In order to sustain the use of wood, the need exists for a cost-effective wood protection method free from toxic preserva-tives which is capable of offering a comparable performance and durabi-lity of solvent-borne coating. Photo: IRIS
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.
DURAWOOD, a research project funded by the European Union, has set itself the
objective of developing a cost-effective, ecological, and high-performance
method: the so-called DURAWOOD process uses electrical gas discharge (plasma) to
treat wooden surfaces. The aim is to alter the surface characteristics of the
wood so that wood preservatives can adhere to it better and thus smaller amounts
of fungicide be needed.
So that wood is 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 for exterior purposes.
However, facades which have been treated with water-based preservatives are more
susceptible to discolouring and damage from mould, blue-stain fungi, and other
wood-decay fungi. The aim is for a pre-treatment of the wood by means of plasma
technology to improve the effectiveness of this water-soluble wood preservative.
Plasma technology seals the wood surface
The plasma technology is based on applying the principle of electrical gas
discharge where a so-called plasma is temporarily produced. The plasma is a gas
or gas mix which has been partly or fully ionised and thus contains free charge
carriers such as ions, charged molecules or electrons. The plasma is produced
with the aid of a DCSBD (Diffuse Coplanar Surface Barrier Discharge) electrode
of the newest generation. The wood is transported past the electrode and treated
section by section with plasma. The aim of the plasma treatment is to change the
characteristics of the wood surface, whereby two applications are used: On the
one hand, the adhesion of coatings subsequently applied, such as water-based
wood preservatives, is improved by means of a hydrophilisation of the wood
surface, and on the other hand the wettability of the wood can be reduced by a
marginal variation in the plasma parameters, as a result of which hydrophobic
surfaces are produced which increase the water resistance of the wood.
Genetic detection method for mould
The DURAWOOD technology aims to facilitate a cost-efficient, durable, and
environmentally friendly wood preservative and to strengthen the competitiveness
of the European wood-processing industry. To test the efficiency of this new
approach, the Molecular Genetics Department at ttz Bremerhaven is developing a
rapid detection method for wood-decay fungi, with which the woods treated with
the DURAWOOD process are being tested for their effective protection against
fungi. For this purpose, pure cultures of the fungus being studied were
incubated together with the wood either treated with DURAWOOD or untreated. The
next step investigates how far the fungus has grown into the wood, using the
highly sensitive PCR method, which is able to detect even only a few fungus
cells.
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.
ttz Bremerhaven regards itself as an innovative provider of research services
and operates in the field of application-oriented research and development.
Under the umbrella of ttz Bremerhaven, an international team of experts is
working in the areas of food, environment, health and consulting services.
Further Information:
ttz Bremerhaven
Fischkai 1
27572 Bremerhaven • Germany
Tel.: +49 (0)471 48 32 - 124
Fax: +49 (0)471 48 32 - 129
eMail: info@ttz-bremerhaven.de
web:
www.ttz-bremerhaven.de/en.html
german version