JP6027489B2 - Manufacturing method of wood fiberboard - Google Patents

Description

  The present invention relates to a method for manufacturing a wood fiber board.

  Conventionally, a wood fiber board having moisture permeability has been used as a wall material in a room such as a house.

  As a method for producing a wood fiber board, for example, a powder resin is supplied to wood fibers on a conveyor, and a fiber mat is produced by defibrating with a rotating defibrating cylinder (roll with a needle). A method for producing a wood fiber board by pressure molding is known (Patent Documents 1 and 2).

JP-A-5-51466 Japanese Patent Laid-Open No. 5-220878

  However, in the case of the conventional methods such as Patent Documents 1 and 2, a part of the powder resin supplied to the wood fiber may be scattered around by centrifugal force during defibration by the defibrating cylinder. . In this case, since the scattered powder resin is difficult to use in the process of manufacturing the fiber mat, there is a problem that material loss cannot be avoided.

  The present invention has been made in view of the circumstances as described above, and the loss of powder resin that scatters when a fiber mat is manufactured by defibrating wood fiber and powder resin, which are the materials of the wood fiber board. It is an object of the present invention to provide a method for manufacturing a wood fiber board capable of suppressing the above-described problem.

  In order to solve the above-described problems, a method for producing a wood fiber board of the present invention includes the following steps, a laminate step of supplying a powder resin from a resin supply unit on a wood fiber to form a laminate, and the laminate A method for producing a wood fiber board, comprising a defibrating step of defibrating a body with a defibrating cylinder to obtain a fiber mat, and a molding step of producing a wood fiber board by hot pressing the fiber mat, The defibrating cylinder has suction means inside, and has a plurality of small holes leading to the inside on the surface, and the suction of the powder resin scattered by defibration of the laminated body to the suction of the defibrating cylinder It is characterized in that it is sucked and collected inside by means and re-introduced into the resin supply section.

  In this wood fiber board manufacturing method, it is preferable to supply dehumidified air in the defibrating step.

  In this wood fiber board manufacturing method, it is particularly preferable that the wood fiber layer in the laminating step contains a liquid material.

  According to the method for producing a wood fiber board of the present invention, when a fiber mat is produced by defibrating wood fibers and a powder resin, which are materials of the wood fiber board, the loss of the scattered powder resin can be suppressed. it can.

It is the schematic which illustrated one Embodiment of the manufacturing method of the wood fiber board of this invention.

  FIG. 1 is a schematic view illustrating an embodiment of a method for producing a wood fiber board of the present invention. Hereinafter, one embodiment of the method for producing a wood fiber board of the present invention will be described with reference to FIG.

  The manufacturing method of the wood fiber board of this invention includes the following processes.

  (1) A lamination process in which a powder resin is supplied from a resin supply unit on a wood fiber to form a laminate.

  (2) A defibrating step of defibrating the laminate with a defibrating cylinder to obtain a fiber mat.

  (3) A molding step for producing a wood fiber board by hot-press molding the fiber mat.

  In the laminating step, the powder resin 2 is supplied from the resin supply unit D2 on the wood fiber 1, and the laminate 3 in which the powder resin 2 is laminated on the wood fiber 1 is formed.

  Specifically, the wood fiber 1 is supplied onto the conveyor C from the upstream fiber supply unit D1. The supplied wood fiber 1 may be oriented so that the fiber bundle is in the same direction as the transport direction.

  Examples of the wood fiber 1 supplied from the fiber supply unit D1 include hemp bast fibers such as kenaf and jute. Among these, hemp bast fibers are preferable because they contain a large amount of crystalline and high strength cellulose and have high strength as fibers. Hemp bast fibers can obtain long fibers from a hemp plant by, for example, a soaking process called letting and a physical defibrating process.

  The wood fiber 1 is preferably, for example, a long fiber having a length of 10 to 200 mm and a diameter of 100 μm or less. By using the long fiber, the shape retention of the fiber mat is improved by entwining the long fibers well. be able to. Moreover, the wood fiber 1 may be subjected to a pretreatment that is immersed in water to remove the adhesive component.

  Subsequently, the powder resin 2 is uniformly supplied and laminated on the wood fiber 1 from the resin supply part D2 disposed downstream of the fiber supply part D1, and the laminate 3 is formed.

  The powder resin 2 has thermosetting properties, and examples thereof include a powdered vinyl acetate resin, acrylic resin, epoxy resin, urethane resin, urea resin, melamine resin, phenol resin, and the like.

  And the quantity of the powder resin 2 supplied in a lamination process can be set in consideration of the intensity | strength, thickness, density, etc. of a wood fiber board.

  Moreover, it is preferable that liquid materials, such as water and alcohol, are contained in the wood fiber 1 in a lamination process. In this case, a liquid material can be mixed with the wood fiber 1 in advance, and the wood fiber 1 containing the liquid material can be supplied. Moreover, after supplying the wood fiber 1, the liquid material can be contained in the wood fiber 1 by spraying the liquid material from above.

  And the laminated body 3 formed at the lamination process is conveyed to the mixing part M in which the defibrating cylinder S was accommodated.

  In the defibrating process, the laminated body 3 formed in the laminating process is defibrated by the defibrating cylinder S to produce the fiber mat 4.

  On the surface of the defibrating cylinder S, needles (protrusions) for defibrating the wood fiber 1 are formed and provided with a plurality of small holes leading to the inside. The small holes on the surface of the defibrating cylinder S can be formed by, for example, punching metal or mesh. Further, suction means F is provided inside the defibrating cylinder S. Although the suction means F is not specifically limited, For example, well-known means, such as a fan, can be illustrated.

  In addition, a pressing roll R is disposed in front of the defibrating cylinder S. The laminate 3 transported by the transport conveyor C is pulled away in the rotation direction by the defibrating cylinder S that is rotated at a high speed while being pressed by the pressing roll R, and the separated wood fiber 1 and the powder resin 2 are mixed in the mixing unit M. Scatter. And the fiber mat 4 can be obtained by stacking the aggregate | assembly of the wood fiber 1 and the powder resin 2 which were mixed by this scattering, for example on the conveyance conveyor C downstream.

  In the laminated body 3 formed in the laminating process, the powder resin 2 is scattered around by centrifugal force during defibrating in the defibrating process. At this time, the powder resin 2 scattered by the defibration of the laminated body 3 is sucked and collected inside by the suction means F of the defibrating cylinder S and is reintroduced into the resin supply part D2 through the resupply channel W. For this reason, the loss of the powder resin 2 in the defibrating step is suppressed, and the fiber mat 4 can be obtained efficiently.

  Further, in the defibrating step, it is preferable to defibrate the laminate 3 by supplying dehumidified air into the mixing unit M that houses the defibrating cylinder S. As a result, the aggregate of the defibrated wood fiber 1 and the powder resin 2 is dried to reduce the amount of water, so that the powder resin 2 scattered at the time of defibration is covered with the cover part M1 of the mixing part M and the surrounding wall M2. The adhesion of the powder resin 2 to the inside is suppressed. Accordingly, since the scattered powder resin 2 is reliably sucked and collected by the suction means F (for example, a fan) and re-introduced, loss of the powder resin 2 is suppressed, and the fiber mat 4 can be obtained more efficiently. .

  Moreover, when the liquid material is contained in the wood fiber 1 formed in the lamination process, the scattering of the powder resin 2 at the time of the defibration of the laminate 3 in the defibration process can be adjusted appropriately.

  In the molding process, the fiber mat 4 manufactured in the defibrating process is hot-press molded to manufacture a plate-like wood fiberboard. As a method for pressing the fiber mat 4 in the molding step of the present invention, a batch type flat plate press, a continuous press, or the like can be adopted, but is not particularly limited. Moreover, the temperature, time, and pressure at the time of hot pressing can be appropriately set depending on the type of the powder resin 2 and the thickness and density of the wood fiber board.

  In the molding step, the fiber mat 4 can be pre-pressed (pre-pressed) as necessary before the fiber mat 4 is hot-press molded. In addition, the moisture content of the fiber mat 4 can be adjusted by drying the fiber mat 4 with a drying furnace or the like before hot pressing the fiber mat 4.

  According to the method for producing a wood fiber board of the present invention, the powder resin 2 scattered by defibration of the laminated body 3 is sucked and collected inside by the suction means F of the defibrating cylinder S and supplied through the resupply channel W. Part D2 is reintroduced. For this reason, since the powder resin 2 scattered in the defibrating process is reused and the loss is suppressed, the fiber mat 4 can be obtained efficiently.

  The manufacturing method of the wood fiber board of this invention is not limited to the above embodiment. For example, the layered product in the layering step may contain humidity control materials such as diatomaceous earth, silica gel, activated carbon, zeolite, activated clay, and the like. Furthermore, the method for producing a wood fiber board of the present invention includes a step of attaching a decorative sheet or veneer having a desired coloring or pattern on the surface of the wood fiber board, if necessary, or a wood fiber board. A process of applying a desired paint on the surface of the film is also included.

DESCRIPTION OF SYMBOLS 1 Wood fiber 2 Powder resin 3 Laminated body 4 Fiber mat D2 Resin supply part S Defibration cylinder F Suction means

Claims (3)

The following steps,
A laminating step of forming a laminate by supplying a powder resin from a resin supply unit on a wood fiber,
A method for producing a wood fiber board, comprising: a defibrating step of defibrating the laminate with a defibrating cylinder to obtain a fiber mat; and a forming step of producing a wood fiber board by hot pressing the fiber mat. ,
The defibrating cylinder is provided with suction means inside, and has a plurality of small holes leading to the inside on the surface, and the powder resin scattered by defibrating the laminate is used as the defibrating cylinder. A method for producing a wood fiberboard, wherein the suction means collects the suction by the inside and re-injects the resin into the resin supply section.   The method for producing a wood fiber board according to claim 1, wherein dehumidified air is supplied in the defibrating step.   The method for producing a wood fiber board according to claim 1 or 2, wherein the wood fiber layer in the laminating step contains a liquid material.