Toyobo Co., Ltd.

Teijin Film Solutions Limited

Naoki Iyo

Shinji Yano

Mitsuo Tojo

A biaxially drawn colored polyester film includes at least two layers: a surface layer (layer A) mainly composed of polyester having a melting point TmA of 230 to 260&#xb0; C. and modified polyolefin wax, layer A having a polymer component with intrinsic viscosity of 0.46 or more, the modified polyolefin wax with an amount of 0.2 wt % or more based on the weight of the composition, coloring pigment with an amount of 10 wt % or less, and a water contact angle of less than 70&#xb0; on an outer surface; and a substrate layer (layer B) mainly composed of polyester having a melting point TmB of 230 to 260&#xb0; C. and coloring pigment, layer B having a polymer component with intrinsic viscosity of 0.46 or more and the coloring pigment with an amount of more than 10 wt % and 50 wt % or less; wherein |TmB&#x2212;TmA| is 4&#xb0; C. or less.

Biaxially drawn colored polyester film for laminating metal sheet

An oriented polyester film containing antioxidant and modified polyolefin wax in a surface layer on at least one side thereof, wherein the oriented polyester film is such that the modified polyolefin wax contained in said layer is present in an amount that, as measured based on weight of a composition at said layer, is not less than 0.1 wt % but less than 3.0 wt %, and wherein the modified polyolefin wax is such that acid value thereof is not less than 1 mg KOH/g but less than 50 mg KOH/g, 3 wt % weight loss onset temperature thereof is not less than 300&#xb0; C., weight-average molecular weight thereof is within a range that is 3,500 to 65,000, and the antioxidant is present in an amount that, as measured based on the weight of the composition, is not less than 0.02 wt % but less than 0.35 wt %.

Oriented polyester film

A colored biaxially stretched polyester film for metal plate attachment and forming processing, includes three layers: opposite surface layers (layers A) that contain substantially no coloring pigment and are made of a copolyester having an intrinsic viscosity of 0.65 to 0.80 and a melting point (TmA) of 230 to 260&#xb0; C.; and a core layer (layer B) that has a coloring pigment content of more than 10 wt % and 50 wt % or less and is made of a copolyester having an intrinsic viscosity of 0.55 to 0.70 and a melting point (TmB) of 230 to 260&#xb0; C. The film has a surface roughness within a range of 10 to 40 nm, and (TmB&#x2212;TmA) is 4&#xb0; C. or less.

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Tokyo, Japan

Naoki Iyo