Wikipedia
Fluorinert is the trademarked brand name for the line of electronics coolant liquids sold commercially by 3M. It is an electrically insulating, stable fluorocarbon-based fluid, which is used in various cooling applications. It is mainly used for cooling electronics. Different molecular formulations are available with a variety of boiling points, allowing it to be used in "single-phase" applications, where it remains a liquid, or for "two-phase" applications, where the liquid boils to remove additional heat by evaporative cooling. An example of one of the compounds 3M uses is FC-72 (perfluorohexane, CF). Perfluorohexane is used for low-temperature heat-transfer applications due to its boiling point. Another example is FC-75, perfluoro(2-butyl-tetrahydrofurane). There are 3M fluids that can handle up to , such as FC-70 (perfluorotripentylamine).
Fluorinert is used in situations where air cannot carry away enough heat, or where airflow is so restricted that some sort of forced pumping is required.