JP3154787B2 - Resin composition, multilayer structure and multilayer package - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modified acrylic resin (B) containing a saponified ethylene-vinyl ester copolymer (A) and a glutarimide unit, which is excellent in heat resistance, hot water resistance and gas barrier properties. )) And a multilayer structure.

[0002]

2. Description of the Related Art Saponified ethylene-vinyl ester copolymer (hereinafter referred to as EVOH) is a resin having a high gas barrier property, and multilayer containers and multilayer films using the same are used for food packaging. However, due to the lack of heat resistance and hot water resistance of EVOH, there have been applications where the method of use is limited or where it cannot be used. An example is shown below.

[0003] An example in which insufficient heat resistance is pointed out is EV.
EVO such as OH layer / polyethylene (PE) layer
There is a problem of fusing EVOH to a heat sealer of a multilayer film using H as the outermost layer. Normally, the packaging bag of the multi-layered film is formed by adding the EVOH to the heating section of the heat sealer after the PE sides of the two films having the above-mentioned structures are combined.
It is manufactured by contacting the sides (outside of the bag), heating, pressing and fusing the PE by heat transfer. However, at this time, depending on the type and thickness of the PE, a large amount of heat is required for the fusion, and the EVOH is melted before reaching the temperature at which the PE is fused. There was a case. Therefore, it is necessary to adopt a configuration capable of heat sealing at a low temperature or to provide a protective layer such as nylon outside the EVOH.

[0004] As an example where the lack of hot water is pointed out,
There is retort sterilization use. In this case, a biaxially stretched nylon film / EVOH / polypropylene multilayer bag from the outer layer is considered to be good in terms of strength and the like. However, when this composition was used as a packaging material and retort sterilized, EVOH was plasticized with water, causing delamination, layer disorder and whitening, and was unusable.

Japanese Patent Application Laid-Open No. 1-253442 discloses that hot water resistance is improved by blending EVOH with polyamide, polyolefin, polyester or polycarbonate. This blend layer is used as an intermediate layer, a biaxially stretched nylon film as an outer layer, and a biaxially stretched nylon film as an inner layer. It is shown that a multilayer structure provided with a polypropylene layer can be retorted. However, in this multilayer structure, the hot water resistance is not sufficient, and the heat resistance at the time of heat sealing is not sufficient. In addition, this composition is liable to cause gelation due to a crosslinking reaction at the time of ripening, and has a problem in a long-term film-forming operation. On the other hand, the oxygen gas barrier property of this composition after retorting is slightly lower than that before retorting, and improvement in both production and performance has been required.

JP-A-2-225551 discloses that glutarimidized acrylic resin contains a small amount of EVOH (about 2.5 to about 40).
(% By weight) Blend is described, but sufficient gas barrier properties cannot be imparted.

[0007]

As described above, as described above, E
None of the VOH-based resin compositions has heat resistance, hot water resistance, gas barrier properties, and sufficient moldability and strength. Thus, the first object of the present invention is excellent in heat resistance and hot water resistance,
Moreover, it is to provide a composition having excellent gas barrier properties and moldability.

Further, a second object of the present invention is to provide a gas barrier by retort which has excellent heat resistance and hot water (retort resistance), and is capable of performing molding for a long time. Manufacturing aspect,
An object of the present invention is to provide a resin composition having improved performance in both aspects.

[0009]

The first object is to provide an electric vehicle.
A modified acrylic resin containing 97 to 50% by weight of OH (A) and at least 2 mol% of glutarimide units (hereinafter referred to as GI-
This is achieved by providing a resin composition comprising (B) 3 to 50% by weight.

The second object is to provide an EVOH (A) 94
3 to 47% by weight of a modified acrylic resin (B) containing at least 2% by mole of glutarimide units ,
This is achieved by providing a resin composition comprising 3 to 47% by weight of the polyamide (C) .

Hereinafter, the present invention will be described in more detail. In the present invention, the EVOH (A) includes any one as long as it is obtained by hydrolyzing an ester of ethylene and a vinyl ester. 20 to 65 mol%, preferably 20 to 45 mol%, and a saponification degree of 90% or more, more preferably 96% or more, especially 98 mol or more, and a melt flow index (MFI) (2
50 ° C., 2160 g) as 2 to 600 g / 10
A range of minutes is exemplified. If the ethylene content is less than 20 mol%, the gas barrier property at high humidity decreases, and if it exceeds 65 mol%, a sufficient gas barrier property cannot be obtained. On the other hand, when the degree of saponification is as high as 90 mol%, not only does the gas barrier property at high humidity deteriorate, but also the thermal stability of EVOH deteriorates, and a gel is easily generated on the obtained film surface. As a vinyl ester, vinyl acetate is mentioned as a typical example, but other vinyl esters, for example, fatty acid vinyl esters (vinyl propionate, vinyl pivalate, etc.) can also be used.

Further, EVOH (A) further contains a small amount of unsaturated olefins such as α-olefins such as propylene, isobutene, 4-methylpentene-1, hexene and octene, itaconic acid, methacrylic acid, acrylic acid and maleic anhydride. Carboxylic acids, salts thereof, partial or complete esters thereof, nitriles thereof, amides thereof, anhydrides thereof, vinylsilane compounds such as vinyltrimethoxysilane, unsaturated sulfonic acids,
A copolymer component such as a salt thereof or an alkyl thiol may be contained.

The EVOH (A) may be a mixture of two or more EVOHs having different ethylene contents.
In addition, two or more types of EVOH having different degrees of polymerization and saponification are used.
May be used. Furthermore, both the ethylene content and the degree of polymerization or the degree of saponification may be different.

In the present invention, GI-PMMA may be an N-hydrogen glutarimide unit represented by the general formula (1) (where R ₁ and R ₂ are each hydrogen or a methyl group), or (2) A) a glutarimide unit represented by the formula (wherein R ₃ is an alkyl, aryl (aryl), alkaryl, or aralkyl group, and each group has 1 to 9, preferably 1 to 6 carbon atoms). (Preferably) is an acrylic polymer containing at least 2 mol%, preferably 5 mol% to 80 mol% as a copolymer component. 2
% Or less, the compatibility with EVOH is poor, and the object of the present invention cannot be obtained.

[0015]

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[0016]

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The method for producing GI-PMMA is not particularly limited. For example, an acrylic polymer or a methacrylic polymer and ammonia or a primary amine can be obtained in an extruder in a substantially anhydrous state obtained by the following method. And about 200
A method of producing an imidized acrylic resin soluble in dimethylformamide (DMF) by reacting at a temperature of from 450C to 450C.

Alternatively, the general formula CH ₂ ＣＲCR ₄ Y (where R
₄ represents hydrogen or a methyl group; Y represents CONHR ₅ where R ₅ represents hydrogen, an alkyl group, an aryl group, or an aralkyl group. ) And methyl methacrylate are copolymerized in a methanol solvent containing 30% by weight or less of water in the presence of a radical polymerization catalyst. A part of double mole of methyl methacrylate was previously added to the solvent together with the acrylic amide in the solvent, mixed and dissolved, copolymerized while supplying the remaining methyl methacrylate, and then subjected to an imidization reaction in the presence of a basic catalyst. And converting the acrylic amide unit into a glutarimide unit in the copolymer substantially completely to produce the copolymer.

The degree of polymerization of GI-PMMA is not particularly limited, but when melt-blending with EVOH as will be described later, it is preferable that the viscosity is close to obtain a high degree of dispersion easily. MFI is 0.1 to 100 g / 10 min (2160
g), preferably 0.5 to 50.

GI-PMMA is obtained by polymerizing another monomer unit, for example, methyl methacrylate using an acrylate ester and an aromatic vinyl compound in an amount of 0.1 mol or less. May be obtained.

The composition ratio of EVOH (A) and GI-PMMA (B) constituting the composition for achieving the first object of the present invention is 97 to 50% by weight: 3 to 50% by weight,
Preferably, it is 95 to 60% by weight: 5 to 40% by weight. In the present invention, this composition ratio is important, and GI-PMMA
When the amount of the component is small, adhesion to the heat seal bar due to poor heat resistance, whitening after retort due to poor hot water resistance, poor appearance such as wrinkles, and impact resistance are also reduced.
Conversely, if the amount of GI-PMMA is too large, the barrier properties are reduced, and further, gels and bumps are generated.

The composition for achieving the second object of the present invention comprises 94 to 50% by weight of EVOH (A) and GI-P
MMA (B) 3 to 47% by weight , and polyamide (C)
It is a resin composition comprising 3 to 47% by weight. Such a resin composition has excellent heat resistance and hot water resistance as is clear from Examples 2-1 to 2-10 to be described later , and further has excellent moldability capable of performing molding operation for a long time. And the deterioration of gas barrier properties due to the retort is small. A preferred composition ratio is 94 to 50% by weight of A, 3 to 40% by weight of B, 3 to 40% by weight of C, and more preferably 90 to 50% by weight of A.
60% by weight, B is 5 to 30% by weight, C is 5 to 30% by weight
It is. Here, the term "% by weight" refers to% by weight based on the total amount of (A), (B) and (C). If the components B and C are small, poor appearance such as adhesion to a heat seal bar, whitening after retorting, and wrinkles due to poor heat resistance occurs. Conversely, if B and C are too large, the barrier properties are undesirably reduced. The ratio of C: B is not particularly limited as long as it is in the above range, but is preferably 1: 0.2 to 0.2: 1.

The polyamide resin (PA) of the resin (C) includes polycapramid (nylon-6), poly-ω-aminoheptanoic acid (nylon-7), poly-ω
-Aminononanoic acid (nylon-9), polyundecaneamide (nylon-11), polylauryl lactam (nylon-12), polyethylenediamine adipamide (nylon-2,6), polytetramethylene adipamide (nylon-4) , 6), polyhexamethylene adipamide (nylon 6,6), polyhexamethylene dodecaneamide (nylon-6,12), polyoctamethylene adipamide (nylon-8,6), polydecamethylene adipamide (Nylon-10,6), polydodecamethylenezebamide (nylon-10,8), or caprolactam /
Lauryl lactam copolymer (nylon 6/12), caprolactam / hexamethylene diammonium adipate copolymer (nylon-6 / 6,6), caprolactam /
ω-amino nonanoic acid copolymer (nylon-6 / 9), caprolactam / hexamethylene diammonium adipate copolymer (nylon-12 / 6,6), hexamethylene diammonium adipate / hexamethylene diammonium sebacate copolymer (Nylon-6,6 / 6,
10), ethylene diammonium adipate / hexamethylene diammonium adipate copolymer (nylon-
2,6 / 6,6), caprolactam / hexamethylenediammonium adipate / hexamethylenediammonium sebacate copolymer (nylon-6 / 6,6 / 6,1)
0), polyhexamethylene isophthalamide, polyhexamethylene terephthalamide, hexamethylene isophthalamide / terephthalamide copolymer and the like.

Among these PAs, the most preferred ones for the present invention include caprolactam / lauryl lactam copolymer (nylon-6 / 12) and caprolactam / hexamethylene diammonium adipate copolymer (nylon- 6/6, 6). Both are nylon-
There are no particular restrictions on the 6 components, but if it is 12 components, it is 3-6.
If it is 0% by weight and 6,6 components, 1 to 50% by weight is preferable because of good compatibility with EVOH. Further, its relative viscosity is 2.0 to 3.6, more preferably 2.2 to 3.6.
It is in the range of 3.2.

These PAs, especially nylon-6 /
12. PA having a polyter bond in a polymer chain by adding diamine or dicarboxylic acid of nylon-6 / 6,6
It may be. Further, those in which an aliphatic amine such as hexamethylenediamine, laurylamine or laurylamine, or an aromatic amine such as metaxylenediamine or methylbenzylamine are added to reduce the amount of carboxyl groups in PA are also preferable. . In that case, the amino terminal group is 8
^{X10 -5} equivalents / g or more and 3 × 1 carboxyl end groups
0 may be set to be ^-5 eq / g or less.

Examples of the polyolefin of the resin (C) include ionomer resin, high-density, medium-density, low-density and linear low-density polyethylene, butene, hexene, and the like.
Copolymers of α-olefins such as 4-methyl-1-pentene and ethylene, polypropylene homopolymer, polypropylene polymer obtained by grafting or block copolymerizing ethylene, or ethylene, butene, hexene, 4-methyl-1-pentene Further, copolymers of the above-mentioned α-olefins with vinyl acetate and acrylic acid esters can be used, and those obtained by modifying these resins with unsaturated carboxylic acids or anhydrides thereof can also be used.

Examples of unsaturated carboxylic acids or anhydrides thereof include maleic acid, acrylic acid, methacrylic acid, crotonic acid, fumaric acid, itaconic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, ethyl acrylate, methacrylic acid. Methyl, ethyl maleate, acrylic acid-2-
Ethylhexyl, acrylamide, methacrylamide,
Palm oil fatty acid amide, maleimide and the like can be mentioned. Among them, particularly preferred are those obtained by modifying polypropylene with maleic anhydride in an amount of 0.05% by weight or more.

As the polyester resin of the resin (C), poly (ethylene terephthalate), poly (butylene terephthalate), poly (ethylene terephthalate)
Isophthalate), poly (ethylene glycol / cyclophthalate), poly (ethylene glycol / cyclohexane dimethanol / terephthalate), and the like. Representative examples thereof further include ethylene glycol, butylene glycol, and cyclohexanediene as copolymerization components. Diols such as methanol, neopentyl glycol and pentanediol, or isophthalic acid,
Benzophenone dicarboxylic acid, diphenyl sulfone dicarboxylic acid, diphenyl methane dicarboxylic acid, propylene bis (phenyl carboxylic acid), diphenyl oxide dicarboxylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, Those containing a dicarboxylic acid such as sabacic acid and diethylsuccinic acid can be used.

Of these resins (C), polyamide resins are most effective for improving heat resistance and hot water resistance.

(A) and (B) or (A) of the present invention
In the resin composition comprising (B) and (C), an antioxidant, a light stabilizer, a coloring agent, an ultraviolet absorber, a lubricant, a slip agent, an antistatic agent, and a plasticizer, as long as the invention is not impaired. , Various additives such as a crosslinking agent such as boric acid, an inorganic filler, an inorganic drying agent,
Various resins such as a superabsorbent resin may be blended. For example, the following is shown.

Stabilizers: metal salts of calcium stearate, hydrotalcites and the like. Antioxidants: 2,5-di-t-butylhydroquinone, 2,6-di-t-butyl-p-cresol, 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-t
-Butylphenol) and the like.

UV absorber: ethyl-2-cyano-3,
3'-diphenyl acrylate, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2-
(2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2-hydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy -4-octoxybenzophenone and the like.

Plasticizer: dimethyl phthalate, diethyl phthalate, dioctyl phthalate, wax, liquid paraffin, phosphate ester and the like.

Antistatic agents: pentaerythritol monostearate, sorbin monopalmitate, sulfated oleic acid, polyethylene oxide, carbon wax and the like. Lubricants: ethylene bisstearoid, butyl stearate and the like.

Colorant: carbon black, phthalocyanine, quinacridone, indoline, azo pigment, titanium oxide, red iron oxide, etc.

Filler: glass fiber, asbestos,
Mica, sericite, talc, glass flake, ballastonite, calcium silicate, aluminum silicate, montmorillonite, hectorite, beidellite, nontronite, saponite, sauconite, stevensite.

As a blending method for obtaining the composition of the present invention, a single-screw or twin-screw extruder (in the same direction or a different direction), a melt extruder using an intensive mixer, a continuous intensive mixer or the like, and pelletizing under cooling. A method is used.

The composition thus obtained is used alone or in combination with another thermoplastic resin to form a multilayer structure into sheets, films, bottles, cups and tubes.

When used as a film, it is used without stretching or stretching (uniaxial or biaxial stretching). When used as a multilayer film, it may be formed into a film by coextrusion, or a method such as ordinary dry lamination, wet lamination, extrusion lamination, or coating may be used later.

Before the above multilayering, aluminum,
A deposition film of silicon oxide, aluminum oxide, or the like can be formed by a known method.

In the case of multi-layering of sheets, bottles, cups and tubes, multi-layering is performed by co-extrusion molding, co-injection molding or the like, and then used after shaping into a desired shape.

The resin laminated on the composition layer of the present invention includes GI-PMMA, EVOH, polyolefin resin, polyamide resin, polyester resin, saturated polyester resin, polystyrene resin, polystyrene resin.
Polybutadiene block copolymer resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyurethane resin,
Polyvinyl acetate-based resins, polyacetal-based resins, and polycarbonate-based resins are exemplified. When obtaining a multilayer structure,
It may be preferable to use an adhesive resin in order to improve the adhesiveness of each layer. Here, as the adhesive resin, an olefin polymer or copolymer modified (added, grafted, etc.) with an unsaturated carboxylic acid or its anhydride (such as maleic anhydride) な ど polyethylene (low-density polyethylene, linear low- Density polyethylene), polypropylene, an ethylene-vinyl acetate copolymer, and an ethylene-acrylic acid ester｝ adhesive resin. These adhesive resins are used as an interlayer adhesive or by being compounded in each layer.

The composition of the present invention is not particularly limited, but when the composition of the present invention is X and the other resins are D, E and F, X / D, X
/ D / E, D / X / D, D / E / X / E / D, D / F /
E / X / E / F / D, D / E / X / E / D / E / X / E
/ D and the like. D, E, and F indicate different types of resin or a recovery layer, respectively. In particular, the barrier properties of the resin composition of the present invention depend on humidity, and it is preferable to arrange a multilayer structure so that the humidity is low. For example, the content is water (100% RH) and the storage atmosphere is 65%
In the case of RH, the lower the moisture permeability of the outer layer, the closer to 65% RH, the higher the barrier property. Also, in retort applications, even if the composition absorbs moisture during the retort, water is scattered during storage and the barrier properties are quickly restored.

In retort applications, the greater the difference in moisture permeability between the outer layer and the inner layer, the more water is scattered during storage even if the composition absorbs moisture in the retort, and the barrier property is recovered more quickly. Specifically, the moisture permeability of the outer layer is 40 g / m ² · day (40 ° C. 90
% RH) or more, and the inner layer preferably has a lower moisture permeability. Here, that the moisture permeability of the inner layer is lower than that of the outer layer means not only that the moisture permeability of the inner layer is less than 40 g / m ² · day, but also that the moisture permeability of the outer layer actually used is lower than that. means.

Specifically, a commercially available biaxially stretched polyamide film (15 μ) or a biaxially stretched polyester film (12 μ) has a moisture permeability of 260 g / m ² · da, respectively.
y is 50 g / m ² · day, which is preferable as the outer layer material. As the inner layer material, unstretched polyethylene (50
mu) and moisture permeability of each 9g / m ² · day of cast polypropylene (50.mu.), preferably a 7g / m ² · day, preferable in particular polypropylene is excellent in heat resistance.

The composition of the present invention has excellent gas barrier properties and, in addition, has not been found in conventional EVOH.
Because of its excellent heat resistance and hot water resistance, it can be used for ordinary food packaging, especially for containers, bags, pouches and container lids sealed by heat sealing, as well as materials for packaging containers for boiling and retort sterilized foods. Useful as It is also desirable for non-food packaging materials such as pharmaceuticals, agricultural chemicals, cosmetics, detergents, organic chemicals, audio components, stationery, and other non-food packaging materials.

In particular, the resin composition of the present invention is useful as a container for sterilizing boil and retort. Here, ordinary methods and conditions can be adopted for sterilizing boil and retort. For the retort treatment, a method such as a recovery type, a steam type, a shower type, and a spray type can be adopted.

[0048]

【Example】

Example 1 As an EVOH (A), an ethylene-vinyl acetate copolymer was saponified to obtain an ethylene content of 32 mol%.
99.5 mol% of saponification degree of vinyl acetate component, 2
80 parts by weight of a resin having an MFI of 7 g / 10 min at 50 ° C.
GI-PMMA (B) containing 24 mol% of a glutarimide unit represented by the formula (3) and having an MFI of 250 g at 5 ° C.
20 parts by weight of the resin for 10 minutes was melt-extruded at 250 ° C. by an extruder (L / D27) having a 40φ uniaxial full flight screw to obtain a blend pellet.

[0049]

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The GI-PMMA was copolymerized with methyl methacrylate and methacrylamide in a methanol solvent at 120 ° C. with addition of di-t-butyl peroxide and n-octyl mercaptan in an autoclave. Thereafter, a methanol solution of sodium methoxide is supplied and reacted to obtain the product.

Subsequently, after being melted at 250 ° C. by an extrusion film forming machine having a 40φ uniaxial full flight screw and a coat hanger die of 550 mm, cast on a cast roll at 98 ° C., a transparent unstretched film having a thickness of 15 μm was obtained. Obtained.

Next, the above film was used as an intermediate layer, and a commercially available biaxially stretched nylon-6 film (emblem manufactured by Unitika Ltd., thickness: 15 μm) as an outer layer, and a commercially available unstretched polypropylene film manufactured by Tocelo Co., Ltd. , RXC-1
1. A thickness of 70 μ｝ was selected, and A-385 / A-50 manufactured by Takeda Pharmaceutical Co., Ltd. was used as an adhesive for dry lamination (two-component type, urethane-based) at a solid content of 4 g /
After applying m ² and evaporating the solvent at 80 ° C., the above-mentioned composition film was laminated and aged at 40 ° C. for 5 days to obtain a multilayer film.

A caliber 10c made of polypropylene with water
m, the multilayer film was used as a cover material, and the polypropylene side of the film was used as an inner surface, and heat-sealed to the opening of the cup-shaped container to obtain a sealed container.

A retort apparatus {High temperature and high pressure cooking sterilization tester, RCS-40RTGN, manufactured by Hisaka Manufacturing Co., Ltd.}
, A retort treatment at 120 ° C. for 30 minutes was performed by a hot water heating method. Immediately after the retort treatment, the lid film had a white tint, but was completely transparent in about 30 minutes at 20 ° C. and 65% RH, and no other abnormalities in appearance were observed. Similarly, cut out the lid material from the retorted cup,
OXTRAN10 / 50A manufactured by MOCON
The oxygen permeation amount was measured at 65 ° C. on the oxygen gas side and 100% RH on the nitrogen gas side. 1.0c 12 hours after retort
It recovered to an equilibrium value of c / m ² · atm · day (hereinafter referred to as cc).

Comparative Example 1 EV used in Example 1 in place of the composition described in Example 1
A film was obtained in the same manner with OH alone, and the same test was carried out. As a result, after retorting, a portion where whitening did not recover and a wrinkled portion were found.

Comparative Example 2 EV used in Example 1 in place of the composition described in Example 1
80% by weight of OH and PMMA (MFI at 250 ° C. is 3 g /
Similarly, a blend pellet was obtained at 20% by weight (resin for 10 minutes), and a film was formed. A similar test was performed using this film. After the retort, a portion where the whitening did not recover and a wrinkled portion were observed.

Comparative Example 3 The blend ratio of EVOH and GI-PMMA described in Example 1 was 15% by weight and 85% by weight, respectively,
And a similar test was performed. After retort, the transparency was good, but the OTR was 4.0 cc, which was an insufficient barrier property.

Example 2 A test was conducted in the same manner as in Example 1 except that the blend ratio of EVOH and GI-PMMA was 60: 40% by weight. There is no problem in appearance after retort, and OTR is 1.
It was 7 cc.

Example 3 and Comparative Example 4 In Example 1, EVOH was prepared by mixing ethylene content of 38 mol%, saponification degree of 99 mol% and MFI at 250 ° C. of 35 g.
/ 10 minutes (2160 g), and the same test was conducted. No problem in appearance after retort, OT
R was 1.9 cc (Example 3)

The same raw materials were evaluated with the blending ratio being 15% by weight of EVOH and 85% by weight of GI-PMMA. The transparency after retorting was good, but the OTR was poor at 7.5 cc (Comparative Example). 4).

Comparative Example 5 EVOH (A) and GI-PMMA in Example 1
Same as above except that the mixing ratio of (B) was changed as shown in Table 1.
The test was carried out. Example 4 In Example 1, GI-PMMA was modified with a glutarimide group of the formula (4) by 20 mol%, and MFI at 250 ° C.
Was 1 g / 10 minutes (2160 g), and the same test was conducted. There was no problem in appearance after retort, and OTR was 1.0 cc.

[0062]

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Example 5 In Example 1, a film of 150 μm was obtained, and a film stretch tester × 6H type manufactured by Toyo Seiki Co., Ltd. was used.
At the same time, stretch 3.3 times vertically and 3.3 times horizontally at 150 ° C.
To obtain a 15 μm transparent film. continue,
Thereafter, retorting was performed in the same manner as in Example 1, but there was no problem in appearance, and the OTR was 0.7 cc.

Example 6 In Example 1, the outer layer was made of a biaxially stretched film polyester film (Lumirror manufactured by Toray Industries, Inc., 12 μm in thickness), and retorting was carried out in the same manner as in Example 1. No, OTR was 1.5cc.

Example 7 and Comparative Example 5 A co-extruded multilayer film consisting of four layers was obtained from the composition used in Example 1 by using a feed block type co-extrusion apparatus having four extruders and a T die. . The structure is polyamide from the outside. Novamid 10 manufactured by Mitsubishi Kasei Kogyo Co., Ltd.
20, thickness 20 μ｝, resin composition (X) (thickness 20
μ), adhesive resin ｛Admer QF manufactured by Mitsui Petrochemical Co., Ltd.
-500, thickness 10 µm, polypropylene {Mitsubishi Noblen PY-220 manufactured by Mitsubishi Yuka Co., Ltd., thickness 50 µm], and a transparent film. When this was retorted in the same manner as in Example 1, the transparency was completely restored as in the case of the dry laminating film, and the OTR was 0.6 cc (Example 7).

Similarly, when EV4H was used alone, the film did not recover from whitening after retort (Comparative Example 5).

Example 8 and Comparative Example 6 In Example 5, the structure was such that the polyamide thickness (100 μm) and the resin composition of Example 1 (thickness 150
μ), a maleic anhydride-modified polypropylene-based adhesive resin (thickness: 100 μ), and a multilayer sheet of polypropylene (thickness: 400 μ) were manufactured, and a vacuum pressure air molding machine (manufactured by Asano Manufacturing Co., Ltd.) was used. Round, top 3
A 7 mm round, 37 mm high cup was molded. Water was added thereto, and the lid was heat-sealed using the film of Example 1. The appearance after retort is no problem, and the OTR is 0.
It was 2 cc (Example 8). However, EVOH alone did not lose the whitening (Comparative Example 6).

Example 9 and Comparative Example 7 In the same manner as in Example 1, a film (outermost layer) of the composition (X) / polyethylene (TUX manufactured by Tocelo Co., Ltd.)
A two-layer film of -TC, 40 μ｝ film was obtained. After moisture conditioning at 20 ° C and 65% RH, the film contact surface was adjusted to 200 ° C by Fuji Impulse Sealer FR-450-5.
The film was sealed by setting the conditions of heating to such a degree that the polyethylene films were in contact with each other, and the polyethylene was sufficiently fused (JIS Z
The tensile test was performed at 0 kgf / 15 mm), and the appearance of the resin composition was not abnormal (Example 9).

When the EVOH alone / polyethylene multilayer film was heat-sealed in the same manner, the EVOH was melted and fused to the seal bar. In addition, waving due to shrinkage of EVOH was also observed (Comparative Example 7).

[0070]

[Table 1]

[0071]

【Example】

Example 2-1 As an EVOH (A), an ethylene-vinyl acetate copolymer was saponified to obtain an ethylene content of 32 mol%.
99.5 mol% of saponification degree of vinyl acetate component, 2
80% by weight of a resin having an MFI of 7 g / 10 min at 50 ° C.
As PA (C), a PA-6 / 12 copolymer (caprolactam unit and lauryl lactam unit having a weight ratio of 90 /
MFI was obtained by modifying the GI-PMMA (B) by 24 mol% as a GI-PMMA (B) with a glutarimide group represented by the following formula (3). 5 g / 10 min of the resin was added by 10 wt% to 40
The mixture was melt-extruded at 230 ° C. using an (L / D27) extruder having a φ uniaxial full flight screw to obtain a blend pellet.

Subsequently, the resin was melted at a resin temperature of 230 ° C. (discharge rate of 4 kg / hr) by an extrusion film forming machine having a 40φ uniaxial full flight screw and a coat hanger die of 550 mm, and then cast on a 98 ° C. cast roll. A transparent unstretched film having a thickness was obtained. Under these conditions, continuous operation for four consecutive days was possible. At this time, a schedule of assembling the apparatus on Monday and stopping on Friday can be adopted, so that it is sufficiently profitable. When the continuous operation is further performed, gel is frequently generated on the film membrane surface, and about 300
The number of gels of μ or more was 50/100 cm ² or more, which was a problem in quality.

Next, the above film was used as the intermediate layer, and the outer layer was a commercially available biaxially stretched nylon-6 film (emblem manufactured by Unitika Ltd., thickness 15 μm, moisture permeability 260 g / m ² · d).
ay} and a commercially available unstretched polypropylene film {RXC-11, manufactured by Tocello Co., Ltd., RXC-11, thickness 50 μm, moisture permeability 7 g / m ² · day} inside, and an adhesive for dry lamination (two-pack type, urethane A-385 / A-50 manufactured by Takeda Pharmaceutical Co., Ltd. as a solid content of 4 g /
After applying m ² and evaporating the solvent at 80 ° C., the above-mentioned composition film was laminated and aged at 40 ° C. for 5 days to obtain a multilayer film. At 20 ° C., the PA layer side 6
After humidity control under the conditions of 5% RH and 100% RH on the PP layer side,
It was mounted on CON OXTRAN10 / 50A and the oxygen gas permeation amount (OTR) was measured under the same conditions.
It was 0.7 cc / m ² · day · atm (hereinafter cc).

Using this film as a lid, the above multilayer film was selected in a polypropylene cup-shaped container containing water and adjusted to a 15% by weight toluene solution. The solution was heat-sealed with a heat sealer with the polypropylene side of the composite film as the inner surface to obtain a sealed container.

A retort apparatus {High temperature and high pressure cooking sterilization tester, RCS-40RTGN, manufactured by Hisaka Seisakusho Co., Ltd.}
Was used to carry out a retort treatment at 120 ° C. for 30 minutes. Immediately after the retort treatment, the lid film was white, but completely transparent in about 30 minutes at 20 ° C. and 65% RH, and no abnormality was observed in its external appearance.

The same container made separately was retorted, and immediately after the lid material was cut out, OXTRAN 10/50 manufactured by MOCON was used.
A, 65% RH on the PA layer side at 20 ° C, 1 on the PP layer side
The OTR was measured under the condition of 00% RH. Immediately after 40cc
However, after about 12 hours, it recovered to 0.8 cc.

Comparative Example 2-1 A film was obtained in the same manner as in Example 2-1, using EVOH alone as described in Example 2-1, and the same test was conducted. The same test was carried out. Parts,
Wrinkled parts were seen.

Comparative Example 2-2 In Example 2-1 the composition was changed to EV described in Example 2-1.
OH was 80% and PA was 20%, and a film was formed in the same manner. The number of gels was 50 pieces / 100 cm ² or more.
Days later. Using this film, retorting was performed in the same manner. Although the appearance was fine, the OTR recovered only up to 1.2 cc (before retort, it was 0.1 cc).
9cc).

Examples 2-2 to 2-6, Comparative Examples 2-3 and 2
-4 In Example 1, the blend ratio and the type were changed, but there was no problem in appearance, and the oxygen gas permeation amount was restored to a value close to the value before retort (Examples 2 to 4). 6). However, when the blending ratio of B or C was low, the recovery of the barrier property was insufficient (Comparative Examples 2-3 and 2-4).

Example 2-7 In place of GI-PMMA of Example 2-1 (4), GI-PMMA modified with 20% by mole of glutarimide represented by the formula (Formula 4) was used. An evaluation was performed. The appearance after retort was no problem, and the OTR recovered to 0.9cc.

Comparative Example 2-5 In Example 2-1, the composition was changed to EV described in Example 2-1.
OH was 15% and GI-PMMA of Example 2-7 was 85%. Although there was no problem in appearance, the OTR recovered only up to 4.0 cc.

Example 2-8 In Example 2-1, a film of 150 μm was obtained, and a film stretch tester × 6H type manufactured by Toyo Seiki Co., Ltd. was used.
Simultaneously stretched 3.3 times vertically and 3.3 times horizontally at 80 ° C.
It was heat-set at 0 ° C. to obtain a 15 μm transparent film. Subsequently, retort was performed in the same manner as in Example 2-1.
There were no appearance problems. The OTR equilibrium values before and after the retort were 0.4 and 0.5 cc, respectively.

Example 2-8 The same procedure as in Example 2-1 was carried out except that the outer layer was a biaxially stretched polyester film 1 (Lumirror, manufactured by Toray Industries, Inc., thickness: 12
The retort was carried out in the same manner as in Example 1 with μ｝, but there was no problem in appearance.

Example 2-9 and Comparative Examples 2-6 and 2-7 Using the composition used in Example 2-1 and a feedblock type coextrusion apparatus having four extruders and a T die. A coextruded multilayer film consisting of four layers was obtained. From the outside, polyamide {Novamid 1020 manufactured by Mitsubishi Kasei Kogyo Co., Ltd., thickness 20μ}, resin composition (thickness 20μ),
Adhesive resin: Admer QF-50 manufactured by Mitsui Petrochemical Co., Ltd.
0, thickness 10 μ｝, polypropylene {Mitsubishi Noblen PY-220 manufactured by Mitsubishi Yuka Co., Ltd., thickness 50 μ｝, and a transparent film. When this was retorted in the same manner as in Example 1, the transparency was completely restored as in the case of the dry lami film, and the equilibrium OTR after retorting was 0.6 cc (Example 2-9).

Similarly, the experiment was carried out using the resins of Comparative Examples 2-2 and 2-3, but the film did not recover from whitening after retort (Comparative Examples 2-6 and 2-7, respectively).

Example 2-10 and Comparative Example 2-9 In Example 2-9, the structure was changed from the outside to polyamide (thickness 100 μm), resin composition (D) (thickness 50 μm),
Adhesive resin (thickness 100μ), polypropylene (thickness 4
00μ) multilayer sheet, using a vacuum pressure molding machine {manufactured by Asano Co., Ltd.}
, A cup with a top surface of 37 mm and a height of 37 mm was molded. Water was added thereto, and the lid was heat-sealed using the film of Example 1. The appearance after the retort was no problem, and the OTR after the retort was 0.2 cc (Example 2-10).

However, the OTR after retort was 0.4 in the resin composition comprising two components, EVOH and PA (Comparative Example 2-9).

[0088]

[Table 2]

[0089]

Industrial Applicability The resin composition of the present invention has excellent heat resistance and hot water resistance, and also has excellent gas barrier properties and moldability. Therefore, food packaging, especially packaging in which EVOH is used as the outermost layer, is provided. Or for packaging retort foods. The resin composition of the present invention has excellent heat resistance and hot water resistance, has excellent moldability capable of performing molding for a long time, and has little deterioration in gas barrier properties due to retort. Therefore, it is useful for food packaging, especially for retort food packaging.

Continuing from the front page (72) Inventor Shiro Nagata 1-12-39 Umeda, Kita-ku, Osaka City Inside Kuraray Co., Ltd. (72) Inventor Yoshifumi Murata 2-28 Kurashiki-cho, Nakajo-cho, Kitakanbara-gun, Niigata Kuraray Co., Ltd. Examiner: Shoko Mitani (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 23/26 B32B 27/32

Claims (3)

(57) [Claims] 1. A modified acrylic resin (B) containing from 97 to 50% by weight of a saponified ethylene-vinyl ester copolymer (A) and at least 2 mol% of glutarimide units.
A resin composition comprising 50% by weight. 2. A modified acrylic resin (B) 3-47 containing 94 to 50% by weight of a saponified ethylene-vinyl ester copolymer (A) and at least 2 mol% of a glutarimide unit.
% By weight , and 3 to 47% by weight of the polyamide (C) . 3. The resin set according to claim 1, wherein said intermediate layer is a resin set.
Biaxially stretched polyamide film with a composite layer and outer layer
Or biaxially stretched polyester film and no inner layer
Stretched polyethylene film or unstretched polypropylene
A multilayer package having a film.