JPH09141795A - Wrapping material for refrigeration - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a bag breaking accident from occurring due to freezing after water absorption by a nylon film, in a wrapping material for refrigeration using the nylon film in a surface material. SOLUTION: This wrapping material for refrigeration consists of at least, two layers or more of plastic film such as a thermally fusible layer and a surface layer, and the surface layer is nylon film. Under this composition, this nylon film has a water-resistant layer for preventing water from being absorbed, and is urethane resin coating nylon film, acrylic resin coating nylon film or vinylidene chloride resin coating nylon film. The surface of the wrapping material is a coated surface, or the nylon film is a metal vapor-deposited nylon film or a metal oxide vapor-deposited nylon film. In addition, the surface of the wrapping material is vapor-deposited.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging material for packaging frozen foods, livestock cooling materials and other contents that require freezing.

[0002]

2. Description of the Related Art Conventionally, in a typical packaging material for packaging contents requiring freezing, most of them are bags made of a laminated packaging material using a nylon film as a surface material.

[0003]

However, in the material for laminating the nylon film as described above, nylon is present on the surface of the packaging material, and the nylon on the surface absorbs water, so that the material is once exposed to room temperature or the lid is covered. When warm air flows into the showcase due to opening and closing, etc., nylon absorbs the dew condensation water that forms on the surface, and when the dew condensation water adheres, the bags overlap and freeze, or when dew condensation water adheres. If the metal contacts the showcase, the condensed water freezes under the condition that it binds with nylon and acts like an adhesive, trying to peel the frozen bags from each other, or removing the frozen bag from the showcase. When trying to do so, the nylon film often breaks and punctures the bag.

As a countermeasure for this, there is a packaging material using a polyethylene terephthalate (hereinafter referred to as PET) film or a biaxially oriented polypropylene (hereinafter referred to as OPP) film as a packaging material for freezing, but the strength of the nylon film is not reached. However, there is a problem that pinholes are easily generated. There are also three-layer packaging materials that use PET or OPP as the surface material and a nylon film as the intermediate layer with the heat-sealing layer, but the packaging material becomes stiff and the touch feels poor, and the cost is high. There will be problems such as.

[0005]

SUMMARY OF THE INVENTION In view of the above problems, the present invention is a package in which two or more layers of plastic films, at least a heat-sealing layer and a surface layer, are laminated and the surface layer is a nylon film. In the material, the nylon film is a nylon film having a water resistant layer for preventing water absorption provided on its surface, which is a packaging material for freezing. The nylon film is a urethane resin-coated nylon nylon film, an acrylic resin-coated nylon film, a vinylidene chloride resin-coated nylon film, and the packaging material surface is a coated surface, or the nylon film is a metal-deposited nylon film. A film, a metal oxide vapor deposition nylon film, characterized in that the packaging material surface is a vapor deposition processed surface.

It is an object of the present invention to prevent a bag breakage accident caused by freezing of a nylon film after absorbing water in a freezing packaging material using a nylon film as a surface material. This can be achieved by providing a water-resistant layer that prevents water absorption of nylon on the surface of the packaging material, or by using a film having a coating that prevents water absorption of nylon.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below with reference to the drawings. FIG. 1 shows the layer structure of the packaging material for freezing of the present invention. The heat-sealing layer 1, the adhesive layer 2, the nylon film layer 3, and the water resistant layer 4 are formed from the back surface of the packaging material.

For the heat-sealing layer 1, a resin having a heat-sealing property, a high sealing strength, a cold resistance and an impact resistance is used. Linear low density polyethylene (hereinafter LL
DPE) is mainly used. Besides, ethylene vinyl acetate copolymer (hereinafter referred to as EVA), unstretched polypropylene, ionomer and the like can be used. The effect of the present invention does not depend on the material of the heat-sealing layer.

The adhesive layer 2 has an adhesive such as a urethane-based two-component curing type adhesive or a melted polyethylene resin by a polysand method as an adhesive layer. The effect of the present invention is not affected by the type of adhesive or the method of laminating such as extrusion coating.

The nylon film layer 3 may be a stretched nylon film or a non-stretched nylon film. Nylon film is widely used as a packaging material for refrigeration because of its impact resistance and puncture resistance. A water resistant layer 4 is provided on the surface of this nylon film. The back surface becomes the corona-treated surface 5.

The water resistant layer 4 is a coating layer of urethane resin, acrylic resin, vinylidene chloride resin or the like, a metal vapor deposition layer of aluminum or the like, or a metal oxide vapor deposition layer of silica or the like. In any case, the objective is achieved if nylon is not exposed on the surface of the packaging material and the surface is covered with a water-insoluble substance.

Generally, urethane resin, acrylic resin, vinylidene chloride resin or the like is applied to an uncoated nylon film, but as a commercially available nylon film already provided with a water resistant layer, Toyobo is available. There are "P7030" manufactured by Co., Ltd. ("is the product name, the same applies below)," Emblem ONM "and" Emblem NX "manufactured by Unitika Co., Ltd. If you want to make the surface a waterproof layer, the surface opposite to the waterproof layer has been treated with corona discharge to improve the wetting of the adhesive.
It is desirable to use "Emblem ONMB" manufactured by Komon and "Bonile QC" manufactured by Kojin Co., Ltd. However, when the strong adhesive strength between the films is not required due to the light content, the nylon surface may not be subjected to corona discharge treatment.

[0013]

【Example】

[Example 1] A urethane resin is applied to the front surface of a nylon film 15µ, and a corona treatment is applied to the back surface. Next, a 40 μm thick L-LDPE film and a urethane-based two-component curing type adhesive are bonded so that the adhesive surface is a corona-treated surface and the urethane resin application surface is the surface of the packaging material, and the packaging is performed. Create a bag of 15 cm x 22 cm with materials,
After adding 200 ml of water and freezing it once, it was taken out from the freezer, the water vapor in the air was condensed on the surface of the packaging material, two bags were piled up and stored in a freezer at 40 ° C below freezing for 2 days, and then 2 bags 1 A drop test of 1 m each was performed. Here, the L-LDPE film is used as the heat-sealing layer, but other materials such as EVA, unstretched polypropylene, and ionomer can be used, and the effect of the present invention depends on the material of the heat-sealing layer. In addition, the effect is not affected by the type of adhesive or the method of laminating such as extrusion coating.

[Example 2] An acrylic resin was applied to the surface of a nylon film 15µ, and an L-LDPE film having a thickness of 40µ was laminated in the same manner as in Example 1, and the packaging material was used in the same manner as in Example 1. , A test piece was prepared, and a drop test was performed.

Example 3 A vinylidene chloride-coated nylon film having a thickness of 15 μ and an L-LD having a thickness of 40 μ
A PE film was attached in the same manner as in Example 1, and a test body was prepared using the packaging material in the same manner as in Example 1, and a drop test was performed.

Example 4 An aluminum vapor-deposited nylon film having a thickness of 15 μm and an L-LDPE film having a thickness of 40 μm were laminated in the same manner as in Example 1, and the packaging material was used to prepare a test body in the same manner as in Example 1. Then, a drop test was performed.

[Example 5] A silica-deposited nylon film having a thickness of 15 µm and an L-LDPE film having a thickness of 40 µm were laminated in the same manner as in Example 1, and a test body was prepared by using the packaging material as in Example 1. Then, a drop test was performed.

COMPARATIVE EXAMPLE 1 A nylon film having a corona-treated nylon film and a corona-treated L-LDPE film having a water resistant layer on the front surface and a corona-treated surface on the back surface was prepared as in Example 1 so that the corona-treated surface could be an adhesive surface. Similarly, they are stuck together, that is, the nylon is exposed on the surface of the packaging material. A test body was prepared from the packaging material in the same manner as in Example 1, and a drop test was performed.

The results of the drop test are shown in Table 1. The rupture bag described here is only for rupturing the bag by freezing of the same bag, and the test piece whose heat-sealed portion is cut by the impact at the time of dropping is I have removed it. No bag breakage occurred in the set (bag) whose surface was an easily water-resistant adhesive surface. If the bag is broken due to freezing,
The feature is that there are no scratches or scratches around the hole, and it can be distinguished from the pinhole or bag that is usually dropped or pierced from the appearance.

[0020]

[Table 1]

[0021]

As is apparent from the above description, the present invention is
In a freezing packaging material that uses nylon film as the surface material, by providing a water resistant layer that prevents nylon water absorption on the surface of the nylon film, it is possible to prevent bag breakage accidents caused by freezing after the nylon film absorbs water. It is possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing a layer structure of an embodiment of a packaging material for freezing according to the present invention.

FIG. 2 is a diagram showing a layer structure of a comparative example with respect to an example of the packaging material for freezing according to the present invention.

[Explanation of symbols]

 1 Heat-fusion layer 2 Adhesive layer 3 Nylon film layer 4 Water resistant layer 5 Corona treated surface

Claims (3)

[Claims] 1. A packaging material in which two or more plastic films, at least a heat-sealing layer and a surface layer, are stuck together, and the surface layer is a nylon film, wherein the nylon film has a water resistant layer which prevents water absorption on the surface. A packaging material for freezing, which is a nylon film provided. 2. The nylon film is a urethane resin-coated nylon nylon film, an acrylic resin-coated nylon film, or a vinylidene chloride resin-coated nylon film, and the packaging material surface is a coated surface. The packaging material for freezing according to claim 1. 3. The refrigerating machine according to claim 1, wherein the nylon film is a metal vapor-deposited nylon film film or a metal oxide vapor-deposited nylon film, and the packaging material surface is a vapor deposition processed surface. Packaging material.