JP2010244694A - Organic EL devices, electronic devices - Google Patents

Abstract

An organic EL device having high mechanical strength and excellent electrical characteristics is provided.
An organic EL device according to the present invention includes a first base material, a circuit layer provided on the first base material, and a plurality of organic EL elements provided on the circuit layer. The organic EL panel 2 includes the first substrate 10 having the thin film sealing layer 66 that seals the plurality of organic EL elements 60, and the circuit layer 64 is connected to the plurality of organic EL elements 60. The thin film sealing layer 66 includes a plurality of driving elements 15, and the thin film sealing layer 66 includes a resin layer 68 formed on the circuit layer 64 and an inorganic gas barrier layer 69 that covers the resin layer 68 and contacts the circuit layer 64. The first base material 10A is made of a glass substrate, and the thickness of the first base material 10A is 20 μm or more and 50 μm or less.
[Selection] Figure 4

Description

  The present invention relates to an organic EL device and an electronic device.

  Organic EL devices are expected to be applied to mobile phones, personal computers, in-vehicle monitors and the like as thin and light self-luminous elements. Recently, development of a flexible and high-functional organic EL device in which a high heat-resistant glass substrate is thinned to about 50 μm to 100 μm and a peripheral drive circuit is built (see Patent Document 1).

  However, the organic EL device using such a thin glass substrate has a problem that it is difficult to handle because it is weak against mechanical shock and is thin. Patent Document 2 proposes a liquid crystal device having a similar structure in which a liquid crystal panel using a thin glass substrate is reinforced with a thick polarizing plate of 0.3 mm and these are integrated with a laminate film. (See FIG. 7 of Patent Document 2).

JP 2008-58489 A Japanese Patent No. 4131639

  However, in such an organic EL device, when the glass substrate is too thin, defects called dimples and pits become obvious, and the glass substrate is easily broken by the pressure when the liquid crystal panel is sandwiched between laminate films.

  On the other hand, when the glass substrate is too thick, sufficient flexibility cannot be imparted and flexibility cannot be obtained, and the glass substrate is not easily deformed by the heat generated when the organic EL panel emits light. May adversely affect the drive elements that drive the.

  That is, in an organic EL panel using a thin glass substrate, an organic EL element is formed on a circuit layer on which driving elements such as TFTs are formed, and a thin film sealing layer for sealing the organic EL element is formed thereon. However, the thin film sealing layer is formed by a planarizing resin layer that planarizes the substrate surface and an inorganic gas barrier layer formed on the surface of the planarizing resin layer. As a result, the planarizing resin layer expands and compresses the driving element formed in the circuit layer.

  When a thin glass substrate is used, the pressure applied to such a driving element can be relaxed by bending the glass substrate. However, if the flexibility of the glass substrate is lowered, such an effect is obtained. There is a concern that the drive element may be damaged or the electrical characteristics of the drive element may be deteriorated. In particular, an organic EL panel covered with a laminate film is likely to accumulate heat during light emission, and therefore has a greater influence of thermal expansion than a normal organic EL panel, and special consideration is required.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an organic EL device and an electronic apparatus having high mechanical strength and excellent electrical characteristics.

  In order to solve the above problems, an organic EL device of the present invention includes a first base material, a circuit layer provided on the first base material, and a plurality of organic EL elements provided on the circuit layer. And an organic EL panel including a first substrate having a thin film sealing layer for sealing the plurality of organic EL elements, wherein the circuit layer is connected to the plurality of organic EL elements. The thin film sealing layer includes a resin layer formed on the circuit layer, and an inorganic gas barrier layer that covers the resin layer and contacts the circuit layer, the first substrate Is made of a glass substrate, and the thickness of the first base material is 20 μm or more and 50 μm or less.

  According to this configuration, since a glass substrate having a thickness of 20 μm or more and 50 μm or less is used as the base material of the first substrate of the organic EL panel, high flexibility equivalent to that of a resin substrate such as a plastic film is provided. It is possible to provide an organic EL device that can relieve the pressure applied to the drive element by the thermal expansion of the resin layer during light emission and stabilize the electrical characteristics of the drive element.

  That is, when the thickness of the first base material is thinner than 20 μm, defects called dimples and pits increase and light emission defects become remarkable. When the thickness is greater than 50 μm, sufficient flexibility cannot be imparted, and various resin layers formed on the first base material, for example, a planarizing resin layer covering an organic EL element, or a second substrate There is a concern that the sealing resin layer or the like filled in between may expand due to heat generated during light emission and press the driving element that drives the organic EL element. However, when the thickness is 20 μm or more and 50 μm or less, the number of light emission defects is one or less, and excellent light emission characteristics with almost no defects are obtained, and an organic EL device with a high yield can be provided.

  In the organic EL device of the present invention, the organic EL panel includes a sealing resin layer that covers the upper side of the plurality of organic EL elements, and a second substrate that is bonded to the first substrate via the sealing resin layer. The second substrate preferably includes a second base material made of a glass substrate having a thickness of 20 μm to 50 μm.

  According to this structure, high flexibility equivalent to resin substrates, such as a plastic film, can be provided, using the glass substrate which has low heat permeability as a 2nd base material and has the outstanding heat resistance. In addition, the influence of the thermal expansion of the planarizing resin layer and the sealing resin layer can be reduced not only on the first substrate but also on the second substrate. Therefore, an organic EL device having further excellent electrical characteristics can be provided.

  In the organic EL device of the present invention, the organic EL panel is disposed so as to sandwich the organic EL panel, and is in close contact with the organic EL panel directly or via an adhesive layer, and encloses the organic EL panel inside. It is desirable to further have a flexible film sheet.

  According to this configuration, an organic EL device having high mechanical strength and excellent sealing performance can be provided. In this case, if the thickness of the first substrate is too thin, the first substrate may be cracked by the pressure when the organic EL panel is sandwiched between the pair of film sheets, but the organic EL device of the present invention. Then, since the thickness of the first base material is not less than 20 μm and not more than 50 μm, cracks are hardly generated by such pressure, and an organic EL device with a high yield can be provided.

  In addition, in the configuration in which the organic EL panel is sealed between the pair of film sheets, heat at the time of light emission is hardly released to the outside, and the temperature of the organic EL panel may rise to nearly 100 ° C. Even if the thickness of the first substrate is 20 μm or more and 50 μm or less, the pressure applied to the drive element due to the thermal expansion of the resin layer during light emission can be relaxed, and the electrical characteristics of the drive element can be stabilized. An organic EL device can be provided.

  An electronic apparatus according to the present invention includes the above-described organic EL device according to the present invention.

  According to this configuration, an electronic device having high mechanical strength and excellent electrical characteristics can be provided.

1 is an exploded perspective view of an organic EL device according to an embodiment of the present invention. It is a top view of an organic EL device. It is sectional drawing which follows the AA 'line of FIG. It is sectional drawing of the organic electroluminescent apparatus which shows the detailed structure of an organic electroluminescent panel. It is explanatory drawing of the manufacturing method of an organic electroluminescent apparatus. It is explanatory drawing of the manufacturing method of an organic electroluminescent apparatus. It is explanatory drawing of the manufacturing method of an organic electroluminescent apparatus. It is explanatory drawing of the manufacturing method of an organic electroluminescent apparatus. It is a schematic diagram which shows a mode that an organic electroluminescent panel deform | transforms by the thermal expansion at the time of light emission. It is a figure which shows the relationship between the temperature of a display part, and the deformation amount of a board | substrate. It is a figure which shows the relationship between the thickness of a base material, and the generation number of a light emission defect. It is a schematic block diagram of the book type display which is an example of the electronic device of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. Such an embodiment shows one aspect of the present invention and does not limit the present invention. In the following embodiments, various shapes, combinations, and the like of the constituent members are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention. Moreover, in the following drawings, in order to make each structure easy to understand, an actual structure and a scale, a number, and the like in each structure are different.

  In the following description, an XYZ orthogonal coordinate system is set and the positional relationship of each member will be described. At this time, the predetermined direction in the horizontal plane is the X-axis direction, the direction orthogonal to the X-axis direction in the horizontal plane is the Y-axis direction, and the direction orthogonal to each of the X-axis direction and the Y-axis direction (that is, the vertical direction) is the Z-axis direction. And In this embodiment, the X-axis direction is the scanning line extending direction, the Y-axis direction is the data line extending direction, and the Z-axis direction is the viewing direction of the organic EL panel by the observer.

  FIG. 1 is an exploded perspective view of an organic EL device 1 according to an embodiment of the present invention. The organic EL device 1 includes an organic EL panel 2, a wiring substrate 3 (3A, 3B, 3C) connected to an end of the organic EL panel 2, and the organic EL panel 2 and the wiring substrate 3 sandwiched therebetween. And a sealing body 4 (first flexible sheet member 4A, second flexible sheet member 4B) to be held. It should be noted that the organic EL device 1 is provided with a frame and other accessory devices as necessary, but these are not shown in FIG.

  The organic EL panel 2 includes a first substrate 10 and a second substrate 20 that face each other. A sealing material 30 having a rectangular frame shape in plan view is provided on the peripheral edge of the facing region where the first substrate 10 and the second substrate 20 face each other. The first substrate 10 and the second substrate 20 are bonded to each other by a sealing material 30. A sealing resin is sealed in a space (cell gap) surrounded by the first substrate 10, the second substrate 20, and the sealing material 30.

  A display area Ad is provided inside the sealing material 30. In the display area Ad, a plurality of scanning lines 12 extending in the X-axis direction and a plurality of data lines 11 extending in the Y-axis direction are provided in a lattice shape in plan view. Sub-pixels corresponding to any one of red, green, and blue are provided at the intersections between the scanning lines 12 and the data lines 11. An organic EL element is formed in each sub-pixel, and emits one of red, green, and blue light. Such subpixels are arranged in a matrix on the first substrate 10, and a display region Ad is formed by the plurality of subpixels. Each sub-pixel is provided with a pixel switching element (driving element) such as a TFT (Thin Film Transistor), which is not shown in FIG.

  Scanning line drive circuits 13A and 13B are provided between the display area Ad and the sealing material 30. One scanning line drive circuit 13A, 13B is provided on each side of the display area Ad in the X direction. The scanning line driving circuits 13A and 13B are formed along the Y direction, and a plurality of scanning lines 12 extending from the display area Ad in the X direction are driven for either one of the left and right scanning lines. It is connected to either of the circuits 13A and 13B. The scanning line drive circuits 13A and 13B are integrally formed on the first substrate 10 together with the pixel switching elements provided in the display area Ad using the low temperature polysilicon technology.

  The first substrate 10 is provided with an overhang portion 10 c that protrudes to the outside of the second substrate 20. The overhanging portion 10c is provided with a plurality of terminal portions 19A, 19B, 19C each consisting of a plurality of external terminals. Of the terminal portions 19A, 19B, 19C, the terminal portion 19A provided at the center portion of the overhang portion 10c includes a plurality of external terminals each connected to the data line 11, and the terminal portions 19B provided on the left and right sides thereof. , 19C each include a plurality of external terminals connected to one of the pair of scanning line driving circuits 13A, 13B.

  One of a plurality of wiring boards 3A, 3B, 3C is connected to each of the terminal portions 19A, 19B, 19C via adhesives 7A, 7B, 7C. A semiconductor chip 6 which is a data line driving circuit is mounted on the wiring board 3A connected to the terminal portion 19A. As the adhesives 7A, 7B, and 7C, conductive adhesives such as ACF (Anisotropic Conductive Film) are used, but the external terminals of the wiring boards 3A, 3B, and 3C and the terminal portions 19A, 19B, In the case where one or both of the 19C external terminals are formed in a projecting shape and are brought into direct contact with each other for conduction, an insulating adhesive such as NCF (Non-Conductive Film) can be used. . As the protruding terminal, a bump electrode in which the surface of the resin core formed in a protruding shape is covered with a conductive film as described in JP-A-2006-196570 can be suitably used.

  In the case where NCF is used, if a translucent NCF is used, the wiring board 3A, 3B, 3C can be aligned with the external terminals of the terminal portions 19A, 19B, 19C. Since the planar overlap between the external terminals of 3A, 3B, and 3C and the external terminals of the terminal portions 19A, 19B, and 19C can be directly confirmed, alignment is facilitated and accuracy can be improved.

  On the outer surface side of the organic EL panel 2, a flexible sealing body 4 that is in close contact with the organic EL panel 2 and encloses the organic EL panel 2 inside is provided. The sealing body 4 includes a pair of first flexible sheet member 4A and second flexible sheet member 4B disposed so as to sandwich the organic EL panel 2 and the wiring boards 3A, 3B, 3C. Of the pair of first flexible sheet member 4A and second flexible sheet member 4B, at least the first flexible sheet member 4A arranged on the observation side is made of a transparent material.

  The first flexible sheet member 4A and the second flexible sheet member 4B are configured by flexible film sheets 41A and 41B in which adhesive layers 42A and 42B are formed on one surface side. As the resin constituting the adhesive layers 42A and 42B, various materials such as a thermoplastic resin, a thermosetting resin, and an ultraviolet curable resin can be used. In this embodiment, a thermoplastic resin is used. . A film sheet provided with an adhesive layer made of a thermoplastic resin is generally called a laminate film.

  The first flexible sheet member 4 </ b> A and the second flexible sheet member 4 </ b> B are each formed with a larger area than the organic EL panel 2. The first flexible sheet member 4A and the second flexible sheet member 4B are connected to the end portions (semiconductor chip 6) of the wiring boards 3A, 3B, 3C opposite to the side connected to the terminal portions 19A, 19B, 19C. Are exposed to the outside, and are bonded to each other by the adhesive layers 42A and 42B at the peripheral edge that is the outside of the organic EL panel 2.

  In addition, the front and back surfaces of the wiring boards 3A, 3B, 3C located at the peripheral edge of the organic EL panel 2, that is, the surfaces facing the first flexible sheet member 4A and the second flexible sheet member 4B are respectively bonded. Agent layers 8A, 8B, 8C, 9A, 9B, 9C are provided. The adhesive layers 8A, 8B, 8C, 9A, 9B, and 9C provided on the wiring boards 3A, 3B, and 3C, and the first flexible sheet member 4A and the second flexible sheet member 4B are provided. The first flexible sheet member 4A and the second flexible sheet member 4B and the wiring boards 3A, 3B, and 3C are bonded to each other using the adhesive layers 42A and 42B. For the adhesive layers 8A, 8B, 8C, 9A, 9B, 9C, various materials such as a thermoplastic resin, a thermosetting resin, and an ultraviolet curable resin can be used. A curable resin is used.

  FIG. 2 is a plan view of the organic EL device 1. The first flexible sheet member 4A (adhesive layer 42A) and the second flexible sheet member 4B (adhesive layer 42B) are disposed on the periphery of the organic EL panel 2 when viewed from the first flexible sheet member 4A side. ), And an adhesive portion 72 between the first flexible sheet member 4A (adhesive layer 42A) and the wiring substrates 3A, 3B, 3C (adhesive layers 8A, 8B, 8C). It is continuously formed with no gap along the four sides constituting the outer periphery of the panel 2. In addition, the second flexible sheet member 4B (adhesive layer 42B) and the wiring boards 3A, 3B, 3C (adhesive layer) are disposed on the periphery of the organic EL panel 2 when viewed from the second flexible sheet member 4B side. 9A, 9B, 9C) is provided at a position where the bonding portion overlaps the bonding portion 72. Further, a third sealing resin layer 43 is sealed in a space surrounded by the adhesive portions 71 and 72 and the sealing material 30 to seal the space. With such a configuration, the organic EL panel 2 is hermetically sealed inside the pair of first flexible sheet member 4A and second flexible sheet member 4B, that is, inside the sealing body 4.

  FIG. 3 is a cross-sectional view taken along line AA ′ of FIG. The first flexible sheet member 4A and the second flexible sheet member 4B are disposed in close contact with the main surface of the second substrate 20 and the main surface of the first substrate 10 of the organic EL panel 2, respectively. . The first flexible sheet member 4A and the second flexible sheet member 4B are curved at the end of the organic EL panel 2, and are in close contact with each other directly or via the wiring board 3A. The portion where the first flexible sheet member 4A and the second flexible sheet member 4B are in close contact with each other is bonded by the adhesive layer 42A and the adhesive layer 42B, and the first flexible sheet member 4A and the second flexible sheet member 4B are bonded. The portions where the flexible sheet member 4B and the wiring board 3A are in close contact are bonded by the adhesive layers 42A and 42B and the adhesive layers 8A and 9A.

  At the end of the organic EL panel 2, a gap between the organic EL panel 2 and the wiring board 3A and a gap 4H generated due to the shape of the end are formed. A first sealing resin layer 43 is provided in the gap 4H. The first sealing resin layer 43 covers the end surface of the first substrate 10, the end surface of the second substrate 20, and the end surface of the sealing material 30 so as to surround the entire outer periphery of the first substrate 10 and the second substrate 20. Is provided. Such a first sealing resin layer 43 is provided on the outer peripheral portion of the organic EL panel 2 so as to fill the gap 4H, whereby the end portion of the organic EL panel 2 is the first flexible sheet member. 4A, the second flexible sheet member 4B, the wiring substrate 3A, and the sealing resin layer 43 are sealed.

  Moreover, the 2nd sealing resin layer 44 is provided in the end surface of 4 A of 1st flexible sheet members, and the 2nd flexible sheet member 4B covering the boundary part of both. The second sealing resin layer 44 includes a boundary portion between the first flexible sheet member 4A and the second flexible sheet member 4B, and the first flexible sheet member 4A and the second flexible sheet member 4B. Covering each boundary portion with the wiring board 3 </ b> A, it is provided so as to surround the entire outer periphery of the sealing body 4. The first sealing resin layer 43, the first flexible sheet member 4A, the second flexible sheet member 4B, and the wiring board 3A cooperate to realize high sealing performance.

  The sealing resin layers 43 and 44 are formed, for example, by softening the adhesive layers 42A and 42B when the pair of first flexible sheet member 4A and second flexible sheet member 4B are heat-pressed. The film thickness of the adhesive layers 42A and 42B is set as described above, or the gap 4H and the end surfaces of the first flexible sheet member 4A and the second flexible sheet member 4B are positively filled with sealing resin. May be. For example, when the organic EL panel 2 is sandwiched between the first flexible sheet member 4A and the second flexible sheet member 4B, a sealing resin is disposed at the end of the organic EL panel 2, and the pair of first flexible sheet members 4A and the second flexible sheet member 4B spread the sealing resin so that the end of the organic EL panel 2 and the first flexible sheet member 4A and the second flexible sheet member 4B The sealing resin layer can be disposed at the boundary without a gap.

  FIG. 4 is a cross-sectional view showing a detailed configuration of the organic EL device 1. In the organic EL panel 2, the first substrate 10 and the second substrate 20 are arranged to face each other, and the first substrate 10 and the second substrate 20 are bonded and integrated through an adhesive layer 36.

  A plurality of organic EL elements 60 are formed on the first substrate 10. The organic EL element 60 has a configuration in which, for example, an organic light emitting layer 17 that generates white light is sandwiched between a first electrode 16 as an anode (pixel electrode) and a second electrode 18 as a cathode (common electrode). A thin film sealing layer 66 is formed on the first substrate 10 so as to cover the plurality of organic EL elements 60.

  The organic EL elements 60 are regularly arranged in a matrix on the first substrate 10 to form a display area Ad. The area outside the display area L is a non-display area. In addition, the organic EL element 60 uses three types of basic materials of R (red), G (green), and B (blue) properly, for example, three types of organic EL elements, for example, an organic EL element that generates red light, and a green color. An organic EL element that generates light or an organic EL element that generates blue light may be used.

  The first substrate 10 includes a first base material 10A. As the first base material 10A, an insulating substrate such as a glass substrate or a plastic substrate, or a conductive substrate such as a stainless steel plate or an aluminum plate can be used. The first base material 10A is given flexibility by reducing the thickness.

  In the present embodiment, an organic EL panel with a built-in peripheral drive circuit is manufactured using low-temperature polysilicon technology, and therefore a glass substrate having high heat resistance is used as the first base material 10A. In this case, the thickness of the first substrate 10A is 10 μm or more and 100 μm or less, preferably 20 μm or more and 50 μm or less, more preferably 20 μm or more and 40 μm or less.

  For example, when the thickness of the first base material 10A is thinner than 20 μm, defects called dimples and pits increase and light emission defects become remarkable.

  Further, when the thickness is greater than 50 μm, sufficient flexibility cannot be imparted to the first base material 10A, and various resin layers formed on the first base material 10A, for example, an organic buffer layer that covers the organic EL element 60 68 and the third sealing resin layer 35 filled between the second substrate 20 and the like may expand due to heat generated during light emission and press the pixel switching element 15 that drives the organic EL element 60. .

  When a glass substrate thinner than 50 μm is used, the pressure applied to the pixel switching element 15 can be relaxed by bending the glass substrate. However, when the flexibility of the glass substrate is reduced, such an effect is obtained. It may be difficult to obtain, and the drive element may be destroyed or the electrical characteristics of the drive element may be deteriorated. In particular, since the organic EL panel 2 covered with the first flexible sheet member 4A and the second flexible sheet member 4B is likely to accumulate heat during light emission, special consideration is given compared to a normal organic EL panel. Necessary.

  The applicant examined the relationship between the thickness of the glass substrate and the number of occurrences of light emitting defects in view of the particularity when the first flexible sheet member 4A and the second flexible sheet member 4B are used. . It was revealed that particularly good mechanical strength and electrical characteristics can be obtained when the thickness of the glass substrate is 20 μm or more and 50 μm or less.

  That is, when the thickness of the glass substrate is less than 20 μm, light emission defects due to the influence of dimples and the like increase, and when it exceeds 50 μm, the pixel switching element 15 such as a TFT is damaged or the electrical characteristics are deteriorated. When the thickness was 20 μm or more and 50 μm or less, the number of light emitting defects was 1 or less, and excellent light emitting characteristics with almost no defects were obtained. In the above thickness, the organic EL panel 2 is hardly cracked by the pressure when the organic EL panel 2 is sandwiched between the pair of first flexible sheet member 4A and second flexible sheet member 4B, and the organic EL panel has a high yield. Device 1 could be provided.

  As described above, by using a glass substrate having a thickness of 20 μm or more and 50 μm or less, the influence of heat during light emission as in the case where the first flexible sheet member 4A and the second flexible sheet member 4B are used. Even in the organic EL device 1 in which the above becomes remarkable, good mechanical strength and excellent electrical characteristics can be obtained.

A circuit layer 64 composed of the inorganic insulating layer 14 and the resin flattening layer 63 is formed on the first base material 10A. The inorganic insulating layer 14 is formed of a silicon compound such as silicon oxide (SiO ₂ ) or silicon nitride (SiN). On the inorganic insulating layer 14, a pixel switching element 15 composed of a plurality of thin film transistors (TFTs) corresponding to the plurality of organic EL elements 60 on a one-to-one basis, and a second electrode 18 connected to the second electrode 18 of the organic EL element 60. An electrode connection wiring 18A is formed. Further, the scanning line 12, the data line 12, the scanning line drive circuits 13A and 13B shown in FIG. 1, the power supply line for supplying current to the first electrode 16, and the like are also formed in this layer.

  On the inorganic insulating layer 14, a resin flattening layer 63 in which a metal reflective layer 62 made of an Al (aluminum) alloy or the like is provided is formed. The resin flattening layer 63 is formed of an insulating resin material such as a photosensitive acrylic resin or a cyclic olefin resin.

  A first electrode 16 (pixel electrode) of the organic EL element 60 is formed in a region overlapping the metal reflective layer 62 on the resin flattening layer 63 in a plane. The first electrode 16 is formed of a metal oxide such as ITO (Indium Tin Oxide) having a high hole injection property. The first electrode 16 is connected to the pixel switching element 15 on the first base material 10 </ b> A via a contact hole (not shown) that penetrates the resin planarization layer 63 and the inorganic insulating layer 14.

  An insulating partition layer 61 made of, for example, acrylic resin is formed on the resin flattening layer 63 (on the circuit layer 64) in order to partition the organic EL element 60. The partition wall layer 61 has a plurality of openings 61 </ b> H that expose the top of the first electrode 16.

  The organic light emitting layer 17 is formed so as to cover the upper surface of the partition layer 61 and the first electrode 16 along the uneven shape formed by the opening 61H and the partition layer 61.

  The organic light emitting layer 17 includes a light emitting layer that emits light when excited by recombination of holes and electrons injected by an electric field. The organic light emitting layer 17 may have a multilayer structure including layers other than the light emitting layer. As a layer other than the light emitting layer, a hole injection layer for facilitating injection of holes, a hole transport layer for facilitating transport of injected holes to the light emitting layer, and for facilitating injection of electrons. Examples include an electron injection layer and a layer that contributes to the recombination, such as an electron transport layer for easily transporting injected electrons to the light emitting layer.

  Examples of the light emitting layer of the organic light emitting layer 17 include a low molecular weight organic EL material or a high molecular weight organic EL material.

  The low molecular weight organic EL material has a relatively low molecular weight among organic compounds that emit light by being excited by recombination of holes and electrons. The high molecular weight organic EL material has a relatively high molecular weight among organic compounds that emit light when excited by recombination of holes and electrons.

  These low molecular weight organic EL materials or high molecular weight organic EL materials are substances corresponding to the color light (white light) emitted by the organic EL element 60. The material of the layer contributing to recombination in the light emitting layer is a substance corresponding to the material of the layer in contact with this layer.

  On the organic light emitting layer 17, the 2nd electrode 18 is formed so that the organic light emitting layer 17 may be covered along the uneven | corrugated shape. The second electrode 18 includes, for example, an electron injection buffer layer for facilitating injection of electrons into the organic light emitting layer 17 and a conductive layer having a low electrical resistance formed on the electron injection buffer layer.

  The electron injection buffer layer is made of, for example, LiF (lithium fluoride), Ca (calcium), or MgAg (magnesium-silver alloy). In addition, the conductive layer is a conductive layer with a small electrical resistance formed of a metal such as ITO or Al. The conductive layer may not be formed on the entire surface of the display region Ad. For example, a first conductive layer having a high transparency made of an alloy of Mg and Ag is formed on the entire surface of the display region Ad, and the low conductive layer made of Al or the like is formed. A second conductive layer having low resistance and low transparency may be formed in a stripe shape on the portion overlapping with the partition wall layer 61 as an auxiliary electrode.

  The second electrode 18 is connected to the second electrode connection wiring 18 </ b> A made of an inorganic conductive film such as Al formed in the peripheral portion (non-display region) of the display region Ad. The second electrode connection wiring 18A is connected to the terminal portions 19B and 19C (see FIG. 1) via a routing wiring (not shown). The second electrode connection wiring 18A is continuously formed along the three sides of the rectangular display area Ad (side where the terminal portion 19A shown in FIG. 1 is not formed).

  The second electrode 17 is connected to the second electrode connection wiring 12 that covers the entire surface of the display area Ad and surrounds the display area Ad. The second electrode 17 is a part of the partition wall layer 61 that forms the outermost periphery, that is, a part that surrounds the outer side of the organic light emitting layer 17 at the outermost peripheral position (hereinafter also referred to as an enclosing member). The second electrode 18 is formed on the outside of the plurality of organic EL elements 60 provided in the display region Ad together with the surrounding member. It is sealed. In particular, since the organic EL element 60 is formed on the inorganic insulating layer 14 and the outer peripheral portion of the second electrode 18 is in contact with the inorganic insulating layer 14, all of the bottom surface, top surface, and side surfaces of the plurality of organic EL elements 60. Is covered with an inorganic film, and high sealing performance is realized.

  A thin film sealing layer 66 that covers the inorganic insulating layer 14, the resin flattening layer 63, and the second electrode 18 of the organic EL element 60 is formed on the second electrode 18. The thin film sealing layer 66 covers the entire portion of the second electrode 17 exposed on the circuit layer 64 and is in contact with the inorganic insulating layer 14, and a portion formed in at least the display region Ad of the electrode protective layer 67. An organic buffer layer (flattening resin layer) 68 that covers the organic buffer layer 68 and an inorganic gas barrier layer 69 that covers the entire portion of the organic buffer layer 68 exposed on the circuit layer 64 and is in contact with the electrode protective layer 67 or the inorganic insulating layer 14. ing.

  The electrode protective layer 67 is made of a non-base material, for example, a silicon compound such as silicon oxynitride (SiON).

  The organic buffer layer 68 is formed so as to fill the uneven shape formed by the partition wall layer 61 and the opening 61H, and the unevenness on the circuit layer 64 is flattened. Further, it is in close contact with the inorganic gas barrier layer 69 and has a buffering function against mechanical impact. As a material constituting the organic buffer layer 68, for example, a highly transparent resin with low moisture permeability such as an epoxy compound can be used.

  The inorganic gas barrier layer 69 is formed of a non-base material, in particular, for example, SiON in consideration of translucency, gas barrier properties, and water resistance.

  The thin film sealing layer 66 functions together with the second electrode 17 as a sealing member for preventing moisture and oxygen from entering the organic EL element from the outside. Of the thin-film sealing layer 66, the inorganic gas barrier layer 69 is formed on a surface flattened by the organic buffer layer 67, and has better step coverage than the electrode protective layer 67, and a high sealing function is obtained. In particular, since the mechanical shock is relieved by the organic buffer layer 68, cracks and the like are hardly generated, and excellent sealing performance can be maintained over a long period of time.

  In addition, since the inorganic gas barrier layer 69 is in contact with the inorganic insulating layer 14 directly or through the electrode protective layer 67 that is an inorganic film, moisture and oxygen enter from the interface between the inorganic gas barrier layer 69 and the inorganic insulating layer 14. There is little concern. Therefore, extremely high sealing performance can be realized in cooperation with the second electrode 17 that is also formed in contact with the inorganic insulating layer 14.

  The second substrate 20 is disposed on the surface of the first substrate 10 on which the thin film sealing layer 66 is formed. The second substrate 20 is bonded to the thin film sealing layer 66 on the first substrate 10 via the adhesive layer 36.

  The second substrate 20 includes a second base material 20A made of a light transmissive material such as a transparent glass substrate or a transparent plastic substrate. In the present embodiment, in order to improve the sealing performance by the second substrate 20, a glass substrate having a lower moisture permeability than a plastic substrate is used, and the flexibility is given by thinning the glass substrate. In this case, the thickness of the second substrate 20A is 10 μm or more and 100 μm or less, preferably 20 μm or more and 50 μm or less, and more preferably 20 μm or more and 40 μm or less.

  A color filter layer 21 is formed on the surface of the second substrate 20A facing the first substrate 10. The color filter layer 21 has a configuration in which the red coloring layer 22R, the green coloring layer 22G, and the blue coloring layer 22B are regularly arranged in a matrix corresponding to the red subpixel, the green subpixel, and the blue subpixel, respectively. . In addition, the color filter layer 21 includes a black matrix layer (light-shielding layer) 23 in a region surrounding each colored layer 22R, 22G, and 22B, more specifically in a region corresponding to the partition wall layer 61. As a material constituting the black matrix layer 23, for example, Cr (chromium) or the like can be used.

  The colored layers 22R, 22G, and 22B are disposed so as to overlap the white organic light emitting layer 17 formed on the first electrode 16 in a planar manner. Thereby, the light emitted from the plurality of organic light emitting layers 17 passes through the corresponding colored layers 22R, 22G, and 22B, and is emitted to the viewer side as each color light of red light, green light, and blue light. It is like that.

  The color filter layer 21 includes an overcoat layer 24 that covers the colored layers 22R, 22G, and 22B and the black matrix layer 23, and an inorganic gas barrier layer 25 that covers the overcoat layer 24.

  The overcoat layer 24 extends from the inside of the display area Ad to the vicinity of the formation area of the sealing material 30 around the non-display area. The overcoat layer 24 is formed of a resin material such as acrylic or polyimide. The inorganic gas barrier layer 25 is formed of a non-base material, for example, a silicon compound such as silicon oxynitride (SiON).

  The adhesive layer 36 includes a sealing material 30 that is formed in a frame shape along the outer periphery of the second substrate 20, and a third sealing resin layer 35 that is filled in a region within the frame of the sealing material 30 without a gap. ing.

  The third sealing resin layer 35 is provided between the first substrate 10 and the second substrate 20 and covers at least a portion of the thin film sealing layer 66 corresponding to the display region Ad. As a material of the third sealing resin layer 35, for example, a low-elasticity resin in which an isocyanate is added as a curing agent to a urethane resin or an acrylic resin can be used.

  The sealing material 30 is provided in the non-display area so as to surround the third sealing resin layer 35 between the first substrate 10 and the second substrate 20. As the material of the sealing material 30, a material having a low moisture permeability, for example, a highly adhesive adhesive in which an acid anhydride is added as a curing agent to an epoxy resin and a silane coupling agent is added as an accelerator is used. it can.

  The second flexible sheet member 4B and the first flexible sheet member 4A are in close contact with the outer surfaces of the first substrate 10A and the second substrate 20A, respectively.

  In the case of this embodiment, the total thickness of each member from the surface of the thin film sealing layer 66 to the surface of the first flexible sheet member 4 </ b> A in close contact with the second substrate 20, and the first electrode 16 of the organic EL element 60. Is designed so that the total thickness of each member from the portion in contact with the circuit layer 64 to the surface of the second flexible sheet member 4B in close contact with the first substrate 10 is equal to each other.

  The term “thickness” as used herein refers to the thickness located at the center of the subpixel, and the center of the subpixel refers to the first electrode 16, the organic light emitting layer 17, and the second electrode in each organic EL element 60. 18 denotes the central portion of a region overlapping each other when viewed from the normal direction (Z direction) of the first base material 10A, that is, the central portion of the light emitting region of the organic EL element 60.

  Specifically, the thickness of the second flexible sheet member 4B is W1, the thickness of the first base material 10A is W2, the thickness of the circuit layer 64 is W3, the thickness of the first flexible sheet member 4A is W4, 2 When the thickness of the substrate 20A is W5, the thickness of the color filter layer 21 is W6, and the thickness of the third sealing resin layer 35 interposed between the color filter layer 21 and the thin film sealing layer 66 is W7, W1 The sum T1 of W2 and W3 is designed to be equal to the sum T2 of W4, W5, W6 and W7.

  In this case, the light emitting element portion 65 formed by the plurality of organic EL elements 60 formed on the circuit layer 64 and the thin film sealing layer 66 formed on the surface thereof is paired with the organic EL panel 2. The first flexible sheet member 4 </ b> A and the second flexible sheet member 4 </ b> B are arranged at a substantially central portion in the thickness direction (Z direction) of the display module. Therefore, when a stress in the bending direction is applied to the display body joule, the stress is uniformly distributed to the upper layer side and the lower layer side of the light emitting element portion 65, and the stress applied to the light emitting element portion 65 itself is suppressed to the minimum. Therefore, the light emission characteristics hardly change with respect to bending, and stable light emission characteristics can be maintained.

  The “thickness” of each member located at the center of each sub-pixel should be controlled uniformly for all the sub-pixels. The thicknesses W1 to W7 may be measured for all the sub-pixels that substantially contribute to the display (in the sense of excluding the above), and the average thickness may be set to the thicknesses W1 to W7. In this case, the “average thickness” is not only an average value but also an average after excluding a portion with large variation, that is, a portion exceeding the allowable variation range in consideration of statistical variation. It goes without saying that the thickness may be set to the above W1 to W7.

  5-8 is explanatory drawing of the manufacturing method of the organic electroluminescent apparatus 1. FIG. 5-8, in the manufacturing method of the organic EL device 1, the organic EL panel 2 and the wiring boards 3A, 3B, 3C are integrated with the first flexible sheet member 4A and the second flexible sheet member 4B. The process will be described mainly. The following description will be given with reference to FIG.

  First, as shown in FIG. 5, the wiring boards 3A, 3B, 3C are connected to the end portions of the organic EL panel 2 that is made flexible by thinning the glass substrate, and the organic EL panel 2 and the wiring boards 3A, 3B are connected. , 3C is disposed between the first flexible sheet member 4A and the second flexible sheet member 4B. As a method for producing the organic EL panel 2 using a thin glass substrate, known methods described in Patent Documents 1 and 2 can be used.

  Next, as shown in FIG. 6, the laminate is placed between a pair of pressure rollers 81 and 82 from an end of the organic EL panel 2 opposite to the side to which the wiring boards 3A, 3B, and 3C are connected. insert. Then, the adhesive layers 42A, 42B and the adhesive layers 8A, 8B, 8C, 9A, 9B, 9C are interposed on the mutually opposing surfaces of the first flexible sheet member 4A and the second flexible sheet member 4B. The first flexible sheet member 4A and the second flexible sheet member 4B are connected to a part of the wiring boards 3A, 3B, 3C (ends opposite to the side connected to the terminal portions 19A, 19B, 19C). The laminated body is pressed while being heated by a pair of pressure rollers 81 and 82 in a state of being exposed to the outside.

  Then, the adhesive layers 42A, 42B and the adhesive layers 8A, 8B, 8C, 9A, 9B, 9C are used as the first flexible sheet member 4A, the second flexible sheet member 4B, the organic EL panel 2, and the wiring board 3A. , 3B, and 3C, the gap 4H is pushed and expanded to seal the gap 4H, and the first flexible sheet member 4A and the second flexible sheet are formed at the periphery of the organic EL panel 2. The adhesive layers 42A and 42B and the adhesive layer 42A, the part where the member 4B opposes, and the part where the first flexible sheet member 4A and the second flexible sheet member 4B oppose the wiring boards 3A, 3B, and 3C. Adhesive layers 8A, 8B, 8C, 9A, 9B, and 9C are used for adhesion, and the organic EL panel 2 is sealed inside the first flexible sheet member 4A and the second flexible sheet member 4B.

  In this step, the adhesive layers 42A and 42B and the adhesive layers 8A, 8B, 8C, 9A, 9B, and 9C are partly attached to the outside of the first flexible sheet member 4A and the second flexible sheet member 4B. A second sealing resin layer 44 that seals the boundary between the first flexible sheet member 4A and the second flexible sheet member 4B is formed on the end surfaces of the first flexible sheet member 4A and the second flexible sheet member 4B.

  7A and 7B, the first flexible sheet member 4A and the second flexible sheet member 4B are advanced along the conveying direction of the pressure rollers 81 and 82, and the first flexible sheet member 4A and the second flexible sheet member 4B are advanced. It is a figure which shows the state which adhere | attached to the edge part by the side of the wiring board 3A, 3B, 3C of the adhesive sheet member 4B. In this state, the peripheral portion of the organic EL panel 2 includes the first flexible sheet member 4A, the second flexible sheet member 4B, the wiring boards 3A, 3B, 3C, the adhesive layers 42A, 42B, and the adhesive layer 8A. , 8B, 8C, 9A, 9B, and 9C are hermetically sealed inside the pair of first flexible sheet member 4A and second flexible sheet member 4B. Further, a part of the adhesive layers 42A and 42B and the adhesive layers 8A, 8B, 8C, 9A, 9B, and 9C flows, and the first and second flexible sheet members 4A and 4B and the organic EL. By filling the gap between the panel 2 and the periphery of the organic EL panel 2 is sealed.

  Thus, the organic EL device 1 is completed. When the sealing step shown in FIGS. 6 and 7 is completed, as shown in FIG. 8, the pressure roller is rotated in the reverse direction, and the organic EL device 1 is taken out in the direction opposite to the loading direction.

  In the above manufacturing method, the pair of pressure rollers 81 and 82 is used as the pair of pressure means for pressing the laminated body. However, the pressure means is not limited to this, and various types of pressure can be applied. Pressure means can be used. For example, flat pressure members may be arranged on both sides of the laminate, and the laminate may be pressed between them. Further, the reason why the pressure was applied while being heated by the pressure rollers 81 and 82 was that a thermoplastic or thermosetting adhesive was used as the adhesive layers 42A, 42B, 8A, 8B, 8C, 9A, 9B, 9C. However, when an ultraviolet curable adhesive layer is used as the adhesive layers 42A, 42B, 8A, 8B, 8C, 9A, 9B, 9C, no heat treatment is required.

  Further, in the manufacturing method described above, the adhesive layers 42A, 42B, 8A, 8B, 8C, 9A, 9B, and 9C are previously formed on the film sheets 41A and 41B and the wiring boards 3A, 3B, and 3C, and then the pressure treatment is performed. However, the film sheets 41A and 41B may be bonded together while applying or dropping an adhesive between the film sheets 41A and 41B. A bright display is possible by directly adhering the film sheets 41A and 41B and the organic EL panel 2 without the adhesive layers 42A and 42B.

  According to the organic EL device 1 and the manufacturing method thereof of the present embodiment described above, the glass substrate having a thickness of 20 μm or more and 50 μm or less as the base material 10A, 20A of the first substrate 10 and the second substrate 20 of the organic EL panel 2. Therefore, the organic EL panel 2 is sandwiched between the pair of first flexible sheet member 4A and second flexible sheet member 4B while providing high flexibility equivalent to that of a resin substrate such as a plastic film. It is difficult to break even against mechanical shock at the time, and the pressure applied to the pixel switching element 15 due to thermal expansion of the planarizing resin layer 68 and the third sealing resin layer 35 during light emission is relieved, and the pixel switching element 15 It is possible to provide the organic EL device 1 capable of stabilizing the electrical characteristics.

  FIG. 9 shows that stress due to thermal expansion of the planarizing resin layer 68 and the third sealing resin layer 35 when the organic EL panel 2 emits light is relieved by deformation of the first base material 10A and the second base material 20A. It is a schematic diagram for demonstrating. In FIG. 9, only the configuration necessary for the description is shown, and is illustrated more simply than the cross-sectional view illustrated in FIG. 4.

  In FIG. 9, the thickness of the first base material 10A and the second base material 20A is not less than 20 μm and not more than 50 μm. The glass substrate having this thickness has high flexibility (flexibility), and the stress applied to the circuit layer 64 when the flattening resin layer 68 and the third sealing resin layer 35 are expanded by heat at the time of light emission. Can be relaxed by deformation.

  That is, when the organic EL panel 2 emits light, the heat causes various resin layers included in the organic EL panel 2, for example, the planarizing resin layer 68 covering the organic EL element 60, the first substrate 10 </ b> A, and the first substrate 10 </ b> A. The third sealing resin layer 35 or the like filled between the two base materials 20A expands due to heat during light emission and presses the circuit layer 64. This pressure may squeeze a driving element such as a pixel switching element included in the circuit layer 64 to deteriorate its electrical characteristics.

  The temperature of the organic EL panel 2 is not so high if the heat generated by the light emission is easily released to the outside. However, in the structure where the organic EL panel is covered with the flexible sheet member, the heat generated in the organic EL panel. Are not easily released to the outside and are likely to accumulate inside. Therefore, the thermal expansion force of the planarizing resin layer 68 and the third sealing resin layer 35 is also increased, and the pressure on the circuit layer 64 is also increased.

  In the organic EL device of the present embodiment, the base materials 10A and 20A are very thin, thereby having high flexibility. Therefore, the pressure applied to the circuit layer 64 is 10A. 20A can be relieved by deformation. Therefore, in spite of the structure in which the heat is easily trapped inside the organic EL panel 2, the electric characteristics of the drive element are hardly deteriorated, and stable display characteristics can be obtained even if light is emitted for a long time. Become.

  FIG. 10 is an explanatory diagram for explaining the relationship between the temperature of the display unit during light emission and the amount of deformation of the base material. In FIG. 10, the horizontal axis represents the temperature of the organic EL panel display unit, and the vertical axis represents the amount of displacement in the thickness direction of the display unit of the organic EL panel.

  For example, when a glass substrate having a thickness of 500 μm is used as the base material, even if the temperature of the display unit reaches 100 ° C., the variation in the thickness of the organic EL panel is about 0.4 μm, and the base material is hardly deformed. On the other hand, when a glass substrate having a thickness of 40 μm is used as the base material, the variation in the thickness of the organic EL panel is 4 μm when the temperature of the display unit reaches 100 ° C., and the base material is greatly deformed. I understand that.

The temperature of the display unit varies depending on the light emission luminance of the display unit. When the light emission luminance increases, the temperature of the display portion increases. For example, when the light emission luminance of the display portion is 465 cd / cm ² , the temperature of the display portion is 100 ° C. The emission luminance of 465 cd / cm ² is required for in-vehicle displays, but such emission luminance is expected to increase in the future for personal computer monitors, portable electronic paper, etc. But it is fully envisioned.

  FIG. 11 is a diagram illustrating the relationship between the thickness of the base material and the number of light emitting defects. As shown in FIG. 11, when the thickness of the base material is thinner than 20 μm, defects called dimples and pits increase and light emission defects become remarkable. Further, when the thickness of the base material is greater than 50 μm, various resin layers formed on the base material, for example, a planarizing resin layer covering the organic EL element, or between the first base material and the second base material The filled sealing resin layer or the like expands due to heat at the time of light emission, and presses the driving element that drives the organic EL element. Therefore, a large number of light emission defects occur. Further, when such a thick substrate is used, sufficient flexibility cannot be imparted to the substrate, and the substrate is damaged by the pressure when the organic EL panel is sandwiched between the pair of flexible sheet members. It becomes easy.

  On the other hand, in the region where the thickness of the substrate is 20 μm or more and 50 μm or less, the number of emission defects is 1 or less, and excellent emission characteristics with almost no defects are obtained. An organic EL device having a high yield can be provided with almost no cracking caused by the pressure when sandwiched between the flexible sheet members.

  FIG. 12 is a schematic configuration diagram of a book-type display 1000 which is an example of an electronic apparatus including the organic EL device 1 (1A, 1B). 12A is a perspective view of the display 1000, and FIG. 12B is a schematic cross-sectional view showing the configuration of the connector portion of the electronic display.

  The display 1000 is a book-type display using the organic EL device 1 (1A, 1B) as electronic paper. The display 1000 is provided with a hinge portion 1001 having a connector 1002 that can be connected to the wiring board 3 of the electronic paper 1A, 1B at a portion corresponding to a book binding margin. A connector 1002 is attached to the hinge portion 1001 so as to be rotatable about a rotation axis Ax. By rotating the connector 1002, the electronic paper 1A, 1B is turned so as to turn a normal paper. .

  A plurality of electronic papers 1A and 1B may be detachably connected to the hinge portion 1001. As a result, the necessary number of electronic papers can be removed and carried as in a loose leaf.

  The organic EL device of the present invention is not limited to the book type display described above, and can be mounted on various electronic devices. Examples of such electronic devices include personal computers, digital still cameras, viewfinder type or monitor direct view type digital video cameras, car navigation systems, in-vehicle displays, pagers, electronic notebooks, calculators, word processors, workstations, videophones, POSs. There are terminals, devices equipped with a touch panel, and the like, and the organic EL device can be suitably used as these display means. Furthermore, the organic EL device of the present invention can also be used as a light source for an exposure head of a device other than a display device, for example, a printer head.

DESCRIPTION OF SYMBOLS 1 ... Organic EL apparatus, 2 ... Organic EL panel, 4 ... Sealing body, 4A, 4B ... Flexible sheet member, 10 ... 1st board | substrate, 10A ... 1st base material, 15 ... Pixel switching element (drive element) 20 ... 2nd substrate, 20A ... 2nd base material, 35 ... 3rd sealing resin layer, 41A, 41B ... Film sheet, 60 ... Organic EL element, 64 ... Circuit layer, 66 ... Thin film sealing layer, 68 ... Organic buffer layer (flattened resin layer), 69 ... inorganic gas barrier layer, 1000 ... book-type display (electronic equipment)

Claims (4)

A first substrate; a circuit layer provided on the first substrate; a plurality of organic EL elements provided on the circuit layer; and a thin film sealing layer for sealing the plurality of organic EL elements; And an organic EL panel including a first substrate having
The circuit layer includes a plurality of driving elements connected to the plurality of organic EL elements,
The thin film sealing layer includes a resin layer formed on the circuit layer, and an inorganic gas barrier layer that covers the top of the resin layer and contacts the circuit layer,
The organic EL device according to claim 1, wherein the first base material is formed of a glass substrate, and the thickness of the first base material is 20 μm or more and 50 μm or less. The organic EL panel has a sealing resin layer that covers the top of the plurality of organic EL elements, and a second substrate bonded to the first substrate via the sealing resin layer,
The organic EL device according to claim 1, wherein the second substrate includes a second base material made of a glass substrate having a thickness of 20 μm to 50 μm.   The organic EL panel further includes a pair of flexible film sheets that are disposed so as to sandwich the organic EL panel, and are in close contact with the organic EL panel directly or via an adhesive layer and encapsulate the organic EL panel inside. The organic EL device according to claim 1 or 2.   An electronic apparatus comprising the organic EL device according to claim 1.

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