| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a biaxial birefringence film which can form a liquid crystal display device or the like which excels in optical compensation performance, and which has a negative birefringence characteristics, while it realizes the thinness of a retardation film, laminated polarizing plate and a liquid crystal display device or the like. <P>SOLUTION: A solution which has at least one kind of polymer chosen from the group consists of polyamide, polyimide, polyester, polyetherketone, polyamideimide and polyetherimide dissolved in a solvent is coated on a base material. This birefringence film is formed after drying by using a base material which goes through a dimensional change in the process to be made into a film. Its birefringence is within the range of 0.0005 to 0.5, and also this birefringence satisfies all the formulas from (1) to (3): nx, ny is a main refraction factor in a flat surface of a film, nz is a refractive index of the thickness direction of a film, and (d) is the thickness of a film. Where, the following inequalities are satisfied: nx>ny>nz (1) 3nm≤(nx-ny)×d (2) (nx-nz)/(nx-ny)>1 (3). <P>COPYRIGHT: (C)2004,JPO |
