How to improve wood coatings?
What is the secret of the perfect wood coating? “Using a wood which is stable to solar radiation could significantly extend the lifecycle of a transparent coating,” is a very important first step, says Claudio Grandoni, Coatings Coordinator for water based exterior coatings at the ICA Group.
However, “if you just consider coating performance, we will find that the glass transition temperature of the coating film is a crucial factor in exterior durability”, he adds. Grandoni beliefs that films which keep their glass transition temperatures as they age typically performe better in terms of gloss retention or cracking.
Claudio Grandoni, Coatings Coordinator for water based exterior coatings at the ICA Group.
Markus Dimmers, Head of Technical Marketing Coatings at Alberdingk-Boley, says, that in many areas there is still room for increased usage of polyurethane dispersions to achieve longer lasting finishes. “The durability of an exterior finish will benefit from the low Tg of a polyurethane which also offers high water vapour permeability, low water absorption and low to no dirt pick-up”, explains Dimmers.
Also, it is important to recognise that durability is not only determined by the topcoat. “That is the reason why we are propagating the use of polymers which will help to stabilize the lignin of the wood in order to form a more UV/weather resistant derivative of wood and polymer”, he adds.
Markus Dimmers, Head of Technical Marketing Coatings at Alberdingk-Boley
Speaking of future trends, Claudio Grandioni of ICA believes in more sustainable coatings. “We recently developed – in conjunction with DSM – the first bio-based high-performance acrylic coatings for industrial wood finishing”, he says.
Markus Dimmers from Alberdinkg Boley agrees and states: “New development will be based around lower emission systems and renewable resource materials.”
The Interview was conducted by Jan Gesthuizen
This text is a short summary of an interview that was published in the issue 7/2017 of the European Coatings Journal. The full version is available online at European Coatings 360°