Rolling bearing for air turbine

A rolling bearing for an air turbine comprising:

• an outer ring;
• an inner ring;
• a plurality of rolling bodies rollably disposed between the outer ring and the inner ring;
• and
• a substantially annular seal member provided in one axial end portion of a bearing internal space between the outer ring and the inner ring and made of an elastic body without a core metal, wherein
• an outer peripheral portion of the seal member is fixed by a retaining ring to a groove portion formed on an inner peripheral surface of the outer ring in the one axial end portion and an inner peripheral portion of the seal member is elastically deformable,
• the one axial end portion is on a side opposite to an inlet of compressed air supplied to the bearing internal space,
• the seal member includes an inclined portion inclined toward one axial end portion side on an inner diameter side, and
• the seal member satisfies 0.25≤Skn/Skt≤2.5 when Skn is a radial length from an inclination start part of the inclined portion on an inside in an axial direction to an outermost diameter position of a part of contact of the seal member with an outer peripheral surface of the inner ring and Skt is a thickness of the inclined portion in a direction perpendicular to an inclination direction.