JP2857859B2 - EL element fixing device and luminescent clock using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an EL device fixing device and a luminescent timepiece using the same.

[0002]

2. Description of the Related Art The back surface of a normal EL element is coated with a protective film made of a silicon-based resin. However, this protective film has poor adhesiveness, and it is difficult to reliably adhere it with a general adhesive tape. However, when the protective film is changed to another material, E
The properties of the light emitting element of the L element are deteriorated. This is due to the fact that the organic solvent contained in the adhesive of the double-sided adhesive tape enters the EL element inner layer and deteriorates.
The brightness at the position where the double-sided adhesive tape is stuck tends to decrease. In order to suppress the luminance degradation of the EL element as much as possible and extend the light emission life, it is necessary to provide a silicon-based or fluorine-based resin protective film having excellent moisture resistance at a position corresponding to the outside of the back electrode on the back side.

[0003] Therefore, when attaching the EL element to a base material such as a watch exterior frame in a timepiece that emits a dial using the EL element, a special double-sided adhesive tape having high adhesiveness may be used, or As shown in FIG. 2, an adhesive tape 22 is provided so as to straddle the light emitting surface of the EL element 20 and the outer frame 21 and is bonded. On the other hand, although not shown, a dial (front plate) provided with a time index is laminated on the EL element 20 and fixed to the outer frame with a normal double-sided adhesive tape 23. The EL element 20 has a general configuration in which a transparent base sheet on which a transparent electrode is formed, a light emitting layer, an insulating layer, a back electrode, and a protective film made of a silicon-based resin are sequentially laminated.

[0004]

In the above-mentioned conventional configuration,
When a special double-sided adhesive tape is used, there is a problem that the cost of the tape increases. In a configuration that does not use a special double-sided adhesive tape, two types of adhesive tapes are used to fix the base material, the EL element, and the front plate, and the amount of use is large. Since the entire EL element emits light, the adhesive tape overlaps a part of the light-emitting portion, and even if a highly transparent adhesive tape is used, the adhesive tape is made inconspicuous in the light-emitting portion. This is a restriction on the design of the dial.

[0005]

In order to solve the above-mentioned problem, in the present invention, a non-light-emitting portion for attaching an adhesive tape is provided inside a ring-shaped light-emitting portion of an EL element. Is used as a so-called glue allowance. That is, one side of a normal double-sided adhesive tape is attached so as to straddle the non-light-emitting portion and the base material, and the front plate located thereon is fixed on the back surface.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION An EL element fixing device according to the present invention comprises an EL element comprising a light emitting portion formed in a ring shape and a non-light emitting portion provided inside the ring light emitting portion;
A base material on which the back side of the L element is mounted, a light-transmitting front plate disposed on the front side of the EL element, and a light-emitting portion of the EL element; It is arranged so as to protrude to the outside, and one side is bonded to the non-light-emitting portion surface and the surface of the base material, and the other surface is bonded to the back surface of the front plate, so that the base material and the EL element are in front of each other. The EL element has a double-sided adhesive tape for fixing the face plate to each other, and the EL element is formed by sequentially laminating a transparent base sheet made of a substance having a good adherence with a transparent electrode formed on one side and a transparent base sheet on which the transparent electrode is formed. A light-emitting layer, an insulating layer, a back electrode, a protective film, a transparent base sheet on the front surface, a protective film on the back surface is respectively located, the light-emitting layer, the back electrode is formed only in the light-emitting portion, The non-light-emitting part is directly or insulated on the transparent base sheet. Protective film through the body is stuck.

Further, it is effective to adopt the above-described structure in a luminous watch in which the base material is a watch exterior frame and the front plate is a dial provided with a time index.

[0008]

FIG. 1 shows an EL element 1 according to the present invention. The EL element 1 has a light emitting portion 1a (shown by hatching) formed in a ring shape and a tape attached inside the light emitting portion 1a. And a non-light emitting portion 1b. Referring to FIG. 3 in detail, a transparent base sheet 3 made of polyethylene terephthalate (PET) or the like having a transparent electrode 2 made of indium tin oxide (ITO) formed on one side is formed on a transparent electrode forming surface. A light emitting layer 4 printed by mixing a luminous body in which zinc sulfide is doped with copper in a fluororesin binder and an insulating layer 5 printed by mixing a ferroelectric barium titanate in a fluororesin binder to form a laminate Have been. Further, a back electrode 6 made of carbon ink and a protective film 7 made of a silicon-based resin are laminated on the insulating layer 5. The non-light emitting portion 1b is,
Transparent base sheet 3 on which transparent electrode 2 is formed and protective film 7
Are attached only via the insulating layer 5, and the light emitting layer 4,
The back electrode 6 is omitted. Note that the silicone resin forming the protective film 7 has poor adhesion to a general adhesive tape, and the PET forming the transparent base sheet 3 has good adhesion.

FIGS. 2 and 3 show a light-emitting timepiece incorporating the EL element 1 described above. FIG. 2 shows a state in which the EL element 1 is placed on a watch exterior frame 8 serving as a base material, and a normal double-sided adhesive tape 9 is stuck so as to straddle the non-light emitting portion 1 b and the watch exterior frame 8. ing. At this time, the double-sided adhesive tape 9 does not cover the light emitting portion 1a.
Further, as shown in FIG. 3, a translucent dial (front plate) 10 provided with a time index (not shown) is laminated. FIG. 3B shows an enlarged view of a portion A in FIG. 3A, and the dial 10 is fixed by a double-sided adhesive tape 9. Therefore, one side (back side) of the double-sided adhesive tape 9
Are adhered to the surface of the non-light-emitting portion 1b of the EL element 1 and the surface of the exterior frame 8, and the other surface (front surface) is adhered to the back surface of the dial 10, so that the exterior frame 8, the EL element 1 and the Are fixed to each other. A watch mechanical body 11 is provided on the watch exterior frame 8, and a pointer 12 is provided on a pointer shaft 11 a penetrating the watch exterior frame 8, the EL element 1, and the dial 10. As a result, the hands 12 rotate in front of the two-layer luminescent dial of the EL element 1 and the translucent dial 10.

FIG. 4 shows another embodiment. As described above, in the non-light-emitting portion 1b of the EL element 1, the transparent base sheet 3 on which the transparent electrode 2 is formed and the protective film 7 are directly adhered, and the light-emitting layer 4 and the back electrode 6 are insulated. A configuration in which the layer 5 is omitted is also possible.

As described above, in the present invention, the double-sided adhesive tape 9 for fixing the EL element 1, the dial 10 and the outer frame 8 to each other is used.
Is disposed in the non-light emitting portion 1b of the EL element 1, so that the organic solvent contained in the adhesive of the double-sided adhesive tape 9 is
Does not occur due to the intrusion into the inner layer. Therefore, the light emitting portion 1a emits light uniformly without a low-luminance portion for a long time. Further, since the inside of the ring-shaped light emitting portion 1a is a portion which is normally cut and discarded at the time of manufacturing, providing the non-light emitting portion 1b here does not increase the cost.

When a light-collecting member is used as the dial 10, light is transmitted to the non-light-emitting portion 1b inside the light-emitting portion 1a even though the light-emitting portion 1a has a ring shape, as if the entire surface of the EL element emits light. Seen as if you were.

The present invention can be widely applied to various display devices in which a transparent or translucent decorative sheet having an appropriate design is arranged in front of the EL element in addition to the timepiece.

[0014]

As described above, according to the present invention, the base material and the EL
The fixing of the element and the fixing of the front plate and the base material can be performed only with a single double-sided adhesive tape, and the adhesive tape is stuck to the non-light-emitting portion inside the ring-shaped light-emitting portion. Therefore, there is no hindrance to miniaturization, and design constraints are small. Further, since the adhesive tape is adhered to the surface of the EL element having a relatively good adherence, instead of the back surface of the EL element having a poor adherence, stable and reliable fixing is possible.

[Brief description of the drawings]

FIG. 1 is a front view of an EL device of the present invention.

FIG. 2 is a front view of a state in which an EL element is attached to a base material of a light-emitting timepiece.

3A is a sectional view of a light-emitting timepiece, and FIG. 3B is an enlarged view of a portion A.

FIG. 4 is an enlarged sectional view of a main part of another embodiment of the luminescent watch.

FIG. 5 is a front view showing a state in which an EL element is attached to a base material of a conventional light-emitting watch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 EL element 1a Light emitting part 1b Non-light emitting part 2 Transparent electrode 3 Transparent base sheet 4 Light emitting layer 5 Insulating layer 6 Back electrode 7 Protective film 8 Base material (timepiece exterior frame) 9 Double-sided adhesive tape 10 Front plate (character plate)

Claims (2)

(57) [Claims] 1. An EL device comprising: a ring-shaped light-emitting portion; a non-light-emitting portion provided inside the ring-shaped light-emitting portion; and a base on which a back surface of the EL device is mounted. A light-transmitting front plate disposed on the surface side of the EL element; and a light-transmitting front plate disposed so as to protrude from the front-side end of the non-light-emitting part to avoid over the light-emitting part of the EL element. One surface is bonded to the non-light emitting portion surface and the surface of the base material, and the other surface is bonded to the back surface of the front plate. The EL element has a transparent base sheet made of a substance having a good adhesive property and a transparent electrode formed on one surface, and a laminated base sheet formed on the transparent electrode forming surface in this order. Light-emitting layer, insulating layer, back electrode, protective film The transparent base sheet on the front surface, the protective film is located on the back surface, respectively, the light emitting layer, the back electrode is formed only on the light emitting portion, the non-light emitting portion, An EL element fixing device, wherein the protective film is adhered directly on a transparent base sheet or via only the insulating layer. 2. The light-emitting timepiece according to claim 1, wherein the base material is a timepiece exterior frame, and the front face plate is a dial provided with a time index.