Patent ID: 7270855

Claim:
A method for manufacturing a retardation film comprising a cholesteric layer whose constituent molecules are oriented while having a cholesteric structure, the method comprising: forming an expanded layer by expanding onto an alignment substrate a coating solution that contains a liquid crystalline monomer, a chiral dopant and at least one of a polymerizing agent and a cross-linking agent and has a ratio of the chiral dopant to the liquid crystalline monomer ranging from 5 wt % to 23 wt %; subjecting the expanded layer to a heat treatment so that the liquid crystalline monomer is oriented while having a cholesteric structure; and subjecting the expanded layer to at least one of a polymerization treatment and a cross-linking treatment so as to fix the orientation of the liquid crystalline monomer and form the cholesteric layer of a non-liquid crystalline polymer, wherein the liquid crystalline monomer is at least one selected from the group consisting of: a compound represented by the below formula (4); a compound represented by the below formula (5); a compound represented by the below formula (6); a compound represented by the below formula (7); a compound represented by the below formula (8); a compound represented by the below formula (9); a compound represented by the below formula (10); a compound represented by the below formula (11); a compound represented by the below formula (12); a compound represented by the below formula (13); a compound represented by the below formula (14); a compound represented by the below formula (15); a compound represented by the below formula (16); a compound represented by the below formula (17); a compound represented by the below formula (18); and a compound represented by the below formula (19), and the chiral dopant is at least one selected from the group consisting of: a compound represented by the below formula (24); a compound represented by the below formula (25); a compound represented by the below formula (26); a compound represented by the below formula (27); a compound represented by the below formula (28); a compound represented by the below formula (29); a compound represented by the below formula (30); a compound represented by the below formula (31); a compound represented by the below formula (32); a compound represented by the below formula (33); a compound represented by the below formula (34); a compound represented by the below formula (35); a compound represented by the below formula (36); a compound represented by the below formula (37); a compound represented by the below formula (38); a compound represented by the below formula (39); a compound represented by the below formula (40); a compound represented by the below formula (41); a compound represented by the below formula (42); a compound represented by the below formula (43); and a compound represented by the below formula (44):