摘要 |
<p>A protective cardboard for planographic printing plates has a cardboard main body, a moisture-proofing layer on both surfaces of the cardboard main body, and an adhering paper adhered onto the moisture-proofing layer. By the adhering paper contacting an interleaf sheet, a coefficient Y of static friction between the protective cardboard and the interleaf sheet is equal to or less than a coefficient X of static friction between the interleaf sheet and an image forming surface of the planographic printing paper (i.e., Y</=X). <IMAGE></p> |