A hibiscus wood-based panel and its preparation method

Abstract

The present invention relates to the technical field of wood-based panels, and discloses a hibiscus wood-based panel and a preparation method thereof. The wood-based panel comprises wood fiber bundles, veneer fiber bundles, and an adhesive, and is formed by mixing and pressing the wood fiber bundles, the veneer fiber bundles, and the adhesive. The lengths of the wood fiber bundles are all 15-25 mm, and the diameters are all 0.5-1.5 mm. The wood fiber bundles comprise a plurality of wood fine fibers connected to each other horizontally, and the diameters of the wood fine fibers are 0.2-1.0 mm. The lengths of the veneer fiber bundles are all 15-25 mm, and the diameters are all 0.5-1.5 mm. The veneer fiber bundles comprise a plurality of veneer fine fibers connected to each other horizontally, and the diameters of the veneer fine fibers are 0.2-0.5 mm. The hibiscus wood-based panel of the present invention can be used to press the woody part and bark part of hibiscus to obtain a hibiscus wood-based panel with high mechanical strength and good stability by defining the morphology of the wood fiber bundles and veneer fiber bundles which are the main components of the wood-based panel.

Description

Technical Field

[0001] The invention relates to the technical field of artificial boards, and more specifically to an artificial board prepared by taking hibiscus wood as raw material, and also relates to a preparation method of the artificial board. Background Art

[0002] Hibiscus is a woody plant that combines medicinal, edible, ornamental, greening and fiber raw material values, and has high economic value. Hibiscus bark and hibiscus flower extracts, such as hibiscus bark extract essential oil or hibiscus flower extract essential oil, have the functions of insect repellent, deodorization and refreshing and are used to make various aromatherapy, or added in air purifier filters to assist in removing odors in the air and improving air quality. Hibiscus flower or hibiscus flower pollen also has the function of color adjustment, and is a natural food color enhancer. In addition, the hibiscus tree is easy to plant, and the yield rate is relatively high. Therefore, the artificial board prepared by the wood and / or flower of the hibiscus tree has the functions of insect repellent, deodorization and refreshing, and is an excellent board for processing and manufacturing wardrobes, wood veneers and floors.

[0003] Although hibiscus has many advantages, no one has used it as a raw material to prepare artificial boards in actual production, and there are no related patents or papers. The reason is that the hibiscus tree branches are thin and the bark ratio is high. It cannot be peeled before conventional chipping, which increases the difficulty of chipping. The bark part cannot be removed after chipping, which increases the difficulty of pressing. Summary of the invention

[0004] The purpose of the present application is to overcome at least one of the above technical problems and provide a method for preparing hibiscus artificial board.

[0005] In one aspect of the present application, a hibiscus artificial board is provided, which includes a wood fiber bundle, a veneer fiber bundle, and an adhesive and is formed by mixing and pressing the wood fiber bundle, the veneer fiber bundle and the adhesive; the wood fiber bundles are 15-25 mm in length and 0.5-1.5 mm in diameter, and the wood fiber bundles include a plurality of wood fine fibers that are laterally interconnected, and the diameter of the wood fine fibers is 0.2-1.0 mm; the veneer fiber bundles are 15-25 mm in length and 0.5-1.5 mm in diameter, and the veneer fiber bundles include a plurality of wood fine fibers that are laterally interconnected, and the diameter of the veneer fine fibers is 0.2-0.5 mm.

[0006] The main components of the artificial board in the prior art are mostly fibers and / or particles. Fibers or particles prepared from the bark part have the problem of difficult sizing. In other words, it is difficult for the adhesive to adsorb and penetrate the surface of the veneer fibers or veneer particles made of veneer part materials. Therefore, through the above products of the present invention, by defining the morphology of the wood fiber bundles and veneer fiber bundles, the morphology of the hibiscus fiber bundles (the wood fiber bundles and veneer fiber bundles are collectively referred to as hibiscus fiber bundles) can promote the absorption of the adhesive. Specifically, the gaps between multiple transverse interconnected wood / veneer fine fibers form new channels for absorbing adhesives in addition to the wood pores, and the new channels can absorb and store the adhesive. By increasing the sizing amount of the hibiscus fiber bundles through the formed new channels, the above problems are overcome to fully bond between the wood fiber bundles, between the veneer fiber bundles, and between the wood fiber bundles and the veneer fiber bundles, and then a hibiscus artificial board with high bonding strength is obtained.

[0007] On the other hand, the wood fiber bundles and veneer fiber bundles still maintain a certain diameter, and their internal network structures are also filled with adhesives, so a hibiscus artificial board with high mechanical strength can be obtained.

[0008] Furthermore, due to the presence of the veneer fiber bundles, the decorative effect of the artificial board is improved. Therefore, the artificial board of the present invention does not need to be surface-treated and can be directly used for the production of end products. This also enables the wood fiber bundles and veneer fiber bundles in the artificial board to fully release the functional components of preventing insects and refreshing, as well as the adsorption function.

[0009] In some embodiments, the surface of the artificial board has a pattern formed by staining with hibiscus pollen.

[0010] Hibiscus pollen is a natural food colorant, so the artificial board stained with it is safer and more environmentally friendly than the artificial board decorated with paint and decorative paper. At the same time, the hibiscus pollen present on the surface of the artificial board can release its own smell to promote the functions of preventing insects and refreshing of the artificial board.

[0011] In another aspect of the present application, a method for preparing a hibiscus artificial board is provided, which sequentially includes the processes of preparing fiber bundles, sizing, paving, pressing, and curing. The process of preparing fiber bundles is to cut the hibiscus tree branches into tree segments with a length of 15 - 30 mm, and then sequentially use rolling and cutting means to make the tree segments into hibiscus fiber bundles with a length of 15 - 25 mm and a diameter of 0.5 - 1.5 mm. The hibiscus fiber bundles include wood fiber bundles and veneer fiber bundles; the wood fiber bundles include multiple transverse interconnected wood fine fibers, and the diameter of the wood fine fibers is 0.2 - 1.0 mm; the veneer fiber bundles include multiple transverse interconnected veneer fine fibers, and the diameter of the veneer fine fibers is 0.2 - 0.5 mm.

[0012] The main components of wood-based panels in the prior art are mostly fibers and / or wood chips. The wood chips are prepared by a chipper, and the fibers are obtained by grinding the wood chips obtained by chipping. However, the bark proportion of the hibiscus tree is relatively high, and it is difficult for the chipper in the prior art to process it into wood chips suitable for the specifications of wood-based panels, let alone process it into fibers suitable for fiberboard. Therefore, through the above-mentioned solution of the present invention, first cut to a fixed length horizontally, then roll to form thick fiber bundles, and finally cut longitudinally into hibiscus fiber bundles of a defined specification. No chipping tools are used during processing, and there is no cutting parallel to the fiber direction. Therefore, hibiscus fiber bundles of a defined specification can be prepared, avoiding the problem that the bark damages the tools and affects the processing efficiency.

[0013] At the same time, by defining the morphology of the wood fiber bundles and the wood bark fiber bundles, the gaps between multiple horizontally interconnected fine wood / wood bark fibers form new channels for absorbing adhesives in addition to the pores of the wood. Thus, the morphology of the hibiscus fiber bundles (the wood fiber bundles and the wood bark fiber bundles are collectively referred to as hibiscus fiber bundles) can promote the absorption of the adhesive, thereby overcoming the above problems and enabling full gluing between the wood fiber bundles, the wood bark fiber bundles, and between the wood fiber bundles and the wood bark fiber bundles, and further obtaining a hibiscus wood-based panel with high gluing strength and mechanical strength.

[0014] In some embodiments, before rolling the tree segment, the tree segment is first made into wood chips with a width of 5 - 10 mm and a thickness of 5 - 10 mm by chipping.

[0015] In some embodiments, when rolling the tree segment, the rolling pressure provided by the rolling component and the rolling feed direction of the rolling component are both perpendicular to the fiber direction of the wood chips, thereby obtaining thick fiber bundles; when cutting the thick fiber bundles, the cutting direction of the cutting component is the same as the fiber direction of the thick fiber bundles, thereby obtaining the hibiscus fiber bundles.

[0016] In some embodiments, in the sizing process, the adhesive used is an isocyanate adhesive.

[0017] In some embodiments, the pressing process includes the following stages:

[0018] Pre-pressing stage: In the pre-pressing stage, first heat the continuous slab obtained through the matting process to 75 - 80 °C, and then apply pressure at a temperature of 95 - 100 °C with a compression amount of 8 - 12% to obtain a first blank;

[0019] Release stage: In the release stage, maintain the temperature of the first blank and remove the pressure until the first blank undergoes at least 25% compression rebound to obtain a second blank;

[0020] Hot pressing stage: In this hot pressing stage, first heat the second blank to 180 - 200 °C, then apply pressure at a temperature of 180 - 200 °C with a compression ratio of 12 - 15% to obtain the hibiscus artificial board.

[0021] For artificial boards prepared from bark or those with a relatively high bark content, problems such as delamination and cracking often occur during use. Those skilled in the art generally believe that this phenomenon is caused by the easy expansion of some materials in the bark due to moisture absorption. However, through long-term research, the inventor found that artificial boards stored under stable temperature and humidity conditions are also prone to the above phenomena, and the actual cause of these phenomena lies in the rebound of the bark part during the pressing process. Therefore, through the above method of the present invention, first, by defining the form of the wood bark fiber bundle, the voids between the fine wood bark fibers are filled with an adhesive, and the actual fine fiber form can have relatively little rebound and is easily fixed by the adhesive filled therein. Secondly, in the release stage, the relatively large compression rebound that the wood bark fiber bundle may have and the relatively small compression rebound that the wood fiber bundle may have are released. At this time, the form of the first blank that was only initially fixed in the pre-pressing stage is reorganized in the release stage, and finally, the final artificial board is obtained through secondary pressing in the hot pressing stage, thereby overcoming the problems of delamination and cracking caused by the rebound of the bark part in the artificial board.

[0022] Furthermore, because a relatively high curing temperature is used in the secondary pressing process of the above method, it can also improve the gluing performance.

[0023] In some embodiments, it further includes a process of dyeing the surface of the artificial board. This dyeing process is a humidity conditioning process in which the artificial board with freeze-dried pollen sprinkled on its surface is placed in a humid environment.

[0024] The pollen prepared from hibiscus flowers is a food-grade natural dye. Dyeing the surface of the artificial board with hibiscus pollen is safer and more environmentally friendly compared to paint or other chemical dyes. Conventional implementation schemes include: (1) Mixing fresh hibiscus flowers, dried hibiscus flowers or hibiscus pollen into the wood fiber bundle and wood bark fiber bundle before hot pressing for color adjustment. However, fresh hibiscus flowers, dried hibiscus flowers or hibiscus pollen cannot withstand the excessively high hot pressing temperature during pressing and turn into a black paste after pressing, which instead affects the decorative effect of the artificial board. (2) Roller-coating the surface of the pressed artificial board with hibiscus flower extract or aqueous solution. However, if a color fixative is added to the extract or aqueous solution, the meaning of the natural dye is lost, and it is difficult to fix the color without using an additional color fixative.

[0025] Therefore, through the above solution of the present invention, freeze-dried pollen is first prepared by freeze-drying means to obtain dyed particles with a relatively high porosity. Then, the freeze-dried pollen is spread on the surface of the artificial board, and through a moisture absorption method, part of the pollen is dissolved and penetrates into the surface of the artificial board, and the remaining undissolved pollen particles are carried into the pores of the artificial board. Because the wood fiber bundles and veneer fiber bundles that make up the surface of the artificial board have a porous structure, the pollen entering the surface in this way replaces the moisture in the surface pores of the artificial board and is not easily separated and is fixed on the surface of the artificial board.

[0026] In some embodiments, the humid environment refers to an environment with a temperature of 28 - 36°C and a humidity of at least 90% RH.

[0027] In some embodiments, before the dyeing process, the artificial board has a moisture content gradient in its thickness direction, and its surface has the lowest moisture content, and the lowest moisture content is 3 - 5%.

[0028] In some embodiments, the freeze-dried pollen is obtained by grinding freeze-dried hibiscus flowers.

[0029] In summary, the hibiscus artificial board of the present invention can utilize the woody part and bark part of hibiscus to press and obtain a hibiscus artificial board with relatively high mechanical strength and good stability by defining the morphology of the wood fiber bundles and veneer fiber bundles that are the main components of the artificial board. The preparation method of the hibiscus artificial board of the present invention first cuts to a fixed length horizontally, then rolls to form thick fiber bundles, and finally cuts longitudinally into hibiscus fiber bundles of a defined specification. No chip-cutting tools are used in the processing, and no cutting parallel to the fiber direction is involved. Therefore, hibiscus fiber bundles with specified fibers can be prepared, avoiding the problem that the bark damages the tools and affects the processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0031] Figure 1 It is a product photo of the hibiscus artificial board of the embodiment of the present application.

[0032] Figure 2a It is a photo of the hibiscus artificial board of the embodiment of the present application after being soaked in water for 24 hours.

[0033] Figure 2b It is a photo of the hibiscus artificial board of the comparative example after being soaked in water for 24 hours.

[0034] Figure 3 It is a schematic structural diagram of a humid environment according to an embodiment of the present application.

[0035] In the figure: 1, wood fiber bundle; 2, veneer fiber bundle; 3, artificial board; 4, belt conveyor; 5, air duct; 6, atomized water nozzle. Embodiment

[0036] In order to enable those skilled in the art to better understand the technical solutions in the present application, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application. Embodiment

[0037] The preparation method of the hibiscus artificial board used in the first embodiment of the present invention sequentially includes the processes of preparing fiber bundles, applying glue, paving, pressing, and curing.

[0038] A. The process of preparing fiber bundles includes a cutting stage, a rolling stage, and a cutting stage.

[0039] A(a) In the cutting stage, the hibiscus tree branches are cut into tree segments with a length of 15 - 30 mm. The hibiscus tree branches have the form directly obtained after felling. The error in the cutting length is inevitably caused by factors such as cutting equipment or operations, but at least the length of the cut tree segments should not be shorter than 15 mm and should not be longer than 30 mm to ensure that the final length of the vast majority of the hibiscus fiber bundles can fall within the specified range.

[0040] A(b) In the rolling stage, any rolling device in the prior art is used to roll the wood segments obtained in the cutting stage. Since the length of the wood segments is 15 - 30 mm, the length of the coarse fiber bundles in the form of wood chips after rolling is in the range of 15 - 25 mm. The gap between the rolling member and the rolling workbench is controlled in a manner known to those skilled in the art to obtain coarse fiber bundles with a thickness within the specified range. In this embodiment, the thickness of the coarse fiber bundles is 0.5 - 1.5 mm. The error in the rolling gap of the rolling member and the difference in the mechanical strength of each part of the wood segment inevitably cause the error in the thickness of the coarse fiber bundles, but at least it should be within the range of 0.5 - 1.5 mm.

[0041] Preferably, when rolling the tree segments, the rolling pressure provided by the rolling member and the rolling feed direction of the rolling member are both perpendicular to the fiber direction of the wood chips, so that more coarse fiber bundles can meet the required form.

[0042] As a further preference, before rolling the tree segments, the tree segments are first made into wood chips with a width of 5-10 mm and a thickness of 5-10 mm by means of chipping. In this preferred method, the specifications of the wood chips can be achieved by the chipper and will not cause damage to the chipper due to excessive cutting.

[0043] A(c) In the cutting stage, a wire sawing machine, a frame sawing machine or other equipment of the prior art is used to cut the coarse fiber bundle along the fiber direction of the coarse fiber bundle, and finally a hibiscus fiber bundle with a length of 15-25 mm and a diameter of 0.5-1.5 mm is obtained. In fact, in the rolling stage, some wood segments are directly rolled into the form of fiber bundles, while some intermediate substances (coarse fiber bundles) in the form of wood chips need to be cut to make them in the form of fiber bundles. Preferably, the cutting direction of the cutting component is the same as the fiber direction of the coarse fiber bundle, so that more hibiscus fiber bundles can meet the required form.

[0044] The hibiscus tree branches used in the process of preparing the fiber bundle have not had their bark removed, so the hibiscus fiber bundles obtained in this process actually include wood fiber bundles and bark fiber bundles. At the same time, in this embodiment, the rolling method is used to obtain the wood fiber bundles, so the wood fiber bundles include multiple wood fine fibers connected horizontally to each other, and the diameter of the wood fine fibers is 0.2-1.0 mm. Similarly, the bark fiber bundles include multiple bark fine fibers connected horizontally to each other. The bark is more likely to break during the rolling process, so the diameter of the bark fine fibers in the actually obtained bark fiber bundles is 0.2-0.5 mm. Therefore, this method can make full use of this situation. There are more adhesive channels formed by the gaps between the bark fine fibers in the bark fiber bundles, and when the wood fiber bundles have a normal sizing amount, only the sizing amount of the bark fiber bundles needs to be increased.

[0045] B. Any method in the prior art can be used in the sizing process, preferably the dipping method, and of course the spraying method is also feasible. For the purpose of improving the bonding strength, the adhesive used is an isocyanate adhesive.

[0046] C. Any method in the prior art can be used in the laying process to form the sized hibiscus fiber bundles into a continuous slab.

[0047] D. Any method in the prior art can be used in the pressing process, but preferably, the pressing process includes a pre-pressing stage, a release stage and a hot-pressing stage.

[0048] D(a) In the pre-pressing stage, the continuous slab obtained through the laying process is first heated to 77±2°C, and then pressed at a temperature of 97±2°C to obtain a first blank. The set compression ratio is 10%, but in fact, due to the difference in the hardness of the material, there will be a deviation in the actual compression ratio. Generally speaking, the actual compression ratio is 8-12%.

[0049] D(b) In the release stage, the pressure is removed while maintaining the temperature of the first blank until at least 25% of the compression springback occurs in the first blank, obtaining the second blank. Preferably, when 25 - 30% of the compression springback occurs, the hot pressing stage is started.

[0050] D(c) In the hot pressing stage, first heat the second blank to 180 - 200 °C, and then apply pressure at a temperature of 180 - 200 °C. An actual compression amount of 12 - 15% can meet the requirements, obtaining the wood-based panel. The hot pressing temperature can be selected as 185 ± 2 °C, 190 ± 2 °C, or 195 ± 2 °C. Within the temperature range of 180 - 200 °C, the influence on the properties of the wood fiber bundles, veneer fiber bundles, and adhesives is not significant. Therefore, the hot pressing temperatures within this range are all acceptable.

[0051] E. The curing process is to adjust the moisture content of the wood-based panel prepared after the pressing process to the range that meets the usage requirements using the equipment and methods of the prior art.

[0052] Figure 1 The hibiscus wood-based panel prepared by using the method of the present invention is shown, with a thickness of 16 mm. It includes wood fiber bundles 1, veneer fiber bundles 2, and an adhesive and is formed by mixing and pressing the wood fiber bundles, veneer fiber bundles, and the adhesive. The lengths of the wood fiber bundles 1 are all 15 - 25 mm, and the diameters are all 0.5 - 1.5 mm. The wood fiber bundles 1 include multiple wood fibers connected transversely to each other, and the diameters of the wood fibers are 0.2 - 1.0 mm; the lengths of the veneer fiber bundles 2 are all 15 - 25 mm, and the diameters are all 0.5 - 1.5 mm. The veneer fiber bundles 2 include multiple veneer fibers connected transversely to each other, and the diameters of the veneer fibers are 0.2 - 0.5 mm.

[0053] Table 1 shows the physical and chemical properties of the hibiscus wood-based panel prepared by using the method of the present invention. The reference for comparison is the eucalyptus particleboard with a thickness of 16 mm that meets the standard requirements, and the hibiscus wood-based panel prepared by using the method of the comparative example. The method of the comparative example is the traditional method, that is, the hibiscus tree branches are processed by chipping. As described above, limited by the material characteristics of the hibiscus tree branches, the chipper can process the hibiscus tree branches to obtain chips with a length of 15 - 25 mm and a width of 2.5 - 3 mm. The chips include wood chips and veneer chips. After mixing with an isocyanate adhesive, the hibiscus wood-based panel (particleboard) of the comparative example is pressed at a hot pressing temperature of 180 - 200 °C, with a thickness of 16 mm.

[0054] Figure 2a The photo of the effect of the hibiscus wood-based panel prepared by using the method of the present invention after being soaked in water for 24 hours is shown, Figure 2bThe following shows the effect photo of the hibiscus wood-based panel of the control example after being soaked in water for 24 hours. It can be clearly seen from the comparison between Figure 2a and Figure 2b that the water immersion performance of the hibiscus wood-based panel prepared by the method of the present invention is better, and it can still maintain a good shape after being soaked in cold water for 24 hours.

[0055] Table 1. Physical and chemical properties of hibiscus wood-based panel

[0056] Group Modulus of rupture (MOR) Modulus of elasticity (MOE) Internal bond strength Unit MPa MPa MPa This application 12.0 2150 0.39 Eucalyptus particleboard 12.5 2100 0.40 Control example 10.3 1400 0.25

[0057] As a preferred embodiment, the surface of the pressed wood-based panel is dyed. In particular, the process of F. dyeing is a process of humidifying the wood-based panel with freeze-dried pollen sprinkled on its surface in a humid environment.

[0058] Specifically, the dyeing process includes a pollen production stage, a moisture content adjustment stage, a sprinkling stage, and a humidifying stage, where the pollen production stage and the moisture content adjustment stage have no prior or subsequent order.

[0059] F(a) In the pollen production stage, freeze-dried hibiscus flowers are first prepared by the method of the prior art, and then the freeze-dried hibiscus flowers are crushed by means such as grinding to obtain freeze-dried pollen with a particle size of 0.3-0.5 mm.

[0060] F(a) In the moisture content adjustment stage, the wood-based panel has a moisture content gradient in its thickness direction, so that its surface has the lowest moisture content, and the lowest moisture content is 3-5%; its bottom surface has the highest moisture content, and the highest moisture content is 10-12%.

[0061] F(b) In the sprinkling stage, the freeze-dried pollen is evenly sprinkled on the surface of the wood-based panel, and the sprinkling amount is 15-20 g / m 2 .

[0062] F(c) In the humidifying stage, the wood-based panel is placed in a humid environment for 15-20 min. The humid environment refers to an environment with a temperature of 28-36 °C and a humidity of at least 90% RH. There are various ways to implement the humidifying stage. One feasible way is to place the wood-based panel in a constant temperature and humidity room, which can control the temperature at 28-36 °C and the humidity at 92% RH, and the preferred temperature is 35 °C. Another feasible and more preferred embodiment is to place the wood-based panel under the atomized water vapor. Please refer to Figure 3As shown, the wood-based panel 3 is placed on a belt conveyor 4 of the prior art and conveyed by it. Above the wood-based panel 3, there is an air duct 5 with a flat structure. On the bottom surface of the air duct 5 facing the wood-based panel 3, there are a plurality of atomizing water spray nozzles 6. The atomizing water spray nozzles 6 can spray atomized water at a temperature of 35°C, and there is a spacing of 15 - 20 cm between the atomizing water spray nozzles 6 and the conveying working surface of the belt conveyor 4.

[0063] The wood-based panel 3 can stay below the atomizing water spray nozzles 6 for 15 - 20 minutes, or the length of the air duct 5 can be extended and the conveying speed of the belt conveyor 4 can be controlled, so that the time for the wood-based panel 3 to pass through the section of the air duct 5 is 15 - 20 minutes. Generally speaking, the length of time the wood-based panel 3 is located below the atomizing water spray nozzles 6 can be any one of 15 - 20 minutes. Theoretically, if it is less than 15 minutes, the lyophilized pollen will not absorb moisture and penetrate sufficiently, and if it is more than 20 minutes, condensed water is likely to form on the surface of the wood-based panel 3. Condensed water should be avoided to ensure that the lyophilized pollen dissolves in the form of moisture absorption and penetrates into the wood-based panel 3, rather than dissolving in water.

[0064] Table 2 shows the color fastness performance of the dyed hibiscus wood-based panel prepared by using the method of the present invention. The dyed hibiscus wood-based panel prepared by using the method of the comparative example is used as a comparison reference. The method of the comparative example is the traditional method, that is, the hibiscus flower extract is diluted with water and then brushed on the surface of the wood-based panel.

[0065] Table 2. Color fastness performance of the dyed hibiscus wood-based panel

[0066]

[0067]

[0068] It can be learned from Table 2 that although the color fastness performance of the dyed hibiscus wood-based panel prepared by the method of the present invention still cannot reach an ideal state, it has made progress compared with the prior art.

[0069] The above description is for illustrative purposes and not for limitation. By reading the above description, many embodiments and many applications other than the provided examples will be obvious to those skilled in the art. Therefore, the scope of this teaching should not be determined with reference to the above description, but should be determined with reference to the appended claims and the full scope of the equivalents of these claims. For the sake of completeness, all articles and references including patent applications and published announcements are incorporated herein by reference. Omitting any aspect of the subject matter disclosed herein in the foregoing claims is not intended to abandon such subject matter, nor should it be considered that the applicant has not considered such subject matter as part of the disclosed subject matter of the application.

Claims

1. A preparation method of hibiscus artificial board, sequentially including the processes of preparing fiber bundles, sizing, matting, pressing, and curing, characterized in that, The process of preparing the fiber bundle is to cut the hibiscus tree branches into tree segments with a length of 15 - 30 mm, and then sequentially use rolling and cutting means to make the tree segments into hibiscus fiber bundles with a length of 15 - 25 mm and a diameter of 0.5 - 1.5 mm. The hibiscus fiber bundles include wood fiber bundles and wood bark fiber bundles; the wood fiber bundles include multiple wood fine fibers connected to each other horizontally, and the diameter of the wood fine fibers is 0.2 - 1.0 mm; the wood bark fiber bundles include multiple wood bark fine fibers connected to each other horizontally, and the diameter of the wood bark fine fibers is 0.2 - 0.5 mm. Before rolling the tree segments, first use chipping means to make the tree segments into wood chips with a width of 5 - 10 mm and a thickness of 5 - 10 mm. When rolling the tree segments, the rolling pressure provided by the rolling component and the rolling feed direction of the rolling component are both perpendicular to the fiber direction of the wood chips, so as to obtain a coarse fiber bundle; when cutting the coarse fiber bundle, the cutting direction of the cutting component is the same as the fiber direction of the coarse fiber bundle, so as to obtain the hibiscus fiber bundle. The preparation method further includes a process of dyeing the surface of the artificial board. The dyeing process is a process of humidity conditioning the artificial board with freeze-dried pollen sprinkled on its surface in a humid environment. The humid environment refers to an environment with a temperature of 28 - 36°C and a humidity of at least 90% RH. Before the dyeing process, the artificial board has a moisture content gradient in its thickness direction, and its surface has the lowest moisture content, and the lowest moisture content is 3 - 5%.

2. The preparation method of the hibiscus artificial board according to claim 1, characterized in that, In the sizing process, the adhesive used is an isocyanate adhesive.

3. The preparation method of the hibiscus artificial board according to claim 2, wherein The pressing process includes the following stages: Pre-pressing stage, in this pre-pressing stage, first heat the continuous slab obtained through the matting process to 75 - 80°C, and then apply pressure at a temperature of 95 - 100°C, with a compression amount of 8 - 12%, to obtain a first blank. Release stage, in this release stage, maintain the temperature of the first blank and remove the pressure until the first blank undergoes at least 25% compression rebound to obtain a second blank. Hot-pressing stage, in this hot-pressing stage, first heat the second blank to 180 - 200°C, and then apply pressure at a temperature of 180 - 200°C, with a compression amount of 12 - 15%, to obtain the artificial board.

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