FLUID COMPOSITION FOR TRACTION DRIVE

To provide an additive for a traction oil and the fluid composition for the traction drive using the additive for the traction oil, wherein the additive for the traction oil maintains stable dispersion performance that functions as a cleaning dispersant even in a high temperature environment, and contains a polymer that contributes to improvement of a traction coefficient.SOLUTION: The additive for the traction oil comprises a polymer obtained by polymerizing a maleimide based monomer as a monomer component as an essential component, and has a traction coefficient reduction rate of 40% or less. Also, the fluid composition for the traction drive comprises a lubricating base oil and the additive for the traction oil. Furthermore, a method for producing the additive for the traction oil comprises a polymer obtained by polymerizing a maleimide based monomer as a monomer component as an essential component, and having the traction coefficient reduction rate of 40% or less under a specific condition.SELECTED DRAWING: None 【課題】高温環境下でも清浄分散剤として機能する安定な分散性能を維持しつつ、トラクション係数の向上にも寄与する重合体を含有するトラクションオイル用添加剤、並びに該トラクションオイル用添加剤を用いたトラクションドライブ用流体組成物を提供する。【解決手段】単量体成分として、マレイミド系単量体を必須成分として重合してなる重合体を含有し、特定条件でのトラクション係数減少率が４０％以下であるトラクションオイル用添加剤。また、潤滑油基油とトラクションオイル用添加剤を含有するトラクションドライブ用流体組成物。さらには、単量体成分として、マレイミド系単量体を必須成分として重合してなり特定条件でのトラクション係数減少率が４０％以下である重合体を含むトラクションオイル用添加剤の製造方法。【選択図】なし