Achieving fast-drying paints enable applicators to increase productivity
and to minimize dust issues. However, high-solid and waterborne formulations
tend to increase drying time.
High-solids polyols generally have less function features and a lower Tg
(glass transition temperature) which gives longer drying times than conventional
In order to accelerate the drying time, formulators have three options:
- Raise the curing temperature (60-80 °C)
Technical feasibility due to some applications constraints can restrain the use
of this solution
- Use a catalyst such as a tin salt (i.e. DBTL = di-butyl tin di-laurate)
But these products tend to reduce the pot-life and excess
of DBTL would also lead to lower final film hardness,
weathering resistance and higher water sensitivity.
- Use a polyol with a higher Tg and/or use a fast drying polyisocyanate