The Effect of Grinding Conditions on Disperse Particle Size of Ultrafine Organic Pigment Water-Based Dispersion System

摘要

In recent years, with the gradual emphasis on environmental protection, more and more extensive attention has been paid to the water-based ink in the market. The dispersion of organic pigments has been a key part of the research of water-based pigment inks. In the use of organic pigments, the pigment must be effectively dispersed, so that it has a fine and uniform particle size distribution and finally forming a stable dispersion system. The dispersion effect of the pigment is determined by many factors. In this paper, the effect of grinding speed, grinding time and the mass ratio between grinding medium and ink slurry on the dispensability of organic pigment yellow 100 was studied mainly from the viewpoint of the grinding process conditions. It is found that the particle size of the pigment decreases first and then increases with the increase of the grinding speed. When the rotational speed is 3100-3200 r/min, the average particle size reaches the minimum of 278 nm. Besides, the particle size of the pigment decreases first and then hold steady with the increase of the grinding time. When the grinding time is 1 h, the average particle size is the smallest. Furthermore, the particle size of the pigment decreases first and then increases with the increase of the mass ratio between grinding medium and base ink. When the mass ratio is 2, the particle size is the smallest and the dispersion effect is the best.