Patent ID: 7735750

Claim:
A liquid ejection head for ejecting droplets of a solution, comprising: an ejection substrate in which multiple through-holes through which said droplets are ejected are formed; and droplet ejection means for allowing said droplets to eject through at least one of said multiple through-holes, wherein said ejection substrate includes a repellency increasing structure that comprises: a substrate having a flat surface which shows lyophilic property with respect to a liquid having a surface tension lower than that of water; and multiple recesses and/or multiple projections each having a diameter or equivalent diameter of 50 μm or less and that are formed in said surface of said substrate, wherein inner walls of said multiple recesses and/or outer walls of said multiple projections are substantially parallel to a thickness direction of said substrate, and wherein said repellency increasing structure is arranged in such a manner that a solution ejection surface of said ejection substrate around said multiple through-holes corresponds to said surface of said substrate of said repellency increasing structure in which said multiple recesses and/or said multiple projections are formed.