Abstract: The present invention addresses the problem of providing a laminated polyester film that has high reusability and is suitable for processing during a post process. This laminated polyester film comprises a polyester film and a layer X that satisfies the following conditions. Condition 1: 20??XP?45 Condition 2: 3.0??XH?10?XP (mN/m): Polar component of the surface free energy of the layer X ?XH (mN/m): Hydrogen bond component of the surface free energy of the layer X.

Abstract: A multilayered polyester film which comprises a polyester film and, disposed on at least one surface thereof, a layer X which has a contact angel HX(1) with water of 0-60°, wherein the layer X has a degree of crystallinity C(0) of 0-30%. HX(1): Contact angle at one second after water has come into contact with layer X. A polyester film having excellent recoverability is provided by disposing a layer X on at least one surface of a polyester film, the layer X having a regulated contact angle with water and a regulated degree of crystallinity.

Abstract: A biaxially oriented thermoplastic resin film has at least one surface of which has protrusions each having a height of 1 nm or more and less than 2 nm at a density of 1×107 to 1×109 protrusions per mm2. The thermoplastic resin film is capable of suppressing generation of coarse protrusions and contaminants, and defects in a processing process while having slipperiness.

Abstract: A biaxially oriented thermoplastic resin film has at least one surface of which has protrusions each having a height of 1 nm or more and less than 2 nm at a density of 1×107 to 1×109 protrusions per mm2. The thermoplastic resin film is capable of suppressing generation of coarse protrusions and contaminants, and defects in a processing process while having slipperiness.

Abstract: An object of the present invention is to provide a polyester film whose wet heat resistance is not reduced even when incorporated into a solar cell backsheet or solar cell. The polyester film according to the present invention has a peak count SPc_L (400 nm) of 100 to 700 and a peak count SPc_H (4,000 nm) of not more than 10 on at least one surface, the polyester film having an amount of terminal carboxyl groups of 0 to 20 eq/ton.

Abstract: A polyester composition contains polyester, a phosphoric acid and an alkali metal phosphate, a phosphorous element content P (mol/t) is 1.8 mol/t or more and 5.0 mol/t or less relative to the whole of the polyester composition. The polyester composition contains at least one metal element of Mn and Ca, any divalent metal element content other than Mn and Ca is 5 ppm or less, and when an alkali metal element content relative to the polyester composition is denoted by M1 (mol/t), and a total amount of Mn element content and Ca element content relative to the polyester composition is denoted by M2 (mol/t), a metal element content M (mol/t) in the polyester composition which is calculated by expression (i) below and the phosphorous element content P (mol/t) satisfy expression (ii): (i) M=M1/2+M2 and (ii) 1.1?M/P?3.0.

Abstract: [Problem] An object of the present invention is to provide a polyester film whose wet heat resistance is not reduced even when incorporated into a solar cell backsheet or solar cell. [Means for Solution] The polyester film according to the present invention has a peak count SPc (400 nm) of not less than 100 and a peak count SPc (4,000 nm) of not more than 10 on at least one surface, the polyester film having an amount of terminal carboxyl groups of 0 to 25 eq/ton.

Abstract: A polyester composition contains polyester, a phosphoric acid and an alkali metal phosphate, a phosphorous element content P (mol/t) is 1.8 mol/t or more and 5.0 mol/t or less relative to the whole of the polyester composition. The polyester composition contains at least one metal element of Mn and Ca, any divalent metal element content other than Mn and Ca is 5 ppm or less, and when an alkali metal element content relative to the polyester composition is denoted by M1 (mol/t), and a total amount of Mn element content and Ca element content relative to the polyester composition is denoted by M2 (mol/t), a metal element content M (mol/t) in the polyester composition which is calculated by expression (i) below and the phosphorous element content P (mol/t) satisfy expression (ii): (i) M=M1/2+M2 and (ii) 1.1?M/P?3.0.