The syringe assembly 10 of the present invention includes an outer cylinder 2 and a seal cap 3. The outer cylinder includes an outer cylinder main body portion 21, a puncture needle attachment portion 22, and a puncture needle 6 fixed to the puncture needle attachment portion. The seal cap 3 includes a closed distal end portion 31, an opening proximal end portion 32, a puncture needle attachment portion accommodation portion 35 that accommodates the distal end portion of the puncture needle attachment portion, a puncture needle accommodation portion 34, and a puncture needle tip. And an enterable portion 33. A polyparaxylylene coating is provided on the inner surface of the puncture needle mounting portion storage portion of the seal cap or the outer surface of the puncture needle mounting portion of the outer cylinder, and both are in close contact via the polyparaxylylene coating. .本発明のシリンジ用組立体１０は、外筒２と、シールキャップ３とからなる。外筒は、外筒本体部２１と、穿刺針取付部２２と、穿刺針取付部に固定された穿刺針６とを備える。シールキャップ３は、閉塞先端部３１と、開口基端部３２と、穿刺針取付部の先端部を収納する穿刺針取付部収納部３５と、穿刺針収納部３４と、穿刺用針先の刺入可能部３３とを備える。シールキャップの穿刺針取付部収納部の内面または外筒の穿刺針取付部の外面には、ポリパラキシリレン被膜が設けられ、かつ、両者は、ポリパラキシリレン被膜を介して密着している。
