Granted Patent B2

US 12,548,477 · App. 17/615,426 · Granted Feb 10, 2026

Inventors: Shotaro Nishio (Tsuruga, JP); Kiwamu Kawai (Tsuruga, JP); Akira Shimizu (Tsuruga, JP)

Assignee: TOYOBO CO., LTD.

G09F9/301B32B27/36G02B5/3016G02B5/305G02B5/3083H10K59/8791H10K59/8793H10K59/879

Abstract

Claims (26)

1 . A polarizing plate for a foldable display, comprising:

a polarizer; and

a polarizer protective film formed of a polyester film laminated on at least one surface of the polarizer,

wherein the polyester film is a biaxially stretched polyethylene terephthalate film and satisfies the following conditions:

(1) a refractive index in a bending direction is from 1.590 to 1.600;

(2) a refractive index in a folding portion direction is from 1.680 to 1.695;

(3) a refractive index in a thickness direction is 1.505 or less; and

(4) a density is 1.380 g/cm 3 or more,

wherein the bending direction refers to a direction orthogonal to a folding portion of the polyester film at a time when the polyester film is folded.

2 . The polarizing plate for a foldable display according to claim 1 , wherein the polarizer has a thickness of 12 μm or less.

3 . The polarizing plate for a foldable display according to claim 2 , wherein the polarizer is formed of a polymerizable liquid crystal compound and a dichroic dye.

4 . The polarizing plate for a foldable display according to claim 1 , wherein the polarizer is formed of a polymerizable liquid crystal compound and a dichroic dye.

5 . A foldable display comprising the polarizing plate for a foldable display of claim 1 .

6 . A foldable display comprising the polarizing plate for a foldable display of claim 2 .

7 . A foldable display comprising the polarizing plate for a foldable display of claim 3 .

8 . A circularly polarizing plate for a foldable display, comprising: the polarizing plate for a foldable display of claim 1 ; and

a retardation layer formed on at least one surface of the polarizing plate.

9 . The circularly polarizing plate for a foldable display according to claim 8 , wherein the circularly polarizing plate is free of any self-supporting film or further comprises only one self-supporting film other than the polyester film.

10 . The circularly polarizing plate for a foldable display according to claim 9 , wherein the polarizer has a thickness of 12 μm or less.

11 . The circularly polarizing plate for a foldable display according to claim 10 , wherein the polarizer is formed of a polymerizable liquid crystal compound and a dichroic dye.

12 . The circularly polarizing plate for a foldable display according to claim 9 , wherein the polarizer is formed of a polymerizable liquid crystal compound and a dichroic dye.

13 . The circularly polarizing plate for a foldable display according to claim 8 , wherein the polarizer has a thickness of 12 μm or less.

14 . The circularly polarizing plate for a foldable display according to claim 8 , wherein the polarizer is formed of a polymerizable liquid crystal compound and a dichroic dye.

15 . A foldable display comprising the circularly polarizing plate for a foldable display of claim 8 , wherein the retardation layer contains a liquid crystal compound.

16 . A foldable display comprising the circularly polarizing plate for a foldable display of claim 9 , wherein the retardation layer contains a liquid crystal compound.

17 . A foldable display comprising the circularly polarizing plate for a foldable display of claim 10 , wherein the retardation layer contains a liquid crystal compound.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (276)