JP2009252687A - Method for manufacturing of organic electroluminescent device, and the organic electroluminescent device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing of an organic electroluminescent device and an organic electroluminescent device, wherein an adhesive leaking out of a frame-shaped sealing material is prevented, and furthermore, the nonconformity where inconvenience occurs due to the fact that an inorganic sealing layer is damaged by a gap material. <P>SOLUTION: This method for manufacturing of the organic electroluminescent device is equipped with a process of forming a sealing part 35 by forming a sealing layer surrounding a display region 4 or a region corresponding to this by an organic material which does not contain a gap material in one or both of an element substrate 20 and a sealing substrate 30, arranged opposed to the element substrate 20, and by curing the sealing layer; a process of arranging the liquid adhesive at the region surrounded by the sealing part 35 or a site, corresponding to this of the inner face of the element substrate 20 or of the inner face of the sealing substrate 30; an adhering process of making the inner face of the element substrate 20 and the inner face of the sealing substrate 30 face; and of pasting the element substrate 20 and the sealing substrate 30 via the adhesive. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an organic electroluminescent device and an organic electroluminescent device.

2. Description of the Related Art Conventionally, an organic electroluminescence device (hereinafter, referred to as an organic EL device) including a plurality of light emitting elements that sandwich an organic light emitting layer between a pair of electrodes is known. An organic EL device includes an element substrate including a sealing layer that covers a plurality of light emitting elements (organic EL elements), and a sealing substrate that is disposed to face the element substrate and is bonded to the element substrate via an adhesive layer And a frame-like sealing layer that bonds the peripheral portions of the substrates (see, for example, Patent Document 1).
JP 2003-173868 A

In such a conventional organic EL device, as shown in FIG. 9, an uncured sealing material 50 is usually arranged in a frame shape on an element substrate 60, and a liquid adhesive 62 is arranged on the inside thereof. The sealing substrate 64 is disposed opposite to the element substrate 60 on which the material 50 is disposed, and these are bonded and bonded.
However, when the two substrates 60 and 64 are bonded together via the adhesive 62, the adhesive 62 is compressed between the two substrates 60 and 64 and pushed out of the two substrates 60 and 64, and an uncured frame-shaped seal. There is a possibility that the material 50 is excessively pressed and the adhesive 62 breaks through a part of the sealing material 50 and leaks to the outside. If the adhesive 62 leaks to the outside in this way, the resulting organic EL device will be poorly manufactured and productivity will be reduced.

  Further, when the substrates 60 and 64 are bonded together, a gap material (not shown) such as a resin ball is included in the sealing material 50 in advance so that the distance between the substrates 60 and 64 is set to a predetermined interval. ing. Then, by placing the sealing material 50 containing the gap material on the element substrate 60, the two substrates 60 and 64 are held at a predetermined interval via the sealing material 50. Thereafter, the sealing material 50 and the adhesive 62 are cured in this state, whereby the substrates 60 and 64 are bonded (attached) with the sealing material 50 and the adhesive 62 and fixed.

  Incidentally, since an organic EL element (light-emitting element) is generally easily deteriorated by moisture, a sealing layer 66 is formed on the element substrate 60 so as to cover the organic EL element (not shown) in order to prevent the deterioration. . The sealing layer 66 is formed by laminating an organic sealing layer 67 made of an organic material and inorganic sealing layers 68 and 69 made of an inorganic material. However, as described above, when the two substrates are bonded together via the sealing material 50 containing the gap material, the inorganic sealing layers 68 and 69 are pressed against the gap material by the pressure during the bonding, and are damaged and cracked. May occur. Then, the function as the inorganic sealing layers 68 and 69 is impaired, and the organic EL element is easily deteriorated by moisture.

  The present invention has been made in view of the above circumstances, and the object thereof is to prevent the adhesive from leaking out from the frame-shaped sealing material, and further, the gap sealing material damages the inorganic sealing layer. An object of the present invention is to provide a method for manufacturing an organic electroluminescence device and an organic electroluminescence device, which prevent inconvenience caused by receiving the organic electroluminescence device.

  In order to solve the above problems, a method of manufacturing an organic electroluminescence device according to the present invention includes a step of forming a light emitting element in a display region on an element substrate, and the element substrate and a sealing substrate disposed opposite to the element substrate. Forming a seal layer surrounding the display region or a region corresponding to the display region or a region corresponding to the display region in one or both of them, and further forming the seal portion by curing the seal layer; A step of disposing a liquid adhesive in a region surrounded by the seal portion or a part corresponding to the inner surface of the element substrate or the inner surface of the sealing substrate; and the inner surface of the element substrate and the sealing substrate And a bonding step of bonding the element substrate and the sealing substrate through the adhesive.

According to this method of manufacturing an organic electroluminescence device, a seal layer is formed so as to surround the display region or a region corresponding to the display region, and the seal layer is cured to form a seal portion. A liquid adhesive is disposed in a region surrounded by a corresponding part, and the element substrate and the sealing substrate are bonded to each other through the adhesive. Even if it is pushed out, since the seal portion surrounding it is hardened in advance, it is possible to prevent the disadvantage that a part of the seal portion is broken by the adhesive. Therefore, it is possible to prevent manufacturing defects of the obtained organic EL device and improve productivity.
Moreover, since the sealing layer is formed by forming a sealing layer with an organic material not containing a gap material and curing the sealing layer, an inorganic sealing layer, for example, is applied by the bonding pressure when the two substrates are bonded. Can be prevented from being damaged by being pressed by the gap material. In addition, since the seal portion is cured, the height of the seal portion is set to a predetermined height so that when the two substrates are bonded together, the distance between the two substrates is previously set by the seal portion. It can be held and fixed at a set predetermined interval. Therefore, it is possible to prevent the inconvenience due to the inorganic sealing layer being damaged at the same time as fixing the distance between the two substrates to a predetermined distance.

Further, in the method of manufacturing the organic electroluminescence device, the step of forming the seal portion includes forming a first seal layer that surrounds the display region with an organic material that does not contain a gap material on the element substrate. A process of curing the first seal layer to form the first seal portion, and forming a second seal layer surrounding the region corresponding to the display region with an organic material not containing a gap material on the sealing substrate, Curing the second seal layer to form a second seal portion,
The process of forming the first seal portion is performed together with a process of forming an organic sealing layer that covers the plurality of light emitting elements with an organic material that does not contain a gap material,
In the process of forming the second seal portion, in the step of forming an overcoat layer on the sealing substrate, the thickness of the portion surrounding the region corresponding to the display region is increased, and the thick film portion is formed into the second film portion. The sealing layer may be used.
If it does in this way, about the 1st seal | sticker part, it can form by combining also the process in the existing process, without newly increasing a process. Further, the formation of the second seal portion can be easily performed by partially changing the formation process of the overcoat layer.

In this manufacturing method, it is preferable that the process for forming the first seal layer and the process for forming the organic sealing layer are both performed by the same screen printing method.
If it does in this way, the 1st sealing layer can be formed also forming formation of the existing organic sealing layer, and it becomes advantageous in terms of productivity and cost.

Further, in the method for manufacturing the organic electroluminescence device, the process of forming the sealing layer is performed by surrounding the region corresponding to the display region of the sealing substrate and forming the sealing layer with an organic material that does not contain a gap material. It may be done by doing.
If the sealing layer is formed on the sealing substrate in this way, the light emitting element is not formed on the sealing substrate, and therefore the waiting time in the process is longer than that of the element substrate. Therefore, the sealing layer is formed during this waiting time. As a result, the production efficiency of the entire apparatus can be improved.

In this manufacturing method, the sealing layer is preferably formed by a dispensing method.
In this way, the organic material can be selectively disposed at a desired position, so that loss of the material can be eliminated and the seal layer can be formed with a desired width.

The organic electroluminescence device of the present invention includes an element substrate having a light-emitting element and an organic sealing layer that covers the light-emitting element, and is disposed to face the element substrate, and an overcoat layer is formed on a surface facing the element substrate. A sealing substrate, and an adhesive layer that bonds the element substrate and the sealing substrate and bonds the element substrate and the sealing substrate together. The element substrate has the same process as the organic sealing layer. A first seal portion made of an organic material that does not contain a gap material is formed to surround the display region;
The overcoat layer includes a second seal portion that is formed in a portion surrounding the region corresponding to the display region and that forms a seal portion together with the first seal portion in contact with the first seal portion. The coat layer is formed by a thick film part formed by a thick film,
The adhesive layer is characterized in that it is disposed in a region surrounded by a seal portion composed of the first seal portion and the second seal portion.

According to this organic electroluminescence device, since the adhesive layer is disposed in the region surrounded by the seal portion including the first seal portion and the second seal portion, the element substrate and the sealing substrate can be bonded together. By curing the seal portion in advance, even if the adhesive that becomes the adhesive layer is compressed and pushed out of the two substrates when the two substrates are bonded together, a part of the seal portion that surrounds the adhesive portion is surrounded by the adhesive. It is prevented from being pierced.
In addition, since the first seal portion is formed of the organic material not containing the gap material on the element substrate, the inorganic sealing layer is pressed against the gap material, for example, by the bonding pressure when the two substrates are bonded to each other. It is also prevented from receiving.
Further, the first seal portion is formed not only by a new process but also by a process in an existing process. Furthermore, the second seal portion can be easily formed by partially changing the formation process of the overcoat layer.

  Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, the scale is appropriately changed for each layer and each member so that each layer and each member can be recognized on the drawing.

  FIG. 1 is a schematic diagram showing a wiring structure of an organic electroluminescence device (organic EL device) of the present embodiment. The organic EL device 1 is of an active matrix type using thin film transistors (hereinafter referred to as TFTs) as switching elements, and has a plurality of scanning lines 101 and a direction that intersects each scanning line 101 at a right angle. A wiring configuration including a plurality of signal lines 102 extending and a plurality of power supply lines 103 extending in parallel to each signal line 102, and sub-pixels X are formed in the vicinity of each intersection of the scanning line 101 and the signal line 102 It is.

  A data line driving circuit 100 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 102. Further, a scanning line driving circuit 80 including a shift register and a level shifter is connected to the scanning line 101.

  Further, each of the sub-pixels X includes a switching TFT (switching element) 112 to which a scanning signal is supplied to the gate electrode via the scanning line 101, and a pixel shared from the signal line 102 via the switching TFT 112. A holding capacitor 113 for holding a signal, a driving TFT (switching element) 123 to which a pixel signal held by the holding capacitor 113 is supplied to the gate electrode, and the power supply line 103 through the driving TFT 123 are electrically connected. An anode (pixel electrode) 10 into which a driving current flows from the power line 103 when connected, and a light emitting layer (organic light emitting layer) 12 sandwiched between the anode 10 and the cathode (common electrode) 11 are provided. .

  According to the organic EL device 1, when the scanning line 101 is driven and the switching TFT 112 is turned on, the potential of the signal line 102 at that time is held in the holding capacitor 113, and according to the state of the holding capacitor 113. The on / off state of the driving TFT 123 is determined. Then, a current flows from the power supply line 103 to the anode 10 through the channel of the driving TFT 123, and further a current flows to the cathode 11 through the functional layer 12 including the organic light emitting layer. The functional layer 12 emits light according to the amount of current flowing through it.

  Next, specific modes of the organic EL device 1 of the present embodiment will be described with reference to FIGS. Here, FIG. 2 is a plan view schematically showing the configuration of the organic EL device 1, FIG. 3 is a cross-sectional view schematically showing the organic EL device 1, and FIG. 4 is a diagram showing the main part (A portion) of FIG. It is.

As shown in FIG. 2, the organic EL device 1 includes a TFT element substrate (hereinafter, referred to as an element substrate) 20 that emits an organic light emitting layer by the above-described various wirings, TFTs, and various circuits formed on the element substrate body 21. It has. Although not shown in FIG. 2, the sealing substrate 30 is disposed so as to face the element substrate 20.
The element substrate 20 and the sealing substrate 30 include a display area 4 (area in a frame indicated by a two-dot chain line in the center portion) corresponding to an area where a plurality of light emitting elements and a colored layer, which will be described later, are formed. A dummy region 5 (a region between a one-dot chain line and a two-dot chain line) arranged around is provided.

  In the display area 4, a plurality of pixel areas R, G, and B are arranged in a matrix. Each of the pixel regions R, G, and B includes a light emitting element (organic EL element) including an anode 10 included in the subpixel X of FIG. 1, a functional layer 12 including an organic light emitting layer, and a cathode 11. ing. Then, the light emitted from the light emitting element is transmitted through the colored layers of the pixel regions R, G, and B, so that the R (red), G (green), and B ( (Blue) light can be taken out.

  In addition, each of the pixel regions R, G, and B is arranged in the same color in the vertical direction of the paper, and forms a so-called stripe arrangement. The pixel regions R, G, and B are combined into one display unit pixel, and the display unit pixel performs full color display by mixing the light emission of R, G, and B. .

  Scanning line driving circuits 80 are arranged on both sides of the display area 4 on the element substrate 20 in FIG. 2 and on the lower layer side of the dummy area 5. Further, an inspection circuit 90 is arranged on the upper side in FIG. 2 of the display region 4 on the element substrate 20 and on the lower layer side of the dummy region 5. The inspection circuit 90 is a circuit for inspecting the operating state of the organic EL device 1 and includes, for example, inspection information output means (not shown) for outputting inspection results to the outside, The EL device 1 is configured to be able to inspect the quality and defects.

  As shown in FIG. 3, the organic EL device 1 of the present embodiment is a so-called “top emission structure” organic EL device. Since the top emission structure extracts light not from the element substrate 20 side but from the sealing substrate 30 side, there is an effect that a wide light emitting area can be secured without being affected by the size of various circuits arranged on the element substrate 20. Therefore, luminance can be ensured while suppressing voltage and current, and the lifetime of the light emitting element 22 can be maintained long.

The organic EL device 1 includes an element substrate 20 and a sealing substrate 30 that is disposed to face the element substrate 20 and is bonded to the element substrate 20 via an adhesive layer 34 and a seal portion 35.
On the element substrate 20, a plurality of light emitting elements 22 are formed with a functional layer 12 including an organic light emitting layer (not shown) interposed between the anode 10 and the cathode 11. And the sealing layer 23 is formed so that these light emitting elements 22 may be covered.

  The element substrate 20 includes an element substrate main body 21 and an inorganic insulating layer 14 that covers a surface (inner surface) of the element substrate main body 21 on the sealing substrate 30 side. The element substrate main body 21 is formed of, for example, glass or silicon, and the inorganic insulating layer 14 is formed of silicon nitride or the like. On the element substrate main body 21, the driving TFT 123 and other various wirings shown in FIG. 1 (not shown in FIG. 3) are formed, and the inorganic insulating layer 14 is formed so as to cover them.

On the inorganic insulating layer 14, a planarizing layer 16 is formed in which a metal reflector 15 made of an aluminum alloy or the like is housed. The planarizing layer 16 is formed of an insulating resin material, for example, a photosensitive acrylic resin or a cyclic olefin resin.
The anode 10 of the light emitting element 22 is formed in a region overlapping the metal reflector 15 on the planarizing layer 16 in a plane. The anode 10 is made of, for example, a metal oxide such as ITO (Indium Thin Oxide) having a high hole injection layer having a work function of 5 eV or more. The anode 10 is connected to the driving TFT 123 on the element substrate body 21 through a contact hole that penetrates the planarization layer 16 and the inorganic insulating layer 14.

An insulating pixel partition wall 13 that partitions the light emitting element 22 is formed on the planarizing layer 16. The pixel partition wall 13 includes a plurality of openings that expose the upper portion of the anode 10.
A functional layer 12 is formed so as to cover the upper surfaces of the pixel partition wall 13 and the anode 10 along the uneven shape formed by the opening and the pixel partition wall 13. The functional layer 12 is configured to include an organic light emitting layer (not shown). Examples of the organic light emitting layer include a layer (blue) doped with an anthracene-based dopant in a stricylamine light emitting layer, and the like. A light-emitting material that realizes white light emission by simultaneously emitting light from a layer (yellow) in which a rubrene-based dopant is doped in a stricylamine-based light-emitting layer can be used.

  In the present embodiment, the functional film constituting the functional layer 12 includes a hole injection layer, a hole transport layer, an electron injection layer, an electron injection buffer layer, and the like. That is, a triarylamine multimer (ATP) layer (hole injection layer) and a triphenyldiamine derivative (TPD) layer (hole transport layer) are formed between the anode 10 and the organic light emitting layer. An aluminum quinolinol (Alq3) layer (electron injection layer) and LiF (electron injection buffer layer) are formed and formed between the organic light emitting layer and the cathode 11, respectively. Based on such a configuration, the functional layer 12 facilitates injection of electrons and holes from each electrode, and recombines these electrons and holes well in the organic light emitting layer. .

  A cathode 11 is formed on the functional layer 12 so as to cover the functional layer 12 along the surface shape of the functional layer 12. In the organic EL device 1 having a top emission structure, the cathode 11 needs to be formed of a light transmissive material. Therefore, as the material of the cathode 11, for example, ITO, an indium oxide / zinc oxide based amorphous conductive film (Indium Zinc Oxide), or the like can be used.

For the cathode 11, a material having a large electron injection effect (a work function of 4 eV or less) is preferably used. For example, calcium, magnesium, sodium, lithium metal, or a metal compound thereof. Examples of the metal compound include metal fluorides such as calcium fluoride, metal oxides such as lithium oxide, and organometallic complexes such as acetylacetonate calcium. In addition, these materials alone have high electrical resistance and low performance as an electrode. Therefore, a metal layer such as aluminum, gold, silver, or copper is patterned so as to avoid a light emitting portion, or a transparent layer such as ITO or tin oxide is used. You may use it in combination with the metal oxide conductive layer which has a light property.
In the present embodiment, a laminate of lithium fluoride, a magnesium-silver alloy, and ITO is used as the material of the cathode 11 so as to have a film thickness that can provide translucency.

In addition, an electrode protective layer 17 is formed on the element substrate 20 so as to cover the inorganic insulating layer 14, the planarization layer 16, and the cathode 11 of the light emitting element 22. The electrode protective layer 17 is formed of a silicon compound such as silicon oxynitride, for example, and functions as an inorganic sealing layer.
An organic buffer layer 18 is formed on the electrode protective layer (inorganic sealing layer) 17 so as to cover it. The organic buffer layer 18 is formed so as to fill the uneven shape formed by the pixel partition wall 13 and the opening thereof, and planarizes the element substrate 20, and functions as an organic sealing layer.

  The organic buffer layer 18 is formed of a light-transmitting material, and the raw material main component is formed by a screen printing method under a reduced pressure atmosphere, so that it has excellent fluidity and is free from solvents and volatile components. There is no need to be an organic compound material that is a raw material for the polymer skeleton. As such a material, an epoxy monomer / oligomer having an epoxy group and a molecular weight of 3000 or less is preferably used (monomer definition: molecular weight 1000 or less, oligomer definition: molecular weight 1000 to 3000). For example, bisphenol A type epoxy oligomer, bisphenol F type epoxy oligomer, phenol novolac type epoxy oligomer, polyethylene glycol diglycidyl ether, alkyl glycidyl ether, 3,4-epoxycyclohexenylmethyl-3 ′, 4′-epoxycyclohexene carboxylate, There are ε-caprolactone-modified 3,4-epoxycyclohexylmethyl 3 ′, 4′-epoxycyclohexanecarbochelate, and these are used alone or in combination.

Further, as the curing agent that reacts with the epoxy monomer / oligomer, one that forms a cured film having excellent electrical insulation and adhesiveness, high hardness, toughness and excellent heat resistance, excellent translucency, and curing. An addition polymerization type with little variation in the size is preferred. For example, 3-methyl-1,2,3,6-tetrahydrophthalic anhydride, methyl-3,6-endomethylene-1,2,3,6-tetrahydrophthalic anhydride, 1,2,4,5-benzene Acid anhydride curing agents such as tetracarboxylic dianhydride and 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride are preferred. Furthermore, as reaction accelerators that promote the reaction (ring opening) of acid anhydrides, by adding trace amounts of alcohols with high molecular weight such as 1,6-hexanediol, which are difficult to volatilize, and amine compounds such as aminophenol, It becomes easy to cure. Such curing is performed by heating in the range of 60 to 100 ° C., and the cured film becomes a polymer having an ester bond.
Further, a cation-releasing type polymerization initiator often used for shortening the curing time may be used, but those having a slow reaction are preferable so that curing shrinkage does not rapidly progress. Moreover, what forms a hardened | cured material finally using thermosetting so that a flattening may be advanced by the viscosity fall by the heating after application | coating is preferable.

A gas barrier layer 19 that covers the organic buffer layer 18 is formed on the organic buffer layer (organic sealing layer) 18. The gas barrier layer 19 is formed of, for example, a silicon compound containing nitrogen, that is, silicon nitride, silicon oxynitride, or the like in consideration of translucency, gas barrier properties, and water resistance, and functions as an inorganic sealing layer. To do. In the present embodiment, the light transmittance in the visible light region is set to, for example, 80% or more by appropriately adjusting the material and film thickness of the gas barrier layer 19.
Under such a configuration, in this embodiment, the gas barrier layer (inorganic sealing layer) 19, the electrode protective layer (inorganic sealing layer) 17, and the organic buffer layer (organic sealing layer) 18 are used. A sealing layer 23 covering the light emitting element 22 is configured.

  On the surface of the element substrate 20 on which the gas barrier layer 19 is formed, the sealing substrate 30 is disposed so as to face the surface. The sealing substrate 30 is bonded to the gas barrier layer 19 on the element substrate 20 via the adhesive layer 34 and the seal portion 35. The sealing substrate 30 includes a sealing substrate body 31 made of a light-transmitting material such as glass or transparent plastic (polyethylene terephthalate, acrylic resin, polycarbonate, polyolefin, etc.).

  A red colored layer 37R, a green colored layer 37G, and a blue colored layer 37B are arranged in a matrix on the surface of the sealing substrate body 31 facing the element substrate 20 as the colored layer 37. Further, a black matrix layer (light-shielding layer) 32 that partitions each colored layer 37 is formed around each colored layer 37. The colored layer 37 and the black matrix layer 32 are arranged in the display region 4 shown in FIG. 2 when the sealing substrate 30 is aligned and bonded to the element substrate 20. Moreover, the film thickness of the colored layer 37 is adjusted to, for example, about 0.1 to 1.5 μm, and the width of the colored layer 37 is formed to about 10 to 15 μm.

  Each of the colored layers 37 is disposed so as to overlap the functional layer 12 that is formed on the anode 10 and emits white light so as to overlap in a plane. As a result, the light emitted from the functional layer (organic light emitting layer) 12 passes through each of the colored layers 37 and is emitted to the observer side as each color light of red light, green light, and blue light. Yes.

  Further, an overcoat layer (covering layer) 33 is formed on the sealing substrate body 31 on the colored layer 37 and the black matrix layer 32 formed in the display region 4 so as to cover them. The overcoat layer 33 is formed from the inside of the display area 4 to the outside of the display area 4. The overcoat layer 33 is formed of a resin material such as an acrylic resin or a polyimide resin, and is formed to a thickness of about 2 to 4 μm.

  In the present embodiment, as shown in FIG. 4, the seal portion 35 includes a first seal portion 35a formed on the element substrate 20 side and a second seal portion 35b formed on the sealing substrate 30 side. ing. As will be described later, the first seal portion 35 a is formed by the same process as the process for forming the organic buffer layer (organic sealing layer) 18, and thus is formed of the same organic material as the organic buffer layer 18. Is. That is, the first seal portion 35a is formed mainly of an epoxy resin (epoxy monomer / oligomer having an epoxy group and having a molecular weight of 3000 or less) as described above, and is made of a material that does not contain a gap material such as a resin ball. It is formed.

The first seal portion 35 a is formed in an annular shape so as to surround the display region 4 formed with the functional layer 12, and is formed on the outer side of the organic buffer layer 18 covering the functional layer 12. is there. In addition, since this 1st seal | sticker part 35a is formed by the same process as the organic buffer layer 18, the gas barrier layer 19 formed on the organic buffer layer 18 does not cover the 1st seal | sticker part 35a in this embodiment. And selectively formed only on the organic buffer layer 18.
Here, since the first seal portion 35 a is formed by the same process as the organic buffer layer 18, the first seal portion 35 a is formed to have the same thickness as the organic buffer layer 18. However, as shown in FIG. 3, the distance between the element substrate 20 and the sealing substrate 30 is equal to the thickness of the organic buffer layer 18 plus the thickness of the pixel partition wall 13 and the thickness of the adhesive layer 34. Therefore, naturally, the function of sealing between the element substrate 20 and the sealing substrate 30 cannot be exhibited only by the height of the first seal portion 35a.

  Therefore, the seal portion 35 has a second seal portion 35b in addition to the first seal portion 35a, and the first seal portion 35a and the second seal portion 35b function as a seal portion. It has become. The second seal portion 35b is an annular shape formed on the overcoat layer 33, that is, on the inner surface (front surface) side thereof, in a portion surrounding the region corresponding to the display region 4, and in this embodiment, the overcoat layer 33 is formed by a thick film part formed by partially forming a thick film. Therefore, like the overcoat layer 33, the second seal portion 35b is formed of an acrylic resin, a polyimide resin, or the like.

  Further, the height of the second seal portion 35 b is formed such that the sum of the height of the first seal portion 35 a substantially coincides with the gap between the element substrate 20 and the sealing substrate 30. More precisely, as shown in FIGS. 3 and 4, the first seal portion 35 a is formed on the electrode protection layer (inorganic sealing layer) 17, and the second seal portion 35 b is on the overcoat layer 33. Therefore, the height of the seal portion 35 composed of the first seal portion 35 a and the second seal portion 35 b exceeds the thickness of the electrode protective layer 17 from the gap between the element substrate 20 and the sealing substrate 30. The height is obtained by subtracting the thickness of the coat layer 33. The height of the second seal portion 35b is determined and formed in advance based on the designed gap dimension between the element substrate 20 and the sealing substrate 30.

  The adhesive layer 34 needs to be an organic compound material that is excellent in fluidity and does not have a volatile component such as a solvent as a raw material main component before curing, and is similar to the organic buffer layer 18 and the first seal portion 35a. These materials are used. The same material as the organic buffer layer 18 is also used for the curing agent that reacts with the epoxy monomer / oligomer of the adhesive layer 34.

  In addition, the formation position of the seal | sticker part 35 is a peripheral part of the organic EL apparatus 1, Comprising: It is in a frame part (non-light-emitting part). The frame portion is a non-light emitting portion of the organic EL device 1, and is, for example, a range from the pixel partition wall 13 provided at the outermost end on the element substrate 20 to the end portion of the element substrate 20. As for the width of the seal portion 35, the width d of the first seal portion 35a is formed to be about 1 mm.

  Next, a method for manufacturing the organic EL device 1 of the present embodiment will be described with reference to FIGS. 5A to 5D are process diagrams showing the manufacturing process on the element substrate 20 side, FIGS. 6A to 6C are process diagrams showing the manufacturing process on the sealing substrate 30 side, and FIG. FIGS. 4A and 4B are process diagrams showing an adhesion process between the element substrate 20 and the sealing substrate 30. FIG.

First, as shown in FIG. 5A, various wirings, TFTs, various circuits, an inorganic insulating layer 14, a planarizing layer 16, a metal reflector 15, and a light emitting element 22 are formed on the element substrate body 21 by a known manufacturing method. Then, the pixel partition wall 13 is formed, and an electrode protective layer (inorganic sealing layer) 17 is formed so as to cover them.
The electrode protective layer 17 is formed by depositing, for example, a silicon compound containing nitrogen, that is, silicon nitride, silicon oxynitride, or the like by a high-density plasma film forming method such as an ECR sputtering method or an ion plating method. .

Next, as shown in FIG. 5B, an organic buffer layer (organic sealing layer) 18 is formed on the electrode protection layer 17 with the organic material not containing the gap material, and at the same time, the first seal portion 35a is formed. Form. That is, the process for forming the first seal portion 35 a is performed together with the process for forming the organic buffer layer 18.
Specifically, screen printing is performed under a reduced pressure atmosphere, and a resin is disposed in the formation region of the organic buffer layer 18, and a resin is disposed in the formation region of the first seal portion 35 a and the first seal layer (not shown). Z). Then, the organic buffer layer 18 and the 1st seal | sticker part 35a are formed simultaneously by heating and hardening these resin in the range of 60-100 degreeC.

  At this time, until the material for forming the organic buffer layer 18 passes through the electrode protective layer 17 and the cathode 11 and penetrates into the functional layer 12 such as Alq3 and the dark spot is generated, until the curing proceeds to some extent. Allow to stand at a low temperature, and then raise the temperature when the viscosity is increased to some extent, and complete curing is performed.

Next, as shown in FIG. 5C, a gas barrier layer 19 is formed on the organic buffer layer 18.
Specifically, it is formed by a high density plasma film forming method such as an ECR sputtering method or an ion plating method. In addition, reliability is improved by improving the adhesion by oxygen plasma treatment before the formation. The gas barrier layer 19 is selectively formed and formed only inside the first seal portion 35a as described above by using, for example, a mask. That is, the film is formed such that the gas barrier layer 19 is not formed on the surface of the first seal portion 35a. However, the material of the gas barrier layer 19 is also formed on the first seal portion 35a, and then removed from the first seal portion 35a, whereby the gas barrier layer 19 is selectively formed inside the first seal portion 35a. May be.

Next, as shown in FIG. 5D, a liquid adhesive 34a is disposed on the gas barrier layer 19, that is, in a region surrounded by the first seal portion 35a. Specifically, the above-described thermosetting resin material is disposed and applied by a dispensing method. The adhesive 34a may be disposed on the sealing substrate 30 side described later.
Through the above steps, a plurality of light emitting elements 22 are provided, which are covered with a sealing layer 23 composed of an electrode protective layer 17, an organic buffer layer 18, and a gas barrier layer 19, and further, outside the organic buffer layer 18. Then, the element substrate 20 formed by forming the annular first seal portion 35a formed by the same process as the organic buffer layer 18 is manufactured.

  On the other hand, as shown in FIG. 6A, a colored layer 37 and a black matrix layer 32 are formed on the sealing substrate body 31. As the colored layer 37, a red colored layer 37R, a green colored layer 37G, and a blue colored layer 37B are formed in a matrix corresponding to the display area 4, and each colored layer 37R, 37G, 37B is provided around each colored layer 37R, 37G, 37B. A black matrix layer 32 that partitions 37R, 37G, and 37B is formed.

Specifically, the colored layers 37 </ b> R, 37 </ b> G, and 37 </ b> B are formed so as to face the white functional layer 12 formed on the anode 10. The thickness of the colored layer 37 is preferably as thin as possible in consideration of the light transmittance, and the red colored layer 37R, the green colored layer 37G, and the blue colored layer 37B are respectively formed with the above-described thickness of about 0.1 to 1.5 μm. .
The black matrix layer 32 is formed with a film thickness similar to or greater than that of the colored layer 37.
Specifically, a pattern is formed by a printing method such as a photolithography method or an ink jet method, and the film thickness is appropriately adjusted while adjusting the coating amount in accordance with the material to be used.

Next, as shown in FIG. 6B, an overcoat layer 33 is formed so as to cover the colored layer 37 and the black matrix layer 32 and extend from the inside to the outside of the display region 4.
Specifically, the resin material described above is diluted with a raw material component or an organic solvent, and is applied with a pattern using a flexographic printing method, a gravure printing method, a slit coating method, a screen printing method, etc. Curing is performed.

  In the present embodiment, in the step of forming the overcoat layer 33, a thick film portion is formed by forming a thick film portion in a portion surrounding the region corresponding to the display region 4, and this thick film portion is 2 seal layers. Specifically, after the overcoat layer 33 is formed as shown in FIG. 6B, the second seal layer surrounding the region corresponding to the display region 4 by, for example, a slit coat method is performed continuously with this process. (Thick film part) is formed. Thereafter, the second seal layer (thick film portion) is heated and cured in a heat oven or the like to form the second seal portion 35b as shown in FIG. 6 (c).

At this time, with respect to the height of the second seal portion 35b to be formed, the sum of the heights of the second seal portion 35b and the first seal portion 35a is a predetermined value between the element substrate 20 and the sealing substrate 30. It is formed so as to substantially match the gap. As for the formation of the second seal portion 35b, for example, the overcoat layer 33 is formed thick, and then a region corresponding to the display region 4 is removed by a predetermined depth to form a recess. It is also possible to increase the thickness of the portion surrounding the area corresponding to the display area 4 and use the thick film portion as the second seal portion 35b.
By forming the second seal portion 35b in this way, the colored layer 37 and the black matrix layer 32 are formed on the sealing substrate body 31, and the overcoat layer 33 and the second seal portion 35b covering these are further formed. The provided sealing substrate 30 is manufactured.

Next, as shown in FIG. 7A, the sealing substrate 30 is opposed to the element substrate 20, and the first seal portion 35a on the element substrate 20 and the second seal portion 35b on the sealing substrate 30 are provided. Facing each other.
Subsequently, the element substrate 20 and the sealing substrate 30 are bonded to each other through the adhesive 34a. At this time, the alignment position of the bonded element substrate 20 and the sealing substrate 30 is finely adjusted so that the first seal portion 35a and the second seal portion 35b are in contact with each other while the element substrate 20 and the sealing substrate 30 are sealed. Both of the substrates 30 are brought closer.

  Specifically, the element substrate 20 and the sealing substrate 30 are relatively moved in the plane direction (parallel direction), and the facing position between the light emitting element 22 and the coloring layer 37 is adjusted. For example, the positional deviation between the light emitting element 22 and the colored layer 37 is adjusted to be 2 μm or less. In this way, final alignment (correction) is performed. Then, the first seal portion 35a and the second seal portion 35b are brought into contact with each other and brought into contact with each other, thereby forming the seal portion 35.

Next, while adjusting the alignment position accuracy, the element substrate 20 and the sealing substrate 30 are pressure-bonded via the adhesive 34a while being held at a pressure of 600 N for 200 seconds in a vacuum atmosphere with a degree of vacuum of 1 Pa, for example.
Then, the adhesive 34a compressed between the sealing substrate 30 and the element substrate 20 and pushed to the outer peripheral side of the sealing substrate 30 is, as shown in FIG. It is dammed by the seal part 35 including the second seal part 35b. That is, since both the first seal portion 35a and the second seal portion 35b are already cured, the first seal portion 35a and the second seal portion 35b are blocked against the flow of the adhesive 34a, and a part of the seal portion 35 is broken through. There is no end.

Next, the element substrate 20 and the sealing substrate 30 bonded by pressure bonding are heated in an air atmosphere. Specifically, the adhesive 34 a is thermally cured by heating at about 60 to 100 ° C. in the atmosphere with the element substrate 20 and the sealing substrate 30 bonded together, and the adhesive layer 34 is formed. This adhesive layer 34 also has a role of protecting the gas barrier layer 19, and when left in a place where the liquid barrier layer 19 is heated to a high temperature, the liquid adhesive layer 34 (adhesive 34 a) convects in the apparatus. Since the gas barrier layer 19 may be damaged, the adhesive layer 34 must be cured.
As described above, the organic EL device 1 of this embodiment shown in FIG. 3 can be manufactured.

According to such a method of manufacturing the organic EL device 1, even when the adhesive 34 a is compressed and pushed outward when the element substrate 20 and the sealing substrate 30 are bonded together, the sealing portion 35 surrounding the adhesive 34 a is cured in advance. Therefore, it is possible to prevent the disadvantage that a part of the adhesive 34a is broken through.
Further, the first seal layer and the second seal layer are formed of an organic material not containing a gap material, and the seal portion 35 including the first seal portion 35a and the second seal portion 35b is formed by curing these seal layers. Therefore, at the time of bonding of both substrates, for example, the electrode protective layer (inorganic sealing layer) 17 is pressed against the gap material by the bonding pressure, and damage can be prevented. Therefore, in this manufacturing method, it is possible to prevent manufacturing defects of the obtained organic EL device 1 and improve productivity.

In addition, by forming the height of the seal portion 35 including the first seal portion 35a and the second seal portion 35b to a predetermined height, when the two substrates are bonded together, the seal portion 35 The distance between the two substrates can be held and fixed at a predetermined distance set in advance. Therefore, it is possible to prevent the inconvenience due to the electrode protective layer (inorganic sealing layer) 17 being damaged as described above, while fixing the distance between the two substrates to a predetermined distance.
Furthermore, since the process for forming the first seal part 35a is performed together with the process for forming the organic buffer layer (organic sealing layer) 17, the existing process is not added to the first seal part 35a without newly adding processes. It can be easily formed by also serving as the process in (1). Further, since the process of forming the second seal portion 35b is performed by increasing the film thickness of the portion surrounding the region corresponding to the display region 4 in the step of forming the overcoat layer 33, the overcoat layer This can be easily performed by partially changing the formation process of 33.

  In particular, since the second seal portion 35b is formed of the same acrylic resin, polyimide resin, or the like as the overcoat layer 33, these resins have higher elasticity than, for example, epoxy resins and are easily elastically deformed. Therefore, when both substrates are bonded together and the first seal portion 35a and the second seal portion 35b are brought into contact with each other, the pressure applied thereto is absorbed by the second seal portion 35b, and the electrode protection layer 17 and the like are damaged. It is prevented.

Further, according to the organic EL device 1 obtained in this way, even when the adhesive 34a that becomes the adhesive layer 34 is compressed and pushed out of both the substrates when the two substrates are bonded together, the adhesive 34a It is prevented that a part of the seal portion 35 surrounding this is broken.
Further, since the first seal portion 35a is formed on the element substrate 20 with an organic material not containing a gap material, the electrode protection layer (inorganic sealing layer) 17 is formed by the bonding pressure when the two substrates are bonded. It is also prevented from being damaged by being pressed by the gap material.
Moreover, the 1st seal | sticker part 35a will be formed by combining the process in the existing process instead of a new process. Further, the second seal portion 35b can be easily formed by partially changing the formation process of the overcoat layer 33.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the embodiment, the first seal portion 35a and the second seal portion 35b are brought into contact with each other to form the seal portion 35. However, the seal portion is not formed on the element substrate 20 side, and the seal substrate 30 side is formed. Only the seal portion may be formed.

  That is, the sealing substrate 30 does not contain a gap material instead of forming the second seal portion 35b as described above after the overcoat layer 33 is formed as shown in FIG. 6B. An organic material, for example, the same acrylic resin, polyimide resin, or epoxy resin as the overcoat layer 33 is used to form the seal layer 38a as shown in FIG. At this time, a dispensing method is preferably used as a method of forming the seal layer 38a. This is because by using the dispensing method, the organic material can be selectively disposed at a desired position, so that loss of the material can be eliminated and the seal layer 38a can be formed with a desired width. Then, after the sealing layer 38a is formed in this way, before the element substrate 20 and the sealing substrate 30 are bonded together, for example, the element substrate 20 and the sealing substrate 30 are cured by heat treatment to form the seal portion 38.

  Here, in the case of forming by the dispensing method, the thickness of the sealing layer 38a to be formed is increased to some extent, and the sealing portion 38 higher than the set gap between the element substrate 20 and the sealing substrate 30 may be formed. . Therefore, according to the height of the seal portion 38 to be formed, for example, as shown in FIG. 8 (b), the overcoat layer 33 is formed one size smaller in advance, and the outer periphery thereof is compared with the state shown in FIG. Alternatively, the sealing portion 38 may be formed directly on the surface (inner surface) of the sealing substrate 30. Furthermore, as shown in FIG. 8C, the formation region of the seal portion 38 in the sealing substrate body 31 is dug in advance by etching or the like to form a concave groove 39, and the seal portion 38 is provided here. You may make it form.

Even if the seal portion 38 is formed in this manner, when the element substrate 20 and the sealing substrate 30 are bonded together, the seal portion 38 is cured in advance, so that part of the seal portion 38 is broken by the adhesive 34a. Such inconveniences can be prevented. Therefore, it is possible to prevent manufacturing defects of the obtained organic EL device and improve productivity.
Further, the seal layer 38a is formed of an organic material that does not contain a gap material, and the seal layer 38 is formed by curing the seal layer 38a. Therefore, when the two substrates are bonded, for example, a gas barrier layer ( It is also possible to prevent the inorganic sealing layer) 19 and the electrode protective layer (inorganic sealing layer) 17 from being pressed and damaged by the gap material. In particular, if the seal portion 38 is formed using an organic material having relatively high elasticity, such as acrylic resin or polyimide resin, which is easily elastically deformed, the gas barrier layer (inorganic sealing layer) 19 is pressed by the seal portion 38. Further, damage to the electrode protective layer (inorganic sealing layer) 17 is also prevented.

  In the above embodiment, the case where the present invention is applied to a top emission type organic EL device has been described. However, the present invention may be applied to a bottom emission type organic EL device.

It is a schematic diagram which shows the wiring structure of the organic electroluminescent apparatus which concerns on this invention. 1 is a plan view schematically showing a schematic configuration of an organic EL device according to the present invention. 1 is a side sectional view schematically showing a schematic configuration of an organic EL device according to the present invention. It is an expanded sectional view of the A section in FIG. (A)-(d) is process drawing which shows the manufacturing process of the organic electroluminescent apparatus based on this invention. (A)-(c) is process drawing which shows the manufacturing process of the organic electroluminescent apparatus based on this invention. (A), (b) It is process drawing which shows the manufacturing process of the organic electroluminescent apparatus concerning this invention. (A)-(c) is principal part sectional drawing which concerns on the manufacturing method of this invention. It is a sectional side view which shows typically schematic structure of the conventional organic EL apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Organic EL device, 4 ... Display area, 10 ... Anode, 11 ... Cathode, 12 ... Functional layer, 17 ... Electrode protective layer (inorganic sealing layer), 18 ... Organic buffer layer (organic sealing layer), 19 ... Gas barrier layer (inorganic sealing layer), 20 ... element substrate, 21 ... element substrate body, 22 ... light emitting element, 23 ... sealing layer, 30 ... sealing substrate, 33 ... overcoat layer, 34 ... adhesive layer, 34a ... Adhesive, 35, 38 ... seal part, 35a ... first seal part, 35b ... second seal part, 38a ... seal layer

Claims (6)

Forming a light emitting element in a display region on the element substrate;
A sealing layer surrounding the display region or a region corresponding to the display region or a region corresponding thereto is formed on one or both of the element substrate and the sealing substrate disposed to face the element substrate with an organic material not containing a gap material, A step of curing the seal layer to form a seal portion;
A step of disposing a liquid adhesive in a region surrounded by the seal portion or a part corresponding to the inner surface of the element substrate or the inner surface of the sealing substrate;
An organic electroluminescence device comprising: an adhesion step in which an inner surface of the element substrate and an inner surface of the sealing substrate are opposed to each other and the element substrate and the sealing substrate are bonded to each other through the adhesive. Device manufacturing method. The step of forming the seal portion includes forming a first seal layer surrounding the display region with an organic material that does not contain a gap material on the element substrate, and then curing the first seal layer to form the first seal portion. Forming a second seal layer surrounding the region corresponding to the display region with an organic material not containing a gap material on the sealing substrate, and then curing the second seal layer to form a second seal portion Forming a process, and
The process of forming the first seal portion is performed together with a process of forming an organic sealing layer that covers the plurality of light emitting elements with an organic material that does not contain a gap material,
In the process of forming the second seal portion, in the step of forming an overcoat layer on the sealing substrate, the thickness of the portion surrounding the region corresponding to the display region is increased, and the thick film portion is formed into the second film portion. The method for producing an organic electroluminescent device according to claim 1, wherein the method is performed by forming a seal layer.   3. The method of manufacturing an organic electroluminescence device according to claim 2, wherein the process of forming the first sealing layer and the process of forming the organic sealing layer are both performed by the same screen printing method.   2. The process for forming the sealing layer is performed by forming a sealing layer with an organic material that does not contain a gap material so as to surround a region corresponding to the display region of the sealing substrate. The manufacturing method of the organic electroluminescent apparatus of description.   The method for manufacturing an organic electroluminescence device according to claim 4, wherein the sealing layer is formed by a dispensing method. An element substrate having a light emitting element and an organic sealing layer covering the light emitting element;
A sealing substrate disposed opposite to the element substrate and having an overcoat layer formed on a surface facing the element substrate;
An adhesive layer that bonds the element substrate and the sealing substrate and bonds the element substrate and the sealing substrate together. The gap formed in the same step as the organic sealing layer is formed on the element substrate. A first seal portion made of an organic material not containing a material is formed surrounding the display region;
The overcoat layer includes a second seal portion that is formed in a portion surrounding the region corresponding to the display region and that forms a seal portion together with the first seal portion in contact with the first seal portion. The coat layer is formed by a thick film part formed by a thick film,
The organic electroluminescence device according to claim 1, wherein the adhesive layer is disposed in a region surrounded by a seal portion including the first seal portion and the second seal portion.

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