Double crosslinking for greater efficiency
A new polyurethane solution introduces two crosslinking mechanisms to increase robustness of the system. The combination of UV and oxidative crosslinking mechanisms also improves drying times, which reduces energy consumption during application.
A new paper in the October Issue of the European Coatings Journal describes a novel polyurethane dispersion (PUD) technology for UV-curing wood coatings that can accelerate the coating process by as much as 50% thanks to faster drying.
The faster drying takes place thanks to a second oxidative crosslinking mechanism which actually increases the hydrophobicity of the coating and thus allowing earlier start of the radiation curing step.
According to the paper formulations based on the novel multi-curing PU dispersion (multi-curing PUD) ensure that coatings are sufficiently dried so that they can be exposed to UV radiation 3 to 8 minutes after application compared to 8 to 15 minutes with conventional systems.
Comparison of using standard water-borne UV-curing and new multi-curing PUD.
The second crosslinking takes place without radiation. Due to the presence of air, the crosslinking begins as soon as the first water evaporates and continues for several days. This mechanism ensures good film properties even when some areas of the coated object are not exposed to enough UV-radiation.
Further details of the new technology will be discussed during our live streamed webinar on Tuesday, 21 November at 15.00 CET. Registration is open and completely free of charge.
