Method for manufacturing resin porous material

Abstract

To flatten porous materials that have become curved obtained by sintering granular resin without blocking surface pores.SOLUTION: A plate-shaped resin porous material is produced by integrally molding granular resin material into a plate of a predetermined thickness by sintering, leaving it at room temperature, heating it at 80°C to 100°C, and sandwiching it between highly flat plate members to cause plastic deformation. The sheet-shaped resin porous material is produced by obtaining the plate-shaped resin porous material, shaving a surface with a plane, heating the shaved sheet side again at 80°C to 100°C, and sandwiching it between highly flat plate members to cause plastic deformation.EFFECT: Whether the resin porous material is in the form of a plate or a sheet, it can be made flat and have a precise thickness while retaining its porosity after sintering.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a porous material obtained by sintering a resin. [Background technology]

[0002] Metal porous materials are expensive and heavy, so many resin porous materials are known, such as those disclosed in JP 2005-219985 A (Patent Document 1), which are made by sintering granular resin as the main material.Porous materials made by sintering granular resin as the main material are lighter than those made primarily from metal, and have the advantage of being cheaper due to the lower purchase price of the main material and the lower sintering temperature.

[0003] However, when it comes to porous materials made by sintering resin, even if a certain amount of pressure is applied during sintering, the horizontal surface does not become flat due to heating, and the center inevitably becomes curved and concave, making it impossible to make it flat, and the plate thickness could not be precisely controlled.

[0004] Therefore, currently, the surface of the porous material is polished after sintering, but when polishing is used to improve flatness and thickness accuracy, polishing debris can clog the pores on the surface, creating a new problem. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-219985 Summary of the Invention [Problem to be solved by the invention]

[0006] The problem to be solved is how to flatten the porous material obtained by sintering granular resin, which tends to curve, without blocking the surface pores. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention involves sintering granular resin material to form it into a plate material of a predetermined thickness, leaving it at room temperature, heating it to 80°C to 100°C, and sandwiching it between highly flat plate members to cause plastic deformation. [Effects of the Invention]

[0008] The present invention improves flatness and precisely controls thickness without polishing. Furthermore, because polishing is not required, polishing debris does not clog surface pores, and resin material is not wasted as polishing debris. Furthermore, since the resin does not melt or soften during heating and plastic deformation after sintering, the internal air bubbles are not crushed. Therefore, the intended porosity (specifications and performance such as average pore size and porosity) is maintained, improving flatness. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention achieves the objective of flattening the porous material obtained by sintering granular resin, which tends to curve, without blocking the surface pores, by sintering the granular resin material into a plate of a specified thickness, leaving it at room temperature, heating it to 80°C to 100°C, and sandwiching it between highly flat plate members to cause plastic deformation.

[0010] (Plate-shaped porous material) The porous material obtained by sintering granular resin is curved with a depression in the center. In this state, it is left to rest at room temperature to remove the heat generated during sintering and stabilize the curved shape. If this step is skipped and the material is immediately flattened after sintering, the internal air bubbles may be crushed.

[0011] After leaving it at room temperature, it is heated to 80 to 100°C. This heating is intended to plastically deform the porous material, which has still been curved up to this point, and is not intended to strengthen the bond by remelting or to modify the resin. Therefore, the heating temperature should be such that plastic deformation can occur.

[0012] The resin referred to in the present invention is a synthetic resin classified as a plastic, and most of them exhibit thermoplasticity at 80 to 100° C. In other words, 80 to 100° C. is the temperature at which plastic deformation is possible, and plastic deformation (curvature correction) is difficult at temperatures below 80° C., while variations in thickness and surface area may occur at temperatures above 100° C.

[0013] After heating to 80-100°C, the curved porous material is flattened by being sandwiched between highly flat plate members and plastically deforming it. The curvature is corrected by applying pressure between the highly flat plate members. The pressure (force) applied at this time varies depending on the resin material and the thickness of the porous material, but should be sufficient to correct the curvature by plastically deforming it, without causing thickness fluctuations (thinning) or cracking when pressed.

[0014] (sheet-shaped porous material) Furthermore, the present invention can also produce sheet-shaped porous materials by applying the above-mentioned method for producing plate-shaped porous materials. When attempting to obtain sheet-shaped porous materials by sintering granular resin, it is very difficult to form internal air bubbles by heating and pressurizing, making it extremely difficult to limit the thickness, for example, to 1 mm or less.

[0015] Furthermore, even if granular resin were sintered to obtain a sheet-shaped porous material of a specified thickness (for example, 1 mm or less), it would be subject to severe curvature (rolling) for the same reason as the plate-shaped porous material described above, making it difficult to commercialize in a flat state.

[0016] Therefore, in the present invention, rather than producing a sheet-shaped porous material from the beginning, it was considered to first produce a flat plate-shaped porous material and then form the plate-shaped porous material into a sheet. That is, in the present invention, a granular resin material is integrally formed into a plate of a predetermined thickness by sintering, left to stand at room temperature, heated at 80°C to 100°C, sandwiched between high-flatness plate members to cause plastic deformation to ensure the flatness of the plate-shaped porous material, and then the surface is shaved with a plane, and the sheet side shaved with the plane is heated again at 80°C to 100°C, sandwiched between high-flatness plate members to cause plastic deformation.

[0017] As described above, the process of sintering granular resin material into a plate of a predetermined thickness, leaving it at room temperature, heating it to 80°C to 100°C, and sandwiching it between highly flat plate members to cause plastic deformation is the same as the process of obtaining a flat, plate-shaped porous material, so explanations will be omitted.

[0018] After obtaining a flat plate-shaped porous material, the surface is shaved to a predetermined thickness (for example, 10 μm or less) using a plane. Here, the plane may be a manual sharp tool or an electric tool. When shaving the surface, there is a processing technique called surface cutting in mechanical processing, but in all of these, the base material is the main focus of finishing and processing, and the shape of the side cut from the base material (so-called cutting chips) is in the form of small pieces of chips. In contrast, when shaving the surface with a plane, although the main focus is of course finishing and processing the base material, the shape of the side cut from the base material is stable. In other words, in the present invention, the surface is shaved with a plane because the shape of the side cut from the base material is stable and sheet-like.

[0019] When the surface of a flat, plate-shaped porous material is scraped with a plane, a rolled, sheet-shaped porous material is obtained. This rolled, sheet-shaped porous material is heated to 80°C to 100°C, sandwiched between highly flat plate members, and plastically deformed to obtain a flat, sheet-shaped porous material. Note that the heating temperature range and the pressure range required for plastic deformation are the same as those for the plate-shaped porous material described above, so they are not described here.

[0020] In this way, an extremely thin and flat sheet-like porous material can be obtained. Furthermore, since the sheet-like porous material of the present invention is obtained by scraping the surface of a porous material that is originally in the form of a plate with a plane, the porosity does not deteriorate.

[0021] (Resin material) It is desirable to use ultra-high molecular weight polyethylene (UHMWPE) as the main resin for the above-mentioned plate- and sheet-shaped porous materials. This is because it has high impact resistance, abrasion resistance, lubricity, and chemical resistance, is lightweight, has stable chemical and physical shapes, and is easy to cut with a plane, especially when obtaining sheet-shaped porous materials.

[0022] This ultra-high molecular weight polyethylene can be used to make plate- or sheet-shaped porous materials. For example, if these materials are used as air blowing components for floating tiny electronic components in industrial machinery that floats and transports these components, compared to conventional metallic porous materials, they will have the same performance as metal, but are lighter in weight, reducing the load on the drive unit and enabling the industrial machinery as a whole to be made smaller and more cost-effective.

Claims

1. A method for manufacturing a resin porous material in which granular resin material is sintered to form a plate of a specified thickness, left at room temperature, heated to 80°C to 100°C, and sandwiched between highly flat plate members to plastically deform the material.

2. A method for producing a sheet-like resin porous material, in which granular resin material is integrally formed into a plate material of a predetermined thickness by sintering, left to stand at room temperature, heated at 80°C to 100°C, sandwiched between highly flat plate members to cause plastic deformation, the surface is then shaved with a plane, and the sheet side that has been shaved with the plane is heated again at 80°C to 100°C, and sandwiched between highly flat plate members to cause plastic deformation.

3. 3. The method for producing a resin porous material according to claim 1, wherein the granular resin material is ultra-high molecular weight polyethylene (UHMWPE).