2007 ANNUAL SCIENTIFIC SEMINAR 585 a e . T bl I S torage, oss an dY d I oung s mo u us DMA Tensile Storage Loss Tanp Young's RH Modulus, E" Modulus, E' (E"/E') Modulus (E) (MPa) (MPa) 40 4978.3 121.3 0.0243 6.6E+09 Asian 60 4454.7 137.8 0.0310 5.4E+09 80 3676.7 143.0 0.0388 4.7E+09 40 5239.6 108.6 0.0207 l.IE+IO Caucasian 60 4792.0 129.2 0.0272 8.7E+09 80 4150.2 138.6 0.0336 7.6E+09 Bleached 40 5808.4 115.4 0.0198 8.3E+09 60 5208.1 141.9 0.0271 7.5E+09 15mins 80 4331.6 160.1 0.0372 7.0E+09 Bleached 40 5781.7 127.9 0.0223 8.8E+09 60 5107.1 151.0 0.0297 9.IE+09 30mins 80 4130.7 155.7 0.0378 8.4E+09 It is observed that Asian hair showed lower storage and Young's modulus but higher values of loss modulus compared to Caucasian hair. This implies that Asian hair is less elastic and more viscous. Asian hair also shows higher damping property, tan 8 (E" / E'), indicating a greater energy lost during deformation. Experimental results indicated that hair elasticity decreased and hair damping increased with an increase in bleaching time. The bleaching process reduces the crosslink density of the matrix, thus decreasing the efficiency of molecular rearrangements which, in turn, causes the higher damping property and reduction in the elasticity. Increasing humidity levels shows significant effects on reducing hair stiffness and increasing viscous property. Changes in loss modulus and Tan o of Caucasian hair with humidity before and after cosmetic treatments are shown in Figure I. After a conditioning shampoo treatment, the average loss modulus and damping of Caucasian hair fibers are decreased. This indicated that the hair became less viscous and more elastic after the treatment. Therefore, the treatment improved hair strength. 0.0400 0.0350 0.0300 0.0250 0.0200 0.0150 0.0100 0.0050 0.0000 30 Figure I. Effect of cosmetic treatment on Caucasian hair · ·········································•··••·············........................, 160.0 ,.. .............................................................................................. , --Caucasian-untreated N � N Caucasian-treated wth Incroquat 1266 40 50 60 Hmidity,% 70 80 90 .. - j 80.0 60.0 40.0 20.0 0.0 30 40 • • • Caucasian-treated with Incroquat 1266 50 60 Humidity,% 70 80 90 1 Kevin P. Menard, Dynamic mechanic analysis: a practical introduction, 1999.

586 JOURNAL OF COSMETIC SCIENCE INFRARED MICRO-SPECTROSCOPIC IMAGING OF CHANGES IN NATURAL MOISTURIZING f AClOR (NMF) IN HUMAN STRATUM CORNEUM David J. Moore, Ph.D. International Specialty Products, Global R&D, Wayne, NJ, USA Introduction Recent advances in infrared (IR) spectroscopic imaging and confocal Raman micro-spectroscopy have permitted the acquisition of spatially resolved chemical composition and structural information from biologically important samples [1,2). Challenges in data collection and interpretation are being confronted and SUIInOunted as the work. moves from serving as an adjunct to histopathology to playing a more predictive role in diagnosing disease, providing insights into the molecular interactions preceding the onset of disease, and tracking the effectiveness of therapeutics on a molecular level. In the current study, the maturation process of individual human Optical and lnl'rared lma&lng or hmnan comeocyta. Representative IR 1pectn or comeocytn Isolated 1n,m the 11th (bottom spedrum) md 3rd (top spectrum) tape strips. comeocytes obtained from different depths in the SC was investigated using IR micro--spectroscopic imaging. Instrumental details and experimental methods have been described [ 4,5). The results from experiments conducted on cells isolated from healthy skin reveal depth dependent compositional differences and provide an initial baseline from which an examination of the variability between subjects, body sites, age, and a variety of disease states can be made. Our recent studies indicate that changes in NMF levels induced by skin cleansing can be directly detected via IR micro­ spectroscopic imaging of corneocyles from washed versus control sites at the same depth within the stratum comeum. Materials and Methods Corneocytes from different SC layers were collected from human foreann skin by sequential tape stripping. The first two tape strips were discarded and comeocytes collected from the third, sixth, and eleventh tape strips. IR microscopic images were acquin:d with the Perk.in-Ebner Spotlight system consisting of an essentially linear array (16 x I detector elements) mercury­ cadmiwn-telluride (Men. About SO comeocytes from each layer were randomly selected and IR images (60 x 60 microns) were acquired with a pixel size of 6.2S microns. Each comeocyte image was acquin:d in approximately 20 minutes. ISys 3.0 software (Spectral Dimensions, Maryland) was used for analysis and construction of the IR images. Linear baselines were applied A I•··:_ - /\ 1� � --v � \ Jij/ "'-.__/_\... .� I N� - '- UH UH 1111 UH HH � Wavenumberlem "' Mean Infrared lm1111Dg spectn of multiple comeocytes from two depths In human SC compared to IR spectnim or model NMF mm. over spectral regions of interest Data interpretation was facilitated by averaging the spectra of comeocytes from particular stratwn comewn layers to improve signal to noise ratios. Correlation coefficients were then calculated between the mean spectrum of each layer and each spectrwn contained in an image to generate correlation maps.