Connection structure and liquid medicine administration tool

A liquid medicine administration tool comprising:

• a medical container including a liquid medicine containing part that contains a liquid medicine and a liquid medicine discharge part through which the liquid medicine is discharged, the liquid medicine discharge part extending in an extending direction and having a central axis;
• and
• a connection structure connected to the liquid medicine discharge part, the connection structure including:
• a sealing member including a mounting part mounted to the medical container and covering an outside of the liquid medicine discharge part, an opening formed in the mounting part in an extending direction of the liquid medicine discharge part, and an elastic sealing body disposed in a space between the opening and the liquid medicine discharge part and sealing the liquid medicine discharge part, the mounting part having an outwardly facing outer periphery, the elastic sealing body having one end surface that contacts and covers the liquid medicine discharge part, the elastic sealing body having an other end surface that faces in a direction away from the one end surface;
• a connector mountable to the sealing member and including a connection needle that punctures the elastic sealing body and passes through the elastic sealing body when the connector is mounted to the sealing member, a needle hub that holds the connection needle and a guide wall that projects away from the needle hub and has an inner surface, the connection needle having a needle tip at an end of the connection needle opposite the needle hub, the connection needle also having an outer periphery;
• the connector including a push-in structure that compresses the elastic sealing body when the connector is mounted to the sealing member and the connection needle punctures the elastic sealing body;
• the push-in structure compresses the elastic sealing body in a range of a compression ratio B/A of 70% to 95% when the connector is mounted to the sealing member and when the connection needle punctures the elastic sealing body, wherein A is a volume of the elastic sealing body before puncturing with the connection needle is A and a volume of the elastic sealing body after puncturing with the connection needle is B;
• and
• the push-in structure including a protruding part possessing an outer diameter larger than an outer diameter of the connection needle, the protruding part having a first end connected to the needle hub, the protruding part also having an end portion that terminates at a second end of the protruding part opposite the first end of the protruding part, the protruding part protruding from the needle hub in a same direction as the connection needle, the second end of the protruding part being an end face of the protruding part that faces toward the needle tip of the connection needle, that extends radially away from the outer periphery of the connection needle and that is configured to contact the other end surface of the elastic sealing body when the connector is mounted to the sealing member and the connection needle punctures the elastic sealing body and passes through the elastic sealing body to compress the elastic sealing body in an axial direction of the elastic sealing body and thereby increase the compression ratio of the elastic sealing body in the axial direction, the elastic sealing body having a maximum thickness along the central axis;
• the connection needle extending, in the same direction, beyond the second end of the protruding part before the connector is mounted to the sealing member by a distance greater than the maximum thickness of the elastic sealing body;
• and
• the guide wall of the connector being fitted to and surrounding the outwardly facing outer periphery of the mounting part of the sealing member when the connector is mounted to the sealing member so that the inner surface of the guide wall faces toward and contacts the outwardly facing outer periphery of the mounting part when the connector is mounted to the sealing member, whereby the protruding part is pushed in the axial direction toward the elastic sealing body.

A method comprising:

• mounting a connector onto a sealing member that is mounted on a liquid medicine discharge part of a medical container, the medical container also including a liquid medicine containing part having an interior that contains a liquid medicine, the liquid medicine discharge part being at a distal end of the liquid medicine containing part;
• the sealing member including:
• a mounting part that is mounted to the liquid medicine discharge part in covering relation to an outside of the liquid medicine discharge part, the mounting part having an outwardly facing outer periphery;
• an opening at a distal end part of the mounting part;
• and an elastic sealing body positioned in a space between the opening and the liquid medicine discharge part to seal the liquid medicine discharge part, the elastic sealing body having one end surface that contacts and covers the liquid medicine discharge and an other end surface that faces in a direction away from the one end surface;
• the connector including:
• a needle hub;
• a connection needle in which is located a flow path, the connection needle being connected to and extending away from the needle hub, the connection needle having a needle tip at an end of the connection needle opposite the needle hub;
• a protruding part possessing an outer diameter larger than an outer diameter of the connection needle, having a first end connected to the needle hub, having an end portion that terminates at a second end of the protruding part opposite the first end of the protruding part, and protruding from the needle hub in a same direction as the connection needle, the second end of the protruding part being an end face of the protruding part that faces toward the needle tip of the connection needle and that extends away from the outer periphery of the connection needle;
• and a guide wall that projects away from the needle hub and has an inner surface;
• the mounting of the connector onto the sealing member including fitting the guide wall of the connector to the outwardly facing outer periphery of the mounting part so that the inner surface of the guide wall faces toward and contacts the outwardly facing outer periphery of the mounting part, while the protruding part of the connector is pushed in an axial direction toward the elastic sealing body;
• the mounting of the connector onto the sealing member also including puncturing the elastic sealing body with the connection needle so the connection needle passes through the elastic sealing body and so that the flow path in the connection needle is in communication with the interior of the liquid medicine containing part to permit the liquid in the interior of the liquid medicine containing part to flow into the flow path and be discharged from the interior of the liquid medicine containing part;
• and
• the end face at the second end of the protruding part contacting the other end surface of the elastic sealing body during the mounting of the connector onto the sealing member and being in contact with the other end surface of the elastic sealing body when the flow path in the connection needle is in communication with the interior of the liquid medicine containing part so that the elastic sealing body is compressed by the second end face of the protruding part resulting in the elastic sealing body being compressed in a range of a compression ratio B/A of 70% to 95%, wherein A is a volume of the elastic sealing body before puncturing with the connection needle and B is a volume of the elastic sealing body after puncturing with the connection needle, the protruding part increasing the compression ratio in the axial direction of the elastic sealing body by virtue of the end face at the second end of the protruding part contacting the other end surface of the elastic sealing body during the mounting of the connector onto the sealing member, the connection needle passing though the elastic body and being in communication with the interior of the liquid medicine containing part before the protruding part increases the compression ratio of the elastic sealing body.