LAMINATED BODY

• US 20150041051A1
• Filed: 08/08/2014
• Published: 02/12/2015
• Est. Priority Date: 08/09/2013
• Status: Active Grant

• Current Assignee: Sumitomo Chemical Company Limited
• Original Assignee: Sumitomo Chemical Company Limited
• Inventors: KOBAYASHI, Tadahiro
• Granted Patent: US 10,353,128 B2
• Time in Patent Office: Days
• US Class Current: 156/241
• CPC Class Codes: B32B 2457/20 Displays, e.g. liquid crystal displays, plasma displays
• CPC Class Codes: C09K 2323/00 Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition
• CPC Class Codes: C09K 2323/03 Viewing layer characterised by chemical composition
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• CPC Class Codes: G02B 5/3033 in the form of a thin sheet or foil, e.g. Polaroid
• 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

Abstract

Laminated body including a substrate and an optically anisotropic layer. This layer satisfies the following expressions (1), (2), and (3): Δn₅₀(450)/Δn₅₀(550)≦1.00 (1), and 1.00≦Δn₅₀(650)/Δn₅₀(550) (2) wherein Δn₅₀(450), Δn₅₀(550) and Δn₅₀(650) represent the respective birefringences of the layer that are derived from retardation values of the laminated body that are obtained by measuring the laminated body at wavelengths of 450 nm, 550 nm and 650 nm in the state of inclining the fast axis of the layer at an angle of 50 degrees to act as an inclined central axis; and n_z>n_x≅n_y (3) wherein n_x and n_y represent the respective refractive indexes of the substrate in directions parallel with the plane of the substrate, these directions being orthogonal to each other, and n_z represents the refractive index of the substrate in a direction orthogonal to each of the directions about n_x and n_y.

Claims

1. A laminated body, comprising a substrate and an optically anisotropic layer, the layer satisfying the following expressions (1), (2), and (3):

Δ

n₅₀(450)/Δ

n₅₀(550)≦

1.00 

 

(1), and

1.00≦

Δ

n₅₀(650)/Δ

n₅₀(550) 

 

(2)

wherein Δ

n₅₀(450), Δ

n₅₀(550) and Δ

n₅₀(650) represent the respective birefringences of the optically anisotropic layer that are derived from retardation values of the laminated body that are obtained by measuring the laminated body at wavelengths of 450 nm, 550 nm and 650 nm in the state of inclining the fast axis of the optically anisotropic layer at an angle of 50 degrees to act as an inclined central axis, and

n_z>

n_x≅

n_y 

 

(3)

wherein n_x and n_y represent the respective refractive indexes of the substrate in directions parallel with the plane of the substrate, these directions being orthogonal to each other, and n_z represents the refractive index of the substrate in a direction orthogonal to each of the directions about n_x and n_y.

2. The laminated body according to claim 1, wherein the optically anisotropic layer comprises a composition comprising a polymerizable liquid crystal compound and a photopolymerization initiator.

3. The laminated body according to claim 1, comprising an oriented film layer between the substrate and the optically anisotropic layer, the oriented film layer comprising at least one selected from the group consisting of polyimides, polyamides and polyamic acids.

4. The laminated body according to claim 3, wherein the oriented film layer has an orientation regulating force for orienting a polymerizable liquid crystal compound vertically.

5. The laminated body according to claim 1, wherein in the case of adopting a structure in which a polarizing plate (A), the laminated body according to any one of claims 1 to 4, and a polarizing plate (B) are stacked onto each other in this order, making the absorption axis of the polarizing plate (A) orthogonal to that of the polarizing plate (B), and further adopting any one of the following cases (a) and (b):

(a) in a case where the substrate, which partially constitutes the laminated body, has a slow axis inside the plane thereof, this substrate is arranged at the polarizing plate (B) side of the structure and further the substrate is stacked to make the slow axis of the substrate parallel with the absorption axis of the polarizing plate (B), and

(b) in a case where the substrate, which partially constitutes the laminated body, has no slow axis inside the plane thereof, this substrate is arranged at the polarizing plate (B) side of the structure,

the transmittance T at wavelengths of 550 nm of the structure, this transmittance being obtained when light is radiated into the structure from the polarizing plate (B) side thereof and then the resultant transmitted light is detected from the polarizing plate (A) side thereof, satisfies the following expression (D);

0.000<

T<

0.005 

 

(D)

wherein the transmittance T is a value relative to the transmittance of a stacked body of the polarizing plates (A) and (B) that is obtained when the polarizing plates (A) and (B) are arranged to make the respective axes thereof parallel with each other, this transmittance being regarded as 100%.

6. The laminated body according to claim 1, wherein the substrate satisfies the following expression (4):

n_x>

n_y≅

n_z 

 

(4)

wherein n_x, n_y and n_z have the same meanings as defined above.

7. The laminated body according to claim 1, wherein the substrate satisfies the following expressions (5) and (6):

Δ

n(450)/Δ

n(550)≧

1.00 

 

(5), and

1.00≧

Δ

n(650)/Δ

n(550) 

 

(6)

wherein Δ

n(450), Δ

n(550) and Δ

n(650) represent the respective birefringences of the substrate that are derived from the front retardation values of the laminated body that are obtained by measuring the laminated body at wavelengths of 450 nm, 550 nm, and 650 nm.

8. The laminated body according to claim 1, wherein the substrate satisfies the following expressions (7) and (8):

Δ

n(450)/Δ

n(550)≦

1.00 

 

(7), and

1.00≦

Δ

n(650)/Δ

n(550) 

 

(8)

wherein Δ

n(450), Δ

n(550) and Δ

n(650) have the same meanings as defined above.

9. The laminated body according to claim 2, wherein the polymerizable liquid crystal compound is a compound represented by the following formula (A):

10. A method for producing a laminated body, comprising the following steps (a1) and (a2):

step (a1) of applying a composition comprising a polymerizable liquid crystal compound represented by the formula (A) in claim 9 to a substrate; and

step (a2) of drying the applied composition, and radiating light to the composition to cure the composition.

11. A method for producing a laminated body, comprising the following steps (b1), (b2) and (b3):

step (b1) of applying an orienting polymer to a substrate to form an oriented film layer;

step (b2) of applying a composition comprising a polymerizable liquid crystal compound represented by the formula (A) in claim 9 onto the oriented film layer; and

step (b3) of drying the applied composition, and radiating light to the composition to cure the composition.

12. A polarizing plate, comprising the laminated body recited in claim 1.

13. A display device, comprising the laminated body recited in claim 1.

14. A laminated-body-producing method, comprising transferring the optically anisotropic layer of the laminated body recited in claim 1 onto a transfer-receiving substrate to interpose an adhesive between the optically anisotropic layer and the transfer-receiving substrate, thereby yielding a second laminated body comprising the transfer-receiving substrate, a layer of the adhesive, and the optically anisotropic layer.

15. A laminated body, comprising a transfer-receiving substrate, and an optically anisotropic layer, the optically anisotropic layer satisfying the following expressions (1), (2) and (3):

Δ

n₅₀(450)/Δ

n₅₀(550)≦

1.00 

 

(1), and

1.00≦

Δ

n₅₀(650)/Δ

n₅₀(550) 

 

(2)

wherein Δ

n₅₀(450), Δ

n₅₀₀(550) and Δ

n₅₀(650) represent the respective birefringences of the optically anisotropic layer that are derived from retardation values of the laminated body that are obtained by measuring the laminated body at wavelengths of 450 nm, 550 nm and 650 nm in the state of inclining the fast axis of the optically anisotropic layer at an angle of 50 degrees to act as an inclined central axis, and

n_z>

n_x≅

n_y 

 

(3)

wherein n_x and n_y represent the respective refractive indexes of the substrate in directions parallel with the plane of the substrate, these directions being orthogonal to each other, and n_z represents the refractive index of the substrate in a direction orthogonal to each of the directions about n_x and n_y.