[Technical Problem] An object is to provide a lubricant capable of forming a stable adsorption film on a sliding surface and stabilizing the sliding characteristics (for example, ensuring the wear resistance, etc.). [Solution to Problem] The present invention provides a lubricant represented by the following chemical structural formula. ##STR00001## (R: a hydrocarbon group whose carbon number is 8 to 24, m and n: integers of 2 to 8) [Selected Figure] FIG. 5A

Systems and methods are provided for producing lubricant basestocks having a reduced or minimized aromatics content. A first processing stage can perform an initial amount of hydrotreating and/or hydrocracking. A first separation stage can then be used to remove fuels boiling range (and lower boiling range) compounds. The remaining lubricant boiling range fraction can then be exposed under hydrocracking conditions to a USY catalyst including a supported noble metal, such as Pt and/or Pd. The USY catalyst can have a desirable combination of catalyst properties, such as a unit cell size of 24.30 or less (or 24.24 or less), a silica to alumina ratio of at least 50 (or at least 80), and an alpha value of 20 or less (or 10 or less). In some aspects, the effluent from the second (hydrocracking) stage can be dewaxed without further separation. In such aspects, a portion of the dewaxed effluent can be used as a recycle quench stream to cool the hydrocracking effluent prior to entering the dewaxing reactor.

Disclosed are Group III base stocks comprising greater than or equal to about 90 wt. % saturated hydrocarbons (saturates); a viscosity index from 120 to 145; a unique ratio of molecules with multi-ring naphthenes to single ring naphthenes (2R+N/1RN); a unique ratio of branched carbons to straight chain carbons (BC/SC); a unique ratio of branched carbons to terminal carbons (BC/TC); and unique MRV behavior as a function of base stock naphthene ratio (2R+N/1RN). A method for preparing the base stocks is also disclosed. Also disclosed is a lubricating oil having the base stock as a major component, and an additive as a minor component.

A base stock having at least 90 wt. % saturates, an amount and distribution of aromatics, as determined by ultra violet (UV) spectroscopy, including an absorptivity between 280 and 320 nm of less than 0.015 l/gm-cm, a viscosity index (VI) from 80 to 120, and having a cycloparaffin performance ratio greater than 1.05 and a kinematic viscosity at 100 C. between 4 and 6 cSt. A base stock having at least 90 wt. % saturates, an amount and distribution of aromatics, as determined by UV spectroscopy, including an absorptivity between 280 and 320 nm of less than 0.020 l/gm-cm, a viscosity index (VI) from 80 to 120, and having a cycloparaffin performance ratio greater than 1.05 and a kinematic viscosity at 100 C. between 10 and 14 cSt. A lubricating oil having the base stock as a major component, and one or more additives as a minor component. Methods for improving oxidation performance and low temperature performance of formulated lubricant compositions through the compositionally advantaged base stock.

Disclosed herein is a mineral base oil satisfying the following requirements (I) to (V): (I): a kinematic viscosity at 100 C. is 2 mm.sup.2/s or more and less than 7 mm.sup.2/s; (II): a viscosity index is 100 or more; (III): a temperature gradient |*| of complex viscosity between two points of 10 C. and 25 C. is 60 Pa.Math.s/ C. or less as measured with a rotary rheometer under conditions at an angular velocity of 6.3 rad/s and a strain amount of 0.1 to 100%; (IV): a content ratio [R1/R2] of a monocyclo paraffin component (R1) to a dicyclo to hexacyclo paraffin component (R2) is 0.70 or less by a volume ratio as measured in accordance with ASTM D2786; and (V): a % C.sub.A is less than 1.0.

The invention is a fluid having a kinematic viscosity from 3 to 6 mm.sup.2/s, a flash point of higher than 120? C. and a pour point lower than ?40? C., having a boiling point in the range of from 200? C. to 400? C. and a boiling range below 80? C., said fluid comprising more than 95% isoparaffins and less than 3% of naphthens by weight, a biocarbon content of at least 95% by weight, containing less than 100 ppm aromatics by weight. The invention is also a drilling fluid and the use of the fluid to improve the viscosity of the drilling fluid.

A low viscosity oil has more than 50% by weight of 9-methylnonadecane. A lubricating composition has this low viscosity oil as base oil and, optionally, another base oil or an additive. The low viscosity oil has a kinematic viscosity at 100 C., measured by the ASTM D445 standard, of 0.5 to 2.5 mm.sup.2s.sup.1. The low viscosity oil can be prepared using a metallocene catalyst, and the low viscosity oil can be used as high performance lubricant for lubrication in the field of motors, hydraulic fluids and gears, in particular bridges and transmissions.

The present application relates to citric acid-modified polypropylene glycols which are represented by Formula (1) or, as well as compositions comprising such compounds. The polypropylene glycol-based compounds of the invention are useful as additives and in particular as emulsifying agents in e.g. cooling lubricants, as release agents, as well as additives for cosmetic products.

A comb polymer can be used for reducing a Noack evaporation loss of a lubricant composition, especially of an engine oil composition. Application of the comb polymer to the lubricant composition can bring about the desired reduction. The comb polymer can include specified amounts of macromonomer and alkyl acrylates. Resulting lubricant compositions can include the comb polymer.

Disclosed are Group III base stocks comprising greater than or equal to about 90 wt. % saturated hydrocarbons (saturates); a viscosity index from 120 to 145; a unique ratio of molecules with multi-ring naphthenes to single ring naphthenes (2R+N/1RN); a unique ratio of branched carbons to straight chain carbons (BC/SC); a unique ratio of branched carbons to terminal carbons (BC/TC); and unique MRV behavior as a function of base stock naphthene ratio (2R+N/1RN). A method for preparing the base stocks is also disclosed. Also disclosed is a lubricating oil having the base stock as a major component, and an additive as a minor component.