| 摘要 |
PROBLEM TO BE SOLVED: To enable the uniform and high-grade display in the entire area of a display region by using a thermoplastic resin film formed in such a manner that the front surface layer having the relatively high glass transition point as compared with the central part in the thickness direction attains a uniform thickness. SOLUTION: This phase difference plate is so formed that the front surface layer having the relatively high glass transition point Tg attains the uniform thickness. In this case, the retardation value depends on the retardation value of the front surface layer having the high Tg and, thereafter, the retardation value is made uniform. An arbitrary low-mol.wt. compd. which has the high compatibility with the thermoplastic resin to be used and has the b. p. in a range of T-50 deg.C to 5+100 deg.C when the extrusion temp. is defined as T deg.C is used as a plasticizer. An example of the plasticizer that can be used includes phthalate plasticizers, etc. Further, the plasticizer is compounded at a ratio of 1 to 10 pts.wt. per 100 pts.wt. thermoplastic resin. If the ratio thereof is below 1 pt.wt., the retardation value is not uniform and the resistance to heat is insufficient if the ratio is >=10 pts.wt. |
