| 摘要 |
<p>This invention provides a white laminated polyester film for metallic plate lamination work, consisting of a laminated film comprising a layer (the layer A) composed of a copolyester A and a layer (the layer B) composed of a copolyester B characterized in that (I) (i) the copolyester A is a copolyester having a melting point of from 210 to 245 DEG C and containing 0 to 15% by weight of rutile titanium oxide having an average particle diameter of from 0.1 to 0.5 mu m, (ii), the copolyester B is a copolyester having a melting point of from 210 to 245 DEG C and an intrinsic viscosity of the polymer part of from 0.46 to 0.66 and containing 10 to 50% by weight of rutile titanium oxide having an average particle diameter of from 0.1 to 0.5 mu m, (II) the intrinsic viscosity ( eta A) of the polymer part of the copolyester A and the intrinsic viscosity ( eta B) of the polymer part of the copolyester B satisfy the following relationship: <MATH> (III) the ratio of the apparent density ( rho ) to the calculated density ( rho 0) of the whole laminated film ( rho / rho 0) satisfies the following formula: <MATH> wherein <MATH> in the above formula, rho : apparent density (g/cm<3>) of the whole laminated film, rho 0 : calculated density (g/cm<3>) of the whole laminated film, rho i : density (g/cm<3>) of the polymer part of each copolyester, rho t : density (g/cm<3>) of rutile titanium oxide: Xi : thickness ( mu m) of each layer: Wi : concentration (wt.%) of rutile titanium oxide in each copolyester: n : number of copolyester layers. The white laminated polyester film for metallic plate lamination work disclosed in the present invention has excellent white masking power, workability, aromaproofness and heat-resistance and causing little abrasion of rolls.</p> |
