Endothermic atmosphere is prepared by reacting a mixture of hydrocarbon gas, typically methane or. propane and air, metered in a proportion such that there is just enough oxygen to form carbon monoxide. and hydrogen without excess carbon dioxide or water vapor.
But for your everyday run-of-the-mill deep conditioner, it should begin to work instantly, and reach maximum capacity at around the 20 or 30 minute mark. If your deep conditioner doesn't work after 30 minutes, it's time to ditch it for one that's more effective.
How long after a perm can you wash your hair? A person should wait 24 to 48 hours after receiving a permanent hair treatment before washing her hair. If water is applied sooner than 24 hours after the perm, the chemicals can neutralize, and the hair can lose the curl. To achieve the best results, wait 48 hours.