JP2006221134A5 - - Google Patents

Claims (25)

  A retardation film, wherein a material having refractive index anisotropy is permeated into a polymer film.   A retardation film in which a material having refractive index anisotropy is contained in a polymer film, wherein the material having refractive index anisotropy has a concentration gradient in the thickness direction of the polymer film. A retardation film, wherein the density gradient changes continuously. The retardation film according to claim 1 , wherein the polymer film has in- plane retardation and / or thickness direction retardation . Material having a refractive index anisotropy, the retardation film according to any one of claims 1 to 3, characterized in that a material having liquid crystallinity. The retardation film according to any one of claims 1 to 4 , wherein the molecular structure of the material having refractive index anisotropy is rod-shaped. The retardation film according to the material having the refractive index anisotropy, any one of claims 1 to 5, characterized in that those having a polymerizable functional group. The retardation film according to any one of claims 1 to 5 wherein the material having refractive index anisotropy, characterized in that those that do not have a polymerizable functional group and having a polymerizable functional group. The concentration gradient in the thickness direction of the polymer film of the material having refractive index anisotropy is a concentration gradient in which one surface side of the polymer film has a high concentration and decreases toward the other surface side. the retardation film according to any one of claims 1 to 7, characterized in that. The retardation film according to claim 8 , wherein a contact angle of the retardation film with respect to pure water is different between one surface and the other surface. The concentration gradient in the thickness direction of the polymer film of the material having refractive index anisotropy is a concentration gradient in which both surface sides of the polymer film have a high concentration and become a low concentration toward the center. the retardation film according to any one of claims 1 to 7, characterized. And concentration gradient gentle region of material having a refractive index anisotropy, in any one of claims 1 to 10 gradient material having a refractive index anisotropy and having a steep region The retardation film described. The retardation film according to any one of claims 1 to 11, characterized in that it has a region where the material having the refractive index anisotropy is not contained. The refractive index in the slow axis direction in the in-plane direction of the film is nx, the refractive index in the fast axis direction in the in-plane direction of the film is ny, the refractive index in the thickness direction of the film is nz, and the thickness is d. [nm] = {(nx + ny) / 2-nz} of Rth represented by × d when the thickness direction retardation, any of claims 1 to 12 wherein the thickness direction retardation is equal to or is 70~300nm The retardation film of crab. The retardation film according to any one of claims 1 to 13 , wherein a haze value when measured in accordance with JIS-K7105 is 1% or less. The retardation film according to any one of claims 1 to 14 the retardation value in the visible light region, towards the short wavelength side being larger than the long wavelength side of the retardation film. The retardation film according to any one of claims 1 to 14 the retardation value in the visible light region, towards the long wavelength side is equal to or greater than the short wavelength side of the retardation film. 17. The variation in thickness direction retardation (Rth) measured at a wavelength of 550 nm of the retardation film in the film surface direction is within a range of ± 5 nm based on the average value of Rth. 17 . The retardation film described in 1. The retardation film according to any one of claims 1 to 17, wherein the minimum diameter being rollable on 6 inches or less in rolls. The retardation film according to claim 1 in which 18 one or more two retardation films of the monolayer according to the, characterized by comprising adhered to each other. An optical functional film obtained by directly bonding the retardation film according to any one of claims 1 to 19 to an optical functional layer other than the retardation film. Polarizing film retardation film according to any one of claims 1 to 19, characterized by comprising bonded directly with a polarizing layer. A retardation film according to any one of claims 1 to 19 , an optical functional film according to claim 20 , or a polarizing film according to claim 21 is disposed in an optical path. apparatus.   A coating step for applying a coating solution for forming a retardation enhancement region in which a material having refractive index anisotropy is dissolved or dispersed in a solvent is applied to at least one surface of the polymer film, and the coating step is applied. A permeation step for allowing the material having refractive index anisotropy in the retardation enhancement region forming coating solution to penetrate into the polymer film, and the retardation enhancement region forming coating solution applied by the coating step. And a drying step for drying the solvent therein. A method for producing a retardation film. The method for producing a retardation film according to claim 23 , wherein the permeation step is performed during the drying step. After said drying step, method for producing a retardation film according to claim 23 or 24, characterized in that it has a fixing step of fixing the refractive index anisotropic material infiltrated into the polymer film.