Society of Cosmetic Chemists

JAMES P. BOWMAN, Hill Top Research Inc., P.O. Box 138, Miamiville, OH 45147; ALBERT M. KLIGMAN and TRACY STOUDEMAYER, S.K.I.N., Inc., 151 East Tenth Avenue, Conshohocken, PA 19428; and JOSEPH NICHOLSON, Product Investigations, 151 East Tenth Avenue, Conshohocken PA 19428.

Accepted for publication April 4, 2005.

Synopsis
A 10-day cumulative irritation test was conducted to evaluate whether or not test subjects 65 years of age and older would rank eleven test materials the same as subjects 18 to 45 years of age The test materials consisted of mild to moderately irritating chemicals. The test articles were ranked similarly for both groups of subjects. Statistical analysis indicated no significant difference between the groups of subjects. Thus older subjects should not necessarily be excluded in comparative studies of irritancy.

J. Cosmet. Sci., 56, 219–226 (July/August 2005)

Dissimilar effect of perming and bleaching treatments on cuticles: Advanced hair damage model based on elution and oxidation of S100A3 protein

KENJI KIZAWA, TAKAFUMI INOUE, MASAHITO YAMAGUCHI, PETER KLEINERT, HEINZ TROXLER, CLAUS W. HEIZMANN, and YOSHIMICHI IWAMOTO, Basic Research Laboratory (K.K., T.I.) and Cosmetics Laboratory (M.Y.), Kanebo Cosmetics Inc., 5-3-28 Kotobuki-cho, Odawara 250-0002, Japan; Department of Pediatrics, Division of Clinical Chemistry and Biochemistry, University of Zurich, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland (P.K., H.T., C.W.H.); and Beauty Care Laboratory, Kanebo Ltd., 134 Kanbe-cho, Hodogaya, Yokohama 240-0005, Japan (Y.I.).

Accepted for publication April 4, 2005. Presented in part at the 23rd Congress of the International Federation of the Societies of Cosmetic Chemists, Orlando, Florida, October 24–27, 2004.

Synopsis
Hair treatment chemicals induce sudden and severe hair damage. In this study, we examined cuticles from untreated, permed, and bleached hair that were mechanically discriminated by shaking in water. Both perming and bleaching treatments are prone to easily delaminate cuticles. Confocal microscopy revealed that the cuticles of permed hair were delaminated with larger pieces than untreated ones. On the other hand, the cuticles of bleached hair tend to fragment into small peptides. At the minimum concentration of thioglycolate required to elute S100A3 protein from the endocuticle into the reductive permanent waving lotion, enlarged delaminated cuticle fragments were observed. Although S100A3 is retained in bleached hair, S100A3 is irreversibly oxidized upon bleaching treatment. It is likely that the oxidative cleavage of disulfide bonds between cuticle-constituting proteins, including S100A3, results in the fragile property of cuticles. Here we present a more comprehensive model of hair damage based on a diverse mechanism of cuticle delamination.

J. Cosmet. Sci., 56, 227–251 (July/August 2005)

Hemp-seed and olive oils: Their stability against oxidation and use in O/W emulsions

S. SAPINO, M. E. CARLOTTI, E. PEIRA, and M. GALLARATE, Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, via Pietro Giuria No. 9, 10125 Turin, Italy.

Accepted for publication April 4, 2005.

Synopsis
Hemp-seed oil has several positive effects on the skin: thanks to its unsaturated fatty acid (PUFA) content it alleviates skin problems such as dryness and those related to the aging process. We present a comparative study of hemp-seed and olive oils, determining some physicochemical indices and evaluating their stability against oxidation. The peroxide value of hemp-seed oil was below 20, the threshold limit for edible oils. Hemp-seed oil was less stable against peroxidation than olive oil, but MDA and MONO assays showed its stability to be above expectations. The chlorophyll contained in extra virgin olive oil had a higher photostability than that contained in hemp-seed oil, possibly due to the larger amount of antioxidant in the olive oil. A certain amount of Vitamin E was found in hemp-seed oil. Since quality analyses indicated that hemp-seed oil is relatively stable, emulsions were prepared with the two oils, and their stability and rheological characteristics were tested. Some of the resulting gel–emulsions were suitable for spraying on the skin.

J. Cosmet. Sci., 56, 253–265 (July/August 2005)

Refractive index matching and clear emulsions

JAMES ZIMING SUN, MICHAEL C. E. ERICKSON, and JAMES W. PARR, Schwarzkopf and Henkel, 1063 McGaw Avenue, Suite 100, Irvine, CA 92614.

Accepted for publication April 4, 2005. Presented at the 2003 IFSCC Conference, Seoul, Korea, September 24, 2003.

Synopsis
Refractive index (RI) matching is a unique way of making clear emulsions to meet market trends. However, RI matching has not been sufficiently investigated in terms of physical principles and methodologies. Snell’s law (n2 sin r2 = n1 sin r1) is applicable to cosmetic emulsions. When oil phase and water phase have equal RI (n2 = n1) values, light will not bend as it strikes obliquely at the emulsion interface. Instead, light is transmitted through the emulsion without refraction, which produces clarity. Theoretical RI values in solution can be calculated with summation of the product of the weight percentage and refractive index of each ingredient (RImix = [W1 × n1 + W2 × n2 + W3 × n3 + ••• + Wn × nn]/WT). Oil-phase RI values are normally at 1.4 or higher. Glycols are used to adjust the water phase RI, since they typically have larger RI values than water. Noticeable deviations from calculated RI values are seen in experimentally prepared solutions. Three basic deviation types are observed: negative, positive, and slightly negative or positive, which can occur in glycol aqueous solutions at different concentrations. The deviations are attributed to changes in molecular interaction between molecules in solution, which can lead to changes in specific gravity. Negative RI deviation corresponds to a decrease in specific gravity, and positive RI deviation corresponds to an increase in specific gravity. RI values will deviate from calculated values since an increase or decrease in specific gravity leads to a change in optical density.

J. Cosmet. Sci., 56, 267–277 ( July/August 2005)

The influence of ascorbic acid on the rheological properties of the microemulsion region of the SDS/pentanol/water system

MARTA SZYMULA, Department of Radiochemistry & Colloid Chemistry, Faculty of Chemistry, Maria Curie Sklodowska University, M. Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland.

Accepted for publication April 4, 2005.

Synopsis
The rheological properties of the microemulsion region of the SDS, pentanol, and water micellar system have been studied experimentally. The W/O and O/W microemulsions behave as typical Newtonian fluids: viscosity remains constant independent of the shear rate. For the bicontinuous system the shear-thinning effect is observed. The addition of ascorbic acid to the system caused a microemulsion viscosity increase, which was the highest in the bicontinuous region and at the lowest temperature.

J. Cosmet. Sci., 56, 279–280 (July/August 2005)

Abstracts

International Journal of Cosmetic Science Vol. 27, No. 3, 2005*

J. Cosmet. Sci., 56, 281–282 (July/August 2005)

Abstracts

IFSCC Magazine Vol. 8, No. 2, 2005*