Preparation method of pigment yellow 139, automatic control system and coloring composition

Abstract

The invention relates to a preparation method of pigment yellow 139, an automatic control system and a coloring composition, and the preparation method comprises the following steps: step a, dispersing barbituric acid in a water phase system, and adding an alkaline compound to make the system become an alkaline system; step b, dropwise adding a low-carbon alcohol solution containing 1, 3-diimino isoindoline and an inorganic acid solution in a parallel flow manner, so that a reaction system is gradually converted into an acidic system from an alkaline system and is subjected to a condensation reaction; and c, after the reaction is completed, carrying out solid-liquid separation, and washing with water to obtain a pigment yellow 139 crude product. The automatic control system applied to the preparation method comprises a process sensor group, an execution mechanism group and a control unit. The coloring composition comprises the pigment yellow 139 crude product and the like. The invention relates to the technical field of isoindole pigment preparation, a three-step process is adopted, and an innovative production technology of organically combining alkalization dispersion, parallel flow acidification and efficient separation is adopted, so that the reaction conversion rate and the particle size uniformity of a crude product are improved, and the dosage of an organic solvent, waste acid water discharge and overall energy consumption are also remarkably reduced.

Images