Modeling for Ink Permeability and Calculating the Penetration Depth inside Paper

To study deeply ink penetration condition inside the paper, an ink permeability model on the basis of Kubelka-Munk theory is built up in the paper, and infer out the formula of ink penetration depth, consisting of paper thickness and various brightness. And then the test value and calculation value of ink penetration depth are compared. The study results show that the two values are almost the same, so the state of ink penetration depth can be effectively estimated just by paper brightness.