PURPOSE: To miniaturize a head and to increase the density of nozzles, by integrally constituting the parts corresponding to conventional nozzles and pressure chamber so as to oppose the groove provided to a vibration unit to a fixing substrate.

CONSTITUTION: In vibration unit 1, a piezoelectric element 1a and an elastic plate 1b are bonded to each other and the elastic plate 1b is arranged in opposed relation to a fixing substrate 11 and one end thereof is fixed to and supported on the fixing substrate 11 at a fixing part 7 so as to bring the vibration unit 1 to a cantilevered beam. Further, a groove 10 composed of a slit or notch extending from the free end of the vibration unit 1 toward the fixed end thereof is provided to said unit 1 on the side of the elastic plate. Therefore, when a printing signal V is applied to the vibration unit 1, the vibration unit 1 is displaced in a direction separated vertically on the free end side thereof with respect to the surface of the fixing substrate 11 and a recording liquid 5 is supplied to a pressure chamber 2 in the amount equal to the volumetric increment generated at this time from a recording liquid supply passage 12.