JP2011178092A - Method of manufacturing heat insulating board or the like using rice hull or the like as raw material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To overcome problems that in many cases a heat insulating board or the like is difficult to maintain a sufficient strength due to a moisture content remaining after hot forming in a method of manufacturing the heat insulating board or the like such as a heat insulating material and a sound insulating material using rice hull etc. as a raw material, a heating and a cooling over a long time must be carried out inefficiently, further a strength degradation due to the remaining moisture content invites a breakage after shaping, and a defective fraction is high, and on the other hand, problems that in a method of taking out a molding after solidifying by a freezing or the like, etc., an equipment burden is large and it is difficult to manufacture at low costs. <P>SOLUTION: An effective water removal is carried out by repeating an operation of a pressurization and a relief of the pressure, by which a heating and drying speed up while suppressing the occurrences of a defect, and the size and the density of the molding are stabilized early by a stopper controlling a press amount depending on the molding density. Further, the breakage of the molding is suppressed using a mold subjected to a fluorine processing or the like having a good mold releasability, which constitutes an efficient press production method to solve the problems. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a heat insulating board or the like using rice husk or the like as a raw material.

  Insulation boards made from rice husks, etc., which are agricultural wastes, and insulation boards such as sound insulation boards and surface materials have attracted attention because of their light weight and low environmental impact. Many are mixed with a non-polluting adhesive, put into a mold, etc., heated and pressed, and then cooled or naturally dried, or frozen and kept in shape, and then thawed and dried. (For example, Patent Document 1 or 2).

Japanese Patent Laid-Open No. 6-8968 JP 2008-260201 A

  In many cases of molding such a heat insulating board, it is often the case that the heat insulating board does not maintain sufficient strength due to moisture remaining after heat forming, and heating and cooling over a long period of time must be performed. It was inefficient. In addition, a decrease in strength due to residual moisture causes damage after molding, resulting in a high defect rate. In addition, there is a method in which the molded product is frozen and taken out as described in Patent Document 2, and then thawed and dried. However, it is difficult to introduce the method because the number of steps increases and the equipment scale increases.

  The present invention is a method for manufacturing a heat insulating board or the like that is formed by heat-pressing a raw material mixed with rice husks and an adhesive with a mold, and effectively removes moisture by repeating the operation of pressurization and depressurization. The present invention provides a pressing method that speeds up heating and drying while suppressing generation.

  In the method for manufacturing a heat insulating board or the like described in paragraph 0005, a replaceable external stopper may be provided outside the mold for the purpose of keeping the density and thickness of the molded product constant.

  In addition, in the method of manufacturing a heat insulating board or the like described in paragraph 0005, in order to reduce friction and adhesion between the mold and the molded product during molding, the mold is taken out by taking a mold release measure such as fluorine processing, and the molded product is taken out. May be configured to facilitate.

  According to the present invention, the time required for heating and drying during molding can be shortened, and a molded product can be obtained with a stable arbitrary size and density. In addition, a highly efficient production effect with a reduced defect rate can be obtained.

Molding method according to the invention

  A molding method according to the present invention is shown in FIG. The raw material 1 is a mixture of agricultural waste such as rice husk and an adhesive. The mold 2 has a surface processed with fluorine and is preferably made of a material having excellent heat conduction. The outer frame may be provided with an opening / closing or disassembling mechanism so that the molded product can be more easily taken out. As a heat source for the hot press 3, in addition to using electric heat or steam heat, high-frequency heating may be performed. The hot press 3 may be provided with an external stopper 4 that stops at a predetermined height when lowered, and in this case, the hot press 3 is configured to be easily exchanged so that the press height can be changed.

  A manufacturing example according to the present invention will be described. As an example, when an insulation board is to be molded, an external stopper 4 is provided to obtain a molding thickness corresponding to the density of the insulation board. Then, a predetermined amount of the mixed raw material 1 is put into a mold 2 and scraped and placed in a hot press 3.

  When the press is lowered, the thickness of the molded product is kept constant by the external stopper 4. This makes it possible to perform a constant molding with an arbitrary density and thickness without changing the mold or pressure. After the heating press for a certain time, the hot press 3 repeats the operation of hunting for releasing the pressure once and pressurizing it again. As a result, moisture contained in the raw material evaporates at the time of decompression, and speeds up drying. Thereafter, the hot press 3 rises and opens.

  According to the present invention, it is possible to efficiently produce a high-quality heat insulation board with a low defect rate and a high quality with a relatively small equipment burden. In particular, rice husks must be treated as waste as an expensive process, and thus are very effective as a method for producing molded products using environmentally friendly materials at low cost.

1: Raw material 2: Mold 3: Hot press 4: External stopper

Claims (3)

In a method for manufacturing a heat insulating board or the like in which a raw material in which rice husks and an adhesive are mixed is hot-pressed with a mold, the water is effectively removed by repeating the operations of pressurization and depressurization. Method. 2. The pressing method according to claim 1, wherein a stopper for fixing the height during pressurization is provided outside the mold in order to keep the density and thickness of the molded product constant. 2. The manufacturing method according to claim 1, wherein the mold product is easily taken out by taking measures against mold release such as fluorine processing and reducing friction and adhesion between the mold and the molded product during molding. Method.

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