JP7080151B2 - Gas barrier resin laminate and its manufacturing method - Google Patents

Description

The present invention relates to a gas barrier resin laminate containing an allyl alcohol copolymer which is used for packaging materials such as foods, pharmaceuticals and electronic materials and has a specific structure, and a method for producing the same.

Regarding packaging materials, in recent years, there has been an increasing demand for barrier properties that prevent the intrusion of gases such as oxygen and water vapor for the purpose of improving the quality of the contents, such as extending the expiration date of foods, maintaining freshness, and preventing deterioration of the quality of pharmaceutical products. There is. A metal-deposited film in which aluminum metal is vapor-deposited on the surface of a plastic film is a barrier film having excellent oxygen and steam barrier properties, but has a problem of being opaque and the contents cannot be visually recognized, and a transparent barrier film is required. ing.

As a transparent thin-film film, a transparent thin-film film in which a metal oxide such as alumina or silica is vapor-deposited on a plastic film such as a polyethylene terephthalate (PET) film has been developed. Although the oxygen and steam barrier properties of the transparent vapor-filmed film are inferior to those of the metal-film-deposited film, they have sufficient performance for packaging material use and are transparent so that the contents can be visually recognized. However, there is a problem that the metal oxide vapor-filmed film exhibiting oxygen and water vapor barrier properties is easily cracked, and the vapor-film vapor film is cracked due to an impact during transportation to generate pinholes and cracks, and the oxygen and water vapor barrier properties are easily deteriorated. was there. Further, since the metal oxide film is formed by vacuum deposition or sputtering, there is a problem that the manufacturing cost is high.

On the other hand, a coated type barrier film in which an oxygen barrier resin is coated on a plastic film having a high water vapor barrier property to form a gas barrier resin laminate has been conventionally known. As a result, a barrier film having oxygen and water vapor barrier properties can be obtained at a lower cost than the transparent vapor-deposited film while ensuring the flexibility and transparency (visibility of the contents) as the barrier film.

Conventionally, polyvinylidene chloride (PVDC) has been used as a material for an oxygen barrier resin layer, but there has been a problem of environmental impact such as generation of dioxins when incinerating and disposing of it. To solve this problem, polyvinyl alcohol (PVA) resin containing no chlorine is used. A barrier laminate can be obtained by applying an aqueous solution of PVA resin to a plastic film and drying it. However, since water having a large latent heat of vaporization is used as a solvent at this time, there is a problem that it is difficult to dry and the manufacturing cost increases.

Further, the PVA resin has a drawback that the oxygen barrier property is significantly lowered under the condition of high humidity, and therefore, there is a problem that it cannot be used for foods having high water activity.
Therefore, an ethylene-vinyl alcohol copolymer (EVOH resin) is known as a resin having a small decrease in oxygen barrier property under high humidity conditions. The EVOH resin can be dissolved in a mixed solvent of water and alcohol to be applied to a plastic film and dried in the same manner as the PVA resin to obtain a barrier laminate. However, since water is contained in the solvent as in the PVA resin, there is a problem that drying is delayed and the production cost tends to increase. Further, the EVOH resin has a problem that the stability of the solution is low and the quality of the coating film is not stable because it precipitates when the solution is stored or partially precipitates when the solution is dried after coating. Therefore, in the EVOH resin, the laminate is manufactured by coextrusion with other plastics such as polypropylene (PP) regardless of the coating.

However, when molding by coextrusion, an adhesive resin layer is required between the EVOH resin layer and another plastic layer, and for this reason, it is necessary to mold with a special molding device. As a result, there is a problem that the cost for molding increases.
As a gas barrier material whose barrier property does not deteriorate even under high humidity conditions, Patent Document 1 (Japanese Unexamined Patent Publication No. 10-330508) discloses a gas barrier material made of a metallic alcohol-based polymer. Further, Patent Document 2 (Japanese Unexamined Patent Publication No. 10-264318) discloses a laminate obtained by applying a solution of an allyl alcohol-based polymer to a substrate and drying it.
In these prior art documents, the metallyl alcohol-based polymer and the allyl alcohol-based polymer are obtained by radically polymerizing or anionicly polymerizing the corresponding acrylic acid or acrylic acid ester and then reducing it with a metal hydride or the like. It is said that. However, these polymerization methods have a problem that branching is likely to occur in the main chain and thermal deterioration is likely to occur starting from the branching. In addition, metal hydrides are generally expensive, and the manufacturing cost tends to increase, which is also a problem.

Patent Document 1 and Patent Document 2 disclose a laminate or a gas barrier material using an allyl alcohol-based resin, but the description of Examples is for a polymeryl alcohol or a polyallyl alcohol, or a co-formation of styrene and a metalyl alcohol. It is a polymer, and the copolymer with ethylene or propylene is not disclosed at all, the adhesion to the polyolefin resin is insufficient, and the use of an anchor coating agent is required to improve the adhesion, resulting in high manufacturing cost. It was the cause of the rise. Further, the glass transition point (Tg) of the specifically disclosed polymetallic alcohol, polyallyl alcohol, or a copolymer of styrene and metallic alcohol is high (Patent Document 1 is 45 to 95 ° C., Patent Document 2). 75 ° C), there was a problem of low flexibility.
Therefore, there has been a demand for a highly flexible transparent resin having an oxygen barrier property, which does not deteriorate the barrier property even under high humidity conditions, is easy to apply and dry, and has good adhesion to a polyolefin resin. ..

Japanese Unexamined Patent Publication No. 10-330508 Japanese Unexamined Patent Publication No. 10-264318

An object of the present invention is a gas barrier resin laminate having a resin containing an allyl alcohol copolymer which has a gas barrier property that can be used as a packaging material and whose gas barrier property does not decrease even under high humidity conditions as a gas barrier layer. Is to provide.

（式中、Ｒ¹は水素原子またはメチル基を表し、Ｒ²はハロゲン原子、水酸基、アルコキシ基、またはアミノ基で置換されていてもよい炭素原子数１～２０の炭化水素基を表す。ｌ、ｍ及びｎはそれぞれのモノマー構造単位のモル比を表す数値であり、ｎは０であってもよい。）
で示されるモノマー構造単位を含むアリルアルコール共重合体であって、（Ａ）一般式（１）、一般式（２）及び一般式（３）で示されるモノマー構造単位のモル比ｌ、ｍ及びｎが、次式：３０≦｛（ｍ＋ｎ）／（ｌ＋ｍ＋ｎ）｝×１００≦８０の関係を満足するアリルアルコール共重合体を含むガスバリア性樹脂層を有するガスバリア性樹脂積層体。
［２］ 前記アリルアルコール共重合体の（Ｂ）ガラス転移点が－７０℃以上かつ４０℃以下である前項１に記載のガスバリア性樹脂積層体。
［３］ 前記アリルアルコール共重合体の（Ｃ）重量平均分子量（Ｍｗ）が１０００以上かつ１００００００以下である前項１または２に記載のガスバリア性樹脂積層体。
［４］ 前記アリルアルコール共重合体の（Ｄ）主鎖を構成する炭素原子１０００個あたり、炭素原子数２以上の分岐が１個以下である前項１～３のいずれかに記載のガスバリア性樹脂積層体。
［５］ 前記アリルアルコール共重合体の（Ｅ）主鎖中に存在する炭素－炭素二重結合の数が２個以下である前項１～４のいずれかに記載のガスバリア性樹脂積層体。
［６］ 前記アリルアルコール共重合体が、一般式（１）及び一般式（２）で示されるモノマー構造単位のみを有する前項１～５のいずれかに記載のガスバリア性樹脂積層体。
［７］ 一般式（１）におけるＲ¹が水素原子である前項１～６のいずれかに記載のガスバリア性樹脂積層体。
［８］ Ｒ²が表す炭素原子数１～２０の炭化水素基が、炭素原子数１～２０のアルキル基または炭素数６～２０のアリール基である前項１～７のいずれかに記載のガスバリア性樹脂積層体。
［９］ プラスチックフィルムが、ポリエチレンフィルム、延伸または無延伸のポリプロピレンフィルム、ポリエチレンテレフタレートフィルム、ポリアミドフィルム、セロハンフィルム、及びポリシクロオレフィンから選択される少なくとも１種である前項１～８のいずれかに記載のガスバリア性樹脂積層体。
［１０］ プラスチックフィルムが透明蒸着フィルムである前項１～９のいずれかに記載のガスバリア性樹脂積層体。
［１１］ プラスチックフィルム層の間にガスバリア層を有する前項１～１０のいずれかに記載のガスバリア性樹脂積層体。
［１２］ アリルアルコール共重合体を溶媒に溶解した溶液を、プラスチックフィルムの表面に塗布し乾燥してガスバリア層を形成することを特徴とする前項１～１１のいずれかに記載のガスバリア性樹脂積層体の製造方法。
［１３］ 溶媒がアルコール類またはグリコールモノエーテル類を含む前項１２に記載のガスバリア性樹脂積層体の製造方法。
［１４］ コロナ処理、プラズマ処理、火炎処理、または易接着層コート処理のいずれかの表面処理を施したプラスチックフィルムを使用する前項１２または１３に記載のガス
［１５］ プラスチックフィルムとガスバリア性フィルムを共押出成形法によって成形することを特徴とする前項１～１１のいずれかに記載のガスバリア性樹脂積層体の製造方法。
［１６］ 前項１～１１のいずれかに記載のガスバリア性樹脂積層体を用いてなる包装用材料。 As a result of diligent studies to solve the above problems, the present inventors can solve the above problems by forming a laminate composed of a gas barrier resin layer containing an allyl alcohol copolymer having a specific structure. The present invention was completed.
That is, the present invention relates to the following gas barrier resin laminate, a method for producing the gas barrier resin laminate, and a packaging material.
[1] Plastic film layer, and general formula (1), general formula (2), and general formula (3).

(In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, or an amino group. , M and n are numerical values representing the molar ratio of each monomer structural unit, and n may be 0.)
It is an allyl alcohol copolymer containing the monomer structural unit represented by (A), and the molar ratio l, m and the monomer structural unit represented by the general formula (1), the general formula (2) and the general formula (3). A gas barrier resin laminate having a gas barrier resin layer containing an allyl alcohol copolymer in which n satisfies the relationship of the following formula: 30 ≦ {(m + n) / (l + m + n)} × 100 ≦ 80.
[2] The gas barrier resin laminate according to item 1 above, wherein the (B) glass transition point of the allyl alcohol copolymer is −70 ° C. or higher and 40 ° C. or lower.
[3] The gas barrier resin laminate according to item 1 or 2 above, wherein the (C) weight average molecular weight (Mw) of the allyl alcohol copolymer is 1000 or more and 1,000,000 or less.
[4] The gas barrier resin according to any one of the above items 1 to 3, wherein the number of branches having 2 or more carbon atoms is 1 or less per 1000 carbon atoms constituting the (D) main chain of the allyl alcohol copolymer. Laminated body.
[5] The gas barrier resin laminate according to any one of the above items 1 to 4, wherein the number of carbon-carbon double bonds present in the (E) main chain of the allyl alcohol copolymer is 2 or less.
[6] The gas barrier resin laminate according to any one of the above items 1 to 5, wherein the allyl alcohol copolymer has only the monomer structural units represented by the general formulas (1) and (2).
[7] The gas barrier resin laminate according to any one of the above items 1 to 6, wherein R ¹ in the general formula (1) is a hydrogen atom.
[8] The gas barrier according to any one of the above items 1 to 7, wherein the hydrocarbon group having 1 to 20 carbon atoms represented by R ² is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms. Sex resin laminate.
[9] The above item 1 to 8, wherein the plastic film is at least one selected from a polyethylene film, a stretched or unstretched polypropylene film, a polyethylene terephthalate film, a polyamide film, a cellophane film, and a polycycloolefin. Gas barrier resin laminate.
[10] The gas barrier resin laminate according to any one of items 1 to 9 above, wherein the plastic film is a transparent vapor-deposited film.
[11] The gas barrier resin laminate according to any one of items 1 to 10 above, which has a gas barrier layer between the plastic film layers.
[12] The gas barrier resin laminate according to any one of the above items 1 to 11, wherein a solution in which an allyl alcohol copolymer is dissolved in a solvent is applied to the surface of a plastic film and dried to form a gas barrier layer. How to make a body.
[13] The method for producing a gas barrier resin laminate according to item 12, wherein the solvent contains alcohols or glycol monoethers.
[14] The gas [15] plastic film and gas barrier film according to the preceding item 12 or 13, which uses a plastic film that has been subjected to any surface treatment of corona treatment, plasma treatment, flame treatment, or easy-adhesive layer coating treatment. The method for producing a gas barrier resin laminate according to any one of the above items 1 to 11, wherein the film is formed by a coextrusion molding method.
[16] A packaging material using the gas barrier resin laminate according to any one of the above items 1 to 11.

The gas barrier resin laminate of the present invention is useful as a gas barrier resin laminate for packaging materials having excellent transparency and high flexibility without lowering the barrier property even under high humidity conditions.

The gas barrier resin laminate of the present invention is a laminate composed of at least one gas barrier resin layer containing an allyl alcohol copolymer having a specific structure and at least one plastic film layer.
In the present invention, "film" is a concept including both "film" and "sheet" which are strictly distinguished by their thickness.

（式中、Ｒ¹は水素原子またはメチル基を表し、Ｒ²はハロゲン原子、水酸基、アルコキシ基、またはアミノ基で置換されていてもよい炭素原子数１～２０の炭化水素基を表す。ｌ、ｍ、及びｎはそれぞれのモノマー構造単位のモル比を表す数値であり、ｎは０であってもよい。）で示されるモノマー構造単位を有する共重合体であって、以下の要件（Ａ）を満たし、要件（Ｂ）～（Ｅ）を満たすことが好ましい。
（Ａ）一般式（１）、一般式（２）及び一般式（３）で示されるモノマー構造単位のモル比ｌ、ｍ、及びｎが、次式：３０≦｛（ｍ＋ｎ）／（ｌ＋ｍ＋ｎ）｝×１００≦８０の関係を満足する。
（Ｂ）ガラス転移点（Ｔｇ）が－７０℃以上４０℃以下である。
（Ｃ）重量平均分子量Ｍｗが１０００以上かつ１００００００以下である。
（Ｄ）主鎖を構成する炭素原子１０００個あたり、炭素原子数２以上の分岐が１個以下である。
（Ｅ）主鎖中に存在する炭素－炭素二重結合の数が２個以下である。 [Allyl alcohol copolymer]
The allyl alcohol copolymer for obtaining the gas barrier resin laminate of the present invention has the general formula (1), the general formula (2), and the general formula (3).

(In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom, a hydroxyl group, an alkoxy group or an amino group. , M, and n are numerical values representing the molar ratio of each monomer structural unit, and n may be 0), and the copolymer has the monomer structural unit represented by the following requirements (A). ), And the requirements (B) to (E) are preferably satisfied.
(A) The molar ratios l, m, and n of the monomer structural units represented by the general formulas (1), (2), and (3) are as follows: 30 ≦ {(m + n) / (l + m + n). } × 100 ≦ 80 is satisfied.
(B) The glass transition point (Tg) is −70 ° C. or higher and 40 ° C. or lower.
(C) The weight average molecular weight Mw is 1000 or more and 1,000,000 or less.
(D) The number of branches having 2 or more carbon atoms is 1 or less per 1000 carbon atoms constituting the main chain.
(E) The number of carbon-carbon double bonds present in the main chain is 2 or less.

The allyl alcohol copolymer for obtaining the gas barrier resin laminate of the present invention is basically composed of only the monomer structural units represented by the general formulas (1) and (2) (that is, n). = 0) is preferable. However, for the purpose of improving physical properties, the monomer structural unit represented by the general formula (3) may be contained.
In this case, in order not to impair the gas barrier property of the laminated body, it is represented by the general formula (3) with respect to the total number of the monomer structural units represented by the general formula (2) and the monomer structural units represented by the general formula (3). The ratio of the number of monomer structural units ({n / (m + n)} × 100) is preferably 5 mol% or less, more preferably 3 mol% or less, still more preferably 2 mol% or less.

[Monomer structural unit]
R ¹ in the general formula (1) represents a hydrogen atom or a methyl group. R ¹ is preferably a hydrogen atom.
R ² in the general formula (3) represents a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, or an amino group. As the hydrocarbon group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms is preferable. The aryl group also includes an aromatic ring to which an alkyl group is added. The halogen atom as the substituent is preferably a fluorine, chlorine or bromine atom, and more preferably a fluorine atom. As the alkoxy group as the substituent, an alkoxy group having 1 to 3 carbon atoms is preferable.

Specific examples of the hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, or an amino group represented by R ² include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, neopentyl group, n-hexyl group, trifluoromethyl group, trichloromethyl group, tribromomethyl group, pentafluoroethyl Group, pentachloroethyl group, pentabromoethyl group, phenyl group, 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 2,6-dimethylphenyl group, 2,4,6-trimethylphenyl group , 2-methoxyphenyl group, 3-methoxyphenyl group, 4-methoxyphenyl group, 2,3-dimethoxyphenyl group, 2,4-dimethoxyphenyl group, 2,5-dimethoxyphenyl group, 2,6-dimethoxyphenyl group , 2,4,6-trimethoxyphenyl group, 2-ethoxyphenyl group, 3-ethoxyphenyl group, 4-ethoxyphenyl group, 2,3-diethoxyphenyl group, 2,4-diethoxyphenyl group, 2, 5-Diethoxyphenyl group, 2,6-diethoxyphenyl group, 2,4,6-triethoxyphenyl group, 2-propoxyphenyl group, 3-propoxyphenyl group, 4-propoxyphenyl group, 2,3-di Propoxyphenyl group, 2,4-dipropoxyphenyl group, 2,5-dipropoxyphenyl group, 2,6-dipropoxyphenyl group, 2,4,6-tripropoxyphenyl group, 2-isopropoxyphenyl group, 3 -Isopropoxyphenyl group, 4-isopropoxyphenyl group, 2,3-diisopropoxyphenyl group, 2,4-diisopropoxyphenyl group, 2,5-diisopropoxyphenyl group, 2,6-diisopropoxy Phenyl group, 2,4,6-triisopropoxyphenyl group, 2-hydroxyphenyl group, 3-hydroxyphenyl group, 4-hydroxyphenyl group, 2,3-dihydroxyphenyl group, 2,4-dihydroxyphenyl group, 2 , 5-Dihydroxyphenyl group, 2,6-dihydroxyphenyl group, 2,4,6-trihydroxyphenyl group, hydroxymethyl group, 2-hydroxyethyl group, 2-hydroxy-n-propyl group, 3-hydroxy-n -Propyl group, pentafluorophenyl group, 2-trifluoromethylphenyl group, 3-trifluoromethylphenyl group, 4-trif Luolomethylphenyl group, 3,5-bis (trifluoromethyl) phenyl group, 2,3-bis (trifluoromethyl) phenyl group, 2,4-bis (trifluoromethyl) phenyl group, 3,4-bis Examples thereof include (trifluoromethyl) phenyl group, 2,4,6-tris (trifluoromethyl) phenyl and the like. Among these, a methyl group, an ethyl group, a phenyl group, a trifluoromethyl group and a trichloromethyl group are preferable, and a methyl group and a trifluoromethyl group are more preferable, from the viewpoint of the cost of the monomer as a raw material and industrial availability. ..

Further, in the allyl alcohol copolymer of the present invention, in order to improve the physical properties, a fourth monomer is copolymerized in addition to the monomer structural unit represented by the general formula (3) as long as the effect of the present invention is not impaired. May be.

The fourth monomer is not particularly limited, but aromatic vinyl compounds such as styrene, α-methylstyrene and divinylbenzene; 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene and the like. α-olefins; chain conjugated diene such as 1,3-butadiene and isoprene; vinyl ethers such as ethyl vinyl ether and propyl vinyl ether; acrylates such as methyl acrylate and 2-ethylhexyl acrylate; methacrylates such as methyl methacrylate and ethyl methacrylate. Classes; vinyl esters such as vinyl acetate and vinyl propionate; vinyl silanes such as trimethylvinylsilane and tert-butyldimethylvinylsilane; vinylsiloxanes such as trimethylvinyloxysilane and tert-butyldimethylvinyloxysilane; vinyl alcohol and metalylyl. Alcohol, 3-butene-1-ol, 4-penten-1-ol, 5-hexene-1-ol, 3-methyl-3-butene-1-ol, 4-methyl4-penten-1-ol, 5 -Alcohols having a vinyl group such as methyl-5-hexene-1-ol, 1-butene-3,4-diol; and the like can be mentioned. Further, when the fourth monomer is copolymerized, two or more of these may be used in combination.

In the allyl alcohol copolymer used in the laminate of the present invention, the copolymerization mode of each monomer structural unit can be any of random copolymerization, block copolymerization, and alternate copolymerization depending on the polymerization conditions.

Condition (A): Molar ratio of monomer structure unit The monomer structures of the general formulas (1), (2), and (3) of the allyl alcohol copolymer constituting the barrier layer in the laminate of the present invention. The molar ratios l, m, and n of the units satisfy the relationship of the following equation: 30 ≦ {(m + n) / (l + m + n)} × 100 ≦ 80.
Further, the following equation: preferably satisfies the relationship of 50 ≦ {(m + n / (l + m + n)} × 100 ≦ 80, and satisfies the relationship of the following equation: 60 ≦ {(m + n) / (l + m + n)} × 100 ≦ 80. It is more preferable to do.
When the mol% of (m + n) exceeds 30, gas barrier properties are exhibited, and when it is less than 80, the adhesion to the polyolefin-based plastic film becomes good.

Condition (B): Glass transition point (Tg)
The allyl alcohol copolymer constituting the barrier layer in the laminate of the present invention has a low glass transition point (Tg) and is flexible because it contains ethylene and / or propylene structural units represented by the general formula (1). Are better.
The allyl alcohol copolymer constituting the barrier layer in the laminate of the present invention has a glass transition point (Tg) of −70 ° C. or higher and 40 ° C. or lower and −50 ° C. or higher and 40 ° C. or lower as measured based on JIS K7121. It is preferably −30 ° C. or higher and 40 ° C. or lower, more preferably −10 ° C. or higher and 35 ° C. or lower, and most preferably 0 ° C. or higher and 30 ° C. or lower.
If the glass transition point (Tg) is lower than this range, it is easily deformed, so that the handleability is not sufficient, and if it is higher than this range, the flexibility is inferior.

Condition (C): Weight average molecular weight (Mw)
The weight average molecular weight (Mw) of the allyl alcohol copolymer constituting the barrier layer in the laminate of the present invention is preferably 1000 to 1000,000, more preferably 2000 to 500,000, as measured by the gel permeation chromatography (GPC) method. It is preferable, and 3000 to 100,000 is particularly preferable.
When Mw is 1000 or more, the entanglement between the molecular chains is strengthened, so that the barrier property is likely to be exhibited. When Mw is 1,000,000 or less, the viscosity at the time of solution or melting does not become too high, and molding is easy.

Condition (D): Number of branches with 2 or more carbon atoms in the main chain Branches with 2 or more carbon atoms in the main chain of the allyl alcohol copolymer constituting the barrier layer in the laminate of the present invention form the main chain. The number of carbon atoms is preferably 1 or less per 1000 carbon atoms, and more preferably 0. When the number of branches having 2 or more carbon atoms is 2 or less, thermal deterioration does not occur even when used at a high temperature, and the strength and transparency are less likely to decrease. The side chain of the monomer is not counted as a branch having 2 or more carbon atoms in the present invention. For example, when methyl acrylate is copolymerized as a fourth monomer, a methoxycarbonyl group having 2 carbon atoms becomes a side chain, but this is not a branch having 2 or more carbon atoms. Details are described in the section of manufacturing method described later.

Condition (E): Number of carbon-carbon double bonds present in the main chain The allyl alcohol copolymer constituting the barrier layer in the laminate of the present invention has carbon-carbon double bonds present in the main chain. The number of is preferably 2 or less, and more preferably 1 or less. When the number of carbon-carbon double bonds in the main chain is 2 or less, the polymer chain is cleaved by oxidative cleavage, and the decrease in molecular weight and coloring are prevented. Further, from the viewpoint of reducing the molecular weight and maintaining the performance, it is preferable that the carbon-carbon double bond exists at the end of the main chain structure rather than inside the main chain structure.

[Method for producing allyl alcohol copolymer]
The method for producing the allyl alcohol copolymer of the present invention is not particularly limited. For example, it can be produced by copolymerizing a monomer corresponding to the general formula (1), a monomer corresponding to the general formula (2), and a monomer corresponding to the general formula (3). The monomer corresponding to the general formula (1) is ethylene or propylene, and the monomer corresponding to the general formula (2) is allyl alcohol. From the viewpoint of improving the molecular weight and flexibility of the allyl alcohol copolymer, ethylene is preferable as the monomer corresponding to the general formula (1).

（式中、Ｒ²は一般式（３）と同様の意味を表す。）で示されるアリルエステルである。
一般式（４）で示されるアリルエステルの具体例としては、酢酸アリル、プロピオン酸アリル、酪酸アリル、吉草酸アリル、安息香酸アリル、トリフルオロ酢酸アリル、トリクロロ酢酸アリル、トリブロモ酢酸アリル、安息香酸アリル等が挙げられる。製造コスト、及び加水分解またはけん化反応の反応性の観点から、酢酸アリルが好ましい。 The monomer corresponding to the general formula (3) is the general formula (4).

(In the formula, R ² has the same meaning as that of the general formula (3).) It is an allyl ester represented by the general formula (3).
Specific examples of the allyl ester represented by the general formula (4) include allyl acetate, allyl propionate, allyl butyrate, allyl valerate, allyl benzoate, allyl trifluoroacetate, allyl trichloroacetate, allyl tribromoacetate, allyl benzoate. And so on. Allyl acetate is preferred from the standpoint of production cost and reactivity of hydrolysis or saponification reaction.

Further, in order to produce the monomer structural unit corresponding to the general formula (2), the allyl ester represented by the general formula (4) may be used. That is, by copolymerizing ethylene with the allyl ester represented by the general formula (4) and hydrolyzing or saponifying the obtained copolymer, the monomer structural unit represented by the general formula (2) can be obtained. It is possible to produce a copolymer having it. By controlling the reaction rate of the hydrolysis or saponification reaction, the copolymer may also have a monomer structural unit represented by the general formula (3).

The hydrolysis reaction and saponification reaction of the copolymer can be carried out by a known method.
The hydrolysis reaction is carried out under acidic or basic conditions in a solvent containing water. Examples of the acid used in the hydrolysis reaction include hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid, tolfluoroacetic acid, trichloroacetic acid, tolfluoromethanesulfonic acid, methanesulfonic acid, p-toluenesulfonic acid and the like, and are easily available industrially. From the viewpoint of the above, hydrochloric acid, sulfuric acid, or acetic acid is preferable, and hydrochloric acid is more preferable. Examples of the base used in the hydrolysis reaction include sodium hydroxide, potassium hydroxide, lithium hydroxide and the like. From the viewpoint of industrial availability, sodium hydroxide or potassium hydroxide is preferable, and sodium hydroxide is more preferable. preferable. The solvent containing water used in the hydrolysis reaction may be water alone or a mixture of water and another solvent. Examples of other solvents when using a mixture of water and other solvents include toluene, xylene, cyclohexane, n-hexane, ethyl acetate, methyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, methyl ethyl ketone. , Methylene chloride, chloroform, dichlorobenzene and the like.

The saponification reaction is carried out under basic conditions in a solvent containing alcohol. Examples of the base used in the saponification reaction include sodium hydroxide, potassium hydroxide, lithium hydroxide and the like. Sodium hydroxide or potassium hydroxide is preferable, and sodium hydroxide is more preferable, from the viewpoint of industrial availability. Examples of the alcohol used in the saponification reaction include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol and the like, which are industrially readily available and esters produced as a by-product in the reaction. Methanol, ethanol or isopropanol is preferable, and methanol or ethanol is more preferable, from the viewpoint of easiness of removal. The solvent containing alcohol used in the saponification reaction may be alcohol alone or a mixture of alcohol and another solvent. Examples of other solvents when using a mixture of alcohol and other solvents are toluene, xylene, cyclohexane, n-hexane, ethyl acetate, methyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, methyl ethyl ketone. , Methylene chloride, chloroform, dichlorobenzene and the like.

The above-mentioned monomer polymerization method is not particularly limited, and for example, a known method such as a solution polymerization method, a suspension polymerization method, an emulsion polymerization method, a bulk polymerization method, or a gas phase polymerization method can be used. Further, the polymerization mode can be either a batch mode or a continuous mode, and can be carried out by one-stage polymerization or multi-stage polymerization.

The polymerization type is not particularly limited, but coordinated anionic polymerization is particularly preferable from the viewpoint of reducing the number of branches in the main chain and the number of carbon-carbon double bonds.
When the polymerization form of either ethylene or propylene monomer and allyl alcohol is produced by the coordination anion polymerization method, the polymerization catalyst used is not particularly limited, but the polymerization activity and the characteristics of the obtained polymer are not particularly limited. From this point of view, the metal complex catalyst described in JP-A-2011-68881A, JP-A-2014-159540, International Publication No. 2013/168626, etc. is particularly preferable. The main features of the copolymer obtained by the polymerization using the above-mentioned metal complex catalyst as compared with the polymer obtained by the radical polymerization method used for general polymer production are shown below.
1) A high molecular weight body can be obtained, and the molecular weight distribution (Mw / Mn) is narrow.
2) The backbone structure is substantially linear.
3) It has one carbon-carbon double bond per main chain structural unit at one end or inside of the main chain.

The allyl alcohol or the allyl monomer represented by the general formula (4) has a methylene group at the α-position of the vinyl group, and in the radical polymerization method, due to the degenerative chain transfer due to the extraction of the hydrogen radical of the methylene group of the growing radical. , The polymerization reaction is stopped, and only a copolymer having a low molecular weight can be obtained. When the molecular weight of the copolymer is low, the entanglement between the molecular chains is weakened, so that the barrier property is less likely to be exhibited. Further, it is generally known that the polymer obtained by the radical polymerization method has a wide molecular weight distribution, and Mw / Mn is 4.0 or more.

It is known that the ethylene-based polymer obtained by the radical polymerization method has a branched structure by the backbiting mechanism shown in the following formula. As the branch structure, there are a short chain branch having 5 or less carbon atoms generated by backbiting and a long chain branch grown from a radical generated in the main chain. The main chain structure of the allyl alcohol copolymer constituting the gas barrier resin laminate of the present invention is a linear structure having extremely few of the above-mentioned branched structures, and the number of branched structures having two or more carbon atoms is the main chain. It is 1 or less per 1000 carbon atoms constituting. Here, the number of branches per 1000 carbon atoms can be calculated by measuring the number of tertiary carbons in the main chain to which branches having 2 or more carbon atoms are bonded by ¹³ C-NMR. When there are many branched structures, the amount of tertiary carbon having a relatively high reactivity increases, so that resin deterioration such as oxidative deterioration is likely to occur, especially under light or oxygen contact.

The terminal structure of the polymer backbone can be considered separately as a start end formed at the start of polymerization and a stop end formed at the termination of polymerization. When a metal complex catalyst is used as the coordination anion polymerization catalyst, the starting end becomes a saturated bond because an olefin is inserted into the bond between the metal-hydrogen atom or the bond between the metal-alkyl group, but the stopped end is. , The reaction mechanism is classified into the case of saturated bond and the case of unsaturated bond. It has been reported that when a chain transfer agent having an alkyl group such as organoaluminum is used in a reaction system, the molecular chain is chain-transferred to an aluminum atom to stop the reaction, resulting in a saturated terminal. 3 When a titanium chloride-based Ziegler-Natta catalyst or a metal complex of a Group 4 element of the Periodic Table is used as a catalyst, organic aluminum is used to copolymerize an allyl compound having a polar group, so that the terminal structure is saturated. become.

式中、Ｒは一般式（１）、一般式（２）または一般式（３）におけるＲ¹またはＣＨ₂ＯＨ、または一般式（３）におけるＣＨ₂ＯＣ（＝Ｏ）Ｒ²を表し、Ｐｏｌｙｍｅｒはポリマー鎖を表す。 On the other hand, when the metal complex catalyst described in JP-A-2011-68881A, JP-A-2014-159540, International Publication No. 2013/168626, etc. is used as the polymerization catalyst, organoaluminum is not used. Polymer chain growth is stopped by the β-hydrogen desorption mechanism as shown in the following formula, and a carbon-carbon double bond is formed at one end of the main chain.

In the formula, R represents R ¹ or CH ₂ OH in the general formula (1), the general formula (2) or the general formula (3), or CH ₂ OC (= O) R ² in the general formula (3), and Polymer. Represents a polymer chain.

Further, depending on the polymerization conditions, as shown in the following formula, the hydride-metal species (MH in the formula) is reinserted into the carbon-carbon double bond generated at one end of the generated backbone. Desorption of β-hydrogen may cause carbon-carbon double bonds to move inside the backbone. By proceeding this reaction multiple times, a carbon-carbon double bond is formed at a position gradually away from the end of the main chain.

On the other hand, when the copolymerization is carried out by radical polymerization, a plurality of carbon-carbon double bonds are generated not only at the stop ends of the main chain but also inside the main chain in the obtained copolymer. For the radical generated by the above-mentioned backbiting or the radical generated by the extraction of the hydrogen radical on the tertiary carbon which is the branch point of the branched chain, the carbon-carbon is obtained by the extraction of the hydrogen radical on the α-position carbon. A double bond is generated. If a large number of carbon-carbon double bonds are present, the polymer chain may be cleaved by oxidative cleavage under light or oxygen contact, resulting in a decrease in molecular weight or coloring.
Therefore, from the viewpoint of high temperature stability and weather resistance, it can be said that the copolymer obtained by the polymerization using the above-mentioned metal complex catalyst is superior to the copolymer obtained by the radical polymerization.

[Additive]
If necessary, various additives may be added to the allyl alcohol copolymer of the present invention as long as the barrier property is not impaired.
Examples of the additives include stabilizers (antioxidants, heat stabilizers, ultraviolet absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, colorants, fillers, crystal nucleating agents, inorganic fillers, and the like. Can be mentioned.

The allyl alcohol copolymer of the present invention may contain a plate-like inorganic compound for the purpose of improving the barrier property. Examples of the plate-like inorganic compound include hydrous silicates (ferrosilicate minerals, etc.), kaolinite-serpentine clay minerals (halosite, kaolinite, enderite, dikite, naphthyl, etc., antigolite, chrysotile, etc.), and the like. Pyrophyllite-Tark (pyrophyllite, talc, kerolai, etc.), smectite clay minerals (montmorillonite, byderite, nontronite, saponite, hectrite, soconite, stibunsite, etc.), vermiculite clay minerals (vermiculite, etc.), Mica or mica clay minerals (white mica, gold mica and other mica, margarite, tetrasilic mica, teniolite, etc.), green mudstones (cook silicate, sudowite, clinochloa, chamosite, nimite, etc.), hydrotalcite, plate Examples thereof include barium sulfate, boehmite, and aluminum polyphosphate. These minerals may be natural clays or synthetic clay minerals. In addition, these minerals may be used alone or in combination of two or more.

[Plastic film layer]
The resin constituting the plastic film layer in the laminate of the present invention is not particularly limited and may be appropriately selected depending on the intended use.
Examples of the resin constituting the plastic film layer include polyester films such as polyethylene terephthalate (PET) film, polybutylene terephthalate (PBT) film, and polynaphthalene terephthalate (PEN) film, polystyrene film, polycarbonate (PC) film, and polyamide film. , Polyimide film, Polyallylate film, Polyacrylonitrile film, Polyethylene film (LLDPE: Linear low density polyethylene film, HDPE: High density polyethylene film) Polypropylene film (CPP: Unstretched polypropylene film, OPP: Biaxially stretched polypropylene film) Polypropylene film, polycycloolefin film, polyvinylidene chloride (PVDC) film, polyvinyl chloride (PVC) film, etc.
And these transparent vapor-deposited films and the like.

As the plastic film layer, a polyethylene film layer, a stretched polypropylene film layer, and a polyethylene terephthalate layer are particularly preferable from the viewpoint of improving the gas barrier property as a laminated body and from the viewpoint of easy availability. By using these plastic film layers, it is possible to inexpensively produce a laminate having excellent water vapor barrier property and oxygen barrier property.

The thickness of the plastic film layer is not particularly limited, but is preferably 3 to 500 μm, more preferably 5 to 200 μm, and particularly preferably 10 to 100 μm. If the thickness is 3 μm or more, the film strength is insufficient and there is no risk of tearing when used as a packaging material, and if the thickness is 500 μm or less, transportation and winding are easy.

When the gas barrier resin laminate is produced by the solution casting method described later, various surface treatments such as corona treatment, plasma treatment, and flame treatment may be applied to the surface of the plastic film layer. By performing these surface treatments, in addition to suppressing repelling during casting, the adhesion between the plastic film layer and the barrier resin layer made of an allyl alcohol copolymer is improved. In particular, corona treatment or plasma treatment, which is generally used for packaging materials, is preferable.

When the gas barrier resin laminate is produced by the solution casting method, the plastic film layer may be a transparent thin-film film having a transparent thin-film layer formed on its surface. By laminating a barrier resin layer made of the allyl alcohol copolymer of the present invention on the transparent vapor-deposited layer, the transparent vapor-deposited layer is reinforced to impart flexibility, and further, cracks and pinholes in the transparent vapor-deposited layer are provided. By filling the holes in the barrier resin layer made of the allyl alcohol copolymer of the present invention, it can be expected that the barrier property will be improved as compared with a normal transparent vapor-deposited film. When laminating on a transparent vapor-deposited film, it is desirable that a barrier resin made of an allyl alcohol copolymer is laminated at least on the transparent vapor-deposited surface side. Even when laminated on the opposite side of the transparent thin-film vapor deposition surface, improvement in barrier properties can be expected, but the reinforcing effect of the transparent thin-film deposition layer may not be sufficiently exhibited.
The type of the transparent vapor deposition layer is not particularly limited, but metal oxide vapor deposition generally used for packaging materials is preferable, and aluminum oxide vapor deposition and silicon oxide vapor deposition are particularly preferable. In addition to this, various organic compounds, inorganic compounds, and combinations thereof may be used. The vapor deposition method is not particularly limited, and a known vacuum vapor deposition method, a sputtering method, a chemical vapor deposition (CVD) method, or the like can be used.

[Gas barrier resin laminate]
In the gas barrier resin laminate of the present invention including the gas barrier resin layer, it is preferable to provide the gas barrier resin layer between the plastic film layers. In this case, the two layers of plastic films sandwiching the gas barrier resin layer may be the same or different.

[Manufacturing method of gas barrier resin laminate]
The gas barrier resin laminate of the present invention can be produced by adopting a molding method practiced in a general polymer molding processing field. Specifically, a solution casting method, T-die molding, inflation molding, dry laminating molding, extrusion coating, coextrusion molding, or the like can be adopted. Among these, the solution casting method or coextrusion molding is preferable from the viewpoint of ease of film formation and simplification of the process.

The solution casting method is a method in which a solution prepared by dissolving the allyl alcohol copolymer of the present invention in a solvent is applied or cast on a plastic film layer, and then dried to form a laminate.
As the solvent, water; alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol; ketones such as acetone and methyl ethyl ketone; 2-methoxyethanol (methyl cellosolve), 2-ethoxyethanol ( Ethyl cellosolve), 2-propoxyethanol, 2-butoxyethanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-propoxy-2-propanol, diethylene glycol, glycol monoethers such as monomethyl ether; ethylene glycol Glycol diethers such as dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether; glycol esters such as methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate (PGMEA); N, N-dimethylformamide, N, N-dimethylacetamide , Aprotonic polar solvents such as dimethylsulfoxide and N-methylpyrrolidone, and water-insoluble solvents such as toluene, xylene, methyl acetate, ethyl acetate and n-butyl acetate.

Alcohols and glycol monoethers are preferable, and ethanol and ethyl cellosolve are particularly preferable, from the viewpoints of high solubility of the allyl alcohol copolymer, ease of distillation in the drying step, and safety. These solvents may be used alone or in combination.
Unlike PVA and EVOH, the allyl alcohol copolymer of the present invention has high solubility in alcohols and glycol ethers, is easy to mold, and is highly safe.

The solid content concentration of the solution of the allyl alcohol copolymer is not particularly limited, but is preferably 1 to 50% by mass, more preferably 3 to 30% by mass, and particularly preferably 5 to 20% by mass. When the solid content concentration is 1% by mass or more, the time required for solvent distillation in the drying step can be shortened, and the manufacturing cost can be suppressed. Further, when it is 50% by mass or less, the viscosity of the solution is appropriate, so that uneven thickness and streaks during coating or casting are less likely to occur.

The method for applying or spreading the solution of the allyl alcohol copolymer is not particularly limited, but is limited to bar coater coating, Mayer bar coating, air knife coating, gravure coating, reverse gravure coating, and microgravure coating. Known methods such as work, micro-reverse gravure coater coating, die coater coating, slot die coater coating, vacuum die coater coating, dip coating, spin coating coating, spray coating, and brush coating can be used. ..

The drying method is not particularly limited, but a known method such as blowing hot air with a dryer or the like and irradiating infrared rays can be used.
The drying temperature depends on the heat resistance of the plastic film layer, but is preferably room temperature to 150 ° C., more preferably 50 to 120 ° C., and particularly preferably 60 to 90 ° C. When the drying temperature is room temperature or higher, the time required for drying can be shortened. Further, when the drying temperature is 150 ° C. or lower, there is no possibility that bubbles are generated in the coating layer or the plastic film layer is thermally deformed.

The drying time is not particularly limited, but is preferably between 1 second and 30 minutes, more preferably 3 seconds and 15 minutes, and particularly preferably 5 seconds and 5 minutes. If the drying time is 1 second or more, the solvent is sufficiently distilled off, and if it is 30 minutes or less, the manufacturing cost is appropriate.
When a gas barrier resin laminate is produced by a coextrusion molding method, for example, an allyl alcohol copolymer resin and a thermoplastic resin constituting a plastic film layer are heated and melted, respectively, and then laminated by a multilayer die and extruded. A laminate is obtained by cooling and solidifying.
When performing the coextrusion molding method, an adhesive resin layer (A layer) may be provided for the purpose of improving the adhesiveness between the gas barrier layer (B layer) and the plastic film layer (P layer). As the layer structure in this case, for example, a structure such as B / A / P, P1 / A / B / A / P1, or P1 / A / B / A / P2 is exemplified. Here, P1 and P2 represent different plastic film layers.

The adhesive resin layer is not particularly limited, and for example, a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof can be used.
When the gas barrier resin laminate is produced by the coextrusion method, the thermoplastic resin includes polyolefin resins such as polyethylene and polypropylene, polyamide resins such as polyamide 6, polyamide 66 and nylon MXD6, and polyesters such as polyethylene terephthalate and polybutylene terephthalate. Examples thereof include other resins such as resins, polystyrene resins, polycarbonate resins, ethylene / vinyl acetate copolymers, ethylene / vinyl alcohol copolymers, or mixtures thereof.
Among these thermoplastic resins, a polyamide resin is preferable because it is excellent in puncture resistance and impact resistance when a packaging bag is formed, and a polyester resin is also preferable because it is excellent in heat resistance and economy.

[Construction and physical properties of gas barrier resin laminate]
The thickness of the gas barrier layer in the gas barrier resin laminate of the present invention is not particularly limited, but is preferably between 0.1 and 50 μm, more preferably 0.2 to 30 μm, and particularly preferably 0.5 to 10 μm. When the thickness of the gas barrier layer is 0.1 μm or more, pinholes and cracks do not occur in the gas barrier layer, and the gas barrier property does not deteriorate. Further, when the thickness of the gas barrier layer is 50 μm or less, the flexibility of the gas barrier resin laminate can be maintained.

The total light transmittance of the gas barrier resin laminate of the present invention is preferably 70% or more, more preferably 80% or more, and particularly preferably 85% or more. When the total light transmittance is 70% or more, the visibility of the contents becomes easy.
The total Haze of the gas barrier resin laminate of the present invention is preferably 10% or less, more preferably 5% or less, and particularly preferably 3% or less. When the total Haze is 10% or less, the contents can be easily visually recognized.

The oxygen permeability of the gas barrier resin laminate of the present invention is preferably 100 cm ³ / (m ² / day / atm) or less under low humidity conditions (0% RH), and is 50 cm ³ / (m ² / day /). Atm) or less is more preferable, and 10 cm ³ / (m ² / day / atm) or less is particularly preferable. When the oxygen permeability under low humidity conditions (0% RH) is 100 cm ³ / (m ² / day / atm) or less, the effect of delaying oxygen deterioration of the contents can be expected.

The oxygen permeability of the gas barrier resin laminate of the present invention is preferably 150 cm ³ / (m ² / day / atm) or less under high humidity conditions (90% RH), and is 120 cm ³ / (m ² /). Day / atm) is more preferred, and 100 cm ³ / (m ² / day / atm) is particularly preferred. When the oxygen permeability under high humidity conditions (90% RH) is 150 cm ³ / (m ² / day / atm) or less, the effect of delaying oxygen deterioration of the contents can be expected.

The gas barrier resin laminate of the present invention may be stretched at least uniaxially. The method of stretching is not particularly limited, and a known method can be used. Specifically, by using a tenter type simultaneous biaxial stretching machine to perform simultaneous biaxial stretching in the longitudinal direction (MD) and the lateral direction (TD) on the unstretched gas barrier resin laminate, simultaneous biaxial stretching is performed. The resulting gas-barrier resin laminate can be obtained.

The gas barrier resin laminate of the present invention may be irradiated with high-energy rays such as ultraviolet rays, X-rays, and electron beams, if necessary. In such a case, a component that is crosslinked or polymerized by high energy irradiation may be blended as long as the gas barrier property and flexibility are not impaired.
If necessary, the gas barrier resin laminate of the present invention may be subjected to surface treatment such as corona treatment.

The gas barrier resin laminate of the present invention can be made into various laminated films by laminating a sealant resin.
Resins used as sealants include low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, ethylene / propylene copolymer, ethylene / vinyl acetate copolymer, ionomer resin, and ethylene / acrylic acid. Examples thereof include copolymers, polyethylene / methacrylic acid copolymers, ethylene / acrylic acid ester copolymers, polyethylene / methacrylic acid ester copolymers, polyvinyl acetate-based resins, etc., and the heat seal strength and the strength of the material itself are high. Polyethylene resins such as various polyethylenes, polypropylenes, and ethylene / propylene copolymers are preferable. These resins may be used alone, copolymerized with other resins, melt-mixed, or further subjected to acid modification or the like.

As a method of forming the sealant layer on the gas barrier resin laminate, a method of laminating a film or sheet made of a sealant resin on the gas barrier resin laminate via an adhesive, or a method of laminating the sealant resin on the gas barrier resin laminate. Examples include a method of extrusion laminating. In the former method, the film or sheet made of the sealant resin may be in an unstretched state or in a stretched state with a low magnification, but it is practically preferable to be in an unstretched state.
The thickness of the sealant layer is not particularly limited, but is preferably 20 to 100 μm, more preferably 40 to 70 μm.

A packaging bag can be produced using the gas barrier resin laminate of the present invention. This packaging bag is used for various food and drink products such as food and drink, fruits, juice, drinking water, liquor, cooked food, fish paste products, frozen food, meat products, simmered food, rice cake, liquid soup, seasonings, etc. , Suitable for filling and packaging of contents such as liquid detergents, cosmetics and chemical products.

Hereinafter, the present invention will be described in more detail with reference to synthetic examples, examples and comparative examples, but the present invention is not limited to these examples. In addition, "part" and "%" in an Example are based on mass unless otherwise specified.
The tests and evaluations in the examples and comparative examples were carried out by the following methods.

(1) Weight average molecular weight (Mw) and number average molecular weight (Mn) of the polymer
Size exclusion chromatography (solvent:) using Pullulan as a standard substance of molecular weight using a GPC device Alliance e2695 manufactured by Waters Co., Ltd. equipped with an Asahipak (registered trademark) GF-310HQ column (two in series) manufactured by Showa Denko KK. It was calculated by methanol / water = 1: 1, temperature: 40 ° C.).

(2) Copolymerization ratio of polymer The content of the monomer structural units represented by the general formulas (1) and (2) is determined by using a nuclear magnetic resonance apparatus JNM-ECS400 manufactured by JEOL Ltd. as a solvent. It was determined by ¹ H and ¹³ C-NMR analysis at 120 ° C. using 1,1,2,2-tetrachloroethane-d4.

(3) Branched structure The branched structure can be determined by the chemical shift of the peak derived from the tertiary carbon atom in the ¹³ C-NMR spectrum. That is, the peak of the tertiary carbon atom existing in the allyl alcohol monomer structural unit is observed at 37.9 ppm, whereas when the polymer backbone has a branch, the chemical shift value of the peak of the tertiary carbon atom is observed. Is observed in the vicinity of 38.2 to 39.0 ppm, and the two can be distinguished (Reference: Macromolecules 1999, 32, 1620-1625.).

(4) Carbon-carbon double bond The presence or absence and position of a carbon-carbon double bond can be analyzed by ¹³ C-NMR spectrum. When a carbon-carbon double bond is present at the end of the main chain structure, it can be distinguished from the saturated terminal structure in which peaks are observed around 114 ppm and 139 ppm and peaks appear at 10 to 40 ppm. On the other hand, when a carbon-carbon double bond is formed inside the main chain structure, a peak is observed around 125 to 135 ppm, which can be distinguished from the terminal carbon-carbon double bond (Reference: Chem.Commun). .2002, 744-745.).

(5) Total light transmittance and total Haze
The measurement was performed using a haze meter NDH2000 (manufactured by Nippon Denshoku Co., Ltd.).

(6) Adhesion The adhesion test was performed with a width of 2 mm (25 squares) according to JIS K5600-5-6, and the adhesion was evaluated according to the 6-step classification described in JIS K5600-5-6. In this classification, if there is no peeling in all the squares, it is regarded as "classification 0".

(7) Gas barrier property Oxygen permeability was measured at 20 ° C. and relative humidity of 0% RH and 90% RH according to JIS K7126-2 (Appendix A).

(8) Glass transition point (Tg)
Measurement was performed based on JIS K7121 using a differential scanning calorimeter (DSC) device name X-DSC7000 manufactured by Seiko Electronics Inc. That is, by the method described in JIS, the sample is once heated to 200 ° C., then cooled to a temperature about 50 ° C. lower than the expected glass transition point at a cooling rate of 30 ° C./min, and the temperature rise rate is 10 again. The intermediate point glass transition temperature (Tmg) measured by raising the temperature at ° C./min was defined as the glass transition point (Tg).

続いて、得られたエチレン・酢酸アリル共重合体のけん化反応を行った。窒素ガス雰囲気下、エチレン・酢酸アリル共重合体（５．３ｇ）、トルエン（１２０ｍＬ）及びメタノール（６５ｍＬ）を含む１Ｌセパラブルナスフラスコに、水酸化ナトリウム（和光純薬工業（株）製、０．０７５ｇ、１．９ｍｍｏｌ）のメタノール溶液（１０ｍＬ）を加え、加熱還流下、３時間撹拌させた。室温まで冷却後、反応液を水・アセトン混合溶媒（１：１ｖｏｌ／ｖｏｌ、１Ｌ）に加え、重合体を析出させた。生じた重合体をろ過によって回収し、メタノールで洗浄した後に減圧下乾燥して、エチレン・アリルアルコール共重合体である共重合体（ＥＡ４０）を得た。収量は３．０ｇであった。分子量は、サイズ排除クロマトグラフィーにより、数平均分子量４，８００、重量平均分子量７，６００と算出し、Ｍｗ／Ｍｎは１．５７であった。共重合体中のアリルアルコール含有率は、¹Ｈ－ＮＭＲ及び¹³Ｃ－ＮＭＲ測定により、エチレン：アリルアルコールのモル比は６０．０：４０．０（アリルアルコールモル分率＝４０．０％）と算出された。さらに、¹³Ｃ－ＮＭＲ測定により、主鎖中に存在する炭素原子数２以上の分岐は観測されず、ケミカルシフト値１１４ｐｐｍ及び１３９ｐｐｍのピークから、主鎖構造単位あたり１個の炭素－炭素二重結合が、主鎖の片末端に存在することが判った。Ｔｇは１５．０℃であった。 Synthesis Example 1: 40 mol% ethylene / allyl alcohol copolymer (EA40)
Allyl acetate (1.0 L) filled with ethylene gas (0.12 MPa) at 40 ° C. in a 2 L autoclave under a nitrogen gas atmosphere is charged with the following metal complex catalyst 1 (0.69 g, 1.0 mmol, published publication). : A solution of allyl acetate (90 mL) (described in JP-A-2014-159540) was added, and the mixture was stirred at 40 ° C. for 90 hours. The ethylene gas was purged with nitrogen gas, cooled to room temperature, and then the reaction solution in the autoclave was concentrated under reduced pressure to obtain an ethylene / allyl acetate copolymer. The yield was 9.0 g.

Subsequently, the saponification reaction of the obtained ethylene / allyl acetate copolymer was carried out. Sodium hydroxide (manufactured by Wako Pure Chemical Industries, Ltd., 0) in a 1 L separable eggplant flask containing an ethylene / allyl acetate copolymer (5.3 g), toluene (120 mL) and methanol (65 mL) under a nitrogen gas atmosphere. A methanol solution (10 mL) of .075 g (1.9 mmol) was added, and the mixture was stirred under heating and reflux for 3 hours. After cooling to room temperature, the reaction solution was added to a mixed solvent of water and acetone (1: 1 vol / vol, 1 L) to precipitate a polymer. The resulting polymer was recovered by filtration, washed with methanol, and then dried under reduced pressure to obtain a copolymer (EA40) which is an ethylene / allyl alcohol copolymer. The yield was 3.0 g. The molecular weight was calculated by size exclusion chromatography to have a number average molecular weight of 4,800 and a weight average molecular weight of 7,600, and Mw / Mn was 1.57. The allyl alcohol content in the copolymer was measured by ¹ H-NMR and ¹³ C-NMR, and the molar ratio of ethylene: allyl alcohol was 60.0: 40.0 (allyl alcohol mole fraction = 40.0%). Was calculated. Furthermore, by ¹³ C-NMR measurement, no branching with 2 or more carbon atoms existing in the main chain was observed, and one carbon-carbon double per main chain structural unit was observed from the peaks of the chemical shift values of 114 ppm and 139 ppm. The bond was found to be at one end of the backbone. Tg was 15.0 ° C.

Synthesis Example 2: 18 mol% ethylene / allyl alcohol copolymer (EA18)
The metal complex catalyst 1 (1.0 g, 1.4 mmol) used in Synthesis Example 1 was mixed with allyl acetate (1 L) filled with ethylene gas (0.5 MPa) at 65 ° C. in a 2 L autoclave under a nitrogen gas atmosphere. Toluene solution (40 mL) was added, and the mixture was stirred at 65 ° C. for 30 hours. Ethylene gas was purged with nitrogen gas, cooled to room temperature, and then the reaction solution in the autoclave was concentrated under reduced pressure to about 100 mL. The concentrate was added to methanol (1 L) to precipitate a polymer. The resulting polymer was recovered by filtration, washed with methanol, and then dried under reduced pressure to obtain an ethylene / allyl acetate copolymer. The yield was 13.3 g.
Subsequently, the saponification reaction of the obtained ethylene / allyl acetate copolymer was carried out. Sodium hydroxide (manufactured by Wako Pure Chemical Industries, Ltd., 0) in a 1 L separable eggplant flask containing an ethylene / allyl acetate copolymer (10.3 g), toluene (140 mL) and methanol (75 mL) under a nitrogen gas atmosphere. A solution of methanol (0.088 g, 2.2 mmol) (10 mL) was added, and the mixture was stirred under heating under reflux for 2.5 hours. After cooling to room temperature, the reaction solution was added to methanol (1 L) to precipitate a polymer. The resulting polymer was recovered by filtration, washed with methanol, and then dried under reduced pressure to obtain a copolymer (EA18) which is an ethylene / allyl alcohol copolymer. The yield was 8.1 g. The molecular weight was calculated by size exclusion chromatography to have a number average molecular weight of 46,000 and a weight average molecular weight of 70,000, and Mw / Mn was 1.53. The allyl alcohol content in the copolymer was measured by ¹ H-NMR and ¹³ C-NMR, and the molar ratio of ethylene: allyl alcohol was 82.0: 18.0 (allyl alcohol mole fraction = 18.0%). I decided. Furthermore, by ¹³ C-NMR measurement, no branching with 2 or more carbon atoms existing in the main chain was observed, and one carbon-carbon double per main chain structural unit was observed from the peaks of the chemical shift values of 114 ppm and 139 ppm. The bond was found to be at one end of the backbone. Tg was 4.3 ° C.

続いて、得られたエチレン・酢酸アリル共重合体のけん化反応を行った。窒素ガス雰囲気下、エチレン・酢酸アリル共重合体（３．５ｇ）及びメタノール（１２０ｍＬ）を含む５００ｍＬセパラブルナスフラスコに、水酸化ナトリウム（和光純薬工業（株）製、０．１３ｇ、３．２ｍｍｏｌ）のメタノール溶液（５ｍＬ）を加え、加熱還流下、５時間撹拌させた。室温まで冷却後、反応液を水に加え、重合体を析出させた。生じた重合体をろ過によって回収し、アセトンで洗浄した後に減圧下乾燥して、エチレン・アリルアルコール共重合体である共重合体（ＥＡ６０）を得た。収量は０．７４ｇであった。分子量は、サイズ排除クロマトグラフィーにより、数平均分子量１，３００、重量平均分子量３，０００と算出し、Ｍｗ／Ｍｎは２．３１であった。共重合体中のアリルアルコール含有率は、¹Ｈ－ＮＭＲ及び¹³Ｃ－ＮＭＲ測定により、エチレン：アリルアルコールのモル比は４２．６：５７．４（アリルアルコールモル分率＝５７．４％）と算出された。さらに、¹³Ｃ－ＮＭＲ測定により、主鎖中に存在する炭素原子数２以上の分岐は観測されず、ケミカルシフト値１１４ｐｐｍ及び１３９ｐｐｍのピークから、主鎖構造単位あたり１個の炭素－炭素二重結合が、主鎖の片末端に存在することが判った。Ｔｇは２１．０℃であった。 Synthesis Example 3: Synthesis of 60 mol% ethylene / allyl alcohol copolymer (EA60) Allyl acetate (240 mL) filled with ethylene gas (0.54 MPa) at 120 ° C. in a 500 mL autoclave under a nitrogen gas atmosphere is described below. A solution of allyl acetate (30 mL) of the metal complex catalyst 2 (0.69 g, 0.12 mmol) was added, and the mixture was stirred at 120 ° C. for 72 hours. The ethylene gas was purged with nitrogen gas, cooled to room temperature, and then the reaction solution in the autoclave was concentrated under reduced pressure to obtain an ethylene / allyl acetate copolymer. The yield was 3.5 g.

Subsequently, the saponification reaction of the obtained ethylene / allyl acetate copolymer was carried out. Sodium hydroxide (manufactured by Wako Pure Chemical Industries, Ltd., 0.13 g, 3. 2 mmol) of methanol solution (5 mL) was added, and the mixture was stirred under heating and reflux for 5 hours. After cooling to room temperature, the reaction solution was added to water to precipitate the polymer. The resulting polymer was recovered by filtration, washed with acetone, and then dried under reduced pressure to obtain a copolymer (EA60) which is an ethylene / allyl alcohol copolymer. The yield was 0.74 g. The molecular weight was calculated by size exclusion chromatography to have a number average molecular weight of 1,300 and a weight average molecular weight of 3,000, and Mw / Mn was 2.31. The allyl alcohol content in the copolymer was measured by ¹ H-NMR and ¹³ C-NMR, and the molar ratio of ethylene: allyl alcohol was 42.6: 57.4 (allyl alcohol mole fraction = 57.4%). Was calculated. Furthermore, by ¹³ C-NMR measurement, no branching with 2 or more carbon atoms existing in the main chain was observed, and one carbon-carbon double per main chain structural unit was observed from the peaks of the chemical shift values of 114 ppm and 139 ppm. The bond was found to be at one end of the backbone. Tg was 21.0 ° C.

Example 1:
The EA40 synthesized in Synthesis Example 1 was dissolved in ethanol at room temperature so as to have a solid content concentration of 10% by mass, and stirred to prepare a uniform solution. The obtained solution was applied to a PET film having a thickness of 12 μm (Lumirror (registered trademark) P60 manufactured by Toray Film Processing Co., Ltd.) so as to have a dry film thickness of 5 μm using a baker applicator, and the temperature was set to 80 ° C. It was dried in a hot air circulation tank for 10 minutes to obtain a laminate. The number of squares remaining in the cross-cut test of the obtained laminate was 25 out of 25 squares (classification 0), the total light transmittance was 89.3%, and the total Haze was 2.4%. Oxygen permeability at 0% RH is 70 cm ³ / (m ² / day / atm), oxygen permeability at 90% RH is 89 cm ³ / (m ² / day / atm), and oxygen at 0% RH. The oxygen permeability ratio at 90% RH to permeability was 1.3.

Example 2:
A laminate was obtained in the same manner as in Example 1 except that the solvent was changed to ethyl cellosolve. The number of squares remaining in the cross-cut test of the obtained laminate was 25 out of 25 squares (classification 0), the total light transmittance was 89.3%, and the total Haze was 2.2%. Oxygen permeability at 0% RH is 76 cm ³ / (m ² / day / atm), oxygen permeability at 90% RH is 98 cm ³ / (m ² / day / atm), and oxygen at 0% RH. The oxygen permeability ratio at 90% RH to permeability was 1.3.

Example 3:
The EA60 synthesized in Synthesis Example 3 was dissolved in ethanol at room temperature so as to have a solid content concentration of 10% by mass, and stirred to prepare a uniform solution. The obtained solution was applied to an OPP film (FOR® manufactured by Futamura Chemical Co., Ltd.) having a thickness of 30 μm so as to have a dry film thickness of 5 μm using a baker applicator, and hot air circulation was set at a temperature of 80 ° C. It was dried in a tank for 10 minutes to obtain a laminate. The number of squares remaining in the cross-cut test of the obtained laminate was 25 out of 25 squares (classification 0), the total light transmittance was 91.5%, and the total Haze was 1.3%. Oxygen permeability at 0% RH is 23 cm ³ / (m ² / day / atm), oxygen permeability at 90% RH is 105 cm ³ / (m ² / day / atm), and oxygen at 0% RH. The oxygen permeability ratio at 90% RH to permeability was 4.5.

Comparative Example 1:
For PVA (Tg = 71.0 ° C.) coated OPP film (manufactured by Mitsui Chemicals Tohcello Corporation) with a thickness of 21 μm (barrier layer thickness of 1 μm), the total light transmittance is 91.5% and the total Haze is 1.4%. there were. The oxygen permeability at 0% RH is 0.1 cm ³ / (m ² / day / atm), the oxygen permeability at 90% RH is 600 cm ³ / (m ² / day / atm), and at 0% RH. The oxygen permeability ratio at 90% RH to the oxygen permeability of was 6000.

Comparative Example 2:
Soanol (registered trademark) A4412 (vinyl alcohol mole fraction = 56 mol%, Tg = 55) manufactured by Nippon Synthetic Chemical Industry Co., Ltd., which is an ethylene / vinyl alcohol copolymer (EVOH resin) instead of the allyl alcohol copolymer. Attempt to obtain a laminate using (0.0 ° C.). Ethanol was added to Soanol A4412 so that the solid content concentration was 5% by mass, and the mixture was heated at 90 ° C. for 1 hour with stirring, but did not dissolve, and a uniform solution necessary for producing a laminate by the solution casting method was obtained. I couldn't.

Comparative Example 3:
Instead of EA40, EA18 produced in Synthesis Example 2 was used to try to obtain a laminate. Ethanol was added to EA18 so that the solid content concentration was 5% by mass, and the mixture was heated at 40 ° C. for 60 hours with stirring, but did not dissolve, and a uniform solution necessary for producing a laminate by the solution casting method could be obtained. could not.

Comparative Example 4:
An attempt was made to dissolve EA18 in the same manner as in Comparative Example 3 except that the solvent was changed to ethyl cellosolve, but the solution was not dissolved, and a uniform solution necessary for producing a laminate by the solution casting method could not be obtained.

Table 1 shows the evaluation results of the laminates produced in the above production examples and examples.

From the results shown in Table 1, the gas barrier laminate of the present invention exhibits good adhesion without applying an anchor coat layer or the like to the plastic film layer, is transparent, and exhibits good oxygen barrier properties. You can see that there is. Further, it can be seen that the change in oxygen permeability between the condition under high humidity (90% RH) and the condition under low humidity (0% RH) is remarkably small, unlike the laminate using PVA resin.

The gas barrier resin laminate of the present invention has a small change in barrier property due to humidity, and can be used as a packaging material for foods, pharmaceuticals, and the like.

Claims (15)

Plastic film layer, and general formula (1), general formula (2) and general formula (3)

(In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, or an amino group. , M and n are numerical values representing the molar ratio of each monomer structural unit, and n may be 0.)
It is an allyl alcohol copolymer containing the monomer structural unit represented by (A), and the molar ratio l, m and the monomer structural unit represented by the general formula (1), the general formula (2) and the general formula (3). n is a gas barrier resin laminate having a gas barrier resin layer containing an allyl alcohol copolymer satisfying the relationship of the following formula: 30 ≦ {(m + n) / (l + m + n)} × 100 ≦ 80, and the allyl. A gas barrier resin laminate having an alcohol copolymer (B) having a glass transition point of −70 ° C. or higher and 40 ° C. or lower . The gas barrier resin laminate according to claim 1, wherein the (C) weight average molecular weight (Mw) of the allyl alcohol copolymer is 1000 or more and 1,000,000 or less. The gas barrier resin laminate according to claim 1 or 2 , wherein the number of branches having 2 or more carbon atoms is 1 or less per 1000 carbon atoms constituting the (D) main chain of the allyl alcohol copolymer. The gas barrier resin laminate according to any one of claims 1 to 3 , wherein the number of carbon-carbon double bonds present in the (E) main chain of the allyl alcohol copolymer is 2 or less. The gas barrier resin laminate according to any one of claims 1 to 4 , wherein the allyl alcohol copolymer has only the monomer structural units represented by the general formula (1) and the general formula (2). The gas barrier resin laminate according to any one of claims 1 to 5 , wherein R ¹ in the general formula (1) is a hydrogen atom. The gas barrier resin according to any one of claims 1 to 6 , wherein the hydrocarbon group having 1 to 20 carbon atoms represented by R ² is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms. Laminate. The gas barrier according to any one of claims 1 to 7 , wherein the plastic film is at least one selected from a polyethylene film, a stretched or unstretched polypropylene film, a polyethylene terephthalate film, a polyamide film, a cellophane film, and a polycycloolefin. Sex resin laminate. The gas barrier resin laminate according to any one of claims 1 to 8 , wherein the plastic film is a transparent vapor-deposited film. The gas barrier resin laminate according to any one of claims 1 to 9 , which has a gas barrier layer between the plastic film layers. The gas barrier resin laminate according to any one of claims 1 to 10 , wherein a solution prepared by dissolving an allyl alcohol copolymer in a solvent is applied to the surface of a plastic film and dried to form a gas barrier layer. Production method. The method for producing a gas barrier resin laminate according to claim 11 , wherein the solvent contains alcohols or glycol monoethers. The method for producing a gas barrier resin laminate according to claim 11 or 12 , wherein a plastic film subjected to any surface treatment of corona treatment, plasma treatment, flame treatment, or easy-adhesive layer coating treatment is used. The method for producing a gas barrier resin laminate according to any one of claims 1 to 10 , wherein the plastic film and the gas barrier film are molded by a coextrusion molding method. A packaging material using the gas barrier resin laminate according to any one of claims 1 to 10 .