The growth of bubbles to the critical size, resulting in a volume of superheated droplets, which dispersed in high-boiling continuous medium liquid emulsion. Based on the first law of thermodynamics analysis of the formation of a new liquid-vapor interface surface and the nature of the phase transitions of the first kind in the closed medium, which is limited to the surface of the droplets of the dispersed phase. Shows the presence of factors associated with the size of the bubbles of vapor with a constant supply of heat through the interface. Presents the dependencies that fundamentally different from those describe boiling in unlimited volume fluid or near the surface of the heated wall.