This disclosure relates to cold cranking simulator viscosity (CCSV) reducing base stocks that allow flexibility for low viscosity SAE engine oil grades (e.g., 5W and 0W) to meet demanding low temperature viscosity requirements while maintaining a higher base oil viscosity for improved wear protection. The CCSV-reducing base stocks include mono-esters derivable from a Guerbet alcohol and a monocarboxylic acid. The disclosure also relates to lubricating oils containing the CCSV-reducing base stocks, and a method for improving fuel efficiency and/or wear protection in an engine by using as the lubricating engine oil a formulated oil containing one or more of the CCSV-reducing base stocks.

This disclosure relates to cold cranking simulator viscosity (CCSV) reducing base stocks that allow flexibility for low viscosity SAE engine oil grades (e.g., 5W and 0W) to meet demanding low temperature viscosity requirements while maintaining a higher base oil viscosity for improved wear protection. The CCSV-reducing base stocks include mono-esters derivable from a Guerbet alcohol and a monocarboxylic acid. The disclosure also relates to lubricating oils containing the CCSV-reducing base stocks, and a method for improving fuel efficiency and/or wear protection in an engine by using as the lubricating engine oil a formulated oil containing one or more of the CCSV-reducing base stocks.

The present invention provides a lubricating oil composition comprising: (A) a lubricant base oil including at least one type selected from mineral oil, PAO, and GTL (gas-to-liquid) base oils; (B) a compound having a structure obtained by independently subjecting propylene oxide to addition polymerization with an alcohol or a structure obtained by subjecting a combination of propylene oxide with ethylene oxide and/or butylene oxide to addition polymerization with an alcohol, and being configured so that polyalkylene glycol (PAG) with an oxygen/carbon weight ratio of 0.35 or more and less than 0.45 and/or one or both terminal hydroxyl groups in the polyalkylene glycol (PAG) are blocked; and (C) a fatty acid ester having an oxygen/carbon weight ratio of 0.05 to 0.35.

The present invention provides a lubricating oil composition comprising: (A) a lubricant base oil including at least one type selected from mineral oil, PAO, and GTL (gas-to-liquid) base oils; (B) a compound having a structure obtained by independently subjecting propylene oxide to addition polymerization with an alcohol or a structure obtained by subjecting a combination of propylene oxide with ethylene oxide and/or butylene oxide to addition polymerization with an alcohol, and being configured so that polyalkylene glycol (PAG) with an oxygen/carbon weight ratio of 0.35 or more and less than 0.45 and/or one or both terminal hydroxyl groups in the polyalkylene glycol (PAG) are blocked; and (C) a fatty acid ester having an oxygen/carbon weight ratio of 0.05 to 0.35.

The present application relates to the use, in a lubricant composition comprising at least one base oil, of 2 to 12% by weight, relative to the weight of said lubricant composition, of an ester that has a viscosity at 100 C. of between 200 and 1000 cSt, for the purpose of improving the cleanliness of an engine.

The present application relates to the use, in a lubricant composition comprising at least one base oil, of 2 to 12% by weight, relative to the weight of said lubricant composition, of an ester that has a viscosity at 100 C. of between 200 and 1000 cSt, for the purpose of improving the cleanliness of an engine.

The present invention relates to a lubricant base oil containing an aromatic ester lubricant represented by Chemical Formula 1 and to a method for preparing the aromatic ester lubricant. By containing an aromatic ester lubricant, the lubricant base oil exhibits an excellent dispersibility and fluidity and is ecofriendly due to a high biodegradability. In addition, the method for preparing the aromatic ester lubricant does not generate such toxic substances as S, N, aromatic compounds and heavy metals and enables an easy control of the physical properties of a desired lubricant base oil by selecting a suitable alcohol compound to be introduced for an esterification reaction. ##STR00001##

The present invention relates to a lubricant base oil containing an aromatic ester lubricant represented by Chemical Formula 1 and to a method for preparing the aromatic ester lubricant. By containing an aromatic ester lubricant, the lubricant base oil exhibits an excellent dispersibility and fluidity and is ecofriendly due to a high biodegradability. In addition, the method for preparing the aromatic ester lubricant does not generate such toxic substances as S, N, aromatic compounds and heavy metals and enables an easy control of the physical properties of a desired lubricant base oil by selecting a suitable alcohol compound to be introduced for an esterification reaction. ##STR00001##

Disclosed is a lubricating oil composition capable of inhibiting vibrations or noises generated between a pulley and a chain or between a pulley and a belt in a CVT or the like, while increasing an intermetallic friction coefficient, the composition containing a base oil, an alkaline earth metal-based detergent (A), a phosphite ester (B1), a phosphate ester amine salt (B2), an acidic phosphate ester (B3), an aliphatic monoamine (C1), and an aromatic monoamine (C2).

Disclosed is a lubricating oil composition capable of inhibiting vibrations or noises generated between a pulley and a chain or between a pulley and a belt in a CVT or the like, while increasing an intermetallic friction coefficient, the composition containing a base oil, an alkaline earth metal-based detergent (A), a phosphite ester (B1), a phosphate ester amine salt (B2), an acidic phosphate ester (B3), an aliphatic monoamine (C1), and an aromatic monoamine (C2).