The disclosure relates to viscosity improver concentrates comprising a bio-based liquid decarboxylated rosin acid as a solubilizer, and a viscosity index improver. The viscosity improver concentrate is used in lubricating oil compositions comprising base oil and optional additives. The decarboxylated rosin acid component has at least one or more of: one or more C?C groups, and 40-100 wt. % of tricyclic compounds having 18-20 carbon atoms; a sum of tricyclic compounds as aromatic and cycloaliphatic of 50-100 wt. %, based on total weight of the decarboxylated rosin acid; and an amount of cycloaliphatic compounds of 15-100 wt. %, based on total weight of the decarboxylated rosin acid. The viscosity improver concentrates comprising the solubilizer have comparable properties, including compatibility, kinematic viscosity, and viscosity index, to other commonly used fossil based solubilizers.

The disclosure relates to viscosity improver concentrates comprising a bio-based liquid decarboxylated rosin acid as a solubilizer, and a viscosity index improver. The viscosity improver concentrate is used in lubricating oil compositions comprising base oil and optional additives. The decarboxylated rosin acid component has at least one or more of: one or more C?C groups, and 40-100 wt. % of tricyclic compounds having 18-20 carbon atoms; a sum of tricyclic compounds as aromatic and cycloaliphatic of 50-100 wt. %, based on total weight of the decarboxylated rosin acid; and an amount of cycloaliphatic compounds of 15-100 wt. %, based on total weight of the decarboxylated rosin acid. The viscosity improver concentrates comprising the solubilizer have comparable properties, including compatibility, kinematic viscosity, and viscosity index, to other commonly used fossil based solubilizers.

The present invention relates to a steel cord for rubber reinforcement. In the steel cord of the present invention, cobalt is contained by 0.001 ppm to 0.1 ppm within a 4 nm top-surface of the brass-plated steel wire. A method of manufacturing the steel cord includes: providing a brass-plated steel wire; mixing a cobalt compound in a wet lubricant filled in a wet drawing bath provided with a plurality of drawing dies between one pair of multi-stage drawing cones such that the concentration of the cobalt compound becomes 0.1 ppm to 100 ppm; and causing the cobalt to be contained by 0.001 ppm to 0.1 ppm within a 4 nm top-surface of the brass-plated steel wire after the brass-plated steel wire passes through a final die by causing the cobalt to be attached to a surface of the brass-plated steel wire and alloyed with a brass layer while the brass-plated steel wire is passing through the drawing cones and the drawing dies to be subjected to multi-stage drawing.

The present invention relates to a steel cord for rubber reinforcement. In the steel cord of the present invention, cobalt is contained by 0.001 ppm to 0.1 ppm within a 4 nm top-surface of the brass-plated steel wire. A method of manufacturing the steel cord includes: providing a brass-plated steel wire; mixing a cobalt compound in a wet lubricant filled in a wet drawing bath provided with a plurality of drawing dies between one pair of multi-stage drawing cones such that the concentration of the cobalt compound becomes 0.1 ppm to 100 ppm; and causing the cobalt to be contained by 0.001 ppm to 0.1 ppm within a 4 nm top-surface of the brass-plated steel wire after the brass-plated steel wire passes through a final die by causing the cobalt to be attached to a surface of the brass-plated steel wire and alloyed with a brass layer while the brass-plated steel wire is passing through the drawing cones and the drawing dies to be subjected to multi-stage drawing.

The disclosure relates to viscosity improver concentrates comprising a bio-based liquid decarboxylated rosin acid as a solubilizer, and a viscosity index improver. The viscosity improver concentrate is used in lubricating oil compositions comprising base oil and optional additives. The decarboxylated rosin acid component has at least one or more of: one or more CC groups, and 40-100 wt. % of tricyclic compounds having 18-20 carbon atoms; a sum of tricyclic compounds as aromatic and cycloaliphatic of 50-100 wt. %, based on total weight of the decarboxylated rosin acid; and an amount of cycloaliphatic compounds of 15-100 wt. %, based on total weight of the decarboxylated rosin acid. The viscosity improver concentrates comprising the solubilizer have comparable properties, including compatibility, kinematic viscosity, and viscosity index, to other commonly used fossil based solubilizers.

The disclosure relates to viscosity improver concentrates comprising a bio-based liquid decarboxylated rosin acid as a solubilizer, and a viscosity index improver. The viscosity improver concentrate is used in lubricating oil compositions comprising base oil and optional additives. The decarboxylated rosin acid component has at least one or more of: one or more CC groups, and 40-100 wt. % of tricyclic compounds having 18-20 carbon atoms; a sum of tricyclic compounds as aromatic and cycloaliphatic of 50-100 wt. %, based on total weight of the decarboxylated rosin acid; and an amount of cycloaliphatic compounds of 15-100 wt. %, based on total weight of the decarboxylated rosin acid. The viscosity improver concentrates comprising the solubilizer have comparable properties, including compatibility, kinematic viscosity, and viscosity index, to other commonly used fossil based solubilizers.