JPH03106604A - Method for producing oil-treated wood materials - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is an improvement in efficiently applying an oil finish to wood materials and industrially producing oil treated wood materials with excellent decorative appearance and physical properties such as toughness. It's about technology. [Conventional technology] Generally speaking, drying oils such as linseed oil, tung oil, dehydrated castor oil, etc. are rubbed onto the surface of wood materials used for building materials, furniture, etc. to create the natural grain of the wood material. It has been practiced for a long time to improve the stain resistance, water resistance, etc. while making the wet color stand out.

On the other hand, in recent years, as a method for improving wood materials, wood composite materials, so-called W
PC manufacturing is also underway. (Problem to be solved by the invention) However, according to the former method of rubbing a drying oil such as linseed oil onto the surface of a wooden material, the surface of the wooden material hardens after a long period of time due to oxidative polymerization. However, it is difficult to completely cure the inside of the wood, and unhardened oil inside may migrate to the surface due to changes in temperature and humidity during use. It is something that cannot be done.

As a result, the hardened layer easily separates from the surface of the wood material, resulting in decreased durability, and shortcomings of wood, such as long-term water resistance and stain resistance, have not been improved.

On the other hand, the latter method of synthetic resin injection hardening treatment has been produced in large quantities in recent years because it can give wood materials an appearance such as transparency and excellent physical properties such as hardness and abrasion resistance. However, the quality is not stable unless a high viscosity resin liquid is injected and hardened, and the difference in impregnation rate between the spring and autumn wood parts of the wood and the translucency of the resin itself make the wood grain difficult to maintain. This is a problem in which the material becomes transparent and has an artificial, plastic-like appearance, and it is difficult to provide a natural color and texture appearance with an oil finish. In order to solve this problem, the inventors of the present invention have proposed Japanese Patent Application No. 1-2639
), a liquid composition containing a mixture of drying oil fatty acid esters, polymerizable monomers, and polymerization catalysts is impregnated into wood, and We have developed a method to obtain a durable oil finish by causing a curing reaction to integrate with wood materials, but even with this improved method, there are still cases where the curing properties are inferior depending on the wood species and curing conditions.
In addition, the cured product has drawbacks such as significant cloudiness depending on the conditions.

The present invention provides a method for producing an oil-treated wood material that overcomes these problems.

[Means to solve the problem]

In order to achieve the above object, the method for producing an oil-treated wood material of the present invention involves an addition reaction of a polymerizable organic acid anhydride to the hydroxyl group of a higher fatty acid or its ester of a non-drying oil having a hydroxyl group in the molecule. It is characterized by impregnating a wood material with an oil agent containing at least an esterification reaction product, a polymerizable monomer, and a polymerization catalyst as essential components, and causing a curing reaction to occur in the wood material. be.

In the above-mentioned oil agent, the non-drying oil higher fatty acid or its ester is ricinoleic acid, ester of ricinoleic acid, etc., and castor oil is particularly preferred. Examples of polymerizable organic acid anhydrides include maleic anhydride and itaconic anhydride. Polymerizable monomers include aromatic compounds such as styrene, vinyltoluene, and divinylbenzene, and methyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, and 2-hydroxyethyl methacrylate that can be copolymerized with them. Acrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, trimethylolpropane tri(meth)
There are acrylates, etc.

Oils made from mixtures of these generally have low viscosity, easily infiltrate wood, and can be rapidly cured even at relatively low temperatures when a polymerization catalyst is used. As a polymerization catalyst, penzoyl peroxide, t-butyl peroxide, cumene hydroperoxide, dicumyl peroxide, 1.1-bis(t-butylperoxy) 3.3.5-}limethylcyclohexane, butylperoxy Examples include benzoate.

To carry out the method of the present invention, approximately equimolar amounts of a polymerizable organic acid anhydride are subjected to a ring-opening addition reaction under non-dehydrating conditions to a hydroxyl group of a higher fatty acid of a non-drying oil having a hydroxyl group or an ester thereof. , 620 to 60 parts by weight of a polymerizable monomer and 0 parts by weight of a polymerization catalyst based on 80 to 40 M parts of this reactant.
．． A treatment solution is prepared by dissolving 5 to 5 parts by weight, and a wood veneer, columnar wood, or other wood material is immersed in this treatment solution, and the treatment solution is applied to the wood material using a combination of operations such as depressurization and pressurization. The treatment solution-impregnated veneer is then pressurized and heated to harden it.

At this time, the reaction between the higher fatty acid or its ester of the non-drying oil having a hydroxyl group and the polymerizable organic acid anhydride is
Finishing takes 2 to 5 hours at a temperature of 120°C.

For hardening of impregnated wood materials, the heating temperature is 80 to 180℃.
°C, especially 100 to 140 °C, and the pressure is suitably from contact pressure to about 50 kgf/cj.

The time required for curing the treatment liquid impregnated into the wood material varies depending on the amount of curing agent, temperature, thickness of the wood material, etc., but about 5 minutes to 120 minutes is sufficient.

[For production]

An oil agent consisting of a higher fatty acid ester of a non-drying oil having a hydroxyl group or a reaction product of the ester and a polymerizable organic acid anhydride, and a mixed liquid composition of this reaction product, polymerizable monomers, and a polymerization catalyst. , it has a low viscosity and easily penetrates into the minute voids in the wood, and the oil that penetrates into the wood turns the wood wet and colored, and the treatment liquid hardens within the minute voids in the wood and prevents changes in temperature and humidity. It does not leach out even when exposed to liquids or water, exhibits good stain resistance and water repellency over a long period of time, and maintains the above-mentioned appearance.

In addition, the treatment agent that penetrates into the microscopic voids of the wood material and hardens it provides toughness that is not found in WPC, which is obtained by injection hardening of conventional unsaturated polyester or methacrylic resin.
Machinability is also improved.

Furthermore, the above-mentioned Japanese Patent Application Laid-open No. 1-2-2 filed earlier by the inventors of the present application
A much faster curing speed is obtained than that using drying oil fatty acid esters and polymerizable monomers as described in No. 6390, the cured resin does not become cloudy, and the yield of the resin is good. The reason why it exhibits better physical properties and a deeper appearance than conventional WPC is that the resin liquid for conventional WPC has a high viscosity and has a low affinity with wood grain. Compared to the case where the resin is mainly formed within the relatively large pores of wood, in the treatment liquid of the present invention, the low-molecular weight substance penetrates into the microscopic pores of the wood, and the side chain carboxyl groups intertwine with the wood structure, resulting in good adhesion and hardening. Moreover, since it cures quickly, the impregnating liquid is not pushed out during compression curing, and the yield of the resin is thought to be improved.

Hereinafter, the present invention will be explained in more detail with reference to Examples.
These examples do not include all aspects of the invention. [Example 1] Castor oil 1. 100 parts by weight of maleic anhydride was mixed with 100 parts by weight and heated while stirring until the temperature reached 100 parts by weight.
After reaching ℃, the mixture was kept at the same temperature for 3 hours while stirring to obtain a uniform viscous liquid. 600 parts by weight of this viscous liquid, 350 parts by weight of styrene monomer, 50 parts by weight of trimethylolpropane trimethacrylate.
Parts by weight, 0.2 parts by weight of hydroquinone, and 10 parts by weight of penzoyl peroxide were prepared and stirred well to uniformly dissolve them to obtain a treatment liquid.

An oak veneer and a teak veneer with a thickness of 3 mm and a side of about 10 cm are impregnated with this treatment solution, held under a reduced pressure of 30 torr for about 60 minutes to deaerate, and returned to normal pressure for about 2 hours. The treatment solution was allowed to penetrate into these wood veneers by leaving it for a while. After that, remove the excess resin liquid adhering to the wood veneer, and heat it to 120°C.
, Pressed under the conditions of heating and pressure of 10 kgf/cd,
These conditions were maintained for 10 minutes to allow curing. Then, it was cured at normal pressure and 100° C. for 1 hour.

The content of oil that is impregnated and hardened into wood veneers is approximately 65% for oak veneers and approximately 55% for teak veneers. It had excellent workability. [Example 2] 850 parts by weight of castor oil and 150 parts by weight of maleic anhydride were blended, heated while stirring, and after the temperature reached 120°C, the same temperature was maintained for about 2 hours to allow the reaction to occur while stirring. A yellowish brown viscous homogeneous liquid was obtained. This viscous liquid 520
parts by weight, 400 parts by weight of styrene monomer, 80 parts by weight of trimethylolpropane trimethacrylate, 0.2 parts by weight of hydroquinone, and 15 parts by weight of 1.1bis-(1-butylperoxy)3.35-}limethylcyclohexane. Then, stir well to obtain a uniformly dissolved treatment solution. Next, a 10cm square Douglas fir veneer with a thickness of 0.6s+a was immersed in the treatment solution, degassed under reduced pressure of 30 torr for 60 minutes, and then the treatment solution penetrated into the veneer for about 2 hours at normal pressure. After that, excess processing liquid was removed, and then it was heated to 130
When the treatment solution-impregnated veneer was cured at ℃ for 20 minutes under a pressure of 10 kgf/c-, the amount of resin impregnation was 130%, and the veneer was rich in toughness with beautiful patterns in the earlywood and latewood areas. An oil treated veneer was obtained.

This oil treated veneer is pasted on 15ms thick plywood and JA
Water resistance tests, cold and heat tests, etc. were conducted in accordance with the S special plywood standard, and these performances were also extremely excellent. [Example 3] 600 parts by weight of the mustard oil/maleic anhydride addition reaction product combined in Example 2, 300 parts by weight of styrene monomer, 100 parts by weight of trimethylolpropane trimethacrylate, 0.1 part by weight of hydroquinone monomethyl ether A treatment liquid was obtained by mixing 10 parts by weight of Percure 10 (manufactured by Nippon Oil & Fats Co., Ltd.) and stirring well to uniformly dissolve the solution.

The viscosity of this treatment liquid is approximately 70 cps (25°C),
Gel time at 80°C is 10 minutes, minimum curing time is 18
At 30 minutes, the maximum exothermic temperature was 146°C.

Next, 10 pieces of Douglas fir veneer with a thickness of 0.6 m + s and a square of 10 cm + w, and 1 piece of quince veneer with a thickness of 1.5 mm and a square of IQ cm.
7 sheets were placed in a vacuum container and degassed under a reduced pressure of 20 torr for 1 hour, then the above treatment liquid was introduced into the container, the pressure returned to normal pressure, and then immersed for 1 hour under a pressure of 10 kgf/cd. A resin-injected veneer was obtained.

When this resin-injected veneer was drained to recover excess resin, the recovered resin liquid had a pot life of more than two weeks at 30°C and had excellent storage stability.

The resin-injected veneer is then pressed at 120°C with a weight of 10 kg.
It was cured by heat and pressure treatment for 15 minutes under pressure of f/c+a. As a result, the amount of resin impregnation was 125% in the Douglas fir veneer and 50% in the Japanese quince veneer, and oil-treated veneers with a beautiful wet feel and high toughness were obtained.

Normally, radical-curing resins have excellent curability, as they cure well even in quince, which tends to suffer from poor curing due to the extracted substances in the wood.

[Example 4] 500 parts by weight of the castor oil/maleic anhydride addition reaction product prepared in Example 2, 350 parts by weight of styrene monomer, 100 parts by weight of trimethylolpropane trimethacrylate, 50 parts by weight of 2-hydroxyethyl methacrylate. Department,
0.1 parts by weight of hydroquinone and 10 parts by weight of penzoyl peroxide were mixed and stirred well to uniformly dissolve them to obtain a treatment liquid.

Next, with a thickness of 0.6 mm, 10 co + square bay mat veneer 1
Ten oak veneers and ten Japanese quince veneers each having a thickness of 1.5 mm and a square size of 10 cm were subjected to injection hardening treatment in the same manner as in Example 3 using the above treatment solution to obtain oil-treated veneers.

The amount of resin impregnated in the oil-treated veneer thus obtained was 120% for Beimat single IIi, 70% for oak veneer, and 50% for quince veneer.
It had good hardenability, high toughness, and excellent machinability.

In addition, each of these oil-treated veneers was attached to 15A thick plywood and subjected to water resistance tests, cold and heat tests, etc. in accordance with the LAS special plywood standard, and these performances were also extremely excellent. Ta.

[Comparative example]

250 parts by weight of dehydrated castor oil, 600 parts by weight of 2-ethylhexyl methacrylate, 00 parts by weight of trimethicol propane trimethacrylate, 50 parts by weight of maleic anhydride, 5 parts by weight of benzoyl peroxide, dicumyl peroxide A processing solution was prepared in which parts by weight of 1O were dissolved.

On the other hand, after drying each veneer of Douglas fir, oak, and birch with a thickness of 1.5 mm at 105°C for 2 hours, these veneers were immersed in the treatment solution for 1.5 hours, and then heated under reduced pressure at room temperature.
Each veneer was left to stand under normal pressure for 15 hours to be impregnated with the treatment solution.

Next, each veneer impregnated with the treatment liquid was covered with a Tetron film, and then treated at 120° C. for 2 hours under contact pressure to harden the impregnating liquid.

In this way, the impregnation rate of the treatment agent impregnated and hardened into each veneer was 95% for Douglas fir, 73% for oak, and 120% for birch.
It has a cloudy appearance and takes a long time to harden, making it difficult to apply it to industrial production.

〔effect〕

As described above, the method for producing an oil-treated wood material of the present invention includes:
An esterification reaction product obtained by addition-reacting a polymerizable organic acid anhydride to the hydroxyl group of a non-drying oil fatty acid or its ester having a hydroxyl group in the molecule, a polymerizable monomer, and a polymerization catalyst are essential precepts. It is characterized by impregnating a wood material with an oil agent and causing a curing reaction in the wood material. Therefore, the treatment liquid consisting of the oil agent has a low viscosity (50
0 cpS or less), and since it is mainly composed of castor oil and its fatty acids, which are natural products, it easily penetrates into the minute voids of wood and produces the same wet color as when treated with an oil agent. In other words, wood treated with an oil agent can be obtained in a very short period of time, and it is superior to the method using the drying oil fatty acid esters that the inventors developed earlier. The present invention using drying oil fatty acid esters is extremely advantageous industrially.

In addition, in the present invention, the treatment liquid hardens within the microscopic voids in the wood material, so it does not leach due to changes in temperature or humidity or water, and exhibits good water repellency and stain resistance over a long period of time. In addition, it can provide flexibility and toughness that cannot be obtained with conventional unsaturated polyester or methacrylic WPC, and also has good cutting and nailing properties. It is.

As described above, according to the method of the present invention, it is possible to industrially produce oil-treated wood materials that are finished with an oil agent, have excellent decorative appearance, and have good water resistance, stain resistance, and toughness. It can be easily produced in large quantities and can be widely used for various building materials, furniture, etc.

Claims (1)

[Claims] (1) An esterification reaction product obtained by adding a polymerizable organic acid anhydride to the hydroxyl group of a higher fatty acid or its ester of a non-drying oil having a hydroxyl group in the molecule, a polymerizable monomer, and a polymerizable monomer. A method for producing an oil-treated wood material, which comprises impregnating a wood material with an oil agent containing a catalyst as an essential component and causing a curing reaction to occur in the wood material.