Patent ID: 7311692
Filing Date: 2007-12-25
Classification: A61M

Abstract:
1. A dual-chamber type prefilled syringe comprising: a cylindrical body which has a first end provided with a portion for attaching an injection needle; a front plug member, a middle plug member and an end plug member being hermetically fitted within said cylindrical body in the mentioned order from said first end of said cylindrical body, said front plug member and said middle plug member having rear ends, respectively, on a side away from said first end; a first chamber being formed between said front plug member and said middle plug member within said cylindrical body and accommodating a first component; a second chamber being formed between said middle plug member and said end plug member within said cylindrical body and accommodating a second component; and a bypass formed on an inner surface of said cylindrical body in the shape of a concave groove, said bypass being longer than said middle plug member along an axial direction of said cylindrical body and having a rear end portion on a side away from said first end; wherein said first chamber communicates with said second chamber via said bypass when said middle plug member moves toward said first end to reach a position where said bypass is formed; and wherein an inner volume of said cylindrical body between said first end of said cylindrical body and said rear end of said front plug member when said rear end of said middle plug member has reached said rear end portion of said bypass is at least 60% of a volume of said second component and not more than said volume of said second component.