Back to results
US 2010/0143680 A1Published application
Biaxially drawn multilayer laminated film and method for producing the same
AssigneeTeijin Limited
InventorTaro OYA
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeTeijin Limited
InventorTaro OYA
Estimating the term…
A film composed of a number of layers having different refractive indices and alternately laminated one upon another has characteristic optical properties by light interference. Conventional films having such structure have problems of poor interlaminar adhesivity and low tear strength. The problems are solved by a film having the following constitution. A biaxially drawn multilayer laminated film is composed of alternately laminated 1st layers and 2nd layers at a total layer number of 11 or more. Each layer has a thickness of 0.05 to 0.5 μm. The 1st layer is made of a crystalline thermoplastic resin and the 2nd layer is made of a crystalline thermoplastic resin having a composition different from that of the resin constituting the 1st layer. The maximum light reflectance of the film within the wavelength range of 350 to 2,000 nm is higher than the base line reflectance obtained from a light reflectance curve within the wavelength range of 350 to 2,000 nm by 20% or more.
A biaxially drawn multilayer laminated film composed of the 1st layers and the 2nd layers alternately laminated to a total layer number of 11 or more and subjected to biaxial drawing provided that each layer has a thickness of 0.05 to 0.5 μm, the 1st layer is made of a polyester composition, the 2nd layer is made of a polyester composition having a composition different from the composition of the resin constituting the 1st layer, the maximum reflectance of light within the wavelength range of 350 to 2,000 nm is higher than the base line reflectance obtained by the light reflection curve within the wavelength range of 350 to 2,000 nm by 20% or more, and the ratio of the ethylene terephthalate component in the film is 80% or more based on the total repeating units of the polyester, wherein the crystallization peak measured by differential scanning calorimetry is within the range of 100 to 190° C.
A biaxially drawn multilayer laminated film composed of the 1st layers and the 2nd layers alternately laminated to a total layer number of 11 or more provided that each layer has a thickness of 0.05 to 0.5 μm, the 1st layer is made of a polyester composition, the 2nd layer is made of a polyester composition having a composition different from the composition of the polyester constituting the 1st layer, the maximum reflectance of light within the wavelength range of 350 to 2,000 nm is higher than the base line reflectance obtained from the light reflection curve within the wavelength range of 350 to 2,000 nm by 20% or more, and the ratio of ethylene 2,6-naphthalenedicarboxylate component in the film is 80 mol % or over based on the total repeating units of the polyester.
Dependencies are inferred from the claim text.