JP2017098218A - Display device and organic EL device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device and an organic EL device, in which a substrate is suppressed from being scratched by a spacer.SOLUTION: An organic EL display device includes: an organic EL element displaying an image; an element substrate 30 and a sealing substrate 20 facing to each other with the organic EL element interposed therebetween; a sealing material 43 connecting between the element substrate 30 and the sealing substrate 20; a photo spacer 41 serving as a first spacer, the photo spacer being formed in the sealing member 43 so as to be brought into surface contact with a surface (surface of the element substrate 30) that faces the sealing substrate 20 in the element substrate 30; and a bead spacer 42 serving as a second spacer, the bead spacer being located between the sealing substrate 20 and the photo spacer 41 in the sealing material 43.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a display device and an organic EL (Electro-Luminescence) device.

  Conventionally, for example, an organic EL display device includes an element substrate, a sealing substrate provided facing the element substrate, an organic EL element formed on a surface of the element substrate facing the sealing substrate, and an organic EL And a sealing material for bonding the element substrate and the sealing substrate on the outer periphery of the element. For example, as described in Patent Document 1, spacers made of beads such as glass are mixed in the sealing material.

JP 2009-110785 A

  In the configuration of Patent Document 1, when the element substrate and the sealing substrate are bonded together with the sealing material, the spacer may reach the element substrate through the sealing material and damage the element substrate. The problem that the substrate is damaged by such a spacer is not limited to an organic EL display device, but also in an organic EL device other than a display device such as a display device such as a liquid crystal display device or a lighting device or a printer head light source device. It exists as well.

  The present invention has been made in view of the above-described actual situation, and an object thereof is to provide a display device and an organic EL device in which a substrate is prevented from being damaged by a spacer.

  In order to achieve the above object, a display device of the present invention is provided between a display element for displaying an image, a first and second substrate facing each other through the display element, and the first and second substrates. And a first spacer formed so as to be in surface contact with a surface of the first substrate facing the second substrate in the sealing material, the first spacer being connected to the first substrate and the second substrate; And a second spacer positioned between the second substrate and the first spacer in the sealing material.

  Further, in the display device, the second spacer is a bead spacer formed in a spherical shape or a rod spacer formed in a column shape, and the first spacer is a photo spacer formed in a plate shape, The photo spacer may have an installation surface that faces the second substrate and on which the bead spacer or the rod spacer is installed.

  Further, in the display device, the first substrate includes a plurality of electric lines arranged at different positions in the thickness direction of the first substrate and intersecting when viewed from the thickness direction of the first substrate, The first spacer may be formed at a position different from an intersection where the plurality of electric lines intersect when viewed from the thickness direction of the first substrate.

  In order to achieve the above object, an organic EL device of the present invention is located between an organic EL element, first and second substrates facing each other through the organic EL element, and the first and second substrates. A sealing material for connecting the first and second substrates, a first spacer formed in the sealing material so as to be in surface contact with a surface of the first substrate facing the second substrate, and the seal And a second spacer positioned between the second substrate and the first spacer in the material.

  In the organic EL device, the second spacer is a bead spacer formed in a spherical shape or a rod spacer formed in a column shape, and the first spacer is a photo spacer formed in a plate shape, The photo spacer may have an installation surface that faces the second substrate and on which the bead spacer or the rod spacer is installed.

  Further, in the organic EL device, the first substrate includes a plurality of electric wires arranged at different positions in the thickness direction of the first substrate and intersecting when viewed from the thickness direction of the first substrate, The first spacer may be formed at a position different from an intersection where the plurality of electric lines intersect when viewed from the thickness direction of the first substrate.

  According to the present invention, it is possible to suppress the substrate from being damaged by the spacer.

1 is a schematic cross-sectional view of an organic EL display device according to an embodiment of the present invention. It is the sectional view on the AA line of FIG. 1 is a schematic plan view showing a part of an element substrate according to an embodiment of the present invention.

  An embodiment in which a display device and an organic EL device according to the present invention are embodied in an active matrix organic EL display device will be described with reference to the drawings.

  As schematically shown in FIG. 1, the organic EL display device 1 includes an element substrate 30 that is a first substrate, a sealing substrate 20 that is a second substrate facing the element substrate 30, and sealing in the element substrate 30. The organic EL element 10, which is an example of a display element formed on the surface facing the substrate 20 (the surface of the element substrate 30), and the outer periphery of the organic EL element 10, between the element substrate 30 and the sealing substrate 20. And a seal part 40 positioned.

  The element substrate 30 and the sealing substrate 20 are made of an insulating material such as glass or plastic. On the element substrate 30, TFTs (Thin Film Transistors) (not shown) are arranged in a matrix. In addition, electric lines 31 and 32 including power supply lines and gate lines are wired inside the element substrate 30. The plurality of electric wires 31 extend in the X direction along the surface direction of the element substrate 30, and are arranged along the Y direction substantially along the surface direction of the element substrate 30 and substantially orthogonal to the X direction. The plurality of electric wires 32 each extend in the Y direction and are arranged along the X direction. The plurality of electric wires 31 and the plurality of electric wires 32 are provided at different positions in the thickness direction of the element substrate 30. As shown in FIG. 3, when viewed from the thickness direction of the element substrate 30, a plurality of intersections O of the electric wires 31 and 32 are formed on the element substrate 30.

  As shown in FIG. 1, the organic EL element 10 includes a first electrode 11 (anode) formed on the surface of the element substrate 30, an organic layer 13 formed on the surface of the first electrode 11, and an organic layer. 13 and a second electrode 12 (cathode) formed on the surface.

  The first electrode 11 is formed of ITO (Indium Tin Oxide) or the like, and is formed on the element substrate 30 on the element substrate 30 by means such as vapor deposition or sputtering. The organic layer 13 only needs to have at least a light emitting layer. In this example, the organic layer 13 includes a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer, each of which is a means such as a vapor deposition method or a sputtering method. Are sequentially stacked.

  The second electrode 12 has a function of injecting electrons into the organic layer 13 and is made of a metal such as an aluminum alloy (AlLi, AlCa, AlMg, etc.), a magnesium alloy (MgAg, etc.), for example. The second electrode 12 is formed on the organic layer 13 by means such as vapor deposition or sputtering.

  The seal part 40 is formed in a frame shape surrounding the organic EL element 10 from the outer periphery, and adheres the element substrate 30 and the sealing substrate 20 while maintaining a gap (interval) between the element substrate 30 and the sealing substrate 20. As shown in FIG. 2, the seal portion 40 includes a seal material 43, a plurality of photo spacers 41 corresponding to first spacers, and a plurality of bead spacers 42 corresponding to second spacers.

  The sealing material 43 is made of, for example, a UV (Ultra Violet) curable adhesive, and is positioned between the element substrate 30 and the sealing substrate 20 and connects the element substrate 30 and the sealing substrate 20. Each photo spacer 41 and each bead spacer 42 are located in the sealing material 43. In other words, each photo spacer 41 and each bead spacer 42 are sealed by the seal material 43.

  Each photospacer 41 is formed in a disk shape having a diameter φ of 150 μm and a thickness d of 5 μm, for example. The photo spacers 41 are formed in such a number and size that does not hinder the adhesive force between the element substrate 30 and the sealing substrate 20 by the sealing material 43. Each photospacer 41 is formed on the element substrate 30 by photolithography described later in this example. Each photospacer 41 has an installation surface 41s that faces the sealing substrate 20 and on which the bead spacer 42 can be installed. As shown in FIG. 3, each photo spacer 41 is provided at a position different from the intersection O so as not to overlap the intersection O of the electric wires 31 and 32 when viewed from the thickness direction of the element substrate 30. As the photo spacer 41, for example, Rixon Coat (trademark), which is a photo spacer manufactured by JNC, is employed.

  Each bead spacer 42 is formed in a spherical shape having a diameter φ of 5 μm. The diameter φ of the bead spacer 42 is set to 2/3 or less of the width of the electric wires 31 and 32 (the length in the direction along the surface of the element substrate 30 and perpendicular to the longitudinal direction of the electric wires 31 and 32). Is preferred. As the bead spacer 42, for example, High Presica (registered trademark) which is a silica bead spacer manufactured by Ube Eximo Co., Ltd. is employed.

  The bead spacers 42 a to 42 d are randomly distributed in the seal material 43. The bead spacer 42a is located on the installation surface 41s of the photo spacer 41a, and the bead spacers 42b and 42c are located on the installation surface 41s of the photo spacer 41b. Each of the bead spacers 42 a to 42 c is located between the installation surface 41 s of the photo spacers 41 a and 41 b and the back surface of the sealing substrate 20 (surface facing the element substrate 30), and the installation surface 41 s and the back surface of the sealing substrate 20. Point contact. The bead spacer 42d is located on the first electrode 11 between the two photo spacers 41a and 41b. The distribution mode of the bead spacers 42 shown in FIG. 2 is an example, and the distribution mode of the bead spacers 42 differs depending on the position of the seal portion 40.

(Manufacturing method according to seal 40)
Next, a manufacturing method when the element substrate 30 and the sealing substrate 20 are bonded together by the seal portion 40 will be described.

  Each photo spacer 41 is formed by photolithography. Specifically, each photo spacer 41 is patterned on the element substrate 30 by applying a resist (photosensitive organic substance) on the element substrate 30 and then performing exposure and development through a photomask. Each photospacer 41 is disposed along the outer periphery of the surface of the element substrate 30.

  Then, after mixing a plurality of bead spacers 42 in a liquid UV curable adhesive, the UV curable adhesive is applied along the outer periphery of the back surface of the sealing substrate 20. Next, the sealing substrate 20 is placed on the element substrate so that the UV curable adhesive applied to the sealing substrate 20 abuts on the surface of the element substrate 30 (precisely, the location where each photospacer 41 is formed). Press to 30. Then, the UV curable adhesive is cured by irradiating the UV curable adhesive with UV light, thereby forming the sealing material 43. Thus, the bonding of the element substrate 30 and the sealing substrate 20 is completed.

(Function)
For example, when a compressive force along the thickness direction of the element substrate 30 is applied to the organic EL display device 1, the bead spacer 42 a presses the photo spacer 41 a toward the element substrate 30 as shown in FIG. 2. The photo spacer 41a is deformed so as to be crushed by the force applied from the bead spacer 42a. As described above, the deformation of the photospacer 41a prevents the photospacer 41a from acting as a buffer material, and the bead spacer 42a from damaging the element substrate 30. The photo spacer 41b and the bead spacers 42b and 42c also operate in the same manner as the photo spacer 41a and the bead spacer 42a. Further, since the bead spacer 42d is not positioned on the photo spacer 41, the compressive force is not applied to the bead spacer 42d. Therefore, the bead spacer 42d does not damage the element substrate 30.

(Experimental result)

  The inventor of the present application conducted an experiment to measure the presence / absence of a short circuit of the electric wires 31 and 32 and the peel strength of the seal part in the configuration of the seal part in Comparative Examples 1 and 2 and this embodiment of Table 1 above. In Table 1 above, the gap is the distance between the substrates. The spacer is crushed by being compressed by both substrates. For this reason, a gap becomes small with respect to a spacer.

  In the organic EL display device according to Comparative Example 1, a seal part including only a silica spacer (rod spacer or bead spacer) is employed as a spacer. The rod spacer is formed in a cylindrical shape having a diameter φ of 10 μm. The bead spacer is formed in a spherical shape with a diameter φ of 10 μm.

  In the organic EL display device according to Comparative Example 2, a seal portion including only a photo spacer is employed as the spacer. This photospacer is formed in a disk shape having a diameter φ of 50 μm, 150 μm, or 300 μm and a thickness d of 5 μm.

  In the organic EL display device according to this embodiment, as described above, the seal portion 40 including the photo spacer 41 and the bead spacer 42 is employed. The photo spacer 41 is formed in a disk shape having a diameter φ of 150 μm and a thickness d of 5 μm. The bead spacer 42 is formed in a spherical shape having a diameter φ of 5 μm.

  In the configuration of Comparative Example 1, a short circuit is likely to occur. In particular, in the configuration in which the rod spacer is employed in the comparative example 1, compared to the configuration in which the bead spacer is employed in the comparative example 1, a short circuit is more likely to occur. This is presumably because the rod spacer has a corner portion, and thus it is easy to break through the element substrate through the corner portion to short-circuit the electric wires. In the configuration according to Comparative Example 2 and the present embodiment, no short circuit between the electric wires occurs. In Comparative Example 2, there are no bead spacers or rod spacers that cause a short circuit in the first place, and in the present embodiment, as described above, the photo spacer 41 exists so as to protect the element substrate 30 from the bead spacers 42. Therefore, it is considered that no short circuit occurs.

  In the experiment relating to the peel strength, the element substrate and the sealing substrate are pushed in the direction of separating the element substrate from the sealing substrate in a state where the element substrate and the sealing substrate are sandwiched and fixed by a fixture (not shown) from the thickness direction of the element substrate. When an experiment related to the peel strength was performed, in Comparative Example 1 and the present embodiment, no peeling occurred in the seal portion. In Comparative Example 2, when a photo spacer having a diameter φ of 50 μm and 150 μm was employed, a part of the seal part was peeled off at a high temperature, and when a 300 μm photo spacer was employed, the seal part was peeled off. In Comparative Example 2 in which only the photo spacer is employed, the area where the sealing material adheres the sealing substrate and the element substrate is reduced due to the presence of the photo spacer. For this reason, it is considered that peeling of the seal portion is likely to occur. In particular, in Comparative Example 2, as the diameter φ of the photospacer increases, the adhesion area by the sealing material decreases, and it is considered that peeling is likely to occur. Moreover, in the structure which concerns on the comparative example 2, it is difficult to form with the thickness of about 10 micrometers only with a photo spacer. For this reason, it becomes difficult to ensure a sufficient gap between the substrates.

(effect)
As mentioned above, according to one Embodiment described, there exist the following effects.

  (1) The organic EL display device 1 connects an organic EL element 10 that displays an image, an element substrate 30 and a sealing substrate 20 that face each other via the organic EL element 10, and the element substrate 30 and the sealing substrate 20. A sealing material 43 to be formed, and a photo spacer 41 as a first spacer formed in the sealing material 43 so as to be in surface contact with a surface of the element substrate 30 facing the sealing substrate 20 (a surface of the element substrate 30), In the sealing material 43, a bead spacer 42 is provided as a second spacer that is positioned between the sealing substrate 20 and the photo spacer 41 and makes point contact with the sealing substrate 20 and the photo spacer 41. According to this configuration, since the photospacer 41 is positioned on the surface of the element substrate 30, the bead spacer 42 on the photospacer 41 is suppressed from being damaged.

  (2) The bead spacer 42 is formed in a spherical shape, and the photo spacer 41 is formed in a plate shape. The photo spacer 41 includes an installation surface 41 s that faces the sealing substrate 20 and on which the bead spacer 42 is installed. In a state where the bead spacer 42 is installed on the installation surface 41 s of the photo spacer 41, the distance between the sealing substrate 20 and the element substrate 30 is larger than the diameter φ of the bead spacer 42. For this reason, it is suppressed that the bead spacer 42d which is not located in the installation surface 41s is pushed by the sealing substrate 20 and the element substrate 30, and consequently the element substrate 30 is suppressed from being damaged by the bead spacer 42d.

  (3) The element substrate 30 includes a plurality of electric lines 31 and 32 that are arranged at different positions in the thickness direction of the element substrate 30 and intersect when viewed from the thickness direction of the element substrate 30. The photo spacer 41 is formed at a position different from the intersection O where the plurality of electric lines 31 and 32 intersect as seen from the thickness direction of the element substrate 30. According to this configuration, even if the bead spacer 42 breaks through the photo spacer 41, the bead spacer 42 is located at a position away from the intersection O of the electric wires 31, 32. Is suppressed from short-circuiting.

  Further, the diameter φ of the bead spacer 42 is smaller than the width of the electric wires 31, 32, for example, the diameter φ of the bead spacer 42 is set to 2/3 or less of the width of the electric wires 31, 32. The disconnection of the electric wires 31 and 32 by 42 can be suppressed.

(Modification)
In addition, the said embodiment can be implemented with the following forms which changed this suitably.

  In the above embodiment, the sealing substrate 20 is formed in a flat plate shape, but the shape of the sealing substrate 20 is not limited to this, and may be formed in a U-shaped cross section, for example. In this case, the seal portion 40 is formed between both lower end surfaces of the sealing substrate and the surface of the element substrate 30.

  The diameter φ and the thickness d of the photo spacer 41 in the above embodiment can be changed as appropriate. Moreover, in the said embodiment, although the photo spacer 41 was formed in disk shape, it is not restricted to disk shape, For example, even if it is elliptical plate shape, polygonal plate shape, truncated cone shape, etc. Good.

  In the above embodiment, the photo spacer 41 is employed as the first spacer. However, a solid spacer other than the photo spacer may be employed. For example, the first spacer may be formed on the element substrate 30 by printing.

  In the above embodiment, as shown in FIG. 3, each photo spacer 41 is located at a position different from the intersection point O so as not to overlap with the intersection point O of the electric wires 31 and 32 when viewed from the thickness direction of the element substrate 30. Although formed, each photospacer 41 may overlap with the intersection O of the electric wires 31 and 32.

  The shape of the bead spacer 42 in the above embodiment can be changed as appropriate. For example, instead of the bead spacer 42, a cylindrical rod spacer may be employed. The rod spacer is located between the installation surface 41s of the photo spacers 41a and 41b and the back surface of the sealing substrate 20 (the surface facing the element substrate 30), and is in line contact with the installation surface 41s and the back surface of the sealing substrate 20. May be. As the rod spacer, for example, PF-100 (trade name) which is a glass fiber spacer manufactured by Nippon Electric Glass Co., Ltd. may be employed.

  In the above embodiment, the photo spacer 41 is provided on the element substrate 30 side and the bead spacer 42 is provided on the sealing substrate 20 side. On the contrary, the photo spacer 41 is provided on the sealing substrate 20 side, and the bead spacer 42 is provided. 42 may be provided on the element substrate 30 side.

  In the above embodiment, the organic EL display device 1 is an active matrix system, but may be a passive matrix system.

  In the above embodiment, the organic EL display device 1 includes the seal portion 40. However, a liquid crystal display device including the same seal portion 40 may be used. Further, an organic EL device other than a display device provided with the same seal portion 40 may be used. Specifically, the organic EL device may be an organic EL lighting device, an organic EL printer head light source device, or the like. In the case of such a device, the organic EL element functions as a light emitting element.

DESCRIPTION OF SYMBOLS 1 ... Organic EL display apparatus 10 ... Organic EL element 11 ... 1st electrode 12 ... 2nd electrode 13 ... Organic layer 20 ... Sealing substrate 30 ... Element board | substrate 31, 32 ... Electric wire 40 ... Sealing part 41, 41a, 41b ... Photo spacer 41s ... Installation surface 42, 42a to 42d ... Bead spacer 43 ... Sealing material

Claims (6)

A display element for displaying an image;
First and second substrates facing each other through the display element;
A sealing material located between the first and second substrates and connecting the first and second substrates;
A first spacer formed so as to be in surface contact with a surface of the first substrate facing the second substrate in the sealing material;
A second spacer positioned between the second substrate and the first spacer in the sealing material;
A display device characterized by that. The second spacer is a bead spacer formed in a spherical shape or a rod spacer formed in a columnar shape,
The first spacer is a photo spacer formed in a plate shape,
The photo spacer includes an installation surface that faces the second substrate and on which the bead spacer or the rod spacer is installed.
The display device according to claim 1. The first substrate includes a plurality of electric wires arranged at different positions in the thickness direction of the first substrate and intersecting when viewed from the thickness direction of the first substrate,
The first spacer is formed at a position different from an intersection where the plurality of electric lines intersect when viewed from the thickness direction of the first substrate.
The display device according to claim 1 or 2. An organic EL element;
First and second substrates facing each other through the organic EL element;
A sealing material located between the first and second substrates and connecting the first and second substrates;
A first spacer formed so as to be in surface contact with a surface of the first substrate facing the second substrate in the sealing material;
A second spacer positioned between the second substrate and the first spacer in the sealing material;
An organic EL device characterized by that. The second spacer is a bead spacer formed in a spherical shape or a rod spacer formed in a columnar shape,
The first spacer is a photo spacer formed in a plate shape,
The photo spacer includes an installation surface that faces the second substrate and on which the bead spacer or the rod spacer is installed.
The organic EL device according to claim 4. The first substrate includes a plurality of electric wires arranged at different positions in the thickness direction of the first substrate and intersecting when viewed from the thickness direction of the first substrate,
The first spacer is formed at a position different from an intersection where the plurality of electric lines intersect when viewed from the thickness direction of the first substrate.
The organic EL device according to claim 4, wherein:

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