JP2005335739A - Container inner bag and method for using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a container inner bag having a sufficient strength with a smooth flange surface free from any wrinkles or the like, and a method for using the same. <P>SOLUTION: The container inner bag 1 is formed of a synthetic resin film. A filling port and/or a discharging port of the container inner bag 1 has a flange part 2 of a three-layer structure in which the synthetic resin film to form the container inner bag 1 forms a core layer 21, and synthetic resin sheets 22 and 22' are stuck thereto to hold the core layer 21 from both sides. In the method for using the container inner bag 1 to be attached to a container, the flange part 2 of the container inner bag 1 is attached to the flange part of the container and sealed, and air between an inner surface of the container and the inner bag 1 is discharged in a negative pressure state to prevent the inner bag 1 from falling down. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a container inner bag used in a mounted state in a shipping container capable of transporting paint, food and other fluids (hereinafter referred to as contents) and a method of using the same.

  Conventionally, in the case of a shipping container that is used with the container inner packaging attached, when the contents of the inner bag are used up, the inner bag is collected from the container body (hereinafter referred to as a container). The loose lining method that can be replaced improves the versatility of the container and reduces the burden of the cleaning operation so that the inner surface of the container is not contaminated with the contents. However, the inner surface of the container and the inner bag tend to be inadequate, and in the case of stored items that need to be stirred at the time of injection or discharge, the inner bag falls off from the inner surface of the container during stirring and becomes a stirrer. There was a risk of wrapping, damage to the inner bag and the stirrer.

In order to solve such a problem, Patent Documents 1, 2, and 3 propose methods in which a vacuum is maintained between the inner bag and the inner surface of the container to prevent the inner bag from falling off. However, this method has a problem that it is necessary to mount equipment such as a vacuum pump on the container.
On the other hand, the inner bag is removed by supplying pressure fluid into the inner bag without using a vacuum pump, exhausting the air between the inner bag and the container from the exhaust port and pressing the inner bag against the inner surface of the container. A method of reliably preventing is described in Patent Document 4. In this case, it is possible to prevent the inner bag from falling off without using a vacuum pump, etc., but if the space between the container and the inner bag is not completely sealed, air will enter from there to prevent it from falling out. Since it becomes impossible, the flange part of the inner bag must be smooth and have excellent sealing performance.

  As a method for forming a flange portion in a plastic bag, for example, Patent Document 5 describes that a flange-shaped nozzle formed in advance is heat-sealed and connected to a bag body film. However, this method has a problem that since the portion where the flange is joined to the film is flat, it can be easily attached to a film on a flat surface but cannot be applied to an inner bag having a curved surface. . Further, Patent Document 6 describes that a flange part formed in advance is inserted into the tip of a tube-shaped pouring / discharging cylinder and is heat-sealed. In this case, since the flange parts are fused so as to receive a force in the load direction, there is a problem that the inner bag comes off from the heat-sealed portion when a large amount of contents are filled.

  In order to solve the problems as described above and attach the flange to the inner bag with sufficient strength to withstand the load, it is optimal to process the synthetic resin film used for the inner bag as it is, but in that case the flat surface However, since a smooth flange surface cannot be formed and soot tends to enter, there is a problem that when it is attached to a container of the above method, it cannot be attached in a state where air enters from the part of the soot and the shape of the inner bag is maintained. It was.

JP-A-7-206084 JP 7-215395 A JP 7-291392 A Japanese Patent Laid-Open No. 2003-104489 JP 2001-33341 A JP 2001-80695 A

  The present invention solves the above-mentioned problems and has a sufficient strength because the synthetic resin film forming the container inner bag is processed as it is into the flange portion, and has a smooth flange surface free from wrinkles and the like. It is an object to provide a container inner bag and a method of using the same.

As a result of intensive research, the inventors have sandwiched a synthetic resin film forming a container inner bag between two synthetic resin sheets, the synthetic resin film is a core layer, and the two synthetic resin sheets are each an outer layer. It has been found that a three-layer structure can easily form a flange portion having a smooth surface, and the present invention has been achieved.
That is, the present invention
(1) In a container inner bag 1 made of a synthetic resin film, the inlet and / or outlet of the container inner bag 1 is a synthetic resin film that forms the container inner bag 1 as a core layer 21, and the core layer 21 is disposed on both sides. A container inner bag 1 having a flange portion 2 having a three-layer structure formed by adhering synthetic resin sheets 22 and 22 'so as to be sandwiched therebetween.
(2) The container inner bag 1 according to (1), wherein the flange portion 2 is obtained by heat-sealing a core layer 21 made of synthetic resin and synthetic resin sheets 22 and 22 '.
(3) The flange portion 2 of the container inner bag 1 described in (1) or (2) is attached and sealed to the flange portion of the container, and then the air between the container inner surface and the inner bag 1 is discharged to The present invention relates to a method for using the container inner bag 1, which is mounted on a container of a type that prevents the inner bag 1 from falling off by setting the pressure state.

  Since the container inner bag 1 of the present invention uses the synthetic resin film forming the container inner bag 1 as one component of the flange portion 2, even if the flange portion 2 and the inner bag 1 are filled with the contents, the load There is no problem of falling off. In addition, since a smooth flange surface can be formed, it has sufficient hermeticity and airtightness. Furthermore, since it is only necessary to attach a synthetic resin sheet, it is easy to manufacture, and it is not necessary to form flange parts that match the shape of each container, so that it can be provided at low cost. doing.

The best mode for carrying out the present invention will be described below.
The container inner bag 1 of the present invention is made of a synthetic resin film. Synthetic resin films include polyethylene resins such as low density polyethylene, linear low density polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer, ethylene- (meth) acrylate ester copolymer, polypropylene, ethylene- Use a single layer or multilayer film obtained by mixing or mixing synthetic resins such as polyolefin resins typified by polypropylene resins such as propylene copolymers, polyamide resins, polyester resins and polystyrene resins. Can do. Further, it is of course possible to use a synthetic resin bonded with a reinforcing material such as a woven fabric, a non-woven fabric, or a burif. Among these, it is particularly preferable to use a single layer film of a polyethylene resin excellent in processability and chemical resistance, or a multilayer film in which the innermost layer is made of a polyethylene resin. The thickness of the synthetic resin film is preferably about 80 to 250 μm.

  The container inner bag 1 of the present invention is formed from the above-described synthetic resin film, but its shape is used as an inner bag of the container, and the preferred method of use is air between the inner surface of the container and the inner bag. In view of maintaining the negative pressure state by discharging the liquid, it is preferable to have a shape that matches the internal shape of the container. Therefore, as an example of a preferable method for manufacturing the container inner bag 1, after heat-sealing a predetermined portion of a tube-shaped synthetic resin film having gusset portions on both sides as shown in FIG. The main body of the container inner bag 1 is formed by cutting.

In addition, the flange part 2 of the container inner bag 1 is formed as follows, for example.
First, as shown in FIGS. 1 (A) and 1 (B), the tube width of the synthetic resin film at the portion where the flange portion 2 needs to be formed gradually increases among the inlet and outlet of the container inner bag 1. (In FIG. 1, there are two locations, the upper opening 11 and the lower opening 12 in FIG. 1). Next, the widened portion is widened to form a flange. At that time, considerable wrinkles are generated, but it is directly formed into a flange. After that, the flanged portion is used as the core layer 21, and then the core layer 21 is bonded so as to be sandwiched between the synthetic resin sheets 22 and 22 'to form the flange portion 2. Therefore, the obtained flange portion 2 is formed of a synthetic resin film continuous from the main body of the container inner bag 1 as the core layer 21 as is apparent from FIG. It has a strong strength. Furthermore, since the core layer 21 in which wrinkles are generated is sandwiched between the synthetic resin sheets 22 and 22 ′, the flange portion 2 having a smooth surface is obtained, and the container inner bag 1 having excellent sealing performance is obtained.

  In addition, as a method of adhering the core layer 21 made of the synthetic resin film and the synthetic resin sheets 22 and 22 ′, a method using an adhesive is of course possible, but it is particularly preferable to adhere by heat fusion. Even if there is a flaw in the core layer 21 by heat-sealing, the core layer 21 is melted by heat at the time of heat-sealing to smooth the whole and improve the sealing performance, and also has excellent chemical resistance on the adhesive surface. Therefore, there is an advantage that the adhesive strength is also good.

In addition, as the synthetic resin sheets 22 and 22 ′ used for forming the flange portion 2, the synthetic resin used when manufacturing the above-described synthetic resin film can be used without any particular limitation. In order to improve the adhesion and the adhesion, it is preferable that at least the sealing surface is made of the same material as the synthetic resin film.
Further, in the present invention, the thickness of the synthetic resin sheet is preferably not less than a certain degree in view of imparting smoothness and sealing properties by bonding the synthetic resin sheets 22 and 22 ′, and usually the thickness is 100 μm to 2 μm. It is preferable to use one having a thickness of about 0.0 mm.

A tube-shaped film made of linear low-density polyethylene and having a width of 2060 mm and a thickness of 150 μm is folded into 515 mm on each side to form a tube-shaped film with a width of 1030 mm. After forming the seal part 3, the outside of the heat seal part 3 is cut off to form the main body part of the container inner bag 1 shown in FIG. In this state, the portion corresponding to the flange portion 2 of the inlet and outlet of the container inner bag 1 is formed from the upper opening portion 11 and the lower opening portion 12 whose tip ends are widened. If it is spread as it is, it becomes a structure as shown in FIG. 2, and it becomes a shape like a funnel instead of a flange.
Further, the funnel-shaped part is expanded (in this case, the wrinkles are easier), and is formed into a flange-like shape. The flange part 2 which has the cross-sectional structure of FIG. 3 was formed by heat sealing.

The obtained container inner bag 1 is put into a vacuum pressure bonding lining container (an inner bag pressure bonding IBC made by Nissin General Building Materials), and the flange portion 2 of the inner bag is attached to the manhole port of the container and the flange surface of the discharge port. Tightened and sealed using an O-ring. After that, by blowing compressed air into the container inner bag 1 to inflate the container inner bag 1, the air existing between the container inner bag 1 and the container inner surface is discharged from the air vent, and then the air vent is opened. Closed and held under negative pressure. As a result, the container inner bag 1 was in close contact with the inner surface of the container and did not fall off.
Next, the container inner bag 1 was filled with the desired contents, but since the flange portion 2 was integrated with the main body portion of the container inner bag 1, the flange portion 2 was not dropped or broken by a load. Further, even if the contents are considerably used and the contents in the container inner bag 1 are reduced, the flange surface of the flange portion 2 is smooth, so that air enters from the sealed portion and the container inner bag 1 falls off. Was also not seen.

  The container inner bag 1 of the present invention can be suitably used as an inner bag of a container of a vacuum pressure bonding lining container type.

It is explanatory drawing explaining an example of the manufacturing method of the container inner bag 1 of this invention. (A) is before cutting off the outside of the heat seal portion, and (B) is after cutting off. It is a partially notched perspective view explaining the inlet port part before forming the flange part 2 of the container inner bag 1 of this invention. It is sectional drawing explaining the structure of the flange part 2 of the container inner bag 1 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Container inner bag 11 Upper opening part 12 Lower opening part 2 Flange part 21 Core layer 22, 22 'Synthetic resin sheet 3 Heat seal part

Claims (3)

In the container inner bag 1 made of a synthetic resin film, the inlet and / or outlet of the container inner bag 1 is a synthetic resin film that forms the container inner bag 1 as a core layer 21, and the core layer 21 is sandwiched from both sides. A container inner bag 1 having a three-layered flange portion 2 formed by bonding synthetic resin sheets 22 and 22 'to each other. The container inner bag (1) according to claim 1, wherein the flange portion (2) is obtained by heat-sealing a core layer (21) made of synthetic resin and synthetic resin sheets (22, 22 '). The flange part 2 of the container inner bag 1 according to claim 1 or 2 is attached to the flange part of the container and sealed, and then the air between the container inner surface and the inner bag 1 is discharged to make a negative pressure state. A method for using the container inner bag 1, wherein the container inner bag 1 is attached to a container that prevents the inner bag 1 from falling off.

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