Retainer for roller bearing, and rolling bearing

A rolling bearing, comprising an inner ring having a rolling surface on a peripheral surface thereof;

• an outer ring, having a rolling surface on an inner peripheral surface thereof, which is disposed concentrically with said inner ring;
• a plurality of rolling elements disposed between said both rolling surfaces;
• and a retainer holding a plurality of said rolling elements,
• wherein said retainer comprises a molding, of a synthetic resin composition, which holds a rolling element of a rolling bearing,
• wherein said molding comprises a resinous porous article having an interconnected hole porosity not less than 30% and a lubricating oil which impregnates said resinous porous article,
• wherein said resinous porous article is formed by molding a resin containing a pore-forming substance incorporated therein, and by extracting said pore-forming substance from said molding with a solvent which dissolves said pore-forming substance and does not dissolve said resin
• which is used for a vacuum apparatus used in an atmosphere having a pressure not more than 1.0×10−4 Pa.