The invention provides a grease composition for lubricating resins which contains a base oil, a diurea compound represented by formula (I) as a thickener: R.sup.1NHCONHR.sup.2NHCONHR.sup.3 (I) (wherein R.sup.2 represents a bivalent aromatic hydrocarbon group having 6 to 15 carbon atoms, and R.sup.1 and R.sup.3 each independently represent a straight-chain or branched alkyl group having 8 to 22 carbon atoms), and a chained hydrocarbon polymer having a weight-average molecular weight of 20,000 to 300,000.

An electrorheological fluid which comprises a dispersion medium containing fluorine atoms in an amount larger than 0 wt % but not larger than 50.0 wt % and particles for electrorheological fluid use that are contained in the dispersion medium in an amount of 10-50 vol % of the total volume of the dispersion medium and the particles, the particles comprising a sulfonic-acid-group-containing polymer having a sulfonic acid group content of 30-70 wt %.

An electrorheological fluid which comprises a dispersion medium containing fluorine atoms in an amount larger than 0 wt % but not larger than 50.0 wt % and particles for electrorheological fluid use that are contained in the dispersion medium in an amount of 10-50 vol % of the total volume of the dispersion medium and the particles, the particles comprising a sulfonic-acid-group-containing polymer having a sulfonic acid group content of 30-70 wt %.

Various liquid and semisolid lubricant compositions are provided, in particular lubricant compositions containing oil from the seeds of the Brassicaceae Orychophragmus violaceus, preferably those that have been esterified with one or more fatty acids such as palmitoleic acid, oleic acid, linoleic acid, lauric acid, palmitic acid, stearic acid, or a combination thereof. In various aspects, lubricant compositions are provided that include a petroleum or a synthetic base oil and about 40% or less by weight of a liquid lubricant composition containing oil from the seeds of the Brassicaceae Orychophragmus violaceus, preferably those that have been esterified with one or more fatty acids. In various aspects, semisolid lubricant composition are provided containing an emulsion of (i) a thickener and (ii) an oil from the seeds of the Brassicaceae Orychophragmus violaceus, preferably those that have been esterified with one or more fatty acids.

The present invention relates to a lubricating oil composition containing a base oil (A) and a viscosity index improver (B) such that in X-ray small-angle scattering spectra obtained through measurement at 40 C. and 100 C., a ratio [|(40)|/|(100)|] between |(40)| and |(100)|, each of which is an absolute value of a slope of a straight line calculated in a range of the scattering vector q as the x axis of from 0.1 nm .sup.1 to 1 nm .sup.by the least-squares method, is 1.5 or more.

The present invention relates to a lubricating oil composition containing a base oil (A) and a viscosity index improver (B) such that in X-ray small-angle scattering spectra obtained through measurement at 40 C. and 100 C., a ratio [|(40)|/|(100)|] between |(40)| and |(100)|, each of which is an absolute value of a slope of a straight line calculated in a range of the scattering vector q as the x axis of from 0.1 nm .sup.1 to 1 nm .sup.by the least-squares method, is 1.5 or more.

The present invention relates to an electric discharge machining oil composition and an electric discharge machining method capable of enhancing machining speed in electric discharge machining. This electric discharge machining oil composition is characterized by including (A) a base oil, and (B) one or more types of petroleum resin selected from hydrogenated products of copolymers of dicyclopentadiene and an aromatic compound and having a softening point of 75 to 185 C. and a mean molecular weight (Mn) of 670 to 3000, wherein the kinematic viscosity of the electric discharge machining oil composition at 40 C. is 1 to 10 mm.sup.2/s. Further, the electric discharge machining method is characterized by employing said electric discharge machining oil composition, and includes interposing the electric discharge machining oil composition between a workpiece and an electrode, and generating an electric discharge between the workpiece and the electrode in this state to machine the workpiece.

The present invention relates to an electric discharge machining oil composition and an electric discharge machining method capable of enhancing machining speed in electric discharge machining. This electric discharge machining oil composition is characterized by including (A) a base oil, and (B) one or more types of petroleum resin selected from hydrogenated products of copolymers of dicyclopentadiene and an aromatic compound and having a softening point of 75 to 185 C. and a mean molecular weight (Mn) of 670 to 3000, wherein the kinematic viscosity of the electric discharge machining oil composition at 40 C. is 1 to 10 mm.sup.2/s. Further, the electric discharge machining method is characterized by employing said electric discharge machining oil composition, and includes interposing the electric discharge machining oil composition between a workpiece and an electrode, and generating an electric discharge between the workpiece and the electrode in this state to machine the workpiece.

Phase change material compositions and methods for using the compositions to prepare substrate coatings or bulk blended polymers that advantageously lower friction between interacting substrate surfaces and lower substrate surface wear.

Compositions are obtained by mixing at least one oligomer A1, which is obtained by copolymerizing at least two monomers functionalized by diol functions with at least one second monomer, with at least one compound A2 having at least two boron ester functions. The compositions exhibit very varied rheological properties depending on the proportion of the compounds A1 and A2 used. A composition is also obtained by mixing at least one lubricating oil with such a composition of associative and exchangeable polymers, and the use of this composition to lubricate a mechanical part.