Development of a new solvent-free coating method for wooden facades
Research for the benefit of SME – 7th Framework Programme
01.12.2009 – 30.11.2011
Anne Baars , Dr. Ingo Klarholz
In order to raise the competitiveness of wood compared to other materials, it is necessary to develop a cost-efficient method of wood protection which is free of toxic chemicals and nevertheless guarantees the wood’s long durability.
The objective of the DURAWOOD project is therefore to develop a cost-efficient, ecological, and high-performance method. This is referred to as the DURAWOOD process and uses electrical gas discharge (plasma) to treat or pre-treat wooden surfaces so that smaller amounts of fungicide need be used.
So that wood can compete with other materials and be attractive for customers, it must be possible to guarantee the durability of treated wooden facades for at least 5 to 8 years and without the need for any additional maintenance. New EU legislation (2004/42/EC) demands the replacement of solvent-based wood preservatives by water-based alternatives for exterior purposes. However, wood facades which have been treated with water-based preservatives are more susceptible to discolouring and damage from mould, blue-stain fungi, and wood-decay fungi.
Mould mostly grows on the surface of the paint layer and the damage for which it is responsible results from discolouring caused by pigmented spores. Blue-stain fungi can colonise both the surface as well as the whole wood body and lead to often unsightly discolouring (blue or grey) as well as impairing the wood’s protection by damaging the surface coating. Wood-decay fungi are able to break down lignin or cellulose and thus lead to massive structural damage of the wood, which makes complex and expensive repair measures necessary. That is why researchers from the Molecular Genetics Department at ttz Bremerhaven are relying on a method based on plasma technology.
Two applications are being used. On the one hand, the wood surface is hydrophobised in order to reduce the wettability of the wood and thus make it impermeable to water. On the other hand, the wood surface is altered in such a way that the adhesion of water-based preservatives is improved.
The DURAWOOD technology aims to provide a cost-efficient, durable, and environmentally friendly wood preservative and to strengthen the competitiveness of the European wood-processing industry.
The Molecular Genetics Department at ttz Bremerhaven is developing a rapid detection method for the most important types of wood-decay fungi, with which the woods treated with DURAWOOD are being tested for their effective protection against fungi.
ttz Bremerhaven is one of three research partners. Together with IRIS (Innovacio i Recerca Industrial i Sostenible, Barcelona), the Project Coordinator, and the Slovak University of Technology in Bratislava, ttz is a research service provider in the consortium. The consortium’s industrial partners are composed on the one hand of the following wood-processing firms: Ing. Ján Šestina – SETA from Slovakia, Kartas Kontrplak Sanayi Ticaret from Turkey, and Aryecla, S.L. from Spain, and on the other hand of the following companies in the supply chain of the targeted technology: Plasma Technologic s.r.o. from the Czech Republic, which is specialised in plasma technology; PAM-ak s.r.o. from Slovakia and SETAS KIMYA SAN AS from Turkey are both manufacturers of wood coatings.