The present invention relates to an improved method for impregnating a porous material, such as wood, more specifically a method in which an active ingredient to be deposited within the porous material is dissolved in condensed carbon dioxide and impregnated in the material.

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 system that applies liquid conditioning agent to at least one of a plurality of sides of an untreated board is provided. One embodiment has an enclosure with a first side having a first aperture and an opposing second side with a second aperture having dimensions that correspond to the width and thickness of the untreated board; a spray applicator system comprising a plurality of spray nozzles located within a chamber and oriented inward, wherein the liquid conditioning agent is sprayed through the spray nozzles onto at least one of the sides of the untreated board as the untreated board passes through the chamber of the enclosure; a plurality of brushes located after the spray applicator system, wherein the liquid conditioning agent is brushed onto the sides of the untreated board, wherein the untreated board enters through the first aperture, and wherein a treated board exits through the second aperture.

The present disclosure describes a treated cellulosic material comprising a cellulosic material having a porous structure defining a plurality of pores, at least a portion of the pores containing a treating agent comprising a polymer, the polymer comprising a polyurethane polymer. The present disclosure further describes a method for preparing a treated cellulosic material comprising providing a cellulosic material; and a first treatment protocol comprising impregnating the cellulosic material with an aqueous dispersion comprising a polymer, the polymer comprising a polyurethane polymer; and a second treatment protocol comprising impregnating the cellulosic material with a modifying agent, the modifying agent comprising a hydrophobic amine.

The invention relates to a method for the treatment of cellulosic material. The method is comprising the steps of impregnation of the cellulosic material and treatment of the impregnated cellulosic material by a fumigation step or an evaporation step. Impregnation is performed with a metal ion M and at least one ion precursor Z yielding an impregnated cellulosic material. The at least one ion precursor Z provides an anion A or an anion A and a cation Y comprised within at least one metal salt solution I or with a metal salt solution II comprising a metal ion M. The fumigation or evaporation step is yielding a cellulosic composite material comprising a compound M(NH4)A, MYA or M(OH)x, wherein M is a metal.

A method of producing a modified wood product is disclosed. The method comprises heating a resin impregnated wood product in a reactor, the resin impregnated wood product comprising source wood impregnated with a resin composition comprising resin, the heating being so as to substantially cure the resin, thereby to produce the modified wood product. The method comprises, during the heating of the resin impregnated wood product in the reactor, introducing water into the reactor. A reactor and a modified wood product are also disclosed.

A method for improving the hydrophobic properties of a cellulosic material having a measurable moisture content without leaving an acidic residue comprises immersing the material in an inert gas, treating the material at a first temperature of between about 180° F. and about 250° F. with a vapor of silane until the silane reacts with the moisture to form hydroxysilanes and an acid vapor, then treating the material at a second temperature of between about 280° F. and about 350° F. until the hydroxysilanes convert to dehydrated silanes that are diffusely resident in the material, and removing the moisture, the acid vapor and remaining silane vapor until the treated material is substantially acid free.

An object of the present invention is to provide a flame-retardant woody material having low hygroscopicity and excellent flame-retardant performance, and a flame retardant for woody materials therefor. The present invention relates to a flame retardant for woody materials comprising an organic phosphorus compound represented by the following formula (1) and a nitrogen compound represented by the following formula (2); and also relates to a flame-retardant woody material comprising a woody material fireproofed with the flame retardant for woody materials:

##STR00001## wherein in the formula (1), R.sub.1 and R.sub.2 are the same or different, and each represents a hydrogen atom, hydroxy, or the like; n is an integer of 1 to 4; X.sub.1 and X.sub.2 are the same or different, and each represents a hydrogen atom, hydroxy, or the like; and

##STR00002## wherein in the formula (2), R.sub.3, R.sub.4, R.sub.5, R.sub.6, and R.sub.7 are the same or different, and each represents a hydrogen atom, methyl, or the like.

Disclosed is a process for the acetylation of wood. The wood to be acetylated is first subjected to an extraction step. The resulting extracted wood particularly has a reduced hemicellulose content. This extracted wood is subjected to contact with an acetylation agent. The extraction can be done with an extraction fluid which is, e.g., water, acetone, ethanol, methanol, or acetic acid. The water can be pure water, such as tap water or demineralised water, or it can be a dilute salt solutions (e.g. water containing ammonium oxalate or sodium sulphite). Hot water extraction is preferred. The resulting acetylated extracted wood, particularly wood elements, have a desirable swelling behaviour at lower acetyl contents than conventional acetylated wood. The wood can be in the form of wood elements, solid wood, or wood veneers.

Highly transparent (up to 92% light transmittance) wood composites have been developed. The process of fabricating the transparent wood composites includes lignin removal followed by index-matching polymer infiltration resulted in fabrication of the transparent wood composites with preserved naturally aligned nanoscale fibers. The thickness of the transparent wood composite can be tailored by controlling the thickness of the initial wood substrate. The optical transmittance can be tailored by selecting infiltrating polymers with different refractive indices. The transparent wood composites have a range of applications in biodegradable electronics, optoelectronics, as well as structural and energy efficient building materials. By coating the transparent wood composite layer on the surface of GaAs thin film solar cell, an 18% enhancement in the overall energy conversion efficiency has been attained.