JPH0596512A - Manufacture of modified wood - Google Patents

Abstract

(57) [Summary] [Purpose] To facilitate the injection of a synthetic resin solution into a wood material and efficiently produce a resin-injected wood material having excellent cosmetic properties. [Structure] Injecting ozone-containing gas into a wood material to infiltrate the wood material to invade the wood cell tissue with ozone to form innumerable micropores in the cell wall to facilitate injection of a synthetic resin solution, and then a synthetic resin Liquid injection hardening process is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a synthetic resin liquid impregnating property and productivity for wood materials when manufacturing synthetic resin-injected wood used as decorative materials such as flooring materials, wall materials, and furniture. The present invention relates to a method for producing modified wood capable of improving cosmetic properties.

[0002]

2. Description of the Related Art In order to improve the strength, durability, and cosmetic properties of wood materials, a resin injection treated wood material (hereinafter referred to as WP) has been conventionally used by injecting and curing a synthetic resin liquid into the voids in the wood material.
A manufacturing method referred to as C) is known. However, the wood material is a natural product, and the state of the cell tissue varies depending on the tree species and the degree of growth, and even if the wood material is impregnated with a synthetic resin solution under certain conditions, the impregnability varies considerably. It will be.

For this reason, the resin impregnation inhibitory substance in the wood material is previously extracted with a chemical agent or the wood structure is mechanically destroyed by insizing or the like to facilitate the injection of the synthetic resin liquid. ing. In addition, applicants are specially fair 2
As described in Japanese Laid-Open Patent Publication No. 37842, the wood material is also preliminarily eroded by decaying bacteria to improve the impregnation property of the resin liquid.

[0004]

However, in the method of extracting the resin impregnation inhibitor in the woody material with a chemical or the like, not only is it time-consuming to wash and dry the chemical, but the working environment deteriorates, and mechanical wood is used. The tissue destruction method requires adjustment of the pressing force against the wood material and the shape of the tip surface of the pressing machine, and in addition, the shape of the wood material to be treated may not be able to uniformly destroy the wood tissue, resulting in the wood material being destroyed. However, there is a problem that the shape of is limited.

Further, in the method of treating a wood material with a rot fungus, it takes a long time for the treatment, and side effects such as discoloration and darkening of the wood material occur, impairing the cosmetic properties of the obtained WPC. was there. It is an object of the present invention to provide a method for producing a modified wood, which solves such problems and is excellent in resin injection processability and workability and can obtain a beautiful WPC.

[0006]

In order to achieve the above-mentioned object, a method for producing modified wood according to the present invention comprises injecting an ozone-containing gas into a wood material to corrode the wood material with ozone in the ozone-containing gas. After that, the synthetic resin liquid is impregnated and cured in the wood material. According to the second aspect of the present invention, after the ozone-containing gas is injected into the wood material, the synthetic resin liquid is impregnated into the wood material, and the impregnated resin liquid is cured in a state where the wood material is pressed. It is characterized by that.

[0007]

[Function] When the wood material is impregnated with the ozone-containing gas before the wood material is impregnated with the synthetic resin liquid, the molecular chains of the wood tissue are randomly divided by the ozone in the gas, and innumerable in the cell wall. Micropores are generated and the porosity of the cell wall is increased. Then, when this wood material is impregnated with the synthetic resin liquid, even if the resin liquid has a high viscosity, the impregnation is promoted even inside the wood material. Further, even in the case of a synthetic resin liquid diluted with a solvent, the evaporation of the solvent is promoted after the impregnation, so that the uneven distribution of the resin is reduced.

The tissue of the wood material is attacked by ozone to deteriorate the original hardness, strength, scratch resistance, etc. of the wood material, but not only is it reinforced by the subsequent injection of the synthetic resin liquid, but the physical properties thereof are enhanced. In addition, the wood material is oxidatively decolorized by ozone, and it can be processed without impairing the original color and cosmetic properties of the wood material such as white wood, grain of wood, etc., white wood tone and injection, coloring with impregnated resin, The color tone is as it is, and the cosmetic properties are improved.

Further, even when the surface of the wood material is previously formed into an uneven surface or the wood material is subjected to a three-dimensional processing, the erosion action of the wood cell tissue by the ozone-containing gas is surely performed. In addition, the impregnation of the synthetic resin liquid is promoted in the same manner as described above, and uniform resin impregnation treatment is performed.
Furthermore, the resin impregnation treatment of only the surface layer of the wood material is possible by adjusting the concentration and pressure of ozone in the ozone-containing gas that is injected and permeated into the wood material, the injection time, and the like.

Further, according to the method of claim 2 of the present invention, since the synthetic resin liquid is cured in a state where the synthetic resin liquid is impregnated after the impregnation treatment with the synthetic resin liquid, the wooden material is pressurized. The material is compressed and deformed, the surface hardness is increased, the wood grain is compacted, and a high-quality makeup is developed. In addition, surface embossing with a concavo-convex shaped material is possible.

[0011]

EXAMPLES Next, examples of the present invention will be described in detail. First, wood materials such as lumber products and veneers, preferably wood materials dried to a fiber saturation point (water content of about 30%) or less. After being placed in a pressure container, a gas containing ozone is supplied into the container to inject the ozone-containing gas into the wood material. In addition, it is preferable that the wood material contains water because the ozone gas activates the water content in the wood and improves the treatment effect of the ozone-containing gas.

The ozone-containing gas may be injected into the wood material by pressurization, or may be injected by a reduced pressure method. The ozone-containing gas is a mixture of air or an inert gas such as nitrogen gas with an appropriate amount of ozone gas, and the concentration of ozone is adjusted by the amount of air or nitrogen gas mixed. The ozone concentration and injection conditions are adjusted according to the permeation of ozone into the wood material and the treatment depth, and the ozone concentration is 5% or less, preferably 1% or less.

On the other hand, with respect to the injection conditions, the injection pressure is from normal pressure to 20 at either room temperature or warming condition.
Within the range of kg / cm ² =, and the injection treatment time is set to several seconds to several hours depending on the ozone concentration and pressure. In both cases, the pressure increases and the injection time increases as the wood material is treated to the inside. To adjust.

FIG. 1 is a simplified diagram of a device for generating and injecting ozone-containing gas to be injected into a wood material. The ozone generator 1 is connected to a suction side of a pressure pump 3 through a pipe 2, and the pressure pump 3 is connected to the suction side. Is connected to a pressure vessel 5 through a pipe 4, ozone generated in the ozone generator 1 is sent to the pressure pump 2 at normal pressure, and air or nitrogen is supplied into the pressure pump 3. Gas is supplied and mixed with ozone gas. At this time, a mixed gas having a desired ozone concentration is adjusted by changing the supply amount of air or nitrogen gas.

The ozone-mixed gas mixed and adjusted in the pressurizing pump in this manner is supplied to the pressure vessel 5 at a desired pressure, and ozone is injected into the wood material contained in the vessel 5. Is to do. The wood material may be lumber, lumber, white oak, zelkova, or other lumber product, processed product, plywood, veneer, or the like, and any species such as conifer and hardwood.

When ozone-containing gas is supplied into the pressure vessel 5, the gas comes into contact with the surface of the wood material in the vessel and permeates and is injected into the material according to the magnitude of the pressure. Is invaded and its molecular chains are randomly divided and decomposed, resulting in numerous micropores in the cell wall of wood. As a result, the porosity inside the wood increases.

After the wood material is treated with ozone in this manner, the wood material is then impregnated with the synthetic resin liquid. As the synthetic resin liquid, a radical polymerization type resin liquid of a simple substance or a complex composed of unsaturated polyester, isocyanate, acrylic, MMA, styrene or the like or a resin liquid obtained by appropriately diluting the resin liquid with an organic solvent such as xylene, Alternatively, it may be any synthetic resin liquid such as condensation type resin liquid such as fail, melamine, urea, etc., and further suitable plasticizer, colorant, curing accelerator, etc. for these resin liquids as necessary. May be added.

The method of impregnating the synthetic resin liquid is the dipping method,
Known injection methods such as depressurization method and depressurization / pressurization method in the pressure vessel may be used alone or in combination. In this way, when the wood material is impregnated with the synthetic resin solution, as described above, the wood material has a large number of minute pores formed in its cell wall by the ozone injection treatment in advance, and the porosity is increased. Is easily and uniformly performed over the entire treatment depth, and the synthetic resin liquid fills every corner of the cell void portion in the material.

After impregnating the synthetic resin liquid into the wood material,
Immediately or through a solvent volatilization step, the resin liquid-impregnated wood material is heated without pressurization, or is heated in a compressed state to cure the impregnated resin liquid to obtain WPC. The solvent volatilization step before the heat treatment is for preventing the wood material from warping or exploding. As a method of curing the impregnated resin liquid without pressurizing the wood material, for example, the wood material impregnated with the resin liquid may be contact-heated by a heating plate, high-frequency heating may be used, or a heating source may be provided inside. There is a method of placing it on a heavy jacket and performing indirect heating.

On the other hand, as a method for carrying out the heat curing treatment in the pressed state, a hot press is used. In this case, the wooden material impregnated with the resin liquid is 1 / th of the original material thickness due to the pressing pressure.
It is compressed to a thickness of 20 to 1/2 and consolidated to change the surface makeup and further improve physical properties such as strength, abrasion resistance, and dimensional stability. Since the cellular structure of the wood material is weakened by the ozone treatment, it can be easily compressed to the above thickness without applying a particularly high pressing pressure.

Next, specific examples and comparative examples of the present invention will be shown. Example 1 A hemlock veneer having a thickness of 3 mm and a water content of 15% was placed in a pressure vessel, and then air containing 5000 ppm of ozone concentration was applied to the hemlock veneer at room temperature at a pressure of 4 kg / cm ² =. It was pressurized and injected for 2 hours. In this way, the sapwood veneer veneer subjected to ozone treatment was decolorized in both the sapwood part and the heartwood part. Then, this treated veneer was immersed in an MMA resin solution containing 0.3% by weight of benzoyl peroxide for 30 minutes to obtain a resin-impregnated veneer having a resin injection rate of 28% based on the total dry weight. After wrapping this veneer with aluminum foil so that the resin liquid does not scatter, it is heated under normal pressure with hot air at 70 ° C for 3 hours,
The impregnating resin liquid was cured. Then, when the surface of the veneer was sandered, a white WPC with a beautiful makeup was obtained which had an appearance surface with no resin injection unevenness.

Comparative Example 1 A hemlock veneer veneer having a thickness of 3 mm and a water content of 15% was immersed in the same MMA resin solution as in Example 1 for 30 minutes without ozone treatment. The resin injection rate was based on the total dry weight. Yielded a 12% resin-impregnated veneer. After wrapping this veneer with aluminum foil so that the resin liquid will not scatter, use hot air at 70 ° C for 3
The impregnated resin liquid was cured by heating for a period of time, and then the surface of the veneer was sandered. As a result, a WPC having a cosmetic property in which uneven resin injection was observed was obtained.

Example 2 A Hagatsuga plate having a thickness of 4.5 cm and a water content of 12% was housed in a pressure vessel, and then air containing 7,000 ppm of ozone concentration was applied to the Hakkoga plate at a room temperature of 5 kg / cm ² = It was pressurized and injected with the pressure of 2 hours for 2 hours. In this manner, the sapwood and heartwood parts of the ozone-treated hemlock board were decolorized. Then, after sealing the resin so that the resin liquid does not enter from the mouth of this treated plate, the plate is put in a vacuum kettle under a reduced pressure of 50 Torr for 30 minutes, and further under normal pressure for 1 hour. When the same MMA resin solution as in Example 1 was injected, a resin-impregnated plate having a resin injection rate of 33% based on the total dry weight was obtained. This plate was wrapped with an aluminum foil so that the resin liquid would not scatter, and heated under normal pressure with warm air at 60 ° C. for 12 hours to cure the impregnated resin liquid. Then, when the surface of the plate was sanded, a white WPC with a beautiful makeup was obtained which had an appearance surface with no resin injection unevenness.

Comparative Example 2 After sealing the mouth of a hemlock gauze plate having a thickness of 4.5 cm and a water content of 12%, the plate was put in a vacuum oven and placed under a reduced pressure of 50 Torr for 30
Example 1 under the condition of 1 minute under atmospheric pressure and 1 hour under normal pressure
When the same MMA resin solution was injected, a resin-impregnated plate having a resin injection rate of 13% based on the total dry weight was obtained. This plate was wrapped with an aluminum foil so that the resin liquid would not scatter, and heated under normal pressure with warm air at 60 ° C. for 12 hours to cure the impregnated resin liquid. After that, when the surface of the plate was sandered, it showed a cosmetic property in which uneven injection of resin was observed.

Example 3 A thickness of 4.5 cm and a moisture content of 12% was applied to the above-mentioned example 2.
After performing ozone treatment and MMA resin injection treatment under the same conditions as above to obtain a resin-impregnated plate with a resin injection rate of 33% based on the total dry weight, this plate was subjected to 5 kg / cm ² = The impregnated resin liquid was cured by hot pressing at 100 ° C. for 20 minutes under pressure. Then, when the surface of the plate was sanded, a white WPC with a beautiful makeup was obtained which had an appearance surface with no resin injection unevenness. Also, this W
The abrasion resistance of PC is measured by taper abrasion tester # 180, 15
Brennel hardness was
It was 3.75 kg / mm ² =.

Comparative Example 3 The above-mentioned Comparative Example 2 was prepared by using the above-mentioned hemlock sheet having a thickness of 4.5 cm and a water content of 12%.
Under the same conditions as above, the MMA resin solution was injected to obtain a resin-impregnated plate with a resin injection rate of 13% based on the total dry weight, and then this plate was hot-pressed under a pressure of 5 kg / cm ² = 10%.
The impregnated resin liquid was cured by hot pressing at 0 ° C. for 20 minutes. After that, when the surface of the plate was sandered, it showed a cosmetic property in which uneven injection of resin was observed. Also, this WPC
The abrasion resistance of taper abrasion tester # 180, 20μm
Brennel hardness of 2.01
It was kg / mm ² =.

[0027]

As described above, according to the method for producing modified wood of the present invention, after the ozone-containing gas is injected into the wood material (the wood cell wall is eroded by the ozone in the ozone-containing gas), it is synthesized. Since the wood material is characterized by being impregnated and cured with a resin liquid, the cell walls of the wood material are eroded and destroyed by ozone gas, and innumerable micropores can be formed in the cell wall. The synthetic resin liquid can be smoothly and surely impregnated into the wood material, and even if the synthetic resin liquid has a high viscosity, the impregnation is promoted to the inside of the wood material that has been subjected to the ozone treatment, and the resin injection treatment is efficient. It can be performed well and uniformly. Further, the ozone gas processing device is simple and can be processed without causing pollution.

Furthermore, although the tissue of the wood material is attacked by ozone, the original hardness, strength, scratch resistance, etc. of the wood material are deteriorated.
It is not only reinforced by the subsequent injection of synthetic resin liquid, but of course the injection of ozone gas causes the wood material to oxidize and decolorize to develop a white wood color, and to prevent darkening and to treat it without impairing its cosmetic properties and grain. Therefore, it is possible to make Shiraki tone, injection, coloring with impregnating resin, toning,
It is possible to obtain WPC having excellent cosmetic properties.

Further, even when the surface of the wood material is formed into an uneven surface or the wood material is subjected to three-dimensional processing, the erosion action of the wood cell tissue by the ozone mixed gas is surely performed. Along with the above, it is possible to accelerate the impregnation of the synthetic resin liquid, which enables a uniform resin impregnation treatment.In addition, the concentration and pressure of ozone in the ozone-containing gas to be injected and permeated into the wood material, the injection time, etc. By adjusting it, it becomes possible to consolidate only the surface layer of the wood material by the resin impregnation treatment.

When the resin solution is hardened after the synthetic resin solution is impregnated, since the tissue of the wood material is weakened by the ozone gas as described above, the wood material is pressed with a desired pressure. By tightening, the wood material can be easily compressed and deformed, so that the surface hardness is increased and the wood grain is compacted to obtain a high-grade cosmetic property. It is possible to easily obtain and obtain a wide variety of WPC.

[Brief description of drawings]

FIG. 1 is a simplified diagram of an ozone mixing gas generation / injection device to be injected into a wood material.

[Explanation of symbols]

 1 Ozone generator 3 Pressure pump 5 Pressure vessel

Claims (2)

[Claims] 1. A reforming method comprising injecting an ozone-containing gas into a wood material to cause the wood material to be eroded by ozone in the ozone-containing gas, and then impregnating and hardening the synthetic resin liquid into the wood material. Wood production method. 2. A method of injecting an ozone-containing gas into a wood material to erode the wood material with ozone in the ozone-containing gas, impregnating the wood material with a synthetic resin liquid, and pressing the wood material A method for producing modified wood, which comprises curing an impregnated resin liquid.