US Patent 7891783 Liquid jet head and a liquid jet apparatus

Provided is a liquid jet head including: a flow path forming substrate having formed therein a row of pressure generating chambers, each of which is communicated with a nozzle opening; a piezoelectric element which is provided in each of the pressure generating chambers via a vibration plate formed of a plurality of layers; and a bonding substrate which is bonded to a piezoelectric element forming side of the flow path forming substrate, in which: a groove is formed in a region of the vibration plate surrounding the piezoelectric element so as to extend to an interface of the plurality of layers or extend over the interface; and an insulator formed of an inorganic insulating material is formed in the groove.