PROBLEM TO BE SOLVED: To provide a disinfectant demonstrating sufficient bactericidal effect without corroding an RO membrane material, without a deteriorating in the quality of pure water and ultrapure water obtained by treatment and further, in the RO membrane treatment process of making pure water and ultrapure water and the like.SOLUTION: A reverse osmosis membrane treatment agent contains a bactericidal agent such as a halo cyanoacetamide compound and an alcoholic or glycolic organic solvent containing a specific structure 1 or structure 2 hardly capable of permeating the RO membrane. A reverse osmosis membrane treatment method using the above agent is also disclosed.COPYRIGHT: (C)2009,JPO&INPIT【課題】純水及び超純水製造等におけるRO膜処理工程において、処理して得られる純水および超純水の水質を悪化させることなく、またRO膜材質を侵すことなく、十分な殺菌効果を示す殺菌剤を提供する。【解決手段】ハロシアノアセトアミド化合物等の殺菌剤と、RO膜を透過しにくい特定の構造1または構造2を含むアルコールまたはグリコール系有機溶剤を含有することを特徴とする逆浸透膜処理剤、およびそれを用いた逆浸透膜処理方法。【選択図】なし
