Provided are both a grease composition for an electric power steering device and an electric power steering device. The grease composition can keep a sufficiently low coefficient of friction in a sliding area between a steel and a resin over a long period, is less susceptible to being removed from the sliding area, does not cause break down of an oil film, and thus can minimize the occurrence of stick-slips. A grease composition for an electric power steering device, containing a synthetic hydrocarbon oil which exhibits a density of 0.75 to 0.95 g/cm.sup.3 at 15 C., a saturated aliphatic amide compound, boron nitride, a glycerin fatty acid partial ester, and a metal soap-based thickener; and an electric power steering device using the grease composition.

The present invention aims to provide a viscosity index improver composition capable of providing a lubricant composition that has an excellent viscosity index improving effect, excellent antifoaming properties, and excellent persistence of the antifoaming properties. The present invention relates to a viscosity index improver composition, containing: a (co)polymer (A) containing a monomer (a) represented by the following formula (1) as an essential monomer; a C18-C40 chain aliphatic alcohol (B); and a base oil, [Chem. 1] ##STR00001##
wherein R.sup.1 is a hydrogen atom or a methyl group; X.sup.1 is a group represented by O or NH; R.sup.2 is a C2-C4 alkylene group; R.sup.3 and R.sup.4 are each independently a C8-C24 linear or branched alkyl group; and p is an integer of 0 to 20, with each R.sup.2 being optionally the same as or different from each other when p is 2 or greater.

A lubricant grease composition is disclosed, the lubricant grease composition including a base oil and a thickener. The thickener includes an aluminum-based complex soap and a polyurea thickener, wherein the lubricant grease is configured for lubrication of surfaces of components in which an upper use temperature of the lubricant grease composition is at least 90 C.

The present invention describes the highly advantageous properties of a mixture of thiol-perfluoropolyether (PFPE) molecules with perfluorinated bisphosphonic (PF-BP) compounds. This mixture makes it possible in effect to obtain a lipophobic behavior (also referred to as epilame effect) with common watch-making lubricants on all the materials tested, including metals, inter alia gold and alloys thereof, ceramics and semiconductors, and gives the surface treated a good resistance to ageing and to cleaning products.

To provide a surface treatment agent capable of imparting excellent water/oil repellency, fingerprint stain removability, abrasion resistance and lubricity to the surface of a substrate.

A surface treatment agent for a substrate, comprising a perfluoropolyether group-containing phosphate compound, a coating agent comprising the surface treatment agent and a liquid medium, and a substrate having a surface layer formed from the surface treatment agent or the coating agent.

Described herein are lubricant compositions that include combinations of lubricant additives that are effective at improving the surface finish of a range of manufactured materials and equipment. In particular, friction modifiers and antiwear additives are employed to decrease surface roughness of additive manufactured (AM), e.g., 3D printed, materials and equipment in concert with maximizing energy efficiency.

The invention provides a solid lubricant in the form of film containing a triazine compound or the salt thereof, such as melamine cyanurate or the like.

A low friction wear surface with a coefficient of friction in the superlubric regime including graphene and nanoparticles on the wear surface is provided, and methods of producing the low friction wear surface are also provided. A long lifetime wear resistant surface including graphene exposed to hydrogen is provided, including methods of increasing the lifetime of graphene containing wear surfaces by providing hydrogen to the wear surface.

Lubricating compositions are provided. The lubricating compositions can include a lubricating agent, a flexibilizer, a dispersing agent, and a charge imparting agent. The lubricating compositions can optionally include a carrier.

The present invention aims to provide a viscosity-index improving agent having an excellent friction reduction effect to reduce friction of a lubricating oil composition when the viscosity-index improving agent is added thereto. The present also aims to provide a lubricating oil composition containing the viscosity-index improving agent. The present invention relates to, for example, a viscosity-index improving agent containing: (co)polymer (A) containing, as an essential constituent monomer, a polyolefin-based monomer (a) represented by the following formula (1); an ester oil (B1) having a kinematic viscosity at 100 C. of 1.00 to 2.50 mm.sup.2/s; and an ester oil (B2) having a kinematic viscosity at 100 C. of 2.51 to 5.00 mm.sup.2/s: ##STR00001##
wherein R.sup.1 is a hydrogen atom or a methyl group; X.sup.1 is a group represented by O, O(AO).sub.m-, or NH, A is a C2-C4 alkylene group, m is an integer of 1 to 10, and each A may be the same or different when m is 2 or more; R.sup.2 is a residue after removal of one hydrogen atom from a hydrocarbon polymer containing a 1,2-butylene group as a structural unit; and p represents a number of 0 or 1.