fatty acid having 8 to 22 carbon atoms. 8 to 2 carbon atoms
2 higher fatty acids include lauric acid, stearic acid,
And myristic acid. Examples of the metal constituting the salt include sodium, potassium, magnesium, calcium, zinc, barium, aluminum and the like.
Of these, alkaline earth metals such as magnesium, calcium and barium are preferred.

Among the above additives, a photoinitiator is used for initiating or promoting oxygen scavenging in a layered product or a packaging film made of a resin composition.

If the oxygen absorbing composition of the present invention contains an antioxidant, it is also recommended that the composition further contain one or more photoinitiators. By irradiating such a composition with light at a desired time, the initiation of the reaction between the thermoplastic resin (B) and oxygen is promoted, and as a result, the composition can exhibit an oxygen scavenging function. Becomes

Examples of suitable photoinitiators include, but are not limited to, the following compounds: benzophenone,
o-methoxybenzophenone, acetophenone, o-methoxyacetophenone, acenaphthenequinone, methyl ethyl ketone, valerophenone, hexanophenone, α-
Phenylbutyrophenone, p-morpholinopropiophenone, dibenzosuberone, 4-morpholinobenzophenone, benzoin, benzoin methyl ether, 4-o-
Morpholinodeoxybenzoin, p-diacetylbenzene, 4-aminobenzophenone, 4'-methoxyacetophenone, α-tetralone, 9-acetylphenanthrene, 2-acetylphenanthrene, 10-thioxanthone, 3-acetylphenanthrene, 3-acetylindole, 9- Fluorenone, 1-indanone, 1,3,5-
Triacetylbenzene, thioxanthen-9-one, xanthen-9-one, 7-H-benz [de] anthracen-7-one, benzoin tetrahydropyranyl ether, 4,4'-bis- (dimethylamino) -benzophenone, 1'-acetonaphthone, 2'-acetonaphthone, acetonaphthone and 2,3-butanedione, benz [a] anthracene-7,12-dione, 2,2-dimethoxy-2-phenylacetophenone, α, α-diethoxyacetophenone, α , α-dibutoxyacetophenone and the like. Singlet oxygen generating photosensitizers such as rose bengal, methylene blue and tetraphenylporphyrin can also be used as photoinitiators. In addition to the monomer type photoinitiators described above, polymeric initiators can also be used, including poly- (ethylene carbon monoxide) and oligo- [2-hydroxy-2-methyl-
1- [4- (1-methylvinyl) -phenyl] -propanone] is included. In general, the use of a photoinitiator is preferred because a faster and more efficient initiation effect is obtained.

When a photoinitiator is included, exposure to radiation accelerates the initiation of the reaction between the thermoplastic resin (B) and oxygen. The amount of photoinitiator used will vary depending on various factors. The amount of the photoinitiator is appropriately determined according to the type of the thermoplastic resin (B) generally used, the wavelength and intensity of the radiation used, the nature and amount of the antioxidant used, and the type of the photoinitiator used. It is determined. The amount of the photoinitiator also depends on the form in which the resin composition of the present invention is used. For example, a molded article made of a composition containing a photoinitiator is a slightly opaque layered body, and when irradiated with radiation, a relatively large amount of initiator is required.

In general, when a photoinitiator is used, its amount is preferably in the range of 0.01 to 10% by weight of the whole composition.

The oxygen-absorbing composition of the present invention containing the photoinitiator is exposed to radiation at a desired time, thereby initiating oxygen scavenging of the composition. Exposure to radiation significantly reduces or eliminates the induction period of oxygen scavenging of the oxygen absorbing composition, initiates oxygen scavenging,
Alternatively, oxygen scavenging can be promoted. The induction period is a time period until the oxygen-absorbing composition sufficiently starts capturing oxygen.

The radiation used is, for example, actinic radiation, for example, about 200 to 750 nm (n
m), ultraviolet or visible light having a wavelength of preferably about 200 to 400 nm is useful. Since actinic radiation has a relatively long wavelength, it is preferable from the viewpoints of cost, effects on the human body, and the like. In the case of exposure to radiation, the oxygen-absorbing composition is added in an amount of at least 0.1 per gram of the thermoplastic resin (B) contained in the composition.
Exposure to joules is preferred. Typical amounts of exposure range from 10 to 100 joules per gram of thermoplastic resin (B). The radiation may also be an electron beam at a dose of about 0.2 to 20 megarads, preferably about 1 to 10 megarads. Other radiation sources include ionizing radiation, such as gamma rays, x-rays, and corona discharges. Radiation exposure is preferably performed in the presence of oxygen.
The duration of the exposure will vary depending on various factors. Factors include the amount and type of photoinitiator present, the shape of the article to be exposed (eg, layer thickness), the amount of any antioxidants present, and the wavelength and intensity of the radiation source. Including, but not limited to.

The exposure of the resin composition of the present invention containing the above-mentioned photoinitiator to radiation may be carried out after preparing the composition into a desired molded article or article, or during the preparation. . For example, if the composition of the present invention is used for packaging oxygen-sensitive products, the exposure to radiation may be immediately before, during, or after packaging. However,
Radiation exposure needs to be prior to use of the article or article as an oxygen scavenger. For maximally uniform irradiation, the exposure should take place during a processing step in which the molded article or article is, for example, in the form of a flat sheet.

Of the above additives, deodorants (or deodorants and adsorbents; hereinafter, these are referred to as deodorants) are:
The resin composition of the present invention is used to reduce odor due to low-molecular by-products generated during scavenging of oxygen.

Examples of suitable deodorants include, but are not particularly limited to, zinc compounds, aluminum compounds, silicon compounds, iron (II) compounds, organic acids, iron (II) compound-organic acid compositions, and the like. Is raised. These may be used alone, or may be a mixture of multiple types or a double salt.

Examples of the zinc compound include zinc silicate, zinc oxide, zinc sulfate, zinc chloride, zinc phosphate, zinc nitrate,
Zinc carbonate, zinc acetate, zinc oxalate, zinc citrate, zinc fumarate, zinc formate and the like.

Examples of the aluminum compound include aluminum sulfate, aluminum phosphate, aluminum silicate, potassium aluminum sulfate and the like.

Examples of the silicon compound include silicon phosphate compounds such as silicon dioxide, silicon orthophosphate, silicon pyrophosphate-I type and silicon pyrophosphate-II type, and activated silica gel.

As the iron (II) compound, any iron compound can be used as long as it forms divalent iron ions.
Examples are ferrous sulfate, ferrous chloride, ferrous nitrate, ferrous bromide, ferrous iodide and other inorganic iron (II) salts, ferrous gallate, ferrous malate, Iron (I) such as ferrous fumarate
I) Organic salts, of which ferrous sulfate and ferrous chloride are preferred.

A composition (mixture or double salt) containing a zinc compound and a silicon compound is also preferably used. Specific examples of this composition include zinc silicate having a weight ratio of zinc oxide to silicon dioxide in the range of 1: 5 to 5: 1 and having a mostly amorphous structure. Preferred are substantially amorphous particles. The ratio of zinc oxide to silicon dioxide is preferably in the range from 1: 4 to 4: 1, more preferably in the range from 1: 3 to 3: 1.

A composition of a zinc compound and an aluminum compound is also preferably used. As a specific example of this, a mixture of zinc oxide and / or zinc carbonate, and aluminum sulfate and / or potassium aluminum sulfate is preferable. Preferably 30 to
It is mixed at a ratio of 300 parts by weight.

As the organic acids, organic acids having 8 or more carbon atoms, such as aliphatic monocarboxylic acids, aliphatic polycarboxylic acids, aromatic monocarboxylic acids, and aromatic polycarboxylic acids are preferable, and aromatic carboxylic acids are particularly preferable. . Examples of aromatic polycarboxylic acids include phthalic acid, terephthalic acid, isophthalic acid, trimellitic acid, 1,2,3-benzenetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, pyromellitic acid, benzenehexacarboxylic acid, naphthalene Dicarboxylic acid, naphthalene tricarboxylic acid, naphthalene tetracarboxylic acid, diphenyl tetracarboxylic acid, diphenyl ether tetracarboxylic acid, azobenzene tetracarboxylic acid or anhydrides thereof, among which benzene tricarboxylic acid, especially trimellitic acid Is preferred.

Iron (II) Compound--As the iron (II) compound used in the organic acid composition, any compound can be used as long as it is a compound which dissolves in water to form a divalent iron ion as described above. Can be used. For example, ferrous (II) inorganic salts such as ferrous sulfate, ferrous chloride, ferrous nitrate, ferrous bromide, and ferrous iodide, ferrous gallate, ferrous malate, and fumaric acid Organic salts of iron (II) such as ferrous acid may be mentioned, among which ferrous sulfate and ferrous chloride are preferred.

The organic acid used in the iron (II) compound-organic acid composition may be any water-soluble organic acid. Examples thereof include ascorbic acids such as ascorbic acid, isoascorbic acid and metal salts thereof, and citric acid. Acid, isocitric acid,
Examples thereof include carboxylic acids such as lactic acid, tartaric acid, and malic acid, and among them, L-ascorbic acid is preferable.

The iron (II) compound-organic acid composition to be used is preferably bound to each other, for example, by spray-drying an aqueous solution in which both components are once mixed and dissolved.
It can be prepared by drying and powdering by freeze-drying or the like. Iron (I
I) The component ratio of the compound to the organic acid is 1: 0.01 by weight.
１ ： 1: 1.0, more preferably 1: 1.
It is in the range of 0.02-1: 0.80. When the organic acid component is an ascorbic acid, the weight ratio of the iron (II) compound to the organic acid is preferably in the range of 1: 0.02 to 1: 0.30, more preferably 1: 0.02 to 1 : 0.13,
Particularly preferably, it is in the range of 1: 0.05 to 1: 0.13. In the present invention, two or more iron (II) compounds or two or more organic acids may be used in combination. Further, it is preferable to add 2 to 20% by weight of alum as a stabilizer for the deodorizing function to the total amount of the iron (II) compound and the organic acid to the iron (II) compound-organic acid composition. The alum is not particularly limited, but potash alum, ammonia alum, and sodium alum are preferred.

Further, as other deodorants, a composition in which a metal compound such as a composition comprising a zinc compound and a polycarboxylic acid is stabilized, a biological enzyme model compound such as an iron (II) -phthalocyanine derivative, a drill, Magnesium silicate clay minerals such as holly, mokusei, tsuwabuki, butterbur, lilac, sapwood, chestnut, alder, etc. Activated humic acid, activated alumina,
Activated carbon can also be used. Also, a porous adsorbent can be used.

Among the above-mentioned deodorants, zinc compounds such as zinc oxide and zinc sulfate, silicon compounds such as silicon dioxide and silicon orthophosphate, aluminum compounds such as aluminum sulfate and aluminum potassium sulfate, compositions containing zinc compounds and silicon compounds , A composition containing a zinc compound and an aluminum compound, and an organic acid, iron (I)
I) Compound-organic acid compositions are particularly preferred.

Among these deodorants, zinc silicate, a composition of zinc oxide and alum are preferable as a deodorant which can be preferably used in the resin composition of the present invention.

When the present invention has a multilayer structure such as a multilayer container, the deodorant is contained in the multilayer structure in various forms. As described later, it can be contained in a layer made of the resin composition or a layer other than this layer. In the multilayer structure of the present invention, when an adhesive resin layer is provided between the composition layer and another thermoplastic resin layer, a deodorant can be contained in the adhesive resin layer. The deodorant may be blended in only one of these layers or, if necessary, in two or more layers. The content of the deodorant is 0.1% by weight or more, preferably 0.2 to 50% by weight, more preferably 0.5 to 10% by weight based on the total weight of the layer (such as a resin layer) to be mixed.

The gas barrier resin composition of the present invention has various excellent properties. The second resin composition of the present invention comprises:
As described above, the oxygen absorption rate is 0.01 ml / m ²
-It is day or more. Further, the first resin composition of the present invention preferably has an oxygen absorption rate of 0.01 ml / m ² · day or more. The oxygen absorption rate is 0.0
It is more preferably at least 5 ml / m ² · day,
More preferably, it is 0.1 ml / m ² · day or more. When the oxygen absorption rate is less than 0.01 ml / m ² · day, the molded article such as a multilayer container molded using the resin composition of the present invention does not have sufficient oxygen barrier properties and has an oxygen scavenging effect. Is often not enough.

The oxygen absorption rate is the volume of oxygen absorbed by the film per unit surface area per unit time when the film of the resin composition is left in a fixed volume of air. A specific measuring method will be described in Examples described later.

The preferred melt flow rate (MFR) in the resin composition of the present invention (210 ° C., under a load of 2160 g, based on JIS K7210) is from 0.1 to 100 g.
/ 10 min, more preferably 0.5 to 50 g / 10 min, even more preferably 1 to 30 g / 10 min. When the melt flow rate of the resin composition of the present invention is out of the range of 0.1 to 100 g / 10 minutes, workability at the time of performing melt molding often deteriorates.

The gas barrier resin composition or resin of the present invention is formed into various molded products depending on the purpose.

The method of mixing and molding each component of the resin composition of the present invention is not particularly limited. The order of mixing the components is not particularly limited. For example, when a molded article is prepared by blending a gas barrier resin (A), a thermoplastic resin (B), a transition metal salt (C), and an inorganic filler (D), these components may be mixed at the same time. Alternatively, after preparing a blend of the thermoplastic resin (B) and the transition metal salt (C), the mixture may be mixed with the gas barrier resin (A) and further mixed with the inorganic filler (D).

Each of the components of the composition may be melt-blended and formed into pellets and then subjected to molding, or may be dry-blended and directly subjected to molding.

Means for blending and kneading the above components include a method of dissolving each resin component using a solvent, mixing and evaporating the solvent, and a method of melting and mixing at a temperature in the range of 50 ° C. to 300 ° C. Smelting method (melt blending method). The melt compounding method is preferred from the viewpoint of the simplicity of the process and the cost, but is not particularly limited. Examples of the means used for melt blending include a ribbon blender, a high-speed mixer, a co-kneader, a mixing roll, an extruder, a Banbury mixer, an intensive mixer and the like.

For example, each component of the composition of the present invention is kneaded with a Banbury mixer, a single-screw or twin-screw extruder, pelletized, and then subjected to melt molding. In order to prevent the oxidation of the thermoplastic resin (B) from proceeding during the blending operation, it is desirable to extrude at a low temperature by sealing the hopper port with nitrogen. Further, it is preferable to use an extruder having a high degree of kneading and to disperse each component finely and uniformly, in order to improve oxygen absorption performance and transparency and to prevent generation and mixing of gels and butter.

The kneading operation is important so that each component in the resin composition is well dispersed. As a kneader for obtaining a composition having a high degree of dispersion, a continuous kneader such as a continuous intensive mixer or a kneading type twin screw extruder (in the same direction or a different direction) is most suitable. And a batch-type kneader such as an intensive mixer or a pressure kneader. As another continuous kneading device, a device using a rotating disk having a grinding mechanism such as a stone mill, for example, a KCK manufactured by KCK Co., Ltd.
A CK kneading extruder can also be used. Among those usually used as a kneader, a single-screw extruder provided with a kneading section (Dalmage, CTM, etc.) or a simple kneader such as a Brabender mixer can be mentioned.

Among these, the most preferred one for the purpose of the present invention is a continuous intensive mixer. As a commercially available model, Farrel
FCM, Japan Steel Works CIM or Co., Ltd.
There are Kobe Steel's KCM, LCM and ACM.
In practice, it is preferable to employ a device that has a single screw extruder below these kneaders and that simultaneously performs kneading and extrusion pelletization. Also, a twin-screw kneading extruder having a kneading disk or a kneading rotor, for example, TEX, Werner & Pfleiderer manufactured by Japan Steel Works, Ltd.
ZSK manufactured by Toshiba Machine Co., Ltd., PCM manufactured by Ikegai Iron Works Co., Ltd., etc. are also used for the purpose of kneading in the present invention.

In using these continuous kneaders, the shapes of the rotor and the disk play an important role.
In particular, the gap (chip clearance) between the mixing chamber and the rotor chip or disk chip is important.
If the composition is too narrow or too wide, a composition having good dispersibility cannot be obtained. The optimum chip clearance is 1 to 5 mm.

The number of rotations of the kneading machine rotor is 100 to 12
A range of 00 rpm, preferably 150 to 1000 rpm, and more preferably 200 to 800 rpm is employed. The inner diameter (D) of the kneader chamber is 30 mm or more, preferably 50 to 400 mm. The ratio L / D to the chamber length (L) of the kneader is preferably 4 to 30. Also, one kneader may be used, or two or more kneaders may be used in combination.

The longer the kneading time, the better the results. However, the kneading time is in the range of 10 to 600 seconds, preferably 15 to 200 seconds, from the viewpoint of preventing oxidation of the thermoplastic resin (B) or economical efficiency. Is 15 to 150 seconds.

The resin composition of the present invention is formed into various molded products, for example, films, sheets, containers and other packaging materials, oxygen absorbers of various shapes, etc. by appropriately employing the various molding methods described above. be able to.

For example, it can be formed into a film, sheet, pipe or the like by melt extrusion molding, into a container shape by injection molding, or into a bottle-like hollow container by hollow molding. Preferable examples of the hollow molding include extrusion hollow molding, in which a parison is formed by extrusion molding, and blow molding of the parison, and injection hollow molding, in which a preform is formed by injection molding and blown and molded. Although illustrated as an aspect, it is not limited to these.

In the present invention, the molded article obtained by the above-mentioned molding may be a single layer, but if it is used as a laminate with a layer composed of other various resins, multi-function can be imparted. Is more preferable. When the resin composition of the present invention is used in a single layer, the oxygen barrier properties may be reduced by the contents or moisture of the outside air, and the mechanical strength may not be sufficient. To compensate for this, it is preferable to laminate a layer having a water vapor barrier property or a layer having high mechanical strength on the side where much moisture exists.

In the present invention, by covering the outside of the resin composition layer with another resin layer, the rate of intrusion of oxygen from the outside can be suppressed, and the oxygen absorbing function of the resin composition is maintained for a long time. From the viewpoint that it can be maintained, it is preferable to adopt a multilayer structure.

[0141] Of the containers having a multilayer structure, the embodiment in which the innermost layer of the container is formed of the resin composition of the present invention is preferable from the viewpoint that the oxygen scavenging function in the container is promptly exhibited.

As a specific layer configuration of the multilayer structure, a layer composed of a resin other than the thermoplastic resin (B), metal, paper, woven or non-woven fabric, etc. is a layer A, the thermoplastic resin (B) or a thermoplastic resin (B). A resin composition layer containing a plastic resin (B) as a B layer,
When the adhesive resin layer is a C layer, A / B, A / B / A, A
/ C / B, A / C / B / C / A, A / B / A / B / A,
Layer configurations such as A / C / B / C / A / C / B / C / A are exemplified, however, it is not limited to adding the other layers to these layers at all, and limited to the above examples. is not. When a plurality of layers made of another resin are provided, they may be of different types or the same. Further, a layer using a collected resin made of scrap such as trim generated at the time of molding may be separately provided, or the collected resin may be blended with a layer made of another resin. Although there is no particular limitation on the thickness configuration of the multilayer structure, the thickness ratio of the B layer to the total layer thickness is preferably 2 to 20% in consideration of moldability, cost, and the like.

As a material for forming a resin layer to be laminated on a molded article of the gas barrier resin composition of the present invention, a thermoplastic resin is preferable from the viewpoint of processability and the like. Such thermoplastic resins include, but are not limited to, the following resins: ethylene homopolymers and ethylene copolymers (copolymers of ethylene and the following monomers: propylene, 1-butene, isobutene) , 4-methyl-1-pentene, 1-hexene, 1-octene and the like
-Olefins; unsaturated carboxylic acids such as itaconic acid, methacrylic acid, acrylic acid, maleic anhydride, and salts thereof;
Its partial or complete esters, its nitriles, its amides, its anhydrides; vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl octanoate,
Carboxylic acid vinyl esters such as vinyl dodecanoate, vinyl stearate, and vinyl arachidonate; vinyl silane compounds such as vinyl trimethoxy silane; unsaturated sulfonic acids or salts thereof; alkyl thiols; vinyl pyrrolidones, etc.), propylene homo Polymers and propylene copolymers (copolymers of propylene with the following monomers: ethylene, 1-butene, isobutene, 4
Α-olefins such as -methyl-1-pentene, 1-hexene and 1-octene; unsaturated carboxylic acids such as itaconic acid, methacrylic acid, acrylic acid and maleic anhydride, salts thereof, partial and complete esters thereof, and nitriles thereof Carboxylic acid vinyl esters such as vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl octanoate, vinyl dodecanoate, vinyl stearate and vinyl arachidonate; vinyl trimethoxy Vinylsilane compounds such as silane; unsaturated sulfonic acids or salts thereof; alkylthiols; vinylpyrrolidones, etc.), polyolefins such as poly-4-methylpentene-1 and polybutene-1; polyethylene terephthalate, polybutylene terephthalate, polyethylene naphate Polyesters such as rate; poly ε- caprolactam, polyhexamethylene adipamide, polyamide such as poly-m-xylylene adipamide; polyvinylidene chloride, polyvinyl chloride, polystyrene, polyacrylonitrile, polycarbonates, polyacrylates and the like. The layer laminated by such a thermoplastic resin may be unstretched or may be uniaxially or biaxially stretched or rolled.

Among these thermoplastic resins, polyolefins are preferred because they are excellent in moisture resistance, mechanical properties, economy, heat sealability and the like. Further, since polyester is excellent in mechanical properties, the utility of laminating with the resin composition of the present invention is great.

Examples of the material for forming the metal layer to be laminated with the resin composition of the present invention include steel and aluminum generally used for cans and the like.

In the present invention, an adhesive resin can be used for bonding the resin composition layer of the present invention to another resin layer. The adhesive resin is not particularly limited as long as it can bond the respective layers, but may be a polyurethane-based or polyester-based one-pack or two-pack curable adhesive, a two-pack curable adhesive, or an unsaturated carboxylic acid. An olefin polymer or copolymer obtained by copolymerizing or graft-modifying an acid or an anhydride thereof (maleic anhydride or the like) (carboxylic acid-modified polyolefin resin) is suitably used.

Among these, it is more preferable that the adhesive resin is a carboxylic acid-modified polyolefin resin from the viewpoint of the adhesion between the surface layer of polyolefin and the resin composition layer. Examples of such carboxylic acid-modified polyolefin resins include polyethylene @ low density polyethylene (LDPE) and linear low density polyethylene (LLDP).
E), very low density polyethylene (VLDPE)｝, polypropylene, copolymerized polypropylene, ethylene-vinyl acetate copolymer, ethylene- (meth) acrylate (methyl ester or ethyl ester) copolymer, etc. What was done.

Examples of a method for obtaining a multilayer structure include an extrusion lamination method, a dry lamination method, a solvent casting method, a co-injection molding method, and a co-extrusion molding method, but are not particularly limited. Coextrusion molding methods include coextrusion lamination, coextrusion sheet molding, coextrusion inflation molding,
Coextrusion blow molding and the like can be mentioned.

The sheet, film, parison, etc. of the multilayer structure thus obtained is reheated at a temperature not higher than the melting point of the contained resin, and is subjected to thermoforming methods such as drawing, roll stretching, pantograph stretching. A molded product stretched by uniaxial or biaxial stretching by the inflation stretching method, the blow molding method, or the like can also be obtained.

[0150] Molded articles such as containers using the resin composition of the present invention, particularly multilayer structures, are used for various purposes. Among them, the superiority of using the resin composition of the present invention, which is extremely excellent in gas barrier properties and excellent in oxygen scavenging properties, is greatly exerted when used as various packaging containers.
In particular, it is suitable as a packaging container for foods, pharmaceuticals, agricultural chemicals, etc., whose quality is likely to deteriorate due to the presence of oxygen. Further, the resin composition of the present invention is suitable for use as a packing (gasket) for a container, particularly as a gasket for a cap of a container. A cap provided with such a gasket has excellent gas barrier properties and oxygen scavenging properties.

Further, among the packaging containers, the following two embodiments can be cited as examples in which the use of the resin composition of the present invention is highly useful. That is,
One is a container comprising a multilayer film having a total layer thickness of not more than 300 μm, including a layer comprising the resin composition of the present invention, and the other comprising a layer comprising the resin composition of the present invention, and extrusion blow It is a multilayer container formed by a molding method. Hereinafter, these embodiments will be sequentially described.

Including a layer comprising the resin composition of the present invention,
A container made of a multilayer film having a total layer thickness of 300 μm or less is a flexible container made of a multilayer structure having a relatively small overall layer thickness, and is usually processed into a pouch or the like.

Although the thickness of the multilayer film is not particularly limited, it is preferably 300 μm or less because good flexibility is easily maintained. More preferably 250 μm or less, more preferably 200 μm
It is as follows. On the other hand, the lower limit of the thickness is not particularly limited, but considering the mechanical strength of the container,
It is preferably at least 10 μm, more preferably at least 20 μm, even more preferably at least 30 μm. Even in a packaging container made of a multilayer film having a layer thickness of 300 μm or less, by using the gas barrier resin composition of the present invention, good gas barrier properties can be imparted, and an excellent oxygen scavenging function is provided. , The long-term storage of the contents can be improved. From this viewpoint, the present invention is significant.

Although the layer constitution is not particularly limited,
A multilayer film can be obtained by multilayering the resin composition layer of the present invention and another thermoplastic resin layer by a method such as dry lamination or coextrusion lamination.

For dry lamination, non-stretched films, uniaxially stretched films, biaxially stretched films, and rolled films can be used. Among these, a biaxially oriented polypropylene film, a biaxially oriented polyethylene terephthalate film, and a biaxially oriented poly ε-caprolactam film are preferred from the viewpoint of strength.
Biaxially oriented polypropylene films are particularly preferred because of their good moisture resistance.

In order to seal the packaging container, it is preferable to provide a layer made of a heat-sealable resin on at least one outermost surface of the multilayer film constituting the packaging container. Examples of such a resin include polyolefins such as polyethylene and polypropylene.

After lamination, the multilayer film is reheated and stretched by uniaxial or biaxial stretching by a thermoforming method such as drawing, a roll stretching method, a pantograph stretching method, or an inflation stretching method. You can also get.

[0158] The multilayer film thus obtained is processed into a bag shape, and the contents can be filled into a packaging container. Since it is flexible and simple, and is excellent in gas barrier properties and oxygen scavenging properties, it is extremely useful for packaging of contents that are easily degraded by the presence of oxygen, particularly foods and the like.

Including a layer comprising the resin composition of the present invention,
The multilayer container formed by the extrusion blow molding method has excellent gas barrier properties and oxygen scavenging properties.

The method for producing a multilayer container by extrusion blow molding in the present invention includes the following methods. First, using a multi-layer extruder having at least two extruders, a thermoplastic resin and a gas barrier resin composition forming the inner and outer layers and, if necessary, an interlayer adhesive resin are supplied to separate extruders. Kneading and melt-extrusion separately, extruding each layer so that they are closely joined together inside the die for multilayer parison molding or outside immediately after discharge from the die, obtain a tubular multilayer parison, and then blow-mold this parison in the molten state A so-called direct blow molding method for obtaining a co-extruded multi-layer container. Also, after forming a multi-layer pipe by extrusion molding, cutting it to an appropriate length, then sealing one end and attaching a lid such as a cap to the other end to form a bottomed parison Also, a stretch blow molding method of reheating and blowing this is employed.

As the blow molding method, a known direct blow method or stretch blow method is appropriately selected according to the application. For example, in general, the direct blow method does not increase the mechanical strength because the degree of molecular orientation of the resin is low, but has good dimensional stability at high temperatures, and thus is suitable for applications requiring high-temperature sterilization. On the other hand, the stretch blow method is suitable for applications requiring pressure resistance and creep resistance, such as carbonated beverage containers.
When molding a multilayer molded container by the direct blow method, it is preferable to use a polypropylene-based resin as the thermoplastic resin for forming the inner and outer layers. It is preferable to use a saturated polyester resin to be formed.

The resin composition of the present invention is previously melt-blended with a gas barrier resin (A), a thermoplastic resin (B), an inorganic filler (D), and, if necessary, a transition metal salt (C) to form pellets. May be supplied to a molding machine. Alternatively, the dry-blended materials may be supplied to a molding machine.

In the present invention, the total thickness of the container body of the blow container is generally 100 to 2000 μm, preferably 15 to 2000 μm.
It is 0 to 1000 μm, and can be properly used depending on the application. At this time, the total thickness of the resin composition layer of the present invention is 2 to
It is preferably in the range of 200 μm,
More preferably, it is within the range of m.

A multilayer container including a layer made of the gas-barrier thermoplastic resin composition of the present invention and formed by extrusion blow molding has extremely excellent gas barrier properties and oxygen scavenging properties. Therefore, it is useful for packaging of contents that are easily degraded due to the presence of oxygen, for example, foods, pharmaceuticals, and the like.

[0165]

EXAMPLES The present invention will be specifically described below with reference to examples and the like, but the present invention is not limited thereto. The analysis and evaluation in the following examples were performed as follows.

(1) Polyvinyl alcohol resin (A
Ethylene content and saponification degree of 1): The ethylene content and saponification degree of the polyvinyl alcohol-based resin (A1) were determined using 1H-deuterated dimethyl sulfoxide as a solvent.
NMR (nuclear magnetic resonance) spectrum ("JN" manufactured by JEOL Ltd.
M-GX-500 type ").

(2) Polyvinyl alcohol resin (A
Phosphate content in 1): The phosphate content was obtained as a phosphate ion (PO ₄ ³⁻ ) content according to the method described below. Dried polyvinyl alcohol resin 1 as a sample
0 g was added to 50 ml of 0.01N hydrochloric acid aqueous solution, and 9 g
Stirred at 5 ° C. for 6 hours. The aqueous solution after stirring was quantitatively analyzed using ion chromatography to obtain a phosphate ion content. The chromatography column used was CIS-A23 manufactured by Yokogawa Electric Corporation, and the eluent was an aqueous solution containing 2.5 mM sodium carbonate and 1.0 mM sodium hydrogen carbonate. Note that a calibration curve prepared with a phosphoric acid aqueous solution was used for the quantification.

(3) Polyvinyl alcohol resin (A
Content of Na ion, K ion and Mg ion in 1): 10 g of a dry chip as a sample was put into 50 ml of a 0.01 N hydrochloric acid aqueous solution, and stirred at 95 ° C for 6 hours. The aqueous solution after stirring was quantitatively analyzed using ion chromatography, and the amounts of Na ions, K ions, and Mg ions were quantified. The chromatography column is
ICS-C25 manufactured by Yokogawa Electric Corporation was used, and the eluent was an aqueous solution containing 5.0 mM tartaric acid and 1.0 mM 2,6-pyridinedicarboxylic acid. In the determination, a calibration curve prepared with an aqueous solution of sodium chloride, potassium chloride and magnesium chloride was used. From the amounts of Na ion, K ion and Mg ion thus obtained, the amounts of alkali metal salt and alkaline earth metal salt in the dried chip were obtained in terms of metal.

(4) Styrene content, vinyl bond content, and carbon-carbon double bond content of the thermoplastic resin (B): 1H-NMR (nuclear magnetic resonance) spectrum using heavy chloroform as a solvent (JEOL) "JNM-GX-50"
Thermoplastic resin (B) was measured according to “type 0”), and the structure of the resin was identified. Thereby, the content was calculated.

Here, the styrene content is the ratio (mol%) of styrene in all the monomers constituting the resin, and the vinyl bond content is the content of all the diene monomers in the diene block. Of those that formed vinyl bonds in (%)
Say. The content of the carbon-carbon double bond was determined by calculating the number of moles (eq / g) of the double bond contained in 1 g of the resin.

(5) Main dispersion peak temperature of tan δ in a block derived from a resin diene compound: Extrusion molding of a resin or a resin composition to be measured and a thickness of 20 μm.
m of unstretched film was obtained. Using the obtained film, RHEOLOGY Co. , LTD “DVE R
HEOSSPECTORER DVE-V4 "
Frequency 11 Hz, displacement amplitude 10 μm, distance between chucks 2
0 mm, width 5 mm, measurement temperature range -150 ° C to 150
The main dispersion peak temperature of tan δ in the block derived from the resin diene compound was measured at a temperature of 3 ° C. and a temperature rising rate of 3 ° C./min.

(6) Melt flow rate: Measured using a melt indexer L244 (manufactured by Takara Kogyo Co., Ltd.). Specifically, a sample resin or a resin composition chip is filled into a cylinder having an inner diameter of 9.55 mm and a length of 162 mm and melted at 190 ° C. or 210 ° C. 2160 g, diameter 9.
The load was evenly applied with a 48 mm plunger.
The flow rate (g / 10 minutes) of the resin extruded from the orifice having a diameter of 2.1 mm provided in the center of the cylinder was measured,
This was taken as the melt flow rate.

(7) Oxygen absorption rate of resin composition: Extrusion was performed using the resin composition to obtain a film having a thickness of 20 μm. The obtained single layer film 0.9m ² (0.2mx
4.5 m; surface area 1.8 m ² ) was wound into a roll 5 hours after film formation and placed in an Erlenmeyer flask with an internal volume of 375 ml filled with air at 20 ° C. and 65% RH. The air in the Erlenmeyer flask contains 21:79 by volume oxygen and nitrogen. The mouth of the Erlenmeyer flask was sealed with an epoxy resin using a multilayer sheet containing an aluminum layer, and then left at 20 ° C. The air inside 48 hours, 120 hours, and 216 hours after encapsulation was sampled with a syringe, and the oxygen concentration of this air was measured using gas chromatography. The pores vacated in the multilayer sheet at the time of measurement were closed each time using an epoxy resin. The measurement was obtained by calculating the amount of decrease in oxygen (oxygen absorption amount) from the volume ratio of oxygen and nitrogen obtained by gas chromatography. The amount of oxygen reduction in 7 days from 2 to 9 days after
The oxygen absorption rate (ml / m ² · day) of the resin composition was calculated by dividing the number of days by the surface area.

(8) Oxygen Permeation Rate of Gas Barrier Resin (A) The gas barrier resin (A) is extruded to a thickness of 20
A μm unstretched film was obtained. The resulting film is
The temperature and humidity were adjusted to 65 ° C.-65% RH, and an oxygen permeation amount measuring device (OX-TRAN-10 / 5, manufactured by Modern Control Co., Ltd.)
OA) was used to measure the amount of oxygen permeation. The extrusion temperature of the film was 210 ° C. for the EVOH resin.

(9) Oxygen permeation amount of multilayer film: A laminated film formed by laminating a resin composition layer and a stretched polypropylene film was used. In an atmosphere where the temperature and humidity were adjusted to 20 ° C. and 85% RH, the oxygen transmission amount of this film was measured using an oxygen transmission amount measuring device (OX-TRAN-10 / 50A, manufactured by Modern Control). The measurement was performed for a period of 1500 hours from 24 hours after the film formation.

Example 1 EVOH which is a polyvinyl alcohol resin (A1) as the gas barrier resin (A)
It was used. This EVOH has an ethylene content of 32 mol%, a saponification degree of 99.5%, and a melt flow rate (210
C.-2160 g load) 8.4 g / 10 min. When the phosphate group content and the Na, K, and Mg ion contents of this EVOH were measured, they were 100 ppm and 20 p, respectively.
pm, 60 ppm, and 20 ppm. The oxygen permeation rate was 0.4 ml · 20 μm / m ² · day · atm.

Next, a thermoplastic resin (B) to which an antioxidant was added was prepared by the following method.

In a stirred autoclave purged with dry nitrogen, 600 parts by volume of cyclohexane, N, N,
N ', N'-tetramethylethylenediamine (TMED
A) 0.16 parts by volume, n-BuLi0.0 as initiator
94 parts by volume were charged. After raising the temperature to 50 ° C., 4.25 parts by volume of a styrene monomer was fed and polymerized for 1.5 hours. Next, the temperature was lowered to 30 ° C., and then 120 parts by volume of isoprene was fed to carry out polymerization for 2.5 hours. Then, the temperature was raised again to 50 ° C., and 4.25 parts by volume of the styrene monomer was fed and polymerized for 1.5 hours.

The resulting reaction solution was treated with 2-oxidant as an antioxidant.
tert-butyl-6- (3-tert-butyl-2-
Hydroxy-5-methylbenzyl) -4-methylphenyl acrylate and pentaerythritol tetrakis (3-laurylthiopropionate) were added at 0.15 pp based on the total weight of styrene and isoprene, respectively.
hr. The reaction solution was poured into methanol to precipitate a triblock copolymer. This was dried and used as a thermoplastic resin (B) to which an antioxidant was added.

The number average molecular weight of the obtained triblock copolymer was 85,000, the molecular weight of the styrene block in the copolymer was 8,500, and the styrene content was 14 mol.
%, Vinyl bond content in the isoprene block is 55%
And the content of the structural unit represented by the structural formula (I) is 5
5%. The content of carbon-carbon double bonds in the obtained triblock copolymer was 0.014 eq / g, and the melt flow rate was 7.7 g / 10 minutes.
In the resin, 2-tert-butyl-6- (3-t
tert-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate 0.12% by weight
And 0.12% by weight of pentaerythritol tetrakis (3-laurylthiopropionate).
The main dispersion peak temperature of tan δ in a block derived from a diene compound of this resin was measured to be −3 ° C.

85 parts by weight of the EVOH, 5 parts by weight of the thermoplastic resin (B) prepared above, and talc having a particle diameter of 3 μm and a weight average aspect ratio of 15 as an inorganic filler (D) (manufactured by Fuji Talc Co., Ltd., LMS-400). 10 parts by weight and 0.2121 parts by weight of cobalt (II) stearate (0.0200 parts by weight as a cobalt atom) are dry blended, and a 30 mmφ twin screw extruder (Nippon Steel Works TEX Co., Ltd.)
Using -30SS-30CRW-2V), the mixture was extruded at 210 ° C. under the conditions of a screw rotation speed of 300 rpm and an extruded resin amount of 25 kg / hour, pelletized, and then dried under reduced pressure at 30 ° C. for 16 hours to obtain a resin composition pellet. Obtained. The melt flow rate of this resin composition (210 ° C.-2160
g load) was 8.7 g / 10 min. Observation of the fracture surface of the resin composition pellets with an electron microscope revealed that particles of about 1 μm of the above-mentioned triblock copolymer as the thermoplastic resin (B) were dispersed in a matrix composed of EVOH.

An extrusion temperature of 2 was obtained using the obtained resin composition.
Film extrusion was performed at 10 ° C. to obtain a film having a thickness of 20 μm. When the oxygen absorption amount of the film was measured, the result shown in FIG. 1 was obtained. 2 days later (48 hours) and 9
The oxygen absorption rate of the resin composition was 0.410 ml / m ² · day, calculated from the measurement result after 216 days (216 hours).

A stretched polypropylene film having a thickness of 20 μm (OP- # 20 U-1 manufactured by Tosello Co., Ltd.) was laminated on both sides of the film prepared using the above resin composition.
Urethane adhesive (manufactured by Toyo Morton, trade name: AD33)
5A and a curing agent (manufactured by Toyo Morton, trade name: Cat-1)
And a mixed solution of toluene and methyl ethyl ketone (weight ratio of 1: 1) with 0) to form a laminated film. Using this laminated film, the amount of oxygen transmission was measured over time, and the results shown in FIG. 2 were obtained.

(Comparative Example 1) EVOH used in Example 1
95 parts by weight of the thermoplastic resin (B) 5 obtained in Example 1
Parts by weight, and 0.212 cobalt (II) stearate
A resin composition was obtained in the same manner as in Example 1 using 1 part by weight (0.0200 part by weight as a cobalt atom). The melt flow rate of this resin composition (210 ° C.-2160
g load) was 9.5 g / 10 min. When the fracture surface of the obtained resin composition pellet was observed with an electron microscope,
The particles of about 1 μm of the triblock copolymer as the thermoplastic resin (B) were dispersed in a matrix composed of EVOH.

The obtained resin composition was subjected to film extrusion molding at an extrusion temperature of 210 ° C. to obtain a film having a thickness of 20 μm. When the oxygen absorption amount of the film was measured, the result shown in FIG. 1 was obtained. The oxygen absorption rate of the resin composition calculated from the measurement results after 2 days and 9 days was 0.521 ml /
m ² · day.

Next, a laminated film was produced in the same manner as in Example 1. Using this laminated film, the amount of oxygen transmission was measured over time, and the results shown in FIG. 2 were obtained.

(Comparative Example 2) EVOH used in Example 1
Using 90 parts by weight and 10 parts by weight of the inorganic filler (D) used in Example 1, film extrusion was performed at an extrusion temperature of 210 ° C. to obtain a film having a thickness of 20 μm. When the oxygen absorption amount of the film was measured, FIG.
Were obtained. The oxygen absorption rate of the EVOH resin was 0.000 m, calculated from the measurement results after 2 days and 9 days.
1 / m ² · day.

Next, a laminated film was produced in the same manner as in Example 1. Using this laminated film, the amount of oxygen transmission was measured over time, and the results shown in FIG. 2 were obtained.

Comparative Example 3 A film having a thickness of 20 μm was obtained by using the EVOH resin used in Example 1 alone and extruding a film at an extrusion temperature of 210 ° C. When the oxygen absorption amount of the film was measured, the result shown in FIG. 1 was obtained. The EV calculated from the measurement results after 2 days and 9 days
The oxygen absorption rate of the OH resin is 0.000 ml / m ² · da
y.

Next, a laminated film was produced in the same manner as in Example 1. Using this laminated film, the amount of oxygen transmission was measured over time, and the results shown in FIG. 2 were obtained.

The results of the above test are summarized in Table 1 below.

[0192]

[Table 1]

The resin composition of Example 1 having the structure of the present invention has an excellent oxygen absorption rate, and the multilayer blow-molded container having a layer made of the resin composition has an excellent oxygen barrier property. Indicated.

However, as is clear from FIG.
In the multilayer film of Comparative Example 1 containing no inorganic filler, the amount of oxygen permeation exceeded 0 in about 300 hours from the start of the measurement, whereas in the multilayer film of Example 1 of the present application, 40%.
For 0 hour or more, the state where the oxygen permeation amount was 0 could be maintained. The time required for the multilayer film of Comparative Example 1 to exhibit the same oxygen permeation amount as that of the multilayer film of Comparative Example 2 is about 1000 hours from the start of the measurement, as is clear from FIG. On the other hand, the multilayer film of Example 1 of the present application was
As shown in FIG. 2, the time required to show the same amount of oxygen permeation as that of the multilayer film was about 1400
It is apparent that the time, which is the time, and the time during which the amount of oxygen permeation can be suppressed, is greatly extended.

Example 2 The laminated film produced in Example 1 was punched out into a gasket shape to fit a polypropylene screw cap body having an outer diameter of 65 mm and a bottom thickness of 1.2 mm, and was attached to the screw cap body. Was. Then, the obtained cap with a gasket is supplied to a mold of a gasket molding machine for compression molding, and an ethylene-1-butene copolymer ("POLYBUTYLEN" manufactured by Shell Chemical Co., Ltd.) is supplied to the gasket molding machine for compression molding.
E 8240 ": 1-butene (99 mol% or more), ethylene (1 mol% or less) copolymer, density 0.908 g /
cm ³ , MFR = 2.0 g / 10 min (210 ° C., 216
A cap with a multilayer gasket was produced by supplying 0 g load)) and compression molding. At this time, the cylinder temperature of the compression molding machine was 245 ° C, the nozzle temperature was 235 ° C,
The mold temperature was adjusted to 30 ° C.

The sealing performance of the cap thus produced was evaluated as follows.

200 ml of water was put into a cylindrical blow bottle made of polyester having a content of 500 ml, a screw-type cap was attached, and the cap was tightened as shown in the following evaluation method. After that, the user held the bottle body by hand and shook it up and down 20 times. As a result, the state of liquid leakage was observed and evaluated and classified in the following four stages. A: Even if it is lightly tightened with a fingertip, there is no leakage at all. B: Leaking only by lightly tightening with a fingertip leaks the screw part of the cap. C: Leakage occurs when the fingertip is lightly tightened, and water scatters outside the cap, but does not leak when tightened strongly. D: It leaks even if tightened strongly. As a result of the evaluation, it was “A”, indicating good sealing properties.

[0198]

According to the present invention, a resin composition having excellent gas barrier properties, particularly excellent oxygen gas barrier properties and oxygen absorption properties, and having a longer oxygen absorption duration can be obtained. Such a resin composition can be prepared into a molded article of any shape. Molded articles prepared using these, for example, films and containers, are excellent in gas barrier properties and oxygen absorption.
Therefore, the resin composition or resin of the present invention, food,
It is useful as a container for storing articles, such as pharmaceuticals, which are easily deteriorated by oxygen.

A multilayer structure using the above resin composition, for example, a packaging material formed of a multilayer film is also suitably used because it has the above excellent performance. In particular, the total layer thickness is 300μ
m or less, or a multilayer container formed by extrusion blow molding is suitably used for containers requiring the above-described oxygen absorption or gas barrier properties.

[Brief description of the drawings]

FIG. 1 is a graph in which the amount of oxygen absorbed by a resin composition of Example 1 and a resin composition or a resin of Comparative Examples 1 to 3 is plotted against time.

FIG. 2 is a graph in which the oxygen permeation amounts of the multilayer films produced in Example 1 and Comparative Examples 1 to 3 are plotted against time.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/098 C08L 29/04 S C08L 29/04 B65D 30/02 // B65D 30/02 (C08L 101 / 12 (C08L 101/12 101: 02) 101: 02) B65D 1/00 BF term (reference) 3E033 BA30 BB01 BB08 CA16 FA03 GA03 3E064 BA60 BC08 EA17 EA18 FA03 GA01 4F100 AA01A AK01A AK07 AK69A AT00B BA02 CA23A GB15 GB16 GB16 JB16A JD03A JD14A YY00A 4J002 AA001 AA032 BB221 BC052 BD031 BD101 BE031 BG101 BL012 BL022 BP012 CL001 CL011 CL031 CL051 DD076 DJ047 DJ057 DL007 EG046 FA017 FA087 FD017 FD060 FD070 FD150 FD200 GG00

Claims (9)

[Claims] 1. An oxygen transmission rate of 500 ml · 20 μm /
Gas barrier resin (A) having m ² · day · atm (20 ° C., 65% RH) or less, thermoplastic resin (B) having a carbon-carbon double bond, transition metal salt (C), and inorganic filler (D) A gas barrier resin composition containing: 2. An oxygen absorption rate of 0.01 ml / m ² · d
The resin composition according to claim 1, which is at least ay. 3. An oxygen transmission rate of 500 ml · 20 μm /
Gas barrier resin composition containing gas barrier resin (A) having m ² · day · atm (20 ° C., 65% RH) or less, thermoplastic resin (B) having a carbon-carbon double bond, and inorganic filler (D) A product having an oxygen absorption rate of 0.
A gas barrier resin composition having a content of at least 01 ml / m ² · day. 4. The resin composition according to claim 1, wherein the thermoplastic resin (B) contains a carbon-carbon double bond at a rate of 0.0001 eq / g or more. 5. The gas-barrier resin (A) is an ethylene-vinyl alcohol copolymer having an ethylene content of 5 to 60 mol% and a saponification degree of 90% or more.
The resin composition according to any one of the above items. 6. The method according to claim 1, wherein the transition metal salt (C) is contained at a ratio of 1 to 5000 ppm in terms of a metal element.
6. The resin composition according to any one of items 2, 4, and 5. 7. The resin composition according to claim 1, wherein the weight average aspect ratio of the inorganic filler (D) is 3 or more. 8. The method according to claim 8, wherein the gas barrier resin (A) is 45 to 9
8.9% by weight of the thermoplastic resin (B) is 30 to 0.1%
The resin composition according to any one of claims 1 to 7, wherein the resin composition comprises 25% by weight and 25 to 1% by weight of the inorganic filler (D). 9. A multilayer structure having a layer comprising the gas barrier resin composition according to claim 1. Description: