Patent ID: 10589490

Abstract:
A laminated polyester film includes a pigment-containing polyester layer A and wax-containing polyester layers B1 and B2 on both sides of the polyester layer A, wherein the film satisfies formulae (I) and (II), and the coefficient of variation of water contact angle for each layer B1 and layer B2 is not less than 0% and not more than 10%, when the contact angle with water is measured 10 times at arbitrary defined positions within the range of 200 mm×200 mm: Wb1>Wa  (I)Wb2>Wa  (II) wherein Wb1 and Wb2 represent the wax content per unit area of the layer B1 and layer B2 respectively, and Wa represents the wax content per unit area of the layer A, and wherein the coefficient of variation represents a value obtained by dividing the standard deviation in values measured 10 times by the average value.