| 摘要 |
PROBLEM TO BE SOLVED: To provide a wide ink selecting range and good transparency and to prevent a crack, a curl or the like by incorporating an ink receptive layer containing an alumina hydrate having a crystallite size of a specific value in the specific surface direction and a Boehmite structure in a specific mean particle thickness on a base material, and specifying a parallelism. SOLUTION: In a shape of an alumina hydrate exhibiting a Boehmite structure, its mean particle thickness in a flat plate-lie state is in a range of 2.0 to 6.0 nm, and a mean particle size is preferably in a range of about 1 to 50 nm. When a crystallite size (020) is obtained from a medium to be recorded formed with an ink receptive layer containing the hydrate by an X-ray diffraction method of a crystal structure of the hydrate, the size is in a range of 5.0 to 8.0 nm. IF the size falls within this range, its transparency can be upgraded without impairing self-film formability of the hydrate. A parallelism in the medium is in a range of 30 to 1,000. If the parallelism falls within this range, a coating defect, a white sheet curl, or a curl after printing can be prevented. |
