JP2001150614A - Polyolefinic laminated film for stretch packaging - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated film for stretch packaging. SOLUTION: A laminated film for stretch packaging is constituted by laminating a surface layer, which is based on an ethylene/vinyl acetate copolymer with a specific MFR and a vinyl acetate content of 5-25 weight % or a straight chain ethylene/α-olefin copolymer with a 4-8C α-olefin content of 5-25 weight % on at least the single surface of a base material layer based on a resin composition consisting of 60-40 weight % of a component (A), 25-45 weight % of a component (B) and 5-25 weight % of a component (C). The component (A) is a straight chain ethylene/α-olefin copolymer with a crystal fusing peak temperature of 100 deg.C or higher and the component (B) is selected from a soft polypropylene resin with specific mesopentad ratio (13CNMR) crystallization calorie and a specific MFR, having a crystalline block part and an amorphous block part in its molecular chain and controlled in stereoregularity and the component (C) is a petroleum resin, a cumarone/indene resin, a rosin resin or hydrogenated derivatives of them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film for stretch packaging of foods and the like, and in particular, has excellent appearance and elongation characteristics.
The present invention also relates to a laminated film for stretch packaging, which has an excellent balance of packaging suitability such as deformation recovery properties and bottom sealing properties.

[0002]

2. Description of the Related Art In recent years, foods such as fruits and vegetables, fresh fish, fresh meat, prepared foods and the like are directly or placed on a plastic tray and stretch-wrapped with a film. Instead of a conventional polyvinyl chloride film, a linear low-density polyethylene film (Japanese Patent Laid-Open Publication No. 64-14018) or a linear low-density polyethylene is used as an intermediate layer. And a three-layer laminated film (Japanese Patent Publication No. 2-18953, Japanese Unexamined Patent Publication No. 3-258542) and the like, and a stretch packaging film based on an ethylene-based resin have been put to practical use.

[0003] These ethylene-based resin stretch packaging films have a problem in deformation restoring property and bottom sealing property, which are properties of recovering without deforming wrinkles on the film surface when the package is transported or displayed at stores. There was no one that could fully satisfy the requirements of the market.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in stretch packaging films for foods and the like, and has as its object the object of the present invention is to provide appropriate slip, self-adhesiveness and anti-fog properties. It is an object of the present invention to provide a laminated film for stretch packaging, which is excellent in appearance, elongation properties, and excellent in balance of packaging suitability such as deformation restoring property and bottom sealing property.

[0005]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a base material layer obtained by mixing a general-purpose linear ethylene-α-olefin copolymer with a specific soft polypropylene resin and petroleum resin is used. The inventors have found that the above problem can be solved by a laminated film having the same, and have completed the present invention.

The gist of the present invention is that the following component (A) contains 60 to
A melt flow rate (MFR) (JIS) is provided on at least one surface of a base layer mainly composed of a resin composition comprising 40% by weight, a component (B) of 25 to 45% by weight and a component (C) of 5 to 25% by weight. K7210, 190 ° C, 2.16
kg load) is 0.2 to 5 g / 10 min, and the content of the ethylene-vinyl acetate copolymer having a vinyl acetate content of 5 to 25% by weight or the content of an α-olefin having 4 to 8 carbon atoms is 5 to 25% by weight. The present invention resides in a laminated film for a polyolefin-based stretch packaging, wherein a surface layer mainly composed of a linear ethylene-α-olefin copolymer is laminated.

(A) Linear ethylene-α having a crystal melting peak temperature of 100 ° C. or more as measured by a differential scanning calorimeter
-Olefin copolymer (B) Satisfies the following conditions (1) to (3) and has a controlled stereoregularity in which a crystalline block and an amorphous block portion are mixed in a molecular chain. Polypropylene resin (1) Mesopentad fraction (mmmm) determined from ¹³ C-NMR spectrum is 0.20 to 0.50. (2) After crystal melting at a heating rate of 10 ° C./min using a differential scanning calorimeter, 200 After heating to 200 ° C. and holding at 200 ° C. for 5 minutes, the heat of crystallization measured when cooling to room temperature at a cooling rate of 10 ° C./min is 5 to 30 J / g. (3) Melt flow rate (MFR) (JIS) K72
10, 230 ° C, 2.16 kg load) 0.4 to 40 g
/ 10 min (C) Petroleum resin, terpene resin, cumarone-indene resin, rosin resin, or hydrogenated derivative thereof

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The stretch packaging film of the present invention is a laminated film including at least two types of layers, a base layer and a surface layer. The base material layer is a layer mainly composed of a resin composition composed of the components (A), (B) and (C) described below. The component (A) has a crystal melting peak temperature measured by a differential scanning calorimeter of 100 ° C. or higher, preferably 110 ° C.
The above-mentioned linear ethylene-α-olefin copolymer. Here, if the crystal melting peak temperature is lower than 100 ° C., the heat resistance of the obtained film at the time of heat sealing becomes too low, and a hole may be formed in the film, which is not preferable. The α-olefin is not particularly limited, but may be C 4-8 butene-1, hexene-1,
4-methyl-pentene-1 and octene-1 are preferred,
These can be used alone or in combination of two or more. A specific example of such a linear ethylene-α-olefin copolymer having a crystal melting peak temperature of 100 ° C. or higher is an octene-1 content of 12% by weight.
There are the following linear ethylene-octene copolymers and the like, and a melt flow rate (MFR) (JIS K7210,
(90 ° C., 2.16 kg load) of 0.2 to 5 g / 10 min is suitably used.

A method for producing a linear ethylene-α-olefin copolymer applied to the present invention is a so-called Ziegler-Natta type catalyst obtained by ion-polymerizing ethylene and an α-olefin and using a transition metal compound as a catalyst. Or a so-called metallocene catalyst using an organometallic complex. Examples of the production process include a high-pressure method, a gas-phase method, a solution method, and a slurry method used in general polyolefin production.

The component (B) is used under the following conditions (1) to (5).
A soft polypropylene-based resin that satisfies (3) and has a controlled stereoregularity in which a crystalline block and an amorphous block portion are mixed in a molecular chain. A soft polypropylene resin in which a crystalline block and an amorphous block portion are mixed in the molecular chain has a characteristic that it generally has rubber elasticity, is soft and hard to be broken, and has good transparency. In addition, the object of the present invention is achieved by balancing the proportions of a crystalline block portion having an isotactic structure and a syndiotactic structure exhibiting rigidity and an amorphous block portion having an atactic structure exhibiting elastomeric properties. Suitable to achieve.

[0011] Here, that the crystalline block and the amorphous block portion are mixed in the molecular chain means that the crystalline block and the amorphous block portion exist in a random and / or block manner. And the chain length of each block portion may be arbitrary. In the present invention, it is preferable that the distribution is random in terms of transparency, appearance, and the like. Specifically, condition (1) is ¹³
Those having a mesopentad fraction (mmmm) of 0.20 to 0.50 determined from the C-NMR spectrum are used. Here, if mmmm is less than 0.20, the crystallinity is too low and the raw material pellets are easily blocked, and there is a practical problem in terms of handling properties. On the other hand, if it exceeds 0.50, the effect of lowering the crystallinity is not sufficient, which is not preferable.

The value of mmmm is calculated based on the measurement result of a ¹³ C-NMR (nuclear magnetic resonance) spectrum. That is, a ¹³ C-NMR spectrum was measured, and the difference in chemical shift due to the stereoregularity of the methyl group was 22.5.
Each splitting peak (m
(mmm-mrm). Here, the above mmmm (mesopentad fraction) means that the five methyl groups as side chains are located in the same direction with respect to the main chain formed by carbon-carbon bonds composed of any five consecutive propylene units. And rrrr (racemopentad fraction) is a carbon structure composed of any five consecutive propylene units.
It means a three-dimensional structure in which five methyl groups, which are side chains, are alternately located in opposite directions to a main chain formed by carbon bonds, or a ratio thereof. The assignment of the signal in the methyl group region is described in A. Zambelli et al (Macro
moleculars 8 , 687, (1975)).

As the above condition (2), after crystal melting using a differential scanning calorimeter at a heating rate of 10 ° C./min, the temperature is raised to 200 ° C., maintained at 200 ° C. for 5 minutes, and then cooled at a cooling rate of 10 ° C.
The heat of crystallization measured when cooling to room temperature at
Those having a range of ３０30 J / g are used. If the heat of crystallization is less than 5 J / g, the crystallinity is too low, and the raw material pellets are easily blocked, and there is a practical problem in terms of handling properties. On the other hand, if it exceeds 30 J / g, the effect of lowering the crystallinity with a small addition amount when mixed with the linear ethylene-α-olefin copolymer as the component (A) is insufficient, which is not preferable. Therefore, the preferable range of the heat of crystallization is 5 to 25 J / g.

Further, as a condition (3), a melt flow rate (MFR) (JIS K7210, 230 ° C., 2.1
6 kg load) 0.4 to 40 g / 10 min, preferably 0.1 to 0.4 g / 10 min.
The one in the range of 5 to 10 g / 10 minutes is used. If the melt flow rate is less than 0.4 g / 10 minutes, the viscosity of the polymer itself is too high to make extrusion molding difficult, and 40 g / 1
If the time exceeds 0 minutes, the viscosity of the polymer itself is too low, so that the film-forming stability is lost, or the strength of the film itself is insufficient, so that there is a practical problem.

The flexible polypropylene resin having a controlled stereoregularity in which a crystalline block and an amorphous block portion are mixed in a molecular chain applied to the present invention includes propylene and ethylene and / or A copolymer with an α-olefin having 4 or more carbon atoms is preferably used. Here, the content of ethylene and / or an α-olefin having 4 or more carbon atoms is preferably 25% by weight or less, and is preferably 2 to 15% by weight from the viewpoint of low-temperature characteristics and polymerization productivity, and more preferably 2 to 10% by weight. % Is particularly preferred. Further, in consideration of heat resistance at the time of heat sealing, those having a crystal melting peak temperature of 100 ° C. or higher, preferably 110 ° C. or higher are preferable. Further, as an α-olefin having 4 or more carbon atoms,
There is no particular limitation, butene having 4 to 8 carbon atoms.
1, hexene-1, 4-methyl-pentene-1 and octene-1 can be suitably used, and these can be used alone or in combination of two or more.

The component (B) can be used as a mixture of two or more kinds as long as it meets the object of the present invention. As a method for producing such a soft polypropylene-based resin, an inexpensive propylene monomer is used as a main component,
A method for efficiently and inexpensively polymerizing a flexible polypropylene resin with good moldability and controlled stereoregularity using various metallocene catalysts (single-site catalysts) and solid titanium catalysts has been proposed. The resin to be used is not particularly limited as long as it satisfies the gist of the present invention, but specific products include Huntsman.
An example is the product name “REXflex” of Polymer Corporation.

The component (C) includes petroleum resin, terpene resin,
Coumarone-indene resin, rosin resin, or hydrogenated derivatives thereof. Specifically, as the petroleum resin, there are an aromatic petroleum resin from alicyclic petroleum resins and C ₉ components from cyclopentadiene or dimer thereof, terpene resins and terpene from The terpene resin β- pinene Examples of the phenol resin include rosin resins such as gum rosin and wood rosin, and esterified rosin resins modified with glycerin or pentaerythritol. As the component (C), those having various glass transition temperatures mainly depending on the molecular weight can be obtained. However, the compatibility when mixed with the components (A) and (B),
Glass transition temperature is from 50 to 100 ° C, preferably from 70 to 90 ° C, from the viewpoint of bleeding property over time, color tone, thermal stability and the like.
The hydrogenated derivatives of are especially preferred.

Next, the base material layer is composed of 60 to 40% by weight of the linear ethylene-α-olefin copolymer as the component (A), and a soft polypropylene of controlled stereoregularity as the component (B). A petroleum resin, a terpene resin, a coumarone-indene resin, a rosin-based resin, or a hydrogenated derivative thereof, wherein the resin is 25 to 45% by weight and (C) component.
It is a layer mainly composed of a resin composition of about 25% by weight. Here, when the content of the component (A) is less than 40% by weight and the content of the component (B) exceeds 45% by weight, the crystallinity of the base material layer is excessively reduced, so that the rigidity (rigidity) of the film is increased.
And the problem is easy to occur in handling property and film cutting property. On the other hand, when the content of the component (A) exceeds 60% by weight and the content of the component (B) is less than 25% by weight,
The effect of improving deformation restoring property and bottom sealing property is insufficient, which is not preferable. Further, when the content of the component (C) is less than 5% by weight, the self-adhesiveness of the film is inferior and the bottom sealing property becomes insufficient, which is not preferable. On the other hand, if the content exceeds 25% by weight, problems such as a change in the strength of the film over time, or the bleeding of the petroleum resin on the surface, and the formation of a roll easily block the films.

In the film of the present invention, an ethylene-vinyl acetate copolymer (EVA) or a linear ethylene-α-olefin copolymer is laminated as a surface layer on at least one side, preferably both sides, of the substrate layer. As this EVA,
Vinyl acetate content of 5 to 25% by weight, preferably 10 to 2%
0% by weight, melt flow rate (MFR) (JIS K
7210, 190 ° C, 2.16 kg load) 0.2-5
g / 10 minutes is preferred. Here, if the vinyl acetate content is less than 5% by weight, the resulting film is hard, and the flexibility and elastic recovery are reduced, and the surface tackiness is not easily exhibited, which is not preferable. On the other hand, if it exceeds 25% by weight, the surface tackiness is too strong, and the unwinding property and appearance are liable to deteriorate.

The linear ethylene-α-olefin copolymer has an α-olefin content of 5 to 25% by weight, preferably 10 to 15% by weight, and an MFR (JIS K7).
210, 190 ° C, 2.16 kg load) 0.2-5g
/ 10 minutes is preferred. Here, when the α-olefin content is less than 5% by weight, the obtained film is hard, and it is difficult to obtain uniform extensibility at the time of stretch packaging, so that wrinkles are generated in the package and the package is easily crushed. Absent. On the other hand, if it exceeds 25% by weight, it is not preferable because film formation becomes difficult or unwinding property is lowered. Examples of the α-olefin include butene-1, hexene-1,4-methyl-pentene- having 4 to 8 carbon atoms.
1, octene-1 is preferred, and these can be used alone or in combination of two or more.

When the MFR of both EVA and the linear ethylene-α-olefin copolymer is less than 0.2 g / 10 minutes, the extrudability decreases, while when the MFR exceeds 5 g / 10 minutes, the film-forming stability decreases. It is not preferable because the thickness tends to decrease, and unevenness in thickness, a decrease in mechanical strength, and variations easily occur. In general, the entire thickness of the film of the present invention is in a range used for ordinary stretch packaging, that is, about 8 to 30 μm,
Typically, it is in a range of about 10 to 20 μm. The thickness of the base material layer is 0.3 to 0.9, preferably 0.4 to 0.8, relative to the total thickness, and specifically 5 to 20 μm.
m is preferable from the viewpoints of various properties and economy as a stretch film.

The film of the present invention can be obtained by melt-extruding a material from an extruder and forming it into a film by inflation molding or T-die molding. In the case of forming a laminated film, it is advantageous to co-extrude with a multilayer die. Practically, it is preferable to melt-extrude the material resin from the annular die to perform inflation molding, and the blow-up ratio (bubble diameter / die diameter) at that time is preferably 4 or more, and particularly preferably in the range of 5 to 7. . As a cooling method at that time, either a method of cooling from the outer surface of the tube or a method of cooling from both the outer and inner surfaces of the tube may be used.
Further, the film obtained here is heated to a temperature not higher than the crystallization temperature of the resin, and stretched 1.2 to 5 times in the machine direction of the film by utilizing the speed difference between the nip rolls, or 1. Biaxial stretching may be performed 2 to 5 times.

In the film of the present invention, the following various additives are appropriately added to the surface layer and / or the substrate layer in order to impart properties such as antifogging property, antistatic property, slipperiness and self-adhesiveness. can do. For example, an aliphatic alcohol having 1 to 12 carbon atoms, preferably 1 to 6 carbon atoms, and 10 to 2 carbon atoms.
2, preferably an aliphatic alcohol fatty acid ester which is a compound with 12 to 18 fatty acids, specifically, monoglycerin oleate, polyglycerin oleate, glycerin triricinoleate, glycerin acetyl ricinoleate, polyglycerin stearate, polyglycerol stearate, Glycerin laurate, methyl acetyl ricinolate, ethyl acetyl ricinolate, butyl acetyl ricinolate, propylene glycol oleate, propylene glycol laurate, pentaerythritol oleate, polyethylene glycol oleate, polypropylene glycol oleate,
Sorbitan oleate, sorbitan laurate, polyethylene glycol sorbitan oleate, polyethylene glycol sorbitan laurate, and the like, and polyalkylene ether polyols, specifically, polyethylene glycol, polypropylene glycol and the like, and further, a compound selected from paraffinic oils and the like At least one is based on 100 parts by weight of a resin component constituting each layer.
It is preferable to add 0.1 to 12 parts by weight, preferably 1 to 8 parts by weight.

[0024]

The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. In addition, various measured values and evaluations of the film displayed in this specification were performed as follows.

[0025] 1) using mesopentad rate (mmmm) JEOL Co., Ltd. of JNM-GSX-270 ⁽¹³ C- nuclear magnetic resonance frequency 67.8MHz), under the following conditions ¹³
The C-NMR spectrum was measured and calculated. Measurement mode: ¹ H-complete decoupling Pulse width: 8.6 microseconds Pulse repetition time: 30 seconds Total number of times: 7,200 times Solvent: mixed solvent of orthodichlorobenzene / deuterated benzene (80/20% by volume) Sample concentration: 100 mg / 1 ml solvent Measurement temperature: 130 ° C Here, the assignment of the signal in the methyl group region is described by A. Zamb
elli et al (Macromolecules
8 , 687, (1975)).

2) Glass transition temperature (Tg), crystal melting peak temperature (Tm) Using a Perkin Elmer DSC-7, a 10 m sample was prepared.
g was determined from a thermogram when the temperature was increased at a heating rate of 10 ° C./min according to JIS K7121.

3) Crystallization temperature (Tc), heat of crystallization (Δ
Hc) Using Perkin Elmer DSC-7, a sample of 10 m
g was melted at a heating rate of 10 ° C./min according to JIS K7121 and JIS K7122, and then heated to 200 ° C.
After holding at 200 ° C. for 5 minutes, it was determined from a thermogram when the temperature was lowered to room temperature at a cooling rate of 10 ° C./min.

4) Suitability for stretch packaging An automatic packaging machine (ISHIDA / WminMK-II manufactured by Ishida Koki Co., Ltd.) using a stretch film having a width of 350 mm.
Foam polystyrene tray (length 200mm, width 1)
(30 mm, height 30 mm) and the items shown in Table 2 were evaluated. Using the same film and tray, a hand wrapping machine (Diawrapper A-1 manufactured by Mitsubishi Plastics, Inc.)
05).

5) Temporal change The obtained wound film was stored in a constant temperature room at a temperature of 50 ° C. and a humidity of 60% for 10 days, and the surface state and the rewinding property were evaluated thereafter. ◎: There is no bleeding of the additive on the surface and no blocking between films. …: There is almost no bleeding of the additive on the surface, but there is a little blocking between the films. Δ: There is little bleeding of the additive on the surface, and peeling is slightly heavy due to blocking between films. ×: There is much bleeding of the additive on the surface, and the blocking between the films is so severe that it cannot be used practically.

Example 1 (A) Component Linear ethylene-α-olefin copolymer (I) (α-olefin: octene-1 content 4% by weight, Tm: 122.3 ° C., MFR: 2. (1 g / 10 min): 50% by weight (B) Component Soft polypropylene resin (II) with controlled stereoregularity (propylene content: 92.0% by weight, ethylene content: 8.0% by weight, mmmm: 0. 0%). 286, MFR: 3.0 g / 10 min, Tm: 115.7 ° C., Tg: −21.2 ° C., Tc: 69.7 ° C., ΔHc: 7.2 J / g, Huntsman Polymer Corporation, “REXflexWL209” ): 30% by weight (C) Component Hydrogenated derivative of cyclopentadiene-based petroleum resin (softening temperature 125 ° C, glass transition temperature 81 ° C): 20% by weight

The mixed resin composition composed of the above three components was used as a base material layer to a thickness of 10 μm, and on both sides thereof EVA (vinyl acetate content: 15% by weight, MFR at 190 ° C., 2.16 kg load = 2.0 g / 10 min) The surface layer of the composition obtained by melt-kneading 3.0 parts by weight of diglycerin monooleate as an anti-fogging agent in 100 parts by weight was adjusted to a circular three-layer die temperature of 190.degree. Extrusion inflation molding and a total thickness of 14 μm (2 μm / 10
μm / 2 μm).

(Example 2) In place of EVA used as the resin for the front and back layers in Example 1, linear ethylene-α was used.
Olefin copolymer (III) (α-olefin: octene-1 content 12% by weight, 190 ° C., MFR at 2.16 kg load = 1.0 g / 10 min, Tm = 102 ° C.,
"AFFINITY PL188" manufactured by Dow Chemical Company
0 "), except that a total thickness of 1
A film of 4 μm (2 μm / 10 μm / 2 μm) was obtained.

(Example 3) Soft polypropylene resin (III) having a controlled stereoregularity in place of the soft polypropylene resin (II) having a controlled stereoregularity used as the component (B) in Example 1 (Propylene content: 97.8% by weight, ethylene content: 2.2% by weight, mmmm: 0.42
2, MFR: 6.0 g / 10 min, Tm: 148.2 ° C.
Tg: -7.2 ° C, Tc: 89.4 ° C, ΔHc: 19.
8J / g, Huntsman Polymer Cor
(REXflexWL210)
Except that the total thickness was 14 μm in the same manner as in Example 1.
(2 μm / 10 μm / 2 μm) was obtained.

Example 4 Example 3 was repeated except that the mixing ratio of the three resins used in Example 1 was changed to 40% by weight of component (A), 40% by weight of component (B), and 20% by weight of component (C). Total thickness 14μm as in 1.
(2 μm / 10 μm / 2 μm) was obtained.

Comparative Example 1 A linear ethylene-α-olefin copolymer (V) was used in place of the linear ethylene-α-olefin copolymer (I) used as the component (A) in Example 1. (Α-olefin: octene-1 content 15% by weight, Tm: 94.3 ° C., MFR: 1.6 g / 10 min) except that a total thickness of 14 μm (2
μm / 10 μm / 2 μm).

Comparative Example 2 Example 3 was repeated except that the mixing ratio of the three resins used in Example 1 was changed to 30% by weight of component (A), 50% by weight of component (B), and 20% by weight of component (C). Total thickness 14μm as in 1.
(2 μm / 10 μm / 2 μm) was obtained.

(Comparative Example 3) The same as Example 1 except that the mixing ratio of the three resins used in Example 1 was changed to the following two (A) component 50% by weight and (B) component 50% by weight. Total thickness 14μm
(2 μm / 10 μm / 2 μm) was obtained. Comparative Example 4 The total thickness was 14 μm (2 μm / 10 μm / 2 μm) in the same manner as in Example 1 except that the mixing ratio of the three resins used in Example 1 was changed to 100% by weight of the component (A).
m) was obtained. Table 1 shows the evaluation of the suitability for stretch packaging and the like for Examples 1 to 3 and Comparative Examples 1 to 4.
It was shown to.

[0038]

[Table 1]

[0039]

[Table 2]

As can be seen from Tables 1 and 2, the laminated films of Examples 1 to 4 having the base layer having the three components specified by the present invention and the blending number thereof being within the range specified by the present invention were all obtained. It can be seen that the properties of the stretch film are well balanced. On the other hand, it can be seen that the laminated films of Comparative Examples 1 to 4 each having a different component or a base layer whose blending number is out of the range specified in the present invention are inferior in overall properties as a stretch film.

[0041]

According to the stretch film of the present invention, a better balance of packaging suitability such as deformation recovery property and bottom sealing property is obtained than that of a conventional stretch film for an ethylene resin stretch packaging. Cut / transport and wrapping can be performed without any problem.

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 4F100 AK02A AK07A AK62A AK62B AK62C AK63A AK68B AK68C AK80A AL05A BA02 BA03 BA06 BA10B BA10C GB15 JA05 JA06A JA06B JA06C JA11A JA12A JA20A JK00 JK3B01 YK00 JK00 YB00 BP00X BP02X CE003 FD100 FD200 GF00 GG02

Claims (4)

[Claims] (1) The following component (A) is 60 to 40% by weight,
Component (B) is 25 to 45% by weight and component (C) is 5-2.
A melt flow rate (MFR) (JI
SK7210, 190 ° C, 2.16 kg load).
An ethylene-vinyl acetate copolymer having a vinyl acetate content of 5 to 25% by weight or a carbon number of 4 to 5 g / 10 min.
8. A laminated film for polyolefin stretch packaging, comprising a surface layer mainly composed of a linear ethylene-α-olefin copolymer having an α-olefin content of 5 to 25% by weight. (A) a linear ethylene-α-olefin copolymer having a crystal melting peak temperature of 100 ° C. or higher as measured by a differential scanning calorimeter; (B) a molecular chain satisfying the following conditions (1) to (3): Soft polypropylene resin with controlled stereoregularity in which a crystalline block and an amorphous block part are mixed. (1) Mesopentad fraction (mmmm) determined from ¹³ C-NMR spectrum is 0.20 (2) After crystal melting using a differential scanning calorimeter at a heating rate of 10 ° C./min, the temperature is raised to 200 ° C., maintained at 200 ° C. for 5 minutes, and then cooled to room temperature at a cooling rate of 10 ° C./min. The heat of crystallization measured when the temperature is lowered is 5 to 30 J / g. (3) Melt flow rate (MFR) (JIS K72)
10, 230 ° C, 2.16 kg load) 0.4 to 40 g
/ 10 min (C) Petroleum resin, terpene resin, cumarone-indene resin, rosin resin, or hydrogenated derivative thereof 2. A linear ethylene-α-component as the component (A).
The olefin copolymer is a copolymer with at least one α-olefin selected from butene-1, hexene-1, 4-methyl-pentene-1, and octene-1 having 4 to 8 carbon atoms. The laminated film for a polyolefin-based stretch packaging according to claim 1, characterized in that: 3. A soft polypropylene resin having a controlled stereoregularity as the component (B), comprising 98 to 85% by weight of propylene and 2 to 15% by weight of ethylene and / or an α-olefin having 4 or more carbon atoms. 3. The laminated film for a polyolefin-based stretch packaging according to claim 1, which is a polymer and has a crystal melting peak temperature measured by a differential scanning calorimeter of 100 ° C. or higher. 4. The petroleum resin as the component (C) is a hydrogenated derivative and has a glass transition temperature of 50 to 100.
The laminated film for polyolefin stretch packaging according to claim 1, wherein the temperature is ℃.