A lubricating grease composition for extra heavy duty extreme pressure applications comprises a major amount of a synthetic base oil a lithium complex thickener, at least one extreme pressure agent; and at least 5 wt. % of molybdenum disulfide, based on a total weight of the lubricating grease composition.

A phenol derivative of the present invention has a structure as represented by the formula (I):

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The functional groups are defined in the description. The phenol derivative can be used as the antioxidant in lubricating oil, lubricating grease, plastic, rubber, or can be used as the base oil of the lubricating oil and the lubricating grease and the antiwear additive of the lubricating oil and the lubricating grease.

The invention provides a lubricating composition comprising a low viscosity base oil and a synergistic mixture of a functionalized ethylene-α-olefin copolymer, a poly(meth)acrylate polymer, and a metal-free anti-wear agent. The invention also provides a method of lubricating an internal combustion engine using such a lubricating composition.

A grease composition may be used for speed reducers and speed increasers, being excellent in both torque transmission efficiency and leak prevention performance. The grease composition may contain a base oil (A) and a urea-based thickener (B), which is used for speed reducers and speed increasers, wherein the particles containing the urea-based thickener (B) in the grease composition satisfy the following requirement (I). Requirement (I): the area-based arithmetic average particle diameter of the particles is 2.0 μm or less, as measured by a laser diffraction/scattering method.

The present invention provides a water-soluble metalworking oil composition, including: 5.0 to 20.0 mass % of a sulfur compound (A) that is one or more kinds selected from the group consisting of a sulfurized fat and oil and a sulfurized ester and has a kinematic viscosity of 10 to 800 mm.sup.2/s at 40° C.; 0.5 to 20.0 mass % of the nonionic surfactant (B) having an HLB of 6 to 18; 7.0 to 30.0 mass % of an unsaturated fatty acid polymer (C); and an amine compound (D) selected from the group consisting of a tertiary amine and a secondary amine.

The present invention relates to provision of an extreme pressure agent-containing grease composition using, as a thickener, a urea-based thickener, the grease composition being excellent in both torque transmitting efficiency and leakage prevention performance and also excellent in wear resistance and load resistance. The grease composition contains a base oil (A), a urea-based thickener (B), and an extreme pressure agent (C), wherein particles containing the urea-based thickener (B) in the grease composition satisfies the following requirement (I): Requirement (I): an arithmetic average particle diameter of the particles on an area basis as measured by the laser diffraction/scattering method is 2.0 μm or less, and the extreme pressure agent (C) is at least one selected from an organic metal-based extreme pressure agent, a sulfur-based extreme pressure agent, a phosphorus-based extreme pressure agent, and a sulfur-phosphorus-based extreme pressure agent.

The present invention relates to an aqueous lubricant composition for the lubrication of a stationary or mobile drive system, comprising at least: deionized water; at least one polyalkylene glycol; at least one antifreeze compound chosen from glycols, and at least one phosphorus compound.

It also relates to the use of this aqueous lubricant composition for the lubrication and cooling of a stationary or mobile drive system.

In metalworking, the amount of sulfur supplied is stabilized in wide temperature and pressure ranges and under an external force, such as a shear force. Thus, a stable iron sulfide film can be formed on the metal surface, and lubricity can be maintained for extended periods. Furthermore, a bulky sulfurized fat or oil with a high molecular weight can be used to form a rigid lubricating oil film with a large oil film thickness on the metal surface and thereby prevent metals from approaching each other. A sulfur-based extreme-pressure agent containing a polysulfide (a) and a sulfurized fat or oil (b) at a mass ratio in the range of 1:0.1 to 1:10. A metalworking fluid containing the sulfur-based lubricating oil composition is also related to.

In metalworking, the amount of sulfur supplied is stabilized in wide temperature and pressure ranges and under an external force, such as a shear force. Thus, a stable iron sulfide film can be formed on the metal surface, and lubricity can be maintained for extended periods. Furthermore, a bulky sulfurized fat or oil with a high molecular weight can be used to form a rigid lubricating oil film with a large oil film thickness on the metal surface and thereby prevent metals from approaching each other. A sulfur-based extreme-pressure agent containing a polysulfide (a) and a sulfurized fat or oil (b) at a mass ratio in the range of 1:0.1 to 1:10. A metalworking fluid containing the sulfur-based lubricating oil composition is also related to.

The present invention provides a water-soluble metalworking oil composition, including: 5.0 to 20.0 mass % of a sulfur compound (A) that is one or more kinds selected from the group consisting of a sulfurized fat and oil and a sulfurized ester and has a kinematic viscosity of 10 to 800 mm.sup.2/s at 40° C.; 0.5 to 20.0 mass % of the nonionic surfactant (B) having an HLB of 6 to 18; 7.0 to 30.0 mass % of an unsaturated fatty acid polymer (C); and an amine compound (D) selected from the group consisting of a tertiary amine and a secondary amine.