Ink jet printing head which prevents the stagnation of ink in the vicinity of the nozzle orifices

Abstract

In an ink jet print head, a fluid passage forming substrate includes pressure generating chambers being trapezoidal in shape, each pressure generating chamber having walls substantially parallel to the flowing direction of ink, and no stagnation of ink is present in the pressure generating chambers. The pressure generating chambers' walls include first walls vertical to the surface of the silicon monocrystalline substrate and oriented in the orientation of the pressure generating chambers, and second walls slanted at an angle of 35° with respect to the surface of the substrate, the second walls being formed at both ends of each pressure generating chamber. An elastic plate is fastened onto first opening-formed sides of the pressure generating chambers and piezoelectric layers for expanding and contracting the pressure generating chambers are mounted on the surface of the elastic plate. A covering member has nozzle openings each located at the end of each pressure generating chamber which are firmly fastened to second opening-formed sides of the pressure generating chambers. The covering member is firmly fastened on the fluid passage forming substrate by an adhesive layer.