| abstract |
Lubricants which comprise, as an additive a salt of the reaction product ofn(i) glyoxylic acid or a hydrocarbyl substituted glyoxylic acid and (ii) anhydroxyaromatic compound, at least a portion of the molecules of which are alkylsubstituted,nare useful for lubricating ceramic-containing engines, high temperaturenengines, and natural gas-fueled engines. Particularly useful additives are those innwhich the hydroxyaromatic compound is a dialkyl phenol containing a t-butylngroup in an ortho position. |