AEROSOL EMULSIONS AND FOAMS 629 Table II Effect of Method of Preparation upon the Properties of Triethanolamine Myristate/ Mineral Oil Emulsions Excess Triethanolamine System Cream- Method o{ Temp Range of ing Ag- Preparation Phase Composition a Order of of Droplet Time g]omer- (No.) Aqueous Oil Mixing Mixing Diameters (/•) (rain) ation * 1 H20,TEA Oil, MA Aq. to oil RT • 2--40 30--60 L 2 H20,TEA Oil, MA Aq. to oil 54.4øC • 2-40 15-30 M 3 H,O,TEA Oil,MA Oil to aq. RT • 2--50 5-15 H 4 H•O,TEA Oil,MA Oilto aq. 54.4 øC • 2-60 5-15 M 5 H•O,TEA,MA Oil Aq..to oil RT • 2-60 • 5 H 6 H20,TEA,MA Oil Oilto aq. 54.4øC • 2-65 • 5 H 7 H,oO,TEA, MA Oil Oil to aq. RT • 2--70 • 5 H 8 H•O,TEA,MA Oil Aq. to oil 54.4øC 2--70 • 5 H 9 • • 2--70 • 5 H 10 All mixed together 54.4øC •2-95 • 5 H 11 H20 Oil,TEA,MA Oi! to aq. RT 5--95 • 5 M 12 H20 Oi],TEA,MA Aq. to oil 54.4øC 5-150 • 5 H 13 H_oO Oil,TEA,MA Aq. to oil RT 5-170 • 5 H 14 H20 Oil,TEA,MA Oilto aq. 54.4øC 15--190 • 5 H aTEA = triethanolamine, MA -- myristic acid. •L ---- low, M = medium, H -- high. CPrep. No. 9 MA heated to 54.4øC TEA,H_•O heated to 54.4øC aq. phase added to MA at 54.4øC mixture cooled to RT oil added at RT. This simulates the preparation of an aerosol, Table III Best and Poorest Methods for Preparing Aqueous Triethanolamine Myristate/Mineral Oil Emulsions and Their Properties -Method of Phase Preparation Composition • TEA/MA (No.) Aqueous Oil Ratio I H. Oil Excess (Best) TEA MA MA 14 H•O Oil Excess (Poorest) TEA MA MA I H,O Oil Excess (Best) TEA MA TEA 14 H, Oil Excess (Poorest) MA TEA TEA Order Temp of Droplet Cream- of Aqueous Size ing Agglom- Mixing Phase (a) Time eration Aq. to Room 2-5 8-24hr Low oil temp Oil to 54.4 øC 2-35 3-16 hr Low aq. Aq. to Room 2-40 30-60 High oil temp min Oil to 54.4øC 15-190 5min ttigh aq. aTEA: triethanolamine, MA = myristie acid,

630 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Figure 1. Photomicrographs of the best and poorest aqueous triethanolamine myristate- mineral oil emulsions Top. Excess myristic acid. Left, best (procedure No. 1) right, poorest (procedure No. 14) Bottom. Excess triethanolamine. Left, best (procedure No. 1) right, poorest (procedure No. 14) Table IV Properties of Aqueous Triethanolamine Myristate/ Mineral Oil/Freon 12/Freon 114 (40/60) Emulsions and Foams Concentrate Properties Method of preparation TEA/MA ratio Oil droplet size (t•) Aerosol Properties Emulsion droplet size (t•) Emulsion stability and % phase separation Foam stability Stiffness (g) Wetting % drainage 15 min 30 min I 14 I 14 Excess Excess Excess Excess MA MA TEA TEA 2-5 2-35 2-40 15-190 2-40 2-40 2-80 (?) (?) 0% in 0% in 60--90 8 hrs 8 hrs rain 1.5% in 15% in 100% in 24 hrs 24 hrs 2.5 hrs 8 hrs 8 hrs 3.5-4 hrs 50 46 20 8hrs 8hrs lmin 2--120 100% in 15--30 rain lhr 18 i rain 0 0 6 83 0 0 48 78