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.

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.

A refrigerating machine oil containing a hydrocarbon base oil having a 90% distillation temperature of 270° C. or lower.

Provided herein are olefinic feedstocks derived from conjugated hydrocarbon terpenes (e.g., C.sub.10-C.sub.50 terpenes), methods for making the same, and methods for their use.

Provided herein are olefinic feedstocks derived from conjugated hydrocarbon terpenes (e.g., C.sub.10-C.sub.50 terpenes), methods for making the same, and methods for their use.

The disclosure relates to a biobased metal-working fluid (MWF) composition and method for making same, and more particularly metal-working fluid with biobased lubricants with improved emulsion stability. At least 50 wt. % of the base oil component in the MWF concentrate is a plant-derived liquid decarboxylated rosin acid oil (“DCR”). The DCR comprises 50 to 100 wt. % of tricyclic compounds having 18-20 carbon atoms, one or more C═C groups, and m/z (mass/charge) value of 220-280; an oxygen content of <5%; a density of 0.9 to 1.0 g/cm.sup.3 at 20° C.; and an acid value of <10 mg KOH/g. The resulting MWF is characterized as having comparable if not better performance compared to a MWF containing only mineral oil (e.g., Group I or Group II).

The present invention relates to a process for preparing a residual base oil from a hydrocarbon feed which is derived from a Fischer-Tropsch process, the process comprises the steps of: (a) providing a hydrocarbon feed which is derived from a Fischer-Tropsch process; (b) subjecting the hydrocarbon feed of step (a) to a hydrocracking/hydroisomerisation step to obtain an at least partially isomerised product; (c) separating at least part of the at least partially isomerised product as obtained in step (b) into one or more lower boiling fractions and a hydrowax residue fraction; (d) catalytic dewaxing of the hydrowax residue fraction of step (c) to obtain a highly isomerised product; (e) separating the highly isomerised product of step (d) into one or more light fractions and a isomerised residual fraction; (f) mixing of the isomerised residual fraction of step (e) with a diluent to obtain a diluted isomerised residual fraction; (g) cooling the diluted isomerised residual fraction of step (f) to a temperature between 0° C. and −60° C.; (i) subjecting the mixture of step (g) to a centrifuging step at a temperature between 0° C. and −60° C. to isolate the wax from the diluted isomerised residual fraction; (j) separating the diluent from the diluted isomerised residual fraction to obtain a residual base oil.

The present invention relates to a process for preparing a residual base oil from a hydrocarbon feed which is derived from a Fischer-Tropsch process, the process comprises the steps of: (a) providing a hydrocarbon feed which is derived from a Fischer-Tropsch process; (b) subjecting the hydrocarbon feed of step (a) to a hydrocracking/hydroisomerisation step to obtain an at least partially isomerised product; (c) separating at least part of the at least partially isomerised product as obtained in step (b) into one or more lower boiling fractions and a hydrowax residue fraction; (d) catalytic dewaxing of the hydrowax residue fraction of step (c) to obtain a highly isomerised product; (e) separating the highly isomerised product of step (d) into one or more light fractions and a isomerised residual fraction; (f) mixing of the isomerised residual fraction of step (e) with a diluent to obtain a diluted isomerised residual fraction; (g) cooling the diluted isomerised residual fraction of step (f) to a temperature between 0° C. and −60° C.; (i) subjecting the mixture of step (g) to a centrifuging step at a temperature between 0° C. and −60° C. to isolate the wax from the diluted isomerised residual fraction; (j) separating the diluent from the diluted isomerised residual fraction to obtain a residual base oil.

A traction fluid comprising a blend of 2,3-dicyclohexyl-2,3-dimethylbutane (HAD) and 2,3-dicyclohexyl-2,3-dimethylbutane (iso-HAD) is found to have a lower viscosity at low temperatures when compared to a traction fluid having only HAD or only iso-HAD as a base fluid with no compromise to traction coefficient. The traction fluid may comprise additives. The traction fluid usually comprises HAD:isoHAD between about 8:1 to about 1:3. Further, the HAD:iso-HAD traction fluid blend is produced by a method of simultaneous co-production of hydrogenated HAD and hydrogenated iso-HAD from an alpha styrene dimer and an iso-HAD precursor with a yield of about 90% in a method that does not require a purification step.

A traction fluid comprising a blend of 2,3-dicyclohexyl-2,3-dimethylbutane (HAD) and 2,3-dicyclohexyl-2,3-dimethylbutane (iso-HAD) is found to have a lower viscosity at low temperatures when compared to a traction fluid having only HAD or only iso-HAD as a base fluid with no compromise to traction coefficient. The traction fluid may comprise additives. The traction fluid usually comprises HAD:isoHAD between about 8:1 to about 1:3. Further, the HAD:iso-HAD traction fluid blend is produced by a method of simultaneous co-production of hydrogenated HAD and hydrogenated iso-HAD from an alpha styrene dimer and an iso-HAD precursor with a yield of about 90% in a method that does not require a purification step.