| 主权项 |
1. A retardation film comprising a resin having positive refractive index anisotropy and containing at least one bonding group of a carbonate bond and an ester bond and one or more structural units selected from the group consisting of a structural unit represented by the following general formula (1) and a structural unit represented by the following general formula (2), wherein:
the value of wavelength dispersion (R450/R550) as a ratio of retardation R450 at a wavelength of 450 nm to retardation R550 at a wavelength of 550 nm is more than 0.5 and less than 1.0:(in the general formula (1) and the general formula (2), each of R1 to R3 is independently a direct bond or an alkylene group having a carbon number of from 1 to 4, which may have a substituent, and each of R4 to R9 is independently hydrogen atom, an alkyl group having a carbon number of from 1 to 10, which may have a substituent, an aryl group having a carbon number of from 4 to 10, which may have a substituent, an acyl group having a carbon number of from 1 to 10, which may have a substituent, an alkoxy group having a carbon number of from 1 to 10, which may have a substituent, an aryloxy group having a carbon number of from 1 to 10, which may have a substituent, an acyloxy group having a carbon number of from 1 to 10, which may have a substituent, an amino group which may have a substituent, a vinyl group having a carbon number of from 1 to 10, which may have a substituent, an ethynyl group having a carbon number of from 1 to 10, which may have a substituent, a sulfur atom having a substituent, a silicon atom having a substituent, a halogen atom, a nitro group, or a cyano group, provided that at least two adjacent groups out of R4 to R9 may be linked to each other to form a ring and two substituents R4's, R5's, R6's, R7's, R8's, and R9's may be the same with or different from each other). |
