JP2016088983A - Resin composition, heat seal agent containing the same and heat seal film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition having heat seal performance and no sorption property of a flavor component, a heat seal agent containing the resin composition and a heat seal film having a thermal fusion layer containing the heat seal agent as an innermost layer.SOLUTION: There is provided a resin composition by blending a specific small amount of an ethylene-α-olefin copolymer (B) with an ethylene-vinyl ester copolymer saponified product having a structural unit represented by the formula (1) with a content weight ratio of (A)/(B)=98/2 to 92/8. (1), where Rto Rare each independently H or an organic group, X is a single bond or a binding chain, and Rto Rare each independently H or an organic group.SELECTED DRAWING: None

Description

  The present invention relates to a resin composition containing a saponified ethylene-vinyl ester copolymer (hereinafter sometimes referred to as “EVOH resin”) as a main component, and more specifically, a resin composition suitable as a heat sealant. And a heat seal film having a heat-sealing layer containing such a heat seal agent as an innermost layer.

EVOH resin is excellent in transparency, gas barrier property, fragrance retention, solvent resistance, oil resistance, heat fusion property, etc., and taking advantage of such properties, food packaging materials, industrial chemical packaging materials, agricultural chemical packaging materials, Used as pharmaceutical packaging materials.
Of the above-mentioned various characteristics of EVOH resin, in particular, the use of fragrance retention, in other words, the non-sorption and heat-fusibility of fragrance components, packaging of food, beverages, luxury products, pharmaceuticals, cosmetics, fragrances, toiletry products, etc. In the bag, a bag having a resin layer containing EVOH resin as an innermost layer as a heat fusion layer is widely adopted.

  For example, a heat seal film having an EVOH resin having a specific equilibrium moisture content as a heat fusion layer has been proposed (see, for example, Patent Document 1).

However, since EVOH resin has a relatively high melting point, if the EVOH resin layer is used as a heat fusion layer as in Patent Document 1, it must be heat-sealed at a relatively high temperature, and layers other than the heat fusion layer are also included. The problem of softening and poor appearance after heat sealing occurred.
Therefore, there is a need for EVOH resins that can be heat sealed at relatively low temperatures.

  On the other hand, an EVOH resin having a structural unit represented by the general formula (1) having a lower melting point than that of a general EVOH resin has been developed (for example, see Patent Document 2).

  However, the heat seal film using the EVOH resin having the structural unit represented by the general formula (1) as the innermost layer (that is, the heat fusion layer) has room for improvement in terms of heat seal strength. Met.

  Furthermore, a resin composition containing an EVOH resin having a structural unit represented by the general formula (1) and an acid-modified polyolefin and a multilayer structure using the same have been proposed (for example, see Patent Document 3).

This technique relates to a resin composition having excellent impact resistance and excellent transparency and gas barrier properties even after receiving an impact, and a multilayer structure using the same.
In Patent Document 3, the content ratio of the EVOH resin having the structural unit represented by the general formula (1) and the acid-modified polyolefin (EVOH resin having the structural unit represented by the general formula (1) / acid-modified polyolefin) Is disclosed in a wide range of 99.5 / 0.5 to 50/50, but in the examples, specifically, EVOH resin / acid-modified polyolefin having a structural unit represented by the general formula (1) = 80/20 is disclosed.
That is, Patent Document 3 discloses an EVOH resin composition containing a relatively large amount of an acid-modified ethylene-α-olefin copolymer for the purpose of improving the impact resistance of a gas barrier layer as an intermediate layer. It has only been done.

JP2012-41076 JP 2004-359965 A JP 2006-96816 A

  The present invention has been made in view of the above-described points, and has a heat sealing performance and does not have aroma component sorption, a heat sealing agent containing the resin composition, and the heat sealing. The object is to provide a heat seal film having a heat-sealing layer containing an agent in the innermost layer.

［式中、Ｒ¹、Ｒ²及びＲ³はそれぞれ独立して水素原子または有機基を示し、Ｘは単結合または結合鎖を示し、Ｒ⁴、Ｒ⁵、及びＲ⁶はそれぞれ独立して水素原子または有機基を示す。］ As a result of intensive studies in view of the above circumstances, the present inventor uses a resin composition obtained by blending an EVOH resin having a structural unit represented by the general formula (1) with a specific small amount of an ethylene-α-olefin copolymer. Thus, the present inventors have found that the heat seal strength can be improved and completed the present invention.

[Wherein R ¹ , R ² and R ³ each independently represents a hydrogen atom or an organic group, X represents a single bond or a bond chain, and R ⁴ , R ⁵ and R ⁶ each independently represent hydrogen. Indicates an atom or an organic group. ]

  The EVOH resin composition of the present invention includes a resin composition having heat sealing performance and no odor component sorption, a heat sealing agent containing the resin composition, and a heat-sealing layer containing the heat sealing agent Can be used as a heat seal film having an innermost layer.

  Hereinafter, although it demonstrates in detail about the structure of this invention, these show an example of a desirable embodiment and are not specified by these content.

［式中、Ｒ¹、Ｒ²及びＲ³はそれぞれ独立して水素原子または有機基を示し、Ｘは単結合または結合鎖を示し、Ｒ⁴、Ｒ⁵、及びＲ⁶はそれぞれ独立して水素原子または有機基を示す。］ The present invention is a resin composition containing an EVOH resin (A) containing the following structural unit (1) and an ethylene-α-olefin copolymer (B), the EVOH resin (A) and ethylene-α -It is related with the resin composition characterized by the content weight ratio of an olefin copolymer (B) being a specific quantity ratio.

[Wherein R ¹ , R ² and R ³ each independently represents a hydrogen atom or an organic group, X represents a single bond or a bond chain, and R ⁴ , R ⁵ and R ⁶ each independently represent hydrogen. Indicates an atom or an organic group. ]

［式中、Ｒ¹、Ｒ²及びＲ³はそれぞれ独立して水素原子または有機基を示し、Ｘは単結合または結合鎖を示し、Ｒ⁴、Ｒ⁵、及びＲ⁶はそれぞれ独立して水素原子または有機基を示す。］ <EVOH resin>
First, the EVOH resin (A) used in the present invention is an EVOH resin containing a side chain 1,2-diol structural unit represented by the following formula (1).

[Wherein R ¹ , R ² and R ³ each independently represents a hydrogen atom or an organic group, X represents a single bond or a bond chain, and R ⁴ , R ⁵ and R ⁶ each independently represent hydrogen. Indicates an atom or an organic group. ]

In the formula (1), R ^{1 to} R ³ and R ^{4 to} R ⁶ each independently represent a hydrogen atom or an organic group. Examples of the organic group include saturated hydrocarbon groups such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group and tert-butyl group, and aromatic carbonization such as phenyl group and benzyl group. Examples thereof include a hydrogen group, a halogen atom, a hydroxyl group, an acyloxy group, an alkoxycarbonyl group, a carboxyl group, and a sulfonic acid group. Of these, a saturated hydrocarbon group having 1 to 30 carbon atoms (more preferably 1 to 15 carbon atoms, particularly preferably 1 to 4 carbon atoms) or a hydrogen atom is preferable, and a hydrogen atom is most preferable. In particular, in order to obtain excellent gas barrier performance, it is preferable that all of R ^{1 to} R ³ and R ^{4 to} R ⁶ are hydrogen atoms.

In the formula (1), X is a single bond or a bond chain. In particular, a single bond is preferable from the viewpoint of gas barrier properties of the EVOH resin.
When X is a bond chain, for example, a hydrocarbon chain such as alkylene, alkenylene, alkynylene, phenylene, naphthylene, etc. (these hydrocarbons may be substituted with halogen such as fluorine, chlorine, bromine, etc.) _{other, -O -, - (CH 2} O) m -, - (OCH 2) m -, - - (CH 2 O) nCH 2 structural units containing an ether binding site such as; -CO -, - COCO-, A structural unit containing a carbonyl group such as —CO (CH ₂ ) _m CO— or —CO (C ₆ H ₄ ) CO—; a sulfur atom such as —S—, —CS—, —SO— or —SO ₂ —; A structural unit containing a nitrogen atom such as —NR—, —CONR—, —NRCO—, —CSNR—, —NRCS—, —NRNR—, etc .; a heterostructure such as a structure containing a phosphorus atom such as —HPO ₄ — structural units containing atoms; -Si (OR) ₂ -, _{OSi (OR) 2 -, -} OSi (OR) a structural unit containing ₂ O- such as silicon _{atoms; -Ti (OR) 2 -,} - OTi (OR) 2 -, - OTi (OR) 2 O- , etc. Structural units containing a titanium atom; structural units containing a metal atom such as an aluminum atom such as -Al (OR)-, -OAl (OR)-, and -OAl (OR) O-. In these structural units, each R is independently an arbitrary substituent, and is preferably a hydrogen atom or an alkyl group. M is a natural number, and is usually 1-30, preferably 1-15, particularly preferably 1-10. Among these, from the viewpoint of stability during production or use, a hydrocarbon chain having 1 to 10 carbon atoms is preferable, and a hydrocarbon chain having 1 to 6 carbon atoms, particularly a hydrocarbon chain having 1 carbon atom is preferable. .

The most preferable structure in the side chain 1,2-diol structural unit represented by the above formula (1) is a structural unit in which all of R ^{1 to} R ⁶ are hydrogen atoms and X is a single bond. That is, the structural unit represented by the following formula (1a) is most preferable.

The content of the side chain 1,2-diol structural unit in the side chain 1,2-diol structural unit-containing EVOH resin is usually 0.1 to 15 mol%, preferably 1 to 10 mol%, Most preferably, it is 2-5 mol%. When there is too little content of a side chain 1, 2-diol structural unit, there exists a tendency for the transparency of a sealing agent part to fall. On the other hand, when there is too much content of a side chain 1, 2-diol structural unit, there exists a tendency for gas barrier property to fall.
The content of the side chain 1,2-diol structural unit can be calculated from the measurement result of ¹ H-NMR.

  The ethylene content in the side chain 1,2-diol structural unit-containing EVOH-based resin is the content of ethylene structural units measured based on ISO 14663, and is usually 20 to 60 mol%, preferably 25 to 50 mol%, More preferably, it is 30-45 mol%. When the content of the ethylene structural unit is too low, the hygroscopicity is increased, so that the gas barrier property under a high humidity condition is lowered or the adhesiveness to the glass substrate is lowered. On the other hand, if the content of the ethylene structural unit is too high, the proportion of OH groups contained in the polymer chain inevitably decreases and the gas barrier property tends to decrease.

  The degree of saponification of the EVOH resin containing a side chain 1,2-diol structural unit is a value measured based on JIS K6726, and is usually 90 mol% or more, preferably 98 mol%, particularly preferably 99.5. More than mol%. If the degree of saponification is too low, gas barrier properties tend to be insufficient.

  The melting point of the side chain 1,2-diol structural unit-containing EVOH-based resin having the above-described configuration is usually 100 to 220 ° C., preferably 130 to 200 ° C. as measured by a differential scanning calorimeter. Especially preferably, it is 140-190 degreeC.

  The melt flow rate (sometimes abbreviated as MFR) of the EVOH resin containing a side chain 1,2-diol structural unit is usually 1 to 100 g / 10 min at 210 ° C. and a load of 2160 g, preferably 1 to 50 g / 10. Min, particularly preferably 2 to 20 g / 10 min. When the MFR is too small, the viscosity is high, and when the resulting EVOH resin layer film or sheet is molded, the inside of the extruder tends to be in a high torque state and the melt moldability tends to decrease. Is low, and the thickness accuracy tends to decrease during molding of the EVOH resin layer film or sheet.

  Such an EVOH resin is a water-insoluble resin, and is obtained by saponifying a copolymer of ethylene, a vinyl ester monomer, and a comonomer that is a raw material of a 1,2-diol structural unit in the side chain. It is obtained by saponifying an ethylene-vinyl ester copolymer. The ethylene-vinyl ester copolymer is produced by any known polymerization method, for example, solution polymerization, suspension polymerization, emulsion polymerization, etc., and the ethylene-vinyl ester copolymer is saponified by a known method. obtain.

  The vinyl ester monomer is typically vinyl acetate from the viewpoint of market availability and good impurity treatment efficiency during production. In addition, for example, vinyl formate, vinyl acetate, vinyl propionate, vinyl valelate, vinyl butyrate, vinyl isobutyrate, vinyl pivalate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl versatate, etc. Aliphatic vinyl esters, aromatic vinyl esters such as vinyl benzoate, and the like, and are usually aliphatic vinyl esters having 3 to 20 carbon atoms, preferably 4 to 10 carbon atoms, and particularly preferably 4 to 7 carbon atoms. is there. These are usually used alone, but a plurality of them may be used simultaneously as necessary.

  As the comonomer capable of supplying the side chain 1,2-diol unit, when an EVOH resin containing the structural unit (1a) which is the most preferable structure is taken as an example, 3,4-diol-1-butene, 3,4- Diol derivatives such as diacyloxy-1-butene, 3-acyloxy-4-ol-1-butene, 4-acyloxy-3-ol-1-butene, carbonate compounds such as vinylethylene carbonate, 2,2-dialkyl-4- Examples include acetal compounds such as vinyl-1,3-dioxolane.

  Among these, a diol derivative is preferably used from the viewpoint of reactivity with the vinyl ester monomer and a point that a by-product resulting from saponification is in common with the vinyl ester monomer.

  Furthermore, it may contain a copolymerizable monomer within a range that does not impair the properties of the EVOH resin (for example, 5 mol% or less with respect to the EVOH resin). For example, specifically, olefins such as propylene, 1-butene and isobutene, unsaturated acids such as acrylic acid, methacrylic acid, crotonic acid, (anhydrous) phthalic acid, (anhydrous) maleic acid and (anhydrous) itaconic acid, or Salts thereof, mono- or dialkyl esters having 1 to 18 carbon atoms, acrylamide, N-alkyl acrylamides having 1 to 18 carbon atoms, N, N-dimethylacrylamide, 2-acrylamidopropanesulfonic acid or salts thereof, acrylamidopropyldimethylamine or Acrylates such as acid salts or quaternary salts thereof, methacrylamide, N-alkylmethacrylamide having 1 to 18 carbon atoms, N, N-dimethylmethacrylamide, 2-methacrylamide propanesulfonic acid or salts thereof, methacrylamidepropyl Zimechi Methacrylamides such as amines or acid salts thereof or quaternary salts thereof, N-vinylamides such as N-vinylpyrrolidone, N-vinylformamide and N-vinylacetamide, vinyl cyanides such as acrylonitrile and methacrylonitrile, carbon Number 1 to 18 alkyl vinyl ethers, hydroxyalkyl vinyl ethers, vinyl ethers such as alkoxyalkyl vinyl ethers, vinyl chloride, vinylidene chloride, vinyl halides such as vinyl fluoride, vinylidene fluoride, vinyl bromide, trimethoxyvinyl silane, etc. Allyl halide compounds such as vinylsilanes, allyl acetate and allyl chloride, allyl alcohols such as allyl alcohol and dimethoxyallyl alcohol, trimethyl- (3-acrylamido-3-dimethylpropyl) -a Examples include ammonium chloride and acrylamido-2-methylpropanesulfonic acid. These monomers may be used alone or in combination of two or more.

  The side chain 1,2-diol structural unit-containing EVOH resin is not only one type, but also has different saponification degrees, different molecular weights, different types of copolymerization monomers, ethylene structure Two or more kinds of side chain 1,2-diol structural unit-containing EVOH resins such as those having different unit contents may be used in combination.

  In some cases, an unmodified EVOH resin not containing a side chain 1,2-diol structural unit may be mixed. In the case of an EVOH-based resin mixture, the content of the side chain 1,2-diol structural unit is usually 0.5 to 30 mol%, preferably 1 to 20 mol%, as an average value of the entire EVOH-based resin mixture. In particular, it is preferable to mix at a ratio of 1 to 10 mol%.

  When two or more different EVOH-based resins containing side chain 1,2-diol structural units are used by blending, the method for producing the blend is not particularly limited. For example, a method in which each paste of vinyl ester copolymer before saponification is mixed and then saponified; a method in which an EVOH resin after saponification is dissolved in alcohol or a mixed solvent of water and alcohol; and a method in which each EVOH is mixed Examples thereof include a method of mixing and kneading the resin-based resin pellets or powder.

  Furthermore, in order to improve various physical properties such as thermal stability of EVOH resin, organic acids such as acetic acid, propionic acid, butyric acid, lauric acid, stearic acid, oleic acid, behenic acid, or alkali metal salts thereof (sodium, Potassium), alkaline earth metal salts (calcium, magnesium, etc.), inorganic acids such as sulfuric acid, sulfurous acid, carbonic acid, phosphoric acid, boric acid, or alkali metal salts thereof (sodium, potassium, etc.), Additives such as salts such as alkaline earth metal salts (calcium, magnesium, etc.) may be added. Of these, it is particularly preferable to add boron compounds, acetates and phosphates including acetic acid, boric acid and salts thereof.

  When acetic acid is added, the amount added is usually 0.001 to 1 part by weight, preferably 0.005 to 0.2 part by weight, and particularly preferably 0.010 to 0.0. 1 part by weight. If the amount of acetic acid added is too small, the effect of acetic acid content tends not to be obtained sufficiently, and conversely if too large, it tends to be difficult to obtain a uniform film or sheet.

  Moreover, when adding a boron compound, the addition amount is usually 0.001 to 1 part by weight in terms of boron (analyzed by ICP emission analysis after ashing) with respect to 100 parts by weight of the EVOH resin. Preferably it is 0.002-0.2 weight part, Most preferably, it is 0.005-0.1 weight part. If the addition amount of the boron compound is too small, the effect of adding the boron compound may not be sufficiently obtained. Conversely, if the addition amount is too large, it tends to be difficult to obtain a uniform film or sheet.

  Further, the amount of acetate and phosphate (including hydrogen phosphate) added is usually 0. 100 parts by weight of EVOH resin in terms of metal (after ashing and analyzed by ICP emission analysis). 0005 to 0.1 parts by weight, preferably 0.001 to 0.05 parts by weight, particularly preferably 0.002 to 0.03 parts by weight. If the amount added is too small, the effect of inclusion is sufficiently obtained. On the contrary, if it is too much, it tends to be difficult to obtain a uniform film or sheet. In addition, when adding 2 or more types of salts to EVOH-type resin, it is preferable that the sum total exists in the range of said addition amount.

Other additives include, for example, saturated aliphatic amides (for example, stearic acid amide), unsaturated fatty acid amides (for example, oleic acid amide), bis fatty acid amides (for example, ethylene bisstearic acid amide), low Lubricants such as molecular weight polyolefin (for example, low molecular weight polyethylene having a molecular weight of about 500 to 10,000, or low molecular weight polypropylene), insoluble inorganic salts (for example, hydrotalcite), aliphatic such as ethylene glycol, glycerin, hexanediol Plasticizers such as polyhydric alcohols, light stabilizers, antioxidants, UV absorbers, colorants, antistatic agents, surfactants, antibacterial agents, antiblocking agents, fillers (for example, inorganic fillers), oxygen absorption Agents (for example, ring-opening polymers of cycloalkenes such as polyoctenylene and conjugated dimers such as butadiene) Cyclized down polymer, etc.), conjugated polyene compounds (e.g., sorbic acid, sorbic acid esters, sorbate and the like) and the like.
These compounding agents other than EVOH-based resins are usually less than 30% by weight, preferably less than 20% by weight, and particularly preferably less than 10% by weight.

<Ethylene-α-olefin copolymer (B)>
Next, the ethylene-α-olefin copolymer (B) used in the present invention is not particularly limited. For example, ethylene and 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, A copolymer with an α-olefin having 1 to 8 carbon atoms such as 1-octene can be exemplified.
Among these, an ethylene-α-olefin copolymer using an α-olefin having 4 to 8 carbon atoms is preferably used.

  Although it does not specifically limit as molecular weight of an ethylene-alpha-olefin copolymer (B), Usually, it is 100-10 million, Preferably it is 1000-5 million, Most preferably, it is 10000-3000000.

  The copolymerization ratio of the ethylene-α-olefin copolymer (B) is not particularly limited, but the content of α-olefin is usually 1 to 80 wt%, preferably 5 to 70 wt%, particularly preferably 10 to 60 wt%. %.

  The ethylene-α-olefin copolymer (B) in the resin composition of the present invention may be a modified product.

  Examples of such modified products include acid-modified products, post-modified products such as urethanization and acetalization, and copolymerization-modified products with other monomers. EVOH having a structural unit represented by the general formula (1) From the viewpoint of dispersibility in the resin (A), an acid-modified product is preferable.

  The acid-modified ethylene-α-olefin copolymer is not particularly limited, and examples thereof include ethylene-propylene copolymer (EPR), ethylene-butene copolymer rubber (EBR), and ethylene-octene copolymer rubber (EOR). ) And the like are modified with an acid such as an unsaturated carboxylic acid or an anhydride thereof. Specifically, the unsaturated carboxylic acid or an anhydride thereof is added to an ethylene-α-olefin copolymer rubber, a graft reaction or the like. And a modified ethylene-α-olefin copolymer containing a carboxyl group obtained by chemical bonding. In particular, an acid graft-modified ethylene-α-olefin copolymer is preferable, and a maleic anhydride graft-modified ethylene-α-olefin copolymer is more specifically mentioned.

  The modification amount of the modified ethylene-α-olefin copolymer is not particularly limited, but is usually 0.001 to 30 wt%, preferably 0.01 to 20 wt%, particularly preferably 0.1 to 10 wt%.

  From the viewpoint of suppressing the reaction with the EVOH resin (A) having the structural unit represented by the general formula (1) as the ethylene-α-olefin copolymer, acid-modified ethylene-α-olefin copolymer and unmodified ethylene It is preferable to mix a -α-olefin copolymer.

  When the acid-modified ethylene-α-olefin copolymer and the unmodified ethylene-α-olefin copolymer are mixed, the acid-modified ethylene-α-olefin copolymer and the unmodified ethylene-α-olefin copolymer are contained. The quantitative ratio (acid-modified ethylene-α-olefin copolymer / unmodified ethylene-α-olefin copolymer) is usually 90/10 to 40/60, preferably 85/15 to 50/50, more preferably 80. / 20 to 60/40. When the weight ratio is large, the dispersibility of the unmodified ethylene-α-olefin copolymer in the EVOH resin tends to be reduced and tends to aggregate. On the other hand, when the weight ratio is small, the EVOH resin and the acid-modified ethylene-α-olefin are apt to aggregate. The reaction with the copolymer generates bumps and tends to lead to poor appearance.

<Resin composition>
The resin composition of the present invention comprises an EVOH resin (A) having a structural unit represented by the general formula (1) and an ethylene-α-olefin copolymer (B), and the content weight ratio thereof. (A / B) is 98/2 to 92/8, preferably 97/3 to 93/7, and more preferably 96/4 to 94/6. When such a weight ratio is large, the heat seal strength tends to decrease, whereas when it is small, the fragrance retention property tends to decrease.

  The method for blending the EVOH resin (A) having the structural unit represented by the general formula (1) and the ethylene-α-olefin copolymer (B) for obtaining the resin composition of the present invention is not particularly limited. A melt mixing method is preferable in that uniform mixing is possible.

  As the method of melt mixing, for example, a known kneading apparatus such as a kneader rudder, an extruder, a mixing roll, a Banbury mixer, a plast mill, etc. can be used. Usually, a single or twin screw extruder is used. It is industrially preferable to use it, and it is also preferable to provide a vent suction device, a gear pump device, a screen device, etc. as needed. In particular, in order to remove moisture and by-products (such as pyrolytic low molecular weight substances), one or more vent holes are provided in the extruder and suction is performed under reduced pressure, or oxygen is prevented from entering the extruder. Therefore, by continuously supplying an inert gas such as nitrogen into the hopper, a resin composition having excellent quality with reduced thermal coloring and thermal deterioration can be obtained.

  Also, the method of supplying each resin to the extruder is not particularly limited. B) A method of dry blending the EVOH resin and the acid-modified polyolefin resin and supplying them to the extruder all at once. B) EVOH resin or acid-modified A method in which one of the polyolefin resins is supplied to an extruder and melted to supply the other solid (solid side feed method), c) EVOH resin or one of acid-modified polyolefin resins is extruded The method of supplying the other of the molten state to the machine where it is melted by supplying to the machine (melt side feed method) can be mentioned, among others, the method of a) is the simplicity of the apparatus, the cost of the blend, etc. And industrially practical.

[Other additives]
The resin composition of the present invention thus obtained can be used for melt molding or the like as it is, but in the present invention, a saturated aliphatic amide (for example, as long as the object of the present invention is not hindered by the resin composition) Stearic acid amide), unsaturated fatty acid amide (such as oleic acid amide), bis fatty acid amide (such as ethylene bis stearic acid amide), fatty acid metal salt (such as calcium stearate, magnesium stearate), low molecular weight polyolefin (such as Lubricants such as low molecular weight polyethylene having a molecular weight of about 5 0 to 10 0, 0 0 or low molecular weight polypropylene, etc. (excluding (B)), inorganic salts (for example, hydrotalcite), plasticizers (for example, ethylene glycol) , Aliphatic polyhydric alcohols such as glycerin and hexanediol), oxygen absorption (For example, reduced iron powders as inorganic oxygen absorbents, water-absorbing substances and electrolytes added thereto, aluminum powder, potassium sulfite, photocatalytic titanium oxide, etc., ascorbic acid as organic compound oxygen absorbents In addition, fatty acid esters and metal salts thereof, hydroquinone, gallic acid, polyhydric phenols such as hydroxyl group-containing phenol aldehyde resin, bis-salicylaldehyde-imine cobalt, tetraethylenepentamine cobalt, cobalt-Schiff base complex, porphyrins, Polymers such as macrocyclic polyamine complexes, polyethyleneimine-cobalt complexes such as coordination compounds of nitrogen-containing compounds and transition metals, terpene compounds, reactants of amino acids and reducing substances containing hydroxyl groups, triphenylmethyl compounds, etc. Nitrogen-containing resin and transition as an oxygen absorber Coordination conjugate with genus (eg, M X D nylon and cobalt combination), tertiary hydrogen-containing resin and transition metal blend (eg, polypropylene and cobalt combination), carbon-carbon unsaturated bond-containing resin And transition metal blends (eg, a combination of polybutadiene and cobalt), photo-oxidatively disintegrating resins (eg: polyketones), anthraquinone polymers (eg: polyvinylanthraquinone), etc. Benzophenone, etc.), peroxide supplements (commercially available antioxidants, etc.) and deodorants (activated carbon, etc.)), heat stabilizers, light stabilizers, antioxidants, UV absorbers, colorants , Antistatic agents, surfactants, antibacterial agents, antiblocking agents, slip agents, fillers (for example, inorganic fillers), other resins (for example, polyamides), etc. It may be.

  Furthermore, boron can be added to the resin composition of the present invention by adding acids such as acetic acid and phosphoric acid or metal salts thereof such as alkali metals, alkaline earth metals, and transition metals within the range that does not impair the object of the present invention. It is preferable to add boric acid or a metal salt thereof as a compound in terms of improving the thermal stability of the resin.

  The amount of acetic acid added was 0. It is preferable that the content is 0.01 to 1 part by weight (further, 0.05 to 0.2 part by weight, particularly 0.01 to 0 to 0.1 part by weight). If the amount is less than 0 0 1 part by weight, the content effect may not be sufficiently obtained. On the other hand, if it exceeds 1 part by weight, the resulting molded article tends to deteriorate in appearance, which is not preferable.

  In addition, borate metal salts include calcium borate, cobalt borate, zinc borate (zinc tetraborate, zinc metaborate, etc.), aluminum borate / potassium borate, ammonium borate (ammonium metaborate, ammonium tetraborate, Ammonium pentaborate, ammonium octaborate, etc.), cadmium borate (cadmium orthoborate, cadmium tetraborate, etc.), potassium borate (potassium metaborate, potassium tetraborate, potassium pentaborate, potassium hexaborate, Potassium octaborate), silver borate (silver metaborate, silver tetraborate, etc.), copper borate (cupric borate, copper metaborate, copper tetraborate, etc.), sodium borate (sodium metaborate) , Sodium diborate, sodium tetraborate, sodium pentaborate, sodium hexaborate, sodium octaborate ), Lead borate (lead metaborate, lead hexaborate, etc.), nickel borate (nickel orthoborate, nickel diborate, nickel tetraborate, nickel octaborate, etc.), barium borate (orthoboric acid) Barium, barium metaborate, barium diborate, barium tetraborate, etc.), bismuth borate, magnesium borate (magnesium orthoborate, magnesium diborate, magnesium metaborate, trimagnesium tetraborate, pentamagnesium tetraborate) Etc.), manganese borate (manganese borate, manganese metaborate, manganese tetraborate, etc.), lithium borate (lithium metaborate, lithium tetraborate, lithium pentaborate, etc.), borax, Borate minerals such as carnite, inyoite, agateite, suiyanite, zyberite, etc. It is, preferably borax, boric acid, sodium borate (sodium metaborate, sodium diborate, sodium tetraborate, sodium pentaborate, sodium hexaborate acid, eight sodium borate, etc.). Further, the boron compound was added in an amount of 0.00 in terms of boron with respect to 100 parts by weight of all EVOH resins in the composition. It is preferable that the content is 0.01 to 1 part by weight (more preferably 0.0 0.02 to 0.2 part by weight, and particularly 0.0 0.05 to 0.1 part by weight). If the amount is less than 0 0 1 part by weight, the content effect may not be sufficiently obtained. On the other hand, if it exceeds 1 part by weight, the resulting molded article tends to deteriorate in appearance, which is not preferable.

  Such metal salts include sodium, potassium, calcium, magnesium, and other organic acids such as acetic acid, propionic acid, butyric acid, lauric acid, stearic acid, oleic acid, and behenic acid, sulfuric acid, sulfurous acid, carbonic acid, and phosphoric acid. And metal salts of inorganic acids such as acetate, phosphate and hydrogen phosphate are preferred. In addition, the amount of the metal salt added is 0.00 on a metal basis with respect to 100 parts by weight of the EVOH resin in the resin composition. 0 0 0 5 to 0. It is preferably 1 part by weight (further, 0.001 to 0.05 part by weight, particularly 0.02 to 0.03 part by weight). If the amount is less than 0 0 0 5 parts by weight, the content effect may not be sufficiently obtained. If it exceeds 1 part by weight, the resulting molded article tends to deteriorate in appearance, which is not preferable. In addition, when adding 2 or more types of alkali metal and / or alkaline-earth metal salt to EVOH resin, it is preferable that the total is in the range of said addition amount.

  The method of adding acids or metal salts thereof to the resin composition is not particularly limited. A) A porous precipitate of EVOH resin having a water content of 20 to 80% by weight is mixed with an aqueous solution of acids or metal salts thereof. A method in which the acid or its metal salt is dried after contact, and a) EVOH resin in a uniform solution (water / alcohol solution, etc.) is mixed with the acid or its metal salt, and then in a strand form in the coagulation liquid A method in which the obtained strand is cut into pellets and further dried as pellets; c) a method in which EVOH resin and acids or metal salts thereof are mixed together and then melt-kneaded with an extruder or the like; ) A method in which the resin composition and acids and metal salts thereof are mixed together and then melt-kneaded with an extruder or the like. E) The alkali used in the saponification step during the production of EVOH resin (sodium hydroxide, Examples include a method in which potassium hydroxide is neutralized with an acid such as acetic acid, and the amount of remaining acid such as acetic acid and by-product sodium metal salt such as sodium acetate or potassium acetate is adjusted by washing with water. be able to. In order to obtain the effects of the present invention more remarkably, the method (a), (b) or (v), which is excellent in dispersibility of acids and metal salts thereof, is preferred.

  The EVOH resin composition obtained by the above methods a), b) or e) is dried after a salt or a metal salt is added.

  As such a drying method, various drying methods can be employed. For example, fluidized drying in which a substantially pellet-like EVOH resin is mechanically or stirred and dispersed by hot air, or a substantially pellet-like EVOH resin is subjected to dynamic actions such as stirring and dispersion. As a dryer for performing fluidized drying, a cylindrical / grooved stirred dryer, a circular tube dryer, a rotary dryer, a fluidized bed dryer, a vibrating fluidized bed dryer, Conical rotary dryers, etc., and as a dryer for performing stationary drying, as a material stationary type, a batch box dryer is used, and as a material transfer type, a band dryer, tunnel dryer, Examples thereof include, but are not limited to, a mold dryer. It is also possible to combine fluidized drying and stationary drying.

  Air or an inert gas (nitrogen gas, helium gas, argon gas, etc.) is used as the heating gas used in the drying process, and the temperature of the heating gas is 40 to 15 ° C. This is preferable in terms of preventing thermal degradation of EVOH resin. The drying treatment time is usually about 15 minutes to 72 hours, although it depends on the water content of the EVOH resin and its treatment amount, from the viewpoint of productivity and prevention of thermal deterioration of the EVOH resin.

  The EVOH resin composition is dried under the above conditions. The water content after the drying treatment is 0.01 to 5% by weight (more preferably 0.01 to 2% by weight, particularly 0. 0%). 1 to 1 part by weight), and the water content is preferably 0. If it is less than 0 0 1% by weight, the long run moldability tends to decrease. Conversely, if it exceeds 5% by weight, foaming may occur during extrusion molding.

  Such EVOH resin may contain some monomer residue (3,4-diol-1-butene, 3,4-diacyloxy-1-butene, 3-acyloxy-4-ol--to the extent that the object of the present invention is not impaired. 1-butene, 4-acyloxy-3-ol-1-butene, 4,5-diol-1-pentene, 4,5-diacyloxy-1-pentene, 4,5-diol-3-methyl-1-pentene, 4,5-diol-3-methyl-1-pentene, 5,6-diol-1-hexene, 5,6-diacyloxy-1-hexene, 4,5-diacyloxy-2-methyl-1-butene and the like Monomer saponification product (3,4-diol-1-butene, 4,5-diol-1-pentene, 4,5-dio Le - 3 - methyl - 1 - pentene, 4, 5 - diol - 3 - methyl - 1 - pentene, 5, 6 - diol - 1 - hexene) may be contained.

<Heat sealant>
The resin composition of the present invention can be used as a heat sealing agent when used as a heat-sealing layer.

<Heat seal film>
The resin composition of the present invention can be used as a heat seal film having a heat-sealing layer containing the resin composition as an innermost layer.
Moreover, in obtaining this heat-sealing film, a well-known method is employable.

  For example, the film can be produced by an inflation film molding machine, a T-die / cast film molding machine, an extrusion coating molding machine, a solution coating molding machine, or the like. The heat seal film may be a multilayer or a single layer as long as the heat-sealing layer is at least one innermost layer, but is usually laminated with other layers as a laminate. Often used.

In producing the laminate, it may be arranged so that the surface of the resin composition is heat-sealed, and it is usually arranged in the innermost layer of the laminate.
That is, another base material (thermoplastic resin or the like) is laminated on one side of the heat seal film, but as a lamination method, for example, a method of melt extrusion laminating another base material on the heat seal film, or the other way around A method of melt-extrusion laminating the resin composition (resin composition used for a heat seal film) on the base material, a method of co-extruding the resin composition and another base material, a heat seal film and another base material ( And a method of dry laminating the layer with a known adhesive such as an organic titanium compound, an isocyanate compound, a polyester compound, or a polyurethane compound. The melt molding temperature at the time of melt extrusion is often selected from the range of 150 to 300 ° C.

  As such other base materials, thermoplastic resins are useful. Specifically, linear low density polyethylene, low density polyethylene, ultra-low density polyethylene, medium density polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer Polymer, ionomer, ethylene-propylene (block or random) copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ethylene-methacrylic acid copolymer, ethylene-methacrylic acid ester copolymer, Polypropylene, propylene-α-olefin (α-olefin having 4 to 20 carbon atoms) copolymer, polybutene, polypentene, polymethylpentene, or other olefin homo- or copolymers, or these olefin homo- or copolymers. Graft modified with unsaturated carboxylic acid or its ester Polyolefin resin, polyester resin, polyamide resin (including copolyamide), polyvinyl chloride, polyvinylidene chloride, acrylic resin, polystyrene resin, vinyl ester resin, polyester elastomer, polyurethane elastomer, chlorine Polyethylene, chlorinated polypropylene, aromatic or aliphatic polyketones, polyalcohols obtained by reducing these, and EVOH resins, etc., and practical properties such as laminate properties (particularly strength and appearance). From the point of view, polypropylene, ethylene-propylene (block or random) copolymer, polyamide, polyethylene, ethylene-vinyl acetate copolymer, polystyrene, polyethylene terephthalate (PET), polyethylene naphthalate (PEN) are preferred. It used are, in particular, polyolefin resins, polyester resins, polyamide resins are preferable.

  Furthermore, when extruding and coating another base material on the heat seal film, or laminating a film, sheet or the like of another base material using an adhesive, the base material may be any other than the thermoplastic resin described above. A substrate (paper, metal foil, uniaxially or biaxially stretched plastic film or sheet and its inorganic deposit, woven fabric, non-woven fabric, metallic cotton, wood, etc.) can also be used.

  When the heat seal film layer is a (a1, a2,...) And another substrate, for example, a thermoplastic resin layer is b (b1, b2,...), The layer structure of the laminate is a / b / b / a, a1 / a2 / b, a / b1 / b2, a / b2 / b1 / a / b1 / b2, b2 / b1 / a / b1 / a, a1 / B1 / a2 / b2 and the like can be combined. Furthermore, when R is a regrind layer comprising at least a mixture of the resin composition and a thermoplastic resin, b / R / a, b / R / b / a, b2 / b1 / R / a1 / a2, b / R / a / R / a / R / a, and the like are also possible.

In the above layer structure, an adhesive resin layer can be provided between the respective layers as necessary, and various adhesive resins can be used, and the stretchability is excellent. It is preferable in that a laminate can be obtained, and varies depending on the type of resin b, but cannot be generally stated, but an unsaturated carboxylic acid or its anhydride is added to an olefin polymer (the above-mentioned olefin simple substance or copolymer) by addition reaction or grafting. Examples thereof include modified olefin polymers containing a carboxyl group obtained by chemical bonding by reaction or the like. Specifically, maleic anhydride graft-modified polyethylene, maleic anhydride graft-modified polypropylene, maleic anhydride graft Modified ethylene-propylene (block or random) copolymer, maleic anhydride graft modified ethylene-ethyl Acrylate copolymer, maleic anhydride graft-modified ethylene anhydride - one or a mixture of two or more species selected from vinyl acetate copolymers and the like as preferred. The amount of the unsaturated carboxylic acid or anhydride thereof contained in the thermoplastic resin at this time is preferably 0.001 to 3% by weight, more preferably 0.01 to 1% by weight, particularly preferably 0.03. ~ 0.5 wt%. If the amount of modification in the modified product is small, the adhesiveness may be insufficient. On the other hand, if the amount is too large, a crosslinking reaction may occur and the moldability may be deteriorated. These adhesive resins can be blended with the resin composition, EVOH resin, polyisobutylene, rubber / elastomer components such as ethylene-propylene rubber, and further, the resin of the b layer. In particular, blending a polyolefin resin different from the base polyolefin resin of the adhesive resin is useful because the adhesiveness may be improved.

  The thickness of each layer of the laminate cannot be generally stated depending on the layer configuration, the type of b, the application and container form, the required physical properties, etc., but usually the a layer is 1 to 200 μm (more preferably 3 to 100 μm, especially 5 to 30 μm), b layer is 2 to 400 μm (more 6 to 200 μm, especially 10 to 80 μm), and the adhesive resin layer is 1 to 200 μm (further 3 to 100 μm, especially 5 to 20 μm). Selected. If the a layer is less than 1 μm, the gas barrier properties and heat sealability are insufficient, and the thickness control becomes unstable. On the other hand, if it exceeds 200 μm, the impact resistance is inferior and not economical, and the b layer is 2 μm. Less than 400 μm, the weight increases and is not economical and not preferable. If the adhesive resin layer is less than 1 μm, the interlayer adhesion is insufficient, and the thickness control becomes unstable. On the other hand, if it exceeds 200 μm, the weight increases, and it is not economical and not preferable.

  The laminate is used for various heat sealing applications as it is, but it is also preferable to subject the laminate to a heat stretching treatment for the purpose of improving the physical properties of the laminate. Here, the heat-stretching treatment is for stretching a laminate that has been heated thermally uniformly. The stretching may be either uniaxial stretching or biaxial stretching, and stretching is performed at as high a magnification as possible. Therefore, it is possible to obtain an excellent stretched laminate that has better physical properties and does not cause pinholes, cracks, stretch unevenness, uneven thickness, delamination, or the like during stretching.

  As a stretching method, a roll stretching method, a tenter stretching method, a tubular stretching method, a stretching blow method, a vacuum forming method, a pressure forming method, a vacuum pressure forming method, or the like can be used. In the case of biaxial stretching, both a simultaneous biaxial stretching method and a sequential biaxial stretching method can be employed. The stretching temperature is selected from the range of about 60 to 170 ° C, preferably about 80 to 160 ° C.

It is also preferable to perform heat setting after the completion of stretching. The heat setting can be carried out by a known means, and the heat treatment is performed at 80 to 170 ° C., preferably 100 to 160 ° C. for about 2 to 600 seconds while keeping the stretched film in a tension state. In addition, when used for heat shrink packaging applications such as raw meat, processed meat, cheese, etc., after heat stretching after stretching, it is a product film, and after storing the above raw meat, processed meat, cheese, etc. in the film, The film is heat-shrinked at 50 to 130 ° C., preferably 70 to 120 ° C. for about 2 to 300 seconds, and the film is heat-shrinked for close-packaging.

  In addition, the obtained laminate can be subjected to heat treatment, cooling treatment, rolling treatment, printing treatment, dry lamination treatment, solution or melt coating treatment, bag making processing, deep drawing processing, box processing, tube processing, split processing, etc. It can be carried out.

As the heat sealing apparatus, a normal apparatus such as a hot plate type or an impulse type can be adopted, but the hot plate type is preferable from the viewpoint of accuracy of temperature control and shortening of the heat sealing time. The heat seal time (contact time of the hot plate) is about 0.1 to 5 seconds, the pressure is 0.1 to 5 kg / cm <2>, and the temperature is 100 to 170 [deg.] C.
Moreover, when obtaining a packaging bag, a normal bag making machine can be employed, for example, a hot seal type or hot roll type bag making machine can be used, a side seal type, a three-sided seal type, a joint seal type. It is used after being processed into bags. Moreover, automatic bag making and filling machines such as pillow packaging, three-side seal packaging, and four-side seal packaging that simultaneously fill a bag and contents can be used.

The heat seal film of the present invention has a heat seal strength of 10 N / 15 mm obtained by facing the heat-sealing layers to each other and pressure-bonding them for 1 second at a temperature of 147 ° C. and a pressure of 0.2 MPa using a hot plate heat sealer. It is good to be above.
In addition, the heat sealing | fusion layers made to face may be the same and may differ.
The heat seal film can obtain excellent heat seal strength by heat sealing, and can be suitably used as a heat seal film for packaging bags having high fragrance retention.

  Thus, a laminate in which the resin composition of the present invention is arranged as a heat seal material is obtained. Such a laminate can be used for various packaging applications (food, beverages, cosmetics, pharmaceuticals, industrial chemicals, agricultural chemicals, solvents, It is useful as a packaging material for fuel and the like, and is particularly useful as a laminate of polyolefin resin, polyester resin, and polyamide resin.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the description of the examples unless it exceeds the gist.
In the examples, “part” means a weight basis unless otherwise specified.

<Example 1>
[Production of EVOH resin (A)]
In a 1 m ³ polymerization can with cooling coil, 330 kg of vinyl acetate, 60 kg of methanol, 400 ppm of acetyl peroxide (vs. vinyl acetate), 30 ppm of citric acid (vs. vinyl acetate), and 14 kg of 3,4-diacetoxy-1-butene First, after replacing the system with nitrogen gas, and then replacing with ethylene, the pressure was increased until the ethylene pressure reached 49 kg / cm 2 and the temperature was raised to 67 ° C. with stirring, so that the polymerization rate reached 60%. Polymerization was carried out for 6 hours until completion. Thereafter, the polymerization reaction was stopped to obtain an ethylene-vinyl acetate-diacetoxybutene terpolymer having an ethylene content of 37 mol%.

  By supplying a methanol solution containing 0.008 equivalents of sodium hydroxide to the methanol solution of the ethylene-vinyl acetate-diacetoxybutene terpolymer with respect to the remaining acetate groups in the copolymer, Methanol solution of EVOH resin containing saponification and containing 1.5 mol% of the structural unit having the above-mentioned side chain 1,2-glycol bond (see formula (1a)) (EVOH resin 30%, methanol 70%) )

The obtained methanol solution of EVOH resin was extruded into cold water in a strand shape, and the obtained strand material (hydrous porous material) was cut with a cutter, and the diameter was 3.8 mm and the length was 4 mm.
An EVOH resin porous pellet having a resin content of 35% was obtained.

  The obtained porous pellets were washed with water, poured into an aqueous solution containing 0.048% boric acid and stirred at 35 ° C. for 4 hours, and then 110 ° C. in a nitrogen stream having an oxygen concentration of 0.5% or less. The EVOH resin (A1) having a volatile content of 0.17 wt% [ethylene content 37 mol%, saponification degree 99.7 mol%, side chain 1,2-diol structural unit (1a ) Content 1.5 mol%, MFR 4.1 g / 10 min (210 ° C., 2160 g), boric acid 300 ppm (in terms of boron)].

[Production of EVOH resin composition]
As EVOH resin (A), the content of the ethylene structural unit obtained above was 37 mol%, the saponification degree was 99.7%, MFR 4.1 g / 10 min (210 ° C., load 2160 g), side chain 1,2- A diol structural unit (1a) content of 1.5 mol% was used.
As the ethylene-α-olefin copolymer (B), an acid-modified ethylene-α-olefin copolymer (trade name “MA8510” manufactured by Mitsui Chemicals) and an unmodified ethylene-α-olefin copolymer (Mitsui, Ltd.) Uses a mixture of “Chemical Co., Ltd. trade name“ A4085 ”) (acid-modified ethylene-α-olefin copolymer / unmodified ethylene-α-olefin copolymer (weight ratio) = 3.5 / 1.5). It was.
95 parts of (A) and 5 parts of (B) are pre-blended and then charged into a feeder, melt-kneaded in a twin-screw extruder having two mixing zones under the following conditions, extruded into a strand, and a drum type pelletizer To obtain cylindrical pellets of the resin composition of the present invention.
・ Two-screw extruder: Diameter 32 mm
・ Extruder set temperature:
C2 / C3 / C4 / C5 / C6 / C7 / C8 / C9 / C10 / C11 / C12 / C13 / C14 / C15 / C16 / H / D = 80/100/180/220/230/230/230/230 / After 220 ℃
・ Strand cooling: Water cooling

[Manufacture of single-layer film]
Next, the pellets were supplied to an extruder (40 mmΦ) equipped with a T die, the die was set to 220 ° C., and a single layer film having a thickness of 100 μm was formed. Extrusion molding conditions were set as follows.
・ Extruder set temperature: C1 / C2 / C3 / C4 / H / D = 200/220/220/220/220/220 ℃
・ Cooling roll temperature: 80 ℃

  The following evaluation was performed about the single layer film obtained above.

[Evaluation of heat seal strength]
The films obtained above were superposed and pressure-bonded for 1 second under the conditions of a temperature of 147 ° C. and a pressure of 0.2 MPa using a heat sealer (trade name “Heat Seal Tester” manufactured by Imoto Seisakusho Co., Ltd.).

The heat seal strength (N / 15 mm) per 15 mm width of the heat-sealed film was measured by an autograph (trade name “Autograph AGS-H” manufactured by Toyo Seiki Co., Ltd.).
The tensile speed at the time of measuring the seal strength was 300 mm / min.

<Comparative Example 1>
In Example 1, EVOH resin (A) / ethylene-α-olefin copolymer (B) = 90/10, and as the ethylene-α-olefin copolymer (B), acid-modified ethylene-α-olefin copolymer And a mixture of unmodified ethylene-α-olefin copolymer (acid-modified ethylene-α-olefin copolymer / unmodified ethylene-α-olefin copolymer (weight ratio) = 7/3) A film was prepared in the same manner as in Example 1 and evaluated in the same manner.

<Comparative Example 2>
In Example 1, a film was prepared in the same manner as in Example 1 except that the ethylene-α-olefin copolymer (B) was not contained, and evaluated in the same manner.

  The evaluation results of the heat seal strength are shown in Table 1.

  As can be seen from Table 1, when a resin composition containing a specific small amount of ethylene-α-olefin copolymer (B) is used as a heat-sealing layer in EVOH resin (A) (Example 1), heat The seal strength was high and good.

  On the other hand, when EVOH resin (A) alone is used as a heat-sealing layer (Comparative Example 2), a resin composition containing a large amount of ethylene-α-olefin copolymer (B) is used as a heat-sealing layer. When it was (Comparative Example 1), the heat seal strength was low.

  When the EVOH resin composition of the present invention is used as a heat-sealing layer, it has a good heat seal strength, and is therefore suitable as a resin composition used for a heat seal film.

Claims (4)

A resin composition comprising a saponified ethylene-vinyl ester copolymer (A) containing the following structural unit (1) and an ethylene-α-olefin copolymer (B), wherein the ethylene-vinyl ester copolymer A resin composition characterized in that the weight ratio (A) / (B) of the saponified coal (A) and the ethylene-α-olefin copolymer (B) is 98/2 to 92/8.

[Wherein R ¹ , R ² and R ³ each independently represents a hydrogen atom or an organic group, X represents a single bond or a bond chain, and R ⁴ , R ⁵ and R ⁶ each independently represent hydrogen. Indicates an atom or an organic group. ] The resin composition according to claim 1, wherein the ethylene-α-olefin copolymer (B) is a mixture of an acid-modified ethylene-α-olefin copolymer and an unmodified ethylene-α-olefin copolymer. object. A heat sealant comprising the resin composition according to claim 1. A heat seal film comprising a heat-sealing layer comprising the resin composition according to claim 1 as an innermost layer.