A process for making a poly alpha-olefin (PAO) having high vinylidene content (or combined vinylidene and tri-substituted vinylene content) and low vinyl and/or di-substituted vinylene content, as well as a relatively low molecular weight comprising contacting a feed containing a C.sub.6-C.sub.32 alpha-olefin with a catalyst system comprising non-aromatic-hydrocarbon soluble activator and a metallocene compound, typically a cyclopentadienyl-tetrahydro-s-indacenyl group 4 transition metal compound.

The present invention relates to a saturated aliphatic hydrocarbon compound composition having an evaporation loss of 4% by mass or less as determined by the Noack method, a kinetic viscosity at 100° C. of 6.5 mm.sup.2/s or less, and an average carbon number of 36 to 44, to a lubricating oil composition containing the saturated aliphatic hydrocarbon compound composition, and to a method for producing a saturated aliphatic hydrocarbon compound composition, including: a step 1 of oligomerizing an olefin to obtain an olefin oligomer; a step 2 of isomerizing the olefin oligomer to obtain an isomer; and a step 3 of hydrogenating the isomer.

A lubricating grease composition containing a base oil having a kinematic viscosity of 10 mm.sup.2/s or more and 60 mm.sup.2/s or less at 40° C.; a thickener containing at least one soap selected from a metal soap and a metal complex soap; and a solid lubricant containing porous polyamide particles. An amount of the porous polyamide particles blended is 1% by mass or more and 20% by mass or less based on a total mass of the lubricating grease composition.

A lubricating grease composition containing a base oil having a kinematic viscosity of 10 mm.sup.2/s or more and 60 mm.sup.2/s or less at 40° C.; a thickener containing at least one soap selected from a metal soap and a metal complex soap; and a solid lubricant containing porous polyamide particles. An amount of the porous polyamide particles blended is 1% by mass or more and 20% by mass or less based on a total mass of the lubricating grease composition.

This invention relates to novel and improved catalyst and catalysts systems for the oligomerization of the higher olefins, which produce lubricants having improved properties, such as end-saturated oligomer chains which are needless to hydrogenation process, low kinematic viscosity and/or high viscosity index, low pour point, and high flash point lubricants.

This invention relates to novel and improved catalyst and catalysts systems for the oligomerization of the higher olefins, which produce lubricants having improved properties, such as end-saturated oligomer chains which are needless to hydrogenation process, low kinematic viscosity and/or high viscosity index, low pour point, and high flash point lubricants.

Provided are a lubricating oil composition used in a diesel engine equipped with a forced-induction compressor, containing a base oil (A) containing a poly-α-olefin (A1), and a viscosity index improver (B) having an SSI (shear stability index) of 20 or less, having a distillation amount of a light fraction of 496° C. or less in a gas chromatography distillation test of less than 80% by volume, having a high retention of the effect of suppressing the formation of deposits that may occur inside the compressor, and being capable of retaining a high efficiency of the compressor for a long period of time, in the use thereof in a diesel engine equipped with a forced-induction compressor having an outlet temperature of the compressor becoming a high temperature reaching 190° C. or more, and a method for using the lubricating oil composition.

The present invention provides a grease composition for electrical contacts, including: a thickener; a base oil; and an organic sulfur compound, wherein the organic sulfur compound is a compound having no heterocycle containing nitrogen in a molecule thereof.

The invention relates to a method of the oligomerization of C6 and above olefin monomer whereby, at a fixed monomer/Al halide mole ratio, polyalphaolefins having desirable kinematic viscosities are prepared by controlling the oligomerization temperature. The oligomerization is carried out in presence of an oligomerizing catalyst comprising of aluminum halide and a promoter, and oligomerizing temperatures of about 10° C. to about 120° C.

The invention relates to a method of the oligomerization of C6 and above olefin monomer whereby, at a fixed monomer/Al halide mole ratio, polyalphaolefins having desirable kinematic viscosities are prepared by controlling the oligomerization temperature. The oligomerization is carried out in presence of an oligomerizing catalyst comprising of aluminum halide and a promoter, and oligomerizing temperatures of about 10° C. to about 120° C.