JPH0752304A - Packaging material excellent in chemical resistance - Google Patents

Abstract

PURPOSE:To obtain a packaging material of a good tearing property without bringing about peeling of a gas barrier layer or the like for various chemicals by a method wherein a heat sealing resin layer is laminated on one surface of the gas barrier layer via a heat melt resin layer and a base material is respectively laminated on the other surface thereof via a tearing film layer. CONSTITUTION:A packaging material is constituted by laminating a heat sealing resin layer on one side surface of a gas barrier layer via a heat melt resin layer and laminating a base material on the other side surface via a tearing film layer. By laminating thus the gas barrier layer between the heat sealing resin layer and the tearing film layer, a high barrier property is obtained. Further, since bonding strength between an adjacent layer and the tearing film layer is prevented from being decreased by permeation of contents, a good tearing property can be obtained irrespective of a kind of the contents. Furthermore, by using the heat melt resin layer for lamination on the more inner layer side than the gas barrier layer, peeling caused by using an adhesive can be prevented from occurring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging material having excellent chemical resistance, which is used for a container for various chemicals such as a photographic developing solution, and more particularly to a packaging material having a function of tearing by hand.

[0002]

2. Description of the Related Art In general, packaging materials used for various containers are often selected with an emphasis on having barrier properties with respect to contents, and particularly for contents such as foods, preservation of the contents. Not only is a high barrier layer used, including barrier properties against oxygen and water vapor. As such a barrier layer, generally, a metal foil such as aluminum, a polyvinylidene chloride-coated resin film, a film obtained by vapor deposition of an inorganic substance such as silicon oxide, or the like is used, and these are usually laminated with an adhesive. there were.

Conventionally, there is a packaging material provided with a tearable film layer in order to provide a container for refilling foods or liquid detergents with a function of tearing by hand, and this tearable film layer is also provided. It was laminated using an adhesive.

However, when such a packaging material is used, the resistance to the organic solvent contained in the content of the barrier layer and the resistance of the content to PH have not been particularly taken into consideration. In addition, even if the pH of the contents is acidic or alkaline, its value is limited in advance, so it is possible to design and use a packaging material that uses a barrier layer that matches this value. Met.

[0005]

However, when applying these packaging materials to various chemicals, etc.,
That is, when the PH value can vary widely from the acidic range to the alkaline range, a packaging material that can be applied only to a specific PH range is insufficient. In particular, the volatile components of the contents stay between the layers, resulting in undesirable phenomena such as attacking the adhesive and corroding metals such as aluminum, or causing peeling between layers and degrading tearability. Was causing problems.

That is, an object of the present invention is to provide a packaging material having excellent gas barrier properties against various chemicals without causing peeling of the gas barrier layer and the like, and having good tearability. is there.

[0007]

In order to achieve the above object, the packaging material of the present invention has a heat-sealing resin layer laminated on one surface of a gas barrier layer via a heat-melting resin layer,
It is characterized in that a base material is laminated on the other surface via a tearable film layer.

The gas barrier layer is made of ethylene-
It is characterized by comprising a coextruded film having a saponified vinyl acetate copolymer layer and a nylon layer provided on both sides thereof.

The gas barrier layer has SiOx (x is 1 to 1) on at least one surface of the plastic film.
It is characterized by having a vapor deposition layer of 2).

Further, the invention is characterized in that the gas barrier layer and the tearable film layer are laminated by interposing a hot melt resin layer or by a dry lamination method.

Further, a high-density polyethylene layer is provided on the gas barrier layer via a hot-melt resin layer, and a heat-sealing resin layer is further laminated on the high-density polyethylene layer via the hot-melt resin layer. It is characterized by

The present invention will be described in more detail below.

The gas barrier layer in the present invention is, for example,
Saponified ethylene-vinyl acetate copolymer (hereinafter EVOH
A layer having a nylon (hereinafter referred to as Ny) layer on both sides of a layer, which is obtained by coextrusion, but is preferably a linear low density polyethylene (hereinafter referred to as LLDPE) on at least one Ny layer. (Hereinafter referred to as)), such as Ny / EVOH / Ny / LLDPE, LLDPE / Ny / EVOH / Ny / LLDPE, and the like.

As another constitutional example of the gas barrier layer in the present invention, SiO _x (x is 1 to 1) on at least one surface of a plastic film such as polyester resin.
The vapor deposition layer of 2) is formed. As the plastic film, nylon, stretched polyvinyl alcohol, stretched polypropylene, polyethylene terephthalate (PE
T) is preferably used. Further, the thickness of the vapor deposition layer of SiO _X is preferably 200 to 1000Å.

When the above gas barrier layer has a vapor-deposited layer of SiO _x on only one surface of the plastic film, when this is used as a packaging material, SiO _x is used.
It is necessary to make the vapor-deposited layer on the inside. This is because the adhesive strength between the PET and the vapor-deposited layer of SiO _x may be lowered due to the influence of the contents.

The packaging material of the present invention is formed by laminating a heat-sealable resin layer such as LLDPE on the above gas barrier layer via a hot-melt resin layer such as polyethylene or acid-modified polyethylene. Further, in the present invention, a high-density polyethylene (hereinafter referred to as HDPE) layer is provided between the gas barrier layer and the heat-sealable resin layer via the same hot-melt resin layer as described above to impart rigidity as a packaging material. Configuration, for example, substrate /.../ (LLDPE) /
Ny / EVOH / Ny / LLDPE / PE / HDPE /
A configuration such as PE / LLDPE can also be adopted.

The packaging material of the present invention comprises a tearable film layer laminated on the surface of the gas barrier layer opposite to the heat sealable resin layer laminated side. As a method of laminating such a tearable film layer and a gas barrier layer, a method by dry lamination or a method of laminating via a hot-melt resin layer is used, but the gas barrier layer penetrates the contents a little and a gas barrier layer is formed. If there is a risk of penetration, it is desirable to use the latter method described above.
As such a tearable film layer, in the case of laminating with a gas barrier layer by a dry lamination method, for example, stretched polypropylene (for example, PG manufactured by Nisseki Plast Co., Ltd.), stretched nylon, stretched polyethylene (for example, Mitsui Toatsu). Each film such as manufactured by Kagaku Co., Ltd .: HIBRON P) is preferably used, and when laminated with a gas barrier layer and a hot-melt resin layer, for example, a co-extruded film of stretched polypropylene and LLDPE (for example, Mitsui Toatsu Chemical Co., Ltd.). Company-made: ASC-H), stretched polyethylene film and the like are preferably used.

The packaging material of the present invention can usually be produced by laminating the above-mentioned tearable film layer on the inside of a substrate. As a method of laminating such a base material and a tearable film layer, a method of heat lamination or dry lamination or a method of laminating via a hot melt resin layer is used, and when a hot melt resin is used, a coextrusion method is used. Is preferred. The base material used is P
A plastic film such as ET or stretched nylon, a laminate of a plastic film and paper, and the like are preferably used.

The packaging material of the present invention can be used as a standing pouch with a three-way or four-way seal or an inner bag of a bag-in-box by making it into a flexible package.

[0020]

By laminating a gas barrier layer between the heat-sealable resin layer and the tearable film layer as in the present invention, a high gas barrier property can be obtained and the tearability with the adjacent layer due to the penetration of the contents. Since the adhesion strength of the film layer is prevented from lowering, good tearability can be obtained regardless of the type of contents.

Further, by using the hot-melt resin layer for the lamination on the inner layer side of the gas barrier layer, peeling due to the use of the adhesive can be prevented.

Further, in the lamination of the gas barrier layer and the tearable film layer, and the tearable film layer and the outer layer such as the substrate, the use of the hot-melt resin allows the layers to be completely laminated without an adhesive or anchor coat. Therefore, the peeling can be completely prevented.

[0023]

EXAMPLES The present invention will be described more specifically with reference to the following examples.

Example 1 LLDPE / Ny / EVOH / N as a gas barrier layer
On one surface of a co-extruded film having a thickness of 25 μm (BH manufactured by Gunze Co., Ltd.) composed of y / LLDPE, LLDPE (manufactured by Aicello Chemical Co., Ltd .: Suzuron LL-145) having a thickness of 80 μm, In the meantime, melted polyethylene (M14P manufactured by Mitsui Petrochemical Industry Co., Ltd .: M14P) to a thickness of 15 μm.
m is extruded in the form of a film to laminate the two layers, that is, laminated by a so-called sand lamination method, and a longitudinally stretched polypropylene (hereinafter referred to as longitudinally stretched PP) / LLDPE is formed as a tearable film on the opposite surface of the gas barrier layer. A 25 μm-thick coextruded film (ASC-H, manufactured by Mitsui Toatsu Chemicals, Inc.) was laminated in the same manner by the above-mentioned sand lamination method, and on the outside thereof, a thickness of 1 was used as a substrate.
2 μm PET (manufactured by Toray Industries, Inc .: Lumirror P-60) with a two-component curing adhesive A-515 (manufactured by Takeda Co., Ltd.)
3.5 g / m ^{2 was} applied and laminated by a dry lamination method to prepare a packaging material having the following constitution.

PET / [vertically stretched PP / LLDPE] / PE / [LLDPE / Ny / (12 μm) (25 μm) (15 μm) (25 μm) EVOH / Ny / LLDPE] / PE / LLDPE (15 μm) (80 μm) // indicates that the layers were laminated by the dry lamination method (the same applies hereinafter).

Example 2 On one side of PET, SiO_XVacuum steamed to a thickness of 800Å
Of a gas barrier layer having a thickness of 12 μm formed by deposition
Inside, ie SiO_X80 μm in thickness of L
LDPE was melted with acid-modified polyethylene (Sho
WEDenko Co., Ltd .: ET184) with a film thickness of 20 μm
Extruded and laminated both by sand lamination method
On the opposite side of the gas barrier layer.
Longitudinally stretched PP / LLDPE coextrusion film
Layers are similarly laminated by the above-mentioned sand lamination method,
Furthermore, a stretched nylon with a thickness of 25 μm is used as a base material on the outside thereof.
(ONy) is laminated by the dry lamination method
A packaging material having the above structure was prepared. ONy // [longitudinal stretch PP / LLDPE] / acid-modified PE / PET-SiO (25 μm) (25 μm) (20 μm) (12 μm) / acid-modified PE / LLDPE (20 μm) (80 μm) At the same time, as a comparative example Packaging material with the following composition
Created respectively. Comparative Example 1 PET // [LLDPE / Ny / EVOH / Ny / LLDPE] / PE (12 μm) (25 μm) (20 μm) / LLDPE (80 μm) Comparative Example 2K-ONy: Polyvinylidene chloride coated stretched nylon Comparative Example 3Comparative Example 4Comparative Example 5Stretched PP: PG manufactured by Nisseki Plast Co., Ltd. The configurations of Examples 1 and 2 and Comparative Examples 1 to 5 are provided.
Create a standing pouch from the packaging material and mix
Stock solution A of the color developer for iron chloride (PH = 9.
0), undiluted solution B ( PH = 1.5), undiluted solution C (P H = 14.
0), and 500 ml each, and sealed, and at 50 ° C., 35
A 1-month storage test was performed under the conditions of% RH. Save
The results of the strike are shown in Table 1.

[0027]

[Table 1] * Tearability ○ Tear with a small force almost straight △ Tear, but force is required × No tearing From the results in Table 1, the packaging material of the present invention has an excellent gas barrier property and is stable with time. It can be seen that it has the property.

[0028]

As described above in detail, according to the present invention, it has a high gas barrier property against various chemicals, and further, the reduction of the adhesive strength of the tearable film layer due to the penetration of the contents. It is possible to obtain a packaging material that is stable and has a good tearability over time without causing it, and it is also possible to laminate without using an adhesive, and peeling due to the use of the adhesive can be prevented.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B65D 65/26 9145-3E 65/40 A 9145-3E

Claims (5)

[Claims] 1. A heat-sealing resin layer is laminated on one surface of a gas barrier layer via a hot-melt resin layer, and a base material is laminated on the other surface via a tearable film layer. And packaging materials. 2. The packaging material according to claim 1, wherein the gas barrier layer comprises a coextruded film having a saponified ethylene-vinyl acetate copolymer layer and nylon layers provided on both sides thereof. 3. The gas barrier layer comprises SiO _x (x is 1 to 2) on at least one surface of a plastic film.
The packaging material according to claim 1, wherein the packaging material comprises a vapor-deposited layer. 4. The packaging material according to claim 1, wherein the gas barrier layer and the tearable film layer are laminated by interposing a hot melt resin layer or by a dry lamination method. 5. A high-density polyethylene layer is provided on the gas barrier layer via a hot-melt resin layer, and a heat-sealing resin layer is further laminated on the high-density polyethylene layer via the hot-melt resin layer. The packaging material according to claim 1, wherein: