LUBRICANT COMPOSITIONS Russian patent published in 2023 - IPC C10M101/02 C10M171/00 C10M169/04 

FIELD: lubricants.

SUBSTANCE: invention relates to a lubricant composition intended for use as an oil for gas engines. Lubricating composition contains a base oil and one or more additives, and the composition has: the content of sulphated ash, when measured in accordance with ASTM D 874, at least 0.4 wt% and not more than 1.0 wt% based on the weight of the lubricant composition; a total base number (TBN) value, as measured in accordance with ASTM D 2896, of at least 4.0 mg KOH/g and not more than 12 mg KOH/g; the total content of aromatic hydrocarbons in the base oil in the range from 1 to 20 wt% based on the weight of the lubricant composition; and the sulphur content in the base oil of 0.4 wt% or less based on the weight of the lubricating composition. The base oil includes a mixture of (i) a first base oil, which is an API Group I mineral base oil, and (ii) a second base oil selected from an API Group II base oil and an API Group III base oil. Moreover, the mineral base oil of Group I according to API is present in an amount of from 5 to 40 wt% based on the weight of the lubricant composition and the lubricant composition contains an amine antioxidant containing an amine of formula (I)

and R² is hydrogen, an alkyl, aralkyl or alkaryl group, R³ is hydrogen, an alkyl or alkaryl group, with the proviso that when R² is hydrogen or an alkyl group of less than 8 carbon atoms, then R³ is an alkyl or alkaryl group containing at least 8 carbon atoms in the alkyl chain, and the amine antioxidant is present in an amount of from 1.5 to 3.0 wt% based on the weight of the lubricant composition. In addition, the invention relates to the use of a lubricating composition as a lubricating composition for a gas engine.

EFFECT: improving both the oxidation resistance and the cleaning index of lubricating compositions, especially compositions intended for use in a gas engine.

8 cl, 2 tbl, 13 ex