The present invention relates to a lubricating oil composition containing a mineral oil (A) containing 30% by mass or more of a bright stock (A1) on the basis of the total amount of the lubricating oil composition, wherein the lubricating oil composition further contains a synthetic oil (B) and a phosphoric acid ester (C), the content of the synthetic oil (B) is less than 70% by mass on the basis of the total amount of the lubricating oil composition, the content of the phosphoric acid ester (C) as expressed in terms of a phosphorus atom is 0.050 to 0.200% by mass on the basis of the total amount of the lubricating oil composition, and a viscosity index is 150 or more, thereby providing a lubricating oil composition having low temperature dependence and favorable lubricating characteristics even in the case of using the mineral oil containing a bright stock.

The present invention relates to a lubricating oil composition containing a mineral oil (A) containing 30% by mass or more of a bright stock (A1) on the basis of the total amount of the lubricating oil composition, wherein the lubricating oil composition further contains a synthetic oil (B) and a phosphoric acid ester (C), the content of the synthetic oil (B) is less than 70% by mass on the basis of the total amount of the lubricating oil composition, the content of the phosphoric acid ester (C) as expressed in terms of a phosphorus atom is 0.050 to 0.200% by mass on the basis of the total amount of the lubricating oil composition, and a viscosity index is 150 or more, thereby providing a lubricating oil composition having low temperature dependence and favorable lubricating characteristics even in the case of using the mineral oil containing a bright stock.

Disclosed herein is a process for preparing a sulfurized non-overbased calcium phenate detergent having a reduced content of un-sulfurized alkyl-substituted phenol and its salt. The process steps involve adding an organic solvent to the detergent, wherein the organic solvent has a boiling point of equal or above the boiling point of the un-sulfurized alkyl-substituted phenol. Distilling the organic solvent from the detergent to reduce the content of the un-sulfurized alkyl-substituted phenol.

The present invention discloses with the development of ecofriendly and biodegradable lubricant formulation useful for micro electro mechanical systems and process thereof. The new generation Mineral oil free lubricant formulations were developed by esterification of polyols such as 2,2-dimethyl, 1,3-Propanediol, 2,2-diethyl-1,3-propane diol, and aliphatic di carboxylic acids like adipic and azelaic and with mono alcohol, using heterogeneous catalyst Indion 140 with cation exchange properties. The said formulation has a viscosity in the range of 31 to 47 cSt at 40 C., a high viscosity index of 139-196, pour point of approximately <39 C. with a multifunctional EP additive of recommended dose of 1.5-4%. These new generation lubricants exhibited excellent biodegradability, a high viscosity index, and a low pour point, a high flash point, good lubricity, good oxidative stability, very good protection, against wear, no evaporation loss, good adherence to metal, corrosion inhibiting characteristics and suitability for use with commercial additives. In addition the products are non toxic to the sewage bacteria.

The present invention discloses with the development of ecofriendly and biodegradable lubricant formulation useful for micro electro mechanical systems and process thereof. The new generation Mineral oil free lubricant formulations were developed by esterification of polyols such as 2,2-dimethyl, 1,3-Propanediol, 2,2-diethyl-1,3-propane diol, and aliphatic di carboxylic acids like adipic and azelaic and with mono alcohol, using heterogeneous catalyst Indion 140 with cation exchange properties. The said formulation has a viscosity in the range of 31 to 47 cSt at 40 C., a high viscosity index of 139-196, pour point of approximately <39 C. with a multifunctional EP additive of recommended dose of 1.5-4%. These new generation lubricants exhibited excellent biodegradability, a high viscosity index, and a low pour point, a high flash point, good lubricity, good oxidative stability, very good protection, against wear, no evaporation loss, good adherence to metal, corrosion inhibiting characteristics and suitability for use with commercial additives. In addition the products are non toxic to the sewage bacteria.

A lubricating composition includes a sulfurized oxy-substituted aromatic polyol compound and an oil of lubricating viscosity. The sulfurized oxy-substituted aromatic polyol compound includes at least one of a sulfurized oxy-substituted aromatic polyol and a salt of a sulfurized oxy-substituted aromatic polyol. The compound is suitable as a replacement for detergents that contain C.sub.n alkyl phenols derived from oligomers of propylene.

Disclosed herein is a method of using a water-based coolant for quenching or cutting a metal material. The water-based coolant is formed of: water; at least one inorganic acid salt selected from the group consisting of a carbonate, a hydrogen carbonate, a sesquicarbonate, a phosphate, a borate, a molybdate and a tungstate; a metal corrosion inhibitor; and optionally at least one of a bactericide, a water-soluble rust inhibitor, an antioxidant and a detergent dispersant.

Disclosed herein is a method of using a water-based coolant for quenching or cutting a metal material. The water-based coolant is formed of: water; at least one inorganic acid salt selected from the group consisting of a carbonate, a hydrogen carbonate, a sesquicarbonate, a phosphate, a borate, a molybdate and a tungstate; a metal corrosion inhibitor; and optionally at least one of a bactericide, a water-soluble rust inhibitor, an antioxidant and a detergent dispersant.

A lubricating composition includes an oil of lubricating viscosity and an N-substituted hydroxyaromatic succinimide or a salt thereof.

A lubricating composition includes an oil of lubricating viscosity and an N-substituted hydroxyaromatic succinimide or a salt thereof.