PROBLEM TO BE SOLVED: To obtain a nozzle forming member having a high resistance to ink, enabling sure attainment of high component precision and being excellent in mass-production properties and cost reduction by forming a nozzle hole in an SUS base by etching.
SOLUTION: A nozzle plate 33 is prepared by forming a nozzle hole 38 in an SUS base 61 such as SUS 304 by etching. As for the internal shape of the nozzle hole 38, the ink liquid chamber side thereof is shaped like a horn of a large diameter, while a nozzle opening 38a of a prescribed diameter is formed by a heterogeneous metal layer 62 laminated on the ink jet face side of the SUS base 61. Moreover, a surface treated film 47 having water repellency is formed on the surface side of the heterogeneous metal layer 62. The SUS base 61 has durability in regard to ionic ink and, by enhancing the anisotropy by an etching method, it is made possible to secure also component precision and to attain mass-production properties and cost reduction. By forming the internal shape of the nozzle hole 38 like the horn, besides, it is made possible to ensure the volume of an ink droplet and to improve a discharge velocity of the ink droplet.
【解決手段】 ＳＵＳ基板６１にエッチングでノズル孔 ３８を形成した。