Lubricating oil additive composition and lubricating oil composition

A method of producing a lubricating oil composition, the method comprising:

• a) adding and mixing (i) a Broensted acid salt of at least one first amide compound to and with a lubricant base oil, or to and with a mixture containing the lubricant base oil and at least one additive other than the (i) component, the Broensted acid salt being a salt of the first amide compound and a Broensted acid, the first amide compound being a monoamide of at least one C6-30 linear or branched chain saturated or unsaturated monovalent fatty acid (a1), and at least one amine compound (a2), the monoamide having no ester bond, the amine compound (a2) being an alkanolamine oligomer having a structure such that at least one alkanolamine (a3) represented by the following general formula (1) is subjected to dehydration condensation, the alkanolamine oligomer having a degree of polymerization of no less than 2, wherein
• the lubricant base oil includes at least one mineral base oil, at least one synthetic base oil, or a combination thereof, and
• the Broensted acid includes at least one inorganic acid selected from halogenated hydrogen, nitric acid, boric acid, and carbonic acid, or at least one organic acid selected from a carboxylic acid, and a substituted or unsubstituted phenol, or a combination thereof:
• in the general formula (1), n is 1 or 2;
• R1 is C1-4 linear chain alkylene or C3-10 branched chain alkylene, the C3-10 branched chain alkylene having a main chain, the main chain having a carbon number of 2;
• and when n is 2, a plurality of R1's may be the same, and may be different from each other.

A lubricating oil additive composition comprising:

• (i) a Broensted acid salt of at least one first amide compound, the Broensted acid salt being a salt of the first amide compound and a Broensted acid, the first amide compound being a monoamide of at least one C6-30 linear or branched chain saturated or unsaturated monovalent fatty acid (a1), and at least one amine compound (a2), the monoamide having no ester bond, the amine compound (a2) being an alkanolamine oligomer having a structure such that at least one alkanolamine (a3) represented by the following general formula (1) is subjected to dehydration condensation, the alkanolamine oligomer having a degree of polymerization of no less than 2, wherein
• the Broensted acid includes at least one selected from lauric acid, oleic acid, hydrochloric acid, boric acid, and 2-decyltetradecanoic acid, or a combination thereof:
• in the general formula (1), n is 1 or 2;
• R1 is C1-4 linear chain alkylene or C3-10 branched chain alkylene, the C3-10 branched chain alkylene having a main chain, the main chain having a carbon number of 2;
• and when n is 2, a plurality of R1's may be the same, and may be different from each other.