JP2010198926A - Image display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display apparatus capable of effectively suppressing changes in characteristics of a light-emitting device. <P>SOLUTION: The image display apparatus includes a light-emitting device formed on a device substrate 2, a sealing substrate 8 arranged on the light-emitting device via a sealing member 10 composed of a first polar material to face the device substrate 2, and a polar body that is formed on a region between the device substrate 2 and the sealing substrate 8 that does not overlap the light-emitting device to contact at least part of the sealing member 10 and has a surface composed of a second polar material different from the first polar material. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image display device.

2. Description of the Related Art An image display device in which a current control type light emitting element such as an organic light emitting diode (OLED) is provided between a pair of substrates is widely known. In such an image display device, the light emitting element is sealed by applying an adhesive on the light emitting element formed on the substrate and bonding the pair of substrates through the adhesive.
Here, bubbles are mixed in the adhesive. When the bubbles touch the light emitting element, oxygen contained in the bubbles and an organic material contained in the light emitting element may cause a chemical reaction. And when a light emitting element raise | generates a chemical reaction, the characteristic of a light emitting element changes and the lifetime of a light emitting element may become short. Therefore, techniques for reducing bubbles contained in the adhesive have been proposed (see, for example, Patent Documents 1 and 2). In addition, a technique for reducing bubbles contained in the adhesive has been proposed (see, for example, Patent Document 3).

Japanese Patent Laid-Open No. 2005-5051 JP 2005-32682 A JP 2001-155853 A

  In the technique disclosed in the above-mentioned patent document, when the bubbles contained in the adhesive are reduced, the opportunity for the light emitting element to touch the bubbles is reduced, but the bubbles still easily touch the light emitting elements, and the effect is not sufficient. It was.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an image display device capable of effectively suppressing changes in characteristics of a light emitting element.

  In order to solve the above problems, an image display device according to a first aspect of the present invention includes a light emitting element formed on an element substrate and a sealing material made of a first polar substance on the light emitting element. A sealing substrate disposed opposite to the element substrate; and a surface between the element substrate and the sealing substrate and in contact with at least a part of the sealing material in a region that does not overlap the light emitting element; And a polar body made of a second polar substance different from the first polar substance.

  In the image display device according to the second aspect of the present invention, a plurality of the light emitting elements are provided on the element substrate, and each of the light emitting elements is directed from the element substrate side toward the sealing substrate side. It is characterized by being surrounded by protruding partition walls, and the sealing material is filled in a region surrounded by the partition walls.

  The image display device according to a third aspect of the present invention is characterized in that the polar body is provided in a region surrounded by the partition walls.

  The image display device according to a fourth aspect of the present invention is characterized in that a lower height position of the polar body is located lower than an upper height position of the partition wall.

  In the image display device according to the fifth aspect of the present invention, bubbles are included in the sealing material, and the density per unit volume of the bubbles present above the height position above the partition is determined by the partition. It is characterized by being larger than the density per unit volume of the bubbles existing below the height position of the upper part.

  In the image display device according to the sixth aspect of the present invention, bubbles are contained in the sealing material, and the density per unit volume of the bubbles contained in the sealing material is a region overlapping the light emitting element. Compared to the above, the region which does not overlap with the light emitting element is larger.

  The image display device according to a seventh aspect of the present invention is characterized in that the polar body is provided along an outer periphery of the light emitting element.

The image display device according to an eighth aspect of the present invention is characterized in that a plurality of the polar bodies are provided along the outer periphery of the light emitting element.
The image display device according to a ninth aspect of the present invention is characterized in that the polar body is connected to the sealing substrate.

  In the image display device according to the tenth aspect of the present invention, the polar body is narrower at the lower part than at the upper part, and the tip of the polar body projects from the sealing substrate side toward the element substrate side. Is curved.

  ADVANTAGE OF THE INVENTION According to this invention, the image display apparatus which can suppress effectively that the characteristic of a light emitting element changes can be provided.

1 is a plan view of an image display device according to an embodiment of the present invention. It is the top view to which the pixel which comprises a display part was expanded. FIG. 3 is an enlarged cross-sectional view of one pixel taken along the long dashed line AA in FIG. 2. It is sectional drawing explaining the structural layer of the organic EL element in a pixel. FIG. 5A, FIG. 5B, and FIG. 5C are cross-sectional views of the element substrate showing the manufacturing process of the image display device of this embodiment. 6A and 6B are cross-sectional views of the element substrate showing the manufacturing process of the image display device of this embodiment. 7A and 7B are cross-sectional views of the element substrate showing the manufacturing process of the image display device of the present embodiment. 8A and 8B are cross-sectional views of the sealing substrate showing the manufacturing process of the image display device of the present embodiment. It is sectional drawing of the element substrate and sealing substrate which show the manufacturing process of the image display apparatus of this embodiment. It is sectional drawing of the element substrate and sealing substrate which show the manufacturing process of the image display apparatus of this embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

<1. Schematic configuration of image display device>
FIG. 1 is a diagram showing an image display device 1 according to an embodiment of the present invention. The image display device 1 constitutes a device (organic EL device) using light emission of an organic EL element.

  The image display device 1 is used for home appliances such as a television, electronic equipment such as a mobile phone or a computer device, and includes an element substrate 2 and a mounting circuit 3 mounted on the element substrate 2.

  The element substrate 2 is made of, for example, glass, plastic, metal, or ceramic, and a plurality of pixels 4 are formed in the display unit D1 located in the center of the element substrate 2. A mounting circuit 3 is mounted on the mounting portion D2 located at the end of the element substrate 2.

  The pixel 4 can emit any one of red, green, and blue. This can determine the color to emit light by appropriately selecting the material constituting the organic EL element 5 as the light emitting element as will be described later. In this embodiment, the pixels emit light of red, green, or blue. However, for example, white or orange light may be emitted.

  Here, in the present embodiment, the pixel 4 includes a pixel 4R that emits red light, a pixel 4G that emits green light, and a pixel 4B that emits blue light. A plurality of pixels 4 are provided in a matrix in the display unit D1, and the pixels 3 are arranged in a regular order. That is, in the display unit D1, the pixels 4R, the pixels 4G, and the pixels 4B are sequentially arranged from one end to the other end.

  As shown in FIG. 2, the pixel 4 includes a light emitting region R1 and a non-light emitting region R2 surrounding the light emitting region R1, and an organic EL element 5 capable of emitting light is provided in the light emitting region R1. ing. 2 is an enlarged plan view of a part of the display unit D1 in FIG.

  Each pixel 3 is provided with a partition wall 6. The partition wall 6 has a shape in which the lower section is narrower than the upper section, and is formed on an insulator 7 to be described later. As will be described later, a vapor deposition mask can be placed on the partition wall 6 in order to separate the layers constituting the organic EL element 5 by vapor deposition. The partition 6 is made of, for example, an inorganic insulating material such as silicon oxide, silicon nitride, or silicon oxynitride, or an organic insulating material such as phenol resin, novolac resin, acrylic resin, or polyimide resin. In addition, the thickness of the partition wall 6 is set to 1 μm or more and 4 μm or less.

  In addition, a sealing substrate 8 is formed on the element substrate 2 so as to face the element substrate 2. The sealing substrate 8 is made of a substrate that transmits light, and for example, glass or plastic can be used. In this embodiment, since the top emission type organic EL display emits light from the element substrate 2 side toward the sealing substrate 8 side, the light transmitting member is used for the sealing substrate 8.

  A protective film 9 is formed on the display portion D1 of the element substrate 2 so as to cover the pixels 4. By forming the protective film 9 so as to cover the partition wall 6, it is possible to reduce the ingress of oxygen or moisture into each pixel 4 and to suppress the deterioration of each pixel 4. The protective film 9 is made of an inorganic insulating material such as silicon nitride, silicon oxide, or silicon oxynitride. Further, the sealing substrate 8 is bonded onto the protective film 9 via the sealing material 10. The protective film 9 is set to have a thickness of 1 μm or more in order to suppress deterioration of each pixel 4.

The sealing material 10 has a function as an adhesive and can fix the element substrate 2 and the sealing substrate 8 by being cured. The sealing material 10 is made of a first polar substance, and for example, a photocurable resin such as an acrylic resin, an epoxy resin, a urethane resin, or a silicon resin, or a thermosetting resin can be used. In this embodiment, a photocurable epoxy resin that is cured by irradiation with ultraviolet rays is used. The sealing material 10 is made of an organic resin material, and the thickness is set to 1 μm or more in order to firmly bond the element substrate 2 and the sealing substrate 8. Regarding the transparency of the sealing material 10, the total light transmittance of light having a wavelength of 380 to 780 nm in the spectrophotometer is preferably 80% or more. Further, the moisture permeability of the sealing material 10 is preferably 150 (g / m ² · 24 h / 100 μm) or less according to JIS Z 0208, measured under the conditions of 85 ° C. and 85% RH. .

  Next, as shown in FIG. 3, various layers formed between the element substrate 2 and the sealing substrate 8 will be described. FIG. 3 is a cross-sectional view taken along the line AA in FIG.

  On the element substrate 2, a circuit layer 11 made of TFT, electric wiring, or the like is formed. Furthermore, an insulating layer 12 made of, for example, silicon nitride, silicon oxide, silicon oxynitride, or the like is formed on the circuit layer 11 so as not to cause an electrical short except for a predetermined region of the circuit layer 11.

  Further, a planarizing film 13 is formed on the insulating layer 12 in order to reduce surface irregularities caused by the circuit layer 11 and the insulating layer 12. Since the circuit layer 11 has a plurality of patterned electrical wirings, irregularities are formed on the surface thereof. When the organic EL element 5 is formed on an uneven surface, the electrode layers constituting the organic EL element 5 may be short-circuited and the organic EL element 5 may not emit light. Therefore, a planarizing film 13 is formed on the insulating layer 12.

  The planarizing film 13 can be made of an insulating organic material such as a novolac resin, an acrylic resin, an epoxy resin, or a silicon resin. The thickness of the planarizing film 13 is set to 2 μm or more and 5 μm or less, for example.

  Further, a contact hole S that penetrates the planarizing film 13 is formed in the planarizing film 13. The contact hole S is formed so that the lower part is narrower than the upper part. The contact hole S is formed in each pixel 4, and a part of the circuit layer 11 is exposed at the bottom of the contact hole S.

  FIG. 4 is a cross-sectional view for explaining the configuration of the organic EL element 5. An organic EL element 5 is formed on the planarization film 13 located in the light emitting region R1. As shown in FIGS. 3 and 4, the organic EL element 5 includes a first electrode layer 14, an organic light emitting layer 15 formed on the first electrode layer 14, and a second electrode formed on the organic light emitting layer 15. And an electrode layer 16. Here, the light emitting region R1 refers to a region that emits light when the first electrode layer 14 and the organic light emitting layer 15 are in direct contact with each other and a current flows between the first electrode layer 14 and the second electrode layer 16. .

  The first electrode layer 14 is formed on the planarization film 13. The first electrode layer 14 is made of a material having a high light reflectivity such as a metal such as aluminum, silver, copper, gold, rhodium or neodymium, or an alloy thereof. In this way, by configuring the first electrode layer 14 from a material having a high light reflectance, the light extraction efficiency can be improved in the top emission type organic EL element 5. The thickness of the first electrode layer 14 is set to, for example, 50 nm or more and 500 nm or less.

  A contact electrode layer 17 is formed from the planarizing film 13 to the inner peripheral surface of the contact hole S. A part of the contact electrode layer 17 formed on the inner peripheral surface of the contact hole S is connected to a part of the circuit layer 11 exposed from the bottom of the contact hole S.

  The insulator 7 is formed on the first electrode layer 14. The insulator 7 is a contact formed on the first electrode layer 14 so as to expose a part of the first electrode layer 14 corresponding to the light emitting region R1 and on the planarizing film 13 from the inner peripheral surface of the contact hole S. A part of the electrode layer 17 is exposed. The insulator 7 is made of, for example, an organic insulating material such as phenol resin, acrylic resin, or polyimide resin, or an inorganic insulating material such as silicon nitride, silicon oxide, or silicon oxynitride.

  Then, the organic light emitting layer 15 is formed on the first electrode layer 14 corresponding to the light emitting region R1, and the second electrode layer 16 is formed thereon.

  The organic light emitting layer 15 is formed on the first electrode layer 14 surrounded by the insulator 7 and is composed of a plurality of layers. In the present embodiment, the organic light emitting layer 15 has a configuration in which a hole injection layer 18, a hole transport layer 19, a light emitting layer 20, an electron transport layer 21, and an electron injection layer 22 are sequentially stacked. In addition, as a material constituting each layer of the organic light emitting layer 15, an appropriate material is selected according to the color of the emitted light.

  A second electrode layer 16 is formed on the organic light emitting layer 15. The second electrode layer 16 extends from the organic light emitting layer 15 to the insulator 7. Further, a part of the second electrode layer 16 is connected to a contact electrode layer 17 extending from the inner peripheral surface of the contact hole S to the planarizing film 13. Then, the second electrode layer 16 and the contact electrode layer 17 are conducted.

  The second electrode layer 16 is formed using a light-transmitting conductive material such as indium tin oxide (ITO) or tin oxide in order to extract light from the upper surface side of the organic light emitting layer 15. Moreover, when the 2nd electrode 16 consists of materials, such as magnesium, silver, aluminum, or calcium, for example, it can be set as a light transmissive electrode by making the thickness into 100 nm or less. Thus, the light emitted from the organic light emitting layer 15 is transmitted through the second electrode layer 16. Then, the transmitted light is emitted to the outside of the image display device 1.

  The organic light emitting layer 15 is excited and emits light when a current flows between the first electrode layer 14 and the second electrode layer 16 and holes and electrons injected into the organic light emitting layer 15 are combined. Then, the light emitted from the organic light emitting layer 15 resonates as a standing wave between the first electrode layer 14 and the second electrode layer 16, and the thickness of the organic light emitting layer 15 is adjusted in order to increase the emitted light. Has been.

  Here, the case where the organic light emitting layer 15 is an organic light emitting layer 15R that emits red light will be described.

  The hole injection layer 18R of the organic light emitting layer 15R is, for example, nickel oxide, titanium oxide, fluorocarbon, copper phthalocyanine (CuPc), 1,4,5,8,9,12-hexaazatriphenylene or cyano group It consists of a heterocyclic compound such as a derivative to which is bound. The thickness of the hole injection layer 18R is set to, for example, 5 nm or more and 40 nm or less.

  Further, the hole transport layer 19R of the organic light emitting layer 15R is formed of, for example, N, N′-bis (3-methylphenyl)-(1,1′-biphenyl) -4,4′-diamine (TPD), 4,4. Aromatic diamine compounds such as' -bis [N- (naphthyl) -N-phenyl-amino] biphenyl (α-NPD), and 4,4 ′, 4 ″ -tris (N- (3-methylphenyl) N— A starburst aromatic or aromatic amine compound such as phenylamino) triphenylamine (m-MTDATA) can be used, and the thickness of the hole transport layer 19R is set to, for example, 10 nm or more and 50 nm or less.

Further, the light emitting layer 20R of the organic light emitting layer 15R includes, for example, bis (2-methyl-8-quinolinolato) -4- (phenylphenolato) aluminum, 1,4-phenylenebis (triphenylsilane), 1,3-bis. Host materials such as (triphenylsilyl) benzene, 1,3,5-tri (9H-carbazol-9-yl) benzene, CBP, Alq ₃ or SDPVBi, tris (1-phenylisoquinolinato-C2, N) An organic metal compound such as iridium, or a material containing a dopant material such as DCJTB, coumarin, quinacridone, a perinone derivative having a phenanthrene group, an oligothiophene derivative, or a perylene derivative can be used. The thickness of the light emitting layer 20R is set to, for example, 20 nm or more and 40 nm or less.

Further, the electron transport layer 21R of the organic light emitting layer 15R is, for example, tris (8-quinolinolato) aluminum (Alq ₃ ), oxazole, oxadiazole, triazole, imidazole, imidazolone, stilbene derivative, pyrazoline derivative, tetrahydroimidazole, polyaryl Alkane and butadiene can be used. The thickness of the electron transport layer 21R is set to, for example, 20 nm or more and 60 nm or less.
Further, for example, lithium fluoride, cesium fluoride, carbon fluoride, or the like can be used for the electron injection layer 22R of the organic light emitting layer 15R. The thickness of the electron injection layer 22R is set to, for example, not less than 0.5 nm and not more than 2 nm.

  Next, the case where the organic light emitting layer 15 is an organic light emitting layer 15G that emits green will be described.

  The hole injection layer 18G of the organic light emitting layer 15G is, for example, nickel oxide, titanium oxide, fluorocarbon, copper phthalocyanine (CuPc), 1,4,5,8,9,12-hexaazatriphenylene or a cyano group. It consists of a heterocyclic compound such as a derivative to which is bonded. The thickness of the hole injection layer 18G is set to, for example, 5 nm or more and 40 nm or less.

  Further, the hole transport layer 19G of the organic light emitting layer 15G is formed of, for example, N, N′-bis (3-methylphenyl)-(1,1′-biphenyl) -4,4′-diamine (TPD), 4,4. Aromatic diamine compounds such as' -bis [N- (naphthyl) -N-phenyl-amino] biphenyl (α-NPD), and 4,4 ′, 4 ″ -tris (N- (3-methylphenyl) N— A starburst aromatic or aromatic amine compound such as phenylamino) triphenylamine (m-MTDATA) can be used, and the thickness of the hole transport layer 19G is set to, for example, 10 nm or more and 50 nm or less.

Further, the light emitting layer 20G of the organic light emitting layer 15G includes, for example, bis (2-methyl-8-quinolinolato) -4- (phenylphenolato) aluminum, 1,4-phenylenebis (triphenylsilane), 1,3-bis. (triphenylsilyl) benzene, 1,3,5-tri (9H-carbazol-9-yl) benzene, CBP, the host material, such as Alq ₃ or SDPVBi, or to these host materials, tris [pyridinyl -kN- Phenyl-kC] iridium and other organometallic compounds, or azomethine zinc complexes or bis [2- (2-benzoxazolyl) phenolato] zinc (II) and other metal complexes, or styrylamine, perlin, siloles having a benzene ring Derivatives, perinone derivatives with phenanthrene groups, oligothiophene derivatives, perylene derivatives What contains dopant materials, such as a body, can be used. The thickness of the light emitting layer 20G is set to, for example, 20 nm or more and 40 nm or less.

In addition, the electron transport layer 21G of the organic light emitting layer 15G includes, for example, tris (8-quinolinolato) aluminum (Alq ₃ ), oxazole, oxadiazole, triazole, imidazole, imidazolone, stilbene derivative, pyrazoline derivative, tetrahydroimidazole, polyarylalkane. Alternatively, butadiene can be used. The thickness of the electron transport layer 21G is set to, for example, 20 nm or more and 60 nm or less.
For example, lithium fluoride, cesium fluoride, carbon fluoride, or the like can be used for the electron injection layer 22G of the organic light emitting layer 15G. The thickness of the electron injection layer 22G is set to, for example, not less than 0.5 nm and not more than 2 nm.

  Next, the case where the organic light emitting layer 15 is an organic light emitting layer 15B that emits blue light will be described.

  The hole injection layer 18B of the organic light emitting layer 15B includes, for example, nickel oxide, titanium oxide, fluorocarbon, copper phthalocyanine (CuPc), 1,4,5,8,9,12-hexaazatriphenylene or a cyano group. It consists of a heterocyclic compound such as a derivative to which is bonded. The thickness of the hole injection layer 18B is set to, for example, 5 nm or more and 40 nm or less.

  Further, the hole transport layer 19B of the organic light emitting layer 15B is formed of, for example, N, N′-bis (3-methylphenyl)-(1,1′-biphenyl) -4,4′-diamine (TPD), 4,4. Aromatic diamine compounds such as' -bis [N- (naphthyl) -N-phenyl-amino] biphenyl (α-NPD), and 4,4 ′, 4 ″ -tris (N- (3-methylphenyl) N— A starburst aromatic or aromatic amine compound such as phenylamino) triphenylamine (m-MTDATA) can be used, and the thickness of the hole transport layer 19B is set to, for example, 10 nm or more and 50 nm or less.

  Further, the light emitting layer 20B of the organic light emitting layer 15B includes, for example, 1,4-phenylenebis (triphenylsilane), 1,3-bis (triphenylsilyl) benzene, 1,3,5-tri (9H-carbazole-9). -Yl) host materials such as benzene, CBP or SDPVBi, or styrylamine, perlin, cyclopentadiene derivatives, tetraphenylbutadiene, triphenylamine structures and vinyl groups bonded to these host materials, oxadiazole derivatives, A material containing a dopant material such as a pyrazoloquinoline derivative, a distyrylarylene derivative or a silole derivative having a benzene ring can be used. The thickness of the light emitting layer 20B is set to 20 nm or more and 40 nm or less, for example.

Further, the electron transport layer 21B of the organic light emitting layer 15B includes, for example, tris (8-quinolinolato) aluminum (Alq ₃ ), oxazole, oxadiazole, triazole, imidazole, imidazolone, stilbene derivative, pyrazoline derivative, tetrahydroimidazole, polyarylalkane. Alternatively, butadiene can be used. The thickness of the electron transport layer 21B is set to, for example, 20 nm or more and 60 nm or less.

  Moreover, for example, lithium fluoride, cesium fluoride, carbon fluoride, or the like can be used for the electron injection layer 22B of the organic light emitting layer 15B. The thickness of the electron injection layer 22B is set to, for example, not less than 0.5 nm and not more than 2 nm.

  As described above, depending on the color emitted by the organic light emitting layer 15, the film thickness of each layer constituting it varies. That is, the light emitting region of each pixel in the picture element contains a different light emitting material. In this way, by adjusting the film thickness between the electrodes, the light emitted from the organic light emitting layer 15 can be set to be a standing wave.

  A polar body 23 is formed between the element substrate 2 and the sealing substrate 8 so as to be in contact with at least a part of the sealing material 10. The polar body 23 is provided in connection with the sealing substrate 8, and the lower part is formed narrower than the upper part. The polar body 23 is curved at the end protruding from the sealing substrate 8 side toward the element substrate 2 side. As will be described later, after the polar body 23 is formed on the sealing substrate 8, when the sealing material 10 is applied on the sealing substrate 8 on which the polar body 23 is formed, the end of the polar body 23 is curved. Therefore, the flow of the sealing material 10 can be made difficult to be blocked, and bubbles can be prevented from being generated in the sealing material 10. Note that the polar body 23 is connected to the sealing substrate 8 means that the black matrix is interposed between the sealing substrate 8 and the polar body 23 when the sealing substrate 8 and the polar body 23 are directly connected. And the like, including both of which the sealing substrate 8 and the polar body 23 are indirectly connected.

  The polar body 23 is formed in a region that does not overlap the light emitting region R1 in plan view, and is disposed so as not to block light extracted from the light emitting region R1. And the polar body 23 is arrange | positioned so that it may be located in the area | region enclosed by the partition 6 by planar view. Furthermore, the height position of the lower part of the polar body 23 is set so as to be positioned below the height position of the upper part of the partition wall 6. Therefore, as will be described later, when the element substrate 2 and the sealing substrate 8 are bonded together via the sealing material 10, the partition wall 6 and the polar body 23 can be prevented from contacting each other. As a result, the distance between the element substrate 2 and the sealing substrate 8 can be shortened, and the thickness of the image display device 1 can be effectively reduced. The polar body 23 has a thickness in the vertical direction of 1 μm or more and 8 μm or less, and is set smaller than the thickness of the sealing material 10.

  The polar body 23 protrudes from the sealing substrate 8 side toward the element substrate 2 side, and the partition wall 6 protrudes from the element substrate 2 side toward the sealing substrate 8 side. Enters the sealing material 10 alternately from the upper side and the lower side. Then, by filling the region surrounded by the partition wall 6 with the sealing material 10, the contact area between the polar body 23 and the partition wall 6 with respect to the sealing material 10 can be increased, and the adhesive force thereof can be increased. . As a result, the adhesion between the element substrate 2 and the sealing substrate 8 can be improved satisfactorily.

  The polar body 23 has a function of adsorbing bubbles in the sealing material 10. The polar body 23 is made of a second polar substance, for example, a copolymer such as vinylidene fluoride, a photoresist material such as novolac resin, polyparahydroxystyrene, polynorbornene, or acrylic resin, or a thermosetting transparent epoxy. Low-polarity components consisting of monomers such as tetrafluoroethylene or hexafluoroethylene having a fluorinated alkyl group in the main component consisting of a thermosetting resin material such as resin, or alkali metal oxide or alkaline earth metal oxide It comprises subcomponents as highly polar components.

  Moreover, as a material of the high polarity component constituting the polar body 23, an organic aluminum compound such as aluminum oxide octylate, an alkylsilane derivative such as hexamethyldisilazane, an alkoxysilane compound or an ester of an alkoxysilane compound, etc. An organosilane compound can also be used. Further, as the material of the high polarity component constituting the polar body 23, γ-type activated alumina, barium oxide, calcium chloride, barium bromide, calcium bromide, zinc bromide, calcium sulfate, magnesium chloride, magnesium oxide, magnesium sulfate, Aluminum sulfate, sodium sulfate, sodium carbonate, potassium carbonate, zinc chloride, magnesium perchlorate, barium perchlorate, lithium perchlorate, sodium hydroxide, potassium hydroxide, copper chloride, cesium fluoride, niobium fluoride, odor Vanadium fluoride, molecular sieve or zeolite can be used. In addition, the polar body 23 may use 2 or more types of these materials together.

  Moreover, as a material of the highly polar component which comprises the polar body 23, metal alkoxides, such as a triisopropoxy aluminum, tetraethoxysilane, or tetra (n-butoxy) titanium, 2-methyl-2,4-pentanediol, diethanolamine Alternatively, an organometallic compound obtained by reacting with a polyol such as diethylene glycol can also be used.

  Here, the low polarity component means that the surface polarization is smaller than that of the bisphenol A type epoxy resin or the hydrophilicity is lower than that of the bisphenol A type epoxy resin. Further, the high polar component means that the surface polarization is larger than that of the bisphenol A type epoxy resin or the hydrophilicity is higher than that of the bisphenol A type epoxy resin. Here, the hydrophilicity can be measured by a known contact angle measurement method. Further, the polarization of the surface can be measured using a polarization measuring device using surface plasmon resonance.

  Temporarily, the material which comprises a polar body is made into a photocurable resin composition which has a novolak resin as a main component, for example, the material which comprises a sealing material is made into 100 mass parts of bisphenol A type epoxy resins, and polyethylene as a hardening control agent, for example. When a photocurable resin composition is prepared by mixing 10 parts by weight of glycol (molecular weight 1000) and 3 parts by weight of triphenylsulfonium borate salt as a photocationic polymerization initiator, the polar body is the same as the sealing material. It exhibits a degree of polarization and is also moderately hydrophilic. For this reason, the material constituting the polar body is composed mainly of a bisphenol A type epoxy resin, for example, by containing a minor component of an alkaline earth metal oxide that is a highly polar component in the main component of a novolac resin. The degree of polarization is significantly different from that of the sealing material 10, and the surface of the polar body 23 exhibits a property of repelling the sealing material 10. Then, rather than the entire surface of the polar body 23 being covered with the sealing material 10, at least a part of the surface of the polar body 23 is in contact with the bubbles, and the ratio of the surface of the polar body 23 that is covered with the sealing material 10 is higher. The lower the value, the more stable the state can be obtained. This is an effect caused by a difference in polarization state as well as a phenomenon in which oil in water is adsorbed by the oil absorbent and a phenomenon in which raindrops are repelled by a water-repellent resin.

  Once the bubbles in the sealing material 10 are in contact with the surface of the polar body 23, the interface between the surface of the polar body 23 and the bubbles is in a stable state. If the sealing material 10 enters the interface between the surface of the polar body 23 and the bubbles and the area of the interface decreases, an increase in energy is required, which is a disadvantageous process. Accordingly, the bubbles in the sealing material 10 are restrained by the surface of the polar body 23, and as a result, the polar body 23 can adsorb the bubbles in the sealing material 10.

  As described above, the polar body 23 contains a second polar substance different from the first polar substance constituting the sealing material 10, so that a part of the surface of the polar body 23 has a high polarity component of the second polar substance or Low polarity components can be exposed. And when it observes microscopically in the interface of the sealing material 10 and the polar body 23, both are going to leave | separate at a distance resulting from the difference in polarity of both. As a result, the bubbles contained in the uncured sealing material move so as to be adsorbed at the interface between them.

  The polar body 23 is provided along the outer periphery of the organic EL element 5. Since the polar body 23 can adsorb bubbles, the polar body 23 can be provided along the outer periphery of the organic EL element 5 to reduce bubbles remaining on the organic EL element 5 in plan view. Further, by reducing the number of bubbles on the organic EL element 5 located in the light emitting region R1, the possibility that the light emitted from the organic EL element 5 is refracted by the bubbles can be reduced, and the light extraction efficiency is improved. Can be made.

  A plurality of polar bodies 23 are provided along the outer periphery of the light emitting element 5. Since the polar body 23 is divided into a plurality of dots, as will be described later, when the sealing material 10 is applied onto the sealing substrate 8 on which the polar body 23 is formed, the flow of the sealing material 10 is smooth. And generation of bubbles in the sealing material 10 can be suppressed. Furthermore, when the polar bodies 23 are provided regularly and scattered along the outer periphery of the light emitting element 5, the flow of the sealing material 10 can be made smoother, and the bubbles in the sealing material 10 are further reduced. be able to.

  In addition, even if bubbles are generated in the sealing material 10, the polar body 23 is in the middle of the flow of the sealing material 10 when applied on the sealing substrate 8 on which the polar body 23 is formed. Can be adsorbed.

  In addition, bubbles b are adsorbed around the polar body 23 as shown in FIG. That is, the sealing material is formed at the interface with the polar body 23 via the gap. The bubbles b contain a small amount of oxygen, moisture, or the like, similar to the components in the atmosphere. When the state of direct contact with the organic EL element 5 becomes longer, the bubbles may oxidize the electrode of the organic EL element 5 or deteriorate the organic light emitting layer 15. Therefore, the polar body 23 adsorbs the bubbles b contained in the sealing material 10, so that it is possible to satisfactorily suppress changes in the characteristics of the organic EL element 5. The highly polar component preferably absorbs moisture or oxygen. In this case, since moisture or oxygen contained in the bubbles is removed, it is possible to more effectively suppress changes in the characteristics of the organic EL element 5.

  The size of the bubbles b is such that when the sealing material 10 is applied on the sealing substrate 8 on which the polar body 23 is formed, the bubbles in the sealing material 10 collide with the polar body 23 and the bubbles are finely decomposed. At this time, since the bubbles can be made small so that the size of the sealing material 10 is about 1/3 or less to 1/9 or less of the thickness of the sealing material 10, the bubbles are assumed to Even if it contacts directly, the influence which it has on the organic EL element 5 can be reduced. The diameter of the decomposed bubbles b is, for example, 1.5 μm or less.

Further, the bubble b is set so that there are more per unit volume in the sealing material 10 overlapping the non-light emitting region R2 in plan view than in the sealing material 10 overlapping the light emitting region R1 in plan view. Has been. Since the polar body 23 is arranged in the non-light emitting region R2 in a plan view, the density per unit volume of bubbles existing in the sealing material 10 can be adjusted, and the bubbles b are removed from the organic EL element 5. It is possible to reduce the obstacle to the extracted light. Here, the density per unit volume of the bubbles contained in the sealing material 10 is, for example, 0.2 or less in the region overlapping the light emitting region R1, and the region overlapping the non-light emitting region R2 is, for example, 0.6 or less. It is. In this embodiment, the unit volume is 1 μm ³ .

  Further, the density per unit volume of bubbles existing above the height position above the partition wall 6 is set larger than the density per unit volume of bubbles existing below the height position above the partition wall 6. That is, more bubbles exist around the upper part than the lower part of the polar body 23. As will be described later, when the sealing substrate 8 is bonded to the element substrate 2, the sealing substrate 8 is placed on the element substrate 2 from above the element substrate 2 with the element substrate 2 disposed below. Paste to. Therefore, the bubbles in the sealing material 10 can easily move toward the sealing substrate 8 positioned above by buoyancy, and a large amount of bubbles can be adsorbed on the top of the polar body 23. And the area | region where a bubble exists can be adjusted by providing the polar body 23 in the sealing substrate 8 while adjusting the direction which both board | substrates bond. Therefore, by collecting the bubbles on the sealing substrate 8 side so as to be away from the organic EL element 5, the opportunity for the bubbles and the organic EL element 5 to be in direct contact with each other can be reduced.

  According to this embodiment, by providing the sealing body with a polar body that adsorbs bubbles, the opportunity of direct contact between the bubbles and the organic EL element can be reduced, and the characteristics of the organic EL element can be effectively changed. Can be suppressed.

  Below, the manufacturing method of the image display apparatus 1 which concerns on embodiment of this invention is demonstrated in detail using FIGS.

  A preparation process for preparing the element substrate 2 and the sealing substrate 8 before the element substrate 2 and the sealing substrate 8 are bonded together via the sealing material 10 will be described.

  Here, the preparation process of the element substrate 2 will be described.

  First, a substrate formed by patterning the circuit layer 11 and the insulating layer 12 on the element substrate 2 is prepared. The circuit layer 11 and the insulating layer 12 are formed in a predetermined pattern by using a conventionally known thin film forming technique such as a vapor deposition method, a CVD method or a sputtering method, or a thin film processing technique such as a photolithography method or an etching method.

  Then, an organic resin film is formed using, for example, a conventionally known spin coating method so as to cover the circuit layer 11 and the insulating layer 12. Further, the organic resin film is exposed on the organic resin film using an exposure mask, and further developed and baked to expose a part of the circuit layer 11 as shown in FIG. A flattening film 13 having a contact hole S with a narrow lower portion is formed. The organic resin film becomes the planarizing film 13 after curing.

  Next, as shown in FIG. 5B, a first electrode layer 14 made of an alloy of, for example, aluminum and neodymium is formed on the planarizing film 13. Specifically, a metal film is formed on the planarizing film 13 and the through hole S using a sputtering method. Then, the first electrode layer 14 can be formed by patterning the metal film by an etching method or the like. At this time, together with the first electrode layer 14, the contact electrode layer 17 is formed from the inner peripheral surface of the contact hole S to the planarizing film 13. The first electrode layer 14 and the contact electrode layer 17 are simultaneously formed in the same process. Therefore, the first electrode layer 14 and the contact electrode layer 17 are made of the same material. Note that the first electrode layer 14 and the contact electrode layer 17 are separated from each other, and both are insulated from each other at this point.

  Next, an inorganic insulating material layer made of, for example, silicon nitride is formed on the first electrode layer 14 and the contact electrode layer 17 by using, for example, a CVD method. Then, as shown in FIG. 5C, the insulator 7 is formed by patterning the inorganic insulating material layer using a thin film processing technique. Specifically, the insulator is formed using a thin film processing technique such as a photolithography method or an etching method so that a part of the first electrode layer 14 and the contact electrode layer 17 in the region corresponding to the light emitting region R1 is exposed. The insulator 7 can be formed on each pixel.

  Further, as shown in FIG. 6A, a partition wall 6 having a lower width than the upper portion is formed on the insulator 7 by using a conventionally known thin film forming technique and thin film processing technique. At this time, the taper angle of the cross section of the partition wall 6 is preferably 55 degrees or more and 67 degrees or less.

  Then, as shown in FIG. 6B, the organic light emitting layer 15 is formed on the first electrode layer 14 by using, for example, a vapor deposition method. Specifically, when the organic light emitting layer 15 is formed, a vapor deposition mask is placed on the partition wall 6. Then, each pixel 4 can be separately coated with an organic material corresponding to a color that emits red, green, or blue.

  Then, as shown in FIG. 7A, the second electrode layer 16 is formed over the organic light emitting layer 15 and the insulator 7. When the second electrode layer 16 is configured, it can be formed from the organic light emitting layer 15 to the contact electrode layer 17 via the insulator 7 without using a vapor deposition mask. In this way, the organic EL element 5 can be formed in each pixel 4. Then, the second electrode layer 16 and the contact electrode layer 17 can be electrically connected by directly connecting the second electrode layer 16 and the contact electrode layer 17.

  Further, as shown in FIG. 7B, a protective film 9 is formed on the display portion D1 so as not to deteriorate the organic EL element 5 by using, for example, a sputtering method. By covering the organic EL element 5 with the protective film 9, it is possible to prevent the organic EL element 5 from being exposed from the outside air.

  Thus, the element substrate 2 on which various layers are formed can be prepared.

  Next, a preparation process for the sealing substrate 8 will be described.

First, as a material constituting the polar body 23 having the function of adsorbing bubbles, 0.5 to 40 parts by mass of a high polarity component is added to 100 parts by mass of the tetrafluoroethylene-hexafluoroethylene-vinylidene fluoride copolymer. The mixture containing is applied onto the sealing substrate 8 by using, for example, a spin coating method or a dispenser method. Here, as the high polarity component, for example, calcium oxide having a moisture absorption rate of 2 to 40% after standing for 1 hour in an atmosphere having a BET specific surface area of 3 to 150 g / m ² , a temperature of 25 ° C. and a relative humidity of 50%. Is used.

  Then, as shown in FIG. 8A, a polar body 23 protruding outward from the sealing substrate 8 side is formed by using a thin film processing technique such as a photolithography method or an etching method. The polar body 23 is formed so that the polar body 23 is regularly positioned in a region in the partition when the element substrate 2 and the sealing substrate 8 are bonded to each other.

  Then, the sealing substrate 8 is fixed downward so that the polar body 23 faces upward. Thereafter, an uncured sealing material 10x is applied onto the sealing substrate 8 on which the polar body 23 is formed, using, for example, a dispenser method or a screen printing method. At this time, since the polar bodies 23 are regularly arranged when the sealing material 10x flows on the sealing substrate 8, the flow of the sealing material 10x can be made smooth, and the thickness of the sealing material 10x can be increased. Therefore, the error can be kept within a predetermined range or less. Furthermore, when the sealing material 10x is applied, a small amount of mixed bubbles collide with the polar body 23 when the sealing material 10x flows, so that the bubbles are finely decomposed and easily adsorbed on the polar body 23. The viscosity of the sealing material 10x at 25 ° C. is set to 0.1 to 100 Pa · s.

  Thus, the sealing substrate 8 in a state where the sealing material 10x is applied can be prepared.

  Next, both the element substrate 2 and the sealing substrate 8 obtained by the process described above are prepared. Then, as shown in FIG. 9, the element substrate 2 is disposed on the lower side, and the sealing substrate 8 is disposed on the upper side. At this time, the polar body 23 turns the sealing substrate 8 upside down so as to face downward. Then, both substrates are aligned so that the polar body 23 is positioned in the partition wall 6 in plan view.

  Then, in a state where both are aligned, as shown in FIG. 10, the element substrate 2 and the sealing substrate 8 are bonded together via a sealing material 10x. At this time, the sealing material 10 x is deformed by the unevenness caused by the partition wall 6, and the bubbles b located around the polar body 23 can be moved toward the polar body 23. As a result, bubbles existing around the polar body 23 in the sealing material 10 x can be collected in the polar body 23.

  The operation of bonding the sealing substrate 8 to the element substrate 2 with the sealing material 10x is performed in an inert gas such as nitrogen gas or argon gas or in a high vacuum, for example, so that the element substrate 2 and the sealing substrate are bonded. It is possible to suppress oxygen and moisture from being contained between the two.

  Further, the sealing material 10x can be cured to fix both the element substrate 2 and the sealing substrate 8. Here, the sealing material 10x is cured to become the sealing material 10.

  In this way, an organic EL panel can be produced. Then, by mounting the mounting circuit 3 on the non-display area D2 of the element substrate 2, the image display device 1 can be manufactured.

  According to this embodiment, generation | occurrence | production of a bubble can be suppressed in a sealing material, and also the opportunity which the bubble generated in the sealing material and the organic EL element contact | connect directly can be reduced.

  In addition, this invention is not limited to the above-mentioned form, A various change, improvement, etc. are possible in the range which does not deviate from the summary of this invention. In the above-described embodiments, the top emission image display device has been described. However, a bottom emission image display device may be used as long as the effects of the present invention are achieved.

DESCRIPTION OF SYMBOLS 1 Image display apparatus 2 Element board | substrate 3 Mounting circuit 4 Pixel 5 Organic EL element 6 Partition 7 Insulator 8 Sealing board 9 Protective film 10 Sealing material 11 Circuit layer 12 Insulating layer 13 Planarization film 14 1st electrode layer 15 Organic light emitting layer 16 Second electrode layer 17 Contact electrode layer 18 Hole injection layer 19 Hole transport layer 20 Light emitting layer 21 Electron transport layer 22 Electron injection layer 23 Polar body D1 Display part D2 Mounting part R1 Light emitting area R2 Non-light emitting area S Contact hole b Bubbles

Claims (10)

A light emitting element formed on the element substrate;
A sealing substrate disposed opposite to the element substrate through a sealing material made of a first polar substance on the light emitting element;
A second polar substance that is formed between the element substrate and the sealing substrate so as to be in contact with at least a part of the sealing material in a region that does not overlap the light emitting element and has a surface different from the first polar substance A polar body consisting of
An image display device comprising: The image display device according to claim 1,
A plurality of the light emitting elements are provided on the element substrate, and each of the light emitting elements is surrounded by a partition wall protruding from the element substrate side toward the sealing substrate side, and in a region surrounded by the partition wall The image display device is filled with the sealing material. The image display device according to claim 2,
The image display apparatus, wherein the polar body is provided in a region surrounded by the partition wall. The image display device according to claim 3,
The image display apparatus according to claim 1, wherein a height position of a lower portion of the polar body is located below a height position of an upper portion of the partition wall. The image display device according to claim 4,
The bubbles are contained in the sealing material, and the density per unit volume of the bubbles present above the height position of the upper part of the partition wall is a unit of the bubbles existing below the height position of the upper part of the partition wall. An image display device characterized by being larger than the density per volume. The image display device according to claim 1,
The sealing material contains air bubbles,
An image display device, wherein a density per unit volume of bubbles contained in the sealing material is larger in a region not overlapping with the light emitting element than in a region overlapping with the light emitting element. The image display device according to any one of claims 1 to 6,
The image display apparatus, wherein the polar body is provided along an outer periphery of the light emitting element. The image display device according to claim 7,
An image display device, wherein a plurality of the polar bodies are provided along the outer periphery of the light emitting element. An image display device according to any one of claims 1 to 8,
The polar display is connected to the sealing substrate. An image display device according to any one of claims 1 to 9,
2. The image display device according to claim 1, wherein the polar body is narrower at the lower portion than at the upper portion, and a tip portion of the polar body that protrudes from the sealing substrate side toward the element substrate side is curved.

Images