JPH07214506A - Densified plywood and its production - Google Patents

Abstract

PURPOSE:To easily produce plywood for building such as a floor board as platelike plywood having high strength, ultrahigh modulus of elasticity and toughness by putting fiber reinforcement giving strengthening between veneers to be laminated and laminating them through an adhesive to produce plywood. CONSTITUTION:Fiber reinforcement 2 giving strengthening such as glass fiber giving strengthening is interposed in an adhesive layer 3 between a first layer and a second layer of ligneous veneer. Strength in the direction of fiber is obtained regardless of the surface and the rear. The adhesive layer 3 of base material is formed of phenol resin in which adhesive strength to veneer is strong. Adhesion is made sure by phenol resin and the reinforcement 2 specially impregnated with phenol resin. Combination of the adhesive and the reinforcement 2 is strengthened by adding a silane coupling agent to phenol resin. High modulus of elasticity and high strength are supplied through high functionality given by the reinforcement 2. Building material such as a floor board is easily produced which has high strength, high modulus of elasticity and toughness of densified plywood.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a plywood composed of a fibrous wood veneer used as a structural material for construction, which has super high strength, super high elastic modulus and toughness. Along with it, it relates to a reinforced plywood with improved anisotropy. Particularly, relating to a plate-like plywood that can be used for flooring, roofing, wall materials, etc. or for construction work, a method of reinforcing a plywood by bonding a plurality of fibrous wood veneer and a reinforcing material with an adhesive, and thus obtained Reinforced plywood.

According to the present invention, a reinforcing material having a high tensile strength and a large elastic modulus is used, and by devising a method of integrating this with plywood, the disadvantage of conventional plywood, which is anisotropy, can be overcome. It is possible to improve the performance. According to the present invention, it is possible to provide a highly functional material having higher strength, higher elastic modulus, toughness, and no anisotropy than conventional plywood.

[0003]

2. Description of the Related Art Plywood is mainly used as an important structural material for construction. Plywood is used as floor material, roof material, wall material, etc. In recent construction work, weirs for concrete formwork are
Plywood made by stacking thinly peeled wooden boards and adhering them is used. For this reason, it is required to have a property that is strong against bending tensile force when used as a mold, is hard and has a small bending deformation, but still has sufficient strength and elastic modulus in both long and short directions of plywood. The one with has not been obtained.

Ordinary plywood is made of raw wood such as lauan and coniferous wood.
It is made by slicing into a thin plate (hereinafter referred to as a single plate) of ~ 3 mm and pasting it with an adhesive. However, the use of plywood for formwork, which is made from raw wood of tropical forests such as Lauan, is being severely reviewed from the viewpoint of forest protection and ecosystem protection. Furthermore, plywood laminated with thinly peeled raw wood is a resource-related problem, while further reducing the consumption of raw materials,
Although it is required to easily and inexpensively obtain a material having higher strength and good elastic modulus and having no difference in performance depending on directions, it is not yet in a satisfactory situation. If the thickness of the veneer is extremely thin up to about 0.1 to 1 mm, it is difficult to obtain sufficient strength.

Generally, a melamine resin, a phenol resin, or the like is used as an adhesive for attaching the single plates.
Pressed at high temperature and high pressure to make a plywood board. By the way, in a veneer that constitutes plywood, wood fibers are continuous in only one direction. This fiber direction has a problem of being strong in tension and hard (having a large elastic modulus), but extremely weak in the direction perpendicular to the fiber. That is, plywood has anisotropic properties. For this reason, when laminating the single plates, the fiber directions of the trees are made orthogonal to each other so that the degree of anisotropy of performance is reduced. Further, by bonding a plurality of single plates, the overall thickness is increased and strengthened.

At present, plywood is made by laminating odd number of veneer.
It's a board. By using an odd number of sheets, the fiber directions of the single plates on the front and back of the board are the same. This is to provide a board having the same performance without distinction between the front and the back, and to facilitate the usability for the user. If an even number of veneers are attached to form a board, the performance of the board will differ depending on how the front and back sides are used, causing confusion for the user.

[0007] For the veneer on the front and back of the board, a young tree sliced from the part close to the skin side of the raw tree is used, and for the veneer of the board core, sliced from the part close to the core of the raw tree. Old wood is used. This is because you try to use the wood without waste and when the bending force acts, the closer you are to the surface of the board, the greater the pulling force that acts, so try to place a young and strong veneer in this part. It is a thing. In this way, there is a difference in performance between the young tree and the old tree, and even if the same tree is used, an odd number of veneers with anisotropy in performance are pasted together, so the performance characteristics of the entire plywood are yet,
Anisotropy remains. The strength in the direction orthogonal to the fiber direction is only about 0.6 to 0.7, where the strength in the case of being pulled in the fiber direction visible on the surface of the plywood is 1. The elastic modulus is also the same.

On the other hand, a large force of ³ to 5 tf / m ² is applied to the mold used for preventing outflow when concrete is poured. For this reason, when plywood is used as a structural structural material that receives a force, such as a formwork material, a major problem is whether the surface of the plywood is subjected to bending or pulling, or at right angles to the fiber direction. Structure size and 2 x 6 shaku or 3 x
Taking into account the standard size of plywood, such as 6 shaku, the layout must be carefully examined in advance, and the allowable stress level must be divided into two types, the fiber direction and the perpendicular direction, and the design calculation must be performed. Cheap. Moreover, it is the carpenters and other workers who are not involved in such design calculations that handle plywood at the construction site, and the intention of the designer is often not sufficiently communicated. It is dangerous because it can break and cause serious disasters. As described above, in order to use it as a structural material such as a formwork or a roofing material that receives a large force, it is strongly required that the plywood has no anisotropy in performance.

[0009]

[Means for Solving the Problems] In order to solve the above problems, the present inventors have conducted diligent research aiming at strengthening a plywood in which a plurality of wood veneers are bonded with an adhesive. As a result of continuing, it was found that a reinforced plywood having excellent properties can be obtained by applying a coating treatment to the plywood with a reinforcement-imparting resin composition effective for imparting reinforcement to the plywood by a specific method, and completed the present invention. did. In the present invention, for example, in plywood, the one having a tensile strength and elastic modulus sufficiently larger than the base material is used as a reinforcing material between wood veneers, and a fiber reinforcing material for reinforcing continuous fibers such as glass fiber and carbon fiber is used. As the base material of the wood veneer, the fiber reinforcing material for imparting the reinforcement is interposed and heat pressed, and a phenol resin or the like is used as an adhesive to be applied to the wood veneer, and silane is used as the reinforcing material. It is impregnated with a coupling agent to improve the adhesion performance between the base material adhesive and the reinforcing material by a chemical covalent bond.As a result, even though it is plywood, it has excellent performance as a wood material without anisotropy. In addition to having the above, by reinforcing with glass fiber, a material having strength superior to that of natural material can be obtained.

The reinforcing material used to increase the strength and elastic modulus of the base material is required to have sufficiently higher tensile strength and elastic modulus than the base material. Further, in order for the reinforcement material to take charge of the force used for the base material, it is necessary that the base material and the reinforcement material are firmly attached to each other, and that the force is transmitted from the base material to the reinforcement material. is there.

The present invention relates to a plywood made of a fibrous wood veneer used as a structural material for construction, which has superhigh strength, superhigh elastic modulus and toughness. The present invention relates to a floor-like material, a roofing material, a wall material or the like, or a plate-like composite material used for construction work, and a method for reinforcing a plywood obtained by bonding a plurality of wood veneers with an adhesive and a reinforced plywood. Regarding The object of the present invention is, when laminating a plurality of veneers, which are thin wooden plates, via an adhesive, sandwich a reinforcing fiber imparting material between the veneers, and strengthening resin composition to the veneer and the reinforcing fiber imparting composition. Impregnate the material and react
The present invention provides a reinforced plywood obtained by curing and a method for producing the reinforced plywood.

That is, according to the present invention, in a plywood in which a plurality of wood veneers are bonded together with an adhesive, a fiber reinforcing material for strengthening is sandwiched between the respective veneers to be bonded, and the veneers are bonded together with the adhesive. And a reinforcing imparting fiber between at least the first layer and the second layer veneer from at least the surface layer of the plywood obtained by laminating a plurality of fibrous wood veneers with an adhesive. It is a reinforced plywood characterized by being laminated by laminating a plurality of materials via an adhesive with a reinforcing material interposed. In the above, a phenol resin layer is preferable as the adhesive, and continuous fibers such as glass fiber and carbon fiber are used as the reinforcing material. Further, it is preferable that the wood veneer is coated with the reinforcement-imparting resin composition, and the reinforcing fiber is impregnated with an adhesion reinforcing agent, for example, a silane coupling agent. Alternatively, it is also preferable that an adhesive reinforcing agent such as a silane coupling agent is added to the adhesive of the base material to form a plywood in which the adhesion performance between the adhesive and the reinforcing material is improved by a chemical covalent bond.

Further, the adhesive resin layer of the wood veneer is an adhesive synthetic resin selected from phenol resin, urethane resin, melamine resin and urea resin, and the strengthening resin composition applied to the wood veneer is It is preferable that the wood veneer is chemically belonging to the same group as the phenolic resin or the like used as an adhesive for the wood veneer. Further, it is preferable that the reinforcement-imparting resin composition is an adhesive synthetic resin composition selected from a phenol resin, a urethane resin, a melamine resin and a urea resin.

Further, one wood veneer has a thickness of about 1 to 4 mm, and plywood is made from 3 to 21 wood veneers with an adhesive.
It is also preferable that they are stuck together.

Furthermore, the present invention is a method for manufacturing a plywood in which a plurality of wood veneers as described above are bonded to each other with an adhesive, at least between the surface layer and the first layer veneer and the second layer veneer. A method for producing a reinforced plywood, which comprises laminating and laminating a plurality of reinforcing fiber-reinforced materials via an adhesive. During the production, it is impregnated with a resin-reinforcing resin composition of wood veneer, then reacted, a method for producing a reinforced plywood that is subjected to a curing treatment, and further a fiber-reinforcing material for reinforcement with an adhesion reinforcing agent such as a silane coupling agent. Preferred is a method for producing a reinforced plywood which is impregnated or treated by adding an adhesion-strengthening agent to the reinforcement-imparting resin composition, and then reacted and cured.

In the present invention, at least 1 from the surface of the plywood.
A reinforcing material is inserted into the adhesive layer between the first veneer plate of the second layer and the second veneer plate, and the shape and adhesive of the reinforcing material are further devised to provide a plywood having no anisotropy in performance. By appropriately selecting the type of the reinforcing material, the performance of the conventional plywood can be greatly improved, and the plywood without anisotropy can be provided.

As the reinforcing material, one having tensile strength and elastic modulus sufficiently larger than that of plywood can be preferably used. Examples of such a material include those known as inorganic fibers, and examples thereof include continuous fibers such as glass fibers and carbon fibers (hereinafter referred to as reinforcing materials such as glass fibers).

In addition, alpha alumina and gamma alumina type alumina fibers, boron composite fibers, silicon carbide-carbon composite fibers, silicon carbide fibers-tungsten composite fibers, silicon carbide fibers, silicon carbide fibers-epoxy resin composite fibers, silicon carbide. Fiber-aluminum composite fiber, silicon carbide fiber-glass composite fiber, Si-Ti-C-O based fiber (tyranno fiber), tyranno fiber-aluminum composite fiber, tyranno fiber-epoxy resin composite fiber and the like can also be mentioned. It can be appropriately used without departing from the object of the invention.

Examples of carbon fibers include high-performance carbon fibers, general-purpose carbon fibers, activated carbon fibers, flame resistant carbon fibers, vapor-grown carbon fibers, and the like. Those produced from polyacrylonitrile (PAN) fibers, coal, etc. Examples include liquid crystal pitch-based products manufactured from ethylene tar or slurry oil obtained from coal tar or petroleum, naphthalene, and the like, those manufactured from regenerated cellulose, those manufactured from phenolic fibers, and the like. General-purpose carbon fiber is preferable in terms of price.

As the glass fiber, fiber alone, glass chopped strand map, glass roving, glass yarn, glass cloth, glass tape, treated glass cloth, glass roving cloth, or those obtained as a raw material Or those having properties equal to or higher than these. Reached fibers can also be used.
Glass fiber is preferably used as a reinforcing material.

The shape of the reinforcing material is preferably a mesh. The main direction is the direction perpendicular to the fiber direction of the first layer veneer, and a reinforcing material such as glass fiber is arranged to reinforce the direction. In the fiber direction of the first-layer veneer, reinforcing materials such as glass fibers in the main direction are connected to each other, and in order to disperse the force, an amount equivalent to that of the reinforced concrete is arranged. Further, when it is desired to eliminate the anisotropy of the plywood and significantly improve the strength and hardness, the amount of the reinforcing material such as glass fiber arranged in the above two directions may be increased.

Adhesives for plywood include phenol resin, melamine resin, urethane resin, urea resin, polyester resin, epoxy resin, silicone resin or co-condensation of these resins, which has a strong physical adhesion to wood veneer. Resin, for example, urea-melamine co-condensation resin (hereinafter,
(Phenolic resin, etc.) is used. Physical adhesion is relatively good with a reinforcing material such as glass fiber, but it is more preferable to add the following improvements so as to obtain a more optimal adhesive effect.

The phenol resin is obtained by condensing phenols such as phenol, cresol, xylenol, bisphenol A, bisphenol F, styrenated phenol, resorcinol, paracumylphenol and aldehydes such as formaldehyde or its derivatives. There are things. Examples of the melamine resin include those obtained by condensing melamine or its derivative with aldehydes such as formaldehyde or its derivative. Examples of the urea resin include those obtained by condensing urea or its derivative with aldehydes such as formaldehyde or its derivative.

In order to secure the adhesion between the reinforcing material such as glass fiber and the phenolic resin which is the adhesive for the plywood, the surface of the reinforcing material such as the glass fiber is preliminarily separated from the same kind of phenolic resin as the adhesive for the plywood. The selected reinforcing resin composition is impregnated. Hereinafter, this treatment is referred to as resin impregnation processing. By doing this, the amount of phenolic resin, etc. used for laminating the wood veneers is improved, the adhesion with the reinforcing material such as glass fiber is sufficiently achieved, and the force from the veneers is sufficiently transmitted and reinforced. Increase the effect. The amount of phenolic resin, etc. used to impregnate the reinforcing material such as glass fiber with resin is about 5 to 50.
%, Preferably about 20-30%.

Further, in order to strengthen the adhesion of the reinforcing material such as glass fiber and the adhesive of the plywood such as phenol resin to the physical one more than the physical one, a special adhesion reinforcing agent such as a silane compound (hereinafter, silane coupling) is used. Agent)) is used. The silane coupling agent can be added to the phenol resin or the like to be resin-impregnated, the sizing agent used to form the reinforcing material such as glass fiber, or both of them. The silane coupling agent can be used by selecting a chemically optimal one for the phenol resin or the like which is the adhesive for the plywood. For example, for the phenol resin, a silane coupling agent having an amino group or an epoxy group can be used. It can be selected and used.

As such a silane coupling agent, a compound represented by the general formula X ... Si (OR) ₃ (where X is a functional group (eg vinyl group, amino group, etc.) that reacts with an organic substance. , An alkylamino group, a methacryloxypropyl group, an alkylmercapto group, a mercapto group, an epoxy group), and R is a hydrolyzable functional group (for example, a methoxy group, an ethoxy group, an acetoxy group, a halogen atom). The things that are done are listed.

FIG. 8 is a view for explaining the bonding action between the adhesive 3 and the glass fiber 2'by this silane coupling agent. The OR portion of the silane coupling agent 10 is hydrolyzed and converted into OH, which causes a chemical covalent bond between an organic substance and an inorganic substance. Since this chemical covalent bond is an intermolecular bond due to a chemical reaction, it exhibits a stronger bonding force than in the case where it is physically attached. The silane coupling agent 10 is selected and used so that the group X chemically reacts with the adhesive (or the reinforcing resin composition) 3 used.

As the silane coupling agent, for example,
Vinylalkoxysilanes such as vinyltrichlorosilane, allyltrichlorosilane, allyldichlorosilaneresorcinol, dimethoxypropyl-trimethoxysilane, vinyl-tris- (β-methoxyethoxy) silane and vinyl-triethoxysilane, γ-methacryloxypropyl- Trimethoxysilane, β- (3,4-epoxycyclohexyl) ethyl-trimethoxysilane, γ-glycidoxypropyl-trimethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, γ- (β-formyl Ethyl) mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ- [bis (β-hydroxyethyl)] aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyiene Trimethoxysilane, .gamma.
(Β-aminoethyl) aminopropyldimethoxymethylsilane, N- (trimethoxysilylpropyl) ethylenediamine, N- (dimethoxymethylsilylisobutyl)
Vinylalkoxysilanes such as ethylenediamine may be mentioned.

The silane coupling agent is further represented by the general formula R ¹ _4-n Si (OOR ² ) _n (wherein R ¹ and R ² are organic groups, and n is 1 to 4). There are things. Examples of R ¹ and R ² include a methyl group, a t-butyl group, a vinyl group, an allyl group, a cumyl group, and a p-menthyl group.

As the adhesion reinforcing agent, in addition to the above silane coupling agent, for example, chromium / methacrylate complex compound, phosphoric acid monoalkyl ester, diphenylphenylphosphonate, dimethylmethylphosphonate, diethylethylphosphonate, bis- (2-ethylhexyl). −
Phosphonates such as 2-ethylhexylphosphonate and dibutylbutylphosphonate, dimethyl phosphite, diethyl phosphite, diisopropyl phosphite, dioctyl phosphite, trifunctional phosphite and other phosphite Is mentioned.

In improving the adhesion, the addition of a silane coupling agent causes a chemical covalent bond between the organic phenol resin and the inorganic glass fiber or other reinforcing material, so that the resin alone is used. Stronger adhesion was obtained than the physical one when doing.

As a result, as shown in FIGS. 9 (a) and 9 (b) for explaining the plywood breaking test, the plywood 1 thus obtained was subjected to a bending test until it was destroyed. In the glass fiber 2'of No. 1, while some of the inner parts are pulled out, the glass fibers 2'are cut unevenly and unevenly as shown in the right figure, while as shown in the breaking test explanatory view of the plywood of FIG. The reinforcing material 2 such as glass fiber impregnated with the coupling agent is cut evenly at the break position of the plywood 1 as shown in the right figure, showing a state where the adhesion with the resin is surely secured. Shows a situation similar to that when it is pulled in the atmosphere and ruptures, and the high strength and the high functionality of the elastic modulus of the reinforcing material are sufficiently exhibited. It should be noted that (a) is a state when the glass fiber is pulled in air and is broken, and (b) is a reinforcing plywood 1
The figure shows the state when a vertical load is applied to the fracture. Figure 1
In No. 0, a plurality of single plates having the same fiber direction may be laminated in the same direction, and an adhesive layer containing a reinforcing material may be provided between them. Or, a plurality of veneers are laminated with different fiber directions, that is, a plurality of veneers with the same fiber direction are in mutually different directions, for example, the fiber directions of the trees are orthogonal to each other, and between them. An adhesive layer containing a reinforcing material may be provided.

Further, according to the present invention, the plywood is, for example, about 1
~ 4 mm thick, preferably 1-3 mm thick fibrous wood veneer, preferably 3 fibrous wood veneer with an adhesive ~
21 pieces, preferably 5 to 15 pieces are stuck together. Such a fibrous wood veneer has a gap therein, and the gap portion can be impregnated with the reinforcement-imparting resin composition. Generally speaking, in a case where a plurality of wood veneers are adhered to each other with an adhesive layer so as to form a multilayer, the reinforcement-imparting resin composition is blocked by the adhesive part and is not impregnated. .

Further in accordance with the present invention, the reinforcement-imparting resin composition is, for example, a phenolic resin, as described above.
Adhesive synthetic resin composition selected from urethane resin, melamine resin, and urea resin can be preferably used, but it is not limited to this as long as it has plywood strengthening ability according to the object of the present invention. it can.

In the present invention, the reinforcement-imparting resin composition is preferably impregnated into the veneer constituting the plywood. It is also preferable to impregnate an adhesive portion of the plywood, which is interposed between the first-layer veneer and the second layer, with an impregnated portion, and to interpose a fiber-reinforcing material for strengthening the portion. In this way, it is preferable to treat the space between the first layer wood veneer and the second layer wood veneer on the front side and the back side of the plywood, respectively. In addition, in the present invention, in order to provide the required strength, the reinforcement-imparting resin composition is impregnated from the surface layer of the plywood to a plurality of layer portions close to the surface layer portion, and a reinforcing fiber-reinforcing material is interposed in each adhesive portion. You can also let it. As the reinforcing fiber-reinforcing material used in the present invention, those which give a tensile strength and an elastic modulus sufficiently higher than those of the base material are preferable.

Examples of the plywood used in the present invention include those obtained by laminating thinly peeled wooden boards and adhering them. Examples of raw logs used in these include raw trees of tropical forests such as lauan and conifers such as cedar, but not limited to these, and those commonly used can also be used.

Such plywood will be described in more detail below. Figure 1 shows 5 layers of normal plywood 1 ', thickness 12mm
The vertical cross-sectional view of the configuration of the example of FIG. The thickness is, for example, about 2 mm / sheet. The second and fourth layers use raw wood cores, which are usually relatively weak in relatively old parts. The thickness is, for example, about 3 mm /
It is a sheet. Figure 2 illustrates the fiber orientation of a veneer and its performance. Strong in the fiber direction, but weak in the direction perpendicular to the fiber direction. Therefore, in order to increase the strength of the plywood, the first, the third and the fifth layers (the veneer of A) and the second and the fourth layers are used.
The layers (single plate of B) are joined by making their fiber directions orthogonal to each other.

FIG. 3 illustrates strength against bending stress in a plywood plate made of an even number of veneers. When the young log of the first layer is on the top and the fourth log (even number) of the old log is on the bottom, it is weak against the force from above. On the other hand, when it is placed in the opposite way, it is strong against the force from above. This is a sapwood of raw wood, and can exert its strength because the veneers of the first and third layers, which are made from young parts, are in tension.

FIG. 4 illustrates the anisotropy of the performance of the plywood 1 '. It is strong against tension and bending in the fiber direction of the veneers of the first, third and fifth layers, but weak in the direction perpendicular thereto. FIG. 5 shows a reinforcing fiber imparting material 2 according to an embodiment of the present invention, in which a mesh reinforcing fiber reinforcing material 2 is used. In the fiber direction of the veneer of the first layer, the amount of the fiber reinforcing material 2 for imparting reinforcement is the amount shown by the fiber II, but in the direction perpendicular to the fiber direction of the veneer of the first layer, it is shown by the fiber I. Used in sufficient quantity to give strength.

FIG. 6 illustrates the arrangement of the reinforcing fiber reinforcement 2 according to the invention as a more preferred one plywood 1 arrangement. If the reinforcement-providing fiber reinforcing material 2 is interposed in the adhesive layer 3 between the first layer wood veneer and the second layer wood veneer on the front side and the back side of the plywood 1, the same performance can be obtained regardless of the front and back sides. Can be demonstrated. FIG. 7 is a schematic illustration of the effects obtained by the plywood according to the present invention, and the inside of the broken line shows the effects obtained by the plate according to the present invention. Fiber II
When a small amount of is used, the anisotropy of the plywood is improved as shown by the effect A in the left figure. When a large amount of the fiber II is used (however, the amount of the fiber I> the fiber II is used), not only the anisotropy of the plywood as shown in the effect A is improved but also the effect B in the right figure shows. As a result, the overall strength is greatly improved.

In order to manufacture such a reinforced plywood, first, the reinforcing material 2 is interposed between the veneers coated with the adhesive so as to obtain a laminated body. Next, for example, 185 degrees Celsius, 3
A reinforced plywood 1 of a product is obtained by pressure molding at 0 kgf / cm ² for 5 minutes by hot pressing at high temperature and high pressure. In addition,
The overall structure of such a manufacturing apparatus is known.

Further, in this plywood structure, a special addition is made in order to strengthen the adhesion of the phenol resin or the like of the reinforcing material 2 such as glass fiber and the adhesive 3 for bonding the single plate of the base material to the physical one or more. It is preferable to use an agent, and it is preferable to select a silane compound as the additive. Hereinafter, this is referred to as a silane coupling agent 10. The silane coupling agent 10 is either in the phenol resin 3 or the like of the adhesive to be impregnated with the resin, in the sizing agent used for forming the fiber reinforcing material 2 for imparting reinforcement such as glass fiber, or in both of them. Added to. As the silane coupling agent 10, an optimal one is selected for the phenol resin or the like of the base material adhesive 3. For example, a silane coupling agent having an amino group or an epoxy group is used for the phenol resin.

In improving the above-mentioned adhesive force, by adding a silane coupling agent, the organic phenolic resin 3 and the reinforcing material 2 such as the inorganic glass fiber come to form a chemical covalent bond. It gave stronger adhesion than the physical one when used in.

FIG. 8 is a view for explaining the bonding action of the adhesive 3 and the glass fiber 2 of the reinforcing material by the silane coupling agent 10. The OR portion of the silane coupling agent 10 is hydrolyzed and converted into OH, which causes a chemical covalent bond between an organic substance and an inorganic substance. Since this chemical covalent bond is an intermolecular bond due to a chemical reaction, it exhibits a stronger bonding force than in the case where it is physically attached. There, the base material adhesive 3 uses a wood veneer as a raw material and a phenol resin having a strong physical adhesive force. Phenolic resin, etc. is an adhesive synthetic resin selected from phenolic resin, urethane resin, melamine resin, and urea resin, and these phenolic resins, etc. are also compared with the reinforcing material 2 of continuous fiber such as glass fiber and carbon fiber. It has good physical and physical adhesion, but it is not as good as wood veneer, and it cannot be said to be the optimum adhesive 3 as it is.

Reinforcing material 2 such as glass fiber and adhesive 3 for base material
In order to ensure the adhesion with the phenol resin or the like, the surface of the reinforcing material 2 such as glass fiber is previously impregnated with the same kind of phenol resin or the like as the base material adhesive 3 separately. This is to supplement that the amount of the phenolic resin or the like required to manufacture the plywood 1 of the base material by bonding the individual veneers does not sufficiently adhere to the reinforcing material 2 such as glass fiber. The amount of the phenol resin or the like to be impregnated into the reinforcing material 2 such as glass fiber is 5 to 50%, preferably 20 to 30%.

As a result, the plywood 1 thus obtained is obtained.
When a bending test was conducted until the glass fiber was destroyed, it was found that the glass fiber 2'without being impregnated with the silane coupling agent was fluffy and cut unevenly in a state where a part of the inside was pulled out (Fig. 9). On the other hand, in the reinforcing material 2 such as glass fiber impregnated with the silane coupling agent 10, as shown in FIG. 10, the plywood 1 is cut evenly at the break position to ensure the adhesion with the resin. This rupture property shows the same situation as when it is ruptured by being pulled in the atmosphere, and the high strength and high elasticity of the reinforcing material are fully exhibited. . The plywood used in the present invention is not limited to the above.

[0047]

EXAMPLES The present invention will be described in more detail below with reference to examples. In the following examples, all "parts" mean "parts by weight". 1st, 3rd and 5th layer wood veneer (average thickness about 2 mm, 1800 mm (fiber direction length) x 6
00 mm) and second and fourth layers of wood veneer (average thickness of about 3 mm, 1800 mm x 600 mm (fiber direction length)) are arranged, and cut between them to an appropriate size. The glass fibers (average length of about 30 mm) are densely arranged so as to be orthogonal to the fiber direction of the wood veneer as shown in FIG. 5, and the reinforcing material 2 is sparsely arranged in the fiber direction of the wood veneer. Intervene. Further, a phenol resin is applied as an adhesive 3 between the individual plates. The reinforcing material 2 made of the glass fiber is previously impregnated with a silane coupling agent.

The constituent materials thus obtained were arranged so as to form a laminate having a total thickness of about 12 mm, and then 185
A hot press treatment was carried out at a temperature of 30 ° C. and a pressure of 30 kgf / cm ² for 5 minutes. The physical properties of the reinforced plywood 1 were measured after curing the obtained plywood having a length of 1,800 mm, a width of 600 mm and a thickness of 12 mm in a thermostatic chamber at 25 ° C. for 24 hours. In the case of ordinary plywood without the above treatment, the bending Young's modulus E (× 10 ⁴ k) when bent at a right angle as shown in FIG.
gf / cm ² ) is E = about 3.0 to 3.5, bending strength σ (kgf / cm ² ) is about σ = 300 to 350,
When bent in the fiber direction of the plywood surface layer, E = about 5.0,
σ is about 500. On the other hand, in the case where the fiber reinforcing material 2 made of glass fibers and having a tensile load per width of 5 cm is fiber I = 300 kg and fiber II = 10 kg, E = 5.0 of the reinforced plywood 1, When σ = about 500, and when the tensile load of the glass fiber per width of 5 cm was fiber I = 450 kg and fiber II = 250 kg, the performance was improved to about E = 6.0 and σ = 700.

Further, when a bending test was conducted until the plywood thus obtained was destroyed, a glass fiber without impregnation with a silane coupling agent was fluffed with a part of the inside pulled out. 10 is cut irregularly (FIG. 9), whereas the case of using a reinforcing material such as glass fiber impregnated with the silane coupling agent 10 is shown in FIG.
As shown in Fig. 5, the plywood 1 is cut at the breaking position, and the resin is surely adhered. This breaking property is similar to that when the plywood 1 is broken by being pulled in the atmosphere. The results show that the high strength and the high functionality of the elastic modulus of the reinforcing material are sufficiently exhibited.

[0050]

According to the present invention, as an adhesive for plywood,
By using a phenol resin such as a phenol resin, a melamine resin, a urethane resin, or a urea resin, and interposing a reinforcing material such as glass fiber, the bending strength and elastic modulus of the plywood can be significantly improved. Also, in order to make the adhesion of the reinforcing material with the adhesive stronger and more reliable, the surface of the reinforcing material such as glass fiber is modified to strongly integrate it with plywood, thereby eliminating the anisotropy. The bending strength and elastic modulus of plywood can be significantly improved.
In particular, by adding a silane coupling agent, an adhesive such as an organic phenolic resin and a reinforcing material such as an inorganic glass fiber are chemically and strongly covalently bonded (intermolecular bond),
A stronger adhesive force than the physical bond strength can be obtained.

When the reinforced plywood thus obtained is subjected to a bending test until it breaks, the reinforcing material such as glass fiber shows a breaking property similar to that when it is pulled in the atmosphere, and Due to the high functionality provided by, it is possible to sufficiently provide a high elastic modulus and high strength. Since the reinforced plywood of the present invention has high strength, high elastic modulus, and toughness, it is particularly suitable as a flooring material, a roofing material, a wall material, or a construction material for construction work. It can be used. Further, although it is a plywood which is a set of wood veneers, it has excellent performance as an artificial wood material by being reinforced with glass fibers. According to the manufacturing method of the present invention, the above-mentioned reinforced plywood can be provided easily and at low cost.

[Brief description of drawings]

FIG. 1 is a diagram showing a vertical cross-sectional view of a configuration of an example of a normal plywood having 5 layers and a thickness of 12 mm.

FIG. 2 is a diagram explaining the fiber direction of a veneer and its performance.

FIG. 3 is a diagram illustrating strength against bending in a plywood plate made of an even number of single plates.

FIG. 4 is a diagram illustrating anisotropy of performance of plywood.

FIG. 5 is a view for explaining the arrangement of fiber reinforcing material for imparting reinforcement according to the present invention.

FIG. 6 is an explanatory view showing a state in which the fiber reinforcing material for imparting reinforcement according to the present invention is arranged in the entire plywood.

FIG. 7 is a diagram schematically explaining the effect obtained by plywood according to the present invention.

FIG. 8 is a view for explaining the bonding action of a silane coupling agent and an adhesive with glass fiber.

FIG. 9 is a diagram illustrating adhesion between glass fiber and resin when a silane coupling agent is not included.

FIG. 10 is a diagram for explaining the adhesion to a resin when a silane coupling agent is included, wherein FIG. 10A shows the cutting property of glass fiber alone in the atmosphere, and FIG. 10B shows the adhesion with resin. The cutting property in the case is shown.

[Explanation of symbols]

 1: Reinforced plywood 1 ': Plywood 2: Reinforcing material 3: Adhesive layer 10: Silane coupling agent

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location B32B 21/10 C09J 183/04 (72) Inventor Yoshihiro Takekawa 1-2-3 Shibaura, Minato-ku, Tokyo No. Shimizu Construction Co., Ltd. (72) Inventor Chiaki Suzuki One of the first places in Tajuku, Shimokawa, Izumi-cho, Iwaki, Fukushima Prefecture Onahama Plywood Co., Ltd. In Inahama Plywood Co., Ltd. (72) Inventor Kazuki Noguchi 3-3-9, Nihonbashi, Chuo-ku, Tokyo Inside Yoshi Main Forestry Co., Ltd. (72) Inventor Kazuo Iijima 1st East, Gono, Fukushima-shi, Fukushima Nitto Boseki Within the corporation

Claims (12)

[Claims] 1. A plywood laminated with a plurality of wood veneers via an adhesive, wherein a fiber reinforcing material for strengthening is sandwiched between the veneers to be adhered, and the veneers are bonded via an adhesive. Reinforced plywood. 2. A plurality of laminates are made by laminating a reinforcing material of reinforcing fibers between at least the surface layer of the plywood and the first-layer wood veneer and the second-layer wood veneer with an adhesive. The reinforced plywood according to claim 1, wherein 3. The reinforcing material is glass fiber, carbon fiber,
Alumina fiber, boron composite fiber, silicon carbide-carbon composite fiber, silicon carbide fiber-tungsten composite fiber, silicon carbide fiber, silicon carbide fiber-epoxy resin composite fiber, silicon carbide fiber-aluminum composite fiber, silicon carbide fiber-glass composite fiber , Si-Ti-CO fiber,
The reinforced plywood according to claim 1 or 2, wherein the reinforced plywood is a fiber-reinforcing material selected from the group consisting of Tyranno fiber-aluminum composite fiber and Tyranno fiber-epoxy resin composite fiber. 4. The reinforced plywood according to any one of claims 1 to 3, wherein the reinforcing material is a reinforcing fiber-reinforced material made of glass fiber or carbon fiber. 5. The reinforced plywood according to claim 1, wherein the fiber reinforcing material is impregnated with an adhesive reinforcing agent, and the individual veneers are bonded together via the adhesive. 6. The adhesion reinforcing agent is a silane coupling agent, and the silane coupling agent has the general formula X ... Si (OR) ₃ (where X is a functional group that reacts with an organic substance). Group, vinyl group,
A group selected from the group consisting of an amino group, an alkylamino group, a methacryloxypropyl group, an alkylmercapto group, a mercapto group, and an epoxy group, R is a hydrolyzable functional group, and a methoxy group, an ethoxy group, an acetoxy group. And a group selected from the group consisting of halogen atoms. ) The reinforced plywood according to claim 5, which is represented by 7. A wood veneer is impregnated with a resin composition for strengthening, and is laminated with an adhesive, and the resin composition for reinforcing is a phenol resin composition, a melamine resin composition, a urethane resin. The reinforced plywood according to any one of claims 1 to 6, which is a synthetic resin composition selected from the group consisting of a composition, a urea resin composition, and a co-condensable resin composition of these resins. 8. The adhesive is a synthetic resin selected from the group consisting of a phenol resin, a melamine resin, a urethane resin, a urea resin and a co-condensable resin of these resins. Reinforced plywood according to any one of. 9. The reinforced plywood according to any one of claims 1 to 8, wherein a silane coupling agent is added to the adhesive and they are bonded together via the adhesive. 10. A plywood obtained by laminating a plurality of wood veneers with an adhesive, and laminating them with a reinforcing fiber imparting material interposed therebetween, wherein the adhesive is a phenol resin, a melamine resin, a urethane resin, and a urea resin. Alternatively, it is a synthetic resin selected from the group consisting of co-condensable resins of these resins, the reinforcing material is a fiber reinforcing material with a reinforcement made of glass fiber or carbon fiber, and the synthetic resin is bonded to the wood veneer. Agent is impregnated and the fiber of the reinforcing material is impregnated with the silane coupling agent, or the silane coupling agent is added to the adhesive of the wood veneer to chemically bond the adhesive performance of the base material and the reinforcing material. A reinforced plywood according to claim 1, which is a plywood improved by 11. The adhesive synthetic resin layer of a wood veneer is an adhesive synthetic resin selected from the group consisting of phenol resins, urethane resins, melamine resins and urea resins or co-condensable resins of these resins, The adhesive to be impregnated into the veneer belongs to a group chemically similar to the adhesive synthetic resin used as the adhesive for the wood veneer, and is a fiber reinforcement made of glass fiber or carbon fiber. Is the one that is impregnated with a silane coupling agent, or that is mixed with a silane coupling agent chemically belonging to the same group as the adhesive synthetic resin composition used as an adhesive in the wood veneer. The reinforced plywood according to claim 10, which is impregnated. 12. A wood veneer has a thickness of about 1 to 4 mm, and plywood is made by laminating 3 to 21 wood veneers with an adhesive, and the wood veneer. 12. An odd number of sheets are bonded together,
Reinforced plywood according to any one of.