To provide a lead-added piezoelectric film ensuring small deflection in hysteresis property and nonlinearity in comparison with the existing film, having excellent characteristics for a large piezoelectric constant in the positive direction, achieving a large displacement even in applying a positive voltage (state where a positive field is applied), for normal drive, and allowing the use of a general-purpose driving IC, to provide a method of manufacturing the same film, to provide a piezoelectric element using the same film, and to provide a liquid discharge device using the same element.

The piezoelectric film includes lead and is formed in the thickness of ≥3 μm resulting in d31(+)/d31(-)>0.5 and d31(+)>100 pm/V, and a preferable quantity of lead added to the piezoelectric film is ≤1.03. The values d31(+) and d31(-) are respectively piezoelectric constants of the piezoelectric film measured when an upper electrode and a lower electrode are formed respectively on the piezoelectric film and a positive voltage and a negative voltage are applied to the upper electrode.

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