THE CHOLESTERIC-ISOTROPIC-BLUE PHASE TRIPLE POINT

An observation that the entire blue phase temperature range for cholesteric mixtures with half-pitch less than 2200A is comparable to the range of temperature over which the cholesteric and isotropic liquid coexists when the pitch is greater than 2200A is reported describing the cholesteric-isotropic-blue phase triple point. The batonnets which the larger pitch cholesteric phase nucleates become unstable with respect to the smaller pitch blue phase isotropic mixture. These observations lend support to our previously proposed model that blue phases are cholesteric-isotropic emulsions which are only stable when the pitch is less than 2500A.