JP2008155549A - Polyethylene-based medical container and laminated film used for it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyethylene-based medical container which is excellent in drop bag strength and transparency, is hard to block the inner surface of a medicine chamber, easy to open it, and the outer surface of the medicine chamber having blocking characteristics, being hard to slip between the outer surfaces, easy to be attracted to a suction pad, and to certainly open it, and a laminated film used for it. <P>SOLUTION: The polyethylene-based medical container is formed of a laminated film made of an inner layer containing high density polyethylene as a principal component having a melting point of 128°C or higher, a middle layer containing straight chain low-density polyethylene having density of 0.920 g/cm<SP>3</SP>or lower as a principal component of a copolymer of ethylene manufactured by a metallocene-based catalyst and an α-olefin of 4C or more, and an outer layer containing straight chain low-density polyethylene having a melting point of 128°C or lower as a principal component. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a polyethylene-based medical container and a laminated film used therefor, and in particular, a bag-like polyethylene-based medical container that contains and uses a chemical solution such as blood, physiological saline, injection solution, and the like. The present invention relates to a laminated film.

  A so-called infusion bag having a bag shape as shown in FIG. 1 is widely used as a medical container. The bag-like medical container 10 in FIG. 1 includes a port 11 provided with a rubber stopper for inserting and discharging a drip tube with a needle or the like, or injecting another chemical solution, and a chemical solution such as an infusion solution. A medicine chamber 12 is provided. Further, the peripheral edge of the medical container 10 is liquid-tightly closed by a strong seal portion 13 that does not peel even when a force is applied to the drug chamber 12 from the outside. Further, the strong seal portion 13 is provided with a suspension hole 14 for suspending the medical container. The port 11 and the drug room 12 are usually made of a polyethylene resin, and the medical container 10 including the port 11 and the drug room 12 is preferred because it has few effluents from the container and high hygiene.

As a bag-like medical container using such a polyethylene resin, the following containers have been proposed.
A medical container comprising a laminate in which the resin density of the inner and outer layers is 0.92 g / cm ³ or more and the resin density of the intermediate layer is less than 0.92 g / cm ³ (see Patent Document 1).
Linear low-density polyethylene having a resin density of the inner and outer layers of 0.92 to 0.94 g / cm ³ and a resin of the middle layer of 0.89 to 0.93 g / cm ³ and a density of 0.86 to 0.89 g / cm ³ A laminate for a medical container using a three-layer film made of a blend with a cm ³ elastomer. (See Patent Document 2).
The inner layer having a density of 0.945 g / cm ³ or more, and the resin of the intermediate layer is 0.920 g / cm ³ or less linear low density polyethylene and less than 15 wt% density of 0.945 g / cm ³ or more high-density polyethylene A medical bag made of a blend of (see Patent Document 3).
Laminates and containers comprising an inner layer of high-density polyethylene, an intermediate layer of a density of less than 0.920 g / cm ^{3 and a} linear low-density polyethylene obtained by a single-site catalyst, and an outer layer of a material containing high-density polyethylene (see Patent Document 4) .)

  By the way, a bag-like medical container is generally manufactured by inserting a port into a chamber interior made of a film or a sheet (hereinafter referred to as “film”), holding it, and sealing it. The In this case, the port is inserted by pulling and opening the inner surface of the medicine chamber. In this opening, if the blocking between the interior surfaces of the medicine chambers is too strong, the opening cannot be made well, and it becomes difficult to insert the port. The opening of the chamber is usually performed by adsorbing both outer surfaces of the chamber to the suction pad and peeling off the chamber surface. Accordingly, even when the outer surface of the chamber is not sufficiently adsorbed by the adsorption pad, the opening cannot be performed well.

In addition, the fact that the chamber is easy to open is also required when filling a medical solution into a bag-shaped medical container, and if the blocking between the chamber interiors is strong, the solution overflows and may interfere with filling. .
In addition, when transporting a plurality of bag-shaped medical containers in bulk, if they are transported in an irregular manner, there is a problem that the ports collide with each other, the port and the bag portion are damaged, and the transport efficiency is reduced. . Therefore, as shown in FIGS. 2 (a) and 2 (b), a method of transporting the medical container 10 by forming a stacking shape in which the ports 11 are shifted little by little is employed. In addition, when the blocking between the outer surfaces of the medical chambers of each medical container is weak, there is a problem that the medical containers are separated.
JP-A-62-64363 Japanese Patent No. 2790947 Japanese Patent Laid-Open No. 5-293160 JP 2003-237002 A

  However, the laminates and medical containers described in Patent Documents 1 to 4 described above cannot sufficiently satisfy these problems, and can be a polyethylene-based medical container that can solve these problems. Is required. Bag-like polyethylene medical containers are also required to have a falling bag strength and transparency.

  The present invention has been made in view of such a situation, and has excellent bag drop strength and transparency. It is an object of the present invention to provide a polyethylene-based medical container that has a blocking property that is easily adsorbed and that can be surely opened, and a laminated film used therefor.

In order to solve the above-mentioned problems, the present inventors reduce the blocking strength of the inner surface of the chamber and make a bag in a medical container using a polyethylene-based laminated film having an appropriate blocking characteristic on the outer surface of the chamber. Thus, the inventors have found that the above problem can be solved, and have completed the present invention.
That is, the polyethylene-based medical container of the present invention is composed of an inner layer mainly composed of high-density polyethylene having a melting point of 128 ° C. or higher, a copolymer of ethylene produced by a metallocene catalyst and an α-olefin having 4 or more carbon atoms. A laminated film comprising a middle layer composed mainly of linear low density polyethylene having a density of 0.920 g / cm ³ or less and an outer layer mainly composed of linear low density polyethylene having a melting point of 128 ° C. or less. It is formed by.

Also, the middle layer is, density 0.900 g / cm ³ or more, preferably contains a high-pressure low-density polyethylene is 0.930 g / cm ³ or less.
Furthermore, it is preferable that the density of the linear low density polyethylene which is the main component of the outer layer is 0.900 g / cm ³ or more and 0.925 g / cm ³ or less.
Further, the outer layer, density 0.900 g / cm ³ or more, preferably contains a high-pressure low-density polyethylene is 0.930 g / cm ³ or less.
Furthermore, it is preferable that the chamber has two or more chambers for storing the chemical solution, and each chamber is separated by an easily peelable partition seal.

The polyethylene film for medical containers according to the present invention includes an inner layer mainly composed of high-density polyethylene having a melting point of 128 ° C. or higher, ethylene produced with a metallocene catalyst, and α-olefin having 4 or more carbon atoms. An intermediate layer mainly composed of linear low density polyethylene having a density of 0.920 g / cm ³ or less and an outer layer mainly composed of linear low density polyethylene having a melting point of 128 ° C. or less. It is characterized by being laminated.

  According to the present invention, the bag drop strength and transparency are excellent, the inside of the chamber is difficult to block and easy to open, and the outside of the chamber has a blocking property that the outside surfaces are not easily slipped from each other and easily adsorbed to the adsorption pad It is possible to provide a polyethylene-based medical container capable of reliably opening and a laminated film used therefor.

Hereinafter, the present invention will be described in detail.
FIG. 1 is an example of a polyethylene medical container (hereinafter referred to as “medical container”) 10 of the present invention. The medical container 10 of the present invention includes a port 11 and a drug room 12. Further, the peripheral edge of the medical container 10 is liquid-tightly closed by the strong seal portion 13. Further, the strong seal portion 13 is provided with a suspension hole 14 for hanging the medical container.
The chamber 12 includes a polyethylene-based medical container laminated film (hereinafter referred to as “laminated film”) 20, an example of which is shown in FIG. 3. The laminated film 20 is a copolymer of an inner layer 21 mainly composed of high-density polyethylene having a melting point of 128 ° C. or higher, an ethylene produced by a metallocene catalyst, and an α-olefin having 4 or more carbon atoms, and has a density. It consists of an intermediate layer 22 whose main component is linear low density polyethylene of 0.920 g / cm ³ or less and an outer layer 23 whose main component is linear low density polyethylene whose melting point is 128 ° C. or lower.

<Laminated film>
(Inner layer)
The inner layer 21 on the liquid contact side of the laminated film 20 forming the polyethylene medical container 10 according to the present invention is mainly composed of high-density polyethylene having a melting point of 128 ° C. or higher. In addition, about the temperature range of melting | fusing point, although the range of the commercially available high-density polyethylene can be made into an upper limit, since it is excellent in the moldability of a bag-shaped medical container, Preferably it is 128-138 degreeC, More preferably 130-135 ° C.
In the present invention, the melting point is a differential scanning calorimeter (hereinafter referred to as “DSC”) as a measuring device, and the sample is held at a temperature about 30 ° C. higher than the approximate melting point for 10 minutes, and then at a rate of 10 ° C./min. It is the temperature of the peak that appears when it is cooled to 30 ° C. and then heated to a temperature 30 ° C. higher than the melting point at a rate of 10 ° C./min.

The high density polyethylene preferably has a density of 0.940 g / cm ³ or more and a molecular weight distribution (Mw / Mn) of 4 or less. The melt flow rate (hereinafter referred to as “MFR”) is preferably from 0.1 to 10 g / 10 minutes, more preferably from 0.5 to 5.0 g / 10 minutes. If it is less than 0.1 g / 10 minutes, the resin pressure at the time of extrusion molding increases and the moldability decreases. On the other hand, if it is larger than 10 g / 10 min, the bubble stability is lowered.
In the present invention, the density is a value measured according to JIS K 7112, Mw / Mn is measured by gel permeation chromatography (hereinafter referred to as “GPC”), and a calibration curve using polystyrene as a standard sample is obtained. The ratio of the weight average molecular weight Mw and the number average molecular weight Mn calculated using MFR is a value measured at a load of 21.18 N and a temperature of 190 ° C. in accordance with JIS K 7210.

In addition, although it is preferable to use only a high density polyethylene for the inner layer 21, as another resin as needed, when the whole inner layer 21 is 100 mass%, it is 35 mass% or less, Preferably it is 25 mass% or more. Preferably, 15% by mass or less of linear low density polyethylene may be included. Such a linear low density polyethylene is produced with a metallocene catalyst or a Ziegler-Natta catalyst, and preferably has an MFR of 0.1 to 10 g / 10 min and a density of 0.925 g / It is preferable to exceed cm ³ , and the melting point is preferably 125 ° C. or higher, more preferably 128 ° C. or higher.

(Middle layer)
The middle layer 22 forming the intermediate portion of the laminated film 20 forming the polyethylene medical container 10 in the present invention is a copolymer of ethylene and α-olefin having 4 or more carbon atoms produced with a metallocene catalyst. The main component is a linear low density polyethylene (hereinafter also referred to as “m-LLDPE”) of 0.920 g / cm ³ or less.
m-LLDPE is produced with a metallocene catalyst, a so-called single site catalyst, and α-olefins include butene-1, 4-methylpentene-1, pentene-1, hexene-1, octene-1 Etc. In addition, you may use a commercial item for m-LLDPE. Examples of commercially available m-LLDPE include Evolue (manufactured by Prime Polymer Co., Ltd.), Kernel (manufactured by Nippon Polyethylene Co., Ltd.), Harmolex (manufactured by Nippon Polyethylene Co., Ltd.), Umerit (manufactured by Ube Industries, Ltd.), Affinity (Dow Chemical Japan Co., Ltd.).

The density of m-LLDPE is 0.920 g / cm ³ or less. If the density is 0.920 g / cm ³ or more, the bag drop strength and transparency are lowered. The MFR of m-LLDPE is preferably from 0.1 to 10.0 g / 10 minutes, more preferably from 0.5 to 5.0 g / 10 minutes. If it is less than 0.1 g / 10 min, the resin pressure increases during extrusion molding such as inflation molding of the laminated film 20 and the moldability decreases. On the other hand, if it is larger than 10.0 g / 10 min, the bubble stability is lowered in the inflation molding.

Although it is preferable to use substantially only m-LLDPE for the middle layer 22, a high pressure method low density polyethylene can be blended. By blending the high pressure method low density polyethylene, the molding stability is improved. High-pressure low density polyethylene has a density of 0.900 g / cm ³ or more, preferably 0.930 g / cm ³ or less.
The content of the high-pressure low-density polyethylene used for the middle layer 22 is 35% by mass or less, preferably 25% by mass or less, more preferably 15% by mass or less when the entire middle layer 22 is 100% by mass. If it exceeds 35 mass%, the falling bag strength tends to be reduced.

(Outer layer)
The outer layer 23 on the outer side of the laminated film 20 forming the polyethylene medical container 10 in the present invention is mainly composed of linear low density polyethylene (hereinafter sometimes referred to as “LLDPE”) having a melting point of 128 ° C. or less. To do. The linear low density polyethylene used for the outer layer 23 here is one produced by a normal Ziegler-Natta catalyst. A linear low density polyethylene having a melting point of 128 ° C. or lower tends to have a smooth surface after film formation, and has excellent stacking properties and adsorption properties with an adsorption pad. The melting point is preferably from 100 to 128 ° C, more preferably from 100 to 125 ° C. When the melting point is 100 ° C. or higher, heat resistance sufficient to withstand high-pressure steam sterilization performed in the field of medical containers can be more easily satisfied.

LLDPE is preferably a copolymer of ethylene and an α-olefin having 3 or more carbon atoms, and examples of the α-olefin include propylene, butene-1, 4-methylpentene-1, pentene-1, hexene-1, Examples include octene-1.
The density of LLDPE is preferably 0.900 g / cm ³ or more and 0.925 g / cm ³ or less. When the density of LLDPE is less than 0.900 g / cm ³ , as shown in FIG. 2, when the medical containers 10 are aligned in a stacking manner, the outer surfaces of the drug chamber 12 are too blocked to be whitened when peeled off. When it is larger than 0.925 g / cm ³ , blocking between the outer surfaces of the chamber 12 is lowered, and the stacking property is lowered.

  The MFR of LLDPE is preferably from 0.1 to 10.0 g / 10 minutes, more preferably from 0.5 to 5.0 g / 10 minutes. If it is less than 0.1 g / 10 minutes, the extrusion pressure increases during extrusion molding such as inflation molding of the laminated film 20 and the moldability decreases. On the other hand, if it is larger than 10.0 g / 10 min, the bubble stability is lowered in the inflation molding.

For the outer layer 23, it is preferable to use substantially only LLDPE, but high-pressure low-density polyethylene can be blended. By blending the high pressure method low density polyethylene, the molding stability is improved. High-pressure low density polyethylene has a density of 0.900 g / cm ³ or more, preferably 0.930 g / cm ³ or less.
The MFR of the high-pressure method low-density polyethylene is preferably from 0.1 to 10.0 g / 10 minutes, and more preferably from 0.5 to 5.0 g / 10 minutes because of excellent molding stability.
The content of the high-pressure method low-density polyethylene used for the outer layer 23 is 35% by mass or less, preferably 25% by mass or less, more preferably 15% by mass or less when the entire outer layer 23 is 100% by mass. When it exceeds 30% by mass, the stacking property tends to be lowered.

(Laminated film manufacturing method)
Examples of the method for producing the laminated film 20 of the present invention include a water-cooled or air-cooled coextrusion inflation method, a coextrusion T-die method, a dry lamination method, and a coextrusion lamination method. The water-cooled coextrusion inflation method and the coextrusion T-die method are preferred from the viewpoints of transparency, economy, and hygiene.

  The thickness of the laminated film 20 thus obtained is generally preferably 100 to 400 μm, but the thickness can be appropriately increased or decreased according to the purpose of use. The thickness ratio of each layer is not particularly limited, but the middle layer is preferably configured to be the thickest layer in terms of thickness.

  The polyethylene resin used for the inner layer 21, the middle layer 22 and the outer layer 23 of the laminated film 20 of the present invention is a known additive that is usually used, for example, an antistatic agent, as long as the effects of the present invention are not impaired. Antioxidants, lubricants, antiblocking agents, antifogging agents and the like can be appropriately blended as necessary.

<Medical container>
The medical container 10 of the present invention heat seals the inner layers of the above-described laminated film 20 mainly composed of high-density polyethylene to form a drug chamber 12 and a strong seal portion 13 as shown in FIG. 11 can be inserted and heat-sealed to attach a container having a predetermined shape and size. A chemical solution is accommodated in the manufactured container. Examples of the chemical solution include physiological saline, electrolyte solution, dextran preparation, mannitol preparation, amino acid preparation and other infusion solutions, blood components, and the like.

In addition, the medical container 10 of the present invention can be a medical container (medical multi-chamber container) having two or more drug rooms for storing a chemical solution. For example, as shown in FIG. 4, a medical multi-chamber container 30 having a first chamber 32a and a second chamber 32b as the chamber 32 can be exemplified. Similar to the medical container 10, the medical multi-chamber container 30 includes a port 31, and the periphery thereof is liquid-tightly closed by a strong seal portion 33. Further, the strong seal portion 33 is provided with a suspension hole 34 for hanging the medical container.
As described above, in the medical multi-chamber container 30 having two or more chambers 32, two or more kinds of chemical solutions that cannot be dissolved or mixed until immediately before use due to a change in the composition can be peeled off, and two layers are laminated. In a sealed state by holding the film in a separate chamber separated by a partition means 35 such as a clamp, a partition member such as a communicable partition member, and by connecting the partition means 35 during use, In addition, two or more kinds of chemical solutions can be mixed and used without generating foreign matters. Further, instead of the chemical solution, at least one drug room may be a powder such as antibiotics. In addition, as the partition means 35, the peelable easily peelable partition seal is preferable.

  As described above, according to the present invention, the opening of the bag is reduced by reducing the blocking strength of the inner surface of the chamber and making the bag into a medical container using a polyethylene-based laminated film having an appropriate blocking characteristic of the outer surface of the chamber. Properties, stacking properties during packaging and transport, transparency, and a polyethylene medical container excellent in bag drop strength and a laminated film used therefor are obtained.

Examples of the present invention will be described below, but the present invention is not limited to these examples.
Here, the physical property measuring method of the polyethylene-type resin used for the Example is shown below.
(MFR)
According to JIS K 7210, the measurement was performed at a temperature of 190 ° C. and a load of 21.18 N.
(density)
Measured according to JIS K 7112.
(Melting point)
Using “DSC7” manufactured by Perkin Elmer as a measuring device, the sample was held at a temperature about 30 ° C. higher than the approximate melting point for 10 minutes, cooled to 30 ° C. at a rate of 10 ° C./minute, and then 10 ° C. / When the temperature was raised to a temperature approximately 30 ° C. higher than the melting point at a rate of minutes, the temperature of the peak that appeared was defined as the melting point (hereinafter referred to as “Tm”).
(Mw / Mn)
The ratio between the weight average molecular weight Mw and the number average molecular weight Mn was calculated using a calibration curve measured by GPC and polystyrene as a standard sample. The measurement apparatus and measurement conditions are shown below.
Measuring apparatus: “150 type” manufactured by Waters.
Solvent: orthodichlorobenzene.
Column temperature: 135 ° C.
Column: “GMMHR-1” manufactured by Tosoh Corporation.

The polyethylene resin used in the examples is shown below.
PE-1: high density polyethylene, density = 0.950 g / cm ³ , MFR = 3.0 g / 10 min, Tm = 130 ° C., Mw / Mn = 3.5.
PE-2: high density polyethylene, density = 0.960 g / cm ³ , MFR = 0.8 g / 10 min, Tm = 135 ° C., Mw / Mn = 4.2.
PE-3: linear low-density polyethylene composed of ethylene and hexene-1 produced with a Ziegler-Natta catalyst, density = 0.920 g / cm ³ , MFR = 2.0 g / 10 min, Tm = 121 ° C.
PE-4: linear low density polyethylene consisting of ethylene and hexene-1 produced with a Ziegler-Natta catalyst, density = 0.927 g / cm ³ , MFR = 2.1 g / 10 min, Tm = 122 ° C.
PE-5: High-pressure method low-density polyethylene, density = 0.922 g / cm ³ , MFR = 0.7 g / 10 min, Tm = 107 ° C.
PE-6: Single-site linear low-density polyethylene composed of ethylene and hexene-1, density = 0.918 g / cm ³ , MFR = 2.5 g / 10 min.
PE-7: Single-site linear low-density polyethylene composed of ethylene and hexene-1, density = 0.908 g / cm ³ , MFR = 1.0 g / 10 min.

[Example 1]
<Manufacture of medical containers>
Using the polyethylene resin shown in Table 1, a laminated film was formed by a water-cooled coextrusion inflation method. Table 1 shows the thickness of each layer.
Next, the laminated film was heat-sealed, a port was attached, and a medical container having a drug room capacity of 500 mL shown in FIG. 1 was prepared. Thereafter, 500 mL of distilled water was added from the port, sealed with a rubber stopper, and then autoclaved at 105 ° C. for 20 minutes.
The obtained laminated film and medical container were evaluated by the evaluation methods shown below. The results are shown in Table 2.

<Evaluation>
(transparency)
The light transmittance at 450 nm was measured for the medical container after autoclaving.

(Drop bag test)
After high-pressure steam sterilization, it was allowed to stand at 4 ° C. for 24 hours, and then the presence or absence of bag breakage when 5 medical containers were dropped from a height of 2 m was confirmed. The case where all five pieces were not broken was marked with ○, and the case where even one piece was broken was marked with ×.

(Blocking test)
About the laminated film before high-pressure steam sterilization, the blocking property of inner layers and outer layers was evaluated.
The inner layer and the outer layer were overlapped, and a load of 10 kg per 10 cm × 10 cm was applied, left at 50 ° C. for 24 hours, then left at 23 ° C. for 24 hours, then cut out to 10 cm × 10 cm, and speed of 300 mm / min The peel strength was measured.
In the evaluation of the blocking property between the inner layers, when the peel strength is smaller than 5N, the opening property is good, and when it is 5N or more, x is given.
Evaluation of blocking property between outer layers was good when the peel strength was 5N or more, and good stacking property, and x when less than 5N.

[Examples 2-6, Comparative Examples 1-3]
A laminated film and a medical container were prepared and evaluated in the same manner as in Example 1 except that the polyethylene resin used for each layer shown in Table 1 was changed. The results are shown in Table 2.

As is clear from Table 1, all of the medical containers of the examples were excellent in transparency and bag drop strength. Moreover, the inner layers of the laminated film were easily peeled from each other and had good opening properties, while the outer layers were hardly peeled from each other and had good stacking properties.
On the other hand, the medical container of the comparative example did not satisfy all of transparency, bag drop strength, opening property, and stacking property at the same time.

It is a top view which shows an example of the medical container in which one chemical | medical chamber was formed. It is a figure which shows an example of the medical container which carried out stacking, (a) is the side view seen from the port side, (b) is a top view. It is sectional drawing which shows an example of the laminated | multilayer film of this invention. It is a top view which shows an example of the medical container in which two drug rooms were formed.

Explanation of symbols

10: medical container, 11: port, 12: drug room, 13: strong seal part, 14: hanging hole, 20: laminated film, 21: inner layer, 22: middle layer, 23: outer layer, 30: medical container (medical Multi-chamber container), 31: port, 32: chamber, 32a: first chamber, 32b: second chamber, 33: strong seal part, 34: suspension hole, 35: partitioning means.

Claims (6)

A copolymer of an inner layer mainly composed of high-density polyethylene having a melting point of 128 ° C. or higher, ethylene produced with a metallocene catalyst and an α-olefin having 4 or more carbon atoms, and a density of 0.920 g / cm ³ or lower. Characterized in that it is formed of a laminated film comprising an intermediate layer mainly composed of linear low-density polyethylene and an outer layer mainly composed of linear low-density polyethylene having a melting point of 128 ° C. or lower. Medical container. The middle layer is, density 0.900 g / cm ³ or more, polyethylene medical container according to claim 1, characterized in that it contains high-pressure low-density polyethylene is 0.930 g / cm ³ or less. The polyethylene-based polyethylene according to claim 1 or 2, wherein the density of the linear low-density polyethylene that is a main component of the outer layer is 0.900 g / cm ³ or more and 0.925 g / cm ³ or less. Medical container. It said outer layer, density 0.900 g / cm ³ or more, polyethylene according to any one of claims 1 to 3, characterized by containing a high-pressure low-density polyethylene is 0.930 g / cm ³ or less Medical container.   The polyethylene according to any one of claims 1 to 4, wherein the polyethylene has two or more chambers for storing a chemical solution, and each chamber is separated by an easily peelable partition seal. Medical container. A copolymer of an inner layer mainly composed of high-density polyethylene having a melting point of 128 ° C. or higher, ethylene produced with a metallocene catalyst and an α-olefin having 4 or more carbon atoms, and a density of 0.920 g / cm ³ or lower. A polyethylene-based medical comprising an intermediate layer mainly composed of linear low-density polyethylene and an outer layer mainly composed of linear low-density polyethylene having a melting point of 128 ° C. or lower. Laminated film for containers.

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