288 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS FT-IR MEASUREMENTS Figure 5 shows the transmission spectra of the inside of the cortex for the untreated and DS-3 hair as measured by the FT-IR microscope. The larger peaks centered at 1650 --1 --1 --1 cm 1530 cm , and 1240 cm are Amide I, Amide II, and Amide III bands, respectively. There is no change between them, suggesting that the structure and chem- ical composition inside the cortex are not largely affected by KOH/1-butanol. Figure 6 shows the diffuse reflectance spectra from the assembly of the surface sections for the untreated DS-3 and DS-4 hairs. Appreciable changes in the spectrum are observed in the region from 1000 cm- 1 to 1100 cm- • Treatment with KOH/1-butanol may cause a . chemical change in several amino acid residues, particularly for cystine and cystein. The small band appeared at 1022 cm-• for DS-3 and at 1076 cm-• for DS-4. IR spectra of the oxidized wool and hair were reported (15-17), and the peaks at 1022 cm-t and at 1071 cm- 1 were assigned to S-sulfonate (Bunte salt) and the cystine monoxide band, respectively. 2 1.5 1800 I I 1600 Untreated DS-3 1400 1200 1000 Wavenumber (cm Figure 5. FT-IR spectra of inside hair (cortex) of untreated (--) and DS-3 ( .... ) hairs.

ISOLATION OF CUTICLE 289 0.25 0.2 0.15 0.1 Untreated DS-3 -- DS-4 0.05 :,,\ I v I ''\ t t ,' '\t: •, i • , ', , , \ 0 I 1800 1600 1400 1200 1000 Wavenumber (cm -1) Figure 6. Diffuse reflectance FT-IR spectra of the surface of untreated (--), DS-3 ( ...... ), and DS-4 (---) hairs. Arrows indicate the position of 1022 cm- • and 1076 cm- • peaks appearing in DS-3 and DS-4 hairs, respectively. Since the reaction mechanism in KOH/1-butanol is not completely understood as yet, the small peaks detected in DS-3 and DS-4 are not definitely characterized in the present work. We can conclude at least qualitatively that KOH/1-butanol solution penetrates only through the outer surface of the cortex and that the disulfide and SH groups are partly modified. They may be converted to cystein derivatives. The present work demonstrates that hair without cuticle cells can be obtained, provided that the treatment time in 5% KOH/1-butanol at 50øC is properly controlled. REFERENCES (1) P. H. Springell, Proteolysis of wool and its S-carboxymethyl derivatives by pronase and other pro- teases, A•st. J. Bid. $ci., 16, 727-755 (1965). (2) H. Hojo, Method for modifying wool fiber materials to advance quality grade thereof, U.S. Patent