JP2002193326A - Inner bag for liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inner bag for a liquid which can contain a highly alkaline liquid such as a repellent for floors or a detergent dedicated for oil and fat in addition to a variety of liquids such as chemicals, beverages and seasonings wherein respective layers are peeled and there is no fear of a liquid leakage from the inner bag or the bag breaking and there is no need of laminating via an adhesive or the like which is susceptible to alkaline liquids. SOLUTION: The inner bag 20 for a liquid which is to be fitted in an outer box 40 made of a paper board, a corrugated fiberboard or the like and is equipped with an appropriate spout 30. The inner bag comprises a linear low density polyethylene(LLDPE) film 21, a nylon(Ny) coextrusion film 22 comprising an LLDPE layer 3, a Ny layer 4 and an LLDPE layer 5 and an LLDPE film 23, which are thermally welded by extrusion-laminating the LLDPE films 21 and 23 for lamination.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outer box 40 made of paperboard or corrugated cardboard which can store a strongly alkaline liquid material such as a floor release agent or a detergent exclusively used for fats and oils. The present invention relates to a liquid inner bag that does not need to be laminated via an adhesive layer or the like to be attached.

[0002]

2. Description of the Related Art As shown in FIG. 1B, a liquid material such as a medicine, a beverage or a seasoning can be widely accommodated in an outer box 40 made of paperboard or corrugated paper. 2. An inner bag 20 for liquid to which a spout 30 is attached, as shown in FIG.
1, a film-like LLDPE layer 3 and a Ny layer 4 respectively
And the LLDPE layer 5 are laminated by dry lamination via urethane-based adhesive layers 7 and 8 of about 2 g / m ² , and the strength, oil resistance, chemical resistance, oxygen barrier property and the like are obtained. An excellent Ny laminated film 25 of 20 to 40 μm, and an LLDPE film 23 of 30 to 50 μm, which is also excellent in heat fusion property, water resistance, chemical resistance and the like,
An inner bag for liquid in which the LLDPE films 21 and 23 are extruded and laminated by lamination is generally widely used.

Conventionally, as shown in FIG. 2, the above-described LLDPE film 21, Ny laminated film 25, and LLDPE film 23 are laminated on the inner surface of a laminated film 20 with adhesives 7 and 8, respectively. 50-100μm with excellent strength, heat fusion, water resistance and chemical resistance
In general, an inner bag for liquid in which the LLDPE films 24 are superposed and arranged and the peripheral portion is heat-sealed a to form a bag is generally used.

[0004]

However, the conventional liquid inner bag having a laminated structure shown in FIG. 2 is a liquid inner bag excellent in water resistance, oil resistance, chemical resistance, etc. When a strong alkaline liquid with a pH of 13 or more is stored and stored for a long period of time, such as a peeling agent for cleaning or a detergent exclusively for fats and oils, the surfactants and amines contained in the strong alkaline liquid come into contact with the liquid. The LLD of the Ny laminated film 25 located on the inner surface side is diffused or permeated into the LLDPE film 24 at the molecular level, and further located outside the LLDPE film 24.
The adhesive layer 7 permeates the PE film 21 and the LLDPE layer 3 sequentially, deteriorating the adhesive layer 7, and the LLDPE layer 3 on the inner surface side.
And the Ny layer 4 may be peeled off, which may cause leakage of the liquid inner bag or breakage of the bag.

Incidentally, an adhesive which is hardly affected by a strong alkaline liquid material has not yet been developed, and each of the adhesives is in the form of a film without passing through the above-mentioned urethane-based adhesive layers 7 and 8. When the LLDPE layer 3, the Ny layer 4, and the LLDPE layer 5 are laminated by extruding the LLDPE layers 3, 5 onto the Ny layer 4 and laminating them by heat fusion, the NLD layer 4, the LLDPE layers 3, 5 Insufficient heat-sealing properties often resulted in delamination between layers, causing liquid leakage, bag breakage, and the like.

Accordingly, an object of the present invention is to accommodate, in addition to a wide range of liquid substances such as medicines, beverages and seasonings, especially strong alkaline liquid substances such as floor release agents and detergents exclusively used for fats and oils. Outer box 4 made of paperboard, cardboard, etc.
It is an object of the present invention to provide a liquid inner bag which is mounted in the inner bag and which is free from the possibility that the respective layers are peeled off from each other to cause liquid leakage or breakage of the liquid inner bag.

[0007]

According to the first aspect of the present invention, there is provided a liquid inner bag 20 having an appropriate spout 30 attached thereto in an outer box 40 made of paperboard or cardboard. A linear low density polyethylene (LLDPE) film 21, an LLDPE layer 3, a nylon (Ny) layer 4, and an LL
Ny coextruded film 22 with DPE layer 5, LLDP
An inner bag for liquid, characterized in that the ELD film 23 and the LLDPE films 21 and 23 are laminated by extrusion lamination.

In the inner bag for liquid according to the present invention, as will be described in the embodiment described later, an LLD having excellent heat-fusibility and the like is provided.
PE film 21 and LLD in a hot-melted state respectively
A Ny co-extruded film 22 in which the PE layer 3, the Ny layer 4, and the LLDPE layer 5 are co-extruded and laminated and laminated;
The LLDPE films 21 and 23 in the state of being thermally melted, respectively, with the LLDPE film 23 having excellent heat fusion property and the like.
Are laminated by extrusion lamination, so that the respective layers are firmly laminated.
In the case where three or more strongly alkaline liquid substances are stored and stored for a long period of time, for example, surfactants and amines contained in the strongly alkaline liquid substance are mixed with the LLDPE film 21 on the inner surface side of the inner bag 20 for liquid. Even if it diffuses and penetrates into the LLDPE layer 3 at the molecular level, it is possible to provide an inner bag for liquid that does not cause separation between the respective layers to cause liquid leakage or breakage.

Next, the invention according to claim 2 of the present invention relates to the liquid inner bag according to claim 1 wherein the LLDPE
Film 21 and Ny coextruded film 22 and LLDPE
An inner bag for liquid, characterized in that an LLDPE film 24 is superposed and arranged on the inner surface side of a laminated film 20 on which a film 23 is laminated, and the peripheral portion is heat-sealed a to form a bag.

In the liquid inner bag of the present invention, the LLDP
E film 21, Ny coextruded film 22, and LLDP
On the inner surface side of the laminated film 20 on which the E film 23 is laminated, L having excellent strength, heat fusion property, water resistance, chemical resistance, and the like is provided.
By arranging the LDPE film 24 and forming a bag shape by heat-sealing the peripheral portion, the strength of the liquid inner bag 20 can be reinforced and the influence of a strong alkaline liquid material can be reduced.

[0011]

FIG. 1A is a partial cross-sectional view showing a laminated structure of a liquid inner bag according to an embodiment of the present invention, and FIG. It is sectional explanatory drawing which shows the mounted state.

The inner bag for liquid according to the embodiment of the present invention is an inner bag for liquid 20 shown in FIG. And the LLDPE film 21 as shown in FIG. 1A.
Of the LLDPE layer 3, the Ny layer 4, and the LLDPE layer 5
y The co-extruded film 22 and the LLDPE film 23 are laminated by extruding and laminating the LLDPE films 21 and 23 and heat-sealing, as shown in FIG. 1B. On the inner surface of the bag 20
The inner bag for liquid is formed by arranging the LLDPE films 24 one on top of the other and heat-sealing the peripheral portion to form a bag.

The outer box 40 in the present embodiment is a rectangular parallelepiped outer box having an inner volume of 0.5 to 20 liters (L) made of ordinary paperboard or corrugated cardboard. In the bag 20, a normal plastic molded spout 30 is passed through the inner bag 20, and the flange 31 of the spout 30 is attached to the inner surface of the inner bag 20 by heat fusion. As shown in FIG. 1B, for example, the inner bag 20 penetrates the spout 30 attached to the inner bag 20 for liquid through the side plate 41 of the outer box 40, and tightens the cap 32 of the spout 30.
The inner bag 20 for liquid can be mounted in the outer box 40 without any restrictions.

In the liquid inner bag of the present embodiment, Ny
The co-extruded film 22 has a heat-sealing property of 5-1.
A linear low-density polyethylene (LLDPE) layer 3 of about 0 μm, a nylon (Ny) layer 4 of 10 to 20 μm having excellent strength, oil resistance, chemical resistance, oxygen barrier property, etc. An excellent LLDPE layer 5 of about 5 to 10 μm is formed into a film from a T-shaped nozzle (referred to as a T-die) by interposing an adhesive resin layer (not shown) as necessary. While being extruded, heat-sealed firmly and laminated (called co-extrusion lamination).
フ ィ ル ム 40 μm film.

FIG. 1 shows an inner bag for liquid according to the present embodiment.
The LLDPE film 21, the Ny co-extruded film 22, and the LLDPE film 23 shown in A are 30 to 50 μm LLDPE having excellent heat fusion properties, water resistance, chemical resistance, and the like.
The film 21 and the Ny coextruded film 22 of 20 to 40 μm described above, which have excellent heat-fusing properties, strength, oil resistance, chemical resistance, oxygen barrier properties, and the like, and heat-fusing properties, water resistance, and chemical resistance The LLDPE films 21 and 23, which are each in a hot-melted state, are combined with the LLDPE films 21 and 23, which have excellent properties and the like, to which a slip agent of 30 to 50 μm is added.
By extruding into a film shape from a letter-shaped nozzle, it can be obtained by strong heat fusion.

The LLDPE film 24 disposed on the inner side of the laminated film 20 in the liquid inner bag of the present embodiment.
About 50 to 100 μm LL having excellent strength, heat-fusibility, water resistance, chemical resistance, etc.
DPE film 24.

In the inner bag for liquid according to the embodiment of the present invention, the LLDPE film 21, the Ny co-extruded film 22, and the LLDPE film 23, which have the above-mentioned excellent heat-sealing properties, are melted respectively. By extruding and laminating the LLDPE films 21 and 23, the layers are firmly heat-sealed and laminated. Therefore, even when a strong alkaline liquid having a pH of 13 or more is stored and stored for a long period of time, the respective layers may be laminated. Was peeled off, and an inner bag for liquid was obtained without fear of liquid leakage or breakage.

[0018]

As described above, in the inner bag for liquid according to the present invention, in addition to a wide range of liquids such as medicines, beverages and seasonings, the inner bag for liquids of the present invention, in particular, is used exclusively for floor release agents and oils and fats. Attached in an outer box 40 made of paperboard or corrugated cardboard, which can store a strongly alkaline liquid material such as a detergent. Each layer is peeled off and the inner bag for liquid leaks or breaks. It is possible to provide a liquid inner bag which does not need to be laminated via an adhesive layer or the like which is not likely to cause an influence of an alkaline liquid material.

[Brief description of the drawings]

FIG. 1A is a partial cross-sectional view showing a laminated structure of a liquid inner bag of the present invention, and FIG.
It is sectional explanatory drawing which shows the state mounted in 0.

FIG. 2 is a partial cross-sectional view showing a laminated structure of a conventional liquid inner bag.

[Explanation of symbols]

3, 5: Linear low-density polyethylene layer 4: Nylon layer
7, 8 ... Adhesive layer 20 ... Liquid inner bag 21, 23,24 ... Linear low-density polyethylene film 22 ... Nylon co-extruded film 25 ... Nylon laminated film 30 ... Outlet 31 ... Flange 32 ... Cap 40
... Outer box 41 ... Side plate a ... Heat-fused part

Claims (2)

[Claims] 1. An inner bag 20 for liquid, which is mounted in an outer box 40 made of paperboard or corrugated paper and has an appropriate spout 30 attached thereto.
A linear low density polyethylene (LLDPE) film 21, a Ny coextruded film 22 of an LLDPE layer 3, a nylon (Ny) layer 4, and an LLDPE layer 5, and an LL
DPE film 23 and LLDPE films 21 and 2
3. An inner bag for a liquid, wherein 3 is laminated by extrusion lamination. 2. The liquid inner bag according to claim 1, wherein
LDPE film 21 and Ny coextruded film 22 and L
An inner bag for a liquid, characterized in that an LLDPE film 24 is superposed and arranged on the inner surface side of a laminated film 20 on which an LDPE film 23 is laminated, and the periphery is heat-sealed a to form a bag.