An ink jet printing head which prints image data with ink droplets without impairing print quality or causing the recording paper to be excessively wetted. The ink jet recording head includes pressure producing chambers communicating with nozzle openings, and piezoelectric vibrating elements for expanding...http://www.google.com.au/patents/US5552809?utm_source=gb-gplus-sharePatent US5552809 - Method for driving ink jet recording head and apparatus therefor
