JPH10100350A - Easy peel co-extrusion composite film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite film for a bottom material having high impact strength, good in moldability, transparency and rigidity and excellent in the easy peelability with a lid material film. SOLUTION: An easy peel co-extrusion composite film is constituted so that a heat-sealble resin layer 1 is arranged to one outermost layer and an amorphous polyester resin layer 5 with a thickness of 200-500μm is arranged to other outermost layer and a barrier resin layer 3 composed of an ethylene/vinyl acetate copolymer saponified matter layer or consisting of a polyamide resin layer and an ethylene/vinyl acetate copolymer saponified matter layer is arranged as an intermediate layer and an oxidizing layer 11 is formed on the surface of the heat-sealable resin layer 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a co-extruded composite film, and in particular, has high impact strength, good formability, transparency,
The present invention relates to a co-extruded composite film for a bottom material having rigidity (lumpy) and having a suitable easy peel property when sealed with a lid material film for a gas pack.

[0002]

2. Description of the Related Art In a gas pack product in which a bottom material is formed by deep drawing and the content is filled, and the lid material is heat-sealed, a method for imparting easy-opening properties to the heat-sealing side of the lid material and the bottom material is provided. There is a method of providing a cohesive failure type easy peel layer to be peeled in a layer and a method of providing an interlayer peeling type easy peel layer to be peeled between layers.

The above-described method of providing an easy-peel layer on a cover material or a bottom material is generally used because the easy-peel strength is stable. However, it is necessary to increase the number of layers and the cost is increased accordingly. In addition, there is a problem, and it is difficult to select a suitable raw material, and the temperature dependency of the easy peel strength is large, which makes it difficult to select an appropriate raw material. There was a problem that it was difficult to use because it was stable.

[0004]

SUMMARY OF THE INVENTION The present invention provides a coextruded composite film having a stable easy-peel property by forming an oxide layer on the surface of a polyolefin resin layer used as a normal heat seal layer. The purpose is to:

[0005]

The above object is achieved by the following means.

That is, according to the present invention, one outermost layer has a heat-sealable resin layer and the other outermost layer has a thickness of 200 to 500 μm.
An amorphous polyester resin layer is disposed, and a barrier resin layer composed of an ethylene vinyl acetate copolymer saponified layer or a polyamide resin layer and an ethylene vinyl acetate copolymer saponified layer is disposed as an intermediate layer, and the heat sealing is performed. The present invention proposes an easy-peel co-extruded composite film having an oxide layer formed on the surface of a conductive resin layer.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial cross-sectional view showing the configuration of an easy peel coextruded composite film of the present invention.

As shown in FIG. 1, the coextruded composite film of the present invention has a heat-sealable resin layer 1 on one outermost layer and an amorphous polyester resin layer 5 (hereinafter A-PE) on the other outermost layer.
It is called T. ), And a saponified ethylene vinyl acetate copolymer layer (hereinafter referred to as EVOH)
That. ), An adhesive layer and a polyamide resin (hereinafter, referred to as NY) layer, a laminate of EVOH and NY, a laminate of NY, EVOH and NY, or a barrier resin layer 3 composed of only EVOH. And an oxide layer 11 on the surface of the heat-sealable resin layer 1.
Is formed. The thickness of the intermediate layer is 15-30
The range of μm is preferred.

As the outermost heat-sealable resin layer 1, low-density polyethylene (hereinafter, referred to as LDPE), linear low-density polyethylene (hereinafter, LLDPE) is used.
That. ), Polyethylene-based resins such as ethylene-vinyl acetate (hereinafter referred to as EVA) and the like are preferably used.
The thickness is preferably in the range of 20 to 30 μm. The other outermost layer, A-PET5, preferably has a thickness of 200 to 500 μm. The adhesive layers 2 and 4 include acid-modified polyolefin resins and the like, and the thickness is preferably in the range of 10 to 20 μm. If the thickness of A-PET5 is less than 200 μm, there is a problem that it is not stiff and cracks are easily generated.
If the thickness exceeds 0 μm, there is a problem that the cutting property of the film is inferior.

Further, it is necessary to form an oxidized layer 11 on the surface of the heat seal resin layer 1. The method for forming the oxidized layer is as follows. The extrusion temperature of the polyolefin resin which is the heat seal resin layer 1 is 290 to 340. If the extrusion temperature is lower than 290 ° C., the composite film of the present invention cannot be provided with heat sealability, and the extrusion temperature is 3 ° C.
If the temperature exceeds 40 ° C., there is a problem that the resin is decomposed, and the above temperature range is preferable. Usually LDPE, LL
Extrusion temperature of polyethylene such as DPE is 240-260 ° C
However, by extruding with a resin having a high melting temperature such as A-PET, the extrusion temperature of polyethylene can be easily increased to 290 ° C. or higher, and the surface of the polyolefin resin layer is uniformly oxidized, and stable. Easy peelability can be imparted.

[0012]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. Example 1 A composite film comprising the following five layers was co-extruded so that the extrusion temperature of the heat-sealing resin layer was 290 to 310 ° C to obtain a composite film of the present invention.

LDPE (thickness: 30 μm) / EVOH (thickness: 10 μm) / 6-66NY (thickness: 10 μm) / adhesive layer (thickness: 12 μm) / A-PET (thickness: 300 μm) The method was evaluated. Table 1 shows the results.

Evaluation method: Easy peelability Using the above composite film, diameter 100 mm, depth 20 mm
Bottom material is obtained by drawing, and filled with sliced ham, filled with an inert gas, and covered with a lid material (biaxially stretched 6 Ny (50 μm)).
And a polyethylene film (30 μm dry laminate) were heat-sealed at 130 ° C. for 2 seconds, and then the lid was peeled off with a finger to evaluate the peeled state. Those that could be easily peeled were marked with (○), and those that were difficult to open were marked with (x).

Easy peel strength The sealing portion between the bottom material and the lid material is cut out, and a pulling speed of 20
A T-type peel test was performed at 0 mm / min. Example 2 Example 1 The LDPE of the heat-sealing resin layer was changed to LLDPE.
(Thickness: 30 μm), and a composite film consisting of five layers was co-extruded such that the extrusion temperature of the heat-sealing resin layer was 290 to 310 ° C. to obtain a composite film according to the invention.

The obtained composite film was evaluated in the same manner as in Example 1. Table 1 shows the results. Comparative Examples 1 and 2 A composite film having the same configuration as in Examples 1 and 2 was co-extruded so that the extrusion temperature of the heat-sealing resin layer was 285 ° C.

The obtained composite film was evaluated in the same manner as in Example 1. Table 1 shows the results. Comparative Examples 3 and 4 A composite film having the same configuration as in Examples 1 and 2 was co-extruded so that the extrusion temperature of the heat-sealing resin layer was 240 to 260 ° C.

The obtained composite film was evaluated in the same manner as in Example 1. Table 1 shows the results.

[0019]

[Table 1]

[0020]

According to the present invention, it is possible to stably provide low-cost and easy-peeling at an interface peeling type in which peeling is performed at a seal interlayer interface between the lid member and the bottom member.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a composite film of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat sealable resin layer 11 Oxidized layer 2, 4 Adhesive layer 3 Barrier resin layer 5 Amorphous polyester resin layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B32B 27/34 B32B 27/34 B65D 71/08 B65D 71/08

Claims (1)

[Claims] 1. A heat-sealing resin layer on one outermost layer and an amorphous polyester resin layer of 200 to 500 μm on the other outermost layer, and a saponified ethylene vinyl acetate copolymer layer or a polyamide resin layer as an intermediate layer. An easy-peel coextruded composite film, comprising a barrier resin layer composed of a saponified layer of ethylene vinyl acetate copolymer and an oxide layer formed on the surface of the heat-sealing resin layer.