JPH0549336U - Gas barrier laminated stretch film - Google Patents

Abstract

(57) [Summary] [Purpose] Excellent gas barrier properties, and even if it is incinerated after use, it does not cause environmental pollution. Moreover, when it is used for stretch packaging, it adheres and is covered by self-adhesiveness. An attempt is made to provide a gas barrier laminated stretch film in which a torn portion does not peel off. [Structure] Self-adhesive resin surface layer (1) having a predetermined width,
Between the self-adhesive resin surface layer (1) between (1 ′),
A gas barrier resin core layer (3) other than polyvinylidene chloride having a width narrower than (1 ′) is formed from both ends (2) and (2 ′) of the self-adhesive resin surface layers (1) and (1 ′), respectively. A gas-barrier laminated stretch film sandwiched at intervals (L) and (L ′).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a stretch film used for stretch packaging. In particular, it is preferably used for stretch packaging of products such as foods that require gas barrier properties.

[0002]

[Prior Art]

 As the stretch film, use is made of polyvinylidene chloride, polyvinyl chloride, high-pressure polyethylene, linear low-density polyethylene, ethylene-vinyl acetate copolymer, or a single-layer film in which polybutadiene has self-adhesive properties. Has been. In particular, a stretch film made of polyvinylidene chloride resin has excellent gas barrier properties, and therefore has been suitably used for packaging products such as foods requiring gas barriers. However, when the film is incinerated after use, it emits toxic gas, and it has been shunned as it destroys the natural environment.

Regarding the laminated stretch film, a laminated stretch film composed of only a polyolefin resin is described in JP-A-60-79932, JP-A-3-76645, JP-A-3-86544, etc., and polyvinylidene chloride is used. A laminated stretch film having layers is described in JP-B-3-23097.

Therefore, as a stretch film having excellent gas barrier properties and causing no environmental pollution, a laminated stretch film having a gas barrier resin other than polyvinylidene chloride as a core layer is considered. However, gas barrier resins other than polyvinylidene chloride, for example, saponified ethylene-vinyl acetate copolymer, polyamide resin, polyethylene terephthalate resin, etc. are generally strong and are preferable resins for use as stretch film. is not. That is, the laminated stretch film using these resins is easily peeled off due to the elasticity of the film itself even if it is closely adhered and covered by the self-adhesiveness of the film surface.

[0005]

[Problems to be solved by the present invention]

 The present invention has an excellent gas barrier property, and does not cause environmental pollution even if it is incinerated after use. Moreover, when it is used for stretch packaging, it adheres due to self-adhesiveness and the covered part peels off. It is an object of the present invention to provide a gas barrier laminated stretch film that does not easily get damaged.

[0006]

[Means for Solving the Problems]

 The present invention has taken the following measures to solve the above problems. That is, between the self-adhesive resin surface layers on both sides, a gas barrier resin core layer other than polyvinylidene chloride having a narrower width than the surface layer is sandwiched from both ends of the surface layer. The distance from both ends of the self-adhesive resin surface layer to the end of the gas barrier resin core layer is preferably 20 to 100 mm, and the gas barrier resin core layer has an ethylene-vinyl acetate copolymer weight. A saponified product, a polyamide resin, or a single layer made of polyethylene terephthalate resin, or a laminated body made of these resins is used. Also, as the self-adhesive resin surface layer, use a laminate of the self-adhesive resin surface layer and the adhesive resin layer having adhesiveness to both the gas barrier resin core layer other than polyvinylidene chloride. Can be done.

The contents of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a gas barrier laminate stretch film of the present invention, and FIG. 2 is a sectional view taken along line a-a 'of FIG. A gas barrier resin core layer (3) other than polyvinylidene chloride is sandwiched between the self-adhesive resin surface layers (1) and (1 ') on both sides, and both ends (2 ), (2 ') to the end of the gas barrier resin core layer are laminated at intervals (L), (L'). Distances (L) and (L ') from the edge of the self-adhesive resin surface layer to the edge of the gas barrier resin core layer are preferably 20 to 100 mm.

As the gas barrier resin core layer (3) other than polyvinylidene chloride, saponified ethylene-vinyl acetate copolymer, polyamide resin, polyethylene terephthalate resin, or the like is used. If the distance (L) or (L ') from the edge of the self-adhesive resin surface layer to the edge of the gas barrier resin core layer is less than 20 mm, the self-adhesive resin may cause self-adhesion when used in stretch packaging. The edge of the film which is in close contact and is easily peeled off, and when it exceeds 100 mm, not only the wasteful portion is increased but also the packaging finish is not beautiful.

FIG. 3 shows that the self-adhesive resin surface layers (1) and (1 ′) on both sides have adhesiveness to both the self-adhesive resin surface layer and the gas barrier resin core layer other than polyvinylidene chloride. FIG. 2 is a cross-sectional view of a gas barrier laminate stretch film, which is a laminate with the adhesive resin layers (4) and (4 ′). FIG. 4 shows that the gas barrier resin core layer other than polyvinylidene chloride is a two-layer, three-layer type, that is, another gas barrier resin layer (6), (6) on both sides of the gas barrier resin layer (5). FIG. 3 is a cross-sectional view of a gas barrier laminated stretch film when ') is laminated.

The adhesive resin layers (4) and (4 ′) having adhesiveness to both the self-adhesive resin surface layer and the gas barrier resin core layer other than polyvinylidene chloride are produced by a dry lamination method. In the case of using a conventional adhesive, a generally used adhesive may be used. In the case of producing by a coextrusion method, an unsaturated fatty acid-modified polyolefin resin generally used in the past may be used. When the gas barrier resin core layer is a laminate, a laminate in which at least one layer is made of the saponified ethylene-vinyl acetate copolymer, polyamide resin, polyethylene terephthalate resin, or the like is used. For example, in the case of a two-kind three-layer body consisting of only a gas barrier resin as shown in FIG. 4, a saponified ethylene-vinyl acetate copolymer layer is provided in the center layer and polyamide resin layers are provided on both sides of the layer. A laminated body or the like is used.

The gas barrier laminated stretch film of the present invention includes a method of forming a gas barrier resin between two self-adhesive resin surface layer films in a film shape narrower than the surface layer film. A method of extruding and laminating, etc. can be suitably used. It can also be manufactured by a dry lamination method or a thermocompression bonding method which has been generally used conventionally. The laminate of the self-adhesive resin surface layer and the gas barrier core layer is preferably obtained by the coextrusion method.

As a method of stretch-packing using the gas barrier laminate stretch film of the present invention, a method generally used in the past can be used as it is. However, during stretch packaging, the edges of the film that do not have the gas barrier resin core layer are overlapped with the portions that have the gas barrier resin core layer so that they adhere closely to each other. Encapsulation of the material is necessary to enhance the gas barrier properties of the resulting package.

The gas barrier laminate stretch film of the present invention can be stretch-wrapped and then passed through a heat-shrinking tunnel to be heat-shrinked to be stretch-shrink-wrapped so as to increase the tightness of the package. It can be used.

[0014]

[Action]

 Since the gas barrier laminated stretch film of the present invention does not have a gas barrier resin core layer other than polyvinylidene chloride on both edges, the waist of the portion is weak, and the waist of the film required as a stretch film is weak. Have In addition, this part is a part necessary for the films to be adhered and covered in stretch packaging. Therefore, the stretch film of the present invention can be satisfactorily stretch-wrapped even if a gas-barrier resin having a strong rigidity such as ethylene-vinyl acetate copolymer is used.

Since the self-adhesive resin surface layers are provided on both surfaces of the gas barrier resin core layer, even if pinholes are formed in the gas barrier resin core layer, the gas barrier property is significantly reduced. Will never occur. Furthermore, by laminating resins having different gas barrier properties to form a gas barrier resin core layer, it is possible to have an optimum gas barrier property for various gases required by the packaged object.

[0016]

【effect】

 The laminated stretch film having gas barrier properties of the present invention is not only a film having excellent gas barrier properties, but also a film having excellent adhesion required for stretch packaging. Moreover, even if it is incinerated after use, no toxic gas that would cause environmental damage is generated.

[Brief description of drawings]

FIG. 1 is a perspective view of a gas barrier laminated stretch film of the present invention.

FIG. 2 is a sectional view taken along the line aa ′ of FIG.

FIG. 3 is a cross-sectional view of a gas barrier laminate stretch film in which the self-adhesive resin surface layers on both sides are a laminate with an adhesive resin layer.

FIG. 4 is a sectional view of a gas barrier laminate stretch film in which the gas barrier resin core layer is a laminate.

[Explanation of symbols]

1.1 '. Self-adhesive resin surface layer 2.2 '. Edge of self-adhesive resin surface layer 3. Gas barrier resin core layer other than polyvinylidene chloride 4.4 '. 4. Adhesive resin layer having adhesiveness to both the self-adhesive resin surface layer and the gas barrier resin core layer other than polyvinylidene chloride 5. Gas barrier resin layer 6.6 '. Other gas barrier resin layer L. L '. Distance from edge of self-adhesive resin surface layer to edge of gas barrier resin core layer

─────────────────────────────────────────────────── ───Continued from the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B32B 27/36 7016-4F

Claims (4)

[Scope of utility model registration request] 1. A self-adhesive resin surface layer (1) having a predetermined width,
Between the self-adhesive resin surface layer (1) between (1 ′),
A gas barrier resin core layer (3) other than polyvinylidene chloride having a width narrower than (1 ′) is formed from both ends (2) and (2 ′) of the self-adhesive resin surface layers (1) and (1 ′), respectively. A gas-barrier laminated stretch film sandwiched at intervals (L) and (L ′). 2. Self-adhesive resin surface layers (1), (1 ′)
The gas barrier laminate stretch film according to claim 1, wherein the distances (L) and (L ') from both ends of the gas barrier resin core layer (3) other than polyvinylidene chloride are 20 to 100 mm, respectively. 3. A gas barrier resin core layer (3) other than polyvinylidene chloride, which is a saponified ethylene-vinyl acetate copolymer, a polyamide resin, or a single layer composed of a polyethylene terephthalate resin, or from these resins. The gas barrier laminate stretch film according to claim 1, wherein the stretch film is a laminated body. 4. Self-adhesive resin surface layer (1), (1 ′)
Is a laminate of adhesive resin layers (4) and (4 ') having adhesiveness to both the self-adhesive resin surface layer and the gas barrier resin core layer other than polyvinylidene chloride. Gas barrier laminated stretch film.