JP2010021050A - Method of manufacturing organic electroluminescent device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of patterning an organic layer in which a patterning is carried out by reducing an effect to the organic layer after the organic layer is coated on all surfaces. <P>SOLUTION: A method of manufacturing an organic electroluminescent device includes the following steps: (A) one or more layers of the organic layer are formed on a substrate in which a transparent conductive film formed in a pattern shape is made a first electrode (anode layer + lead part), (B) a second electrode (positive electrode layer) is formed in pattern on the organic layer, (C) part of the organic layer on the first electrode which is determined beforehand is removed, and (D) a conductive layer is formed throughout the second electrode and the first electrode portion removed of the organic layer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a device manufacturing method using organic electroluminescence (hereinafter abbreviated as organic EL).

  In manufacturing an electronic device such as an organic EL, a functional layer is often formed on a substrate by applying a coating solution containing an organic solvent on the substrate. Examples of the application method include a spin coating method, an ink jet method, and an extrusion method (extrusion).

  In recent years, studies on using organic EL for illumination have been actively conducted. However, in the case of illumination applications, it is necessary to form a relatively large area uniformly. In general, when an EL element is manufactured, an inkjet method is often used because it needs to be applied in a partitioned area. The ink jet method can precisely control droplets and is suitable for producing a thin film with a small area, but the large area is inefficient in structure.

  As a method for uniformly coating a large area, a coating method using an extrusion die, so-called extrusion coating, is suitable.

  In the case of producing an organic EL element for illumination, it is preferable that the luminous efficiency is high in terms of luminance, life, power consumption, and heat generation. In that case, it is preferable to use a low-molecular phosphorescent material as an organic material option. .

  However, a coating solution in which a low molecular weight material is dissolved generally tends to be a solvent having a low viscosity of 0.5 to 3 mPa · s and a low boiling point as compared with a coating solution of a polymeric fluorescent material used for coating.

  Even if it is organic EL for illumination, pattern application is necessary because it is necessary to make an electrode take-out part, but a low-viscosity coating liquid is discharged onto the substrate by discharging a solution such as organic EL from a coating die of an extrusion coating device. In the case of application, even simple stripe application is difficult.

  For this reason, a method of removing a part of the organic layer once solid coating is performed once is disclosed (for example, refer to Patent Documents 1 to 3).

  In the case of removing these organic layers, conventionally, for the convenience of wiring the cathode to the transparent conductive film portion removed and exposed, it has been a method of removing and collecting the cathode before forming the cathode. However, this method has been desired to be improved because the part to be removed is not completely recovered or a part thereof causes redeposition and the like, and particularly when it adheres to the organic layer part, it causes element defects.

As a problem caused by the method of removing the organic layer with a solvent,
(A) The generated dust adheres to the organic layer, causing short circuits and dark spots. The thickness of the organic layer to be stacked is several tens of nm to several tens of nm. If the organic material is conductive, it may cause a short circuit to the cathode. Moreover, even if not, it becomes a non-light emitting part called a dark spot,
(B) When removing using a solvent, the organic solvent which volatilizes has an adverse effect on the organic layer (the cause is unknown at present).
JP 2004-152512 A JP 2007-280621 A JP-T-2007-515756

  An object of the present invention is to provide a method for patterning an organic layer by coating the entire surface of the organic layer and reducing the influence on the organic layer.

  The problems of the present invention can be solved by the configuration of the present invention.

1. (A) One or more organic layers are formed on the entire surface of the substrate using the transparent conductive film formed in a pattern as a first electrode (anode layer + lead portion),
(B) patterning a second electrode (cathode layer) on the organic layer,
(C) removing a part of the organic layer on the predetermined first electrode;
(D) forming a conductive layer over the second electrode and the first electrode portion from which the organic layer has been removed;
A manufacturing method of an organic electroluminescence element characterized by the above.

  2. 2. The method for producing an organic electroluminescent element according to 1 above, wherein the portion from which the organic layer has been removed is a lead portion of a first electrode provided on the substrate.

  3. 3. The method for producing an organic electroluminescent element according to 1 or 2, wherein the portion from which the organic layer has been removed is a lead portion of the first electrode and a non-light emitting portion of the anode layer provided on the substrate.

  4). The method for removing the organic layer is characterized in that a solvent capable of dissolving the organic layer is used, the solvent is applied to the removal portion, the organic layer is dissolved, and the solution is recovered to remove the organic layer. The manufacturing method of the organic electroluminescent element of any one.

  5. The method for removing an organic layer is characterized in that a solvent that dissolves the organic layer is used, a solvent is applied to the removal portion, and a wiping member is contacted to dissolve or swell and peel the organic layer. The manufacturing method of the organic electroluminescent element of any one.

  6). The method for removing the organic layer is characterized in that a solvent that dissolves the organic layer is used, a solvent is applied to the wiping member, the wiping member is brought into contact with the removal portion, and the organic layer is dissolved or swollen and removed. The manufacturing method of the organic electroluminescent element of any one of said 1-3 to do.

  7). 4. The method for producing an organic electroluminescent element according to any one of 1 to 3, wherein the method for removing the organic layer physically peels the organic layer.

  8). 8. The method for producing an organic electroluminescent element according to 7, wherein the physically peeling method is a laser ablation method.

  In the present invention, the organic layer is applied over the entire surface, the cathode is patterned and formed, the organic layer in a predetermined range is removed, and then necessary internal wiring (film formation) is performed.

  As a result, the organic layer is protected by the metal (aluminum or the like, the film thickness is 100 nm or more and the organic layer film thickness is several tens to several tens of nm), and even if dust is generated, It is difficult to cause a short circuit or a dark spot, and when it is removed using a solvent, it is protected from the volatile organic solvent atmosphere.

  Furthermore, since the organic layer is covered with metal at an early stage, the organic layer in the light emitting area is protected from oxygen and moisture.

  According to the present invention, the organic layer is protected by a metal (aluminum or the like, the film thickness is 100 nm or more, the film thickness of the organic layer is several tens to several tens of nanometers), which is unlikely to cause a short circuit or a dark spot. Since the organic layer is covered with a metal, the organic layer in the light emitting area can be protected from oxygen, moisture, and solvent atmosphere.

  The present invention provides a method for wiping and removing at least a part of an organic layer from an organic layer uniformly formed on a substrate to reduce adverse effects when the organic layer is patterned on the substrate. By this method, each organic functional layer (organic layer) of various types of organic EL elements can be patterned, and an organic EL element (OLED) having such an organic functional layer can be provided.

  Such an organic EL element includes an electrode and an organic functional layer disposed on the electrode. The organic functional layer is made of an organic material, has a first pattern disposed on a surface adjacent to the electrode, and has a substantially uniform thickness.

  This invention is providing the influence reduction method in the removal patterning in the organic functional layer for organic EL elements. Such an organic functional layer is made of an organic EL material.

  After forming a continuous sheet of organic functional material and forming a cathode in the light emitting portion, a part of the organic functional material is removed, and then a conductive layer is patterned over the cathode and the extraction electrode.

  Hereinafter, the present invention will be described in more detail.

  The layer structure of the organic EL element of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of a general organic EL element.

  In FIG. 1, an organic layer 4 including a light emitting layer is formed on a transparent conductive film (anode layer 2 + lead portion 3) patterned on a substrate 1, a cathode layer 5 is formed thereon, and the cathode layer 5 is It is connected to the lead part 3. When direct current is supplied to the anode layer 2 and the lead portion 3, light is emitted from the substrate 1 in the direction of the arrow.

  FIG. 2 shows formation of the organic EL device shown in FIG. 1 by a conventional process.

  In FIG. 2A, an anode layer 2 and a lead portion 3 made of a transparent conductive film are patterned on a substrate 1. In FIG.2 (b), the organic layer 4 is formed in the whole surface on it. In FIG. 2C, a part of the organic layer is removed and the organic layer is patterned. At that time, the generated dust 10 adheres to the surface of the organic layer. In FIG. 2 (d), the cathode layer 5 is formed by patterning on the organic layer 4. The dust 10 adhering to the organic layer surface may cause a short circuit between the cathode and the anode, or may become a dark spot.

  FIG. 3 shows a process for forming an organic EL device according to the present invention.

  In FIG. 3A, an anode layer 2 and a lead portion 3 made of a transparent conductive film are patterned on a substrate 1. In FIG.3 (b), the organic layer 4 is formed in the whole surface on it. In FIG. 2C, the cathode layer 5 is formed by patterning on the organic layer 4. In FIG. 3D, a part of the organic layer is removed and the organic layer is patterned. At that time, the generated dust 10 adheres to the surface of the cathode layer 5. In FIG. 3E, the conductive layer 6 is formed across the cathode layer 5 and the lead portion 3. The dust 10 adhering to the surface of the cathode layer does not cause a short circuit between the organic layer 4 and the anode layer 2 and is less likely to be a dark spot. Further, the organic layer 4 is protected by the formed cathode layer 5.

  FIG. 4 is a plan view showing the formation process of the present invention. 4A shows the first electrode (the anode layer 12 and the lead portion 13) formed on the surface of the flexible base 11 and the alignment mark 17 indicating the cutting position, and FIG. The state in which the organic layer 14 is formed on the entire surface is shown. In FIG. 4C, the second electrode (cathode layer 5) is formed by patterning thereon. FIG. 4D shows a state in which a part of the organic layer is removed and the extraction electrode 12a (a part of the anode layer) and the lead part 13 are exposed. In FIG. 4E, an organic EL element is formed by forming a conductive layer 16 connecting the cathode layer 15 and the lead portion 13.

  The organic EL elements formed on the continuous flexible substrate are separated based on the alignment mark 17 to form one element (shown by a broken line).

  Hereinafter, materials used for forming the EL element of the present invention will be described.

"substrate"
The substrate that can be used in the organic EL device of the present invention is not particularly limited in the type of glass, plastic, and the like, and may be transparent or opaque. When light is extracted from the support substrate side, the substrate is preferably transparent. Examples of the transparent substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable substrate is a resin film capable of giving flexibility to the organic EL element.

  Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate (TAC) and cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones Cycloolefin resins such as polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Can be mentioned.

  Examples of the opaque support substrate include metal plates such as aluminum and stainless steel, films, opaque resin substrates, and ceramic substrates.

<< Anode layer and lead part >>
Examples of the first electrode (anode layer and lead portion) used in the organic EL device of the present invention include a metal such as Au, and a conductive transparent material such as CuI, indium tin oxide (ITO), SnO ₂ , and ZnO. Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used.

  For the anode layer and the lead portion, a thin film may be formed on the substrate by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method. Alternatively, the electrode material may be vapor deposited. Alternatively, a pattern may be formed through a mask having a desired shape during sputtering. Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a coating system, can also be used.

  In the case of taking out light emission from this anode, it is desirable that the transmittance is larger than 10%, and the film thickness is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm, although it depends on the material.

《Organic layer》
The organic layer in the organic EL device of the present invention is an organic layer including a light emitting layer sandwiched between the above-described anode layer and a cathode layer described later, and may be a single layer or a multilayer structure. At least a light emitting layer is included.

  Examples of the organic layer include a light emitting layer, a hole transport layer, a hole blocking layer, an electron transport layer, a cathode buffer layer, and an intermediate layer. In the present invention, these are referred to as an organic layer.

  Each layer contains each functional material, and a coating liquid is formed with the functional material, a binder, and a solvent. When the functional material is a polymer compound and has a film-forming property, the coating liquid is made of a material excluding the binder. Is applied to the surface of the substrate having the patterned anode layer and the lead portion to form an organic layer.

  The formed organic layer is basically an entire surface coating that is not patterned.

  As an organic layer coating method, a spin coating method, a roll coating method, a curtain coating method, a slide coating method, an extrusion coating method, a wire bar coating method, or the like can be used.

《Cathode layer》
Next, a patterned cathode layer is formed on the aforementioned organic layer.

As the cathode layer, a material having a small work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃₎ mixture, indium, a lithium / aluminum mixture, and rare earth metals. The cathode layer can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 nm to 200 nm.

  As a patterning method, patterning may be performed by a method using a mask at the time of vapor deposition or sputtering, or by a lithographic method after forming a thin film.

<< Pattern removal method for organic layer in specified position >>
As an example of a precise and rapid patterning method of the organic layer, a method of removing a continuously formed organic layer in a pattern is used.

  For example, a method in which the organic layer is dissolved or swollen with a solvent and sucked and removed, or a method of wiping off can be used.

  In addition, there is a method of removing a part from an organic layer uniformly provided on a flexible substrate using a soft head or a wiping head such as a tape-like member that is “moistened” with a solvent. Preferably used. That is, the coating material is removed by tangential wiping using a wiping head.

  FIG. 5 is a schematic diagram showing an example of a wiping device that is preferably used in the present invention and that continuously removes a part of an organic layer from a continuous sheet on which an organic layer has been formed by wiping. is there.

  Fig.5 (a) is a side view of a wiping apparatus, FIG.5 (b) is the front view seen from the conveyance direction of the apparatus. The organic layer 14 is continuously formed on the entire surface of the first electrode (anode layer 12 + lead portion 13) pattern formed on the strip-shaped flexible substrate 11 formed in FIG. Further, the belt-shaped intermediate base material 30 on which the second electrode (cathode layer 15) is further formed is conveyed onto the pressing roll 31 of the wiping device.

  The wiping device has a wiping unit 22. The wiping unit 22 includes a feeding roll 36 for feeding the tape-like member 35 and a winding roll 37 for winding. Between the feed roll 36 and the take-up roll 37, a solvent supply means for supplying a solvent impregnating the tape-like member 35 is provided. This solvent supply means has a solvent holding tank 38 and a supply pipe 39 for guiding the solvent from there to the tape member 35. A pressing roll 41 for pressing the tape-like member 35 against the organic layer 14 is provided between the solvent supply pipe 39 and the take-up roll 37. The pressing roll 41 is connected to a cylinder 42, and can press the tape-like member 35 against the organic layer 14 on the strip-like flexible substrate with a desired pressure. The wiping unit 22 is supported by position adjusting means (not shown) that allows the wiping unit 22 to move in the width direction of the flexible substrate.

  FIG.5 (b) is the schematic front view seen from the conveyance direction which shows the state which makes this wiping unit contact the flexible base material which drive | works continuously, and wipes off.

  In FIG. 5C, an organic layer 14 is formed on the entire surface of the first electrode (the anode layer 12 and the lead portion 13) as shown in FIG. The second electrode (cathode layer 15) is formed, the tape-like member 35 is pressed against the intermediate substrate 30 to be conveyed, a part of the organic layer is continuously wiped in a strip shape, and this is removed and removed. As shown in FIG. 4C, the patterning is schematically shown.

  The tape-like member 35 is preferably selected from porous, solvent resistant, and fibrous woven fabrics and nonwoven fabrics having a width of 1 to 5 mm, depending on the pattern. Here, the tape-shaped member 35 has a width of 2 mm. Cotton cloth tape is used. The width of the tape-like member is preferably in the range of 100% to 80% of the wipe width, and particularly preferably in the range of 95% to 80% of the wipe width. This is because the organic layer adjacent to the tape-like member is wiped off by the wettability of the solvent with respect to the base material or the penetration of the organic solvent into the organic layer.

As the organic solvent, for example, a nonpolar solvent such as toluene or xylene is used to remove the light emitting layer material or the like. The pressing force of the tape-shaped member 35 against the organic layer is preferably in the range of 9.81 × 10 ³ Pa to 4.91 × 10 ⁵ Pa. Then, in order to continuously form a current extraction region in FIG. 4, that is, a part of the anode layer 12 and the lead portion 13 with the width of 2 mm, for example, along the conveying direction of the flexible base material, the pressing roller 21 A part of the organic layer is wiped off at a speed of 5 cm per second. The speed for wiping is preferably in the range of 1 to 50 cm / second, which is a relative speed and may be in the transport direction or the reverse direction.

  When it is too fast, the organic layer material is not sufficiently absorbed by the tape-shaped member, and the amount of wiping is increased. If it is too slow, the penetration of the solvent in the lateral direction into the organic layer disturbs the edge of wiping, resulting in poor patterning accuracy.

Thereby, the surface which consists of 1st electrode layer ITO can be continuously exposed in an external electrode connection area | region. As described above, the pressing force of the pressing roller 41 is preferably in the range of 9.81 × 10 ³ Pa to 4.91 × 10 ⁵ Pa. This is because when the pressing force is 9.81 × 10 ³ Pa or less, wiping of the organic layer tends to be insufficient, and conversely, when the pressing force is 4.91 × 10 ⁵ Pa or more, the electrode layer is damaged and a short circuit occurs. This is because it becomes easier.

  Then, an organic EL panel is formed by cutting each organic EL element formed on the flexible substrate. The formed organic EL panel can be further soldered to each of the current extraction regions (extraction electrodes 12a and lead portions 13) via external electrodes and connection regions to obtain an organic EL element.

  The wiping device by wiping is not limited to the above example, and instead of using a tape-like member, a blade made of a porous (for example, sponge-like) material having solvent absorption and elasticity is used as a base material. A method of wiping by pressing and rubbing may be used.

  For example, FIG. 6 shows an example of another type of wiping head.

  In this example, an example of a wiping head in which the organic layer 214 formed on the flexible substrate 211 is scraped off and the first electrode (the anode layer 212, the lead portion 213) is patterned is shown.

  The wiping head 230 is made of a solvent-resistant material made of a material such as sponge, elastomer, thermoplastic resin, fiber mat, porous material, polyurethane rubber, synthetic rubber, natural rubber, silicone, or a combination thereof. One form thereof, for example, a material such as solvent-resistant porous urethane rubber is formed. In the wiping head, for example, a part of the film is brought into contact with the tangential direction, and a part of the organic layer 214 is rubbed off.

  The prism 280 has a predetermined structure or geometric shape. In this embodiment, as a predetermined structure, the prism 280 has a trapezoidal cross-sectional shape. This shape may have a geometrical cross-sectional shape such as a pointed cross-sectional shape, a square cross-sectional shape, a rounded cross-sectional shape at the tip, etc. You may design together. The prism 280 has a predetermined thickness and has an elastic tip. Therefore, when wiping, the prism 280 can be bent and rubbed as a blade to wipe the organic layer.

  The wiping head 230 applies a force concentrated on the wiping portion prism 280 by the above-described pressing, and removes the organic layer by rubbing the wiping portion with the wiping head to pattern the film. (The solvent supply means is omitted). The film surface is moistened or pre-moistened with a liquid phase solvent. It is preferable that the solvent supply is performed prior to wiping by the wiping head and is performed immediately before wiping. In addition, the film surface may be previously moistened.

<< Connection between cathode layer and lead part >>
Next, conductive layer patterning is performed to connect the second electrode on the organic layer and the lead portion of the first electrode at the wiped portion.

  The conductive layer can be prepared by forming a thin film of an electrode material such as aluminum by a method such as vapor deposition or sputtering, and is selected in the range of 50 nm to 200 nm.

  As a patterning method, a method using a mask during vapor deposition or sputtering is preferable. Moreover, the method of apply | coating a conductive paste pattern by an inkjet system, or bonding a conductive film may be used.

  6C, a plurality of rows of first electrode anode layers 212 are formed, a plurality of rows of second electrodes (cathode layer 215) are formed thereon, and a part of the organic layer 214 is formed. When the lead electrode 213a of the anode layer 212 and the lead part 213 are exposed by scraping, the organic EL element is connected in series by connecting the cathode layer 215 and the lead electrode 212a of the anode layer 212 adjacent to each other by the conductive layer 216. A light emitting element connected to the substrate can be formed.

  Hereinafter, although an example is given and the concrete effect of the present invention is shown, the mode of the present invention is not limited to this.

<Preparation of organic EL panel 1>
Hereinafter, the production of the organic EL panel 1 will be described with reference to FIG.

[Formation of first electrode] (see FIG. 7A)
A polyethylene terephthalate film (Teijin-DuPont film, hereinafter abbreviated as PET) having a thickness of 100 μm, a width of 200 mm, and a length of 500 m was prepared. The strip-shaped flexible base material 311 is provided with an alignment mark (not shown) in advance to indicate the position where the first electrode (the anode layer 312 and the lead portion 313) is to be formed, and 5 × 10 ⁻¹ Pa. A 120 nm thick ITO (Indium Tin Oxide) film was deposited by sputtering under vacuum environment conditions, and a 10 mm × 10 mm first electrode (anode layer 312) having a lead 313 at the right end was fixed. It was continuously formed and wound in 12 rows at intervals.

[Formation of organic layer] (see FIG. 7B)
(First hole transport layer formation)
A solution obtained by diluting polyethylene dioxythiophene / polystyrene sulfonate (PEDOT / PSS, Baytron P AI 4083 manufactured by Bayer) with pure water at 65% and methanol at 5% is used as a first hole transport layer forming coating solution. The entire surface (excluding 10 mm at both ends) was applied using an extrusion coater so that the thickness after drying was 30 nm. After coating, drying and heat treatment were performed to form a first hole transport layer.

Coating conditions The coating conditions for the first hole transport layer forming coating solution are as follows: the temperature is 25 ° C., the dew point temperature is −20 ° C. or less in an N ₂ gas environment at atmospheric pressure, and the cleanliness class is 5 or less (JIS B 9920). I went there.

  After coating the first hole transport layer, the substrate was dried and wound up once. The solvent was supplied at a rate of 10 ml / min and a temperature of 10 ° C.

  Next, as described below, the organic layer 314 was formed by repeating coating, drying, and winding of the second hole transport layer, the light emitting layer, and the electron transport layer in order using an extrusion coating machine. The conveyance speed was 3 m / min.

(Second hole transport layer)
Under a nitrogen atmosphere, a solution of 50 mg of the hole transport material 1 (below) dissolved in 10 ml of toluene was formed into a film by the extrusion coating method. After drying, ultraviolet light was irradiated for 180 seconds in a nitrogen atmosphere to carry out photopolymerization and crosslinking to form a second hole transport layer having a thickness of about 20 nm.

(Light emitting layer)
A toluene solution containing 1% by mass and 0.1% by mass of PVK and dopant 4 was formed on the second hole transport layer by an extrusion coating method. It dried at 120 degreeC and was set as the light emitting layer with a film thickness of about 50 nm.

(Electron transport layer)
A 1-butanol solution containing 0.5% by mass of the electron transport material 1 was similarly formed on the light emitting layer by an extrusion coating method. It dried at 60 degreeC and was set as the electron carrying layer with a film thickness of about 15 nm.

  The material used for each layer of the organic layer is shown below.

Similarly, the coating conditions were as follows: the temperature was 25 ° C., the N ₂ gas environment having a dew point temperature of −20 ° C. or lower, the atmospheric pressure, and the cleanliness class 5 or lower (JIS B 9920).

[Formation of cathode buffer layer (electron injection layer)]
According to the position of the patterned anode, the light-emitting portion on the electron transport layer was deposited by mask pattern vapor deposition using LiF under a vacuum environment condition of 5 × 10 ⁻⁴ Pa with a vapor deposition apparatus, and the thickness was 0.5 nm. The cathode buffer layer (electron injection layer) was laminated.

[Formation of Second Electrode] (See FIG. 7C)
Subsequently, similarly aluminum mask pattern formed by a vapor deposition method using at 5 × 10 -4 ^Pa vacuum of fit emission portion on the cathode buffer layer (electron injection layer), an aluminum layer having a thickness of 100nm A second electrode (cathode layer 315) was laminated.

(Patterning of the organic layer: wiping step) (see FIGS. 7D and 7E)
The wound base material (PET) is supplied, positioning is performed using a microwave sensor using the first electrode pattern formed on the PET as a positioning mark, and the top of the extraction electrode portion of the first electrode is By using the wiping device 322, o-xylene, which is a solvent having a high affinity for the second hole transport layer and the light emitting layer, and 1-butanol, which is a good solvent for the electron transport layer, are mixed at a mixing ratio of 2: 1. The mixed solvent was supplied and rubbed and removed continuously by rubbing so that the relative speed of the pressing roll (tape-like member) with the base material was 5 cm / second. The pressing force of the wiping head was 1.96 × 10 ⁵ Pa. The total supply amount of the solvent was 20 ml / min.

  Thereafter, methyl ethyl ketone, which is a good solvent for swelling the hole transport layer, was supplied and similarly removed.

  A microwave irradiator used for positioning was a μ-reactor manufactured by Shikoku Keiki Kogyo Co., Ltd.

  As a result, the organic layer was removed and patterned by swelling or dissolution. The same removal operation was repeated to perform the patterning shown in FIG. After patterning, it was dried with a drying apparatus and temporarily wound up and stored.

(Formation of conductive layer) (see FIG. 7F)
Subsequently, in a pattern in which the second electrode (cathode layer 315) of the adjacent light emitting portion and the lead electrode 312a of the first electrode wiped out above (except for the left-most lead electrode) are connected, 5 × 10 ⁻⁴ Pa A mask pattern was formed by vapor deposition using aluminum under vacuum, and a conductive film 316 made of an aluminum layer having a thickness of 100 nm was formed.

[Formation of sealing member] (see FIG. 7G)
(Formation of adhesive layer)
Next, an alignment mark attached to the PET of the produced organic EL element is detected, and the light emitting region and the light emission are removed except for the lead electrode 312a of the first electrode on the left end and the lead portion 313 of the second electrode on the right end according to the position of the alignment mark. An ultraviolet curable liquid adhesive (epoxy resin system) was used around the area, and an adhesive layer 350 was applied with a thickness of 30 μm.

(Lamination of sealing film)
Thereafter, the sealing film (Letter Printing GX film: thickness 100 μm) was prepared by stacking on the adhesive-coated surface of the organic EL element by a roll laminator method, and roll-pressed at a pressure of 0.1 MPa in an atmospheric pressure environment. Then, a high pressure mercury lamp with a wavelength of 365 nm was irradiated and fixed for 1 minute at an irradiation intensity of 5 to ²⁰ mW / cm ² and a distance of 5 to 15 mm, and the sealing film 351 was bonded.

(Cutting) (not shown)
Next, the organic EL panel 1 was manufactured by detecting the alignment mark in the size of the individual organic EL panel in the state in which the plurality of organic EL panels that were produced were continuously connected, and cutting according to the position of the alignment mark. .

<Production of comparison panel>
After forming the organic layer, which is a conventional method, after patterning the organic layer (wiping process), the organic EL panel 2 of the comparative panel was produced by patterning the second electrode and the extracted conductive layer. .

[Evaluation]
For each of the panels 1 and 2 produced, the sample extracted from the end 5 m was tested for the luminance ratio between the central part and the peripheral part of the light emitting region and the dark spot (spot-like non-light emitting part) by the following test method. Evaluation was performed according to the following evaluation rank. The results are shown in Table 1.

Measurement of Brightness Ratio at Center and Peripheral Area Using a constant voltage power source, DC 5V was applied. At that time, in each organic EL element, the brightness at the center and the outer periphery was measured and the ratio was measured. Although there was no difference in the initial luminance ratio, the luminance in the peripheral portion decreased compared with the luminance in the central portion when the current was continued for 100 hours. The decrease in luminance at the peripheral portion was expressed as a relative value.

(Brightness ratio of the central part)
◯: The luminance was within 90% with respect to the central portion. Δ: The luminance was less than 90% and 80% or more with respect to the central portion. X: The luminance was less than 80% with respect to the central portion.

(Measurement method for the number of dark spots (spot-shaped non-light emitting parts))
Using a constant voltage power source, DC 5V was applied to the organic EL panel, and the presence or absence of dark spots was visually observed using a loupe (magnification 8 times). Measurement was performed in the entire light emitting region, and the number of dark spots was visually measured.

Evaluation rank of dark spots (spot-like non-light emitting portions) ◎: No dark spots are generated ○: 1 or more dark spots, less than 5 △: 5 or more dark spots, less than 20 ×: 20 dark spots more than

  The sample of the present invention has good luminance ratio and dark spot characteristics, that is, the wiping patterning method of the present invention shows good results with little contamination by a solvent and adhesion of foreign matter to the light emitting part when the organic layer is removed.

It is sectional drawing of a common organic EL element. The formation by the conventional process of an organic EL element is shown. The formation process of the organic EL element by this invention is shown. It is a top view which shows the formation process of this invention. It is the schematic which shows an example of the wiping apparatus preferably used for this invention. The example of the wiping head of another form was shown. The formation process of the organic EL element of this invention in an Example is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2,12,212,312 Anode layer 3,13,213,313 Lead part 4,14,214,314 Organic layer 5,15,215,315 Cathode layer 6,16,216,316 Conductive layer 10 Dust 11 , 211 Flexible base material 12a, 212a, 312a Lead electrode 17 Alignment mark 230 Wiping head 350 Adhesive layer 351 Sealing film

Claims (8)

(A) One or more organic layers are formed on the entire surface of the substrate using the transparent conductive film formed in a pattern as a first electrode (anode layer + lead portion),
(B) patterning a second electrode (cathode layer) on the organic layer,
(C) removing a part of the organic layer on the predetermined first electrode;
(D) forming a conductive layer over the second electrode and the first electrode portion from which the organic layer has been removed;
A manufacturing method of an organic electroluminescence element characterized by the above. The method for producing an organic electroluminescence element according to claim 1, wherein the portion from which the organic layer is removed is a lead portion of a first electrode provided on the substrate. The method for producing an organic electroluminescent element according to claim 1 or 2, wherein the portion from which the organic layer has been removed is a lead portion of the first electrode and a non-light-emitting portion of the anode layer provided on the substrate. . The method for removing the organic layer uses a solvent capable of dissolving the organic layer, applies the solvent to the removal portion, dissolves the organic layer, and recovers the solution to remove the organic layer. The manufacturing method of the organic electroluminescent element of any one of these. The method for removing the organic layer uses a solvent that dissolves the organic layer, applies the solvent to the removal portion, contacts the wiping member, and dissolves or swells and peels off the organic layer. The manufacturing method of the organic electroluminescent element of any one of these. The method for removing the organic layer is characterized in that a solvent that dissolves the organic layer is used, a solvent is applied to the wiping member, the wiping member is brought into contact with the removal portion, and the organic layer is dissolved or swollen and removed. The manufacturing method of the organic electroluminescent element of any one of Claims 1-3 to do. The method for removing an organic layer physically peels the organic layer, The method for producing an organic electroluminescent element according to any one of claims 1 to 3. The method for manufacturing an organic electroluminescence element according to claim 7, wherein the physically peeling method is a laser ablation method.

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