Estudo para a melhoria do poder tintorial de pasta aquosa amarelo óxido e vermelho óxido para uso em tintas

Abstract

Architectural paints are mostly made up of solvent, resin, additives and pigment, the latter being responsible for providing beautification and protection. The pigments can be of organic origin, which degrades quickly by the action of ultraviolet radiation, offering less resistance to weathering, or of inorganic origin, which have stronger intermolecular interactions. To get the best performance from the pigments, it is crucial that it is well dispersed, so that each particle present can cover a larger area. Therefore, the elaboration of pigment dispersion paste has proven to be efficient to ensure the highest possible tinting power. This work aims to evaluate different formulations of the dispersion paste of the yellow and red oxide pigments to obtain an improvement in the tinting power and in the manufacturing process. V1 formulations use common dispersing agents and HASE-type thickeners, while V2 formulations use combined-action dispersing agents, which disperses and moistens and HEUR-type thickeners, which provide better stability and lower viscosity to the materials. V1 formulations use common dispersing agents and HASE-type thickeners, while V2 formulations use combined-action dispersing agents, which disperses and moistens and HEUR-type thickeners, which provide better stability and lower viscosity to the materials. The results of the tinting power showed an improvement for the V2 formulations of the dispersion pastes of these pigments, combined mainly with the use of dispersing and wetting agent, ensuring efficiency in the dispersion process, observed by the reduction in particle size, and the use of rheological modifiers of the HEUR type, which provided greater stability and lower viscosity of the samples.