A liquid jet recording process comprises the step of providing a continuous passageway defining a path through which liquid can flow. The passageway has an inlet thereto and an outlet orifice therefrom and further defines a thermal chamber portion located directly in the path intermediate the inlet and the outlet orifice and spaced upstream from the outlet orifice. Liquid is supplied to the passageway to fill it and an input signal is generated each time it is desired to produce a liquid droplet. The liquid in the thermal chamber portion is heated in response to each input signal and heating is sufficient instantaneously to cause a change of state of the liquid in the thermal portion chamber sufficient to produce a force acting on liquid filling the passageway between the thermal chamber portion and the orifice that overcomes the surface tension of liquid at the orifice and thereby projects a droplet of liquid from the orifice. After projection of the droplet of liquid and with attenuation of the change of state and the force produced thereby, the liquid chamber portion is replenished with liquid.
Apparatus for performing the liquid jet recording process is also disclosed.