WO2007102336A1

WO2007102336A1 - Multilayer film and container

Info

Publication number: WO2007102336A1
Application number: PCT/JP2007/053597
Authority: WO
Inventors: Fujio Inoue; Isamu Tateishi
Original assignee: Otsuka Pharmaceutical Factory, Inc.
Priority date: 2006-03-03
Filing date: 2007-02-27
Publication date: 2007-09-13
Also published as: TW200740608A; JP4933529B2; JPWO2007102336A1

Abstract

Disclosed is a multilayer film excellent in heat resistance, sealing strength, transparency, moisture impermeability and flexibility. Also disclosed is a container. Specifically disclosed is a multilayer film comprising five layers mainly composed of an ethylene/α-olefin copolymer. The densities of the first layer and the third layer are both more than 0.950 g/cm3 but not more than 0.970 g/cm3; or alternatively, the density of the first layer is 0.0935-0.950 g/cm3 and the density of the third layer is more than 0.950 g/cm3 but not more than 0.970 g/cm3, or the density of the first layer is more than 0.950 g/cm3 but not more than 0.970 g/cm3 and the density of the third layer is 0.925-0.950 g/cm3. The densities of the second layer and the fourth layer are both not more than 0.920 g/cm3, and the density of the fifth layer is 0.925-0.940 g/cm3. A container (16) is formed by using this multilayer film (10) in such a manner that the first layer serves as an outer layer (17) of the container and the fifth layer serves as an inner layer (18) of the container.

Description

Specification

Multilayer film and container

Technical field

[0001] The present invention relates to a multilayer film and a container formed using the same, and more particularly to a multilayer film and a container used in a medical field for containing a drug solution, blood and the like.

Background art

[0002] Conventionally, containers made of polyethylene-based resin have been known as a container having a multilayer film force for medical use (see Patent Documents 1 to 4).

Patent Document 1: From a laminate in which the copolymer strength of ethylene and 1-olefin is also present, and the inner and outer layers have a resin density of 0.920 gZcm ³ or more and the intermediate layer has a resin density of less than 0.920 gZcm ³ . Become a medical bag.

[0003] Patent Document 2: Consists of linear low-density polyethylene that is a copolymer force of ethylene and a-olefin. The inner layer and outer layer have a density of 0.910-0.940gZcm ³ and the intermediate layer has a density of 0. 880-0. in 905gZcm ^3, the inner and outer layers and least be 0. OlgZcm ³ plastic container having a density difference between the intermediate layer.

Patent Document 3: A branched low-density polyethylene with a density of 0.918 gZcm ³ or more obtained by the high-pressure method for the inner layer, and a straight chain in which the intermediate layer is a copolymer of ethylene and 1-olefin with a density of 0.915 gZcm ³ or less A medical fluid bag having a low-density polyethylene and a laminated low-density polyethylene whose outer layer is a linear low-density polyethylene having a density of 0.920 gZcm ³ or more.

[0004] Patent Document 4: is the force of bag such as a multilayer film consisting of three or more layers, the low density polyethylene榭脂the inner and outer layers is obtained by density 0. 9 30gZcm ³ following radical polymerization method, density 0. 945GZcm and ^three or more MwZMn consists 4.0 or less high density polyethylene榭脂a 5-4 0% containing composition, linear low density intermediate layer has a short chain branching of less density 0. 920 g / cm ³ A medical bag having a composition strength containing at least 15% of a high-density polyethylene resin having a density of 0.945 gZcm ³ or more and MwZMn of 4.0 or less in a polyethylene copolymer. [0005] Further, Patent Document 5 discloses a five-layer film having ethylene'a-olefin copolymer power, and the density of the resin constituting each layer is, in order from the outer layer, the first layer: 0.953- 950g / cm ³ , 2nd layer: 0.920gZcm ³ or less, 3rd layer: 0.925 ~ 0.950g / cm ³ , 4th layer: 0.920gZcm ³ or less, 5th layer: 0.925 -0. A multilayer film of 940 gZcm ³ has been proposed.

Patent Document 1: Japanese Patent Laid-Open No. 62-64363

Patent Document 2: Japanese Patent Laid-Open No. 63-248633

Patent Document 3: Japanese Patent Laid-Open No. 3-277365

Patent Document 4: Japanese Patent Laid-Open No. 4-266759

Patent Document 5: Pamphlet of International Publication No. 95Z22456

Disclosure of the invention

Problems to be solved by the invention

[0006] However, the container having a three-layer film force described in Patent Documents 1 to 4, for example, has a relatively low density of the entire film, so that the heat resistance is not sufficient. When the high-temperature sterilization treatment such as, the seal strength is reduced, the seal part is peeled off by the impact of dropping (drop strength is reduced), and the transparency and moisture permeability are reduced. Problems are likely to occur.

[0007] Further, for example, when the container is formed because the mechanical strength (for example, tensile strength) of the multilayer film is not sufficient, the thickness of the multilayer film is reduced (the amount of resin used is reduced). However, it is difficult to reduce the manufacturing cost, and it is difficult to achieve both the mechanical strength and flexibility of the container.

On the other hand, according to the container having a five-layer film force described in Patent Document 5, the above-mentioned problems can be almost eliminated, but after performing high-temperature sterilization treatment such as high-pressure steam sterilization or hot water sterilization, for example. It was difficult to reduce the thickness of the multilayer film (thin wall) while maintaining the drop strength, transparency, and moisture permeability of the film.

The object of the present invention is to provide a multilayer film excellent in heat resistance, sealing strength, transparency, moisture permeability and flexibility, and heat resistance, drop strength, transparency, moisture permeability and flexibility, and multilayer It is to provide a container capable of thinning a film. Means for solving the problem

[0009] To achieve the above object, the multilayer film of the present invention includes a first layer, a second layer stacked on the first layer, a third layer stacked on the second layer, A fourth layer laminated on the third layer; and a fifth layer laminated on the fourth layer, wherein the first layer and the third layer are made of ethylene 'a-olefin copolymer and Z or polyethylene homopolymer. A polymer, wherein the second layer, the fourth layer, and the fifth layer include an ethylene'a one-year-old refin copolymer, and the density of the first layer and the third layer is

(A) both exceeded ^{0. 950g / cm 3 0. 970g /} cm 3 or less,

(B) The first layer is 0.935 g / cm ³ or more and 0.950 g / cm ³ or less, and the third layer is more than 0.950 g / cm ³ or 970 gZcm ³ or less, or

(C) in the first layer exceeds the ^{0. 950g / cm 3 0. 970g /} cm 3 or less, and a third layer 0. 925 g / cm ³ or more 0. 950GZcm ³ or less,

The density of the second layer and the fourth layer are both 0.920 g / cm ³ or less, and the density of the fifth layer is 0.925 g / cm ³ or more and 0.940 g / cm ³ or less. It is said.

According to the multilayer film of the present invention, at least one of the first layer and the third layer has an ethylene α-olefin having a density of more than 0.950 gZcm ³ and not more than 0.970 gZcm ³ Since it contains a copolymer and cocoon or polyethylene homopolymer, it can exhibit excellent heat resistance, sealing strength, transparency, moisture permeability and flexibility for multilayer films.

[0011] Further, the multilayer film of the present invention,

(1) that the density of the first layer and the third layer is, are both greater than ^{0. 950g / cm 3 0. 970g /} cm 3 or less,

(2) density of the first layer, 0. 935GZcm ³ or more 0. 950GZcm ³ below, the density of the third layer, it is 0. 970GZcm ³ below exceed the 0. 950GZcm ^3, or,

(3) density of the first layer is at 0. 970GZcm ³ below exceed the 0. 950GZcm ^3, density before Symbol third layer that is 0. 925GZcm ³ or 0. 950GZcm ³ or less, is preferred It is.

In preferred embodiments shown in the above (1) to (3), an ethylene 'a-olefin copolymer and Z Or comprises a polyethylene homopolymer, and the force density is provided only on either the first layer or the third layer layer strength is 0. 9 70gZcm ³ below exceed the 0. 950GZcm ^3, it was or, first It is provided in both the third layer and the third layer, and this makes it possible to impart excellent heat resistance, sealing strength, transparency, moisture impermeability and flexibility to the multilayer film.

[0013] In the multilayer film of the present invention, the ratio of the thickness of each layer is such that the first layer is 5 to 15% of the total thickness, and the second layer is 15 to 45% of the total thickness. The third layer is 3 to 40% of the total thickness, the fourth layer is 15 to 45% of the total thickness, and the fifth layer force is 5 to 20% of the total thickness. Is preferred.

According to the above preferred embodiment, the ratio of the thickness of each layer is set within the above range, thereby improving the heat resistance, seal strength, transparency, moisture permeability and flexibility of the multilayer film in a balanced manner. Can do.

[0014] The multilayer film of the present invention preferably has a total thickness of 220 µm or less.

In this case, the multilayer film can be thinned and the manufacturing cost can be reduced while maintaining the heat resistance, sealing strength, transparency, moisture permeability and flexibility of the multilayer film.

The container of the present invention includes a first layer, a second layer stacked on the first layer, a third layer stacked on the second layer, a fourth layer stacked on the third layer, A fifth layer laminated on the fourth layer, wherein the first layer and the third layer include ethylene'a one-year-old refin copolymer and Z or polyethylene homopolymer, and the second layer, the fourth layer The layer and the fifth layer comprise an ethylene 'a olefin copolymer, and the density of the first layer and the third layer is

(A) both exceeded ^{0. 950g / cm 3 0. 970g /} cm 3 or less,

(C) a first layer forces SO. 950 g / cm ³ at a greater than 0. 970 g / cm ³ or less, and a third layer forces 0. 925 g / cm ³ or more 0. 950GZcm ³ or less,

From the multilayer film in which the density of both the second layer and the fourth layer is 0.920 g / cm ³ or less, and the density of the fifth layer is 0.925 gZcm ³ or more and 0.940 gZcm ³ or less. The layer is an outer layer, and the fifth layer is an inner layer. [0015] According to the container of the present invention, it is excellent in heat resistance, drop strength, transparency, moisture permeability, flexibility, etc., and when the multilayer film is thinned and subjected to high-temperature sterilization treatment. However, the above characteristics can be maintained.

The container of the present invention is

[0016] In a preferred embodiment shown in the above (1) to (3), ethylene 'a Orefuin copolymer and includes a Z or polyethylene homopolymers, and density, 0. 9 70gZcm ³ below exceed the 0. 950GZcm ³ The laminar force is the force provided only in either the first layer or the third layer, or is provided in both the first layer and the third layer. Excellent heat resistance, drop strength, transparency, moisture permeability and flexibility can be imparted.

The invention's effect

[0017] According to the multilayer film and container of the present invention, excellent heat resistance, seal strength (drop strength), transparency, moisture permeability and flexibility can be exhibited, and the multilayer film can be thinned. Can do. In addition, for example, it can be suitably used in applications such as medical containers that require high-temperature sterilization.

Brief Description of Drawings

FIG. 1 is a schematic configuration diagram showing a layer configuration of a multilayer film of the present invention.

[FIG. 2] FIG. 2 (a) is a front view showing an embodiment of the container of the present invention, and FIG. 2 (b) is a schematic cross-sectional view showing the layer structure of the multilayer film in part A of FIG. It is.

FIG. 3 is a front view showing another embodiment of the container of the present invention. Explanation of symbols

[0019] 10 multilayer film

11 Layer 1

12 Layer 2

13 Layer 3

14 Layer 4

15 5th layer

16 containers (single chamber bag)

17 outer layer

18 Inner layer

22 containers (multi-chamber bag)

Embodiments of the Invention

FIG. 1 is a schematic configuration diagram showing a layer configuration of the multilayer film of the present invention. Hereinafter, the multilayer film of the present invention will be described with reference to FIG.

In FIG. 1, the multilayer film 10 includes a first layer 11 and a second layer 1 laminated on the first layer 11.

2, the third layer 13 stacked on the second layer 12, the fourth layer 14 stacked on the third layer 13, and the fourth layer 1

And a fifth layer 15 laminated on 4.

[0021] The first layer 11 is a layer disposed on one surface of the multilayer film 10, and forms an outer layer in a container described later.

Since the first layer 11 is a layer that forms an outer layer in a container described later, sufficient mechanical strength (particularly tensile strength) and excellent heat resistance are required.

榭脂forming the first layer 11 is an ethylene 'a- Orefuin copolymer and / or port re ethylene homopolymer (i.e., ethylene. _A Orefuin copolymer, polyethylene homopolymer, and ethylene' a Orefuin copolymer Or a mixed resin of polyethylene homopolymer).

[0022] The α-olefin of the ethylene 'a-olefin copolymer includes, for example, propylene,

1-butene, 1-pentene, 1-hexene, 4-methyl 1-pentene, 1-heptene, 1

—Otaten, 1-nonene, 1-decene, 1-undecene, 1-dodecene, etc. 3 to 1 carbon atoms 2 a-olefins may be mentioned, and these may be used alone or in combination of two or more. Of the above a-olefins, propylene is preferable.

[0023] The ethylene'a-olefin copolymer may be a mixture of two or more different ethylene'α-olefin copolymers.

Further, the resin forming the first layer 11 may contain, for example, ethylene'a-olefin-based elastomer in addition to ethylene'a-olefin copolymer and polyethylene homopolymer.

[0024] The resin forming the first layer 11 is preferably composed of ethylene'a 1-year-old refin copolymer and Z or polyethylene homopolymer.

In addition, the resin forming the first layer 11 is preferably linear, for example, from the viewpoint of maintaining the transparency of the entire multilayer film 10.

The melt flow rate (MFR) of the resin forming the first layer 11 is preferably 1.5 to 2.5 gZlO (190 ° C), and the melting point is preferably 120 to 130 ° C. It is.

[0025] The density of the ethylene'a-olefin copolymer, polyethylene homopolymer and the like forming the first layer 11 is not particularly limited, and may be a range in which the density of the first layer 11 can be set within the following density range. Can be selected as appropriate. That is, the density of the ethylene 'a-olefin copolymer, polyethylene homopolymer, etc. may be within the density range of the first layer 11 described later, and the ethylene' a-olefin copolymer, polyethylene homopolymer, etc. When the density of the mixed resin as the component force is within the density range of the first layer 11 described later, the density of each component forming the first layer 11 is out of the density range of the first layer 11 described later. May be.

[0026] Density of the first layer 11, except where 0. 950 g / cm ³ and greater than 0. 970 g / cm ³ or less is the force, or the density of the third layer to be described later is 0. 950GZcm ³ below , it is less than or equal to 0. 935gZcm ³ or more on 0. 950gZcm ^3.

Further, in the case where the first layer 11 is less than 0. 970gZcm ³ exceeds the density force 0. 950gZcm ^3, more preferred density range is 0. 960 g / cm ³ or less greater than 0. 950g / cm ^3. On the other hand, when the density force of the first layer 11 is 0.935 gZcm ³ or more and 0.950 gZcm ³ or less. In this case, a more preferable density range is 0.935 gZcm ³ or more and 0.945 gZcm ³ or less.

[0027] The first layer 11 is preferably

(i) a force comprising an ethylene 'a-olefin copolymer and a density of 0.935 gZcm ³ or more and 0.950 gZ cm' or less,

(ii) Consisting of ethylene 'a-olefin copolymer and polyethylene homopolymer (hereinafter referred to as "mixed resin of ethylene' a-olefin copolymer and polyethylene homopolymer"), with a density of at least 0.935 gZcm ³ 0. 950gZcm ³ or less,

(iii) ethylene 'a Orefuin copolymer and mixtures榭脂or Rannahli of polyethylene homopolymer, force density of 0. 970gZcm ³ below exceed the 0. 950gZcm ³ or,

(iv) it consists of polyethylene homopolymer, density of 0. 970gZ cm ³ or less greater than 0. 950gZcm ^3.

[0028] The first layer 11 is more preferably represented by the above (i) or (ii). However, the above (i) or (ii) is selected only when the density of the third layer 13 to be described later exceeds 0.950 g / cm ³ .

The resin forming the first layer 11 may be the same as or different from the resin forming the third layer 13 described later.

[0029] The thickness of the first layer 11 is preferably 5 to 15% with respect to the total thickness of the multilayer film 10. The second layer 12 is an intermediate layer of the multilayer film 10, and It is arranged between the third layer 13 described later.

The second layer 12 is required to have a relatively low density from the viewpoint of imparting high flexibility to the container described later.

[0030] The resin forming the second layer 12 contains an ethylene'a-olefin copolymer.

Examples of the a-olefin used in the ethylene 'a-olefin copolymer include the same ones as described above, and propylene is preferable.

The ethylene 'a-olefin copolymer may be a mixture of two or more different ethylene' α-olefin copolymers. [0031] Further, the resin forming the second layer 12 may contain, for example, an ethylene- _a- olefin-based elastomer, a high-density polyethylene homopolymer, or the like in addition to the ethylene'a-olefin copolymer. Good.

It is preferable that the resin forming the second layer 12 also has an ethylene'a-olefin copolymer strength.

In addition, the resin forming the second layer 12 is preferably linear, for example, from the viewpoint of maintaining the transparency of the entire multilayer film 10.

The MFR of the resin forming the second layer 12 is preferably 0.5 to 4. OgZlO (190 ° C), and the melting point is preferably 105 to 120 ° C.

The density of the ethylene ′ a-olefin copolymer forming the second layer 12 is not particularly limited, and may be appropriately selected as long as the density of the second layer 12 can be set within the following density range. it can. That is, the density of the ethylene'a-olefin copolymer and the like may be within the density range of the second layer 12 described later, and the density of the mixed resin that also has component power such as the ethylene'a-olefin copolymer, When the density is within the density range of the second layer 12 described later, the density of each component forming the second layer 12 may be out of the density range of the second layer 12 described later.

The density of the second layer 12 is 0.920 g / cm ³ or less, preferably 0.990 g / cm ³ or more and 0.920 gZcm ³ or less, more preferably 0.990 gZcm ³ or more and 0.905 gZcm ³ or less. It is. The second layer 12 preferably also has an ethylene ′ a-olefin copolymer strength and has a density of 0.92 OgZcm ³ or less.

[0034] The resin forming the second layer 12 may be, for example, a mixed resin shown in the following (a) to (c).

(a) Density is 0. 900gZcm ³ or 0. 920gZcm ³ following ethylene · alpha-Orefuin copolymer containing 40 to 60 weight ^_0/0, ethylene density less than 0. 900gZcm ³ 'α- Orefu in system elastomer scratch 40-60 weight ^_0/0 contains, further, the density contains less than 5% by weight of 0. 955g / cm ³ or more high-density polyethylene, the overall density of 0. 920gZcm ³ following mixed-榭脂(Ethylene · _a 1 year old refin copolymer).

(b) Ethylene 'α-olefin with a density of 0.900 gZcm ³ or more and 0.920 gZcm ³ or less The polymer 20 to 60 wt% (preferably 40 to 60 wt%) containing a density 0. 900 g / cm ³ less than the ethylene 'at- Orefuin elastomers scratch contain 40 to 60 weight ^_0/0, Furthermore, the density is 0. 935gZcm ³ or 0. 945gZcm ³ following ethylene 'alpha-the Orefuin copolymer 30 wt% or less (preferably 20 wt% or less) containing the density of the total 0. 920 g ZCM ³ below Mixed rosin (ethylene'a one-year-old refin copolymer).

(c) density of 0. 935gZcm ³ or 0. 945gZcm ³ following ethylene · alpha-Orefuin copolymer containing 20 to 50 weight ^_0/0, ethylene density less than 0. 900gZcm ³ 'α- Orefu in system A mixed resin containing 50 to 80 weight percent of elastomer and having an overall density of 0.920 g / cm ³ or less (ethylene / _a one-year-old refin copolymer).

[0035] Examples of the α-olefin used in the ethylene-a-olefin-elastomer include those described above.

The resin forming the second layer 12 may be the same as or different from the resin forming the fourth layer 14 described later.

The thickness of the second layer 12 is preferably 15 to 45%, more preferably 15 to 30% with respect to the total thickness of the multilayer film 10.

[0036] The third layer 13 is an intermediate layer of the multilayer film 10, and is disposed opposite to the first layer 11 with the second layer 12 interposed therebetween.

This third layer 13 is required to have excellent mechanical strength from the viewpoint of imparting sufficient strength (waist) to the container described later.

榭脂forming the third layer 13 is an ethylene 'a one year old Refuin copolymer and Z or Po Li ethylene homopolymer (ethylene. _A Orefuin copolymer, polyethylene homopolymer one, and ethylene' a Orefuin copolymer And mixed with polyethylene homopolymer).

[0037] Examples of the α-olefin of the ethylene'-olefin copolymer include the same as those described above, and propylene is preferable.

The ethylene 'a-olefin copolymer may be a mixture of two or more different ethylene' α-olefin copolymers.

Further, the resin forming the third layer 13 is composed of ethylene'a-olefin copolymer and polyethylene. In addition to the tylene homopolymer, it may contain, for example, ethylene a-olefin elastomer.

[0038] The resin forming the third layer 13 is preferably made of ethylene 'a-olefin copolymer and Z or polyethylene homopolymer.

In addition, the resin forming the third layer 13 is preferably linear, for example, from the viewpoint of maintaining the transparency of the entire multilayer film 10.

The MFR of the resin forming the third layer 13 is preferably 1.5 to 2.5 gZlO (190 ° C), and the melting point is preferably 120 to 130 ° C.

[0039] The density of the ethylene 'α-olefin copolymer, polyethylene homopolymer, etc. forming the third layer 13 is not particularly limited, and may be a range in which the density of the third layer 13 can be set within the following density range. Can be selected as appropriate. That is, the density of ethylene'a-olefin copolymer, polyethylene homopolymer, etc. may be within the density range of the third layer 13 described later, and the density of ethylene'a-olefin copolymer, polyethylene homopolymer, etc. When the density of the mixed resin that also has component power is within the density range of the third layer 13 described later, the density of each component forming the third layer 13 is out of the density range of the third layer 13 described later. May be.

[0040] Density of the third layer 13 is 0. 970GZcm ³ below exceed the 0. 950GZcm ³ force, or, unless the density of the first layer is 0. 950GZcm ³ below, 0. 925GZcm ³ more than 0. 950gZcm is ³ or less.

The density of the third layer 13, in the case where 0. 970GZcm ³ below exceed the 0. 950GZcm ^3, more preferably the density range is 0. 960 g / cm ³ or less greater than 0. 950 g / cm ^3. On the other hand, when the density of the third layer 13 is 0.925 gZcm ³ or more and 0.950 gZcm ³ or less, a more preferable density range is 0.930 gZcm ³ or more and 0.940 gZcm ³ or less.

[0041] The third layer 13 is preferably

(I) a force comprising an ethylene 'a-olefin copolymer and having a density of not less than 0.925 gZcm ^{3 and not} more than 0.950 / cm',

(II) Is it a mixed resin of ethylene 'a-olefin copolymer and polyethylene homopolymer? The density is not less than 0.925 gZcm ^{3 and not} more than 0.950 gZcm ³ ,

(IV) consists of polyethylene homopolymer, density of 0. 970gZ cm ³ or less greater than 0. 950gZcm ^3.

[0042] The third layer 13 is more preferably represented by the above (III) or (IV). The above (I) or (または) is selected only when the density of the first layer 11 exceeds 0.950 g / cm ³ . The resin forming the third layer 13 may be the same as or different from the resin forming the first layer 11.

[0043] The thickness of the third layer 13 is preferably 3 to 40%, more preferably 15 to 30%, based on the total thickness of the multilayer film 10.

The fourth layer 14 is an intermediate layer of the multilayer film 10 and is disposed opposite to the second layer with the third layer interposed therebetween.

The fourth layer 14 is required to have a relatively low density from the viewpoint of imparting high flexibility to the container described later.

[0044] The resin forming the fourth layer 14 contains an ethylene'a-olefin copolymer.

[0045] Further,榭脂forming a fourth layer 14, in addition to ethylene 'a- Orefuin copolymers, For example, ethylene. _A Orefuin elastomers mono-, also contain high-density polyethylene homopolymer Good.

It is preferable that the resin forming the fourth layer 14 also has an ethylene'a-olefin copolymer strength.

In addition, the resin forming the fourth layer is preferably linear, for example, from the viewpoint of maintaining the transparency of the entire multilayer film 10.

The MFR of the resin forming the fourth layer 14 is preferably 0.5 to 4. OgZlO content (190 ° C) and the melting point is preferably 105-120 ° C.

The density of the ethylene'a-olefin copolymer forming the fourth layer 14 is not particularly limited, and may be appropriately selected as long as the density of the fourth layer 14 can be set within the following density range. it can. That is, the density of the ethylene 'a-olefin copolymer or the like may be within the density range of the fourth layer 14 to be described later, and the density of the mixed resin that also has component power, such as the ethylene' a-olefin copolymer, When the density is within the density range of the fourth layer 14 described later, the density of each component forming the fourth layer 14 may be outside the density range of the fourth layer 14 described later.

The density of the fourth layer 14 is 0.920 g / cm ³ or less, preferably 0.990 g / cm ³ or more and 0.920 gZcm ³ or less, more preferably 0.990 gZcm ³ or more and 0.905 gZcm ³ or less. It is.

The fourth layer 14 preferably also has an ethylene'a-olefin copolymer power and has a density of 0.92 OgZcm ³ or less.

[0048] The resin forming the fourth layer 14 may be, for example, the mixed resin shown in the above (a) to (c) exemplified as the resin forming the second layer 12! ,.

Examples of the a-olefin of the ethylene-a-olefin elastomer include the same ones as described above.

The resin forming the fourth layer 14 may be the same as or different from the resin forming the second layer 12.

[0049] The thickness of the fourth layer 14 is preferably 15 to 45%, more preferably 15 to 35% with respect to the total thickness of the multilayer film 10.

The fifth layer 15 is a layer disposed on the other surface of the multilayer film 10 and forms an inner layer in the container described later.

Since the fifth layer 15 is a layer that forms an inner layer in a container described later, it is excellent from the viewpoint that it can withstand sterilization under high temperature conditions, does not cause blocking, and can be easily welded. Blocking resistance and heat resistance are required.

[0050] The resin forming the fifth layer 15 contains an ethylene 'a-olefin copolymer.

Examples of the a-olefin used in the ethylene 'a-olefin copolymer include the same ones as described above, and propylene is preferable. The ethylene 'a-olefin copolymer may be a mixture of two or more different ethylene' α-olefin copolymers.

[0051] The resin forming the fifth layer 15 may contain, for example, ethylene. A-olefin-based elastomer, polyethylene homopolymer, etc., in addition to the ethylene'- _a- olefin copolymer.

It is preferable that the resin forming the fifth layer 15 also has an ethylene'a-olefin copolymer strength.

[0052] The resin forming the fifth layer 15 is preferably linear, for example, from the viewpoint of maintaining the transparency of the entire multilayer film 10.

The MFR of the resin forming the fifth layer 15 is preferably 1.5 to 2.5 gZlO (190 ° C), and the melting point is preferably 120 to 130 ° C.

The density of the ethylene 'a-olefin copolymer forming the fifth layer 15 is not particularly limited, and may be appropriately selected as long as the density of the fifth layer 15 can be set within the following density range. it can. That is, the density of ethylene'a-olefin copolymer and the like may be within the density range of the fifth layer 15 described later, and the density of the mixed resin that also has component power such as ethylene'a-olefin copolymer, When the density is within the density range of the fifth layer 15 described later, the density of each component forming the fifth layer 15 may be outside the density range of the fifth layer 15 described later.

[0053] The density of the fifth layer 15 is 0.925 g / cm ³ or more and 0.940 g / cm ³ or less, preferably 0.930 gZcm ³ or more and 0.940 gZcm ³ or less.

Also,榭脂forming the fifth layer 15 is, for example, the density is 0. 925gZcm ³ or 0. 940 g / cm ³ or less of ethylene 'a- Orefuin copolymer containing 90 weight ^_0/0 or more, density 0. 9 45gZcm ³ or more ethylene · (X- containing Orefuin copolymer in a proportion of 10 weight ^_0/0 or less, the density of the total 0. 925gZcm ³ or 0. 940gZcm ³ following mixing榭脂(ethylene ' a-olefin copolymer).

[0054] The thickness of the fifth layer 15 is preferably 5 to 20%, more preferably 10 to 20% with respect to the total thickness of the multilayer film 10.

The total thickness of the multilayer film 10 is generally 100 to 300 μm, In addition, it can be appropriately increased or decreased. Among these, the thickness is preferably 220 μm or less, more preferably 160 m or more and less than 200 μm.

[0055] The multilayer film 10 has excellent heat resistance, seal strength, transparency, moisture permeability, and flexibility. For example, when forming a container to be described later, 220 / zm or less, Even if the thickness is 180 to 200 m, sufficient strength can be secured. Although not limited to this, the thickness force of the multilayer film 10 is set to 220 m or less, particularly 160 μm or more and less than 200 μm! In this case, the multilayer film 10 is formed using this multilayer film 10. The containers used are suitable for applications such as infusion bags, blood bags, enteral nutrition bags, and liquid food bags with an internal volume of up to about 500 mL.

[0056] The method for producing the multilayer film 10 is not particularly limited, and examples thereof include a water-cooled or air-cooled coextrusion inflation method, a coextrusion T-die method, a dry lamination method, and an extrusion lamination method. . Of these, the water-cooled coextrusion inflation method and the coextrusion T-die method are preferred from the viewpoints of the characteristics of the multilayer film, particularly transparency, economy in the production of the multilayer film, and hygiene of the multilayer film. It is done.

[0057] In any of the above methods, the production of the multilayer film 10 needs to be performed at a temperature at which the resin forming each layer melts. If the production temperature is too high, a part of the resin is heated. Decomposition may cause degradation of performance due to decomposition products. Therefore, the production temperature of the multilayer film 10 is not limited to this, but is preferably 150 to 250 ° C., more preferably 170 to 200 ° C. In addition, it is preferable that the resin constituting each layer has as little difference in MFR as possible in order to maintain the transparency of the multilayer film 10.

[0058] According to the multilayer film 10 described above, excellent heat resistance, seal strength, transparency, moisture permeability and flexibility can be imparted to the multilayer film. When 10 is thinned, specifically, even when the thickness is set to a small range such as 220 / zm or less, it can be maintained. Therefore, the multilayer film 10 is suitable as a material for forming a container such as a chemical liquid container.

[0059] Fig. 2 (a) is a front view showing an embodiment of the container of the present invention, and Fig. 2 (b) is a schematic cross-sectional view showing the layer structure of the multilayer film in part A of Fig. (A). FIG. 3 is a front view showing another embodiment of the container of the present invention. Hereinafter, the present invention will be described with reference to FIG. 2 and FIG. The container will be described.

2 (a) and 2 (b), the container 16 is formed by forming the first layer 11 of the multilayer film 10 shown in FIG. 1 as the outer layer 17 and the fifth layer 15 as the inner layer 18.

[0060] The container 16 shown in FIGS. 2 (a) and 2 (b) is formed by welding the peripheral portions in a state where two multilayer films 10 are overlapped so that the fifth layers 15 face each other. A seal portion 19 is formed, and a cylindrical member 20 to be welded in a state of being sandwiched between two multilayer films 10 is provided in a part of the seal portion 19.

The container 16 is a single-chamber bag provided with a storage chamber 21 for storing a chemical solution therein.

In FIG. 3, the container 22 is formed with the first layer 11 of the multilayer film 10 shown in FIG. 1 as an outer layer and the fifth layer 15 as an inner layer.

The container 22 shown in FIG. 3 includes a seal portion 19 formed by welding two peripheral films 10 in a state where the multilayer portions 10 are overlapped so that the respective fifth layers face each other. A cylindrical member 20 that is welded in a state of being sandwiched between two multilayer films 10 is provided on a part of the seal portion 19.

[0062] The container 22 is a multi-chamber bag including two storage chambers 23a and 23b for storing a chemical solution therein, and the two storage chambers 23 are separated by an easily peelable seal portion 24. It has been.

The easily peelable seal portion 24 is formed by welding the fifth layers of two multilayer films 10, and the seal strength is determined by pressing one of the two storage chambers 23a and 23b. When the hydraulic pressure from the storage chamber is applied to the easily peelable seal portion 24, it is set to such an extent that it is easily cleaved.

[0063] In the containers 16, 22, the seal portion 19 is formed by, for example, welding the peripheral portion of the multilayer film 10 in a state where the multilayer film 10 is overlapped so that the fifth layer 15 is inside. It can also be formed. Further, the seal portion 19 is formed by forming the multilayer film 10 into a bag shape or a tube shape by an inflation method so that the fifth layer 15 is on the inside, and the bag-shaped or tube-shaped multilayer film 10 thus obtained is formed. It can also be formed by welding the peripheral edge of each. [0064] When the seal part 19 is formed by heat sealing, the heat sealing temperature of the multilayer film 10 is not particularly limited, but is preferably 120 to 160 ° C. Further, when the thickness force of the multilayer film 10 is, for example, about 180 m, the seal portion 19 can be formed by setting the seal time to 0.5 to 5 seconds in the above temperature range.

[0065] The heat sealing condition of the easy-peeling seal portion 24 is not particularly limited, but is preferably 110 to 130 ° C and 0.5 to 5 seconds, for example.

The cylindrical member 20 allows the chemical solution stored in the storage chambers 21 and 23 of the containers 16 and 22 to flow out of the containers 16 and 22, or from the outside of the containers 16 and 22 to the storage chambers 21 and 23. It is a member for injecting chemicals. Usually, a sealing body (for example, a rubber plug or the like) that can be punctured with a hollow needle or the like for sealing the cylindrical member 20 is disposed inside the cylindrical member 20.

[0066] According to the container described above, excellent heat resistance, drop strength, transparency, moisture impermeability and flexibility can be imparted to the container, and the thickness of the multilayer film can be reduced. can do. Therefore, the above container is suitable for use as a chemical container such as an infusion bag.

Example

Next, the power to explain the present invention based on examples and comparative examples The present invention is not limited by the following examples.

Manufacture of multilayer films and containers

The multilayer film 10 shown in FIG. 1 is manufactured by the water-cooled coextrusion inflation method, and then the container (single chamber bag) 16 shown in FIG. 2 is formed using the resulting multilayer film 10 having a total thickness of 180 m. Produced (Examples 1 to 15 and Comparative Examples 1 to 6). The sealing condition of the seal portion 19 of the container 16 was 140 ° C. for 2 seconds, and the storage volume of the storage chamber 21 of the container 16 was 500 mL.

[0068] The resin (PE-1 to PE-12) used for forming the multilayer film 10 is as shown below. In addition, the layer constitution of the multilayer film 10 and the container 16, that is, the type (the density of the resin) and the thickness of the resin used in each layer from the first layer 11 to the fifth layer 15 are shown in Tables 1 to 3 below. It is shown.

• PE-1: Linear medium density polyethylene (ethylene '1-butene copolymer), density 0.935 g MFR = 2. lgZlO content (190.C); mixed fat of PE-4 and PE-11. • PE—2: Linear low-density polyethylene (ethylene '1 -butene copolymer), density 0.905 g Zcm ³ , MFR = 1.2 ₈ 10 min (190, manufactured by Prime Polymer Co., Ltd.)

• PE-3: High density polyethylene (ethylene '1-butene copolymer), density 0.955 g / cm ³ , MFR = 10.5 gZlO (190 ° C); PE-11 and PE-6 mixed grease.

• PE—4: Medium density polyethylene (ethylene '1 -butene copolymer), density 0.930 g / cm ³ , MFR = 2. lgZlO (190 ° C), made by Prime Polymer Co., Ltd.

• PE-5: High density polyethylene (ethylene '1-butene copolymer), density 0.950g / cm ³ , MFR = 4.8gZlO content (190 ° C); PE-6 and PE-11 mixed fat.

• PE-6: High density polyethylene (homopolymer), density 0.965gZcm ³ , MFR = 15g / 10min (190 ° C), made by Prime Polymer Co., Ltd.

• PE—7: Low density polyethylene (ethylene '1 -butene copolymer), density 0.925 g / cm ³ , MFR = 2.3 gZlO content (190 ° C); mixed fat of PE-4 and PE-9 .

• PE—8: Low-density polyethylene (ethylene 1-butene copolymer), density 0.900 g / cm ³ , MFR = 0.9 gZlO (190 ° C), manufactured by Prime Polymer Co., Ltd.

• PE—9: Low density polyethylene (ethylene '1 -butene copolymer), density 0.920 g / cm ³ , MFR = 2. lgZlO (190 ° C), made by Prime Polymer Co., Ltd.

• PE—10: Ethylene 1-butene elastomer, density 0.885gZcm ³ , MFR = 0.5g / 10min (190 ° C), made by Prime Polymer Co., Ltd.

• PE-11: Medium density polyethylene (ethylene 1-butene copolymer), density 0.940 g / cm ³ , MFR = 2.lgZlO (190.C), manufactured by Prime Polymer Co., Ltd.

• PE—12: Low density polyethylene (ethylene '1 butene copolymer), density 0.897 g / cm ³ , MFR = 1. lgZlO content (190.C); PE-6, PE-9 and PE-10 Mixed fat.

Characterization

The following properties of the multilayer film 10 and the container (single chamber bag) 16 obtained in Examples 1 to 13 and Comparative Examples 1 to 6 were evaluated.

(1) Impermeable to moisture

Multilayer film 10 (total thickness 180 m) water vapor permeability is JIS K 7129 plus

-1992 Water vapor permeability test method for tic films and sheets (instrument measurement method) Measured according to the wet sensor method). The model “L80-5000” manufactured by Lissy was used as the measuring instrument. The measurement conditions were 40 ° C and 90% RH.

[0070] Next, based on the measurement results, the moisture permeability of the container 16 formed using the multilayer film 10 and the multilayer film 10 was evaluated.

A: The measurement result was 2.5 gZ (m ² '24h) or less, the water vapor permeability was extremely low, and the moisture permeability was very good.

◯: From the measurement results, moisture permeability was low and water vapor permeability was low.

(Triangle | delta): From the measurement result, the water vapor permeability was somewhat high and the moisture-impermeable property was somewhat poor.

X: From the measurement results, the water vapor permeability was extremely high and the moisture permeability was poor.

[0071] (2) Heat resistance

Container (single chamber bag) 16 storage chambers 21 were filled with distilled water, sealed, and then subjected to high-pressure steam sterilization at 110 ° C for 40 minutes. Next, the container 16 after high-pressure steam sterilization was visually observed for deformation, bag breakage, and seal leakage, and based on the results, the heat resistance of the container 16 was evaluated according to the following criteria.

A: Deformation, bag breakage and seal leakage were not observed at all, and the heat resistance was extremely good. ○: Slight traces of deformation were observed, but no bag breakage or seal leakage was observed, and the heat resistance was good.

Δ: Some deformation, bag breakage or seal leakage was observed, and the heat resistance was somewhat poor from a practical viewpoint.

X: Deformation, bag breakage, or seal leakage was remarkably observed, and the heat resistance was poor.

[0072] (3) Drop strength

Container (single-chamber bag) 16 Filled storage chamber 21 with distilled water, sealed, refrigerated to approximately 4 ° C, and then dropped container 16 into a plane drop (falling in the front direction of container 16) and falling sideways (Dropping of the container 16 in the side direction, that is, falling in the state where the side seal portion 19a is directed downward) and bottom falling (falling of the container 16 in the bottom direction, that is, of the seal portion 19, the cylindrical member 20 The bottom-side seal portion 19b having a bottom surface is dropped in a state where the bottom-side seal portion 19b is faced down), and was dropped from a height of 1.2 m five times for each of the above embodiments. Next, the container 16 after dropping was visually observed for the state of bag breakage and seal leakage. A: No bag breakage or seal leakage was observed, and the drop strength was very good.

○: Although a decrease in the seal strength of the seal part 19 was confirmed, no bag breakage or seal leakage was observed, and the drop strength was good.

Δ: Slightly broken bags and seal leakage were observed, and the drop strength was slightly poor from a practical viewpoint.

X: Deformation, bag breakage, or seal leakage was remarkably observed, and the drop strength was poor.

[0073] (4) Flexibility

The bending strength of the multilayer film 10 was measured using a digital stiffness tester (manufactured by Tester Sangyo Co., Ltd.) in accordance with the provisions of the Paper 'Pulp Technology Association Standard Test (TAPPI) T543.

Next, based on the measurement results, the flexibility of the container 16 formed by using the multilayer film 10 and the multilayer film 10 was evaluated.

A: From the measurement results, the flexibility was extremely good.

◯: From the measurement results, the flexibility was good.

Δ: From the measurement results, the flexibility was slightly poor.

X: The flexibility was poor from the measurement results.

[0074] (5) Transparency

Container (single chamber bag) 16 storage chambers 21 were filled with distilled water, sealed, and then subjected to high-pressure steam sterilization at 110 ° C for 40 minutes. Subsequently, the light transmittance at a wavelength of 450 nm was measured for the container 16 after the high-pressure steam sterilization treatment.

A: The light transmittance at a wavelength of 450 nm is extremely high, and the transparency is very good.

A: The light transmittance at a wavelength of 450 nm is high and the transparency is good.

Δ: Transparency was slightly poor from the practical point of view of a container with low light transmittance at a wavelength of 450 nm.

X: Transparency with very low light transmittance at a wavelength of 450 nm was poor.

[0075] (6) Overall evaluation

In addition to the evaluations in (1) to (5) above, the condition of wrinkles, blocking, deformation, and bag breakage was evaluated by visual observation of the overall appearance of the container (single chamber bag) 16. Physical properties A comprehensive evaluation was made according to the following criteria.

◎: Extremely good

Y: Good

△: Somewhat bad

X: non-people

Tables 1 to 3 show the evaluation results for (1) to (6) above.

[table 1]

[Table 1] S [3] 0072 Outer side inversion ^? Evaluation of physical properties

1st layer 2nd layer 3rd layer 4th layer 5th layer Inertia m Falling 3lUt Flexibility Transparency Evaluation

PE-2

40 m

Example 2 180 ◎ ◎ ◎ ◎ ®

s g * o <n-

o> ¾

180 ◎ ◎ ◎ © oo

0> σ ^ ^

[0078] [Table 3]

[0079] In Table 13 above, the descriptions in the "first layer", "second layer", "third layer", "fourth layer" and "fifth layer" columns are used in the upper row. The serial number of the prepared fat, the middle row indicates the density of the used fat (unit: g Zcm ³ ), and the lower row indicates the layer thickness.

As shown in Table 13, it is clear that the multilayer film and container of the present invention are all excellent in flexibility, heat resistance, strength, and transparency.

[0080] Although the above invention has been provided as an exemplary embodiment of the present invention, this is merely an example. It should only be interpreted in a limited way. Modifications of the present invention apparent to those skilled in the art are included in the invention described in the claims.

Industrial applicability

The multilayer film of the present invention is suitable, for example, as a material for forming a container. Particularly, for example, as a material for forming a container such as a chemical solution bag or an infusion bag that contains a chemical solution and is subjected to sterilization under high temperature conditions. Is preferable.

In addition, the container of the present invention is suitable as a container such as a chemical solution bag or an infusion bag that contains a chemical solution and is subjected to sterilization under high temperature conditions.

Claims

The scope of the claims

[1] A first layer, a second layer stacked on the first layer, a third layer stacked on the second layer, a fourth layer stacked on the third layer, and the fourth layer A fifth layer laminated to the layer,

The first layer and the third layer comprise ethylene 'a-olefin copolymer and Z or polyethylene homopolymer;

The second layer, the fourth layer, and the fifth layer include ethylene'a one-year-old refin copolymer, and the density of the first layer and the third layer is:

(A) both exceeded ^{0. 950g / cm 3 0. 970g /} cm 3 or less,

The density of the second layer and the fourth layer are both 0.920 gZcm ³ or less,

The density of the fifth layer is 0.925 gZcm ³ or more and 0.940 gZcm ³ or less.

A multilayer film characterized by that.

[2] the density of the first layer and the third layer, and characterized in that both greater than 0. 950gZcm ^³ 0. 970g / cm ³ or less, the multilayer film according to claim 1.

[3] The density of the first layer is 0.935 gZcm ³ or more and 0.950 gZcm ³ or less, and the density of the third layer is more than 0.950 gZcm ³ and 0.970 gZcm ³ or less. The multilayer film according to claim 1.

[4] The density of the first layer is more than 0.950 gZcm ³ and not more than 0.970 gZcm ³ ,

The multilayer film according to claim 1, wherein the density of the three layers is 0.925 gZcm ³ or more and 0.950 gZcm ³ or less.

[5] The ratio of the thickness of each layer is such that the first layer is 5 to 15% of the total thickness, and the second layer is

15 to 45% of the total thickness, the third layer is 3 to 40% of the total thickness, the fourth layer force is 15 to 45% of the total thickness, and the fifth layer is the total thickness. The multilayer film according to claim 1, wherein the content is 5 to 20%.

6. The multilayer film according to claim 1, wherein the total thickness is 220 μm or less.

[7] A first layer, a second layer stacked on the first layer, a third layer stacked on the second layer, a fourth layer stacked on the third layer, and the fourth layer A fifth layer laminated to the layer,

(A) both exceeded ^{0. 950g / cm 3 0. 970g /} cm 3 or less,

From the multilayer film, wherein the density of the fifth layer is 0.925 gZcm ³ or more and 0.940 gZcm ³ or less,

The container, wherein the first layer is an outer layer and the fifth layer is an inner layer.

[8] the density of the first layer and the third layer, and characterized in that both greater than 0. 950gZcm ^³ 0. 970g / cm ³ or less, the container according to claim 7.

[9] The density of the first layer is 0.935 gZcm ³ or more and 0.950 gZcm ³ or less, and the density of the third layer is more than 0.950 gZcm ³ and 0.970 gZcm ³ or less. The container according to claim 7.

[10] the density of the first layer can, greater than ^{0. 950g / cm 3 0. 970g /} cm 3 or less, the density of the third layer is 0. 925GZcm ³ or 0. 950GZcm ³ below A container according to claim 7, characterized by: