Non-petrochemically derived cationic emulsifiers and related compositions and methods
The invention includes a neutralized amino acid ester emulsifier, emulsions and compositions containing the emulsifier, and related methods. The emulsifier is a neutralized amino acid ester that is a reaction product of a neutral amino acid with a fatty alcohol and is represented by formula (I): wherein R 1 is an alkyl group that has 6 to 24 carbon atoms; R 2 is an alkyl group that has 6 to 36 carbon atoms; and the amine group of the amino acid is neutralized with an acid. The emulsifier is cationic. Also included are stable emulsions and compositions, preferably personal care compositions, that include the emulsifier and which may have pH levels of 5.5 or greater. Encompassed within the scope of the invention are methods of increasing the substantivity of a composition to a negatively charged substrate using the emulsifier, methods of emulsifying and methods of preparing a personal care composition using the emulsifier.
1. A method of increasing the substantivity of a composition to a negatively charged substrate comprising preparing a composition comprising at least one phase and an effective amount of an amino acid ester selected from the group consisting of octyldodecyl aminolaurate esylate, brassicyl aminolaurate esylate and isostearyl aminolaurate esylate that is a reaction product of a neutralized amino acid consisting of 12-aminolauric acid esterified with a fatty alcohol selected from the group consisting of octylododecyl alcohol, Brassica alcohol, and isostearyl alcohol, and applying the composition to a surface of hair, nails, or skin of a human, wherein the composition exhibits increased substantivity to a negatively charged surface relative to the substantivity of an identical composition that does not contain the amino acid ester and wherein the composition has a pH of 6.0 to 9.3.
2. The method of claim 1 , wherein the composition is an emulsion.
3. The method of claim 1 , wherein the neutral amino acid is obtained from vegetable matter.
4. A method of preparing an emulsified composition that exhibits substantivity when applied to a negatively charged substrate comprising combining an effective amount of an emulsifier, a first phase, and a second phase, wherein the emulsifier is an effective amount of an amino acid ester selected from the group consisting of octyldodecyl aminolaurate esylate, brassicyl aminolaurate esylate and isostearyl aminolaurate esylate that is a reaction product of a neutralized amino acid consisting of 12-aminolauric acid esterified with a fatty alcohol selected from the group consisting of octylododecyl alcohol, Brassica alcohol, and isostearyl alcohol; and the amine group of the amino acid is neutralized with an acid prior to esterification, wherein the emulsifier serves to emulsify the first and the second phases to form an emulsion.
5. The method of claim 4 , wherein the first phase is an aqueous phase and the second phase is a non-aqueous phase.
6. A method of emulsifying a personal care composition having an aqueous phase and a non-aqueous phase comprising incorporating the aqueous phase and a non-aqueous phase with each other in the presence of an effective amount of the emulsifier of claim 4 .
7. The method of claim 6 , wherein each of the aqueous phase and the nonaqueous phase is substantially free of petrochemicals and/or derivatives of petrochemical materials.
8. The method of claim 4 , wherein the emulsified composition has a pH of 6.0 to 9.3.