PRODUCTION AND OPTIMIZATION OF PIGMENTS AND BINDER IN LOW-COST EMULSION HOUSE PAINT USING RESPONSE SURFACE METHODOLOGY

Paint is any liquid, liquefiable or mastic composition which after application to a substrate in a thin layer is converted to an opaque solid film. The objective of this research was to investigate the effects of some basic paint components i.e., prime pigment, extender pigment and binder on pH, viscosity and density on white emulsion paint formulation. The research was aimed at producing low-cost white emulsion house paint and optimizing the pigments and binder in other to obtain the optimal conditions for which the best paint formulation can be obtained using the Response Surface Methodology (RSM). The pH, density, viscosity and cost were chosen as the responses while the prime pigment, pigment extender and binder were selected as the factors. Twenty (20) different samples of white emulsion house paint were successfully formulated and produced using Central Composite Design. The physico-chemical properties of twelve (12) of the produced paints fell within the conventional specified range by Nigeria Industrial Standard. The results obtained revealed that the pH, viscosity and density were largely affected by the concentration of the prime pigment, pigment extender and binder. Also , the analysis of the variance (ANOVA) of the models showed that the developed models for viscosity, density, pH and cost were significant with F-values of 109.19, 99.55, 10.31 and 2278.53 respectively, and P-values less than 0.05 (P<0.05). In addition, the generated optimum conditions of the desired paint formulation were 66.85 g for the prime pigment, 440.56 g for the pigment extender and 0.108 L for the binder while the quality test optimum conditions were 5.819 poise for viscosity, 1352.836 g/L for density and 7.035 for pH at a cost of ₦336.465. Using the optimum conditions to validate the experiment, the obtained experimental values of 5.95 poise of viscosity, 1380 g/L of density and pH of 7.30 were close to the predicted values and it confirmed the validity and adequacy of the predicted models. While Percentage error deviation of 2.26%, 2.0%, 2.64% and 2.5% were calculated for the viscosity, density, pH and cost, respectively.