Patent ID: 8414906

Claim:
An oligoester comprising at least two structural units, each structural unit having a diol fragment containing a quaternary nitrogen atom and a diacid fragment attached to one another by an ester linkage, said structural units defining a backbone extending through said ester linkages and said quaternary nitrogen atoms, wherein at least one of said diol fragment comprises a propoxy group which is bound between said diol fragment and at least one of said diacid fragments, wherein at least some of said diacid fragments are structurally different, wherein at least one of the diacid fragments is derived from C36 dimer acid, wherein at least another of said diacid fragments is selected from the group consisting of adipic acid, azeliec acid, malonic acid, pimelic acid, sebacic acid, suberic acid, and succinic acid, and wherein the diol fragment is derived from an amine diol, and wherein the amine diol is selected from the group consisting of N-ethyl-N, N-diethanol, N-methyl-N, N-dimethanol, methyl diethanolamine, benzyl diethanolamine, lauryl diethanolamine, cetyl diethanolamine, stearyl diethanolamine, erucyl diethanolamine and behenyl diethanolamine.