Optical stack, method for manufacturing same, and smart window comprising same

Patent metadata

Field	Value
Publication number	US-2025347952-A1
Application number	US-202218729400-A
Country	US
Kind code	A1
Filing date	Dec 16, 2022
Priority date	Jan 21, 2022
Publication date	Nov 13, 2025
Grant date	—

Abstract

The present invention relates to a transmittance-variable optical stack, a method for manufacturing same, and a smart window comprising same, the optical stack comprising: a first polarizing plate including a first functional layer; a first transparent conductive layer formed on one surface of the first polarizing plate; a second polarizing plate including a second functional layer and opposite to the first polarizing plate; a second transparent conductive layer formed on one surface of the second polarizing plate and opposite to the first transparent conductive layer; and a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer, wherein at least one of the first transparent conductive layer and the second transparent conductive layer is formed to come in direct contact with one of the first polarizing plate and the second polarizing plate, and the first functional layer and the second functional layer have a surface pencil hardness of 3B to 6H.

First claim

1 . A variable transmittance optical stack comprising:
a first polarizing plate comprising a first functional layer; a first transparent conductive layer formed on one surface of the first polarizing plate; a second polarizing plate comprising a second functional layer and opposite to the first polarizing plate; a second transparent conductive layer formed on one surface of the second polarizing plate and opposite to the first transparent conductive layer; and a liquid crystal layer provided between the first transparent conductive layer and the second transparent conductive layer, wherein at least one of the first transparent conductive layer and the second transparent conductive layer is formed in direct contact with one of the first polarizing plate and the second polarizing plate, and each of the first and second functional layers has surface pencil hardness ranging from 3B to 6H.

2 . The variable transmittance optical stack of claim 1 , wherein each of the first and second functional layers has surface pencil hardness ranging from HB to 6H.

3 . The variable transmittance optical stack of claim 1 , wherein each of the first and second functional layers comprises at least one of a hard coating layer and a low refractive index layer.

4 . The variable transmittance optical stack of claim 3 , wherein the low refractive index layer comprises one or more selected from a group consisting of SiO 2 , Al 2 O 3 , MgF 2 , CaF 2 , and cryolite.

5 . The variable transmittance optical stack of claim 1 , wherein at least one of the first transparent conductive layer and the second transparent conductive layer is formed in direct contact with one of the first polarizing plate and the second polarizing plate without an additional substrate between the transparent conductive layer and the polarizing plate.

6 . The variable transmittance optical stack of claim 1 , wherein at least one of the first transparent conductive layer and the second transparent conductive layer is formed in direct contact with one of the first polarizing plate and the second polarizing plate with a highly adhesive layer between the transparent conductive layer and the polarizing plate.

7 . The variable transmittance optical stack of claim 1 , wherein at least one of the first transparent conductive layer and the second transparent conductive layer comprises one or more selected from a group consisting of a transparent conductive oxide, metal, carbonaceous material, conductive polymer, conductive ink, and nanowires.

8 . The variable transmittance optical stack of claim 1 , wherein at least one of the first polarizing plate and the second polarizing plate further comprises one or more selected from a group consisting of a protective layer, a retardation matching layer, and a refractive index matching layer.

9 . The variable transmittance optical stack of claim 1 , wherein at least one of the first polarizing plate and the second polarizing plate has a thickness ranging from 30 to 200 μm.

10 . The variable transmittance optical stack of claim 1 , wherein the liquid crystal layer comprises one or more of spacers selected from a group consisting of a ball spacer and a column spacer.

11 . The variable transmittance optical stack of claim 10 , wherein the spacer has a diameter ranging from 1 to 10 μm.

12 . The variable transmittance optical stack of claim 10 , wherein an occupancy area of the spacer in the liquid crystal layer ranges from 0.01% to 10% of the area of the liquid crystal layer.

13 . The variable transmittance optical stack of claim 1 , further comprising:
one or more selected from a group consisting of an alignment film, a pressure-sensitive adhesive/adhesive layer, and an ultraviolet ray absorption layer.

14 . A method for manufacturing the variable transmittance optical stack of any one of claims 1 to 13 .

15 . A smart window comprising the variable transmittance optical stack of any one of claims 1 to 13 .

16 . A transportation means comprising the smart window of claim 15 .

17 . A vehicle in which the smart window of claim 15 is applied to at least one of a front window, a rear window, a side window, a sunroof window, and an inner partition thereof.

18 . A wearable device comprising the smart window of claim 15 .

19 . Windows and doors for a building, the windows and doors comprising the smart window of claim 15 .

Assignees

• Dongwoo Fine Chem Co Ltd

Inventors

• Ahn Hong-Jun
• Kim Dong-Hwi
• Oh Pyoung-Yun

Classifications

• G02F1/13439

  characterised by their electrical, optical, physical properties; materials therefor; method of making · CPC title

• G02F1/13392

  spacers dispersed on the cell substrate, e.g. spherical particles, microfibres · CPC title

• B32B2255/20

  Inorganic coating · CPC title

• B32B2255/205

  Metallic coating · CPC title

• B32B2255/10

  on synthetic resin layer or on natural or synthetic rubber layer · CPC title