| 摘要 |
PROBLEM TO BE SOLVED: To improve dot size of a pigment base in a print on a porous glossy medium. SOLUTION: The dot size is enlarged through re-wetting of the medium surface which receives ink, with any of a dilute polymer solution, a colloidal silica dispersant or a colloidal alumina dispersant. The polymer solution includes other water-soluble polymers such as a polyvinyl alcohol, a polyvinyl acetate copolymer, a polyvinyl pyrrolidone, polyamides, a cellulose derivative or a polyethylene oxide. The range of the particle size of the colloidal silica or alumina dispersant is about 1 to 300 nm. More concretely, firstly, a porous base coat having a plurality of pores is applied on the surface of a non-porous substrate. Then, a first re-wetting liquid is applied on the porous base coat. Next, a porous topcoat is applied on the porous base coat. Finally, a second re-wetting liquid is applied on the topcoat. |
