JP2006088138A - Water capturing material, organic el light emitting device, and method for manufacturing them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL light emitting device, which can realize reduction in size, can be manufactured by a simple process, and can reduce the amount of dark frame, and a method for manufacturing the same. <P>SOLUTION: According to one embodiment of the present invention, the organic EL light emitting device includes a laminate comprising an organic EL layer 9 held between opposed electrodes and a water capturing material 22 disposed separately from the laminate. The water capturing material is provided so as to shield the laminate and the water capturing material 22 against the outside air and is composed mainly of molecular sieves or an alkaline earth metal oxide having an average particle diameter of not more than 15 μm and a purity of 99.9% and an inert oil. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water catching material, an organic electroluminescence (EL) light emitting device, and a method for producing them.

  In recent years, organic EL (Electro Luminescence) displays have attracted attention as FPD (Flat Panel Display). An organic EL display is a self-luminous display element, has a wider viewing angle than a liquid crystal display element, and can be thinned because a backlight is unnecessary. In addition, it has a high response speed and is expected as a next-generation display device because of the variety of luminescent properties of organic substances.

  The organic EL display includes an organic EL display panel in which a plurality of organic EL elements serving as pixels are arranged. In this organic EL display panel, for example, an organic EL layer is formed between intersections of anodes arranged in parallel stripes and cathodes arranged in parallel stripes so as to intersect the anodes. It has a sandwiched structure. A pixel as a light emitting element is formed at this one intersection. An organic EL display panel is configured by an infinite number of such pixels arranged in a matrix. This organic EL display panel is expected to be used as a display or a light source for a mobile phone. Much research has been conducted on the manufacturing method and various device structures, and detailed reports have been made (Non-Patent Document 1).

  However, the organic EL display panel has a problem that display characteristics such as light emission luminance and light emission uniformity deteriorate with time. This is because the light-emitting layer and the organic layer are deteriorated by moisture adsorbed on the surface of the component in the organic EL display panel, or by moisture or oxygen that has entered the organic EL display panel. As a result, the displayable area of the pixel area decreases with time. For this reason, a technique for suppressing a width (hereinafter referred to as “dark frame amount”) that cannot be displayed due to deterioration over time in spite of being a display area is important.

Therefore, in general, in an organic EL display panel, an organic EL element provided in the organic EL display panel is sealed so as to be shielded from outside air. Furthermore, a water catching material is disposed in the sealed organic EL element. As the water catching material, those of 1) powder type, 2) sheet type (for example, Patent Document 1, Patent Document 2), 3) paste type (for example, Patent Document 3) are known.
"Organic EL devices and the forefront of industrialization" NTT Publishing Co., Ltd., November 30, 1998 JP 2001-354780 A JP 2002-43055 A JP 2003-317934 A

  In order to achieve a longer lifetime of the organic EL display, it is necessary to develop a water catching material with better water catching capacity. It is also an important issue to simplify the manufacturing process of the organic EL display and to reduce the cost.

  By the way, the powder-type water catching material needs to have a structure that holds the powder firmly and does not scatter in order to isolate the powder-like water catching material from the light emitting part. For this reason, there is a problem that the structure becomes complicated and the size of the apparatus cannot be avoided. There is also a problem that workability is poor due to the powder form. Moreover, it is necessary to adjust the shape and magnitude | size of a sheet | seat type water catching material according to the magnitude | size of the organic EL element manufactured. Therefore, it is difficult to adapt to organic EL displays of various sizes and shapes, and there is a problem in versatility. On the other hand, the paste-type water catching material can be easily applied to the organic EL display regardless of the size or shape of the organic EL display simply by adjusting the coating amount to be applied from a nozzle or the like using a dispenser or the like. . Therefore, the versatility is high, the manufacturing process is simple, and the cost can be reduced.

  In addition, although the subject regarding the water catching material with which the organic EL display was equipped was demonstrated, it is not necessarily limited to an organic EL display, For example, also with respect to the light source device using an organic EL element provided with a water catching material. Similar challenges can arise.

  This invention is made | formed in view of the said background, and the 1st objective is high in versatility, and is providing the water catching material excellent in water catching, and its manufacturing method. A second object is to provide an organic EL light-emitting device that has a simple manufacturing process and that can suppress deterioration in light emission characteristics, and a method for manufacturing the same.

  The inventors of the present invention have made extensive studies to achieve the above object, and have completed the present invention.

  A first aspect of the present invention is a water catching material mainly composed of an inert oil and an adsorbent, wherein the adsorbent has a regular sieve or an average particle size of 15 μm or less, and a purity of 99.9%. A water catching material comprising at least one of the above alkaline earth metal oxides.

  The second aspect of the present invention is a water catching material containing at least one of CaO, BaO, and MgO as the alkaline earth metal oxide in the water catching material.

  The third aspect of the present invention is a water catching material that is a fluorine-based oil or a silicon-based oil.

  According to a fourth aspect of the present invention, in the water catching material, the inert oil is a fluorinated oil, and the content of the adsorbent is 25 to 33 wt%.

  According to a fifth aspect of the present invention, in the water catching material, the inert oil is a silicon-based oil, and the content of the adsorbent is 25 to 60 wt%.

A sixth aspect of the present invention is a water catching material using the water catching material having a viscosity of 1.5 × 10 ^{−3 to} 1.0 × 10 ⁻² Pa · s.

  According to a seventh aspect of the present invention, there is provided an organic EL light emitting device comprising: a laminate in which an organic light emitting layer is sandwiched between opposing electrodes; and a water catching material disposed apart from the laminate. And it arrange | positions so that this laminated body and this water catching material may be interrupted | blocked from external air, The water catching material in any one of the said 1st-6th aspect is provided as this water catching material. This is an organic EL light emitting device.

  An eighth aspect of the present invention is a method for manufacturing an organic EL light emitting device comprising: a laminated body in which an organic light emitting layer is sandwiched between opposing electrodes; and a water catching material arranged apart from the laminated body. In addition, as the water catching material, a material mainly containing an inert oil and molecular sieves or an alkaline earth metal oxide having an average particle size of 15 μm or less is prepared, and the laminate and the water catching material are prepared. This is a method for manufacturing an organic EL light-emitting device that is disposed so as to be shielded from outside air.

  A ninth aspect of the present invention is a method for producing a water catching material mainly composed of an inert oil and an adsorbent, wherein the adsorbent is a molecular sieve or an alkaline earth metal oxide having an average particle size of 15 μm or less. This is a method for producing a water catching material by preparing a product, heating and dehydrating the adsorbent, and then mixing the adsorbent and an inert oil.

  A tenth aspect of the present invention is a method for producing a water catching material, wherein the adsorbent is mixed with the inert oil in two or more times.

  Conventionally, detailed examination has not been made on the particle size of alkaline earth metal oxides. According to the first aspect of the present invention, a material having an average particle size smaller than the average particle size of alkaline earth metal oxides generally used conventionally and having a purity of 99.9% or more is used. By using it, water-capturing ability can be improved. Further, the use of molecular sieves as the adsorbent can effectively improve the water catching capacity. Since these water catchers are paste type, they are highly versatile.

  According to the third aspect of the present invention, since the fluorine-based oil or the silicon-based oil is used as the inert oil, the water capturing ability can be increased. The first reason why the water-capturing ability when using silicon-based oil is increased is that the water-permeable nature of silicon-based oil is higher than that of other inert oils, and the adsorbent present on the surface of the water-collecting material. Not only that, it is considered that the adsorbent present inside the water catching material can also exhibit the water catching ability. The second reason is considered to be because the water content of the silicon-based oil is higher than that of other inert oils.

  According to the fourth aspect of the present invention, it is possible to improve the coating performance while increasing the water catching capacity. By setting the content of the adsorbent to 25 to 33 wt%, it is possible to reliably apply a desired amount and a desired region with an application nozzle or the like, and to improve the yield in the manufacturing process.

  According to the fifth aspect of the present invention, the adsorbent can be kneaded without separation while increasing the water capturing capacity. By making the content of the adsorbent 60 wt% or less, it is possible to prevent the adsorbent from being separated. Moreover, the water-capturing property can be improved by setting the content to 25 wt% or more.

According to the sixth aspect of the present invention, it is possible to improve the coating performance while increasing the water catching capacity. By setting the viscosity of the water catching material to 1.5 × 10 ^{−3 to} 1.0 × 10 ⁻² Pa · s (that is, 1.5 to 10 cP), it is ensured that the desired amount is obtained by the application nozzle and the like. This can be applied to the region, and the yield in the manufacturing process can be improved.

  According to the seventh aspect of the present invention, since the paste-type material is mounted in the organic EL element as the water catching material, the apparatus can be miniaturized and the manufacturing process is simple. In addition, since the water catching performance is higher than that conventionally used, it is possible to suppress the deterioration of the light emission characteristics. As a result, the lifetime of the organic EL light emitting device can be increased.

  According to the 8th aspect of this invention, since the paste type thing is used as a water catching material, a manufacturing process is simple. Moreover, the manufacturing method of the organic electroluminescent light-emitting device which can suppress deterioration of a light emission characteristic can be provided by using the water catching material which water-absorbing improved compared with the past.

  According to the ninth aspect of the present invention, it is possible to provide a method for producing a water catching material with improved water catching than before.

  In this invention, there exists the outstanding effect that versatility is high and can provide the water catching material excellent in water catching, and its manufacturing method. In addition, the organic EL light emitting device can be reduced in size. Moreover, there is an excellent effect that an organic EL light emitting device that can be expected to have a long lifetime and a method for manufacturing the same can be provided.

  Embodiments to which the present invention can be applied will be described below. The following description is about the embodiment of the present invention, and the present invention is not limited to the following embodiment.

[Embodiment 1]
FIG. 1 is a schematic top view illustrating the configuration of the organic EL display panel according to the first embodiment. 2 is a cross-sectional view taken along the line AA ′ in FIG. As shown in FIG. 1, an organic EL display panel 100 according to Embodiment 1 includes an anode wiring 1, an anode auxiliary wiring 2, a cathode wiring 3, a cathode auxiliary wiring 4, an insulating film opening 5, an opening insulating film 6, and a cathode partition. 7, a contact hole 8 and an element substrate 10 are provided. As shown in FIG. 2, the organic EL display panel 100 according to the first embodiment includes an organic EL layer 9, a water capturing material 22, and a counter substrate 20. The anode wiring 1, the anode auxiliary wiring 2, the cathode wiring 3, the cathode auxiliary wiring 4, the insulating film opening 5, the opening insulating film 6, the cathode partition wall 7, the contact hole 8, etc. are collectively referred to as a laminate 12.

  As the element substrate 10, for example, an alkali-free glass substrate (for example, AN100 manufactured by Asahi Glass Co., Ltd.) or an alkali glass substrate (for example, AS manufactured by Asahi Glass Co., Ltd.) can be used. The thickness of the element substrate 10 is not particularly limited, but it is preferable to use a thickness of 0.7 to 1.1 mm, for example.

  As shown in FIG. 1, a plurality of anode wirings 1 are provided on the element substrate 10 and are arranged so as to be parallel to each other. As a material for the anode wiring 1, for example, ITO is preferably used.

  The anode auxiliary wiring 2 is disposed so as to be electrically connected to the anode wiring 1 at the end of the anode wiring 1 and to extend from the connecting portion with the anode wiring 1 toward the end of the element substrate 10. ing. Therefore, the same number of anode auxiliary wirings 2 as the anode wirings 1 are formed. Further, like the anode wiring 1, each is arranged in parallel. The anode auxiliary wiring 2 is connected to external wiring such as FPC (Flexible Printed Circuit) and TCP (Tape Career Package) via an anisotropic conductive film (hereinafter abbreviated as “ACF”) on the end side of the element substrate 10. Functions as a metal pad for connection. With this configuration, a current is supplied to the anode wiring 1 through the anode auxiliary wiring 2 from an external drive circuit.

  A plurality of cathode wirings 3 are provided as shown in FIG. 1 and are arranged so as to be parallel to each other and to be orthogonal to the anode wiring 1. The cathode wiring 3 usually uses Al or an Al alloy. In addition, alkali metals such as Li, Ag, Ca, Mg, Y, In, and alloys containing these can also be used. Alternatively, a transparent conductive film may be used. The thickness of the cathode wiring is about 50 to 300 nm.

  The cathode auxiliary wiring 4 is electrically connected to the cathode wiring 3 through the contact hole 8 at the end of the cathode wiring 3 and extends from the end of the cathode wiring 3 toward the end of the element substrate 10. It is arranged like this. Therefore, the same number of cathode auxiliary wires 5 as the cathode wires 3 are formed. Further, like the cathode wiring 3, they are arranged in parallel to each other. Similarly to the anode auxiliary wiring 2, the cathode auxiliary wiring 4 functions as a metal pad for connecting to an external wiring such as FPC or TCP on the end side. In addition, as a magnitude | size of the contact hole 8, it can be 200 micrometers x 200 micrometers, for example.

  The cathode auxiliary wiring 4 and the anode auxiliary wiring 2 can be formed of a metal film having a multilayer structure or a single layer structure. As an example, a multilayer structure can be formed by laminating a MoNb layer, an Al layer, and a MoNb layer in this order from the element substrate 10 side.

  The opening insulating film 6 is formed on the anode wiring 1, the anode auxiliary wiring 2, and the cathode auxiliary wiring 4 so as to cover a part thereof (see FIGS. 1 and 2). A pixel opening 5 is provided at a position where the anode wiring 1 and the cathode wiring 3 intersect. This pixel opening 5 corresponds to a display pixel region described later. For example, the film thickness of the opening insulating film 6 can be 0.7 μm, and the size of the pixel opening 5 can be 300 μm × 300 μm.

  The organic EL layer 9 is formed on the opening insulating film 6 as shown in FIG. 2 and has a structure sandwiched between the anode wiring 1 and the cathode wiring 3. For example, as shown in FIG. 3, the organic EL layer 9 includes a hole injection layer 91, a hole transport layer 92, a light emitting layer 93, an electron transport layer 94, and an electron injection layer 95. Of course, it may have a different layer structure. The thickness of the organic EL layer 9 is usually about 100 to 300 nm.

  The cathode partition 7 is disposed in parallel with the cathode wiring 3 as shown in FIG. The cathode partition 7 plays a role for spatially separating the plurality of cathode wirings 3 so that the wirings of the cathode wirings 3 do not conduct with each other. The cross-sectional shape of the cathode partition wall 7 is preferably an inversely tapered shape. The reverse tapered shape refers to a shape in which the cross-sectional width (the cross-sectional shape in the B direction in FIG. 1) of the cathode partition wall 7 increases in cross-sectional width (the B direction in FIG. 1) as the distance from the element substrate 10 increases. With this configuration, the side wall and the rising portion of the cathode partition wall 7 are shaded, and a plurality of cathode wirings 3 can be easily separated spatially in the manufacturing process of the cathode wiring 3 to be described later. As the size of the cathode partition 7, for example, one having a height of 3.4 μm and a width of 10 μm can be used.

  The element substrate 10 is bonded to the counter substrate 20 via a sealing material, and a space provided with the organic EL layer 9 and the like is sealed. The reason for sealing is to avoid the deterioration of the organic EL layer 9 due to moisture in the air. For example, a glass substrate having a thickness of 0.7 to 1.1 mm is used as the counter substrate 20. The same element substrate 10 may be used. On the counter substrate 20, a water catching material 22 is disposed in the sealed space with a gap from the organic EL layer 9, the cathode wiring 3, and the like described above. That is, it has an anode wiring 4, an organic EL layer 9, a cathode wiring 3, and the like, and a water catching material is disposed apart from the laminate 12 that becomes an organic EL element.

  The water catching material 22 is mainly composed of an adsorbent and an inert oil. The water catching material 22 may contain an additive as long as the water catching performance and the coating performance are not affected. Here, the inert oil is an oil that does not chemically react with other components contained in the adsorbent or the water capturing material, or other members present in the sealed space where the water capturing material 22 is disposed. Say.

The adsorbent in the water catching material 22 is mainly composed of molecular sieves or an alkaline earth metal oxide having an average particle size of 15 μm or less and a purity of 99.9% or more, and an inert oil. Use things.
Examples of the alkaline earth metal oxide include BaO, CaO, and MgO. The alkaline earth metal oxide contained in the water catching material 22 may be one type or a plurality of types.
As the inert oil, known oils can be used as long as they are not contrary to the gist of the present invention. Preferably, synthetic oil, more preferably fluorine-based oil, or silicon-based oil can be used.

The viscosity of the water catching material 22 is 1.5 × 10 ^{−3 to} 1.0 × 10 ⁻² Pa · s in consideration of applicability to the surface of a planar object from an application nozzle or the like installed in a dispenser or the like. (That is, 1.5 to 10 cP) is preferable. By setting the viscosity to 1.5 × 10 ⁻³ Pa · s or more, it is possible to effectively prevent the water catching material applied on the counter substrate 20 from flowing out. As a result, it is possible to prevent an adverse effect caused by the water capturing material adhering to the component on the element substrate side. Moreover, application | coating by an application nozzle etc. becomes easy by making a viscosity into 1.0 * 10 ^<-2 > Pa * s or less. Viscosity can be measured using, for example, a digital viscometer DV-II + (manufactured by Brookfield).

  In the case of using fluorinated oil as the inert oil, the content of the adsorbent in the water catching material 22 in consideration of applicability to the surface of the planar material from an application nozzle or the like installed in a dispenser or the like Is preferably in the range of 25 to 33 wt%. Examples of the fluorine-based oil include poly-trifluoro-chloroethylene and poly-fluoroalkylene glycol, but are not limited thereto, and known ones can be used.

  The water catching material 22 according to Embodiment 1 can be manufactured as follows, for example. First, an alkaline earth metal oxide having an average particle size of 15 μm or less is heated and dehydrated in a nitrogen atmosphere. For example, CaO powder is heated and dehydrated at 580 ° C. Thereafter, the alkaline earth metal oxide is mixed with the inert oil in a plurality of times. By dividing the alkaline earth metal oxide into a plurality of times, a paste-like water catching material with higher uniformity can be obtained.

  Next, a method for manufacturing the organic EL light emitting device according to Embodiment 1 will be described with reference to FIGS. In addition, the following manufacturing process is a typical example in the case of an organic EL display, and it cannot be overemphasized that another manufacturing method can be employ | adopted as long as it agree | coincides with the meaning of this invention. FIG. 4 is a flowchart showing manufacturing steps of the organic EL light emitting device according to the first embodiment. FIG. 5 is a cross-sectional view illustrating the configuration of the element substrate 10 and the counter substrate 20, and FIG. 6 is a top view of the element substrate 10 and the counter substrate 20. FIG. 7 is a plan view showing a cutting separation line, and FIG. 8 is a sectional view after the cutting separation.

  As step S <b> 1, an anode wiring material is formed on the element substrate 10. For example, ITO is used as the anode wiring material. The film formation is preferably performed by sputtering or vapor deposition from the viewpoint of forming the film with good uniformity on the entire surface of the substrate. For example, an ITO film having a thickness of 150 nm is formed by DC sputtering.

  Next, as step S2, the anode wiring material formed in step S1 is patterned by a photolithography process and an etching process. Thereby, the anode wiring 1 is formed. For the etching process, either a wet etching method or a dry etching method may be used. For example, a phenol novolac resin is used as the resist. The etching process employs a wet etching method, and uses a mixed aqueous solution of hydrochloric acid and nitric acid as a treatment liquid. As the stripping solution, for example, a monoethanolamine aqueous solution is used.

  Subsequently, as step S3, a material to be an auxiliary wiring is formed on the anode wiring. The film formation is preferably performed by sputtering or vapor deposition from the viewpoint of forming the film on the entire surface of the substrate with good uniformity. As the auxiliary wiring material, for example, a low-resistance metal material such as Al or an Al alloy can be used. In addition, from the viewpoint of improving adhesion to the base and preventing corrosion, a barrier layer such as TiN or Cr can be formed in the lower layer or upper layer of the Al film to make the auxiliary wiring a multilayer structure. This barrier layer can also be formed by sputtering or vapor deposition. For example, a Cr / Al / Cr multilayer structure having a total thickness of 450 nm is formed by DC sputtering.

  Next, as step S4, the auxiliary wiring material formed in step S3 is patterned by a photolithography process and an etching process. Thereby, the anode auxiliary wiring 2 and the cathode auxiliary wiring 4 are formed. For example, a wet etching method is employed, and an etching solution made of a mixed aqueous solution of phosphoric acid, acetic acid, and nitric acid is used as a processing solution. Of course, it is not limited to this, A well-known etching liquid can be used. It is also possible to pattern the auxiliary wiring material and the cathode wiring material in order after forming the anode material and the auxiliary wiring material in order.

  Thereafter, as step S5, an opening insulating film material is formed. As the opening insulating film material, for example, photosensitive polyimide can be used. For example, a polyimide film is formed by spin coating.

  Next, as step S6, the opening insulating film material is patterned. At the time of patterning, patterning is performed so that the pixel opening 5 and the contact hole 8 serving as a display area are opened. In the case of using photosensitive polyimide, a curing process is performed after the exposure process and the development process to obtain a pattern of the opening insulating film 6 having the insulating film opening 5 and the contact hole 8 as shown in FIGS. For example, the size of the pixel opening is 300 μm × 300 μm, and the size of the contact hole 8 is 200 μm × 200 μm.

  Subsequently, a cathode barrier rib material is deposited as step S7. As the cathode partition wall, a photosensitive novolac resin, a photosensitive acrylic resin, or the like can be used. As a film forming method, for example, a spin coating method can be employed.

  Thereafter, patterning of the cathode barrier rib material is performed as step S8. The cathode partition wall 7 is patterned in the gaps where the plurality of cathode wirings 3 are formed so as to be parallel to the cathode wirings 3 as shown in FIG. The cross-sectional shape of the cathode barrier 5 (the cross-sectional shape in the B direction in FIG. 1) is preferably a reverse taper structure. In order to obtain a reverse taper structure, it is preferable to use a negative photosensitive resin. This is because when a negative type photosensitive resin is used, in the exposure process, the lower the position of the cathode partition wall 5, the light reaction becomes insufficient, and the reverse taper structure can be easily formed.

  By providing the cathode barrier ribs 5 having a reverse taper structure, the cathode wires 3 can be spatially separated from each other when the cathode wires 3 described later are formed. This is because when the cathode wiring 3 is deposited, the deposition does not reach the shadowed portion when viewed from the deposition source. When a negative type photosensitive novolac resin is used, a curing process is performed after the exposure process and the development process to obtain a pattern of the cathode wiring 5. In addition, in order to perform surface modification of the ITO layer exposed by the insulating film opening 5 before step S9 described later, a step of irradiating oxygen plasma or ultraviolet light may be added.

  Subsequently, the organic EL layer 9 is mask-deposited as step S9. For example, the hole injection layer 91 is sequentially deposited so as to be 40 nm, the hole transport layer 92 is 10 nm, the light emitting layer 93 is 60 nm, the electron transport layer 94 is 30 nm, and the electron injection layer 95 is 0.5 nm.

  Further, in step S10, a cathode wiring material for forming the cathode wiring 3 is mask-deposited. Instead of mask vapor deposition, it may be formed by physical vapor deposition (PVD) such as sputtering or ion plating. For example, a cathode wiring 3 made of Al and having a thickness of 200 nm is formed.

  Through the above steps, a plurality of organic EL display panels are formed on the element substrate 10. Then, a plurality of organic EL display panels are obtained from one mother glass substrate by a cutting step (step S16) described later.

Next, a process for manufacturing a counter substrate for sealing the organic EL element will be described.
First, as step S <b> 11, a plurality of recessed water catching material accommodation portions 21 are provided on the counter substrate 20. As shown in FIG. 5, the water catching material container 21 is provided at a position facing the organic EL element provided on the element substrate 10. This is because a water catching material 22 for capturing moisture is provided at a position facing the organic EL display region 11. The concave shape of the water catching material accommodating portion 21 is formed by, for example, etching or sand blasting.

  Subsequently, as shown in FIG. 5, as shown in FIG. 5, a sealing seal 23 and a scattering prevention seal 24 are applied to the surface side of the counter substrate 20 where the water catching material accommodation portion 21 is provided as step S <b> 12. As shown in FIG. 6, the sealing seal 23 is applied to the outer frame portion surrounding the recess in which the water catching material accommodation portion 21 is provided. The sealing seal 23 plays a role of sealing the organic EL display region 11. The organic EL display region 11 is entirely surrounded by a sealing seal as shown in FIG. The cathode auxiliary wiring 4 and the anode auxiliary wiring 2 are extended to the outside of the sealing seal 23 so as to be connected to an external drive circuit described later. As shown in FIG. 6, the scattering prevention seal 24 is provided in the vicinity of the center of the gap between the organic EL display panels. The scattering prevention seal 24 plays a role of preventing the cut end material from scattering when the substrate for separating each organic EL display panel 30 described later is cut.

  Thereafter, as step S13, a paste-like water catching material 22 is applied. Application is performed by an application nozzle. The application amount is appropriately changed according to the size of the water catching material accommodation portion 21 so that an appropriate amount is applied.

  Each of the sealing materials can be applied using a dispenser or the like. As a material for the sealing seal 23, a photosensitive epoxy resin such as a cationic photopolymerization type epoxy resin can be suitably used. The same material can be used for the anti-scattering seal 24. Thereby, a manufacturing process can be simplified. The counter substrate 20 is manufactured as described above.

  Thereafter, in step S14, the element substrate 10 and the counter substrate 20 are bonded together (see FIG. 5). After aligning the element substrate 10 and the counter substrate 20, both substrates are pressurized, and each sealing material is irradiated with UV light. Thereby, the element substrate 10 and the counter substrate 20 are bonded together. Thereby, the organic EL display region 11 in which the organic EL layer 9 is formed is sealed.

  Finally, as step S15, the substrate on which the element substrate 10 and the counter substrate 20 are bonded is cut and separated according to the dotted lines 40 and 50 shown in FIG. A dotted line 40 in the figure indicates a position where the counter substrate 20 is cut, and a dotted line 50 in the figure indicates a position where the element substrate 10 is cut. The cut and separated substrate is configured as shown in FIG. As a result, each organic EL display panel 30 is divided.

  Thereafter, in step S16, a drive circuit and the like are mounted. ACF is attached to the ends of the cathode auxiliary wiring 4 and the anode auxiliary wiring 2 extending to the outside of the sealing seal 23, and connected to the TCP provided with the drive circuit. For example, the anisolum 7106U manufactured by Hitachi Chemical Co., Ltd. and the terminal portion of the auxiliary wiring are temporarily pressure bonded under the conditions of 80 ° C., 1.0 MPa, and pressure bonding time 5 s. Next, the TCP with the built-in drive circuit is subjected to main pressure bonding under the conditions of 170 ° C., 2.0 MPa, and pressure bonding time 20 s. Thereby, a drive circuit can be mounted. And the organic EL display panel 30 is attached to a housing | casing, and an organic EL display is completed.

  Embodiment 1 will be specifically described below with reference to examples, but the present invention is not limited thereto. Moreover, using the paste-like water catching material obtained in the following experimental examples (Examples 1 to 10 as examples and Examples A to C as comparative examples), the amount of dark frame, water catching, and coating are as follows. Sex was measured or evaluated.

(1) Applicability: The applicability of the paste-type water catching material produced in the following examples and comparative examples was evaluated. A case where a desired application amount could be applied to a desired application region by the application nozzle was indicated by ◯, and a case where a desired application amount could not be applied by the application nozzle to the desired application region was indicated by x.
(2) Measurement of the amount of dark frame: The paste type water catching material manufactured in the following examples and comparative examples was mounted on the organic EL display according to the above embodiment by the method described in the above embodiment. Thereafter, it was put into a high temperature and high humidity test tank of 80 ° C. × 90%. Then, the amount of dark frames after 300 hours (the width that cannot be displayed due to deterioration over time despite being originally a display area) is captured by a camera equipped with a lighted pixel in a microscope, and is displayed on a PC. Measurement was performed using length measurement software.

[Examples 1 to 10]
First, CaO as an alkaline earth metal oxide was heated and dehydrated in a nitrogen atmosphere at 580 ° C. Thereafter, 6 g of fluorinated oil, which is an inert oil, was placed in a mortar, and the alkaline earth metal oxide in the ratio shown in Table 1 below was placed in the mortar in three portions. At this time, the alkaline earth metal oxide was added and then kneaded so as to mix well each time. For example, in Example 4, 2 g of CaO2 having a purity of 99.9% was heated and dehydrated in a nitrogen atmosphere at 580 ° C. Subsequently, 6 g of fluorinated oil was put into a mortar, and 0.3 g of CaO dehydrated by heating was put into the mortar and kneaded with fluorine-type oil. Furthermore, 0.6 g of CaO dehydrated by heating was added to the mortar and kneaded. Finally, 1.1 g of CaO dehydrated by heating was added to the mortar and kneaded. The water trapping material thus manufactured was disposed in the organic EL display according to the manufacturing method according to the above embodiment. Then, the applicability was evaluated (see Table 1) and the dark frame amount was evaluated.

[Examples A to C]
Example A is the same as Example 4 except for the average particle size of the alkaline earth metal oxide (see Table 1). That is, in Example 4 above, an average particle diameter of 15 μm was used, but in Example A, an average particle diameter of 20 μm was used. Example B is a paste-type water catching material prepared as a conventional example. In the water catching material according to Example B, zeolite was kneaded with fluorine-based oil, and the weight concentration of zeolite was 20 wt%. Example C had the same conditions as Example 4 except that the alkaline earth metal oxide had a purity of 99.5%.

As shown in Table 1, in the samples of Examples 4 to 9 in which the weight concentration of the alkaline earth metal oxide was 25.0 wt% or more and 33.0 wt% or less, the result that the coating property was excellent was obtained. Since the applicability was good, it was possible to more effectively prevent the deterioration of the light emission characteristics.
In Example A, which is the same condition as Example 4 except that an alkaline earth metal oxide having an average particle size of 20 μm was used, a desired coating amount could not be applied to a desired coating region from the coating nozzle. . Even when MgO or the like is used as the alkaline earth metal oxide instead of CaO, or when some inert oils are used, the weight concentration of the alkaline earth metal oxide is 25.0 wt% or more. When the condition of 33.0 wt% or less was satisfied, it was confirmed that the coating property was good.

  For each condition in Examples 1 to 10, a water catching material of a comparative example in which only the average particle size was changed from 15 μm to 20 μm was prepared. And the dark frame amount of Examples 1-10 and each comparative example corresponding to each was compared. As a result, it was found that the amount of dark frame was significantly reduced in comparison with the case where an alkaline earth metal oxide having an average particle diameter of 20 μm was used. That is, it was found that by setting the average particle size to 15 μm, the water capturing performance can be significantly improved, and a long life can be achieved.

  Example 4 and Example C differ only in the purity of the alkaline earth metal oxide, and the other conditions are the same. Comparing these two examples, Example 4 in which the purity of the alkaline earth metal oxide is 99.9% as compared to Example C in which the purity of the alkaline earth metal oxide is 99.5% is Was decreasing more. That is, it was found that since the purity of Example 4 where the purity of the alkaline earth metal oxide was 99.9% was more excellent in water collection performance, a longer life could be achieved.

  FIG. 9 is a graph in which the organic EL display on which the samples of Example 4 and Example B are mounted is placed in a high-temperature and high-humidity environment, and the dark frame amount is plotted against time. The conditions are as described above. As a result, the dark frame amount after 300 hours of the high temperature and high humidity test was about 15 μm in Example 4 and about 29 μm in Example B. That is, in Example 4, since the water capturing property was improved, the deterioration of the light emission characteristics could be suppressed.

[Embodiment 2]
Next, an example different from the water catching material 22 provided in the organic EL display according to the first embodiment will be described. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

The organic EL display according to the second embodiment has the same basic configuration and manufacturing method as those of the first embodiment except that silicon-based oil is used as the inert oil. The viscosity of the water catching material 22A according to the second embodiment is 1.5 × 10 ^{−3 to} 1.0 × 10 ⁻² Pa · s (that is, 1.5 to 10 cP) for the same reason as in the first embodiment. It is preferable that

  Examples of silicone oils include dimethylsilicones such as methylpolysiloxane, octamethyltrisiloxane, and decamethyltetrasiloxane; cyclic dimethylsilicones such as decamethylcyclopentasiloxane, octamethylcyclotetrasiloxane, and polymethylsiloxane having a cyclic structure; There are methylphenyl silicons such as methylphenylpolysiloxane and polysiloxanes having a phenyl group in addition to a methyl group. Other silicone oils such as trimethylsiloxysilicic acid and methyl-modified polysiloxane, polyoxyethylene / methylpolysiloxane copolymer, poly (oxyethylene, oxypropylene) methylpolysiloxane copolymer, etc. There are silicon, methylhydrogen polysiloxane and the like.

  The adsorbent content in the water catching material 22A according to the second embodiment is preferably 25 to 60 wt%. This is because when the adsorbent mixing ratio is increased, separation from the silicon-based oil is a concern, and when the adsorbent mixing ratio is decreased, the water absorption may be decreased. Preferably, the mixing ratio is about 40 to 60 wt%, and in this case, thixotropy can be enhanced. More preferably, the mixing ratio is about 50 to 60 wt% and can be stably applied with a dispenser.

  The water catching material 22A according to the second embodiment can be manufactured as follows, for example. First, the adsorbent is heated and dehydrated in a nitrogen atmosphere. The silicon-based oil to be used is dehydrated as necessary. Thereafter, the adsorbent is mixed into the silicon-based oil in a plurality of times. By separating the adsorbent into a plurality of times, a paste-like water catching material with higher uniformity can be obtained.

  According to the water catching material 22A, since the silicon-based oil is used as the inert oil, the water catching ability is improved as compared with the case where other inert oil is used, and the deterioration of the light emission characteristics can be suppressed. The first reason that the water-capturing ability is improved is that the water permeability of silicon-based oil is higher than that of other inert oils. Therefore, not only the adsorbent present on the surface of the water-capturing material 22A, but also water trapping. It is considered that the adsorbent present inside the material 22A is also capable of exhibiting water capturing ability. The second reason is considered to be because the water content of the silicone oil is higher than that of other inert oils.

By the way, in an organic EL display having a paste-type water catching material, an inert oil that is one of the main components of the water catching material may be dyed in the course of time depending on the use environment conditions. FIG. 10A is a partial cross-sectional view of an organic EL display panel for explaining a passage route of intruding moisture when a conventional water catching material is used, and FIG. 10B is a water catching according to the second embodiment. It is a fragmentary sectional view of the organic electroluminescence display panel for demonstrating the passage route of the penetration | invasion water | moisture content at the time of using a material.
When the dyeing of the inert oil occurs from the water catching material 122, it first spreads on the counter substrate 120. Over time, the oil film of the inert oil propagates along the wall surface of the counter substrate 120 and spreads over the element substrate 110 (see FIG. 10A). Furthermore, when there is an inactive oil dyeing, an inactive oil pool may occur in the lower part of the organic EL display in the direction of gravity.

  Since the inert oil does not chemically react, even if it adheres to the laminate 112 including the light emitting layer, no particular problem occurs. However, when an inert oil film or an inert oil pool is generated, the amount of dark frame in the vicinity of the portion is larger than the dark frame amount in the vicinity of the portion where the inert oil film or inert oil pool is not generated. I found out. The reason is that moisture that has entered from the outside air in the sealing material for sealing 123 or through the interface between the sealing material for sealing 123 and the element substrate 110 is indicated by arrows W1 and W2 in FIG. It is considered that the element substrate 110 is trapped in the laminate 112 through the interface between the element substrate 110 and the inert oil film or the inert oil pool. In recent years, there is a tendency to reduce the ratio of non-pixel areas and increase the pixel area, but the dark frames with time tend to appear as the ratio of non-pixel areas decreases. This is because the distance between the side wall portion in the sealed space and the laminated body facing it becomes short, so that an inert oil film and an inert oil pool as shown in FIG. 10 are easily formed on the element substrate 10. It is.

  By using the water catching material 22A according to the second embodiment, even if the inert oil is oozed out depending on the use environment condition and an inert oil film or an inert pool is formed, it is located in the vicinity of the portion. It was confirmed that the amount of dark frames in the display area can be suppressed. As described above, this is considered to be because the water content and water molecule permeability of the silicon-based oil are higher than those of other inert oils. That is, the moisture that has entered from the outside air in the sealing material 23 for sealing or through the interface between the sealing material 23 for sealing and the element substrate 10 or the like is inert oil as indicated by arrows W3 and W4 in FIG. It is thought that the water is trapped in the water catching material 22A through the inside, or is contained in the inert oil film or the inert oil reservoir.

  By mounting the water catching material 22A according to Embodiment 2 on the organic EL display, it is possible to improve the water catching ability and suppress the deterioration of the light emission characteristics. Further, even if the inert oil is dyed depending on the use environment conditions, it is possible to suppress an increase in the dark frame of the display area located in the vicinity of the inert oil film or the inert oil reservoir.

  Embodiment 2 will be specifically described below with reference to examples, but the present invention is not limited thereto. The measurement of the dark frame amount is as described in the example according to the first embodiment.

First, molecular sieves as an adsorbent were dehydrated by heating in a nitrogen atmosphere at 450 ° C. After that, 7.0 g of silicone oil dimethylpolysiloxane (trade name: KF96, manufactured by Shin-Etsu Chemical Co., Ltd.) is put into a mortar, and 8.5 g of molecular sieves is put into the mortar in three portions and mixed together. Kneaded. The water trapping material thus manufactured was disposed in the organic EL display according to the manufacturing method according to the above embodiment. Then, the dark frame amount was evaluated. The evaluation method of the dark frame amount is the same as in the above embodiment.
The amount of dark frame after 300 hours of high temperature and high humidity test at 80 ° C. and 90% was about 14 μm. The dark frame amount of the example according to the present example was substantially the same as that of the example 4 according to the first embodiment, and could be significantly suppressed compared to the example B according to the first embodiment.

  In the first embodiment and the second embodiment, the example in which the invention is applied to an organic EL display has been described. However, the invention can be used for an apparatus to which a water capturing material can be applied. For example, the present invention can also be used for a light source device using an organic EL element. In this case, in the manufacturing method described above, instead of the organic EL display region 11, an organic EL light emitting region made of a planar organic EL element is formed on the element substrate 10. An organic EL light emitting region is surrounded by a sealing material 23 for sealing, and a planar light source device is manufactured by the same process. Thereby, a planar light source device having a uniform and high brightness can be obtained. The organic EL light emitting device includes devices utilizing light emission of organic EL elements such as an organic EL display and an organic EL light source device.

1 is a schematic top view of a configuration example of an organic EL display panel according to Embodiment 1. FIG. The fragmentary sectional view in the AA 'cut line of FIG. 1 is a cross-sectional view of an organic EL layer according to Embodiment 1. FIG. 5 is a flowchart showing a method for manufacturing the organic EL display according to the first embodiment. FIG. 3 is a cross-sectional view illustrating a configuration of an organic EL display according to the first embodiment. FIG. 2 is a plan view showing the configuration of the organic EL display according to the first embodiment. FIG. 3 is a plan view showing a cutting separation position of the organic EL display according to the first embodiment. FIG. 3 is a cross-sectional view showing a configuration after cutting and separation of the organic EL display according to Embodiment 1. The figure which shows the relationship between high temperature, high humidity test time, and the amount of dark frames. (A) The fragmentary sectional view of the organic electroluminescence display panel for demonstrating the passage route of the penetration | invasion water | moisture content at the time of using the conventional water catching material. (B) The fragmentary sectional view of the organic electroluminescence display panel for demonstrating the passage route of the penetration | invasion water | moisture content at the time of using the water catching material which concerns on Embodiment 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anode wiring 2 Anode auxiliary wiring 3 Cathode wiring 4 Cathode auxiliary wiring 5 Insulating film opening 6 Opening insulating film 7 Cathode partition wall 8 Contact hole 9 Organic EL layer 10 Element substrate 11 Display region 12 Laminated body 15 Inactive oil film 20 Counter substrate 21 Water catching material accommodating portion 22, 22A Water catching material 23 Sealing seal 24 Spattering preventing seal 30 Organic EL display panel 91 Hole injection layer 92 Hole transport layer 93 Light emitting layer 94 Electron transport layer 95 Electron injection layer 100 Organic EL display panel

Claims (10)

A water catching material mainly composed of inert oil and adsorbent,
The adsorbent is a water trapping material containing molecular sieves or at least one of an alkaline earth metal oxide having an average particle diameter of 15 μm or less and a purity of 99.9% or more.   The water catching material according to claim 1, wherein the alkaline earth metal oxide contains at least one of CaO, BaO, and MgO.   The water-absorbing material according to claim 1 or 2, wherein the inert oil is a fluorine-based oil or a silicon-based oil.   The water-absorbing material according to claim 1, 2, or 3, wherein the inert oil is a fluorinated oil, and the content of the adsorbent is 25 to 33 wt%.   The water-absorbing material according to claim 1, 2, or 3, wherein the inert oil is a silicon-based oil, and the content of the adsorbent is 25 to 60 wt%. Viscosity is 1.5 * 10 ^{< -3} > -1.0 * 10 ^<-2 > Pa * s, The water catching material of any one of Claims 1-5. A laminate in which an organic light emitting layer is sandwiched between opposing electrodes;
An organic EL light emitting device provided with a water catching material arranged apart from the laminate,
The laminated body and the water catching material are disposed so as to be shielded from outside air,
The organic EL light-emitting device using the water catching material of any one of Claims 1-6 as this water catching material. A laminate in which an organic light emitting layer is sandwiched between opposing electrodes;
A method of manufacturing an organic EL light emitting device provided with a water catching material arranged apart from the laminate,
As the water catching material, a material mainly composed of inert oil and molecular sieves or an alkaline earth metal oxide having an average particle size of 15 μm or less is prepared.
A method for producing an organic EL light emitting device, wherein the laminate and the water catching material are disposed so as to be shielded from outside air. A method for producing a water catching material mainly comprising an inert oil and an adsorbent,
Preparation of a water catching material in which molecular sieves or an alkaline earth metal oxide having an average particle size of 15 μm or less is prepared as the adsorbent, the adsorbent is heated and dehydrated, and then the adsorbent and inert oil are mixed. Method.   The method for producing a water catching material according to claim 9, wherein the adsorbent is mixed with the inert oil in two or more times.

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