| 摘要 |
PURPOSE:To obtain a film having excellent whiteness and adhesive property, by setting a coated layer on a polyester film having a specific apparent specific gravity and covering factor, being at least monoaxially drawn, having large roughness and containing fine air bubbles. CONSTITUTION:It is necessary that a film prepared by using polyester is such a film that contains fine discontinuous air bubbles on its surface and in its inside, whose apparent specific gravity is 0.4 or more and 1.3 or less, whose covering factor is 0.2 or more and that is at least monoaxially drawn. It is preferable that the draw ratio is 4 or more by area magnification, more preferably 9 or more. When a coated layer is prepared on this film, such a method is preferably employed that film monoaxially drawn in the longitudinal direction is coated with a coating agent and is then drawn in the lateral direction while the coating agent is dried or undried and immediately heat-treated. |
