EL sheet diaphragm and a switch using the same

• US 5,871,088 A
• Filed: 01/16/1998
• Issued: 02/16/1999
• Est. Priority Date: 03/30/1995
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Tanabe, Kouji
• Primary Examiner(s): Friedhofer, Michael A.
• Application Number:
  US08/913,821
• Time in Patent Office: 396 Days
• Field of Search: 29/622, 200/5 R, 200/5 A, 200/512-517, 200/310-317, 313/463, 340/825.81, 345/36, 345/45, 345/76, 345/173, 345/174, 349/69, 365/110, 365/111, 427/66
• US Class Current: 200/514
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 13/785 characterised by the material of the contacts, e.g. conductive polymers
• CPC Class Codes: H01H 2201/032 Conductive polymer; Rubber
• CPC Class Codes: H01H 2209/002 Materials
• CPC Class Codes: H01H 2219/018 Electroluminescent panel
• CPC Class Codes: H01J 1/142 with alkaline-earth metal oxides, or such oxides used in conjunction with reducing agents, as an emissive material
• CPC Class Codes: H01J 9/042 Manufacture, activation of the emissive part
• CPC Class Codes: H05B 33/00 Electroluminescent light sources
• CPC Class Codes: H05B 33/10 Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
• CPC Class Codes: H05B 33/12 Light sources with substantially two-dimensional radiating surfaces
• CPC Class Codes: H05B 33/20 characterised by the chemical or physical composition or the arrangement of the material in which the electroluminescent material is embedded
• CPC Class Codes: H05B 33/22 characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers
• CPC Class Codes: H05B 33/26 characterised by the composition or arrangement of the conductive material used as an electrode
• CPC Class Codes: H05B 33/28 of translucent electrodes

Abstract

An EL sheet diaphragm including a diffusion type EL sheet having a diaphragm portion exhibiting a dome shape and a flange supporting portion disposed about the outer circumference of the diffusion type EL sheet. The diffusion type EL sheet including a transparent film having an upper surface and a lower surface, a transparent electrode layer formed on the lower surface of the transparent film, a light emitting layer formed on the transparent electrode, a dielectric layer formed on the light emitting layer, a rear electrode layer formed on the dielectric layer, and an insulating layer formed on the rear electrode layer. The diffusion type EL sheet emits light from the diaphragm portion of the upper surface of the transparent film. The diffusion type EL sheet bows outwardly in an at-rest state such that the upper surface of the transparent film exhibits a convex shape, and bows inwardly when depressed for operation such that the upper surface of the transparent film exhibits a concave shape.

Claims

1. An EL sheet diaphragm comprising a diffusion type EL sheet having a diaphragm portion exhibiting a dome shape and a flange supporting portion disposed about the outer circumference of said diffusion type EL sheet, said diffusion type EL sheet comprising:

a transparent film having an upper surface and a lower surface,

a transparent electrode layer formed on said lower surface of said transparent film,

a light emitting layer formed on said transparent electrode layer,

a dielectric layer formed on said light emitting layer,

a rear electrode layer formed on said dielectric layer, and

an insulating layer formed on said rear electrode layer,

said diffusion type EL sheet emitting light from at least one selected from the group consisting of (i) the entire area of said EL sheet, (ii) the diaphragm portion only, and (iii) the entire area of said diaphragm portion and an area surrounding said diaphragm portion of said upper surface of said transparent film, said diffusion type EL sheet bowing outwardly in an at-rest state such that said upper surface of said transparent film exhibits a convex shape, said diffusion type EL sheet bowing inwardly when depressed for operation such that said upper surface of said transparent film exhibits a concave shape.

2. An EL sheet diaphragm of claim 1, wherein said transparent electrode layer is formed by printing and drying a paste which is prepared by dispersing conductive powders that have a visible light transmittance in an insulating resin, or in a resin solution containing an insulating resin.

3. An EL sheet diaphragm of claim 2, wherein a binder resin used for said light emitting layer and said dielectric layer is selected from vinylidene fluoride rubber, vinylidene fluoride copolymer rubber, a resin prepared by blending cyanated pullulan and cyanated polyvinyl alcohol, or a resin prepared by blending cyanated cellulose and cyanated polyvinyl alcohol.

4. An EL sheet diaphragm of claim 3, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

5. An EL sheet diaphragm of claim 4, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

6. An EL sheet diaphragm of claim 3, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

7. An EL sheet diaphragm of claim 2, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

8. An EL sheet diaphragm of claim 7, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

9. An EL sheet diaphragm of claim 2, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

10. An EL sheet diaphragm of claim 1, wherein a binder resin used for said light emitting layer and said dielectric layer is selected from a vinylidene fluoride rubber, vinylidene fluoride copolymer rubber, a resin prepared by blending cyanated pullulan and cyanated polyvinyl alcohol, or a resin prepared by blending cyanated cellulose and cyanated polyvinyl alcohol.

11. An EL sheet diaphragm of claim 10, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

12. An EL sheet diaphragm of claim 11, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

13. An EL sheet diaphragm of claim 10, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

14. An EL sheet diaphragm of claim 1, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

15. An EL sheet diaphragm of claim 14, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

16. An EL sheet diaphragm of claim 1, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

17. A switch comprising an EL sheet diaphragm including a diffusion type EL sheet having a diaphragm portion exhibiting a dome shape and a flange supporting portion disposed about the outer circumference of said diffusion type EL sheet, said diffusion type EL sheet comprising:

a transparent film having an upper surface and a lower surface,

a transparent electrode layer formed on said lower surface of said transparent film,

a light emitting layer formed on said transparent electrode layer,

a dielectric layer formed on said light emitting layer,

a rear electrode layer formed on said dielectric layer, and

an insulating layer formed on said rear electrode layer,

said diffusion type EL sheet emitting light from at least one selected from the group consisting of (i) the entire area of said EL sheet, (ii) the diaphragm portion only, and (iii) the entire area of said diaphragm portion and an area surrounding said diaphragm portion of said upper surface of said transparent film, said diffusion type EL sheet bowing outwardly in an at-rest state such that said upper surface of said transparent film exhibits a convex shape, said diffusion type EL sheet bowing inwardly when depressed for operation such that said upper surface of said transparent film exhibits a concave shape,

said switch further comprising a membrane switch disposed below said EL sheet diaphragm, said membrane switch being contacted by said EL sheet diaphragm when said EL sheet diaphragm is depressed.

18. A switch according to claim 17, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

19. A switch according to claim 18, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

20. A switch according to claim 17, wherein said transparent electrode layer is formed by printing and drying a paste which is prepared by dispersing conductive powders that have a visible light transmittance in an insulating resin or in a resin solution containing an insulating resin.

21. A switch according to claim 20, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

22. A switch according to claim 21, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

23. A switch according to claim 20, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

24. A switch according to claim 17, wherein a binder resin used for said light emitting layer and said dielectric layer is selected from a vinylidene fluoride rubber, vinylidene fluoride copolymer rubber, a resin prepared by blending cyanated pullulan and cyanated polyvinyl alcohol, or a resin prepared by blending cyanated cellulose and cyanated polyvinyl alcohol.

25. A switch according to claim 24, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

26. A switch according to claim 25, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

27. A switch according to claim 24, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

28. A switch according to claim 17, wherein said transparent electrode layer is formed by printing and drying a paste which is prepared by dispersing conductive powders that have a visible light transmittance in an insulating resin, or in a resin solution containing an insulating resin and wherein a binder resin used for said light emitting layer and said dielectric layer is selected from vinylidene fluoride rubber, vinylidene fluoride copolymer rubber, a resin prepared by blending cyanated pullulan and cyanated polyvinyl alcohol, or a resin prepared by blending cyanated cellulose and cyanated polyvinyl alcohol.

29. A switch according to claim 28, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

30. A switch according to claim 29, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

31. A switch according to claim 28, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

32. A switch according to claim 17, wherein at least one color of light is emitted from said light emitting layer of said EL sheet, and said transparent film is colored, a color paint is applied to said transparent film, or a color film is placed on a convex surface of said EL sheet diaphragm so that said color of light emitted by said EL sheet is at least partly changed.

33. A switch comprising an EL sheet diaphragm including a diffusion type EL sheet having a diaphragm portion exhibiting a dome shape and a flange supporting portion disposed about the outer circumference of said diffusion type EL sheet, said diffusion type EL sheet comprising:

a transparent film having an upper surface and a lower surface,

a transparent electrode layer formed on said lower surface of said transparent film,

a light emitting layer formed on said transparent electrode layer,

a dielectric layer formed on said light emitting layer,

a rear electrode layer formed on said dielectric layer,

an insulating layer formed on said rear electrode layer, and

an upper electrode formed on said insulating layer,

said diffusion type EL sheet emitting light from at least one selected from the group consisting of (i) the entire area of said EL sheet, (ii) the diaphragm portion only, and (iii) the entire area of said diaphragm portion and an area surrounding said diaphragm portion of said upper surface of said transparent film, said diffusion type EL sheet bowing outwardly in an at-rest state such that said upper surface of said transparent film exhibits a convex shape, said diffusion type EL sheet bowing inwardly when depressed for operation such that said upper surface of said transparent film exhibits a concave shape,

said switch further comprising an insulating base film disposed below said EL sheet diaphragm, said insulating base film having a base electrode disposed thereon, said upper electrode and said base electrode contacting one another when said EL sheet diaphragm is depressed.

34. A switch according to claim 33, wherein said transparent electrode layer is formed by printing and drying a paste which is prepared by dispersing conductive powders that have a visible light transmittance in an insulating resin or in a resin solution containing an insulating resin.

35. A switch according to claim 34, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

36. A switch according to claim 33, wherein a binder resin used for said light emitting layer and said dielectric layer is selected from a vinylidene fluoride rubber, vinylidene fluoride copolymer rubber, a resin prepared by blending cyanated pullulan and cyanated polyvinyl alcohol, or a resin prepared by blending cyanated cellulose and cyanated polyvinyl alcohol.

37. A switch according to claim 36, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

38. A switch according to claim 33, wherein said transparent electrode layer is formed by printing and drying a paste which is prepared by dispersing conductive powders that have a visible light transmittance in an insulating resin, or in a resin solution containing an insulating resin and wherein a binder resin used for said light emitting layer and said dielectric layer is selected from vinylidene fluoride rubber, vinylidene fluoride copolymer rubber, a resin prepared by blending cyanated pullulan and cyanated polyvinyl alcohol, or a resin prepared by blending cyanated cellulose and cyanated polyvinyl alcohol.

39. A switch according to claim 38, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.

40. A switch according to claim 33, wherein said transparent film comprises polyethylene terephthalate, and said diaphragm portion is molded by heating said EL sheet comprising said transparent film to 70°

to 180°

C., or heating a mold for said diaphragm portion to 70°

to 180°

C.