CARBON BLACK COLLOIDAL SOLUTION AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A manufacturing method of a carbon black colloidal solution is provided to be excellent in the stability of dispersion. CONSTITUTION: The manufacturing method of a carbon black colloidal solution comprises the steps of: mixing a carbon black, a surfactant and a deflocculation agent; controlling the mixture less than 7 pH; crushing the consequence; and the carbon black colloidal solution can stably disperse the minute dispersed particle by controlling the colloidal solution less than 7 pH, desirably 3 to 4 pH to be used as a coating solution to coat the surface of a picture tube to particularly improve the contrast of a picture indicating element.