NOZZLE PLATE OF INK-JET PRINTER

PROBLEM TO BE SOLVED: To decrease interferences between projection chambers of a thermal ink-jet printing head and improve a flow characteristic of ink, by constituting a nozzle plate of a polymer or polymeric material having sufficient thickness to form an ink feed path connected to an ink feed area and feeding ink to the projection chambers. SOLUTION: After a flow feature and a nozzle hole 16 are formed of a polymeric material 18, a nozzle plate 10 is set to a semiconductor substrate 20 including an ink propeller device 22 such as a resistor heating ink in a projection chamber 14, etc. When the ink is heated by the ink propeller device 22 of a resistor type, components of the ink are evaporated rapidly to generate bubbles of steam. The bubbles formed in the projection chamber 14 press a part of the ink out from the projection chamber 14 through the nozzle hole 16. The ink collides against the semiconductor substrate 20. Since the bubbles of steam expand quickly in all directions, the bubbles extrude the ink also from a feed path 12.