WO2023176286A1 - Method for producing fiber board and compressed material for production of fiber board - Google Patents

Abstract

The present disclosure addresses the problem of providing a method for producing a fiber board, capable of increasing the strength of the fiber board both when using a flat die molding machine or a ring die molding machine to produce a compressed material. The method for producing a fiber board according to the present disclosure involves a compression step, a steaming and fibrillating step, a forming step, and a thermal pressing step. In the compression step, a mixture of wax and a pulverized material made from a plant of the family Palmae is compressed to obtain a compressed material (1). In the steaming and fibrillating step, the compressed material (1) is steamed and fibrillated to obtain ligneous fibers. In the forming step, an adhesive is added to the ligneous fibers, and the ligneous fibers are shaped to obtain a mat-shaped product. In the thermal pressing step, the mat-shaped product is pressed while being heated.

Description

Method for manufacturing fiberboard and compressed material for manufacturing fiberboard

The present disclosure generally relates to a method for manufacturing a fiberboard and a compressed material for manufacturing a fiberboard, and more particularly relates to a method for manufacturing a fiberboard using a palm plant and a compressed material for manufacturing a fiberboard.

Patent Document 1 discloses a pellet manufacturing device that crushes and compresses biomass material to form pellets. This pellet manufacturing device includes a box, a die, and a push roller.

Here, the box has an internal space, and an input port for inputting the biomass material is formed at the top, and a discharge port for discharging the manufactured pellets is formed at the bottom. Further, the die is provided so as to partition the internal space into upper and lower parts, and is formed so that a hole group consisting of a large number of through holes passing through the die vertically extends in a predetermined direction. In addition, the push roller is disposed above the die, and by rolling over the hole group, crushes the biomass material input from the input port between it and the die, and pushes it into each through hole. It is compressed into pellets while passing through it.

However, the pellet manufacturing apparatus of Patent Document 1 has a problem in that the wood fibers contained in the biomass material are easily broken and cut when manufacturing pellets. Although the pellet manufacturing apparatus of Patent Document 1 is an example of a so-called flat die type molding machine, the above problem also applies to a so-called ring die type molding machine. Therefore, many relatively short wood fibers tend to remain in the obtained pellets. Therefore, when attempting to manufacture a fiber board using such pellets, it is difficult to improve the strength of the fiber board because the length of the wood fibers is relatively short.

Japanese Patent Application Publication No. 2018-144341

The purpose of the present disclosure is to provide a method for manufacturing a fiber board that can improve the strength of the fiber board even when a compressed product is manufactured using either a flat die molding machine or a ring die molding machine, and The purpose of the present invention is to provide a compressed material for board manufacturing.

A method for manufacturing a fiber board according to one aspect of the present disclosure includes a compression step of compressing a mixture of a crushed product of a palm plant and wax to obtain a compressed product, and a step of steaming and defibrating the compressed product to obtain wood fibers. a steam defibration step to obtain the wood fibers, a forming step to obtain a mat-like molded product by adding an adhesive to the wood fibers and molding the wood fibers, and a hot-pressing step to compress the mat-like molded product while heating. include.

A compressed product for manufacturing fiberboard according to one aspect of the present disclosure is a compressed product in which a mixture of a crushed product of a palm plant and a wax is compressed.

FIG. 1 is a schematic perspective view showing a compressed material (compressed material) for fiberboard production according to the present embodiment, partially seen through. FIG. 2 is a schematic perspective view showing a molding machine used in the fiber board manufacturing method according to the present embodiment.

1. Overview As mentioned above, the pellet manufacturing apparatus of Patent Document 1 has the problem that the wood fibers contained in the biomass material easily break when producing pellets, causing the wood fibers to be cut or cracked. was there. The inventors believe that the cause is as follows. In other words, the biomass material that is coarsely crushed to be fed into the pellet manufacturing device generally has an elongated shape with a long length in the fiber direction, so the biomass material fed into the pellet manufacturing device of Patent Document 1 is The wood fibers contained in the biomass material are also likely to be arranged horizontally on the die. Therefore, the wood fibers are pushed into the through holes in a state where the direction in which the hole group consisting of a large number of through holes extends and the fiber direction of the wood fibers are not aligned, making the wood fibers easy to break. In addition, because the direction in which the holes extend and the direction in which the pushing roller rolls over the holes are perpendicular, it is difficult for the biomass material to enter the through holes, and a force in a direction different from the fiber direction is applied to the wood fibers. becomes easy to break. The present inventors think as described above.

The present inventors conducted extensive research in order to improve the strength of the fiber board by devising the material of the fiber board, rather than improving the pellet manufacturing device itself. As a result, we have developed the following method for manufacturing fiberboard. That is, the method for manufacturing a fiber board according to the present embodiment includes a compression process, a steaming defibration process, a forming process, and a hot pressing process.

In the compression step, for example, a molding machine 3 as shown in FIG. 2 is used to compress a mixture of a crushed product of a palm plant and wax (not shown in FIG. 2) to obtain a compressed product 1. In this way, the addition of wax to the crushed product of the coconut family improves the slippage between the wood fibers 2 contained in the crushed product and the slippage between the wood fibers 2 and the surface of the molding machine 3. . Therefore, even if the compressed material 1 is manufactured using either the flat die molding machine 3 or the ring die molding machine 3, the wood fibers 2 are less likely to break. Therefore, many relatively long wood fibers 2 and wood fibers 2 with few cracks remain in the compressed material 1.

In the steaming and defibrating step after the compression step, the compressed material 1 is steamed and defibrated to obtain the wood fibers 2. In the forming step after the steaming and fibrillation step, an adhesive is added to the wood fibers 2 and molded to obtain a mat-like molded product. In the hot pressing step after the forming step, the mat-shaped molded product is pressed while being heated. This results in a fiber board.

The length of the wood fibers 2 may be somewhat shortened through the steaming and fibrillation process, the forming process, and the heat-pressing process. However, since many relatively long wood fibers 2 remain in the compressed material 1 used for manufacturing fiberboard, even after these steps, the relatively long wood fibers 2 remain as fibers compared to when no wax is added. It will also be included on the board.

Therefore, the strength of the fiber board can be improved.

2. Details The fiber board according to this embodiment includes an insulation board, medium density fiberboard (MDF), and hardboard. Preferably the fiberboard is medium density fiberboard.

The method for manufacturing fiber board includes a compression process, a steaming defibration process, a forming process, and a hot pressing process. Below, these steps will be explained in order.

<Compression process>
In the compression step, a mixture of a crushed product of a palm plant and wax is compressed to obtain a compressed product 1 for manufacturing fiberboard (hereinafter sometimes simply referred to as "compressed product 1"). Hereinafter, the pulverized product of palm family plants, wax, molding machine 3, and compressed product 1 will be explained in order.

≪Crushed palmaceous plants≫
The type of palm family plant is not particularly limited, but includes, for example, oil palm, sorghum palm, coconut palm, date palm, sago palm, acai, palm, and the like. Usable parts of palm plants include, but are not particularly limited to, stem parts, leaves, fruit parts, cluster parts, and seed parts.

In particular, oil palm is a type of palm tree that has been planted in Malaysia, Indonesia, Thailand, Colombia, etc. to obtain edible oil, etc. Oil palm trunks (OPT) are treated as an unused resource because they lack the strength to be used as a building material. In addition, oil palm tree trunks contain sugar and are easily rotten, so currently they are left alone and disposed of by rotting, but this is an environmental concern as greenhouse gases are emitted when they rot.

A crushed product of a palm plant is obtained as a collection of chips by crushing a palm plant with a chipper. Chips obtained by crushing palm plants generally have an elongated shape with a long length in the fiber direction. The chip preferably has a length of 0.6 mm or more and 50.0 mm or less, and an outer diameter of 0.10 mm or more and 2.00 mm or less. A chip that meets the above length and outer diameter will be referred to as a "suitable chip" hereinafter, and a chip that does not meet the above length and outer diameter may be referred to as an "unsuitable chip" hereinafter. In addition, the length and outer diameter of the chips contained in the crushed material of the palm family plant can be determined by taking a photograph of a predetermined amount of the crushed material of the palm family plant or observing it with a magnifying glass. Obtained by measuring .

Here, if the length of the chip is 0.6 mm or more, it is possible to suppress a decrease in the strength of the fiber board. This also applies when the outer diameter of the chip is 0.10 mm or more.

Also, by having the length of the chip at 50.0 mm or less, it is possible to suppress a decrease in the surface smoothness of the fiber board. This also applies when the outer diameter of the chip is 2.00 mm or less.

The content of the suitable chips is preferably 70% by mass or more, more preferably 80% by mass or more, based on the total amount of the crushed coconut material (the total amount of suitable chips and non-preferred chips). When the content of suitable chips is 70% by mass or more, it is possible not only to suppress a decrease in the strength of the fiber board, but also to easily manufacture a fiber board with more stable quality. Note that the upper limit of the content of suitable chips is not particularly limited, but is, for example, 100% by mass or less.

Here, the parenchymal tissue of palm trees can be a factor in variations in the quality of fiber boards. Therefore, it is preferable that the crushed product of the coconut family plant is obtained by crushing the palm family plant and then classifying it to reduce the amount of parenchyma. In other words, the crushed product of palm trees before classification includes a crushed product mainly composed of parenchymal tissue and a crushed product mainly composed of vascular tissue, but by classification, relatively small parenchymal cells It is preferable to reduce the amount of pulverized material whose main component is tissue. In this manner, the amount of the crushed material containing parenchymal tissue as a main component is reduced in the crushed material after classification compared to the crushed material before classification. Thereby, the ratio of vascular tissue contained in the compressed material 1 becomes high, and the fiber board can be stably manufactured. Note that the parenchyma cell tissue is a tissue composed of parenchyma cells. Parenchymal tissue includes anabolic tissue, secretory tissue, storage tissue, etc., and has physiological functions such as synthesis, decomposition, and storage.

Methods for reducing the amount of unsuitable chips (parenchyma and large chips) by classification are not particularly limited, but include, for example, using two sieves with different mesh sizes. That is, if the pulverized material passes through a sieve with a large opening but does not pass through a sieve with a small opening, the amount of unsuitable chips is likely to be reduced. Here, examples of the sieve with large openings include sieves of 4.7 mesh (opening 4.00 mm) to 16 mesh (opening 1.00 mm). On the other hand, examples of sieves with small openings include sieves of 149 mesh (opening 100 μm) to 235 mesh (opening 63 μm).

It is preferable that the crushed product of the palm plant is dried. The water content of the crushed product of the palm plant is preferably 25% by mass or less, more preferably 20% by mass or less. The shape retention of the compressed material 1 is improved because the water content of the crushed product of the palm family plant is 25% by mass or less. Moreover, the progress of decay of the wood fibers 2 contained in the compressed material 1 can be prevented, and the storage property of the compressed material 1 is improved. In addition, the moisture content of the crushed product of the palm family plant can be determined by the total drying method.

In this way, in this embodiment, palm plants can be used as plants for manufacturing fiberboard, so resources can be used effectively.

≪Wax≫
The wax improves the slippage between the wood fibers 2 contained in the crushed product of the coconut family, and the slippage between the wood fibers 2 and the surface of the molding machine 3 during the compression process. In other words, the wax can suppress bending of the wood fibers 2. Furthermore, water resistance can also be imparted to the compressed material 1.

Waxes include, but are not particularly limited to, natural waxes, synthetic waxes, and the like. The wax may be liquid (for example, an emulsion) or solid at room temperature. When the wax is liquid, at least a portion of the wax permeates into the wood fibers 2, and due to the synergistic effect with water, the wood fibers 2 can be made flexible and less likely to break. On the other hand, when the wax is solid, for example, when using the molding machine 3 shown in FIG. Since the wood fibers 2 are easily interposed between the wood fibers 2 and the compression roller 5, the wood fibers 2 can be made less likely to break due to the buffering effect.

Natural waxes include, but are not particularly limited to, paraffin wax, beeswax, carnauba wax, and the like.

Synthetic waxes include, but are not particularly limited to, polyethylene wax, ethylene vinyl acetate wax, and the like.

With respect to 100% by mass of the total mass (absolutely dry mass) of the crushed product of the palm family plant, the addition rate (external multiplication) of wax is preferably more than 0.05% by mass and 5% by mass or less, more preferably 0.1% by mass. It is not less than 1% by mass and not more than 1% by mass. When the wax addition rate is more than 0.05% by mass, bending of the wood fibers 2 can be further suppressed, and the water resistance of the compressed product 1 can also be further improved. When the wax addition rate is 5% by mass or less, deterioration in the shape retention of the compressed product 1 can be suppressed.

≪Molding machine≫
For example, a molding machine 3 (pelletizer) can be used to obtain the compressed product 1 from the mixture of ground coconut and wax. The molding machine 3 is not particularly limited, but includes, for example, a flat die molding machine and a ring die molding machine. Although a tableting method can also be used to obtain the compressed product 1, the pelletizer method has the advantage of higher production efficiency than the tableting method.

Figure 2 shows an example of the molding machine 3 (flat die molding machine). The molding machine 3 includes a die 4 and at least one (two in this embodiment) compression rollers 5. The molding machine 3 may further include a cutter (not shown).

The die 4 has an annular shape. The die 4 has a first surface 41, a second surface 42, and at least one (in this embodiment, plural) through holes 40.

The first surface 41 is a surface to which a mixture of crushed coconut and wax is supplied.

The second surface 42 is a surface opposite to the first surface 41. The second surface 42 is a surface from which the compressed material 1 is extruded. In this way, the compressed material 1 is obtained from the second surface 42.

The through hole 40 penetrates from the first surface 41 to the second surface 42. The through hole 40 is a cylindrical space extending from the first surface 41 to the second surface 42 . The through-hole 40 is a space in which a mixture of crushed coconut and wax is pushed and compressed to form a compressed product 1. Therefore, the inner diameter of the through hole 40 is approximately equal to the outer diameter of the compressed material 1.

The compression roller 5 rolls on the first surface 41 of the die 4. As a result, the crushed coconut material and wax supplied to the first surface 41 are forced into the through holes 40 . The pressure at this time is not particularly limited, but is, for example, 0.5 MPa or more and 1.0 MPa or less.

Here, the rolling direction of the compression roller 5 (direction parallel to the first surface 41) is not the same direction as the direction of penetration of the through hole 40. In this embodiment, the rolling direction of the compression roller 5 is perpendicular to the direction in which the through holes 40 penetrate.

The compression roller 5 includes a first compression roller 51 and a second compression roller 52. The first compression roller 51 and the second compression roller 52 have a cylindrical shape with the same dimensions. The first compression roller 51 and the second compression roller 52 are rotatably attached to both ends of the connecting shaft 53. The connection shaft 53 is a shaft extending along the rotation axis C2. The first compression roller 51 and the second compression roller 52 are rotatable in opposite directions about the rotation axis C2 (see arrows in FIG. 2). A main shaft 50 is fixed perpendicularly to the connecting shaft 53 at the center of the connecting shaft 53 . The main shaft 50 is a shaft extending along the rotation axis C1. The main shaft 50 is rotatable around the rotation axis C1 (see arrow in FIG. 2). As the main shaft 50 rotates in this way, the compression roller 5 (the first compression roller 51 and the second compression roller 52) rolls on the first surface 41 of the die 4.

Although not shown in FIG. 2, the cutter is a member for cutting the compressed material 1 extruded from the second surface 42 into lengths of several cm that are easy to handle.

≪Compressed material≫
As shown in FIG. 1, the compressed material 1 is, for example, in the form of a pellet. Specifically, the compressed material 1 has a cylindrical shape extending in one direction. One direction originates from the penetrating direction of the through hole 40. Due to the action of the wax during the compression process, the wood fibers 2 become difficult to break, so many relatively long wood fibers 2 and wood fibers 2 with few cracks remain in the obtained compressed product 1. Furthermore, since the compressed product 1 contains wax (not shown in FIG. 1), the water resistance of the compressed product 1 is improved.

The specific gravity of the compressed product 1 is preferably 0.35 or more and 1.50 or less, more preferably 0.40 or more and 1.50 or less. This improves the mechanical durability of the compressed material 1, making it difficult for the compressed material 1 to crumble or crack during transportation.

The moisture content of the compressed product 1 is preferably 25% by mass or less, more preferably 20% by mass or less. When the moisture content of the compressed product 1 is 25% by mass or less, the shape retention of the compressed product 1 is improved. Moreover, the progress of decay of the wood fibers 2 contained in the compressed material 1 can be prevented, and the storage property of the compressed material 1 is improved. In addition, the moisture content of the compressed material 1 can be determined by a total drying method.

<Steam defibration process>
The steaming and fibrillation step is a step in which the compressed material 1 is made into fibers. That is, in the steaming and defibrating step, the compressed material 1 is steamed and defibrated to obtain the wood fibers 2. Specifically, saturated steam is introduced into the compressed material 1 to soften the lignin in the compressed material 1, and the compressed material 1 is dissociated into fibers or fiber bundles to obtain the wood fibers 2. In the steaming defibration step, a known steaming defibration device can be used.

Here, the temperature during steaming is not particularly limited, but is, for example, 150°C or higher and 200°C or lower. The relative humidity during steaming is not particularly limited, but is, for example, 90% RH or higher. The time for the steaming and defibrating step is not particularly limited, and is, for example, 1 minute or more and 15 minutes or less.

<Forming process>
In the forming process, a mat-like molded product is obtained by adding an adhesive to the wood fibers 2 and molding them. Forming is preferably carried out by a dry method. In dry forming, a known gravity former or suction former can be used. Note that a water repellent may be added in addition to the adhesive.

Here, the adhesive is not particularly limited, but examples thereof include diphenylmethane diisocyanate (MDI), urea resin, urea-melamine cocondensation resin, and phenol resin.

The blending amount of the adhesive is not particularly limited to the total mass of the wood fibers 2 and the adhesive, but is, for example, 1% by mass or more and 10% by mass or less.

<Heat pressure process>
In the hot pressing process, the mat-shaped molded product is pressed while being heated. In the hot press step, a known hot press can be used. A distance bar (thickness gauge) may be installed between the hot plates of the hot press. The distance bar allows the thickness of the fiberboard to be constant.

The heating temperature is not particularly limited, but is, for example, 140°C or higher and 230°C or lower. The pressure at the time of clamping is not particularly limited, but is, for example, 0.5 MPa or more and 10 MPa or less. The heat-pressing time is not particularly limited, but is, for example, 10 seconds or more and 3 minutes or less.

In the above manner, the fiber board according to this embodiment is obtained. The thickness of the fiber board is not particularly limited, but is, for example, 1 mm or more and 20 mm or less.

<Others>
The method for manufacturing fiberboard may further include a humidity conditioning step. In the humidity conditioning process, the fiber board after the heat-pressing process is left in the atmosphere for a certain period of time, or processed in a humidity conditioning device. Since the moisture content of the fiberboard immediately after the hot pressing process is very low, it is preferable to increase the humidity until the moisture content approaches the moisture content that is in equilibrium with the conditions of use.

<Effect>
As described above, the method for manufacturing a fiber board according to the present embodiment includes a compression process, a steaming defibration process, a forming process, and a hot pressing process.

In the compression step, a mixture of crushed coconut and wax is compressed to obtain a compressed product 1. In this way, the addition of wax to the crushed product of the coconut family improves the slippage between the wood fibers 2 contained in the crushed product and the slippage between the wood fibers 2 and the surface of the molding machine 3. . Therefore, in the molding machine 3, even if the rolling direction of the compression roller 5 and the penetrating direction of the through hole 40 are not the same direction, the wood fiber 2 becomes difficult to break. In other words, the wood fibers 2 are less likely to break even when the compressed material 1 is manufactured using either a flat die molding machine 3 or a ring die molding machine 3. Therefore, many relatively long wood fibers 2 and wood fibers 2 with few cracks remain in the compressed material 1. Furthermore, wax is present in the compressed material 1. This wax imparts water resistance (water repellency) to the compressed product 1. Thereby, even if the compressed product 1 is splashed with water during transportation and storage, the shape of the compressed product 1 is easily maintained.

In the steaming and defibrating step after the compression step, the compressed material 1 is steamed and defibrated to obtain the wood fibers 2. In the forming step after the steaming and fibrillation step, an adhesive is added to the wood fibers 2 and molded to obtain a mat-like molded product. In the hot pressing step after the forming step, the mat-shaped molded product is pressed while being heated. This results in a fiber board.

The length of the wood fibers 2 may be somewhat shortened through the steaming and fibrillation process, the forming process, and the heat-pressing process. However, since many relatively long wood fibers 2 remain in the compressed material 1 used for manufacturing fiberboard, even after these steps, relatively long wood fibers 2 remain in the fiberboard compared to when no wax is added. will also be included.

Therefore, the strength of the fiber board can be improved.

3. Aspects As is clear from the above embodiments, the present disclosure includes the following aspects. In the following, reference numerals are given in parentheses only to clearly indicate the correspondence with the embodiments.

The first aspect is a method for manufacturing a fiber board, which includes a compression step, a steaming defibration step, a forming step, and a hot pressing step. In the compression step, a mixture of a crushed product of a palm plant and wax is compressed to obtain a compressed product (1). In the steaming and defibrating step, the compressed material (1) is steamed and defibrated to obtain wood fibers (2). In the forming step, an adhesive is added to the wood fibers (2) and molded to obtain a mat-like molded product. In the hot pressing step, the mat-shaped molded product is pressed while being heated.

According to this aspect, since the wax is added to the crushed product of the palm plant, even when the compressed product (1) is manufactured using either a flat die type molding machine or a ring die type molding machine, , the wood fibers (2) are less likely to break, and many relatively long wood fibers (2) remain, improving the strength of the fiber board.

The second aspect is a method for manufacturing fiberboard based on the first aspect. In a second aspect, the pulverized product is obtained by pulverizing the palm-family plant and then classifying it to reduce the amount of parenchyma.

According to this aspect, parenchymal tissue is less likely to be included in the compressed material (1), and the fiber board can be stably manufactured.

The third aspect is a method for manufacturing fiberboard based on the first or second aspect. In a third aspect, the pulverized material contains chips having a length of 0.6 mm or more and 50.0 mm or less and an outer diameter of 0.10 mm or more and 2.00 mm or less, based on the total mass of the pulverized material, at least 70% by mass. contains.

According to this aspect, a decrease in the strength of the fiber board can be suppressed, and a decrease in the surface smoothness of the fiber board can also be suppressed.

A fourth aspect is a method for manufacturing a fiber board based on any one of the first to third aspects. In a fourth aspect, a first surface (41), a second surface (42) on the opposite side of the first surface (41), and a penetration from the first surface (41) to the second surface (42) are provided. A molding machine (3) is used, which includes a die (4) having a through hole (40), and a compression roller (5) rolling on the first surface (41). The mixture is supplied to the first surface (41), the mixture is pushed into the through hole (40) by the compression roller (5) and compressed to form the compressed product (1), and the compressed product (1) is obtained by extruding it from the second surface (42).

According to this aspect, even if the penetration direction of the through hole (40) and the rolling direction of the compression roller (5) are not the same direction (for example, even if they are perpendicular), the wax remains in the crushed product of the palm plant. By adding it, the wood fiber (2) becomes difficult to break when producing the compressed material (1).

The fifth aspect is a compressed product (1) for producing a fiber board, which is a compressed product (1) in which a mixture of a crushed product of a palm plant and a wax is compressed.

According to this aspect, since many relatively long wood fibers (2) remain, the strength of the fiber board can be improved. Furthermore, since the wax imparts water resistance (water repellency) to the compressed product (1), the shape of the compressed product (1) is maintained even if the compressed product (1) is exposed to water during transportation or storage. It becomes easier.

Hereinafter, the present disclosure will be specifically explained using examples. However, the present disclosure is not limited to the following examples.

1. Samples As shown in Table 1 below, for Examples 1 to 7 and Comparative Examples, compressed materials for fiber board production were obtained, and then fiber boards were manufactured using these compressed materials. In addition, "chip average length" in Table 1 is the average value of the length of the chips contained in the crushed product of the palm family plant. Moreover, the "chip average diameter" in Table 1 is the average value of the outer diameter of the chips contained in the crushed product of the palm plant.

Hereinafter, Examples 1 to 7 and Comparative Examples will be explained in detail.

(1) Example 1
The trunk part of an oil palm (OPT) was used as a raw material (coconut family plant) for the fiber board, and it was put into a chipper to obtain a pulverized angular product with a size of 30 mm or more and 40 mm or less. After removing foreign matter from the angular pulverized material using a foreign matter remover, it is fed into a wet mill and pulverized, and then dried to a predetermined moisture content using a rotary kiln to produce a dry pulverized material. Obtained.

Next, for the dried pulverized product, an 8.6 mesh (opening 2.00 mm) sieve and a 200 mesh (opening 75 μm) sieve were used. Then, a pulverized product that passed through an 8.6 mesh sieve but did not pass through a 200 mesh sieve was obtained from the dry pulverized product. This pulverized material has reduced parenchymal tissue. The average chip length, average chip diameter, and preferred chip content of this pulverized product are as shown in Table 1. Note that the average chip length and average chip diameter were obtained by measuring the length and outer diameter of the chips contained in each crushed product using a magnifying glass for a predetermined amount of the crushed products, and calculating the arithmetic mean. In addition, the suitable chip content is determined by measuring the length and outer diameter of chips contained in a predetermined amount of crushed material using a magnifying glass. It was obtained by classifying chips according to whether they are included in the range of 10 mm or more and 2.00 mm or less, and determining the mass ratio of chips that are included in this range (suitable chips) and chips that are not included in this range (unsuitable chips).

Next, an emulsion type polyethylene wax (manufactured by Big Chemie Japan Co., Ltd., product number "AQUACER 531", melting point 130° C.) was added as a wax to the above-mentioned pulverized product and mixed to obtain a mixture. The wax addition rate is as shown in Table 1.

Next, a cylindrical compressed product (pellet) with an outer diameter of 8 mm and a length of 30 mm was obtained from the above mixture using a pelletizer (flat die molding machine). The specific gravity and moisture content of this compressed product are as shown in Table 1.

Next, the compressed product was placed in a pressure refiner, steamed at 170°C for 5 minutes, defibrated, and dried with a jet dryer at 200°C to obtain wood fibers. After adding diphenylmethane diisocyanate (MDI) as an adhesive to the wood fibers, the wood fibers were molded at 180° C. for 90 seconds to obtain a fiber board with a thickness of 3 mm and a density of 800 kg/m ³ . Note that the amount of adhesive added was 5% by mass.

(2) Example 2
A pulverized product was obtained in the same manner as in Example 1 except that the openings of the two sieves were changed. The average chip length, average chip diameter, and preferred chip content of this pulverized product are as shown in Table 1.

Next, a compressed product was obtained in the same manner as in Example 1 except that the wax addition rate was changed. The specific gravity and moisture content of this compressed product are as shown in Table 1.

Then, a fiber board was manufactured in the same manner as in Example 1 using the above compressed product. Note that the thickness and density of the fiber board of Example 2 are the same as those of the fiber board of Example 1.

(3) Example 3
A pulverized product was obtained in the same manner as in Example 1 except that the openings of the two sieves were changed. The average chip length, average chip diameter, and preferred chip content of this pulverized product are as shown in Table 1.

Next, a compressed product was obtained in the same manner as in Example 1, except that an emulsion type paraffin wax (manufactured by Big Chemie Japan Co., Ltd., product number "AQUACER 498", melting point 60°C) was used as the wax. The specific gravity and moisture content of this compressed product are as shown in Table 1.

Then, a fiber board was manufactured in the same manner as in Example 1 using the above compressed product. Note that the thickness and density of the fiber board of Example 3 are the same as those of the fiber board of Example 1.

(4) Example 4
A pulverized product was obtained in the same manner as in Example 1, except that the trunk of a coconut palm was used as the raw material for the fiber board (coconut family plant) and the openings of the two sieves were changed. The average chip length, average chip diameter, and preferred chip content of this pulverized product are as shown in Table 1.

Next, a compressed product was obtained in the same manner as in Example 1. The specific gravity and moisture content of this compressed product are as shown in Table 1.

Then, a fiber board was manufactured in the same manner as in Example 1 using the above compressed product. Note that the thickness and density of the fiber board of Example 4 are the same as those of the fiber board of Example 1.

(5) Example 5
A pulverized product was obtained in the same manner as in Example 1 except that the openings of the two sieves were changed. The average chip length, average chip diameter, and preferred chip content of this pulverized product are as shown in Table 1.

Next, a compressed product was obtained in the same manner as in Example 1. The specific gravity and moisture content of this compressed product are as shown in Table 1.

Then, a fiber board was manufactured in the same manner as in Example 1 using the above compressed product. Note that the thickness and density of the fiber board of Example 5 are the same as those of the fiber board of Example 1.

(6) Example 6
A pulverized product was obtained in the same manner as in Example 1 except that the openings of the two sieves were changed. The average chip length, average chip diameter, and preferred chip content of this pulverized product are as shown in Table 1.

Next, a compressed product was obtained in the same manner as in Example 1. The specific gravity and moisture content of this compressed product are as shown in Table 1.

Then, a fiber board was manufactured in the same manner as in Example 1 using the above compressed product. Note that the thickness and density of the fiber board of Example 6 are the same as those of the fiber board of Example 1.

(7) Example 7
A pulverized product was obtained in the same manner as in Example 1 except that the openings of the two sieves were changed. The average chip length, average chip diameter, and preferred chip content of this pulverized product are as shown in Table 1.

Next, a compressed product was obtained in the same manner as in Example 1 except that the wax addition rate was changed. The specific gravity and moisture content of this compressed product are as shown in Table 1.

Then, a fiber board was manufactured in the same manner as in Example 1 using the above compressed product. Note that the thickness and density of the fiber board of Example 7 are the same as those of the fiber board of Example 1.

(8) Comparative Example A pulverized product was obtained in the same manner as in Example 5. The average chip length, average chip diameter, and preferred chip content of this pulverized product are as shown in Table 1.

Next, a compressed product was obtained in the same manner as in Example 5, except that wax was not used. The specific gravity and moisture content of this compressed product are as shown in Table 1.

Then, a fiber board was manufactured in the same manner as in Example 5 using the above compressed product. Note that the thickness and density of the fiber board of the comparative example are the same as the thickness and density of the fiber board of Example 1.

2. Test (1) Water resistance The compressed product was immersed in water at 25°C. The compressed material was held at a depth of 3 cm. The compressed product was taken out of the water 10 seconds after immersion, and the swelling state (shape of the compressed product) of the compressed product was observed. The observation results were classified according to the following evaluation criteria and water resistance was evaluated.

<Evaluation criteria>
A: No swelling is observed (shape is maintained)
B: Slight swelling is seen (part of the shape has collapsed)
C: Swelling is seen more than B (shape is collapsed).

(2) Strength The bending strength of the fiberboard was measured in accordance with "JIS A 5905 Fiberboard." The measured values were classified according to the following evaluation criteria and the strength was evaluated.

<Evaluation criteria>
A: Bending strength is 25 MPa or more B: Bending strength is 20 MPa or more and less than 25 MPa C: Bending strength is less than 20 MPa.

(3) Surface smoothness The center line average roughness Ra of the fiber board was measured in accordance with "JIS B 0601 Surface Roughness". The measured values were classified according to the following evaluation criteria, and the surface smoothness was evaluated.

<Evaluation criteria>
A: Ra is 5 μm or less B: Ra is more than 5 μm and less than 15 μm C: Ra is more than 15 μm.

As for the strength of the fiber boards, Examples 1 to 7 were superior to Comparative Examples, confirming that the addition of wax to the crushed product of palm plants is effective.

Furthermore, regarding the surface smoothness of the fiber board, Examples 1 to 5 and 7 were superior to Example 6, confirming that a suitable chip content of 70% by mass or more is effective. .

Regarding the water resistance of the compressed product, Examples 1 to 6 were superior to Example 7, confirming that a wax addition rate of more than 0.05% by mass was effective. In addition, since wax was not used in the comparative example, it was confirmed that the water resistance of the compressed product was worse than that in Example 7.

1 Compressed material for fiber board production (compressed material)
2 Wood fiber 3 Molding machine 4 Die 40 Through hole 41 First surface 42 Second surface 5 Compression roller

Claims (5)

a compression step of compressing a mixture of a crushed product of a palm plant and wax to obtain a compressed product;
a steaming and defibrating step for obtaining wood fibers by steaming and defibrating the compressed material;
a forming step in which a mat-like molded product is obtained by adding an adhesive to the wood fibers and molding the wood fibers;
a hot-pressing step of pressing the mat-like molded product while heating it;
Method of manufacturing fiberboard. The pulverized product is obtained by pulverizing the palmaceous plant and then classifying it to reduce the amount of parenchymal tissue.
A method for manufacturing a fiberboard according to claim 1. The pulverized material contains 70% by mass or more of chips having a length of 0.6 mm or more and 50.0 mm or less and an outer diameter of 0.10 mm or more and 2.00 mm or less based on the total mass of the pulverized material.
A method for manufacturing a fiberboard according to claim 1. a die having a first surface, a second surface opposite to the first surface, and a through hole penetrating from the first surface to the second surface; and a compression roller rolling on the first surface. Using a molding machine equipped with,
Supplying the mixture to the first surface, pressing the mixture into the through-hole with the compression roller and compressing it to form the compressed product, and extruding the compressed product from the second surface.
A method for manufacturing a fiber board according to any one of claims 1 to 3. A mixture of crushed coconut and wax is compressed,
Compressed material for manufacturing fiberboard.

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