[Challenge] A method of coating the inside of polyvinyl chloride medical tubing containing a plasticizer, an anti-thrombotic material comprising a specific (meth) acrylate copolymer, without causing coating irregularity and poor appearance due to dissolution of the plasticizer I coated with a sufficient amount of uniform and efficiently in a simple manner the anti-thrombotic material. [MEANS FOR SOLVING PROBLEMS] The copolymer constituting the anti-thrombotic material is soluble but through the inside of the tube a solution of the anti-thrombogenic material in a solvent consisting of at least one alcohol and water, which was prepared as is insoluble plasticizers After allowing the solution, and allowed to flow through followed by water, and then dried. [Selection] Figure Figure 1【課題】特定の(メタ)アクリレート共重合体からなる抗血栓性材料を、可塑剤を含むポリ塩化ビニル製医療用チューブの内側にコーティングする方法において、可塑剤の溶出による外観不良やコーティングムラを起こさずに抗血栓性材料を簡便な方法で効率良く均一かつ十分な量でコーティングする。【解決手段】抗血栓性材料を構成する共重合体が可溶であるが可塑剤が不溶であるように調製した水と少なくとも1種のアルコールからなる溶媒に抗血栓性材料を溶解した溶液をチューブ内部に通液させた後に、続いて水を通液させ、その後乾燥する。【選択図】図1
