Electro-optic mirror element and process of making same

• US 9,454,054 B2
• Filed: 11/07/2014
• Issued: 09/27/2016
• Est. Priority Date: 11/18/2013
• Status: Active Grant

• Current Assignee: Magna Mirrors of America Incorporated (Magna International Incorporated)
• Original Assignee: Magna Mirrors of America Incorporated (Magna International Incorporated)
• Inventors: Gallas, Michael L., Habibi, Hamid
• Primary Examiner(s): Davis, Robert B
• Application Number:
  US14/535,741
• Publication Number:
  US 20150140146A1
• Time in Patent Office: 690 Days
• US Class Current: 1/1
• CPC Class Codes: B29D 11/00596 Mirrors
• CPC Class Codes: B29K 2063/00 Use of EP, i.e. epoxy resins or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2105/20 Inserts
• CPC Class Codes: B29K 2995/0005 Conductive
• CPC Class Codes: B29K 2995/003 Reflective
• CPC Class Codes: B32B 17/10917 between two pre-positioned glass layers
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: G02F 1/1341 Filling or closing of cells
• CPC Class Codes: G02F 1/157 Structural association of cells with optical devices, e.g. reflectors or illuminating devices
• CPC Class Codes: G02F 1/161 Gaskets; Spacers; Sealing of cells; Filling or closing of cells

Abstract

A system for filling a variable reflectance vehicular electro-optic element assembly (such as for a rearview mirror assembly) includes a front substrate, a rear substrate and a perimeter seal disposed between the front and rear substrates. The perimeter seal spaces the front and rear substrates apart and forms an interpane cavity therebetween. The perimeter seal has a gap between terminal ends of the perimeter seal to provide a fill port for the mirror reflective element assembly when the front and rear substrates are mated together. The fill port allows an electro-optic medium to flow therethrough during the filling process. During the filling process, the front and rear substrates are fixtured in a chamber with the fill port disposed at an upper portion of the front and rear substrates, with the filling process being one of (i) a gravity feed filling process and (ii) a pressurized filling process.

Claims

1. A process for filling a variable reflectance vehicular electro-optic rearview mirror reflective element assembly, said filling process comprising:

providing an unfilled mirror cell comprising a front substrate and a rear substrate joined by a perimeter seal;

wherein said front substrate has a first surface that generally faces a driver of a vehicle equipped with a mirror assembly that incorporates said rearview mirror reflective element assembly;

said front substrate having a second surface opposite said first surface, wherein said second surface of said front substrate has a transparent electrically conductive coating disposed thereat;

wherein said rear substrate has a third surface and a fourth surface, wherein said third surface has a conductive coating disposed thereat;

wherein said perimeter seal is disposed between said front and rear substrates, said perimeter seal spacing said front and rear substrates apart and forming an interpane cavity therebetween, wherein said perimeter seal has a gap between terminal ends of said perimeter seal to provide a fill port for said unfilled mirror cell when said front and rear substrates are joined together;

said fill port allowing an electro-optic fluid to flow therethrough during the filling process;

wherein, during the filling process, said unfilled mirror cell is fixtured in a vacuum chamber and oriented with said fill port disposed at an upper portion of said unfilled mirror cell;

wherein, during the filling process, the vacuum chamber is evacuated placing said unfilled mirror cell under negative pressure with no pressure differential between said interpane cavity and the negative pressure of the vacuum chamber;

wherein, during the filling process, a filling element is disposed in the vacuum chamber at said fill port, wherein said filling element comprises (i) a fluid reservoir that receives electro-optic fluid and (ii) a channel that provides fluid communication between said fluid reservoir and said fill port;

wherein, during the filling process, a compressible sealing element having a passageway therethrough is disposed between said filling element and said unfilled mirror cell;

wherein, during the filling process, said filling element substantially seals at said unfilled mirror cell around said fill port via said compressible sealing element;

wherein, during the filling process, electro-optic fluid flows from a reservoir through said channel of said filling element and through said passageway of said compressible sealing element and through said fill port of said unfilled mirror cell to fill said interpane cavity with said electro-optic fluid;

wherein, during the filling process, the electro-optic fluid flows through said fill port to fill said interpane cavity via one of (i) gravity feed and (ii) pressurized filling;

wherein, during the filling process, said interpane cavity is filled with said electro-optic fluid without use of beads disposed in said interpane cavity; and

wherein, after said interpane cavity is filled with said electro-optic fluid and while the filled mirror cell is still in the vacuum chamber and under negative pressure, said filling element and said compressible sealing element are removed from the filled mirror cell, and said fill port is plugged.

2. The filling process of claim 1, wherein said electro-optic fluid comprises an electrochromic fluid.

3. The filling process of claim 1, wherein, during the filling process, the electro-optic fluid flows through said fill port to fill said interpane cavity via gravity feed.

4. The filling process of claim 3, wherein said unfilled mirror cell is fixtured with said fill port at an upper region of said mirror cell.

5. The filling process of claim 4, wherein said compressible sealing element comprises a compressible ring having said passageway therethrough and wherein, during the filling process, said passageway is generally aligned between said channel and said fill port.

6. The filling process of claim 1, wherein said filling element comprises polytetrafluoroethylene (PTFE).

7. The filling process of claim 1, wherein, during the filling process, the electro-optic fluid flows through said fill port to fill said interpane cavity via pressurized filling.

8. The filling process of claim 7, wherein said filling element comprises (i) a tube port that receives a tube that provides pressurized electro-optic fluid and (ii) a channel that provides fluid communication between said tube port and said fill port.

9. The filling process of claim 8, wherein said compressible sealing element comprises a compressible ring having said passageway therethrough and wherein, during the filling process, said passageway is generally aligned between said channel and said fill port.

10. The filling process of claim 8, wherein said filling element comprises polytetrafluoroethylene (PTFE).

11. A filling process for filling a variable reflectance vehicular electro-optic rearview mirror reflective element assembly, said filling process comprising:

providing an unfilled mirror cell comprising a front substrate and a rear substrate joined by a perimeter seal;

wherein said front substrate has a first surface that generally faces a driver of a vehicle equipped with a mirror assembly that incorporates said rearview mirror reflective element assembly;

said front substrate having a second surface opposite said first surface, wherein said second surface of said front substrate has a transparent electrically conductive coating disposed thereat;

wherein said rear substrate has a third surface and a fourth surface, wherein said third surface has a conductive coating disposed thereat;

wherein said perimeter seal is disposed between said front and rear substrates, said perimeter seal spacing said front and rear substrates apart and forming an interpane cavity therebetween, wherein said perimeter seal has a gap between terminal ends of said perimeter seal to provide a fill port for said mirror reflective element assembly when said front and rear substrates are joined together;

said fill port allowing an electro-optic fluid to flow therethrough during the filling process;

wherein, during the filling process, said unfilled mirror cell is fixtured in a vacuum chamber and oriented with said fill port disposed at an upper portion of said unfilled mirror cell;

wherein, during the filling process, the vacuum chamber is evacuated placing said unfilled mirror cell under negative pressure with no pressure differential between said interpane cavity and the negative pressure of the vacuum chamber;

wherein, during the filling process, a filling element is disposed in the vacuum chamber at said fill port, wherein said filling element comprises (i) a fluid receiver that receives electro-optic fluid and (ii) a channel that provides fluid communication between said fluid receiver and said fill port;

wherein, during the filling process, a compressible sealing element having a passageway therethrough is disposed between said filling element and said unfilled mirror cell;

wherein, during the filling process, said filling element substantially seals at said unfilled mirror cell around said fill port via said compressible sealing element;

wherein said compressible sealing element comprises a compressible ring having a passageway therethrough with said passageway generally aligned between said channel and said fill port;

wherein, during the filling process, electro-optic fluid flows from a reservoir through said channel of said filling element and through said passageway of said compressible sealing element and through said fill port of said unfilled mirror cell to fill said interpane cavity with said electro-optic fluid;

wherein, during the filling process, the electro-optic fluid flows through said fill port to fill said interpane cavity via one of (i) gravity feed and (ii) pressurized filling;

wherein, during the filling process, said interpane cavity is filled with said electro-optic fluid without use of beads disposed in said interpane cavity; and

wherein, after said interpane cavity is filled with said electro-optic fluid and while the filled mirror cell is still in the vacuum chamber and under negative pressure, said filling element and said compressible sealing element are removed from the filled mirror cell, and said fill port is plugged.

12. The filling process of claim 11, wherein said electro-optic fluid comprises an electrochromic fluid.

13. The filling process of claim 11, wherein said unfilled mirror cell is fixtured with said fill port at an upper region of said mirror cell.

14. The filling process of claim 11, wherein said filling element comprises polytetrafluoroethylene (PTFE).

15. A filling process for filling a variable reflectance vehicular electro-optic rearview mirror reflective element assembly, said filling process comprising:

providing an unfilled mirror cell comprising a front substrate and a rear substrate joined by a perimeter seal;

wherein said front substrate has a first surface that generally faces a driver of a vehicle equipped with a mirror assembly that incorporates said rearview mirror reflective element assembly;

said front substrate having a second surface opposite said first surface, wherein said second surface of said front substrate has a transparent electrically conductive coating disposed thereat;

wherein said rear substrate has a third surface and a fourth surface, wherein said third surface has a conductive coating disposed thereat;

wherein said perimeter seal is disposed between said front and rear substrates, said perimeter seal spacing said front and rear substrates apart and forming an interpane cavity therebetween, wherein said perimeter seal has a gap between terminal ends of said perimeter seal to provide a fill port for said mirror cell when said front and rear substrates are joined together;

said fill port allowing an electrochromic fluid to flow therethrough during the filling process;

wherein, during the filling process, said unfilled mirror cell is fixtured in a vacuum chamber and oriented with said fill port disposed at an upper portion of said unfilled mirror cell;

wherein, during the filling process, the vacuum chamber is evacuated placing said unfilled mirror cell under negative pressure with no pressure differential between said interpane cavity and the negative pressure of the vacuum chamber;

wherein said unfilled mirror cell is fixtured with said fill port at an upper region of said mirror cell;

wherein, during the filling process, a filling element is disposed in the vacuum chamber at said fill port, wherein said filling element comprises (i) a fluid receiver that receives electrochromic fluid and (ii) a channel that provides fluid communication between said fluid reservoir and said fill port;

wherein, during the filling process, said filling element substantially seals at said unfilled mirror cell around said fill port via a compressible sealing element that circumscribes said fill port;

wherein, during the filling process, electro-optic fluid flows from a reservoir through said channel of said filling element and through a passageway of said compressible sealing element and through said fill port of said unfilled mirror cell to fill said interpane cavity with said electro-optic fluid;

wherein, during the filling process, the electro-optic fluid flows through said fill port to fill said interpane cavity via one of (i) gravity feed and (ii) pressurized filling;

wherein, during the filling process, said interpane cavity is filled with said electro-optic fluid without use of beads disposed in said interpane cavity; and

wherein, after said interpane cavity is filled with said electro-optic fluid and while the filled mirror cell is still in the vacuum chamber and under negative pressure, said filling element and said compressible sealing element are removed from the filled mirror cell, and said fill port is plugged.

16. The filling process of claim 15, wherein, during the filling process, the electro-optic fluid flows through said fill port to fill said interpane cavity via gravity feed.

17. The filling process of claim 15, wherein, during the filling process, the electro-optic fluid flows through said fill port to fill said interpane cavity via pressurized filling, and wherein said fluid receiver receives a tube that provides pressurized electrochromic fluid.

18. The filling process of claim 15, wherein said filling element comprises polytetrafluoroethylene (PTFE).