PIEZOELECTRIC ELEMENT, AND PIEZOELECTRIC MEMBER, LIQUID DISCHARGE HEAD, AND RECORDING DEVICE USING PIEZOELECTRIC ELEMENT

摘要

The present invention aims at providing a piezoelectric element with less characteristic variations with time, and a liquid discharge head and a recording device each using the piezoelectric element. The piezoelectric element 30 of the present invention is the piezoelectric body 30 (piezoelectric ceramic layer 21b) containing a potassium sodium niobate composition as a primary component. The piezoelectric body extends in a planar direction. A compressive stress is applied in the planar direction. A phase transition point between a tetragonal crystal system and an orthorhombic crystal system is -20°C or below.