JP2003201377A - Easily tearable film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use an ethylene resin mainly composed of ethylene, to have excellent film formability such as T-die molding, to have excellent stretchability in all directions without stretching, and to have an appropriate tear strength. To provide an ethylene-based resin having excellent tearability and a non-stretched, non-stretchable, excellent cutability in all directions, an appropriate tear strength, and a film or packaging material excellent in tearability, which are obtained from such resins. With the goal. SOLUTION: In the presence of a metallocene catalyst, 80 to 99.9 mol% of ethylene and 0.1 to 1-butene are used.
20 mol% and α- of 3 to 12 carbon atoms (excluding 4 carbon atoms)
Density, melt flow rate and melt tension of ethylene / 1-butene copolymer in a specific range obtained by copolymerizing olefin with 0 to 10 mol% 55 to 100% by weight
And an easily tearable film comprising a composition containing 0 to 45% by weight of an olefin polymer.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an easily tearable film mainly composed of an ethylene / 1-butene copolymer having specific characteristics containing ethylene and 1-butene. This easily tearable film is excellent in low-temperature heat sealability, adhesive strength of the seal portion, etc., and easily tearable film such as packaging bags and packaging materials for food, confectionery, snacks, chemicals, cutting tape, standing pouches, tubes, etc. Can be used as

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 8-188680 discloses
(A) 30 to 80% by weight of a high-pressure low-density polyethylene resin having a melt flow rate of 0.01 to 1 g / 10 minutes and a density of 0.910 to 0.925 g / cm ³ .
(B) Melt flow rate is 0.03 to 0.7 g / 10
Min, a high density polyethylene resin having a density of 0.940 to 0.970 g / cm ³ and / or a melt flow rate of 0.01 to 7.0 g / 10 min and a density of 0.91.
0 to 0.935 g / cm ³ and 0 to 40% by weight of a linear low density polyethylene resin in which the comonomer is an α-olefin having 4 or more carbon atoms, and (C) an average particle size of 0.5 to 6 μm Disclosed is an inorganic-filled polyethylene resin composition for a tape substrate, which is characterized by being blended with 20 to 60% by weight of treated heavy calcium carbonate.

Japanese Unexamined Patent Publication No. 8-295745 (A)
(A) It is obtained by (co) polymerizing an α-olefin in the presence of a catalyst containing a transition metal compound of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton as an essential component ( ) Melt florate 0.01-1
Α-Olefin (co) polymer 10 having an amount of 00 g / 10 minutes
0 to 20% by weight and (B) other olefin polymer 0 to
Disclosed is an easily tearable packaging material, which is a film-oriented packaging material comprising 80% by weight, wherein the infrared dichroic ratio of the packaging material is 1.2 or more. There is.

In Japanese Unexamined Patent Publication No. 2001-064456, 50 to 90% by weight of an ethylene-α-olefin copolymer produced from a metallocene catalyst having the following characteristic (A) and a high-pressure low density polyethylene having the following characteristic (B) are disclosed. 50 to 10% by weight
An easily tearable film comprising a composition comprising and is disclosed. (A) Ethylene-α-olefin copolymer produced from metallocene catalyst: (A-1) Density is 0.925 to 0.960 g / cm ³ . (A-2) Melt flow rate (MFR) is 0.1 to 1
00g / 10 minutes. (B) High-pressure method low-density polyethylene: (B-1) Density is 0.920 to 0.935 g / cm ³ . (B-2) Melt flow rate (MFR) is 0.1 to 1
00g / 10 minutes.

Japanese Unexamined Patent Publication Nos. 6-65442 and 6-
JP-A-206939 and JP-A-6-207056 disclose an inflation-molded film using a specific ethylene-butene-1 copolymer.

[0006]

[Problems to be Solved by the Invention] As a packaging material used for packaging bags and cut tapes for foods, confectionery, snacks, chemicals, etc., standing pouches, tubes, etc. As a processed film such as uniaxially stretched polyolefin such as polyethylene. It is used. Such packaging materials are required to have improved openability. It is considered that in an easily tearable packaging material using a stretched film, the stretched direction is excellent in easy tearability, and the unstretched direction is inferior in easy tearability. Further, in the case of an unstretched polyethylene film, the film may be easily stretched and inferior in tearability at the time of cutting. INDUSTRIAL APPLICABILITY The present invention uses an ethylene resin mainly composed of ethylene, is excellent in film moldability such as T-die molding, is excellent in cutability in all directions without stretching, has appropriate tear strength, and is excellent in easy tearability. An object of the present invention is to provide a resin and a film or packaging material obtained from these resins, which is not stretched, has excellent cuttability in all directions, has a suitable tear strength, and has excellent tearability.

[0007]

SUMMARY OF THE INVENTION The present invention provides 80 to 99.9 mol% ethylene and 1-99% ethylene in the presence of a metallocene catalyst.
The following properties (A-1) to (A-3) obtained by copolymerizing 0.1 to 20 mol% of butene and 0 to 10 mol% of an α-olefin having 3 to 12 carbon atoms (excluding 4 carbon atoms). (3) an ethylene / 1-butene copolymer of more than 90% by weight and 100% by weight and an olefin polymer in the range of 0 to less than 10% by weight. . Characteristics: (A-1) The density is 0.880 to 0.960 g / cm ³ . (A-2) The melt flow rate (MFR) at a load of 2.16 kg at 190 ° C. is 0.1 to 100 g / 10 minutes. (A-3) Melt tension (MT) at 190 ° C.
Is 0.85 g or less.

Preferably, the present invention is the tear strength (Y) in the tearing direction (MD) and the tear strength (X) in the direction (transverse direction) (TD) perpendicular to the pulling direction of the easily tearable film.
However, it is preferable to provide an easily tearable film of 10 N / mm to 70 N / mm.

In the present invention, the easily tearable film is preferably characterized in that the easily tearable film has a tensile elastic modulus of 100 to 350 MPa.

Preferably, in the present invention, the tear strength (Y) in the take-up direction (MD) is perpendicular to the take-up direction (transverse direction).
The value (Y / X) divided by the tear strength (X) of (TD) is
It is preferable to provide an easily tearable film characterized by being in the range of 0.4 to 1.

Preferably, the present invention is based on the above ethylene-1.
The butene copolymer further provides (A-4) an easily tearable film characterized in that the melt tension (MT) and the melt flow rate (MFR) satisfy the relationship represented by the following formula (1). Preferably.

[Equation 2]

[0012] Preferably, the present invention is based on the above ethylene.
It is preferable that the butene copolymer further provides (A-5) an easily tearable film characterized by having a molecular weight distribution (Mw / Mn) in the range of 3 to 7.

[0013] Preferably, the present invention is the above ethylene.
-It is preferable to provide an easily tearable film characterized in that the butene copolymer is a copolymer obtained by a continuous gas phase fluidized bed polymerization method.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The easily tearable film of the present invention is a composition containing or consisting of 55 to 100% by weight of an ethylene / 1-butene copolymer and 0 to 45% by weight of an olefin polymer, preferably ethylene. * 1-butene copolymer 60
~ 100 wt% and olefin polymer 0-40 wt%
A composition comprising or consisting of, more preferably, a composition comprising or consisting of 70 to 100% by weight of an ethylene / 1-butene copolymer and 0 to 30% by weight of an olefin polymer,
More preferably, ethylene / 1-butene copolymer 75-1
A composition containing or consisting of 100% by weight and 0 to 25% by weight of an olefin polymer, particularly preferably ethylene.
An easily tearable film produced from a composition containing or consisting of 80 to 100% by weight of a butene copolymer and 0 to 20% by weight of an olefin polymer. The easily tearable film of the present invention uses the resin component obtained from the ethylene / 1-butene copolymer alone and the composition of the ethylene / 1-butene copolymer and the olefin polymer in the above range,
It is possible to obtain a film which is excellent in film forming such as die forming and inflation forming, excellent in tearability in the take-up direction (MD) and in both the direction perpendicular to the take-up direction (TD), and excellent in cutability in all directions. The packaging bag obtained by bag making and tube processing using the film is used as a soft packaging material for food that requires easy opening, a packaging bag such as an envelope for direct mail, and a standing container used for refill containers for household detergents, etc. It can be applied to various packaging materials such as pouches.

Preferably, the easily tearable film of the present invention is
A composition containing or consisting of 55 to 100% by weight of an ethylene / 1-butene copolymer and 0 to 45% by weight of an olefin polymer, preferably an ethylene / 1-butene copolymer 6
A composition containing or consisting of 0 to 100% by weight and 0 to 40% by weight of an olefin polymer, more preferably 70 to 100% by weight of an ethylene / 1-butene copolymer and 0 to 30% by weight of an olefin polymer. A composition comprising or consisting of, more preferably ethylene / 1-butene copolymer 75
~ 100 wt% and olefin polymer 0-25 wt%
A composition comprising or consisting of ethylene, particularly preferably ethylene
An easily tearable film produced by inflation molding a composition containing or consisting of 80 to 100% by weight of a 1-butene copolymer and 0 to 20% by weight of an olefin polymer is preferable. The easily tearable film produced by inflation molding of the present invention is a resin obtained from an ethylene / 1-butene copolymer alone and a composition of an ethylene / 1-butene copolymer and an olefin polymer in the above range. Films with excellent blown formability, easy tearability in the take-up direction (MD) and both in the take-up direction and the perpendicular direction (TD), and excellent cutability in all directions, since appropriate melt tensions are obtained using the components Can be obtained. The packaging bag obtained by bag making and tube processing using the film is a soft packaging material for foods that requires easy opening,
It can be applied to various packaging materials such as packaging bags such as direct mail envelopes and standing pouches used in refill containers for household detergents.

Preferably, the easily tearable film of the present invention is
More than 90% by weight of ethylene / 1-butene copolymer 10
Compositions comprising or consisting of 0 wt% range and 0 to less than 10 wt% olefin polymer, preferably 93 to 100 wt% ethylene / 1-butene copolymer and olefin polymer. A composition comprising or consisting of 0 to 7% by weight, more preferably an ethylene / 1-butene copolymer in the range of 95% to 100% by weight and an olefinic polymer in the range of 0 to 5% by weight, or More preferably, a composition comprising or consisting of an ethylene / 1-butene copolymer in the range of 97% by weight to 100% by weight and an olefinic polymer in the range of 0 to 3% by weight, particularly preferably ethylene. A composition containing or consisting of 99% to 100% by weight of a 1-butene copolymer and 0 to 2% by weight of an olefin polymer is used for T-die molding. Easy splitting films produced Ri is preferred. The easily tearable film obtained by T-die molding uses a resin component obtained from the ethylene / 1-butene copolymer alone and the composition of the ethylene / 1-butene copolymer and the olefin polymer in the above range. Therefore, it is possible to obtain a film having excellent T-die high-speed moldability, excellent tearability in both the take-up direction (MD) and the direction perpendicular to the take-up direction (TD), and excellent cutability in all directions.
Further, in the case of the composition, a film having excellent transparency is obtained as compared with a single product, and a packaging bag obtained by bag-making or tube processing using the film is a soft packaging material for food that requires easy opening property, direct. The present invention can be applied to various packaging materials such as packaging bags such as mail envelopes and standing pouches used in refill containers for household detergents.

The ethylene / 1-butene copolymer is obtained by adding 80 to 99.9 mol% of ethylene, 0.1 to 20 mol% of 1-butene and 3 to 12 carbon atoms in the presence of a metallocene catalyst.
It can be obtained by copolymerizing 0 to 10 mol% of α-olefin (excluding carbon number 4), preferably 87 to 99.5 mol% of ethylene and 0.5 to 13 mol% of 1-butene and carbon. It is preferably obtained by copolymerizing with 0 to 5 mol% of α-olefin having a number of 3 to 12 (excluding the number of carbon atoms of 4),
More preferably, it is preferably obtained by copolymerizing 90 to 99 mol% of ethylene and 1 to 10 mol% of 1-butene with 0 to 3 mol% of an α-olefin having 3 to 12 carbon atoms (excluding 4 carbon atoms). , More preferably ethylene 91.5-
Α-olefin 0 having 98.8 mol% and 1-butene of 1.2 to 8.5 mol% and a carbon number of 3 to 12 (excluding the carbon number of 4)
Is preferably obtained by copolymerizing
It is particularly preferable to obtain it by copolymerizing 93 to 98 mol% of ethylene and 2 to 7 mol% of 1-butene and 0 to 2 mol% of α-olefin having 3 to 12 carbon atoms (excluding 4 carbon atoms). .

The ethylene / 1-butene copolymer is obtained by copolymerizing ethylene and 1-butene in the above-mentioned range with an α-olefin so that the ethylene / 1-butene copolymer can be easily drawn in the take-up direction (MD) and in both the take-up direction and the vertical direction (TD). Due to excellent tearability, it is possible to obtain a film having good cutability in all directions. The packaging bag obtained by bag making and tube processing using the film is used as a soft packaging material for food that requires easy opening, a packaging bag such as an envelope for direct mail, and a standing container used for refill containers for household detergents, etc. It can be applied to various packaging materials such as pouches.

The ethylene / 1-butene copolymer is an ethylene / 1-butene copolymer having the following characteristics (A-1) to (A-3). Characteristics: (A-1) Density is 0.880 to 0.960 g / cm ³ ,
It is preferably 0.895 to 0.950 g / cm ³ , more preferably 0.905 to 0.945 g / cm ³ , more preferably 0.910 to 0.945 g / cm ³ , and particularly preferably 0.915 to 0. Range of 940 g / cm ³ . (A-2) Melt flow rate (MFR) under load of 2.16 kg at 190 ° C. is 0.1 to 100 g / 10.
Min, preferably 0.5 to 50 g / 10 min, more preferably 0.7 to 30 g / 10 min, more preferably 1 to 10
g / 10 minutes, particularly preferably 1.5 to 8 g / 10 minutes. (A-3) Melt tension (MT) at 190 ° C.
Is 0.85 g or less, preferably 0.7 g or less, more preferably 0.6 g or less, particularly preferably 0.5 g or less, or the melt tension at 190 ° C. (M
T) is preferably in the range of 0.1 to 0.85 g, more preferably 0.15 to 0.8 g, and more preferably 0.2.
˜0.75 g, particularly preferably 0.2 to 0.6 g.

Density of ethylene / 1-butene copolymer (A
-1) is larger than the above range, the take-up direction (M
D), it is not preferable because the tear strength in both the pulling direction and the vertical direction (TD) becomes too small and the contents may spill when opened.
It is not preferable because the film is blocked or the film is stretched at the time of tearing, making it difficult to tear.

Melt flow rate (A-2) (MF) of the ethylene / 1-butene copolymer of the present invention at 190 ° C.
If R) is larger than the above range, the molding stability is poor, and if it is small, the load of a molding machine such as an extruder becomes large during molding, which is not preferable.

190 ° C. of ethylene / 1-butene copolymer
It is preferable that the melt tension (MT) (A-3) is in the above range because stable high-speed moldability can be obtained in T die molding.

Further, the relationship between the melt tension (MT) and the melt flow rate (MFR) (A-4) of the ethylene / 1-butene copolymer is preferably the formula (1), more preferably the formula (2). It is particularly preferable to satisfy the relationship represented by the formula (3).

[Equation 3]

[Equation 4]

[Equation 5]

190 ° C. of ethylene / 1-butene copolymer
Melt tension (A-3) (MT) and melt tension (MT) and melt flow rate (MF)
When the relational expression (A-4) of R) is out of the above range, T
High speed moldability in die molding is impaired and productivity is deteriorated, which is not preferable.

Further, the molecular weight distribution (Mw / Mn) (A-5) of the ethylene / 1-butene copolymer is preferably 3
To 7, more preferably 3.2 to 6.5,
The range of 3.5 to 6 is particularly preferable. Molecular weight distribution of ethylene / 1-butene copolymer (Mw
/ Mn) is less than the above range, the load of a molding machine such as an extruder is large at the time of molding, which is not preferable. When it is large, blocking resistance and heat sealability of the formed film are deteriorated. Not good for

Further, the melt flow rate (MFR _2.16 ) of the ethylene / 1-butene copolymer under a load of _2.16 kg at 190 ° C. and the melt flow rate (MFR _10.0 ) under a load of 10.0 kg at 190 ° C. Ratio of [(M
FR _10.0) / is _{(MFR 2. 16)] (A} -6), preferably 4 to 10, more preferably 4.5 to 8, more preferably 5-7, particularly preferably preferably 5 to 6 is .
190 ℃ of ethylene / 1-butene copolymer, 2.16k
Ratio of melt flow rate under g load (MFR _2.16 ) and melt flow rate under 190 kg load, 10.0 kg (MFR _10.0 ) [(MFR _10.0 ) / (MF
R _2.16 )] is less than the above range, the load of a molding machine such as an extruder becomes large at the time of molding, which is not preferable, and when it is large, blocking resistance and heat sealability of the formed film are poor. It is not preferable because it deteriorates.

The ethylene / 1-butene copolymer can be produced using a known metallocene catalyst by a known polymerization method such as a gas phase polymerization reaction or a liquid phase polymerization reaction. Preferably, the ethylene / 1-butene copolymer is a metallocene catalyst-containing solid component supplied to a gas phase fluidized bed reactor, and ethylene and 1-butene and an α-olefin having 3 to 12 carbon atoms (carbon An ethylene / 1-butene copolymer produced by a continuous gas-phase fluidized bed polymerization method is preferred.

As the metallocene catalyst, known metallocene catalysts can be used. The metallocene catalyst includes a combination of a metallocene compound of a transition metal of Group IV or V of the periodic table, an organoaluminum compound and / or an ionic compound, an organoaluminumoxy compound, and a ligand having a cyclopentadienyl skeleton. Periodic table No.
Known metallocene catalysts for olefin polymerization, such as group IV or group V transition metal compounds, can be used. As a transition metal of Group IV or V of the periodic table, titanium (T
i), zirconium (Zr), hafnium (Hf), vanadium (V) and the like are preferable.

The ethylene / 1-butene copolymer contains ethylene and 1-butene as essential components, and also has 4 carbon atoms such as propylene, pentene-1, 4-methylpentene-1, hexene-1, and octene-1. Excludes 3 to 1 carbon atoms
It can be obtained by copolymerizing a linear α-olefin of 2 or an α-olefin such as a cyclic α-olefin having 5 to 12 carbon atoms such as cyclopentene or cyclohexene or a mixture thereof with a metallocene catalyst.

Examples of the olefin polymer include ethylene / α-olefin copolymers produced by other metallocene catalysts other than the above ethylene / 1-butene copolymer, high-pressure low-density polyethylene, high-density polyethylene and the like. An ethylene resin mainly composed of ethylene can be used. As the ethylene-based resin, a copolymer of a monomer copolymerizable with ethylene such as an ethylene / vinyl acetate copolymer excluding α-olefin can be used.

In the easily tearable film of the present invention, lubricants such as higher fatty acids, higher fatty acid amides, metal soaps and glycerin esters, silicates such as natural silica, synthetic silica and synthetic aluminosilicates, glass beads, talc, diatomaceous earth and the like are used. -Based and acrylic polymer cross-linked products, organic anti-blocking agents such as silicon-based polymers, antioxidants such as phenol-based, phosphorus-based and sulfur-based, ultraviolet absorbers such as benzophenone, benzotriazole and HALS, aluminum hydroxide, Magnesium hydroxide, phosphorus-based, halogen-based flame retardants, silica, calcium carbonate,
Inorganic / organic fillers such as mica and carbon black, pigments such as azo type, phthalocyanine type, quinacridone type, iron oxide and ultramarine blue, antistatic agents, surfactants, nucleating agents and the like can be added.

As the higher fatty acid, a compound of a fatty acid and 2A such as magnesium and calcium of the periodic table, 2B such as zinc and 1A such as sodium, a fatty acid amide and the like can be used. C10 as higher fatty acid
A fatty acid derivative composed of ~ 20 can be used. As the fatty acid derivative having 10 to 20 carbon atoms, a fatty acid derivative such as pentadeca acid, hexadeca acid, palmitic acid, octadeca acid, stearic acid, nonadecanoic acid, icosaic acid, and oleic acid can be used. Particularly, calcium stearate and zinc stearate are preferable. As the higher fatty acid amide, oleic acid amide,
Stearic acid amide, erucic acid amide, behenic acid amide, ethylenebisoleic acid amide, ethylenebisstearic acid amide, ethylenebiserucic acid amide and the like can be used.

Particularly in the easily tearable film of the present invention,
The anti-blocking agent is preferably added in an amount of 0.01 to 100 parts by weight of the composition constituting the easily tearable film of the present invention.
˜2 parts by weight, more preferably 0.05 to 1 parts by weight, more preferably 0.1 to 0.8 parts by weight, particularly preferably 0.2 to 0.6 parts by weight. Particularly, in the easily tearable film of the present invention, the higher fatty acid amide and / or higher fatty acid is preferably 0.005 to 100 parts by weight of the composition constituting the easily tearable film of the present invention.
0.2 parts by weight, more preferably 0.008 to 0.15
It is preferable that the amount of the compound is 0.01 part by weight, more preferably 0.01 to 0.1 part by weight, and particularly preferably 0.02 to 0.08 part by weight.

In the composition for use in the easily tearable film of the present invention, there are no particular restrictions on the mixing method, mixing apparatus, and mixing equipment of each component, and there are known single-screw extruders (kneading machines),
Biaxial extruder (kneader) Tandem type kneading machine, calendar, Banbury mixer, kneading roll, brabender, which is a twin screw extruder and a single screw extruder (kneader) connected in series.
Devices such as plastograph and kneader can be used.

The easily tearable film of the present invention is a general film forming such as T-die forming such as single-layer T-die forming or multi-layer T-die forming including two or more layers, single-layer inflation forming or multi-layer inflation forming including two or more layers. Can be obtained by law.

The easily tearable film of the present invention preferably has a tear strength (Y) in the tearing direction (MD) and a tear strength (X) in a direction (transverse direction) (TD) perpendicular to the pulling direction. 70 N / mm range, more preferably 10-6
0 N / mm range, more preferably 10-50 N / mm
Range, particularly preferably in the range of 10-45 N / mm,
It is preferable because it can be stably and easily torn.

The easily tearable film of the present invention has a value (Y) obtained by dividing the tear strength (Y) in the take-up direction (MD) by the tear strength (X) in the direction (transverse direction) (TD) perpendicular to the take-off direction. /
X) is preferably in the range of 0.4 to 1, more preferably in the range of 0.45 to 1, and more preferably in the range of 0.5 to 1 easily tears in all directions regardless of the tearing direction. It is preferable because it can be obtained.

The easily tearable film of the present invention has a tensile modulus of preferably 100 to 350 MPa, more preferably 100 to 300 MPa, and particularly preferably 100 to 25.
An easily tearable film characterized by being 0 MPa is preferred.

The easily tearable film of the present invention is used as a single layer of the easily tearable film, a multilayer film in which two or more easily tearable films are laminated, or a laminate in which the easily tearable film and another film are laminated. I can. Other films mentioned above include nylon, polyester,
Stretched or unstretched plastic film such as polypropylene alone or coextrusion film with polyethylene, ethylene vinyl alcohol, etc., metal foil such as paper, aluminum, copper, etc., film made of metal or vapor deposited with inorganic or organic material It is possible to stack one or more layers of the above.

The easily tearable film of the present invention is a packaging film for a standing pouch which is often used in detergents, shampoos, rinses, foods, etc. when it is processed into a film for envelopes or the like when it is processed into a laminated body such as dry laminate. It can be used as a multilayer film that can be used as a material.

[0041]

EXAMPLES The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these examples. The characteristic values were measured as follows.

(A) Method for measuring properties of ethylene / 1-butene copolymer [1] Density: 190 ° C. according to JIS K7112
The strand obtained at the time of measuring the melt flow rate under a load of 2.16 Kg was heat-treated at 100 ° C. for 1 hour and gradually cooled to room temperature over 1 hour, and a sample was measured using a density gradient tube. [2] Melt flow rate (MFR _2.16 ): JIS
According to K7210, using a melt indexer,
It was determined by measuring the weight of the resin extruded in a strand shape at 190 ° C. under a load of 2.16 Kg for 10 minutes. [3] Melt flow rate ratio (MFR ₁₀ / MFR
_2.16 ): According to JIS K7210, using a melt indexer, the weight of the resin extruded in a strand shape at 10 ° C. under load of 10 kg at 190 ° C. for 10 minutes under load of 2.16 Kg at 190 ° C. It was determined by dividing by the weight of the resin extruded in the form of strands. [4] Molecular weight distribution: The molecular weight distribution (Mw / Mn) of the ethylene / 1-butene copolymer composition was measured by gel permeation chromatography (GPC). The measuring method is shown below. (4-1) Measuring device: WATERS 150CV was used. (4-2) Measurement sample: The temperature of the polymer was 145 ° C.
It was dissolved in a solvent (o-dichlorobenzene) at a concentration of 1 mg / ml. (4-3) Molecular weight distribution measurement: 0.4 ml of the measurement sample of the above (4-2) was injected into two GPC columns AT-806MS, solvent o-dichlorobenzene, temperature 145 ° C,
The flow rate was 1.0 ml / min. Measurement by GPC is 3
It went for 5 minutes. The polymer concentration in the solution separated by the GPC column was measured by a differential refractometer (RI). The molecular weight was converted by polystyrene standard. (4-4) Data processing: Data processing is VAX-STA
TION3100 was used. When a baseline is drawn on the GPC chromatogram obtained by the measurement in (4-3) above,
The area is integrated using the data processing software attached to the device, and the number average molecular weight (Mn), weight average molecular weight (Mw),
Mw / Mn is calculated automatically. The GPC chromatogram shows the size of the figure on the screen of the device, with the horizontal axis of 125 mm per 20 minutes of measurement time and the vertical axis of total integrated elution amount of 10
It was standardized to 0 and performed with 13 mm per 20. [5] Melt tension (MT): Capirograph 1C manufactured by Toyo Seiki Co., Ltd., temperature 190 ° C., diameter 2.09 mm
φ, length 8.03mm (tapered) orifice, when the resin is extruded at a speed of 10mm / min, the take-up speed is 20 through the pulley 490mm below the nozzle.
Tension (g) detected by a pulley while being collected at m / min [6] Comonomer concentration: The comonomer concentration was quantified by nuclear magnetic resonance spectrum (NMR). The measuring method is shown below. (6-1) Measuring device: JEOL JNM-EX400 was used. (Nuclide ¹³ C) (6-2) Measurement sample: Polymer at a concentration of 1 at 130 ° C.
O-dichlorobenzene (OD) at a ratio of 0% (g / ml)
It was dissolved in a mixed solution of CB) and deuterated benzene (C6D6) (ratio 4: 1). (6-3) NMR measurement: The sample of (6-2) above was sealed in a sample tube, and tetramethylsilane (TMS) was used as a standard, and the number of integrations was 1 at a frequency of 100 MHz (nuclide ¹³ C).
The measurement was performed 0000 times. (6-4) Data processing: Peak assignment of the obtained NMR chart was identified, and it was determined as the comonomer concentration (mol%) by the integrated intensity ratio of the carbon portion of the main chain skeleton and the peak (2 points) derived from the comonomer. .

Film Evaluation Method [1] Haze: Measured in accordance with JIS K7105 using a haze meter (NDH-1001DP manufactured by Nippon Denshoku Industries Co., Ltd.). [2] Gloss: Measured using a gloss meter (VG-1D manufactured by Nippon Denshoku Industries Co., Ltd.) according to JIS K7105. The gloss was measured in two directions, the outside and the inside, with respect to the winding of the film. [3] Tear strength: Tear strength is ASTM D192
The test piece shown in 2 was used to measure the Elemendorf tear strength under the conditions of a temperature of 23 ° C. and a humidity of 50%. The tear strength is a value obtained by tearing the film in the take-up direction (MD) during film forming and the width direction (T in the film forming time of the film).
D: The tear strength in two directions with the value of tearing at a right angle (vertical direction) to the pulling direction was measured. [4] Tear balance: Calculated by dividing the tear strength (MD) value measured in [3] by the width direction (TD) value.

[Examples 1 to 3 and Comparative Example 1] Resins having the physical properties shown in Table 1 were used. As polyethylene A1, polyethylene A2 and polyethylene B, those produced by a continuous gas phase fluidized bed polymerization method using a metallocene catalyst were used. Using the composition shown in Table 2 with the following three-layer T-die molding apparatus and molding conditions, a type 1 three-layer multilayer film having a thickness of 50 μm was produced, and haze, gloss, tear strength and tear balance were measured. The results are shown in Table 3. The 3-layer T-die forming device has L / D = 32, die: width 900 mm,
1.6 mm lip and feed block type extruder 3
Stand (middle layer: SHI Modern Machinery Main 65mm
φ, seal layer and laminating layer: satellite 40 mmφ), cooling roll: 450 mmφ, semi-mad roll, and an apparatus using an air chamber were used. The conditions for forming a multilayer film using a three-layer T-die forming apparatus are: set temperature: die part (220 ° C.), three-layer multilayer film thickness: 50 μm, cooling roll temperature: 40 ° C., surface treatment level: initial 42 dy
It was performed at ne / cm ² .

[0045]

[Table 1]

[0046]

[Table 2]

[0047]

[Table 3]

Examples 4 to 6 and Comparative Example 2 Resins having the physical properties shown in Table 4 were used. As polyethylene A3, polyethylene A4 and polyethylene D, those produced by a continuous gas phase fluidized bed polymerization method using a metallocene catalyst were used. A single layer film having a thickness of 150 μm was produced using the composition shown in Table 5 under the following single layer inflation molding apparatus and molding conditions, and haze, gloss, tear strength and tear balance were measured, and the results are shown in Table 6. Shown in. The single layer inflation molding apparatus is an extruder: L / D = 28,6
An apparatus manufactured by SHI Modern Machinery having a diameter of 5 mm, a die of 150 mm and a lip of 2.5 mm was used. Molding conditions for a monolayer film using a monolayer inflation molding apparatus are as follows: set temperature: die (180 ° C.), monolayer film thickness: 150 μm, surface treatment level: initial 42 dyn
e / cm ² .

[0049]

[Table 4]

[0050]

[Table 5]

[0051]

[Table 6]

[0052]

EFFECT OF THE INVENTION The easily tearable film of the present invention is excellent in film formability such as T-die molding and inflation molding, is excellent in cutability in all directions without stretching, and has a suitable tear strength. You can

Continued front page    F-term (reference) 4F071 AA15X AA16 AA18 AA21X                       AA28X AA81 AA82 AA88                       AF16Y AF30Y AF32Y AG28                       AG29 AH04 BB06 BC01 BC12                 4J002 BB032 BB051 BB052 BB062                       GG02                 4J100 AA02P AA04Q CA01 CA04                       DA04 DA09 DA11 DA42 DA49                       DA51 FA10 FA22 JA58

Claims (7)

[Claims] 1. Ethylene 80 in the presence of a metallocene catalyst.
~ 99.9 mol% and 1-butene 0.1-20 mol%
And the following characteristic (A) obtained by copolymerizing 0 to 10 mol% of an α-olefin having 3 to 12 carbon atoms (excluding 4 carbon atoms).
-1) to (A-3) ethylene / 1-butene copolymer 5
An easily tearable film composed of a composition containing 5 to 100% by weight and an olefin polymer of 0 to 45% by weight. Characteristics: (A-1) The density is 0.880 to 0.960 g / cm ³ . (A-2) The melt flow rate (MFR) at a load of 2.16 kg at 190 ° C. is 0.1 to 100 g / 10 minutes. (A-3) Melt tension (MT) at 190 ° C.
Is 0.85 g or less. 2. The tear strength (Y) in the tearing direction (MD) of the easily tearable film and the direction (transverse direction) perpendicular to the tearing direction.
The tear strength (X) of (TD) is 10 N / mm to 70 N /
mm, The easily tearable film according to claim 1. 3. The easily tearable film has a tensile modulus of 100.
It is -350 MPa, The easily tearable film of any one of Claim 1 or Claim 2 characterized by the above-mentioned. 4. A value (Y / X) obtained by dividing the tear strength (Y) in the tearing direction (MD) by the tear strength (X) in the direction (transverse direction) (TD) with respect to the pulling direction is 0. It is the range of 4-1 and the easily tearable film of any one of Claims 1-3 characterized by the above-mentioned. 5. The ethylene / 1-butene copolymer is further characterized in that (A-4) the melt tension (MT) and the melt flow rate (MFR) satisfy the relationship represented by the following formula (1). The easily tearable film according to any one of claims 1 to 4. [Equation 1] 6. The ethylene / 1-butene copolymer is further characterized in that (A-5) molecular weight distribution (Mw / Mn) is in the range of 3 to 7. The easily tearable film according to item 1. 7. An ethylene / 1-butene copolymer is a copolymer obtained by a continuous gas-phase fluidized bed polymerization method, which is easy to prepare according to any one of claims 1 to 6. Tearable film.