| 摘要 |
PURPOSE:To contrive modification of flatting and transparency, by a method wherein since the title film is a biaxially oriented laminated polyester film comprised of at least two layers and satisfies general formulas 1-8 at the same time. CONSTITUTION:Polyester raw materials obtained by performing mixing and adding of fine particles such as kaolin or silica along with an additive agent such as a stabilizer or a coloring agent or a defoaming agent or an organic lubricant or polyalkylene glycol at need and polyester raw materials prepared separately are dried independently. They are extruded by separate extruding machines, two kinds of raw materials are made complex so that they becomes surface layers each other, cooled and solidified on a casting drum and unoriented polyester sheet comprised of two layers is formed. The obtained sheet is oriented secondly in the first axial direction, ordinarily in a longitudinal direction. Then although the obtained biaxially oriented film is fixed thermally for 1sec. to 10min. at 200-250 deg.C, it is important to slacken the film in the direction of a width of the film in a thermally fixing zone. With this construction, a film for printing display body having excellent transparency, flatting and dazzle preventive properties can be obtained. |
