PROBLEM TO BE SOLVED: To provide a needleless syringe capable of achieving a desired depth of injection in an injection target region of a living body, etc.SOLUTION: A projection part and a nozzle part are provided in an ejection part of the needleless syringe. The projection part projects outward so that a prescribed region including an ejection port is in contact with the injection target region when the syringe is used, and has a partition wall having a prescribed thickness. The nozzle part has a plurality of channels including ejection ports formed in the partition wall. The nozzle part is formed so that a pressurized substance to be injected flows into each of the plurality of channels, and so that distances of passage of the substance to be injected along the respective channels are approximately equal to one another.COPYRIGHT: (C)2013,JPO&INPIT【課題】生体等の注射対象領域に対して所望の注射深さを容易に実現し得る無針注射器を提供する。【解決手段】無針注射器の射出部において、注射器の使用時において射出口を含む所定の領域が注射対象領域に対して接触状態となるように外部に突出し、且つ所定の厚さを有する隔壁部を含む突出部と、隔壁部において射出口を含む流路が複数形成されたノズル部であって、該複数の流路のそれぞれは、加圧された注射目的物質が流れ込み、且つ各流路に沿った該注射目的物質の通過距離が略等しくなるように形成されたノズル部と、が設けられる。【選択図】図1
