TPO is an effective photoinitiator for UV-curable based coatings, adhesives, inks and printing plates. It is typically consumed in unsaturated polyester acrylate based systems in concentrations ranging from 1% to 4% by weight. TPO offers the advantage of good shelf stability, and fast and thorough cure of coatings. It is compatible with unsaturated polyesters, acrylate monomers and oligomers for use in UV-curable systems.