Provided is grease for a rolling bearing of an information recording and reproducing apparatus 1, containing a base oil, a thickener, and at least one kind of an antioxidant selected from an amine-based antioxidant (A) expressed by the General Formula (1), and a phenol-based antioxidant (B) expressed by the General Formula (2).

Hydraulic fluid and fire-resistant fluid compositions and methods of using the compositions are provided. In an embodiment, the present invention provides a method of utilizing fire-resistant fluid in hydraulic systems. For example, the method can comprise utilizing fire-resistant fluid in hydraulic systems of casters found in steel mills, in an environment where fire safety is of concern. The fire-resistant composition can comprise one or more glycerin by-products derived from a biodiesel manufacturing process. The fire-resistant composition can also comprise one or more glycerin by-products of transesterification reactions involving triglycerides. The fire-resistant fluid can be added to hydraulic systems as a solution.

The invention relates to an aqueous lubricant composition comprising at least: water; at least one polyalkylene glycol; at least one antifreeze compound selected from glycols, preferably alkylene glycols; glycerol; diglycerol; triglycerol, and mixtures thereof; at least one ascorbic acid ester; and at least one pH-regulating additive, making it possible to maintain the pH of said lubricant composition between (8) and (15). It also relates to the use of such an aqueous lubricant composition, for lubricating and/or cooling the moving parts in a mechanical system or as a hydraulic fluid. The invention also relates to the use of at least one ascorbic acid ester as an additive for improving the tribological properties of an aqueous lubricant composition.

A composition comprising water and a polyalkylene glycol having an allyl content of less than 20 eq/g, which composition has reduced foaming properties and preferably a biodegradability of at least 60% as determined using OECD 301F. The polyalkylene glycol can be made by forming a first intermediate comprising an oxypropylene block by reacting propylene oxide with a polyol initiator in the presence of a Double Metal Cyanide catalyst, and then reacting the first intermediate with ethylene oxide in the presence of a KOH catalyst.