JP2006265440A - Polyethylene resin composition for extrusion laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyethylene resin composition which is used for extrusion laminates, has good molding processability, emits smoke in a reduced amount, when processed, has excellent heat resistance, excellent heat sealability, and further good cleanness, and is suitably used for uses such as container packaging materials for foods, drinks, medicines and the like, moisture-proof paper, and mold release paper. <P>SOLUTION: This a polyethylene resin composition for the extrusion laminates comprises linear polyethylene which has a density, a melt mass flow rate, and a mol.wt. distribution represented by the ratio of a weight-average mol.wt. to a number-average mol.wt. in specific ranges, respectively, and in which ≤100 methyl carbon atoms are contained in 1,000 carbon atoms of ethylenic polymers having converted mol.wts. of ≤10,000 in the linear polyethylene, and two kinds of high pressure low density polyethylene each having a density, a melt mass flow rate, and a melt tension ratio in specific ranges, respectively, and has a specific relation between the melt mass flow rate and the melt tension. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a polyethylene resin composition for extrusion lamination. More specifically, the moldability is good, the amount of fuming at the time of processing is small, in addition, it has excellent heat resistance, adhesiveness, heat sealability, and also has cleanness, for food, for beverages, The present invention relates to a polyethylene resin composition for extrusion laminating which is suitably used for applications such as containers and packaging materials for medicine, moisture-proof paper, release paper and the like.

It is well known to coat polyethylene onto a substrate such as paper, paperboard, cellophane, aluminum foil, polypropylene film, nylon film, PET film by extrusion lamination. Among these base materials, in the case of low moisture-proof base materials such as paper, paperboard, and cellophane, high-density polyethylene is used to provide moisture resistance and to increase the heat resistance of the coated polyethylene. It is used alone or mixed with low density polyethylene or medium density polyethylene. However, in such a case, problems such as occurrence of surging, thickness fluctuation due to draw resonance, tendency to increase in neck-in, and decrease in adhesion to the substrate have been caused. A method for solving these problems has been proposed in, for example, Patent Document 1, and in addition, Patent Document 2 discloses a method for improving adhesion and suppressing the amount of smoke generated during processing.
However, with these methods, even though heat resistance, adhesiveness, and smoke generation are improved, there is a problem that heat sealability is impaired, and after heat sealing, heat treatment, and after sterilization and sterilization by irradiation with ultraviolet rays and radiation. The problem remains that the recent high demands for cleanliness, such as odors, are not adequately met.

Japanese Patent Laid-Open No. 06-190983 Japanese Patent No. 3005194

  The present invention has been made in view of the above circumstances, has good moldability, has a small amount of smoke during processing, and also has excellent heat resistance, adhesiveness, and heat sealability. Furthermore, an object of the present invention is to provide a polyethylene resin composition for extrusion laminating which is suitable for uses such as food packaging, beverages, pharmaceutical containers and packaging materials, moisture-proof paper, release paper, etc., which also have clean properties. To do.

  The present inventors have good molding processability, a small amount of smoke during processing, in addition, excellent heat resistance, adhesiveness, heat sealability, and also cleanliness, for foods and beverages As a result of extensive research to develop a polyethylene resin composition for extrusion laminating that can be suitably used for containers, packaging materials for medicine, moisture-proof paper, release paper, etc., a specific polyethylene resin composition is used. As a result, the present inventors have found that the above object is met, and have completed the present invention based on this finding.

That is, the present invention is as follows.
[1] A resin composition comprising linear polyethylene and high-pressure low-density polyethylene, wherein the linear polyethylene has a density of 930 kg / m ³ or more and a melt mass flow rate of 0.1 g / 10 min to 50 g / 10 min. The carbon atom of an ethylene polymer having a molecular weight distribution expressed by a ratio of a weight average molecular weight to a number average molecular weight of 2 or more and 10 or less, and a converted molecular weight in the linear polyethylene obtained by gel permeation chromatography of 10,000 or less. The linear polyethylene (A) in which the number of methyl carbon atoms contained in 1000 is 100 or less, the high-pressure low-density polyethylene is 935 kg / m ³ or less, and the melt mass flow rate is 0.3 g / 10 min or more and 10. 0 g / 10 min or less, the melt tension ratio represented by the following formula (1) is 0.7 or more, A high-pressure low-density polyethylene (B) in which the relationship between the lut mass flow rate ratio and the melt tension satisfies the following formula (2), a density of 935 kg / m ³ or less and a melt mass flow rate of 0.3 g / 10 min to 10.0 g / 10 minutes or less, the melt tension ratio represented by the following formula (1) is 0.6 or less, and the relationship between the melt mass flow rate ratio and the melt tension is the high pressure method low density polyethylene (C) satisfying the following formula (3), The linear polyethylene (A) is 20 parts by weight or more and 95 parts by weight or less, and the total of the high pressure method low density polyethylene (B) and the high pressure method low density polyethylene (C) is 80 parts by weight or less, and the high pressure method low density. A polyethylene resin composition for extrusion lamination, wherein the weight ratio of polyethylene (B) and high-pressure low-density polyethylene (C) is from 1/99 to 99/1.
MTR = (MT ₂₄₀ ° C.) / (MT ₁₉₀ ° C.) (1)
(MT ₁₉₀ ° C.) ≧ 0.65 (FRR) −20 (2)
(MT ₁₉₀ ° C.) ≦ 0.65 (FRR) −25 (3)
In the above formulas (1), (2) and (3), MTR represents the melt tension ratio, MT represents the melt tension, MT subscript represents the melt tension measurement temperature, and FRR represents the melt mass flow rate ratio.
[2] The polyethylene resin composition for extrusion lamination according to the above [1], wherein the linear polyethylene is obtained by a polymerization method using a supported geometrically constrained single site catalyst.
[3] The polyethylene resin composition for extrusion lamination according to the above [1], wherein the polyethylene resin composition does not contain a filler, slip agent, or antioxidant additive.

  According to the present invention, the molding processability is good, the amount of smoke generated at the time of processing is small, and in addition, it has excellent heat resistance and adhesiveness, heat sealing properties, and after heat sealing, heat treatment, ultraviolet rays / radiation Suitable for food and beverage container packaging materials including dairy products, pharmaceutical container packaging materials, moisture-proof paper, release paper, etc. that have low odor after sterilization and sterilization processing due to irradiation It was possible to provide a polyethylene resin composition for extrusion lamination used in the above.

Hereinafter, the present invention will be described in detail.
The linear polyethylene in the polyethylene resin composition for extrusion lamination of the present invention has a density of 930 kg / m ³ or more, preferably 932 kg / m ³ or more, and a melt mass flow rate (hereinafter abbreviated as MFR) of 0.1 g / 10 min or more. 50 g / 10 min or less, preferably 0.3 g / 10 min or more and 40 g / 10 min or less, the molecular weight distribution represented by the ratio of the weight average molecular weight to the number average molecular weight is 2 or more and 10 or less, preferably 3 or more and 7 or less, The number of methyl carbon atoms (hereinafter, methyl group) contained in 1000 carbon atoms of the ethylene polymer having a converted molecular weight of 10,000 or less in the linear polyethylene obtained by gel permeation chromatography (hereinafter abbreviated as GPC). The concentration is abbreviated as 100) or less (hereinafter, the methyl group concentration is expressed as number / 100 0 (C).), Preferably 80/1000 (C) or less.

The problems when the density, MFR, molecular weight distribution, and methyl group concentration of the linear polyethylene in the polyethylene resin composition for extrusion lamination of the present invention are outside the above ranges will be described below. If the density is less than 930 kg / m ³ , the heat sealability is good, but sufficient heat resistance cannot be obtained. When the MFR is less than 0.1 g / 10 min, the drawdown property is lowered. When the MFR is more than 50 g / 10 min, the neck-in is increased, and the moldability is lowered in any case. Further, when the molecular weight distribution is less than 2, there are problems that the extrusion load at the time of molding becomes large and the effect of improving the heat resistance is not sufficient, and when it exceeds 10, the amount of smoke generated at the time of molding is increased. In addition, if the methyl group concentration exceeds 100/1000 (C), the amount of smoke generated during molding increases, and the low odor properties after heat sealing, heat treatment, and sterilization / sterilization processing by UV / radiation irradiation are impaired. It will be said. As described above, the linear polyethylene in the polyethylene resin composition for extrusion lamination of the present invention is reduced in the amount of smoke generated during molding, improved heat resistance, and sterilized after heat sealing, heat treatment, and irradiation with ultraviolet rays and radiation. -From the viewpoint of low odor after sterilization, the density, MFR, molecular weight distribution, and methyl group concentration must be within the above ranges.

High-pressure low-density polyethylene in the extrusion laminating a polyethylene resin composition of the present invention has a density of 935 kg / m ³ or less, preferably 932kg / m ³ or less, MFR is 0.3 g / 10min or higher 10.0 g / 10min or less, Preferably, the melt tension ratio (hereinafter abbreviated as MTR) represented by the following formula (1) is 0.7 or more, preferably 0.8 or more, and the melt mass flow is 0.4 g / 10 min or more and 8.0 g / 10 min or less. A high-pressure low-density polyethylene (B) in which the relationship between the rate ratio (hereinafter abbreviated as FRR) and the melt tension (hereinafter abbreviated as MT) satisfies the following formula (2), a density of 935 kg / m ³ or less, preferably at 932kg / m ³ or less, MFR is 0.3 g / 10min or higher 10.0 g / 10min or less, preferably 0.4 g / 10min or more 8.0 g / 0 min or less, MTR represented by the following formula (1) is 0.6 or less, preferably 0.5 or less, and the relationship between FRR and MT satisfies the following formula (3) and is made of a high pressure method low density polyethylene (C). .
MTR = (MT ₂₄₀ ° C.) / (MT ₁₉₀ ° C.) (1)
(MT ₁₉₀ ° C.) ≧ 0.65 (FRR) −20 (2)
(MT ₁₉₀ ° C.) ≦ 0.65 (FRR) −25 (3)
Here, in the above formulas (1), (2), and (3), the subscript of MT represents the measured temperature of MT.

The problems when the density, MFR, molecular weight distribution, and methyl group concentration of the high-pressure low-density polyethylene in the polyethylene resin composition for extrusion lamination of the present invention are outside the above ranges are shown in the high-pressure low-density polyethylene (B), (C ) Is described below. If the density of the high pressure method low density polyethylene (B) exceeds 935 kg / m ³ , a sufficient neck-in improving effect cannot be obtained. When the MFR is less than 0.3 g / 10 min, the draw-down property is lowered. On the other hand, when the MFR is more than 10.0 g / min, the neck-in is increased, and none of them can realize good moldability. If the MTR is less than 0.7, the neck-in at the time of high-temperature molding becomes large, and stable molding cannot be performed. Furthermore, if the above formula (2) cannot be satisfied, both good neck-in and draw-down properties cannot be achieved, and excellent moldability cannot be obtained.

On the other hand, if the density of the high-pressure method low-density polyethylene (C) exceeds 935 kg / m ³ , the heat sealability is lowered. If the MFR is less than 0.3 g / 10 min, good adhesion cannot be obtained, and if it exceeds 10.0 g / min, the neck-in becomes small and surging tends to occur. When MTR exceeds 0.6, the fluidity at the time of high-temperature molding is lowered, and the problem that the effect of improving adhesiveness is reduced occurs. Further, if the above formula (3) cannot be satisfied, it is impossible to achieve both improvement in molding processability such as neck-in and surging and improvement in adhesion. As described above, the high pressure method low density polyethylene in the polyethylene resin composition for extrusion laminating of the present invention has the density, MFR, MTR and the like from the viewpoint of improvement in molding processability such as neck-in and drawdown properties, heat sealability, and adhesiveness. The relationship between FRR and melt tension needs to be in the above range.

  In the polyethylene resin composition for extrusion lamination of the present invention, the linear polyethylene (A) is 20 to 95 parts by weight, preferably 25 to 90 parts by weight, high pressure method low density polyethylene (B) and high pressure method. The total of the low density polyethylene (C) is 80 parts by weight or less and 5 parts by weight or more, preferably 75 parts by weight or less and 10 parts by weight or more. The weight of the high pressure method low density polyethylene (B) and the high pressure method low density polyethylene (C) The ratio is from 1/99 to 99/1, preferably from 5/95 to 95/5. If the amount of linear polyethylene (A) is less than 20 parts by weight, sufficient heat resistance improvement effect cannot be obtained, and low odor after heat sealing, heat treatment, and sterilization / sterilization by irradiation with ultraviolet rays / radiation is reduced. However, when the amount exceeds 95 parts by weight, there is a problem that neck-in is large and surging is likely to occur. If the mixing ratio of the high pressure method low density polyethylene (B) and the high pressure method low density polyethylene (C) is less than 1/99, improvement in molding processability such as neck-in and draw-down properties cannot be realized. If it exceeds 1, good heat sealability and excellent adhesion cannot be obtained. The mixing method of the linear polyethylene (A), the high pressure method low density polyethylene (B), and the high pressure method low density polyethylene (C) may be either dry blend or melt blend.

The linear polyethylene in the polyethylene resin composition for extrusion lamination of the present invention needs to be obtained by a polymerization method of polyethylene using a supported geometrically constrained single site catalyst. Various known methods can be used as the polymerization method, for example, fluidized bed gas phase polymerization in an inert gas, or stirring gas phase polymerization, slurry polymerization in an inert solvent, bulk polymerization using a monomer as a solvent, etc. However, slurry polymerization in an inert solvent is preferable.
The linear polyethylene of the present invention may be a polymer composed of ethylene alone or a copolymer composed of ethylene and an α-olefin having 3 to 20 carbon atoms, and has a carbon number of 3 to be copolymerized with ethylene. As the 20 α-olefins, propylene, butene-1, pentene-1, hexene-1, octene-1, decene-1, dodecene-1, tetradecene-1, hexadecene-1, octadecene-1, eicosene-1, Examples include 3-methyl-butene-1, 4-methyl-pentene-1, 6-methyl-heptene-1. Two or more of these may be dry blended or melt blended at an arbitrary ratio.

The supported geometrically constrained single-site catalyst (hereinafter abbreviated as metallocene catalyst) used in the above polymerization method is (a) a carrier material, (b) an organoaluminum, and (c) a cyclic η-binding anion coordination. And (d) an activator capable of reacting with the transition metal compound having the cyclic η-bonding anion ligand to form a complex that exhibits catalytic activity. Japanese Patent Laid-Open No. 11-166209 discloses that titanium is used as a transition metal atom in the transition metal compound having a cyclic η-bonding anion ligand (c).
The carrier substance (a) may be either an organic carrier or an inorganic carrier. The organic carrier is preferably (1) an α-olefin polymer having 2 to 20 carbon atoms, such as ethylene resin, propylene resin, butene-1 resin, ethylene-propylene copolymer resin, ethylene-hexene-1. Copolymer resins, propylene-butene-1 copolymer resins, ethylene-hexene-1 copolymers, etc. (2) aromatic unsaturated hydrocarbon copolymers such as styrene resins, styrene-divinylbenzene copolymers And (3) polar group-containing polymer resins such as acrylic ester resins, methacrylic ester resins, acrylonitrile resins, vinyl chloride resins, amide resins, and carbonate resins.

As the inorganic carrier, (4) as the inorganic oxide, _{e.g., SiO 2, Al 2 O 2} , MgO, TiO 2, B 2 O 3, CaO, ZnO, BaO, ThO, SiO 2 -MgO, SiO 2 -Al ₂ O ₃ , SiO ₂ —MgO, SiO ₂ —V ₂ O _5, etc. (5) As inorganic halogen compounds, for example, MgCl ₂ , AlCl ₃ , MnCl _2, etc. (6) Inorganic carbonates, sulfates, nitrates As, for example, Na ₂ CO ₃ , K ₂ CO ₃ , CaCO ₃ , MgCO ₃ , Al ₂ (SO ₄ ) ₃ , BaSO ₄ , KNO ₃ , Mg (NO ₃ ) ₂ , (7) As a hydroxide, For example, Mg (OH) ₂ , Al (OH) ₃ , Ca (OH) _{3 and the} like are exemplified. The most preferred carrier is SiO _2.
The particle size of the carrier is arbitrary, but generally 1 μm to 3000 μm, and from the viewpoint of particle dispersibility, the particle shape distribution is preferably in the range of 10 to 1000 μm.

The carrier material is treated with (a) an organoaluminum compound as necessary. As a preferred organoaluminum compound, a linear or cyclic polymer represented by the general formula (—Al (R) O—) n (R is a hydrocarbon group having 1 to 10 carbon atoms, and partially halogenated atoms and And / or those substituted with an RO group, where n is the degree of polymerization and is 5 or more, preferably 10 or more.) Specific examples include R as a methyl group, an ethyl group, and an isobutylethyl group. Examples thereof include methylalumoxane, ethylalumoxane, isobutylethylalumoxane, and the like.
Still other organoaluminum compounds include trialkyl aluminum, dialkyl halogeno aluminum, sesquialkyl halogeno aluminum, armenyl aluminum, dialkyl hydroaluminum, sesquialkyl hydroaluminum and the like.

  Specific examples of other organoaluminum compounds include trialkylaluminum such as trimethylaluminum, triethylaluminum, triisobutylaluminum, trihexylaluminum, and trioctylaluminum, dialkylhalogenoaluminum such as dimethylaluminum chloride and diethylaluminum chloride, and sesquimethylaluminum. Examples thereof include sesquialkyl halogenoaluminums such as chloride and sesquiethylaluminum chloride, ethylaluminum dichloride, diethylaluminum hydride, diisobutylaluminum hydride, and sesquiethylaluminum hydride. Of these, trimethylaluminum, triethylaluminum, triisobutylaluminum, diethylaluminum hydride and diisobutylaluminum hydride are most preferred.

式中、Ｍは１つ以上の配位子Ｌとη⁵結合をしている酸化数＋２、＋３、＋４の長周期型周期律表第４族遷移金属であり、特に遷移金属としてはチタニウムが好ましい。
又、Ｌは環状η結合性アニオン配位子であり、各々独立にシクロペンタジエニル基、インデニル基、テトラヒドロインデニル基、フルオレニル基、テトラヒドロフルオレニル基、またはオクタヒドロフルオレニル基であり、これらの基は２０個までの非水素原子を含む炭化水素基、ハロゲン、ハロゲン置換炭化水素基、アミノヒドロカルビ基、ヒドロカルビオルオキシ基、ジヒドロカルビルアミノ基、ジヒドロカルビルフォスフィノ基、シリル基、アミノシリル基、ヒドロカルビルオキシシリル基及びハロシリル基から各々独立に選ばれる１〜８の置換基を任意に有していてもよく、さらには２つのＬが２０個までの非水素原子を含むヒドロカルバジイル、ハロヒドロカルバジイル、ヒドロカルビレンオキシ、ヒドロカルビレンアミノ、ジラジイル、ハロシラジイル、アミノシランなどの２価の置換基により結合されていてもよい。 The supported catalyst includes, for example, a transition metal compound having (u) a cyclic η-bonding anion ligand represented by the following formula (4).

In the formula, M is a group 4 transition metal of a long-period type periodic table having an oxidation number of +2, +3, +4 and having an η ⁵ bond with one or more ligands L. preferable.
L is a cyclic η-bonding anion ligand, each independently a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, a fluorenyl group, a tetrahydrofluorenyl group, or an octahydrofluorenyl group. These groups are hydrocarbon groups containing up to 20 non-hydrogen atoms, halogens, halogen-substituted hydrocarbon groups, aminohydrocarbyl groups, hydrocarbyloxy groups, dihydrocarbylamino groups, dihydrocarbylphosphino groups, silyl groups Optionally having 1 to 8 substituents each independently selected from an aminosilyl group, a hydrocarbyloxysilyl group, and a halosilyl group, and further two hydrocarbyls containing up to 20 non-hydrogen atoms. Diyl, halohydrocarbadiyl, hydrocarbyleneoxy, hydrocarbyleneamino, dill Yl, Haroshirajiiru, may be linked by a divalent substituent such as an aminosilane.

Each X independently represents a monovalent anionic σ-bonded ligand having up to 60 non-hydrogen atoms, a divalent anionic σ-bonded ligand that binds to M divalently, or M and It is a divalent anion σ-bonded ligand that binds to L with one valence each.
X ′ is each independently a neutral Lewis base coordination compound selected from phosphine, ether, amine, olefin and / or conjugated diene having 4 to 40 carbon atoms.
L is an integer of 1 or 2. p is an integer of 0, 1 or 2, and X is a monovalent anionic σ-bonded ligand or a divalent anionic σ-bonded configuration in which M and L are each bonded with a single valence. When it is a ligand, p is 1 or less less than the formal oxidation number of M, or when X is a divalent anionic σ-bonded ligand that binds to M in a divalent manner, p is smaller than the formal oxidation number of M. Is also less than l + 1. Q is 0, 1 or 2. The transition metal compound is preferably 1 = 1 in the above formula (4).

式中、Ｍは形式酸化数＋２、＋３又は＋４のチタニウム、ジルコニウム、ハフニウムであり、特にチタニウムが好ましい。 For example, a suitable example of the transition metal compound is represented by the following formula (5).

In the formula, M is titanium, zirconium or hafnium having a formal oxidation number of +2, +3 or +4, and titanium is particularly preferable.

Also, each R ³ is independently hydrogen, hydrocarbon group, silyl group, germyl group, cyano group, halogen, or a composite machine thereof, and each can have up to 20 non-hydrogen atoms. Further, adjacent R ³ may be cyclic by forming a divalent derivative such as hydrocarbadiyl, diradii, or germanidyl.
X ″ each independently represents a halogen, a hydrocarbon group, a hydrocarbyloxy group, a hydrocarbylamino group, or a silyl group, each having up to 20 non-hydrogen atoms, and two X ″ having 5 to 5 carbon atoms Thirty neutral conjugated dienes or divalent derivatives may be formed.
Y is, -O -, - S -, - NR * -, - PR * - a and, Z is _{^{SiR * 2, CR * 2,}} SiR * 2 SiR * 2, CR * 2 CR * 2, CR * = CR ^* , CR ^* ₂ SiR ^* ₂ or GeR ^* ₂ , where R ^* is each independently an alkyl or aryl group having 1 to 12 carbon atoms. N is an integer of 1 to 3.

Furthermore, as a more suitable example as a transition metal compound, it represents with following formula (6) and following formula (7).

In the formula, each R ³ is independently hydrogen, a hydrocarbon group, a silyl group, a germyl group, a cyano group, a halogen, or a composite machine thereof, and each can have up to 20 non-hydrogen atoms. The transition metal M is titanium, zirconium or hafnium, with titanium being preferred.
The definitions of Z, Y, X and X ′ are as described above. p is 0, 1 or 2, and q is 0 or 1. However, when p is 2 and q is 0, the oxidation number of M is +4, and X is halogen, hydrocarbon group, hydrocarbyloxy group, dihydrocarbylamino group, dihydrocarbyl phosphide group, hydrocarbyl sulfide group, silyl group Group or a composite group thereof, having up to 20 non-hydrogen atoms.
When p is 1 and q is 0, the oxidation number of M is +3, and X is an allyl group, 2- (N, N-dimethylaminomethyl) phenyl group or 2- (N, N-dimethyl). -A stabilized anionic ligand selected from aminobenzyl groups, or the oxidation number of M is +4 and X is a derivative of a divalent conjugated diene, or both M and X are metallocyclopentene groups Is forming.
In addition, when p is 0 and q is 1, the oxidation number of M is +2, and X ′ is a neutral conjugated or non-conjugated diene, optionally substituted with one or more hydrocarbons. Also, the X ′ may contain up to 40 carbon atoms and forms a π-type complex with M.

Furthermore, in the present invention, the most suitable examples of the transition metal compound are represented by the following formula (8) and the following formula (9).

In the formula, each R ³ is independently hydrogen or an alkyl group having 1 to 6 carbon atoms. M is titanium, Y is -O-, -S-, -NR ^* -, -PR ^* -, and Z ^* is SiR ^* ₂ , CR ^* ₂ , SiR ^* ₂ SiR ^* ₂ , CR ^*. ₂ CR ^* ₂ , CR ^* = CR ^* , CR ^* ₂ SiR ₂ or GeR ^* ₂ , where R ^* is independently hydrogen, a hydrocarbon group, a hydrocarbyloxy group, a silyl group, or an alkyl halide. Group, a halogenated aryl group or a composite group thereof. The R ^* may have a non-hydrogen atoms up to 20, and optionally also have a Z ^* 2 one R ^* s or Z ^* R ^* is cyclic in R ^* and Y medium medium Good.
p is 0, 1 or 2, and q is 0 or 1. However, when p is 2 and q is 0, the oxidation number of M is +4, and X is each independently a methyl group or a hydrobenzyl group.
When p is 1 and q is 0, the oxidation number of M is +3 and X is a 2- (N, N-dimethyl) -aminobenzyl group, or the oxidation number of M is +4. And X is 2-butene-1,4-diyl.
When p is 0 and q is 1, the oxidation number of M is +2, and X ′ is 1,4-diphenyl-1,3-butadiene or 1,3-pentadiene. The dienes are examples of asymmetric dienes that form metal complexes, and are actually mixtures of geometric isomers.
In addition, the metallocene catalyst includes (d) an activator that can form a complex that reacts with a transition metal compound and exhibits catalytic activity. Usually, in a metallocene catalyst, a complex formed by a transition metal compound and the above activator exhibits high olefin polymerization activity as a catalytically active species.

但し式中、［Ｌ−Ｈ］^d+はプロトン付与のブレンステッド酸であり、Ｌは中性ルイス塩基である。また［Ｍ_mＱ_t］^d-は相溶性の非配位性アニオンであり、Ｍは周期律表第５族乃至１５族から選ばれる金属またはメタロイドであり、Ｑは各々独立にヒドリド、ジアルキルアミド基、ハライド、アルコキサイド基、アリロキサイド基、炭化水素基、炭素数２０までの置換炭化水素基であり、またハライドであるＱは１個以下である。又ｍは１乃至７の整数であり、ｐは２乃至１４の整数であり、ｄは１〜７の整数であり、ｔ−ｍ＝ｄである。 As an activator, the compound represented by following formula (10) is mentioned, for example.

In the formula, [LH] ^{d +} is a Bronsted acid imparted with protons, and L is a neutral Lewis base. [M _m Q _t ] ^d- is a compatible non-coordinating anion, M is a metal or metalloid selected from Groups 5 to 15 of the periodic table, and Q is independently a hydride or dialkylamide. Group, halide, alkoxide group, allyloxide group, hydrocarbon group, substituted hydrocarbon group having up to 20 carbon atoms, and Q which is a halide is 1 or less. M is an integer of 1 to 7, p is an integer of 2 to 14, d is an integer of 1 to 7, and t−m = d.

但し式中、［Ｌ−Ｈ］^d+はプロトン付与のブレンステッド酸であり、Ｌは中性ルイス塩基である。また［Ｍ_mＱ_w（Ｇ_u（Ｔ−Ｈ）_r）_z］^d-は相溶性の非配位性アニオンであり、Ｍは周期律表第５族乃至１５族から選ばれる金属またはメタロイドであり、Ｑは各々独立にヒドリド、ジアルキルアミド基、ハライド、アルコキサイド基、アリロキサイド基、炭化水素基、炭素数２０までの置換炭化水素基であり、またハライドであるＱは１個以下である。又ＧはＭ及びＴと結合するｒ＋１の価数を持多価炭化水素基であり、ＴはＯ、Ｓ、ＮＲまたはＰＲであり、ここでＲはヒドロカルビル基、トリヒドロカルビルシリル基、トリヒドロカルビルゲルマニウム基、もしくは水素である。
又ｍは１〜７の整数であり、ｗは０〜７の整数であり、ｕは０または１の整数であり、ｒは１〜３の整数であり、ｚは１〜８の整数であり、ｗ＋ｚ−ｍ＝ｄである。 A more preferred example of the activator is a compound represented by the following formula (11).

In the formula, [LH] ^{d +} is a Bronsted acid imparted with protons, and L is a neutral Lewis base. Also a _{[M m Q w (G u} (T-H) r) z] d- is a non-coordinating anion compatible, M is a metal or metalloid selected from Group 5 to Group 15 of the periodic table Each Q is independently a hydride, a dialkylamide group, a halide, an alkoxide group, an allyloxide group, a hydrocarbon group or a substituted hydrocarbon group having up to 20 carbon atoms, and the Q as a halide is 1 or less. G is a polyvalent hydrocarbon group having a valence of r + 1 which binds to M and T, and T is O, S, NR or PR, where R is a hydrocarbyl group, a trihydrocarbylsilyl group, a trihydrocarbylgermanium. A group or hydrogen.
M is an integer of 1 to 7, w is an integer of 0 to 7, u is an integer of 0 or 1, r is an integer of 1 to 3, and z is an integer of 1 to 8. , W + z−m = d.

但し式中、［Ｌ−Ｈ］^d+はプロトン付与のブレンステッド酸であり、Ｌは中性ルイス塩基である。また［ＢＱ₃Ｑ^*］^-は相溶性の非配位性アニオンであり、Ｂはホウ素原子、Ｑはペンタフルオロフェニル基であり、Ｑ^*は置換基としてＯＨ基を１つ有する炭素数６〜２０の置換アリール基である。 A more preferred example of the activator is a compound represented by the following formula (12).

In the formula, [LH] ^{d +} is a Bronsted acid imparted with protons, and L is a neutral Lewis base. [BQ ₃ Q ^* ] ⁻ is a compatible non-coordinating anion, B is a boron atom, Q is a pentafluorophenyl group, Q ^* has 6 to 6 carbon atoms having one OH group as a substituent. 20 substituted aryl groups.

  Specific examples of non-coordinating anions include triphenyl (hydroxyphenyl) borate, diphenyl-di (hydroxyphenyl) borate, triphenyl (2,4-dihydroxyphenyl) borate, tri (p-tolyl) phenyl (hydroxyphenyl). ) Borate, tris (pentafluorophenyl) (hydroxyphenyl) borate, tris (2,4 dimethylphenyl) (hydroxyphenyl) borate, tris (3,5 dimethylphenyl) (hydroxyphenyl) borate, tris (3,5-di-) -Trifluoromethylphenyl) (hydroxyphenyl) borate, tris (pentafluorophenyl,) (2-hydroxyethyl) borate, tris (pentafluorophenyl,) (4-hydroxybutyl) borate, tris (pentafluoro) Phenyl,) (4-hydroxy-cyclohexyl) borate, tris (pentafluorophenyl,) (4- (4′-hydroxyphenyl) phenyl) borate, tris (pentafluorophenyl) (6-hydroxy-2-naphthyl) borate, etc. Most preferred is tris (pentafluorophenyl) (hydroxyphenyl) borate.

Specific examples of other preferable compatible non-coordinating anions include borates in which the hydroxy group of the borate exemplified above is replaced with NHR. Here, R is preferably a methyl group, an ethyl group or a tert-butyl group.
Specific examples of the proton-providing Bronsted acid include, for example, triethylammonium, tripropylammonium, tri (n-butyl) ammonium, trimethylammonium, tributylammonium, and tri (n-octyl) ammonium, diethylmethylammonium. , Dibutylmethylammonium, dibutylethylammonium, dihexylmethylammonium, dioctylmethylammonium, didecylmethylammonium, didodecylmethylammonium, ditetradecylmethylammonium, dihexadecylmethylammonium, dioctadecylmethylammonium, diicosylmethylammonium, Trialkyl group-substituted ammonium cations such as bis (hydrogenated tallow alkyl) methylammonium N, N-dimethylanilinium, N, N-diethylanilinium, N, N-2,4,6-pentamethylanilinium, N, N-dimethylbenzylanilinium, etc. Also suitable are N-dialkylanilinium cations.

  The polyethylene resin composition for extrusion lamination of the present invention does not contain a filler, slip agent, or antioxidant additive. Examples of the filler include aluminosilicate, talc, diatomaceous earth, kaolin, clay, and the slip agent includes aliphatic hydrocarbon, higher fatty acid, higher fatty acid metal salt, fatty acid ester of alcohol, wax, higher fatty acid amide, Examples thereof include silicone oil and rosin. Antioxidants include phenolic antioxidants and phosphorus antioxidants, but as phenolic antioxidants, 2,6-di-t-butyl-4-methylphenol (dibutylhydroxytoluene), n- Phosphorus oxidation such as octadecyl-3- (4-hydroxy-3,5-di-t-butylphenyl) propionate, tetrakis (methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate)) methane As the inhibitor, tetrakis (2,4-di-t-butylphenyl) -4,4′-biphenylene-di-phosphonite, tris (2,4-di-t-butylphenyl) phosphite, cyclic neopentane And tetraylbis (2,4-t-butylphenyl phosphite).

  Note that glycerin fatty acid ester as an antistatic agent and calcium stearate as a neutralizing agent may be contained. The term “containing” as used herein means blending the above various additives into the resin composition for the purpose of modifying, improving, or coloring the polyethylene resin composition, and is unavoidable during the production of the resin composition. In the case where a trace amount of additive is mixed in the catalyst, or in the case where a trace amount of catalyst or reaction initiator remains, it is not said that it is contained. Addition of fillers, slip agents, and antioxidants is not preferable because it causes a problem that it cannot be used as a container and packaging material for milk and dairy products.

  The polyethylene resin composition for extrusion laminating according to the present invention is used as a laminate by coating on various substrates. As the substrate, cellophane, ethylene resin, ethylene / vinyl acetate resin, PP resin, CPP resin, PET resin, Nylon resin, vinyl chloride resin, vinylidene chloride resin, vinyl alcohol resin, eval resin, styrene resin, acrylonitrile resin, carbonate resin, ionomer resin, ethylene / acrylic acid copolymer resin, ethylene / methacrylic acid copolymer resin, ethylene Films made of methyl acrylate copolymer resin, ethylene / methyl acrylate copolymer resin, ethylene / ethyl acrylate resin, etc. and their K coat type, aluminum vapor deposition type, silica vapor deposition type, alumina vapor deposition type, and fine paper, Door paper, glassine paper, various types of paper such parchment paper or the like, aluminum foil, and the like. Each base material may be used alone, or two or more base materials may be used in combination. As a method of laminating two or more kinds of substrates, a known method such as a dry lamination method, an extrusion lamination method, a wet lamination method, a hot melt lamination method, a coextrusion inflation molding method, or a coextrusion cast molding method may be adopted. it can.

  The polyethylene resin composition for extrusion laminating of the present invention is a confectionery / bread, cooked food, cooked intermediate product, agricultural products, livestock, marine products, kneaded products, various foods such as water products, oil products, dairy products, chilled food products, It is suitably used for retort foods, frozen foods, seasonings, water, juice, milk, alcoholic beverages such as sake, shochu, and other beverages, cooked rice, and containers and packaging materials such as pharmaceuticals, medical supplies, and agricultural chemicals. Among them, the polyethylene resin composition for extrusion laminating of the present invention can be molded without containing fillers, slip agents, and antioxidant additives, so that it can be used as a container packaging material for milk, dairy products, etc. Preferably used.

The present invention will be specifically described below using examples, but the present invention is not limited to these examples.
The physical property measurement method and evaluation method are as follows.
(1) Density The density was measured according to JIS-K-7112: 1999.
(2) Melt mass flow rate (MFR)
Measured according to JIS-K-7210: 1999 (temperature = 190 ° C., load = 2.16 kg).

(3) Molecular weight distribution The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) obtained from gel permeation chromatography (GPC) is defined as the molecular weight distribution.
GPC measurement is made by Waters; GPCV2000 is used, and columns are made by Showa Denko KK; UT-807 (1) and Tosoh KK; GMHHR-H (S) HT (2) are connected in series. And used under the conditions of mobile phase trichlorobenzene (TCB), column temperature 140 ° C., flow rate 1.0 ml / min, sample concentration 20 mg / 15 ml (TCB), sample dissolution temperature 140 ° C., sample dissolution time 2 hours. Calibration of molecular weight is made by Tosoh Co., Ltd .; the standard polystyrene Mw is 12 points in the range of 1,050 to 2,060,000, and the Mw of each standard polystyrene is multiplied by a coefficient 0.43 to obtain the molecular weight in terms of polyethylene. A primary calibration line was created from a plot of molecular weight in terms of polyethylene, and the molecular weight was determined.

(4) Methyl group concentration The methyl group concentration is attributed to the methylene group by performing infrared spectroscopic analysis of the eluted components by Perkin Elmer Co., Ltd .; FT-IR, 1760X in the above molecular weight distribution measurement. From the absorbance I (methylene) (absorption wave number: 2925 cm ^-1 ) and the absorbance I (methyl) attributed to the methyl group (absorption wave number: 2960 cm ^-1 ), the ratio between the two, I (methyl) / I (methylene) is converted to molecular weight Is obtained for each eluted component of 10,000 or less, then multiplied by the weight fraction of the eluted component, and summed up.
(5) Melt tension (MT)
Manufactured by Toyo Seiki Co., Ltd. equipped with a capillary with a diameter of 2.095 mm and a length of 8.0 mm; when a capillograph 1D is used, a polyethylene resin is extruded at 190 ° C. or 240 ° C. at 60 mm / min, and taken out at 2 m / min. Obtained by measuring the tension. The melt tension when extruded at 190 ° C. is expressed as MT ₁₉₀ ° C., and the melt tension when extruded at ₂₄₀ ° C. is expressed as MT ₂₄₀ ° C.

(6) Melt flow rate ratio (FRR)
The melt mass flow rate ratio is obtained by dividing the MFR (temperature = 190 ° C., load = 21.6 kg) defined by JIS-K-7210: 1999 by MFR (temperature = 190 ° C., load = 2.16). Can do.
(7) Neck-in Neck-in is a resin temperature of 320 ° C. using an extruder equipped with a screw of diameter = 65φ and L / D = 30, and an inner deckle type die of a gap 0.7 mm and a two-stage manifold. , Processing set width = 400mm, air gap = 130mm, processing speed = 60m / min, thickness = 20μm, extrusion lamination is performed on kraft paper with a basis weight of 75g / cm ² , the total value of both side neck-in is the processing setting The width was evaluated as “Excellent” within 20%: 、, Excellent within 25%: ○, Slightly inferior within 35%: Δ, Inferior over 35%: “x”.

(8) Drawdown property The drawdown property is evaluated by measuring the speed at which surging occurs by gradually increasing the speed from the processing speed of the neck-in evaluation, and 250 m / min or more is very excellent: Less than 250 m / min to 220 m / min or more is excellent: ○, less than 220 m / min to 190 m / min is slightly inferior: Δ, less than 190 m / min is inferior: x.
(9) Smoke amount Smoke components generated when extrusion lamination was performed under the same conditions as in the neck-in evaluation were collected by suction at the top of the T-die attached to the extruder and placed at a position 5 m away from the suction part. Rion Co., Ltd .; light scattering type automatic particle counter: measured with KC-01D. Out of the measured smoke components, if the amount of smoke components having a particle size of 0.3 μm or more is less than 10,000 per liter, it is very excellent: ◎ 10,000 to less than 20,000 If it is excellent, it is evaluated as ◯: Slightly inferior if it is 20,000 or more but less than 50,000: Δ If it is 50,000 or more, it is inferior: x.

(10) Heat resistance Except for the processing speed of 100 m / min, the extrusion-laminated resin-coated paper was cut into a 20 cm square under the same conditions as the neck-in evaluation, and this sample was left in an oven at 130 ° C. for 90 seconds. The number of pinholes was evaluated later. When the number of pinholes is 2 or less, it is very excellent: ◎ more than 2 to 5 or less is excellent: ○, more than 5 to 10 or less is slightly inferior: Δ, 11 or more is inferior: x evaluated.
(11) Heat sealability Resin-coated aluminum foil obtained by extrusion laminating under the same conditions as neck-in evaluation except that the processing speed is 80 m / min and the base material is aluminum foil with a thickness of 20 microns. The temperature was changed by 10 ° C., heat sealing was performed under the conditions of pressure = 0.2 MPa, time = 1 second, and a sample cut out with a width of 15 mm was used as a sample to conduct a tensile test at a tensile speed of 500 mm / min. When the seal strength is plotted against the seal temperature, the seal strength at 10 ° C. higher than the temperature at which the seal strength reaches equilibrium exceeds 3 N / 15 mm, and the temperature is 140 ° C. or less, the heat sealability is very excellent: ◎, heat sealability is excellent if it is above 140 ° C to 150 ° C: ○, heat sealability is slightly inferior if it is above 150 ° C to 160 ° C or less: Δ, heat sealability is inferior if it is above 160 ° C : X.

(12) Adhesiveness According to the test method of JIS-P-8112, resin-coated kraft paper obtained by extrusion laminating to kraft paper with a basis weight of 75 g / m ^{2 under} the same conditions as in the neck-in evaluation is used. Compressed air of 5 kg / cm ² is applied from the kraft paper side, and the adhesion is evaluated in the peeled state of the resin layer. If the area of the peeled portion is 0%, the adhesiveness is very excellent: ◎, the same area is 0% If it is more than less than 5%, the adhesion is excellent: ○, if the area is 5% or more to less than 20%, the adhesion is slightly inferior: Δ, if the area is 20% or more, the adhesion is inferior: X, evaluated as
(13) Low odor property Using a resin-coated aluminum foil for evaluating heat sealability, the resin-coated surface was irradiated with ultraviolet rays having an intensity of 700 mW / cm ² for 3 seconds, temperature = 180 ° C., pressure = 0.2 MPa, time = Four seconds sealed bag is produced by heat sealing under the condition of 1 second, and then heat treated at 50 ° C for 30 minutes to obtain a sample. The odor of this sample is sensorially evaluated by 10 panelists. If it is obtained from panelists of 8 or more that the odor is hardly changed compared with before ultraviolet irradiation, it is very excellent in low odor: ◎, and less than 8 is inferior: ×.

[Production of linear polyethylene using metallocene catalyst]
6.2 g (8.8 mmol) of triethylammonium tris (pentafluorophenyl) (4-hydroxyphenyl) borate was added to 4 liters of toluene and stirred at 90 ° C. for 30 minutes. Next, 40 ml of a 1 mol / l trihexylaluminum toluene solution was added to this solution and stirred at 90 ° C. for a minute. On the other hand, silica P-10 (manufactured by Fuji Silysia Co., Ltd .: trade name) was treated in a nitrogen stream at 500 ° C. for 3 hours, and the treated silica was placed in 1.7 l of toluene and stirred. The toluene solution of triethylammonium triethylammonium tris (pentafluorophenyl) (4-hydroxyphenyl) borate and trihexylaluminum was added to the silica slurry solution, and the mixture was stirred at 90 ° C. for 3 hours.

Next, 206 ml of a 1 mol / l trihexylaluminum toluene solution was added, and the mixture was further stirred at 90 ° C. for 1 hour. Thereafter, the supernatant was decanted with 90 ° C. toluene to remove excess trihexylaluminum. 0.218 mol / l of deep purple titanium (N-1,1-dimethylethyl) dimethyl (1- (1,2,3,4,5-eta) -2,3,4,5-tetramethyl-2 , 4-cyclopentadien-1-yl) silanaminate) ((2-) N- (η4-1,3-pentadiene) in 20 ml of ISOPAR TME (Exxon Chemical Co., USA) solution was added to the above mixture for 3 hours. The mixture was stirred to obtain a green metallocene catalyst.
The obtained metallocene catalyst was introduced into the polymerization reactor by bringing hydrogen into contact with the catalyst transfer line by supplying a necessary amount of hydrogen as a chain transfer agent, hexane as a solvent, ethylene as a monomer, and butene- 1 was used to supply each monomer so as to have a predetermined gas composition, and linear polyethylene was polymerized at a reaction temperature of 75 ° C. and a total pressure of 0.8 MPa. The obtained linear polyethylene was granulated by extrusion at 200 ° C. using an extruder (screw diameter: 65 mm, L / D = 28) manufactured by Nippon Steel Co., Ltd.

[Production of linear polyethylene using Ziegler catalyst]
A 15-liter reactor sufficiently purged with nitrogen was charged with 3 liters of trichlorosilane as a 2 mol / liter n-heptane solution, kept at 65 ° C. with stirring, and the composition formula AlMg ₆ (C ₂ H ₅ ) ₃ ( n-C ₄ H ₉ ) _6.4 (On-C ₄ H ₉ ) 7 liters (5 mol in terms of magnesium) of an organomagnesium component represented by _5.6 was added over 1 hour, and further 1 at 65 ° C. The reaction was allowed to stir for an hour. After completion of the reaction, the supernatant was removed and washed 4 times with 7 liters of n-hexane to obtain a solid material slurry. This solid was separated, dried and analyzed, and as a result, it contained 7.45 mmol of Mg per gram of the solid.
Of these, a slurry containing 500 g of solid was reacted with 0.93 liter of n-butyl alcohol 1 mol / liter n-hexane solution at 50 ° C. for 1 hour with stirring. After completion of the reaction, the supernatant was removed and washed once with 7 liters of n-hexane. This slurry was kept at 50 ° C., and 1.3 liters of n-hexane solution of 1 mol / liter of diethylaluminum chloride was added with stirring and reacted for 1 hour. After completion of the reaction, the supernatant was removed and washed twice with 7 liters of n-hexane. This slurry was kept at 50 ° C., 0.2 liter of n-hexane solution of 1 mol / liter of diethylaluminum chloride and 0.2 liter of n-hexane solution of 1 mol / liter of titanium tetrachloride were added and reacted for 2 hours. After completion of the reaction, the supernatant was removed and the solid catalyst was isolated and washed with hexane until no free halogen was detected. The solid catalyst had 2.3 wt% titanium.

Using the catalyst obtained above, linear polyethylene was produced in the following manner.
In a single stage polymerization process, polymerization was performed in a polymerization vessel having a volume of 230 l. The polymerization temperature is 86 ° C. and the polymerization pressure is 0.98 MPa. The Ziegler catalyst synthesized in this polymerization vessel was introduced at a rate of 0.3 g / hr, triisobutylaluminum at 15 mmol / hr, and hexane at a rate of 60 l / hr. To this, ethylene, hydrogen, and if necessary, butene-1 was introduced so as to have a predetermined gas composition, polymerization was performed, and the obtained linear polyethylene was manufactured by Nippon Steel Co., Ltd .; extruder (screw diameter 65 mm, L / D = 28), n-octadecyl-3- (4-hydroxy-3,5-di-t-butylphenyl) propionate and calcium stearate were added and extruded and granulated at 200 ° C. .

[Production of high-pressure low-density polyethylene]
High pressure low density polyethylene can be obtained by radical polymerization of ethylene in an autoclave type or tubular type reactor. Either type may be used, but high pressure method low density polyethylene (B) is autoclave type, The high-pressure low-density polyethylene (C) is preferably obtained by polymerization in a tubular type. When an autoclave type reactor is employed, the polymerization conditions may be set to a temperature of 200 to 300 ° C. and a polymerization pressure of 100 to 250 MPa in the presence of peroxide, while a tubular type reactor is employed. In this case, the polymerization conditions may be set to a polymerization reaction peak temperature of 180 to 400 ° C. and a polymerization pressure of 100 to 400 MPa in the presence of a peroxide and a chain transfer agent, but a polymerization reaction peak temperature of 200 to 350 ° C. The polymerization pressure is preferably 150 to 350 MPa.

[Method for producing polyethylene resin composition comprising linear polyethylene and high-pressure low-density polyethylene]
The linear polyethylene obtained by the above production method and the high pressure method low density polyethylene were dry blended at a predetermined weight ratio, and extruded and granulated at 200 ° C. using a 65 mmφ extruder.
[Examples 1 to 5]
A polyethylene resin obtained by melt-blending the linear polyethylene obtained by the production method of linear polyethylene with the metallocene catalyst described above and the high-pressure low-density polyethylene described in Table 1 with the gas composition of ethylene, butene-1 and hydrogen described in Table 1. The composition was extrusion laminated at a resin temperature of 320 ° C. The evaluation results of molding processability, heat resistance, heat sealability, and low odor properties are also shown in Table 1.

[Comparative Example 1]
Polyethylene obtained by obtaining linear polyethylene by the gas composition of ethylene, butene-1 and hydrogen described in Table 2 and the above-described method for producing linear polyethylene using a titanium catalyst, and then melt blending with high-pressure low-density polyethylene The resin composition was extrusion laminated at a resin temperature of 320 ° C. Table 2 also shows the evaluation results of molding processability, heat resistance, heat sealability and low odor.
[Comparative Examples 2 to 4]
Gas composition of ethylene, butene-1 and hydrogen listed in Table 2, and linear polyethylene obtained by the method of producing linear polyethylene using the metallocene catalyst brought into contact with hydrogen and high pressure low density polyethylene listed in Table 2. A polyethylene resin composition obtained by melt blending was extruded and laminated at a resin temperature of 320 ° C. Table 2 also shows the evaluation results of molding processability, heat resistance, heat sealability and low odor.

  Since the polyethylene resin composition for extrusion laminating of the present invention exhibits the above-mentioned effects, confectionery / bread, cooked food, cooked intermediate products, agricultural products, livestock products, marine products, kneaded products, water products, oil products, dairy products, etc. Various foods, chilled foods, retort foods, frozen foods, seasonings, water, juice, milk, various beverages such as sake, shochu and other alcoholic beverages, cooked rice, and containers and packaging materials such as pharmaceuticals, medical supplies and agricultural chemicals Preferably used. Especially, it is used suitably as container packaging materials, such as milk and dairy products.

Claims (3)

A resin composition comprising linear polyethylene and high-pressure low-density polyethylene, wherein the linear polyethylene has a density of 930 kg / m ³ or more, a melt mass flow rate of 0.1 g / 10 min to 50 g / 10 min, number average molecular weight The molecular weight distribution represented by the ratio of the weight average molecular weight to the molecular weight is 2 or more and 10 or less, and the converted molecular weight in the linear polyethylene obtained by gel permeation chromatography is 1000 carbon atoms of an ethylene polymer having a molecular weight of 10,000 or less. A linear polyethylene (A) having 100 or less methyl carbon atoms and a high-pressure low-density polyethylene having a density of 935 kg / m ³ or less and a melt mass flow rate of 0.3 g / 10 min to 10.0 g / 10 min Hereinafter, the melt tension ratio represented by the following formula (1) is 0.7 or more, A high-pressure low-density polyethylene (B) in which the relationship between the sflow rate ratio and the melt tension satisfies the following formula (2), a density of 935 kg / m ³ or less, and a melt mass flow rate of 0.3 g / 10 min to 10.0 g / 10 minutes or less, the melt tension ratio represented by the following formula (1) is 0.6 or less, and the relationship between the melt mass flow rate ratio and the melt tension is the high pressure method low density polyethylene (C) satisfying the following formula (3), The linear polyethylene (A) is 20 parts by weight or more and 95 parts by weight or less, and the total of the high pressure method low density polyethylene (B) and the high pressure method low density polyethylene (C) is 80 parts by weight or less, and the high pressure method low density. A polyethylene resin composition for extrusion lamination, wherein the weight ratio of polyethylene (B) and high-pressure low-density polyethylene (C) is from 1/99 to 99/1.
MTR = (MT ₂₄₀ ° C.) / (MT ₁₉₀ ° C.) (1)
(MT ₁₉₀ ° C.) ≧ 0.65 (FRR) −20 (2)
(MT ₁₉₀ ° C.) ≦ 0.65 (FRR) −25 (3)
In the above formulas (1), (2) and (3), MTR represents the melt tension ratio, MT represents the melt tension, MT subscript represents the melt tension measurement temperature, and FRR represents the melt mass flow rate ratio.   2. The polyethylene resin composition for extrusion lamination according to claim 1, wherein the linear polyethylene is obtained by a polymerization method using a supported geometrically constrained single site catalyst.   2. The polyethylene resin composition for extrusion laminating according to claim 1, wherein the polyethylene resin composition does not contain a filler, slip agent, or antioxidant additive.