KR101342748B1 - Easy-split stretched film, easy-split laminated film, easy-split bag, and manufacturing method for easy-split stretched film - Google Patents

Abstract

The thermosetting stretched film comprises a virgin raw material composed of 60 to 85 parts by mass of Ny6 and 15 to 40 parts by mass of MXD6, and a thermal history article having a melting point of 233 to 238 ° C by melting and kneading Ny6 and MXD6. It consists of a raw material, and content of the said thermal history article is 5-40 mass% on the basis of the said raw material whole quantity.

Description

Process for producing thermosetting stretched film, thermosetting laminate film, thermosetting sack, and thermosetting stretched film

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram of the biaxial stretching apparatus used by the manufacturing method of the thermotropic stretched film which concerns on the 1st Embodiment of this invention.

2 is a cross-sectional view showing an example of a dither laminate film according to a second embodiment of the present invention.

3 is a cross-sectional view showing an example of a dither laminate film in the above embodiment.

4 is a cross-sectional view showing an example of a dither laminate film in the above embodiment.

It is a front view which shows the heat-storage bag in the said embodiment.

It is a figure which shows the evaluation method of the linear cutability which concerns on the Example of this invention.

Document 1: Japanese Patent Publication No. 58-38302

Document 2: Japanese Patent Application Laid-Open No. 5-220837

Document 3: Japanese Patent Application Laid-Open No. 5-200958

TECHNICAL FIELD This invention relates to a manufacturing method of a thermosetting stretched film, a thermosetting laminate film, a thermosetting bag, and a thermosetting stretched film.

In Japan, `` barrier-free '' of eliminating barriers in various fields to affect the situation of aging society, so that elderly people and people with disabilities can spend a comfortable social life with young people and healthy people. The concept is starting to get the spotlight.

On the other hand, films, such as linear low-density polyethylene (L-LDPE), are used abundantly as a seal base material (sealant) film of packaging bags, such as a foodstuff and a chemical | medical agent. However, this L-LDPE film is safe because of its excellent seal strength, but has a problem that it is difficult to open it without being cut straight along the cut surface at the time of use because of its high tear resistance.

Therefore, the request for "barrier-free" is also very high also in the field of packaging, and specifically, the demand for the openability (heating property) is increased further with respect to various food packaging materials and medical packaging materials.

Thus, various proposals have been made for imparting heat resistance, in particular, linear cutability, to the film constituting the bag.

For example, the structure (document 1) which used the laminated film which has a uniaxial stretched film as an intermediate | middle layer, and nylon 6 (henceforth Ny6) and metaxylylene adipamide (henceforth MXD6) as a notation film. The example using the biaxially stretched film which consists of blended resin of the is known (document 2, document 3).

In the structure concerning literature 1, although the uniaxially stretched film is interposed in the intermediate | middle layer, although it is excellent in linear cut property, this monoaxially stretched film does not contribute very much in terms of strength.

On the other hand, in the structure concerning literature 2 or 3, even if it provided the notation material excellent in linear cut property, and even if it was set as a laminated film, since the outstanding linear cut property can be maintained, it is high in practical value as a thermosetting bag. However, when the biaxially oriented film made of the blended resin of Ny6 and MXD6 is placed under severe conditions after forming the laminate film, there is a fear of causing so-called intralayer peeling in the layer of the biaxially oriented film. When such intralayer peeling occurs, the strength of the laminate film becomes unstable, and a practical problem occurs when a bag is formed.

Therefore, the main object of the present invention is to produce a ditherable stretched film having excellent linear cutability and not causing in-layer peeling in the stretched film layer, a thermosetting laminate film using the same, a thermosetting bag, and a thermosetting stretched film. To provide a method.

The thermosetting stretched film of the present invention is 60 to 85 parts by mass of nylon 6 (hereinafter also referred to as Ny6) and 15 to 40 parts by mass of metaxylyleneadipamide (hereinafter also referred to as MXD6) (the sum of the quantum is 100 parts by mass). ) As a raw material, wherein the tearing strength in the MD direction (moving direction of the film) and / or TD direction (width direction of the film) of the heat-stretching stretched film is 70 N / cm or less, and the heat resistance When the aging film and the laminated film formed by laminating a linear low-density polyethylene film are aged at 40 ° C. for 3 days and then subjected to an interlaminar peeling test, intralayer peeling does not occur inside the heat-stretched stretched film. It is characterized by not.

According to the thermosetting stretched film of this invention, since Ny6 is 60-85 mass parts and MXD6 is 15-40 mass parts as a compounding ratio of a raw material, by extending | stretching an unstretched raw film in MD direction and / or TD direction, The tearing strength of the same direction is 70 N / cm or less, and the thermosetting stretched film excellent in linear cut property is obtained. Moreover, when biaxially stretching an unstretched raw film, it can also be a heat-stretched stretched film excellent also in impact resistance.

Moreover, when the aging film is laminated | stacked for 3 days at 40 degreeC about the laminated | multilayer film formed by laminating | stacking the heat-stretched stretched film of this invention and a linear low density polyethylene film, the heat-stretched stretched film is carried out after that. Since in-layer peeling does not develop in the inside, it is very stable also in terms of strength. Therefore, it is excellent in practical performance (opening property) as final products, such as a package bag.

In order to prevent in-layer peeling, it is effective to mix | blend a compatibilizing agent which has affinity for both Ny6 and MXD6 in a raw material. For example, it is also preferable to mix | blend the thermal history article mentioned later in a raw material.

Moreover, when the compounding ratio of a raw material is out of the range mentioned above, the linear cut property and impact resistance of a heat-stretched stretched film will fall, and practical performance as final products, such as a package bag, will run short. Moreover, when extending | stretching conditions, such as a draw ratio, are bad, the tearing strength of a heat-stretched stretched film exceeds 70 N / cm, linear cut property will fall, and practical performance as final products, such as a package bag, will run short.

In addition, the value of tear strength is based on the Elementolf tear strength test (JIS K 7128).

The heat-stretched stretched film of the present invention is a heat-stretched stretched film containing Ny6 and MXD6 as raw materials, wherein the raw material is a virgin raw material composed of 60 to 85 parts by mass of Ny6 and 15 to 40 parts by mass of MXD6, and Ny6 and MXD6. Melt-kneading is carried out, it contains a thermal history article which made melting | fusing point of MXD6 233-238 degreeC, and content of the said thermal history article is 5-40 mass% on the basis of the said raw material whole quantity, It is characterized by the above-mentioned.

Here, the chemical formula of Ny6 is shown in following formula 1, and the chemical formula of MXD6 is shown in following formula 2.

[Formula 1]

[Formula 2]

The above-mentioned virgin raw material means the raw material of the state which is not a mixed raw material which has the history which melt-kneaded by Ny6 and MXD6 mixing with each other normally. For example, even if Ny6 and MXD6 each have the history of melt-kneading alone (for example, a recycled product), they are virgin raw materials when they are mixed and melt-kneaded. However, it is preferable to use as few virgin raw materials as possible from the point of the physical property at the time of becoming a thermosetting stretched film. Also, even though Ny6 and MXD6 have a history of melt kneading by mixing with each other, the melting point of MXD6 is not so low because the kneading is weak, and when it exceeds 238 ° C, these Ny6 and MXD6 still constitute a virgin raw material. It does not constitute a resume.

That is, in this invention, three types (or two types) which added the thermal history article to Ny6 and MXD6 which comprise a virgin raw material are so-called dry blended, and are melt-kneaded and comprise a thermosetting stretched film.

The above-described thermal history article refers to a compound of Ny6 and MXD6 that has once passed through an extruder, and according to the present invention, the melting point of MDX6 resin is maintained in the range of 233 to 238 ° C with a differential scanning calorimeter (DSC). Use the old one.

According to the bithermally stretched film of this invention, since the compounding ratio of Ny6 and MXD6 in a virgin raw material is 60-85 mass parts and 15-40 mass parts of Ny6, it is excellent in linear cut property. And since 5-40 mass% of heat history articles formed by melt-kneading Ny6 and MXD6 are contained with respect to the whole raw material, even if a heat-stretched stretched film is used under severe conditions, in-layer peeling is hard to produce.

Here, in-layer peeling means the phenomenon which causes peeling in a heat-stretched film (nylon layer), when using it in severe conditions after laminating a heat-heat-stretched film with a suitable sealant film. Although the mechanism of in-layer peeling is not necessarily clear, Ny6 and MXD6 are orientated in a layer form in a bithermally stretched film, and it is thought that peeling occurs in the interface.

When such intralayer peeling occurs, the strength of the laminate film becomes unstable, and when a bag is formed, there is a fear that problems such as bag bursting occur under severe use conditions. Such harsh use conditions can be reproduced by, for example, a test for measuring laminate strength (peel strength) of a laminate film.

Moreover, melting | fusing point of MXD6 in a thermal history article is 233-238 degreeC, Preferably it is 235-237 degreeC. When melting | fusing point of MXD6 in a thermal history article becomes less than 233 degreeC, the linear cut property and impact strength of a heat-stretched stretched film fall. Moreover, when melting | fusing point of MXD6 in a thermal history article is 238 degreeC or more, the effect of preventing in-layer peeling will become low.

In the process of producing the thermal history article, if the temperature and pressure during kneading are high, the melting point of the MXD6 in the thermal history article is further lowered.

Here, melting | fusing point of MXD6 in a thermal history article means melting | fusing point measured in the state before melt-kneading with a virgin raw material.

When using this heat-stretched stretched film as a notation of a laminate bag, it is preferable that it is biaxially stretched from the point of impact resistance improvement. In addition, it is preferable to perform biaxial stretching by simultaneous biaxial stretching by the tubular method from the viewpoint of the longitudinal and horizontal strength balance.

Moreover, it is preferable that tearing strength is 70 N / cm or less also in any direction of MD direction and TD direction from a point of a thermosetting point.

In this invention, it is preferable that the compounding ratio of Ny6 and MXD6 in the said heat history article is Ny6: MXD6 = 60-85 mass parts: 15-40 mass parts.

According to the present invention, since the blending ratio of Ny6 and MXD6 in the thermal history article is Ny6: MXD6 = 60 to 85 parts by mass: 15 to 40 parts by mass, it is excellent in linear cutability, impact strength and anti-layer peeling effect. It can be set as a thermosetting stretched film.

When content of MXD6 in a thermal history article is less than 15 mass% (content of Ny6 is 85 mass% or more), the layer-in-layer peeling prevention effect will become low, when it is set as a thermosetting stretched film. When content of MXD6 in a thermal history article is 40 mass% or more (content of Ny6 is less than 60 mass%), the linear cut property and impact strength of a heat-stretched stretched film fall.

The heat-sensitive laminated film of the present invention is characterized in that the above-described heat-stretched stretched film is formed as at least one layer of a plurality of layers.

According to the heat-sensitive laminate film of the present invention, since the heat-oriented stretched film described above is formed as at least one layer of a plurality of layers, even if the laminate film is excellent in linear cutability and impact strength, and used under severe conditions, Intralayer peeling does not occur in a nylon layer.

The heat-resistant bag of the present invention is characterized by using the above-mentioned heat-sensitive laminate film.

According to the heat dissipation bag of the present invention, since the heat dissipation laminate film is used, it is excellent in openability (straight cut property) and in-layer peeling does not occur in the nylon film layer, so that it is stable in terms of strength. It becomes a highly practical thermostable bag.

The manufacturing method of the thermosetting stretched film of this invention is a manufacturing method of the thermosetting stretched film containing Ny6 and MXD6 as a raw material, The said raw material is 60-85 mass parts of Ny6, and 15-40 mass parts of MXD6 (quantum) The sum total contains 100 mass parts of virgin raw materials, and the heat history goods which melt-knead Ny6 and MXD6, and melting | fusing point of MXD6 in the said heat history goods is 233-238 degreeC, and said heat history The content of the product is 5 to 40% by mass based on the total amount of the raw materials, and the biaxial stretching is performed at a stretching ratio of 2.8 times or more in both the MD direction (moving direction of the film) and the TD direction (width direction of the film).

According to the manufacturing method of the thermosetting stretched film of this invention, since it contains Ny6 and MXD6 as a raw material, and is extending | stretching at a predetermined draw ratio, even if the film after manufacture is excellent in linear cut property and comprises a laminated film, The good linear cutability can be maintained. Moreover, the impact resistance is also excellent as long as it is biaxial stretching to MD direction and TD direction. In addition, since the raw material contains a predetermined heat history product, even when the laminate film (bag) is handled under severe conditions, the nylon layer does not cause in-layer peeling.

In addition, although the draw ratio of MD direction and / or TD direction is 2.8 times or more, Preferably it is 3.0 times or more. When the draw ratio is smaller than 2.8 times, the linear cutability is inferior. Moreover, even if it is biaxial stretching, impact resistance falls and a problem arises in practical use. Moreover, extending | stretching by simultaneous biaxial stretching by a tubular method is preferable at the point of the strength balance of MD direction and TD direction.

As described above, the thermotropic stretched film of the present invention is not particularly limited to the production method as long as it satisfies conditions such as a compounding amount of Ny6 and MXD6 in the raw material. However, the best mode for carrying out the present invention will be described below. It describes in detail.

[First Embodiment]

The bithermally stretched film which concerns on this embodiment contains Ny6 and MXD6 as a raw material, This raw material melt-kneades the virgin raw material which consists of 60-85 mass parts of Ny6, and 15-40 mass parts of MXD6, and Ny6 and MXD6. The melting point of the MXD6 in the thermal history product is 233 to 238 ° C, and the content of the thermal history product is 5 to 40 mass% based on the total amount of the raw material. Here, the chemical formula of Ny6 is shown in Formula 3, and the chemical formula of MXD6 is shown in Formula 4.

[Equation 3]

[Formula 4]

The blending ratio of Ny6 and MXD6 in a virgin raw material needs to be 60-85 mass parts and 15-40 mass parts of ND6 from a viewpoint of the linear cut and impact strength of the film after film forming. When MXD6 in a virgin raw material is less than 15 mass parts, linear cut property will be inferior. In addition, when MXD6 is more than 40 mass parts, impact strength will fall significantly and its utility will fall short.

It is preferable that both Ny6 and MXD6 which comprise a virgin raw material dry-blend what is pellet form.

The raw material needs to contain a thermal history product obtained by melt kneading Ny6 and MXD6. Moreover, melting | fusing point of MXD6 in a thermal history article is 233-238 degreeC, Preferably it is 235-237 degreeC. When melting | fusing point of MXD6 in a thermal history article becomes less than 233 degreeC, the linear cut property and impact strength of a heat-stretched stretched film fall. Moreover, when melting | fusing point of MXD6 in a thermal history article becomes 238 degreeC or more, the effect of preventing in-layer peeling will become low.

Furthermore, it is necessary to contain 5-40 mass% of heat history articles formed by melt-kneading Ny6 and MXD6 with respect to the whole raw material. If the thermal history article is less than 5% by mass, after using the heat-stretched stretched film as a laminate film, it is easy to cause in-layer peeling when used under severe conditions. Moreover, when a thermal history article exceeds 40 mass%, the linear cut property and impact strength of a heat-stretched stretched film fall.

Moreover, it is preferable that the compounding ratio of Ny6 and MXD6 in a thermal history article is Ny6: MXD6 = 60-85 mass parts: 15-40 mass parts.

Since the blending ratio of Ny6 and MXD6 in a thermal history product is 60-85 mass parts of Ny6, and 15-40 mass parts of MXD6, it is a heat-stretched stretch film excellent in linear cut property, impact strength, and layer peeling prevention effect. can do.

When content of MXD6 in a thermal history article is less than 15 mass% (content of Ny6 is 85 mass% or more), the layer-in-layer peeling prevention effect will become low, when it is set as a thermosetting stretched film. When content of MXD6 in a thermal history article is 40 mass% or more (content of Ny6 is less than 60 mass%), the linear cut property and impact strength of a heat-stretched stretched film fall.

This thermal history article may be a thing which recycled the heat-stretched stretched film obtained by this embodiment. In addition, in order to dry-blend a thermal history article with the pellet of Ny6 and the pellet of MXD6 favorably, it is preferable to process and use the shape of a thermal history article into a pellet form. For example, the heat-stretched stretched film obtained by the present embodiment may be finely cut and compressed to have such a shape.

When using this heat-stretched stretched film as a notation of a laminate bag, it is preferable that it is biaxially stretched. It is preferable to perform biaxial stretching by simultaneous biaxial stretching by the tubular method in the aspect of the longitudinal and horizontal strength balance. Moreover, it is preferable that tearing strength is 70 N / cm or less in any direction of MD direction and TD direction from the point which improves linear cut property.

Moreover, a required additive can be added suitably to a thermotropic stretched film. Examples of such additives include antiblocking agents (such as inorganic fillers), water repellents (such as ethylenebisstearic acid esters), and lubricants (calcium stearate and the like).

Such a thermotropic stretched film can be manufactured using the biaxial stretching apparatus of the tubular system as shown in FIG. 1, for example. For example, it can manufacture by melt-extruding the mixture which dry-blended the pellet of Ny6, the pellet of MXD6, and a thermal history product, and then biaxially stretches the cooled original film at the magnification of 2.8 times or more in both MD direction and TD direction. .

According to this embodiment, the blending ratio of Ny6 and MXD6 in a virgin raw material is 60-85 mass parts of Ny6, and 15-40 mass parts of MXD6, and heat history goods formed by melt-kneading Ny6 and MXD6 to this In addition, since melting | fusing point of MXD6 in this heat history article is 233-238 degreeC, and content of a heat history article is 5-40 mass% on the basis of the raw material whole quantity, it is excellent in linear cut property and impact strength, Even if used under severe conditions, a thermosetting stretched film which is unlikely to cause in-layer peeling is obtained.

[Second Embodiment]

The heat-resistant laminated film of this invention contains a heat-oriented stretched film as at least 1 layer, and may be several layers, such as 2 layers and 3 layers. 2-4, the bithermal laminated film 100, 200, 300 which concerns on this embodiment was shown. Here, for example, as shown in FIG. 2, as shown in FIG. 2, the two-layered structure which made the 1st layer into the heat-stretched stretched film 18, and the 2nd layer into various sealant films 19, 1st, As shown in FIG. 3, the three-layered structure which made the various base film 20 the layer into the heat-stretched stretched film 18 the 2nd layer, and the 3rd layer into the various sealant film 19, as shown in FIG. It is good also as a three-layered structure which made the stretched film 18 and the 2nd layer into the various base films 20, and the 3rd layer into the various sealant films 19. FIG.

As a material of the base film 20, PET (polyethylene terephthalate), EVOH (ethylene-vinyl acetate copolymer saponification), PVA (polyvinyl alcohol), PP (polypropylene), PVDC (polyvinyl chloride), for example Biaxial or uniaxially oriented films or unstretched films such as leadene), HDPE (high density polyethylene), and PS (polystyrene) can be used. In addition to these resin films, a metal film such as aluminum foil may be used.

As a material of the sealant film 19, L-LDPE (linear low density polyethylene), LDPE (low density polyethylene), HDPE (high density polyethylene), EVA (ethylene-vinyl acetate copolymer), PB (polybutene-1), CPP (unstretched polypropylene), ionomers, PMMA (polymethylmethacrylate) and the like and mixtures thereof can be used. As a lamination method of the said thermosetting laminate film, an extrusion laminate, a hot melt laminate, a dry laminate, a wet laminate, etc. are mentioned, for example.

According to this embodiment, since the above-mentioned heat-stretched stretched film 18 is formed as at least one layer of a plurality of layers, the heat-resistant laminate films 100, 200, and 300 are heat-resistant and a straight cut also as a laminate film. It is excellent in resistance and impact strength, and does not cause in-layer peeling to the nylon layer even when used under severe conditions. That is, when a bag is manufactured using this dither laminated film (100, 200, 300), it can be used as a dither bag 400 (FIG. 5) which utilized the characteristic.

Although the best structure for implementing this invention etc. is disclosed by the above description, this invention is not limited to this. That is, the present invention has been mainly described with respect to specific embodiments, but those skilled in the art will appreciate the embodiments described above in terms of materials, quantities, and other detailed configurations without departing from the scope of the technical idea and the object of the present invention. Various variations can be made.

Therefore, the base materials limiting the materials, the layer structure, and the like described above are exemplarily described in order to facilitate understanding of the present invention, and are not intended to limit the present invention. The description by the name except a limitation of all is included in this invention.

For example, in this embodiment, although the biaxially stretched film was manufactured as a thermotropic stretched film, a uniaxially stretched film may be sufficient. For example, in the heat-heating bag of FIG. 5, you may use the uniaxial stretched film orientated in the TD direction as a display material film. It is preferable when linear cutability is especially important.

In addition, in this embodiment, although the tubular system was employ | adopted as a biaxial stretching method, a tenter system may be sufficient. Moreover, as a extending | stretching method, simultaneous biaxial stretching may be sufficient and sequential biaxial stretching may be sufficient as it.

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, this invention is not limited at all by these examples.

Example 1

(Production of Heat-stretched Stretched Film)

The total amount of the raw material of the thermal history product (the melting point of MXD6 is 236 DEG C) which has been melt-blended and pelletized once by mixing the Ny6 pellets and MXD6 pellets at a ratio of 70 parts by mass and 30 parts by mass, respectively. It mix | blended 15 mass% with respect to. After melt-kneading this dry blended product at 270 degreeC in the extruder, the melt was extruded from the dice | dies as a cylindrical film, it was then quenched with water, and the disk film was produced.

In addition, the melting point of MXD6 was measured by raising the temperature from 50 ° C to 280 ° C at a heating rate of 10 ° C / min using a differential scanning calorimeter (DSC) manufactured by Parkin Elma. In all, the value in a first run was made into melting | fusing point.

The Ny6 used was UBE HUNGSAN Co., Ltd. nylon 6 [UBE nylon 1023FD (brand name), relative viscosity (eta) = 3.6], The thing used as MXD6 was Mitsubishi Gas Chemical Co., Ltd. metaxylylene adipamide (MX nylon) 6007 (brand name) and relative viscosity ηr = 2.7].

In addition, the compounding ratio of Ny6 and MXD6 was made into 70 mass parts and 30 mass parts, respectively, and was what extruded at 270 degreeC using 40φEX and single screw (manufactured by Yamaguchi Corporation) as a thermal history product.

Next, as shown in FIG. 1, after this disk film 11 is inserted through a pair of nip rolls 12, it heats with the heater 13, pressurizing a gas inside, and stretches a dog Simultaneous biaxial stretching in the MD direction and the TD direction by the tubular method by blowing air 15 from the air ring 14 and expanding it in the bubble 16 at the starting point and collecting it in a pair of downstream nip rolls 17. Was performed. The magnification at the time of stretching was 3.0 times in both the MD direction and the TD direction.

Next, this stretched film was put into a tenter type heat treatment furnace (not shown), and heat-setting was performed at 210 degreeC, and the heat-stretched stretched film 18 (referred to as the stretched film 18 after this) which concerns on a present Example was obtained. .

(Production of the thermosetting laminate film)

Next, let this stretched film (18; thickness 15 micrometers) make a notation material film, an L-LDPE film (Uni-Lax LS-711C (brand name), Idemitsu Unitec Co., Ltd. product, thickness 50 micrometers) the sealant film, Both were dry-laminated and the bithermal laminated film (henceforth a laminated film) which concerns on a present Example was obtained. As the adhesive for dry lamination, Mitsui Takeda Chemical Co., Ltd. product Takerak A-615 / Takenate A-65 (mixture ratio 16/1) was used. In addition, the laminated film after dry lamination performed the aging at 40 degreeC for 3 days.

〔Assessment Methods〕

(Extension moldability)

The stability of the bubble at the time of film forming of the stretched film 18 was evaluated as stretch moldability. Specifically, A was considered to be stable and C was evaluated to be unstable and unstable. In addition, initially, even if there was fluctuation of a bubble, it was set as B which was able to stabilize a bubble by fine control.

(Impact strength)

The impact strength was measured with respect to the stretched film 18.

It was performed by hitting a semi-spherical pendulum (1/2 inch in diameter) to a fixed ring-shaped film using a film impact tester manufactured by Toyo Seiki Co., Ltd., and measuring the impact strength required for the punching of the film. . And the impact strength evaluated 45,000 J / m or more as A and less than 45,000 J / m as C. When this impact strength becomes smaller than 45,000 J / m, the performance as a marking material will fall, and the utility as a liquid packaging base material will run short.

(Straight cut)

Linear cutability was performed with respect to the stretched film 18. FIG.

As shown in FIG. 6, after making the cut surface 21 in the film 18 of 20 cm width at predetermined space | interval (Ws; for example, 2 cm space | interval), and tearing the film 18 along these cut surfaces 21, the film The width We of the other end 22 of the piece 18A is measured, and the deviation α from the original interval Ws is obtained by the following equation.

[Formula 5]

α = [│Ws-We│ / Ws] × 100

This measurement was carried out on the ten pieces of film 18A, and A ⁺ (linear cutability is very good) and ± 10%? Α? (Good linear cutability) and the thing ((%) more than +/- 30% were evaluated by C (bad linear cutability). When α (%) exceeds ± 30%, it becomes difficult to cut the film 18 in a straight line.

(In-layer peeling)

A 15-mm-wide single-sheet test piece was cut out from the laminate film described above, and the end portion thereof was subjected to interfacial peeling by several cm by hand, and separated into a labeling film (stretched film 18) and a sealant film. Then, each film piece was set in the tension tester (Instron universal testing machine type 1123), and the peeling test of the laminated part was performed at the speed | rate of 300 mm / min (90 degree peeling).

When in-layer peeling generate | occur | produces inside a marking material film at the time of peeling test, since peeling strength falls rapidly, the presence or absence of in-layer peeling generation can be discriminated whether or not such a behavior showed. For example, when the peeling strength was about 7 N / m at the time of the start of a peeling test, it can be judged that in-layer peeling generate | occur | produced when the peeling test suddenly decreased to about 1-2 N / m.

And it evaluated as A which did not show the behavior of layer peeling in the inside of a marking material film, and C which showed the behavior of layer peeling.

(Tear strength)

The tear strength was measured with respect to the stretched film 18.

Based on the Elementolpe tear strength test (JIS K 7128), the tear strength in the MD direction and the TD direction of the stretched film 18 was measured. And tear strength evaluated 70 N / cm or less as A and 71 N / cm or more as C. It is preferable that this tear strength is 70 N / cm or less from the point which improves linear cut property. However, when tear strength is 71 N / cm or more, linear cut property will fall and the practical performance as a liquid packaging base material will run short.

(Comprehensive evaluation)

The comprehensive evaluation which made A or more grades A or more in all five items of the above drawability, impact strength, linear cutability, in-layer peeling, and tear strength was performed. If any one of 5 items mentioned above exists C, it was set as C as a comprehensive evaluation.

[Examples 2-6, Comparative Examples 1-6]

In Example 1, the mixing amount of the Ny6 pellets, the MXD6 pellets, and the thermal history article and the melting point of MXD6 in the thermal history article were changed to form a film by the same manufacturing process as in Example 1. Evaluation test was done similarly to Example 1. In Table 1, the Example and Table 2 show the manufacturing conditions of a comparative example.

1) Melting point of MDX6 in thermal history products

1) Melting point of MDX6 in thermal history products

[Evaluation results]

As shown in Table 1 and Table 2, the stretched film 18 which concerns on a present Example contains Ny6 and MXD6 as a raw material, This raw material consists of 60-85 mass parts of Ny6 and 15-40 mass of MXD6. The raw material and the heat history product which melt-kneads Ny6 and MXD6 are contained, melting | fusing point of MXD6 in a heat history article is 233-238 degreeC, and content of a heat history article is 5- based on the said raw material whole quantity basis. Since it exists in the range of 40 mass%, it is excellent also in any of extending | stretching moldability, impact strength, linear cut property, the anti-layer peeling effect, and tear strength.

On the other hand, since the comparative example does not satisfy the conditions mentioned above, there exists a problem in the physical property of the stretched film 18 in all. Specifically, since the comparative example 1 does not contain a thermal history product as a raw material, in-layer peeling is caused in a nylon film layer. In Comparative Example 2, since the content of the thermal history article is large at 45% by mass, the impact strength, the linear cutability, and the tear strength are inferior. In Comparative Example 3, since the melting point of MXD6 in the thermal history article was low at 232 ° C, linear cutability and tear strength were inferior. In Comparative Example 4, since the content of the thermal history product was small, in-layer peeling occurred in the nylon film layer similarly to Comparative Example 1. In Comparative Example 5, since the melting point of the thermal history article is considerably low at 210 ° C, impact strength, linear cutability, and tear strength are inferior. In addition, the stretchability is poor. In the comparative example 6, since there is too much content of Ny6, linear cut property and tear strength are inferior.

According to the present invention, a dither stretched film having excellent linear cutability and not causing in-layer peeling in the stretched film layer, a dither laminate film using this, a dither bag, and a dither stretched film can be obtained.

Claims (6)

As a thermosetting stretched film containing nylon 6 (hereinafter also referred to as Ny6) and metaxylyleneadipamide (hereinafter also referred to as MXD6) as a raw material, The said raw material is a virgin raw material which consists of 60-85 mass parts of Ny6, and 15-40 mass parts of MXD6 (total of a quantum is 100 mass parts), Contains a thermal history product obtained by melt kneading Ny6 and MXD6, Melting | fusing point of MXD6 in the said thermal history article is 233-238 degreeC, Content of the said thermal history article is 5-40 mass% on the basis of the said raw material whole quantity, The heat-stretched stretched film characterized by the above-mentioned. The heat-stretched film according to claim 1, wherein the blending ratio of Ny6 and MXD6 in the thermal history article is Ny6: MXD6 = 60 to 85 parts by mass: 15 to 40 parts by mass. The heat-heat-stretched film of Claim 1 or 2 is formed as at least one layer of multiple layers, The heat-resistant laminate film characterized by the above-mentioned. The heat-resistant bag characterized by using the heat-resistant laminate film of Claim 3. As a method for producing a dithermic stretched film containing nylon 6 (hereinafter also referred to as Ny6) and metaxylyleneadipamide (hereinafter also referred to as MXD6) as a raw material, The said raw material is a virgin raw material which consists of 60-85 mass parts of Ny6, and 15-40 mass parts of MXD6 (total of a quantum is 100 mass parts), Contains a thermal history product obtained by melt kneading Ny6 and MXD6, The melting point of MXD6 in the thermal history article is 233 to 238 ° C, and The content of the thermal history article is 5 to 40% by mass based on the total amount of the raw materials, The manufacturing method of the heat-stretched stretched film characterized by extending | stretching at the draw ratio 2.8 times or more in MD direction (moving direction of a film) and / or TD direction (width direction of a film). delete

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