PROBLEM TO BE SOLVED: To provide a medical rubber, capable of controlling an infinitesimal liquid medicine injection even when an eluted component due to contact with the liquid medicine is almost not existed and the rubber is used for the sealing material of a liquid medicine injector, and the liquid medicine injector using the same.SOLUTION: The medical rubber comprises a rubber-like elastic unit, and a film of an aromatic polymer compound or of a heterocyclic polymer compound covering the surface of the elastic unit. In this rubber, the thickness of the film is 0.01 to 0.08 &mum. The liquid medicine injector comprises the medical rubber inserted into an outer cylinder made of a polyolefin to cove the distal end of a plunger moving in the cylinder and used as a sealing material for sealing between the inner wall of the cylinder and the outer wall of the plunger.COPYRIGHT: (C)2002,JPO【課題】 薬液との接触による溶出成分がほとんどなく、しかも薬液注入器のシール材に用いた場合であっても、微量な薬液注入コントロールができる医療用ゴム及びこれを用いた薬液注入器を提供する。【解決手段】 ゴム状弾性体と、該ゴム状弾性体の表面を被覆する芳香族系高分子化合物又は複素環系高分子化合物の被膜とを有し、且つ該被膜の厚みが0.01μm~0.08μm以下の医療用ゴム。本発明の薬液注入器は、この医療用ゴムを、ポリオレフィン製外筒体に挿入され、該外筒体内を移動するプランジャの先端に被着し、該外筒体内壁と該プランジャ外壁との間をシールするシール材として用いる。
