a 1 67 polyurethane composition wt wt g a u2032 51 83 129 6 b u2032 48 17 120 6 dbp 0 20 0 64 zelec un 0 03 0 077 dbc 80 ppm 0 0198 dbp dibutylphosphate dbc di butyl tin dichloride the ingredients are placed into a side arm erlenmyer flask along with a magnetic stir bar then capped the flask is placed onto a magnetic stir plate a vacuum pump equipped with a cold trap is attached to the flask a vacuum is applied for u02dc 1 2 hours to remove any dissolved gasses this method is obvious to one skilled in the arts the monomer is carefully transferred to a separatory flask which is used to fill the molds a white meaning transparent in the context of the invention lens without polarizing film lens was cast or a polarized lens was cast with no surface treatments on the polarized wafer or a polarized lens was cast with a polarized wafer treated by a 5 naoh hydrolysis at 40 u00b0 c for 30 minutes then dried for 1 hour at 45 u00b0 c these lenses were cured in an air oven with a much longer cure cycle as follows 9 hours at about 30 u00b0 c followed by an increase in temperature from 30 to 120 u00b0 c in 5 hours and 40 minutes then maintaining at 120 u00b0 c during about 2 hours and finally a decrease of temperature from 120 u00b0.