BYK® -425

BYK® -425 by BYK is a solution of a urea modified polyurethane. Acts as a rheology control agent. Its efficiency results from the interactions between the additive and the resin, pigments and extenders of the formulation. Additionally, the urea modification of the additive enhances the rheological efficiency based on hydrogen bonding capabilities. It is liquid, VOC- and APEO- free. It does not require pH-value adjustment for rheology effect. BYK® -425 improves sag resistance, anti-settling properties. It is designed for adjusting the low shear viscosity of aqueous and water soluble resin systems providing pseudoplastic flow behavior. Due to its high effectiveness it is also suitable to increase in-can viscosity and to adjust flow properties of pigment pastes. In order to optimize the viscosity during the dispersing phase it is recommended adding it to the mill base. Its recommended level based upon total formulation is 0.1 - 1.5%.