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

In the field of environmentally friendly coatings waterborne two-component polyurethane systems represent a new technology, combining the good film pr operties of solventborne two-component polyurethane coatings with the low V OC values of waterborne technology. Recently, waterborne two-component poly urethane coatings have matured to the point that they offer realistic alter natives to the corresponding solventborne systems in various application fi elds. For industrial finishing and automotive refinish we are introducing rapid d rying coatings exhibiting well-balanced range of properties at low VOC leve l. We developed high-performance OEM-clearcoats which combine good chemical resistance with excellent mar resistance. Waterborne soft-feel lacquers ar e already well established in the market. Development of a new generation of water dispersible polyisocyanates as wel l 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 a nd film formation or the cause of blistering supported our developments. We expect that waterborne two-component polyurethane coatings will gain a s ignificant share of the market where high-performance coatings are demanded . (C) 2000 Elsevier Science S.A. All rights reserved.