COEXTRUSION TRANSPARENT BIAXIALLY ORIENTED POLYESTER FILM, ITS MANUFACTURING METHOD AND LID MATERIAL FOR TRAY COMPRISING THE FILM

摘要

PROBLEM TO BE SOLVED: To provide a coextrusion transparent biaxially oriented polyester film having good heat-sealing characteristics and easy to medium peel characteristics and suitably usable as a lid material for a tray comprising a crystalline PET layer.

SOLUTION: The coextrusion transparent biaxially oriented polyester film comprising a base layer B and a heat-sealable outer layer A is characterized in that (1) the outer layer A can be peeled from the crystalline PET layer after it is heat-sealed to the crystalline PET layer, (2) it contains 80-98 wt.% of a polyester (a) and 2-10 wt.% of inorganic and/or organic particles with an average particle size d50of 2.5-12.0 μm and (3) it has a thickness dAof 2.3-10.0 μm. The polyester (a) is composed of 12-89 mol% of an aromatic dicarboxylic acid unit and 11-88 mol% of an aliphatic dicarboxylic acid unit and the ratio d50/dAof the average particle size d50of the particles and the thickness dAof the outer layer A is not lower than 1.0.

COPYRIGHT: (C)2005,JPO&NCIPI