JPH0999973A - Film for packaging bag and packaging bag formed thereby - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide sufficient sealability and reasonable easy-peelability by prescribing the seal strength between film layers which are polymerized and adhered to a base layer of a prescribed thickness made of a synthetic resin. SOLUTION: A base layer A of 15-30μ in thickness made of a synthetic resin, an adhesive layer B, and a printing layer C having easy sealability with the adhesive layer B are uniformly provided in an inter-layer structure. When the base layer A is polymerized and adhered, the seal strength between the film layers is limited to 1.0kgf to 2.0kgf. The base layer is preferably formed of one or more kinds of materials selected from the group consisting of polyethylene, polypropylene, and polyethylene copolymer. When the adhered film is peeled, the breakage of the base layer A reaches the space between the printing layer C and the adhesive layer B, and then, the film is continuously broken from both parts of the printing layer C and the adhesive layer B. Reasonable easy peelability can be obtained in this breaking process, and at the same time, the sufficient seal strength can be secured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging bag having a high easy peeling property, that is, an adhesive portion can be easily peeled off and can be opened with a small force, and a film therefor.

[0002]

2. Description of the Related Art In a packaging bag for snacks or the like produced by a bag-filling method, it is necessary to achieve sufficient sealing at the heat-sealed portion of a synthetic resin film to store the confectionery. The conventional packaging bag has sufficient sealing property, but generally the sealing strength of the adhesive portion is as large as 2.0 kgf to 5.0 kgf, and there is a problem that it is difficult to peel and open the adhesive portion. . On the other hand, in Japanese Utility Model Publication No. 4-7073, etc., a release ink layer and an adhesive ink layer are partially overlapped on a base film, and a colored ink layer is further formed to cover them, in order to prevent unauthorized resealing. Article packaging bags have been proposed. According to this, at the time of opening, the film of the release ink layer is selectively released from the base film, so that the film is peeled and separated, and the pattern drawn by the release ink layer appears, so that the presence or absence of the opening can be determined. Becomes By the way, in a packaging container for snacks or the like, it is necessary to secure a certain sealing strength between the synthetic resin film layers for the purpose of storing the contents, and yet to secure an easy peeling property in the sealing portion. However, the configuration in which the release ink layer is partially provided, which is disclosed in Japanese Utility Model Publication No. 4-7073, etc., has a substrate layer (heat-fusible resin layer) A, an adhesive layer, as shown in FIG. (Coloring ink layer) B, a release ink layer (leveling ink layer) D partially provided corresponding to a predetermined pattern, and an outer layer (base film) E. When this film is adhesively sealed with a strength that can achieve a sufficient hermeticity, since the release ink layer D is partially provided when the film is peeled off, the outer layer E and the adhesive by the ink layer D are provided. There is a problem that peeling between the layer B and the substrate layer A is easily interrupted, and good easy peeling property cannot be secured over the entire adhesive seal portion.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of conventional synthetic resin film packaging bags.
An object of the present invention is to provide a packaging bag having a sufficient sealing property and a rational easy peeling property, and a film for producing the same.

[0004]

The first invention of the present application is an interlayer structure having a base material layer made of a synthetic resin and having a thickness of 15 μm to 30 μm, an adhesive layer, and a printing layer having an easy peel property with the adhesive layer. When the above base material layers are polymer-bonded (heat-sealed), the sealing strength between the film layers is 1.0 kgf to 2.0.
It is a film for packaging bags, which is characterized by being kgf.
A second invention is characterized in that the base material layer is formed of a combination of one or more selected from the group consisting of polyethylene, polypropylene, and a polyethylene-based copolymer. A third invention is characterized in that the printing layer is formed from a combination of one or more selected from the group consisting of a release varnish, a surface printing ink, and a silicone-based release agent.
A fourth invention is characterized in that the adhesive layer is formed of one or more combinations selected from the group consisting of an adhesive for dry lamination, a solventless adhesive, polyethylene, and a polyethylene-based copolymer. And

According to a fifth aspect of the present invention, the laminate strength between the adhesive layer and the printing layer is 10 gf to 40 gf when polymerized and adhered via the base material layer. In the sixth invention, the breaking strength of the base material layer is 1.0 kgf to 1.5 kgf. A seventh invention provides a film having a base layer made of a synthetic resin and having a thickness of 15 μm to 30 μm, an adhesive layer, and an interlayer structure uniformly having a printing layer having an easy peel property with the adhesive layer,
The packaging bag is characterized by being polymerized and bonded (heat-sealed) via the above-mentioned base material layer so that the sealing strength between the films is 1.0 kgf to 2.0 kgf.

[0006]

According to the first aspect of the present invention, when the adhered film is peeled off, the base material layer is broken, and the breakage occurs between the printing layer and the adhesive layer, and then the printing layer and the adhesive layer are bonded together. The film continuously breaks from both layers of the agent layer. A reasonable easy peeling property can be obtained by such a breakage process, and at the same time, a sufficient sealing strength for storing the contents can be secured. The thickness of the base material layer is 15
When it is at least μ, the necessary preservability and strength of the contents and the sealing strength of the film can be obtained. On the other hand, when it is at most 30 μ, the base material is used when peeling the film or opening the container formed by the film. The layer can be smoothly broken in the longitudinal direction to transmit the tear to the adhesive layer and the printing layer, and a proper easy peel can be achieved. In addition, the sealing strength between the films
By setting the content to 1.0 kgf or more, a sufficient sealing strength for preserving the contents can be obtained, and on the other hand, setting the content to 2.0 kgf or less can easily achieve the easy peel function. In addition, since the above-mentioned interlayer structure is uniformly formed, there is an effect that breakage is not interrupted and a separate interlayer structure is not formed, which is economical.

The partial structure (adhesive portion or the like) of the interlayer structure has an effect that the easy peeling property can be obtained only in the specific region. In the second invention, the base material layer made of polyethylene, polypropylene, and a polyethylene-based copolymer has an advantage that it can be easily polymer-bonded (heat-bonded) to other materials and is inexpensive. . In the third invention, the printed layer of the release varnish, the surface printing ink, and the silicone-based release agent has an advantage that the easy peel property between the adhesive layer and the other printed materials is good. In the fourth invention, the dry laminating adhesive, the solvent-free adhesive, the polyethylene, and the polyethylene-based copolymer adhesive layer have a proper laminating strength with respect to those of other adhesives, It has the advantage that the easy peeling property between is good. Third
In the invention, the printing layer having a thickness of 1 μm to 3 μm has an advantage that desired easy peeling property and good printing can be achieved.
In the fourth invention, the adhesive layer having a thickness of 2 μ to 20 μ has an advantage that a thicker one has a uniform thickness and a thinner one has an advantage that a strong laminating strength can be obtained. .

In the fifth invention, the laminating strength between the base material layer and the adhesive layer is preferably about 100 gf to 200 gf. Further, the laminating strength between the adhesive layer and the printing layer is 10
Those having gf to 40 gf have the advantage of having a good easy peel property with respect to those larger than this, and have the advantage of obtaining suitable laminate strength without peeling with those smaller than this. In the sixth invention, the breaking strength of the base material layer is
The one having a weight of 1.0 kgf to 1.5 kgf has an advantage that the easy peel of the film is better than the one having a larger size, and the sealing strength capable of sufficiently protecting the contents is less than the smaller one. Has the advantages obtained. Seventh
In the invention, when the adhered film is peeled off, the base material layer breaks, the breakage reaches between the printing layer and the adhesive layer, and then from both portions of the printing layer and the adhesive layer. The film breaks continuously. A reasonable easy peel property can be obtained by such a breakage process. In this case, the packaging bag having a height of about 100 mm to 400 mm and a width of about 100 mm to 300 mm can be easily opened by grasping the side portions with both hands to utilize the easy peel structure of the adhesive portion of the present invention. It has the advantage that the packaging bag can be opened.

Further, a packaging bag having a width of the area for polymerization adhesion (heat fusion) of 5 mm to 20 mm has an advantage of having a good easy peeling property with respect to a larger size, but smaller than this. It has the advantage that the hermeticity of the contents is superior to that of objects.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011]

[First Aspect] As shown in FIG. 1, the packaging bag of the first aspect of the present invention can be prepared by a known extrusion laminating method, dry laminating method, solventless laminating method or the like according to the material of the adhesive. From the inside that comes into contact with the inside, a substrate layer A made of an aluminum vapor-deposited polypropylene layer having a thickness of about 30μ, polyethylene, polypropylene, a polyethylene-based copolymer,
An adhesive layer B such as a dry laminating adhesive or a solventless adhesive having a thickness of about 2 μ, and a peeling varnish, a surface printing ink, a silicone-based peeling agent, etc. having a thickness of about 2 μ provided on a seal portion outside thereof. A laminated film having a structure in which an easy peel printing layer C, a gravure printing ink layer D having a thickness of about 2 μm, and an outer layer E such as a stretched polypropylene, polyester, nylon having a thickness of about 25 μm are sequentially laminated is manufactured. In the laminate film, the laminate strength between the substrate layer A and the adhesive layer B is about 150 gf, and the laminate strength between the adhesive layer B and the easy peel printing layer C is about 30 gf.
The lamination strength between the adhesive layer B and the gravure printing ink layer D is about 30 gf, the gravure printing ink layer D and the outer layer E.
The laminate strength between and is about 100 gf.

[0012]

[Second Embodiment] As shown in FIG. 1, two laminated films shown in the first embodiment were welded to each other with a width of about 15 mm at an end portion to form a welded portion 10. In this case, the sealing strength between the films of the welded portion 10 of the laminated film is about 1.
It was 2 kgf. When the two laminated films are separated from each other, the substrate layer A starts to be ruptured by a light force, and then the rupture reaches the easy peel printing layer C, and the easy peel printing layer C is ruptured to easily seal the seal. I was able to open it.

[0013]

[Third Aspect] The laminated film shown in the first aspect is cut into a width of 425 mm and a height of 260 mm, folded in two at the center in the width direction, and the upper and lower ends and side ends are heat-welded to a width of about 15 mm. Then, a packaging bag having a width of about 200 mm and a height of about 260 mm was formed. Filled with about 2000 cm ² of potato chips 2
0 was 80 g, and the hollow ratio was about 90%. The opening could be easily performed by applying a force for separating the height middle part of the packaging bag. The sealing strength and the laminating strength in the present invention described above means that the ends of two strip-shaped films having a width of 15 mm are heat-sealed (laminated) with a length of 15 mm, and the other end of each is left with a length of 40 to 80 mm. Pull both ends at a speed of 300 ± 20 mm per minute,
It is obtained by a method of measuring the maximum load until the heat seal (laminate) peels off. This method
This is in accordance with the strength and other testing methods of the "Standards for equipment and containers and packaging" in the Food Sanitation Law.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an interlayer structure of a packaging bag film according to a first aspect of the present invention.

FIG. 2 is a sectional view of a packaging bag according to a second aspect of the present invention.

FIG. 3 is a cross-sectional view showing an interlayer structure of a conventional packaging bag film.

[Explanation of symbols]

 A substrate layer, B adhesive layer C easy peeling printing layer D gravure printing ink layer E outer layer 10 adhesive part 20 potato chips

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B65D 65/40 B65D 65/40 C

Claims (7)

[Claims] 1. The thickness of synthetic resin is 15 μm to 30 μm.
Of a base layer, an adhesive layer, and an interlayer structure having a printing layer having an easy peel property with the adhesive layer uniformly, and when the base layer is polymerized and adhered (heat-bonded), A film for a packaging bag, which has a sealing strength of 1.0 kgf to 2.0 kgf. 2. The packaging bag according to claim 1, wherein the base material layer is formed of one or more combinations selected from the group consisting of polyethylene, polypropylene, and a polyethylene-based copolymer. Film. 3. The package according to claim 1, wherein the printing layer is formed from one or more combinations selected from the group consisting of a release varnish, a surface printing ink, and a silicone-based release agent. Film for bags. 4. The adhesive layer is formed from a combination of one or more selected from the group consisting of an adhesive for dry lamination, a solventless adhesive, polyethylene, and a polyethylene-based copolymer. The film for a packaging bag according to claim 3. 5. A laminate strength between the adhesive layer and the printing layer is 1 when polymerized and adhered via the base material layer.
The packaging bag film according to claim 1 or 4, which has a weight of 0 gf to 40 gf. 6. The breaking strength of the base material layer is from 1.0 kgf to 1.
The film for a packaging bag according to claim 1 or 4, which has a weight of 5 kgf. 7. The thickness of synthetic resin is 15 to 30 μm.
The film having a base layer, an adhesive layer, and an interlayer structure having a printing layer having an easy peeling property with the adhesive layer, and having a seal strength between the films of 1.0 kgf to 2.0 kg.
Polymerization adhesion (heat fusion) through the above base material layer so as to be f
A packaging bag characterized by being formed.