Photoinitiator 2959 (4-(2-Hydroxyethoxy)phenyl Ketone, Water-Soluble)

Most standard photoinitiators (PI-184, PI-819, benzophenone) have very low water solubility (<0.01%) and require organic solvents or acrylate monomers as carriers. In waterborne UV systems (aqueous emulsions or dispersions), undissolved photoinitiator creates heterogeneous cure: the photoinitiator-rich phase cures rapidly while aqueous-phase monomers remain uncured. PI-2959 is specifically designed with a hydroxyethyl group that confers >2% water solubility, ensuring homogeneous distribution throughout the aqueous phase for consistent through-cure without organic cosolvents.