

Full House in Amsterdam
A sell-out and a waiting list: Anyone interested in participating in the 10th anniversary of the Woodcoatings Congress had to be quick off the mark to register. The 190 participants who gathered together in Amsterdam on 25 and 26 October were treated to an enthralling congress.
The fact that wood is a natural raw material was well reflected in the programme. Compared to other coatings congresses, this one featured a disproportionately high number of contributions on the topic of bio-based materials. Thus, Ewelina Depczynska from the Tikkurila Group set out to establish what is meant by bio-based in the first place. She addressed such questions as: When can a product be considered bio-based? What is the minimum concentration of bio-components in a bio-based product? At the moment this are questions that cannot be answered easily. There is no binding or at least commonly accepted definition. So every company can call its products bio-based as it pleases. She followed this up with an analysis of the types of products used on wood surfaces and the kinds of compounds often employed in these formulations. Her presentation, which more or less considered the whole picture, was followed by various others which explored the details that should lead to the vision of bio-based and sustainable coatings becoming a reality. Another important contribution to making this vision a possibility was presented by Dr Eva Tejada of Covestro. Her presentation showed the first bio-based polyisocyanate, a new solvent-free aliphatic polyisocyanate
with a significant renewable content. Covestro recently launched this new product. Others, meanwhile, are working to eradicate the need for isocyanates completely. Thus, Jan Weernink from Dow Chemical reported on isocyanate-free polyurethanes for industrial wood finishes. This polyurethane chemistry is based on the acid catalysed reaction of polycarbamates with polyaldehydes and offers the performance attributes of a high-quality urethane with the ability to decouple pot life from cure speed. However, the usage of primary alcohols like methanol or ethanol as blocking agent may dampen market penetration in Europe, because here they are considered as VOCs.

“You can learn a lot on new aspects of wood coatings. I am here to identify trends and collect ideas to develop our future coating systems in India.”
Vrijesh Kumar Sing, Asian Paints

“The benefit is that I could cover my interest at interior and exterior solutions to the chemistry of wood coatings.”
Linda Guitman, BASF
Award for Sustainable Binders
Sustainability also played an important role in the presentation of Esra Bay from Synthomer. Her presentation won the Holbrow award for the best presentation at the woodcoatings congress. She presented a green approach for more sustainable binders for interior wood coatings. She presented systems with a renewable content of up to 55% and technical properties that could mostly compete with typical acrylic binders. However, pricing stays an important issue. As important as sustainability is, naturally the “good old” performance enhancements featured prominently. In the field of interior wood coatings, there was a striking number of papers that dealt with the topic of radiation curing. Dr. Xavier Drujon from Sartomer presented an overview of the challenges facing this technology and the opportunities it offers. He looked at regulatory tightening over the last few years and how the industry had to deal with it. On the opportunities side, he proposed new raw materials that would allow for the formulation of wood coatings that would be BPA-free, non-toxic, derived from renewable resources or LED/low-energy-curable. Noteworthy on this topic is also presentation of Magdalena Bodi from Byk. She showed a new way to use silica matting agents in low gloss UV-coatings. Since UV systems do not undergo film shrinking during curing you normaly need very high dosage of silica to gain a particle distribution that gives you a certain matting. With thanks to a new core/shell structure of the silica particles Byk was able to show that this can now be achieved with a much lower amount of silica particles. There were also further developments in exterior coatings to learn about. For example, Professor Philip Evans of the University of British Columbia showed that small improvements can sometimes produce great effects. He focussed on five factors that influence clear-coating performance: the dimensional stability of the wood; the photostability of the wood surface; moisture ingress via end grain; coating flexibility and photostability; and coating thickness. This holistic approach has yielded coatings which so far have produced very good results in multi-year outdoor tests.

“The wood coatings conference is a platform to learn something new and take back to my colleagues.”
Alessandro Spagna, SherwinWilliams

“It is important to identify new technologies and trends. In my position this orientation will be necessary. Especially the presentation of innovation are interesting to me.”
IIaria Lombardi, IVM Chemicals
Need for Deeper Understanding
A big topic for exterior coatings was the lack of knowledge about the reasons for good or bad weathering performance and also the lack of standards to quantify this. As Daniel Friberg from Akzo Nobel showed, the water uptake is one very important factor. He presented new primer technologies for exterior wood coatings. The conference made clear, there is still a lot to learn and that there is a strong need for further discussions about woodcoatings. Many speakers announced that they will present follow-up results at the European Coatings Conference in Nuremberg in April 2017. And of course, there will be the 11th wood coating congress in 2018 in Amsterdam.
Created by and published in the European Coatings Journal 11 – 2016