Optical laminate and elliptic polarizer containing the same

Abstract

To provide an optical laminate that hardly gets strained when curved, and has high flexibility and a superior oblique reflectance, and is suitable to a flexible display.SOLUTION: There is provided an optical laminate 100 that includes a retardation film 1, a polarizer 3, and a transparent protective film 5 in this order. The retardation film includes a base material film 11 which has a water-vapor permeability of 100 g / m2 / 24 hours, and a liquid crystal cured film which is formed on the base film to a thickness of 0.5 to 3 μm, and satisfies Re(450) / Re(550)≤1.00 (1) and 1.00≤Re(650) / Re(550) (2) with a single layer, wherein the transparent protective film has a total light transmittance of 90% or larger and a transmittance of 30 to 380 nm, and the retardation film, the polarizer, and the transparent protective film are contiguous across adhesion layers 2, 4.SELECTED DRAWING: Figure 1

Claims

1. An optical laminate comprising a phase difference film, a polarizer, and a transparent protective film in this order, The phase difference film is 100 g / m² ２ A base film having a moisture permeability of 24 hours or more, and a film formed on the base film having a thickness of 0.5 μm or more and 3 μm or less, and relating to the following formulas (1) and (2): Re(450) / Re(550)≦1.00 (1) 1.00≦Re(650) / Re(550) (2) [In the formula, Re(λ) represents the in-plane phase difference value at wavelength λ.] It comprises a liquid crystal curing film that fills the area in a single layer, The aforementioned liquid crystal curing film is given by the following formula (X): [In formula (X), Ar represents a divalent group having an aromatic group which may have substituents, and the aromatic group contains at least one of a nitrogen atom, an oxygen atom, and a sulfur atom.] G1 and G2 each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group, where the hydrogen atoms in the divalent aromatic group or divalent alicyclic hydrocarbon group may be substituted with halogen atoms, C1-C4 alkyl groups, C1-C4 fluoroalkyl groups, C1-C4 alkoxy groups, cyano groups, or nitro groups, and the carbon atoms constituting the divalent aromatic group or divalent alicyclic hydrocarbon group may be substituted with oxygen atoms, sulfur atoms, or nitrogen atoms. L1, L2, B1, and B2 are each independently single or divalent linking groups. k and l each represent integers from 0 to 3 independently, satisfying the relationship 1 ≤ k + l, where 2 ≤ k + l. B1 and B2, and G1 and G2, may be identical or different from each other. E1 and E2 each independently represent an alkanediyl group having 1 to 17 carbon atoms, where the hydrogen atoms in the alkanediyl group may be substituted with halogen atoms, and the -CH2- in the alkanediyl group may be substituted with -O-, -S-, or -C(=O)-. P1 and P2 independently represent a polymerizable group or a hydrogen atom, and at least one of them is a polymerizable group. Formed from a cured product of a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound represented by, The polarizer is composed of a polyvinyl alcohol-based resin film containing a dichroic dye. The transparent protective film has a total light transmittance of 90% or more and a 380nm transmittance of 30% or less. An optical laminate in which the phase difference film, the polarizer, and the transparent protective film are adjacent to each other with an adhesive layer in between.

2. The optical laminate according to claim 1, wherein the substrate film has a total light transmittance of 90% or more, and the absolute value of the phase difference value Rth(550) in the thickness direction for light at 550 nm is 5 nm or less.

3. The optical laminate according to claim 1 or 2, wherein the phase difference film has a photo-alignment film with a thickness of 10 nm to 1000 nm between the base film and the liquid crystal cured film.

4. The aforementioned liquid crystal curing film is given by the following formula (3): 100 nm ≤ Re(550) ≤ 170 nm (3) [In the formula, Re(λ) represents the in-plane phase difference value at wavelength λ.] An optical laminate according to any one of claims 1 to 3, satisfying the requirements.

5. The transparent protective film is 100 g / m². ２ An optical laminate according to any one of claims 1 to 4, having a moisture permeability of 24 hours or more.

6. The optical laminate according to any one of claims 1 to 5, wherein the adhesive layer is a layer formed from a dry-solidifying adhesive.

7. The optical laminate according to claim 6, wherein the drying and solidifying adhesive contains polyvinyl alcohol.

8. The optical laminate according to any one of claims 1 to 7, wherein the phase difference film is in contact with the adhesive layer that bonds the phase difference film and the polarizer on the liquid crystal curing film side.

9. An optical laminate roll obtained by winding up an optical laminate according to any one of claims 1 to 8.

10. An elliptic polarizer comprising an optical laminate according to any one of claims 1 to 8.

11. An organic EL display device comprising the elliptic polarizer described in claim 10.

12. A flexible image display device comprising the elliptical polarizing plate described in claim 10.

13. The flexible image display device according to claim 12, further comprising a window and a touch sensor.

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