JPH10128925A - Laminate film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a heat-seal film with a superior opening property, a heat- sealing property, transparency, and a sliding property. SOLUTION: The laminate film is formed with an intermediate layer laminated on at least one surface of a foundation material film, which consists of a specific resin layer of 10-100 pts.wt. ethylene-α-olefin random copolymer having 70-90mol.% content of a monomeric unit in terms of ethylene and 10-30mol.% content of a monomeric unit in terms of α-olefin except ethylene, and 10-100 pts.wt. polypropylene-α-alophine random copolymer having 80-99mol.% content of a monomeric unit in terms of propylene and 1-20mol.% content of a monomeric unit in terms of α-olefin except propylene. Furthermore, the surface of the intermediate layer is laminated with an exterior surface layer consisting of a propylene random copolymer having 85-99mol.% content of a monomer unit in terms of polyethylene and/or propylene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated film, and more particularly, to the peeling of a heat-sealed surface when a bag is made (hereinafter referred to as a "laminated")
(Referred to as openability).

[0002]

2. Description of the Related Art When packaging an article with a film, the film is heat-sealed. that time,
It is known to use a film in which a heat seal layer made of a polyolefin-based thermoplastic resin such as polypropylene or polyethylene is laminated on the surface of a base film.

[0003]

By the way, in such heat-sealing packaging, the joints between the films are
It is necessary to have sufficient strength so as not to be broken at the time of distribution, but at the same time, it is required to have the conflicting performance of being easily opened by hand.

[0004] Further, it is required that the joint can be peeled off cleanly when the package is opened. That is, in the laminated film, usually, when the bonding portion is to be peeled, stringing or fluffing is likely to occur. Then, smooth peeling does not occur at the weld interface between the films or inside the heat seal layer, and the base film is torn in the middle of opening without separating the bonded portion into the original films again.

[0005] Such a phenomenon leads to poor appearance of the article at the time of opening and lowers the commercial value. In addition, there is a danger that the torn portion becomes a starting point, the film is severely broken during opening, and the contents fall.

[0006] Under these circumstances, it has been desired to solve the above-mentioned disadvantages and to develop a heat-sealing film having excellent opening properties, heat-sealing properties, transparency and slipperiness.

[0007]

Means for Solving the Problems The present inventors have intensively studied to solve the above problems. As a result, it has been found that the above problem can be solved by using an intermediate layer made of a specific polyolefin resin layer and an outer surface layer made of polyethylene and / or a propylene-based random copolymer having a specific composition. Was completed.

That is, according to the present invention, there is provided a method comprising: (A) 50 to 85% by weight of an eluted component having an elution temperature of 20 ° C. or less by a temperature-increasing elution fractionation method, 5 to 30% by weight of eluted components and 1 eluted component at 70 ° C or higher
An intermediate layer consisting of a polyolefin resin layer of 0 to 40% by weight is laminated, and further, B) a polyethylene having a density of 0.91 to 0.95 g / cm ³ , and / or It is a laminated film in which an outer surface layer composed of a propylene-based random copolymer containing 85 to 99 mol% of a monomer unit based on propylene is laminated.

In the present invention, the polyolefin resin layer forming the intermediate layer is eluted to a specific elution component amount at each elution temperature in the measurement by the temperature rising elution fractionation method. As the polyolefin resin component forming such an intermediate layer, a polyolefin resin that satisfies the above-mentioned elution requirements may be used alone, but it is generally used by mixing and adjusting a plurality of polyolefin resins so as to satisfy the elution requirements. It is a target.

The polyolefin resin used is α
-Olefin homopolymers, random copolymers, block copolymers and the like. As the α-olefin, those having 3 to 12, preferably 3 to 8 carbon atoms such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene and 4-methyl-1-pentene are preferred. . Specific examples include homopolymers of the above-mentioned monomers, random copolymers containing ethylene or propylene as a main component, and block copolymers.

Among these polyolefin resins, resins containing a large amount of elution components having an elution temperature of 20 ° C. or lower include, for example, those having a monomer unit content of 40 to 90 based on ethylene.
Mol%, the content of monomer units based on propylene is 10 to
Ethylene-propylene random copolymer of 60 mol%; content of monomer units based on propylene is 40 to 70
Mol%, butene-based monomer unit is 30 to 60 mol%
And a propylene-butene random copolymer. These materials have a weight average molecular weight of preferably 30,000 to 350,000, and more preferably 50,000 to 300,000 in consideration of the opening property, heat sealing strength, and extrusion processability.

On the other hand, examples of the resin containing more than 20 ° C. and less than 70 ° C. or more than 70 ° C. or more include, for example, an α-olefin homopolymer; 99 mol%, α-
An ethylene-α-olefin random copolymer in which the monomer unit based on olefin is 1 to 20 mol%; the content of the monomer unit based on propylene is 80 to 99 mol%, Propylene-α-olefin random copolymers having a monomer unit content of 1 to 20 mol% are exemplified. In consideration of transparency and openability, these have a weight average molecular weight of preferably 50,000 to 500,000, preferably 100,000 to 350,000.

In the present invention, considering the amounts of the components of each of these resins at the respective elution temperatures, a plurality of resins may be mixed and adjusted so as to satisfy the elution requirements.

Here, the content of the elution component of the polyolefin resin layer at an elution temperature of 20 ° C. or lower is preferably from 60% by weight to 80% by weight. When the elution component having an elution temperature of 20 ° C. or lower is less than 50% by weight, the resulting laminated film is not preferable because the opening property of the laminated film is reduced. Elution temperature 20
If the amount of the eluted component at a temperature of not more than 85 ° C. is more than 85% by weight, it is not preferable because the opening property of the obtained laminated film decreases.

If the elution temperature is higher than 20 ° C. and lower than 70 ° C. and the content is less than 5% by weight, transparency is undesirably reduced. If the amount of this component is more than 30% by weight, unsealing properties of the obtained laminated film are undesirably reduced.

Further, the amount of the elution component having an elution temperature of 70 ° C. or more is particularly preferably 15% by weight to 30% by weight. If the elution component at an elution temperature of 70 ° C. or higher is less than 10% by weight, unsealing properties of the obtained laminated film are undesirably reduced. When the amount of this component is more than 40% by weight, unsealing properties and transparency of the obtained laminated film are unpreferably reduced.

The melt flow rate (hereinafter, abbreviated as MFR) of the polyolefin resin layer is set to 0.1 in consideration of film forming property.
1 to 50 g / 10 min, preferably 0.5 to 30 g / 10
Minutes are preferred.

In the present invention, among the specific resin compositions used as the polyolefin resin layer, those which can be most preferably used include: a) a monomer unit content of 70 to 90 mol% based on ethylene; 100 parts by weight of an ethylene-α-olefin random copolymer in which the monomer units based on α-olefins other than the above are 10 to 30 mol% b) The content of monomer units based on propylene is 80 to 99
Mol%, the content of monomer units based on α-olefins other than propylene is 1 to 20 mol%.
Examples of the olefin random copolymer include 10 to 100 parts by weight. When using these polyolefin resin compositions, when performing heat sealing, the intermediate layer is melted at a low temperature to form a heat sealing layer together with the outer surface layer, and has a good low-temperature heat sealing property. Become. In addition, the smoothness of the outer surface layer is also improved, and the slipperiness of the film becomes better. In addition, the film formability is improved.

The ethylene-α-olefin random copolymer has a monomer unit content of 70 to 9 based on ethylene.
0 mol%, preferably 73 to 87 mol%, and 10 to 30 mol%, preferably 13 to 27 mol% of monomer units based on α-olefins other than ethylene.
When the content of the monomer unit based on ethylene is less than 70 mol%, the slipperiness of the obtained laminated film tends to decrease. When the ethylene content is more than 90 mol%, the opening property of the obtained laminated film tends to decrease.

Other α-olefins include propylene, 1-butene, pentene, methylbutene, hexene,
Those having 3 to 12, preferably 3 to 8, carbon atoms such as methylpentene and octene are good. The melt flow rate is preferably from 0.1 to 50 g / 10 minutes, and more preferably from 0.5 to 30 g / 10 minutes, in consideration of the film forming property.

In the present invention, such ethylene-α-
The olefin random copolymer can be used by appropriately selecting from known ones having the above composition. Further, a polymer obtained by decomposing a polymerized random copolymer using a known compound such as an organic peroxide may be used.

On the other hand, the propylene-α-olefin random copolymer contains 8 units of propylene-based monomer units.
0 to 99 mol%, preferably 90 to 98 mol%, of a monomer unit based on an α-olefin other than propylene is 1 to 2
0 mol%, preferably 2 to 10 mol%. When the monomer unit based on propylene is less than 80 mol%, the opening property of the obtained laminated film tends to decrease. When this value is more than 99 mol%, transparency tends to decrease.

Other α-olefins include ethylene,
Those having 2 and 4 to 12, preferably 2 and 4 to 8 carbon atoms, such as 1-butene, pentene, methylbutene, hexene, methylpentene and octene, are good. The melt flow rate is from 0.1 to 50 g /
10 minutes, preferably 0.5 to 30 g / 10 minutes is suitable. The main peak in the differential scanning calorimetry (DSC) is 120 when considering the low-temperature heat sealability and the slipperiness.
It is good to be in the range of -150C, preferably 125-145C.

In the present invention, such propylene-α
The olefin random copolymer can be used by appropriately selecting from known ones having the above-mentioned composition. Further, a polymer obtained by decomposing a polymerized random copolymer using a known compound such as an organic peroxide may be used.

In the present invention, the ethylene-α-olefin random copolymer and the propylene-α-olefin random copolymer are propylene-α-olefin random copolymer with respect to 100 parts by weight of the ethylene-α-olefin random copolymer.
10 to 100 parts by weight, preferably 15 to 80 parts by weight, more preferably 15 to 5 parts by weight of the olefin random copolymer
It is preferable to mix 5 parts by weight. Thereby, the obtained polyolefin resin composition is usually adjusted so as to satisfy the elution requirement. Here, propylene-α-
When the blending amount of the olefin random copolymer is less than 10 parts by weight, the amount of the eluting component at 70 ° C. or higher by the temperature rising elution fractionation method of the polyolefin resin composition is too small, and the opening property of the obtained laminated film is reduced. It will be easier.
On the other hand, when the blending amount of the propylene-α-olefin random copolymer is more than 100 parts by weight, the amount of the eluted components by the temperature rise elution fractionation method of the polyolefin resin composition becomes too large, and the opening property of the obtained laminated film is increased. In addition, the transparency, particularly the opening property when the surface layer is stretched, tends to decrease.

The mixing of the ethylene-α-olefin random copolymer and the propylene-α-olefin random copolymer may be carried out by any method, but usually, the pellets of each copolymer are mixed with a mixer. After mixing the powders and / or pellets of the respective copolymers in a heated and molten state, it is preferable to carry out the mixing with an extrusion kneader.

Next, in the laminated film of the present invention, the base film on which the above-mentioned polyolefin resin layer is laminated on at least one side may be any resin film. Then, the main peak in DSC is 120 to 250 ° C., more preferably 1 to 250 ° C.
It is preferred to be made of a resin at 30 to 170 ° C. Specific examples include homopolymers or copolymers of olefins such as ethylene, propylene, butene, and methylpentene. Of these, polypropylene is particularly preferred. These resins that can be used as the base material layer may be used alone or in combination of two or more.

As the polypropylene used for the base film, a propylene homopolymer, 90 mol% or more of propylene and another α-olefin such as ethylene, 1-
Butene, 1-pentene, 1-hexene, 1-heptene,
A random copolymer or block copolymer with one or more of 10 mol% or less such as 4-methyl-1-pentene can be generally used. The MFR is preferably in the range of 0.5 to 20 g / 10 minutes in consideration of film forming properties. In the present invention, the base material film may be a multilayer film, for example, a multilayer film in which a collecting resin layer, a gas barrier layer such as silica vapor deposition, or the like is laminated on these polypropylene films as an intermediate layer. .

In the present invention, in the above laminated film, polyethylene having a density of 0.91 to 0.95 g / cm ³ is further provided on the surface of the polyolefin resin layer.
And / or 85 to 85 monomer units based on propylene.
An outer surface layer made of a propylene-based random copolymer containing 99 mol% is laminated. When the laminated film of the present invention is used as a heat seal film, this outer surface layer acts alone or melts together with the polyolefin resin layer to act as a heat seal layer. In addition, when this layer is located on the outer surface, the laminated film has further improved slipperiness. Furthermore, when the propylene-based random copolymer is used as the resin of the outer surface layer, the laminated film has excellent scratch resistance.

Here, the polyethylene needs to have a density of 0.91 to 0.95 g / cm ³ in consideration of the slipperiness, transparency, heat sealability and the like of the film. More preferably, it is 915 to 0.94 g / cm ³ . Also, considering film forming properties, etc.,
The melt flow rate (MFR) at 90 ° C. is 0.
It is preferably 1 to 20 g / 10 min, and more preferably 0.5 to 15 g / 10 min. In addition, such polyethylene is generally used for differential scanning calorimetry (D
Generally, the main peak in SC) is 115 to 130 ° C.

Specific examples of such polyethylene include ethylene homopolymers, ethylene-α-olefin copolymers, and mixtures thereof. Particularly, from the viewpoint of stretchability, a linear low-density polyethylene which is an ethylene-α-olefin copolymer is preferable. The ethylene content of the ethylene-α-olefin copolymer is preferably at least 87 mol%.

Here, the density of polyethylene is 0.91 g.
If it is less than / cm ³ , the film has insufficient slipperiness. On the other hand, when this density exceeds 0.95 g / cm ³ , the heat sealability and transparency of the film are reduced.

On the other hand, when the monomer unit based on propylene is 8
As the monomer other than the propylene-based monomer unit in the propylene-based random copolymer containing 8 to 99 mol%, a unit based on another known monomer copolymerizable with propylene can be employed without limitation. . Preferably, ethylene,
Α- having 2 and 4 to 12 carbon atoms such as butene, pentene, methylbutene, hexene, methylpentene and octene;
Olefin-based monomer units, which are represented by 1
Species or a combination of two or more species may be employed. As such a propylene-based random copolymer, specifically, a propylene-ethylene copolymer, a propylene-ethylene-butene terpolymer, a propylene-butene copolymer,
A propylene-hexene copolymer or a mixture thereof can be used.

Here, the content ratio of the monomer unit based on propylene in the propylene random copolymer is from 88 to 88%.
It needs to be 99 mol%, preferably 90-98 mol%. When the content of the propylene-based monomer unit is less than 88 mol%, the film has insufficient lubricating properties. On the other hand, when the content ratio of the monomer unit based on propylene exceeds 99 mol%, the heat sealability of the film is undesirably reduced. In consideration of film forming properties, the propylene random copolymer preferably has a melt flow rate at 230 ° C. of 0.1 to 20 g / 10 min, and more preferably 0.5 to 15 g / 10 min.
More preferably, it is minutes. Further, this propylene-based random copolymer has a main peak in differential scanning calorimetry (DSC) of 125 to 155 ° C., preferably 130 to 155 ° C.
It is good that it is in the range of -150 ° C.

The layer made of the above-mentioned polyethylene and / or propylene random copolymer may be provided as two or more layers.

In the present invention, the outer surface layer, the intermediate layer and the base film constituting the laminated film may contain, if necessary, an antistatic agent, an antifogging agent, an antiblocking agent, an antioxidant, a light stabilizer, Known additives such as a crystal nucleating agent, a lubricant, a surfactant for the purpose of imparting lubricity and imparting an anti-blocking property may be compounded and used.

Further, other resins can be mixed in the outer surface layer to such an extent that the physical properties of the present invention are not impaired. The resin to be mixed is not particularly limited, but, for example, a homopolymer or a copolymer of olefins such as propylene, ethylene, and butene, or a mixture of two or more of these is preferable. The addition amount is 20% by weight or less,
It is preferably at most 5% by weight. In particular, as another resin, a propylene-butene random copolymer having a butene content of more than 15 mol% and 30 mol% or less, and a propylene content of 10 to 10 mol%.
A 30 mol% butene-propylene random copolymer, an ethylene-α-olefin random copolymer having a density of 0.85 or more and less than 0.91 are preferable.

In the present invention, the thickness of the laminated film is not particularly limited.
m and preferably 15 to 120 μm. The thickness of the intermediate layer is generally 0.1 to 15 μm.
m is appropriately selected from the range of m, and preferably 0.5 to 10 μm. The thickness of the outer surface layer is preferably from 0.1 to 10 μm, more preferably from 0.5 to 5 μm, in consideration of slipperiness, film forming property, and the like.

The method of forming a laminated film is not particularly limited, and it may be manufactured by any method. Generally, the outer surface layer, the powder or pellets of the polyolefin resin component constituting the intermediate layer, is co-extruded with the resin component of the base film, quenched on a temperature-controlled chill roll and formed into a film without stretching, or further thereafter. A uniaxial or biaxial stretching method is preferred. It is also preferable that the resin component of the base film is melt-extruded and uniaxially stretched, and then the resin components of the intermediate layer and the outer surface layer are melt-extruded and stretched in a direction substantially perpendicular to the uniaxial stretching direction. As an example of longitudinal uniaxial stretching, generally pass the film between the low-speed roll at the forefront and the high-speed roll at the rear,
Stretching is performed according to the rotation speed ratio of both rolls. On the other hand, the transverse uniaxial stretching is preferably performed by a tenter method.
In addition, longitudinal and horizontal sequential biaxial stretching, simultaneous biaxial stretching, and the like can be performed by the methods described above. The stretching ratio is 5 to 60 in area ratio.
Double, more preferably 30 to 50 times.

Although the above is the case of the flat shape, in addition to this, it is also possible to perform longitudinal uniaxial, horizontal uniaxial, simultaneous biaxial stretching or the like on the tubular raw material by an inflation method. In this case, the raw material is heated to, for example, 80 to 150 ° C., and pressurized air is sent into the tubular film to form a film without stretching, or stretch uniaxially in the longitudinal or transverse direction, or simultaneously stretch in the longitudinal or transverse direction. What is necessary is just to carry out axial stretching.

In these molding methods, considering the transparency and elastic modulus (rigidity of the film) of the laminated film, 2
Axial stretching is preferred.

[0042]

Industrial Applicability The laminated film of the present invention is particularly suitable for a heat-sealing film, and is not only heat-sealed to form a structure having excellent sealing reliability, but also has an opening property, a low-temperature heat-sealing property, and a slip property. It will be excellent. In particular, when peeling off the fused joint, the two films are smoothly peeled off, and the tearing of either one of the base films is suppressed. Accordingly, the present invention is particularly effective when a biaxially stretched easily tearable substrate film is used.

In this laminated film, the intermediate layer and the outer surface layer have good transparency. Therefore, when a material having good transparency such as polypropylene is used as the material resin of the base film, a laminated film having excellent transparency can be obtained.

As the outer surface layer, polyethylene,
And / or a layer composed of a propylene-based random copolymer is laminated, so that it is further excellent in slip properties and scratch resistance.

[0045]

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 polyolefin resins used as the base film and the raw material of the laminated film in Examples and Comparative Examples are those shown in Table 1.

[0047]

[Table 1]

The measuring methods used in the following Examples and Comparative Examples were implemented by the following methods.

(1) Weight average molecular weight (Mw) Measured by GPC (gel permeation chromatography). SSC-7100 manufactured by Senshu Science Co., Ltd.
GPC apparatus uses O-dichlorobenzene as a solvent and
Performed at 45 ° C. The column is Showa Denko UT-807,
Two UT-806M and four UT-802.5 were connected in series and used. A calibration curve was prepared using standard polystyrene, and the weight average molecular weight was measured.

(2) Copolymer Composition Using a JNM-GSX-270 apparatus manufactured by JEOL Ltd.,
Ortho-dichlorobenzene / heavy benzene (volume ratio 90/1
Calculated from ¹³ C-NMR spectrum measured at 120 ° C. using 0) as a solvent.

(3) Melt flow rate (MFR) Measured according to JIS K7210.

(4) Measurement of elution temperature by temperature rise elution fractionation method (TREF) Automatic TREF device SSC-730 manufactured by Senshu-Kagaku Co., Ltd.
The measurement was performed under the following conditions using 0ATREF.

Solvent: ortho-dichlorobenzene Flow rate: 150 ml / hour Heating rate: 4 ° C./hour Detector: infrared detector Measurement wave number: 3.41 μm Column: “Packed column 30φ” manufactured by Senshu-Kagaku Co., Ltd. 30 mmφ × 300 mm Concentration: 1 g / 120 ml Injection amount: 100 ml In this case, the sample solution in the column was introduced at 145 ° C., and then cooled to 10 ° C. at a rate of 2 ° C./hour to adsorb the sample polymer on the surface of the filler. Thereafter, by raising the column temperature under the above conditions, the polymer eluted at each temperature was obtained.
The concentration was measured with an infrared detector.

(5) Measurement of main peak by DSC After weighing about 5 to 6 mg of a sample, the sample was sealed in an aluminum pan, and the temperature was increased from room temperature to 235 ° C. or 270 ° C. in a nitrogen flow of 20 ml / min by a differential calorimeter. Raise the temperature and at these temperatures
Hold for 0 minutes, then cool to room temperature at 10 ° C / min. Thereafter, the temperature of the main peak was measured by a melting curve obtained at a heating rate of 10 ° C./min.

(6) Transparency The haze value of the film was measured according to JIS-K6714.

(7) Low-temperature heat-sealing property (heat-sealing starting temperature)
Using a heat seal bar, set each temperature (from 80 ° C to 1
(Measured every 5 ° C up to 55 ° C)
A sample having a width of 15 mm was cut out from a sample sealed under the conditions of kg / cm ² and a heat sealing time of 1.0 second, and measured at a tensile speed of 500 mm / min using a tensile tester.
The results were average values of five samples. From the heat seal curve obtained by the above method, the heat seal strength was 300 g /
The temperature of 15 mm was set as the heat sealing start temperature.

(8) Slip property ASTM-D after film formation and curing at 40 ° C. for 2 days
It measured according to the dynamic friction coefficient measuring method of -1894.

(9) Openability Heat seal starting temperature and further 5 ° C. and 10 ° C.
For samples heat-sealed at high temperatures, 10
Each sample was measured using a tensile tester. Out of a total of 30 samples, the bond does not separate from the original films,
Judgment was made based on the number of pieces in which one of the base films was torn and separated. The criteria are as follows.

The measurement was carried out at a tensile speed of 500 mm / min and 1000 mm / min.

[0060]

[Table 2]

(10) Scratch resistance (scratch haze) In order to evaluate the easiness of scratching when the films are rubbed, two films were prepared, and one of the films (20 ×
30 cm) was fixed as the lower film. The other film is used as the upper film, and the diameter of the upper film is 10 cm.
The lower film was contacted by applying a load of 4.6 kg on the area of the circle, and the upper film was horizontally rubbed back and forth five times at intervals of 20 cm. The haze value before and after performing the above operation was measured, and it was evaluated that the smaller the haze value, the less likely it was to be damaged.
The criteria are as follows.

[0062]

[Table 3]

Examples 1 to 6 Using a resin shown in A in Table 1 as a substrate layer, a T-die extruder was used to extrude a sheet at 280 ° C. while heating and melting, and after cooling and solidifying on a chill roll, hot roll stretching. Depending on the machine 4.
It was stretched 5 times to obtain a uniaxially stretched sheet. Then, Table 1,
The resin of the intermediate layer and the outer surface layer shown in 4 was extruded into a sheet while being heated and melted at 280 ° C. using a T-die extruder, and the three-layer sheet was obtained by laminating the uniaxially stretched sheet and a roll on a roll. Subsequently, the film was stretched 9 times with a horizontal stretching machine. The thickness, haze, heat sealability, openability, slipperiness, and scratch resistance of the obtained film were measured, and the results are shown in Table 5.

The raw material resin constituting the outer surface layer includes:
0.5 parts by weight of spherical polymethyl methacrylate particles having an average particle diameter of 4 microns and 0.5 parts by weight of erucamide were added to 100 parts by weight of the raw material resin.

Example 7 A laminated film was obtained in exactly the same manner as in Example 1 except that the resin shown in B in Table 1 was used as the base material layer. The thickness, haze, heat sealability, openability, slipperiness, and scratch resistance of the obtained film were measured, and the results are shown in Table 5.

Example 8 The resin shown in A in Table 1 was used as a substrate layer, and the resin and the resin of the intermediate layer and the outer surface layer shown in Tables 1 and 4 were heated at 260 ° C. using a three-layer T-die extruder. To obtain a laminated film stretched 4 times vertically and 8 times horizontally by a tenter method biaxial stretching machine. The thickness, haze, heat sealability, openability, slipperiness, and scratch resistance of the obtained film were measured, and the results are shown in Table 5.

The raw material resin constituting the outer surface layer includes:
0.5 parts by weight of spherical polymethyl methacrylate particles having an average particle diameter of 4 microns and 0.5 parts by weight of erucamide were added to 100 parts by weight of the raw material resin.

Example 9 The resin shown in A in Table 1 was used as a base layer, and the resin and the resin of the intermediate layer and the outer surface layer shown in Tables 1 and 4 were heated at 260 ° C. using a three-layer T-die extruder. , And co-extruded under heating and melting, and cooled and solidified on a chill roll to obtain a three-layer film without stretching. The thickness, haze, heat sealability, openability, slipperiness, and scratch resistance of the obtained film were measured, and the results are shown in Table 5.

The raw material resin constituting the outer surface layer contains:
To 100 parts by weight of the raw material resin, 0.7 parts by weight of spherical polymethyl methacrylate particles having an average particle diameter of 4 microns and 0.5 parts by weight of erucamide were added.

Examples 10 to 13 A laminated film was obtained in exactly the same manner as in Example 1 except that the resins shown in Tables 1 and 4 were used as the resin for the intermediate layer. The thickness, haze, heat sealability, openability, slipperiness, and scratch resistance of the obtained film were measured, and the results are shown in Table 5.

Comparative Examples 1 to 10 Films were obtained in the same manner as in Example 1 except that the resins shown in Tables 1 and 4 were used as the intermediate layer and the outer surface layer. Thickness of the obtained film,
Haze, heat sealability, opening property, slip property, and scratch resistance were measured, and the results are shown in Table 5.

The raw material resin constituting the outer surface layer contains:
0.5 parts by weight of spherical polymethyl methacrylate particles having an average particle diameter of 4 microns and 0.5 parts by weight of erucamide were added to 100 parts by weight of the raw material resin.

[0073]

[Table 4]

[0074]

[Table 5]

Claims (2)

[Claims] 1. An at least one surface of a substrate film comprising: A) 50 to 85% by weight of an eluted component having an elution temperature of 20 ° C. or less by a temperature-increasing elution fractionation method, and 5 1 to 30% by weight and 70 ° C or higher
An intermediate layer consisting of a polyolefin resin layer of 0 to 40% by weight is laminated, and further, B) a polyethylene having a density of 0.91 to 0.95 g / cm ³ , and / or A laminated film formed by laminating an outer surface layer made of a propylene random copolymer containing 85 to 99 mol% of a monomer unit based on propylene. 2. The polyolefin resin layer of the intermediate layer comprises: a) a content of monomer units based on ethylene of 70 to 90 mol%, and a content of monomer units based on α-olefin other than ethylene of 10 to 30 mol%. A certain ethylene-α-olefin random copolymer 100 parts by weight b) the content of monomer units based on propylene is 80 to 99;
Mol%, the content of monomer units based on α-olefins other than propylene is 1 to 20 mol%.
The laminated film according to claim 1, comprising 10 to 100 parts by weight of the olefin random copolymer.