US Patent 7736433 BaTiO

BaTiO3—PbTiO3 series single crystal is single-crystallized by heating BaTiO3—PbTiO3 compact powder member or sintered member having a smaller Pb-containing mol number than Ba-containing mol number, while keeping the powder or substance in non-molten condition. In this way, this single crystal can be manufactured at a crystal growing speed faster still and stabilized more, significantly contributing to improving the dielectric loss and electromechanical coupling coefficient for the provision of excellent BaTiO3—PbTiO3 series single crystal in various properties, as well as for the provision of piezoelectric material having a small ratio of lead content, which is particularly excellent in piezoelectric property and productivity.