JPH0516383B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a continuous pore-forming resin molded article that has continuous pores evenly distributed and has excellent strength, and a method for producing the same.

[Conventional technology]

Conventionally, pore-forming resin molded products have been produced using a foaming method in which a foaming agent is added to a resin liquid (undiluted solution) of a synthetic resin and pores are formed by foaming the foaming agent.
When mixing the stock solution and the inorganic filler, a large amount of the inorganic filler is added and pores are formed between the particles of the inorganic filler to obtain a porous body.

[Problem that the invention seeks to solve]

However, in the porous body formed by the above method, the pores are generated by foaming with a foaming agent, so the size of the pores in the porous body is uneven and the strength is low. Since a resin skin layer is formed on the body surface, the pores that are generated either become finer in the skin layer or do not form communicating pores that communicate with the outside. In addition, when manufacturing a porous body by increasing the amount of inorganic filler as in the above method, pores are formed in the gaps between particles of the inorganic filler, resulting in uneven pores (inner pores are larger in diameter). The problem is that the surface side becomes smaller). In addition, in this case, a considerable amount of air is likely to be drawn into the molded product during mixing, making it difficult to obtain a uniform, highly dense porous body. As described above, a high-strength porous body with water permeability could not be obtained using conventional methods.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a resin molded product with continuous pores that is excellent in strength and a method for manufacturing the same.

[Means for solving problems]

In order to achieve the above object, the present invention contains multiple types of inorganic fillers having mutually different particle sizes distributed in a close-packed state in a base material mainly made of synthetic resin, and The first aspect is a resin molded product with continuous pores formed in it, which is mainly made of synthetic resin containing multiple types of inorganic fillers and volatile substances with mutually different particle sizes. A continuous pore-forming resin molded article, characterized in that when a resin liquid is prepared, and the resin liquid is polymerized and cured to form a cured body, the volatile substance is volatilized and removed, and the trace of the removal is formed into continuous pores. The second gist is the manufacturing method.

That is, in order to achieve the above object, the present inventor has conducted research focusing on the particle size of the agent used for pore formation and the inorganic filler used. The present inventors have discovered that when a volatile substance is used as a pore-forming agent, a high-strength continuous pore-forming resin molded article can be obtained, and the present invention has been achieved.

The continuous pore-forming resin molded article of the present invention is obtained using a plurality of types of inorganic fillers having mutually different particle sizes, a volatile substance, and a resin liquid mainly composed of synthetic resin.

Examples of the synthetic resin include thermosetting resins such as epoxy resins and polyester resins, polyolefin resins such as high-density polyethylene, and thermoplastic resins such as vinyl chloride.

Examples of the volatile substances include low molecular weight substances such as alcohols and glycols.

Further, examples of the inorganic filler include quartz, alumina, etc., and in particular, a plurality of types of fillers having different particle sizes are used. As a combination of multiple types of different particle sizes, for example, a mixture of three types, larger than 100 μm (A), 30 to 100 μm (B), and less than 30 μm (C), has a weight ratio of A/B/C= 1/2/
1. Another example is a combination in which a mixture of two types, one larger than 100 μm (A) and one smaller than 30 μm (C), is set at a weight ratio of A/C=1/2. Note that these combinations are not limited.

The continuous pore-forming resin molded article of the present invention is manufactured using the above-mentioned raw materials, and is useful as a mold for products such as concrete and ceramics. Such a resin molded article with continuous pores can be produced, for example, in the following manner. That is, multiple types of inorganic fillers and volatile substances with different particle sizes are added and mixed to a resin liquid mainly composed of the above synthetic resin, and after casting into a predetermined mold, bubble formation treatment is performed in a semi-cured state. I do. The blending amount of each of the above raw materials is 200 to 800 parts, preferably 300 to 600 parts of the inorganic filler, and no volatile substances to 100 parts by weight of the synthetic resin liquid (hereinafter referred to as "parts"). The amount is 10 to 50 parts, preferably 20 to 30 parts. When performing this bubble formation treatment, if the synthetic resin that is the main component of the base material is a thermosetting resin, heating (80°C or higher) by irradiation with electromagnetic waves and far infrared rays, etc. When the synthetic resin is a thermoplastic resin, the bubble forming treatment is performed by heating under reduced pressure using the method described above. During this heating, the volatile substances vaporized and gasified by the heating pass between multiple types of inorganic fillers with different particle sizes, thereby forming uniform and fine continuous pores.
Moreover, since multiple types of inorganic fillers with different particle sizes are distributed in the base material in a close-packed state, a continuous pore-forming resin molded product with excellent strength can be obtained. Here, the above-mentioned closest packing state means that the total 50% of the inorganic filler is
At least 70% by weight, preferably at least 70% by weight,
This means that the particles are distributed with close spacing between them.

Such a resin molded product with continuous pores is used for the following purposes. For example, in a molding apparatus as shown in FIG. 1, a resin molded article 1 made of a synthetic resin sponge and having continuous holes, which is a product of the present invention, is disposed inside an upper frame 3 having a U-shaped cross section. used as such. A vacuum suction pipe 5 extends inside the molded product 1 for the upper mold.
This vacuum suction pipe 5 is provided with a plurality of openings at predetermined intervals. The end of the vacuum suction pipe 5 is connected to a vacuum suction pump (not shown) via a connecting pipe (not shown), and a cutoff valve is provided in the middle of this connecting pipe. Reference numeral 4 denotes a lower frame body having a U-shaped cross section, and is provided with a molded product 2 for the lower mold similar to the molded product 1 for the upper mold. A vacuum suction pipe 6 having a structure similar to that described above is also provided in the molded product 2. This vacuum suction pipe 6
is connected to a vacuum pump (not shown) and a compressed air delivery pump (not shown) via a switching valve provided in a connecting pipe (not shown). The upper molds 1, 3 and the lower molds 2, 4 are moved up and down to open and close the molds by a conventionally known mold opening/closing device (not shown). Furthermore, a press inlet 9 is formed in the side surface of the lower molds 2 and 4 for press-fitting the raw material slurry 7 into the molding space created by the molded product 1 and the molded product 2.

In this configuration, the raw material slurry 7 is press-fitted from the press inlet 9 with the mold closed as shown in the figure. At the same time, vacuum suction is performed from the vacuum suction pipe 5 of the upper mold and the vacuum suction pipe 6 of the lower mold, and moisture is discharged to the outside through the communicating holes of the molded products 1 and 2 of the upper mold and the lower mold. This operation is continued until the molding space is filled with the molded article. Next, when the molded product has sufficient strength, compressed air is discharged from the vacuum suction pipe 6 of the lower mold, and at the same time, the upper mold is lowered while continuing suction with the suction pipe 5. Raise it relative to the mold (see Figure 2). Thereby, the molded article 8 rises while being adsorbed to the surface of the molded article 1 of the upper mold. Then, in this state, a saucer (not shown) is inserted between the upper mold and the lower mold to cut off the vacuum suction of the upper mold. As a result, the molded body 8
is detached from the surface of the molded product 1 and falls into the receiving tray.

In this way, concrete and ceramic molded bodies can be efficiently produced using the product of the present invention, and the product of the present invention is extremely useful as a molding material for these.

〔Effect of the invention〕

As described above, the present invention produces a cured product by polymerizing and curing a resin liquid mainly composed of synthetic resin in which multiple types of inorganic fillers and volatile substances having different particle sizes are uniformly distributed. In order to manufacture a resin molded product with continuous pores by heating and volatilizing volatile substances and turning the removed residue into pores,
The resulting continuous pore-forming resin molded product not only has high strength and uniform fine pores, but also has water permeability because the formed pores become continuous pores. Therefore, the continuous pore-forming resin molded product of the present invention is extremely useful as a molding material for concrete products and the like.

Next, the present invention will be explained in detail based on examples.

Example 1 600 parts of three types of inorganic fillers (quartz powder) with different particle sizes were added to 100 parts of an epoxy resin liquid (weight ratio: 100 μm</30 to 100 μm/30 μm>=1/
2/1) At the same time as blending, add ethyl alcohol
20 parts were blended, mixed, and cast into a predetermined mold. Next, the mold together with the mold was heated to harden the resin and at the same time volatilize the ethyl alcohol, yielding molded products 1 and 2 having shapes as shown in FIG. This product showed good performance as a water-permeable type.

Example 2 600 parts of two types of inorganic filler (alumina) with different particle sizes (weight ratio: 100 μm</30 μm> = 1/2) and 30 parts of ethylene glycol were added to 100 parts of epoxy resin liquid. , mixed and cast into a predetermined mold. After this, molded products 1 and 2 were obtained in the same manner as in Example 1. This product showed good performance as a water-permeable type.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a molding apparatus using a molded article according to an embodiment of the present invention as a mold, and FIG. 2 is an explanatory diagram of its operation. 1... Molded product for upper mold, 2... Molded product for lower mold, 3, 4... Frame, 5, 6... Vacuum suction pipe, 7... Raw material slurry, 8... Molded product, 9 ……
Pressure inlet.

Claims (1)

[Claims] 1. Multiple types of inorganic fillers with mutually different particle sizes are distributed and contained in a close-packed state in a base material mainly made of synthetic resin, and communicating pores are formed between the inorganic filler particles. A resin molded product with continuous pores. 2. When preparing a resin liquid mainly composed of synthetic resin containing multiple types of inorganic fillers and volatile substances with mutually different particle sizes, and polymerizing and curing this resin liquid to form a cured body, the above-mentioned volatile A method for manufacturing a resin molded product with continuous pores, characterized by removing a substance by volatilization and forming continuous pores in the residue left after the removal.