| 摘要 |
<p>A cover film for hard copy printing paper, which is used in transfer-forming a colorless clear protection layer that inhibits the passage of ultraviolet rays onto the surface of a hard copy printing paper (4) such as color copy-printed paper obtained by transferring a transfer paper to which are applied sublimable dyestuffs onto a printing paper. The feature of the cover film resides in that at least a layer (2, 3) is formed on a substrate (1), the layer (2, 3) having a glass transition temperature of higher than 40oC, and a coefficient of water absorption of less than 2% (as evaluated in accordance with ASTMD 570 by immersing a film which is 0.01 in. thick in water at 23oC for 24 hours). The protection layer formed by using the cover film of the present invention prevents adverse effects caused by the migration of dyestuffs of the printing paper under high-temperature and high-humidity conditions.</p> |
