Phase difference plate comprising polymer film containing compound having rod-shaped molecular structure

• US 20090163703A1
• Filed: 02/13/2009
• Published: 06/25/2009
• Est. Priority Date: 03/14/2001
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Kawanishi, Hiroyuki, Fujii, Takamichi, Sata, Hiroaki, Takeuchi, Hiroshi
• Granted Patent: US 7,943,210 B2
• Time in Patent Office: Days
• US Class Current: 536/58
• CPC Class Codes: C09K 2323/02 Alignment layer characterised by chemical composition
• CPC Class Codes: C09K 2323/03 Viewing layer characterised by chemical composition
• CPC Class Codes: C09K 2323/035 Ester polymer, e.g. polycarbonate, polyacrylate or polyester
• CPC Class Codes: G02B 5/3083 Birefringent or phase retarding elements G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n

Abstract

A phase difference plate which comprises one sheet of polymer film containing a compound having a rod-shaped molecular structure and exhibiting a maximum absorption wavelength (λmax) of less than 250 nm in an ultraviolet spectrum of its solution and which exhibits a retardation value as measured at a wavelength of 450 nm (Re450) of 60 to 135 nm and a retardation value as measured at a wavelength of 590 nm (Re590) of 100 to 170 nm, where the relationship: Re590−Re450≧2 nm is satisfied. The phase difference plate functions as a λ/4 plate.

Claims

1. A phase difference plate comprising a cellulose ester film which contains a compound represented by the following formula (I):

Ar¹-L¹-Ar² 

 

(I)

in which each of Ar¹ and Ar² is independently phenyl or phenyl substituted with an alkyl group; and

L¹ is —

O—

CO-alkylene-CO—

O—

or —

CO—

O-alkylene-O—

CO—

.

2. The phase difference plate as defined in claim 1, wherein the compound represented by the formula (I) exhibits a maximum absorption wavelength (λ

max) of shorter than 250 nm in an ultraviolet absorption spectrum measured in a form of a solution of the compound.

3. The phase difference plate as defined in claim 1, wherein each of Ar¹ and Ar² is independently phenyl substituted with an alkyl group.

4. The phase difference plate as defined in claim 3, wherein the alkyl group is selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, heptyl and octyl.

5. The phase difference plate as defined in claim 1, wherein the alkylene group contained in L¹ has a chain structure.

6. The phase difference plate as defined in claim 1, wherein the alkylene group contained in L¹ has 1 to 20 carbon atoms.

7. The phase difference plate as defined in claim 6, wherein the alkylene group contained in L¹ has 1 to 10 carbon atoms.

8. The phase difference plate as defined in claim 7, wherein the alkylene group contained in L¹ has 1 to 6 carbon atoms.

9. The phase difference plate as defined in claim 1, wherein the cellulose ester film contains the compound represented by the formula (I) in an amount of 0.1 to 30 wt. % based on the amount of cellulose ester contained in the cellulose ester film.

10. A cellulose ester film containing a compound represented by the following formula (I):

Ar¹-L¹-Ar² 

 

(I)

in which each of Ar¹ and Ar² is independently phenyl or phenyl substituted with an alkyl group; and

L¹ is —

O—

CO-alkylene-CO—

O—

or —

CO—

O-alkylene-O—

CO—

.