JP2014144613A - Pulp molded container with cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulp molded container with a cap, strength of whose hinge part is improved at a low cost.SOLUTION: A container 11 and a cap 12 are set on a metallic mold M in parallel, and between which and a heater disposed over them, a bilayer thermoplastic film f is supplied and heated by the heater H. The heated thermoplastic film f is sucked toward the inside surface of the container 11 by using suction holes arranged on the metallic mold M. By spreading and melt-adhering the thermoplastic film f over the inside surfaces of the container 11 and the cap 12, a water-resistant layer 14 is formed and a pulp molded container 10 with a cap is completed. At the same time with formation of such a water-resistant layer 14, a hinge part 15 is formed on the water-resistant layer 14 at a connection part of the container 11 and the cap 12. Since the hinge part 15 comprises a flexible and easily-bendable thermoplastic film, it is unnecessary to form a perforation for facilitating the folding work as is the case in a pulp molded composition. As a result, a sharp rise of the production cost due to formation of the perforations and strength deterioration of the hinge part can be prevented.

Description

  The present invention relates to a pulp mold container with a lid and a method for producing the same.

  As containers for storing foods and the like, plastic containers obtained by molding a synthetic resin material and paper containers obtained by folding a blank made of paperboard and bonding them together with an adhesive are known. These are widely used because they are lightweight, inexpensive and can be disposable, but plastic containers cannot be discarded as combustible waste, and paper containers have the disadvantage that they are peeled off by the heat of the contents.

Therefore, a pulp mold container is also used in which a pulp material such as straw or sugarcane is used as a raw material and the raw material is molded with a mold. Unlike a plastic container, a pulp mold container can be disposed of as combustible waste, and unlike a paper container, the whole is integrally molded, so that a situation in which the adhesive is peeled off does not occur.
Since such a pulp mold container is inferior in water resistance unlike a plastic container, a container containing a content containing a lot of moisture such as food is thermoplastic on the inner surface of the container as in Patent Document 1. In general, a water-resistant layer is formed by laminating films.

  As a pulp mold container of this type, as in Patent Document 2, a container body and a lid connected to the opening of the container body are integrally molded, and a connecting portion between the container body and the lid is bent to form a hinge portion. There is known a pulp mold container with a lid that allows the lid to rotate between a position at which the opening of the container body is closed and a position at which the opening is opened.

In such a pulp mold container with a lid, the pulp mold material itself lacks flexibility and is difficult to bend. It is common to do.
However, the manufacturing cost of the pulp mold container with a lid is increased by the work for forming the perforation, and the strength of the hinge portion is lowered due to the perforation, and it is easy to break. Furthermore, it is not preferable that paper dust of the pulp material is generated during the formation of perforations.

JP 2012-158160 A JP 2006-206103 A

  Therefore, the problem to be solved by the present invention is to improve the strength of the hinge part at a low cost with respect to the pulp mold container with a lid.

  In order to solve the above-described problems, as a pulp mold container with a lid according to the invention, a container body made of a pulp mold, a lid made of a pulp mold, and spanned from the container body to the lid, the inner surface of the container body A water-resistant layer made of a thermoplastic film welded to the entire surface and the entire inner surface or outer surface of the lid, and a bridging point between the container body and the lid of the water-resistant layer is the center. A configuration is adopted in which the lid is a hinge portion that can be rotated between a position for closing the opening of the container body and a position for opening the opening of the container body.

  Moreover, as a manufacturing method of a pulp mold container with a lid according to the invention, a step of juxtaposing a container body made of a pulp mold and a lid made of a pulp mold, and a thermoplastic film heated over the lid from the container body, And a step of welding to the entire inner surface of the container body and the entire inner surface or outer surface of the lid.

Since the hinge portion is made of a water-resistant layer, and the water-resistant layer is made of a flexible and easily bendable thermoplastic film, it is not necessary to form a perforation in the hinge portion in order to facilitate folding.
Therefore, it is possible to prevent an increase in manufacturing cost and generation of paper dust accompanying the formation of perforations, and it is possible to prevent a decrease in strength of the hinge portion.

The perspective view of the pulp mold container with a lid of an embodiment Sectional drawing of the pulp mold container with a lid of an embodiment Schematic of manufacturing process of pulp mold container with lid of embodiment Sectional drawing of the pulp mold container with a lid of other embodiments

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1 and FIG. 2, the pulp mold container 10 with a lid of the embodiment includes a two-layer structure of an outer container 11 and a lid 12, and a water-resistant layer 14 laminated inside the container 11 and the lid 12. It has become. Although the content is not specifically limited, it is mainly used suitably for storing food such as lunch boxes and gratin.

Although the shape of the container 11 is not particularly limited, in FIGS. 1 and 2, the bottom wall 11 a having an oval shape in plan view, the peripheral wall 11 b rising from the periphery of the bottom wall 11 a, and the upper edge of the peripheral wall 11 b A flange having a flange 11c extending substantially horizontally is shown. An upwardly protruding protrusion 11d is formed on the entire circumference of the flange 11c.
The shape of the lid 12 is not particularly limited as long as the opening of the container 11 can be closed. However, in FIGS. 1 and 2, the top wall 12 a that is oval in plan view and the peripheral wall 12 b that hangs down from the periphery of the top wall 12 a. And a flange 12c projecting substantially horizontally from the lower edge of the peripheral wall 12b. As illustrated, the bottom wall 11a and the peripheral wall 11b of the container 11 and the top wall 12a and the peripheral wall 12b of the lid 12 are similar in shape.

The container 11 and the lid 12 can be obtained by using a pulp material such as straw or sugar cane as a raw material and molding it.
As a production method thereof, a known method can be used. For example, a pulp suspension is prepared, a pulp is made from the pulp suspension in a net form, and the male and female are heated while the finished product is heated. It is possible to exemplify molding a molded product by pressing with a press die.
There are no particular limitations on the type of pulp, the type of binder, the number of mesh meshes, the heating temperature, the pressing pressure, the pressing time, the clearance between male and female pressing dies, and the like.
The wall thickness of the container 11 and the lid 12 is not particularly limited, but if it is too small, the strength cannot be ensured, and if it is too large, the material cost is increased.

  An oval missing portion 13 is formed at the center of the top wall 12 a of the lid 12. Note that the number, position, shape, and size of the missing portion 13 are not particularly limited, and a plurality of missing portions 13 may be provided, may be provided in a circular shape or a polygonal shape, or may be provided at an appropriate location on the peripheral wall 12b of the lid 12 or the container 11. Good. Further, the missing portion 13 can be omitted.

  As shown in FIGS. 1 and 2, the water-resistant layer 14 is formed by heat-welding a multi-layer thermoplastic film having high transparency over the entire surface from the inner surface of the container 11 to the inner surface including the missing portion 13 of the lid 12. Has been. The water-resistant layer 14 prevents the moisture of the food from entering the container 11 and the lid 12 which are inferior in water resistance.

In particular, the missing portion 13 of the lid 12 is also covered and sealed with the water-resistant layer 14, thereby preventing the contents from leaking through the missing portion 13, and conversely, dust or the like from entering from the outside. .
Thus, the missing part 13 covered with the transparent water-resistant layer 14 serves as the window 13 of the pulp mold container 10 with a lid through which the inside can be visually recognized, and the state of contents such as food can be confirmed. It is like that.

Further, the container 11 and the lid 12 are connected by a water-resistant layer 14 spanned between them.
Since the water-resistant layer 14 is made of a thermoplastic film having good flexibility, the lid 12 is centered on the connection portion 15 of the water-resistant layer 14 with the container 11 as shown in FIGS. 1 (a) and 2 (a). It can be rotated between a position where the opening of the container 11 is opened and a position where the opening of the container 11 is closed as shown in FIGS. 1 (b) and 2 (b). As shown in the drawing, in a state in which the opening of the container 11 is closed, the portion inside the protrusion 11d of the flange 11c of the container 11 and the flange 12c of the lid 12 are overlapped.
As a center of such rotation, a connecting portion of the water-resistant layer 14 between the container 11 and the lid 12 is a hinge portion 15.
In addition, in the state which accommodated the contents and the opening of the container 11 was closed, the water-resistant layer 14 on the flange 11c of the container 11 and the water-resistant layer 14 on the flange 12c of the lid 12 were welded, and a pulp mold with a lid was formed. The container 10 can also be sealed. In this case, if both water-resistant layers 14 are formed so as to protrude somewhat from the outer edges of both flanges 11c and 12c, the welded area between the water-resistant layers 14 increases, and the occurrence of poor sealing can be prevented.

Although the kind of thermoplastic film which comprises such a water resistant layer 14 is not specifically limited, A polypropylene (PP) type film, a polyethylene (PE) type film, and a polyethylene terephthalate (PET) type film can be illustrated.
Although the thickness of the water-resistant layer 14 is not specifically limited, 5-200 micrometers can be illustrated. Even if a thermoplastic film is laminated on the pulp mold, it can be treated as combustible waste if it has such a small thickness (classified as a paper container in the Container Recycling Law). Compared to the case where the entire container 11 or the like is made of plastic, the amount of plastic used with a large environmental load can be greatly reduced.

The configuration of the pulp mold container 10 of the embodiment is as described above. Next, the manufacturing method thereof will be described.
First, the container 11 and the lid 12 are respectively molded in advance. In this case, the container 11 and the lid 12 may be molded integrally and then cut and separated by a cutter or the like.
Then, as shown in FIG. 3A, a part of the lid 12 is hollowed out with a cutter or the like to form the missing portion 13.

The lid 12 on which the container 11 and the missing portion 13 are formed is set in the mold M and held in a parallel state as shown in FIG. It is assumed that a number of suction holes (not shown) are formed in the mold M.
Then, a thermoplastic film f is supplied between the mold M and the heater H disposed above the mold M, and is heated by the heater H.

Next, the heated thermoplastic film f is sucked toward the inner surfaces of the container 11 and the lid 12 by evacuating the suction hole of the mold M or the like. Here, since the container 11 and the lid 12 are made of a pulp mold and have air permeability, the suction force of the suction holes is not hindered. If the suction force is insufficient, a large number of fine holes may be formed in the container 11 and the lid to enhance the air permeability.
In addition, the mold M can be divided into a part for holding the container 11 and a part for holding the lid 12, and may be configured to be appropriately combined.

Thus, as shown in FIG. 3C, the thermoplastic film f is deformed into a shape along the inner surfaces of the container 11 and the lid 12 and welded to form the water-resistant layer 14, and the pulp mold container 10 with the lid is completed. To do. The technology for forming such a water-resistant layer 14 is known per se, and the heating temperature of the thermoplastic film f, the magnitude of the suction force of the suction holes of the mold M, the heating and suction time, and the like are within the scope of the known technology. It can be adjusted as appropriate.
Simultaneously with the formation of the water-resistant layer 14, the missing portion 13 of the lid 12 is covered with the water-resistant layer 14, so that the window 13 is formed and the container 11 and the lid 12 are connected with the water-resistant layer 14. Thus, a hinge part is formed. As shown in FIG. 3C, the excess portion of the thermoplastic film f is appropriately cut.
Various types of pulp molded articles as containers with lids can be produced by appropriately combining containers 11 and lids 12 of various shapes and connecting them with hinge portions 15 made of water-resistant layers 14.

FIG. 4 shows a pulp mold container 10 with a lid according to another embodiment.
The pulp mold container 10 with a lid according to this embodiment includes an inner dish 16 in addition to the container 11 and the lid 12.

  Similar to the container 11, the intermediate dish 16 includes a bottom wall 16 a, a peripheral wall 16 b that spreads and rises from the periphery of the bottom wall 16 a, and a flange 16 c that projects substantially horizontally from the upper edge of the peripheral wall 16 b. The bottom wall 16 a and the flange 16 c are substantially similar to the bottom wall 11 a and the flange 11 c of the container 11, but the peripheral wall 16 b is lower than the peripheral wall 11 b of the container 11. As shown in FIG. 4 (b), the intermediate dish 16 has a flange 16 c superimposed on the flange 11 c of the container 11 so that it is supported on the opening of the container 11 and is different from the contents stored in the container 11. Objects (for example, condiments) can be stored.

The water-resistant layer 14 is composed of a multilayer thermoplastic film, and is formed by spanning and welding the thermoplastic film from the inner surface of the lid 12 to the inner surface of the container 11 and from the inner surface of the container 11 to the outer surface of the intermediate dish 16. ing. That is, in this embodiment, the water resistant layer 14 is formed on the outer surface of the inner tray 16.
The container 11 and the inner dish 16 are connected by a water-resistant layer 14, and the connecting portion is a hinge portion 15. For this reason, the inner tray 16 can be rotated between the position where it covers the opening of the container 11 and the position where it is removed from the opening of the container 11 with the hinge portion 15 as the center. The intermediate dish 16 is supported on the opening of the container 11 when the flange 16 c is overlapped with the flange 11 c of the container 11 in a state of being covered with the opening of the container 11.
As can be seen from FIG. 4B, the contents of the inner dish 16 can be visually recognized through the window 13 formed in the lid 12.

  It should be considered that the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications and variations within the scope and meaning equivalent to the terms of the claims.

For example, the water resistant layer 14 may be provided on the outer surface of the lid 12 by bridging and welding a thermoplastic film from the inner surface of the container 11 to the outer surface of the lid 12. Similarly, the water resistant layer 14 may be provided on the inner surface of the inner tray 16.
In the embodiment, the thermoplastic film is a multilayer, but it may be a single layer.

DESCRIPTION OF SYMBOLS 10 Pulp mold container with a lid 11 Container 11a Bottom wall 11b Perimeter wall 11c Flange 11d Projection 12 Lid 12a Top wall 12b Perimeter wall 12c Flange 13 Window (missing part)
14 Water Resistant Layer 15 Hinge Part 16 Middle Pan 16a Bottom Wall 16b Peripheral Wall 16c Flange M Mold H Heater f Thermoplastic Film

Claims (2)

A container body made of a pulp mold;
A lid made of pulp mold;
A water resistant layer made of a thermoplastic film spanned from the container body to the lid, and welded to the entire inner surface of the container body and the entire inner surface or outer surface of the lid;
A bridging point between the container body and the lid of the water-resistant layer rotates around the position between the position at which the opening of the container body is opened and the position at which the opening of the container body is opened. A pulp mold container with a lid that is a possible hinge. A step of arranging a container body made of a pulp mold and a lid made of a pulp mold in parallel with an interval;
A method of manufacturing a pulp mold container with a lid, comprising: spanning a thermoplastic film heated from the container body to the lid, and welding the whole surface of the inner surface of the container body and the entire inner surface or outer surface of the lid.

Images