632 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table II Surfactants Giving Improved Coatability Resin PVP/VA copolymer Resin D Resin R-1 _ Atlas Chenficals Division, ICI America, Wilmington, Del. Nonionic Surfactants • Atmul 651K Arlacel 85 Atmos 300 Arlacel 85 Atmul 651K Atpet 100 Renex 35 G-1096 Renex 35 Table III Concentrate Optimization for Resin R-2 Formulation Two-level factoriM design (25) Additives: Oleyl alcohol AMPD a Perfume Isopropyl myristate Acetulan b Other Components: Resin P,-2 Freon 12/Freon 11 (50/50) propellant Denatured anhydrous ethanol Commercial Solvents Corp., New York, N.Y. Amercho1, a Unit of CPC International, Inc., Edison, N, J. Per Cent 0 and 0.4 0 and 0.2 0 and 0.5 0 and 0.4 0 and 0.4 1.5 60.0 Remainder and the results are described using carboxylated vinyl acetate terpolymer (Resin R-2) as an example (Table III). The same technique was used for a polyacrylic (Resin D) and a partially ester/fled methyl vinyl ether/ maleic acid copolymer (Resin G-2). Five common additives, chosen from the many available, were tested at a low level and a high level and in all possible combinations (2 •) plus four center points. The 36 formu- lations were evaluated using six or eight curls per formulation. These factorials were analyzed (by linear regression) to determine the most effective ingredient or combinaton of ingredients. The best formula- tions arrived at by the statistical design and those previously considered best are listed in Table IV. Again, using Resin R-2 as an example and referring back to Table Ill, it can be seen that oleyl alcohol and per- fume had a negative influence on curl retention and were omitted from

NEW APPROACHES TO HAIR SPRAY EVALUATION Table IV Formulations for Studying Curl Rctcntion 633 Resin R-2 (dry) 2 AMPD • 0 Oleyl alcohol 0 Perfume a 0 Isopropyl myristate Anhydrous denatured ethanol 32 Freon 11 propellant 39 Freon 12 propellant 26 Weight Per Cent 6" 7 (Best) b 00 1.50 05 0.10 20 ... 15 ... 0.40 60 38.00 00 30.00 .00 30.00 Resin G-2 (50% solids) 3.00 3.00 AMPD e 0.10 0.04 "Acetulan"* 0.10 . . . Isopropyl myristate 0.10 0.20 Perfume! 0.50 0.50 Anhydrous denatured ethanol 36.20 36.26 Freon 11 propellant 30.00 30.00 Freon 12 propellant 30.00 30.00 Resin D (50% solids) 3 Acetulan e 0 Oleyl alcohol Isopropyl myristate Perfume -t 0 Anhydrous denatured ethanol 36 Freon 11 propellant 30 Freon 12 propellant 30 00 3.00 20 0.20 0.20 0.20 50 0.50 30 35.90 00 30.00 00 30.00 a Formulations previously considered the best hard-holding formulation or one recommended by the resin manufacturer as being a good "hard-to-hold" product. b Formulations derived from the statistical design for optimizing the concentrates. c 2-Amino-2-methyl-l,3-propanediol, Commercial Solvents Corp., New York, N.Y. a The perfume used in Formulation 6 was unknown because this product was supplied by the resin manufacturer and the perfume was unidentified. In the experimental design, a standard perfume was used and it was rejected because it adversely affected the holding power. Subsequently, a special low plasticizing perfume was used which was developed specifically for this resin by the Haarmann and Reimer Corp. of Union, N.J. This perfume provided a slightly beneficial effect on the holding power. e Amerchol, a Unit of CPC International, Inc., Edison, N.J. ! GD-6763-1, Givaudan Corp., Clifton, N.. J. Formulation 7, and that AMPD and isopropyl myristate were beneficial and were included. The curl retention rs. time curves for Formulations 6 and 7 are in Figs. 10-12. The following improvements in curl retention were ob- tained after 3 hours at 98% RH.: