Ultramarine Blue, an Old pigment, a New Process

Abstract

Ultramarine Blue is an inorganic pigment that has been used for centuries all over the world. This Sodium Alumino Sulfosilicate is known as Lapis Lazuli in its natural form. In 1826, the synthetic Ultramarine blue was produced through a batch process. It was only in 1993 that the continuous production process for this pigment was invented. Today, the industrial plant is running under the same conditions as the pilot plant. This evolution in production has to bring at least some quality improvement in pigments over the batch process and preferably some specific advantages for the end-users. Some of these studies are presented in this chapter. Ultramarine blue pigments give similar L, a, b values when they are compared in the same matrix. A continuous production process of Ultramarine blue pigment answers the demand on color as well as existing batch production process, improves on consistency, and helps in final formulation. These are the first parameters to satisfy color and other factors (tinting strength, dispersability, thermal stability, weatherability) that will influence the final formulations but these are still under evaluation.