PROBLEM TO BE SOLVED: To provide a long-time injection device which is installed, for example, on the skin surface, which can inject a drug solution such as insulin into the skin over a long time, and which employs a simple and inexpensive constitution in particular.SOLUTION: The long-time injection device is characterized by including: a case a microneedle which is disposed in the state of protruding from the case and provided with an outflow port a drug solution filling portion which communicates with the outflow port and the inside of which is filled with the drug solution a piston which is provided inside the case and which pushes out the drug solution, infilled into the drug solution filling portion, to the side of the outflow port an elastic member which is provided inside the case and which constantly urges the piston in a drug solution push-out direction and a spacer which is provided inside the case, which regulates the movement of the piston in the drug solution push-out direction by the elastic member, and which has its own state gradually changed by environmental changes, so as to gradually permit the movement of the piston in the drug solution push-out direction.COPYRIGHT: (C)2012,JPO&INPIT【課題】 例えば、皮膚表面に設置され、長時間にわたってインシュリンなどの薬液を皮膚内に注射することができる長時間注射装置に係り、特に、簡易且つ安価な構成となる長時間注射装置を提供すること。【解決手段】 ケースと、ケースから突出・配置され流出口が設けられたマイクロニードルと、流出口と連通しその内部に薬液が充填される薬液充填部と、ケース内部に設けられ薬液充填部内に充填された薬液を上記流出口側へ押し出すピストンと、ケース内部に設けられピストンを薬液を押し出す方向に常時付勢する弾性部材と、ケース内部に設けられ弾性部材によるピストンの薬液の押し出し方向への移動を規制し環境変化により自身の状態が徐々に変化することによりピストンの薬液の押し出し方向への移動を漸次許容するスペーサと、を具備することを特徴とする長時間注射装置。【選択図】図6
