JP6250287B2 - Pulp mold molding - Google Patents

Description

  The present invention relates to a pulp molded product 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.
Such a pulp mold container and its lid (hereinafter collectively referred to as a pulp mold molded body) are inferior in water resistance unlike a plastic container, and therefore contain contents containing a lot of moisture such as food. In general, as in Patent Document 1, a water-resistant layer is formed by laminating a thermoplastic film on the inner surface.

  By the way, when the water-resistant layer is formed on the inner surface of the pulp mold molded body as described above, normally, as in Patent Document 1, the pulp mold molded body is set in a mold in which a large number of suction holes are formed. Supplying a thermoplastic film between the mold and the heater disposed above, sucking the thermoplastic film heated by the heater toward the inner surface of the pulp mold molded body by the suction force of the suction holes of the mold, It depends on the method of welding.

Such a suction method utilizes the fact that the pulp mold itself has air permeability, but when the water resistant layer is formed on the inner surface of the molded body, the air permeability is lost. Therefore, when it is desired to form a water resistant layer on the outer surface of the molded body in order to further improve the water resistance, the suction method cannot be used.
Although it is possible to use other methods such as manually attaching a film to the outer surface of the pulp mold molded body, it takes time and the manufacturing cost increases.

JP 2012-158160 A

  Therefore, the problem to be solved by the present invention is to reduce the manufacturing cost of a pulp mold molded body in which a water-resistant layer is formed on both the inner surface and the outer surface.

In order to solve the above-described problems, the pulp mold molded body according to the invention includes an inner molded body made of a pulp mold, and a pulp mold that is substantially similar to the inner molded body and is superimposed on the outside of the inner molded body. An outer molded body, and a water-resistant layer made of a thermoplastic film spanned from the inner molded body to the outer molded body and welded to the entire inner surface of the inner molded body and the entire outer surface of the outer molded body, It was set as the structure provided.
When the molded body is a container, the inner molded body and the outer molded body are respectively in the inner container and the outer container. When the molded body is a lid, the inner molded body and the outer molded body are respectively in the inner lid and the outer lid. It becomes.
Here, it is preferable that the water-resistant layer on the inner surface of the inner molded body and the water-resistant layer on the outer surface of the outer molded body are welded.

Moreover, as a method for producing a pulp mold molded body according to the invention, an inner molded body made of a pulp mold and an outer molded body made of a pulp mold that is substantially similar to the inner molded body are arranged in parallel at intervals, and A step of spanning a thermoplastic film from the inner molded body to the outer molded body, and welding the entire inner surface of the inner molded body and the entire outer surface of the outer molded body; And a step of superposing the outer molded body on the outer side with the molded body on the inner side.
Here, it is preferable that the method further includes a step of welding the water-resistant layer on the inner surface of the inner molded body and the water-resistant layer on the outer surface of the outer molded body, which are overlapped.

  According to the present invention, the thermoplastic film is sucked and welded to the inner surface of the inner molded body and the outer surface of the outer molded body, respectively, and the inner molded body is overlapped with the outer molded body on the inner side, thereby providing water resistance on both sides. Since the pulp mold molded body in which the layer is formed can be produced only by the suction method, it is not necessary to manually attach the film to the outer surface or the inner surface of the molded body, and the manufacturing cost can be reduced.

  Further, when the water-resistant layer on the inner molded body side and the water-resistant layer on the outer molded body side are welded in a state where both molded bodies are overlapped, the inner molded body and the outer molded body are prevented from being decomposed.

The perspective view of the pulp mold container of an embodiment Sectional drawing of pulp mold container of embodiment Schematic of manufacturing process of pulp mold container of embodiment

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2, the pulp mold container 10 of the embodiment includes an inner container 11 and an outer container 12, and a water resistant layer 15 laminated on the inner surface of the inner container 11 and the outer surface of the outer container 12. Although the content is not specifically limited, it is mainly used suitably for storing food such as lunch boxes and gratin.

  The shape of the inner container 11 and the outer container 12 is not particularly limited as long as the inner container 11 is overlapped with the inner side of the outer container 12 and is located below. However, in FIGS. 12 is a similar shape. The bottom walls 11a and 12a each having a circular shape in plan view, the peripheral walls 11b and 12b rising from the peripheral edges of the bottom walls 11a and 12a, and the flanges 11c and 12c protruding substantially horizontally from the upper edges of the peripheral walls 11b and 12b, have.

The inner container 11 and the outer container 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 inner container 11 and the outer container 12 is not particularly limited, but if it is too small, the strength cannot be ensured, and if it is too large, it is preferably 0.2 mm to 2.0 mm because the material cost increases. .

  At the same position of the central part of the bottom walls 11a and 12a of the inner container 11 and the outer container 12, respectively, similar and circular missing parts 13 and 14 are formed. Note that the number, position, shape, and size of the missing portions 13 and 14 are not particularly limited as long as the positions of the missing portions 13 and 14 are matched, and a plurality of missing portions 13 and 14 are provided. You may provide in the surrounding walls 11b and 12b. Also, the missing portions 13 and 14 can be omitted.

  As shown in FIGS. 1 and 2, the water-resistant layer 15 is formed by applying a highly transparent multilayer thermoplastic film from the inner surface including the missing portion 13 of the inner container 11 to the outer surface including the missing portion 14 of the outer container 12. It is formed by heat welding on the entire surface. The water resistant layer 15 prevents the moisture of the food from entering the inner container 11 and the outer container 12 which are inferior in water resistance.

In particular, the missing parts 13 and 14 of the inner container 11 and the outer container 12 are also covered and sealed with the water-resistant layer 15, so that the contents leak through the missing parts 13 and 14, and dust or the like enters from the outside. Is prevented.
In this way, the missing portions 13 and 14 covered with the transparent water-resistant layer 15 are the windows 13 and 14 of the pulp mold container 10 through which the inside can be visually confirmed, and the state of the contents such as food can be changed. It can be confirmed.

Further, the inner container 11 and the outer container 12 are connected by a water-resistant layer 15 spanned between them.
Since the water-resistant layer 15 is made of a thermoplastic film having good flexibility, the outer container 12 is centered on the connection portion 16 of the water-resistant layer 15 with the inner container 11 as shown in FIGS. 1B and 2B. It is possible to rotate between the superimposed position and the disassembled position as shown in FIGS. 1 (a) and 2 (a).
As a center of such rotation, a connecting portion between the inner container 11 and the outer container 12 of the water-resistant layer 15 is a hinge portion 16.
In the state where the inner container 11 and the outer container 12 are overlapped, the water-resistant layer 15 on the flange 11c of the inner container 11 and the water-resistant layer 15 on the flange 12c of the outer container 12 are welded, The outer container 12 can be coupled so as not to separate. In this case, if the water-resistant layers 15 are formed so as to protrude somewhat from the outer edges of the flanges 11c and 12c, the welded areas of the water-resistant layers 15 are increased, and the occurrence of poor bonding can be prevented.
Moreover, the inner container 11 and the outer container 12 can also be combined separately using an adhesive or the like.

Although the kind of thermoplastic film which comprises such a water resistant layer 15 is not specifically limited, A polypropylene (PP) type film, a polyethylene (PE) type film, and a polyethylene terephthalate (PET) type film can be illustrated.
The thickness of the water-resistant layer 15 is not particularly limited, but may be 5 to 200 μm. 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 inner container 11 and the like are 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 inner container 11 and the outer container 12 are respectively molded in advance. In this case, the inner container 11 and the outer container 12 may be formed integrally and cut and separated by a cutter or the like.
Then, as shown in FIG. 3A, a part of each of the inner container 11 and the outer container 12 is hollowed out with a cutter or the like to form the missing portions 13 and 14.

The inner container 11 and the outer container 12 in which the missing portions 13 and 14 are formed in this way are set in the mold M as shown in FIG. 3B, and are held upside down and in parallel. 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 surface of the inner container 11 and the outer surface of the outer container 12 by evacuating the suction hole of the mold M or the like. Here, since the inner container 11 and the outer container 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 inner container 11 and the outer container 12 to enhance the air permeability.

Thus, as shown in FIG. 3 (c), the thermoplastic film f is deformed into a shape along the inner surface of the inner container 11 and the outer surface of the outer container 12, and welded to form the water resistant layer 15, and the pulp mold container 10 Is completed. Such a technique for forming the water-resistant layer 15 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 time of heating and suction, and the like are within the scope of known techniques. It can be adjusted as appropriate.
Simultaneously with the formation of the water-resistant layer 15, the missing portions 13 and 14 of the inner container 11 and the outer container 12 are respectively covered with the water-resistant layer 15, so that windows 13 and 14 are formed, and the inner container 11 and the outer container 12 are formed. As a result, the hinge portion 16 is formed.
Furthermore, a process of superposing these inner containers 11 on the inner side and outer containers 12 on the outer side and welding the water-resistant layers 15 to each other by heating may be added.

  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, in the embodiment, the pulp mold container 10 is composed of the inner container 11 and the outer container 12, but the pulp mold lid may be composed of an inner lid and an outer lid. Moreover, it is good also as a pulp mold container with a lid. In that case, a container is comprised from the inner container 11 and the outer container 12, and a lid | cover is comprised from an inner lid and an outer lid, and a container and a lid are a water-resistant layer on both surfaces. Can be formed. In the case of a pulp mold container with a lid, the container and the lid can be connected by, for example, spanning and welding the thermoplastic film f from the inner container 11 to the inner surface or the outer surface of the lid. The connecting portion serves as a hinge portion, and the lid can be rotated between a position where the opening of the container is closed and a position where the opening of the container is opened.
In the embodiment, the thermoplastic film is a multilayer, but it may be a single layer.

DESCRIPTION OF SYMBOLS 10 Pulp mold container 11 Inner container 11a Bottom wall 11b Perimeter wall 11c Flange 12 Outer container 12a Bottom wall 12b Perimeter wall 12c Flange 13, 14 Window (missing part)
15 Water resistant layer 16 Hinge part M Mold H Heater f Thermoplastic film

Claims (4)

An inner molded body made of pulp mold,
An outer molded body consisting of a pulp mold that is substantially similar to the inner molded body and is superimposed on the outside of the inner molded body;
A water resistant layer made of a thermoplastic film spanned from the inner molded body to the outer molded body, and welded to the entire inner surface of the inner molded body and the entire outer surface of the outer molded body,
A pulp mold molded body , wherein a bridging portion of the water resistant layer from the inner molded body to the outer molded body is a hinge portion formed by a bent portion of a thermoplastic film .   The pulp mold molding according to claim 1, wherein the water resistant layer on the inner surface of the inner molded body and the water resistant layer on the outer surface of the outer molded body are welded. A step of parallelly arranging an inner molded body made of a pulp mold and an outer molded body made of a pulp mold that is substantially similar to the inner molded body, with a gap between them;
Spanning the thermoplastic film from the inner molded body to the outer molded body, and welding the entire inner surface of the inner molded body and the entire outer surface of the outer molded body;
And a step of superposing the outer molded body on the inside with the inner molded body on which the thermoplastic films are respectively welded, and a method for producing a pulp mold molded body.   The manufacturing method of the pulp mold molding of Claim 3 which further includes the process of welding the water resistant layer of the inner surface of the said inner molded body and the water resistant layer of the outer surface of the said outer molded body which were piled up.

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