138 JOURNAL OF COSMETIC SCIENCE The carboxy silicone fatty quat complexes are: Fatty quats Silicone complexes 1. Cetyltrimonium chloride 3. Stearalkonium chloride 2. Cetrimonium dimethicone copolyol phthalate 4. Stearalkonium chloride copolyol phthalate EYE IRRITATION Primary eye irritation was tested using the protocol outlined in FHSLA 16 CFR 1500.42. The products were tested at 25% actives in water. The results were as follows: 1. Cetyltrimonium chloride 2. Silicone complex of cetyltrimonium chloride 3. Stearalkonium chloride 4. Silicone complex of stearalkonium chloride 106.0 Severely irritating 8.3 Minimally irritating 116.5 Severely irritating 11.3 Minimally irritating At a concentration of 0.5%, stearalkonium chloride was minimally irritating. This rating was the same as those of silicone complexes at 25% (or 50 times the concentra- tion). As the data clearly shows, the irritation potential of the complex is dramatically reduced when compared to the starting quat. SILICONE PHOSPHATES WITH SLS We have also recently learned that dimethicone copolyol phosphate is effective as a counterirritant of skin irritation when combined with sodium lauryl sulfate. Dimethi- cone copolyol phosphate is a new silicone surfactant that has been the topic of several patents in recent months (3,4). The primary skin irritation data presented was run using FHSLA 16 CFR 1500.41. We investigated skin irritation using the following data: Example 1 Material % Solids Sodium lauryl sulfate 5.0 Example 2 Material % Solids Sodium lauryl sulfate 5.0 Dimethicone copolyol phosphate 1.0 Skin irritation was reduced from a score of 2.25 (moderately irritating) for example 1 to 1.17 (mildly irritating) for example 2.

LETTER TO THE EDITOR 139 We applaud the work and its implications to the formulation of low-irritation products. Anthony J. O'Lenick, Jr. Lambent Technologies Inc. Norcross, GA 30093 REFERENCES (1) U.S. Patent 5,296,434, issued March 1994. (2) U.S. Patent 5,248,783, issued September 1993. (3) U.S. Patent 5,093,452, issued March 1992. (4) U.S. Patent 5,149,765, issued September 1992.