– Interesting applications for the material is, for example, floors and ceilings, where good water resistance and temperature resistance is sought after. It is also suitable as outdoor facade because the material resists mold growth and UV light in a good way, says Carmen Cristescu, researcher in Wood Science and Engineering at Luleå University of Technology in Skellefteå, who developed the product.
Pressure and heat
The new wood material is generated by self-bonding of veneers in which a number of untreated wood veneers are bonded under high pressure and high temperature, about 250°C. The environmentally friendly process takes place without glue or other chemical additives and the result is a compressed brown wooden board with improved properties which is ideal as building material.
– In the manufacture of construction parts, the process can be particularly interesting because the density of the material can be predetermined before pressing, and optimized according to design requirements, says Carmen Cristescu.
Other advantages with the material is that it is fire resistant, dimensionally stable and insulating. By combining the parameters of temperature, pressure and pressing time, Carmen Cristescu has been able to optimize the material properties. By observing the color change on the edges of the veeners, she could also predict the material's hardness. Carmen Cristescu has mainly used the wood species beech, but has also begun to test the method on pine, spruce, birch and aspen.
Challenges with commercialization
Some work remains before an eventual commercialization of the new material, which has good potential to succeed on the world market.
– The main issue is to control the thickness and color of the boards. Wood is a complex natural material and the self-bonding process, where the material is partially decomposed, is not easy to control because of this. To be accepted by the market, well-tested and documented material properties are required, before it can be introduced for customers and producers, says Carmen Cristescu.
The new wood product is presenteded in Carmen Cristescu's dissertation: Influence of Pressing parameters on mechanical and physical properties of the self-bonded laminated beech boards.