JP2019071306A - Light-emitting device - Google Patents

Abstract

To arrange a holding member for holding a substrate of a light-emitting element to have flexibility, thereby lowering a stress to be applied to the light-emitting element when bending them.SOLUTION: A light-emitting device 10 comprises: a first base material 100; a second base material 200; a light-emitting element 300; and a control part 400. The first base material 100 has flexibility and serves to hold the light-emitting element 300. The control part 400 controls the light-emitting element 300. The second base material 200 has flexibility, and it is partially fixed to the first base material 100, thereby forming a space defined between itself and the first base material 100. In the space, the control part 400 is located. A material of the second base material 200 is larger, in flexibility, than a material of the first base material 100.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a light emitting device.

  One of the light sources of the light emitting device is an organic EL element. Since the light emitting layer of the organic EL element is formed of an organic substance, when a flexible substrate is used, the organic EL element can have flexibility. On the other hand, the light emitting device has, in addition to the organic EL element and its substrate, other members such as a holding member for holding them. In order to make the light emitting device itself flexible, these other members also need to be flexible. For example, Patent Document 1 describes that the light guide plate can be bent by providing a thin portion in the light guide plate used for the illumination device.

  Patent Document 2 describes that by attaching a band-like supporter to the back surface of the lighting device, the lighting device can be attached to the back of the hand.

JP 2012-169144 A JP, 2013-145658, A

  As described above, the light emitting device includes the light emitting element such as the organic EL element and the holding member for holding the substrate. In order to make the light emitting device flexible, it is necessary to make the holding member flexible. In order to make the holding member flexible, the holding member may be formed of a flexible material. However, when the light emitting device is bent, a stress is generated at the bonding portion between the substrate of the light emitting element and the holding member, and this stress may be applied to the light emitting element.

  As a problem to be solved by the present invention, one example is to give flexibility to the holding member for holding the substrate of the light emitting element and to lower the stress applied to the light emitting element when these are bent.

The invention according to claim 1 is a first substrate having flexibility,
A light emitting element held by the first base material;
A control unit that controls the light emitting element;
A second base material having flexibility and being partially fixed to the first base material to form a partitioned space between the first base material and the second base material;
Equipped with
The control unit is located in the space;
The material of the second base material is a light emitting device having greater flexibility than the material of the first base material.

  The objects described above, and other objects, features and advantages will become more apparent from the preferred embodiments described below and the following drawings associated therewith.

It is a top view of a light emitting device concerning an embodiment. It is a top view of the 2nd substrate which a light-emitting device has. It is AA sectional drawing of FIG. It is sectional drawing of the light-emitting device made to curve. FIG. 7 is a cross-sectional view showing a configuration of a light emitting device according to a modification 1; It is a top view of the light-emitting device shown in FIG. FIG. 7 is a cross-sectional view showing a configuration of a light emitting device according to a modification 2; FIG. 10 is a cross-sectional view showing a configuration of a light emitting device according to a modification 3; FIG. 13 is a cross-sectional view showing a configuration of a light emitting device according to a modification 4; FIG. 18 is a perspective view showing a configuration of a light emitting device according to a fifth modification. It is BB sectional drawing of FIG. FIG. 21 is a perspective view showing a configuration of a light emitting device according to a modification 6; It is a figure which shows how to use an auxiliary member. FIG. 21 is a perspective view showing a configuration of a light emitting device according to a modified example 7;

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description will not be repeated.

  FIG. 1 is a top view of a light emitting device 10 according to the embodiment. FIG. 2 is a plan view of the second base 200 of the light emitting device 10. FIG. 3 is a cross-sectional view taken along the line AA of FIG. A light emitting device 10 according to the embodiment includes a first base 100, a second base 200, a light emitting element 300, and a control unit 400. The first base material 100 has flexibility, and holds the light emitting element 300. The controller 400 controls the light emitting element 300. The second base material 200 has flexibility, and a part thereof is fixed to the first base material 100 to form a partitioned space with the first base material 100. The control unit 400 and the light emitting element 300 are located in this space. The material of the second base 200 is more flexible than the material of the first base 100. The details will be described below.

The first substrate 100 is used as a substrate of the light emitting device 300. The first base material 100 is formed using, for example, a translucent resin. As this resin, for example, PEN (polyethylene naphthalate), PES (polyether sulfone), PET (polyethylene terephthalate), or polyimide can be used. The thickness of the first base material 100 is, for example, 200 μm or less. In addition, in order to prevent moisture from passing through the first base material 100 and reaching the light emitting element 300, at least the surface on which the light emitting element 300 of the first base material 100 is formed (first surface 110, preferably An inorganic barrier film such as SiN _x or SiON is formed on both the first surface 110 and the second surface 120.

  The light emitting element 300 is, for example, an organic EL element, and includes a first electrode, a second electrode, and an organic layer.

  The first electrode is a light transmitting transparent electrode, and is located on the light emitting surface of the light emitting element 300. The transparent conductive material constituting the transparent electrode is a metal-containing material such as metal oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IWZO (Indium Tungsten Zinc Oxide), ZnO (Zinc Oxide), etc. is there. The thickness of the first electrode is, for example, 10 nm or more and 500 nm or less. The first electrode is formed, for example, using a sputtering method or a vapor deposition method. The first electrode may be a carbon nanotube, or a conductive organic material such as PEDOT / PSS. The first electrode may be provided with an auxiliary electrode. The auxiliary electrode is formed of, for example, a MAM in which a Mo alloy layer, an Al alloy layer, and a Mo alloy layer are laminated in this order.

  The second electrode is made of, for example, a metal selected from the first group consisting of Al, Au, Ag, Pt, Mg, Sn, Zn, and In, or a metal alloy of a metal selected from the first group. Contains layers. In this case, the second electrode has a light shielding property. The thickness of the second electrode is, for example, 10 nm or more and 500 nm or less. However, the second electrode may be formed using the material exemplified as the material of the first electrode. The second electrode is formed by using, for example, a sputtering method or a vapor deposition method.

  The organic layer has, for example, a configuration in which a hole injection layer, a light emitting layer, and an electron injection layer are stacked in this order. A hole transport layer may be formed between the hole injection layer and the light emitting layer. In addition, an electron transport layer may be formed between the light emitting layer and the electron injection layer. Furthermore, it may have a multi-photon structure having a plurality of light emitting layers. In this case, the light emitting layer and the light emitting layer are provided with a charge generating layer or an intermediate electrode formed of a material for forming the first electrode or the second electrode described above. The organic layer may be formed by vapor deposition. In addition, at least one layer of the organic layers, for example, a layer in contact with the first electrode may be formed by an application method such as an inkjet method, a printing method, or a spray method. In this case, the remaining layers of the organic layer are formed by vapor deposition. Also, all layers of the organic layer may be formed using a coating method.

  The light emitting element 300 has a first terminal and a second terminal. The first terminal is electrically connected to the first electrode, and the second terminal is electrically connected to the second electrode. The first terminal and the second terminal are electrically connected to the control unit 400.

  The second base material 200 is, for example, a polygon such as a rectangle, and has a recess 230 in a surface (one surface) opposite to the first base material 100. The recess 230 is provided to arrange the control unit 400. Then, at least a part of a portion of the surface of the second base material 200 in which the recess 230 is not formed is fixed to the first base material 100. In the example shown to this figure, the 2nd base material 200 has the shape which provided the side part 220 protruded toward the 1st surface 110 side in the perimeter of the edge of a plate-shaped base material. In addition, there may be a region where the side portion 220 is not provided at the edge of the second base material 200. The upper surface 222 of the side portion 220 is flat, and is fixed to a portion of the first surface 110 of the first substrate 100 located around the light emitting element 300 using an adhesive or the like. Then, at least a part of the space for accommodating the control unit 400 (the whole of the space in the example shown in the drawing) is formed by the concave portion 230 of the first base 100 and the second base 200. The surface of the first base 100 holding the light emitting element 300 is opposed to the second base 200. For this reason, the light emitting element 300 is located in the above-mentioned space.

  The second base material 200 has flexibility and is formed using a material having higher flexibility than the first base material 100. The material which comprises the 2nd base material 200 is silicone resin and polyurethane, for example.

  The control unit 400 has, for example, a configuration in which a microcomputer and another electric element are attached to a circuit board. Here, the circuit board is preferably flexible. However, in some cases, for example, when the circuit board is small, the circuit board may not have flexibility. The control unit 400 is placed or fixed on, for example, the surface of the second base material 200 facing the first base material 100.

  In the space in which the control unit 400 is accommodated, that is, the space partitioned by the first base 100 and the second base 200, the battery 500 is accommodated. The battery 500 supplies power to the light emitting element 300 through the wiring 520 and the control unit 400. Note that the battery 500 preferably has flexibility. However, in some cases, for example, when the battery 500 is small, the battery 500 may not have flexibility.

  FIG. 4 is a cross-sectional view of the curved light emitting device 10. When the light emitting device 10 is bent, the bonding portion between the first base 100 and the second base 200 (specifically, between the edge of the first base 100 and the upper surface 222 of the side 220 of the second base 200) Stress is generated in the joint). Then, strain is generated in the first base material 100 due to the stress, and as a result, the light emitting element 300 may be stressed. On the other hand, in the present embodiment, the side portion 220 of the second base material 200 is formed using a softer material than the first base material 100. Therefore, the deformation of the side portion 220 reduces the stress applied to the first base 100. As a result, stress applied to the light emitting element 300 can be reduced.

  Here, by adjusting at least one of the thickness of the first base material 100 and the thickness of the second base material 200, it is preferable to prevent the light emitting device 10 from being bent too much. For example, the thickness of the first base material 100 and the second base 100 are set such that the curvature of the light emitting device 10 when the light emitting device 10 applies a force of about 300 N to the light emitting device 10 does not break the light emitting element 300. At least one of the thickness of the material 200 is adjusted.

  In FIG. 4, the light emitting device 10 is curved in the direction in which tensile stress is applied to the first base material 100 (that is, the direction in which the second surface 120 of the first base material 100 is convex). However, the light emitting device 10 may be curved in a direction in which a compressive stress is applied to the first base material 100 (that is, a direction in which the second surface 120 is recessed).

(Modification 1)
FIG. 5 is a cross-sectional view showing the configuration of the light emitting device 10 according to the first modification, and FIG. 6 is a plan view of the light emitting device 10 shown in FIG. 5 corresponds to FIG. 3 of the embodiment, and FIG. 6 corresponds to FIG. 1 of the embodiment. The light emitting device 10 according to this modification has the same configuration as the light emitting device 10 according to the embodiment except for the following points.

  First, the light emitting element 300 is formed not on the first base 100 but on the third base 600. The third substrate 600 is formed using, for example, PEN, PES, PET, or polyimide. The thickness of the third base 600 is, for example, 200 μm or less.

  Then, the first base material 100 has a frame shape and is open except for the edge. In other words, the first substrate 100 has the opening 130. The upper surface 222 of the side portion 220 of the second substrate 200 is fixed to a portion of the first surface 110 of the first substrate 100 located near the outer edge, and the portion located near the inner edge is The edge part of the surface on the opposite side to the light emitting element 300 among the three base materials 600 is fixed. Thereby, at least a part (all in the example of the figure) of the opening 130 is blocked by the third base 600. The light emitting element 300 overlaps with the opening 130.

  When the first base material 100 has a light transmitting property, the first base material 100 may not have the opening 130. In this case, the entire surface of the third base 600 is fixed to the first surface 110 of the first base 100.

  Also in this modification, for the same reason as that of the embodiment, it is possible to reduce the stress applied to the light emitting element 300 when the light emitting device 10 is bent.

  Further, in the embodiment, since the light emitting element 300 is formed on the first base material 100, high flatness, gas barrier property, and the like are required of the first base material 100. For this reason, the manufacturing cost of the 1st base material 100 becomes high. On the other hand, in the present embodiment, since the light emitting element 300 is formed on the third base 600, the third base 600 is required to have high flatness and gas barrier properties. The area of the third base 600 is smaller than the area of the first base 100 in the embodiment. For this reason, the manufacturing cost of the third base 600 is lower than the manufacturing cost of the first base 100 in the embodiment. On the other hand, the first substrate 100 in the present modification is not required to have flatness, gas barrier properties, and the like. Therefore, the manufacturing cost of the first substrate 100 in the present modification is low. As a result, the manufacturing cost of the light emitting device 10 is lower than that of the embodiment.

(Modification 2)
FIG. 7 is a cross-sectional view showing the configuration of the light emitting device 10 according to the second modification, and corresponds to FIG. 3 in the embodiment. In the light emitting device 10 according to this modification, the upper portion of the side portion 220 of the second base material 200 is bent toward the inside of the light emitting device 10, and fixed thereto while covering the edge of the second surface 120 of the first base material 100 The configuration is the same as that of the light emitting device 10 according to the embodiment except for the points described above. In the first modification, the side portion 220 may have the same structure as that of the present modification.

  Also in this modification, for the same reason as that of the embodiment, it is possible to reduce the stress applied to the light emitting element 300 when the light emitting device 10 is bent. In addition, since the second surface 120 of the first base 100 is positioned more inside the light emitting device 10 than the upper portion of the side 220, and the side of the first base 100 is also covered by the side 220, the first base Damage to the light emitting element 300 due to the force applied to 100 can be suppressed.

(Modification 3)
FIG. 8 is a cross-sectional view showing the configuration of the light emitting device 10 according to the third modification, and corresponds to FIG. 3 in the embodiment. A light emitting device 10 according to the present modification is a light emitting device 10 according to the embodiment except that a sheet-like member 700 is provided in a space partitioned by the first base 100 and the second base 200. Is the same as

  The sheet-like member 700 is flexible and flat. The sheet-like member 700 is located between the control unit 400 and the battery 500 and the light emitting element 300. As a result, when the light emitting device 10 is bent, damage to the light emitting element 300 due to the contact of the control unit 400 and the battery 500 with the light emitting element 300 can be suppressed. The material forming the sheet-like member 700 is preferably harder (less stretchable) than the material forming the second base material 200, such as PET.

  In addition, also according to the present modification, it is possible to reduce the stress applied to the light emitting element 300 when the light emitting device 10 is bent, for the same reason as that of the embodiment. Although it is conceivable to fill the space partitioned by the first base material 100 and the second base material 200 with a resin having flexibility, the method shown in this modification is lower in cost and the light emitting device 10 can be reduced in weight.

  In the first and second modifications, the light emitting device 10 may have a sheet-like member 700.

(Modification 4)
FIG. 9 is a cross-sectional view showing the configuration of the light emitting device 10 according to the fourth modification, and corresponds to FIG. 3 in the embodiment. The light emitting device 10 according to this modification has the same configuration as the light emitting device 10 according to the embodiment except for the following points.

  First, the surface of the circuit board of the control unit 400 on which the microcomputer and elements are mounted faces the second base material 200. Therefore, the flat surface of the control unit 400 is opposed to the light emitting element 300. And the recessed part 230 of the 2nd base material 200 is provided corresponding to each of the microcomputer of the battery 500 and the control part 400, and an element. In other words, in the second base material 200, the concave portion 230 for housing the battery 500 and the concave portion 230 for housing the control unit 400 are provided independently of each other.

  Also in this modification, for the same reason as that of the embodiment, it is possible to reduce the stress applied to the light emitting element 300 when the light emitting device 10 is bent. In addition, since the flat surface of the control unit 400 faces the light emitting element 300, the control unit 400 can prevent the light emitting element 300 from being damaged when the light emitting device 10 is bent.

  In the first modification and the second modification, the recess 230 may have the same configuration as that of the present modification.

(Modification 5)
FIG. 10 is a perspective view showing the configuration of the light emitting device 10 according to the fifth modification, and FIG. 11 is a cross-sectional view taken along the line B-B in FIG. The light emitting device 10 according to the present modification has the same configuration as that of the embodiment or any of the first to fourth modifications except that the shape maintaining member 240 is included. In addition, this figure has shown the case similar to embodiment.

  The shape maintenance member 240 is a rod-like member, and is embedded in the lower portion of the side portion 220 of the second base material 200. The shape maintaining member 240 is formed using a material (for example, a metal material such as tin) that can be bent and can maintain the bent shape. In the example shown in this figure, the second base material 200 is a polygon (for example, a rectangle), and the shape maintaining member 240 is provided along each side of the second base material 200. However, at least one side of the second base material 200 may not have the shape maintaining member 240. In addition, the shape maintaining member 240 may have a shape (for example, an L shape) in which the portions embedded in each of the two adjacent sides of the second base material 200 are connected to each other, or the edge of the second base material 200 (For example, a square frame in the case of a rectangle) may be used.

  The shape maintenance member 240 is embedded in the second base material 200, for example, by being inserted into a hole provided in the second base material 200. Under the present circumstances, a part (for example, center part) of shape maintenance member 240 may be fixed (for example, adhesion) to the 2nd substrate 200, and either part of shape maintenance member 240 is fixed to the 2nd substrate 200 It does not have to be done. In this way, compared with the case where the entire shape maintaining member 240 is fixed to the second base material 200, the bending easiness of the second base material 200 can be maintained.

  According to this modification, for the same reason as that of the embodiment, it is possible to reduce the stress applied to the light emitting element 300 when the light emitting device 10 is bent. Further, since the shape maintaining member 240 is also bent when the light emitting device 10 is bent, the light emitting device 10 can maintain the bent state even if the force applied to the light emitting device 10 is zero.

(Modification 6)
FIG. 12 is a perspective view showing the configuration of a light emitting device 10 according to the sixth modification. The light emitting device 10 according to the present modification has the same configuration as that of the embodiment or any of the first to fifth modifications except for the following points.

  First, the second base 200 has two grooves 250 and a slit 260.

  The two grooves 250 are formed on the surface of the second base member 200 opposite to the first base member 100, and are separated from each other. In the example shown to this figure, the 2nd base material 200 is a rectangle, and the groove | channel 250 is formed along 2 sides which mutually oppose among the 2nd base materials 200. As shown in FIG.

  The slit 260 is formed in the side portion 220 of the second base material 200, and can accommodate the auxiliary member 252 (see FIG. 13) therein. The slit 260 may pass through a portion to be a bottom plate of the second base 200, or may be connected to a space divided by the first base 100 and the second base 200.

  FIG. 13 is a view showing how to use the auxiliary member 252. As shown in FIG. The auxiliary member 252 is accommodated in the slit 260 as described above, and taken out of the slit 260 when used. One end of the auxiliary member 252 is fixed to one groove 250, and the other end of the auxiliary member 252 is fixed to the remaining groove 250. The width of the auxiliary member 252 is narrower than the distance between the grooves 250. For this reason, by fixing the auxiliary member 252 to the groove 250, the light emitting device 10 is curved in the direction in which the first base 100 becomes convex. Such usage is employed, for example, when the light emitting device 10 is a desk lamp.

(Modification 7)
FIG. 14 is a perspective view showing the configuration of a light emitting device 10 according to the seventh modification. The light emitting device 10 according to the present modification has the same configuration as that of the sixth modification except for the following points.

  First, the groove 250 is not provided in the second base material 200, and instead, the adhesive layer 254 is provided on the side opposite to 100 of the second base material 200. The adhesive layer 254 is provided to attach the light emitting device 10 to a wall or the like. The adhesive layer 254 is covered by a protective sheet 256. The protective sheet 256 is accommodated in the slit 260 after being peeled off from the adhesive layer 254. Then, after peeling the light emitting device 10 from the wall or the like, the adhesive layer 254 is covered again by the protective sheet 256. Such a method of use is employed, for example, when sticking or peeling the light emitting device 10 on a wall or the like.

  As mentioned above, although an embodiment and an example were described with reference to drawings, these are the illustrations of the present invention and can also adopt various composition except the above.

Claims (1)

A flexible first substrate,
A light emitting element held by the first base material;
A control unit that controls the light emitting element;
A second base material having flexibility and being partially fixed to the first base material to form a partitioned space between the first base material and the second base material;
Equipped with
The control unit is located in the space;
A light emitting device in which the material of the second base material is more flexible than the material of the first base material.

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