DEVICE FOR REGULATING THE PASSAGE OF ENERGY

• US 20160085108A1
• Filed: 04/09/2014
• Published: 03/24/2016
• Est. Priority Date: 05/08/2013
• Status: Active Grant

• Current Assignee: Merck Patent GmbH (Merck & Co., Inc.)
• Original Assignee: Merck Patent GmbH (Merck & Co., Inc.)
• Inventors: JUNGE, Michael, BEYER, Andreas, PATWAL, Ursula
• Granted Patent: US 10,108,058 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C09K 19/60 Pleochroic dyes
• CPC Class Codes: C09K 2219/13 used in the technical field of thermotropic switches
• CPC Class Codes: G02F 1/13306 Circuit arrangements or driving methods for the control of single liquid crystal cells G02F1/132, G02F1/133382 take precedence
• CPC Class Codes: G02F 1/13324 Circuits comprising solar cells
• CPC Class Codes: G02F 1/1337 Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
• CPC Class Codes: G02F 1/133738 for homogeneous alignment
• CPC Class Codes: G02F 1/13475 in which at least one liquid crystal cell or layer is doped with a pleochroic dye, e.g. GH-LC cell G02F1/13476 takes precedence
• CPC Class Codes: G02F 2203/48 Variable attenuator

Abstract

The present application relates to a device for regulating the passage of energy which is characterised in that it comprises at least two switching layers S(1) and S(2) arranged one behind the other, where the switching layers comprise a liquid-crystalline medium comprising at least one dichroic compound.

Claims

1. Device for regulating the passage of energy through a surface, where the device comprises at least two switching layers S(1) and S(2), each of which comprises a liquid-crystalline medium comprising one or more dichroic compounds, and where the device comprises orientation layers O(1), O(2), O(3) and O(4), where the said switching layers and orientation layers are present in the device in mutually parallel planes in the sequence O(1), S(1), O(2), O(3), S(2), O(4),

where an orientation axis OA(1)* of the molecules of the liquid-crystalline medium of S(1) which are adjacent to O(2) is present in at least one switching state of the device, and an orientation axis OA(2)* of the molecules of the liquid-crystalline medium of S(2) which are adjacent to O(3) is present, and orientation axes OA(1)* and OA(2)* are not parallel to one another and are parallel to the plane of the switching layers.

2. Device according to claim 1, characterised in that it is installed in an opening of a building, a container, a vehicle or another substantially closed space.

3. Device according to claim 1, characterised in that it is electrically switchable.

4. Device according to claim 1, characterised in that it has four electrodes, one of which is installed on each side of each of the two switching layers.

5. Device according to claim 1, characterised in that the switching layers are separately electrically switchable.

6. Device according to claim 1, characterised in that the molecules of the liquid-crystalline medium are aligned vertically to the plane of the switching layers by application of an electric field.

7. Device according to claim 1, characterised in that either both switching layers S(1) and S(2) in the voltage-free switching state have a planar alignment of the molecules of the liquid-crystalline medium, or in that both switching layers S(1) and S(2) in the voltage-free switching state have a homeotropic alignment of the molecules of the liquid-crystalline medium.

8. Device according to claim 1, characterised in that one of the two switching layers S(1) and S(2) in the voltage-free switching state has a homeotropic alignment of the molecules of the liquid-crystalline medium, and the other of the two switching layers S(1) and S(2) in the voltage-free switching state has a planar alignment of the molecules of the liquid-crystalline medium.

9. Device according to claim 1, characterised in that it has a device for the conversion of light energy into electrical energy, preferably a solar cell.

10. Device according to claim 1, characterised in that it has a layer structure in the following sequence, where the layers are preferably directly adjacent to one another:

substrate layer, preferably comprising glass or polymer

electrically conductive transparent layer, preferably ITO layer

orientation layer O(1)

switching layer S(1)

orientation layer O(2)

electrically conductive transparent layer, preferably ITO layer

substrate layer(s), preferably comprising glass or polymer

electrically conductive transparent layer, preferably ITO layer

orientation layer O(3)

switching layer S(2)

orientation layer O(4)

electrically conductive transparent layer, preferably ITO layer

substrate layer, preferably comprising glass or polymer.

11. Device according to claim 1, characterised in that orientation axes OA(1)* and OA(2)* form an angle of 50-90°

, preferably an angle of 70-90°

, and particularly preferably an angle of 85-90°

to one another.

12. Device according to claim 1, characterised in that the at least one switching state of the device in which orientation axes OA(1)* and OA(2)* are not parallel to one another and are parallel to the plane of the switching layers is present in a voltage-free switching state of the device.

13. Device according to claim 1, characterised in that orientation layers O(2) and O(3) are designed in such a way that they each effect different orientation axes of the molecules of the liquid-crystalline medium which is adjacent to the orientation layer.

14. Device according to claim 1, characterised in that layers O(2) and O(3) in the voltage-free switching state effect a planar alignment of the molecules of the liquid-crystalline medium.

15. Device according to claim 1, characterised in that either both orientation layers O(1) and O(2) effect a planar alignment of the molecules of the liquid-crystalline medium, or in that both orientation layers O(1) and O(2) effect a homeotropic alignment of the molecules of the liquid-crystalline medium.

16. Device according to claim 1, characterised in that switching layers S(1) and S(2) have a degree of anisotropy R of 0.7 to 0.9, preferably 0.7 to 0.85, and particularly preferably 0.75 to 0.8.

17. Device according to claim 16, characterised in that at least one of the dichroic compounds is selected from azo compounds, anthraquinones, methine compounds, azomethine compounds, merocyanine compounds, naphthoquinones, tetrazines, perylenes, terrylenes, quaterrylenes, higher rylenes, benzothiadiazoles, diketopyrrolopyrroles, squaraines and pyrromethenes.

18. Device according to claim 1, characterised in that it comprises no polariser.

19. A method for regulating the passage of energy through a substantially energy-transmitting surface into an interior, preferably the passage of energy in the form of sunlight, by a device according to claim 1.

20. Window, characterised in that it comprises a device according to claim 1.