Flexible printing using water-based ink, water-based resin particle size smaller. Coated paper is a kind of porous material, pore is formed by fiber and pigment particles coated paper ink absorption, the basis of their assessment on ink absorption ability is an important index of coated paper printing ink absorbency. The pore decide the printing ink to the coated paper surface after ShenTouLiang and penetration rate. Part of printing, printing ink in the printing pressure under the action of directly pressed into the pore of coated paper, another part of the ink transferred to the paper, after the ink pigment particles diameter smaller fiber gap in the fiber link under the action of capillary absorption material, and the ink pigment particles remain in coated paper surface drying quickly, so the surface of the coated paper microporous sex good,