Patent ID: 7498726

Claim:
A multilayer piezoelectric element comprising a laminate body in which a plurality of piezoelectric bodies and a plurality of internal electrodes are alternately laminated and simultaneously sintered, wherein the plurality of internal electrodes comprise a first electrode and a second electrode, wherein the laminate body has: an active portion in which the first electrode and the second electrode are arranged to overlap in a laminate direction of the laminate body; and inactive portions which are provided on both sides of the active portion and in which the first electrode and the second electrode are arranged not to overlap in the laminate direction of the laminate body, wherein the inactive portions are provided with a metal oxide layer formed of a material having a melting point higher than a sintering temperature of the piezoelectric bodies and being soluble in the piezoelectric bodies, the metal oxide layer being laminated in, and in parallel with, the plurality of piezoelectric bodies, the metal oxide layer extending in both at least a part of the active portion and at least a part of the inactive portions, and the metal oxide layer overlapping, in the laminate direction, both at least a part of the first electrode and a part of the second electrode, and wherein the metal oxide layer is simultaneously sintered with the plurality of piezoelectric bodies.