JPH07227806A - Wooden composite base material - Google Patents

Abstract

PURPOSE:To inhibit mainly the occurrence of a warp by arranging a long wooden fiber board with an individually specified air-dry specific gravity on both front and rear layer parts and at the same time, laminating three different types of wooden veneer with an individually specified air-dry specific gravity on the inner side of the wooden fiber board in such a manner that these veneers are positioned in parallel with or at right angles with the long side of the wooden fiber board. CONSTITUTION:A wooden composite base material A consists of both front and rear layer parts formed using long wooden fiber boards 1 with individually specified air-dry specific gravities of 0.65 to 0.9. On each inner side of both wooden fiber boards 1, 1, both first wooden veneers 2, 2 with individually specified air-dry specific gravities of 0.65 to 0.9 are laminated so that both first wooden veneers 2, 2 are positioned with their fiber directions set in parallel with the long side of the wooden fiber boards 1, 1. In addition, on the inner side of both first wooden veneers 2, 2, both second wooden veneers 3, 3 with individually specified air-dry specific gravities of no more than 0.65 are laminated in such a manner that their respective fiber directions run almost at right angles with the long side of the wooden fiber boards 1, 1. Further, on the inner side of both second wooden veneers 3, 3, third wooden veneers 4 with an air-dry specific gravity of no more than 0.65 is laminated with their respective fiber directions set in parallel with the long side of the wooden fiber boards 1, 1.

Description

Detailed Description of the Invention

[0001]

[0001]

[0002]

FIELD OF THE INVENTION The present invention relates to a composite wood fiber board called MDF or a wood fiber board having a slightly higher specific gravity and a wood veneer, and is used as a base material for building boards such as floor boards and wood makeup for furniture. The present invention relates to a wood composite base material used for a plate base material.

[0003]

[0002]

[0004]

2. Description of the Related Art Conventionally, plywood, particle board, and medium-quality fiberboard called MDF have been used as a wood base material. However, plywood made of lauan wood etc. is relatively lightweight and has toughness and nail holding power. Although easy, particle boards and medium-quality fiberboards have the drawbacks of high specific gravity (air-dry specific gravity of 0.7 to 0.8) and poor toughness and nail holding power. Recently, it has become difficult to obtain a good plywood due to the situation of wood resources, and therefore, a technique for compositely integrating a wood veneer and a medium-quality fiberboard has been disclosed. For example, JP-A-3-4220
No. 2 has a total thickness of 9 mm or more, and a middle fiberboard is integrated on the front and back with the plywood as the center, and the thickness ratio of the plywood is 5
There are some with 5% or more.

[0005]

[0003]

[0006]

However, in this prior art, a plywood consisting of only wood veneer and a density of 0.75 g / c is used.
m ³ of medium quality fiberboard is simply laminated and has a density of 0.5
The lauan veneer and the medium-quality fiberboard having g / cm ³ have a drawback that they tend to warp due to the difference in the absorption of the adhesive and the humidity during use. By the way, if a wood veneer with a high specific gravity is used, the air-dry specific gravity of the wood veneer is close to that of a medium-quality fiberboard. In addition, there is a defect that it is hard when cutting or driving a nail, and it is liable to cause bending, abrasion of a cutting tool, bending of a nail and the like.

[0007]

The present invention has been made in view of the above problems, and provides a wood-based composite substrate which has improved warpability and processability by preventing warpage during stacking and integration and during use. .

[0008]

[0005]

[0009]

Therefore, in the wood composite base material of the present invention, in claim 1, the front and back layers are made of wood fiberboard having a long air-dry specific gravity of 0.65 to 0.9, A wood veneer having an air-dry specific gravity of 0.65 to 0.9 is laminated inside each of the wood fiberboards so that the fiber direction thereof is substantially parallel to the long side of the wood fiberboard, and the air-dry specific gravity of 0. A wood veneer of less than 65 is laminated with its fiber direction substantially orthogonal to the long side, and a wood veneer having an air-dry specific gravity of 0.65 to 0.9 is further inside thereof with its fiber direction substantially parallel to the long side. In the second aspect, the air-dry specific gravity of 0.65 to 0.
Using tropical hard wood veneer instead of 9 wood veneer,
It is characterized by using a coniferous wood veneer instead of a wood veneer of less than 0.65.

[0010]

[0006]

[0011]

With the above construction, in the wood composite base material of the present invention, in the first aspect, the wood fiber board of the front and back layers and the wood veneer arranged inside the wood fiber board which influences the strength and warp in the long side direction. 65-
Within the specific gravity range of 0.9, the existence of voids inside both materials is approximated to reduce the difference in the absorption of the adhesive during lamination and the difference in the migration of moisture during use. On the other hand, a wood veneer having an air-dry specific gravity of less than 0.65, which is arranged inside a wood veneer of 0.65 to 0.9, contributes to overall weight reduction and cutting workability and nailability, while Since the fiber direction is substantially orthogonal to the long side, the influence on the strength and warpage is small. Further, the above-mentioned 0.
Since a wood veneer similar to the wood veneer of 65 to 0.9 is located in the same direction, it contributes to the strength and balance of bending and the wood mouth as a neutral axis.

[0012]

Therefore, the wood composite base material of the present invention is less likely to warp during manufacture or use, has less weight increase than conventional plywood, and is less likely to cause bending, abrasion of blades, bending of nails, etc. It will be good.

[0013]

According to a second aspect of the present invention, the air-dry specific gravity of the wood veneer of the first aspect is specified instead of the classification of the wood veneer, and the operational effect is the same as that of the first aspect.

[0014]

[0009]

[0015]

EXAMPLES Next, examples will be described with reference to FIG. 1 of the present invention.
FIG. 1 is a side view of a wood composite material base material A. Long wood fiberboards 1 and 1 on the front and back surfaces are JIS A590 called MDF.
Medium fiberboard specified in 6 or JIS A5906
A slightly higher specific gravity than wood fiberboard with an air dry specific gravity of 0.65
0 to 9, wood fibers made of thermosetting resin binder such as urea, melamine, and urea melamine to a thickness of 1 to
It is formed into a flat plate of 4 mm. Air dry specific gravity of 0.
Was the was the 65-0.9, the bending strength becomes about 250 kgf / cm ² or less is less than 0.65, conventionally obtained as an alternative to fewer or using 500 kgf / cm ² or more wood veneer plywood wood Does not satisfy the strength performance of the base material,
This is because if it exceeds 0.9, there are few voids and it becomes hard and brittle, and the processing characteristics required for wood materials such as cutting and nailing properties are poor.

[0016]

Reference numerals 2 and 2 are wood veneers having an air-dry specific gravity of 0.65 to 0.9 and arranged inside the respective wood fiber boards 1 and 1 so that their fiber directions are substantially parallel to the long sides. Thickness is 1 to 4 mm
So, the tree species names are Kapoor, Quruin, Nyato,
Tropical hardwoods such as Apiton, Scepter, Kempus, Ramin and Merantic which fall within the above specific gravity range. It also includes wood veneers such as beech, hippo and other hardwood from Japan that fall within the above specific gravity range. Air dry specific gravity of 0.65
The reason why 0.9 is set is that the various properties due to the voids are brought close to each other according to the air-dry specific gravity of the wood fiber board 1, and the strength decrease due to the wood fiber board 1 which is inferior in strength to the wood veneer due to the large bending strength. This is to make up for it.

[0017]

Reference numerals 3 and 3 are wood single sheets having an air-dry specific gravity of less than 0.65 laminated inside the wood veneers 2 and 2 having an air-dry specific gravity of 0.65 to 0.9 with their fiber directions substantially orthogonal to the long sides. Is a plate, thickness 1 ~
At 4 mm, tropical products such as Agathis, domestic products such as Ezo pine, larch and cedar, and Soviet products, from Oceania such as radiata pine, North American coniferous wood such as Beetuga, Spruce, Bay pine, Ponderosa pine, Lauan, Celaya, Merranchi. In addition, tropical hardwood such as cottonwood, poplar, aspen, white birch, maple and alder, and domestic hardwood such as Delonoki, honoki and sina are used. The air-dry specific gravity is less than 0.65 because of the wood fiberboard 1,1 and the wood veneer inside it 2,
This is to compensate for the increase in weight and the deterioration in machinability and nailability due to No. 2.

[0018]

4 is a wood veneer 3 having an air-dry specific gravity of less than 0.65.
3 is a wood veneer with an air dry specific gravity of 0.65 to 0.9, the fiber direction of which is arranged substantially parallel to the long side inside 3, and the thickness is 1 to 4 mm,
The same kind of wood as the wood veneers 2 and 2 is used, and when it is located in the center, the neutral axis is used to improve the strength and balance of the base material, and when the side surface is actually machined, doweled, and mortise bonded. This is because the strength is developed.

[0019]

According to a second aspect, the air-dry specific gravity of the first aspect is 0.6.
Specify tropical hard wood veneer instead of 5 to 0.9 wood veneer, and coniferous wood veneer instead of wood veneer less than 0.65 to classify wood veneer to be used. Have been identified. As a result, in the case of a natural wood veneer, a wood veneer that partially exceeds the scope of claim 1 may be included due to the difference in the sampling position, the growth environment, or the variation in the water content.

[0020]

The manufacturing method is the same as the known laminating adhesion of plywood, and the wood fiber board 1 is made with a thermosetting adhesive such as urea, melamine, urea melamine, phenol or resorcinol depending on the required water resistance and strength. , 1 and wood veneer 2,
Whether heat is applied between the layers 2, 3, 3 and 4 via an adhesive,
Once the wood veneers 2,2,3,3,4 are laminated and integrated with the above adhesive, the wood fiberboards 1 and 1 are subjected to two steps by using water-based vinyl urethane, ethylene vinyl acetate adhesive, etc. on the front and back. The wood-based composite substrate A is obtained by dividing and laminating.

[0021]

(Example 1) As an experimental example, a width of 100 m
m, length 1800 mm, thickness 2.7 mm, air-dry specific gravity of 0.
70 (water content 8.6%), flexural strength 420 kgf / cm
Inside the ^second two wood fiber board, each thickness of 1.6m
m, air-dry specific gravity 0.80 (water content 12%), bending strength 13
An Apiton veneer of 00 kgf / cm ² is arranged with its fiber direction substantially parallel to the long side, and a thickness of 3.2 m is provided inside thereof.
m, air-dry specific gravity 0.40 (water content 12%), bending strength 70
A radiata pine veneer of 0 kgf / cm ² is arranged with its fiber direction substantially orthogonal to the long side, and a thickness of 1.6 m is provided inside thereof.
m, air-dry specific gravity 0.80 (water content 12%), bending strength 13
An Apiton veneer of 00 kgf / cm ² is arranged with its fiber direction substantially parallel to the long side, and each layer is thermocompressively integrated with a melamine resin adhesive to have a thickness of 15.8 mm (reduction of thickness due to heat pressure). Generated), specific gravity 0.64, bending strength in the long side direction 68
A wood composite base material of Example 1 of 0 kgf / cm ² was obtained.

[0022]

Example 2 Instead of the wood fiberboard of Example 1, the thickness is 2.5 mm and the air-dry specific gravity is 0.89 (water content is 10).
%), Bending strength of 500 kgf / cm ² of wood fiber board, thickness of 1.6 mm instead of Apiton veneer, air dry specific gravity of 0.72 (water content 12%), bending strength of 1000 kgf /
cm ² of Kapur veneer was used, instead of the radiata pine veneer, the thickness was 3.4 mm, and the air-dry specific gravity was 0.40 (water content 1
2%) and a bending strength of 450 kgf / cm ² except that a cottonwood veneer was used, which was laminated and integrated according to Example 1 to have a thickness of 15.8 mm, a specific gravity of 0.67, and a bending strength of 6 in the long side direction.
40 kgf / cm ² of the wood-based composite substrate of Example 2 was obtained.

[0023]

(Example 3) Instead of the wood fiberboard of Example 1, the thickness is 3 mm and the air-dry specific gravity is 0.76 (water content 8.3).
%), Bending strength of 385 kgf / cm ² of wood fiber board, thickness of 1.6 mm instead of Apiton veneer, air-dry specific gravity of 0.72 (water content 12%), bending strength of 1000 kgf /
cm ² of Kapur veneer, thickness of 3.0 mm instead of radiata pine veneer, air-dry specific gravity of 0.50 (water content 1
2%), and a lauan veneer having a bending strength of 760 kgf / cm ² was used.
1mm, specific gravity 0.69, long side bending strength 620kg
A wood composite substrate of Example 3 with f / cm ² was obtained.

[0024]

COMPARATIVE EXAMPLE 1 Instead of the Apiton veneer of Example 1, a thickness of 1.6 mm and an air-dry specific gravity of 0.5 (water content 12
%), A lauan veneer having a bending strength of 760 kgf / cm ² is used, and a thickness of 3.0 mm is used instead of the radiata pine veneer.
Air-dry specific gravity 0.50 (water content 12%), bending strength 760k
Comparative example 1 having a thickness of 15.4 mm, a specific gravity of 0.60, and a bending strength in the long side direction of 590 kgf / cm ² was obtained by laminating and integrating in accordance with Example 1 except that a lauan veneer having a gf / cm ² was used. It was

[0025]

(Comparative Example 2) Instead of the radiata pine veneer of Example 1, an Apiton veneer having a thickness of 3.2 mm, an air dry specific gravity of 0.80 (water content 12%) and a bending strength of 1300 kgf / cm ² was used. Other than that, according to the first embodiment, laminated and integrated,
Thickness 15.8 mm, specific gravity 0.81, to obtain a comparative example 2 in the long side direction of the bending strength 720kgf / cm ^2.

[0026]

A dry / wet repeated test was conducted for Example 1.2.3 and Comparative Example 1.2 at 40 ° C. 90% RH (7 days) and 15 ° C. 45% (2 days) as one cycle.
When the warp was observed by repeating the cycle, there was no warp that would hinder the use, except that the warp was conspicuous in the comparative example 1 which was slightly warped during the production.

[0027]

Regarding the machinability and nailability of each sample, it was found in Comparative Example 2 that the hardness was remarkable and the workability and handleability were inferior to those of the other samples.

[0028]

[0022]

[0029]

As described above, the wood-based composite substrate of the present invention is
In claim 1, the wood fiberboard of the front and back layers and the wood veneer arranged inside the wood fiberboard which influences the strength and warpage in the long side direction are 0.65.
In the specific gravity range of 0.9 to 0.9, the existence of voids inside both materials is approximated to reduce the difference in absorption of the adhesive during lamination and the difference in migration of moisture during use. The wood veneer having an air-dry specific gravity of less than 0.65, which is arranged inside the wood veneer of No. 9, contributes to weight reduction of the whole and improvement of machinability and nailability.
Moreover, since a wood veneer similar to the wood veneer of 0.65 to 0.9 is located in the same direction in the central portion, it contributes to bending, mouth end strength and balance as a neutral axis.

[0030]

Therefore, the wood-based composite substrate of the present invention is less likely to warp during production or use, has a small weight increase, and is easy to handle such as sawing, cutting edge wear, and nail bending. Become.

[Brief description of drawings]

FIG. 1 is a side view of a wood composite base material A according to the present invention.

[Explanation of symbols]

 A ... Wood composite base material 1 ... Wood fiber board 2, 3, 4 ... Wood single board

Claims (2)

[Claims] 1. An air-dry specific gravity of 0.65 having long front and back layers.
0.9 wood fiberboard, and wood veneers having an air-dry specific gravity of 0.65 to 0.9 are laminated inside each wood fiberboard such that the fiber direction thereof is substantially parallel to the long side of the wood fiberboard. , Inside of which wood veneers each having an air-dry specific gravity of less than 0.65 are laminated so that the fiber direction is substantially orthogonal to the long sides, and further inside the wood veneers having an air-dry specific gravity of 0.65 to 0.9. A wood composite base material in which the fiber direction is laminated and integrated substantially parallel to the long sides. 2. An air-dry specific gravity of 0.65 having long front and back layers.
0.9 wood fiberboard, and tropical hard wood veneer is laminated inside each wood fiberboard in a direction substantially parallel to the long side of the wood fiberboard, and inside each coniferous wood single board. Laminate the plates with the fiber direction substantially orthogonal to the long sides,
Further, a wood-based composite substrate is formed by laminating a tropical hard wood veneer inside and laminating the fiber direction thereof substantially parallel to the long sides.