The fact that wood acquires the property of enhanced endurance under heating has been known to mankind for millennia. Modern thermo treatment is carried out by means of gradual heating of wood up to the temperatures of 410-450° F in special heat chambers made of stainless steel, under anoxic conditions. The anoxic conditions are required due to the fact that wood combustion takes place at a temperature of over 300° F, and the desired reactions within the wood starts at temperatures of over 380-400° F. There are different modes of wood treatment: by heating in oil, in nitrogen, and in water vapour, with the last-noted being the most effective. The thermo-treatment cycle includes preliminary drying under water-saturated conditions to reach residual stress relief, heating up to the temperatures of wood treatment, exposure to the given temperatures, cooling with condensation, and moisture saturation of the treated wood. Steam is used to prevent the wood from burning or cracking, and creates the chemical changes which result in a durable, weather resistant and stable wood product. The changes in the wood become irreversible and afford a lifetime.
Thermo-Treated Wood is a new generation of wood material. It combines such unique properties as water repellency, weather resistance and dimensional stability. A beautiful brown tint and natural wooden grain along with these new properties, make this material an ecologically friendly alternative to chemically treated wood.
Several thermo treating technologies were first used in the mid 1990's in Finland and France. Presently, thermo treatment technology is conquering the world. Since 2005 in USA and Canada no chemical wood protection additives are allowed in such sectors as children’s playground production, decks for waterfront homes, etc. In the European Union, chemical additives usage in wood protection were prohibited in 2004. The thermo-treatment market grows in Europe by 30% a year.
Thermo-treatment significantly improve various characteristics of wood and protects wood by using heat and steam without any chemical additives. The molecular changes in wood composition have a result of dimensional stabilization, protection against rot and wither, and as a result, expands usage opportunities.
THREE MAJOUR PROPERTIES OF THERMO-TREATED WOOD:
- Resistance to biological decay:
Thermo-Treated Wood has durability and resistance to biological decay 15-25 times higher than untreated wood. Under high temperature treatment, polysaccharides found in natural wood decompose, while the residual humidity (4-6%) and release of connected on molecular level water eliminates the conditions for the origination fungus and microorganisms.
- Water-repelling at a molecular level: Thermo-Treatmed Wood retains 3 to 5 times less moisture at a molecular level than untreated wood.
- Dimension stability: Thermo-Treated Wood maintains very high (up to 5-15 times in comparison with untreated wood) dimension stability under extreme changes of both humidity and temperature.
The molecular structure of the thermo-treated wood is comparable with a 350-year old wood.
Thermo-Treated Wood is now widely used for all kinds of interior and outdoor projects such as exterior siding, decks, furniture production (especially for gardens), musical instruments, flooring, parquet, windows, doors, fences and highway acoustical barriers. Other products in which thermo-treated wood is ideal are those applications in high moisture environments such as boardwalks, swimming pool areas, trim of yachts, landscape design, manufacturing of bathtubs, wash-bowls, floors and facing tile of bathrooms, and many other applications.
ADVANTAGES OF THERMO-TREATED WOOD PRODUCTS:
- Surface improved quality repels dust
- Much longer life and improved decay resistance
- Greatly improved durability
- In most cases does not require painting
- Significant wither reduction
- Extended stability to pressure
- Uniformity of color at all depths
- Stability in high temperatures
- Increased fire-protection and heat-resistant properties
- Retains the aroma of a natural tree
- Supreme ecological purity