JPH09155817A - Timber for building and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a timber for building which is excellent in bend strength, surface properties, and dimensional stability in spite of its lightness in weight and does not generate warps and torsions by heightening specific gravities of only top and rear faces without heightening the whole specific gravity of a base material so as to form hard layers on the top and rear faces, in a timber formed of a ligneous material as a base material whose surface is coated. SOLUTION: A ligneous material whose water content is adjusted to a fiber saturation point or below is pinched in between hot plates, heated and compressed at a temperature below a softening point temperature of a cellulose as a crystal component of the ligneous material and above a softening point temperature in water content after adjustment of a non-crystal component. Thereafter, the compression is released and cooled, so that a ligneous material having densified hard layers 2 on the top and rear faces of the ligneous material is obtained. With the densified material as a base material 1, a chamfering part 6 is formed at an upper end edge of a butt end. Preferably, on the whole surface of the base material including a decorative layer 4 on the chamfering part and the base material, a surface protective layer 5 is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction material in which a chamfered portion is formed on the surface of a wood material and a method for manufacturing the construction material.

[0002]

2. Description of the Related Art Wall materials, floor boards, ceiling boards, stair treads, stair side boards, shelves, counters, door materials, frame materials, opening members, construction materials and the like are used for various construction materials such as wood materials, particularly wood. Of solid sawed wood or laminated wood, plywood, particle board, etc. What is formed is used.

Further, in order to protect the decorative layer and improve the abrasion resistance of the surface, a coating layer containing an abrasion resistant material is formed on the surface of the decorative layer.

On the other hand, it has been conventionally proposed to heat-compress and consolidate a wood material. Consolidation by heat and compression of the wood material according to the conventional method is performed in a wet state of the wood material, or by humidifying it in a steam atmosphere so that the wood material has a high water content.

In this method, since the compaction is carried out by heating and compressing at a high water content, that is, in the presence of a large amount of water in the wood material, the water is a plasticizer, especially hemicellulose, lignin, etc. in the main components of wood. It has a great effect as a plasticizer on the non-crystalline components of and has a softening point of 60
It lowers the temperature to about 0 ° C and increases the plasticity of the wood material.

[0006]

However, since wood materials used as a substrate for building materials generally have insufficient surface strength and particularly low impact resistance, a coating layer having abrasion resistance has been formed. Even if it was formed on the surface of the decorative layer, scratches and slips were prevented, but scratches such as dents and surface cracks due to impact were likely to occur.

On the other hand, in the consolidation treatment of the wood material by the above-mentioned conventional method, since the wood material is heated and compressed in a high water content state, it is consolidated when the high steam pressure of water present inside the wood material is decompressed. It acts as a force to restore the consolidated state, and it is difficult to maintain the consolidated state together with the springback phenomenon due to decompression. Further, particularly in a wood material having a low specific gravity, the high steam pressure may be released in an instant, so that puncture (delamination) may occur.

In order to prevent the release of the high vapor pressure, it is conceivable to cool in the compressed state, but the productivity is extremely low and the cost is greatly increased.

Further, according to the above-mentioned prior art, even if the compacted state can be maintained, the whole wooden material in the high water content state is compacted, so that it becomes a high specific gravity wooden material. Will end up.

[0010]

SUMMARY OF THE INVENTION The present invention was devised with the object of solving the problems of the above-mentioned prior art, in which hard wood layers, which are compacted on both front and back sides by heat-compressing a wood material, are provided. It is a building material characterized in that a chamfered portion is formed at the upper edge of the mouth of the base material using the compacted material as a base material.

Further, the building material according to the present invention comprises, as a base material, a consolidated material obtained by forming a consolidated hard layer on both front and back surfaces by heat compression of a wood material having a water content adjusted to a fiber saturation point or lower. It is characterized in that a chamfered portion is formed at the upper edge of the wood mouth of the base material.

In these building materials, a surface protective layer may be formed on the entire surface of the base material including the chamfered portion. A decorative layer may be formed on the surface of the base material, and a surface protective layer may be formed on the entire surface of the base material including the chamfered portion.

The surface protective layer may be formed of a wear-resistant surface protective layer mixed with a hard wear resistant material.

The chamfered portion is preferably formed within the thickness range of the hard layer.

In the method for producing a building material according to the present invention, a wood material having a water content adjusted to a fiber saturation point or lower is sandwiched between hot plates, and the temperature is not higher than the softening point temperature of cellulose which is a crystalline component of the wood material. And by heating and compressing at a temperature equal to or higher than the softening point temperature in the adjusted water content of the amorphous component, and then decompressing and cooling, a consolidated material having consolidated hard layers on both front and back surfaces of the wood material. And a chamfered portion is formed at the upper edge of the grain mouth of the consolidated material.

In this method, after forming the fine grooves on the surface of the hard layer of the consolidation material, the chamfered portion can be formed through the adhesive.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The wood material used as the substrate of the building material of the present invention includes solid wood, solid sawn wood, or laminated wood, laminated veneer wood, plywood, particle board, fiber board, and other processed materials. Is used. As these wood materials,
Both softwood materials and hardwood materials can be used, and particularly soft and low specific gravity materials are preferably used.

These wood materials are dried before or after sawing to adjust the water content below the fiber saturation point. The water content below the fiber saturation point here is preferably 35%.
The following water contents are meant.

The wood material whose water content is adjusted below the fiber saturation point is inserted between the hot plates of a hot press machine to which a thickness control jig generally called a distance bar for controlling the distance between the upper and lower hot plates is attached. It

As the thickness controlling jig between the heating plates, a jig having a thickness of 60 to 95%, more preferably 65 to 92% of the thickness of the wood material is used. In other words, the thickness regulating jig is attached so that the compressibility of the wood material is 5 to 40%, more preferably 8 to 35%.

If the compressibility of the wood material is less than 5%, compaction on both the front and back surfaces becomes insufficient, and the strength required for the hard layer cannot be obtained. Conversely, the compressibility of wood is 40
%, The front and back surfaces will be sufficiently consolidated to obtain the required strength as a hard layer, but the overall specific gravity will increase, leading to an increase in weight, and giving an excessive compression rate is a loss of raw material. Is large, the yield is reduced, which causes an increase in cost, which is not preferable.

The compressibility can be arbitrarily selected within the above range according to the species of the wood material used, the specific gravity of the wood itself, the surface hardness to be obtained, etc., and the thickness corresponding to the compressibility. Set the control jig.

The wood material inserted between the upper and lower hot plates of the hot press machine to which the thickness control jig is attached is heated and compressed by hot pressing, and is hardened on both front and back surfaces to form a hard layer.

The hot pressing is carried out at a hot pressing temperature which is equal to or lower than the softening point temperature of cellulose, which is a crystalline component of the wood material, and equal to or higher than the softening point temperature of the amorphous component in the adjusted water content. Be seen.

The pressing time and the pressing pressure are arbitrarily set according to the specific gravity, softness, etc. of the wood material used,
Since the above-mentioned thickness regulating jig is used to obtain the required compression rate during pressing, the pressing time is 3 to 15 minutes and the pressing pressure is 5 to 25 minutes.
It is preferably set to kg / cm ² .

The wood material heated and compressed between the upper and lower heating plates of the hot press machine gradually undergoes thermal softening and consolidation by the pressing force from the front and back surfaces that are in direct contact with the heating plate toward the center. Since the water content is adjusted to a low water content below the fiber saturation point, heat transfer is relatively slow, and only the front and back parts of the wood material are consolidated. In this way, the temperature of the wood material itself does not rise even during hot pressing, so that the wood material is easily cooled by subsequent decompression. Moreover, the fibrous cellulose remains in the wood tissue without being softened by heat, and the softened and melted hemicellulose and lignin act as an adhesive to the cellulose when heated and pressed, so that the solution after hot pressing and pressing Springback of the wood material due to the pressure is minimized, and consolidated hard layers are formed on both front and back surfaces.

The hardness of the hardened layer is JIS Z
-1.5k in the hardness test method of wood according to 2007
It is preferably gf / mm ² or more. Hard layer is 1.
If it is less than 5 kgf / mm ² , the impact resistance of the surface is insufficient and scratches are likely to occur, and since the compaction is insufficient, the bending strength of the material itself is not improved and the material is hydrophobic. Since the swelling rate and the water absorption rate cannot be reduced, dimensional stabilization cannot be achieved.

The thus-obtained compacted material having hard layers on both front and back surfaces is used as a base material, and if necessary, the edge of the wood mouth is subjected to actual processing, and the chamfered portion is formed on the upper edge of the wood mouth. The chamfered portion can be formed within the thickness range of the hard layer on the surface of the base material.

If necessary, a sealer treatment is applied to the entire surface of the base material, including the chamfered portion at the top edge of the base material, and then a surface protective layer is formed. The surface protective layer is formed by applying a synthetic resin coating material such as a transparent or translucent aminoalkyd resin coating material, a urethane resin coating material, an acrylic resin coating material, a polyester resin coating material, etc., which are arbitrarily colored as necessary, and drying.

Abrasion resistant surface protection is obtained by applying and drying a mixture of mineral particles such as alumina and silicon carbide having a particle size of 30 to 200 μm as an abrasion resistant material in this coating material. A layer is formed. Mineral particles mixed in the paint are scattered in the coating layer, either partially exposed on the surface of the wear-resistant surface protective layer to be formed or embedded in the coating layer. doing.

Alternatively, after the decorative layer is formed on the surface of the base material, the surface protective layer as described above may be formed on the entire surface including the chamfered portion of the upper edge of the mouth of the base material. The decorative layer is, if necessary, subjected to a base treatment such as a sealing treatment or a sealer treatment on the surface of the base material, and then subjected to, for example, colored coating or pattern pattern printing, or a decorative veneer, a decorative paper, or an adhesive. It is formed by sticking a decorative material such as a decorative synthetic resin sheet.

If necessary, fine grooves can be formed in the surface hard layer of the substrate by wire brushing, sanding or the like. The fine grooves increase the surface area of the hard layer, and the anchoring effect due to it increases, so
To improve the adhesive force of the decorative material provided on the surface of the hard layer.

The softening point temperature of cellulose, which is a crystalline component in wood, is 200 to 25 regardless of the water content of wood.
Although it is almost constant at 0 ° C, the softening point temperatures of non-crystalline components, hemicellulose and lignin, vary greatly depending on the water content of wood, and the softening point temperatures of hemicellulose and lignin in an absolutely dry state are about 180 ° C, respectively. About 150 ℃
However, at a water content of 35%, which is the fiber saturation point of wood, the softening point temperature decreases to around 60 ° C.
That is, unlike cellulose, which is substantially non-plastic, hemicellulose and lignin are plasticized by the water contained in the wood material acting as a plasticizer even at a fiber saturation point or lower.

Therefore, for example, the fiber saturation point of 3
In the case of the wood material adjusted to have a water content of 5%, the heat-pressing temperature in the range of about 60 to about 200 ° C. causes the cellulose, which is a crystalline component, to be hardly softened and to be amorphous in the tissue cells. The components hemicellulose and lignin can be heat-softened.

By heating and compressing a wood material having a low water content below the fiber saturation point at such a temperature, only the portions near the front and back of the wood material are consolidated to form a hard layer.

A chamfered portion is formed on the upper edge of the opening of the base material to obtain the building material of the present invention.

FIG. 1 shows a schematic structure of a building material according to the present invention, in which hard layers 2 and 2 by consolidation are formed on both front and back surfaces of a wood material which is a base material 1, and a decorative layer 4 is formed on one surface thereof. Further, a wear-resistant surface protective layer 5 is formed on the surface of the decorative layer 4 without hiding the decorative layer 4. The chamfered portions 6, 6 are formed on the upper edge of the opening of the base material 1 within the thickness range of the hard layer 2.

As an example of the substrate 1, a thickness of 30 mm,
Width 150 mm, length 100 mm, overall specific gravity of about 0.5 solid Agatisu sawwood, low water content below the fiber saturation point (19 ~
21%) and then inserted between the hot plates of a hot press machine equipped with a thickness control jig of 25 mm, the hot plate temperature of 160 ° C., the pressing pressure of 20 kgf / cm ² , and the pressing time of 5 minutes. After heating and pressing at 25m, the obtained thickness is 25m.
Hard layers 2 and 2 having a specific gravity of 0.6 to 1.0 are formed in the thickness range of about 4 to 5 mm from the front and back surfaces of the compressed solid wood of m, respectively, and the specific gravity of the inner central portion 3 thereof is before the consolidation treatment. The overall specific gravity of (about 0.5) was almost constant. Also,
The hardness of the hard layer is 1.5 to 3.6 kgf / mm ² ,
The hardness was remarkably improved as compared with the material hardness before the consolidation treatment of 0.8 to 1.1 kgf / mm ² .

[0039]

According to the present invention, the hard layer is formed by increasing the specific gravity of only the front and back of the wood material without increasing the overall specific gravity.
Since the surface hardness is improved and the balance between the front and back is maintained, even if a chamfered part, a decorative layer, a surface protective layer, etc. are formed on only one surface, warpage or twisting occurs. Never.

The hard layer having excellent surface strength prevents scratches such as dents and surface cracks due to impact, and further,
By forming a wear-resistant surface protective layer on the surface, scratches and slips are prevented, and thus a building board having extremely excellent surface abrasion resistance can be obtained.

The hard layers on the front and back of the wood material as the base material are mainly hemicellulose, which is an amorphous component in the wood material,
Since lignin is formed by being softened and melted once and then hardened to a high density that is compressed, it becomes a hydrophobic film and reduces the swelling rate and water absorption rate together with the decrease in hydrophilicity due to consolidation. It is possible to greatly improve the dimensional stability of the wood material.

[Brief description of the drawings]

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material 2 Hard layer 3 Central part 4 Decorative layer 5 Abrasion resistant surface protective layer 6 Chamfered part

Claims (8)

[Claims] 1. A chamfered portion is formed at an upper edge of a wood mouth of a base material of a consolidation material having hard layers which are compacted on both front and back sides by heat-compressing a wood material. Building materials to be used. 2. A compacted material having a consolidated hardened layer formed on both front and back surfaces by heat-compressing a wood material having a water content adjusted to a fiber saturation point or lower, and using the compacted material as a base material, the upper edge of the mouth of the base material. A construction material characterized in that a chamfered portion is formed on the. 3. The building material according to claim 1, wherein a surface protective layer is formed on the entire surface of the base material including the chamfered portion. 4. A decorative layer is formed on the surface of the base material,
The building material according to claim 1 or 2, wherein a surface protective layer is formed on the entire surface of the base material including the chamfered portion. 5. The building material according to claim 3, wherein the surface protective layer comprises a wear-resistant surface protective layer mixed with a hard wear-resistant material. 6. The chamfered portion is formed within the thickness range of the hard layer.
One of the building materials. 7. A water content of a wood material whose water content has been adjusted to a fiber saturation point or less is sandwiched between hot plates so as to be below the softening point temperature of cellulose, which is a crystalline component of the wood material, and which is an amorphous component after the adjustment. Heat compression at a temperature above the softening point temperature, then decompressing and cooling to obtain a consolidated material having consolidated hard layers on both front and back surfaces of the wood material, and the upper end of the mouth of the consolidated material. A method for manufacturing a building material, which comprises forming a chamfered portion on an edge. 8. The method for manufacturing a building material according to claim 7, wherein the chamfered portion is formed via the adhesive after forming fine grooves on the surface of the hard layer of the consolidated material.