Two component polyurethane finishes will cure as quickly as the hydroxyl groups and the isocyanate groups react with each other and form a crosslinked matrix. The speed of these reactions depends on several things – temperature, accessibility of the one functional group to the other, and the amount of catalyst in the formulation. Catalysts are an important ingredient, as they allow the formulator to fine tune their formulation so that the speed of dry is as fast as desired but not so fast as to burden the applicator. The standard rule of thumb level of the dibutyltin dilaurate catalyst, an industry standard since the emergence of this technology, is 0.005% (based on total resin solids). However, it is a common mistake to assume that all polyols behave the same during this curing/crosslinking process. LUMIFLON polyols are no exception. When choosing the level of catalyst for your LUMIFLON formulation, I would start at a catalyst level that is 0.0005% (based on resin solids) and adjust it if necessary to meet the pot life expectations of your customer. If you are working with non-tin catalysts, make sure you start at the lowest recommended level and adjust from that point. Also, I would run a stability test on your finished formulation to make sure that the catalyst of choice will not seed out or lose its effectiveness as the coating ages. AGC Chemicals will work with our customers to choose the right catalyst for their specific application.
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