POROUS SOLID LUBRICANT, BEARING, AND CONSTANT VELOCITY UNIVERSAL JOINT

摘要

A solid lubricant which is improved in the ability to retain a lubricating oil therein and in which the amount of the lubricating oil oozing out due to a deformation caused by external force can be reduced to a minimum necessary amount; and a bearing or constant velocity universal joint containing the lubricant enclosed therein. The porous solid lubricant comprises a lubricating component comprising a lubricating oil and a resin component as essential components, wherein the resin component is a solid matter having porosity imparted thereto by foaming and the lubricating component is occluded in the resin. Since the lubricating component is occluded in the resin in a foamed state, the resin, which is flexible, deforms upon reception of an external force, e.g., compression, expansion, flexing, or torsion, to ooze out the lubricating component. Thus, the lubricating component is gradually released from spaces among the molecules of the resin. The amount of the lubricating oil which can be retained is larger than that of the lubricating oil held by mere infiltration into the pores. With the lubricant, the bearing can have a long life, can be operated even at a high revolution, and can be produced at low cost. Furthermore, the constant velocity universal joint can have a long life and be reduced in damage to the boot made of rubber.