Dissolve the Carbamide and the 8-hydroxyquinoline sulfate in the water. Disperse the Carbopol 941 resin in the solution with high-speed agitation. Reduce agitation and add the menthol dissolved in the propylene glycol. Continue mixing while heating to 85'C. Add the triethanolamine. Add the oil phase at 85'C while stirring. Continue stirring while cooling to 30'C.