422 A. PQ-67 ( JOURNAL OF COSMETIC SCIENCE o"-)n { ? H PH (CH2CHP)x (CH2CHj Hz·H CH 3�·CH3 Cl C12H25 Figure 1. Cationic conditioning HEC polymers. also damaging it, and thus the need for products that can mitigate and repair this damage is increasing dramatically. The current offering of cationic conditioning poly- mers is quite broad and is expanding, with HEC-based polymers representing a signifi- cant portion of this market. Varying structural parameters of these polymers, such as molecular weight, cationic and hydrophobic substitution and/or the degree of ethox- ylation significantly impacts their performance on hair and creates the much needed diversity of properties and benefits. This paper describes the impact of the charge substitution (CS) in combination with the hydrophobic substitution (HS) on the depo- sition properties and overall conditioning of PQ-67 polymers. New compositional fea- tures enhanced the performance of the experimental high charge density PQ-67 poly- mers, which were found superior when compared to any of the competitive benchmarks used in this study in deposition of performance ingredients and for overall conditioning. This performance makes the new structures a valuable addition to the family of cationic conditioning polymers. These polymers were found to be especially useful to manage hair types that benefit from volume control and extra-conditioning, such as unruly, difficult-to-manage hair or for Asian hair types. 6 RES UL TS AND DISCUSSION POLYMER COMPOSITION New experimental high charge density PQ-67 polymers belong to the family of high viscosity quaternized hydroxyethyl cellulose (HEC) derivatives with cationic substitu- tion of trimethyl ammonium and dimethyldodecyl ammonium (Figure lA) described in (1) and (2) and recently commercialized for personal care applications by Amerchol Corporation and the Dow Chemical Company under the trade name of Polymers Soft- CAT™ SL and SK. Similar to the commercially available grades, experimental PQ-67 samples described in this paper were produced by reacting HEC polymers with 3-chloro- 2-hydroxypropyldodecyldimethyl ammonium chloride and 2,3-epoxypropyltrimethyl ammonium chloride in aqueous isopropanol (2). In this work we used polymers made of a high viscosity HEC with the degree of ethoxylation similar to one of commercially 6 We are currently in progress evaluating performance of experimental high charge density PQ-67 polymers on Asian hair.

2006 TRI/PRINCETON CONFERENCE 423 available PQ-67 grades such as Polymers SoftCAT SL and SK. Low levels of hydrophobic dimethyldodecyl ammonium substitution (HS :::=;: 0.01) were used to impart hydropho- bic character to these polymers. Several structural parameters of cationic cellulosic ether derivatives, such as PQ-67 (Figure lA) and their non-hydrophobic structural analogs, PQ-10 (Fig. lB) polymers have a profound impact on their performance on hair and skin. These parameters include molecular weight (Mw), cationic charge (CS), as well as the degree of the side chain substitution with ethylene oxide (EO MS). Examples of such structure-performance relationships for PQ-10 polymers in surfactant systems were previously described in industry sources (3-6). On the other hand, the structural potential of PQ-67 composi- tions is much less explored and understood. In addition to the structural features already present in PQ-10, the structure of PQ-67 polymers offers one more variable-the degree of hydrophobic substitution (HS), which is another useful tool for modifying, control- ling, and improving certain performance aspects of these polymers on hair (1) and skin (7). The new results presented below demonstrate that increasing the cationic charge to above 2 wt.% N in the hydrophobically modified quaternized HEC polymers, such as PQ-67, resulted in a several fold boost of their deposition and delivery properties, and significantly improved the overall performance of these polymers on hair, especially non-chemically treated, coarse, difficult to manage and unruly hair types. The high charge density PQ-67 polymers were evaluated in shampoo formulations using objective quantitative lab methods and subjective panel evaluation on hair tresses. Commercial conditioning polymers: PQ-67 with charge density less then 1.45 meq/g (SoftCAT™ SL and SK) and cationic guar CTaguar® C-13S) were used as performance benchmarks. PERFORMANCE IN SHAMPOOS WITH SILICONES The principal intent of shampooing is to clean the hair. However, products that are designed solely for cleansing can leave hair tangled and unmanageable when wet, and raspy dry and dull-looking upon drying ((1) and references therein). As previously described in (1), many conditioning polymers and various other perfor- mance ingredients, e.g. insoluble silicones, can improve the hair condition by reducing the combing friction of hair and providing a soft, smooth feel and healthy, shiny appearance. Cationic polymers, such as PQ-10, PQ-67, and cationic guar, are known to work in these ways, in these systems, alone or in combination with other actives. They are assumed to form a polymersurfactant complex (coacervate phase) that separates and precipitates onto the hair during the rinse-off cycle (1,8-10). Coacervates can optionally incorporate performance ingredients such as silicones, fragrance, sunscreens, and other benefit agents thus assisting in their deposition on hair (1,3,4). Experimental polymers described in this paper are conjectured to perform along this line. Deposition of silicones on hair has been evaluated in two shampoo systems that included different surfactant bases and different types of silicones: Shampoo Formulation A con- taining sodium laureth sulfate (SLES)/ disodium cocamphodiacetate (DSCADA), 1 wt.%