In the coating process, the paper coating was performed in various shear forces. Therefore, the rheological properties of the coating had profound effects on the quality of coated paper. In order to achieve the good rheology, paper coating required the addition of thickener or rheology modifiers. Organic bentonite was a kind of thixotropic ge1, which was extensively used in a number of applications as rheology modifier to modify the rheology and control the stability of systems.