摘要 |
The present invention relates to a metal compound of calixarene not containing sulfur and dispersible in oil, which can be partially salified, or neutral, or basic or overbased, said calixarene having general formula (I) in which: a) R1, R2, R3 and R4 are independently selected from hydrogen, or a group containing carbon and hydrogen, or a group containing in addition to carbon and hydrogen also heteroatoms, provided that said heteroatoms are not sulfur; b) one of the two substituents R5 and R6 is hydrogen, while the other may be selected from hydrogen, or a linear or branched alkyl with a number of carbon atoms between 1 and 6, preferably methyl, ethyl, 1 -propyl, 2-propyl, n-butyl, sec-butyl, more preferably methyl or ethyl; c) n is the number of units of the calixarene ring and is comprised in the range between 4 and 16, preferably between 5 and 12; said calixarene being characterized in that in at least one of the n units of the calixarene ring, at least one of the substituents R1, R2, R3 and R4 contains at least one acid group of carboxylic type available for the reaction with a metal base, with the proviso that said acid group of carboxylic type is not contained in a unit of the calixarene ring derived from salicylic acid. |