Provided is a wooden sheet having high flexibility (for example, folding resistance) and processability (for example, degree of processing freedom) even if the wooden sheet is considerably thick. Also provided is a method that can be used to produce such a wooden sheet. The wooden sheet is modified with a modifying agent including a combination of an acid or an alkali and a compound having a hydroxyl group.

Provided is a wooden sheet having high flexibility (for example, folding resistance) and processability (for example, degree of processing freedom) even if the wooden sheet is considerably thick. Also provided is a method that can be used to produce such a wooden sheet. The wooden sheet is modified with a modifying agent including a combination of an acid or an alkali and a compound having a hydroxyl group.

A method for preparing a wood preservative composition, includes modifying lignin with Na.sub.2B.sub.4O.sub.7 or NaNO.sub.3 and then with a chromium (II) salt, copper (II), cadmium (II) or zinc (II), for example, metal nitrates (Cr(NO.sub.3).sub.2, Cu(NO.sub.3).sub.2, Cd(NO.sub.3).sub.2, Zn(NO.sub.3).sub.2); to the preservative obtainable by this method; and to a method for preserving wood; and to the preserved wood. The preservative prevents degradation by xylophagous and fungal agents, and also improves some properties of the wood, and the hygroscopicity and fire resistance.

A method for preparing a wood preservative composition, includes modifying lignin with Na.sub.2B.sub.4O.sub.7 or NaNO.sub.3 and then with a chromium (II) salt, copper (II), cadmium (II) or zinc (II), for example, metal nitrates (Cr(NO.sub.3).sub.2, Cu(NO.sub.3).sub.2, Cd(NO.sub.3).sub.2, Zn(NO.sub.3).sub.2); to the preservative obtainable by this method; and to a method for preserving wood; and to the preserved wood. The preservative prevents degradation by xylophagous and fungal agents, and also improves some properties of the wood, and the hygroscopicity and fire resistance.

Disclosed herein are compositions and methods for treating wood to give it a desirable color that is durable over time, while at the same time rendering the wood resistant to fungal decay and insect attack. The wood may be pressure treated in a two-step process whereby the wood is first treated with a wood preservation composition, and then treated with a composition comprising pigments, or vice versa. Alternatively, the wood may be simultaneously treated with a composition comprising a wood preservative and a composition comprising pigments.

Disclosed herein are compositions and methods for treating wood to give it a desirable color that is durable over time, while at the same time rendering the wood resistant to fungal decay and insect attack. The wood may be pressure treated in a two-step process whereby the wood is first treated with a wood preservation composition, and then treated with a composition comprising pigments, or vice versa. Alternatively, the wood may be simultaneously treated with a composition comprising a wood preservative and a composition comprising pigments.

A filler material is applied to a plurality of wood elements. The plurality of wood elements is bonded into a composite wood product, where the bonding includes delivering ultrasound energy to the plurality of wood elements. The ultrasound energy has a frequency within a frequency range of 10 kHz-20 MHz.

The present description relates to processes, water-based wood treatment solutions and kits for treating wood substrates so as to obtain colored (or altered) wood substrates, where mineral compounds that impart the color or other desirable characteristic(s) to the wood substrates are formed in the colored or altered wood substrates. The mineral compounds formed comprise the products of a chemical reaction which occurs between the wood substrate, a metal salt, and an oxygen source.

A method for reinforcing and enhancing bamboo/wood materials employs a sulfuric acid hydrolysis method to prepare a nanocellulose dispersion solution; then with the nanocellulose dispersion solution having a certain concentration as a precursor, nano zinc oxide is in-situ produced on the surface of the nanocellulose; and the cellulose dispersion solution is improved by compounding. The obtained treatment solution is impregnated into the pores of bamboo/wood materials in a specific manner to play the role of filling, binding and consolidating the bamboo/wood tissues, so that the treated bamboo/wood materials have enhanced hardness, strength and dimension stability, and significantly-improved mildew- and corrosion-resistance. The method is suitable for the reinforcing and enhancing treatment of wood materials with relatively-loose texture, such as fast-growing wood and wood from a planted forest, and is also suitable for the reinforcement and restoration of slightly-rotten wood materials.

Provided is a multi-layered reinforced wood material which is excellent in fire resistance, has extremely small damages on a support wood material part, and is also excellent in strength. The present invention is directed to a multi-layered reinforced wood material A for use as a building material, the multi-layered reinforced wood material A including a support wood material part 1 for supporting load, a sheet part 3 attached to the periphery of the support wood material part 1, an inflammable wood material part 2 attached outside the sheet part 3 so as not to expose the sheet part 3, wherein the inflammable wood material part 1 is made of a wood material containing therein an inflammable agent, and the sheet part 3 is made of a fiber reinforced plastic.