PURPOSE: To obtain an overbased magnesium sulphonate useful for formation of sediment-free lubricating oil compositions by adding an ashless dispersant to a reaction mixture composed of the sulfonate or sulfonic acid in oil and an excessive magnesium compd. at the time of carbonating the reaction mixture in the presence of a hydrocarbon solvent and/or accelerator.
CONSTITUTION: An effective amt. of the ashless dispersant is further added to the reaction mixture for carbonation in the process for producing the overbased magnesium sulphonate by carbonating the reaction mixture which is composed of the sulfonate or sulfonic acid in the oil and the magnesium compd. and is optionally added with the hydrocarbon solvent and/or accelerator. The reaction mixture preferably contains the ashless dispersant of 0.5 to 10 wt.% of the formed overbased magnesium sulphonate. The reaction product of (a) hydrocarbyl substd. 4 to 10C monounsaturated acid or acid anhydride and (b) amine, alcohol, aminoalcohol or their mixture is preferably used as the ashless dispersant.
JIYON FUREDERITSUKU MAASHIYU
JIYOSEFU MARIAN SUUIITORITSUKU
