Dispersant is a surfactant with two opposite properties, lipophilicity and hydrophilicity, in the molecule. It can evenly disperse the solid and liquid particles of inorganic and organic pigments that are difficult to dissolve in liquids, and at the same time prevent the sedimentation and agglomeration of particles, forming the amphiphilic agent required for a stable suspension.
The role of the dispersant is to use a wetting dispersant to reduce the time and energy required to complete the dispersion process, stabilize the dispersed pigment dispersion, modify the surface properties of the pigment particles, and adjust the mobility of the pigment particles. The specific advantages of the dispersant are as follows:
① Improve gloss and increase leveling effect.
② Prevent floating color and flowery.
③ Improve coloring power.
④ Reduce viscosity and increase pigment loading.
⑤ Reduce flocculation.
⑥ Increase storage stability.
⑦ Increase color development, increase color saturation, increase transparency (organic pigments) or hiding power (inorganic pigments).
The composition of ceramic slurry is a complex system, generally composed of ceramic powder, solvent, dispersant, adhesive, plasticizer, flocculant, mineralizer, defoamer, lubricant, etc. In ceramic slurry, powder particles are suspended in the solvent medium and have a tendency to agglomerate and precipitate. The role of ceramic-specific dispersants is to hinder this flocculation phenomenon, so that the particles can be evenly dispersed and stably suspended. Its dispersion mechanism is mainly “electrostatic repulsion” and “steric hindrance” effects. Simply put, the role of ceramic-specific dispersants is to prevent ceramic slurry from agglomerating and precipitating; to make it evenly dispersed.