SCANNING ELECTRON MICROSCOPIC TECHNIQUES 6•1 - . .. . -:..: . ... :.: . -. ?.• -•, -(,:/.•..:"*'• . :}'.•... •, ,--:•: :... -. \ ":'? ::•-, • •.•.. .... '-.%..,, . ½•.•..• .•¾ , -.: ..... • •.-•' '•. . •.. .... :•.• •.. . .... . ? :• • ß • '"' .. . .: ... Figure 11. Micrograph of same area as in Fig. 10 showing repair of shaft damage with one application of conditioner A closer look at the damage categories revealed that split ends account for 35% of all hair damage studies (Tables III and IV). Flyaway fibers and gen- eral shaft damage were found in 32 and 25% of the damaged sites, respective- ly. Table III Results of Shampoo Treatment Category Per Cent Damage Category Per Cent Improved Flyaway fibers 35 93 Exposed cortex 7 88 Split ends 35 60 Shaft damage 23 93

622 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table IV Results of Conditioner Treatment Category Per Cent Damage Category Per Cent Improved Flyaway fibers from cuticle 28 94 Exposed cortex 8 93 Split ends 35 95 General shaft damage 26 92 Miscellaneous 3 80 This study demonstrates improvement of all damage types after treatment. For example, based on a minimum reduction of one damage point in our rat- ing system, over 90% of the damaged site improved after treatment with the hair conditioning formulation. In fact, the conditioner actually dosed 60% of the split ends (improved to zero column). The shampoo formulation tested improved all types of hair damage (Table III). This study not .only demon- strates improvement of damage sites but reveals the products' ability to repair different types of damages. SU1VI•ARY A systematic approach to evaluate hair care products using the SEM has been developed. The technioue, employing a rot. ating hair stage (RHS) al- lows for maximum rotational freedom of the hair in the SEM. The hair, while still attached to the scalp, may be removed and re-introduced into the SEM as often as necessary. The difference ratio (DR), a numerical system showing the degree of change, revealed significant improvement of damaged sites after treatment with a hair conditioner and shampoo. ACKNOWLEDGMENT The author is grateful to Dr. C. Garber, President of Structure Probe Inc., for his continuing efforts and suggestions. All micrographs shown were taken at Structure Probe Inc. ( Received January 29, 1973) REFERENCES (1) Fraser, R. D. B., and Rogers, G. E., Aust. ]. Biol. Sci., 8, 129 (1955). (2) Barnes, R. B., Burton, C. J., and Scott, R. G., Electron microscopical replica technique for the study of organic surfaces, J. Appl. Phys., 16, 730 (1945). (3) Wolfram, J. L., and Lindemann, M. K. O., Some observations on the hair cuticle, ]. Soc. Cosmet. Chem., 22, 839 (1971). (4) Swift, J. A., New developments in electron microscopy, Ibid., 22, 477 (1971). (5) Ayer, P. A., and Thompson, J. A., Scanning electron microscopy and other new approaches to hair spray evaluation, Ibid., 23, 617 (1972).