JOURNAL OF COSMETIC SCIENCE 74 absorbency. On the other hand, synthetic polymer-based emulsions are on the positive axis of Component 1, with the opposite rheological and sensorial properties from cellulose- derivative and control-based emulsions. Cellulose derivatives are closer to each other than to the control sample, with greater fi rmness, absorbency and slipperiness, and less spread- ability whereas PVP was distinct from the PAA and PAA Na group, with more moisture and oil feel in the synthetic polymer group. PCC ANALYSIS PCC were calculated to analyze how seven rheological parameters (except the damping factor) infl uenced 13 sensory attributes. Among them, four sensory attributes were mostly correlated with the rheological parameters studied the PCC results are listed in Table VI. Firmness was most signifi cantly correlated with the rheological parameters, with a sig- nifi cance of 0.01 and PCC of 0.87–0.97, followed by Absorbency and Peak after pick- up, with a signifi cance of 0.03 and PCC of 0.80–0.84 and 0.83–0.93, respectively. The PCC of spreadability has a negative number, -0.80 to -0.87, which means the samples with higher viscosity have lower spreadability. The results showed that emulsions with high rheological parameters, such as viscosity and yield stress, tend to have higher fi rm- ness, peak after pick up, absorbency, and lower spreadability. But for the parameters of the after-feel factor such as tackiness or moisture, no signifi cant PCC were shown. The PCC analysis suggests that a rheology test is more suitable for predicting primary skin feel parameters rather than after-feel parameters. CONCLUSION The purpose of this study was to illuminate how and to what extent polymer structure differences and rheological properties can affect the fi nal skin sensory attributes of different Figure 2. PCA results based on the rheology and sensory parameters. (Zone 1 from top to bottom: viscosity at 1 s-1 viscosity at 0.1 s-1 shear stress at crossover point viscosity at 10 s-1 G′ viscosity at 100 s-1 greasiness G″ absorbency. Zone 2 from top to bottom: gloss (after-feel) ease of pick-up oil feel and tackiness.)

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