JP3443704B2 - Hollow plate-like structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic hollow plate structure used as a constituent material of furniture, automobiles, etc., or a construction material.

[0002]

2. Description of the Related Art Conventionally, plastic hollow plate-like structures used for this type of application have been manufactured by blow molding of thermoplastics or other molding methods.

[0003]

In general, thermoplastic plastics are mass-produced because they are excellent in raw materials, easy to process, and low in cost. For this reason, on the other hand, the amount of plastic products discarded is enormous, and in the waste treatment,
Reuse and weight reduction are important issues. Plastic waste includes general waste such as used containers generated by general consumption, burrs of molded products generated in production processes such as production plants and test processes, defective molding waste products, and waste products after testing. It is divided into industrial waste.
Municipal waste is called recycled resin and is made into a resin material through recovery, removal of dirt and foreign substances, crushing process, etc.
It is unavoidable that dirt and foreign substances remain, and it is a low quality plastic material. On the other hand, industrial waste has less dirt and foreign substances like general waste,
Reuse is relatively easy and a considerable amount has already been reused. However, after a history of repeated repeated heating and melting, fluidity changes and carbonization phenomenon appears, and for example, in blow molding, drawdown occurs and the wall thickness becomes uneven, and surface deterioration appears. . And, in reality, these factors hinder the reuse of plastic waste.

In view of such problems in recycling plastic waste, the present invention maintains high quality such as good appearance of the product and required strength, and more particularly, in general. It is an object of the present invention to provide a hollow plate-like structure capable of promoting the utilization of recycled resin mainly composed of waste.

[0005]

In order to achieve the above object, a hollow plate-like structure according to the present invention has a hollow portion formed by blow molding a thermoplastic resin so that a front wall and a back wall are integrally formed. In a continuous hollow plate-shaped structure, all the walls forming the hollow plate-shaped structure are made of a recycled resin layer, and the outer surface of the surface wall, which is the design surface , of the walls made of the recycled resin layer is a virgin resin layer. And the thickness ratio of the recycled resin layer and the virgin resin is 98: 2 to 75:25. The recycled resin that constitutes a part of the constituent wall of the hollow plate-shaped structure in the present invention can be mainly composed of recycled resin.

[0006]

The hollow plate-like structure according to the present invention has a structure in which all the walls forming the hollow plate-like structure are made of a recycled resin layer, and the outer wall of the designed surface out of the walls made of the recycled resin layer. The surface is a virgin resin layer, and the thickness ratio between the recycled resin layer and the virgin resin is 98: 2 to 75:25. A portion which has a good surface and is not required to have an external appearance can be used as a recycled resin, and the amount of the recycled resin used can be increased.

[0007]

Embodiments of the present invention will be described with reference to the drawings. Figure 1
As an example of the hollow plate-shaped structure, a console lid, which is an interior part of an automobile, is illustrated in FIG. As shown in FIG. 1, the console lid 1 has a front wall 2 integrally formed with a virgin resin layer and a rear wall 3 integrally formed with a recycled resin layer.

The console lid 1 is manufactured by blow molding as shown in FIG. In FIG. 2, 4 and 4 are split molds, 5 and 5 are cavities, and 6
Is an extrusion head and 7 is a parison. As shown in FIG. 3, the parison 7 has a two-layer structure in which a portion forming the front surface wall 2 of the console lid 1 has a virgin resin layer 8 and a portion forming the back surface wall 3 has a regenerated resin layer 9, and a plurality of extrusions are formed. Virgin resin layer 8 that has been melted and kneaded by a machine (not shown)
The reclaimed resin layer 9 and the reclaimed resin layer 9 are extruded from the extrusion head 6 in a state of being integrally provided. The tubular parison 7 formed by the extrusion head 6 is mainly composed of a recycled resin layer 9 of at least 50%. The virgin resin layer 8 of the parison 7 is a thermoplastic resin that does not undergo a thermal history due to molding, and may contain less than 10% recycled resin in some cases. The recycled resin layer 9 is a thermoplastic resin that has undergone a heat history due to molding at least once, and is particularly a recycled resin layer recovered as general waste.

In the blow molding process shown in FIG. 2, since the parison 7 in which the virgin resin layer 8 and the recycled resin layer 9 are integrally connected is used as shown in FIG. 3, the parison 7 has the recycled resin layer 9. And the other part is the virgin resin layer 8
Drawdown not occur since it is, also, the front surface <br/> wall 2 of the shaped article since it is composed of a virgin resin layer 8 comes to have a good appearance. In the embodiment shown in FIG.
Since the proportion of recycled resin in the entire molded product is large, it contributes greatly to the expansion of the use of recycled resin.

FIG. 4 shows an embodiment of the present invention. In this embodiment, the hollow plate-shaped structure according to the present invention is used as the top plate 11 of the desk 10. Reference numeral 12 denotes a desk leg made of metal or hard plastic pipe.

As shown in FIG. 5, the top plate 11 of the desk 10 shown in FIG. 4 is made of a recycled resin layer on all the walls forming a hollow plate-like structure, and the top wall 13 and the side walls 14 are The outer surface layer 15 is a virgin resin layer. The thickness ratio of the recycled resin layer and the virgin resin is 98: 2 to 2:98.
However , it is preferably 98: 2 to 75:25 . The top plate 11 is also blow-molded as shown in FIG. 2, and the parison 16 has a virgin resin layer 18 integrated with a part of the surface of the recycled resin layer 17, as shown in FIG. .

As shown in FIGS. 4 and 5, only the upper surface 13 and the side surface 14 of the top plate 11 which is a hollow plate-like structure are used as the virgin resin layer 18, and most of the other is the recycled resin layer 17.
As a result, the ratio of recycled resin used can be further increased,
It is possible to further improve the utilization promotion of the recycled resin.

The hollow plate-like structure according to the present invention is represented by polyolefins such as polyethylene and polypropylene, polyethylene terephthalate, polyethylene isophthalate, polyethylene 2,6-naphthalate, polybutylene terephthalate and copolymers thereof. Polyester resins, polyether resins such as polyoxymethylene, nylon-6, nylon 66
Polyamide resin represented by, for example, polyvinyl chloride, polystyrene, poly (meth) acrylic acid ester, polyacrylonitrile, polyvinyl acetate represented by vinyl acetate and their copolymers, polycarbonate resin, cellophane , Cellulose resins such as acetate, and engineering resins such as polyphenylene oxide.

The hollow plate-like structure according to the present invention is a structure in which a front wall and a back wall each having a hollow portion inside are integrally connected to each other, and a flat plate-like structure such as a panel, a top plate or a door. , Bowl-shaped structures such as containers and lids. The front wall of this hollow plate-like structure forms a design surface and its appearance is prioritized, but the back wall is prioritized in function over appearance. Further, the virgin resin in the present invention, a simple substance of a resin which has not been subjected to a heat history by molding, and a mixture of a resin which has not been subjected to a heat history of the molding and a resin which has not been subjected to a heat history of another molding, or It refers to a mixture containing less than 10% of the regenerated resin in a range in which the properties of the resin not subjected to the heat history due to molding are not impaired. Further, the reclaimed resin in the present invention means a simple substance of a resin that has undergone heat history by molding, a mixture of a resin that has undergone heat history by molding and a resin that has undergone heat history by molding, or less than 50%. Of virgin resin.

[0015]

EFFECTS OF THE INVENTION According to the present invention, a hollow plate-like structure is obtained by blow-molding a thermoplastic and having a hollow portion inside and integrally forming a front wall and a back wall. All the walls are made of a recycled resin layer, and the outer surface of the front wall forming the design surface of the wall made of the recycled resin layer is a virgin resin layer, and the thickness ratio of the recycled resin layer and the virgin resin is 98: Since it is set to 2 to 75:25, only the surface of the hollow plate-shaped structure is used as the virgin resin layer, and most of the other is used as the recycled resin layer, so that the usage ratio of the recycled resin can be further increased and the utilization of the recycled resin can be further promoted. The effect which can be improved is acquired.

[Brief description of drawings]

FIG. 1 is a cutaway perspective view showing a part of an automobile console lid which is a hollow plate-shaped structure according to the present invention.

FIG. 2 is a vertical cross-sectional view showing a blow molding aspect of the one shown in FIG.

FIG. 3 is an enlarged sectional view of the parison in FIG.

FIG. 4 is an overall perspective view of a table including a top plate that is a hollow plate-like structure according to the present invention.

5 is a cutaway enlarged perspective view showing a part of the top plate of FIG. 4. FIG.

6 is a cross-sectional view of a parison for blow molding the top plate of FIG.

[Explanation of symbols]

1 Car console lid 2 surface wall 3 Back wall 4,4 split mold 5,5 cavity 6 extrusion head 7 Parisons 8 Recycled resin layer 9 Virgin resin layer 10 desks 11 Top plate 12 desk legs 13 Upper surface 14 sides 15 Outer surface layer 16 Parison 17 Recycled resin layer 18 Virgin resin layer

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B29C 49/22 ZAB

Claims (2)

(57) [Claims] 1. A hollow plate-shaped structure in which a thermoplastic resin is blow-molded to have a hollow portion inside and a front wall and a back wall are integrally continuous, and all walls forming the hollow plate-shaped structure are made of a recycled resin layer. Of the wall made of recycled resin layer
The outer surface of the surface wall forming the design surface is a virgin resin layer, and the thickness ratio of the recycled resin layer and the virgin resin is 98: 2 to 75:
25. A hollow plate-like structure characterized by being 25. 2. The hollow plate-shaped structure according to claim 1, wherein the recycled resin forming part of the wall of the hollow plate-shaped structure is mainly composed of recycled resin.