A lubricating oil composition for an internal combustion engine including: (A) a lubricant base oil having a kinematic viscosity at 100° C. of 2 to 5 mm.sup.2/s; (B) a metallic detergent in an amount of 500 to 2500 mass ppm in terms of Ca and 100 to 1000 mass ppm in terms of Mg, on the basis of the total mass of the composition, the metallic detergent including both (B1) a Ca-containing metallic detergent and (B2) a Mg-containing metallic detergent; (C) a boron-containing additive in an amount of 50 to 1000 mass ppm in terms of boron on the basis of the total mass of the composition, wherein the boron-containing additive is oil-soluble or oil-dispersible and is stable in oil, and wherein the boron-containing additive may compose at least a part of the component (B); and (D) an oil-soluble organic Mo compound in an amount of 100 to 2000 mass ppm in terms of Mo on the basis of the total mass of the composition, wherein a mass ratio (MB/Mg) of boron content of the composition (MB) to Mg content of the composition (Mg) is 0.5 to 10.

A super-lubricity water lubricating additive, a super-lubricity water lubricant, a preparation method and application, wherein the additive is of a hollow spherical shell structure which includes at least one layer of spherical shell; the spherical shell sequentially includes a first polydopamine layer, a nanoparticle layer, a second polydopamine layer and an oxidized graphene layer from inside to outside, or a first polydopamine layer, a nanoparticle layer, a second polydopamine layer, a graphene layer and a third polydopamine layer from inside to outside; and nanoparticles of the nanoparticle layer are nano diamond, nano molybdenum disulfide or nano tungsten disulfide. The additive is prepared into a uniform aqueous solution to obtain the super-lubricity water lubricant. The additive can be easily adsorbed on a dual surface, and the nanoparticles released in a friction process cooperate with spherical oxidized graphene or graphene to form rolling friction so as to reduce frictional abrasion.

A super-lubricity water lubricating additive, a super-lubricity water lubricant, a preparation method and application, wherein the additive is of a hollow spherical shell structure which includes at least one layer of spherical shell; the spherical shell sequentially includes a first polydopamine layer, a nanoparticle layer, a second polydopamine layer and an oxidized graphene layer from inside to outside, or a first polydopamine layer, a nanoparticle layer, a second polydopamine layer, a graphene layer and a third polydopamine layer from inside to outside; and nanoparticles of the nanoparticle layer are nano diamond, nano molybdenum disulfide or nano tungsten disulfide. The additive is prepared into a uniform aqueous solution to obtain the super-lubricity water lubricant. The additive can be easily adsorbed on a dual surface, and the nanoparticles released in a friction process cooperate with spherical oxidized graphene or graphene to form rolling friction so as to reduce frictional abrasion.

A method is provided that forms a solid film on a bearing component of a rolling bearing. A solution containing a fluorine compound and a lubricant having no functional group is allowed to adhere to the bearing component as a first liquid film (adhesion step). The adhering first liquid film is hardened to form the solid film on the bearing component. The rolling bearing including the bearing component with the solid film formed thereon is rotated. The rolling bearing is washed in a washer fluid containing the same lubricant as that used in the adhesion step, and the washer fluid is allowed to adhere to the bearing component as a second liquid film. Then, the adhering second liquid film is dried.

The invention is directed to a method for reducing low speed pre-ignition events in a spark-ignited direct injection internal combustion engine by supplying to the sump a lubricant composition which contains an oil of lubricating viscosity and an ashless dispersant. The ashless dispersant may be selected from succinimide compounds prepared from aliphatic or aromatic amines.

The invention is directed to a method for reducing low speed pre-ignition events in a spark-ignited direct injection internal combustion engine by supplying to the sump a lubricant composition which contains an oil of lubricating viscosity and an ashless dispersant. The ashless dispersant may be selected from succinimide compounds prepared from aliphatic or aromatic amines.

The disclosure relates to a coating composition comprising a polymerizable compound of formula [1], wherein G is a residue of a hydrophobic hydroxy-functional oligomer, n is 1-10, each R1 independently is a residue of a C.sub.6-C.sub.20 aliphatic, cycloaliphatic, or aromatic hydrocarbon compound, and Z is a moiety having a polymerizable group; Formula [1] a hydrophilic polymer; a photo-initiator; optionally one or more further components, and a solvent. The polymerizable compound of formula [1] is typically present in an amount of 2.0-30 mass % based on total dry mass of the composition. Such coating composition can be made into a well-adhering single-layer hydrophilic coating on a surface of polymer substrates without providing a primer layer or chemically modifying the surface of the substrate. Upon wetting, the coating shows excellent lubricity and durability. In further aspects, the disclosure provides a method of applying a hydrophilic and optionally lubricious coating to an article; and an article like a medical device having on at least part of its surface a single-layer, hydrophilic and optionally lubricious coating, like a catheter, guidewire, or a delivery device for an implant.

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The disclosure relates to a coating composition comprising a polymerizable compound of formula [1], wherein G is a residue of a hydrophobic hydroxy-functional oligomer, n is 1-10, each R1 independently is a residue of a C.sub.6-C.sub.20 aliphatic, cycloaliphatic, or aromatic hydrocarbon compound, and Z is a moiety having a polymerizable group; Formula [1] a hydrophilic polymer; a photo-initiator; optionally one or more further components, and a solvent. The polymerizable compound of formula [1] is typically present in an amount of 2.0-30 mass % based on total dry mass of the composition. Such coating composition can be made into a well-adhering single-layer hydrophilic coating on a surface of polymer substrates without providing a primer layer or chemically modifying the surface of the substrate. Upon wetting, the coating shows excellent lubricity and durability. In further aspects, the disclosure provides a method of applying a hydrophilic and optionally lubricious coating to an article; and an article like a medical device having on at least part of its surface a single-layer, hydrophilic and optionally lubricious coating, like a catheter, guidewire, or a delivery device for an implant.

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A water-based lubricating grease composition includes at least 40 wt % water; a salt-based thickener; a polymer-based thickener; and optionally, an inorganic solid-based thickener. A process for preparing the water-based lubricating grease composition may include blending a suitable amount of water with a salt-based thickener to provide a thickened water-based grease, wherein the salt-based thickener is obtained from contacting a base with a fat; and adding a polymer-based thickener to the thickened water-based grease.

Lubricant compositions including an additive composition and methods for its use in engines that produce soot. The lubricant composition contains a base oil and an additive composition having (a) at least 0.05 percent by weight of a first dispersant that is a reaction product of A) a hydrocarbyl-dicarboxylic acid or anhydride, and B) at least one polyamine; and (b) at least 0.05 percent by weight, both based on a total weight of the lubricant composition, of a second dispersant that is a reaction product of A′) a hydrocarbyl-dicarboxylic acid or anhydride, and B′) at least one polyamine, wherein the reaction product is post-treated with C) an aromatic carboxylic acid, an aromatic polycarboxylic acid, or an aromatic anhydride wherein all carboxylic acid or anhydride groups are attached directly to an aromatic ring, and/or D) a non-aromatic dicarboxylic acid or anhydride having a number average molecular weight of less than about 500.