CELLULOSE ESTER FILM, AND POLARIZING PLATA AND LIQUID-CRYSTAL DISPLAY DEVICE HAVING THE SAME

摘要

The invention relates to a cellulose ester film, comprising at least one cellulose ester that satisfies the following formulae, 2.2≦X₁+X₂≦2.55, 1.1≦X₁1.5, and 1.05≦X₂≦1.4, which satisfies the following formulae Re(450)/Re(550)1, Re(650)/Re(550)1, Rth(450)/Rth(550)1, and Rth(650)/Rth(550)1, wherein X₁ means a degree of substitution with an acetyl group in the cellulose ester; X₂ means a degree of substitution with a propionyl group and/or a butyryl group in the cellulose ester; Re(λ) means retardation (nm) in plane of the film at a wavelength of λ (nm); and Rth(λ) means retardation (nm) along the thickness direction of the film at a wavelength of λ (nm).