WO2015118814A1

WO2015118814A1 - Method for producing wooden board

Info

Publication number: WO2015118814A1
Application number: PCT/JP2015/000239
Authority: WO
Inventors: 弘樹塩田
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2014-02-06
Filing date: 2015-01-20
Publication date: 2015-08-13
Also published as: JP2015147354A

Abstract

　A method for producing a wooden board includes a first step for continuously conveying a first matted load in which a granular adhesive is dispersed in plant fibers, a second step for continuously supplying the surface of the first matted load with adhesive chips for causing the adhesive to adhere to crushed wood chips or plant particles while conveying the first matted load, a third step for continuously layering a second matted load in which the granular adhesive is dispersed in plant fibers over the front surface side of the first matted load supplied with the adhesive chips while conveying the first matted load, and a fourth step for pressing together the rear surface side of the first matted load and the front surface side of the second matted load to create a wooden board by molding using heat and pressure.

Description

Wood board manufacturing method

The present invention relates to a method for manufacturing a wooden board.

Conventionally, wood boards containing wood chips such as wood chips and plant-derived plant particles have been used in a wide range of fields as building materials such as floor materials, wall materials and door materials for houses. A wood board is manufactured by adding a synthetic resin as a binder to wood chips or plant particles, followed by heating and pressing.

In order to use a wooden board as a building material, it is necessary to develop strength as an appropriate density. However, simply increasing the density may deteriorate properties suitable as a building material such as heat insulating properties and moisture absorption properties. In addition, the densification of the wooden board increases the weight and causes a problem that it is difficult to handle at the construction site.

Therefore, there has been proposed a method for producing a long-fiber composite board that is lightweight and easy to handle but has excellent physical properties such as strength and dimensional stability (see, for example, Patent Document 1). In the method for producing a long fiber composite board described in Patent Document 1, a particle layer composed of a large number of particles obtained by processing a lignocellulosic material in which an adhesive is dispersed, and a large number of ligno in which an adhesive is dispersed. A plurality of fiber layers composed of cellulose long fibers are combined and heated and pressed. For this reason, the obtained long fiber composite board has sufficient strength while being lightweight.

Japanese Published Patent No. 2000-246709

However, in the method for producing a long fiber composite board described in Patent Document 1, a particle layer and a fiber layer are individually formed, and a plurality of individually formed layer bodies are bonded and laminated. For this reason, the production of the long fiber composite board is a batch process, and it is difficult to increase the production efficiency.

The present invention has been made in view of the circumstances as described above, and a method for manufacturing a wooden board that can improve productivity when manufacturing a wooden board excellent in basic performance such as strength and dimensional stability. It is an issue to provide.

In order to solve the above-mentioned problems, a method for producing a wooden board according to the present invention includes a first step of continuously conveying a first mat-like load in which a granular adhesive is dispersed in plant fibers, and the first mat. A second step of continuously supplying an adhesive chip in which an adhesive is attached to a crushed piece of wood or a plant particle while conveying the first mat-shaped load on the surface of the load, and the adhesive chip; A second mat-like load in which granular adhesive is dispersed in plant fibers is continuously laminated on the surface side of the first mat-like load supplied with Including a third step, and a fourth step of sandwiching the back surface side of the first mat-shaped load and the front surface side of the second mat-shaped load, and heating and pressing to produce a wood board. It is a feature.

According to the method for manufacturing a wooden board of the present invention, productivity when manufacturing a wooden board excellent in basic performance such as strength and dimensional stability can be improved.

It is process sectional drawing which showed typically one Embodiment of the manufacturing method of the wooden board of this invention.

FIG. 1 is a process cross-sectional view schematically showing an embodiment of a method for producing a wooden board of the present invention.

The method for manufacturing the wooden board 1 includes a first step of continuously conveying the first mat-like load 4 and a second step of supplying the adhesive chip 7 to the surface of the first mat-like load 4. . In the second step, the adhesive chip 7 is continuously supplied while the first mat-like load 4 is being conveyed.

Further, the method for manufacturing the wooden board 1 includes a third step of laminating the second mat-shaped load 8 on the surface side of the first mat-shaped load 4 after the second step. Also in the third step, the second mat-shaped load 8 is continuously stacked while the first mat-shaped load 4 is conveyed.

Moreover, the manufacturing method of the wooden board 1 is such that the laminate obtained by the third step is sandwiched from the back side of the first mat-like load 4 and the front side of the second mat-like load 8 and is heated and pressed. A fourth step of forming the wood board 1 by molding is included.

The first step, the second step, the third step, and the fourth step will be described in detail below.
(1) 1st process The 1st mat-shaped load 4 conveyed continuously in the 1st process is made into a long thing by loading the mixture which disperse | distributed the granular adhesive agent 3a to the vegetable fiber 2a on the belt conveyor 10. Formed. The plant fiber 2a and the granular adhesive 3a are put into the feeder 9 and stirred to disperse the granular adhesive 3a in the vegetable fiber 2a, and continuously fed from the feeder 9 onto the belt conveyor 10, and on the belt conveyor 10. The long first mat-like load 4 is developed in layers.

The plant fiber 2a is not particularly limited as long as it is a plant fiber that is usually used for the wooden board 1, but considering basic performances such as strength, durability, and dimensional stability of the wooden board 1, hemp natural fibers and palm It is preferable that it is any 1 type or more of a fiber or an agricultural waste fiber. Examples of hemp-based natural fibers include fibers collected from basts of hemp plants such as kenaf, flax, ramie, cannabis, jute, hemp, and sisal, and stems or leaves of hemp plants such as Manila hemp and sisal. Examples are fibers collected from muscle. These hemp-based natural fibers are obtained by mechanically defibrating plant raw materials and have a tensile strength about 2 to 14 times higher than wood fibers such as coniferous fibers and hardwood fibers. Examples of the palm fiber include an oil palm fiber obtained from oil palm and a coconut fiber obtained from coco palm. Examples of agricultural waste fibers include fibers made from agricultural waste such as sugar cane, corn, bamboo, and rice. By using such a plant fiber 2a, the high tensile strength of the plant fiber 2a itself can be effectively utilized, and therefore, particularly excellent performance with respect to bending performance and length change due to temperature change or humidity change, etc. The wood board 1 is provided.

The average fiber length of the plant fiber 2a is not particularly limited, but considering basic performance such as strength, durability and dimensional stability of the wooden board 1, it is 5 mm or more and 100 mm or less, preferably 10 mm or more and 70 mm or less, more preferably. Is 30 mm or more and 60 mm or less. By using the plant fibers 2a having an average fiber length within the above range, there are many entanglements of the plant fibers 2a inside the wood board 1 after the heat and pressure molding, and moreover, per plant fiber 2a. The adhesion part of granular adhesive agent 3a can be increased. Furthermore, since the joint part between plant fibers 2a can be reduced, the high tensile strength of plant fiber 2a itself can be utilized more effectively. For this reason, the wood board 1 which has more excellent performance with respect to strength, surface hardness, length change due to temperature change and humidity change, etc. is realized while being low density.

The average fiber diameter of the plant fiber 2a is not particularly limited, but considering basic performance such as strength, durability and dimensional stability of the wooden board 1, it is 70 μm or more and 400 μm or less, preferably 100 μm or more and 350 μm or less, more preferably. Is exemplified by 150 μm or more and 300 μm or less. By using the plant fiber 2a having an average fiber diameter within the above range, an appropriate gap is created between the plant fibers 2a, and the granular adhesive 3a can be uniformly dispersed in the gap. Moreover, many entanglements of the plant fibers 2a exist due to the rigidity of the plant fibers 2a, and the wood board 1 having sufficient strength can be obtained.

The granular adhesive 3a dispersed in the plant fiber 2a is not particularly limited as long as it is an adhesive that is usually used for the wooden board 1. Examples thereof include those in which a thermosetting resin such as a phenol resin, a resorcinol resin, a urea resin, a melamine resin, an epoxy resin, a urethane resin, a furfural resin, and an isocyanate resin is used alone or in combination of two or more. A sizing agent or the like can be added to the granular adhesive 3a as necessary.

The mixing ratio of the granular adhesive 3a in the first mat-shaped load 4 is not particularly limited, but is preferably in the range of 10% by mass to 20% by mass as the solid content after curing. If the blending ratio of the granular adhesive 3a is within the above range, the plant fibers 2a are sufficiently bonded to each other, and the strength of the obtained wood board 1 is improved.
(2) Second Step In the second step, the adhesive chip 7 to be supplied to the surface of the first mat-shaped load 4 is obtained by adhering the adhesive 6 to the crushed wood pieces or the plant particles 5.

The crushed wood pieces are not particularly limited as long as they are crushed wood pieces used for the wood board 1, but considering basic performance such as strength, durability and dimensional stability of the wood board 1, the wood pieces are crushed. The resulting strip or fiber is preferred. Since the fine pieces or fibers obtained by pulverizing the wood pieces are obtained by pulverizing the end materials and the like at the time of lumbering, reduction of the manufacturing cost of the wood board 1 is expected.

Also, as the crushed wood pieces, fine pieces crushed into a wood powder or coarse pieces in the form of wood pieces can be used.

Examples of such crushed wood pieces include those mainly made of thinned wood and building demolition materials. Examples of the thinned wood include conifers such as pine, cedar and cypress, and broad-leaved trees such as lawan, capol and poplar.

The plant particle is not particularly limited as long as it is a plant particle that is usually used for the wooden board 1, but considering basic performance such as strength, durability, and dimensional stability of the wooden board 1, it is a hemp plant particle. It is preferable. The particles of the hemp plant have the same characteristics as the hemp natural fiber used for the first mat-like load 4, and become a material of the wood board 1 excellent in basic performance such as strength and dimensional stability. .

Examples of the size of the crushed wood pieces or plant particles 5 include a thickness of 0.1 mm to 5 mm, a length of 1 mm to 50 mm, and a width of 0.5 mm to 10 mm. If it exists in said range, the adhesion | attachment of crushed wood pieces or the plant particle 5 will become enough, and the intensity | strength of the obtained wooden board 1 will become favorable.

Equipment and equipment that can be used to produce the crushed wood pieces or plant particles 5 are not particularly limited. For example, a hammer mill, a drum flaker, a ring flaker, a disc refiner, or the like can be used.

The adhesive 6 attached to the crushed wood pieces or the plant particles 5 is not particularly limited. It can be appropriately selected and employed from thermosetting resin adhesives usually used in the production of the wood board 1. For example, an isocyanate resin adhesive composed of MDI (diphenylmethane diisocyanate), TDI (tolylene diisocyanate), MDI prepolymer, TDI prepolymer and the like is exemplified. Moreover, a urea resin adhesive, a melamine resin adhesive, and a urea / melamine cocondensation resin adhesive are exemplified. Furthermore, a phenol resin adhesive, a resorcinol resin adhesive, an epoxy resin adhesive, a urethane resin adhesive, and a furfural resin adhesive are exemplified. These adhesives 6 can be used alone or in combination of two or more. Further, the adhesive 6 may be in the form of powder or liquid. Furthermore, the selection of the adhesive 6 can also take into consideration the water resistance of the wooden board 1 and the amount of formaldehyde released that causes sick house syndrome. The isocyanate resin adhesive is a highly safe adhesive 6 because it does not use formaldehyde as a raw material. A sizing agent or the like can be added to the adhesive 6 as necessary.

When adhering the adhesive 6 to the crushed wood pieces or the plant particles 5, the crushed wood pieces or the plant particles 5 are supplied onto the belt conveyor 11 and conveyed on the belt conveyor 11, while the adhesive 6 is supplied from the feeder 12. The adhesive 6 can be attached to the crushed wood pieces or the plant particles 5. As the feeder 12, it is possible to use a quantitative feeder such as a glue blender or a conventional mixing equipment such as a ribbon blender, a high-speed mixer, or a tumbler. In addition, the adhesive 6 can be supplied to the crushed wood pieces or the plant particles 5 by a predetermined amount by a rotary feeder, a screw feeder or the like provided in the production line. By doing so, it is possible to uniformly mix the crushed wood pieces or plant particles 5 and the adhesive 6.

The amount of the adhesive 6 to be attached to the crushed wood pieces or the plant particles 5 is not particularly limited. For example, 15 mass% or less is illustrated as solid content after hardening with respect to a crushed wood piece or the plant particle 5.

When the adhesive chip 7 is continuously supplied to the surface of the first mat-shaped load 4 after the first step, the adhesive chip 7 is put into the feeder 13 and the stirred adhesive chip 7 is supplied. It can be continuously supplied from the machine 13 to the surface side of the first mat-like load 4. Thus, the supply of the adhesive chip 7 is continuously performed on the first mat-shaped load 4 conveyed by the belt conveyor 10.
(3) Third Step In the third step, the second mat-shaped load 8 is continuously laminated on the surface side of the first mat-shaped load 4 after the second step as described above. Similarly to the first mat-shaped load 4, the second mat-shaped load 8 is formed by laminating a mixture in which the granular adhesive 3 b is dispersed in the vegetable fiber 2 b on the belt conveyor 10 to form a long length. is there. The plant fiber 2b and the granular adhesive 3b are put into the feeder 14 and stirred to disperse the granular adhesive 3b in the vegetable fiber 2b, and this mixture is continuously supplied from the feeder 14 to the surface side of the first mat-like load 4. To supply. By continuously supplying in this way, the second mat-like load 8 is continuously stacked on the first mat-like load 4 conveyed by the belt conveyor 10.

The plant fibers 2b and the granular adhesive 3b forming the second mat-shaped load 8 may be the same as or different from the plant fibers 2a and the granular adhesive 3a forming the first mat-shaped load 4. It may be.
(4) Fourth Step In the fourth step, the laminate obtained by the third step is heated and pressed in the press 17. Specifically, the lower press 15 is applied from the back surface side of the first mat-shaped load 4, and the upper press 16 is applied from the front surface side of the second mat-shaped load 4, so 2 The surface side of the mat-like load 8 is sandwiched. And the wood board 1 is produced by heat-press molding with the press machine 17.

When hot press molding is performed by the press machine 17, for example, a press machine composed of a lower press 15 and an upper press 16 that are heated hot plates, or a laminate while applying pressure to a gap between a pair of heated steel belts. A continuous press device or the like for conveyance can be used. The heating and pressure molding conditions of the wood board 1 are not particularly limited as long as the granular adhesives 3a and 3b used and the adhesive 6 attached to the adhesive chip 7 are cured. For example, the molding temperature is in the range of 120 ° C. to 190 ° C., and the molding pressure is in the range of 1 MPa to 4 MPa. The pressurization time can be appropriately set in consideration of the thickness and density of the wood board 1 obtained after the heat press molding, the heating temperature at the time of molding, and the like. The thickness of the wood board 1 can be set within a range of 1 mm to 20 mm, for example, and is preferably 2 mm or more in consideration of basic performance such as strength, durability, and dimensional stability of the wood board 1. . The density of the wood board 1 can be set in the range of 600 kg / m ³ to 900 kg / m ³ , more preferably in the range of 700 kg / m ³ to 850 kg / m ³ . If the density of the wooden board 1 is within the above range, the wooden board 1 is superior in basic performance such as strength, durability, and dimensional stability, and is advantageous in terms of cost.

Through such a fourth step, the first plant fiber layer 18 is formed on the back surface, the second plant fiber layer 20 is formed on the surface, between the first plant fiber layer 18 and the second plant fiber layer 20, The wood board 1 in which the chip layer 19 is formed as a core layer is obtained.

In the manufacturing method of the woody board 1 as described above, the formation of the first plant fiber layer 18, the chip layer 19 and the second plant fiber layer 20 is continuous, and is realized at one time by heat-pressure molding. The wood board 1 in which the

layers

18, 19, and 20 are integrated is obtained. Therefore, the wooden board 1 excellent in basic performance such as strength, durability, and dimensional stability can be continuously manufactured, and the productivity of the wooden board 1 can be improved.

The wooden board 1 can be widely applied to building members such as flooring materials, wall materials and ceiling materials, door members, construction materials such as baseboards, surrounding edges, and furniture materials.

DESCRIPTION OF SYMBOLS 1 Wood board 2a, 2b Plant fiber 3a, 3b Granular adhesive 4 1st mat-like load 5 Wood piece ground product or plant particle 6 Adhesive 7 Adhesive chip 8 2nd mat-like load

Potential for industrial use

According to the method for manufacturing a wooden board of the present invention, the productivity when manufacturing a wooden board excellent in basic performance such as strength and dimensional stability can be improved.

Claims

A first step of continuously conveying a first mat-like load in which a granular adhesive is dispersed in plant fibers;
A second step of continuously supplying an adhesive chip in which an adhesive is adhered to a crushed wood piece or a plant particle while conveying the first mat-shaped load to the surface of the first mat-shaped load;
A second mat-like load in which a granular adhesive is dispersed in plant fibers is continuously conveyed to the surface side of the first mat-like load supplied with the adhesive chip while the first mat-like load is conveyed. A third step of automatically stacking,
A fourth step of producing a wood board by sandwiching a back side of the first mat-like load and a front side of the second mat-like load and forming by heating and pressing. Production method.
The method for producing a wooden board according to claim 1, wherein the plant fiber is one or more of hemp-based natural fiber, palm fiber, or agricultural waste fiber.
The method for producing a wood board according to claim 1 or 2, wherein the crushed wood pieces are fine pieces or fibers obtained by pulverizing wood pieces.
The method for producing a wooden board according to any one of claims 1 to 3, wherein the plant particles are particles of a hemp plant.