PROBLEM TO BE SOLVED: To provide a needleless syringe by which an injection liquid administration to a comparatively shallow area of an injection objective region of a living body or the like can more efficiently be performed, and also, of which the handling is easy.SOLUTION: A needleless syringe includes: an encapsulating part encapsulating an injection purpose substance pressurizing part pressurizing the injection purpose substance encapsulated in the encapsulating part an injection part having a path through which the injection purpose substance pressurized by the pressurizing part and injecting the injection purpose substance from an opening end of the path to an injection objective region outside the syringe a fine pore part that is a plate-like part through which fine pores having a smaller pore diameter than the pore diameter of the injection part pass from one surface to the opposite surface, and is arranged on the outside of the injection part so that the injection purpose substance injected from the injection part reaches the injection objective region side by passing through the fine pores and a holding part that holds the fine pore part arranged on the outside of the injection part from a further outer side of the fine pore part, is constituted of a member different from that of the fine pore part, includes an end surface which comes into contact with the injection objective region, and has a shape corresponding to the injection objective region at least in a part of the end surface.COPYRIGHT: (C)2013,JPO&INPIT【課題】生体等の注射対象領域の比較的浅い部位に対して注射液投与をより効率的に行え、また、取り扱いが容易な無針注射器を提供する。【解決手段】注射目的物質を封入する封入部と、封入部に封入された注射目的物質に対して加圧する加圧部と、加圧部によって加圧された注射目的物質が流れる流路を有し、該流路の開口端から注射器の外部の注射対象領域に対して注射目的物質を射出する射出部と、射出部の孔径より小さい孔径を有する微小細孔が一面から反対面に貫通した板状の微小細孔部であって、射出部から射出される注射目的物質が微小細孔を通過して注射対象領域側へ到達するように、射出部の外側に配置される微小細孔部と、射出部の外側に配置された微小細孔部を、該微小細孔部の更に外側から保持する、微小細孔部と異なる部材によって構成される保持部であって、注射対象領域と接する端面を含み、該端面の少なくとも一部が該注射対象領域に対応した形状を有する保持部と、を備える。【選択図】図1
