US Patent 7524039 Liquid ejection head and image forming apparatus

The liquid ejection head comprises: a pressure chamber which is connected to an ejection port ejecting liquid, the liquid being supplied to the pressure chamber from a supply flow channel; and a piezoelectric element which forms a wall surface of the pressure chamber facing to the ejection port, wherein, during liquid ejection, the liquid inside the pressure chamber is pressurized by means of displacement of the piezoelectric element in d33 direction, and a gap formed between a partition of the pressure chamber and the piezoelectric element is made narrower than during refilling, in such a manner that flow resistance of the liquid from the pressure chamber toward the supply flow channel becomes greater than during refilling.