The Waterborne Symposium

A special measuring geometry, rotating at low constant angular velocity through a paint film, was developed to record the increase of torque during drying under constant temperature and humidity conditions, thus giving access to a qualitative and quantitative differentiation of additives regarding their impact on the drying behavior of the paint.  A series of additives with different hydrophilic lipophilic balance values was tested in two paints, an acrylic lacquer with a pigment volume concentration of 36.2% and an indoor/outdoor dispersion paint with a pigment volume concentration of 78.6%.  Interestingly, the additive performance was found to be dependent on the paint composition, suggesting that specific interactions between the additives and the paint ingredients are mainly responsible for influencing the drying process.  This method represents an interesting alternative for additive testing and identification of the best choice to achieve the desired impact on the drying behavior of waterborne dispersion paints.