Study on ink ejection using focused ultrasonic wave and nozzle

摘要

Efficiency of a print head using focused ultrasonic wave and a nozzle is analyzed, and a print head operating at 10 MHz is fabricated based on the analysis. The measured sound pressure around the focal point is in good agreement with the calculated one. Ink ejection is confirmed experimentally to be generated through capillary wave. The condition necessary for ink ejection is investigated based on the wave equation of the capillary wave, and the critical value of the particle displacement of the ultrasonic wave at the focal point is predicted. The predicted value is in agreement with the experimental one.