JP3868039B2 - Composite container and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a composite container that can be suitably used for secondary packaging of foods in which moisture evaporates with cooling after primary packaging in a heated state, such as cheese, and a method for manufacturing the same.
[0002]
[Prior art]
As a composite container, for example, a container made of a frame material made of resin and a paper blank having a resin layer on the surface, and a frame material and a resin layer of the paper blank are bonded to each other and the frame material and the paper blank are joined together. Are known.
[0003]
On the other hand, as a composite container using paper and a resin molded product, for example, a paper blank is inserted into an injection mold and a so-called pillared container formed by integrally molding a resin and a paper blank, and further resin injection. There is known a lid formed by molding a frame material by molding and joining the frame material and a paper blank having a resin layer on the joining surface.
[0004]
[Problems to be solved by the invention]
However, since both the container and the lid described above have a resin layer on the joint surface of the paper blank with the frame material, there is a drawback that the air permeability and moisture permeability are poor.
[0005]
Therefore, it is necessary to store the product in a heated state as it is, and further improvement of air permeability and moisture permeability is desired as a container for food such as cheese in which moisture evaporates after storage.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the composite container of the present invention is a composite container composed of a frame material obtained by injection molding a resin , and a paper blank having moisture permeability and air permeability. The joint surface with the frame material is made of a paper layer, and an energy director is provided at a joint portion of the frame material with the paper blank, and the frame material and the paper blank are joined by ultrasonic welding. Furthermore, the paper blank is composed of only paper.
[0007]
The method for manufacturing a composite container according to the present invention includes a step of preparing a frame material obtained by injection molding a resin and provided with an energy director at a bonding portion with a paper blank, and a bonding surface with the frame material. RiToru wet such a paper layer, a step of preparing a paper blank that have a breathability, and the paper blank and the frame member is configured comprising the step of ultrasonic welding, if necessary, as the paper blank A configuration using only paper is used, and further, a step of bringing the paper blank into a wet state before the step of ultrasonically welding the frame material and the paper blank is adopted.
[0008]
The composite container of the present invention consists of a frame material obtained by injection molding a resin , and a paper blank having moisture permeability and air permeability, and the joint surface with the frame material in the paper blank is composed of a paper layer, An energy director is provided at a joint portion of the frame material with the paper blank, and the frame material and the paper blank are joined by ultrasonic welding. In this bonding, the resin forming the frame material, particularly the energy director, is melted by ultrasonic vibration and bites into the paper layer of the paper blank, so that sufficient bonding strength is realized. Therefore, in the composite container of the present invention, the resin layer can be easily removed from the paper blank, and the air permeability and moisture permeability are improved.
[0009]
On the other hand, the method for manufacturing a composite container of the present invention includes a step of preparing a frame material obtained by injection molding a resin and provided with an energy director at a bonding portion with a paper blank, and a bonding surface with the frame material. RiToru moisture such from the paper layer is composed of a step of preparing a paper blank that have a breathability, and the paper blank with the frame member and the step of ultrasonic welding.
[0010]
In this method, since a frame material obtained by injection molding of a resin and a paper blank made of a paper layer are joined to the frame material, the frame material is joined by ultrasonic welding. It is not necessary to use a paper blank having a resin layer on the joint surface with the material.
[0011]
Therefore, according to this method consists only paper layer, moisture permeability without containing resin layer, since using paper blank that have a breathable, high bonding strength between the paper blank and the frame member Moreover, it is possible to efficiently produce a composite container excellent in air permeability and moisture permeability. Also, in this method, a composite container that is unlikely to warp can be easily obtained by placing the paper blank in a wet state before joining to the frame material.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the composite container of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the composite container includes a frame material 1 made of resin and a paper blank 2 joined to the frame material 1.
[0013]
The frame material 1 is obtained, for example, by injection molding of a resin. As a resin as a molding material, polystyrene [general use (GP grade), impact resistant (HI grade), etc.], ABS resin, AS resin, etc. And polystyrene resins such as polypropylene, and polyolefin resins such as polypropylene and polyethylene. Among these, polystyrene is preferable in terms of suitability for ultrasonic welding.
[0014]
As shown in FIGS. 3 and 4, an energy director 10 is provided at a joint portion of the frame member 1 with the paper blank 2. The energy director 10 has an action or function of biting into the paper layer of the paper blank 2 while being melted by vibration caused by ultrasonic waves during ultrasonic welding. Therefore, in this composite container, the bonding strength between the frame material 1 and the paper blank 2 can be made sufficiently high by using the paper blank 2 whose bonding surface with the frame material 1 is a paper layer.
[0015]
As shown in FIGS. 2 and 3, the frame member 1 can be provided with a vent hole 20 as necessary. By providing the vent hole 20, the air permeability of the composite container can be further improved.
[0016]
Moreover, as shown in FIG.1, FIG2 and FIG.4, the leg part 30 can also be protrudingly provided in the bottom face part of the frame material 1 as needed. As shown in FIG. 2, the leg portion 30 may be partially provided on the bottom surface portion of the frame member 1 or may be continuously provided on the entire circumference of the bottom surface portion.
[0017]
As the paper blank 2, one having a paper layer on the joint surface with the frame member 1 can be used. Therefore, when high air permeability and moisture permeability are required for this composite container, a paper blank made of so-called raw paper that does not contain a resin layer can be suitably used.
[0018]
Examples of the paper forming the paper blank 2 include cup base paper, card base paper, and coated cardboard.
The frame material 1 and the paper blank 2 are joined together by melting the energy director 10 using a so-called melting allowance of the energy director 10 provided on the frame material 1 by ultrasonic welding.
[0019]
The shape of the composite container can be appropriately determined according to the use and purpose, and may be any shape such as a circle, a semicircle, an ellipse, a triangle, a polygon such as a rectangle, and the like.
[0020]
This composite container is usually combined with a lid selected from various lids such as a lid made of paper, a lid made of a laminate of paper and resin, a lid made of resin, etc. Have been used. Moreover, you may combine with the cover body of the same structure as this composite container. That is, the structure of the composite container can be applied to the structure of the lid.
[0021]
Next, the manufacturing method of the composite container of this invention is demonstrated.
In the method of the present invention, first, a frame material 1 made of a resin and provided with an energy director 10 at a joint portion with the paper blank 2 and a paper blank 2 made of a paper layer as a joint surface with the frame material 1 are prepared. To do.
[0022]
The frame material 1 made of resin and provided with the energy director 10 at the joint with the paper blank 2 is formed by suitably adopting, for example, an injection molding method.
As the paper blank 2, a paper blank having a joint portion with the frame material 1 is used, and a paper blank that does not contain a resin layer can be suitably used.
[0023]
Next, the paper blank 2 is placed at a predetermined position of the frame member 1, and the frame member 1 and the paper blank 2 are joined using an ultrasonic vibration method.
In addition, when the contents stored in this composite container evaporate water after storage to generate steam, and the paper blank 2 is made only of paper, the contents are stored in this composite container. After the storage, the paper blank 2 may absorb water that evaporates from the contents and warp the paper blank 2 in some cases.
[0024]
In order to prevent the occurrence of the warp, a step of previously bringing the paper blank 2 into a wet state may be provided at a stage before the frame material 1 and the paper blank 2 are joined.
How much the paper blank 2 should be moistened depends on the size, shape, content type, moisture content, etc. of the paper blank 2 and is difficult to determine uniformly. When the content is cheese individually wrapped with aluminum foil and the shape of the paper blank 2 is a semicircle with a radius of about 52 mm, the paper blank 2 made of so-called raw paper is heated at a temperature of 40 ° C. and a humidity of 90 % To a temperature of 60 ° C., humidity of 98%, etc., and left for about 24 hours, it can be in a wet state where warpage is unlikely to occur. As an example of a wet state, it is preferable to adjust raw paper having a water content of 5 to 7% so that the water content is about 9 to 11%.
[0025]
The composite container manufactured by this method has a sufficiently high bonding strength between the frame member 1 and the paper blank 2, and is excellent in air permeability and moisture permeability.
Moreover, this manufacturing method of a composite container is applicable also to the manufacturing method of a cover body.
[0026]
【The invention's effect】
Composite container of the present invention, RiToru wet bonding surface, such a paper layer between the frame member and the frame member energy director is provided at the junction of the paper blank with the resulting resin by injection molding, breathable since the paper blank with ultrasonic welding that have a, equipped with sufficient strength, is excellent in air permeability, moisture permeability.
[0027]
Therefore, this composite container can be suitably used as a packaging container for foods such as cheese and other contents whose moisture evaporates after storage.
Further, the method of producing the composite container of the present invention, the junction surface of the frame member the energy director is provided at the junction of the paper blank with the resulting resin by injection molding and the frame member is Ri Do from the paper layer breathable, prepared paper blank that have a breathability. Thus the production of composite container by the those of the frame member and the paper blank ultrasonic welding, provided a sufficient strength, air permeability and moisture A composite container having excellent wettability can be obtained efficiently.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of a composite container of the present invention.
FIG. 2 is a bottom view showing an example of the composite container of the present invention.
FIG. 3 is a plan view showing an example of a frame material constituting the composite container of the present invention.
FIG. 4 is a cross-sectional view showing an example of a frame material constituting the composite container of the present invention.
[Explanation of symbols]
1 ... Frame material 2 ... Paper blank
10 ... Energy director
20… Vent hole
30 ... Leg

Claims (5)

A composite container comprising a frame material obtained by injection molding a resin , and a paper blank having moisture permeability and air permeability , wherein a joint surface of the paper blank with the frame material is a paper layer, and the frame material In the composite container, an energy director is provided at a joint portion with the paper blank, and the frame member and the paper blank are joined by ultrasonic welding.   The composite container according to claim 1, wherein the paper blank is made only of paper. Yes preparing a frame member energy director is provided at the junction of the paper blank with the resulting resin by injection molding, RiToru moisture such joint surface from the paper layer of the frame member, breathable preparing a paper blank you method of producing a composite container characterized by comprising the said paper blank with the frame member and a step of ultrasonic welding.   The manufacturing method of the composite container of Claim 3 using what consists only of paper as said paper blank.   The manufacturing method of the composite container of Claim 3 or Claim 4 which has the process of making the said paper blank wet before the process of ultrasonically welding the said frame material and the said paper blank.

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