JP5561958B2 - Wood-based composite materials and their uses - Google Patents

Description

  The present invention relates to a wood-based composite material and its use, and more particularly to a wood-based composite material that is excellent in impact resistance, hardly causes abnormalities such as cracking and breakage, and hardly deforms, and its use.

  Conventionally, in order to recycle wood waste materials such as building demolition materials, the wood waste pieces are obtained by chipping the waste materials into chips or the like, and a binder such as an adhesive, and the wood pieces are oriented in the longitudinal direction. A wood-based composite material is known in which the wood pieces are compressed in the vertical direction with respect to the longitudinal direction and the wood material pieces are bonded together by a binder (see Patent Document 1). Depending on the material and shape of the wood pieces, this material has a problem that it is difficult to exhibit a desired strength and is inferior in impact resistance.

Japanese Patent No. 3520077

  Under such circumstances, an object of the present invention is to provide a wood-based composite material that is excellent in impact resistance, hardly causes abnormalities such as cracks and breaks, and is difficult to deform.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have combined a wood-based composite material that contributes to solving the above-mentioned problems by combining a specific material as an elongated wood piece in the wood-based composite material as described above. And the present invention has been made based on this finding.

That is, according to the first invention of the present invention, it is made of a material including a wood material piece containing at least 10% by weight of an elongated wood piece of cedar and cypress, an elongated demolished wood piece, and a binder, longitudinally compressing the wood material pieces that the stacking direction stacked while being substantially oriented, is heated, Ri Na are bonded to each other woody material piece by the binding agent, the cedar and cypress raw material der Rukoto A wood-based composite material is provided.

  According to a second invention of the present invention, there is provided a wood-based composite material according to the first invention, wherein the compression is performed so that the cross-sectional area of the wood material pieces is 70% or less on average. Is done.

According to the third invention of the present invention, there is provided a woody composite material according to the first or second invention, wherein the cedar and / or cypress is a thinning material.

Moreover, according to the 4th invention of this invention, the structural material which uses the wood type composite material in any one of 1-3 is provided.

Moreover, according to the 5th invention of this invention, the semi-structure material which uses the wood type composite material in any one of 1-3 is provided.

Moreover, according to the 6th invention of this invention, the construction material which uses the wood type composite material in any one of 1-3 is provided.

Moreover, according to 7th invention of this invention, the structure core material formed using the wood type composite material in any one of 1-3 is provided.

Moreover, according to the 8th invention of this invention, the face material formed using the wood type composite material in any one of 1-3 is provided.

According to the ninth aspect of the present invention, there is provided a shaft assembly using any one of the first to third wood-based composite materials.

According to a tenth aspect of the present invention, there is provided a wooden shaft using any one of the first to third wood-based composite materials.

According to the eleventh aspect of the present invention, there is provided a wall core material using any one of the first to third wood-based composite materials.

  According to the wood-based composite material of the present invention, it is excellent in impact resistance, hardly causes abnormalities such as cracks and breaks, is not easily deformed, and even if some wood fragments derived from building demolition materials are used as raw materials, There is an advantage that the desired effect can be satisfied to some extent and the cost can be reduced as a whole.

The wood-based composite material of the present invention comprises a wood material piece containing an elongated wood piece of a predetermined material and a material containing a binder, and the wood material pieces stacked in a substantially oriented state in the longitudinal direction. It is characterized in that it is compressed and heated in a direction perpendicular to the direction, and the wood material pieces are bonded together by a binder.
As a raw material material that becomes a wood material piece, it is preferable to use a combination of cedar and cypress, and the form that can be used for the raw material is not particularly limited. For example, logs of the above tree species, thinned wood And other raw materials, scraps generated at factories and residential construction sites, and waste pallet materials discarded after transportation.
The wood material piece preferably contains at least 10% by weight of the cedar and cypress wood pieces, particularly 30% by weight or more, especially those whose tree species consists only of cedar and cypress, and other wood pieces are not particularly limited, Wood fragments from building demolition materials can also be used.
The content ratio of the cedar wood pieces and the cypress wood pieces in the wood material pieces is preferably in the range of 10:90 to 90:10 on a mass basis.
Moreover, it is preferable that cedar and / or cypress is thinned wood, and it is particularly preferable that both cedar and cypress are thinned wood.

  The processing method to make the above-mentioned raw material into a piece of wood material is a method of cutting a veneer processed with a rotary cutter into a chopsticks shape to make a stick, a method of cutting a log into a strand with a rotary blade of a flaker, a uniaxial crushing A method of crushing wood by rotating a roll with a blade on the surface of the machine can be used. The crusher includes a machine generally called a crusher. In addition, it is possible to use a small piece manufacturing machine with cutting as the element generally used for particle board, but the small piece is thinly cut and the strength is comparatively difficult, crushing with crushing as an element The crushed pieces such as crushed chips produced by a machine have a long and thin shape such as a spindle shape and are easy to obtain strength, and this is more preferable.

  When the crushed wood material pieces are uneven in thickness, they are classified into wood material pieces having a certain range of thickness. The classification method is not particularly limited as long as it can be classified with a certain range of thickness. For example, a classification method using a classifier such as a wave roller method may be used. The wave roller type classifier is a device that performs continuous classification based on the thickness of the chip.

In the wood-based composite material of the present invention, the wood material piece used has a specific gravity of 0.3 to 0.6, a length of 20 mm to 150 mm, and a thickness (short side) of 1 mm to 11 mm. Preferably there is.
If the specific gravity of the wood material piece is less than 0.3, sufficient strength cannot be obtained due to the decay of wood, etc., or sufficient compaction processing cannot be performed during molding, and sufficient strength is achieved. If it is not obtained or exceeds 0.6, the wood material piece is hard, and it becomes difficult to form a desired structural material or the like.

If the thickness of the wood material piece is less than 1 mm, the constituent material piece becomes too small, a large amount of binder is required, and sufficient strength is not exhibited. If the thickness exceeds 11 mm, the thickness of the wood-based composite material The number of wooden pieces stacked in the vertical direction is reduced, stress transmission is not performed sufficiently, stress concentration is likely to occur at the joints of the wooden pieces, and sufficient strength is difficult to obtain.
Further, when the length of the wood material piece is less than 20 mm, when used as a structural material or the like, the strength in the axial direction becomes insufficient, and when it exceeds 150 mm, when the wood material pieces are laminated, 1 The crossing points of the wood material pieces of the book increase, and it becomes difficult to consolidate sufficiently.
In addition, since the wood material piece cannot be completely separated with respect to its length, it is sufficiently effective if a material having a predetermined length is contained in a weight ratio of 70% or more, preferably 80% or more. Is demonstrated.

  Moreover, the ratio between the length and the thickness of the wooden material piece is not particularly limited, but the length is preferably 10 times or more of the thickness. If the length is less than 10 times the thickness, the strength in the axial direction of the wood-based composite material may be insufficient.

  The wood material piece preferably has a constant moisture content. By making the moisture content constant, the quality variation of the wood-based composite material during production is eliminated. A preferable moisture content is 0 to 10%. As a method for keeping the moisture content constant, for example, there is a method of leaving a piece of wood material for a certain time in a temperature-controlled oven. Incidentally, when left in an oven at 50 ° C. for 24 hours, the water content is maintained at about 5%.

  The woody composite material of the present invention preferably has a bulk density of 0.6 or more. When the bulk density is less than 0.6, sufficient bonding of the wood material pieces cannot be obtained, and there is a possibility that sufficient strength cannot be obtained when used as a structural material. Further, the porosity is not particularly limited, but is preferably 10% or less. If the porosity exceeds 10%, the wood material pieces in the wood composite material are not sufficiently bonded to each other, and there is a possibility that sufficient strength may not be exhibited.

Examples of the binder used in the present invention include thermosetting resins such as phenol resins, urea resins, melamine resins, isocyanate resins, vinyl acetate resins, thermoplastic resin-based adhesives, natural components, and natural products. Examples include wood industry adhesives used for plywood, particle boards, and the like, such as natural product-derived adhesives obtained by purification, extraction, modification, and the like.
Specific examples of adhesives derived from natural products include gelatin, casein glue, soybean glue, glue, protein adhesives such as albumin, starch, dextrin, rice glue, starch adhesives such as glucomannan, chitin Examples include animal-based adhesives such as chitosan, cellulose-based adhesives, lignin-based adhesives, and tannin-based adhesives.
These binders may be used individually by 1 type, or may use multiple types together.
The binder may be in liquid or powder form, but in the case of liquid, it is generally sprayed onto the wood material piece or stirred and mixed with the wood material piece and supplied to the forming type in a state of being supported on the wood material piece in advance. In the case of powder, it is generally supplied to the forming mold in a state of being uniformly mixed with the wood material piece.
In particular, a tannin-based adhesive is preferable because it is an extracted component from natural wood, has good affinity with a piece of wood material, has moderate tackiness, and further becomes high strength when cured. Tannin-based adhesives may be cured by heating or the like using tannin alone, but in applications where durability is required, it is preferable to use a crosslinking agent such as an aldehyde compound, an isocyanate compound, or an epoxy compound in combination. . The tree species from which the tannin-based adhesive is extracted is not particularly limited, but those extracted from radiata pine, black wattle, mimosa, quebracho, and chestnut are preferred. When the tannin extracted from wood is solid, it can be used by dissolving or dispersing in water or an organic solvent as necessary.
The binder is preferably used in a range of 1 to 20% on a mass basis with respect to the wood material piece. If the amount of this binder is too small, the adhesion will be insufficient, and if it is too large, the adhesive performance will not improve for the increased material cost, and the appearance and nailing performance will deteriorate, the appearance will not be woody There are problems such as.

  As a method of putting the wood material with a binder obtained as described above into a forming mold, a disk orienter used in an existing wood-based molding material manufacturing apparatus such as an oriented strand board (OSB). It is possible to use a method in which a known orientation means such as the above is disposed above the forming type and placed while being oriented by this orientation means. However, a wood material piece with a binder is introduced from the upper input port to the slit-shaped discharge port. A method in which a hopper having an inner surface-shaped (bowl-shaped) orientation portion whose width decreases toward the top of the forming mold so that the discharge port faces the upper opening of each divided frame portion and is inserted through the hopper It is preferable to use it. In addition, it is possible to use a method in which ridges are arranged side by side in the width direction so as to form a concavo-convex groove shape and flow through the groove.

  In other words, by using the hopper as described above, it is possible to efficiently supply the wood material piece with the binder to each forming-type divided frame portion, that is, without loss. The inner surface shape of the hopper is determined by the forming type shape, but may be any shape as long as the wood material piece with the binder is not clogged. Specifically, it is preferable that the slit width of the discharge port is 15 mm or more and smaller than the inner width of the divided frame portion.

  The shape of the forming type is appropriately determined depending on the wood-based composite material to be obtained. For example, when obtaining a plate-shaped wood-based composite material of 1000 × 500 × 30 mm, the forming type is about 1000 × 500 × 100 mm. It is preferable to form a laminated mat. That is, the vertical and horizontal dimensions of the laminated mat are made the same as or slightly larger than the vertical and horizontal dimensions of the wood-based composite material to be obtained, and the thickness of the laminated mat is at least obtained. The thickness is preferably three times or more that of the composite material.

  In addition, the method for forming the divided frame portions at a constant interval in the forming type is not particularly specified, but the frame-like composite material to be obtained has the same size as the vertical and horizontal dimensions or a slightly larger frame shape. It is sufficient to partition the inside of the mold body with a metal plate having a thickness of several mm. The direction of division is determined by the required molded product because the strength characteristics are different between the direction in which the wood material pieces are oriented and the direction perpendicular to the orientation. By the way, in the case of obtaining the above-mentioned 1000 × 500 × 30 mm plate-like wood-based composite material, 19 partition plates with a height of 100 mm are used in the forming body with a frame shape of 1000 × 500 × 100 mm. Thus, it is preferable to use a forming type in which the width direction (500 mm side) is partitioned at a constant interval of 20 mm. Moreover, the partition plate may be fixed to the forming type main body, or may be detachable.

  Further, there is a more preferable relationship between the thickness of the wood material piece and the inner width of the divided frame portion in order to obtain a high-strength wood composite material. For example, when the thickness of the wood material piece is 1 mm to 11 mm, forming The inner width of the divided frame portion of the mold is preferably 20 mm to 40 mm. When the thickness of the wood material piece is 3 mm to 5 mm, the inner width of the forming-type divided frame portion is preferably 20 mm to 30 mm. .

  In other words, if the inner width of the divided frame portion is too narrow, the wooden material pieces will not fall cleanly in the divided frame portion, which is likely to cause trouble when automatically producing, and if the inner width of the divided frame portion is too wide, It may become difficult to align and the required strength in the alignment direction may not be achieved. The mat made of wooden material pieces oriented in the forming type is thrown into a press machine that can be pressurized and heated with the entire forming type removed or only the partition plate that leaves the forming type main body removed. If the laminated state of the wooden material pieces collapses when the partition plate or forming mold is removed, it is possible to place a collapse prevention sheet in the forming mold in advance and press-mold the entire sheet. It is. That is, for example, newspaper may be laid in a forming mold as a collapse preventing sheet, and when removing the forming mold, the mat may be wrapped with newspaper and press-molded in a state of being fixed with a string or adhesive tape.

  Although it does not specifically limit about compression, Usually, it performs by the mechanical pressurization by a press, for example, hydraulic pressure etc. For example, in the case of a press machine, a vertical press machine or a continuous press machine for forming an existing woody material can be used in a vertical direction. As for the temperature conditions of a press, the range of 100-250 degreeC is preferable normally. The pressure condition is preferably in the range of 1 to 10 MPa. The press time may be a time for the binder to cure. If it is less than 1 MPa, it cannot be compressed sufficiently, and if it exceeds 10 MPa, the equipment for pressing becomes expensive. The pressing time may be applied by heating and pressure for a time during which the binder is cured.

  Usually, the heating is preferably in the range of 100 to 250 ° C. The heating method is not particularly limited, but for example, there is a method of transferring heat from the surface of a wooden material piece to the inside by heat transfer like a hot plate, or a method of directly heating the inside such as steam injection or high frequency heating. Can be mentioned. Heating and pressurization may be performed simultaneously, may be performed after pressurization, or may be performed after heating. When heating with steam, the steam is injected at a pressure of 0.05 to 2 MPa. If the pressure is less than 0.05 MPa, the wood material piece is not softened and cannot be compressed, and if it exceeds 2 MPa, the equipment is too large and is not realistic.

  Furthermore, when producing the woody composite material of the present invention, it is preferable to perform annealing, cutting, and sanding processing after press molding in order to improve the dimensional accuracy and surface properties of the woody composite material obtained.

As the woody composite material of the present invention, preferably, a large number of cedars having a weight ratio of 70% or more in a range of density 0.3 to 0.6 g / cm ³ , thickness 1 to 11 mm, and length 20 to 150 mm A material containing cypress wood material pieces and a binder for bonding these wood material pieces are stacked in a state where the length directions of the wood material pieces are oriented in substantially the same direction, and heated and stacked. It is preferably a composite material having a bulk density of 0.6 g / cm ³ or more obtained by compressing in the direction and bonding the pieces of wood material.
In the wood-based composite material, it is further preferable that the thickness direction is a direction perpendicular to the orientation direction of the wood material piece and the compression direction.

  The wood-based composite material of the present invention is used for various applications, for example, structural materials such as columns, beams, and foundations, studs (wall core materials), joists, trunk edges, large draws, rafters, field edges, and the like. Construction materials such as structural materials, joinery, stairs, frames, fences, construction core materials (core materials for construction materials), floor materials, wall materials, face materials such as ceiling materials (sometimes referred to as surface materials), etc. It is suitably used for shaft assemblies, wooden shafts, wall core materials, and the like.

Since the studs using the wood-based material of the present invention are installed so that the direction perpendicular to the longitudinal direction and the compression direction are perpendicular to the wall surface, the joint is good and the holding power of the joint is large, Since the expansion due to moisture absorption is small, the wall surface material can be firmly fixed, and the influence of the expansion of the studs due to the increase of the moisture in the wall on the wall surface is small, and a stable wall surface can be maintained.
When used as joists, the vertical direction is the direction perpendicular to the longitudinal direction and the compression direction, and the wood material is more evenly arranged in the vertical direction than in the horizontal direction. Since the holding power of the coupler is large and the expansion due to moisture absorption is small, deformation due to moisture from below the floor is small, and large flooring and a floor assembly having a large coupling force with the floor base material and the flooring material can be formed.
When using as a ceiling edge or a field edge receiver, it is preferable to set the vertical direction to the longitudinal direction and the compression direction, respectively, but since there is less influence of moisture compared to the floor, each in the longitudinal direction and the compression direction. The vertical direction may be the horizontal direction.
When used as a joinery core material, it may be used in the same direction as the stud.
The reason why the expansion due to moisture absorption differs between the compression direction and the direction perpendicular thereto is that the compact is consolidated in the compression direction of the molded body, and the wood fibers constituting the wood material piece are also crushed in the compression direction. Therefore, when moisture enters the molded body, a part of the crushed wood fiber is recovered, and the expansion in the compression direction is increased. Therefore, expansion in the direction perpendicular to the compression direction is reduced.

  Hereinafter, the present invention will be described in detail by way of examples and comparative examples, but the present invention is not limited to these examples.

Example 1-2, Comparative Example 1-3 (Shock strength test of surface wall panel)
A surface wall panel having a wood axis of the wood material of the present invention and a control wood material for comparison as a wood axis was prepared as described below, and the following impact strength test and deformation resistance performance test were performed.
(1) Specimen The following wooden shaft and gypsum board were assembled by joining with a vinyl acetate adhesive and fixing with a tucker to form a surface wall panel.
Wood axis: Various wood materials with different types of wood chips, produced as follows: Mixture of 100 parts by weight of slenderly crushed wood chips and 7 parts by weight of binder (isocyanate adhesive) Are stacked with the wood chips oriented substantially in the longitudinal direction, and the wood chips are flattened in a direction perpendicular to the longitudinal direction to compress the cross-sectional area of the wood material pieces, and the wood material pieces are bonded to each other by a binder. (Density: 0.6-0.7 g / cm < ² >).
Gypsum board: length 2,310 or 2,670 mm, width 910 mm, thickness 9.5 mm
(2) Test method: (See “Interior Wall Unit” BLT WU-02: 2005 ”)
The impact strength test was conducted with reference to the Better Living excellent housing part performance test method, and the evaluation was performed by visual inspection and measurement of residual deformation.
Fix the top and bottom of the test specimen (surface wall panel) and almost the center in the height direction with the upper and lower ends of a rectangular wooden frame built in a unit frame constructed of steel frames and horizontal rails attached to the left and right sides. A 15kg sand bag hung with a string on a wooden shaft approximately 1/4 from the lower side of the panel height so that the distance from the suspension source to the center of gravity is 1000 mm, naturally falls from an angle of 45 ° I was shocked.
This was repeated, and the presence or absence of abnormalities such as cracks and breaks was confirmed and the amount of deformation was measured.
According to the BL standard of the partition wall, there is no abnormality such as cracking or breaking even after the impact is repeated five times, and the displacement amount due to deformation is 1/120 or less of the height. The presence or absence of abnormality such as breakage was evaluated according to the following criteria.
s: Japanese cedar (100%)
h: Cypress (100%)
k: Demolition material (100%)
s / h: Japanese cedar (50%) / Japanese cypress (50%)
s / h / k: Japanese cedar (25%) / Japanese cypress (25%) / Dismantling material (50%)
Japanese cedar and Japanese cypress are thinned wood from Wakayama Prefecture.
A: No cracks or breaks up to the 10th time O: No cracks or breaks up to the 5th time X: Cracks or breaks up to the 5th time Table 1 shows the results.

Example 3-4 (Ceiling Loading Test)
A ceiling (shaft panel) using the wood material of the present invention and a comparative wood material for comparison as a wood axis was prepared as follows, and the following deformation resistance performance test was performed.
(1) Specimen The following wooden shaft and gypsum board were assembled by joining with a vinyl acetate adhesive and fixing with a tacker to form a ceiling (shaft panel).
Wood axis: Various wood materials with different types of wood chips, which are made of wood-based composite materials produced as follows.
An admixture of 100 parts by weight of a slenderly crushed wood chip and 7 parts by weight of a binder (isocyanate-based adhesive) is laminated with the wood chip substantially oriented in the longitudinal direction, and the wood chip is perpendicular to the longitudinal direction. It is flattened in the direction to compress the cross-sectional area of the wood material pieces, and the wood material pieces are bonded to each other by a binder.
There are two types of field edges: length 2750 mm, width 40 mm, thickness 27 mm, width 30 mm, and thickness 20 mm. The size of the edge receiver is 1845 mm in length, 40 mm in width, 27 mm in thickness, and 910 mm in pitch.
The dimension of the ceiling is 2730 mm × 1820 mm.
Gypsum board: length 1820mm, width 910mm, thickness 9.5mm
<Test method>
A hooked screw (screw length = 35 mm) is attached to the center edge of the ceiling shaft (panel) that supports the specimen (ceiling shaft panel) with four hanging bundles (27 mm x 40 mm). The suspended metal fitting hung on the tip is loaded as follows, and the displacement is measured in units of 0.01 mm with a dial gauge.
Loading point and measuring point Loading is performed on the central edge of the ceiling shaft supported by four hanging bundles. The displacement measurement point is the intersection of the loading point and the field edge to be loaded and the field edge supporting the field edge.
1. Strength test The load after loading is sequentially changed to 98 N (10 kgf), 196 N (20 kgf), and 245 N (25 kgf), and the displacement after loading is measured.
2. Deformation performance test over time A load of 147N (15 kgf) is loaded, and the displacement immediately after loading, 1 day, 3 days, 5 days, 7 days, and 14 days after is measured.
The results are shown in Tables 2 and 3.

ｓ／ｈ／ｋ：スギ（２５％）／ヒノキ（２５％）／解体材（５０％）
スギ、ヒノキは和歌山県産間伐材
解体材は建築解体材（ユキ工業社製）
これらの試験において、本発明の木質系材料を用いてなる野縁は、良好とされる変位量４．５ｍｍ以下の評価基準をクリアーした。

s / h / k: Japanese cedar (25%) / Japanese cypress (25%) / Dismantling material (50%)
Japanese cedar and Japanese cypress are thinned from Wakayama Prefecture. Demolition is demolition from construction (manufactured by Yuki Kogyo)
In these tests, the field edge using the wood-based material of the present invention cleared the evaluation standard of a displacement amount of 4.5 mm or less, which is regarded as good.

  The wood-based composite material of the present invention is excellent in impact resistance, is unlikely to cause abnormalities such as cracks and breaks, is not easily deformed, and is expected even if some wood fragments derived from building demolition materials are used as raw materials. Can be satisfied to some extent and the overall cost can be reduced, so structural materials such as columns, beams, and foundations, studs (wall core materials), joists, trunk edges, large draws, rafters, field edges, Construction materials such as joinery, staircases, frames, fences, construction core materials (core materials for construction materials), floor materials, wall materials, ceiling materials (surface) surface materials, shaft assemblies, wooden shafts, wall core materials, etc. Can be suitably used in the present invention, and is very useful industrially.

Claims (11)

  A wood material comprising a wood material piece containing at least 10% by weight of a wood piece of cedar and cypress and a wood material piece containing an elongated dismantled wood piece, and a binder, and stacked in a substantially oriented state in the longitudinal direction. A wood-based composite material, wherein the material pieces are compressed and heated in the stacking direction, and the wood material pieces are joined together by a binder, and the cedar and cypress are raw materials.   2. The wood-based composite material according to claim 1, wherein the compression is performed so that the cross-sectional area of the wood material pieces is 70% or less on average. The woody composite material according to claim 1 or 2 , wherein the cedar and / or cypress are thinned wood. A structural material using the woody composite material according to any one of claims 1 to 3 . A semi-structured material using the woody composite material according to any one of claims 1 to 3 . Artificial material made from the woody composite material according to any one of claims 1 to 3 . An artificial core material using the woody composite material according to any one of claims 1 to 3 . Surface material made using wood-based composite material according to any one of claims 1-3. Framing material made using wood-based composite material according to any one of claims 1-3. Wood shaft material made using wood-based composite material according to any one of claims 1-3. The wall core material using the wood type composite material in any one of Claims 1-3 .