JP2001080004A - Laminated film and container using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated film excellent in gas barrier properties, deodorizing properties and heat resistance and easy in post treatment after use and a container using this laminated film. SOLUTION: A laminated film [1] is constituted of a film comprising a liquid crystal polymer showing optical anisotropy at a time of melting and a film comprising polyacrylonitrile or a laminated film [2] is constituted of the film comprising the liquid crystal polymer showing optical anisotropy at a time of melting, the film comprising polyacrylonitrile and a film comprising a thermoplastic resin (excepting the liquid crystal polymer and polyacrylonitrile). A container is formed by using the laminated film [1] or [2].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated film which is excellent in gas barrier properties, deodorant properties, heat resistance and the like, and which does not generate ash even when burned after use, and a container using the laminated film.

[0002]

2. Description of the Related Art Conventionally, aluminum foil, resin films, and the like have been used as packaging materials for various foods, beverages, pharmaceuticals, toiletries, and the like. However, when aluminum foil is used as such a wrapping material, a metal detector cannot be applied in the manufacturing process during product quality control, the product cannot be heated in a microwave oven, The market has pointed out problems such as the occurrence of problems. On the other hand, when a resin film is used as a wrapping material, the gas barrier properties of the resin film are insufficient, or the gas barrier properties usually decrease even at high temperatures or high humidity even if the gas barrier properties are high. Markets have pointed out problems such as insufficient resistance and chemical resistance, and odors leaking out of the packaging material when a cataplasm is packaged. On the other hand, when vinyl chloride, vinylidene chloride, or the like is used for the laminated film, there is also a problem that a gas containing chlorine is generated during the combustion. As an example of study on a conventional film, see, for example, JP-A-6-15653.
No. 1 discloses a laminated film composed of a stretched polyethylene layer and a paper layer, but has a problem that gas barrier properties and the like are insufficient. In addition, Japanese Patent Application Laid-Open No. 6-24746
No. 7 discloses a laminated film composed of a layer formed of metal vapor deposition or a metal pigment, a nylon layer, and a heat seal layer, but the gas barrier properties, the deodorant properties, etc. are not sufficient. There are problems such as occurrence. On the other hand, polyacrylonitrile has a very small amount of adsorbed medicinal components such as 1-menthol and methyl salicylate, and is suitable as a packaging material for the medicinal components.
TECH JAPAN (1987) VOL 3 NO
5 P483, "Packaging technology" December 1997 issue, P1
151, etc. However, when polyacrylonitrile is used as a packaging material, the polyacrylonitrile has insufficient gas barrier properties, water vapor barrier properties, particularly gas barrier properties at high temperatures and / or high humidity, insufficient water vapor barrier properties, and chemical resistance. It was pointed out by the market that the properties were not sufficient, and improvement was requested. For example, JP-A-2-260945 describes a laminated film of a film made of polyester, polyacrylonitrile, ethylene-vinyl acetate, and the like and a polyolefin film. However, gas barrier properties, heat resistance, chemical resistance, and the like are described. Was not enough. In addition, liquid crystal polymers have been studied for film formation because of their excellent heat resistance, gas barrier properties, chemical resistance and the like, but on the other hand, heat sealing properties and the like were insufficient. For example, JP-A-8
-283441 discloses a laminated film composed of a liquid crystalline polymer and a thermoplastic resin,
No mention is made of deodorant properties, in particular, deodorant properties against medicinal components of poultices.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a laminated film which is excellent in gas barrier properties, deodorant properties and heat resistance and which can be easily post-processed after being used, and a container using the laminated film. It is in.

[0004]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve such problems, and as a result, have found that a liquid crystal polymer layer and a layer made of polyacrylonitrile exhibiting optical anisotropy when melted. The inventors have found that the laminated film thus constituted solves the above-mentioned problem, and have reached the present invention. That is, the present invention relates to [1] a laminated film comprising a film composed of a liquid crystalline polymer exhibiting optical anisotropy when melted and a film composed of polyacrylonitrile as constituent components. Further, the present invention provides [2] a film made of a liquid crystalline polymer exhibiting optical anisotropy when melted, a film made of polyacrylonitrile, and a film made of a thermoplastic resin (however, excluding the liquid crystalline polymer and polyacrylonitrile) Is a component of the laminated film. Further, the present invention relates to [3] a container using the laminated film according to [1] or [2].

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. Various liquid crystalline polymers exhibiting optical anisotropy when melted are known, and examples thereof include wholly aromatic polyesters, polyimides, polyesteramides, and resin compositions containing them. In the present invention, the liquid crystalline polymer is preferably a liquid crystalline polyester or a composition containing the liquid crystalline polyester. In view of the moldability and the performance of the resulting film, (A) the liquid crystalline polyester is preferably a continuous phase. It is more preferable to use (B) a liquid crystal polyester resin composition having a copolymer having a functional group reactive with the liquid crystal polyester as a dispersed phase.

[0006] The liquid crystal polyester referred to here is a polyester called a thermotropic liquid crystal polymer.
Specifically, (1) a combination of an aromatic dicarboxylic acid, an aromatic diol and an aromatic hydroxycarboxylic acid, (2) a combination of different aromatic hydroxycarboxylic acids, and (3) an aromatic hydroxycarboxylic acid Consisting of a combination of an aromatic dicarboxylic acid and a nucleus-substituted aromatic diol, (4)
Examples thereof include those obtained by reacting an aromatic hydroxycarboxylic acid with a polyester such as polyethylene terephthalate and the like, which form an anisotropic melt at a temperature of 400 ° C. or lower. In addition, in place of these aromatic dicarboxylic acids, aromatic diols, and aromatic hydroxycarboxylic acids, ester-forming derivatives thereof may be used.

The repeating structural units of the liquid crystal polyester include the following repeating structural units derived from an aromatic dicarboxylic acid, the following repeating structural units derived from an aromatic diol,
Examples of the repeating structural unit derived from an aromatic hydroxycarboxylic acid include, but are not limited to, these.

A repeating structural unit derived from an aromatic dicarboxylic acid:

[0009]

A repeating structural unit derived from an aromatic diol:

[0011]

A repeating structural unit derived from an aromatic hydroxycarboxylic acid:

A liquid crystal polyester which is particularly preferable from the balance of heat resistance, mechanical properties and workability is More preferably at least 30 mol% of the total number of the repeating structural units.
The above is included. Specifically, the combination of repeating structural units is preferably any one of the following (I) to (VI).

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

The production method of the liquid crystal polyesters (I) to (VI) is described in, for example, JP-B-47-47870.
JP-B-63-3888, JP-B-63-3891, JP-B-56-18016, JP-A-2-51
No. 523, etc. Of these, a combination of (I), (II) or (IV) is preferable, and a combination of (I) or (II) is more preferable.

In the field in which high heat resistance is required in the liquid crystal polyester resin composition of the present invention, the liquid crystal polyester of the component (A) contains 30 to 80 mol% of the following repeating unit (a '), A liquid crystal polyester in which b ′) is 0 to 10 mol%, the repeating unit (c ′) is 10 to 25 mol%, and the repeating unit (d ′) is 10 to 35 mol% is preferably used.

[0022] (In the formula, Ar is a divalent aromatic group.)

The field in which the laminated film of the present invention requires easy disposal such as incineration after use from the viewpoint of environmental problems is particularly preferable among the preferable combinations of the fields required so far. Liquid crystal polyesters comprising a combination of only carbon, hydrogen and oxygen are particularly preferably used.

The component (B) used in the liquid crystal polyester resin composition of the present invention is a copolymer having a functional group reactive with the liquid crystal polyester. The functional group having reactivity with the liquid crystal polyester may be anything as long as it has reactivity with the liquid crystal polyester, and specifically, includes an oxazolyl group, an epoxy group, an amino group, etc., and is preferably an epoxy group. . The epoxy group or the like may be present as a part of another functional group, and such an example includes a glycidyl group.

In the copolymer (B), the method for introducing the functional group into the copolymer is not particularly limited, and it can be carried out by a known method. For example, at the stage of synthesizing the copolymer, it is possible to introduce the monomer having the functional group by copolymerization, or it is also possible to graft copolymerize the monomer having the functional group to the copolymer. It is.

As a monomer having a functional group reactive with the liquid crystal polyester, and particularly as a monomer having a glycidyl group, unsaturated glycidyl carboxylate and / or unsaturated glycidyl ether are preferably used.

The unsaturated carboxylic acid glycidyl ester is
Preferably a general formula (R ₁ has 2 to ₁₃ carbon atoms having an ethylenically unsaturated bond.
Is a hydrocarbon group. And the unsaturated glycidyl ether is preferably a compound represented by the general formula: (R ₂ has 2 to 18 carbon atoms having an ethylenically unsaturated bond.
A hydrocarbon group, X is -CH ₂ -O- or It is. ).

Specifically, examples of the unsaturated glycidyl carboxylate include glycidyl acrylate, glycidyl methacrylate, diglycidyl itaconate,
Examples thereof include butenetricarboxylic acid triglycidyl ester and p-styrenecarboxylic acid glycidyl ester.
Examples of the unsaturated glycidyl ether include vinyl glycidyl ether, allyl glycidyl ether, 2-methylallyl glycidyl ether, methacryl glycidyl ether, and styrene-p-glycidyl ether.

The copolymer (B) having a functional group reactive with the liquid crystal polyester preferably contains 0.1 to 30% by weight of an unsaturated carboxylic acid glycidyl ester unit and / or an unsaturated glycidyl ether unit. It is a copolymer containing.

The copolymer (B) having a functional group reactive with the liquid crystal polyester may be a thermoplastic resin or a rubber, or a mixture of a thermoplastic resin and a rubber. You may. A rubber having excellent thermal stability and flexibility of a molded product such as a film or sheet obtained by using the liquid crystal polyester resin composition is more preferable.

More preferably, the copolymer (B) having a functional group reactive with the liquid crystal polyester is
A copolymer having a heat of fusion of crystal of less than 3 J / g. The copolymer (B) preferably has a Mooney viscosity of 3 to 70, more preferably 3 to 30 and more preferably 4 to 30.
25 are particularly preferred. The Mooney viscosity as used herein refers to a value measured at 100 ° C. using a large rotor according to JIS K6300. Outside these ranges, the thermal stability and flexibility of the composition may decrease.

The rubber mentioned here corresponds to a polymer substance having rubber elasticity at room temperature according to a new edition of Polymer Dictionary (edited by the Society of Polymer Science, published in 1988, Asakura Shoten).
Specific examples thereof include natural rubber, butadiene polymer, butadiene-styrene copolymer (including random copolymer, block copolymer (including SEBS rubber or SBS rubber, etc.), and graft copolymer). The hydrogenated product, isoprene polymer, chlorobutadiene polymer, butadiene-acrylonitrile copolymer, isobutylene polymer, isobutylene-butadiene copolymer rubber, isobutylene-isoprene copolymer, acrylate-ethylene copolymer rubber , Ethylene-propylene copolymer rubber, ethylene-butene copolymer rubber, ethylene-propylene-styrene copolymer rubber, styrene-
Isoprene copolymer rubber, styrene-butylene copolymer, styrene-ethylene-propylene copolymer rubber, perfluoro rubber, fluoro rubber, chloroprene rubber, butyl rubber, silicone rubber, ethylene-propylene-non-conjugated diene copolymer rubber, Examples include thiol rubber, polysulfide rubber, polyurethane rubber, polyether rubber (eg, polypropylene oxide), epichlorohydrin rubber, polyester elastomer, polyamide elastomer, and the like. Among them, acrylate-ethylene copolymers are preferably used, and (meth) acrylate-
Ethylene copolymer rubber is more preferred.

These rubber-like substances are produced by any production method (eg, emulsion polymerization method, solution polymerization method, etc.) and any catalyst (eg, peroxide, trialkylaluminum, lithium halide, nickel-based catalyst, etc.). It may be something.

In the present invention, the copolymer (B)
Is a rubber having a functional group reactive with the liquid crystal polyester in the rubber as described above. In such a rubber, a method for introducing a functional group reactive with the liquid crystal polyester into the rubber is not particularly limited, and can be performed by a known method.
For example, it is possible to introduce the monomer having the functional group by copolymerization at the stage of synthesizing the rubber, or it is also possible to graft copolymerize the monomer having the functional group to the rubber.

As specific examples of the copolymer (B) having a functional group reactive with the liquid crystal polyester, rubbers having an epoxy group include (meth) acrylate-ethylene- (unsaturated glycidyl carboxylate and And / or unsaturated glycidyl ether) copolymer rubber.

Here, the (meth) acrylic acid ester is
An ester obtained from acrylic acid or methacrylic acid and an alcohol. Alcohols have 1 carbon atom
~ 8 alcohols are preferred. Specific examples of (meth) acrylates include methyl acrylate, methyl methacrylate, n-butyl acrylate, n-butyl methacrylate, tert-butyl acrylate, ter
Examples thereof include t-butyl methacrylate, 2-ethylhexyl acrylate, and 2-ethylhexyl methacrylate. As the (meth) acrylic acid ester, one kind thereof may be used alone, or two or more kinds may be used in combination.

Preferably, the (meth) acrylic acid ester unit is more than 40% by weight and less than 97% by weight, more preferably 45 to 70% by weight, and the ethylene unit is 3% by weight to 5% by weight.
0% by weight, more preferably 10 to 49% by weight, 0.1 to 30% by weight of unsaturated carboxylic acid glycidyl ether unit and / or unsaturated glycidyl ether unit,
More preferably, it is 0.5 to 20% by weight. If the ratio is outside the above range, the resulting molded article such as a film or sheet may have insufficient thermal stability and mechanical properties.

The copolymer rubber can be produced by a conventional method, for example, bulk polymerization, emulsion polymerization, solution polymerization or the like using a free radical initiator. Typical polymerization methods are described in JP-B-46-45085 and JP-B-6-45085.
No. 1-127709, pressure of 500 k in the presence of a polymerization initiator generating free radicals
g / cm ² or more and a temperature of 40 to 300 ° C.

Other rubbers that can be used in the copolymer (B) of the present invention include acrylic rubber having a functional group reactive with liquid crystal polyester, and vinyl aromatic having a functional group reactive with liquid crystal polyester. Hydrocarbon compounds
A conjugated diene compound block copolymer rubber can also be exemplified.

The acrylic rubber mentioned here is preferably represented by the general formula (1) (In the formula, R ¹ represents an alkyl group having 1 to 18 carbon atoms or a cyanoalkyl group.), A general formula (2) (Wherein, R ² is an alkylene group having 1 to 12 carbon atoms, R ³
Represents an alkyl group having 1 to 12 carbon atoms. ) And general formula (3) (Wherein R ⁴ is a hydrogen atom or a methyl group, R ⁵ is an alkylene group having 3 to 30 carbon atoms, and R ⁶ is a 1 to 20 carbon atom.
Wherein n represents an integer of 1 to 20; )) At least one monomer selected from the compounds represented by the formula (1).

Specific examples of the alkyl acrylate represented by the general formula (1) include, for example, methyl acrylate, ethyl acrylate, propyl acrylate,
Examples thereof include butyl acrylate, pentyl acrylate, hexyl acrylate, actyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, dodecyl acrylate, and cyanoethyl acrylate.

The alkoxyalkyl acrylate represented by the general formula (2) includes, for example, methoxyethyl acrylate, ethoxyethyl acrylate, butoxyethyl acrylate, ethoxypropyl acrylate and the like. One or more of these can be used as the main component of the acrylic rubber.

As a constituent of the acrylic rubber, an unsaturated monomer copolymerizable with at least one monomer selected from the compounds represented by the above general formulas (1) to (3), if necessary. Can be used. Examples of such unsaturated monomers include styrene, α-methylstyrene, acrylonitrile, halogenated styrene, methacrylonitrile, acrylamide, methacrylamide, vinylnaphthalene, N-methylolacrylamide, vinyl acetate, vinyl chloride, chloride Vinylidene, benzyl acrylate, methacrylic acid, itaconic acid, fumaric acid, maleic acid and the like.

The preferred constituent ratio of the acrylic rubber having a functional group reactive with the liquid crystal polyester is at least one monomer selected from the compounds represented by the above general formulas (1) to (3). 0 to 99.9% by weight, 0.1 to 30.0% by weight of unsaturated carboxylic acid glycidyl ester and / or unsaturated glycidyl ether, selected from the compounds represented by the above general formulas (1) to (3). Unsaturated monomer copolymerizable with at least one monomer 0.0
３30.0% by weight. When the constituent ratio of the acrylic rubber is within the above range, heat resistance and impact resistance of the composition,
The molding processability is good and preferable.

The method for producing the acrylic rubber is not particularly limited. For example, JP-A-59-113010, JP-A-62-64809, and JP-A-3-160008.
Or a well-known polymerization method described in WO95 / 04764 or the like, and can be produced by emulsion polymerization, suspension polymerization, solution polymerization or bulk polymerization in the presence of a radical initiator. .

The vinyl aromatic hydrocarbon compound-conjugated diene compound block copolymer rubber having a functional group reactive with the liquid crystal polyester is preferably
Rubber obtained by epoxidizing a block copolymer consisting of (a) a sequence mainly composed of a vinyl aromatic hydrocarbon compound and (b) a sequence mainly composed of a conjugated diene compound, or a hydrogenated product of the block copolymer Is a rubber obtained by epoxidation of

The vinyl aromatic hydrocarbon compound-conjugated diene compound block copolymer or its hydrogenated product can be produced by a known method, for example, Japanese Patent Publication No. 40-23.
798 and JP-A-59-133203.

As the aromatic hydrocarbon compound, for example,
Styrene, vinyltoluene, divinylbenzene, α-methylstyrene, p-methylstyrene, vinylnaphthalene and the like can be mentioned, among which styrene is preferable.
Examples of the conjugated diene compound include butadiene, isoprene, pyrrylene, 1,3-pentadiene, 3-butyl-1,3-octadiene and the like, butadiene or isoprene is preferred.

The rubber used as the copolymer (B) is preferably (meth) acrylate-ethylene-
(Unsaturated carboxylic acid glycidyl ester and / or unsaturated glycidyl ether) copolymer rubber is used.

The rubber used as the copolymer (B) can be vulcanized as required and used as a vulcanized rubber. The above (meth) acrylic acid ester-ethylene-
Vulcanization of the (unsaturated carboxylic acid glycidyl ester and / or unsaturated glycidyl ether) copolymer rubber is achieved by using a polyfunctional organic acid, a polyfunctional amine compound, an imidazole compound, and the like. It is not limited.

Further, as a specific example of the copolymer (B) having a functional group reactive with the liquid crystal polyester, the thermoplastic resin having an epoxy group includes (a) 50 to 99% by weight of ethylene units, (b) ) 0.1 to 30% by weight, preferably 0.5 to 20% by weight of unsaturated carboxylic acid glycidyl ester units and / or unsaturated glycidyl ether units.
% By weight, and (c) an epoxy group-containing ethylene copolymer having an ethylenically unsaturated ester compound unit of 0 to 50% by weight.

Examples of the ethylenically unsaturated ester compound (c) include vinyl carboxylate such as vinyl acetate, vinyl propionate, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate and butyl methacrylate. Esters, α, β-unsaturated carboxylic acid alkyl esters, and the like. Particularly, vinyl acetate, methyl acrylate and ethyl acrylate are preferred.

Specific examples of the epoxy group-containing ethylene copolymer include, for example, a copolymer composed of ethylene units and glycidyl methacrylate units, a copolymer composed of ethylene units and glycidyl methacrylate units, and a methyl acrylate unit. Copolymers composed of glycidyl methacrylate units and ethyl acrylate units, and copolymers composed of ethylene units, glycidyl methacrylate units and vinyl acetate units are exemplified.

The melt index of the epoxy group-containing ethylene copolymer (hereinafter sometimes referred to as MFR. JI
SK6760, 190 ° C, 2.16 kg load) is preferably 0.5 to 100 g / 10 min, more preferably 2 to 100 g / 10 min.
５０50 g / 10 min. The melt index may be outside this range, but the melt index is 100 g
If it exceeds / 10 minutes, it is not preferable in view of the mechanical properties of the composition, and if it is less than 0.5 g / 10 minutes, the component (A)
Is inferior in compatibility with the liquid crystal polyester.

[0055] Also, the epoxy group-containing ethylene copolymer is preferably in the range stiffness modulus of 10~1300kg / cm ^2, further preferably from 20~1100kg / cm ^2. If the flexural rigidity is outside this range, the moldability and mechanical properties of the composition may be insufficient.

The epoxy group-containing ethylene copolymer is usually prepared by reacting an unsaturated epoxy compound and ethylene in the presence of a radical generator at 500 to 4000 atm and 100 to 300 ° C. in the presence or absence of a suitable solvent or chain transfer agent. It is produced by a high-pressure radical polymerization method in which copolymerization is carried out in the presence. It can also be produced by a method in which an unsaturated epoxy compound and a radical generator are mixed with polyethylene and melt-grafted and copolymerized in an extruder.

The liquid crystal polyester resin composition mentioned as a preferred specific example of the liquid crystalline polymer used in the present invention is a copolymer having (A) a liquid crystal polyester as a continuous phase and (B) a functional group reactive with the liquid crystal polyester. Is a resin composition having a dispersed phase. When the liquid crystal polyester is not a continuous phase, the gas barrier properties and heat resistance of a molded article such as a film or a sheet using the liquid crystal polyester resin composition are significantly reduced, which is not preferable.

The details of the mechanism of the resin composition of such a copolymer having a functional group and the liquid crystal polyester are not clear, but the composition between the component (A) and the component (B) is not clear. It is considered that a reaction occurs, and the component (A) forms a continuous phase, and the component (B) is finely dispersed, thereby improving the moldability of the composition.

One embodiment of the liquid crystal polyester resin composition comprises (A) 56.0 to 99.9% by weight, preferably 65.0 to 99.9% by weight, more preferably 70 to 98% by weight of the liquid crystal polyester. And (B) a copolymer having a functional group reactive with the liquid crystal polyester 44.0 to 44.0.
The resin composition contains 0.1% by weight, preferably 35.0 to 0.1% by weight, and more preferably 30 to 2% by weight. If the content of the component (A) is less than 56.0% by weight, the gas barrier properties and heat resistance of a molded article such as a film or sheet obtained from the composition may be undesirably reduced.
On the other hand, if the content of the component (A) exceeds 99.9% by weight, the molding processability of the composition may be reduced, and the composition is expensive, which is not preferable.

As a method for producing the liquid crystal polyester resin composition, a known method can be used. For example, there is a method in which each component is mixed in a solution state and the solvent is evaporated or precipitated in the solvent. From an industrial point of view, a method of kneading each component in a molten state is preferred. For the melt kneading, kneading apparatuses such as a single-screw or twin-screw extruder and various kneaders which are generally used can be used. In particular, a biaxial high kneader is preferred. During the melt kneading, the cylinder set temperature of the kneading apparatus is 200 to 36.
The temperature range is preferably 0 ° C, more preferably 230 to 35.
0 ° C.

At the time of kneading, the respective components may be previously mixed uniformly using a device such as a tumbler or a Henschel mixer, or if necessary, the mixing may be omitted, and each component may be separately supplied to the kneading device. Methods can also be used.

In the liquid crystalline polymer used in the present invention, if necessary, an organic filler, an antioxidant, a heat stabilizer, a light stabilizer, a flame retardant, a lubricant, an inorganic or organic colorant, a rust inhibitor Various additives such as a crosslinking agent, a foaming agent, a fluorescent agent, a surface smoothing agent, a surface gloss improving agent, and a mold release improving agent such as a fluororesin can be added during the manufacturing process or in the subsequent processing process.

As the layer composed of the liquid crystalline polymer used in the present invention, the liquid crystalline polymer may be formed by, for example, extruding and winding the molten resin from a T die, or forming the molten resin into a cylindrical shape by an extruder provided with an annular die. The film or sheet obtained by the inflation film forming method, the film or sheet obtained by the hot press method or the solvent casting method, or the sheet obtained by the injection molding method or the extrusion method is further uniaxially stretched. Alternatively, a film or sheet obtained by biaxial stretching can be used. In the case of injection molding, extrusion molding, or the like, a film or sheet can be obtained by dry blending and pelletizing the component pellets at the time of molding without going through a kneading step in advance.

In the T-die method, a uniaxially stretched film or a biaxially stretched film obtained by winding a molten resin extruded through a T-die while stretching it in the machine direction (longitudinal direction) is preferably used.

The setting conditions of the extruder at the time of forming the uniaxially stretched film can be appropriately set according to the composition of the composition, but the cylinder setting temperature is preferably in the range of 200 to 370 ° C., and more preferably in the range of 230 to 350 ° C. More preferred. If the ratio is outside this range, thermal decomposition of the composition may occur or film formation may be difficult, which is not preferable.

The slit interval of the T die is 0.2 to 2.0.
mm is preferable, and 0.2 to 1.2 mm is more preferable. The draft ratio of the uniaxially stretched film is preferably in the range of 1.1 to 40, more preferably 10 to 40, and particularly preferably 15 to 35.

Here, the draft ratio is a value obtained by dividing the cross-sectional area of the T-die slit by the cross-sectional area of the film perpendicular to the longitudinal direction. If the draft ratio is less than 1.1, the film strength is insufficient, and if the draft ratio exceeds 45, the surface smoothness of the film may be insufficient, which is not preferable. The draft ratio can be set by controlling the setting conditions of the extruder, the winding speed, and the like.

For the biaxially stretched film, the same extruder setting conditions as those for forming the uniaxially stretched film, that is, the cylinder set temperature is preferably in the range of 200 to 370 ° C., more preferably 230 to 350 ° C. The composition is melt-extruded at a slit interval of preferably 0.2 to 1.2 mm, and the melt sheet extruded from the T-die is simultaneously stretched in the longitudinal direction and the direction perpendicular to the longitudinal direction (lateral direction). The method or the melt sheet extruded from the T-die is first stretched in the longitudinal direction, and then this stretched sheet is subjected to 100 to 350 ° C., preferably 200 to 33 ° C. in the same step.
It can be obtained by, for example, a successive stretching method in which the film is stretched in the lateral direction from a tenter at a high temperature (atmosphere) of 0 ° C.

When a biaxially stretched film is obtained, the stretching ratio is preferably in the range of 1.2 to 20 times in the longitudinal direction and 1.2 to 20 times in the transverse direction. If the stretching ratio is outside the above range, the strength of the composition film may be insufficient, or it may be difficult to obtain a film having a uniform thickness.

An inflation film obtained by forming a melt sheet extruded from a cylindrical die by inflation is also preferably used.

That is, the liquid crystal polyester resin composition obtained by the above method was supplied to a melt kneading extruder equipped with a die having an annular slit, and was set at a cylinder set temperature of 20.
Melt kneading is performed at 0 to 370 ° C, preferably 230 to 360 ° C, and the molten resin is extruded upward or downward from the annular slit of the extruder. The interval between the annular slits is usually 0.1 to 5 mm, preferably 0.2 to 2 mm, and the diameter of the annular slit is usually 20 to 1000 mm, preferably 25 to 600 mm.

Draft is applied to the melt-extruded molten resin film in the longitudinal direction (MD), and air or an inert gas, for example, nitrogen gas is blown from the inside of the cylindrical film to thereby obtain a transverse direction perpendicular to the longitudinal direction. The film is expanded and stretched in (TD).

In inflation molding (film formation),
The preferred blow ratio is 1.5 to 10, and the preferred MD draw ratio is 1.5 to 40. If the setting conditions during the inflation film formation are outside the above range, it may be difficult to obtain a high-strength liquid crystal polyester resin composition film having a uniform thickness and no wrinkles.

The expanded film is usually air-cooled or water-cooled on its circumference, and then passed through a nip roll and taken up.

In the case of inflation film formation, conditions can be selected according to the composition of the liquid crystal polyester resin composition such that the cylindrical molten film expands to a uniform thickness and a smooth surface state. The thickness of the layer composed of the liquid crystalline polymer in the present invention is not particularly limited, but is preferably 3 to 1000 μm, more preferably 3 to 500 μm.
It is.

In the present invention, another component of the laminated film is a film made of polyacrylonitrile. Here, polyacrylonitrile is a copolymer containing acrylonitriles such as acrylonitrile and methacrylonitrile as main monomers in an amount of 50% or more, and copolymerized with comonomers such as styrene, acrylic acid, acrylic ester, methacrylic acid, and methacrylic ester. A mixture in which the copolymer resin is a continuous phase and an elastic body such as a butadiene copolymer is a dispersed phase is also included in this category. Here, preferred examples of the elastic body include polybutadiene, a styrene-butadiene copolymer, an acrylonitrile-butadiene copolymer, and polyisoprene.

In the laminated film of the present invention, it is preferable that the film made of polyacrylonitrile is a heat-sealing layer from the viewpoints of weight reduction, deodorizing effect, and cost reduction of the laminated film. In the package, by using a laminated film having a film made of polyacrylonitrile as a heat sealing layer, the flavor adsorption is small, especially 1-menthol, and when the medicinal component of a volatile cataplasm such as methyl salicylate is a content. Furthermore, a package having a large deodorizing effect can be obtained.

When the outer layer of the package is a film made of a liquid crystalline polymer, the liquid crystalline polymer also has a deodorizing property, so that a package having a further deodorizing effect can be obtained. Further, when the film made of the liquid crystalline polymer is used as the outer layer, the penetration of oxygen, water vapor and the like from the outside is largely prevented, and the effect of preventing alteration of the contents is extremely large. Further, by using a film made of the liquid crystalline polymer having chemical resistance as the outer layer, the effect of preventing invasion of chemicals from the outside to the inside of the package is great.

With respect to the film composed of a liquid crystalline polymer and the film composed of polyacrylonitrile, which constitute the present invention, one or both surfaces of each film can be subjected to a surface treatment. Examples of such a surface treatment method include corona discharge treatment, plasma treatment, flame treatment, sputtering treatment, solvent treatment, ultraviolet treatment, polishing treatment, infrared treatment, and ozone treatment.

In the present invention, an adhesive layer can be interposed between a film composed of a liquid crystalline polymer and a film composed of polyacrylonitrile. In the present invention,
As a method of laminating a film composed of a liquid crystalline polymer and a film composed of polyacrylonitrile, pressure bonding,
Thermocompression bonding, ultrasonic compression bonding, dry lamination using an adhesive, lamination by melt extrusion of an adhesive resin onto a film made of the liquid crystalline polymer, or after melting the liquid crystalline polymer and polyacrylonitrile, respectively, Examples of the method include lamination by co-extrusion.

The laminated film of the present invention is a laminated film using a film composed of the above-mentioned liquid crystalline polymer and a film composed of polyacrylonitrile, and a film composed of a thermoplastic resin (however, excluding the liquid crystalline polymer and polyacrylonitrile). Film is also included.

The thermoplastic resin (excluding liquid crystal polymer and polyacrylonitrile) as used herein includes, for example, polyolefin, polystyrene, polycarbonate, polyester, polyacetal, polyamide, polyphenylene ether, polyether sulfone, ethylene-vinyl acetate Copolymers, polyvinyl chloride, polyvinylidene chloride, polyphenylene sulfide, fluororesins, acrylic resins, and the like are included. Among them, polyolefin is preferred.

As a method for producing the layer made of the thermoplastic resin, for example, the thermoplastic resin is previously formed into a film by a method such as melting and extruding from a T-die or a cylindrical die. A laminated film can also be obtained by thermocompression bonding with a liquid crystalline polymer layer or by bonding using an adhesive or an adhesive resin. A laminated film can also be obtained by melting and extruding the thermoplastic resin from the T-die or cylindrical die onto the liquid crystal polymer layer. Further, the liquid crystalline polymer and the thermoplastic resin are co-extruded to obtain a laminated film of the two first, and then pressure-bonded to the polyacrylonitrile film, thermocompression bonding, using an adhesive or an adhesive resin or the like. A laminated film can also be obtained by bonding. The thickness of the layer made of the thermoplastic resin is not particularly limited, but is preferably in the range of 1 to 1000 μm.

As another form of the laminated film of the present invention, for example, a film made of polyacrylonitrile is I, a liquid crystal polymer layer is II, and a thermoplastic resin layer (excluding liquid crystal polymer and polyacrylonitrile) is III. (III ′ and III ″ each represent a different thermoplastic resin), for example, I / II / III, I / II / III / III ′, I /
Various forms such as III / II, I / III / II / III ′ can be adopted.

Either one or both surfaces of each film constituting the present invention can be subjected to a surface treatment. Examples of such a surface treatment method include corona discharge treatment, plasma treatment, flame treatment, sputtering treatment, solvent treatment, ultraviolet treatment, polishing treatment, infrared treatment, and ozone treatment.

Further, the present invention relates to the above [1] or [2]
The present invention relates to a container using the laminated film described in (1). The container of the present invention is a container formed by using the laminated film according to the above [1] or [2], and a container made of the laminated film of the present invention, a laminated film of the present invention and still another film. And the like. The container of the present invention is suitably used as a container for various foods, beverages, detergents, pharmaceuticals, cosmetics, and the like. The container is specifically used as a bag, a pouch, a lid, a bag-in-drum container, a cataplasm package, or the like.

[0087]

EXAMPLES The present invention will be described below with reference to examples, but these are merely examples, and the present invention is not limited to these examples. (1) Liquid crystal polyester of component (A) (i) 8.3 kg (60 mol) of p-acetoxybenzoic acid, 2.49 kg (15 mol) of terephthalic acid, 0.83 kg (5 mol) of isophthalic acid and 4,4 ′ 5.45 kg (20.2 mol) of diacetoxydiphenyl was charged into a polymerization tank having a comb-shaped stirring blade, and the temperature was increased while stirring under a nitrogen gas atmosphere to carry out polymerization at 330 ° C. for 1 hour. During this time, polymerization was carried out under strong stirring while liquefying and collecting and removing acetic acid gas produced as a by-product in a cooling tube. Thereafter, the system was gradually cooled, and the polymer obtained at 200 ° C. was taken out of the system.
The obtained polymer was pulverized with a hammer mill manufactured by Hosokawa Micron Co., Ltd. to obtain particles of 2.5 mm or less. This is further heated at 280 ° C. in a rotary kiln under a nitrogen gas atmosphere.
For 3 hours to obtain a particulate wholly aromatic polyester having a flow temperature of 324 ° C. and comprising the following repeating structural units.

Here, the flow temperature is defined as the flow rate of a resin heated at a rate of 4 ° C./min using a Koka type flow tester CFT-500 manufactured by Shimadzu Corporation under a load of 100 kgf / cm ^2.
Means a temperature at which the melt viscosity shows 48000 poise when extruded from a nozzle having an inner diameter of 1 mm and a length of 10 mm.

Hereinafter, the liquid crystal polyester is abbreviated as A-1. This polymer showed optical anisotropy at 340 ° C. or more under pressure. The repeating structural units of the liquid crystal polyester A-1 are as follows.

[0090]

(2) Component (B) (i) According to the method described in Example 5 of JP-A-61-127709, methyl acrylate / ethylene / glycidyl methacrylate = 59.0 / 38.7 / 2.3
(Weight ratio), Mooney viscosity = 15, heat of fusion of crystal <1
A rubber of J / g was obtained. Hereinafter, the rubber may be abbreviated as B-1. Here, the Mooney viscosity is JIS K630.
It is a value measured using a large rotor at 100 ° C. according to 0. The heat of fusion of the crystal is determined by using DSC,
The temperature of the sample was increased from -150 ° C to 100 ° C at a rate of 20 ° C / minute, and the value was determined.

(3) Physical property measurement method (i) Gas permeability: The obtained film was measured in the following manner. Oxygen gas permeability: JIS K7126 A method (differential pressure method)
Was measured at a temperature of 20 ° C. using oxygen gas. The unit is cc / m ² · 24 hr · 1 atm. Water vapor transmission rate: Measured under the conditions of a temperature of 40 ° C. and a relative humidity of 90% according to JIS Z0208 (cup method). The unit is g / m ² · 24 hr · 1 atm.

Example 1 80% by weight of A-1 and 20% by weight of B-1 were melt kneaded using a TEX-30 type twin screw extruder manufactured by Nippon Steel Co., Ltd. at a cylinder set temperature of 350 ° C. and a screw rotation speed of 200 rpm. Was performed to obtain a composition. The pellets of this composition were supplied to a 60 mmφ single screw extruder equipped with a cylindrical die,
Melt kneading at a cylinder setting temperature of 350 ° C. and a rotation speed of 60 rpm, extruding the molten resin upward from a cylindrical die having a diameter of 50 mm, a lip interval of 1.0 mm, and a die setting temperature of 355 ° C., and drying into the hollow portion of the cylindrical film The tubular film was expanded by injecting air, and then cooled and then passed through a nip roll at a take-up speed of 55 m / min to obtain a liquid crystal polyester resin composition film. At this time, the stretching ratio in the film MD direction was 19.5, and the blow ratio was 3.
2. The film thickness was 16 μm. Hereinafter, the film may be abbreviated as G-1. First, using a table coater, about 5 g / m ^{2 of a} two-component reactive adhesive AD-503 manufactured by Toyo Morton Co., Ltd. is applied to one surface of a polyacrylonitrile film manufactured by Tamapoly Co., Ltd., Hytron BX, and a film having a thickness of 20 μm. After that, it was bonded to G-1. The oxygen permeability of the obtained laminated film is 0.7 cc / m ² · 24 h.
r · 1atm, water vapor permeability is 0.6g / m ² · 24h
r · 1 atm. The form of the laminated film is as shown in FIG. 1, and a bag of the laminated film can be obtained by thermocompression bonding using a polyacrylonitrile film and Hytron BX as a heat sealing layer. Further, as shown in FIG. 2, the polyacrylonitrile film / adhesive layer /
A laminated film composed of a film composed of a liquid crystal polymer / an adhesive layer / a polyethylene terephthalate film is also possible, and a bag having a polyacrylonitrile film as a heat sealing layer can be obtained.

[0094]

Industrial Applicability According to the present invention, it is possible to obtain a laminated film having excellent gas barrier properties, deodorant properties, heat resistance, easy post-processing after use, and leaving no ash content even when burned, and various foods.
It can be widely applied to industry as a laminated film for packaging beverages, detergents, pharmaceuticals, cosmetics and the like.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment of a laminated film of the present invention.

FIG. 2 is a cross-sectional view of one embodiment of the laminated film of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Polyacrylonitrile film 2 ... Adhesive layer 3 ... Liquid crystalline polymer film 4 ... Adhesive layer 5 ... Polyethylene terephthalate film

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F100 AK01A AK01C AK24A AK27B AK41A AK42 AK53A AL01A AL05A AN02A AS00A BA02 BA03 BA07 CB00 DA01 GB16 JB16A JB16C JC00 JD02 JJ03 JL00 4J002 CD172 CD01 CD192 CF192

Claims (9)

[Claims] 1. A laminated film comprising a film composed of a liquid crystalline polymer exhibiting optical anisotropy when melted and a film composed of polyacrylonitrile as constituents. 2. A film comprising a liquid crystalline polymer exhibiting optical anisotropy when melted, a film composed of polyacrylonitrile, and a film composed of a thermoplastic resin (excluding liquid crystal polymer and polyacrylonitrile). A laminated film characterized by the following. 3. The laminated film according to claim 1, wherein a film composed of a liquid crystalline polymer and a layer composed of polyacrylonitrile are laminated via an adhesive layer. 4. A liquid crystalline polymer which exhibits optical anisotropy when melted comprises (A) a liquid crystalline polyester as a continuous phase, and (B) a copolymer having a functional group reactive with the liquid crystalline polyester as a dispersed phase. The laminated film according to any one of claims 1 to 3, which is a liquid crystal polyester resin composition. 5. A liquid crystalline polymer exhibiting optical anisotropy when melted comprises (A) 56.0 to 99.9% by weight of a liquid crystalline polyester and (B) a copolymer having a functional group reactive with the liquid crystalline polyester. 2. A composition obtained by melt-kneading 44.0 to 0.1% by weight of a polymer.
5. The laminated film according to any one of items 1 to 4. 6. The copolymer (B) having a functional group reactive with the liquid crystal polyester, wherein the copolymer (B) contains 0.1 to 30% by weight of an unsaturated glycidyl carboxylate unit and / or an unsaturated glycidyl ether unit. The laminated film according to claim 4, wherein the laminated film is a polymer. 7. The laminated film according to claim 4, wherein the copolymer (B) having a functional group reactive with the liquid crystal polyester is a rubber having an epoxy group. 8. The laminated film according to claim 4, wherein the copolymer (B) having a functional group reactive with the liquid crystal polyester is a thermoplastic resin having an epoxy group. 9. A container using the laminated film according to claim 1.