JPH06238613A - Manufacture of reformed timber - Google Patents

Abstract

PURPOSE:To stabilize dimension of a wood material and improve durability of the wood material. CONSTITUTION:A timber or a wood material is impregnated with, dipped in or coated with a drug containing as main components a cyclic ester compound such as B-propiolactone, delta-valerolactone, epsilon-caprolactone, and an initial condensation product of formaldehyde resin such as melamine resin, urea resin, glyoxal resin, phenol resin. Then, the drug is reacted and cured in the timber or the wood material. Further, as a processing for reacting and curing, heat compression processing is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to dimensional stabilization and high durability of wood or wood materials (hereinafter referred to as wood).

[0002]

2. Description of the Related Art The applicant of the present invention has filed Japanese Patent Application No. 4-171620.
JP-A-4-135701 discloses a method for producing modified wood in which wood is treated with a chemical agent containing a cyclic ester compound such as ε-caprolactone as a main component, and according to JP-A-4-135701, wood subjected to steam heating is treated with etherified melamine. A method for producing a dimensional stability-improved wood treated with a thermosetting resin such as a resin has been disclosed.

[Problems to be Solved by the Invention]

However, the wood modified with a cyclic ester compound has drawbacks such as softening and lowering of surface hardness and easy scratching. On the other hand, it is treated with formaldehyde resin such as melamine resin. The timber is
Although the surface hardness is high, cracking is likely to occur due to cracking during heat treatment and changes in stress generated during the treatment process over time, and because the molecular weight of the chemical is large, it is necessary to treat the interior of the wood under reduced pressure and pressure. However, there are drawbacks such as being difficult to process.

As a means for solving the above problems of the prior art, a water-soluble and oil-soluble cyclic ester compound and a water-soluble or oil-soluble compound, a formaldehyde-based initial condensate, are added in appropriate proportions. It was found that by compounding with, the polymerization in wood occurs simultaneously with the esterification and etherification of wood.

The cyclic ester compound causes a ring-opening reaction as shown by the formula 1 and a polymerization reaction under an appropriate catalyst to produce a polyester.

[Formula 1]

Further, the formaldehyde-based precondensate is
Since it has a methylol group at the terminal, it reacts with the monomer or polymer of the cyclic ester compound as shown in Formula 2 to produce an esterification or etherification reaction product.

[Formula 2]

In the present invention, these reactions are carried out in wood to modify the wood. When the above reaction is carried out in wood, it also reacts with hydroxyl groups in wood, It causes esterification and etherification to chemically modify wood.

The wood modified by such a reaction not only has improved dimensional stability, but also has the respective advantages of wood treated with a cyclic ester compound alone or an etherified melamine resin alone. .

[Means for Solving the Problems]

The present invention is applicable to wood or woody materials with β-
Impregnation and immersion of a chemical agent containing a cyclic ester compound such as propiolactone, δ-valerolactone, and ε-caprolactone, and an initial condensation product of formaldehyde resin such as melamine resin, urea resin, glyoxal resin, and phenol resin as main components Alternatively, the wood is modified by applying it and then subjecting the chemical to the reaction curing in the wood or the woody material and treating.

Further, the reaction curing treatment is a heat compression treatment.

The cyclic ester compound used in the present invention includes β-propiolactone, δ-valerolactone, ε-
Examples thereof include compounds such as caprolactone, coumarin, tetronic acid, pyrone, and phthalide, or derivatives thereof. More preferred is β-, which is cost-effective and highly reactive.
It is desirable to use propiolactone or ε-caprolactone.

The above cyclic ester compound reacts sufficiently without using a catalyst, but it is also possible to add a small amount of the catalyst in order to carry out the reaction efficiently. Examples of the catalyst include alkali metal or alkali metal hydrides, hydroxides, carbonates, acetates, alkyl metals, anionic polymerization catalysts such as aliphatic amines, and cationic polymerization catalysts or metals such as inorganic acids and metal halides. Coordination anion-based polymerization catalysts such as a compound of alkyl and alkyl, a halogenated alkyl metal, and a metal alkoxide can be used, and are appropriately selected by blending with a formaldehyde-based initial condensate described below.

Examples of the formaldehyde-based initial condensate compounded with the cyclic ester compound include melamine resin, urea resin, dicyandiamide resin, glyoxal resin, phenol resin, resorcinol resin, and derivatives and cocondensates thereof. Without coloring,
Moreover, melamine resin, urea resin, which also serves as an adhesive for wood,
Glyoxal resins and their derivatives or their co-condensates are preferred.

In the present invention, the cyclic ester compound and the formaldehyde initial condensate are used in a weight ratio of 1 to 100: 1.
Wood is treated with a chemical agent blended at a ratio of 0 to 1, but the blending ratio is appropriately selected depending on the purpose of use of the treated wood, for example, a wooden entrance which does not require high surface hardness and is harsh in environmental conditions. For doors and the like, the mixing ratio is preferably about 1 to 10: 1 by weight, and for frame materials etc. that are apt to be scratched and require high strength to support the door. , 1: 1 by weight ratio
It is preferably about 10 to 10.

Furthermore, in order to control the amount of adhesion to wood from the viewpoint of cost, it is possible to add various solvents compatible with the above-mentioned chemical agents and dilute them. In this case, as a solvent Is preferred to have lower reactivity with a drug, and specific examples include hexane, aliphatic hydrocarbons such as heptane, aromatic hydrocarbons such as toluene and xylene, diethyl ether, diisopropyl ether, tetrahydrofuran, ethers such as dioxane, and acetic acid. Examples thereof include esters such as ethyl and butyl acetate, ketones such as acetone and methyl ethyl ketone, and solvents such as water and alcohols can be used, but are not limited thereto.

As the wood used in the present invention, lumber products obtained by band saws, sawn timbers, wood fiberboards, chipboards and the like can be used.

The modified wood according to the present invention is obtained by impregnating, immersing or applying the chemical so that the amount of adhesion becomes 10 to 300 with respect to 100 weight of the wood, and then curing the reaction at room temperature or under heating. Obtained by

Means for reacting and curing the chemical agent include standing at room temperature or pressing, steam, electricity, high frequency,
Examples include means such as stationary or pressing in a furnace or a press equipped with a heating device using microwaves,
It is desirable to heat-press to react wood and chemicals or chemicals to each other. It is possible to further increase the concentration of chemicals, to make the surface of wood uniform and densified, and to prevent damage to wood tissue. It is desirable to heat and compress so that the thickness of the modified wood does not become 50% or less of the original thickness.

Clamping conditions are as follows: temperature: room temperature to 200 ° C.,
The pressure is preferably 5 to 50 Kg / cm ² , and the time is preferably 0.1 to 72 hours, but these compression conditions are appropriately selected depending on the mixing ratio of the cyclic ester compound and the formaldehyde-based initial condensate, and the reactivity is In order to treat the wood tissue more efficiently from the standpoint of damage to the wood tissue, the temperature is 60-
160 ° C., pressure: 8-30 Kg / cm ² , time: 0.1
It is preferably within a range of 3 hours.

[0020]

The mechanism of dimensional stabilization of wood in the present invention is to introduce a cyclic ester compound having a high affinity for wood and a preform condensate of formaldehyde resin into the wood so that the cyclic ester compound inside the wood can be used as a catalyst or under heating. Not only undergoes an etherification reaction or an esterification reaction with the wood or formaldehyde resin initial condensate, but also facilitates the polymerization reaction of the cyclic ester compound itself and the graft reaction with the wood or formaldehyde resin initial condensate. Done.

Further, the formaldehyde-based resin initial condensate not only not only imparts an appropriate hardness to the wood and acts as an adhesive agent for the wood by undergoing a condensation reaction in the wood to be crosslinked, and also a monomer or a cyclic ester compound. By reacting with the polymer as described above, giving flexibility to the formaldehyde resin, as a result, following the minute dimensional change of the wood due to stress and humidity change caused by heat treatment,
The generation of new cracks, which is a drawback of wood, is suppressed, and the modified wood is stabilized.

The etherification product or esterification product formed by such a reaction, and the polyester or formaldehyde resin cross-linked product or graft polymer are chemically stable and can sufficiently withstand leaching with water or alcohol.

Further, by heating and compressing, not only the above reaction is promoted, but also the chemical concentration and the wood density are increased, and the obtained modified wood is further stabilized.

[0024]

【Example】

Example 1 A mixture of 200 parts by weight of a urea resin initial condensate (trade name; UN-811, manufactured by Aika Kogyo Co., Ltd.) with 40 parts by weight of water was adjusted to 100 parts by weight of ε-caprolactone as a solid content. After adding 5% by weight of ammonium chloride as a curing catalyst to the above chemicals, a cedar veneer with a thickness of 25 mm was
A modified wood was obtained by impregnating the veneer with a depressurizing method so that the amount of the chemical adhered was 80 with respect to the weight of the veneer, and allowed to stand at room temperature.

Example 2 A mixture of 100 parts by weight of ε-caprolactone as a solid content and 100 parts by weight of a methyletherified melamine resin initial condensation product (trade name; UM-2, manufactured by Aika Kogyo Co., Ltd.) was added to water. 30% by weight in a mixed solvent of methyl alcohol
After adding 2% by weight of hydrochloric acid as a curing catalyst to the drug prepared as described above, the pressure was applied to a 25 mm-thick cedar veneer so that the amount of the drug adhering to 100 veneer of the veneer was 60 parts by weight. Impregnate and then dry at 60 ° C for 1 hour at temperature 1
Hot-pressing was carried out under the conditions of 20 ° C., pressure of 15 Kg / cm ² , and time of 30 minutes to obtain modified wood having a thickness of 24 mm.

Example 3 The chemical agent used in Example 1 was immersed in a 25 mm thick veneer at room temperature under normal pressure, and the adhesion amount of the agent was 3 with respect to 100 weight of the veneer.
0 treated wood was obtained. This is temperature 80 ℃, pressure 15K
g / cm ² , hot pressed under the condition of 30 minutes, thickness 24 mm
The modified wood of was obtained.

Example 4 The treated wood obtained in Example 2 was treated at a temperature of 120 ° C. and a pressure of 2
Heat-pressed under conditions of 5 Kg / cm ² and time of 30 minutes to obtain a thickness of 22
mm modified wood was obtained.

Example 5 A mixture of 100 parts by weight of β-propiolactone as a solid content and 50 parts by weight of a phenol resin initial condensation product (trade name; P-65, manufactured by Aika Kogyo Co., Ltd.) was added to methyl alcohol. The chemicals adjusted to 40% by weight were immersed in a 25 mm thick cedar rotary veneer at room temperature and atmospheric pressure, then at 40 ° C-2.
After drying for an hour, a treated wood having a chemical adhesion amount of 30 per 100 weight of veneer was obtained. This was hot pressed under conditions of a temperature of 120 ° C., a pressure of 25 kg / cm ² , and a time of 20 minutes to obtain a thickness of 2
2 mm of modified wood was obtained.

Comparative Example 1 Methyletherified melamine resin initial condensate (trade name: U
M-2, manufactured by Aika Kogyo Co., Ltd., was adjusted to 30% by weight with a water-methyl alcohol mixed solvent and used as a curing catalyst.
A 25 mm cedar veneer was impregnated with 2% by weight of phosphoric acid by a reduced pressure impregnation method, and then dried at 60 ° C. for 1 hour. Obtained treated wood. Temperature 120 ℃, Pressure 15Kg / c
Heat treatment was performed under the conditions of m ² and time of 30 minutes to obtain treated wood having a thickness of 24 mm.

Comparative Example 2 A phenol resin initial condensate (trade name: P-65, manufactured by Aika Kogyo Co., Ltd.) adjusted to 30% by weight with methyl alcohol was applied to a 25 mm cedar veneer at room temperature and atmospheric pressure. After the immersion, it was dried at 40 ° C. for 2 hours to obtain treated wood having a chemical adhesion amount of 20 with respect to a weight of 100 veneers. This was hot pressed under the conditions of a temperature of 120 ° C., a pressure of 25 kg / cm ² , and a time of 20 minutes to obtain a treated wood having a thickness of 22.5 mm.

Comparative Example 3 A chemical prepared by preparing 30% by weight of ε-caprolactone with water and adding 0.1% by weight of phosphoric acid as a curing catalyst was immersed in a cedar veneer having a thickness of 25 mm at room temperature and atmospheric pressure. Then air dry,
A treated wood having a chemical adhesion amount of 50 with respect to a veneer weight of 100 was obtained. This is temperature 120 ℃, pressure 15Kg / c
Heat treatment was performed under the conditions of m ² and time of 30 minutes to obtain treated wood having a thickness of 24 mm.

Surface hardness of modified wood of Examples and Comparative Examples,
For dimensional stability and bending strength, Brinell hardness test,
Anti-swelling Efficienc (40 ° C-30% RH, 40 ° C-90% RH)
y: ASE) and the bending test method based on JIS Z-2113.

Further, the modified wood was processed into an end plate having a curved surface shape, and a normal urethane resin coating was applied to the surface of the south surface for 45 minutes, and then exposed to the outside for half a year, and the change in appearance was observed. The results are shown in Table 1.

[0034]

[Table 1]

[0035]

Industrial Applicability The modified wood obtained by the present invention has a linear component and a crosslinked component in the wood by chemical modification with the wood and etherification or esterification reaction between the compounds constituting the drug. It becomes stable both chemically and physically because of the entanglement of wood, and the effect is not only the dimensional stabilization of the wood by the cyclic ester compound and the improvement of the physical strength by the formaldehyde resin, but also the drawbacks of wood products. The cracking and the peeling of the coating film due to the change with time are suppressed.

Further, since the cyclic ester compound to be blended with the formaldehyde-based resin initial condensate is a monomer and has a small molecular weight, it easily permeates into the wood by a simple means such as immersion at room temperature and atmospheric pressure, The wood is modified by such a reaction.

Further, when heat-pressing or compressing at the time of reaction curing, the production process is shortened, productivity is increased, and not only the concentration and density of chemicals and wood are increased but also the reaction is accelerated. There is also an effect.

Claims (2)

[Claims] 1. A wood or wood material containing cyclic ester compounds such as β-propiolactone, δ-valerolactone and ε-caprolactone, a melamine resin, a urea resin,
Characterized in that it is impregnated, dipped or coated with a chemical agent containing an initial condensation product of a formaldehyde resin such as a glyoxal resin or a phenolic resin, and then the chemical agent is reacted and cured in the wood or wood material to be treated. To make modified wood. 2. The method for producing modified wood according to claim 1, wherein the reaction curing treatment is a heat compression treatment.