Recent developments in aqueous two-component polyurethane (2K-PUR) coatings

Abstract

In the field of environmentally friendly coatings waterborne two-component polyurethane systems represent a new technology, combining the good film properties of solventborne two-component polyurethane coatings with the low VOC values of waterborne technology. Recently, waterborne two-component polyurethane coatings have matured to the point that they offer realistic alternatives to the corresponding solventborne systems in various application fields. For industrial finishing and automotive refinish we are introducing rapid drying coatings exhibiting well-balanced range of properties at low VOC level. We developed high-performance OEM-clearcoats which combine good chemical resistance with excellent mar resistance. Waterborne soft-feel lacquers are already well established in the market. Development of a new generation of water dispersible polyisocyanates as well as improvements in application technology have contributed substantially to this. Additionally, progress in understanding the fundamental principles of aqueous two-component-PUR systems like side reactions during pot life and film formation or the cause of blistering supported our developments. We expect that waterborne two-component polyurethane coatings will gain a significant share of the market where high-performance coatings are demanded.