Liquid ejecting head, liquid ejecting head unit, and liquid ejecting apparatus

Abstract

A piezoelectric element including a first electrode serving as an individual electrode, a piezoelectric layer, and a second electrode serving as a common electrode is attached on a face of a flow path substrate via a vibrating plate. A piezoelectric active portion defined by the first electrode and the second electrode serving as a substantial driver of the piezoelectric element is provided in a region opposing the pressure chamber. An opening formed by removing the second electrode and the piezoelectric layer is provided in a region of the piezoelectric element opposing the partition wall. A wiring electrode and the second electrode provided on the flow path substrate are connected via a common lead electrode provided on the piezoelectric active portion, and the common lead electrode is provided at least on the partition wall inside the opening.

Description

technical field [0001] The present invention relates to a liquid ejection head, a liquid ejection head unit, and a liquid ejection apparatus that eject liquid from nozzle openings, and in particular, to an ink jet type recording head that ejects ink as a liquid, an ink jet type recording head unit, and an ink jet type recording head. recording device. Background technique [0002] Among the liquid ejection heads, there is an inkjet type recording head in which a piezoelectric element is provided via a vibrating plate on one side of a flow path forming substrate, and pressure generating chambers partitioned by partition walls are arranged in a row on the flow path forming substrate, The pressure generating chamber communicates with the nozzle opening, and the piezoelectric element is driven to cause a pressure change in the pressure generating chamber to eject ink droplets from the nozzle opening. [0003] As such an ink jet recording head, there has been proposed an ink jet...

AI Technical Summary

Problems solved by technology

[0008] However, in the case where the first electrode is formed as an individual electrode and the second electrode is formed as a common electrode as in Patent Document 1, a configuration in which the piezoelectric layer and the second electrode are continuously provided across a plurality of pressure generating chambers is considered, However, there is a problem that the continuous piezoelectric layer and the second electrode between adjacent piezoelectric elements hinder the displacement of the piezoelectric elements, so that the desired displacement characteristics cannot be obtained, that is, the generation of the so-called piezoelectric Component crosstalk (cross talk)

[0009] Therefore, when an opening is formed in the partition wall forming the pressure generating chamber without the piezoelectric layer and the second electrode, the rigidity of the partition wall decreases.

In particular, when the thickness of the partition wall becomes thinner due to the increase in the density of nozzle openings, there are problems that the rigidity of the partition wall is significantly reduced, and the partition wall is deformed due to the pressure fluctuation of the pressure generating chamber, so that the pressure fluctuation is transmitted to the phase. Adjacent pressure generation chambers, resulting in the so-called crosstalk of the partition wall that causes the ink landing position to shift or the ink ejection characteristics to decline.

Images