Borchi Kat 315 accelerates the chemical reaction between the polyol and isocyanate components of polyurethane systems, thus allowing optimal control of the curing properties, during both higher temperature and room temperature. Borchi Kat 315 ensures fast blocking stability of polyurethane coatings and provides increased film hardness, earlier solvent resistance and allows earlier sanding of the applied coating. This catalyst can be used as a replacement for tin-based products like dibutyl tin dilaurate (DBTL), in manycases yielding better coating properties than for systems catalyzed by DBTL. In particular, in many systems the use of Borchi Kat 315 results in increased film hardness at comparable drying time.