JP2005288928A - Molded object with improved physical strength by dual layer molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure physical strength of a molded object in recycling a regenerated resin as a finished product. <P>SOLUTION: The molded object obtained by recycling the regenerated resin has one of the surface layers which is formed of a thermoplastic resin material and the other surface layer which is formed of a ground resin material as it is obtained by grinding the molded object processed using the thermoplastic resin material. Thus the molded object is dual-layered so that its mechanical strength and flame retardancy are improved. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to the physical property strength of a molded product when recycled resin is reused in a product.

  In particular, the present invention relates to a molded article having a two-layer molded structure formed of a material obtained by pulverizing a molded product in which one surface layer portion is formed of a thermoplastic resin material and the other layer portion is molded using a thermoplastic resin material. .

  The present invention also relates to a technique for pulverizing a molded article of the thermoplastic resin material and using the pulverized resin material as a resin raw material for injection molding.

  The present invention further relates to a technology for recycling plastic resin materials used in image forming apparatuses such as copying machines and printers, information communication equipment such as facsimile machines and computers, and home appliances.

  Products collected from the market have traditionally been decomposed and processed by incineration or landfill.

  In addition, when environmental problems become conscious, these plastic parts are reused by a technique of pulverizing and re-pelletizing them to the same level as unused resin materials. That is, as a recycling method for these materials, after molding products are pulverized, washed, and re-pelletized, unused resin materials (virgin pellets) and the above-mentioned used resin materials are mixed in a certain ratio. A method for taking measures to recover physical properties has been proposed. In addition, it is represented by an injection molding method having a sandwich structure composed of a resin molding part constituting a core layer and a resin molding part constituting a skin layer by injecting two kinds of resin materials into a cavity of a molding die. There is a reproduction method using a multi-layer structure.

As for these techniques using recycled resin, there are Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, and the like. Moreover, there exists patent document 5 etc. regarding mechanical strength. However, under these current recycling methods, the usage rate of the recycled material is as low as about 30%, and the recycled material cannot be used in a large amount in one molded product. In addition, sufficient mechanical strength is not clearly ensured. On the other hand, molded products made of 100% recycled material have sufficient strength for exterior parts, casings, and mechanical parts that are components of image forming equipment and information communication equipment such as copying machines, printers, and facsimiles. Absent.
JP 2002-86491 A Japanese Patent Laid-Open No. 5-301222 Japanese Patent Laid-Open No. 5-147036 JP 2000-108124 A JP 2002-347186 A

  The subject of this invention exists in the countermeasure against a fall of component intensity | strength when using a recycled material as a clue of the solution of said problem.

  That is, one of the objects of the present invention is to propose strength improvement by two-layer molding of a molded product using a recycled material.

  Further, another object of the present invention is to avoid deterioration of physical properties due to the heat history of the resin material to be reused by using the resin molded product to be reused as a pulverized material, and to further improve the strength by two-layer molding. Suggest improvements.

  These are composed of flat plate structures such as exterior parts, casings, and mechanical parts, which are constituent parts of image forming apparatuses and information communication apparatuses such as the above-described copying machines, printers, and facsimiles.

  Such a casing portion needs to guarantee mechanical strength. However, when 100% recycled material is used, it is difficult to obtain functional guarantee of the functional unit due to deterioration of physical property values of the recycled material. It was.

  In order to solve the above-mentioned problems, the present invention is a resin-molded product having a two-layer structure composed of one surface layer and another layer, and the resin material constituting a part of the other layer is formed from a thermoplastic resin material. We propose to improve the strength of a resin molded product with a two-layer structure in which the processed molded product is used as a pulverized resin material and the resin material constituting the surface layer is molded with a virgin material.

  In the above-mentioned invention, there is an embodiment of a resin molded product having a two-layer structure, wherein the resin molded product is an exterior part, a casing part or a component part of office equipment, electrical equipment, information communication equipment and the like.

  Further, the raw material of the resin material constituting a part of the other layer is a resin material obtained by pulverizing and processing office equipment exterior parts or office equipment casings and resin moldings of constituent parts. There is an embodiment of a resin molded product having a layer structure.

  Another aspect of the present invention is a resin molded product having a two-layer structure in which a resin material constituting one surface layer and a resin material constituting the other layer are respectively injected into a molding die. As the resin material that constitutes a part of the layer, a resin molded product obtained by molding a thermoplastic resin material is pulverized, and a resin material in which the size of the pulverized resin material is set to a predetermined size is used. We propose to improve the strength of resin molded products by the two-layer structure.

  The two-layered resin molded product is an exterior part, a casing part, or a component part of an image forming apparatus.

  Furthermore, another one of the present invention is a two-layered resin molded product composed of one surface layer and another layer, and the resin material constituting a part of the other layer is formed by molding a thermoplastic resin material. Using the pulverized resin material obtained by pulverizing the molded product, the resin material constituting the surface layer is molded with a virgin material, and the resin material constituting the surface layer is the same type of resin material as the pulverized resin material. We propose to improve the strength of resin molded products with a two-layer structure characterized by molding.

  Furthermore, another one of the present invention proposes improvement of the strength of a resin molded product by a two-layer structure characterized in that the thermoplastic resin material is a PC + ABS resin material.

  According to the present invention, a resin molded product having a two-layer structure composed of a surface layer and other layers, wherein the resin material constituting a part of the other layers is a molded product obtained by molding a thermoplastic resin material. The resin material of the two-layer structure is characterized in that the resin material constituting the at least one surface layer is molded using a virgin material, and the physical property deterioration due to thermal history is suppressed. The usage rate of the recycled material was high, and the strength of the molded product could be increased at a low cost without going through the repellet process.

  Further, the resin molded product can be proposed as a solution to environmental problems by using exterior parts or casing parts of office equipment, electrical equipment, information communication equipment, and the like.

(Example)
The evaluation methods are as follows for the following Examples 1-2 and Comparative Examples 1-2.

  Charpy impact test: Measurement according to JISK7111.

  Flame retardant test A test that complies with UL94 combustion test.

  PC-ABS virgin resin with a laminate thickness of 1m on one surface and PC + ABS recycled pulverized resin with a laminate thickness of 2mm on the other surface, a two-layer molded product (3mm in total) (Figure 1)

PC + ABS virgin resin with a laminate thickness of 1m on one surface and PC + ABS recycled resin with a laminate thickness of 2mm on the other surface, a two-layer molded product (3mm in total) (Figure 1)
(Comparative Example 1)
Molded product consisting of 3mm thick PC + ABS recycled crushed resin (Comparative Example 2)
Molded product consisting of 3mm thick PC + ABS recycled resin

A two-layer molded product with a total thickness of 3mm with PC + ABS recycled resin and a laminated thickness of 2mm on the other surface

Claims (3)

  A molded product made from recycled resin, with one surface layer made of a thermoplastic resin material and the other layer molded with a thermoplastic resin material. Molded product with improved mechanical strength and flame resistance.   A molded product made from recycled resin, with one surface layer formed from a thermoplastic resin material and the other layer formed from two layers of thermoplastic resin recycled material to provide mechanical strength and flame resistance. Improved molded product.   A two-layer molded article, wherein the thermoplastic resin material according to claim 1 or 2 is PC + ABS.

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