JPH08217054A - Gas barrier type paper container - Google Patents

Abstract

PURPOSE: To improve the gas barrier property without letting a liquid penetrate in paper, and minimize the effect to the environment by affixing a tape made of a film with a gas barrier layer on the internal side of a joined part of ends of a container consisting of a laminate which includes a gas barrier layer. CONSTITUTION: For a cylindrical container, a low density polyethylene 11, silicon dioxide 12, low density polyethylene 13, paper 14 and low density polyethylene 15 are laminated in order from the side which comes into contact with a content. Then, on the internal side of a part wherein the ends of the cylindrical container are affixed to each other, a tape 18 consisting of a film for which a layer of silicon dioxide 17 is provided on both surfaces of polyethylene 16 is heat-bonded in such a manner that the tape 18 may cover the end surface of the laminate under a U-shape. By this method, a gas such as oxygen, etc., is prevented from entering the inside of the container from the end surface of the joined part of the body. At the same time, since the gas barrier layer is an inorganic oxide such as silicon dioxide, etc., the container can be totally incinerated after usage, and also, does not exert an unfavorable effect to the environment as trash.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a part having a tubular body having a tubular body formed by laminating ends of a sheet material made of a laminated body including paper, plastic and a gas barrier layer, and pasting the ends together. The present invention relates to a container on which a tape made of a film having a gas barrier property is attached, and particularly to a container having excellent gas barrier property and incineration property.

[0002]

2. Description of the Related Art Conventionally, when a paper container made of a laminated body containing paper is filled with a liquid such as juice or liquor, a plastic film (1) (polyethylene or the like) is provided on the surface in contact with the liquid to prevent the liquid from penetrating into the paper. ) Were stacked. Further, the aluminum foil (2) was laminated to prevent the permeation of gas such as oxygen. However, in this configuration, since the end surface of the laminated material forming the tubular body of the container comes into direct contact with the liquid, the liquid permeates into the paper from the end face, and functions such as strength of the container cannot be satisfied. Sometimes. So, for example,
As shown in Japanese Patent Laid-Open No. 3-264344, a tape (3) made of a polyolefin film such as polyethylene was attached to the attachment portion of the body to prevent the liquid from penetrating into the paper (see FIG. 3). However, gas such as oxygen may penetrate from the outer plastic layer to the paper layer (4) and further through the tape, and may come into contact with the gas such as oxygen to have an adverse effect such as deterioration. In that case, for example, as shown in FIG. As shown, an aluminum vapor deposition layer (6) on the polyethylene film (5)
The tape (7) having the structure in which the above was formed was attached. However, when aluminum is used in either aluminum foil or aluminum vapor deposition, it must be treated as an incombustible material, which causes environmental problems. In this way, the reality is that there is no perfect one.

[0003]

SUMMARY OF THE INVENTION In view of the above situation, the present invention provides a gas barrier paper container that improves the gas barrier property without penetrating liquid into the paper and has a small effect on the environment. With the goal.

[0004]

SUMMARY OF THE INVENTION The present invention has been conceived to solve the above problems, and is a tube in which end portions of a sheet material made of a laminate including paper, plastic, and a gas barrier layer are bonded to each other. It is characterized in that a tape made of a film having a gas barrier layer is attached to the inside of a portion having the end portions attached to each other in a container having a cylindrical body portion.

The present invention will be described in detail below.

The stack forming the body of the container of the present invention is shown in FIG.
As shown in Fig. 1, the low-density porosity
Polyethylene (LDPE) (11) / Silicon oxide (12)
Si _XO / LDPE (13) / Paper (14) / LDPE
It has a layer structure of (15), and the end portion of this laminated body
Polyethylene (PE) inside the part where the two are stuck together
A film provided with a layer of silicon oxide (17) on both sides of (16).
Use tape (18) made of rum, and put the end face of the laminated body in a U shape.
It is heat-bonded so as to cover it. Here in the amorphous
Which indicates the glass transition temperature and residual entropy
That is. The glass used in the present invention is silicon oxide.
(Si_XO_y), Metal oxides (Al_XO_y, Mg
_XO_y, X = 1 to 2, y = 1 to 7). In addition,
How to attach the tape (18) is not U-shaped, but shown in FIG.
You can stick it so that it straddles the overlapping part of the end
Yes.

[0007]

According to the present invention, a container having a cylindrical body portion formed by laminating ends of a sheet material composed of a laminate including paper, plastic, and a gas barrier layer is placed inside the portion where the ends are laminated. By sticking a tape made of a film having a gas barrier layer, the gas such as oxygen that has permeated the polyolefin layer of the body is blocked by the gas barrier layer of the tape, and enters the container from the end face of the bonded part of the body. The invasion of gas such as oxygen is prevented. Further, since the gas barrier layer is also present in the portion other than the bonded portion of the body portion, invasion of gas such as oxygen into the container is prevented.

Moreover, the gas barrier layer used in the tape for sticking the ends of the sheet material composed of the body and the laminated body of the container to each other is made of an inorganic oxide such as silicon oxide, aluminum oxide or magnesium oxide. Therefore, after the container is used, it can be completely incinerated and discarded, and it does not adversely affect the environment as waste.

[0009]

【Example】

<Example 1> From the inner surface, low-density polyethylene 60 μm / silicon oxide vapor deposition layer 400Å / low-density polyethylene 20 μm /
Filling a 200 ml flat-top paper container consisting of 320 g / m ^{2 of} paper / 20 μm of low-density polyethylene with green tea,
Molded. Silicon oxide is a mixture of SiO and SiO ₂ . As shown in FIG. 3, the side end surface of the molded container has a low density polyethylene of 20 μm / silicon oxide vapor deposition layer of 500Å /
A strip film made of low-density polyethylene 20 μm is attached. After incubating at 25 ° C. or 60 ° C. for 4 weeks (keeping temperature, humidity, and other environmental conditions constant), the amount of vitamin C was measured by the indophenol method. The results are shown in (Table 1).

<Embodiment 2> Low density polyethylene 60 μm / silicon oxide coated polyethylene 12 μ from the inside
Green tea was filled and molded in a 200 ml capacity flat-top type paper container made of m / paper 320 g / m ² / low-density polyethylene 60 μm. Silicon oxide is a mixture of SiO and SiO ₂ . The side end surface of the molded container is low-density polyethylene 20 μm / silicon oxide coated polyethylene 20 μ
A strip film made of m is attached. Two
After incubating at 5 ° C or 60 ° C for 4 weeks, the amount of vitamin C was measured by the indophenol method. The results are shown in (Table 1).

<Comparative Example 1> From the inner surface, low-density polyethylene 60 μm / paper 320 g / m ² / low-density polyethylene 20
μm / ethylene methacrylic acid copolymer 15 μm / aluminum foil 7 μm / polyethylene 20 μm low density polyethylene 2
A green tea was filled in a 200 ml flat-top type paper container of 0 μm and molded. The side end surface of the molded container is laminated with a strip film of low-density polyethylene 40 μm as shown in FIG. 4 at 25 ° C or 60 ° C
After incubation for a week, the amount of vitamin C in green tea was measured by the indophenol method. The results are shown in (Table 1).

<Comparative Example 2> From the inner surface, low-density polyethylene 60 μm / paper 320 g / m ² / low-density polyethylene 20
μm / ethylene methacrylic acid copolymer 15 μm / aluminum foil 7 μm / polyethylene 20 μm low density polyethylene 2
A green tea was filled in a 200 ml flat-top type paper container of 0 μm and molded. The side end surface of the molded container is shown in FIG.
A strip tape composed of low-density polyethylene 20 μm / aluminum vapor deposition 400 liters / low-density polyethylene 20 μm as shown in FIG. 25 ℃ or 60 ℃
After 4 weeks of incubation at room temperature, the amount of vitamin C in green tea was measured by the indophenol method. The results are shown in (Table 1).

[0013]

[Table 1]

As can be seen from (Table 1), (Example 1)
When (Comparative Example 1) is compared with (Comparative Example 1), a large difference is found in the amount of vitamin C reduction, particularly at 60 ° C., and the present invention is superior in quality retention performance. In addition, when (Example 1) and (Comparative Example 2) are compared, the amount of vitamin C reduction does not change so much, and the product of the present invention is advantageous from the viewpoint of environmental problems. Further, no significant difference is found between (Example 1) and (Example 2).

<Example 3> Low density polyethylene from the inner surface
60μm / silicon oxide deposition 400Å / low density polyethylene
20 μm / paper 320 g / m²/ Low-density polyethylene 2
A 200ml flat top paper container consisting of 0μm
Molded. Silicon oxide is SiO, SiO ₂With a mixture of
is there. As shown in Fig. 3, the side edge of the molded container has a low density.
Degree polyethylene 20μm / silicon oxide vapor deposition layer 500Å /
Strip fill consisting of low-density polyethylene 20 μm
Are pasted together. Oxygen permeation at 25 ℃ and 60 ℃
The degree was measured by gas chromatography. The results (table
2).

<Embodiment 4> From the inner surface, low-density polyethylene 60 μm / silicon oxide coated polyethylene 12 μ
A 200 ml flat top type paper container composed of m / paper 320 g / m ² / low density polyethylene 60 μm was molded. Silicon oxide is a mixture of SiO and SiO ₂ .
The side end surface of the molded container is low-density polyethylene 20 μm /
A strip film made of silicon oxide-coated polyethylene 20 μm is attached. Oxygen permeability at 25 ° C and 60 ° C was measured by gas chromatography. The results are shown in (Table 2).

<Comparative Example 3> From the outer surface, low-density polyethylene 60 μm / paper 320 g / m ² / low-density polyethylene 20
200 consisting of μm / ethylene methacrylic acid copolymer 15 μm / aluminum foil 7 μm / low density polyethylene 20 μm
An ml flat top paper container was molded. The side end surface of the molded container is a low density polyethylene 4 as shown in FIG.
A 0 μm strip film is attached. 25
Oxygen permeability at 0 ° C and 60 ° C was measured by gas chromatography. The results are shown in (Table 2).

<Comparative Example 4> From the outer surface, low-density polyethylene 60 μm / paper 320 g / m ² / low-density polyethylene 20
200 consisting of μm / ethylene methacrylic acid copolymer 15 μm / aluminum foil 7 μm / low density polyethylene 20 μm
A ml flat top paper container was molded. The side end surface of the molded container is a low density polyethylene 2 as shown in FIG.
0μm / aluminum deposition 400Å / low density polyethylene 20
A strip tape of μm is attached. Two
Oxygen permeability at 5 ° C and 60 ° C was measured by gas chromatography. The results are shown in (Table 2).

[0019]

[Table 2]

As can be seen from Table 2, (Example 2)
Comparing (Comparative Example 3) and (Comparative Example 3), a large difference is observed in the oxygen permeability particularly at 60 ° C. Further, when (Example 2) and (Comparative Example 4) are compared, there is no significant difference in oxygen permeability, but it is advantageous to use the product of the present invention because of environmental problems.

In each of the above embodiments, the case of a flat top type paper container has been described, but the shape and structure of the container are not limited to this, and a so-called gable top type container may be used. Or, attach a bottom member and a lid member to the upper and lower open ends of the cylindrical or polygonal tubular body.
A container having a fixed structure may be used. In short, the container may have a structure in which the end face protection tape is attached to the portion of the body of the paper container where the ends are attached together.

[0022]

Since the present invention has the above constitution,
It is possible to make paper containers that have excellent gas barrier properties, excellent quality retention functions, and little impact on environmental problems. Also,
Since various inorganic oxides can be selected and used according to the usage (contents) of the container and the usage of the container, that is, depending on the required degree of gas barrier properties, the application range is wide.

[0023]

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of an example of a paper container of the present invention.

FIG. 2 is a sectional view showing a main part of another example of the paper container of the present invention.

FIG. 3 is a cross-sectional view showing a main part of a conventional paper container.

FIG. 4 is a cross-sectional view showing a main part of another example of a conventional paper container.

[Explanation of symbols]

 11, 13, 15: Low density polyethylene 12, 17: Silicon oxide vapor deposition layer 14: Paper 16: Polyethylene 18: Tape

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sumi Kobayashi 1-5-1 Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd.

Claims (4)

[Claims] 1. A container having a tubular body portion in which end portions of a sheet material made of a laminate including paper, plastic, and a gas barrier layer are attached to each other, and an inorganic material is provided inside the portion where the end portions are attached to each other. A gas barrier paper container, comprising a tape made of a film having a gas barrier layer made of an oxide. 2. The gas barrier paper container according to claim 2, wherein the inorganic oxide is silicon oxide. 3. The gas-barring paper container according to claim 2, wherein the inorganic oxide is aluminum oxide. 4. The gas-barring paper container according to claim 2, wherein the inorganic oxide is magnesium oxide.