JPH0948101A - Easily tearable laminated film, easily tearable bag, and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide an easily tearable laminated film, an easily tearable bag, and a method for producing the same, which have excellent easy tearability and linear cuttability and also have sufficient strength. SOLUTION: Ny6 and MXD6 are 40 to 85 parts by weight and 15 to 60 parts by weight, respectively (where Ny6 + MXD6 = 10 parts by weight).
0 parts by weight) and mixed to form a film, MD
The easily tearable film 18 is formed by stretching in the TD direction and the TD direction at a draw ratio of 2.8 times or more. This easily tearable film 18 and another film, the L-LDPE film 2
0 and 0 are laminated via an adhesive layer 30 having a dynamic elastic modulus E ′ at 25 ° C. of logE ′ ≧ 7.7, thereby having excellent easy tearability and linear cutability, and strength and barrier properties. The easily tearable laminated film 40 and the easily tearable bag 60 having improved functions are obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an easily tearable laminated film which can be easily torn, a method for producing the same, an easily tearable bag using the easily tearable laminated film, and a method for producing the same. It can be used as a packaging bag for products.

[0002]

BACKGROUND ART In recent years, films such as linear low-density polyethylene (L-LDPE) have been widely used as a seal base material (sealant) film for packaging bags for foods, medicines and the like. However, although this L-LDPE film is safe because of its excellent sealing strength, it has a large tear resistance, so that it cannot be cut straight along the cut line during use, and there is a problem during opening.

For example, (a) a laminated film having a uniaxially stretched film as an intermediate layer (Japanese Patent Publication Sho 58)
-38320, Japanese Examined Patent Publication No. 55-31725), (b) a structure in which the surface of the front substrate film is finely scratched for easy opening, and (c) an opening tape is attached to the opening of the film. There are such configurations.

[0004]

In the structure according to (a) described above, the number of intermediate layers is increased by one, and the material cost and the machining allowance for laminating become high. Further, although a uniaxially stretched film is interposed in the intermediate layer, this uniaxially stretched film does not contribute much in terms of strength. (B)
In the configuration according to (3), even if the front base material film is finely scratched and easily opened, the linear cut property is governed by the characteristics of the base material. In addition, since the surface is damaged even if it is fine, there is a concern about strength. In the configuration according to (c) above, the unsealing tape causes high cost and poor productivity.

An object of the present invention is to provide an easily tearable laminated film, an easily tearable bag and a method for producing them, which have excellent easy tearability and linear cuttability and also have sufficient strength.

[0006]

According to the present invention, nylon 6 (Ny6) and metaxylylene adipamide (MXD6) mixed in a predetermined mixing ratio are formed into a film and stretched under predetermined stretching conditions. An easily tearable laminated film is formed by obtaining an easily tearable film and laminating this easily tearable film with another film. At this time, in the present invention, based on the finding that the adhesive layer interposed between the easily tearable film and another film affects the easily tearable property of the easily tearable laminated film, the dynamic elasticity of this adhesive layer is determined. Control the rate (viscoelasticity). The present invention is intended to achieve the above object by these.

That is, Ny6 and MXD6 are mixed at a predetermined mixing ratio to form a film, and the film is stretched under predetermined stretching conditions to obtain an easily tearable film having excellent easy tearability and linear cutability. Can be formed. By laminating this easily tearable film with another film, an easily tearable laminated film having improved functions such as strength and barrier properties can be obtained.

On the other hand, even if the basic adhesive strength of the adhesive layer is sufficient, peeling due to deformation may occur during tearing. In this case, the other film does not follow the easily tearable film, and even if it is an easily tearable laminated film, good easy tearability cannot be obtained. This peeling depends on the dynamic modulus of the adhesive layer.

Therefore, by controlling the dynamic elastic modulus of the adhesive layer, peeling between the easily tearable film and the other film at the time of tearing is avoided, and the easily tearable film and the other film are smoothly torn. As a result, stable and good tearability can be secured.

Specifically, the easily tearable laminated film according to the present invention comprises 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (however, Ny6 + MXD6). = 100 parts by weight)
A single layer easily tearable film stretched at a magnification of 2.8 times or more in both the moving direction of the film (MD direction) and the width direction of the film (TD direction), and other single layer easily tearable film to be laminated. A film and an adhesive layer for laminating the single-layer easily tearable film to another film, and the dynamic elastic modulus E'at 25 ° C of the adhesive layer is logE'≥
It is characterized by being 7.7.

Alternatively, the easily tearable laminated film of the present invention comprises 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (where Ny6 + MXD6 = 100 parts by weight). ) Content, the film moving direction (MD direction) and the film width direction (TD
Direction), a multilayer easy-tear film including a layer of the easy-tear film stretched at a magnification of 2.8 times or more, another film bonded to this multilayer easy-tear film, a multilayer easy-tear film and another An adhesive layer to which the film is attached, and the dynamic elastic modulus E ′ at 25 ° C. of the adhesive layer is log
It is characterized in that E ′ ≧ 7.7.

The method for producing the easily tearable laminated film according to the present invention is 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (where Ny6 + MXD6 = 100). (Part by weight), and forms a single-layer easily tearable film stretched at a magnification of 2.8 times or more in both the moving direction (MD direction) of the film and the width direction (TD direction) of the film. Another film is attached to the flexible film via an adhesive layer, and the dynamic elastic modulus E'at 25 ° C is used as this adhesive layer.
It is characterized in that an adhesive having logE ′ ≧ 7.7 is used.

Alternatively, the method for producing an easily tearable laminated film of the present invention comprises 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts of metaxylylene adipamide (MXD6).
A multi-layer containing an easily tearable film layer containing a part by weight (however, Ny6 + MXD6 = 100 parts by weight) and stretched at a magnification of 2.8 times or more in both the film moving direction (MD direction) and the film width direction (TD direction). An easily tearable film is formed, and another film is attached to this multilayer easily tearable film via an adhesive layer.
It is characterized by using an adhesive having a dynamic elastic modulus E ′ at 0 ° C. of logE ′ ≧ 7.7.

The easily tearable bag according to the present invention is made of nylon 6 (N
y6) 40 to 85 parts by weight and metaxylylene adipamide (MXD6) 15 to 60 parts by weight (however, Ny6 + MXD6
= 100 parts by weight), and a single-layer easily tearable film stretched at a magnification of 2.8 times or more in both the moving direction (MD direction) and the width direction (TD direction) of the film, and the easy tearing of this single layer. Other film to be attached to the flexible film,
It is formed into a bag shape by an easily tearable laminated film having an adhesive layer for laminating the single layer easily tearable film and another film, and the dynamic elastic modulus E ′ at 25 ° C. of the adhesive layer is logE. It is characterized in that ′ ≧ 7.7.

Alternatively, the easily tearable bag of the present invention is made of nylon 6
(Ny6) 40 to 85 parts by weight and metaxylylene adipamide (MXD6) 15 to 60 parts by weight (however, Ny6 + MX
D6 = 100 parts by weight), and the moving direction of the film (MD
Direction) and the width direction (TD direction) of the film, and a multilayer easily tearable film including a layer of the easily tearable film stretched at a magnification of 2.8 times or more, and another film laminated to this multilayer easily tearable film. The bag is formed of an easily tearable laminated film having an adhesive layer for laminating the multilayer easily tearable film and another film, and the dynamic elastic modulus E'at 25 ° C of the adhesive layer is logE '. It is characterized in that ≧ 7.7.

The method for producing an easily tearable bag according to the present invention comprises 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6).
+ MXD6 = 100 parts by weight), both in the film moving direction (MD direction) and the film width direction (TD direction)
Form a single-layer easily tearable film stretched at a magnification of 2.8 times or more, and form an easily tearable laminated film by bonding other film to this single layer easily tearable film via an adhesive layer An adhesive having a dynamic elastic modulus E ′ at 25 ° C. of logE ′ ≧ 7.7 is used as the adhesive layer, and the easily tearable laminated film is formed into a bag shape.

Alternatively, the method of manufacturing the easily tearable bag of the present invention is as follows:
40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (however, N
y6 + MXD6 = 100 parts by weight), the film moving direction (MD direction) and the film width direction (TD direction)
A multi-layer easy-tear film including a layer of the easy-tear film stretched at a magnification of 2.8 times or more is formed together, and another film is attached to this multi-layer easy-tear film via an adhesive layer to facilitate easy tearing. Characterized in that a flexible laminate film is formed, an adhesive having a dynamic elastic modulus E ′ at 25 ° C. of logE ′ ≧ 7.7 is used as the adhesive layer, and the easily tearable laminated film is formed into a bag shape. To do.

The chemical formula of MXD6 is shown in Chemical Formula 1 below.

[0019]

Embedded image

Here, when the content of MXD6 is less than the above range, the easy tearing property and the linear cutting property are poor and it becomes difficult to cut by hand. On the other hand, when the content of MXD6 exceeds the above range, the impact strength is significantly reduced and the practicality becomes poor. The Ny6 content is preferably 60 to 80 parts by weight, and the MXD6 content is preferably 20 to 40 parts by weight.

The easily tearable film constituting the single-layer easily tearable film or the multilayer easily tearable film is prepared by melt-extruding a mixture of raw materials having the above-mentioned mixing ratio and then cooling the raw film in the MD direction. It can be manufactured by stretching at 2.8 times or more in both the TD and TD directions. Such stretching can be performed, for example, by simultaneous biaxial stretching by a tubular method or the like.

At this time, if the draw ratio is less than 2.8 times, the linear cut property becomes inferior, and the impact strength also decreases, causing a problem in practicality. The stretching ratio is preferably 3.0 or more in both MD and TD.

Necessary additives can be appropriately added to the easily tearable film constituting the single layer easily tearable film or the multilayer easily tearable film. Examples of such additives include anti-blocking agents (inorganic fillers and the like), water repellent materials (ethylene bisstearate ester agents and the like), and lubricants (calcium stearate and the like). Further, polyamide elastomer (PAE) or the like may be added to improve the strength.

The multi-layer easily tearable film is composed of a plurality of layers including at least one layer of the easily tearable film. Examples of the film forming a plurality of layers together with the layer of the easily tearable film include, for example, May be a layer having easy tearability, a layer made of the same material as the other film to be laminated (described later) can be used, and these layers may be used in combination. Further, in forming the multilayer easily tearable film, a plurality of layers may be simultaneously extruded and laminated by coextrusion. It should be noted that they may be laminated by laminating using an adhesive, and in this case, it is desirable to use the same adhesive layer as in the case of forming the easily tearable laminated film.

The easily tearable laminated film contains at least one of the above-mentioned single layer easily tearable film or multilayer easily tearable film, and may have any number of layers such as two layers and three layers, and other laminated layers. Various films can be used as the film.

However, when a sealant film is used as the other film, the sealant film is placed at a position adjacent to the single-layer easily tearable film or the multilayer easily tearable film and laminated with the above-mentioned adhesive layer. Is preferred. That is, by disposing the layer of the easily tearable film of the single layer or the easily tearable film included in the multilayer easily tearable film next to or relatively close to the sealant film, good easy tearability can be ensured. Like
For example, an easily tearable laminated film can be constructed by using various sealant films as the first layer, a single layer easily tearable film as the second layer, and various auxiliary base material films as the third layer.

As the other film, if it is a material of an auxiliary substrate film, for example, PET (polyethylene terephthalate), EVOH (saponified ethylene-vinyl acetate copolymer), PVA (polyvinyl alcohol), P
A biaxially or uniaxially stretched film such as P (polypropylene), PVDC (polyvinylidene chloride), HDPE (high density polyethylene), PS (polystyrene) or an unstretched film can be used. In addition, other than such a resin-based film, a metal film such as an aluminum foil may be used.

As an example of the other film, if it is a material of a sealant film, for example, L-LDPE is used.
(Linear low density polyethylene), LDPE (low density polyethylene), HDPE (high density polyethylene), EVA
(Ethylene-vinyl acetate copolymer), PB (polybutene-1), CPP (unstretched polypropylene), ionomer, PMMA (polymethylmethacrylate), and the like, and mixtures thereof can be used.

The laminating method of the easily tearable laminated film includes, for example, extrusion laminating, hot melt laminating, dry laminating and wet laminating.

Among these, in the easily tearable laminated film of the present invention, at least one surface of the single layer easily tearable film or the multilayer easily tearable film is formed by dry laminating or wet laminating using an adhesive layer. Laminate with film. For example, when the first layer and the third layer are other films and the second layer is a single-layer easily tearable film, a laminate of the first layer and the second layer and the second layer and the third layer is dried. It may be performed by a method using an adhesive such as a laminate. Alternatively, the first layer and the second layer may be adhered by a method such as extrusion lamination without using an adhesive, and the second layer and the third layer may be laminated by a method using an adhesive. When a single layer easily tearable film or a multilayer easily tearable film and another film are used to form a two layer easily tearable laminate film, they may be laminated by a method using an adhesive.

However, the dynamic elastic modulus E'after the adhesive layer is cured.
Is assumed to be logE ′ ≧ 7.7 at the usual 25 ° C., and preferably logE ′ ≧ 7.9. 25 of the adhesive layer
When the dynamic elastic modulus E ′ at 0 ° C. is less than the above range, delamination occurs at the time of tearing and other films are stretched, so that good tearability cannot be obtained. And
The dynamic elastic modulus E ′ at 25 ° C. may be log E ′ ≦ 9.0, but it may be more than that.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] A first embodiment of the present invention will be described below with reference to the drawings. Nylon 6 (Ny6) and metaxylylene adipamide (MXD6) 40 each
~ 85 parts by weight and 15-60 parts by weight (however, Ny6 + MXD
6 = 100 parts by weight) mixed in an extruder at 270
After melt-kneading at 0 ° C., the melt was extruded from a die having a diameter of 90 mm as a cylindrical film and then rapidly cooled with water to prepare a raw film 11.

Next, as shown in FIG. 1, the raw film 11 is inserted between a pair of nip rolls 12 and then heated by a heater 13 while gas is being pressed therein, and an air ring 14 is set at a stretching start point. MD by the tubular method by blowing more air 15 to expand the bubbles 16 and taking them with a pair of downstream nip rolls 17.
Direction and TD direction simultaneous biaxial stretching. The stretching ratio was 2.8 times or more. This stretched film 1
8 was placed in a tenter type heat treatment furnace and heat-fixed at 210 ° C. to obtain a single-layer easily tearable film 18.

Next, as shown in FIG. 2, the single-layer easily tearable film 18 and another film, the L-LDPE film 20, were dry laminated to obtain an easily tearable laminated film 40. Single layer easily tearable film 18 and LL
The adhesive layer 30 that is bonded to the DPE film 20 is
A material having a dynamic elastic modulus E ′ after curing at 25 ° C. of logE ′ ≧ 7.7 was used. Using these two easily tearable laminated films 40, an easily tearable bag 60 having a seal portion 61 was manufactured by heat-sealing the bottom and both sides with a bag making machine.

According to this embodiment as described above, the following effects are obtained. That is, 40 to 85 parts by weight and 15 to 60 parts by weight of Ny6 and MXD6 (however, Ny6
+ MXD6 = 100 parts by weight), and the original film 11 formed by mixing is formed in the MD direction and the TD direction, respectively.
By stretching at a magnification of 2.8 times or more, a single-layer easily tearable film 18 having sufficient easy tearability and linear cutability can be formed.

The easily tearable laminated film 40 including the single layer easily tearable film 18 as one layer makes the easily tearable bag 6
Since 0 is formed, the easily tearable bag 60 having excellent easy tearability and linear cuttability is obtained. The easily tearable laminated film 40 is L-LDPE which is a sealant film.
Since it is configured to include the film 20, the easily tearable bag 60 having excellent sealing strength and the like can be formed.

Then, the laminate of the single-layer easily tearable film 18 and the L-LDPE film 20 which is a sealant film has a dynamic elastic modulus E'lo after curing at 25 ° C. of lo.
Since it was performed through the adhesive layer 30 with gE ′ ≧ 7.7, an adhesive strength that can withstand tearing was obtained, and when tearing, L
The LDPE film 20 follows the single-layer easily tearable film 18 to exhibit stable and good tearability.

[Second Embodiment] FIG. 3 shows an easily tearable laminated film 50 according to a second embodiment. The easily tearable laminated film 50 is composed of the multilayer easily tearable film 19 and the L-LDPE film 20 which is a sealant film. Multi-layer easily tearable film 1
9 is the film 191, which is the first layer, and the film 19, which is the second layer.
2. The film 193 is the third layer. The films 191 and 193 of the first layer and the third layer are layers of easily tearable film in which Ny6 and MXD6 are mixed in a ratio of 40 to 85 parts by weight and 15 to 60 parts by weight (however, Ny6 + MXD6 = 100 parts by weight). , Second layer film 192
Is a layer of a film having a gas barrier property.

In producing the multi-layer easily tearable film 19, the raw materials of the films 191 to 193 of the first to third layers are mixed in predetermined proportions and melt-kneaded at 270 ° C. in three extruders. After that, the melt was laminated in three layers from a multilayer circular die having a diameter of 90 mm and extruded, followed by quenching with water to produce a cylindrical raw film. Next, in the same manner as in the first embodiment (single-layer easily tearable film 18) described above, stretching and heat setting were performed to obtain a multilayer easily tearable film 19.

The easily tearable laminated film 50 was formed by laminating the multilayer easily tearable film 19 and the L-LDPE film 20 by dry lamination. The adhesive layer 30 interposed between them had a dynamic elastic modulus E ′ after curing at 25 ° C. of logE ′ ≧ 7.7. Using these two easily tearable laminated films 50, an easily tearable bag 60 having a seal portion 61 was manufactured by heat-sealing the bottom and both sides with a bag making machine.

As described above, the easily tearable bag 60 made of the easily tearable laminated film 50 containing the multilayer easily tearable film 19 also has substantially the same action and effect as the case of using the easily tearable laminated film 40 described above. . That is, the layer 191 of the easily tearable film of the multilayer easily tearable film 19 and the L-LDPE film 20 which is the sealant film have a dynamic elastic modulus E ′ after curing at 25 ° C. of logE ′ ≧.
Since it was laminated with the adhesive layer 30 of 7.7, an adhesive strength that does not peel even when tearing was obtained, and at the time of tearing, the L-LDPE film 20 was a multi-layer easily tearable film 19.
Stable and good tearability is exhibited by following the above.

Further, here, the layer 19 of the second film is used.
Since the film having the gas barrier property is used for 2, the multilayer easily tearable film 19 and the easily tearable laminated film 50 having the gas barrier property are obtained, and the easily tearable bag 60 having excellent gas barrier property can be manufactured. If a film having a function other than the gas barrier property is used for the layer 192 of the second film, the easily tearable laminated film 50 and the easily tearable bag to which the function is added can be obtained.

[0043]

【Example】

[Example 1] The easily tearable bag of Example 1 is the easily tearable bag 6 made of the easily tearable laminated film 40 of the first embodiment.
It was manufactured based on 0. Ny6 and MXD6 constituting the single-layer easily tearable film are 80 parts by weight and 20 parts by weight, respectively.
The parts were mixed in parts by weight. The one used as Ny6 is Nylon 6 [UBE Nylon 1023 manufactured by Ube Industries, Ltd.].
FD (trade name), relative viscosity η _r = 3.6], and the one used as MXD6 was metaxylylene adipamide [MX Nylon 6007 (trade name), relative viscosity η _r = manufactured by Mitsubishi Gas Chemical Co., Inc. 2.7].

The magnification in simultaneous biaxial stretching is 3.0 times in both MD and TD, and the thickness of the single-layer easily tearable film after heat setting is 15 μm. Then, this single-layer easily tearable film is used as a surface base film, and also L-LDP.
E film [Unilux LS-722C (trade name), manufactured by Idemitsu Petrochemical Co., Ltd., thickness: 50 μm] was used as a sealant film, and both were dry laminated to obtain an easily tearable laminated film. This lamination was performed using an adhesive [Takelac A-615 (trade name), polyester type, log E '(25 ° C) = 7.9] manufactured by Takeda Pharmaceutical Co., Ltd. shown in Table 1. In addition, the main agent is shown on the left side of Table 1, and the curing agent is shown on the right side.
The mixing ratio of the main agent and the curing agent is as shown in the lower part of these figures. This easily tearable laminated film can be
An easily tearable bag was produced by making a bag of 0 mm × 150 mm.

[0045]

【table 1】

Here, the dynamic modulus of elasticity E'of the adhesive, the laminate peel strength of the easily tearable laminated film, and the tearability of the easily tearable bag were measured and evaluated. Table 1 shows the results. First, the dynamic elastic modulus E ′ of the adhesive used for lamination after curing was measured. After mixing the main agent of adhesive (Takelac A-615) and the curing agent (A-65), flow it onto a glass plate to form a thin film, cut a test piece from this thin film, and perform this test with a testing machine (Vibron). The piece was subjected to repeated vibrations to obtain the dynamic elastic modulus E ', and the measured value at a temperature of 25 ° C was used as a representative value.

Next, the laminating peel strength of the easily tearable laminated film was evaluated. That is, with respect to the easily tearable laminated film having a width of 15 mm, the laminate peel strength between the front substrate film (easily tearable film) and the sealant film (L-LDPE film) was measured by a tensile tester. When the measured value was 500 g / 15 mm width or more, it was evaluated as ◯, and when less than 500 g / 15 mm width, it was evaluated as x.

The tearability of the easily tearable bag was evaluated. The tearability was evaluated by the tearing state when the easily tearable bag was opened.
That is, when the surface base material film and the sealant film could be cut linearly without peeling at the time of tearing, ◯ was evaluated, and when peeling occurred, x was evaluated. In addition, Table 1
In the column of comprehensive evaluation of, ○ means good and × means bad.

[Examples 2 to 3] In the same manner as in Example 1,
An easily tearable laminated film and an easily tearable bag according to each example were obtained. However, the types of adhesives used for lamination were those shown in Table 1, respectively. That is, in Example 2, Toyo Morton's adhesive [Adcoat AD-590 (trade name)] was used, and in Example 3, Takeda Pharmaceutical Co., Ltd. adhesive [Takelac A-520 (trade name)] was used. The mixing ratio of the main agent and the curing agent is as shown in Table 1.

Example 4 The easily tearable bag of Example 4 was manufactured based on the easily tearable bag 60 made of the easily tearable laminated film 50 of the second embodiment. Ny6, MXD
6, the materials used such as L-LDPE film, the magnification at the time of simultaneous biaxial stretching, the type of adhesive used for lamination, the bag-making conditions, etc. were the same as in Example 1. However, the layers 191 and 19 of the first and third films of the multilayer easily tearable film 19
Ny6 and MXD6 constituting 3 were mixed in a proportion of 70 parts by weight and 30 parts by weight, respectively, and Ny6 and MXD6 constituting a layer 192 of the second film were mixed in a proportion of 20 parts by weight and 80 parts by weight, respectively. . The thickness of the multilayer easily tearable film after heat setting was set to 15 μm.

Comparative Examples 1 and 2 In the same manner as in Example 1,
An easily tearable laminated film and an easily tearable bag according to each comparative example were obtained. However, the types of adhesives used for lamination were those shown in Table 1. That is, in Comparative Example 1, an adhesive [Takelac A-975 manufactured by Takeda Pharmaceutical Co., Ltd.
(Trade name)], and in Comparative Example 2, an adhesive [Dick Dry LX-75 (trade name)] manufactured by Dainippon Ink and Chemicals, Inc. was used. The mixing ratio of the main agent and the curing agent is as shown in Table 1.

Also in the easily tearable laminated film and the easily tearable bag of these Examples and Comparative Examples, the dynamic elastic modulus E'at 25 ° C, the laminate peel strength and the tearability of the adhesive were the same as in Example 1. evaluated. Table 1 shows the results.

[Consideration of Examples and Comparative Examples] From Table 1,
It can be seen that the easily tearable laminated films according to all Examples and Comparative Examples have good laminate peel strength, and the basic adhesive strength is secured.

On the other hand, the easily tearable bags of Comparative Examples 1 and 2 had poor tearability. The dynamic modulus E'of the adhesive used in these laminates at 25 ° C is log
Since E '<7.7 and sufficient adhesive strength to withstand tearing was not obtained, it is considered that good tearability was not obtained.

[0055]

As described above, according to the present invention,
Ny6 and MXD6 are 40-85 parts by weight and 15-
60 parts by weight (however, Ny6 + MXD6 = 100 parts by weight) are mixed and formed into a film, which is MD direction and TD.
By stretching in the direction at a stretch ratio of 2.8 times or more, an easily tearable film having excellent easy tearability and linear cutability can be obtained. Then, by laminating a single-layer easily tearable film or a multilayer easily tearable film in which at least one layer is made of an easily tearable film, and another film, it is possible to improve functions such as strength and barrier properties. A tearable laminated film is obtained.

At this time, the adhesive layer for laminating the single-layer easily tearable film or the multilayer easily tearable film including the layer of the easily tearable film and the other film was used for dynamic elasticity at 25 ° C. after curing. By setting the rate E ′ to be logE ′ ≧ 7.7,
Prevents peeling during tearing and ensures stable and good tearability.

By constructing a bag with such an easily tearable laminated film, an easily tearable bag having excellent easy tearability, straight line cutting property and sufficient strength and having functions such as barrier property is provided. can get.

[Brief description of drawings]

FIG. 1 is a schematic view of a biaxial stretching device used in a method for manufacturing an easily tearable film according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing an easily tearable laminated film according to the embodiment.

FIG. 3 is a schematic view showing the easily tearable bag of the embodiment.

FIG. 4 is a configuration diagram showing an easily tearable laminated film according to another embodiment of the present invention.

[Explanation of symbols]

 11 original film 12,17 nip roll 16 bubble 18 single layer easily tearable film 19 multilayer easily tearable film 191,193 easily tearable film layer 20 other film L-LDPE film 30 adhesive layer 40,50 Easy tearing laminated film 60 Easy tearing bag

Claims (8)

[Claims] 1. Containing 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (however, Ny6 + MXD6 = 100 parts by weight),
A single layer easily tearable film stretched at a magnification of 2.8 times or more in both the moving direction of the film (MD direction) and the width direction of the film (TD direction), and other single layer easily tearable film to be laminated. A film and an adhesive layer for laminating the single-layer easily tearable film to another film, and the dynamic elastic modulus E'at 25 ° C of the adhesive layer is logE'≥
An easily tearable laminated film characterized by being 7.7. 2. Containing 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (however, Ny6 + MXD6 = 100 parts by weight),
A multilayer easily tearable film including a layer of the easily tearable film stretched at a magnification of 2.8 times or more in both the moving direction of the film (MD direction) and the width direction of the film (TD direction), and affixed to this multilayer easily tearable film. It has another film to be combined and an adhesive layer for laminating the multi-layer easily tearable film and the other film, and the dynamic elastic modulus E ′ of the adhesive layer at 25 ° C. is logE ′ ≧ 7.7. An easily tearable laminated film characterized by. 3. Containing 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (however, Ny6 + MXD6 = 100 parts by weight),
A single-layer easily tearable film stretched at a ratio of 2.8 times or more in both the film moving direction (MD direction) and the film width direction (TD direction) is formed, and the adhesive layer is formed on the single layer easily tearable film. While bonding other films through the adhesive layer, this adhesive layer has a dynamic elastic modulus E'at 25 ° C.
A method for producing an easily tearable laminated film, which comprises using an adhesive having logE ′ ≧ 7.7. 4. Containing 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (however, Ny6 + MXD6 = 100 parts by weight),
A multilayer easily tearable film including layers of the easily tearable film stretched at a magnification of 2.8 times or more in both the moving direction of the film (MD direction) and the width direction of the film (TD direction) is formed. An easily tearable laminated film, characterized in that another film is bonded to the above with an adhesive layer, and an adhesive having a dynamic elastic modulus E'at 25 ° C of logE'≥7.7 is used as the adhesive layer. Manufacturing method. 5. Containing 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (however, Ny6 + MXD6 = 100 parts by weight),
A single layer easily tearable film stretched at a magnification of 2.8 times or more in both the moving direction of the film (MD direction) and the width direction of the film (TD direction), and other single layer easily tearable film to be laminated. A dynamic elastic modulus E of the adhesive layer at 25 ° C. is formed in a bag shape by an easily tearable laminated film having a film and an adhesive layer for laminating the single layer easily tearable film and another film. An easily tearable bag characterized in that ′ is logE ′ ≧ 7.7. 6. Containing 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (however, Ny6 + MXD6 = 100 parts by weight),
A multilayer easily tearable film including a layer of the easily tearable film stretched at a magnification of 2.8 times or more in both the moving direction of the film (MD direction) and the width direction of the film (TD direction), and affixed to this multilayer easily tearable film. Another film to be combined, formed into a bag shape by an easily tearable laminated film having an adhesive layer for laminating the multilayer easily tearable film and another film, and the dynamic elasticity of the adhesive layer at 25 ° C. An easily tearable bag characterized in that the rate E ′ is logE ′ ≧ 7.7. 7. Nylon 6 (Ny6) 40 to 85 parts by weight and metaxylylene adipamide (MXD6) 15 to 60 parts by weight (however, Ny6 + MXD6 = 100 parts by weight),
A single-layer easily tearable film stretched at a ratio of 2.8 times or more in both the film moving direction (MD direction) and the film width direction (TD direction) is formed, and the adhesive layer is formed on the single layer easily tearable film. An easily tearable laminated film is formed by bonding other films through the adhesive layer. An adhesive having a dynamic elastic modulus E ′ at 25 ° C. of logE ′ ≧ 7.7 is used as the adhesive layer, and the easily tearable laminated film is used. A method for producing an easily tearable bag, which comprises forming the flexible laminate film into a bag shape. 8. Containing 40 to 85 parts by weight of nylon 6 (Ny6) and 15 to 60 parts by weight of metaxylylene adipamide (MXD6) (however, Ny6 + MXD6 = 100 parts by weight),
A multilayer easily tearable film including layers of the easily tearable film stretched at a magnification of 2.8 times or more in both the moving direction of the film (MD direction) and the width direction of the film (TD direction) is formed. An easily tearable laminated film is formed by laminating another film on the adhesive layer via an adhesive layer, and the dynamic elastic modulus E ′ at 25 ° C. is formed as the adhesive layer.
A method for producing an easily tearable bag, characterized in that an adhesive having logE '≧ 7.7 is used and the easily tearable laminated film is formed into a bag shape.