| 摘要 |
PROBLEM TO BE SOLVED: To improve image coloring density and sharpness by laminating in turn an ink acceptable layer and surface treatment layer on at least one surface of a base material, and by the use of a colloidal silica gel of a predetermined primary particle diameter in the surface treatment layer. SOLUTION: A colloidal silica gel used for the surface treatment layer of an ink jet recording medium is defined by a primary particle diameter and coagulation particle diameter. Employing the colloidal silica gel allows superior dispersibility to be obtained in coating liquid to render the coating liquid stable and form surface treatment for accomplishing excellent image characteristics. Concretely, the primary particle diameter is 5-30 nm, preferably 9-25 nm, especially preferably 10-18 nm, and most preferably 11-14 nm. In addition, the coagulation particle diameter is 18-250 nm, preferably 30-110 nm and most suitably 35-75 nm in the colloidal silica gel attains particularly superior image characteristics. Also, since an ink absorption speed is fast, it is adapted to high speed printing. |
