In this paper, we propose a physically based model for the printing process in the virtual woodblock printing for improvement of printing quality. Virtual printing is a simulation of real printing using "woodblocks", "a paper sheet", "a BAREN (Japanese squeegee)", and "inks" in a virtual 3D space. A print is synthesized by an interaction among them, and it is very important to study physical properties and behaviors of the virtual items. We focus on the property and the behavior of ink and study a variety of effects due to the degree of moisture of the ink. This improvement enables the virtual printing to synthesize Japanese traditional multicolor prints Ukiyo-e.