| abstract |
To provide nanoparticle-containing lubricating oil compositions which impart a low coefficient of friction and can realize a further reduction in fuel cost. One of the nanoparticle-containing lubricating oil compositions comprises a lube base, an additive having a hydroxy group, and nanoparticles. Another composition comprises a lube base, an ash-free friction regulator having a hydroxy group, and nanoparticles. Still another composition comprises a lube base, an additive having a hydroxy group, and nanoparticles having a particle diameter of 1-100 nm. A further composition comprises a lube base, an ash-free friction regulator having a hydroxy group, and nanoparticles having a particle diameter of 1-100 nm. |