PERMANENT WAVING 725 Table III Cystine Reduction Control-- Process Alkylated Per Cent Sample Half Cystinc '• Time Cysteine •' Reduction Acid wave (swatch) 15.5 per cent ( 1/2)t 2.1 •' 13.6 per cent Acid wave (swatch) 15.5 per cent t 3.0 •' 19.4 per cent Acid wave (swatch) 15.5 per cent 2t 4.0 •' 25.8 per cent Alkaline wave (swatch) 15.5 per cent (1/2)t 3.9 •' 25.2 per cent Alkaline wave (swatch) 15.5 per cent t 6.7 •' 43.2 per cent Alkaline wave (swatch) 15.5 per cent 2t 4.6 •' 29.7 per cent Acid wave (head) 15.0 per cent t 3.9 •' 26.0 per cent Acid wave (head) 16.1 per cent t 4.4 •' 27.4 per cent Acid wave (head) 15.7 per cent t 5.7 •' 36.1 per cent Alkaline wave (head) 15.0 per cent t 2.6 •' 17.3 per cent •*Moles/100 mol amino acids. •'SAE-cysteine. • CMT-cysteine. Table IV Stress-Strain Data--Acid Wave Average Force in Grams Average Per Cent Elongation Control 29.9 -+ 5.4 S.D. 39.6 -+ 1.2 S.D. After processing(1/2t% 12.3 -+ 2.1 S.D. 66.1 -+ 7.9 S.D. Afteroxidation(t) 18.3 -+ 6.1 S.D. 48.7 -+ 4.1 S.D. After oxidation (20 16.4 + 3.9 S.D. 47.2 -+ 4.7 S.D. •"'t" refers to processing time. Table V Acid Permanent Wave Hydrogen Peroxide Sodium Bromate Air Amino Acid Control (1/2)t t 2t (1/2)t t 2t 30' 24 H Lysine 2.4 2.5 2.3 2.4 2.4 2.3 2.5 2.5 2.5 Histidine 0.9 0.8 0.7 0.v 0.8 0.7 0.8 0.8 0.8 Arginine 6.6 6.6 6.1 6.2 6.6 8.2 7.0 6.6 5.8 Cysteic acid 0.4 0.5 0.4 0.6 0.6 0.7 0.9 0.4 CMT-CySH 1.4 1.3 1.6 1.3 1.7 1.2 0.5 1.1 Aspartic acid 5.5 5.4 5.4 5.3 5.3 5.1 5.6 5.5 5.4 Threonine 7.9 7.6 7.7 7.4 7.4 7.2 7.4 7.2 7.4 Serine 12.2 11.7 12.1 12.0 11.4 11.8 10.1 10.5 11.9 Glutamic acid 12.3 12.5 12.6 12.3 12.2 11.8 12.8 12.8 12.6 Proline 8.3 7.9 8.2 8.3 8.1 7.5 8.5 9.8 9.2 Glycine 6.1 6.5 6.3 6.4 6.4 6.5 6.5 8.0 7.7 Alanine 4.7 4.6 4.7 4.7 4.7 5.0 4.9 5.0 4.9 Half-cystine 15.5 12.9 13.3 13.2 13.3 13.1 11.0 10.4 12.1 Valine 5.1 5.7 5.9 5.8 5.9 5.9 6.2 6.2 5.9 Methionine 0.3 0.7 0.5 0.5 0.6 0.5 0.6 0.6 0.5 Isoleucine 2.3 2.7 2.6 2.7 2.9 2.6 3.2 2.9 2.3 Leucine 5.9 6.3 6.4 6.2 6.3 6.0 6.7 6.6 6.1 Tyrosine 2.1 2.1 2.0 2.1 2.0 1.9 2.0 2.2 2.1 Phenylalanine 1.6 1.6 1.6 1.7 1.6 1.6 1.7 1.7 1.6

726 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS decreased over 50 per cent to 12.3, whereas the percent elongation increased over 50 per cent to 66.1. Normally processed hair regains 61 per cent of the original grams force and the percent elongation has increased 23 per cent. In over processed hair, the strength has decreased to 55 per cent grams force and the elongation is about the same, 19 per cent high. Subsequent reoxidation, therefore, restores some of the original integrity of the fiber, but not all. Overprocessing of the hair (2t) results in more permanent damage. Tables V and VI show the amino acid data when oxidation variations were studied. Again, only cystine is significantly changed. The oxidation is not strong enough to cause significant oxidation of tyrosine as is seen in bleached hair. The cysteic acid formed during oxidation is seen to increase slightly with longer oxidation times, and in- dicates damage results from overneutralization. SEM documentation in our lab is consistent with this observation. No consistent differences are seen with hydrogen peroxide or sodium bromate in either acid or alkaline waves. However, in both cases, the air oxidation is not effective. Even after 24 hr, there is still free cysteine in the hair. Evidence for this is obtained by noting the proline content. Using sodium citrate buf- fers, cysteine elutes under the proline peak. This peak is high in all of the air oxidation samples. Table VII summarizes the cystine derivatives formed during permanent waving. Data on both swatches and salon treated hair involve permanent loss of cystine. This loss is accompanied by increases not only in cysteic acid during reoxidation, but also in the formation of CMT-CySH. There is some preliminary indication that CMT-CySH formation is greater under acidic conditions, but this remains to be established. The final cystine content is seldom equal to the original value even taking into account Table VI Alkaline Permanent Wave Hydrogen Peroxide Sodium Bromate Air Amino Acid Control (1/2)t t 2t (1/2)t t 2t 24 I-t Lysine 2.4 2.2 2.3 2.3 2.3 2.4 2.3 2.3 Histidine 0.9 0.8 0.8 0.8 0.8 0.9 0.8 0.7 Arginine 6.6 6.5 7.5 6.4 6.4 6.4 6.7 6.7 Cysteic acid 0.4 0.9 0.9 1.4 0.7 0.6 0.8 0.5 CMT-CySH + + 0.1 + 0.3 + + Aspartic acid 5.5 5.5 5.5 5.2 5.4 5.3 5.2 5.6 Threonine 7.9 7.6 7.7 7.4 7.5 7.5 7.6 7.7 Serine 12.2 11.2 11.9 11.5 11.6 11.7 12.0 11.1 Glutamic acid 12.3 12.6 12.6 12.2 12.3 12.2 12.5 12.8 Proline 8.3 8.0 8.4 8.5 8.3 7.9 8.0 9.1 Glycine 6.1 6.0 6.3 6.3 6.2 6.3 6.6 7.0 Alanine 4.7 4.6 4.7 4.5 4.5 4.6 4.9 4.7 Half-cystine 15.5 14.1 12.4 14.6 15.0 15.4 14.6 12.1 Valine 5.1 5.6 5.8 5.6 5.5 5.6 5.8 5.6 Methionine 0.3 0.5 0.4 0.6 0.6 0.5 0.5 0.7 Isoleucine 2.3 2.8 2.7 2.8 2.7 2.8 2.4 2.8 Leucine 5.9 6.4 6.3 6.2 6.3 6.2 6.2 6.5 Tyrosine 2.1 2.1 2.1 2.1 2.1 2.0 2.0 2.1 Phenylalanine 1.6 1.7 1.6 1.6 1.8 1.6 1.5 1.7