CELLULOSE ACETATE FILM, A POLARIZER CONTAINING THE SAME, AND A LIQUID CRYSTAL DISPLAY DEVICE CONTAINING THE CELLULOSE ACETATE FILM CAPABLE OF IMPROVING OPTICAL ANISOTROPY PROPERTIES BY INCLUDING AN OLIGOMER TYPE RETARDATION DEPRESSANT

摘要

PURPOSE: A cellulose acetate film, a polarizer containing the same, and a liquid crystal display device containing the cellulose acetate film are provided to reduce haze generation after unveiling and leakage problem of the depressant.;CONSTITUTION: A cellulose acetate film contains a retardation depressant. The retardation depressant has an oligomer type which is formed by condensation reaction of divalent carboxy acid and divalent alcohol. The cellulose acetate film satisfies the following equations of 1 - 4. The equation 1: Re(λ)=(nx-ny)×d, the equation 2: Rth(λ)=((nx+ny)/2-nz)×d, the equation 3: 0ΔRe(550)Δ10, |Rth(550)|Δ25, the equation 4: |Re(400)-Re(700)|Δ10, |Rth(400)-Rth(700)|Δ35. In the equation 1-4, Re (λ) is the retardation value in surface direction at wavelength of λ nano meters, Rth(λ) is retardation in thickness direction at the wavelength of λ nano meters, nx is a refractive index of x-axis direction in the film surface, ny indicates the refractive index of y-direction in the film surface, and nz indicates the refractive index of the thickness direction in the film. D is thickness of the film.;COPYRIGHT KIPO 2012