JP2003253064A - Stretch film for hand packaging and manufacturing process therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prepare a stretch film for hand packaging having an excellent extensibility hardly ruptured upon stretching, and a manufacturing process therefor. <P>SOLUTION: The stretch film for hand packaging contains at least one layer of a film formed from a resin composition containing 5-40 wt.% linear low- density polyethylene (A) having a density of 0.92-0.95 g/cm<SP>3</SP>, 45-65 wt.% linear low-density polyethylene (B) having a density of ≥0.85 g/cm<SP>3</SP>and <0.92 g/cm<SP>3</SP>, 15-30 wt.% low-density polyethylene (C) having a density of 0.91-0.93 g/cm<SP>3</SP>measured by a high pressure method and, against 100 pts.wt. total of (A), (B) and (C), 0.5-10 pts.wt. adhesive (D) and 0.5-5 pts.wt. antifogging agent. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hand stretch film and a method for producing the same. More specifically, the present invention relates to a stretch film for hand wrapping, which has excellent elongation properties and properties that are not easily torn when stretched, and which is suitable for hand wrapping such as notebook trays and odd-shaped trays, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, in supermarkets and the like,
A plastic film is used as a commercial packaging film for prepacking foods such as vegetables. This pre-packed film is a film for covering and wrapping foods that are subdivided and stored in plastic trays or the like, or foods that are still naked, and are transparent and have appropriate elongation elasticity and adhesiveness. It is required that the film be easily cut, the inside of the film should not fog when packaged, and that the heat sealing performance should be excellent.

Conventionally, as such a packaging film, a film made of a polyvinyl chloride polymer or an ethylene / vinyl acetate copolymer has been used. Of these, polyvinyl chloride films have excellent packaging suitability. However, due to recent environmental problems, a material containing no chlorine is required. In addition, ethylene / vinyl acetate copolymer film is expensive, so when used as a packaging material,
There are problems such as high packaging costs, odor problems, and easy rusting of packaging machine rolls. Under such circumstances, a polyolefin film is often used as a packaging material.

For example, Japanese Patent Application Laid-Open No. 11-228758 discloses an olefin stretch film using a high-pressure polyethylene and an ethylene / α-olefin copolymer resin. However, the film does not have sufficient elongation characteristics, and when used as a film for hand packaging, for example, there is a problem that the packaging operator is easily tired if the packaging is continued for a long time. Furthermore, the tackiness is not sufficient. In addition, there is a problem of film forming property that the width of the film discharged from the die during production of the film varies due to expansion and contraction. Further, conventionally, a polyolefin-based stretch film is often manufactured by an inflation molding method, but there is a problem that productivity is poor.

[0005]

In view of the above problems, the object of the present invention is to maintain transparency, adhesiveness, antifogging property and the like at the same level as conventional products, and to have excellent elongation characteristics, Moreover, it is an object of the present invention to provide a stretch film for hand wrapping which has a property of being difficult to tear when stretched, and a manufacturing method thereof.

[0006]

As a result of intensive studies, the present inventors have found that a mixed resin containing a specific amount of two types of linear low-density polyethylene and high-pressure low-density polyethylene having different densities is used as an adhesive and an anti-adhesive agent. Melting the resin composition with the addition of a clouding agent,
The present invention has been found out that a film containing at least one polyolefin-based film layer obtained by extruding and taking out under specific conditions meets the above-mentioned problems, and has reached the present invention.

That is, the present invention has a density of 0.92 to
5 to 40% by weight of linear low-density polyethylene (A) having a density of 0.95 g / cm ³ , and a linear low-density polyethylene (B) having a density of 0.85 g / cm ³ or more and less than 0.92 g / cm ³ (B ) 45-65% by weight, density 0.91-0.
93 g / cm ³ high pressure low density polyethylene (C)
15 to 30% by weight, 0.5 to 10 parts by weight of the adhesive (D), and 0.5 of the antifogging agent (E) to 100 parts by weight of the total amount of the above (A), (B) and (C). It is a stretch film for hand wrapping containing at least one layer formed from a resin composition containing 5 to 5 parts by weight.

In a preferred embodiment of the present invention, the component (A)
And the density difference of the component (B) is at least 0.015 g / cm
^The stretch film for hand wrapping which is ³ is mentioned. The characteristic of the stretch film for hand packaging according to the present invention is the ratio of the stress at 300% elongation (σ300) to the stress at 100% elongation (σ300) [(σ30
0) / (σ100)] is 1.1 to 1.6 in both the machine direction and the direction orthogonal thereto.

Further, another invention of the present invention is a method for producing the stretch film for hand packaging, wherein the resin composition is used in an amount of 200 to 270 by using an extruder with a T-die.
Kneading, melting and extruding at 40 ° C, draft ratio 40-
130, draft distance 50 to 120 mm, draw ratio 1.
It is a method for producing a stretch film for hand wrapping, which is taken under conditions of 1 to 1.3 times, cooled, and shaped.

The stretch film for hand packaging according to the present invention has the same level of transparency, adhesion, antifogging property, etc. as conventional products, and has excellent elongation properties and properties that are not easily torn during elongation. Specifically, the stress at 300% elongation (σ3) relative to the stress at 100% elongation (σ100) is
The ratio [(σ300) / (σ100)] of 00) is small both in the machine direction (hereinafter referred to as MD direction) and the direction orthogonal thereto (hereinafter referred to as TD direction), and is difficult to tear during extension. Therefore, when it is used as a stretch film for hand wrapping, the worker does not get tired even if he is engaged in the wrapping work for a long time, and the film does not break. Therefore, it is extremely useful as a stretch film for hand packaging.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The stretch film for hand packaging according to the present invention comprises a mixed resin of two kinds of linear low-density polyethylene (A and B) and high-pressure low-density polyethylene (C) having different densities, a pressure-sensitive adhesive (D) and a protective resin. A clouding agent (E) is added to form a polyolefin resin composition, and the obtained resin composition is kneaded, melted and extruded into a film by using an extrusion molding machine with a T-die, etc., under specific conditions. It is manufactured by picking it up at. The stretch film for hand packaging according to the present invention may be a single layer of a film formed from the above composition, or may be a laminate including at least one film layer formed from the above composition.

The two types of linear low-density polyethylene (A) and (B) used in the present invention have a crystallinity of about 0 to 50%, preferably 5 to 45%, more preferably X-ray diffraction. Is an ethylene / α-olefin copolymer having a content of 10 to 40%. Ethylene units as a main component, for example, 80 to 99 mol%, preferably 85 to 97 mol%, and more preferably 88 to 95 mol% are preferable.

The α-olefin copolymerizable with ethylene includes propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1
-Decene, 3-methyl-1-butene, 4-methyl-1-
Penten etc. are mentioned. The α-olefin as a comonomer is not limited to one type, but two or more types such as a terpolymer may be used.

The linear low-density polyethylenes (A) and (B) can be usually produced by copolymerizing ethylene and the above α-olefin in the gas phase or liquid phase in the presence of a transition metal catalyst. . For example, a Ziegler type catalyst, a Phillips type catalyst, a metallocene type catalyst and the like can be used. A metallocene-type catalyst is preferable in consideration of balance of sealing property at low temperature, strength, elastic modulus, elongation and the like. The polymerization method is not particularly limited, and the polymerization can be performed by a gas phase method, a solution method, a bulk polymerization method or the like.

The melt flow rate (hereinafter referred to as MFR) of the linear low-density polyethylene (A) and (B) used in the present invention.
In consideration of the low-temperature sealability, strength, elastic modulus, elongation property, etc. of the obtained film, the linear low-density polyethylene (A) has a MFR of 0.1 to 190 ° C. and a load of 2.16 kg of 0.1 to 0.1. 10 g / 10 minutes, density of 0.
92 to 0.95 g / cm ³ , linear low density polyethylene (B) has an MFR at 190 ° C and a load of 2.16 kg.
Is 0.1 to 10 g / 10 minutes, and the density is 0.85 g / cm ^3.
As described above, it is preferably less than 0.92 g / cm ³ .

The amount of the linear low-density polyethylene (A) and (B) in the molding resin composition affects the elastic modulus, elongation property, heat sealability and the like of the obtained film.
When the amount of the component (A) is too small, the elastic modulus is lowered, and further, the heat resistance is lowered and the heat sealable upper limit temperature is lowered. Also,
When the component (A) is too much, the elastic modulus becomes high, the elongation property deteriorates, and the heat-sealing start temperature becomes high. From this viewpoint, the proportion of the linear low-density polyethylene (A) in the molding resin composition is 5 to 40% by weight, and the proportion of the linear low-density polyethylene (B) is 45 to 65% by weight. Is preferred. The linear low-density polyethylenes (A) and (B) may be used as a mixture of two or more kinds of resins as long as the MFR and the density are within the above ranges.

Considering the range of the upper limit temperature from the heat sealing start temperature of the obtained film, that is, the so-called heat sealing property,
The density difference between the component (A) and the component (B) is at least 0.
It is preferably 015 g / cm ³ . Examples of commercially available products of (A) include those manufactured by Mitsui Chemicals, Inc., trade names: Evolution SP2540, SP3040, ULTOZEX 3530L, ULTOZEX 3021F, and the like (B).
Commercially available products of Mitsui Chemicals, Inc., trade names: Evolution SP0540, Tuffmer A4080, Tuffmer A
4085 and the like.

In the present invention, it is used as the component (C).
High pressure low density polyethylene (hereinafter referred to as HPLD)
Is a long-chain component produced by so-called high-pressure radical polymerization.
It is a low density polyethylene with many branches and many branches. density
Is 0.91 to 0.93 g / cm ³Is. Used in the present invention
High-pressure method low-density polyethylene (C) is used to form films
Properties, transparency of the resulting film, flexibility, elongation characteristics, etc.
Considering it, MF at 190 ℃, 2.16kg load
R is preferably 0.01 to 100 g / 10 minutes
Yes. More preferably, it is 0.05 to 10 g / 10 minutes.

This HPLD uses a swell ratio which represents the degree of long chain branching, that is, a capillary flow characteristic tester,
Internal diameter (D) 2.0 mm, length 15 m under the condition of 190 ℃
The ratio of the diameter (Ds) of the strand extruded from the nozzle of m at an extrusion speed of 10 mm / min and the inner diameter D of the nozzle (Ds /
It is preferable that D) is 1.3 or more. Further, the high-pressure low density polyethylene (C) is 50 mol% or less, preferably 30 mol% or less, more preferably 20 mol% or less of other α-olefin and vinyl acetate within a range not impairing the object of the present invention. It may be a copolymer with a polymerizable monomer such as acrylic acid ester.

The proportion of HPLD (C) in the resin composition depends on the moldability of the film, the transparency of the obtained film,
Affects flexibility etc. If the amount of HPLD (C) is too small, the moldability will decrease, and if it is too large, the transparency and flexibility will decrease. Considering this point, the amount of HPLD (C) in the resin composition is preferably in the range of 15 to 30% by weight. Commercially available products of HPLD (C) are, for example, Mitsui Chemicals Co., Ltd., trade names: Mirason F212, D12, D12.
1P, 16P and the like.

As the adhesive (D) used in the present invention, an aliphatic hydrocarbon resin, an aromatic hydrocarbon resin, an aliphatic
Aromatic Copolymer Hydrocarbon Resin, Dicyclopentadiene Hydrocarbon Resin, Hydrogenated Aliphatic Hydrocarbon Resin, Hydrogenated Aromatic Hydrocarbon Resin, Hydrogenated Aliphatic / Aromatic Copolymer Hydrocarbon Resin, Water Dicyclopentadiene hydrocarbon resin, synthetic terpene hydrocarbon resin, terpene hydrocarbon resin, hydrogenated terpene hydrocarbon resin, coumarone indene hydrocarbon resin, low molecular weight styrene resin, and rosin hydrocarbon resin Etc. These may be one type,
It may be a mixture of two or more kinds.

For example, a C4 fraction, a C5 fraction, a mixture thereof obtained by decomposing petroleum, naphtha, etc., or an arbitrary fraction thereof, for example, isoprene and 1,3-pentadiene in the C5 fraction are mainly contained. Aliphatic hydrocarbon resin as a raw material; aromatic hydrocarbon resin mainly containing styrene derivative and indene in C9 fraction obtained by decomposition of petroleum, naphtha, etc .; optional C4 fraction and C5 fraction Aliphatic / Aromatic Copolymerized Hydrocarbon Resin Copolymerized with C9 Fraction and C9 Fraction; Dimer Using Cyclopentadiene and the Like Contained in C5 Fraction Obtained by Decomposition of Petroleum, Naphtha, etc. as a Raw Material Dicyclopentadiene-based hydrocarbon resin obtained from as a main raw material; hydrogenated aliphatic hydrocarbon resin obtained by hydrogenating an aliphatic hydrocarbon resin; hydrogenated aromatic hydrocarbon resin Hydrogenated aromatic hydrocarbon resin; Hydrogenated aliphatic / aromatic copolymer hydrocarbon resin obtained by hydrogenating aliphatic / aromatic copolymer hydrocarbon resin; Hydrogenated dicyclopentadiene resin Hydrogenated dicyclopentadiene-based hydrocarbon resin obtained by the above; synthetic terpene-based hydrocarbon resin having a structure containing aliphatic, alicyclic and aromatic hydrocarbon resins; α, β-pinene in turpentine oil as a raw material Terpene-based hydrocarbon resin; Hydrogenated terpene-based hydrocarbon resin hydrogenated terpene-based hydrocarbon resin; Coumaron-indene-based hydrocarbon resin made from indene and styrenes in coal tar-based naphtha; Low-molecular-weight styrene-based resin Resin; examples include rosin-based hydrocarbon resins.

Commercially available aliphatic hydrocarbon resins include
For example, Maruzen Petrochemical Co., Ltd., trade name: Mascarets S-110A, Tonex Co., Ltd., trade name: Escoletz 1315 can be mentioned. Examples of commercially available aromatic hydrocarbon resins include Tosoh Corporation, trade name: Petcole 120, Mitsui Chemicals, Inc., trade name: Highlets. Examples of commercially available products of the aliphatic / aromatic copolymer hydrocarbon resin include Escorets 2307 and 213, manufactured by Tonex Co., Ltd.
Examples of commercially available dicyclopentadiene hydrocarbon resins include Marukarez M-525A and M-510 manufactured by Maruzen Petrochemical Co., Ltd.

Commercially available products of the hydrogenated aliphatic hydrocarbon resin include, for example, Masukalets H-505 manufactured by Maruzen Petrochemical Co., Ltd. Examples of commercially available hydrogenated aromatic hydrocarbon resins include Alcon P-125 and P-115, manufactured by Arakawa Chemical Co., Ltd.
Examples of commercially available hydrogenated aliphatic / aromatic copolymer hydrocarbon resins include Imerb P-125 and P-140 manufactured by Idemitsu Petrochemical Co., Ltd. As a commercial product of hydrogenated dicyclopentadiene hydrocarbon resin, manufactured by Tonex Co., Ltd., trade name: Escoletz 5320H
C and 228F. As a commercial product of the synthetic terpene-based hydrocarbon resin, Tonex Co., Ltd., trade name: Escoletz 1401 can be mentioned.

Commercially available terpene hydrocarbon resins include, for example, YShara Chemical Co., Ltd., trade name: YS
Resins PX-1250 and 1150 are mentioned. Examples of commercially available hydrogenated terpene hydrocarbon resins include Yasuhara Chemical Co., Ltd., trade name: CLEARON P-12.
5 and the same P-115. As commercial products of coumarone indene hydrocarbon resin, for example, Nippon Steel Chemical Co., Ltd.
Product name: Esclon V-120. Examples of the low molecular weight styrene-based resin include Sanyo Chemical Industry Co., Ltd., trade name: Hymer S. Examples of commercially available rosin hydrocarbon resins include Arakawa Chemical Co., Ltd.
Product name: Super Ester A-125, S-10
0 is mentioned.

Considering properties such as tackiness, adhesiveness, cuttability and impact strength of the resulting film, the amount of the tackifier (D) is the same as that of the linear low density polyethylene (A) and (B), and It is preferable to add 0.5 to 10 parts by weight to 100 parts by weight of the total amount of the high-pressure low-density polyethylene (C).

The antifogging agent (E) used in the present invention is a chemical compounded to prevent the moisture in the air from condensing and causing the surface of the film to fog. Therefore, there is no particular limitation as long as it has a function of making the surface of the film hydrophilic and spreading the generated water droplets, and those generally used as an antifogging agent can be used as they are.

A surfactant is used as such an antifogging agent. For example, sorbitan fatty acid esters such as sorbitan oleate, sorbitan laurate, sorbitan behenate, sorbitan stearate; glycerin fatty acid esters such as glycerin oleate, glycerin laurate, glycerin stearate; diglycerin oleate, diglycerin laurate, diglycerin. Behenate, triglycerin oleate, triglycerin laurate, triglycerin behenate, tetraglycerin oleate, tetraglycerin stearate, hexaglycerin laurate, hexaglycerin behenate, decaglycerin oleate, decaglycerin laurate, etc. Glycerin fatty acid ester; polyoxyalkylene ether such as polyoxyethylene lauryl ether; polyoxyethylene monolaurate etc. Kishiechiren fatty acid esters, alkyl amines such as lauryl diethanolamine; and alkyl alkanol amides such as lauric acid diethanol amide. It is not limited to these, and these may be used alone or as a mixture.

The antifogging agent (E) is used in an amount of 0.5 to 5 parts by weight based on 100 parts by weight of the linear low density polyethylene (A) and (B) and the high pressure low density polyethylene (C). Is compounded. When the compounding ratio of the antifogging agent is less than 0.5 part by weight, the antifogging effect is not obtained, and when it exceeds 5 parts by weight, the transparency of the film obtained due to the bleeding of the antifogging agent is obtained. Becomes worse. The antifogging agent is mixed in advance with either of the above-mentioned component (A) or (B), preferably a part of the component (B) to form a masterbatch, and this is mixed as the remaining component to prepare a resin composition. It is preferable to obtain the product.

The stretch film for hand packaging according to the present invention contains a weather resistance stabilizer, a heat resistance stabilizer, an antistatic agent, an anti-slip agent, an anti-blocking agent, a lubricant, a pigment, within the range not impairing the object of the present invention. Other additives such as a dye, a nucleating agent, a plasticizer, an antiaging agent, a hydrochloric acid absorbent, and an antioxidant may be blended as necessary.

The resin composition used for producing the stretch film for hand packaging according to the present invention can be produced by a known method. For example, the following 1) -4)
The manufacturing method is as follows. 1) Above (A)
(E) component, and other components optionally added,
A method of mechanically blending using an extruder or a kneader. 2) The components (A) to (E), and optionally other components, are added to a suitable good solvent (for example, a hydrocarbon solvent such as hexane, heptane, decane, cyclohexane, benzene, toluene and xylene). A method of dissolving and then removing the solvent. 3) A method in which the above-mentioned components (A) to (E) and optionally other components are separately dissolved in a suitable good solvent, and then mixed, and then the solvent is removed. 4) Above 1) to 3)
Method to combine the method of.

Of these, the method 1) is preferably used. Specifically, it can be carried out by heating, melting, and kneading using a kneader, a Banbury mixer, a kneader such as a roll, a single-screw or twin-screw extruder, and the like. Also, various resin pellets may be dry blended.

The stretch film for hand packaging according to the present invention comprises a resin composition containing the above components (A) to (E) and, if necessary, other components, for example, an extrusion molding machine equipped with a T die. Is produced by kneading, melting and molding into a film. Above component (A)
It may be formed only by (E) and a layer containing other components as required, or may be a laminate with another resin film layer. Examples of the resin forming the other resin film layer include polyolefin resins such as homopolymers and copolymers of ethylene, propylene, butene and the like. Further, a mixture of these polyolefin-based resins with what is called a selvage, which is a so-called ear, which is generated when a film containing the above components (A) to (E) is mixed, and the like are also included. To be

The total thickness of the stretch film for hand packaging according to the present invention is preferably about 5 to 50 μm in consideration of strength, handleability, cost and the like. More preferably about 8 to 30 μm, even more preferably 8 to 20 μm.
It is a degree. When laminated with another resin film layer, the thickness of each layer formed from the resin composition containing the above components (A) to (E) as an essential component and each layer formed from the other resin composition, respectively, The thickness is about 1 to 5 μm, and they are alternately laminated so that the total thickness of the film is within the above range. In that case, it is preferable to laminate so that the layer formed from the resin composition containing the above-mentioned components (A) to (E) as essential components serves as an outer layer. When the stretch film for hand packaging according to the present invention is a laminate, the thickness of the layer formed from the resin composition containing the above components (A) to (E) as essential components is at least 50 of the total thickness of the film. % Is preferable.

The stretch film for hand packaging according to the present invention is produced by an extrusion molding method using an extruder with a T-die, using the resin composition containing the above components (A) to (E) as essential components. Is preferred. In the T-die extrusion molding method, as the orientation prevention treatment, for example, a molding temperature of 200
~ 270 ° C, draft ratio (drawing ratio within draft distance)
40 to 130, draft distance (distance from die tip to contact of film with cooling roll) 50 to 120 mm, film temperature 40 to 70 ° C, draw ratio 1.1 to.
An extrusion molding method in which it is wound in 1.3 times and wound is preferably exemplified. After melt molding, the temperature for cooling and shaping is 15
It is preferably about -80 ° C. In the case of laminating with other film layers, the respective fills may be separately formed and then laminated with a laminator or the like, but a coextrusion method using a multilayer extrusion molding machine is preferable.

The stretch film for hand packaging according to the present invention formed as described above has good elongation characteristics and also has excellent strength during elongation. Specifically, it is 30 with respect to the stress at 100% elongation (σ100).
Ratio of stress (σ300) at 0% elongation [(σ300) /
(Σ100)] is 1.1 to 1.6. This stress ratio [([sigma] 300) / ([sigma] 100)] is in the range of 1.1 to 1.6 in both the MD and TD directions of the film, and is well balanced in the vertical and horizontal directions.

Usually, the stretch film for hand wrapping is manually carried out by a wrapping operator using a hand wrapper. For example, grasping the ends of the film placed on the payout roll with both hands, paying out a film of a length necessary to cover the entire tray on which the food is placed, and after covering the entire tray, cut the film with a heat wire, Next, the covered film is stretched in the TD direction, the films are overlapped with each other at the bottom of the tray, and then the combined part is heat-sealed to be packaged. When it is done manually, the film can be smoothly fed out, it is easy for the worker to unroll, it does not get tired even if it is wrapped for a long time, it does not break when stretched, it is difficult to peel off when stacking the films and it is easy to heat seal. Etc. performance is required. The stretch film for hand packaging according to the present invention has excellent elongation properties and excellent strength during elongation as described above. Further, it has appropriate adhesiveness and adhesion. Therefore, it is extremely useful as a stretch film for hand packaging.

[0038]

EXAMPLES The present invention will be described in more detail below with reference to examples. The evaluation of various characteristics according to the present invention was carried out by the following methods.

(1) Melt flow rate (MFR) (g
/ 10 minutes) Measured according to the method specified in ASTM D1238.

(2) Density (g / cm ³ ) It is measured by the method specified in ASTM D1505.

(3) Haze (%) The haze is measured by the method specified in ASTM D1003.

(4) 100% elongation stress (σ100, unit: MPa) and 300% elongation stress (σ300, unit: MPa) Instron type tensile tester [manufactured by Orientec Co., Ltd.,
Form: U-1330], and chuck distance: 50
mm, tensile speed: 500 mm / min, test piece shape: AST
The MD and TD directions are measured by MD638 type-1. From the obtained results, the ratio of the stress at 300% elongation to the stress at 100% elongation (σ300 / σ
100) is calculated.

(5) Packaging suitability A commercially available hand-type tray packaging machine adjusted by the maximum temperature of the central portion of the hot plate to be 115 ° C. [manufactured by ARC Co., Ltd., model:
Using a polywrapper, cabbage and cucumber were wrapped and taped as they were. 20 for expanded polystyrene round trays and fan trays
After packing with a weight of 0 g, the film was sealed by bringing it into contact with a heat-sealing hot plate of the handler top for 2 seconds. Each of the objects to be packaged was packaged in 100 pieces, and the number of wrinkles, the number of tears, and the number of normally packaged pieces were recorded. For round trays and fan trays,
The number of openings of the bottom film and the number of openings and the number of holes in the bottom film were recorded, and the number of openings of the bottom film was recorded.

Example 1 <Preparation of pressure-sensitive adhesive masterbatch> Ethylene / hexene-1 copolymer (B) produced using a metallocene type catalyst [Mitsui Chemicals, Inc., trade name: Evolue SP0
540, density 0.903 g / cm ³ , 190 ° C., MFR 3.8 g / 10 min at a load of 2.16 kg] 50% by weight, and hydrogenated aromatic hydrocarbon resin [Arakawa Chemical Industry Co., Ltd. ), Product name: Archon P12
5] A composition containing 50% by weight was kneaded and granulated at a resin temperature of 200 ° C. using a twin-screw extruder having a caliber of 30 mm and an L / D of 26 to obtain a masterbatch (MD).

<Preparation of Antifogging Masterbatch> Ethylene / hexene-1 produced using a metallocene type catalyst.
Copolymer (B) [Mitsui Chemicals, Inc., trade name: Evolution SP0540, density 0.903 g / cm ³ , 190
MFR 3.8g / 10 at ℃, load 2.16kg
Min] 90% by weight, and diglycerin oleate as an antifogging agent (E) [manufactured by Riken Vitamin Co., Ltd., trade name: O-71-
DE] A composition containing 10 wt% has a diameter of 30 mm, L / D
Kneading at a resin temperature of 200 ° C. using a twin-screw extruder of No. 26,
It was granulated and used as a masterbatch (ME).

<Preparation of Resin Composition> Ethylene / hexene-1 copolymer (A) produced using a metallocene type catalyst [manufactured by Mitsui Chemicals, Inc., trade name: Evolution SP2]
540, density 0.924 g / cm ³ , 190 ° C., MFR 3.8 g / 10 min at a load of 2.16 kg] 10 parts by weight, ethylene-hexene-1 copolymer (B) produced using a metallocene type catalyst [Mitsui Chemicals, Inc., trade name: Evolution SP0540, density 0.903 g / c
m ³ , 190 ° C., load 2.16 kg, MFR 3.
8 g / 10 min] 34.5 parts by weight, high-pressure low density polyethylene (C) [manufactured by Mitsui Chemicals, Inc., trade name: Mirason F-
212, density 0.924 g / cm ³ , 190 ° C., MFR 2.0 g / 10 min at a load of 2.16 kg] 28 parts by weight, the adhesive masterbatch (MD) 10 parts by weight,
And 25 parts by weight of the above antifogging agent masterbatch (ME) were blended to obtain a resin composition. (Composition of resin composition:
(A) 10% by weight, (B) 62% by weight, (C) 28% by weight, (D) 5 parts by weight, (E) per 100 parts by weight of the total amount of (A), (B) and (C). ) 2.5 parts by weight).

<Production of Film> Using the extruder with a T-die (die width: 65 mm, vacuum chamber system), the above resin composition was molded into a molding resin at a temperature of 250 ° C. and a resin temperature of 25.
0 ° C, die lip gap 0.78 mm, draft ratio 6
0, draft distance 80 mm, cast roll temperature 25
A monolayer film having a thickness of 13 μm was extruded and molded under the conditions of ℃, a draw ratio of 1.2 times, and a winding speed of 250 m / min to manufacture a stretch film for polyolefin-based hand packaging. Various properties of the obtained film were evaluated by the above methods. Table 1 shows main manufacturing conditions and evaluation results.

Examples 2 to 12, Comparative Examples 1 to 8 Example 1 except that the composition (compounding ratio) of the resin composition, the film thickness, and the molding conditions were changed as shown in Tables 1 to 5.
A polyolefin-based stretch film for hand packaging was manufactured in the same manner as in. Various properties of the obtained film were evaluated by the above methods. Main manufacturing conditions and evaluation results are shown in Tables 1 to 5.

[0049]

[Table 1]

[0050]

[Table 2]

[0051]

[Table 3]

[0052]

[Table 4]

[0053]

[Table 5]

[0054]

EFFECT OF THE INVENTION The stretch film for hand packaging according to the present invention has excellent elongation characteristics and resistance to tearing during elongation. Specifically, stress at 100% elongation (σ1
The ratio of stress (σ300) at 300% elongation to (00) [(σ300) / (σ100)] is MD direction and TD.
It is small in both directions and does not easily tear when stretched. Therefore, when used as a stretch film for hand wrapping, workers will not get tired even if they engage in wrapping work for a long time, and
There is no film tear. Therefore, it is extremely useful as a stretch film for hand packaging.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // (C08L 23/08 C08L 101: 00 101: 00) B29K 7:00 B29K 7:00 23:00 23 : 00 105: 16 105: 16 F-term (Reference) 4F071 AA18 AA19 AA21 AA39 AA69 AA82 AC06 AC10 AF15 AF21 AF56 BB06 BB08 4F210 AA07 AA08 AB01 AB09 AG01 AH54 AR06 AR12 QA10 QC02 QD15 QG01 QG18 BB05QBBQ05QBB15QW15 4J002 BAO4 EH046 EH056 EH156 EN106 FD206 FD344 GF00 GG02

Claims (6)

[Claims] 1. A linear low-density polyethylene (A) having a density of 0.92 to 0.95 g / cm ³ (A) 5 to 40% by weight,
Linear low-density polyethylene (B) having a density of 0.85 g / cm ³ or more and less than 0.92 g / cm ³ (B) 45 to 65% by weight, and a high pressure method having a density of 0.91 to 0.93 g / cm ^3. Low-density polyethylene (C) 15 to 30% by weight, adhesive (D) 0.5 to 10 parts by weight, and antifogging agent to 100 parts by weight of the total amount of the above (A), (B) and (C). (E) A stretch film for hand packaging, comprising at least one layer formed from a resin composition containing 0.5 to 5 parts by weight. 2. The stretch film for hand packaging according to claim 1, wherein the density difference between the component (A) and the component (B) is at least 0.015 g / cm ³ . 3. The hand packaging according to claim 1, wherein the linear low-density polyethylene as the component (A) and the component (B) is a copolymer produced by using a metallocene type catalyst. Stretch film. 4. A ratio [(σ30) of stress at 300% elongation (σ300) to stress at 100% elongation (σ100).
0) / (σ100)] is 1.1 to 1.6 in both the machine direction and the direction orthogonal to the machine direction, and the stretch film for hand packaging according to claim 1. 5. The stretch film for hand packaging according to claim 1, wherein the total thickness of the film is 5 to 50 μm. 6. The resin composition according to claim 1 is used in an amount of 200 to 27 by using an extruder with a T-die.
Knead and melt at 0 ° C, extrude, draft ratio 40
To 130, a draft distance of 50 to 120 mm, and a draw ratio of 1.1 to 1.3 times, and is drawn, cooled, and shaped to produce a stretch film for hand packaging.