JPH06226710A - Manufacture of modified wood - Google Patents

Abstract

PURPOSE:To obtain the dimensional stability and high durability of wood-based material (hereinafter referred to as wood). CONSTITUTION:The modified wood concerned is produced by clampingly laminating wood or wood-based material in multiply, which is obtained by impregnating, immersing or coating chemical agent mainly composed of cyclic ester compound as beta-propiolactone, delta-valerolactone, epsilon-caprolactone and the like and the initial condensate of formaldehyde-based resin such as melamine resin, urea resin, glyoxalic resin, phenolic resin and the like, to wood or wood-based material.

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 to be treated or the wood material to be treated obtained by coating is laminated in multiple layers and subjected to pressure lamination treatment to modify the wood.

Further, the wood is a rotary veneer or slice veneer having a thickness of 0.3 to 5 mm, and the compression laminating process is
This is a heat compression lamination process.

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.

The veneer used in the present invention may be a lumber product obtained by a band saw or the like, a sawn plate, a wood fiber board or a chip board, but a rotary veneer having a thickness of 0.3 to 5 mm or a slice veneer can be used. By using it, cheaper and easier processing becomes possible. Generally, in rotary veneer and slice veneer with a size of 1 mm or more, cracks that occur during processing accompany the wood surface, which promotes the penetration of chemicals, and the chemicals can be applied to the interior of the wood without the need for operations such as depressurization. Infiltrate.

The modified wood according to the present invention is obtained by impregnating, dipping or applying the chemical with respect to 100 of the weight of the wood so that the amount of adhesion is 10 to 300, and then stacking in multiple layers and pressing and laminating. Obtained by At this time, it is desirable to heat-treat the wood and the chemicals or the chemicals in order to react with each other. It is desirable to increase the chemical concentration, to increase the density of the wood, and to prevent damage to the wood structure. It is desirable to compress so that the thickness after pressure-lamination does not become 50% or less of the original thickness.

As means for laminating under pressure, a cold press,
A roll press, a double belt press, etc. may be mentioned. Further, as means for heating and compression or heat compression lamination, heating means such as steam, electricity, high frequency or microwave, and the above-mentioned means capable of compression or compression are used. Examples thereof include a hot press, a roll press, and a double belt press provided, but are not particularly limited thereto.

The conditions for pressure laminating are that the temperature is from room temperature to 200.
It is desirable that the temperature is 5 ° C., the pressure is 5 to 50 kg / cm ² , and the time is 0.1 to 72 hours. The pressure lamination conditions are appropriately selected depending on the mixing ratio of the cyclic ester compound and the formaldehyde-based initial condensate. In terms of reactivity, damage, damage to wood tissue, etc., the temperature should be 6 for more efficient treatment.
0 ~ 160 ℃, pressure 8 ~ 30Kg / cm ² , time 0.1 ~
It is preferably within a range of 3 hours.

Further, it is desirable that the treated wood be laminated so as to be orthogonal to each other in the pressure-lamination, because the dimensional stability of the obtained modified wood is further improved.

Further, an adhesive such as a melamine-urea resin adhesive, a phenol resin adhesive, a resorcinol resin adhesive, an epoxy resin adhesive, a urethane resin adhesive or the like is applied to the treated wood and pressure-laminated. Is also possible.

[0022]

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 appropriate hardness to the wood and acts as an adhesive for the wood by undergoing a condensation reaction in the wood to be crosslinked, and also forms 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 produced 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.

[0026]

【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 prepared as a solid content with respect to 100 parts by weight of ε-caprolactone. , 5 ammonium chloride as a curing catalyst
After addition of 5% by weight, a 5 mm thick cedar veneer was laminated with 5 pieces of wood to be treated, which were obtained by impregnating the cedar veneer with a reduced pressure and pressure method so that the chemical adhesion amount was 150 with respect to 100 of the veneer. It was cold pressed under the conditions of room temperature, pressure of 15 kg / cm ² , and time of 8 hours to obtain modified wood having a thickness of about 25 mm.

Example 2 A mixture of 100 parts by weight of methyletherified melamine resin initial condensation product (trade name; UM-2, manufactured by Aika Kogyo Co., Ltd.) with 100 parts by weight of ε-caprolactone as a solid content of water-methyl alcohol. To a drug adjusted to 30% by weight with a mixed solvent (1: 1 by weight), hydrochloric acid is added as a curing catalyst to 2%.
After adding 5% by weight, 5 mm-thick cedar veneer was impregnated by the pressure reduction method so that the chemical adhesion amount was 100 with respect to 100 veneer weight, and then air-dried to obtain 5 to-be-treated wood.
After stacking the sheets, the temperature is 120 ° C, the pressure is 15 Kg / cm ² , and the time is 30.
Hot-pressing was performed under the condition of minutes to obtain a modified wood having a thickness of 24 mm.

Example 3 A cedar rotary veneer having a thickness of 2.8 mm was dipped with the chemical agent used in Example 1 at room temperature and atmospheric pressure, and treated wood having a chemical adhesion amount of 100 per 100 weight of the veneer was treated. Obtained. Nine sheets were laminated and hot pressed under the conditions of a temperature of 80 ° C., a pressure of 10 kg / cm ² , and a time of 30 minutes to obtain a modified wood having a thickness of 24.5 mm.

Example 4 A cedar rotary veneer having a thickness of 2.8 mm was immersed in the chemical agent used in Example 2 at room temperature and atmospheric pressure and then air-dried. The treated wood was obtained. 10 pieces of this are laminated and the temperature is 120 ° C. and the pressure is 25 kg / cm ² ,
Hot-pressing was performed for 30 minutes to obtain a modified wood having a thickness of 25 mm.

Example 5 A mixture of 150 parts by weight of a methyletherified melamine resin initial condensation product (trade name; UM-2, manufactured by Aika Kogyo Co., Ltd.) with 100 parts by weight of ε-caprolactone as a solid content of water-methyl alcohol. To a drug adjusted to 30% by weight with a mixed solvent (1: 1 by weight), hydrochloric acid is added as a curing catalyst to 2%.
The chemicals added by weight% are immersed in a 2.8 mm thick cedar rotary veneer at room temperature and atmospheric pressure, and then air-dried to give a veneer weight of 100.
A treated wood having a chemical adhesion amount of 80 was obtained. Ten pieces of this were laminated and heat-pressed under the conditions of a temperature of 120 ° C., a pressure of 25 kg / cm ² , and a time of 30 minutes to obtain a modified wood having a thickness of 25 mm.

Example 6 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 with 40 parts by weight of methyl alcohol. % Of the chemical agent was dipped in a 2.2 mm thick cedar rotary veneer at room temperature and atmospheric pressure for 4 hours, then at 40 ° C-2
After drying for a period of time, a treated wood having a chemical adhesion amount of 110 with respect to 100 of veneer was obtained. Twelve of these were laminated and heat-pressed under the conditions of a temperature of 140 ° C., a pressure of 15 kg / cm ² , and a time of 20 minutes to obtain a modified wood having a thickness of 25 mm.

Example 7 A cedar rotary veneer having a thickness of 2.2 mm was coated with the drug used in Example 6 by a roll spreader and dried at 40 ° C. for 2 hours to adhere the drug to 100 veneers. An amount of treated wood of 50 was obtained. Further, a phenol resin adhesive (trade name; P-75, manufactured by Aika Kogyo Co., Ltd.) was applied to the treated wood at a coating amount of 200 g / m ² , 12 sheets were laminated, and the temperature was changed in the same manner as in Example 6. Hot-pressing was performed under the conditions of 140 ° C., a pressure of 15 kg / cm ² , and a time of 20 minutes to obtain a modified wood having a thickness of 25 mm.

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 (1: 1 by weight ratio), and a chemical agent to which 0.2% by weight of phosphoric acid was added as a curing catalyst was 5 mm.
Sugi veneer was impregnated by vacuum impregnation method, then air dried,
A treated wood having a chemical adhesion amount of 120 with respect to a veneer weight of 100 was obtained. 5 sheets are laminated and heat pressed under the conditions of temperature 120 ° C, pressure 15Kg / cm ² , time 30 minutes, thickness 24mm
Obtained treated wood.

Comparative Example 2 The chemical used in Comparative Example 1 was immersed in a 5 mm cedar veneer at room temperature and atmospheric pressure, and then air-dried to give a treated wood having a chemical adhesion amount of 80 with respect to 100 veneer weight. Got Five pieces of this were laminated and heat-pressed under the conditions of a temperature of 120 ° C., a pressure of 15 kg / cm ² and a time of 30 minutes to obtain a treated wood having a thickness of 24 mm.

Comparative Example 3 ε-caprolactone was adjusted to 30% by weight with water, and 0.1% by weight of phosphoric acid was added as a curing catalyst to a 2.8 mm thick cedar rotary veneer at room temperature. After soaking under pressure for 5 hours, it was air-dried to obtain a treated wood having a chemical adhesion amount of 120 per 100 weight of veneer. Nine sheets were laminated and hot pressed under the conditions of a temperature of 80 ° C., a pressure of 10 kg / cm ² , and a time of 30 minutes, but they were peeled off after decompression.

Comparative Example 4 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 to a cedar veneer having a thickness of 25 mm at room temperature and atmospheric pressure was used. After soaking for a period of time, it was air-dried to obtain treated wood having a chemical adhesion amount of 50 with respect to 100 of veneer. The temperature is 120 ℃, the pressure is 15Kg / cm ² ,
Heat treatment was carried out under the condition of 30 minutes to obtain a 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 a mirror plate having a curved surface shape, and a normal urethane resin coating was applied to the surface, which was exposed outdoors at a 45 ° south surface for half a year, and the change in appearance was observed.

The results are shown in Table 1.

[Table 1]

[0040]

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.

By using an inexpensive rotary veneer or other material having fine cracks as a raw material, it is not necessary to use a special means such as a depressurization method, and the processing cost can be reduced.

Further, in the case of laminating compaction, heating compaction or compression leads to shortening of compaction time, which not only enhances productivity but also enhances concentration and density of chemicals and wood, but also causes reaction. It also has the effect of promoting it.

Claims (3)

[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,
It is possible to press-laminate multiple layers of treated wood or treated wood material obtained by impregnating, dipping or applying a chemical containing the initial condensate of formaldehyde resin such as glyoxal resin and phenol resin. A characteristic method for producing modified wood. 2. The wood or wood material has a thickness of 0.3.
The method for producing modified wood according to claim 1, which is a rotary veneer or slice veneer having a thickness of 5 mm. 3. The method for producing a modified wood according to claim 1, wherein the compression-lamination treatment is a heat-compression lamination treatment.