JPWO2006022273A1 - Organic EL element, protective film for organic EL element and method for producing the same - Google Patents

Abstract

Equipped with a microlens array that can be integrated with the cap, it is possible to concentrate light emission from both sides of the organic EL layer on one side, and a protective film with high transparency is possible, so effective light emission per power consumption In particular, a top-emission type organic EL device having an increased number of dots is provided. An organic EL element comprising a protective film, an organic EL light emitting diode (OLED) including a transparent electrode film, an organic EL layer, and a counter electrode layer, a substrate on which the OLED is mounted, and a cap provided so as to cover the OLED A microlens array made of, for example, a silicone resin on the outer surface or inner surface of the cap or on the surface side of the transparent electrode film, preferably a light reflecting surface on the substrate, and more preferably the protective film is silica. Including a film and a silicon-containing organic fluoropolymer film.

Description

  The present invention relates to an organic EL element, and more particularly to an organic EL element that effectively exhibits high light emission efficiency in the case of a top emission type.

Organic electroluminescence elements (hereinafter referred to as “organic EL elements” for short) have become possible to form high-purity, high-quality laminated films with a thickness of nm class due to recent advances in thin film formation technology, and have a thickness of about 5V. Low voltage operation is possible.
In this way, organic EL elements are attracting attention as elements for next-generation display systems that have low power consumption, high quality, are thin, and can display curved surfaces.

In an organic EL element, a plurality of films composed of predetermined organic molecular components are stacked one above the other to form an organic EL layer, and an electrode layer is attached to each of the upper and lower sides to form an OLED (organic light emitting diode). A phenomenon in which light is emitted when electrons and holes are recombined by applying a predetermined voltage or current to inject electrons and holes into the organic EL layer is used.
Accordingly, in order to guide the emitted light to the outside and perform the display function, at least one of the electrodes provided on the upper and lower sides must be transparent.

  As this transparent electrode, ITO (indium tin oxide) is widely used as a material capable of achieving both electrical conductivity and transparency, but in general, annealing is required to reduce the electrical resistance of ITO, and Polishing is necessary to increase the smoothness of the ITO surface (to reduce the roughness).

Since the organic EL layer is deteriorated when the temperature is increased during the annealing of ITO or the like, it is necessary to perform the formation of the ITO prior to the formation of the organic EL layer.
That is, when ITO is formed first, the stacking order is [substrate-first electrode film (ITO) -organic EL layer-second electrode film (opaque electrode film)], and light is emitted from the substrate side (bottom emission). For this reason, the substrate must be transparent, and a glass substrate is usually used.

  However, the glass substrate has poor thermal conductivity, and the heat dissipation during operation is insufficient to dissipate heat, resulting in a high temperature and easily deteriorating the organic EL layer.

Furthermore, in order to obtain a high-speed and high-definition display system, it is necessary to drive the active matrix (TFT). In that case, since the TFT transistor must be formed between the substrate and the ITO electrode, the presence of the TFT transistor As a result, the aperture ratio decreases, and the external conversion efficiency of light emission decreases.
That is, in order to ensure the required amount of light emission, the power consumption increases, and accordingly, the amount of heat generated in proportion to the power consumption increases, resulting in a higher temperature, and the organic EL layer is more likely to deteriorate.

Therefore, a method of making the second electrode transparent to be [substrate-TFT-first electrode-organic EL layer-second electrode (ITO)] and emitting light from the opposite side of the substrate (top emission) has been studied.
In that case, it is necessary to pay particular attention not to alter the organic EL layer when forming the ITO.
For example, Non-Patent Document 1 discloses a device for manufacturing such as bonding a substrate on which an organic EL layer is formed and a substrate on which a second electrode (ITO) is formed in order to prevent this alteration.
Kathleen M.M. Vaeth, Information Display 6/03 (2003), pp12-17, SID.

Now, the emission intensity of the organic light emitting diode (OLED) is maximum in the direction perpendicular to the organic EL layer, but is also dispersed in other directions, and the relative value is theoretically from the perpendicular direction. It is a function of θ represented by cos θ where the angle is θ.
Therefore, when the emitted light is condensed in a right angle direction, the luminance can be increased. That is, in order to obtain a constant luminance in the right angle direction, the power consumption may be suppressed and the deterioration of the organic EL layer can be prevented.

Therefore, in order to achieve the condensing of this OLED, introduction of various microlens arrays has been studied.
For example, Patent Literature 1 discloses a technique including a lens layer formed by sealing the transparent electrode 6 with a glass substrate (glass cap) 7 and ion implantation from the outer surface side.

  In Patent Document 2, a gas barrier layer 11 and a silicon oxide film 13 are formed on an organic film 10, and an ultraviolet curable resin mixed with fine transparent beads is applied thereon, and a microlens 12 is formed using a roll mold. Subsequently, a technique for laminating and bonding to a separately formed organic EL substrate is disclosed.

  Patent Document 3 discloses a technique in which a microlens array 17 preferably made of a photocurable transparent resin is further provided on the protective film 16 on the anode 15 of the organic EL pixel.

As described above, although the positions where the microlens array is formed are various, the formation method uses ion implantation for glass or ultraviolet curable resin or photocurable resin, and stable and inexpensive manufacturing such as ensuring transparency. It is not easy to get conditions.
JP 2003-264059 A JP 2003-257627 A Japanese Patent Laid-Open No. 2004-039500

Further, it should be noted that the organic EL layer itself emits light from both sides with an intensity according to the function cos θ, that is, not only from the surface on the transparent electrode film side of interest but also from the opposite side. There is the same amount of light emission.
In the conventional technique, light emission from the opposite surface side is obstructed by the opaque electrode film regardless of bottom emission and top emission, and the ratio of light emission / power consumption cannot be increased.

Non-Patent Document 2 specifically discloses a technique for forming an organic EL element having a transparent electrode film on both surfaces of an organic EL layer on a glass substrate, and it has become possible to use double-sided light emission. As an application of the organic EL element, light reception (viewing) on only one side is dominant, and the ratio of the light emission amount / power consumption in that case still cannot be increased.
Transparent organic light emitting devices, G.M. Gu et al. , Appl. Phys. Letter. 68 (19), 6 May 1996

The organic EL element formed in this way is left as it is, and the OLED, in particular, the organic EL layer and the ITO film are deteriorated and deteriorated over time by moisture and oxygen. Therefore, some kind of protective film is indispensable, and top emission type In some cases, the protective film must be as transparent as possible to visible light.
Furthermore, a low-temperature process is required so that the OLED is not physically and chemically altered again when forming the protective film.

  Conventionally, a silicon nitride-based film is optimal as a protective film (passivation) against moisture and oxygen for silicon semiconductors and the like, but a silicon nitride-based film generally requires a high temperature during film formation and is hard. Various approaches have been made because it was inappropriate by itself, such as applying stress to the organic EL element.

For example, a technology for obtaining a high-purity silica (SiO ₂ ) film by simply dissolving polysilazane, in particular PHPS (PerHydroPolySilazane), in an organic solvent, and baking it has been put into practical use in the semiconductor industry. As a result of this advancement, it has become possible to perform firing at a relatively low temperature of 100 ° C. or lower, which makes it possible to apply to organic EL elements.

However, the silica film formed by firing the polysilazane forms a dense protective film macroscopically, but microscopically, it is not as dense as the silicon nitride film, and the protective ability alone is inferior.
Therefore, an attempt has been made to obtain a required protective capability by forming a multilayer film by combining polysilazane and other types of films.

  For example, Patent Document 4 discloses a technique in which an intermediate film (polysilazane film) is sandwiched between silicon nitride films from above and below, the OLED is covered, only the outer peripheral portion is laser-heated, and the intermediate film is converted to silica.

Attempts have also been made to apply a fluorine polymer film to a part of the multilayer film.
Fluorine has the highest electronegativity and the strongest bond with carbon in the polymer skeleton, so fluorine-based polymer membranes are generally robust, hydrophobic, and oleophobic, that is, exhibit water repellency and antifouling properties. It is.

  For example, Patent Document 5 lists four layers of a fluoropolymer film, a silicon nitride film, an epoxy polymer film, PET, or a fluorine polymer film as an example of a four-layer transparent protective film. A different structure is disclosed.

However, these composite films have complicated manufacturing procedures and are expensive. In particular, when a silicon nitride film is used as a part of the multilayer film, it is not always easy to obtain the required protection capability without altering the OLED. is not.
Further, the adhesion between the inorganic film and the organic polymer film, particularly the fluorine polymer film, is not always ensured, and the protective ability may be deteriorated by peeling.
Moreover, in the case of these multilayer films, transparency was not necessarily ensured.
JP 2004-119138 A JP 2004-139991 A

  In order to solve the above-described problems, an object of the present invention is to provide an organic EL element including a microlens array that can be manufactured stably and inexpensively.

  Another object of the present invention is to provide an organic EL element that can be manufactured more stably and inexpensively by integrating a cap and a microlens array.

  Another object of the present invention is to provide an organic EL element that can be manufactured more stably and inexpensively by providing a reliable method for bonding a cap and a substrate.

  Another object of the present invention is to provide an organic EL device that can be manufactured more stably and inexpensively by simultaneously realizing and sealing the protection of the organic EL device and the reliable adhesion of the cap and the substrate. .

  In order to solve the above-described problems, an object of the present invention is to provide an organic EL element in which the light emission / power consumption ratio is increased by concentrating light emission from both surfaces of the organic EL layer on one surface. To do.

  Another object of the present invention is to provide an organic EL device that can stably and inexpensively produce a mechanism that concentrates light emission from both sides of an organic EL layer on one side by using a metal substrate as a substrate.

  In order to solve the above problems, the present invention has a simple structure and manufacturing method, and there is no fear that the organic EL layer is deteriorated or deteriorated, and transparency is ensured. Therefore, in particular, a top emission type organic EL element. An object is to provide a suitable protective film and a method for producing the same.

  To achieve the above object, an organic EL device according to the present invention includes an organic EL light emitting diode (OLED) including a transparent electrode film, an organic EL layer, and a counter electrode layer, and the OLED as described in claim 1. In an organic EL element including a substrate and a cap provided so as to cover the OLED and facing the transparent electrode film, the outer surface or the inner surface of the cap or the surface side of the transparent electrode film And a microlens array.

  According to a second aspect of the present invention, the cap is made of silicone resin, and the microlens is formed integrally with the cap.

  According to a third aspect of the present invention, when the cap and the substrate are bonded, a primer treatment is performed on the bonded portion of the substrate with the cap.

  Further, as described in claim 4, the organic EL light emitting diode (OLED) including a transparent electrode film, an organic EL layer, and a counter electrode layer, a substrate on which the OLED is mounted, and the OLED are provided so as to cover the OLED. An organic EL element including a cap having a transparent portion facing the transparent electrode film, wherein a microlens array is provided integrally with the cap on the outer surface or inner surface of the cap, and the inner surface of the cap and the upper surface of the OLED And a gap between the upper surface of the substrate including a gap between the bonding surface of the cap and the substrate is filled with silicone resin.

  According to a fifth aspect of the present invention, when the cap and the substrate are bonded, primer treatment is performed on both the bonded portion of the substrate and the bonded portion of the cap.

  In addition, as described in claim 6, the silicone resin is polydimethylsiloxane (Poly-Di-Methyl-Siloxane, PDMS).

  In order to achieve the above object, an organic EL device according to the present invention includes an organic EL light emitting diode (OLED) including a first transparent electrode film, an organic EL layer, and a second transparent electrode film as described in claim 7. An organic EL element including an OLED comprising: a substrate on which the OLED is mounted so that the first transparent electrode film is in contact with the substrate; and a light reflecting surface is provided on a side of the substrate on which the OLED is mounted. To do.

  According to the present invention, light emitted from the organic EL layer that has passed through the first transparent electrode film as in the conventional case is directly emitted to the outside, and in addition to this, the light that has passed through the second transparent electrode film Since the light is reflected by the light reflecting surface provided on the substrate and superimposed on the first transparent electrode film and emitted to the outside, the ratio of the amount of emitted light to the outside / power consumption can be substantially doubled.

  According to an eighth aspect of the present invention, the substrate is a metal substrate made of, for example, magnesium, aluminum, or an alloy containing them, and having an insulating film formed on the surface thereof.

The metal substrate can be used as a light reflecting surface simply by finishing the surface smoothly so as to be a mirror surface.
In particular, a magnesium substrate can be easily mirror-finished, and a high-quality light reflecting surface can be obtained at a low cost.
These metal substrates, particularly magnesium substrates, are rich in workability and can be manufactured inexpensively because a strong and thin insulating film can be easily formed by surface oxidation. On top of that, the thermal conductivity is large and heat dissipation of power consumption is high. However, the organic EL device according to the present invention can be provided with these characteristics.

  According to a ninth aspect of the present invention, the light reflecting surface includes a concave mirror array including a plurality of concave mirrors.

  The concave mirror array to be provided on the substrate according to the present invention, particularly in the case of a metal substrate, surface is oxidized in advance after the surface of the original substrate is finished into a concave array shape by molding, grinding, or pressing, and the concave portion is made of silicone or the like. It can be easily prepared by filling the transparent resin and flattening the final surface.

  The size and pitch of each concave mirror capture and reflect as much lateral light emission as possible, so that the OLED size (hereinafter referred to as d) and pitch (hereinafter referred to as D, D> d) is set equal to D. In other words, it is desirable to line up the OLEDs in a one-to-one correspondence without gaps.

The planar shape of each concave mirror is usually a circle, but may be a square or a rectangle that matches the vertical and horizontal pitches of the OLEDs in order to increase the amount of light collected.
The focal length (hereinafter referred to as f1) of each concave mirror is preferably approximately 0.5 times to 2 times the pitch D of the OLED.
The distance between the concave mirror array and the OLED (hereinafter referred to as s1) is preferably approximately 0.5 times to 2 times the focal length f1 of the concave mirror.
In general, the cross-sectional shape of each concave mirror is preferably a parabola.

  The details of the above parameters are such that the reflected light is attenuated by the passing medium, the distortion due to various aberrations of the concave mirror, the interference with the light emission of the adjacent OLED, etc. so that the reflected light can be focused at maximum in the direction perpendicular to the organic EL element surface. Is determined in consideration of

  In addition, as described in claim 10, a cap is further provided so as to cover the OLED, and a portion facing the second transparent electrode film is transparent, and is provided on an outer surface or an inner surface of the cap, or the first A microlens array comprising a plurality of microlenses is provided on the surface side of the second transparent electrode film.

According to the present invention, the microlens array to be provided on the cap side, that is, close to the first electrode film, can be provided by various methods.
In particular, stable performance including sealing of the cap and the substrate can be obtained at a low cost by integrally molding with the cap using, for example, silicone resin.

  The size and pitch of each microlens captures and reflects as much lateral light as possible, and therefore is equal to D out of the OLED size (hereinafter referred to as d) and pitch (hereinafter referred to as D, D> d). That is, it is desirable that the OLEDs are arranged in a one-to-one correspondence without gaps.

The planar shape of each microlens is usually circular, but it may be square or rectangular according to the vertical and horizontal pitches of the OLEDs in order to increase the amount of light collected.
The focal length (hereinafter referred to as f2) of each microlens is preferably approximately 0.5 times or more and 2 times or less of the pitch D of the OLED.
The distance between the microlens and the OLED (hereinafter referred to as s2) is preferably approximately 0.5 times or more and 2 times or less of the focal length f2 of the microlens.
The cross-sectional shape of each microlens is preferably a parabola.

  The details of the above parameters are such that the refracted light can be condensed in the direction perpendicular to the surface of the organic EL element so that the light is attenuated by the passing medium, the distortion caused by various aberrations of the microlens, and the interference with the light emission of the adjacent OLED. Determined in consideration of

  In order to achieve the above object, the protective film of the organic EL device according to the present invention is a silica film obtained by firing polysilazane (PHPS) and a silicon-containing organic fluorine laminated thereon, as described in claim 11. The silicon-containing organic fluoropolymer includes a polymer film, and the silicon-containing organic fluorine polymer film includes a perfluorohydrocarbon part, a hydrocarbon part, and a silicon-containing group.

  In addition, as described in claim 12, the perfluorohydrocarbon part is composed of a perfluoroalkane or a perfluoroalkene having only a straight chain or a side chain.

  In addition, as described in claim 13, the perfluorohydrocarbon portion is composed of a perfluoropolyether (perfluoropolyoctacene) which is only a straight chain or has a side chain and includes only a saturated bond or an unsaturated bond. It is characterized by that.

  Further, as described in claim 14, the hydrocarbon portion includes only a saturated bond, is only a straight chain or has a side chain, and at least one of hydrogen atoms is substituted with the silicon-containing group. Features.

  In addition, as described in claim 15, one or more of the hydrogen atoms are further substituted with halogen.

  In addition, according to claim 16, in the silicon-containing group, one or a plurality of hydrogen atoms are substituted with an alkoxyl group or a halogen in a silane composed of one or a plurality of linear silicon. It is characterized by.

In order to achieve the above object, a method for producing a protective film of an organic EL element according to the present invention is as described in claim 17.
Diluting polysilazane (PHPS) with a cyclohexane solvent to obtain a polysilazane solution to which a predetermined metal catalyst is added;
Applying the polysilazane solution on the ITO film of the organic EL element;
Forming a silica film by humidifying and drying at a predetermined temperature of 20 ° C. to 100 ° C. and a predetermined humidity for a predetermined time;
Diluting a silicon-containing organofluorine polymer composed of a perfluorohydrocarbon part, a hydrocarbon part, and a silicon-containing group with perfluorohexane to obtain a solution of the silicon-containing organofluorine polymer;
Applying the silicon-containing organofluorine polymer solution onto the silica film;
And humidifying and drying at a predetermined temperature of 20 ° C. or higher and 100 ° C. or lower for a predetermined time to bond the silicon-containing organic fluorine-based polymer to a silicon atom of silica at a molecular level. It is characterized by that.

  Since the organic EL device according to the present invention includes a microlens array made of a silicone resin that can be manufactured stably and inexpensively, consumption is increased by increasing the luminance in a direction perpendicular to the light emitting surface and deteriorating the organic EL layer. An increase in power can be suppressed.

  In addition, the organic EL element according to the present invention can be manufactured more stably and inexpensively because the cap and the microlens array are integrally formed.

  In addition, the organic EL device according to the present invention can be manufactured more stably and inexpensively because the sealing treatment can be performed firmly by applying a primer treatment to the substrate when the cap made of silicone resin is bonded to the substrate.

  In addition, since the organic EL device according to the present invention is sealed and protected by a silicone resin that can be cured at a low temperature simultaneously with the adhesion between the cap and the substrate, it can be manufactured stably and inexpensively without deterioration.

  The organic EL device according to the present invention can emit light from both sides of the OLED to the outside by the light reflecting surface provided on the substrate, so that the light emission amount, and hence the light emission amount / power consumption ratio can be substantially doubled. In addition, an increase in power consumption that causes deterioration of the organic EL layer can be suppressed.

  In addition, the organic EL device according to the present invention can be manufactured stably and inexpensively by integrally forming the light reflecting surface using a metal substrate such as magnesium as the substrate.

  In addition, the organic EL device according to the present invention is combined with the light reflecting surface provided on the first transparent electrode film side and / or the microlens provided on the second electrode film side, that is, the cap side, so that the organic EL device surface is provided. Since the maximum light condensing can be performed in a perpendicular direction, the ratio of the effective light emission amount / power consumption as the display device can be further increased.

  The protective film of the organic EL device according to the present invention is rich in water repellency and oil repellency comprising two layers of a dense silica film and a silicon-containing organic fluoropolymer film firmly bonded to the silica film at a molecular level. A protective film can be provided to protect fragile organic EL devices (OLEDs and their drive circuits) during the manufacturing process and during storage or use after manufacturing with respect to moisture, oxygen, high temperature, and physical impact. In particular, a top emission type organic EL element can be provided economically with high reliability.

  In addition, according to the method for manufacturing a protective film for an organic EL device according to the present invention, an organic EL device (OLED and its driving circuit) that is vulnerable to moisture, oxygen, high temperature, and physical blow is physically or chemically. Forming a protective film rich in water repellency and oil repellency consisting of two layers of a dense silica film and a silicon-containing organic fluoropolymer film firmly bonded to the silica film at a molecular level without being damaged. A highly reliable and economical manufacturing method can be provided.

(A), (B), (C) is a cross-sectional schematic diagram which shows the organic EL element in Example 1, 2, and 3, respectively. (A), (B), (C) is a cross-sectional schematic diagram which shows the organic EL element in Example 4, 5, and 6, respectively. These are the cross-sectional schematic diagrams which show the organic EL element in Example 7. These are the cross-sectional schematic diagrams which show the structure of the organic EL element in Example 8. FIG. These are the cross-sectional schematic diagrams which show the structure of the organic EL element in Example 9. FIG. These are the cross-sectional schematic diagrams which show the structure of the organic EL element in Example 10. FIG. These are the cross-sectional schematic diagrams which show the structure of the organic EL element in Example 11. FIG. These are the optical equivalent sectional drawings of the organic EL element in Example 8. These are the distribution diagrams of the emitted light amount of the organic EL element in Example 8. FIG. These are the optical equivalent sectional drawings of the organic EL element in Example 9. FIG. These are the distribution diagrams of the emitted light amount of the organic EL element in Example 9. FIG. These are the optical equivalent sectional drawings of the organic EL element in Example 10. FIG. These are the distribution diagrams of the emitted light amount of the organic EL element in Example 10. FIG. These are the cross-sectional schematic diagrams of the organic EL element which concerns on Examples 12-15 of this invention. These are the schematic diagrams which show the molecular structure of the protective film of the organic electroluminescent layer element in Example 12. FIG. These are the schematic diagrams which show the molecular structure of the protective film of the organic electroluminescent layer element in Example 13. FIG. These are the molecular structure schematic diagrams which show the various aspects of the silicon containing organic fluorine-containing polymer which concerns on Examples 12-15 of this invention. These are the flowcharts which show the formation procedure of the protective film of the organic EL layer in Example 15.

Explanation of symbols

11, 12, 13, 14, 15, 16 Ray 21, 22, 23, 24, 25, 26 Ray 51, 52, 53, 54, 55, 56 Ray 61, 62, 63, 64, 65, 66 Ray 71, 76 light beam 100 cap 102 lower surface of cap 110 micro lens array 115 micro lens 105 leg portion of cap 120 adhesive portion 130 filling portion 200 substrate 201 metal substrate (magnesium substrate)
205 boundary (light reflecting surface)
215 Transparent layer 210, 225 Insulating film 220 Polysilicon layer or amorphous silicon layer (TFT layer)
230 Pixel drive unit (TFT transistor circuit)
231 Source 233 Source wiring 235 Drain 237 Gate insulating film 239 Gate wiring 240 Electrode for cathode (first electrode)
250R, 250G, 250B Organic EL layer 260 Transparent electrode film (second electrode)
270 Protective film 300, 301, 302 Organic EL layer 305 Mirror image 310 First transparent electrode film (drain wiring)
320 Second transparent electrode film 322 Mg-Ag layer 401 Boundary 410 Silica film obtained by baking polysilazane 420 Silicon-containing organic fluorine-based polymer film 430, 440, 450 Main part of silicon-containing organic fluorine-based polymer 432 Perfluoroalkane Part 434, 454 Hydrocarbon part 439, 459 Silicon-containing group 442 Perfluoropolyoxetane part 490, 490a, 490b Dirt

Hereinafter, embodiments according to the present invention will be specifically described with reference to the drawings in the case of a top emission type and an active matrix driving type.
The present invention can be applied to a bottom emission type or a passive matrix drive type as long as it is appropriately modified.

  1A, 1B, and 1C are schematic cross-sectional views showing organic EL elements in Examples 1, 2, and 3, respectively. FIGS. 2A, 2B, and 2C are respectively implemented. FIG. 3 is a cross-sectional view showing the organic EL element in Example 7, and FIG.

  Referring to FIG. 1A, a cross-sectional schematic view showing an organic EL element according to the present invention, wherein the organic EL element body is formed on a substrate 200 and covered with a transparent cap 100 made of, for example, glass, The leg 105 extended downward at the edge of the cap is sealed by being bonded to the substrate 200 via the bonding portion 120 and is blocked from the outside.

  The organic EL element body is composed of an organic EL light emitting diode (OLED) for one panel and a corresponding pixel driving unit 230. For example, a polysilicon layer or an amorphous silicon layer 220 is deposited on the upper surface of the substrate 200 to drive the pixel. A unit 230 is formed.

  Each pixel driving unit 230 is basically composed of one TFT transistor, and its gate and source are connected to driving wirings (not shown) in rows and columns, respectively, and its drain (if necessary) (Via a conductive metal layer) and connected to the cathode electrode 240 of the OLED.

  Each OLED is composed of the transparent electrode film 260 common to the cathode electrode 240 and the organic EL layers 250R, 250G, or 250B corresponding to the three primary colors sandwiched between the two electrodes, on the transparent electrode film 260. A protective film 270 is formed.

In this way, the organic EL element body is formed.
When a predetermined signal voltage that changes with time is applied to the pixel drive unit of the organic EL element body after the sealing is completed, the OLED emits light of three primary colors having a light amount that changes in accordance with the signal voltage.
The three primary color lights are emitted from the upper side through the transparent electrode film 260, the protective film 270, and the transparent cap 100, and each pixel has a desired color tone and functions as a display device.

  Now, according to the present invention, the microlens array 110 made of silicone resin is adhered to the inner surface of the cap 100, and each microlens 115 has a convex lens shape and faces the upper surface of the OLED.

The light emission intensity of each OLED depends on the light emission angle as described above. In FIG. 1A, the vertical upper direction is maximized, and the angle from the vertical upper direction is proportional to cos θ with respect to θ.
Accordingly, the microlens 115 collects the light emitted from the OLED in the vertical upward direction.

In FIG. 1A, the size and pitch of the microlens 115 are matched to the size and pitch of the organic EL layers 250R, 250G, and 250B, and thus one OLED, but are not limited thereto.
In any case, the size and pitch of the microlens 115 must be matched to the size and pitch of the pixel in the case of recent high-definition display, and is of the μm (micron) class.

The present invention is based on the fact that such micron-class precision machining has been put to practical use for the first time due to recent technological advances. For example, Non-Patent Document 3 includes a silicone resin as a material, When one kind of PDMS (Poly-Di-Methyl-Siloxane) is applied, the substrate is highly adaptable to warping, chemically inert, isotropic, homogeneous, transparent, and highly durable as an elastomer. It is described that a controllable surface state can be formed by treatment and subsequent chemical treatment.
Y Xia et al: Soft Lithography, Angew. Chem. Int. Ed. 1998, 37, pp550-575.

Therefore, when this PDMS material is used, a desired microlens array can be obtained with good releasability at low cost from, for example, embossing from a micron-class master made of silicon.
The state-of-the-art processing technology of silicon is 0.1 micron class, and the above micron class matrix can be obtained at low cost.

  The distance between the protruding end of the microlens 115 and the upper surface protective film 270 of the OLED is preferably as small as possible in order to increase the light collection efficiency. However, even if the substrate 200 or the cap 100 is warped, The value is set to such a value that a portion is not pressed against the protective film and deformed.

  FIG. 1B is a schematic cross-sectional view showing an organic EL device according to the present invention. The difference from the first embodiment is that the microlens array 110 is provided not on the inner surface of the cap 100 but on the outer surface. It is that you are.

  In this case, since the organic EL layer is sealed by the cap and separated from the microlens array, there is a risk that even if a slight amount of water, oxygen, or the like is attached to the microlens array, the organic EL layer may be damaged. Absent.

  Referring to FIG. 1C, which is a schematic cross-sectional view showing an organic EL device according to the present invention, the difference from the first and second embodiments is that the microlens array 110 is not on the inner surface or outer surface of the cap 100. The OLED transparent electrode film 260 is provided on the upper surface side of the OLED through a protective film 270.

  In this way, the light condensing by the microlens 115 can be most efficiently performed, and the microlens array 110 most effectively protects the OLED.

  Referring to FIG. 2 (A), it is a schematic cross-sectional view showing an organic EL device according to the present invention. The difference from the first to third embodiments is that a microlens 115 is attached to the inner surface of a cap 100 made of silicone resin. That is, the microlens 115 and the cap 100 are integrally molded from a silicone resin.

  Therefore, when the PDMS material, which is a silicone resin, is used in the same manner as in the first embodiment, a desired microlens array and a cap are integrated from a micron-type mother die made of silicon, for example, by embossing, for example, with good releasability. It can be obtained inexpensively.

  Since the silicone resin PDMS is transparent as described above, the OLED emits light to the outside, while it is chemically inactive, so it protects the internal OLED and adapts to the warp of the substrate, making it ideal as a cap. With typical performance.

Furthermore, generally, the dangling bonds of Si atoms on the surface of the silicone resin can be stably bonded to OH groups by, for example, oxygen plasma treatment.
When adhering / sealing the substrate 200 and the leg portion 105 of the cap 100, if the primer surface is preliminarily treated on the bonding surface (bonding portion 120) of the substrate 200, the OH group of the cap 100 is dehydrated. As a result, the Si atoms on the surface of the silicone resin are chemically bonded to the molecules of the bonding portion 120, and strong adhesion / sealing is obtained.

  Referring to FIG. 2B, the size / pitch of the microlens corresponds to the organic EL layers 250R, 250G, 250B, and thus the size / pitch of the OLED in Example 4 above, whereas In the embodiment, there is a one-to-two correspondence.

  Referring to FIG. 2C, the size / pitch of the microlens corresponds to the size / pitch of the OLED on a two-to-one basis.

In general, the smaller the microlens, the shorter the focal length is obtained. However, since aberration distortion increases, considering the size and pitch of the OLED, the distance between the OLED upper surface and the microlens and their variations, The size and pitch of the microlens must be determined so that a stable light collection rate can be obtained over the entire panel.
This naturally holds true for the above-described Examples 1, 2, and 3, and Example 7 below, which are other examples.

  Referring to FIG. 3, which is a schematic cross-sectional view showing an organic EL device according to the present invention, a transparent cap 100 made of glass, for example, having a microlens 115 on the inner surface, the entire upper surface of a substrate 200 on which an OLED is mounted. The gap between the two is filled with the silicone resin PDMS including the leg portion 105 of the cap 100 and the adhesive portion 120 of the substrate 200 to form the filling portion 130.

  In this way, PDMS effectively protects the OLED in a single process, and at the same time, the substrate 200 and the cap 100 can be effectively bonded by the bonding part 120. For example, PDMS can be performed at room temperature for 48 hours, Since it can be cured at a low temperature of about 4 hours at 65 ° C., it does not damage the organic EL layer.

  When adhering / sealing the substrate 200 and the leg portion 105 of the cap 100, if the primer surface is previously preliminarily treated with the primer, the silicone filled in the adhesion portion 120 The OH groups on the surface of the resin are removed by a dehydration reaction, and Si atoms on the surface of the silicone resin are chemically bonded to molecules on the adhesion surface of the substrate and cap, thereby obtaining strong adhesion and sealing.

  4, 5, 6, and 7 are schematic cross-sectional views showing the structures of the organic EL elements in Examples 8, 9, 10, and 11, and FIGS. 8, 10, and 12 are examples. Optical equivalent cross-sectional views of the organic EL elements in 8, 9, and 10, FIGS. 9, 11, and 13 are distribution diagrams of light emission amounts of the organic EL elements in Examples 8, 9, and 10, respectively.

FIG. 4 is a schematic cross-sectional view showing the structure of the organic EL element in Example 8.
The organic EL element body is formed on a metal substrate, for example, a magnesium substrate 201, covered with a transparent cap 100 made of, for example, glass, and legs (not shown) extending downward at the edge of the cap are substrates. It is sealed by being adhered to the corresponding edge portion of the film, and is blocked from the outside.

  The organic EL element body is composed of, for example, a plurality of organic EL light emitting diodes (OLEDs) corresponding to one panel and a corresponding pixel driving unit. For example, polysilicon is formed on an insulating film 210 formed on the upper surface of the substrate 201. A layer or amorphous silicon layer 220 is deposited in which the pixel drive unit is formed.

In principle, each pixel driving unit is a single TFT transistor, and includes a source 231, a gate insulating film 237, a drain 235, a source wiring 233, a gate wiring 239, and a drain wiring 310.
The source wiring 233 and the gate wiring 239 form a row and a column, respectively, and are driven by a row / column driving circuit provided at an edge of the pixel driving unit array, and connected to the gate wiring to which a selection potential is applied. The drain potential is equal to the pixel signal potential applied to each source wiring, and thus an arbitrary signal potential is sequentially applied to the drain wiring of each pixel driving unit.

The drain wiring 310 is connected to the drain 235 through an appropriate barrier metal layer if necessary.
Of the upper surface of the polysilicon (amorphous silicon) layer, a region between adjacent pixel driving units is covered with a silicon nitride oxide insulating film 225, and the drain wiring 310 is extended on the upper surface of the OLED. One transparent electrode film is formed.

Each OLED includes a first transparent electrode film 310, a common second transparent electrode film 320, and an organic EL layer 300 sandwiched between the two electrode films, and usually three adjacent organic EL layers 301, 300, and 302. Corresponds to the three primary colors R, G, and B.
A low work function alloy, for example, an Mg—Ag layer 322 is interposed between the second transparent electrode film and the organic EL layer 300 in order to increase electron injection efficiency.
The thickness of the Mg—Ag layer is thin so as not to impair the transparency, for example, about 10 nm.
Further, a protective film (not shown) is formed on the second transparent electrode film 320.

In this way, the organic EL element body is formed.
Here, the typical film pressure of each film and layer related to the light emitting part of the organic EL element is enumerated.
Substrate insulating film 210: 10 nm, polysilicon (amorphous silicon) layer 220 (including insulating film 225): 500 nm, first transparent electrode film 310: 100 nm, organic EL layer 300: 60 nm, Mg—Ag layer: 10 nm, second Transparent electrode film 320: 40 nm.

When a predetermined signal voltage that changes with time is applied to the row / column wiring of the pixel driving unit of the organic EL element body after the sealing with the cap is completed, each organic EL layer 300 changes corresponding to the signal voltage. One of the three primary color lights having a light amount is emitted.
The three primary color lights are respectively emitted from the upper side through the Mg-Ag film 322, the second transparent electrode film 320, the protective film, and the transparent cap 100, and each pixel has a desired color tone, and serves as a display device. Will serve the function.
The luminance of the organic EL element is determined by the light emission amount of the OLED when the signal voltage is maximum. Hereinafter, the “light emission amount” is limited to this case.

As described above, the light emission amount of the organic EL layer becomes maximum in the vertical direction in FIG. 1, becomes zero in the horizontal direction, and forms a cos θ distribution with respect to the angle θ measured with the upward direction as the base line.
Therefore, in the case of the present embodiment, light emission in the downward direction in FIG. 4, that is, in the range of 90 ° ≦ θ ≦ 180 °, is transmitted through the first transparent electrode film 310, the polysilicon (amorphous silicon) layer 220, and the insulating layer 210. Thus, the light reaches the boundary 205 of the base metal of the insulating layer 210 and the substrate 201, and light cannot be transmitted through the metal substrate 201 and is reflected.

That is, the boundary 205 functions as a light reflecting surface, and the reflected light travels upward as if it were light emission from the mirror image 305 (indicated by a two-dot chain line) of the organic EL layer 300. (Hereinafter, the light reflecting surface is also indicated by “205”.)
In FIG. 4, examples of direct light and reflected light are indicated by 11 and 16, 61 and 66, respectively.
Next, the distribution of the total intensity of the direct light and the reflected light is approximately estimated.

FIG. 8 is an optical equivalent cross-sectional view of the organic EL element in this example.
The dimension d and pitch D in the planar direction of the organic EL layer 300 and the distance s1 between the lower surface 102 of the cap are 0.1 mm to 1 mm, whereas the distance between the organic EL layer and the light reflecting surface 205 is the above-described distance. Even in the case of a typical film thickness, since it is at most 700 nm, that is, less than 1 μm (micron), it is considered that the organic EL layer, the light reflecting surface, and the mirror image 305 are in close contact and are all at a distance s1 from the lower surface of the cap.
In this figure, s1 = D = 2 × d.

  Therefore, the light emitted from the organic EL layer 300 is obtained by superimposing the direct light upward and the reflected light from below, and the left and right π / 2 (= 45 and 45), 11 and 12, 13 and 14, and 15 and 16 are representatively shown.

FIG. 9 is a distribution diagram of the light emission amount of the organic EL element in this example.
The light emission intensity Y (relative value) of the organic EL layer 300 is cos θ as shown by the broken line, where θ is the angle from the vertical upper side in the figure, but the negative Y portion corresponding to the lower light emission is reflected and the upper light emission The total emission intensity is 2 × cos θ (−π / 2 ≦ θ ≦ π / 2) as shown by the solid line, which can be doubled as compared with the conventional case without reflection.

FIG. 5 is a schematic cross-sectional view showing the structure of the organic EL element in Example 9.
Compared to Example 8 above, when an array of recesses is formed on the upper surface of the metal substrate 201 in advance in the figure and the insulating film 210 is formed by oxidizing the surface in the same manner, a light reflecting surface that functions as a concave mirror 205 is obtained.

After forming the transparent layer 215 on the metal substrate 201 and planarizing the upper surface, the layers after the polysilicon layer or the amorphous silicon layer 220 are formed in the same manner as in the eighth embodiment.
In the case of the active matrix drive type as in this embodiment, the process for forming the polysilicon layer or amorphous silicon layer 220 and the TFT transistor therein may require high temperatures. Apply low melting glass.
In the case of the passive matrix drive type, when the subsequent process does not require high temperature, the transparent layer 215 can be made of, for example, a silicone resin, especially PDMS (Poly-Di-Methyl-Siloxane).
PDMS is highly adaptable to substrate warpage, is chemically inert, isotropic, homogeneous, and transparent, and has high durability as an elastomer, and is controlled by plasma treatment and subsequent chemical treatment. Since a possible surface state can be formed, it can be in close contact with the first transparent electrode film and the like, and can absorb stress due to a difference in temperature coefficient.
Next, the distribution of the total light emission intensity in this example is estimated.

FIG. 10 is an optical equivalent cross-sectional view of an organic EL element in Example 9.
Direct upward light emission is indicated by light rays 11-16 as in Example 1 above.
On the other hand, light emitted downward is reflected by the concave mirror, but in this embodiment, the distance s2 between the light reflecting surface 205 forming the concave mirror array and the organic EL layer 300 is equal to the focal length f1 of the concave mirror. The reflected light becomes parallel for each point light source on the organic EL layer.
In general, since the refractive index of the transparent layer 215 is larger than 1, the transparent layer 215 functions as a convex lens for each of the downward emission and reflected light. Therefore, precisely, f1 is not the focal length of the concave mirror alone, but the concave mirror and This is the focal length of the composite system with two convex lenses by the transparent layer 215.
Strictly speaking, the light reflecting surface changes along the concave surface of the concave mirror (the arc-shaped broken line below the light reflecting surface 205 in the figure), but here it is represented by a plane for simplicity.
In this embodiment, the diameter of the concave mirror is equal to the pitch D of the organic EL layer.

  That is, among the light rays emitted downward from the left end, the center, and the right end of the organic EL layer in the figure, the light rays in the range of φ4 between 51 and 52, φ5 between 53 and 54, and φ6 between 55 and 56 are reflected. And parallel rays, 61 and 62, 63 and 64, and 65 and 66, respectively.

FIG. 11 is a distribution diagram of the light emission amount of the organic EL element in this example.
The intensity distribution of the upper light emission follows cos θ (−π / 2 ≦ θ ≦ π / 2) indicated by a broken line, but the lower light emission is in the range of φ4 to φ6, that is, about 0.1π ≦ θ ≦ about π / Part or all of the portion 4 is concentrated to 0 ≦ θ ≦ 0.1π in the reflected light.
As a result, as shown by the solid line, the total emission intensity is concentrated at about −0.1π to + 0.1π, and the peak value is about 2.8 at θ = 0, which is compared with the conventional case where there is no reflection. 3 times, which is further improved compared to about 2.0 in the case of Example 8 above.
In this way, the emission intensity / power consumption ratio can be improved when the organic EL display device is viewed from the front (θ to 0).

FIG. 6 is a schematic cross-sectional view showing the structure of the organic EL element in Example 10.
For example, as shown in FIG. 6, for example, a convex microlens 115 facing the organic EL layer is further provided on the lower surface 102 of the cap 100 as shown in FIG.
Upper emitted light rays 11 and 16 from the organic EL layer are refracted by the microlens to become external light rays 21 and 26.
On the other hand, the lower emission light beam is reflected by the light reflecting surface 205 to become reflected light beams 61 and 66, and refracted by the microlens to become external light beams 71 and 76.

As a material for the microlens array, for example, when silicone resin, especially PDMS (Poly-Di-Methyl-Siloxane), is applied, it has good adaptability to the warping of the cap, is chemically inert, isotropic, and is homogeneous. In addition to being transparent, it has high durability as an elastomer, so that stress due to a difference in temperature coefficient can be absorbed.
Next, the distribution of the total light emission intensity in this example is estimated.

FIG. 12 is an optical equivalent cross-sectional view of the organic EL element in Example 10.
(Strictly speaking, both surfaces or one surface of the microlens 115 changes with a predetermined curvature (the arcuate broken line in the drawing of the microlens 115), but here it is represented by a plane for simplicity.
Further, the distance s1 between the organic EL layer 300 and the microlens 115 is set equal to the focal length f2 of the microlens in this embodiment. )

  Accordingly, in the figure, the light beam emitted from the upper side from the left end, the center, and the right end of the organic EL layer and the light beam emitted downward and reflected by the light reflecting surface 205 are superimposed, and among these, between 11 and 12, φ1, 13 The light rays in the range φ2 between 14 and 14 and φ3 between 15 and 16 are reflected into parallel rays 21 and 22, 23 and 24, and 25 and 26, respectively.

FIG. 13 is a distribution diagram of the light emission amount of the organic EL element in this example.
In the case of this example, the upper and lower light emission are superimposed, and the range of φ1 to φ3 in the cos θ (−π / 2 ≦ θ ≦ π / 2) distribution, that is, about 0.1π ≦ θ ≦ about π / Part or all of the portion 4 is concentrated to 0 ≦ θ ≦ 0.1π in the light emitted to the outside.
As a result, as shown by the solid line, the total emission intensity is concentrated at about −0.1π to + 0.1π, and the peak value is about 3.6 at θ = 0, which is compared with the conventional case without reflection. 4 times increase, which is further improved compared with about 2.0 in the case of Example 8.

FIG. 7 is a schematic cross-sectional view showing the structure of the organic EL element in Example 11.
Compared to Example 8 above, when an array of recesses is formed on the upper surface of the metal substrate 201 in advance in the figure and the insulating film 210 is formed by oxidizing the surface in the same manner, a light reflecting surface that functions as a concave mirror 205 is obtained.
In addition, for example, a convex microlens 115 facing the organic EL layer is further provided on the lower surface 102 of the cap 100.

Upper emitted light rays 11 and 16 from the organic EL layer are refracted by the microlens 115 to become external light rays 21 and 26.
On the other hand, the lower emitted light beams 51 and 56 are reflected by the concave mirror-like light reflecting surface 205 to be reflected light beams 61 and 66, and are refracted by the microlens 115 to be external light beams 71 and 76.

  That is, the upper emission light beam is collected once by the microlens and the lower emission light beam is collected twice by the microlens and the concave mirror. Therefore, by appropriately selecting the position, size, and focal length of the microlens and the concave mirror, Furthermore, the light collection efficiency can be increased.

  14 is a schematic cross-sectional view of the organic EL elements according to Examples 12 to 15, FIG. 15 is a schematic view showing the molecular structure of the protective film of the organic EL layer element in Example 12, and FIG. 13 is a schematic diagram showing the molecular structure of the protective film of the organic EL layer element in FIG. 13, FIG. 17 is a molecular structure schematic diagram showing various aspects of the silicon-containing organic fluorine-based polymer according to Examples 12 to 15, and FIG. These are the flowcharts which show the formation procedure of the protective film of the organic EL layer in Example 15.

  14 is a schematic cross-sectional view of a top emission type organic EL device according to the present invention, in which a TFT layer 220 is formed on a substrate 200, and a plurality of TFT transistor circuits are formed in the TFT layer 220. 230 and row / column wirings (not shown) for selectively driving these are formed.

  The output of the TFT transistor circuit 230 is connected to the first electrode 240, the organic EL layer 250R, 250G, or 250B is formed on the first electrode 240, and the ITO transparent film made of the ITO transparent film is further formed thereon. The two electrodes 260 are formed, and an organic electroluminescent diode (hereinafter referred to as OLED) is constituted by the first electrode, the organic EL layer, and the second electrode.

  Normally, when a reference potential (ground potential) is applied to the second electrode and a selection voltage is applied to the selected row wiring, all TFT transistor circuits connected to the selected row wiring are activated and applied to the column wiring. Or a voltage corresponding thereto is applied to the first electrode, and the organic EL element emits light at a luminous intensity corresponding to the applied voltage. In the case of color display, an OLED including a set of red, green, and blue organic EL layers 250R, 250G, and 250B is selected.

Regarding the structure and operation of the organic EL element described so far, with respect to each of the row / column wiring and its driving circuit, TFT transistor circuit, first electrode, organic EL layer, and second electrode, more detailed description will be given. Omitted.
A protective film according to the present invention is formed on the second electrode, and includes a silica film 410 obtained by baking polysilazane and a silicon-containing organic fluorine polymer film 420.

Referring to FIG. 15, it is a schematic diagram showing the molecular structure of the protective film of the organic EL layer element in Example 12 of the present invention.
In the figure, the protective film comprises a silica film 410 obtained by baking polysilazane and a silicon-containing organic fluorine-based polymer film 420, and both are molecularly bonded with a one-dot chain line 401 as a boundary.

First, a silica film obtained by firing polysilazane will be described.
Polysilazane PHPS (PerHydroPolySilazane) is an inorganic polymer (polymer) that is soluble in an organic solvent with “—SiH ₂ —NH—” as the basic unit. Then, as a result of dehydrogenation and deammonia reaction, a dense high-purity silica (SiO ₂ ) film 410 is formed.
The bulk of silica consists of a polycrystal having “—Si—O—” as a basic unit, but Si atoms on the surface of the polycrystal are usually terminated with a hydroxyl group “—OH”.

Next, the silicon-containing organic fluorine-based polymer will be described.
Referring to FIG. 17, it is a schematic diagram of the molecular structure showing various aspects of the silicon-containing organofluorine polymer.

FIG. 17A is the most basic organic fluorine-based polymer, which is called a perfluoroalkane, in which all the hydrogen atoms of an acyclic saturated hydrocarbon (alkane) are substituted with fluorine atoms. .
Perfluoroalkane has a simple structure and is rich in water repellency and oil repellency, but it cannot ensure adhesion with an organic EL element to be protected.
Even if an unsaturated bond is introduced into perfluoroalkane (perfluoroalkene) or / and a side chain is introduced, it is not easy to achieve both water repellency, oil repellency and adhesion.

FIG. 17B is an example of a silicon-containing organic fluorine-based polymer, in which a silicon-containing group 439 is introduced and bonded to the end of the perfluoroalkane portion 432.
In this case, the silicon-containing group 439 includes a trimethyloxysilane group “—Si (OCH ₃ ) ₃ ”, and is bonded to the perfluoroalkane portion 432 via the hydrocarbon portion 434.

The hydrocarbon portion 434 was introduced as a silicon-containing group carrier in order to bond the silicon-containing group 439 to the perfluoroalkane portion 432, and the number of associated hydrogen atoms increases as the molecular weight of the hydrocarbon portion increases. A small molecular weight may be desirable because it may impair the water and oil repellency. In that case, the number of carbon atoms is 2 per silicon atom, and therefore a vinylsilane derivative is used as the carrier molecule for the silicon-containing group.
The perfluoroalkane 432 and the hydrocarbon portion 434 are collectively referred to as a main portion 430 of the silicon-containing organic fluoropolymer.

Referring again to FIG. 15, a film 420 made of a silicon-containing organofluorine polymer shown in FIG. 17B is formed on the upper surface of the silica film 410 obtained by baking the polysilazane.
The silicon-containing organic fluorine-based polymer reacts with the hydroxyl group on the surface of the silica on the silicon-containing group 439 side, the methyloxy group is removed from the silicon atom of the silicon-containing group 439, and the silicon atom on the surface of the silica 410 and the adjacent silicon-containing polymer Bonding via the silicon atom and oxygen atom of the group, the matrix 430 of the silicon-containing organofluorine polymer is bonded to the silica surface at the molecular level.

  Thus, particularly in the case of high-purity silica obtained by firing polysilazane, since most of its surface is silicon dioxide terminated with a hydroxyl group, the silicon-containing organic fluorine-based polymer coated and fired thereafter is The silicon-containing base side is integrated with silica and the same silicon dioxide bond as the silica itself, and strong adhesion at the molecular level can be ensured.

  In addition, the main part 430 of the silicon-containing organic fluorine-based polymer is composed of perfluoroalkanes, which occupy most of the main part 430, so that the main part 430 aligns upward and exhibits excellent water and oil repellency as a whole. According to the embodiment, the two-layer film composed of the silica film 410 and the silicon-containing organic fluorine-based polymer film 420 is an excellent protective film for the organic EL element.

Returning to FIG. 15, dirt 490 is generally difficult to adhere to the upper surface of the silicon-containing organic fluorine-based polymer aligned as described above due to water repellency and oil repellency, and even if temporarily attached, it can be easily eliminated.
However, even in high-purity silica, crystal irregularities exist due to crystal grain boundaries, crystal defects, etc., for example, as shown in the central part of FIG. If dirt 490 (aqueous or oily molecules) enters into the gap, the intrusion portion 490a may not be removed physically and chemically, and may cause deterioration of the OLED over time.

Referring to FIG. 16, in Example 13, a silicon-containing organic fluorine-based polymer main portion 440 having a flexible molecular structure is introduced.
Specifically, as shown in FIG. 17C, perfluoropolyoxetane is applied as the organic fluorine-based polymer to form a perfluorooxetane portion 442.
Perfluorooxetane is more commonly referred to as perfluoro (poly) ether, and a perfluoroalkane having only a straight chain consisting of several “—CF ₂ —” or three side chains (or three in the case of perfluoropolyoxetane) is an oxygen atom. Those bonded through O (ether bond).

  Since there are a plurality of ether bond portions due to oxygen atoms, the main portion 440 of the silicon-containing organic fluoropolymer is rich in flexibility, and there is a gap due to crystal irregularities on the surface of silica as shown in the center portion of FIG. Even so, since the main part of the silicon-containing organic fluorine-based polymer around the gap is bent, the gap is filled and the dirt molecules 490 are repelled, so that the water repellency and oil repellency of the dirt are further improved as compared with Example 12 above. Can be improved.

In Examples 12 and 13 described above, only typical and basic cases are used as the organic fluoropolymer part, hydrocarbon part, and silicon-containing group comprising perfluoroalkane, perfluoropolyoxetane (perfluoropolyether). showed that.
In the silicon-containing organofluorine polymer according to the present invention, introduction of side chains or / and unsaturated bonds in the organofluorine polymer part, change of the main chain carbon number in the hydrocarbon part, introduction of side chains, halogen of modified hydrogen Alternatively, various derivatives can be formed by substitution with hydrocarbons and substitution of methyloxy groups in silicon-containing groups with hydrogen, hydrocarbons, hydroxyl groups, or alkoxy groups, and their selective introduction and overall polymerization molecular weight. With this setting, it is possible to obtain a protective film having high antifouling characteristics that match the crystal irregularity characteristics of the corresponding silica surface and the characteristics of the fouling substance, and that is easy to apply and fire and has high productivity.

As an example, as shown in FIG. 17D, a hydrocarbon portion 454 composed of 4 carbon atoms is introduced instead of 2 carbon atoms in Example 13, and trimethyl is introduced into the first and third carbon atoms. Bonds loxysilane.
In this example, since the main part 450 of the silicon-containing organic fluorine-based polymer is bonded to the silica surface by two “—Si—O—” bonds, the adhesion strength at the molecular level is further improved. Since the orientation direction at the base of the main portion 450 is substantially parallel to the silica surface, crystal irregularities on the silica surface are more efficiently covered, and the antifouling property is further improved.

  Referring to FIG. 18, as Example 15, it is a flowchart illustrating a procedure for forming a protective film for an organic EL layer, which is common to Examples 12 to 14 described above.

In step S1, polysilazane (PHPS) is diluted with a cyclohexane solvent to obtain a polysilazane (PHPS) solution.
In order to enable humid drying at a relatively low temperature in the subsequent step S3, a predetermined metal catalyst is added.

  In step S2, a PHPS solution is applied on the ITO film of the organic EL element.

In step S3, humidification drying is performed for 1 hour at a temperature of 60 ° C. and a humidity of 90%.
Thereby, a dense and high-purity silica film is formed.

  In step S4, a silicon-containing organic fluorine-based polymer composed of a perfluorohydrocarbon portion, a hydrocarbon portion, and a silicon-containing group is diluted with perfluorohexane to obtain a solution of the silicon-containing organic fluorine-based polymer.

  In step S5, the silicon-containing organic fluoropolymer solution is applied onto the silica film.

In step S6, it is dried at room temperature for 1 hour. Alternatively, it is humidified and dried at a temperature of 60 ° C. and a humidity of 90% for 1 hour.
As a result, the silicon-containing organic fluorine-based polymer is bonded to the silicon of silica at the molecular level via the silicon-containing group.

  Through the above steps S2, S3, S5, and S6, the process can be performed statically at low temperature and normal pressure, and does not cause physical or chemical damage to the organic EL element. Therefore, moisture, oxygen, physical It is suitable for organic EL elements that are fragile with respect to impact.

Organic EL elements are attracting attention as elements for next-generation display systems that have low power consumption, high quality, low profile, and can also display curved surfaces. Therefore, it is necessary to further improve the effective luminous efficiency.
According to the present invention, an inexpensive and highly reliable peripheral structure that can increase the effective luminous efficiency even when the same organic EL layer is used is provided. Can contribute.

Claims (17)

  An organic EL light emitting diode (OLED) including a transparent electrode film, an organic EL layer, and a counter electrode layer, a substrate on which the OLED is mounted, and a portion facing the transparent electrode film are provided so as to cover the OLED. An organic EL element including a cap, comprising: a microlens array on an outer surface or an inner surface of the cap or on a surface side of the transparent electrode film.   2. The organic EL element according to claim 1, wherein the cap is made of a silicone resin, and the microlens is formed integrally with the cap.   The organic EL element according to claim 2, wherein a primer treatment is performed on a bonding portion of the substrate with the cap when the cap and the substrate are bonded.   An organic EL light emitting diode (OLED) including a transparent electrode film, an organic EL layer, and a counter electrode layer, a substrate on which the OLED is mounted, and a portion facing the transparent electrode film are provided so as to cover the OLED. In the organic EL element including a certain cap, a microlens array is provided integrally with the cap on an outer surface or an inner surface of the cap, and between the inner surface of the cap and the upper surface of the substrate including the upper surface of the OLED. An organic EL element, wherein the gap is filled with a silicone resin including the gap between the bonding surfaces of the cap and the substrate.   5. The organic EL element according to claim 4, wherein when the cap and the substrate are bonded, a primer treatment is performed on both the bonded portion of the substrate and the bonded portion of the cap.   6. The organic EL device according to claim 1, wherein the silicone resin is polydimethylsiloxane (Poly-Di-Methyl-Siloxane, PDMS). 7.   An organic EL device including an organic EL light emitting diode (OLED) including a first transparent electrode film, an organic EL layer, and a second transparent electrode film, and a substrate on which the OLED is mounted so that the first transparent electrode film is in contact therewith. In the EL element, an organic EL element comprising a light reflecting surface on a side of the substrate on which the OLED is mounted.   The organic EL element according to claim 7, wherein the substrate is a metal substrate having an insulating film formed on a surface thereof.   The organic EL element according to claim 7 or 8, wherein the light reflecting surface includes a concave mirror array including a plurality of concave mirrors.   Furthermore, the cap is provided so as to cover the OLED, and the portion facing the second transparent electrode film is transparent, on the outer surface or inner surface of the cap, or on the surface side of the second transparent electrode film, The organic EL element according to claim 7, further comprising a microlens array including a plurality of microlenses.   A silica film obtained by firing polysilazane (PHPS) and a silicon-containing organic fluorine polymer film laminated thereon, and the silicon-containing organic fluorine polymer of the silicon-containing organic fluorine polymer film is a perfluorohydrocarbon. A protective film for an organic EL device, comprising a part, a hydrocarbon part, and a silicon-containing group.   The protective film for an organic EL element according to claim 11, wherein the perfluorohydrocarbon part is composed of perfluoroalkane or perfluoroalkene having only a straight chain or a side chain.   The said perfluorohydrocarbon part consists of perfluoropolyether (perfluoropolyoctacene) which is only a linear chain or with a side chain, and contains only a saturated bond or an unsaturated bond. The protective film of the organic EL element.   The organic hydrocarbon according to claim 11, wherein the hydrocarbon part includes only a saturated bond, is only a straight chain, or has a side chain, and at least one of hydrogen atoms is substituted with the silicon-containing group. Protective film for EL element.   15. The protective film for an organic EL element according to claim 14, wherein one or more of the hydrogen atoms are further substituted with halogen.   12. The silicon-containing group according to claim 11, wherein one or more hydrogen atoms are substituted with an alkoxyl group or a halogen in a silane composed of one or more linear silicon. A protective film for organic EL elements. Diluting polysilazane (PHPS) with a cyclohexane solvent to obtain a polysilazane solution to which a predetermined metal catalyst is added;
Applying the polysilazane solution on the ITO film of the organic EL element;
Forming a silica film by humidifying and drying at a predetermined temperature of 20 ° C. to 100 ° C. and a predetermined humidity for a predetermined time;
Diluting a silicon-containing organofluorine polymer composed of a perfluorohydrocarbon part, a hydrocarbon part, and a silicon-containing group with perfluorohexane to obtain a solution of the silicon-containing organofluorine polymer;
Applying the silicon-containing organofluorine polymer solution onto the silica film;
Humidifying and drying at a predetermined temperature of 20 ° C. to 100 ° C. for a predetermined time to bond the silicon-containing organic fluorine-based polymer to the silicon atoms of silica at a molecular level;
The manufacturing method of the protective film of the organic EL element characterized by including.

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