METHOD FOR EVALUATION AND STUDY OF SHAMPOOS 223 A, CALCULATIONS very good precision when evaluating the relative deterRent efficiencies Control: of various surface-active agents. wt. of flask -5-) _ (wt. ofempty• contents flask ]= % grease content wt. of wool sample g. Scoured wool sample: grease content in• i/grease content in• control / -- •, scoured sample } grease content in control - % grease removal by deterRent DISCUSSION OF TEST METHOD All samples when run in duplicate gave a reproducibility as close as 0.3 per cent and a maximum of 2 per cent. Greater precision in all cases may be realized if the dupli- cate samples are shaken simultane- ously. An entire series may be scoured at one time by utilizing a suitable shaking apparatus with fairly slow rocker arms. This pro- cedure, however, would require re- moval of all wool samples at the same time to maintain uniform im- mersion in the deterRent solution. Based on the entire research pro- gram, the results would indicate TABLE 1--EvvECT OF CONCENTRATION OF SODIUM LAURYL SULFATE ON GREASE REMOVAL Concentration, 4-Minute 1-Minute % Scour, % Scour, % 0.005 0.010 0.015 0.020 0.025 0.035 0.040 0.050 0.10 0.t5 0.25 0.35 0.45 0.55 0.80 29.2 32.4 37.0 42.3 50.3 54 2 61 6 64 2 88 6 96 3 96 6 97 1 98.4 98.5 98.7 17.1 ß . . . 351o ß , 5516 8516 ß . ß . ß . When measuring the grease re- moval properties of competitive shampoos, the alkyl sulfate types invariably were more efficient, but in certain instances anomalous re- sults were obtained which indicate that a popular shampoo may not necessarily be a good deterRent. EVALUATION OF SURFACE-ACTIVE AGENTS (SURFACTANTS) ' A total of 43 compounds selected from deterRents, wetting agents, emulsifiers and solubilizers, of the anionic, non-ionic, and cationic types, were studied for their relative deterRent efficiencies in removing grease from raw wool yarn. In each case 0.5 gm. of compound was used, calculated on a 100 per cent basis, in a volume of 200 ml. (giving a 0.25 per cent solution), using the same scouring and rinsing proce- dure in all determinations. The alkyl sulfates were the most effective deterRents fatty acid soaps were generally lower in the scale a wetting agent was 10percent less effective than soap one non- ionic gave only 50 per cent grease removal, while another was one of the most effective deterRents while a branched-chain alkyl sulfate re-

224 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS TABLE 2•GREASE REMOVAL WITH 0.25% ACTIVE DETERGENT Grease Composition of Code Removed Detergent A 98.2 Sodium Alkyl Sulfate B 98.2 Sodium Alkyl Sulfoacetate C 98.2 Ammonium Alkyl Sulfate D 95.7 Polyglycol Alkyl Thioether E 95.0 Alkyl Amide Sulfonate F 94.4 Sodium Sulfoacetamide Fatty Ester G 93.3 Ammonium Sulfated Monoglyceride H 93.0 Alkylolamide Fatty Acid Condensate I 92.8 Sodium Sulfo Alkyl Fatty Ester J 92.6 Alkylolamide Fatty Acid Condensate K 92.3 Aromatic Polyglycol Ether L 92.2 Sodium Aralkyl Poly- glycol Ether Sulfate M 92.2 Alkyl Aryl Sodium Sul- fonate N 92.0 Alkylolamine Alkyl SuL fate O 90.3 Potassium Coconut Soap P 89.3 Alkyl Amide Sulfonate Q 88.4 Sodium Aralkyl Polygly- col Ether Sulfate R 84.8 Alkyl Aryl Sulfopropionic Ester S 84.3 Polyethylene Glycol Non-ionic T 81.7 Sodium Alkyl Aryl Poly- ether Sulfonate U 79.8 Sodium Dioctyl Sulfo- succinate V 77.9 Aromatic Polyglycol Ether W 77.0 ProteinrFattyAcid Amide Condensate X 73.7 Alkylolamine Aryl Sul- fonate Y 69.1 Alkylaryl Polyglycol Ether Z 63.5 Polyethylene Glycol Non-ionic AA 57.2 Polyglycol Fatty Ether BB 56.8 Alkyl Aryl Polyglyccl Ether CC 53.0 Polyoxyethylene Fatty Acid Ester DD 25.0 Sodium Alkyl Sulfate- Branched Chain EE 20.0 Sodium Alkyl Imidazol- inium Hydroxide FF --8.5 Acyl Pyridinium Chlo- ride GG --8 6 Benztrialkonium Chloride HH --9.4 Mcrpholinium Ethosul- fate II -12.7 Benztrialkonium Chlo- ride moved only one-quarter of the grease. With only 200 ml. of water and no detergent, 17 per cent of the grease is removed, presumably in- organic salts. Last in the grease removal scale are four cationic agents, all of which have negative results, indicating definite adsorp- tion of cationic ions by the wool. After scouring and extracting the cationic treated skeins, more mate- rial was obtained than is theoreti- cally possible based on grease con- tent, Table 2 and Graph III. In Graph I, five detergents are plotted as per cent grease removal versus per cent of detergent. The steepest slopes are obtained for the alkyl sulfate and alkyl phenol non- ionic compounds, while an alkyl aryl sulfonate and protein-fatty acid condensate show a more gradual TABLE 3--GREASE REMOVAL WITH 0.5% O•' COMMERCIAL SHAMPOOS Grease Type pH Extracted, Alkyl Sulfate 8.4 91.0 Alkyl Sulfate 9.2 93.0 Alkyl Sulfate 7.1 81.9 Alkyl Sulfate 7.6 81.0 Alkyl Sulfate 8.8 80.7 Miscellaneous 6.4 66.6 Alkyl Sulfate 7.7 61.7 Alkyl Sulfate 7.0 58.9 Alkyl Sulfate 7.8 58.7 Alkyl Sulfate 7.3 56.1 Alkyl Sulfate 7.3 41.4 Miscellaneous 6.6 39.1 Alkyl Sulfate 7.9 35.5 Soap 9.4 26.3 Soap 9.1 24.5 Soap 9.3 23.5 Soap 9.5 21.6 Soap 9.3 21.5 Miscellaneous 6.0 21.2 Water 17.0 Soap • i• --0.4 Soap 7.9 -0.5 Soap 6.6 -0.9 Soap 7.6 -0.8