text: i am looking for cooling agent that react with water. also it should be able to use for skin.? i try to make skin cooling gel. one day i heard that when this cooling agent mix or contact with water it makes water cool. and also it is able to supply on the skin.  but i do not know even it's name.  if anyone knows about this ingredient, please help me....  thank you.. anything that endothermically dissolves in water would fit the first request - i think salt would work - but it can actually cause afrost burn on bare skin, so that's probably a bad idea. also, the person would have to get wet and then put the gel on. sorry, best i could do.