| In this study, a series of dispersants were used to treat the organic pigment. With a M-110EHI microfluidizer, the organic pigment was shattered into super-fine particles less than 200 nanometer and dispersed in water. The factors that affect the stabilization of the aqueous dispersion systems were also discussed.In the experiments, the spectrophotometer was used to measure the ratio of absorbency, which was used to indicate centrifugal sedimentation rate of the systems. The mean size and distribution of the particles were measured with a Malvern laser sizer. A Jsm-5600LV scanning electron microscope was used to observe the configuration of the broken pigment particles. The Zeta voltage of the pigment surface was measured with a Malvern Zeta meter. The viscosity of the system was measured with a NDJ-1 rotary viscosity meter at 25℃ .It is shown that the centrifugal sedimentation rate of the system is lowest after 25 dispersions at 22,000psi pressure. The HLB values of the dispersants have great influence on the stabilization of the systems. When the HLB value is 13-15, the system has best stabilization and rheology. The optimal ratio of pigment to dispersant was studied. For the anionic dispersants, the optimal ratio is 8:1-12:1. For the nonionic dispersants, the optimal ratio is 1:1. For the polymeric dispersants, the best ratio is 4:1. The pH value of the system has little influence on the nonionic dispersants. When the pH value is 7-9, the anionic and polymeric dispersant have best dispersion abilities. With the increasing of the co-solvent diglycol, the viscosity and the particle size of the systems both increase after treatment. The centrifugal sedimentation rate of the system dropped to a lowest point at some ratio of diglycol to deionized water. When the ratio of diglycol to deionized water is 3:7, the systems have the best abilities to endure the change of the temperature for all kinds of dispersants.
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