Antimicrobial alcohol foam compositions and methods of preparation

1. A self-generated antimicrobial alcoholic foam prepared by combining:

an alcoholic pre-mix comprising:

at least 50 wt. % of a lower alcohol, based upon the total weight of the alcoholic pre-mix,

at least one acidic component comprising an organic acid selected from the group consisting of a sulfonic acid, an organophosphorous acid, a carboxylic acid, and mixtures thereof, and

at least one waxy component; and

an aqueous pre-mix comprising a carbonate.

2. The antimicrobial alcoholic foam of claim 1 , wherein the amount of acidic component is the stoichiometric amount of acid required to produce at least 0.02 moles of carbon dioxide per 100 g of combined aqueous pre-mix and alcoholic pre-mix.

3. The antimicrobial alcoholic foam of claim 1 , wherein the carbonate is selected from the group consisting of sodium carbonate, potassium carbonate, lithium carbonate, sodium bicarbonate, potassium bicarbonate, calcium bicarbonate, ammonium bicarbonate, and mixtures thereof.

4. The antimicrobial alcoholic foam of claim 1 , wherein the amount of carbonate is the stoichiometric amount of carbonate required to yield at least 0.02 moles of carbon dioxide per 100 g of combined aqueous pre-mix and alcoholic pre-mix.

5. The antimicrobial alcoholic foam of claim 1 , wherein the waxy component is selected from the group consisting of carnauba wax, ouricury wax, Japan wax, cork fiber wax, sugarcane wax, paraffin waxes, lignite waxes, microcrystalline waxes, lanolin wax, ozokerite, polyethylene wax, silicone waxes, plant waxes, C8-24 fatty alcohols, C8-24 fatty acids, glycerides that are solid at room temperature, blends of a C8-24 fatty alcohol with an ethoxylated C8-24 fatty alcohol, blends of a C8-24 fatty alcohol and a non-ionic surfactant, and mixtures thereof, with the proviso that the wax is at least sparingly soluble in a lower alcohol at standard temperature and pressure.

6. The antimicrobial alcoholic foam of claim 1 , wherein the waxy component is an emulsifying wax.

7. The antimicrobial alcoholic foam of claim 1 , wherein the waxy component is present in an amount of at least 0.1 wt. %, based upon the total weight of the combined alcoholic pre-mix and aqueous pre-mix.

8. The antimicrobial alcoholic foam of claim 1 , wherein one or both of the aqueous pre-mix and the alcoholic pre-mix further comprise an emulsifier selected from the group consisting of polysorbate, polaxamer, polyethoxylated siloxane polymer, or a mixture thereof.

9. The antimicrobial alcoholic foam of claim 1 , wherein the aqueous pre-mix may further comprise up to about 49 wt. % C 1-6 alcohol.

10. The antimicrobial alcoholic foam of claim 1 , wherein the foam expands upon the reaction of the acid and the carbonate to a final volume that is 1.5 to 5 times the combined liquid volume of the aqueous pre-mix and the alcoholic pre-mix.

11. The antimicrobial alcoholic foam of claim 1 , wherein the foam is stable for at least 1 minute at room temperature and pressure.

12. The antimicrobial alcoholic foam of claim 1 , where the acidic component comprises one or more carboxylic acids, selected from the group consisting of tartaric acid, malic acid, gluconic acid, fumaric acid, ascorbic acid, citric acid, isocitric acid, lactic acid, tartronic acid, oxalic acid, salicylic acid, malonic acid, and mixtures thereof.