LiWa Iso is a liquid based on 2-butanone which and can be used to insulate gypsum models against the light-curing resin LiWa. LiWa Iso consists of two liquids, Step I and Step II which have to be applied successively. LiWa Iso Step I penetrates the gypsum and LiWa Iso Step 2 seals the surface. After curing, LiWa Iso prevents the light-cuing LiWa resins from sticking to the model