a novel imidazolinium salt is prepared by reacting n - aminoalkyl - imidazoline , n - hydroxyalkyl - imidazoline , or n - substituted - imidazoline with an α , β - unsaturated ester of a carboxylic acid , reacting the resulting ester imidazoline with a primary or secondary amine and quaternizing the resulting amido imidazoline product by reacting it with an alkylating agent . this imidazolinium salt is useful as a fabric softening agent .