Abstract: A rolling element bearing comprises at least two bearing rings (1, 2; 14, 15; 21, 22, 23) enclosing a bearing space (40), which bearing space (40) contains rolling elements (3, 13, 41), a cage (50, 16, 36) and lubrication structures having a porous matrix (8, 11; 17, 18; 36) containing oil and accommodated between bearing rings, cage and/or rolling elements. In order to obtain a better lubrication for an improved useful service life, the porous matrix (8, 11; 17, 18; 36) is connected to a rotatable bearing element such as a cage (50, 16, 36), a seal (4, 5) or a ring (22, 23, 24) in such a way that it does not physically contact another bearing element and that no frictional forces are generated with respect to such other bearing element, whereby upon rotation of the bearing element carrying the matrix the oil is driven through the matrix under the influence of centrifugal forces and any contaminants contained in the oil are filtered out.

Abstract: A rolling element bearing, comprising bearing rings with rolling elements between the bearing rings, and a filter seal extending between the rings for closing a space between the rings. Said filter seal is oil permeable and water repellant. Hydrophilic chemicals are grafted on the side of the filter material facing the rolling elements. The side of the filter material opposite the rolling elements is coated with a water repellant substance having a high contact angle. The filter material is a metal mesh or a microporous polymeric material.