SLEEVE FOR HYDRODYNAMIC BEARING DEVICE, HYDRODYNAMIC BEARING DEVICE EQUIPPED WITH SAME, SPINDLE MOTOR, INFORMATION PROCESSING APPARATUS, AND METHOD FOR MANUFACTURING SLEEVE FOR HYDRODYNAMIC BEARING DEVICE

摘要

A sleeve for a hydrodynamic bearing device, a hydrodynamic bearing device equipped with the sleeve, a spindle motor, information recording and reproducing and processing apparatus, and a method for manufacturing a sleeve for a hydrodynamic bearing device are provided that are capable of reducing costs through appropriate sealing treatment. The sleeve for a hydrodynamic bearing device has an inner layer and a surface layer. The inner layer is formed by sintering metal powder for sintering use. The surface layer is formed on a surface of the inner layer and includes diiron trioxide (Fe2O3). Sealing treatment is carried out by forming a surface layer including diiron trioxide (Fe2O3) on a surface of a sleeve for a hydrodynamic bearing device that is porous.