Abstract: Colloidal products are obtained by a process which comprises at least partial neutralization of an overbased colloidal bismuth sulphonate type product containing a basicity reserve in the form of micellized calcium, barium or magnesium carbonate, using at least one carboxylic acid containing sulphur and optionally containing nitrogen. These products can be used as antiwear and extreme-pressure additives in lubricating oils and greases.

Abstract: Colloidal products are described which comprise micelles of alkaline metals or alkaline-earth metals, held in the colloidal state by at least one alkaline metal or alkaline-earth metal alkyl- or alkylarylsulphonate. The products further comprise micelles of a product containing calcium, phosphorus and sulphur resulting from the in situ reaction of calcium oxide or calcium hydroxide with a phosphorus sulphide, in particular tetraphosphorus decasulphide, and water.These colloidal products are used as antiwear and extreme pressure additives for lubricating greases and oils.

Abstract: New sulfonated bismuth compounds and the preparation thereof are described. These new compounds can be represented by the following general formulae: ##STR1## where R.sub.1 represents a monovalent linear or branched aliphatic hydrocarbonaceous radical containing 8 to 36 atoms of carbon, and R.sub.2 represents an atom of hydrogen or a monovalent linear or branched aliphatic hydrocarbonaceous radical containing 8 to 36 atoms of carbon. These compounds, which possess surface-active and wear-fighting properties, are used as fuel additives. They can also serve as starting materials in the manufacture of overbased colloidal products usable as lubricant additives by carbonation of at least one calcium, barium, or magnesium oxide or hydroxide, the carbonate formed being kept as a colloidal dispersion in an organic medium by using at least one of the sulfonated bismuth compounds (I) and (II).

Abstract: Colloidal products according to the invention are obtained by a method comprising a step (a) providing a colloidal product containing at least one alkaline earth metal carbonate in micelle form, optionally reacted with at least one compound selected from alkylsulphonic acids and alkylarylsulphonic acids and salts thereof and long chain aliphatic carboxylic acids and salts thereof such as to modify a proportion of up to 70% of the basicity reserve of the original colloidal product and a step (b) in which the residual basicity reserve is neutralized by at least one acid containing at least one element selected from boron, phosphorus and sulphur. These colloidal products can be used as wear resistance and extreme pressure additives in lubricants.

Abstract: Colloidal products are described which contain an element selected from sulphur, phosphorus and possibly boron, as well as an element chosen from metal alkalis, alkaline earth metals and zinc, micellized in at least one detergent agent. They can be obtained in micelle form by reaction of at least one mineral acid or organic acid, containing sulphur and/or phosphorus and possibly an acid containing boron, these acids being directly introduced or formed in situ with at least one basic derivative containing a alkali metal and/or an alkaline earth metal and/or zinc, in the presence of at least one surface active agent. The colloidal products can be used as wear resistance and extreme pressure additives for lubricants.