## 3 Results and Discussion
### Color Characterization  
Color properties, such as lightness L\({}_{\rm ab}\)*, hue h\({}_{\rm ab}\)* and Chroma C\({}_{\rm ab}\)*, were calculated. They are represented in the CIELAB color space to compare the color gamut from both hybrid pigments PC and PE. Once again, Table 4 shows how the different applied conditions changed the color perception of the hybrid pigments. We did another ANOVA calculation to know the factors that influenced this variance. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**REF.** & **L*** & **C\({}_{\rm ab}\)* & **REF.** & **L*** & **C\({}_{\rm ab}\)*** \\ \hline nPC.1 & 69.77 & 11.08 & nPE.1 & 74.37 & 7.54 \\ nPC.2 & 68.16 & 15.05 & nPE.2 & 71.57 & 6.81 \\ nPC.3 & 68.59 & 12.96 & nPE.3 & 76.25 & 4.96 \\ nPC.4 & 76.13 & 9.23 & nPE.4 & 80.55 & 2.58 \\ nPC.5 & 62.18 & 13.69 & nPE.5 & 65.90 & 9.20 \\ nPC.6 & 76.02 & 13.47 & nPE.6 & 81.17 & 4.65 \\ nPC.7 & 53.05 & 10.62 & nPE.7 & 65.74 & 12.63 \\ nPC.8 & 55.41 & 14.22 & nPE.8 & 83.92 & 4.07 \\ nPC.9 & 70.42 & 11.13 & nPE.9 & 82.44 & 3.68 \\ nPC.10 & 55.87 & 13.79 & nPE.10 & 71.62 & 9.85 \\ nPC.11 & 71.37 & 6.54 & nPE.11 & 79.94 & 4.64 \\ nPC.12 & 69.27 & 8.78 & nPE.12 & 78.85 & 5.02 \\ nPC.13 & 62.34 & 15.04 & nPE.13 & 73.01 & 7.44 \\ nPC.14 & 59.30 & 13.33 & nPE.14 & 71.37 & 7.62 \\ nPC.15 & 73.14 & 11.52 & nPE.15 & 77.49 & 4.44 \\ nPC.16 & 74.63 & 7.09 & nPE.16 & 77.72 & 7.90 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: L* and C\({}_{\rm ab}\)* values for the PE and PC hybrid pigments under different synthesis conditions [1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12; 13; 14; 15; 16] using the D65 illuminant and the CIE-1931 XYZ standard observer. Figure 3: Calibration lines from dyes PC (\(\lambda\) 615 nm) and PE (\(\lambda\) 545 nm) in water dilutions from the initial buffer phosphate concentration. Figure 4 depicts the color attribute differences in the hybrid pigments from PE. The nPE.16 samples displayed a yellowish hue, while the other samples were reddish, or even bluish, such as nPE.7. Chroma and lightness showed significant differences; for example, nPE.7 or nPE.5 were darker and more chromatic. However, none of these samples represented the optimal conditions for achieving the most varied color gamut. ANOVA calculations had to be done to understand the factors that influenced the final color perception. Figure 5 represents the interaction factors that were significant in the ANOVA calculation. All the analyzed factors were significant for the chroma or lightness of PC or PE. However, significant interactions depend on PC or PE and perception attribution C\({}_{\text{ab}}\)* or L*. Figures 5-8 show that, to gain a wide color gamut from a starting point with the lowest lightness and the highest chroma values in PC, the high dye concentration should be used with the L nanoclay without employing surfactant and silane additives. The M clay results were more chromatic at a high concentration than the L blue pigments (PC). However in the pink pigments (PE), the most chromatic samples were achieved with L with no surfactant or silane additives. In these samples, the less chromatic and lighter samples were found at the medium concentration level (1%), with worse results than at the lowest concentration. This was probably due to the agglomeration phenomenon in the nanoclay structure at this concentration. Future applications must take into account either the interactions that occurred between the dye concentration and clay origin or the additives concentration to control both color gamut and color perception. The dye concentration showed nonlinear behavior in the color response, which must also be considered. Figure 4: Interactions plot of the PE and PC Ads (%) responses under DOE conditions. Figure 5: Graphic CIELAB plots for the PE hybrid pigments under different synthesis conditions [nPE.1–nPE.16] using the D65 illuminant and the CIE-1931 XYZ standard observer. **Left**: CIE-a* b* color diagram; **right**: CIE-Cab* L* color chart. Figure 6: Main effects and interaction plots from the Cab* response in the PC pigments.