JPH09325702A - El sheet diaphragm and switch using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an EL sheet diaphragm which is thin and provides uniform illumination with low power consumption without light loss or luminance unevenness and gives an excellent click feeling at the time of switch depression and a switch which uses the diaphragm as to an illumination type switch used for input operation parts of various electronic equipment. SOLUTION: This EL sheet diaphragm is formed by molding a dispersion type EL sheet, which has an insulating layer containing a light emission body layer 3 sandwiched between a back electrode layer 1 made of a metal plate with spring elasticity and a transparent electrode layer 4a formed on a transparent film 5a so that its light emission surface becomes convex, and counter electrode contacts 9a and 9b are arranged below it to constitute the switch, thereby obtaining the long-life switch which is thin and provides uniform illumination and gives an excellent operation feeling.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an illuminated switch used in an input operation section of various electronic devices, and particularly to an EL sheet diaphragm suitable for a device such as a portable device which is required to be small, thin and lightweight. It relates to a switch using.

[0002]

2. Description of the Related Art In recent years, various electronic devices such as communication devices, video devices, and audio devices have been increasingly used as mobile devices.

Conventionally, illuminated switches of various portable devices have a cannonball type LED mounted in the vicinity of a switch contact portion, or a chip LED mounted in the vicinity of the switch when it is desired to directly illuminate the switch, such as a transparent acrylic plate. The light guide plate was installed to guide the light to the switch and illuminate it.

Dispersion type EL sheets have been conventionally used as backlights for liquid crystal display panels and the like, and a switch in which a pair of transparent electrodes are opposed to each other between a transparent film or glass is placed on the EL sheet. Illuminated switches arranged at are also known.

[0005]

However, in the method of mounting the above-mentioned chip LED in the vicinity of the switch and guiding the light with the light guide plate, the loss of light and the uneven brightness are large, and if the uneven brightness is reduced, the shape becomes large. And then LE
Since the power consumption of D is large, the battery of the portable device consumes quickly and cannot be used for a long time.

A switch having a transparent counter electrode on an EL sheet has an advantage that illumination is extremely uniform, light loss can be reduced, and power consumption can be reduced. There was a problem that the surface design was uniform.

[0007] At present, there is no known EL sheet itself formed by a diaphragm.

In the current EL sheet, a material having no spring property such as aluminum foil or carbon resin paste is used as the back electrode layer, so that a good click operation feeling can be obtained even when the diaphragm is formed. Because it was difficult.

Further, since the current EL sheet uses a hard sputtered film of indium tin oxide (hereinafter referred to as ITO) as a transparent electrode layer, the curvature R = 10.
It can only be used for large curvatures of -50 mm or more, and when an EL sheet is diaphragm-formed, it is extremely stretched and bent, so the ITO film is easily broken during diaphragm forming or diaphragm operation, and the diaphragm forming part There was a possibility that it would stop emitting light.

The present invention solves the above-mentioned problems of the related art. It is thin, consumes less power, provides uniform illumination, has a good operational feeling as a switch, and has a long life. An object is to provide an EL sheet diaphragm having a high degree of freedom and a switch using the same.

[0011]

In order to solve the above-mentioned problems, the present invention uses a metal plate having spring elasticity as the back electrode layer,
An EL sheet diaphragm in which a dispersion type EL sheet in which an insulating layer containing a light emitting body is sandwiched between the back electrode layer and a transparent electrode layer formed on a transparent film is diaphragm-formed so that the light emitting surface is on the convex side. Then, a switch is constructed by arranging a counter electrode contact under the EL sheet diaphragm.

As a result, it is possible to obtain an EL sheet diaphragm and a switch using the same that solve the above problems.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is
A dispersion type EL sheet in which an insulating layer containing at least a light emitting body is sandwiched between a back electrode layer made of a metal plate having spring elasticity and a transparent electrode layer formed on a transparent film layer, and a light emitting surface is on a convex side and This is an EL sheet diaphragm that is formed by a diaphragm so that it has a click feeling against pressing force. When applied as a surface-illuminated switch or its backlight, etc., a switch with a uniform surface emission and a good operation feeling can be obtained. Has the effect of being

According to a second aspect of the present invention, in the EL sheet diaphragm according to the first aspect, the conductive powder having visible light transparency is dissolved in the flexible insulating resin or the flexible insulating resin is dissolved. The paste dispersed in the resin solution is printed and dried to form a transparent electrode layer.When applied as a switch for surface illumination or its backlight, etc., uniform surface emission and good operation feeling can be obtained. In addition, the transparent electrode layer does not break and no longer emits light during molding of the diaphragm or during operation of the diaphragm, which has the effect of dramatically increasing the life of repeated pressing of the diaphragm.

According to a third aspect of the present invention, in the EL sheet diaphragm according to the second aspect, an insulating layer containing a luminous body, a transparent electrode layer, and a transparent film layer made of a transparent insulating resin are sequentially printed on the back electrode layer. The EL diaphragm sheet is formed by stacking, and the insulating layer including the luminous body, the transparent electrode layer, and the transparent film layer can all be formed by printing on the metal plate having the spring elasticity as the back electrode layer. It has the effect that it can be manufactured.

According to a fourth aspect of the present invention, in the EL sheet diaphragm according to any one of the first to third aspects, the binder resin forming the insulating layer including the light emitting body is a vinylidene fluoride rubber or a vinylidene fluoride system. A copolymer rubber or a blended resin of cyanoethyl pullulan and cyanoethyl polyvinyl alcohol or a blended resin of cyanoethyl cellulose and cyanoethyl polyvinyl alcohol, which uses a high dielectric constant and flexible resin,
When applied as a surface-illumination switch or its backlight, etc., it provides uniform surface emission and a good operation feeling, and the insulating layer including the light-emitting body is ruptured during light emission when molding the diaphragm or during operation of the diaphragm. This has the effect of dramatically increasing the life of the repeated pressing operation of the diaphragm.

The invention according to claim 5 is the EL sheet diaphragm according to any one of claims 1 to 4, wherein E
An L sheet or a diaphragm molding die is heated to a temperature not lower than a glass transition temperature of a binder resin and a transparent film forming an insulating layer including at least a light-emitting body to form a diaphragm. When the diaphragm is formed, a transparent film or an EL is formed. Since each layer that constitutes can be molded along the back electrode layer made of metal having spring elasticity without causing internal strain, during diaphragm molding and repeated pressing operation,
The pressing force and the click feeling are stably obtained, and in addition, it has an effect that each layer constituting the EL is less likely to be broken during the operation of the diaphragm.

The invention according to claim 6 is a switch in which a membrane switch having counter electrode contacts is arranged on the concave side of the EL sheet diaphragm according to any one of claims 1 to 5, and the EL sheet In addition to having each function of the diaphragm, it has a function of being thin and lightweight, having uniform surface illumination, low power consumption, and a switch circuit having a good operation feeling.

According to a seventh aspect of the present invention, an insulating film and an electrode contact layer are formed on the back electrode layer on the concave surface side of the EL sheet diaphragm according to any one of the first to fifth aspects, and the insulating film faces each other. A switch in which an electrode contact layer facing each other is formed on a base material. The switch has each function of the EL sheet diaphragm, and a switch having uniform surface illumination and a good operation feeling is obtained, and one of the electrode contacts is EL
By forming the sheet diaphragm, it is possible to simplify the configuration and to form a thinner and lighter surface illumination switch circuit.

The invention according to claim 8 is the switch according to claim 7, wherein an insulating rigid base material is used instead of the opposing insulating film base material. By using, it has an effect of having structural strength as a supporting base material of the switch part.

The invention according to claim 9 is the EL sheet diaphragm according to any one of claims 1 to 5 or the switch according to any one of claims 6 to 8, wherein the transparent film layer is a colored transparent film. Or a colored film is applied to the transparent film layer or a colored film is arranged on the convex surface of the EL sheet diaphragm to change the emission color of the EL sheet entirely or partially.
It has an effect that the emission color of the L sheet diaphragm or EL sheet diaphragm switch can be freely changed within the range of the emission spectrum or can be multicolored.

The invention according to a tenth aspect is the first to fifth aspects.
And the EL sheet diaphragm according to any one of 9 above,
Alternatively, in the switch according to any one of claims 6 to 9, the insulating layer including a light-emitting body has two or more emission colors, and the EL sheet diaphragm or the EL sheet diaphragm switch according to the present invention emits light. It has the effect that colors can be freely changed and multiple colors can be obtained.

The invention described in claim 11 is the invention as defined in claims 1-5.
And the EL sheet diaphragm according to any one of claims 9 and 10, or the switch according to any one of claims 6 to 10, wherein at least the light emitting portion is limited to the diaphragm or the diaphragm and the vicinity thereof, and the surface emitting portion is By limiting to the necessary part, there is an effect that the power consumption can be reduced and the battery life of the portable device or the like can be extended.

The invention as defined in claim 12 is defined by claim 1 through claim 5.
And the EL sheet diaphragm according to any one of claims 9, 10 and 11, or the switch according to any one of claims 6 to 11, on the surface of the transparent film layer or at least one layer between the transparent film layer and the back electrode layer. It is a single-color or multi-color character printing. When molding multiple EL sheet diaphragms or switch diaphragms using them, each diaphragm can be marked and characterized. Have.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
7 will be described. (Embodiment 1) FIG. 1 is an external perspective view of an EL sheet diaphragm according to the present invention, and FIG. 2 is a sectional view of an EL diaphragm molding portion taken along the line AB of FIG.

In the figure, the back electrode layer 1 has a material thickness of 50 μm.
m is a stainless steel plate material, and the dielectric layer 2 is screen-printed on the back electrode layer 1 with a paste in which BaTiO ₃ powder is dispersed in a solution of vinylidene fluoride-6-fluorinated propylene copolymerized fluororubber dissolved in isophorone. It is formed by drying, and the phosphor layer 3 is screen-printed on the dielectric layer 2 with a paste prepared by dispersing ZnS phosphor powder in a solution of vinylidene fluoride-6-propylene propylene copolymer fluororubber dissolved in isophorone. Dried and formed.

A stainless plate material on which the above layers are formed,
A 50 μm thick polyethylene terephthalate transparent film 5 with a transparent electrode layer 4 formed of sputtered ITO is laminated on the light emitting layer 3 and the transparent electrode layer 4 by pressurizing and heating, and then light is emitted by a diaphragm molding die. An EL sheet diaphragm was produced by molding so that the surface was convex.

In FIG. 1, the inside of the dotted line 7 is the light emitting portion,
Reference numeral 6 denotes a diaphragm molded portion formed by diaphragm molding, and 8 denotes external connection electrodes of the back electrode layer 1 and the transparent electrode layer 4, respectively.

When AC 100 V 400 Hz was applied to the external connection electrode 8 of the EL sheet diaphragm in the present embodiment, the light emitting section 7 including the diaphragm molding section 6 was turned on uniformly.

The total thickness including the diaphragm molding portion 6 is 0.
It was 32 mm. Also, the operation feeling curve when the diaphragm was inverted by pressing the diaphragm molding portion 6 from above was measured. As a result, as shown in FIG. 3, the click feeling was good with respect to the pressing force.

Next, the diaphragm molding portion 6 was repeatedly tapped. After repeated keystrokes for 5,000 times, the click feeling was almost unchanged from the initial state, but the diaphragm molding portion 6 did not emit light.

Although a stainless steel plate is used as the back electrode layer 1 in the present embodiment, various metal plates having spring elasticity such as nickel silver, phosphor bronze, beryllium copper, nickel and nickel alloy can be applied.

The EL sheet diaphragm according to the present embodiment is generally composed of the light emitting layer 3 and the dielectric layer 2 as the insulating layer containing the light emitting body.
Between the transparent film 5 and the transparent film 5, an insulating layer made of a light-transmissive insulating resin may be added, or the dielectric layer 2 may be removed by adding an insulating layer. Even in terms of structure, the EL sheet diaphragm of the present invention may have any operational effect.

Although vinylidene fluoride-6-fluorinated propylene copolymer fluororubber was used as the binder resin for the dielectric layer 2 and the light-emitting layer 3, vinylidene fluoride-4 fluoroethylene was used as the same high dielectric resin. -6 Fluorinated propylene copolymer Fluoro rubber, cyanoethyl resins such as cyanoethyl pullulan, cyanoethyl cellulose, cyanoethyl poval, cyanoethyl sucrose, and polysaccharides may be applied alone or in combination. The solvent that dissolves the various binder resins may be appropriately selected depending on the solubility of the resin and the drying conditions.

(Second Embodiment) In the first embodiment,
When forming the diaphragm, the molding die was heated to 150 ° C. to form the diaphragm, thereby forming an EL sheet diaphragm.

When AC 100 V 400 Hz was applied to the external connection electrode 8 of the EL sheet diaphragm in the present embodiment, the light emitting section 7 including the diaphragm molding section 6 was turned on uniformly.

Further, the operation feeling curve when the diaphragm was inverted by pressing the diaphragm molding portion 6 from above was measured. As a result, as in the case of the first embodiment, a good click feeling with respect to the pressing force was obtained.

Next, the diaphragm molding portion 6 was repeatedly tapped. Even after repeatedly hitting the keys 20,000 times, the light emitting state and the click feeling were almost unchanged from the initial values. The emission state became unstable after 20,000 times.

(Third Embodiment) In the second embodiment,
Replacing with a 50 μm polyethylene terephthalate transparent film 5 with a transparent electrode layer 4 by sputtered ITO,
Light-transmitting conductive material in which 70 parts by weight of a phenoxy resin, 30 parts by weight of an epoxy resin and 5 parts by weight of an imidazole blocked isocyanate as a curing agent are mixed and a needle-shaped transparent conductive indium tin oxide powder is dispersed in a resin solution dissolved in isophorone. An EL sheet diaphragm was similarly prepared using the 25 μm polyethylene terephthalate transparent film 5a on which the paste was screen-printed and dried to form the transparent electrode layer 4a.

When AC 100 V 400 Hz was applied to the external connection electrode 8a of the EL sheet diaphragm in the present embodiment, the light emitting section 7a including the diaphragm molding section 6a was illuminated uniformly. Also, the diaphragm molding portion 6a
The operation feeling curve when the diaphragm was inverted by pressing from above was measured. The results are shown in the first and second embodiments.
Similarly to the above, it had a good click feeling with respect to the pressing force.

Next, the diaphragm molding portion 6a was repeatedly tapped. After repeatedly hitting the keys for 500,000 times, the light emission state and the click feeling were almost unchanged from the initial values.

In this embodiment, a blend resin of a phenoxy resin and an epoxy resin is used as the binder resin of the transparent electrode layer 4a, but a urethane resin, a polyester resin, an acrylic resin, various organic materials having flexibility and rubber elasticity are used. A rubber-based resin that is soluble in a solvent can be applied.

The transparent film 5a is the transparent electrode layer 4a.
Since a polyethylene terephthalate film was used in the present embodiment to form a simple method of printing,
Polyacrylic film, polycarbonate film,
Various films such as polysulfone film, polyethersulfone film, polyetheretherketone film, polyetherimide film, polyvinylidene chloride film, polyvinylidene fluoride film and various olefin films can be freely applied.

(Embodiment 4) A paste in which BaTiO ₃ powder is dispersed in a solution of vinylidene fluoride-6-propylene propylene fluoride copolymerized fluororubber dissolved in isophorone on the back electrode layer 1 made of a stainless steel plate material having a thickness of 50 μm. The dielectric layer 2 is formed by screen-printing and drying with, and a paste in which ZnS phosphor powder is dispersed in a solution in which vinylidene fluoride-6-propylene propylene copolymer fluororubber is laminated on the dielectric layer 2 and dissolved in isophorone. Then, the phosphor layer 3 is formed by screen printing and drying, and is laminated on the phosphor layer 3 and mixed with 70 parts by weight of a phenoxy resin, 30 parts by weight of an epoxy resin and 5 parts by weight of an imidazole blocked isocyanate as a curing agent to form isophorone. A transparent electrode layer 4b made of a light-transmitting conductive paste in which needle-shaped transparent conductive indium tin oxide powder is dispersed in a dissolved resin solution. E formed by screen-printing and drying the transparent electrode layer 4 and screen-printing and drying the transparent film layer 5b with a transparent acrylic resin solution.
The L sheet was molded with a diaphragm molding die so that the light emitting surface was convex, to prepare an EL sheet.

When AC 100 V 400 Hz was applied to the external connection electrode 8b of the EL sheet diaphragm in the present embodiment, the light emitting section 7b including the diaphragm molding section 6b was illuminated uniformly. Also, the diaphragm molding portion 6b
The operation feeling curve when the diaphragm was inverted by pressing from above was measured. The result was that it had a good click feel to the pressing force.

Next, the diaphragm molding portion 6b was repeatedly tapped. After repeatedly hitting the keys for 500,000 times, the light emission state and the click feeling were almost unchanged from the initial values.

(Embodiment 5) A cross-sectional view of a switch in which a membrane switch 10 is arranged so that opposed contacts 9a and 9b are located below a diaphragm molding portion 6a of an EL sheet diaphragm manufactured in Embodiment 3 is shown in FIG. Shown in.

Pushing the diaphragm molding portion 6a from above
When pressed with 3, a good click feeling is obtained when the diaphragm is inverted, and at the same time, the opposing contact 9 of the membrane switch 10 is
It was confirmed that a and 9b contacted each other and turned on. FIG. 5 shows a state in which the opposing contacts 9a and 9b of the membrane switch 10 are in contact with each other when the diaphragm is inverted.

The base material 12a on the EL sheet diaphragm side of the membrane switch 10 needs to be a film, but the base material 12b on the opposite side may be a film or a rigid base material such as a glass epoxy laminate.

The spacers 11a and 11b may be one layer as long as a predetermined space can be obtained.

(Sixth Embodiment) In the third embodiment,
An insulating layer 14 is formed on the surface of the back electrode 1 opposite to the dielectric layer 2 and the light emitting layer 3 of the stainless steel plate, a counter contact 9c is formed on the insulating layer 14, and after diaphragm formation, below the diaphragm formation portion 6c. FIG. 6 shows a cross-sectional view of the switch in which the wiring board 15 is arranged so that the counter contact 9d is located at the position.

Pushing the diaphragm forming portion 6c from above from the push rod 1
It was confirmed that pressing with 3 gave a good click feeling at the time of diaphragm reversal, and at the same time, the opposing contact 9c on the insulating layer 14 and the opposing contact 9d of the wiring board 15 were brought into contact with each other to be turned on.

As the base material 16 of the wiring board 15, a film base material such as a polyethylene terephthalate film or a rigid base material such as a glass epoxy laminated plate or a paper phenol laminated plate can be selected. In particular, when a rigid base material is used, it also has a function as a support base material for the EL sheet diaphragm switch.

(Embodiment 7) In Embodiment 1,
As shown in the external perspective view of FIG.
A multicolored EL sheet diaphragm in which the part indicated by is white and the part indicated by Y is blue-green is manufactured, and a desired image character, characters, and numbers are printed on the EL sheet diaphragm, and the display sheet 17 and the transparency are formed. The liquid crystal display element 18 was installed. Display sheet 1
No. 7 is a light-shielding black background, and the image characters, letters, and numbers are light-transparently colored. As for coloring, the portion corresponding to the emission color of blue green was white, and the portions corresponding to the emission color of white were red, white and yellow green.

When the EL sheet diaphragm is turned on in the dark, the color seen through the display sheet 17 is blue green in the part corresponding to the emission color of blue green, and the part corresponding to the emission color of white is displayed. The image characters, letters, and numbers on the sheet were colored.

For comparison, when replaced with an EL sheet diaphragm that emits a single blue-green color and turned on,
No light was transmitted through the red-colored area, and numbers could not be seen in the dark.

It is to be noted that the luminescent color can be made multicolored by changing the luminescent color of the luminescent layer as in the present embodiment, arranging a colored display sheet on the EL sheet diaphragm, or the EL sheet diaphragm itself. The method of making the transparent film layer of the above into a colored transparent film or the method of applying a colored coating material to the transparent film layer can be freely selected.

[0058]

As described above, according to the present invention, uniform light emission, which is a feature of a general EL lamp, is thin, has low power consumption, and is free from light loss and uneven brightness. It can be used for a long period of time, and in addition, a good click feeling against the pressing force can be obtained when the switch is operated, and it is possible to obtain an unprecedented EL sheet diaphragm or a switch using an EL sheet diaphragm that has an excellent operation feeling. Have an effect.

Further, the emission color and display of the surface can be freely selected, and there is an effect that the degree of freedom in designing the operation surface is high.

[Brief description of drawings]

FIG. 1 is an external perspective view of an EL sheet diaphragm according to a first embodiment of the present invention.

FIG. 2 is a sectional view of an EL diaphragm molding portion taken along the line AB of FIG.

FIG. 3 is a characteristic diagram showing an operation feeling of the EL diaphragm molding portion.

FIG. 4 is a sectional view of a switch using an EL sheet diaphragm according to a fifth embodiment of the present invention.

FIG. 5 is a cross-sectional view when a switch using the EL sheet diaphragm is pushed with a push rod.

FIG. 6 is a sectional view of a switch using an EL sheet diaphragm according to a sixth embodiment of the present invention.

FIG. 7 is a perspective view showing a combination of an EL sheet diaphragm, a liquid crystal display element, and a display sheet according to a seventh embodiment of the present invention.

[Explanation of symbols]

 1 Back Electrode Layer 2 Dielectric Layer 3 Light-Emitting Layer 4, 4a, 4b Transparent Electrode Layer 5, 5a, 5b Transparent Film 6, 6a, 6b Diaphragm Molding Section 7, 7a, 7b Light-Emitting Section 8, 8a, 8b External Connection Electrode 9a, 9b, 9c, 9d Counter contact 10 Membrane switch 11, 11a, 11b Spacer 12a, 12b Base material 13 Push rod 14 Insulating layer 15 Wiring board 16 Base material 17 Display sheet 18 Transparent liquid crystal display element

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Heiji Ikoma, 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (12)

[Claims] 1. A dispersion-type EL device in which an insulating layer containing at least a light-emitting body is sandwiched between a back electrode layer made of a metal plate having spring elasticity and a transparent electrode layer formed on a transparent film layer.
An EL sheet diaphragm in which a sheet is formed by a diaphragm so that the light emitting surface has a convex side and has a click feeling against a pressing force. 2. A transparent electrode obtained by printing and drying a paste in which a conductive powder having visible light transparency is dispersed in a flexible insulating resin or a resin solution in which the flexible insulating resin is dissolved. The EL sheet diaphragm according to claim 1, wherein a layer is formed. 3. The EL sheet diaphragm according to claim 2, wherein an insulating layer containing a light emitting body, a transparent electrode layer, and a transparent film layer made of a transparent insulating resin are sequentially printed and laminated on the back electrode layer. 4. The binder resin constituting the insulating layer containing a light emitting body is vinylidene fluoride rubber, vinylidene fluoride copolymer rubber or a blend resin of cyanoethyl pullulan and cyanoethyl polyvinyl alcohol or a blend of cyanoethyl cellulose and cyanoethyl polyvinyl alcohol. The EL sheet diaphragm according to claim 1, wherein a flexible resin having a high dielectric constant selected from resins is used. 5. An EL sheet or a diaphragm molding die is diaphragm-molded by heating at least the glass transition temperature of a binder resin and a transparent film forming an insulating layer containing at least a light-emitting body. EL sheet diaphragm described. 6. A switch in which a membrane switch having counter electrode contacts is arranged on the concave side of the EL sheet diaphragm according to any one of claims 1 to 5. 7. An electrode formed by forming an insulating layer and an electrode contact layer on the back electrode layer on the concave surface side of the EL sheet diaphragm according to claim 1, and facing the insulating film base material. A switch with a contact layer. 8. The switch according to claim 7, wherein an insulating rigid base material is used instead of the facing insulating film base material. 9. The light emission of an EL sheet is made entirely or partially by using a transparent film layer as a colored transparent film, coating a transparent film layer with a colored paint, or disposing a colored film on a convex surface of an EL sheet diaphragm. The EL sheet diaphragm according to any one of claims 1 to 5 in which the color is changed, or the switch according to any one of claims 6 to 8. 10. The EL sheet diaphragm according to any one of claims 1 to 5 and 9, or any one of claims 6 to 9 in which the luminescent color of the insulating layer including a luminescent material is multicolored into two or more types. The switch described. 11. The EL sheet diaphragm according to any one of claims 1 to 5, 9 and 10, or the switch according to any one of claims 6 to 10, wherein at least the light emitting portion is limited to the diaphragm or the diaphragm and its vicinity. . 12. A single-color or multi-color character printing is performed on the surface of the transparent film layer or at least one layer between the transparent film layer and the back electrode layer.
The EL sheet diaphragm according to any one of claims 10 and 11, or the switch according to any one of claims 6 to 11.