Method for manufacturing retardation film, retardation film, polarizing plate, and liquid crystal display
First Claim
1. A retardation film manufactured by the manufacturing method comprisingfeeding a thermoplastic resin film;
- andstretching the thermoplastic resin film while adjusting stretching ratio α
[%], temperature β
[°
C.], and stretching speed γ
[%/min] so that the following formulas (1) and (2) are satisfied when the thermoplastic resin film is stretched at the stretching ratio α
[%], the temperature β
[°
C.], and the stretching speed γ
[%/min];
Z>
X
(1)
(X×
100/k)×
0.2<
(Y−
X)×
100/k
(2)wherein X represents yield stress [MPa] in a stress-strain curve, Y represents stress [MPa] in the stress-strain curve when the film is further stretched from the yield stress by k [%] which is an amount of strain until the yield stress, and Z represents stress [MPa] in the stress-strain curve when the film is stretched to α
[%];
wherein the retardation film has in-plane retardation Re whose unevenness in a transverse direction is 10 nm or less, and thickness direction retardation Rth whose unevenness in the transverse direction is 20 nm or less.
1 Assignment
0 Petitions
Accused Products
Abstract
A retardation film is manufactured by stretching a thermoplastic resin film while adjusting stretching ratio α [%], temperature β [° C.], and stretching speed γ [%/min] so that the following formulas (1) and (2) are satisfied when the thermoplastic resin film is stretched at the stretching ratio α [%], the temperature β [° C.], and the stretching speed γ [%/min], therefore, stretching unevenness can be prevented:
Z>X (1)
(X×100/k)×0.2<(Y−X)×100/k (2)
here X represents yield stress [MPa] in a stress-strain curve, Y represents stress [MPa] in the stress-strain curve when the film is further stretched from the yield stress by k [%] which is the amount of strain until the yield stress, and Z represents stress [MPa] in the stress-strain curve when the film is stretched to α [%].
5 Citations
7 Claims
-
1. A retardation film manufactured by the manufacturing method comprising
feeding a thermoplastic resin film; - and
stretching the thermoplastic resin film while adjusting stretching ratio α
[%], temperature β
[°
C.], and stretching speed γ
[%/min] so that the following formulas (1) and (2) are satisfied when the thermoplastic resin film is stretched at the stretching ratio α
[%], the temperature β
[°
C.], and the stretching speed γ
[%/min];
Z>
X
(1)
(X×
100/k)×
0.2<
(Y−
X)×
100/k
(2)wherein X represents yield stress [MPa] in a stress-strain curve, Y represents stress [MPa] in the stress-strain curve when the film is further stretched from the yield stress by k [%] which is an amount of strain until the yield stress, and Z represents stress [MPa] in the stress-strain curve when the film is stretched to α
[%];wherein the retardation film has in-plane retardation Re whose unevenness in a transverse direction is 10 nm or less, and thickness direction retardation Rth whose unevenness in the transverse direction is 20 nm or less. - View Dependent Claims (2, 3, 4, 5, 6, 7)
- and
Specification