JPS61189911A - Manufacture of tube with passage closing material - Google Patents

Abstract

PURPOSE:To bond a closing material firmly in any condition and at all times by a method wherein a passage closing material is fitted to a mandrel tip and the passage closing material is molded integrally with the shoulder part and the throat part of the tube and then the passage closing material and the bonded part between the shoulder part and the oral part are reheat-treated. CONSTITUTION:A passage closing material 2 composed of a closing part (a) and an expanding part (b) made of laminated material is fitted to the tip of a mandrel 1 and a barrel part 3 of laminated material covers the circumference. The tip part of the mandrel 3 is inserted into the cavity 5 of a split mold 4, synthetic resin 6 is supplied into the cavity 5 and hardened, and the throat part and the shoulder part are molded integrally with the barrel part 3 and the passage closing material 2. After synthetic resin is hardened, the molded piece is taken out of the split mold 4, and the throat part to the shoulder part of the piece is inserted into a high frequency coil 8 and reheated by high frequency induction heating. In this way, the passage closing material is bonded surely and can be broken through positively when it is used.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a tube with a passage closure material suitable for small containers for pharmaceuticals, cosmetics, chemical materials, etc.

2. Description of the Related Art Conventionally, as shown in FIG. 6, there is a tube 11 which is made of soft metal and has a closing portion a' in the oral passageway, which is torn with a needle during use to force out the contents. Since this type of product is made of soft metal, it has the disadvantage that the surface becomes uneven during extrusion, which impairs the appearance.

Therefore, as shown in FIG. 7, the body part 3 is constructed of a laminated synthetic resin tube, and the shoulder part 12 to the mouth part 13 are integrally formed into a tube made of a synthetic resin material such as polyethylene by plastic processing. It has been known. Since such a tube needs to be provided with the thread 7 on the outside of the mouth part 13 and is formed by plastic working, it cannot use a laminated material like the body part, and is made only of a synthetic resin material.

Therefore, unlike a laminated material, the area from the head 13 to the shoulder 12 has poor gas barrier properties, and oxygen, etc. may enter from these areas, and vaporized components of the contents may gradually leak, resulting in poor shelf life. damage. Therefore, as shown in FIG. 8, a laminate insert is provided inside the shoulder 12 to provide gas barrier properties. However, even with this, vaporized components may gradually leak through the mouth part and the cap, causing the contents to deteriorate.

Problems to be Solved by the Invention In view of the above-mentioned conventional problems, the present invention provides a method of attaching a closing material to the passageway at the mouth of the tube and closing it in order to prevent the leakage of vaporized components of the contents and the infiltration of air. When attaching materials, simply bonding them with heat will often result in poor adhesive strength, and if you try to break through the closure material and squeeze out the contents when using the tube, the closure material may be stuck deep inside the tube. There is a fear that the hole may not open or even if it does, it will only be a very small hole.

The following two points are considered to be the cause of this defect. One is that the mold for shoulder molding is forcedly cooled, so it is stable during continuous operation.

Immediately after starting operation at the start of work, and during continuous operation, stopping,
If the operation is repeated, the mold temperature will not be constant, and therefore the thermocompression bonding conditions will change, causing variations in adhesive strength. Particularly when the mold temperature drops, this can cause very weak adhesion.

Another reason is that if the plastic used for part of the shoulder and the plastic used for both the inner and outer surfaces of the closure material are not the same type, variations in mold temperature will have a large effect, and some may not adhere at all. things may occur.

Regarding these drawbacks, since many processes are processed in one molding machine, it is almost impossible to continue non-stop operation for a long time, and the closure material has poor moldability, lamination properties,
Chemical resistance is required, and on the other hand, the plastic from the shoulder part to the mouth part is required to have workability and stress crack resistance.We are looking for a plastic that can meet all of these conditions, among the same type of plastic. It is difficult to choose between them.

In view of the above points, the present invention aims to always firmly join closure members even under the following conditions.

A method for solving illumination points The present invention uses a synthetic resin material to integrally mold the body, shoulder, and mouth of the tube by plastic processing using a mold and a mandrel, and a passage closing material is added to the tip of the mandrel. By fitting and molding, the passage opening closing material is also molded integrally with the tube shoulder to mouth part, and after molding, the joint between the passage closing material and the shoulder part to the mouth part is reheated. This is a method for manufacturing a tube with a passage closing material.

In the above, for the body part and the passage closing material □, a laminated material made of metal foil, paper, etc. as a core material and a synthetic resin layer laminated thereon is preferably used, but a single layer or a laminated material made of only synthetic resin is preferably used. But that's fine. The passage closing material is shaped like a cup with a bottom, and the bottom is the part that closes the passage, and the other part extends from a part of the oral part, covers the inside of the shoulder part, and reaches near the tip of the trunk. be. To give an example of the material, the core material is aluminum bamboo, the inner surface is made of a chemical-resistant material, such as a synthetic resin layer such as polypropylene, and the joining side is made of a synthetic resin layer, such as a polyethylene layer, that is easily bonded to the mouth and shoulder parts. Some are constructed from laminated materials.

Further, as a synthetic resin material that is plastically worked from the shoulder portion to the mouth portion, for example, polyethylene can be mentioned.

When the working tube is plastically worked from the shoulder to the mouth, the passage closing material is joined at the same time, and the joint is further strengthened by reheating.

Embodiment To explain the embodiment based on the drawings, a passage closing member 2 made of a laminated material and consisting of a closing part a and a widening part as shown in FIG. 2 is fitted onto the tip of a mandrel 1. Further, a trunk section 3 made of laminated material is inserted around the periphery. The tip of the body 3 projects somewhat from the shoulder of the mandrel 1.

Next, as shown in FIG. 3, the tip of the mandrel 3 as described above is inserted into the cavity 5 of the split mold 4, and the cavity 5 is filled with a synthetic resin 6 and hardened to form the body 3, The mouth part and the shoulder part are integrally molded together with the passage closing material 2.

At this time, a thread 1 is simultaneously formed on the outside of the mouth of the tube.

After the synthetic resin has hardened, the molded product is removed from the split mold 4, and
As shown in the figure, the molded product is inserted into a high-frequency coil 8 from the mouth to the shoulder, and this portion is reheated by high-frequency induction heating.

This reheating treatment may be performed after fitting the cap onto the product, or may be performed in a separate step after taking the product out of the molding machine.

FIG. 5 is a partially sectional front view of the product of the present invention with the cap 9 fitted.

If the reheating treatment is not performed, the joint state of the joint between the mouth part 13 and the passage closing material 2, especially at the corner part 10, will not be constant, and if you try to pierce the closing part a with a needle during use, the corner part Although the passage closing member 2 may peel off from the passageway closing member 10 and fall inward, this does not occur in the present invention, and the passage closing member 2 can always break through the closing portion a.

Effects of the Invention The present invention is a synthetic resin tube, and a passage closing material is provided at the mouth part to prevent the contents from deteriorating, and the passage closing material is reliably joined and can be reliably pierced during use. You will get a tube that can be used.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the passage closing material and the body attached to the mandrel, FIG. 2 is a perspective view of the passage closing material, and FIG. Fig. 4 is a cross-sectional view during reheating treatment,
FIG. 5 shows a partial sectional view of the product, and FIGS. 6 to 8 show sectional views of the leading tube. 1... Mandrel 2... Passage closing material 3... Body 4... Divided mold 5...
...Cavity 6...Synthetic resin 7...
...Screw thread 8...High frequency coil 9...
Cap 10...Corner part 11...
・Tube-12... Shoulder part 13... Mouth part 14... Laminated material insert a, a''...
...Closing part b... Expanding part Patent applicant
Nissho Printing Co., Ltd. Agent Patent Attorney Hide Komatsu Agent Patent Attorney Hiroo Asahi Nisai 2 Figures 4 Figures 5 Figures

Claims (1)

[Claims] Using a synthetic resin material, when molding the body, shoulder, and mouth of the tube integrally by plastic processing using a mold and a mandrel, by fitting a passage closing material to the tip of the mandrel and molding, A method for producing a tube with a passage closing material, characterized in that the passage closing material is also molded integrally with the shoulder to mouth part of the tube, and after molding, the joint between the passage closing material and the shoulder to mouth part is reheated. .