JPH0818289B2 - Modified wood - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention does not impair the aesthetic properties of the wood material by chemically treating the wood material and simultaneously curing the polymer compound in the voids of the wood material. The present invention relates to modified wood with improved durability, hardness and toughness.

[Prior art and its problems]

There are two major methods to combine wood materials and synthetic resins: a method of filling the voids in the wood materials with a polymerizable substance (so-called WPC), and oxides such as hydroxyl groups in the wood material components. There is a method called etherification or esterification by reacting a compound or acid anhydride (so-called chemically modified wood).

There are various types of the above-mentioned polymerizable substances and chemical modifiers, and at present, research on epoxy compounds having a strong chemical bond from the viewpoint of durability and physical property stability is under way. That is, in the former WPC, an epoxy acrylate is impregnated in wood and cured, and it is disclosed in JP-A-60-147303, but the epoxy acrylate has a high viscosity in the prepolymer state and is woody. It is difficult to inject it into the material, and it is necessary to separately dilute it with a solvent or the like having a low affinity for wood components such as styrene and to inject it, and it is difficult to react with hydrophilic wood components. Therefore, most of the resin is only physically filled as a copolymer in the voids in the wood material, the hardness is increased, but because the adhesion to the wood tissue is poor, toughness, flexibility becomes small, There have been problems that cracks and whitening occur and the workability of cutting agents deteriorates.

On the other hand, some of the latter chemically modified woods react epoxy compounds with hydroxyl groups in woody materials as in Japanese Patent Application No. 59-9041. The epoxy compounds are glycidyl ether type with bisphenol A-epichlorohydrin. It is possible to finally form a chemical bond with wood by kneading with a solid or high-viscosity small piece of wood such as wood powder, performing a roll operation, and hot pressing after forming. Therefore, it is difficult to impregnate a wood block or a wood thin plate, let alone chemically modify with a hydroxyl group in wood components in wood, and there is a drawback that it cannot be modified without impairing the cosmetic properties and processability of wood. there were.

Therefore, the inventor has a method of injecting and solidifying a polymerizable substance after chemical modification in advance (JP-A-60-242002).
Invented to obtain a modified wood excellent in stain resistance and dimensional stability, but it required a two-step treatment, which was problematic in terms of productivity.

〔Purpose〕

The present invention eliminates such drawbacks of conventional technology, and is highly durable and stable, and does not lose the texture of wood.
It is an object to provide modified wood that is excellent in reactivity and has been chemically modified and WPC simultaneously at low cost.

[Means for solving problems]

In order to solve the above problems, the present invention involves chemically modifying an active group such as a hydroxyl group in a wood material component with an epoxidized higher fatty acid ester.

The epoxidized higher fatty acid ester and the polyvalent amine compound are polymerized and cured in the voids in the wood material.

 Is adopted as a technical means.

[Operation] The treatment liquid used in the present invention has a low molecular weight and a low viscosity, and easily penetrates into the wood material without using a solvent that hinders the affinity of the wood material with the active groups.

Since the polyvalent amine compound in the treatment liquid has the action of swelling the wood material, it expands the microscopic voids of the wood material and facilitates contact between the active groups such as hydroxyl groups in the wood material component and the epoxidized higher fatty acid ester. To increase reactivity.

The epoxidized higher fatty acid ester is chemically modified by reacting with an active group such as a hydroxyl group in the wood material component, and at the same time, the epoxidized higher fatty acid ester and the polyvalent amine compound are polymerized in the wood material.

The epoxidized higher fatty acid ester reacts with the wood component, and it becomes as if a lubricant entered between the wood components, and flexibility and toughness are imparted.

The polymer compound of the epoxidized higher fatty acid ester and polyvalent amine compound solidified in the voids of the wood becomes as if it rubbed in oil and fat, and it exhibits water repellency like an oil finish without using a plasticizer as in the past. It has a deep wet color appearance with less fluffing. In addition, the pressure resistance is also improved.

Since the polymer compound is chemically bonded to the wood component at the side chain, the polymer compound does not elute with water or alcohol and has good durability.

In the production of this modified wood, chemical modification, resin injection and reaction within the material are completed in one operation, so productivity is good, and by-products are not generated during the reaction, and the treatment liquid Since all of them react in the material, it is not necessary to remove excess treatment liquid or wash it.

〔Example〕

 Hereinafter, the present invention will be described in detail.

As a result of various studies on modified wood, when a wood-based material was impregnated in a mixture of epoxidized higher fatty acid ester and polyvalent amine compound, the mixture easily penetrated into the wood-based material and the impregnated material was heated. Then, the epoxy groups are activated and react with the active groups of the wood material, and at the same time, they also react with the amine compound to cure together with the wood material. as a result,
The present invention has been completed by finding that there is no bad odor or leaching of low-molecular compounds and that the wood texture is sufficiently retained. That is, the present invention is characterized in that a wood-based material is impregnated with a mixed liquid of an epoxidized higher fatty acid ester and a polyvalent amine compound to react with each other, and is solidified together with the wood-based material. Modified WPC Modified wood.

Generally, the reaction between the epoxy compound and the amine proceeds at room temperature, but the mixed solution of the epoxy compound used in the present invention is relatively stable at room temperature, the curing reaction starts by heating, and the cured product is rich in toughness and abrasion resistance. Becomes Further, the polyvalent amine compound rarely remains unreacted, so that the color stability is excellent.

Wood-based materials that can be used in the present invention are block-shaped, plate-shaped,
It may be in any form such as chips and powders, but the effects of the present invention can be remarkably utilized in blocks, plates, etc. Particularly, in terms of workability, productivity and economy, thin wood plates can be used. Is preferred. In any form, in order to keep the properties of the cured product of the reaction agent constant, it is preferable that the water content in the wood be as constant as possible (water content is 10% or less). Epoxidized higher fatty acid esters that can be used include epoxidized linseed oil, epoxidized soybean oil and other triglycerides, and linseed oil fatty acid, soybean oil fatty acid and other unsaturated higher fatty acid monoester epoxidized higher fatty acid There are esters and the like, which have low viscosity and high reactivity with a hydroxyl group and the like, and these can be used alone or in a mixture. Also, glycidyl ethers of bisphenols, phenol novolacs, glycidyl ethers of cresol novolacs, glycidyl phenols, allyl glycidyl ethers, glycidyl methacrylates, and other coloring agents can be used in combination within the range that does not impair the impregnation into woody materials. .

Next, the polyvalent amine compound is metaphenylenediamine,
Incorporate a polyamine compound such as 4.4'-diaminodiphenylmethane, 4.4'-diaminodiphenylsulfone or polyethyleneimine.

The embodiment of the present invention depends on the morphology of the wood material, but basically, the wood material to be treated is held at a constant water content as industrially possible (for example, 0.2 to 10% water content) as an epoxy resin. The mixture is placed in an impregnation tank containing a mixed liquid of a higher fatty acid ester and a polyvalent amine compound, and impregnation is performed by depressurization, normal pressure, pressurization, or a combination thereof, for example, repeated reduction-pressurization. The polyvalent amine compound may be impregnated into the woody material in advance and then impregnated with the epoxidized higher fatty acid ester. Impregnation is carried out until the required amount is reached, and when the wooden material is block-shaped or plate-shaped, wipe the surface impregnated material as it is, or cover it with release paper and heat it at 60-150 ° C in an oven, etc. Pressing and heating with a press will complete in a few minutes to a few hours. It is also possible to continuously heat and solidify with a continuous curing device for paints and the like. The product here has the appearance of a beautiful, soothing, oily finish.

Hereinafter, the present invention will be described in more detail by way of examples, but these do not include all of the present invention.

(Example 1) 1 sheet of 10 Baytsuga veneer having a thickness of 1.5 mm, a width of 100 mm and a length of 100 mm
It was dried at 05 ° C for 2 hours to adjust the water content to 2%. Separately, to 500 g of epoxidized soybean oil (containing 6.9% of oxirane oxygen) was added 1/2 mol equivalent of 4.4'diaminodiphenylmethane of the epoxy by heating and dissolving at 60 ° C to adjust the impregnating solution, and decompressing the veneer. Impregnation was carried out. The impregnation rate was about 120%. The impregnated veneer was treated at 140 ° C. for 3 hours to obtain a treated veneer. The treated veneer had a slightly yellowish but beautiful wood grain, was as flexible and tough as untreated raw wood, and had a sharp cutting surface with a saw or knife, and was excellent in workability. The beauty of the wood grain can be easily maintained by polishing the surface, and it has characteristics that conventional WPC does not have.

(Example 2) Ten cover veneer sheets having a thickness of 1.5 mm, a width of 100 mm, and a length of 100 mm were 105 ° C.
After drying for 2 hours, the water content was adjusted to 3%. Separately, to 500 g of epoxy linseed oil (containing 9.2% of oxirane oxygen), 1/3 molar equivalent of 4.4'diaminodiphenylmethane of the epoxy is heated and melted at 60 ° C to add an impregnating liquid, and the above veneer is depressurized under reduced pressure. Impregnated in. The impregnation rate was about 130%. The impregnated veneer was treated at 140 ° C. for 3 hours to resinize the impregnating liquid to obtain a treated veneer. The treated veneer is finished in a slightly reddish brown color, has a beautiful mahogany appearance, can be polished to maintain its beauty, requires no painting, and has excellent slipperiness while at the same time being a saw. A sharp cutting surface was obtained with a knife, etc. and the workability was also good.

In addition, the impregnating liquid solidified into an oil and fat when stored at room temperature of 20 ° C, but was easily melted by heating at 30-40 ° C,
It had a pot life of one month or more and had an advantage in industrial production.

〔effect〕

According to the present invention, as described above, an epoxidized higher fatty acid ester is chemically modified to an active group such as a hydroxyl group in a woody material component, and the epoxidized higher fatty acid ester and the polyvalent amine compound are mixed in the voids in the woody material. Although it is a modified wood that has been polymerized and hardened, unlike conventional glycidyl ether type epoxies, it uses an epoxidized higher fatty acid ester that is an internal olefin epoxide, so it has high reactivity with active groups such as hydroxyl groups in wood components, It is easily chemically modified and polymerized with a polyvalent amine compound in the material to be solidified and integrated in the voids. In addition, since the polyvalent amine compound in the treatment liquid has an action of swelling wood, it expands the microscopic void spaces of the wood material to prevent contact between the active groups such as hydroxyl groups in the wood component and the epoxidized higher fatty acid ester. It facilitates the function and enhances reactivity and toughness.

In addition, the above-mentioned filling treatment agent has a low molecular weight and a low viscosity, and it is not necessary to use a solvent that hinders the affinity of the wood material with the active groups, so that it can be easily permeated into the wood material. Since no raw material is generated, the conventional solvent removal step and washing step are unnecessary, and the productivity is greatly improved.

Also, when the above epoxidized higher fatty acid ester reacts with the wood component, it becomes as if a lubricant entered between the wood components, the deformation stress of the wood material is reduced, and toughness is imparted without using a plasticizer and cracks occur. Less likely to occur.

In addition, since the polymer compound of the epoxidized higher fatty acid that is solidified and integrated in the voids of the woody material is as if the oil and fat were rubbed into the woody material, it has water repellency like an oil finish, and has no fuzz. It has a deep, wet appearance that is pressed down.

In addition, since the polymer compound reacts with the wood component in its side chain and polymerizes in the wood voids in this way, the performance can be maintained for a long time without elution with water, alcohol, etc., and the durability is also good. Is.

Furthermore, since the chemical modification, resin injection and reaction in the material as described above are completed in one operation, it is possible to greatly improve the productivity. As described above, the chemically modified modified wood of the present invention is polished. It showed a beautiful appearance only by itself, was excellent in toughness and machinability, and had a very long pot life of the impregnating liquid, which was excellent.

Claims (4)

[Claims] 1. An epoxidized higher fatty acid ester is chemically modified to an active group such as a hydroxyl group in a wood material component, and the epoxidized higher fatty acid ester and a polyvalent amine compound are polymerized and cured in the voids in the wood material. Modified wood that is characterized by being. 2. The modified wood according to claim 1, wherein the epoxidized higher fatty acid ester is epoxidized linseed oil. 3. The modified wood according to claim 1, wherein the epoxidized higher fatty acid ester is epoxidized soybean oil. 4. A polyvalent amine compound is 4.4'-diaminodiphenylmethane.
Modified wood according to item.