Patent ID: 7182438
Filing Date: 2007-02-27
Classification: B41J

Abstract:
1. An electrostatic ink jet head for recording an image on a recording medium by ejecting ink containing charged fine particles by use of electrostatic force generated by applying predetermined voltages to individual electrode units, comprising: a head substrate; a first drive electrode and a second drive electrode, which are formed as a double-layer electrode structure for each of said individual electrode units; an ink guide disposed on said head substrate for each of said individual electrode units; and an insulating substrate in which a through-hole is formed at a position corresponding to arrangement of said ink guide for each of said individual electrode units, wherein: said head substrate and said insulting substrate are arranged apart from each other at a predetermined interval, a flow path of the ink is formed between said head substrate and said insulating substrate, said ink guide extends through the through-hole formed in said insulating substrate, a tip end portion of said ink guide protrudes from a surface of said insulating substrate, the surface being closer to the recording medium, said first drive electrode is disposed on a side of said insulating substrate with respect to the flow path of the ink, and said second drive electrode is disposed closer to said head substrate than said first drive electrode is; and ejection/non-ejection of the ink is controlled according to a superposed voltage obtained by applying voltages of the same polarity to said first drive electrode and said second drive electrode according to image data.