JP3163355B2 - Architectural plate and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a building board made of a compressed wood material obtained by heating and compressing a wood material, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Various types of architectural boards such as wall boards, floor boards, ceiling boards, etc. include wood materials, in particular, solid ground boards of wood, or laminated boards, plywood, particle boards, fiber boards, etc. Painted or painted patterns are widely used.

[0003] On the other hand, it is conventionally known to heat and compress wood materials. A conventional compressed wood material is manufactured by humidifying and heating a wood material in a wet state or in a steam atmosphere to a high water content and high temperature state, and then heating and compressing the wood material.

[0004] The above-mentioned prior art is to obtain a compressed wood material by heating and compressing the wood material at a high temperature in a state where a large amount of water is present in the wood material, and to soften wood components such as cellulose, hemicellulose and lignin. In particular, for hemicellulose and lignin, which are non-crystalline components, water largely acts as a plasticizer to lower their softening temperatures to about 60 ° C., respectively, and to perform heat compression while increasing the plasticity of wood. is there.

[0005]

However, especially when softwood is used as the base material, the difference in specific gravity between the spring wood part and the autumn wood part causes a large difference in the amount of paint sucked in, so that the average coating film layer is formed. However, there was a problem that it was not possible to form the color filter, resulting in uneven color.

On the other hand, when hardwood is used as a base material, since the conduit groove is large and porous, bridging of the paint in the conduit groove portion, and conversely, foaming and pinholes caused by the paint falling down. Will occur.

Further, in the case of the prior art in which the wooden material is heated and compressed in a high water content state, the high steam pressure of the water present inside the wooden material is a force for restoring the compressed state when the compression is released. It is difficult to maintain the compressed state in combination with the action and the springback phenomenon due to the decompression.

[0008] Particularly, in the case of a wood material having a low specific gravity,
Although compression is easily performed, puncturing (delamination) may occur due to the instantaneous release of the high vapor pressure of water when the compression is released.

In order to prevent the influence of high steam pressure, cooling may be considered while maintaining the compression and compression state, but this is not practical because productivity is extremely low and cost is greatly increased.

[0010] Further, even if the compressed state can be maintained, the wood material is compressed over the entire wood material in the high water content state, and thus the wood material has a high specific gravity. This means that the volume is reduced by maintaining the compressed state,
This means lower product yields and significantly higher costs.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a new building board and a method for manufacturing the same, which can solve the above-mentioned problems of the prior art.

That is, the building board according to the present invention is made of a compressed wood material having a high specific gravity layer compressed by heating and compression on the front and back surfaces of the wood material whose water content is adjusted to a fiber saturation point or less. A joining means for joining the building boards to each other is provided at a portion of the edge of the base material other than the high specific gravity layer, and a resin layer is provided on at least a surface portion of the high specific gravity layer on the surface thereof. It is characterized in that a colored coating layer and a surface protective layer are sequentially provided on the surface of the layer.

[0013]

Further, in the method for producing a building board according to the present invention, the wood material whose water content has been adjusted to a fiber saturation point or lower is adjusted to a temperature lower than the softening point of cellulose, which is a crystal component of the wood material, and By heating and compressing at a temperature equal to or higher than the softening point temperature of the amorphous component in the adjusted water content, and then decompressing and cooling, a high specific gravity layer is formed on each of the front and back surfaces of the wood material, which is compressed by heating and compression. Then, using the obtained compressed wood material as a base material, a joining means for joining building plates to each other is formed at a portion other than the high specific gravity layer at the edge of the base of the base material, and a resin is applied to at least the high specific gravity layer on the surface. Forming a resin layer on the surface of the high specific gravity layer by applying and curing, forming a colored coating layer by applying a colored coating on the surface of the resin layer,
Further, a transparent coating is applied to the surface of the colored coating layer to form a surface protective layer.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Wood materials include sawn or glued wood, laminated veneer, plywood, particle board, and the like.
A processing material such as a fiberboard is used.

As these wood materials, both softwood materials and hardwood materials can be used, and particularly soft materials and low specific gravity materials are suitably used.

Wood materials have a water content below the fiber saturation point,
Preferably, it is adjusted to 35% or less. For this reason, when a sawn timber is used as a wooden material, it is obtained by drying the timber before sawing and then turning it into a sawn timber or by drying the sawn timber without drying. When a processed material is used, the water content is adjusted to a fiber saturation point or lower during the manufacturing process.

The wood material whose moisture content has been adjusted to be below the fiber saturation point is placed between the hot plates of a hot press equipped with a thickness regulating jig (generally called a distance bar) for regulating the distance between the upper and lower plates. insert.

The thickness regulating jig used between the hot plates at the time of heating and compression has a thickness substantially the same as the thickness of the finally obtained compressed wood material, and the compression ratio of the wood material is 5%. It is preferable that the content is provided so as to be 40%, more preferably 8 to 35%. In other words, a thickness regulating jig having a thickness of 60 to 95%, more preferably 65 to 92% of the thickness of the wooden material is suitably used.

If the compression ratio of the wood material is less than 5%, the compression on both the front and back surfaces becomes insufficient, and the strength required for the high specific gravity layer cannot be obtained. Conversely, the compression ratio is 40%
When the compression ratio exceeds, the compression of both front and back surfaces is performed sufficiently to obtain the necessary strength as a high specific gravity layer, but the overall specific gravity increases, causing weight increase, and reducing the volume by giving an excessive compression ratio That is, it is not preferable because the loss of the raw material increases, the yield decreases, and the cost increases.

The compression ratio of the wood material is within the above range,
It can be arbitrarily selected according to the type of wood, specific gravity, hardness of the front and back surfaces to be obtained, and the like, and a thickness regulating jig is set according to the selected compression ratio.

The pressing time and the pressing pressure are arbitrarily set in accordance with the type of wood material to be used, the tree type, the specific gravity of the wood itself, the softness, etc. In general, the pressing time is 3 to 15 minutes, The pressure is preferably 5 to 25 kg / cm ² .

The hot-pressing of the wooden material in the hot press apparatus is performed by setting the hot-pressing temperature at a temperature not higher than the softening point temperature of cellulose which is a crystalline component of the wooden material and the amorphous component in the water content after the adjustment of the water content. (Hemicellulose, lignin) is performed at a temperature equal to or higher than the softening point temperature.

In the wood material heated and compressed between the upper and lower hot plates of the hot press apparatus, the heat of the hot plate is transmitted to the front and back portions, and the front and back portions undergo thermal softening and compression by the compressive force. Is adjusted to a moisture content below the fiber saturation point, the heat transfer moves into the interior at a relatively slow rate, so that only the front and back portions of the wood are prematurely compressed.

The softening point temperature of cellulose, which is a crystalline component in woody materials, varies slightly depending on the tree species, but is generally about 20%.
The temperature is 0 to 250 ° C., and is substantially constant irrespective of the water content of the wood material. On the other hand, the softening points of hemicellulose and lignin, which are the non-crystalline components of the wood, vary greatly depending on the moisture content of the wood, and the softening points of the hemicellulose and lignin in the dry state are about 180 ° C. and about 150 ° C., respectively. ° C, but both have a softening point of 60 ° C at a water content of 35%, which is the fiber saturation point of wood.
It drops to near. Therefore, in the present invention using a wood material whose water content is adjusted to a fiber saturation point or lower, by hot-pressing at a temperature equal to or higher than the softening point of cellulose, cellulose as a crystalline component is thermally softened, and at the same time, an amorphous component is used. Some hemicellulose and lignin also soften and melt.

After heating and compression as described above, decompression and cooling are performed. As described above, since the temperature of the wooden material itself does not increase as a whole even at the time of hot pressing, it is easily and quickly cooled by the subsequent decompression.

In addition, the hot pressing temperature is not higher than the softening point of cellulose, which is a crystalline component of wood, and not lower than the softening point of non-crystalline components (hemicellulose, lignin) in the water content after the adjustment of the water content. Because it is a temperature, fibrous cellulose remains in the wood tissue of the wood material in a state of compression deformation without thermal softening,
The hemicellulose and lignin softened and melted at the time of hot pressing act as an adhesive to the cellulose, minimizing the springback of the wood material due to decompression after hot pressing, and high specific gravity compressed on both front and back surfaces A layer is formed.

The hardness of the high specific gravity layer on the front and back surfaces of the wooden material is based on JIS
1.5 in the wood hardness test method according to Z-2007
It is preferably at least kgf / mm ² . As a result, the impact resistance of the surface is sufficient and it is hard to be scratched, improving the bending strength of the material itself and improving the dimensional stability as a wood material by reducing the hydrophobicity, swelling rate and water absorption rate Let it. In addition, the numerical value of the hardness by the said test method is measured in the state which each high specific gravity layer was exposed to the outer surface by grinding etc.

In the heat compression of the wood material, in order to improve the smoothness of the high specific gravity layer and to make the thickness of the compressed wood material uniform, the temperature of the wood material is reduced once after hot pressing. It is also possible to adopt a two-stage hot-pressing method in which the material is cooled while it is at a high temperature or to room temperature, and then hot-pressing is performed again.

In the case of performing the two-stage hot pressing, the same thickness regulating jig is used in a hot press apparatus used for the two hot pressing, and the wooden material is spring-backed after the first hot pressing. The returned part can be repressed by the second hot pressing.

Alternatively, in the first hot pressing apparatus, the material is hot-pressed using a thickness regulating jig thicker than the thickness of the wood material to be finally obtained. By using a thickness regulating jig having the same thickness as the thickness of the wood material to be obtained, the return by springback may be suppressed.

Further, if necessary, water may be applied to the surface or the front and back surfaces of the wooden material after the first heat-pressing to adjust the water content of the surface layer, and then the second heat-pressing may be performed. Can be. The surface portion of the wood material becomes absolutely dry by the first heat-pressing. However, by applying water after the first heat-pressing to increase the water content of the surface portion, the wood material can be dried. Plasticity can be imparted to the surface layer to facilitate compression.

The compressed material having the high specific gravity layer compressed by heating and compression on the front and back surfaces of the wooden material in this way is subjected to sanding or the like as necessary to control the thickness, and the building material of the present invention Used as a base material for a plate.

Then, a connecting means for connecting the building boards to each other is formed at a portion of the edge of the base material other than the high specific gravity layer on the front and back sides. The connecting means can be made into a real fruit by the real processing, and is formed at the opposite edges of the base or the four edges of the base.

Since the joining means is formed in the portion of the base material made of the compressed material other than the front and back high specific gravity layers, the cutting work is easy, the damage of the cutting blade is prevented, the wear is small and the life is long. Becomes

A resin is applied to at least the high specific gravity layer on the surface of the substrate on which the bonding means is formed. As the resin to be applied, a resin such as phenol resin, urea resin, melamine resin, epoxy resin, polyurethane resin, vinyl chloride resin, vinyl acetate resin, acrylic resin, fluororesin, alkyd resin, or a modified product thereof alone or in any mixture Used as Further, a paint obtained by using such a resin as a coating film forming element may be used.

The resin applied to the high specific gravity layer is partially impregnated into the high specific gravity layer, and dried and cured by heating or heating and pressing to form a resin impregnated layer. Thereby, the high specific gravity layer is stably fixed, the hydrophobicity of the surface is improved, the swelling rate and the water absorption rate are reduced, the compression rate does not return, and the dimensional stability is improved.

In applying the resin, fine grooves can be formed on the surface of the high specific gravity layer of the compressed material by wire brushing, sanding, or the like, if necessary. By forming fine grooves on the surface of the high specific gravity layer, the impregnation of the resin is promoted by increasing the surface area of the high specific gravity layer, and the adhesion of the resin impregnated layer is improved by its anchoring effect.

Further, a colored paint is applied to the surface of the resin layer and dried to form a colored coating layer. For coloring paints,
A transparent or opaque resin paint such as an amino alkyd resin paint, an acrylic resin paint, a urethane resin paint, a polyester resin paint, etc., which is optionally colored, can be used. Such a colored paint is applied once or arbitrarily multiple times. To form a colored coating layer.

If necessary, the design can be improved by further printing a pattern on the colored coating layer.

Further, a transparent paint was applied on the surface of the colored coating layer.
One coat or any number of multiple coats is applied and dried to form a surface protective layer. As the transparent paint, a resin paint such as an aminoalkyd resin paint, an acrylic resin paint, a urethane resin paint, or a polyester resin paint can be used. A coloring agent is added to the transparent paint as needed. Further, wear-resistant mineral particles such as aluminum oxide, silicon carbide, and silicon oxide may be added and mixed to impart wear resistance to the surface protective layer.

As described above, a compressed wood material in which the high specific gravity layers 2 and 2 compressed by heating and compression are provided on the front and back surfaces of the wood material whose moisture content has been adjusted to the fiber saturation point or less, respectively, is used as a base material. A male nut 6a and a female nut 6b are provided as connecting means for connecting the building boards to each other at a portion of the edge of the base material other than the high specific gravity layer, and at least the surface of the high specific gravity layer on the surface thereof is made of resin. The construction board 1 of the present invention is characterized in that a layer 3 is provided, and further a colored coating layer 4 and a surface protection layer 5 are sequentially provided on the surface of the resin layer (FIG. 1). Needless to say, the resin layer 3, the colored coating layer 4 and the surface protective layer 5 may be formed on the surface layers of the high specific gravity layers 2 on the front and back, respectively.

[0043]

According to the present invention, a high specific gravity layer is formed on each of the front and back surfaces of the wooden material and the center in the thickness direction without increasing the overall specific gravity, so that the bending strength and the surface smoothness are reduced while being lightweight. Thus, an architectural plate free from warpage or twisting can be obtained because the properties and surface hardness are improved and the balance between the front and back is maintained.

The high specific gravity layers formed on the front and back surfaces of the wood material are formed by softening cellulose, which is a crystalline component of the wood material, and compressing after hemicellulose and lignin, which are non-crystalline components, are softened and melted. Because it is formed by hardening, it becomes a hydrophobic film, and combined with the reduction of hydrophilicity by compression, the swelling rate and water absorption rate can be reduced, greatly improving the dimensional stability of wood materials Let it.

Further, by forming the resin layer at least on the surface of the high specific gravity layer on the surface, the high specific gravity layer is stably fixed and the dimensional stability is further improved.

In addition, the design is improved by the colored coating layer formed on the surface of the resin layer, and the hydrophobicity, the swelling ratio and the water absorption are reduced by the surface protective layer.
It suppresses expansion and contraction in the length and thickness directions, and further improves dimensional stability.

Further, in the construction board of the present invention, since the joining means is formed at the edge of the base material except for the high specific gravity layers on the front and back, the cutting blade is not damaged when the joining means is formed. The life is longer because less wear is required.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a schematic configuration of a building plate according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Building material 2 High specific gravity layer 3 Resin layer 4 Color coating layer 5 Surface protective layer 6a, 6b Joining means

Claims (2)

(57) [Claims] 1. A compressed wood material having a high specific gravity layer compressed by heating and compression on the front and back surfaces of a wood material whose moisture content is adjusted to a fiber saturation point or less, and a base of the wood edge. In the portion except for the high specific gravity layer, a coupling means for coupling the building boards is provided, and at least a surface layer of the high specific gravity layer on the surface thereof is provided with a resin layer, and a colored coating layer is formed on the surface of the resin layer. And an architectural plate, which is provided with a surface protective layer in order. 2. A method for softening a non-crystalline component of a wood material having a water content adjusted to a fiber saturation point or less at a softening point temperature of cellulose, which is a crystalline component of the wood material, is equal to or lower than a softening point temperature. By heating and compressing at a temperature equal to or higher than the point temperature, and then decompressing and cooling, a high specific gravity layer compressed by heating and compression is formed on each of the front and back surfaces of the wood, and the obtained compressed wood is used as a base material. And forming a joining means for joining the building boards to each other at a portion of the base edge of the base excluding the high specific gravity layer, applying a resin to at least the high specific gravity layer on the surface thereof, and curing the high specific gravity layer. A resin layer is formed on the surface of the resin layer, a colored coating layer is formed by applying a color coating to the surface of the resin layer, and a transparent coating is further applied to the surface of the colored coating layer to form a surface protective layer. A method for manufacturing a building plate, comprising: