US Patent 7314951 Process and composition for lower toxicity quaternary ammonium compounds

Betaine ester quaternary ammonium compounds with reduced toxicity and improved biodegradability are formed by esterification of a haloacetic acid with an alcohol containing at least 4 carbon atoms, followed by quaternization of the halo-acetate with a tertiary amine containing at least 4 carbon atoms. In one non-limiting embodiment the alkyl substituents on the nitrogen of the tertiary amine have at least 2 carbon atoms, and in another non-limiting embodiment are each n-butyl.