Microparticles containing an ultraviolet light absorbing polymer and 3- iodo -2- propynyl butylcarbamate ('IPBC') resist discoloration by sunlight and other ultraviolet light sources. Methods for preparing the microparticles produce polymer shielded , formaldehyde- free IPBC formulations which resist discoloration and leaching and are especially useful in water- based applications. The microparticles include a polymer that absorbs light over a range of ultraviolet wavelengths associated with IPBC discoloration. The microparticles may be utilized in paints, stains , stuccoes , adhesives, and plastics for example.
