JP7619990B2 - Barrier member, container, and method for manufacturing the container - Google Patents

Description

The present invention relates to a barrier member, a container using the same, and a method for manufacturing the container.

Conventionally, containers for storing caulking materials, adhesives, etc. have been used that have a canopy with an opening at the end of a cylindrical body. In order to maintain the quality of the contents, such containers often have a membrane (a film-like body that blocks the opening of the canopy) on the inside that functions as a barrier member. For example, Patent Documents 1 to 3 disclose cartridges that are formed so that the contents can be pushed out by a plunger and that have a membrane.

By providing a membrane, the opening can be sealed when the container is unopened, maintaining the quality of the contents in good condition, while when in use, the membrane can be broken to open the opening and release the contents. In particular, caulking materials and adhesives tend to harden or deteriorate when exposed to moisture or air, so it is extremely important to use a membrane to completely seal the opening and ensure barrier properties (the ability to prevent the intrusion of gases, moisture, etc.).

Patent No. 4665951 Patent No. 4919563 Patent Publication No. 2015-500776

In order to ensure the barrier properties of a container using a membrane, it is effective to ensure that the area covered by the membrane is sufficient. However, in conventional containers, the area covered by the membrane is limited to the inner wall of the canopy, and in cases where a relatively high barrier property is required, this type of configuration may result in insufficient barrier properties.

In view of the above-mentioned problems, the present invention aims to provide a barrier material that makes it easier to obtain higher barrier properties in a container, a container using the same, and a method for manufacturing the container.

The barrier member according to the present invention is a barrier member that is provided inside a container body having a canopy with an opening provided at the front side of a cylindrical body so as to close the opening, and is configured to have a canopy-corresponding part that covers the inner wall of the canopy, and an extension part that extends rearward from the outer periphery of the canopy-corresponding part and covers the vicinity of the front end of the inner wall of the body.

This configuration makes it easier to obtain higher barrier properties in the container. Note that the front-to-rear direction here is merely determined for the sake of convenience so as to coincide with the axial direction of the cylindrical body portion, and the side on which the canopy is provided as viewed from the body portion is considered to be the front side.

In addition, in the barrier member having the above configuration in which the portion near the outer periphery of a flat membrane is bent backward, the extension may be formed by the portion near the outer periphery, and the canopy-corresponding portion may be formed by the inner portion of the portion near the outer periphery. With this configuration, it is possible to easily form the barrier member using the membrane.

The container according to the present invention has the barrier member and the container body of the above configuration, and the canopy-corresponding portion and the extension portion are fixed to the container body. In addition, in the container of the above configuration for containing a fluid, a plunger may be movably provided to close the rear side of the container body, and after the barrier member is broken and the opening is opened, the fluid may be released through the opening by being pushed out by the plunger.

The manufacturing method according to the present invention is a manufacturing method in which the above-mentioned adhesion is achieved by fusing through heating.

More specifically, the above manufacturing method may be a manufacturing method in which one or more protrusions are provided on the inner wall of the canopy portion, and the heating is performed while the barrier member is pressed against the protrusions. With this method, it is possible to achieve particularly reliable and sufficient fusion at the protrusions.

More specifically, the above manufacturing method may be a manufacturing method in which the convex portion is formed in a ring shape surrounding the opening. According to this method, by achieving reliable fusion at least in the portion of the convex portion, the container body can be reliably sealed. More specifically, the above manufacturing method may be a manufacturing method in which the canopy portion and the body portion are integrally molded from resin to form the container body.

More specifically, the manufacturing method may be such that the barrier member has a conductive layer, and the heating is electromagnetic induction heating in which a current is passed through the conductive layer. With this method, the entire barrier member can be heated evenly and efficiently, and deformation or deterioration of the container body can be minimized.

The barrier member according to the present invention makes it easier to obtain higher barrier properties in a container. Furthermore, the container and method for manufacturing a container according to the present invention make it possible to enjoy the advantages of the barrier member according to the present invention.

FIG. 2 is a configuration diagram of a cartridge-type container CT according to the present embodiment. FIG. 2 is an explanatory diagram showing a sample example of a cartridge-type container CT. FIG. 2 is an explanatory diagram showing a sample example of the membrane 2 according to the present embodiment. 1A to 1C are explanatory diagrams relating to a manufacturing method of the cartridge-type container CT. FIG. 2 is a configuration diagram of the container body 1 according to the present embodiment as viewed from the rear. 1A to 1C are explanatory diagrams relating to a manufacturing method of the cartridge-type container CT. 1A to 1C are explanatory diagrams relating to a manufacturing method of the cartridge-type container CT.

The following describes an embodiment of the present invention with reference to the drawings. In this application, unless otherwise specified, the front-to-rear direction corresponds to the axial direction of the cylindrical body, and the side on which the canopy is provided is considered the front side when viewed from the body.

1. Configuration of the Cartridge-Type Container FIG. 1 is a schematic diagram of the cartridge-type container CT according to this embodiment. FIG. 1 (also in FIG. 4, FIG. 6, and FIG. 7 described later) is shown as a cross-sectional view of a case where the cartridge-type container CT is cut along a plane passing through the central axis of a body portion 11 formed in a cylindrical shape. In FIG. 1, the projection portion 12a1 described later is omitted. FIG. 2 shows the state of the membrane 2 and its surroundings in a cut example of a sample of the cartridge-type container CT. As shown in these figures, the cartridge-type container CT is formed using a container body 1, a membrane 2 (one form of the barrier member according to the present invention), a plunger 3, and a barrier film 4, and is used as a container for containing a fluid (content) such as a caulking material or an adhesive.

The container body 1 is configured with a lid portion 12 having an opening OP provided at the front of a cylindrical body portion 11. In the container body 1, the lid portion 12 and the body portion 11 are integrally molded from resin, and the lid portion 12 and the body portion 11 are seamlessly connected. Polyethylene or the like is suitable as the resin from which the container body 1 is formed. For example, the size of the container body 1 that holds about 330 ml of contents is set to a total length of about 200 mm, an outer diameter of about 50 mm, and a thickness of about 1 mm.

The canopy 12 is the portion of the container body 1 excluding the body 11 (the portion to the left of the dashed line α in FIG. 1), and is configured with a nozzle 12b that protrudes forward from the center front side of the disk-shaped portion 12a, whose axial direction is the front-to-rear direction. An opening OP that extends in the front-to-rear direction is formed in the center of the disk-shaped portion 12a and the nozzle portion 12b when viewed from the front, and connects the inside of the container body 1 to the outside when the membrane 2 is broken. The radial dimension of the opening OP is sufficiently smaller than the inner diameter of the body 11. The rear surface of the disk-shaped portion 12a is a plane with the front-to-rear direction as its normal line.

Membrane 2 is a thin film-like member provided inside container body 1 so as to cover opening OP, and is formed by laminating, for example, polyethylene terephthalate (PET) film, polypropylene (PP) film, aluminum foil, and polyethylene (PE) film. At least the outer surface of membrane 2 (the surface facing the inner wall of container body 1) is covered with a polyethylene layer. Figure 3 shows an example of a sample of membrane 2 according to this embodiment.

As shown in Figures 1 to 3, the membrane 2 has a canopy-corresponding portion 21 that covers the inner wall of the canopy portion 12, and an extension portion 22 that extends rearward from the outer periphery of the canopy-corresponding portion 21 and covers the front end vicinity of the inner wall of the body portion 11. The outer edge shape and dimensions of the canopy-corresponding portion 21 are set to match the rear surface of the disc-shaped portion 12a, and the extension length of the extension portion 22 is set to about 5 mm, for example. The extension length of the extension portion 22 can be set to any length, with a guideline of, for example, 30 mm or less.

The membrane 2 is formed by bending backwards a portion near the outer periphery of a flat film-like body (the laminate of aluminum foil and polyethylene described above) with a circular outer edge, with the extension 22 formed by this portion near the outer periphery and the canopy-corresponding portion 21 formed by the inner portion of this portion near the outer periphery. This makes it possible to easily form a roughly cup-shaped membrane 2 as shown in Figure 3 using the above film-like body.

The plunger 3 is a member formed in a cylindrical shape with a bottom, and is formed, for example, by providing an aluminum barrier layer on a polyethylene body, with an outer diameter set to be equal to or slightly larger than the inner diameter of the body 11. The plunger 3 is fitted into the rear open end of the body 11 with the bottom side facing forward. Grease is provided between the plunger 3 and the body 11 to reduce sliding resistance and allow the plunger 3 to move smoothly. This grease also serves to prevent the ingress and egress of gas, moisture, etc. in the gap between the plunger 3 and the body 11, and therefore functions as a lubricant with high barrier properties.

The barrier film 4 is provided so as to entirely cover the outer surface of the body 11, and is formed, for example, as a laminated film with a sandwich structure in which aluminum foil is sandwiched between plastic films. As described above, the membrane 2 and the barrier film 4 are thin films, but are laminated with aluminum foil, and have very high barrier properties. It is desirable that the barrier film 4 at least covers the area from the rear end of the body 11 to the same position as the position near the rear end of the extension 22 (i.e., the inside of the container body 1 is completely covered by at least one of the membrane 2 and the barrier film 4, except for the insertion point of the plunger 3).

When unopened, the cartridge-type container CT can maintain the quality of the contents by sealing the opening OP with the membrane 2, but when in use, the opening OP can be opened by breaking the membrane 2, allowing the contents to be released. When in use, the cartridge-type container CT can be set in a dedicated tool (e.g., a handgun), allowing the user to move the plunger 3 forward with a simple operation and easily push out an appropriate amount of the contents.

The cartridge-type container CT of this embodiment uses a membrane 2 having a canopy-compatible portion 21 and an extension portion 22. The canopy-compatible portion 21 is fused to the inner wall of the canopy portion 12 (the rear surface of the disk-shaped portion 12a) and covers this portion. The extension portion 22 is fused to the inner wall of the body portion 11 near the front end and covers this portion.

In this way, the membrane 2 does not only cover the inner wall of the canopy 12, but also continuously covers and is fused to the inner wall of the container body 1 through the corner portion 13 (the portion where the body portion 11 and the canopy 12 meet at a substantially right angle in the cross section shown in FIG. 1) formed at the boundary between the body portion 11 and the canopy 12, and reaches the area near the front end of the inner wall of the body portion 11. Therefore, the cartridge-type container CT of this embodiment is able to obtain higher barrier properties than when it is assumed that the membrane 2 covers and is fused only to the inner wall of the canopy 12. The verification results on this point (results of the contents preservation test) will be explained in detail later.

Furthermore, compared to the case where the membrane 2 covers and is fused only to the inner wall of the canopy portion 12, in this embodiment, a larger fusion area can be secured by fusion at the extension portion 22, and the membrane 2 also covers the corner portion 13, which is relatively prone to problems with barrier properties due to stress concentration, etc., so that it is advantageous in terms of barrier properties from these viewpoints as well. If the corner portion 13 has a roundness (R), etc., it is desirable for the membrane 2 to cover the entire roundness.

If we assume that the container body 1 is formed by rotational welding (welding by pressing one side against the other while rotating at high speed) of the canopy 12 to the body 11, the corners 13 corresponding to the fused parts will be thick and uneven, and it is not easy to cover the corners 13 and provide the membrane 2 appropriately. However, in this embodiment, the container body 1 is formed by integral molding, so the corners 13 do not become thick and uneven, and it is easy to cover the corners 13 and provide the membrane 2 appropriately.

In addition, in this embodiment, the membrane 2 continuously covers the inner wall of the container body 1 from the canopy 12 to the area near the front end of the body 11, so that at least one of the highly barrier membrane 2 and the barrier film 4 covers all parts of the container body 1 from the inside or outside, except for the rear end. In this way, in this embodiment, there are no parts where the resin of the container body 1 is exposed (parts that are not covered from either the inside or the outside), so the barrier properties are highly reliable.

As described above, the membrane 2 according to this embodiment is provided inside the container body 1, which has a canopy portion 12 having an opening OP provided at the front side of a cylindrical body portion 11, so as to cover the opening OP. Furthermore, the membrane 2 has a canopy corresponding portion 21 that covers the inner wall of the canopy portion 12, and an extension portion 22 that extends rearward from the outer periphery of the canopy corresponding portion 21 and covers the vicinity of the front end of the inner wall of the body portion 11. Therefore, as described above, by using the membrane 2, it is easy to obtain higher barrier properties in the cartridge-type container CT.

In order to verify the effectiveness of the membrane according to this embodiment, a content preservation test was carried out using samples. This will be explained below.

<Test conditions>
A sample of the cartridge-type container according to the present embodiment was formed by fusing a membrane with an extension part of different lengths to a container body molded by injection molding, attaching a plunger, and providing a barrier film on the entire outer periphery. The specific configuration of each member is as follows:
(1) Container body: Made of high-density polyethylene with a total length of 216 mm, outer diameter of 50 mm, and thickness of 1.15 mm.
(2) Membrane: formed by laminating a PET film (thickness 12 μm), a PP film (thickness 40 μm), an aluminum foil (thickness 40 μm), and a PE film (thickness 20 μm).
(3) Plunger: This was formed by laminating a PE film (thickness 25 μm) and aluminum foil (thickness 40 μm) on the rear side of the bottom surface (the side facing the outside of the container) of a bottomed cylindrical member made of high-density polyethylene with a total length of 20 mm, an outer diameter of 48 mm, and a thickness of 1 mm.
(4) Barrier film: formed by laminating a PET film (thickness 12 μm), an aluminum foil (thickness 9 μm), and a PE film (thickness 25 μm).
Regarding the membranes, three or more each of the membranes with extension lengths of 0 mm (i.e., a form in which no extension is provided), 3 mm, 7 mm, and 15 mm were prepared, and multiple containers were formed using each of the prepared membranes.

The containers formed as described above were filled with three different types of sealant as the contents, stored in an atmosphere with a temperature of 50°C and a relative humidity of 90%, and the state of the contents after one month was observed visually and by touch. The three different types of sealant used were a moisture-curing silicone-based sealant (hereinafter abbreviated as "silicone-based material"), a moisture-curing modified silicone-based sealant (hereinafter abbreviated as "modified silicone-based material"), and a moisture-curing urethane-based sealant (hereinafter abbreviated as "urethane-based material").

<Test Results>
Table 1 shows an overview of the results of the content storage test carried out under the above conditions. In Table 1, "○" indicates that no change in the state of the content was observed, "△" indicates that an increase in the viscosity of the content was observed, and "×" indicates that hardening of the content was observed. In other words, "△" and "×" indicate that a change occurred in the state of the content.

As shown in Table 1, when a membrane with an extension length of 0 mm, i.e., a membrane without an extension, was used, thickening was observed near the corners when the contents were modified silicone-based materials, and hardening was observed near the corners when the contents were urethane-based materials. On the other hand, when the extension length was 3 mm or more, no change in state was observed for any of the contents. From the above results, it was confirmed that providing an extension to the membrane as in this embodiment improves the barrier properties of the container and effectively suppresses changes in the state of the contents.

2. Manufacturing Method of the Cartridge-Type Container Next, a manufacturing method of the cartridge-type container CT will be described with reference to FIGS.

After the container body 1 is formed in advance by integral molding of resin, the process of inserting the membrane 2 into the container body 1 is carried out. Figure 4 shows a schematic of this process. The membrane 2 is set at the front end of the insertion jig X, and is sent into the container body 1 by inserting the insertion jig X into the container body 1 from the rear. The outer diameter of the membrane 2 set in the insertion jig X is approximately the same as or slightly smaller than the inner diameter of the body 11, and the membrane 2 is inserted while lightly rubbing against the inner wall of the body 11. Note that the insertion jig X and the membrane 2 do not need to be heated and are inserted at room temperature, so the inner wall of the container body 1 is not damaged by heat during the insertion.

Figure 5 is a diagram of the container body 1 as viewed from the rear. As shown in Figures 4 and 5, the rear surface of the disk-shaped portion 12a has three ring-shaped protrusions 12a1 that surround the opening OP. All of these protrusions 12a1 are slight protrusions with a height of 1 mm or less, and each has the same height.

After the membrane 2 is inserted deep inside the container body 1, as shown in FIG. 6, the membrane 2 is pressed against the disk-shaped portion 12a by the insertion jig X. At this time, the front surface of the membrane 2 (canopy-corresponding portion 21) covers the entire rear surface of the disk-shaped portion 12a, and hits each of the protruding portions 12a1 in particular. The side surface of the membrane 2 (extension portion 22) covers the vicinity of the front end of the body portion 11. There is almost no gap between the canopy-corresponding portion 21 and the disk-shaped portion 12a, and between the extension portion 22 and the body portion 11.

In addition, when the membrane 2 is pressed against the disk-shaped portion 12a by the insertion jig X, high-frequency induction heating (a form of electromagnetic induction heating) is performed by passing an electric current through the aluminum foil (a form of conductive layer) of the membrane 2, as shown in FIG. 7. This high-frequency induction heating can be performed using a high-frequency power source arranged outside the container body 1. In addition, since the aluminum foil of the membrane 2 is directly heated by itself without contacting a heat source, the entire membrane 2 can be heated uniformly and efficiently, and deformation or deterioration of the container body 1 due to heat can be suppressed as much as possible. Note that electromagnetic induction heating using a method other than high frequency may be performed as long as the membrane 2 can be appropriately heated. The electromagnetic induction heating method is excellent in terms of high-speed heating, easy temperature control, and clean handling.

When the aluminum foil of the membrane 2 is heated in this manner, the heat is transferred to the polyethylene layer on the surface of the membrane 2 and to the inner wall of the container body 1, fusing the two together. At this time, the front surface of the membrane 2 (canopy-corresponding portion 21) is in strong contact with each of the protruding portions 12a1, so that fusing is achieved particularly reliably and sufficiently in this portion.

In addition, since each protrusion 12a1 is formed in a ring shape surrounding the opening OP, if at least these parts are sufficiently fused to the canopy corresponding part 21, the container body 1 can be reliably sealed. Furthermore, as the fusion of the canopy corresponding part 21 and each protrusion 12a1 part progresses, the distance between the canopy corresponding part 21 and the disk-shaped part 12a decreases, and the canopy corresponding part 21 is fused to the entire disk-shaped part 12a.

The number and shape of the protrusions provided on the rear surface of the disc-shaped portion 12a are not limited to the above-mentioned form. For example, the protrusions may be in a form in which the entire rear surface of the disc-shaped portion 12a is provided with embossing or unevenness. It is also possible to have no protrusions on the rear surface of the disc-shaped portion 12a.

In addition, in the state shown in FIG. 7, there is almost no gap between the side surface (extension portion 22) of the membrane 2 and the body portion 11, so that both are also fused. For example, the front end of the insertion jig X may be configured to be expandable in the radial direction, so that the extension portion 22 can be pressed radially outward. In this way, the extension portion 22 can be pressed in this manner in the state shown in FIG. 7, and the extension portion 22 and the body portion 11 can be fused more reliably and sufficiently. After the membrane 2 is fused to the container body 1, the insertion jig X is removed, and the plunger 3, barrier film 4, etc. are attached to the container body 1 to complete the cartridge-type container CT.

As a method for attaching the membrane to the container body, the above-mentioned high-frequency induction heating fusion method is preferred in terms of productivity and quality, but other methods can also be used. An example of another method is described below.

One example of this technique is to heat the membrane 2 by irradiating it with a laser, and fuse the membrane 2 to the container body 1. Compared to high-frequency induction heating, this technique requires a relatively large amount of time and effort to heat the entire membrane 2 evenly, and there is a possibility that some areas may be insufficiently heated, but it is possible to fix the membrane 2 to the container body 1.

Another example is a method of attaching the membrane 2 to the container body 1 by applying ultrasonic waves to generate vibrations. This method may generate some debris, but it is possible to attach the membrane 2 to the container body 1.

Yet another example is a method in which a heated hot plate is inserted into the container body 1 and the heat is used to fuse the membrane 2 to the container body 1. However, when using this method, it is desirable to prevent the hot plate from directly contacting the side wall of the body 11 when it is inserted into the container body 1. For example, it is desirable to make the hot plate sufficiently smaller than the inner diameter of the body 11 so that it can be inserted without contacting the side wall, and to make the hot plate an expandable split type so that the extension 22 can be pressed against the body 11 after insertion. As a method for fusing the membrane 2 to the container body 1, in addition to a method of realizing the fusing by heating the membrane 2 in a state where the membrane 2 is in contact with the container body 1, a method of realizing the fusing by pressing the preheated membrane 2 against the container body 1 (for example, a method of pressing the membrane 2 placed at the tip of a hot plate against the container body 1 together with the hot plate, or a method of preheating the remaining part of the membrane 2 and pressing it against the container body 1 when a part of the membrane 2 is insert molded as described later) can also be used. In addition, the membrane 2 may be heated in a non-contact state between the hot plate and the membrane 2 by bringing a hot plate close to the membrane 2 in contact with the container body 1 and utilizing the radiant heat of the hot plate.

In addition, when insert molding the membrane, due to the structure of the mold used for the molding, it is difficult to attach a cup-shaped membrane like that of this embodiment to the container body 1 in one go. Therefore, it is possible to form the container body 1 by insert molding the part (ring-shaped part) corresponding to the extension part 22 of the membrane, and then attach the part (flat part) corresponding to the canopy part 21 of the membrane to the container body 1 using a hot plate or the like, and this method can be used to obtain a product similar to this embodiment. In addition, considering that it is difficult to insert mold the part corresponding to the opening OP in the membrane 2 (conveniently referred to as the "opening corresponding part") due to the structure of the mold used for injection molding of the container body 1, it is also possible to form the container body 1 by insert molding the part of the membrane other than the opening corresponding part (i.e., the part consisting of the outer periphery of the canopy corresponding part 21 and the extension part 22), and then attach the opening corresponding part to the container body 1 using a hot plate or the like.

Although the embodiment of the present invention has been described above, the configuration of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the invention. In other words, the above embodiment should be considered to be illustrative in all respects and not restrictive. The technical scope of the present invention is indicated by the claims, not the description of the above embodiment, and should be understood to include all modifications that are equivalent in meaning and scope to the claims.

The present invention can be used, for example, in containers for storing caulking materials and adhesives.

REFERENCE SIGNS LIST 1 container body 11 body portion 12 lid portion 12a nozzle portion 12b convex portion 13 corner portion 2 membrane 21 lid corresponding portion 22 extension portion 3 plunger 4 barrier film CT cartridge type container X insertion jig

Claims (4)

A container is an integrally molded resin product, and is composed of a container body having a lid portion with an opening at the center provided on the front side of a cylindrical body portion, and a barrier film provided on the outer surface of the body portion,
a barrier member is provided on an inner wall of a canopy of the container body so as to close the opening, the barrier member having a canopy corresponding portion covering the inner wall of the canopy and an extension portion extending rearward from an outer periphery of the canopy corresponding portion;
the extension portion comprises a portion that is fixed to the R-portion wall surface of the inner wall of the corner portion extending from the inner wall of the canopy portion to the inner wall of the body portion so as to cover the entire R-portion along the R-portion wall surface of the inner wall of the corner portion extending from the inner wall of the canopy portion to the inner wall of the body portion, and a portion that is fixed to the vicinity of the front end portion of the inner wall of the body portion continuing from the R-portion of the inner wall, The container according to claim 1, characterized in that the inner wall of the canopy has one or more ring-shaped protrusions surrounding the opening. 3. The container according to claim 1 or 2,
A container characterized in that a plunger is provided to close the rear side of a body portion of the container body, and the plunger is movable within the body portion. A method for manufacturing a container according to any one of claims 1 to 3, comprising the steps of:
A manufacturing method characterized by inserting an insertion jig with the barrier material set at its tip into the inside of the container body from the rear, pressing the canopy corresponding part against the inner wall of the canopy part and pressing the extension part radially outward, and then heating the canopy corresponding part and the extension part to adhere to the container body .