JPH06278109A - Wooden board and production thereof - Google Patents

Abstract

PURPOSE:To obtain wooden board excellent in bending strength and the retentivity of bending strength at a time of wetness by utilizing a husk of corn. CONSTITUTION:Wooden board is obtained by a method wherein an adhesive is added to and mixed with a base material partially or wholly constituted of a husk of corn and the resulting mixture is subjected to compression molding under heating to be formed into a board shape. The adhesive is added to and mixed with the base material constituted of small wood pieces and the husk of corn and the resulting mixture is subjected to compression molding under heating to be formed into the board shape. By this method, wooden board excellent in bending strength and the retentivity of bending strength at a time of wetness can be inexpensively obtained without damaging the characteristics of conventional wooden board.

Description

Detailed Description of the Invention [Object of the Invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to wood boards using corn hulls and having excellent flexural strength and retention of flexural strength when wet, and a method for producing the same.

2. Description of the Related Art Conventionally, the raw material for wood boards such as particle boards, fiber boards, hard boards, MDF and insulation boards is wood.
Currently, most of the raw timber depends on imports. However, in recent years, there has been a great demand for timber, and deforestation has spread to primeval forests, and deforestation has become a problem. Under such circumstances, there is a worldwide call for forest protection and nature protection. It is inevitable that imports will decrease relative to demand. On the other hand, conventionally, corn hulls are obtained as a by-product when purifying starch from corn kernels,
A soluble component protein (corn steep liquor) concentrate obtained by the wet milling method and other components were added and dried to obtain a corn gluten feed, which was incorporated into a feed for livestock. However, in recent years, the quality of livestock feed has improved, and nowadays there is almost no utilization of corn husks, and about 500 to 550,000 tons of corn husks remain unused each year, which is a problem in disposing of them. is there.

Therefore, about 50 to about a year
Since 550,000 tons of corn husks are left unused and difficult to dispose of, we examined wood boards that use cheap corn husks instead of raw wood for the production of boards as a method of using this corn husk. . That is, an object of the present invention is to provide an inexpensive wooden board and a method for manufacturing the same, without impairing the characteristics of conventional wooden boards.

[Constitution of the invention]

Means for Solving the Problems The wood boards according to the present invention are obtained by adding and mixing an adhesive to a base material which is partially or wholly composed of corn husk, and then forming and heating and compression molding. is there. Further, in the method for producing wood boards according to the present invention, an adhesive is added to and mixed with a base material composed of small pieces of wood and corn hulls, followed by heating and pressing. The present invention relates to boards and a method for producing the same as a method of using corn hulls, wherein a part or the whole amount of the base material is composed of corn hulls, and the composition ratio of the corn hulls to the base material is 10%. ~ 100% by weight. The composition of the corn hull and the base material is not particularly limited, and the mixture may have a two-layer structure, a three-layer structure, or a single plate, impregnated paper, or the like may be laminated on one or both surfaces thereof. Also, the thickness and density of the board can be set arbitrarily according to the purpose of use,
Usually, the board has a thickness of 2 to 50 mm and a density of 0.4 to 1.
5 g / cm ³ is desirable. The adhesive used in the production of boards by utilizing the corn hull of the present invention,
The phenol resin, resorcin resin, urea resin, urea-melamine co-condensation resin, isocyanate resin and the like are not particularly limited. The range of the amount of the adhesive added is not particularly limited, but is preferably 5 to 20% by weight with respect to the base material. If necessary, additives such as a water repellent, a release agent, a formalin catcher agent, a preservative, a curing agent, a curing accelerator and a curing inhibitor can be added. Boards using corn hulls of the present invention,
It can be manufactured at low cost by a manufacturing method as shown in Examples described later.

EXAMPLES The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these examples. In addition, "part" or "%" in the examples is based on weight unless otherwise specified. [Example 1] 100 parts of corn hulls are put into a blender, and 10 parts of urea resin in solid content is sprayed onto a base material with a spray gun while mixing, and mixed. The thickness of the mixture after molding is 15 mm and the density is 0.8.
Formed to g / cm ^3, and after preforming 15
Heat compression using a distance bar at 0 ° C for 30 minutes,
Got the board. [Example 2] A liquid phenolic resin of 10 parts in solid content was added and mixed in the same manner as in Example 1 with respect to 100 parts of corn hull, and the thickness after molding was 15 mm and the density was 0.8 g.
/ Cm ³ and forming under the same conditions as in Example 1 to obtain a board. [Example 3] A liquid phenol resin of 8 parts in solid content was added and mixed with 100 parts of corn rind in the same manner as in the above-mentioned Example 1, and a 1.2 mm-thick veneer was applied on both sides at the time of forming and 150 ° C. At 30 ° C. for 30 minutes using a distance bar to obtain a single plate-clad board having a thickness of 15 mm and a density of 0.6 g / cm ³ . [Example 4] To 100 parts of corn hulls, 8 parts of solid type isocyanate resin was added and mixed in the same manner as in the above Example 1, and the thickness after molding was 15 mm and the density was 0.6 g.
/ Cm ³ and forming at 150 ° C for 20
A board was obtained by heating and compressing using a distance bar for minutes. [Example 5] 50 parts of corn hull and 50 wood chips
To the mixture of 1 part, 10 parts of solid content urea-melamine resin was added and mixed in the same manner as in Example 1, and the thickness after molding was 1
Forming was carried out so that the density was 5 mm and the density was 0.8 g / cm ^3, and the board was obtained by heating and compression at 150 ° C. for 30 minutes using a distance bar. [Example 6] To a mixture of 50 parts of corn hull and 50 parts of wood fiber, 10 parts of liquid phenol resin in solid content was added and mixed by the same method as in Example 1,
After forming, the board was formed into a thickness of 5 mm and a density of 0.8 g / cm ^3, and was heated and compressed at 150 ° C. for 10 minutes using a distance bar to obtain a board. [Comparative Example] To a mixture of 100 parts of wood chips, 10 parts of urea resin in solid content was added and mixed in the same manner as in Example 1 so that the thickness after molding was 15 mm and the density was 0.8 g / cm ^3. Then, the board was obtained by heat-compressing with a distance bar at 150 ° C. for 30 minutes. The molded boards obtained in Examples 1 to 6 and Comparative Example were JIS
Bending strength and wet bending strength were measured in accordance with the measuring method of A 5908, and the results are shown in Table 1 below.

[Table 1] As is clear from the results in Table 1, the wood boards according to the present invention show excellent flexural strength and retention of flexural strength when wet. Here, the method for calculating the flexural strength retention rate when wet is retention rate (%) = (flexural strength when wet / flexural strength) ×
100.

EFFECTS OF THE INVENTION The wood boards manufactured by utilizing corn hulls as a part or the whole amount of the base material in the present invention have bending strength equal to or higher than that of the board manufactured using the wood base material, The retention of bending strength when wet is also high. The present invention enables effective use of resources. Also,
Since the manufacturing method of the present invention effectively uses the corn hull which is difficult to dispose of, it is possible to manufacture wood boards having the above-described effects at low cost. The present invention as described above enables effective use of resources.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masami Ando 700 No. 700, Tadashi-cho, Takasaki-shi, Gunma Gunei Chemical Industry Co., Ltd.

Claims (2)

[Claims] 1. A wood board obtained by adding and mixing an adhesive to a base material of which a part or the whole amount is made of corn hull, followed by forming by heating and compression molding. 2. A method for producing wood boards, which comprises adding and mixing an adhesive to a base material composed of small pieces of wood and corn hulls, and heating and pressing after forming.