JP4320830B2 - Paper tray - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper tray in which a thermoplastic sheet is adhered to the inner surface of a paper box, and particularly has an internal pressure absorbing function in which a thermoplastic sheet is adhered using a paper box having openings on the side and bottom surfaces. It has a paper tray.
[0002]
[Prior art]
A container formed by laminating a plastic film or a plastic sheet on one side of a paperboard to form a box is widely used. When a container such as a disposable tissue or a fragrance that generates gas over time is accommodated in this container, there arises a problem that the container expands and deforms due to the generated gas so that it does not look good.
[0003]
[Problems to be solved by the invention]
The present invention has been made by paying attention to the above-mentioned problems relating to the paper tray that contains the contents that generate gas over time, such as wet tissue and fragrances. An object of the present invention is to provide a paper tray that absorbs generated gas in a container and does not cause deformation of the container.
[0004]
[Means for Solving the Problems]
A first invention of the present invention is a paper tray in which a thermoplastic sheet is laminated on the inner surface of a flanged paper box, and an opening hole is provided on one surface of the paper box, and the thermoplastic located in the opening hole. The plastic sheet has an internal pressure absorbing part that is recessed inward .
The paper tray is characterized in that the opening hole is provided with a door-like lid that is continuous with one surface of the paper box and is in close contact with the outer surface of the internal pressure absorbing portion .
[0005]
The paper tray according to the second invention is characterized in that, in the first invention, the opening provided in the paper box and the internal pressure absorbing portion provided in the thermoplastic sheet are provided on a side surface of the container. It is.
[0006]
As described above, according to the present invention, an opening hole is provided on one surface of a paper box, and an internal pressure absorbing portion recessed inward is formed in the thermoplastic sheet located in the opening hole. The gas generated from the contents can be absorbed by the swelling of the portion. Further, since the provided outer surface and coherent door-type closure of succession on one side of the carton to open the hole the internal pressure absorbing portion, the thermoplastic sheet of the opening hole is protected by a lid. Further, it is effective that the opening hole provided in the paper box and the internal pressure absorbing portion provided in the thermoplastic sheet are provided on the side surface of the container.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to Examples and Reference Examples . FIG. 1 is a developed explanatory view showing one reference example of the blank 10 used in the present invention, and FIG. 2 is a cross-sectional explanatory view showing one reference example of the paper tray of the present invention.
[0008]
The blank 10 includes a bottom surface 11, a side surface 12, an overlapping piece 13 connected to the side surface 12, and an upper edge piece 14 connected to the upper edge of the side surface, and an opening 15 is provided in a part of the bottom surface or side surface. Yes. The opening hole 15 may be provided not only at one location on the bottom surface or part of the side surface, but also at a plurality of locations, or may be provided across the bottom surface and the side surface. And each part is comprised by punching out paperboard, this is bend-assembled along the fold line m, and it is set as the paper box 10a. The overlapping pieces 13 may be glued to adjacent side surfaces, but may be simply folded and assembled without gluing. As the paperboard, coated balls, coated manila, etc. can be preferably used.
[0009]
The present invention is continuous with one side of the opening hole 15 via the folding line, is provided with a door-shaped lid 16 sized such as to close the opening hole (see FIGS. 3 and 4). The shape of the blank may not be a shape in which adjacent side surfaces are completely separated as in the present reference example, but may be a shape in which adjacent side surfaces are continuous via the folding and joining plate 121 and the second folding and joining plate 141. (See FIG. 5).
[0010]
The thermoplastic sheet 20 can be deep-drawn by a vacuum forming method, a pressure forming method, or the like, and the flange 21 needs to have a certain degree of rigidity. Therefore, polyethylene, polystyrene, polyester having a thickness of about 200 to 400 μm, Polypropylene or the like can be preferably used. From a roll-like sheet such as polyethylene, polystyrene, polyester, polypropylene, etc., first, it adheres to the inner surface of the paper box 10a having an upper edge piece 14 at the peripheral edge with an area slightly larger than the upper surface of the paper box by a known molding method such as vacuum molding The thermoplastic sheet 20 is formed by forming the sheet to be formed by a known forming method such as a vacuum forming method and then punching the outside of the upper edge piece 14. These molding and punching operations are performed continuously.
[0011]
The molding die is provided with a convex portion at a portion corresponding to the opening hole of the paper box, and when the thermoplastic sheet 20 is molded, the internal pressure absorbing portion 22 protruding inward can be molded. (See FIG. 2). The internal pressure absorbing unit 22 is designed to absorb the amount of gas generated by the contents stored in the paper tray.
[0012]
The paper tray is made as follows. That is, the paper box 10a in which the blank 10 is assembled is placed in a molding die. The thermoplastic sheet 20 is placed on the assembled paper box 10a so that the inside of the flange 21 overlaps the upper edge piece 14 of the paper box. Next, the upper edge piece 14 of the paper box and the inner side of the flange 21 of the thermoplastic sheet are bonded by a method such as heat sealing using a seal bar (pre-seal), and at the same time, the thermoplastic sheet 20 is heated and softened with a heater or the like. (Preheat up). Thermal bonding conditions, hot air temperature, and the like are appropriately changed depending on the material, thickness, and the like of the thermoplastic sheet used.
[0013]
Thereafter, when air in the mold is sucked through a suction tube and a suction hole from a vacuum source such as a vacuum pump, the air in the mold is sucked through a gap between the side surface 12 of the paper box 10a and the overlapping piece 13, and the like. Since the inside is in a vacuum state, the heat-softened thermoplastic sheet is bent by pressure and is tightly formed on the inner surface of the paper box, and is formed integrally with the paper box and is formed in the opening hole 15 as shown in FIG. A paper tray having the protruding internal pressure absorbing portion 22 is obtained (vacuum forming method).
[0014]
Note that the close contact molding of the paper box 10a and the thermoplastic plastic sheet 20 may be performed by a pressure forming method in addition to the vacuum forming method, or a forming method using both the vacuum forming method and the pressure forming method.
[0015]
Finally, the formed paper box is removed from the mold and trimmed around it to make a paper tray. The thickness of the flange 21 of the thermoplastic sheet of the finished paper tray is 200 to 40 μm, and the thickness of the portion (housing portion) in close contact with the bottom surface 11 and the side surface 12 of the paper box is 10 to 100 μm. For this reason, since the flange has sufficient rigidity, the paper tray can be provided with a stable shape retaining property, and in the storage portion, only the minimum plastic amount necessary for the barrier property can be obtained.
[0016]
When a suitable amount of wet tissue is accommodated in the produced paper tray and covered with a lid material, gas is generated when time passes in a sealed state. The plastic sheet unit part (the part corresponding to the opening hole of the paper box) is first affected by the internal pressure due to the generation of gas rather than the paper / plastic sheet laminated part, and this part first swells (absorbs the internal pressure forming the recess) By making the portion flat), it becomes possible to suppress deformation (swelling) of the entire paper tray (see FIGS. 3C and 4C).
[0017]
Various variations of the opening hole are possible as shown in FIGS. Further, if the thermoplastic sheet is also transparent, it is possible to recognize the contents from the outside of the tray, and if it is colored, it is possible not to show the contents.
[0018]
[Reference example ]
The reference examples of the present invention will be described more specifically below.
< Reference Example 1>
A coated manila having a basis weight of 210 g / m ² is punched out to produce a paper box 10a from the blank 10 shown in FIG. That is, the blank 10 includes a bottom surface 11, a side surface 12, an overlapping piece 13 connected to the side surface, and an upper edge piece 14 connected to the upper edge of each side surface, and an opening hole 15 is provided in a part of the side surface 12. Each part is formed by punching the coat ball, and this is assembled along the folding line m to assemble the paper box 10a.
[0019]
Separately, a 150 μm thick polypropylene sheet having an area slightly larger than the upper surface of the paper box 10 a and closely attached to the inner surface of the paper box having the flange 21 on the periphery is formed by a known molding method such as an extrusion method, and then the outer side of the flange 21. Is made into a thermoplastic sheet 20.
[0020]
The assembled paper box 10a is placed in a molding die, and a polypropylene sheet as the thermoplastic sheet 20 is placed thereon.
[0021]
The upper edge piece 14 of the paper box and the inside of the flange 21 of the thermoplastic sheet are thermally bonded using a seal bar (pre-seal), and at the same time, the thermoplastic sheet is heated from above with a heater or the like. Soften (preheat up).
[0022]
Thereafter, when the air in the mold is sucked through the suction pipe and the suction hole using a vacuum pump, the air in the mold is sucked through the gap between the side surface 12 of the paper box 10a and the overlapping piece 13, and the inside of the mold is vacuumed. Since the heat-softened thermoplastic sheet is bent by pressure, it is tightly formed on the inner surface of the paper box, and the internal pressure protruding inward into the opening hole 15 as shown in FIG. 2 formed integrally with the paper box. A paper tray having the absorbing portion 22 is formed.
[0023]
Finally, the formed paper box is extracted from the mold and the periphery thereof is trimmed to complete the paper tray of Reference Example 1.
[0024]
【The invention's effect】
As described above, according to the present invention, gas or the like is generated in a rigid container such as a composite container composed of paper and plastic sheet or paper and plastic film, and internal pressure is applied, for example, like a wet tissue. New products can be stored.
[Brief description of the drawings]
FIG. 1 is a developed explanatory view showing a reference example of a blank used in the present invention.
FIG. 2 is a cross-sectional explanatory view showing a reference example of the paper tray of the present invention.
FIGS. 3A and 3B show an embodiment of the paper tray of the present invention, FIG. 3A is a cross-sectional explanatory view, FIG. 3B is a perspective explanatory view, and FIG. 3C is a main part perspective view showing a state in which internal pressure is absorbed; It is explanatory drawing.
4A and 4B show another embodiment of the paper tray of the present invention. FIG. 4A is a cross-sectional explanatory view, FIG. 4B is a perspective explanatory view, and FIG. 4C is a main part showing a state in which internal pressure is absorbed. FIG.
FIG. 5 is a development explanatory view showing another reference example of a blank used in the present invention.
FIGS. 6A and 6B show another reference example of the opening hole of the paper tray of the present invention, FIG. 6A is a cross-sectional explanatory view, and FIG. 6B is a perspective explanatory view.
7A and 7B show another reference example of the opening hole of the paper tray of the present invention, FIG. 7A is a cross-sectional explanatory view, and FIG. 7B is a perspective explanatory view.
8A and 8B show another reference example of the opening hole of the paper tray of the present invention, FIG. 8A is a cross-sectional explanatory view, and FIG. 8B is a perspective explanatory view.
[Explanation of symbols]
10. Blank 10a ... Paper box 11 ... Bottom 12 ... Side 13 ... Overlapping piece 14 ... Upper edge piece 15 ... Opening hole 16 ... Lid 20 ... Thermoplastic sheet 21 ... Flange 22 ... Internal pressure Absorbing part 121 ... Folding joining plate 141 ... Second folding joining plate m ... Folding line

Claims (2)

A paper tray in which a thermoplastic sheet is laminated on the inner surface of a flanged paper box. An opening hole is provided on one surface of the paper box, and the thermoplastic sheet located in the opening hole is recessed inwardly. The internal pressure absorption part is formed ,
The paper tray, wherein the opening hole is provided with a door-like lid that is continuous with one surface of the paper box and is in close contact with the outer surface of the internal pressure absorbing portion . Pressure absorbing portion provided in the opening hole and a thermoplastic sheet provided in the paper box, according to claim 1 Symbol mounting paper tray, characterized in that provided on the side of the container.

Images