JP3541796B2 - Manufacturing method of hollow panel - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a hollow panel, and is capable of obtaining a high-rigidity and light-weight hollow panel formed by laminating plate materials made of fibers or wood elements.
[0002]
[Prior art]
In recent years, the shortage of timber resources and the protection of forests have become problems, and it is clear that deforestation will become increasingly difficult in the future. Therefore, it is expected that the supply of plate materials such as plywood manufactured using a large amount of raw wood will be unstable or insufficient, and the price will rise. Therefore, wood panels obtained by effectively using wood thin pieces and wood pieces that have been conventionally discarded wood have attracted attention, and their application to applications that conventionally used plywood has been strongly desired.
[0003]
As such a wood panel, for example, those shown in FIGS. 8, 9, and 10 are known.
The wooden panel shown in FIG. 8 is formed by stacking wooden flat plates 2 and 2 thinner than the paper honeycomb 1 on both sides of the paper honeycomb 1.
The wood panel shown in FIG. 9 has a surface layer 4 formed of a wood thin piece integrated board on both sides of the core material 3 which is thinner than the core material 3 and which is formed by bonding and integrating the wood thin pieces using a binder. , 4 are stacked.
Further, the wooden panel shown in FIG. 10 is obtained by sandwiching a corrugated plate 5 formed of resin or the like between wooden flat plates 6.
[0004]
The wood panels shown in FIGS. 8, 9 and 10 are excellent in that they are high in rigidity and lightweight, but have a problem that the manufacturing process is complicated and the manufacturing cost is high.
[0005]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to provide a method for manufacturing a hollow panel capable of inexpensively obtaining a high-rigidity, lightweight hollow panel formed by laminating plate materials made of fibers or wood elements.
[0006]
[Means for Solving the Problems]
In order to solve such a problem, a method for manufacturing a hollow panel according to claim 1 of the present invention includes laminating a fiber or a wood element to which a binder is attached together with a plurality of cores, and hot-press molding the laminate integrally.
After the hot pressing, the core is pulled out to form a hole having a rib.
[0007]
In the method for manufacturing a hollow panel according to a second aspect of the present invention, the wooden element is a wooden thin piece.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
FIG. 1 is a schematic perspective view showing an example of a panel obtained by the method for manufacturing a hollow panel of the present invention.
In the panel 10 of this example, a binder is attached to a fiber or a wood element, and then the fiber or the wood element to which the binder is attached is laminated together with a plurality of cores, and the laminate is integrally hot-pressed and formed with a binder. The core is integrally formed, and after hot pressing, the core is pulled out of the molded product, and a plurality of holes 11 separated by ribs 12 are formed so as to penetrate in the longitudinal direction of the panel 10.
[0009]
Examples of the fibers used in the present invention include plant-based fibers such as grass, stem, and straw, and fibers (fleece) obtained by defibrating a cloth. Examples of the wood element include wood flakes, wood fibers, wood chips, wood particles, and the like. In particular, if it is a thin piece of wood, the strength required as a building material can be obtained.
Here, a method for manufacturing a hollow panel of the present invention will be described with reference to FIGS.
The woody flakes used in the present invention are not particularly limited, and various softwood and hardwood flakes can be used. Specific examples include flakes of aspen, radiata pine, lodgepole pine, cedar, hinoki, red pine, spruce pine, fir pine and the like.
These hardwood or coniferous woods are sliced using a disk flaker or the like.
[0010]
The woody flake used in the present invention preferably has an absolute thickness of 0.05 to 1.0 mm and an average thickness of 0.10 to 0.45 mm, but is not limited thereto. Not something. Here, the absolute value of the thickness of the wooden flake means the minimum and maximum thickness when 200 or more wooden flakes to be used are extracted at random, and the average value of the thickness is the extracted sample (wood material). Means the average value of the thickness of the flakes. If the absolute value of the thickness of the woody flakes is less than 0.05, the strength and rigidity of the panel obtained by molding the woody flakes decrease, the bulk at the time of forming before pressing increases, and productivity becomes disadvantageous. At the same time, the density after molding increases. On the other hand, when the absolute value of the thickness exceeds 1.0 mm, the smoothness of the surface decreases.
[0011]
Further, the length of the thin wooden piece is preferably in the range of 20.0 to 150.0 mm. The length of the woody flake is appropriately selected according to the shape of the molded product. The absolute value of the length of the thin wood piece is preferably within ± 10 mm with respect to the target length (average value). Here, the absolute value of the length of the wood slice means the minimum and maximum lengths when 50 or more wood slices to be used are extracted at random, and the average length is the target value. Means
[0012]
Moreover, it is preferable that the absolute value of the width | variety of a woody flake is in the range of 5.00-50.00 mm, and the average value is in the range of 5.00-35.00 mm. Here, the absolute value of the width of the woody slice means the minimum and maximum width when 50 or more woody slices to be used are extracted at random, and the average value of the width is the value of the extracted sample (woody slice). It shall mean the average value of the width. If the absolute value of the width of the woody flakes is less than 1.00 mm, poor adhesion in the width direction occurs, causing a decrease in strength. Further, if the absolute value of the width exceeds 50.00 mm, the woody flakes are easily curled or bent, and the binder does not easily adhere to the bent inside when mixed with the binder. (Bubble) is likely to be generated, and as a result, the woody flakes are peeled off, and further, the smoothness of the surface of the obtained hollow panel is reduced.
[0013]
The arrangement of the woody flakes forming the panel 10 is not particularly limited, but may be one in which the grain direction is aligned substantially in one direction, or may be a three-layer structure, and the adjacent layers may be arranged. The grain direction of the thin wood piece may be the orthogonal direction, and the grain direction of the lower layer may be the parallel direction. Furthermore, the ratio of the thin wooden pieces arranged in the same direction can be changed according to the strength and rigidity of the target panel 10. The grain direction of the thin wooden piece may be random.
[0014]
As the binder used in the present invention, any of a foamable binder resin which foams itself, a non-foamable binder resin, and a mixture thereof can be used. Among them, a foamable binder resin is preferably used. Foamable binder resin reduces the amount of resin used by allowing resin to be present only at the intersections of the woody flakes and expanding the small gaps between the woody flakes with foam cells, resulting in a hollow panel that can be obtained. 10 can be reduced in density. Furthermore, the heat insulation and soundproof effect of panel 10 can be improved by the foam cell.
[0015]
As the foamable binder resin, any of a self-foaming foamable resin, or a mixed foamable resin obtained by adding a foaming agent to a non-foamable resin such as phenol, urea, epoxy, or acrylic may be used. It is preferable to be made of a self-foaming foamable resin from the viewpoint of improving and obtaining a wooden hollow panel having a low density. Examples of the self-expanding foamable resin include a foamable polyurethane resin, an isocyanate-based resin, and preferably PMDI (polymeric MDI or crude MDI). When an expandable polyurethane resin or an isocyanate-based resin is used, it easily reacts with moisture, and the isocyanate group (—NCO) reacts with water to self-expand, so that the reaction time is shortened and the press time can be reduced.
[0016]
In particular, when PMDI is used, the adhesive strength of the binder becomes strong. In addition, since the PMDI foams and cures at a low temperature, the reaction time is fast. Specifically, the temperature at the time of hot pressing can be lowered to about 140 to 200 ° C., and further to about 140 to 180 ° C. Since the sheet thickness (mm) can be as short as about 10 to 15 seconds, the hot pressing step can be shortened. In addition, when PMDI is used as a binder, the molding temperature is as low as 140 to 180 ° C. as described above, so that the decomposition of the release agent can be suppressed, the mold releasability is good, and the molding work efficiency is improved. .
[0017]
The ratio of the binder to the woody flakes constituting the panel 10 is preferably 3.5 to 20 parts by weight based on 100 parts by weight (absolute dry weight) of the woody flakes. By changing the amount of the binder added, the density and strength of the obtained panel 10 can also be changed.
If necessary, a curing agent, a curing catalyst, a curing accelerator, a diluent, a thickener, a dispersant, a water repellent, and the like may be added to the binder.
[0018]
Further, it is preferable that the woody flakes are acetylated in advance. When acetylating woody flakes, the woody flakes are dried to a water content of 3% or less, preferably 1% or less, and then brought into contact with vaporized vapor such as acetic acid, acetic anhydride, chloroacetic acid, etc. in the gas phase. Acetylation (acetylation degree 12 to 20%) is preferred. By acetylating the woody flakes in this manner, water resistance is obtained, and dimensional stability can be imparted to the panel 10.
[0019]
Next, a binder for bonding the wooden flakes is attached to the surface of the wooden flakes. The mixing of the woody flakes and the binder is usually performed by a spraying method. For example, a method in which a wood thin piece whose size and moisture content are adjusted as described above is placed in a rotating drum rotating at a low speed, and a spray is applied to the wood thin piece with a binder when the wood thin piece falls naturally in the rotating drum. Is preferred.
[0020]
When a binder is applied to a thin wooden piece by a spray method, the binder is dissolved in a solvent in advance and applied as a solution. When using a spray device having good uniform dispersion, dilution with a solvent is unnecessary.
Next, the wood flakes having the binder adhered to the wood flakes are dried and removed of a solvent such as water or acetone contained in the binder, and then formed using a press molding machine to form the panel 10.
[0021]
As shown in FIG. 2, a forming plate 15 is provided at the bottom of a forming frame 14 having a length of 800 to 2500 mm, a width of 800 to 1300 mm, and a height of 50 to 300 mm, and a binder for forming a lower flat plate portion of the panel 10 is provided. The applied wood thin pieces 17 are sprayed to form a first layer (a portion in the figure).
Next, cores 18 made of trapezoidal aluminum rods for forming the holes 11 shown in FIG. 1 are arranged at equal intervals on the first layer of the wooden thin piece 17. Further, a thin wooden piece 17 forming the panel 10 is sprayed on the core 18 to form a second layer (portion b in the drawing).
Next, the cores 18 are arranged at equal intervals on the second layer of the wooden thin pieces 17 so as to enter between the cores 18 arranged in the second layer. At this time, the trapezoidal shape of the core 18 arranged here is set to be upside down with the trapezoidal shape of the core 18 arranged in the second layer. Further, the thin wooden piece 17 forming the upper flat plate portion of the panel 10 is sprayed on the core 18 to form a third layer (portion c in the figure).
Next, the forming plate 16 is placed on the third layer.
[0022]
By the way, the core used in the present invention is not limited to a trapezoidal cross-sectional shape, but is a rod-shaped body having an arbitrary cross-sectional shape. The size of the cross-sectional shape of the core is appropriately determined according to the thickness of the panel to be formed.
Further, the core used in the present invention is made of a material such as metal which does not deform or deteriorate due to heat or pressure applied during hot pressing.
[0023]
Next, the laminate obtained by laminating the wood thin pieces 17 as described above is hot-pressed at a temperature of 140 to 220 ° C. and a pressure of 15 to 40 kg / cm ² for 6 to 15 minutes.
The laminate obtained by laminating the wood flakes 17 is hot-pressed to a thickness of 1/3 to 1/30, thereby obtaining the panel 10 in which the wood flakes are joined by the binder.
[0024]
Next, as shown in FIG. 3, after cooling the hot-pressed panel 10, the core 18 is pulled out from the panel 10. After the core 18 is pulled out, the outer periphery of the panel 10 is trimmed to obtain the panel 10 having a hollow structure.
A chip saw or the like is used for trimming the surface of the panel 10.
[0025]
The density of the panel 10 manufactured in this manner is 0.3 to 1.0 g / cm ³ , preferably 0.5 to 0.8 g / cm ^3, and is a so-called MDF, hard board, particle board, flake board, It is similar to a random strand board or a wafer board.
According to the method for manufacturing a hollow panel of the present invention, the core layer portion and the surface layer portion of panel 10 can be integrally formed, so that the manufacturing process is simplified and the manufacturing cost can be reduced. Further, since the panel 10 has a hollow structure, the weight can be reduced, and since the holes 11 forming the hollow structure serve as an air layer, the sound insulation and the heat insulation are improved. In addition, since the ribs 12 are provided between the holes 11 of the panel 10 and the both ends 13 in the horizontal direction of the panel 10 are thick walls, the rigidity of the panel 10 is improved.
[0027]
In addition, according to the present invention, as shown in FIG. 4, a male engaging portion 22 for joining is provided on one of both ends in the horizontal direction, and a female engaging portion 23 for joining is provided on the other, and In order to form the hollow-structured panel 20 having the holes 21, if the length of the wood fiber and the size of the wood flakes are made uniform, the wood mouth can be formed smoothly. Form a stop. In the case of integrally forming, the forming frame of the panel 20 is provided with the forming portions of the male locking portion 22 and the female locking portion 23, and the hot pressing is performed in the same manner as in the method of manufacturing the hollow panel shown in FIG. Thus, it can be easily formed integrally.
[0028]
Further, as shown in FIG. 5, the panel 30 has a structure in which a cable 33 is embedded in a rib 32 between the holes 31.
In order to form this panel 30 using the hollow panel manufacturing method of the present invention, when the core 18 shown in FIG. 2 is arranged, the cable 33 is arranged near the core 18, and thereafter, It is obtained by integrally molding by hot pressing. Examples of the cable 33 include a telephone line, an optical fiber cable, and an electric wire.
[0029]
Further, according to the present invention, as shown in FIG. 6, the panel 40 having irregularities in its outer shape can be integrally formed.
In this case, an uneven portion of the panel 40 is formed on a forming plate used for forming the panel 40, and hot pressing is performed using a core having an arbitrary shape in the same manner as in the method of manufacturing a hollow panel shown in FIG. Thus, it can be easily formed integrally.
Alternatively, a hollow panel having holes 41, 42, and 43 having a shape as shown in FIG. 6 is integrally formed by hot pressing, and the surface of the hollow panel is cut to form irregularities, thereby obtaining the panel 40. You can also.
Such a panel 40 is used for a decorative plate having a fixed width such as a door.
[0030]
Further, according to the present invention, as shown in FIG. 7, a panel 50 having irregularities in its outer shape can be integrally formed.
In this case, an uneven portion of the panel 50 is formed on a forming plate used for forming the panel 50, and hot pressing is performed using a core having an arbitrary shape in the same manner as in the method of manufacturing a hollow panel shown in FIG. Thus, it can be easily formed integrally.
Alternatively, a hollow panel having holes 51 and 52 having a shape as shown in FIG. 7 may be integrally formed by hot pressing, and the surface of the hollow panel may be cut to form irregularities, thereby obtaining the panel 50. it can.
Such a panel 50 is used for a frame such as a frame such as a door or a frame, a decorative frame or the like.
[0031]
Hereinafter, a specific example will be described with reference to FIG.
From a log having a water content of 80 to 130%, a wood flake 17 having a length of about 25 mm, a width of about 5 to 25 mm, and a thickness of 0.3 mm (average value) was prepared using a disk flaker.
Next, the thin wooden piece 17 was dried at 100 ° C. for 24 hours using a hot air dryer. The moisture content of the woody piece 17 after drying was about 2%.
[0032]
Next, 1533 g of the obtained wood thin pieces 17 were put in a rotating drum rotating at a low speed, and a binder was spray-coated when the wood thin pieces 17 dropped naturally in the drum.
As binders, 134 g of crude polymethylene diphenyl diisocyanate (manufactured by Sumitomo Bayer Urethane Co., trade name; Sumidur 44V20) and 89 g of aqueous phenol binder (manufactured by Gunei Chemical Industry Co., Ltd., trade name: REGITOP PL-4600) were added to 74 g of water. A dissolved solution, 60 g of paraffin wax emulsion (manufactured by Chukyo Yushi Co., Ltd., trade name: Cellozol 428) was used.
The coating amount of the binder was a ratio of Sumidur 44V20: 9 parts by weight, PL-4600: 3 parts by weight, and Cellosol 428: 2 parts by weight based on 100 parts by weight of the absolutely dry weight of the woody flakes 17.
The application order was an aqueous solution of Cellolsol 428, PL-4600, and Sumidur 44V20.
[0033]
Next, the moisture in the wood flake 17 to which the binder was applied was dried and removed, and then the wood flake 17 was formed using a press forming machine.
A forming plate 15 is provided at the bottom of a forming frame 14 having a length of 330 mm, a width of 300 mm, and a height of 300 mm, and a thin wood piece 17, 519 g coated with a binder for forming a lower plate portion of the panel 10 is sprayed. And
Next, cores 18 made of aluminum rods having a trapezoidal cross section are arranged at equal intervals on the first layer of the wooden piece 17. Further, 675 g of a thin wooden piece 17 coated with a binder for forming a hollow structure of the panel 10 is sprayed on the core 18 to form a second layer.
Next, the cores 18 are arranged at equal intervals on the second layer of the wooden thin pieces 17 so as to enter between the cores 18 arranged in the second layer. At this time, the trapezoidal shape of the core 18 arranged here is set to be upside down with the trapezoidal shape of the core 18 arranged in the second layer. Further, on the core 18, a wood layer 17, 696 g coated with a binder for forming the upper flat plate portion of the panel 10 is sprayed to form a third layer, and the total thickness of the laminate is about 120 mm.
A forming plate 16 for hot pressing is placed on the upper surface of the laminate.
[0034]
Next, a laminate having a thickness of about 120 mm was hot-pressed at a temperature of 180 ° C. for 8 minutes so as to have a thickness of 22 mm. At this time, the maximum pressure was 70 kg / cm ² .
Next, after cooling the hot-pressed panel 10 to room temperature, the core 18 was pulled out.
Next, after the core 18 is pulled out, the outer periphery of the panel 10 is trimmed using a tip saw, and the surface is ground using a wide belt sander # 120 to obtain a panel 10 having a length of 300 mm, a width of 270 mm and a thickness of 20 mm. Was.
[0035]
The density of the panel 10 thus obtained was measured using a density distribution measuring instrument standard ATR Density Profiling Type DPM2018 (manufactured by ATR) for measuring the density distribution (density profile) in the thickness direction. , 0.6 g / cm.
[0036]
【The invention's effect】
As described above, according to the method for manufacturing a hollow panel of the present invention, since the core layer portion and the surface layer portion of the hollow panel can be integrally formed, the manufacturing process is simplified, and the manufacturing cost can be reduced. it can. Further, since the panel has a hollow structure, the weight can be reduced. Since the holes forming the hollow structure serve as an air layer, sound insulation and heat insulation are improved. In addition, since ribs are provided between the holes of the hollow panel, and both ends in the horizontal direction of the hollow panel become thick walls, the rigidity of the hollow panel is improved. Further, the hollow panel manufactured according to the present invention can easily be manufactured having a male engaging portion for joining at one of both ends in the horizontal direction and a female engaging portion for joining at the other. Can be. The hollow panel manufactured according to the present invention can be easily manufactured with a structure in which a cable is embedded in a rib between the holes.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing an example of a hollow panel manufactured by the method for manufacturing a hollow panel of the present invention.
FIG. 2 is a view showing a part of the manufacturing process of the method for manufacturing a hollow panel of the present invention.
FIG. 3 is a view showing a part of the manufacturing process of the method for manufacturing a hollow panel of the present invention.
FIG. 4 is a front view showing another example of the hollow panel manufactured by the method for manufacturing a hollow panel of the present invention.
FIG. 5 is a front view showing another example of the hollow panel manufactured by the method for manufacturing a hollow panel of the present invention.
FIG. 6 is a front view showing another example of the hollow panel manufactured by the method for manufacturing a hollow panel of the present invention.
FIG. 7 is a perspective view showing another example of the hollow panel manufactured by the method for manufacturing a hollow panel of the present invention.
FIG. 8 is a perspective view showing an example of a conventional wood panel.
FIG. 9 is a perspective view showing another example of a conventional wood panel.
FIG. 10 is a perspective view showing another example of a conventional wood panel.
[Explanation of symbols]
10, 20, 30, 40, 50 ... panel, 11, 21, 31 ... holes, 12, 32 ... ribs, 14 ... forming frame, 15, 16 ... forming plate , 17: wood thin piece, 18: core, 22: male locking part, 23: female locking part, 33: cable

Claims (2)

The fiber or wood element to which the binder is attached is laminated together with a plurality of cores, and the laminate is integrally hot-pressed,
A method for manufacturing a hollow panel, wherein the core is drawn out after hot pressing to form a hole having a rib. The method for manufacturing a hollow panel according to claim 1, wherein the wood element is a wood thin piece.

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