between 250 u00b0 f for 4 minutes and 380 u00b0 f for 30 seconds depending upon the dyeing media employed preferably however the process is carried out between 270 u00b0 f for 3 minutes and 290 u00b0 f for 2 minutes the annealing time can vary between 2 and 4 minutes the process of the invention is conducted in the following manner molded but otherwise untinted lenses are tinted or dyed by immersing the lens in a high boiling solvent specified in detail below containing a tinctorial amount of at least one dye the dyeing medium is maintained in a sealed container under an inert gas nitrogen being convenient to prevent dye oxidization dyeing is carried out at temperatures in the range of 250 u00b0 f to 380 u00b0 f preferably about 270 u00b0 f to 290 u00b0 f for 5 seconds up to 5 minutes depending on the depth of shade required temperature and time are inversely related i e lower temperatures require longer exposure to the dyeing medium next the lens is given an after dyeing heat treatment or annealing again in a nitrogen environment to prevent dye oxidation after annealing any non diffused dye and or high boiling solvent remaining on the lens are removed in a solvent rinse or scour for instance in a fluorinated hydrocarbon scouring medium e g freon 113 optionally containing a.