Abstract: A lubricating fluid composition for dynamic pressure bearings which supports a shaft by dynamic pressure, said lubricating fluid composition comprising fine magnetic particles dispersed in a base oil solvent, to which solvent is added an amine anti-gelling agent.

Abstract: A fluid bearing unit includes a shaft; a bearing; bearing fluid arranged between a shaft and a bearing which are rotatably engaged with each other so that they can be relatively rotated so as to generate dynamic pressure in the bearing fluid, wherein at least one of the bearing and the member for fixing the bearing unit is made of iron alloy having the volumetric magnetostriction of which acts to cancel the thermal expansion so as to become the coefficient of linear expansion thereof lower than that of the shaft.

Abstract: A lubricating fluid composition for dynamic pressure bearings which supports the shaft of the bearing by dynamic pressure, wherein the lubricating fluid composition comprises fine magnetic particles dispersed in a base oil solvent which comprises a hydrogenated poly-.alpha.-olefin (PAO) and a polyol ester.

Abstract: A polyarylene sulfide resin composition having an excellent fluidability and a good moldability is disclosed. The resin composition is useful as a material for an optical pick-up part which has a high reliability and a high tenacity and does not generate deviation of an optical axis with changes in environmental conditions such as temperature and humidity. The polyarylene sulfide resin composition comprises, as main components, a polyarylene sulfide resin, a fibrous filler and a particulate filler, and, optionally, a silane coupling agent and an alicyclic hydrocarbon.