JP2009163889A - Method for manufacturing functional thin film, and organic electroluminescent luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a functional thin film by a wet process method in which when forming the functional thin film containing an organic compound layer constituted of at least two components of a first component and a second component different in solubility to a solvent, a selection range and a coating condition of the solvent are widened, and an organic electroluminescent illumination luminaire using an organic EL manufactured by this manufacturing method. <P>SOLUTION: In the method for manufacturing the functional thin film having the organic compound layer having at least the first component and the second component on a base material, after coating the first coating liquid on the base material and forming a first coating liquid membrane, while a mass fraction of the first coating liquid membrane is retained at 1.0 to 0.1, the organic compound layer is formed by coating a second coating liquid containing the second component on the first coating liquid membrane, by adding vibrations, and by drying. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a functional thin film including an organic compound layer composed of at least two components of a first component and a second component on a substrate. More specifically, after applying the first coating liquid containing the first component on the substrate to form the first coating liquid film, the second coating liquid containing the second component is applied on the first coating liquid layer. The present invention relates to a method for producing a functional thin film having an organic compound layer formed by applying vibration to a first coating liquid film and a second coating liquid film and drying the film.

  The present invention will be described by taking an organic electroluminescence element (hereinafter also referred to as an organic EL element) as a representative of the functional thin film. In recent years, the use of organic EL elements as light sources for display devices such as flat displays, electrophotographic copying machines, and printers has been studied. In this organic EL element, an anode made of a transparent conductive film such as ITO (Indium tin oxide) is provided on a transparent substrate 1 such as a glass substrate, and an organic compound layer made of a hole transport layer and a light emitting layer is formed thereon, and an anode In this order, cathodes made of aluminum or the like, which are formed in a stripe pattern intersecting with each other, are provided in this order, and an anode and a cathode are provided in the periphery of the pixel portion in which organic EL elements are arranged in a matrix Are connected to an external circuit or an internal drive circuit, and an anode-side extraction electrode and a cathode-side extraction electrode are formed.

  In the organic EL element, each intersection of the anode and the cathode becomes one pixel, a voltage is applied to each organic EL element, electrons are injected from the cathode, and holes are injected from the anode into the organic compound layer. It is known that light emission occurs when electron-hole recombination occurs in a layer.

  An organic EL element is a current-driven light-emitting element that emits light when a very thin thin film of a fluorescent organic compound is sandwiched between an anode and a cathode and a current is applied. Usually, the organic compound is an insulator, but by making the film thickness of the organic compound layer very thin, current injection becomes possible and the organic EL element can be driven. It can be driven at a low voltage of 10 V or less, and it is possible to obtain highly efficient light emission.

  In particular, phosphorescent organic EL devices using excited triplets that far exceed the efficiency of conventional fluorescent light emitting organic EL devices using excited singlets have been disclosed by S.C. R. Forrest et al. (Appl. Phys. Lett. (1999), 75 (1), 4-6). Furthermore, C.I. As reported by Adachi et al. (J. Appl. Phys., 90, 5048 (2001)), such an organic EL device is not limited to a display until the luminous efficiency reaches 60 lm / W. Application to lighting is expected.

  Thin films are widely used as components of various devices such as electronic devices and optical devices. As a method for forming such a thin film, a dry process method and a wet process method are known.

In the dry process method, a thin film is formed under high vacuum. In this case, since it is easy to make a laminated structure, it is very excellent in terms of efficiency and quality. On the other hand, since deposition is performed under a high vacuum condition of 10 ⁻⁴ Pa or less, the operation is complicated and costly. It is not always preferable from the viewpoint of production.

  On the other hand, as the wet process method, various wet methods such as an extrusion coating method, a dip coating method, a spin coating method, an ink jet method, and a printing method can be adopted. In other words, since it can be formed under atmospheric pressure, there is an advantage that the cost can be reduced. Furthermore, since the solution is prepared into a thin film, there is a feature that unevenness is hardly generated even in a large area. Therefore, it is a thin film forming method that is actively used because of its great merit in terms of cost and manufacturing technology. It can be said that this is very advantageous in terms of cost and manufacturing technology for lighting applications of organic EL elements.

  When applying an organic compound layer by a wet process method, the preparation of the coating solution to be used is usually a method in which the material constituting the organic compound layer is dissolved in a solvent by applying shearing force or heat with ultrasonic vibration or a static mixer. Has been done. At that time, while the shearing force is continuously applied, the dissolved state does not become a problem, but there are cases in which aggregation occurs between molecules after a while for a while. This seems to be closely related to the affinity with the solvent.

  The light emitting layer, which is an organic compound layer constituting the organic EL element, is composed of at least a host material and a dopant material. In this case, in addition to the affinity of the host material and the dopant material with the solvent, Since the affinity becomes a problem, the influence on the aggregation of the coating solution becomes more remarkable.

  Many of the host materials and dopant materials constituting the light emitting layer are hardly soluble, and it cannot always be said that the solvent selection range is wide, so dissolving the host material and the dopant material in a common solvent is difficult for both materials. This means that a solvent having sufficient solubility is used, and the solvent selection range becomes extremely narrow. Here, if the solubility of either of the two types of materials is lost, intermolecular aggregation is accelerated, which causes a further decrease in the life of the coating solution. In the case of test piece production, it is possible to complete the work in a relatively short time from the liquid preparation process to the coating process, but in the production scale, the process from the liquid preparation process to the coating process is not always able to be processed in a short time. It may take a long time. In addition, it is not impossible to continue applying sufficient shearing force or heat to the coating liquid to all the liquid feeding lines, but in reality, it is not necessarily good in terms of both equipment and cost.

  As a method for producing an organic EL element by a wet process method, a so-called roll-to-roll method using a roll-like strip-like flexible material and a single wafer method can be mentioned.

  For example, at least a first electrode, a hole transport layer, a light emitting layer, a second organic compound layer, an electron transport layer, a second electrode, and a seal are formed on a strip-shaped flexible substrate in a roll-to-roll manner. A method for forming a light emitting layer forming coating solution prepared by mixing a host material and a dopant material when manufacturing an organic EL panel in which a stop layer is sequentially laminated is described by a wet process method (for example, Patent Documents). 1).

  When manufacturing an organic EL panel in which a first electrode, a hole transport layer, a light emitting layer, an electron transport layer, a second electrode, and a sealing layer are sequentially laminated on a single substrate, a host material and a dopant material are used. A method of forming by a wet process method using a light emitting layer forming coating solution prepared by mixing is described (for example, see Patent Document 2).

However, it has been found that the methods described in Patent Document 1 and Patent Document 2 have the following drawbacks.
1) The light emitting layer forming coating solution for forming the light emitting layer, which is an organic compound layer, uses a host material and a dopant material having different solubility in a solvent, and a solvent having solubility in the host material and the dopant material. Therefore, the solvent selection range is narrow.
2) Since the solvent to be used is limited, the coating conditions are also limited.
3) When the solubility of either the host material or the dopant material is lost, intermolecular aggregation occurs, and long-time coating cannot be performed, resulting in a decrease in production efficiency, which is an advantage of the roll-to-roll method.

From such a situation, an organic compound layer composed of at least two components of the first component and the second component is used by using at least two components of the first component and the second component having different solubility in the solvent. Development of functional thin film by wet process method with wide range of solvent selection and coating conditions when forming functional thin film, and development of organic electroluminescence lighting device using organic EL element manufactured by this manufacturing method Is desired.
JP 2007-149589 A JP 2007-115573 A

  The present invention has been made in view of the above situation, and the object thereof is to use at least two components, ie, a first component and a second component, which have different solubility in a solvent, and at least the first component and the second component. When forming a functional thin film including an organic compound layer composed of two components, a method for producing a functional thin film by a wet process method in which the solvent selection range and coating conditions are expanded, and an organic EL produced by this production method It is providing the organic electroluminescent illuminating device which uses this.

  The above object of the present invention has been achieved by the following constitution.

  1. In the method for producing a functional thin film having an organic compound layer having at least a first component and a second component on a base material, the organic compound layer is formed by applying the first coating liquid on the base material. After the coating liquid film is formed, the second component containing the second component is formed on the first coating liquid film while the mass fraction of the first coating liquid film is maintained at 1.0 to 0.1. 2. A method for producing a functional thin film, which is formed by applying a coating liquid, applying vibration and drying.

  2. The functional thin film is a functional thin film having at least two layers on a substrate, wherein at least one of the two layers has an organic compound layer having a first component and a second component, and the organic The compound layer is formed by applying a first coating liquid containing the first component on the substrate to form a first coating liquid film, and then the mass fraction of the first coating liquid film is 1.0 to 0.1. The second coating liquid containing the second component is applied onto the first coating liquid film, and vibration is applied and dried. 2. A method for producing a functional thin film according to 1.

  3. An organic electroluminescence panel in which the functional thin film sequentially includes at least a first electrode, an organic compound layer having at least two components of a first component and a second component, a second electrode, and a sealing layer on a substrate. The organic compound layer is formed by applying a first coating liquid containing the first component on the first electrode to form a first coating liquid film, and then forming the first coating liquid film. The second coating liquid containing the second component is applied onto the first coating liquid layer, and vibration is applied to the first coating liquid layer while the mass fraction of 1.0 to 0.1 is maintained. 3. The method for producing a functional thin film as described in 2 above, wherein the functional thin film is formed.

  4). 4. The method for producing a functional thin film according to any one of 1 to 3, wherein the second coating liquid is applied by a droplet coating method.

  5). The method for producing a functional thin film according to any one of 1 to 4, wherein the solvent used in the first coating solution has a boiling point of 80 to 210 ° C.

  6). 6. The method for producing a functional thin film according to any one of 3 to 5, wherein the organic compound layer is a light emitting layer having at least a host material and a dopant material.

  7. The method for producing a functional thin film according to any one of 3 to 6, wherein the first component is a host material and the second component is a dopant material.

  8). 8. The method for producing a functional thin film according to any one of 1 to 7, wherein the substrate is a belt-like flexible substrate.

  9. An organic electroluminescence lighting device using the organic electroluminescence panel produced by the method for producing a functional thin film according to any one of 3 to 8.

  A functional thin film including an organic compound layer composed of at least two components of the first component and the second component is formed by using at least two components of the first component and the second component having different solubility in a solvent. At that time, it was possible to provide a method for producing a functional thin film by a wet process method in which the selection range of solvents and coating conditions were expanded, and an organic electroluminescence lighting device using an organic EL element produced by this production method.

  Embodiments of the present invention will be described with reference to FIGS. 1 to 4, but the present invention is not limited thereto. In addition, an organic EL panel is mentioned as a representative of the functional thin film, and the method for manufacturing the organic EL panel will be described.

  FIG. 1 is a schematic view showing an example of an organic EL panel used for illumination. FIG. 1A is a schematic perspective view showing an example of an organic EL panel. FIG.1 (b) is a schematic sectional drawing in alignment with AA 'of Fig.1 (a). FIG.1 (c) is a schematic sectional drawing in alignment with BB 'of Fig.1 (a).

  In the figure, 1 indicates an organic EL panel. The organic EL panel 1 includes an anode (first electrode) 102, a hole transport layer 103, a light emitting layer 104, a cathode buffer layer (electron injection layer) 105, a cathode ( (Second electrode) 106, an adhesive layer 107, and a sealing member 108. A sealing layer is formed by the adhesive layer 107 and the sealing member 108. The organic EL panel 1 includes an adhesion sealing structure that is sealed by an adhesive layer 107 except for an end portion of the extraction electrode 102a of the anode (first electrode) 102 and the extraction electrode 106a of the cathode (second electrode) 106. It has become. A gas barrier film (not shown) may be provided between the anode (first electrode) 102 and the flexible substrate 101. In the present invention, the state where the second electrode is sealed with the sealing member 108 is referred to as an organic EL panel, and the state where the second electrode 106 is formed is referred to as an organic EL element.

  In this figure, as an organic compound layer composed of at least a first component and a second component, for example, a light emitting layer 104 having at least a dopant material as a first component and a host material as a second component is exemplified. It is done.

  The layer configuration of the organic EL panel shown in this figure is an example, but the following configuration is another typical layer configuration between the anode (first electrode) and the cathode (second electrode). Can be mentioned.

(1) Anode (first electrode) / organic compound layer (light emitting layer) / cathode (second electrode)
(2) Anode (first electrode) / organic compound layer (light emitting layer) / electron transport layer / cathode (second electrode)
(3) Anode (first electrode) / hole transport layer / organic compound layer (light emitting layer) / hole blocking layer / electron transport layer / cathode (second electrode)
(4) Anode (first electrode) / hole transport layer (hole injection layer) / organic compound layer (light emitting layer) / hole blocking layer / electron transport layer / cathode buffer layer (electron injection layer) / cathode (first) 2 electrodes)
(5) Anode (first electrode) / anode buffer layer (hole injection layer) / hole transport layer / organic compound layer (light emitting layer) / hole blocking layer / electron transport layer / cathode buffer layer (electron injection layer) / Cathode (second electrode)
In the case of the organic EL panel shown in this figure, the place where the organic compound layer composed of at least the first component and the second component is formed is, for example, the anode shown in (1) and (2). On the (first electrode), on the hole transport layer (hole injection layer) formed on the anode (first electrode) shown in (3) and (4), and the anode shown in (5) A hole transport layer formed on (first electrode) can be mentioned. Each layer constituting the organic EL panel will be described later.

  FIG. 2 is a schematic diagram showing an example of a manufacturing process for manufacturing the organic EL panel shown in FIG. 1 using a strip-shaped flexible substrate.

  This figure shows a light emitting layer as an example of an organic compound layer composed of at least two components of a first component and a second component, and a coating liquid for forming the light emitting layer is a first coating liquid containing the first component, It shows a case where the light emitting layer is formed by coating separately with the second coating liquid containing the second component. The first component is a host material, and the second component is a dopant material.

  In the figure, reference numeral 2 denotes a manufacturing process of the organic EL panel. Manufacturing process 2 includes a strip-shaped flexible substrate supplying process 201, a first electrode forming process 202, a hole transport layer forming process 203, a light emitting layer forming process 204, and a cathode buffer layer (electron injection layer). It includes a forming step 205, a second electrode forming step 206, a sealing step 207, and a cutting step 208.

  From the supply step 201, the strip-shaped flexible substrate 3 is fed out and supplied. Reference numeral 301 denotes a roll-shaped strip-shaped flexible substrate prepared in the supply device. The supply process 201 uses a belt-shaped flexible substrate feeding device (not shown) wound up in a roll shape, and is continuously applied to the first electrode forming process 202 of the next process. 3 is fed out through the transport roller 201b. It is preferable that an alignment mark (not shown) for determining a position where the first electrode is formed is attached to the strip-shaped flexible substrate 3 in advance.

  The first electrode forming step 202 has a winding portion 202d, and uses a vapor deposition apparatus 202a having an evaporation source container 202b and an accumulator 202c. The accumulator 202c has a plurality of lower conveyance rollers 202c1 and a plurality of upper conveyance rollers 202c2, and is arranged for speed adjustment with the supply step 201. The winding unit 202d uses a winding device (not shown) and an accumulator 202d1. The accumulator 202d1 has a plurality of lower conveyance rollers 202d11 and a plurality of upper conveyance rollers 202d12. The accumulator 202d1 has a first electrode formation speed in the vapor deposition apparatus 202a and a winding speed in a winding apparatus (not shown). Arranged for speed adjustment.

  In the first electrode forming step 202, an alignment mark (not shown) attached to the strip-like flexible substrate 3 continuously supplied from the supply step 201 is read by a detection device (not shown), and the detection device (not shown) A mask pattern is formed on a first electrode (not shown, corresponding to the first electrode 102 in FIG. 1) having an extraction electrode at a position determined by the vapor deposition apparatus 202a according to information (not shown). The thickness of the first electrode is preferably 100 nm to 200 nm. After the first electrode is formed, it is preferable to temporarily take up and temporarily store it via a conveying roller 202d2 by a winding device (not shown). Then, it is sent to the hole transport layer forming step 203. 3a shows the strip | belt-shaped flexible base material by which even the 1st electrode wound up by the winding apparatus (not shown) and became roll shape was laminated | stacked.

  The supply process 201 and the first electrode positive formation process 202 need to be performed continuously in a vacuum environment. “Continuously performing” means that the winding portion between the supplying step 201 and the first electrode forming step 202 is placed in a vacuum environment. In addition, although the case where the 1st electrode formation process is formed with a vapor deposition method is shown in this figure, there is no limitation in particular about a formation method, For example, sputtering method etc. can be used.

  The hole transport layer forming step 203 includes a feeding unit 203a, a coating unit 203b, and a drying unit 203c. In the hole transport layer forming step 203, the hole transport layer forming coating solution is formed on the first electrode except for the first electrode take-out electrode portion of the strip-shaped flexible base material 3a formed up to the first electrode. After being applied, a hole transport layer (not shown, corresponding to the hole transport layer 103 in FIG. 1) is formed through the drying unit 203c, and subsequently conveyed to the light emitting layer forming step 204. It is also possible to take up and store once if necessary. Incidentally, the hole transport layer forming step 203 in this figure is arranged in an atmospheric pressure environment.

In the feeding portion 203a, the first electrode is already formed, and the strip-shaped flexible base material 3a wound in a roll wound around the winding core is supplied via the transport roller 203a1. . An accumulator 203a2 and an antistatic means 203a3 can be disposed between the feeding unit 203a and the coating unit 203b as necessary. The accumulator 203a2 has a plurality of lower conveyance rollers 203a21 and a plurality of upper conveyance rollers 203a22, and is arranged for speed adjustment in the application unit 203b. The antistatic means 203a3 has a non-contact type antistatic device 203a31 and a contact type antistatic device 203a32. Examples of the non-contact type antistatic device 203a31 include a non-contact type ionizer. The type of ionizer is not particularly limited, and the ion generation method may be either an AC method or a DC method. An AC type, a double DC type, a pulsed AC type, and a soft X-ray type can be used, but the AC type is particularly preferable from the viewpoint of precise static elimination. Air or N ₂ is used as the injection gas required when using the AC type, but it is preferable to use N ₂ with sufficiently high purity. From the viewpoint of in-line operation, the blower type or the gun type is selected.

  As the contact-type antistatic device 203a32, a static eliminating roll or a conductive brush connected to the ground is used. The static elimination roll as the static eliminator is grounded and removes the surface charge by rotatingly contacting the neutralized surface. Such static elimination rolls include rolls made of elastic plastic or rubber mixed with conductive materials such as carbon black, metal powder, and metal fibers in addition to rolls made of metal such as aluminum, copper, nickel, and stainless steel. used. In particular, an elastic material is preferable in order to improve contact with the belt-like flexible substrate 3a. Examples of the conductive brush connected to the earth include a neutralizing bar or a neutralizing yarn structure having a brush member made of conductive fibers arranged in a line or a linear metal brush. The neutralization bar is not particularly limited, but a corona discharge type is preferably used. For example, SJ-B manufactured by Keyence Corporation is used. There is no particular limitation on the static elimination yarn, but usually a flexible yarn is preferably used. For example, 12/300 × 3 manufactured by Naslon can be cited as an example.

  The non-contact type antistatic device 203a31 is used on the surface side of the hole transport layer formed on the strip-like flexible substrate 3a, and the contact type antistatic device 203a32 is on the back side of the strip-like flexible substrate 3a. It is preferable to use for.

  The coating unit 203b uses a wet coating machine 203b1 and a backup roll 203b2 that holds a strip-shaped flexible base material 3a on which the first electrode (anode) is formed. The coating liquid for forming a hole transport layer by the wet coater 203b1 uses an alignment mark (not shown) attached to the strip-shaped flexible substrate 3a on which the first electrode (anode) is formed. The first electrode (anode) is detected and applied to the first electrode (anode) except for the first electrode (anode) take-out electrode (not shown, corresponding to the take-out electrode 102a in FIG. 1). The thickness of the hole transport layer is about 5 nm to 5 μm, preferably 5 to 200 nm.

  In addition, although this figure has shown the case of the whole surface coating type die coating system as a wet coating machine, other than this, for example, a screen printing system, a flexographic printing system, an inkjet system, a Mayer bar system, a cap coating method, a spraying method It is possible to use a coating machine such as a coating method, a casting method, a roll coating method, a bar coating method, or a gravure coating method. The use of these wet coaters can be appropriately selected according to the material of the hole transport layer.

  The drying unit 203c includes a drying device 203c1 and a heat treatment device 203c2, and heats the hole transport layer from the back surface side of the belt-like flexible substrate by the back surface heat transfer method. As the heat treatment conditions for the hole transport layer in the heat treatment apparatus 203c2, the smoothness of the hole transport layer is improved, the residual solvent is removed, the hole transport layer is cured, and the glass transition temperature of the hole transport layer is considered. Therefore, it is preferable to perform the back surface heat transfer type heat treatment at a temperature not exceeding the decomposition temperature of the organic compound constituting the hole transport layer at -30 to + 30 ° C.

  In the light-emitting layer forming step 204, a light-emitting layer (not shown, corresponding to the light-emitting layer 104 in FIG. 1) is formed on the hole-transporting layer of the strip-shaped flexible substrate 3a formed up to the hole-transporting layer. Once wound up and stored. Incidentally, the light emitting layer forming step 204 in this figure is arranged in an atmospheric pressure environment.

  The light emitting layer forming step 204 includes a first application unit 204a, a second application unit 204b, a drying unit 204c, and a winding unit 204d. In the first coating unit 204a, the first coating liquid containing the first component constituting the light emitting layer is coated on the hole transport layer by the first wet coating machine 204a3 to form a first coating liquid film, and the second coating unit In 204b, the second coating liquid containing the second component constituting the light emitting layer is formed on the first coating liquid film while the mass fraction of the first coating liquid film is maintained at 1.0 to 0.1. A second wet coating machine 204b1 is applied to form a second coating liquid film. While maintaining the mass fraction of 1.0 to 0.1, the mass when the first coating film is formed is 1.0, the solvent evaporates and the mass forms the first coating film. It means the time until it becomes 0.1 with respect to the mass when it is done.

  The first coating unit 204a is placed between the drying unit 203c of the hole transport layer step 203 and the backup roll 204a4 that holds the accumulator 204a1, the antistatic means 204a2, the first wet coating unit 204a3, and the strip-shaped flexible substrate 3a. And have. The accumulator 204a1 has a plurality of lower conveyance rollers 204a11 and a plurality of upper conveyance rollers 204a12, and is arranged for speed adjustment in the first application unit 204a and the second application unit 204b. The antistatic means 204a2 has a non-contact type antistatic device 204a11 and a contact type antistatic device 204a12. The antistatic means 204a2 uses the same type of antistatic device as the antistatic means 203a3.

  The first coating liquid by the first wet coater 204a3 detects an alignment mark (not shown) attached to the belt-shaped flexible substrate 3a by an alignment mark detector (not shown), and the first electrode (anode) ) Is applied on the hole transport layer already formed except for the extraction electrode. As a usable wet coater, it is possible to use the same type of wet coater as the wet coater 203b1 used in the coating section 203b of the hole transport layer forming step 203. In addition, although this figure has shown the case of the whole surface coating type die coating system as a wet coating machine, other than this, for example, a screen printing system, a flexographic printing system, an inkjet system, a Mayer bar system, a cap coating method, a spraying method It is possible to use a coating machine such as a coating method, a casting method, a roll coating method, a bar coating method, or a gravure coating method. The use of these wet coaters can be appropriately selected according to the material of the hole transport layer.

  The second coating unit 204b includes a second wet coating machine 204b1, a holding base 204b2 for horizontally holding the strip-shaped flexible base material 3a formed up to the first coating liquid film, and a vibration applying unit 204b3. ing.

  In the 2nd application part 204b, after applying the 2nd application liquid containing the 2nd ingredient on the formed 1st application liquid film and forming the 2nd application liquid film, the 1st application liquid film is given by vibration giving means 204b3. And vibration are added to the second coating liquid film. By applying vibration, the first coating liquid film and the second coating liquid film are mixed to form a light emitting layer.

  As the second wet coater 204b1, it is possible to use the same coater as the first wet coater 204b3. The second wet coater 204b1 is applied in a discrete manner or a film shape depending on the ratio of the second component in the second coating solution. It is possible to select. When applying in a discrete manner, a droplet application method represented by an ink jet method is preferable.

  Discrete application refers to application in a state where the droplets that have landed do not contact each other and the required droplet density is maintained.

  In the case of the light emitting layer, the host material is preferably 10 nm to 100 nm in view of light emitting performance and quality stability, and the first coating liquid film in which the host material is dissolved according to the solid content concentration of the coating liquid. What is necessary is just to supply.

  The mixing ratio of the dopant material to the host material is 1 to 10%, and the dry film thickness is preferably 0.1 nm to 10 nm. The second coating liquid film in which the dopant material is dissolved according to the solid concentration of the coating liquid is used. What is necessary is just to supply.

  The vibration applying means 204b3 is not particularly limited as long as vibration of 20 kHz to 1000 kHz can be applied to the first coating liquid film and the second coating liquid film. For example, an ultrasonic oscillator, a high frequency ultrasonic oscillator, or the like can be used. Can be mentioned.

  This figure shows the case where the vibration applying means 204b3 is disposed on the downstream side with respect to the second wet coater 204b1, but vibration is added when the second wet coating machine 204b1 applies the second coating liquid. You may arrange | position so that it can do. In this case, for example, the vibration applying means 204b3 may be disposed on the holding base 204b2. Further, the vibration applying means 204b3 may be disposed in the drying device 204c1 and dried while applying vibration.

  The drying unit 204c has a drying device 204c1 and a heat treatment device 204c2, and heats the light emitting layer from the back surface side of the strip-shaped flexible substrate 3a by the back surface heat transfer method. As the heat treatment conditions of the light emitting layer in the heat treatment apparatus 204c2, considering the smoothness improvement of the light emitting layer, the removal of the residual solvent, the curing of the light emitting layer, etc. In addition, it is preferable to perform heat treatment of the backside heat transfer system at a temperature not exceeding the decomposition temperature of the organic compound constituting the light emitting layer.

  When the light emitting layer is a multilayer, it is necessary to arrange units of the first application unit 204a, the second application unit 204b, and the drying unit 204c in accordance with the number of layers to be stacked. For example, a white element can be manufactured by forming a light emitting layer in multiple layers. In the present invention, the light emitting layer refers to a blue light emitting layer, a green light emitting layer, and a red light emitting layer. There is no restriction | limiting in particular as a lamination order in the case of laminating | stacking a light emitting layer, You may have a nonluminous intermediate | middle layer between each light emitting layer. In the present invention, it is preferable that at least one blue light emitting layer is provided at a position closest to the anode among all the light emitting layers. Also, when four or more light emitting layers are provided, for example, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting layer, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting from the order close to the anode. Layered / green light emitting layer, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting layer / green light emitting layer / red light emitting layer, etc. It is preferable for improving luminance stability.

  The total thickness of the light emitting layer is not particularly limited, but is usually selected in the range of 2 nm to 5 μm, preferably 2 nm to 200 nm in consideration of the film homogeneity, the voltage required for light emission, and the like. Further, it is preferably in the range of 10 nm to 20 nm. A film thickness of 20 nm or less is preferable because it has the effect of improving the stability of the emission color with respect to the driving current as well as the voltage surface. The film thickness of each light emitting layer is preferably selected in the range of 2 nm to 100 nm, and more preferably in the range of 2 nm to 20 nm. Although there is no restriction | limiting in particular about the film thickness relationship of each light emitting layer of blue, green, and red, It is preferable that the blue light emitting layer (the sum total when there are two or more layers) is the thickest among three light emitting layers.

  In the winding unit 204d, an antistatic means 204d1 and an accumulator 204d2 are preferably disposed between the drying unit 204c and a winding device (not shown). The antistatic means 204d1 is the same type of antistatic device as the antistatic means 204a2.

  The accumulator 204d2 has a plurality of lower conveyance rollers 204d21 and a plurality of upper conveyance rollers 204d22, and is arranged for speed adjustment in the winding unit 204d.

  In the winding unit 204d, a strip-shaped flexible substrate 3a on which a light emitting layer (not shown, corresponding to the light emitting layer 104 in FIG. 1) is formed by a winding device is wound in a roll shape via a transport roller 204d3. Taken and stored. Then, it is sent to the cathode buffer layer (electron injection layer) forming step 205.

  The cathode buffer layer (electron injection layer) formation step 205 includes a feeding portion 205a of the strip-shaped flexible base material 3a formed up to the light emitting layer wound up in a roll shape, and an evaporation source container 205c. A device 205b and an accumulator 205d are used. The accumulator 205d has a plurality of lower conveyance rollers 205d1 and a plurality of upper conveyance rollers 205d2, and is disposed between the feeding unit 205a and the vapor deposition device 205b. It is arranged for speed adjustment. In the cathode buffer layer (electron injection layer) forming step 205, the alignment is attached to the strip-shaped flexible substrate 3a on which the light emitting layer continuously supplied from the feeding portion 205a through the transport roller 205a1 is formed. A mark (not shown) is read by a detection device (not shown), the take-out electrode is removed at a position determined by the vapor deposition device 205b according to information of the detection device (not shown), and a cathode buffer is formed on the already formed light emitting layer. A layer (electron injection layer) (not shown, corresponding to the cathode buffer layer (electron injection layer) 105 in FIG. 1) is formed into a mask pattern. The thickness of the cathode buffer layer (electron injection layer) is preferably in the range of 0.1 nm to 5 μm.

  In the second electrode forming step 206, a vapor deposition apparatus 206a having an evaporation source container 206b and an accumulator 206c are used. The accumulator 206c has a plurality of lower transport rollers 206c1 and a plurality of upper transport rollers 206c2, and is disposed between the cathode buffer layer (electron injection layer) forming step 205 and the second electrode forming step 206. The cathode buffer layer (electron injection layer) forming step 205 is provided for speed adjustment.

  In the second electrode forming step 206, the second electrode forming step 206 is attached to the strip-shaped flexible substrate 3 a on which the cathode buffer layer (electron injection layer) continuously supplied from the cathode buffer layer (electron injection layer) forming step 205 is formed. An alignment mark (not shown) is read by a detection device (not shown), and the extraction electrode (not shown, corresponding to the extraction electrode 106a in FIG. 1) is positioned at a position determined by the vapor deposition device 206a according to information of the detection device (not shown). A second electrode (cathode) (not shown, corresponding to the second electrode (cathode) 106 of FIG. 1) having a cathode buffer layer (electron injection layer) (not shown, FIG. 1) already formed. A mask pattern is formed on the cathode buffer layer (electron injection layer) 105). The sheet resistance as the second electrode (cathode) is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. At this stage, an organic EL device having a configuration of base material / first electrode (anode) / hole transport layer / light emitting layer / cathode buffer layer (electron injection layer) / second electrode (cathode) is completed.

  This figure shows the case where the cathode buffer layer (electron injection layer) forming step 205 and the second electrode (cathode) forming step 206 are vapor deposition apparatuses, but the cathode buffer layer (electron injection layer) and the second electrode (cathode). There is no particular limitation on the formation method, for example, dry sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma polymerization method, plasma CVD. Method, laser CVD method, thermal CVD method and the like can be used. The cathode buffer layer (electron injection layer) can also use a wet coating method.

  The sealing step 207 includes a sealing member supply step 207b, which uses a sealant coating device 207a, a bonding device 207c, and an accumulator 207e. The sealing member 207b1 is sent from the sealing member supply step 207b. The accumulator 207e has a plurality of lower conveyance rollers 207e1 and a plurality of upper conveyance rollers 207e2, and is arranged for speed adjustment with the second electrode (cathode) forming step 206.

  An alignment mark (not shown) is attached at the same position as the alignment mark (not shown) attached to the strip-shaped flexible substrate 3a on which the second electrode (cathode) is also formed on the sealing member 207b1. It has been.

  In the sealing step 207, an alignment mark (not shown) attached to the band-shaped flexible substrate 3a formed up to the second electrode (cathode) is read by a detection device (not shown), and the detection device (not shown). The sealant coating device 207a is applied to the top and the periphery of the organic EL element except for the extraction electrodes (not shown, corresponding to the extraction electrode 102a and the extraction electrode 106a in FIG. 1).

  Thereafter, an alignment mark (not shown) attached to the strip-shaped flexible substrate 3a having a plurality of organic EL elements is aligned with an alignment mark (not shown) of the sealing member 207b1 by the bonding apparatus 207c. The organic EL element is tightly sealed. At this stage, an organic EL panel is manufactured. Since the organic EL panels produced at this stage are continuously connected, they are cut into individual organic EL panels in a cutting step 208.

  The cutting process 208 uses a cutting device 208a, an accumulator 208b, and a collection box 208c. The accumulator 208 b has a plurality of lower conveyance rollers 208 b 1 and a plurality of upper conveyance rollers 208 b 2, and is arranged for speed adjustment with the sealing step 207. In the cutting device 208a, a detection device (not shown) detects an alignment mark (not shown) attached to the strip-shaped flexible substrate 3a on which a plurality of organic EL panels are formed or an alignment mark (not shown) of the sealing member 207b1. And is cut and punched according to information from a detection device (not shown), and collected as an individual organic EL panel 4 in a collection box 208b.

  This figure shows a case where the first electrode formation, hole transport layer formation to light-emitting layer formation, and cathode buffer layer (electron injection layer) formation to cutting are divided into three steps. It is also possible to carry out continuously by connecting up to cutting. The cut organic EL panel has the same configuration as the organic EL panel shown in FIG.

  In this figure, the light emitting layer formation and the hole transport layer formation are performed by a wet method, and the other layers are a dry method, and a method for manufacturing an organic EL panel is shown, but a cathode buffer layer (electron injection layer) It is also possible to carry out up to the wet method. In that case, using the same process as the hole transport layer 203 shown in the figure, after sequentially stacking the hole transport layer, the light emitting layer, the cathode buffer layer (electron injection layer) on the first electrode, After the second electrode is formed and the organic EL element is manufactured, the individual organic EL is sealed and sealed in the same process as the sealing process 207 shown in the figure, and is sealed in the same process as the cutting process 208 shown in the figure. Panels can be manufactured.

  FIG. 3 is a schematic diagram showing an example of a manufacturing process for manufacturing the organic EL panel shown in FIG. 1 using a single-wafer substrate.

  In the drawing, the light emitting layer is cited as an example of an organic compound layer composed of at least two components, ie, the first component and the second component, and the first coating containing the first component is used as the coating liquid for forming the light emitting layer. It shows a case where the light emitting layer is formed by separately applying the liquid and the second coating liquid containing the second component. The first component is a host material, and the second component is a dopant material. Further, since the first electrode already formed on the single-wafer substrate is used, the first electrode forming step is omitted.

  In the figure, reference numeral 4 denotes a manufacturing process of the organic EL panel. The manufacturing process 4 includes a sheet substrate supply process 401, a hole transport layer forming process 402, a light emitting layer forming process 403, a cathode buffer layer (electron injection layer) forming process 404, a second electrode forming process 405, A sealing process 406 and a cutting process 407 are included. In the manufacturing process shown in this figure, a supply process 401 to a light emitting layer forming process 403, a sealing process 4068, and a cutting process 407 are performed under atmospheric pressure conditions, and a cathode buffer layer (electron injection layer) forming process 404 is performed. And the second electrode forming step 405 are continuously performed under reduced pressure conditions.

From the supply step 401, the single-wafer substrate 5 on which at least one first electrode used to form at least one organic EL panel is already supplied to the next hole transport layer formation step 402 by the supply device 401a. Is done. It is preferable that an alignment mark (not shown) for indicating the position of the first electrode is previously attached to the single-wafer substrate 5 on which the first electrode has already been formed. Reference numeral 401b denotes a substrate cleaning apparatus for cleaning the surface of the single-wafer substrate 5 on which at least one first electrode has already been formed. For example, a low-pressure mercury lamp, an excimer lamp, or a plasma cleaning apparatus is preferably used as the substrate cleaning processing apparatus 401b. As conditions for the cleaning surface modification treatment using a low-pressure mercury lamp, for example, a cleaning surface modification treatment is performed by irradiating a low-pressure mercury lamp with a wavelength of 184.2 nm at an irradiation intensity of 5 to ²⁰ mW / cm ² and a distance of 5 to 15 mm. Conditions are mentioned. For example, atmospheric pressure plasma is preferably used as the condition for the cleaning surface modification treatment by the plasma cleaning apparatus. Examples of the cleaning conditions include conditions in which a gas containing oxygen of 1 to 5% by volume is used for argon gas, and the cleaning surface modification treatment is performed at a frequency of 100 KHz to 150 MHz, a voltage of 10 V to 10 KV, and an irradiation distance of 5 to 20 mm.

  The hole transport layer forming step 402 includes a coating part 402a and a drying part 402b. In the hole transport layer forming step 402, a coating liquid for forming a hole transport layer is applied on the first electrode except for the take-out electrode part of the first electrode of the single-wafer substrate 5 on which the first electrode is formed, and a drying part. Through 402b, a hole transport layer (not shown, corresponding to the hole transport layer 103 in FIG. 1) is formed and subsequently conveyed to the light emitting layer forming step 403. It is also possible to store it once if necessary.

  The coating unit 402a includes a wet coating machine 402a1 and a holding base 402a2 that horizontally holds the single-wafer base material 5 on which the first electrode is formed. The wet coater 402a1 is not particularly limited. For example, a die coating method, a screen printing method, a flexographic printing method, an ink jet method, a Mayer bar method, a cap coating method, a spray coating method, a casting method, a roll coating method, a bar coating method, and a gravure. A coating machine such as a coating method can be used. The use of these wet coaters can be appropriately selected according to the material of the hole transport layer. It is preferable to apply so that the thickness after drying is 10 to 100 nm.

  The drying unit 402b includes a drying device 402b1 having a drying air supply port 402b2, an exhaust port 402b3, and a transporting roll 402b4. The drying device 402b1 preferably has a function capable of heat treatment. As the heat treatment conditions, the hole transport layer is improved in consideration of improvement of the smoothness of the hole transport layer, removal of the residual solvent, curing of the hole transport layer, and the like. It is preferable to perform the back surface heat transfer type heat treatment at −30 to + 30 ° C. with respect to the glass transition temperature of the transport layer and at a temperature not exceeding the decomposition temperature of the organic compound constituting the hole transport layer.

  In the light emitting layer forming step 403, a light emitting layer (not shown, corresponding to the light emitting layer 104 in FIG. 1) is formed on the hole transport layer of the single-wafer substrate 5 on which the hole transport layer is formed. The cathode buffer layer (electron injection layer) forming step 404 in the process is transported. It is also possible to store it once if necessary.

  The light emitting layer forming step 403 includes a first application unit 403a, a second application unit 403b, and a drying unit 403c. The first coating unit 403a includes a first wet coating machine 403a1, a holding table 403a2 for horizontally holding the single-wafer base material 5 on which the hole transport layer is formed, and a transport device 403a3.

  In the first coating unit 403a, a first coating liquid containing a first component constituting the light emitting layer is coated on the hole transport layer by a first wet coating machine 403a1 to form a first coating liquid film, and a second coating unit In 403b, the second coating liquid containing the second component constituting the light emitting layer is formed on the first coating liquid film while the mass fraction of the first coating liquid film is maintained at 1.0 to 0.1. A second wet coating machine 403b1 is applied to form a second coating liquid film. While the mass fraction is maintained at 1.0 to 0.1, the mass when the first coating film is formed is 1.0, the solvent evaporates and the mass of the first coating film is It means between 0.1 and the mass when formed.

  The first coating liquid from the first wet coater 403a1 detects an alignment mark (not shown) attached to the single-wafer substrate 5 with an alignment mark detector (not shown), and the first electrode (anode) It is applied on the hole transport layer already formed except for the extraction electrode. As a usable wet coater, it is possible to use the same type of wet coater as the wet coater 402a1 used in the coating section 402a of the hole transport layer forming step 402. Use of these wet applicators can be appropriately selected according to the first coating liquid containing the first component.

  The second coating unit 403b includes a second wet coating machine 403b1, a holding base 403b2 that horizontally holds the single-wafer base material 5 on which the first coating liquid film has been formed, a transport device 403b3, and a vibration applying unit 403b4. have.

  In the 2nd application part 403b, the alignment mark (not shown) attached to the base material 5 of a sheet | seat is detected with an alignment mark detector (not shown), and it is 2nd on the formed 1st coating liquid film. After applying the second coating liquid containing the component to form the second coating liquid film, vibration is applied to the first coating liquid film and the second coating liquid film by the vibration applying means 403b4. By applying vibration, the first coating liquid film and the second coating liquid film are mixed to form a light emitting layer.

  As the second wet coater 403b1, it is possible to use the same coater as the first wet coater 403a. The second wet coater 403b1 is applied discretely or in a film form depending on the ratio of the second component in the second coating liquid. It is possible to select. When applying in a discrete manner, a droplet application method represented by an ink jet method is preferable. Discrete application refers to application in a state where the droplets that have landed do not contact each other and the required droplet density is maintained.

  In the case of the light emitting layer, the host material is preferably 10 nm to 100 nm in view of light emitting performance and quality stability, and the first coating liquid film in which the host material is dissolved according to the solid content concentration of the coating liquid. What is necessary is just to supply.

  The mixing ratio of the dopant material to the host material is 1 to 10%, and the dry film thickness is preferably 0.1 nm to 10 nm. The second coating liquid film in which the dopant material is dissolved according to the solid concentration of the coating liquid is used. What is necessary is just to supply.

  As the vibration applying means 403b4, the same vibration applying means 204b3 shown in FIG. 2 can be used.

  This figure shows the case where the vibration applying means 403b4 is disposed on the downstream side with respect to the second wet coater 403b1, but the vibration is applied when the second wet coating machine 403b1 applies the second coating liquid. You may arrange | position so that it can do. In this case, for example, the vibration applying means 403b4 may be disposed on the holding base 403b2. Further, the vibration applying means 403b4 may be disposed in the drying device 403c1 and drying may be performed while applying vibration.

  The drying unit 403c includes a drying device 403c1 having a drying air supply port 403c2, an exhaust port 403c3, and a transport roll 403c4. The drying device 403c1 preferably has a function capable of performing heat treatment. As the heat treatment conditions, the glass transition temperature of the light emitting layer is considered in consideration of improvement in smoothness of the light emitting layer, removal of residual solvent, curing of the light emitting layer, and the like. On the other hand, it is preferable to perform the back surface heat transfer type heat treatment at a temperature not exceeding -30 to + 30 ° C. and not exceeding the decomposition temperature of the organic compound constituting the light emitting layer.

  In the cathode buffer layer (electron injection layer) forming step 404, a vapor deposition apparatus 404a1 having an evaporation source container 404a2 is used. In the cathode buffer layer (electron injection layer) formation step 404, an alignment mark (not shown) attached to the single-sided substrate 5 on which the light emitting layer is formed is detected by an alignment mark detector (not shown), An electron injection layer is formed on the light emitting layer formed under reduced pressure conditions.

  The second electrode forming step 405 uses a vapor deposition apparatus 405a1 having an evaporation source container 405a2. In the second electrode formation step 405, an alignment mark detector (not shown) detects an alignment mark (not shown) attached to the single substrate 5 on which the cathode buffer layer (electron injection layer) is formed. The second electrode is formed on the cathode buffer layer (electron injection layer) formed under reduced pressure so as to be orthogonal to the first electrode. The sheet resistance as the second electrode (cathode) is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. At this stage, an organic EL device having a configuration of base material / first electrode (anode) / hole transport layer / light emitting layer / cathode buffer layer (electron injection layer) / second electrode (cathode) is completed. In this figure, the cathode buffer layer (electron injection layer) forming step 205 and the second electrode (cathode) forming step 405 are shown as vapor deposition apparatuses. However, the cathode buffer layer (electron injection layer) and the second electrode (cathode) are shown. There is no particular limitation on the formation method, for example, dry sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma polymerization method, plasma CVD. Method, laser CVD method, thermal CVD method and the like can be used. The cathode buffer layer (electron injection layer) can also use a wet coating method.

  The sealing step 406 includes a sealant coating part 406a and a sheet-like flexible sealing member bonding part 406b. A sealing step 406 shown in the figure shows a step of using a single-sheet flexible sealing member. In the sealant coating section 406a, the single-wafer base material 5 on which the second electrodes are formed is held on the holding base 406a1, and is attached to the single-wafer base material 5 on which the second electrodes are formed. An alignment mark (not shown) is detected by an alignment mark detector (not shown), and a sealing agent is applied around the light emitting area or the light emitting area by the sealant applying device 406a2.

  In the sheet-like flexible sealing member bonding unit 406b, a stacking device 406b1 for stacking the sheet-like flexible sealing member 6 on the sheet substrate on which the sealing agent is coated, And a combination device 406b2.

  In the stacking device 406b1, the single-wafer base material coated with the sealant in the sealant coating unit 406a is placed on the holding base 406b11, and the single-sheet sheet-like flexible sealing member 6 is stacked. Then, it bonds by the bonding apparatus 406b2. In this figure, the case where the sealing step 406 uses a sheet-like flexible sealing member is shown, but a sealing layer may be formed by vapor deposition.

  In the cutting step 407, unnecessary portions of the bonded flexible sealing member were removed, and the flexible sealing member was bonded onto the second electrode except for the end portions of the first electrode and the second electrode. An individual organic EL panel that is made into a state by forming at least one organic EL panel for illumination (surface emission) on a single-wafer base material, and then sealing with a flexible sealing member by a punching and cutting device 407a. The organic EL panel 7 is recovered by punching and cutting.

  The first coating liquid used in the light emitting layer forming step shown in FIGS. 2 and 3 is a coating liquid in which a host material is dissolved in a solvent, and the boiling point of the solvent used is that of the first coating liquid film and the second coating liquid. In consideration of the miscibility with the coating film and the removability of the solvent in the drying step, 80 ° C. to 210 ° C. is preferable. Preferred solvents include, for example, cyclohexane, tetralin, decalin, toluene, o-xylene, m-xylene, p-xylene, 1,2-dichloroethane, 1,4-dichlorobenzene, 1,1,2-trichloroethane, isopropyl alcohol, Examples include 1,4-dioxane, anisole, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, acetonitrile, N-methylpyrrolidone, pyridine, benzonitrile, N, N-dimethylformamide, dimethyl sulfoxide, dimethylacetamide and the like.

  The second coating liquid is a coating liquid in which a dopant material is dissolved in a solvent, and the solvent used is preferably compatible with the solvent used in the first coating liquid.

  The solid content concentration of the first coating solution is preferably 0.1% by mass to 10% by mass in consideration of intermolecular interaction, coating stability, and the like.

  The solid content concentration of the second coating solution is preferably 0.1% by mass to 1% by mass in consideration of intermolecular interaction, coating stability, and the like.

  FIG. 4 is a schematic diagram showing a flow until the second coating liquid film applied on the first coating liquid film in the light emitting layer forming step shown in FIG. 2 is mixed. FIG. 4A is a schematic diagram showing a flow until the second coating liquid film applied in a film shape is mixed on the first coating liquid film in the light emitting layer forming step shown in FIG. FIG. 4B is a schematic diagram showing a flow until the second coating liquid film applied discretely is mixed on the first coating liquid film in the light emitting layer forming step shown in FIG.

  A description will be given with reference to the flow shown in FIG.

  Step 1 is a belt-like shape in which the first electrode 4 and the hole transport layer 5 that have been transported from the hole transport layer formation step 203 (see FIG. 2) to the light emitting layer formation step 204 (see FIG. 2) are formed. On the hole transport layer 5 of the flexible substrate 3a, the first coating liquid containing the first component host material constituting the light emitting layer in the first coating part 204a (see FIG. 2) is applied. A state where one coating liquid film 6 is formed is shown.

  Step 2 includes a second component dopant material constituting the light emitting layer on the entire surface of the first coating liquid film 6 applied in the second application part 204b (see FIG. 2) of the light emitting layer forming step 204. 2 shows a state in which the second coating liquid is applied and the second coating liquid film 7 is formed. The application of the second coating solution is performed while the mass fraction of the first coating solution film 6 is maintained at 1.0 to 0.1.

  In Step 3, after the second coating liquid film 7 is formed into a film shape, the vibration application is provided after the second wet coating machine 204b1 (see FIG. 2) in the second coating unit 204b (see FIG. 2). By means 204b3 (see FIG. 2), vibration is applied to the first coating liquid film 6 and the second coating liquid film 7, and one coating liquid in which the first coating liquid film 6 and the second coating liquid film 7 are mixed is applied. A state where the liquid film 8 is formed is shown. As a result, the host material and the dopant material are uniformly dispersed without causing intermolecular interactions such as aggregation. Then, the light emitting layer in which the host material and the dopant material are uniformly dispersed is formed by removing the solvent in the drying step.

  A description will be given of the flow shown in FIG.

  Step 1 ′ indicates the same state as Step 1 in FIG.

  Step 2 ′ is a second component constituting a light emitting layer on the entire upper surface of the first coating liquid film 6 applied in the second application part 204b (see FIG. 2) in the light emitting layer forming step 204 (see FIG. 2). The second coating liquid containing the dopant material is applied and the second coating liquid film 7 is formed discretely. The application of the second coating solution is performed while the mass fraction of the first coating solution film 6 is maintained at 1.0 to 0.1.

  Step 3 ′ indicates the same state as Step 3 in FIG.

  Note that the flow shown in FIGS. 4A and 4B includes a first coating solution containing the first component and a second component containing the second component as the coating solution for forming the light emitting layer shown in FIG. The present invention can also be applied to a case where a light emitting layer is formed by coating separately into two coating solutions.

As a typical example of a functional thin film including an organic compound layer composed of at least two components of a first component and a second component on a substrate, an organic EL panel is manufactured by a method as shown in FIGS. The following effects were obtained.
1) By separating the dopant material having different solubility and the host material, the selection range of the solvent used when preparing the coating liquid can be expanded.
2) Preserved coating solution does not cause intermolecular interaction such as agglomeration of dopant material or host material, so it can be applied for a long time and a roll-to-roll system with high production efficiency can be put to practical use. It has become possible.
3) With the light emitting layer in which the dopant material and the host material are uniformly dispersed, an organic EL panel with stable performance can be manufactured.
4) With the production of an organic EL panel with stable performance, it became possible to produce an organic EL lighting device with stable performance.

  Hereinafter, the materials constituting the organic EL panel mentioned as an example of the method for producing the functional thin film of the present invention will be described.

(Band-like flexible substrate)
A resin film is mentioned as a strip | belt-shaped flexible base material. 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, poly Cycloolefin resins such as ether imide, polyether ketone imide, polyamide, fluororesin, nylon, polymethyl methacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Apel (trade name, manufactured by Mitsui Chemicals) Can be mentioned.

(Gas barrier film)
When using a resin film, it is preferable that a gas barrier film is formed on the surface of the resin film as necessary. Examples of the gas barrier film include an inorganic film, an organic film, or a hybrid film of both. As a characteristic of the gas barrier film, it is preferable that the water vapor permeability is 0.01 g / m ² / day or less. Furthermore, it is preferably a high barrier film having an oxygen permeability of 0.1 ml / m ² · day · MPa or less and a water vapor permeability of 10 ⁻⁵ g / m ² / day or less.

  As a material for forming the barrier film, any material may be used as long as it has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like can be used. Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and layers made of organic materials. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times. The method for forming the gas barrier film is not particularly limited. For example, the vacuum deposition method, the sputtering method, the reactive sputtering method, the molecular beam epitaxy method, the cluster ion beam method, the ion plating method, the plasma polymerization method, the atmospheric pressure plasma polymerization method. A plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

(First electrode (anode))
As the first electrode (anode), an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such an electrode substance include metals such as Au, and conductive transparent materials 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. Alternatively, a coatable substance such as an organic conductive compound can be used. For the first electrode (anode), these electrode materials may be formed into a thin film by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or the pattern accuracy is not so required. (About 100 μm or more), a pattern may be formed through a mask having a desired shape when the electrode material is deposited or sputtered. In the case where light emission is extracted from the first electrode (anode), it is desirable that the transmittance be greater than 10%, and the sheet resistance as the first electrode (anode) is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 to 1000 nm, preferably 10 to 200 nm.

(Hole injection layer (anode buffer layer))
A hole injection layer (anode buffer layer) may be present between the first electrode and the light emitting layer or the hole transport layer. The hole injection layer is a layer provided between the electrode and the organic layer for lowering the driving voltage and improving the luminance of light emission. “Organic EL panel and its industrialization front line (NTT, November 30, 1998) The details are described in the second volume, Chapter 2, “Electrode Materials” (pages 123 to 166) of “The Company”. The details of the anode buffer layer (hole injection layer) are described in JP-A Nos. 9-45479, 9-260062, and 8-288069. Specific examples thereof include copper phthalocyanine. Examples thereof include a phthalocyanine buffer layer, an oxide buffer layer typified by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

(Hole transport layer)
The hole transport layer is made of a hole transport material having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers. The hole transport material has any one of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples include stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers.

  The above-mentioned materials can be used as the hole transport material, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound. Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'- Bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ' − (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and also two of those described in US Pat. No. 5,061,569. Having a condensed aromatic ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-3086 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 8 are linked in a starburst type ( MTDATA) and the like.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

  JP-A-11-251067, J. Org. Huang et. al. A so-called p-type hole transport material described in a book (Applied Physics Letters 80 (2002), p. 139) can also be used. These materials are preferably used to obtain a light emitting element with higher efficiency.

  Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. This hole transport layer may have a single layer structure composed of one or more of the above materials. A hole transport layer having a high p property doped with impurities can also be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, JP-A-2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like. It is preferable to use such a hole transport layer having a high p property because an organic EL panel with lower power consumption can be produced.

(Light emitting layer)
The light emitting layer refers to a blue light emitting layer, a green light emitting layer, and a red light emitting layer. There is no restriction | limiting in particular as a lamination order in the case of laminating | stacking a light emitting layer, You may have a nonluminous intermediate | middle layer between each light emitting layer. In the present invention, it is preferable that at least one blue light emitting layer is provided at a position closest to the anode among all the light emitting layers. Also, when four or more light emitting layers are provided, for example, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting layer, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting from the order close to the anode. Layered / green light emitting layer, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting layer / green light emitting layer / red light emitting layer, etc. It is preferable for improving luminance stability. A white element can be manufactured by forming a light emitting layer in multiple layers.

  The light emitting layer includes at least three layers having different emission spectra, each having an emission maximum wavelength in the range of 430 nm to 480 nm, 510 nm to 550 nm, and 600 nm to 640 nm. If it is three or more layers, there will be no restriction | limiting in particular. When there are more than four layers, there may be a plurality of layers having the same emission spectrum. A layer having an emission maximum wavelength in the range of 430 nm to 480 nm is referred to as a blue light emitting layer, a layer in the range of 510 nm to 550 nm is referred to as a green light emitting layer, and a layer in the range of 600 nm to 640 nm is referred to as a red light emitting layer. Moreover, in the range which maintains the said maximum wavelength, you may mix a several luminescent compound in each light emitting layer. For example, a blue light emitting layer may be used by mixing a blue light emitting compound having a maximum wavelength of 430 nm to 480 nm and a green light emitting compound having a maximum wavelength of 510 nm to 550 nm.

  The material used for the light emitting layer is not particularly limited, and examples thereof include the latest trends of Toray Research Center, Inc. flat panel displays, the current state of EL displays and the latest technological trends, and various materials as described on pages 228-332. The light emitting layer preferably contains a known host material and a known dopant material (a phosphorescent compound (also referred to as a phosphorescent compound)) in order to increase the light emission efficiency of the light emitting layer.

  The host material is a material contained in the light emitting layer, the mass ratio in the layer is 20% or more, and the phosphorescence quantum yield of phosphorescence emission is 0.1 at room temperature (25 ° C.). Is defined as less than material. The phosphorescence quantum yield is preferably less than 0.01. A plurality of host materials may be used in combination. By using a plurality of types of host materials, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. In addition, by using a plurality of dopant materials, it is possible to mix different light emission, thereby obtaining an arbitrary emission color. White light emission is possible by adjusting the kind of dopant material and the doping amount, and it can also be applied to illumination and backlight.

(Host material)
As the host material, a material that has a hole transporting ability and an electron transporting ability, prevents the emission of light from becoming longer, and has a high Tg (glass transition temperature) is preferable. Known host materials include, for example, JP-A Nos. 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, and 2002-334786. Gazette, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645 No. 2002-338579, No. 2002-105445, No. 2002-343568, No. 2002-141173, No. 2002-352957, No. 2002-203683, No. 2002-363227, 2002-231453, 2003-3165, 2002-234888, 2003-27048, 2002-255934, 2002-260861, 2002-280183, 2002 -29960, 2002-302516, 2002-305083, 2002-305084, 2002-308837, 2007-59119, 2007-251096, 2007- And compounds described in Japanese Patent No. 250501.

  In the case of having a plurality of light emitting layers, it is preferable that 50% by mass or more of the host compound in each layer is the same compound because it is easy to obtain a uniform film property over the entire organic layer. It is more preferable that the light emission energy is 2.9 eV or more because it is advantageous in efficiently suppressing energy transfer from the dopant material and obtaining high luminance. Phosphorescence emission energy means the peak energy of the 0-0 band of phosphorescence emission when the photoluminescence of a deposited film of 100 nm is measured on a substrate with a host compound.

  The host material has a phosphorescence energy of 2.9 eV or more and a Tg of 90 ° C. or more in consideration of deterioration of the organic EL element over time (decrease in luminance and film properties) and market needs as a light source. Preferably there is. That is, in order to satisfy both luminance and durability, it is preferable that phosphorescence emission energy is 2.9 eV or more and Tg is 90 ° C. or more. Tg is more preferably 100 ° C. or higher.

(Dopant material)
A dopant material (phosphorescent compound (phosphorescent compound)) is a material in which light emission from an excited triplet is observed, and is a material that emits phosphorescence at room temperature (25 ° C.). The rate is a material of 0.01 or more at 25 ° C. When used in combination with the host material described above, an organic EL element with higher luminous efficiency can be obtained.

  The dopant material (phosphorescent compound (phosphorescent compound)) preferably has a phosphorescence quantum yield of 0.1 or more. The phosphorescent quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 version, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence quantum yield used in the present invention only needs to achieve the phosphorescence quantum yield in any solvent.

  There are two types of light emission of the dopant material in principle. One is an energy transfer type in which recombination of carriers occurs on the host material to which carriers are transported to generate an excited state of the host material, and this energy is transferred to the dopant material to obtain light emission from the dopant material. is there. The other is a carrier trap type in which the dopant material becomes a carrier trap, and recombination of carriers occurs on the dopant material, and light emission from the phosphorescent compound is obtained. In any case, the condition is that the excited state energy of the dopant material is lower than the excited state energy of the host material.

  The dopant material can be appropriately selected from known materials used for the light emitting layer of the organic EL element. The dopant material is preferably a complex compound containing a group 8-10 metal in the periodic table of elements, more preferably an iridium compound, an osmium compound, a platinum compound (platinum complex compound), or a rare earth complex. Among them, the most preferable is an iridium compound.

  The maximum phosphorescence wavelength of the dopant material is not particularly limited. In principle, the emission wavelength obtained by selecting a central metal, a ligand, a substituent of the ligand, etc. can be changed. I can do it.

  The color emitted from the material used for the light emitting layer of the organic EL element is shown in FIG. 4.16 on page 108 of the “New Color Science Handbook” (edited by the Japan Color Society, University of Tokyo Press, 1985). -1000 (manufactured by Konica Minolta Sensing Co., Ltd.) is determined by the color when the result of fitting to the CIE chromaticity coordinates.

The white element means that the chromaticity in the CIE1931 color system at 1000 cd / m ² is X = 0.33 ± 0.07, Y = 0.33 ± when the 2 ° C. viewing angle front luminance is measured by the above method. Say that it is in the region of 0.07.

  The light emitting layer formed by drying is a layer that emits light by recombination of electrons and holes injected from the electrode or electron injection layer and hole transport layer, and the light emitting part is within the layer of the light emitting layer. Even the interface between the light emitting layer and the adjacent layer may be used.

(Cathode buffer layer (electron injection layer))
The cathode buffer layer (electron injection layer) is made of a material having a function of transporting electrons and is included in the electron transport layer in a broad sense. The cathode buffer layer (electron injection layer) is a layer provided between the electrode and the organic layer in order to lower the driving voltage and improve the luminance of light emission. “The organic EL panel and the forefront of its industrialization (November 30, 1998) (Issued by TS Co., Ltd.) ”, Chapter 2“ Electrode Materials ”(pages 123 to 166) in the second volume. The details of the cathode buffer layer (electron injection layer) are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. A metal buffer layer typified by lithium fluoride, an alkali metal compound buffer layer typified by lithium fluoride, an alkaline earth metal compound buffer layer typified by magnesium fluoride, an oxide buffer layer typified by aluminum oxide, etc. . The buffer layer (injection layer) is preferably a very thin film, and the film thickness is preferably in the range of 0.1 nm to 5 μm although it depends on the material.

  In addition, as an electron transport material (also serving as a hole blocking material) used for the electron transport layer adjacent to the light emitting layer side, it is sufficient if it has a function of transmitting electrons injected from the cathode to the light emitting layer. As a material, any one of conventionally known compounds can be selected and used. For example, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodisides. Examples include methane and anthrone derivatives, oxadiazole derivatives and the like. Furthermore, in the above oxadiazole derivatives, thiadiazole derivatives in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and quinoxaline derivatives having a quinoxaline ring known as an electron-withdrawing group can also be used as the electron transport material. Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

  In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum Tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), and the like, and the central metals of these metal complexes are In, Mg, Metal complexes replaced with Cu, Ca, Sn, Ga or Pb can also be used as the electron transport material. In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. Distyrylpyrazine derivatives can also be used as electron transport materials, and inorganic semiconductors such as n-type-Si and n-type-SiC are also used as electron transport materials in the same manner as the hole injection layer and hole transport layer. I can do it. Although there is no restriction | limiting in particular about the film thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

  An electron transport layer having a high n property doped with impurities can also be used. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, JP-A-2001-102175, J. Pat. Appl. Phys. 95, 5773 (2004), and the like. It is preferable to use such an electron transport layer having a high n property because an element with lower power consumption can be manufactured.

(Second electrode (cathode))
As the second electrode, a material having a 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 ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like. Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Suitable are a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, a lithium / aluminum mixture, aluminum and the like. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. In order to transmit the emitted light, if either one of the first electrode (anode) or the second electrode (cathode) of the organic EL panel is transparent or translucent, the light emission luminance is improved, which is convenient.

  Moreover, after producing the metal with a thickness of 1 to 20 nm on the second electrode, the conductive transparent material mentioned in the description of the first electrode is produced thereon, so that a transparent or translucent second electrode ( A cathode) can be manufactured, and by applying this, an element in which both the first electrode (anode) and the second electrode (cathode) are transmissive can be manufactured.

(Sealing agent)
Examples of the sealant include a liquid sealant and a thermoplastic resin. As a liquid sealant, acrylic acid oligomers, photocuring and thermosetting sealants having a reactive vinyl group of methacrylic acid oligomers, moisture curable sealants such as 2-cyanoacrylate, etc., Examples thereof include epoxy-based heat- and chemical-curing type (two-component mixed) sealing agents, cationic curing type ultraviolet curing epoxy resin sealing agents, and the like. It is preferable to add a filler to the liquid sealant as necessary. The addition amount of the filler is preferably 5 to 70% by volume in consideration of adhesive strength. Moreover, the magnitude | size of the filler to add considers adhesive strength, the sealing agent thickness after bonding pressure bonding, etc., and 1 micrometer-100 micrometers are preferable. The kind of filler to be added is not particularly limited, and examples thereof include soda glass, non-alkali glass, or silica, titanium dioxide, antimony oxide, titania, alumina, zirconia, tungsten oxide, and other metal oxides.

  As the thermoplastic resin, a thermoplastic resin having a melt flow rate of JIS K 7210 specified in a range of 5 to 20 g / 10 min is preferable, and a thermoplastic resin of 6 to 15 g / 10 min or less is more preferably used. This is because if a resin having a melt flow rate of 5 (g / 10 min) or less is used, the gap caused by the step of the lead electrode of each electrode cannot be completely filled, and a resin of 20 (g / 10 min) or more cannot be filled. This is because if used, the tensile strength, stress cracking resistance, workability and the like are lowered. These thermoplastic resins are preferably formed into a film and bonded to a flexible sealing member (a strip-shaped flexible sealing member or a single-sheet flexible sealing member). The laminating method can be made by using various generally known methods such as a wet laminating method, a dry laminating method, a hot melt laminating method, an extrusion laminating method, and a thermal laminating method.

  The thermoplastic resin is not particularly limited as long as it satisfies the above numerical values. For example, low density polyethylene (LDPE) which is a polymer film described in the new development of functional packaging materials (Toray Research Center, Inc.). ), HDPE, linear low density polyethylene (LLDPE), medium density polyethylene, unstretched polypropylene (CPP), OPP, ONy, PET, cellophane, polyvinyl alcohol (PVA), stretched vinylon (OV), ethylene-vinyl acetate copolymer A combination (EVOH), ethylene-propylene copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, vinylidene chloride (PVDC), or the like can be used. Among these thermoplastic resins, LDPE, LLDPE produced using LDPE, LLDPE and a metallocene catalyst, or a thermoplastic resin using a mixture of LDPE, LLDPE and HDPE films is preferably used.

(Flexible sealing member)
Examples of the flexible sealing member include a material in which a barrier layer is formed on a support made of a flexible resin film such as polyethylene terephthalate or nylon by a vapor deposition method or a coating method, or a material using a metal foil as the barrier layer. Examples of the barrier layer include metals such as In, Sn, Pb, Au, Cu, Ag, Al, Ti, and Ni, MgO, SiO, SiO ₂ , Al ₂ O ₃ , GeO, NiO, CaO, BaO, and Fe ₂ O _3. , Y ₂ O ₃ , TiO _{2, and} other metal oxide vapor deposited materials. Moreover, as a material of the metal foil, for example, a metal material such as aluminum, copper, or nickel, or an alloy material such as stainless steel or an aluminum alloy can be used, but aluminum is preferable in terms of workability and cost. The film thickness is about 1 to 100 μm, preferably about 10 to 50 μm. In order to facilitate handling during production, a film such as polyethylene terephthalate or nylon may be laminated in advance. In the case of using a resin film for the flexible sealing member, it is preferable to have a thermoplastic adhesive resin layer on the side in contact with the liquid sealing agent.

The water vapor permeability of the flexible sealing member is preferably 0.01 g / m ² · day or less, and the oxygen permeability is preferably 0.1 ml / m ² · day · MPa or less. The water vapor permeability is a value measured mainly by the MOCON method by a method based on JIS K7129B method (1992), and the oxygen permeability is a value measured mainly by the MOCON method by a method based on JIS K7126B method (1987). is there. The Young's modulus of the flexible sealing member is 1 × 10 ⁻³ GPa in consideration of adhesion between the flexible sealing member, the first pressure-bonding member and the second pressure-bonding member, prevention of spreading of the sealing agent, and the like. It is -80GPa, and it is preferable that thickness is 10 micrometers-500 micrometers.

  The external extraction efficiency at room temperature of light emission of the organic EL panel produced by the method for producing a functional thin film of the present invention is preferably 1% or more, more preferably 5% or more. Here, the external extraction quantum efficiency (%) = the number of photons emitted to the outside of the organic EL panel / the number of electrons sent to the organic EL panel × 100.

  In addition, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL panel into multiple colors using a phosphor. In the case of using a color conversion filter, the λmax of light emission of the organic EL panel is preferably 480 nm or less.

  The organic EL panel produced by the method for producing a functional thin film of the present invention preferably uses the following method in combination in order to efficiently extract light generated in the light emitting layer. The organic EL panel emits light inside a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1), and only 15% to 20% of the light generated in the light emitting layer can be extracted. It is generally said that there is no. This is because the light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be taken out of the element, or the transparent electrode or light emitting layer and the transparent substrate This is because the light undergoes total reflection between them, the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the direction of the side surface of the device.

  As a method for improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate to prevent total reflection at the interface between the transparent substrate and the air (US Pat. No. 4,774,435). A method for improving efficiency by providing a substrate with a light condensing property (JP-A-63-314795). A method of forming a reflective surface on the side surface of an element (Japanese Patent Laid-Open No. 1-220394). A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between a substrate and a light emitter (Japanese Patent Laid-Open No. 62-172691). A method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter (Japanese Patent Laid-Open No. 2001-202827). There is a method of forming a diffraction grating between any one of the substrate, the transparent electrode layer, and the light emitting layer (including between the substrate and the outside) (Japanese Patent Laid-Open No. 11-283951).

  When an organic EL panel is produced by the method for producing a functional thin film of the present invention, a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitting layer, or a substrate, a transparent electrode layer or a light emitting layer. A method of forming a diffraction grating between any layers (including between the substrate and the outside) can be suitably used.

  When a low refractive index medium is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light extracted from the transparent electrode has a higher extraction efficiency to the outside as the refractive index of the medium is lower. . Examples of the low refractive index layer include aerogel, porous silica, magnesium fluoride, and a fluorine-based polymer. Since the refractive index of the transparent substrate is generally about 1.5 to 1.7, the low refractive index layer preferably has a refractive index of about 1.5 or less. Further, it is preferably 1.35 or less. The thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low refractive index layer is diminished when the thickness of the low refractive index medium is about the wavelength of light and the electromagnetic wave that has exuded by evanescent enters the substrate. The method of introducing a diffraction grating into an interface or any medium that causes total reflection is characterized by a high effect of improving light extraction efficiency. This method uses the property that the diffraction grating can change the direction of light to a specific direction different from refraction by so-called Bragg diffraction such as first-order diffraction or second-order diffraction. Of these, light that cannot be emitted outside due to total internal reflection between layers is diffracted by introducing a diffraction grating in any layer or medium (in a transparent substrate or transparent electrode) It tries to take out light. The introduced diffraction grating desirably has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so in a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction, only light traveling in a specific direction is diffracted. The light extraction efficiency does not increase so much. However, by making the refractive index distribution a two-dimensional distribution, light traveling in all directions is diffracted, and light extraction efficiency is increased.

  As described above, the position where the diffraction grating is introduced may be in any of the layers or in the medium (in the transparent substrate or the transparent electrode), but is preferably in the vicinity of the organic light emitting layer where light is generated. At this time, the period of the diffraction grating is preferably about 1/2 to 3 times the wavelength of light in the medium. The arrangement of the diffraction grating is preferably two-dimensionally repeated, such as a square lattice, a triangular lattice, or a honeycomb lattice.

  Further, in the organic EL panel manufactured by the method for manufacturing a functional thin film of the present invention, in order to efficiently extract light generated in the light emitting layer, a structure on a microlens array, for example, is provided on the light extraction side of the substrate. By processing or combining with a so-called condensing sheet, the luminance in a specific direction can be increased by condensing light in a specific direction, for example, the front direction with respect to the element light emitting surface. As an example of the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably 10 μm to 100 μm. If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

  As the condensing sheet, for example, a sheet that is put into practical use in an LED backlight of a liquid crystal display device can be used. As such a sheet, for example, a brightness enhancement film (BEF) manufactured by Sumitomo 3M Limited can be used. As the shape of the prism sheet, for example, the substrate may be formed with a triangle stripe having a vertex angle of 90 degrees and a pitch of 50 μm, or the vertex angle is rounded, and the pitch is randomly changed. The shape may be other shapes. Moreover, in order to control the light emission angle from a light emitting element, you may use a light-diffusion plate and a film together with a condensing sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

  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.

Example 1
<Preparation of strip-shaped flexible substrate>
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 100 m was prepared. In addition, in order to show the position which forms a 1st electrode previously in the strip | belt-shaped flexible base material, the alignment mark was provided in the same position of the surface in which a 1st electrode is formed, and the opposite surface.

(Formation of the first electrode)
Using the apparatus shown in FIG. 2, a 120 nm thick ITO (Indium Tin Oxide) film is formed on the prepared PET under a vacuum environment condition of 5 × 10 ⁻¹ Pa by a sputtering method, and an extraction electrode is formed. A first electrode having a size of 10 mm × 10 mm having a thickness of 10 mm × 10 mm was continuously formed at regular intervals and temporarily wound up and stored.

(Preparation of coating solution for hole transport layer formation)
A solution prepared by diluting polyethylene dioxythiophene / polystyrene sulfonate (PEDOT / PSS, Baytron P AI 4083 manufactured by Bayer) with pure water at 65% and methanol at 5% was prepared as a coating solution for forming a hole transport layer. The surface tension of the coating liquid for forming a hole transport layer was 40 × 10 ⁻³ N / m (manufactured by Kyowa Interface Chemical Co., Ltd .: surface tension meter CBVP-A3).

(Formation of hole transport layer)
Using the apparatus shown in FIG. 2, wet coating using a coating liquid for forming a hole transport layer is performed on the first electrode of PET on which the first electrode is formed, except for a portion that becomes a take-out electrode. The entire surface was applied so that the thickness after drying was 50 nm by the method. After the formation of the hole transport layer, an antistatic treatment was subsequently performed and the material was transported to the light emitting layer forming step. The conveyance speed was 1 m / min. The charge removal treatment was performed using a static eliminator with weak X-rays. The conveyance speed was measured with a laser Doppler velocimeter LV203 manufactured by Mitsubishi Electric Corporation.

Application conditions The application conditions for the hole transport layer are as follows: the temperature during application of the coating solution for forming the hole transport layer is 25 ° C., an atmospheric pressure of N 2 gas environment with a dew point temperature of −20 ° C. or less, and a cleanliness class 5 The following (JIS B 9920) was performed.

Drying and Heating Treatment Conditions Drying and heating treatment conditions for the hole transport layer include applying a hole transport layer forming coating solution, and then using the drying device and the heat treatment device shown in FIG. After removing the solvent at a height of 100 mm, a discharge wind speed of 1 m / s, a wide wind speed distribution of 5%, and a temperature of 100 ° C. from the discharge port to the film-forming surface, the back surface heat transfer is performed at a temperature of 150 ° C. by a heat treatment device. The hole transport layer was formed by heat treatment of the system.

(Preparation of light emitting layer forming coating solution)
First coating liquid Host material (dicarbazole derivative (CBP)) 1% by mass
Solvent (toluene) 99% by mass
The surface tension of the first coating solution was 28 mN / m at 25 ° C. (manufactured by Kyowa Interface Chemical Co., Ltd .: using surface tension meter CBVP-A3).

Second coating liquid Dopant material (iridium complex (Ir (ppy) ₃ )) 1% by mass
Solvent (toluene) 99% by mass
The surface tension of the second coating solution was 28 mN / m at 25 ° C. (manufactured by Kyowa Interface Chemical Co., Ltd .: surface tension meter CBVP-A3 was used).

(Formation of light emitting layer)
On the PET hole transport layer on which the hole transport layer is formed, the first coating solution is applied at a temperature of 25 ° C. by a wet coating method using an extrusion coating machine, and a wet film thickness equivalent to 5 μm is applied. Then, after forming the first coating liquid having different masses as shown in Table 1, the second coating liquid was subsequently applied in a discrete manner with a wet film thickness of 25 nm by inkjet at a temperature of 25 ° C. A film was formed. Thereafter, vibration is applied to the first coating liquid film and the second coating liquid film by an ultrasonic vibration device under the conditions shown below, the first coating liquid film and the second coating liquid film are mixed, and a solvent is used in the drying unit. And a light emitting layer having a dry film thickness of 50 nm was formed. After forming up to the light emitting layer, antistatic treatment is performed, and after cooling to the same temperature as room temperature, the winding core is formed into a winding roll shape. Temporarily stored as 1-1 to 1-6. The conveying speed was 1 m / min.

As the application conditions of the light emitting layer, the first application liquid and the second application liquid of the application liquid for forming the light emitting layer are applied at 25 ° C. under an atmospheric pressure of N ₂ gas environment having a dew point temperature of −20 ° C. or less, and the cleanliness. It was conducted in class 5 or lower (JIS B 9920).

  In addition, the change of the mass of the 1st coating liquid film was adjusted by arrange | positioning a heating process between the 1st application part of FIG. 2, and the 2nd application part, and heating a 1st coating liquid film.

  The value of mass fraction is a value obtained from a difference in coating film weight before and after passing through the heating step in a preliminary experiment.

  As the vibration applying condition, an ultrasonic oscillator α2 series (manufactured by Chiyoda Electric Co., Ltd.) was used, and vibration was applied under the conditions of a frequency of 35 kHz, an output of 600 W, and a vibration applying time of 30 seconds.

  The drying and heat treatment conditions were as follows: after vibration was applied, the solvent was removed at a discharge wind speed of 1 m / s, a wide wind speed distribution of 0.5 m / s, and a temperature of 60 ° C., followed by heat treatment at a temperature of 150 ° C. A layer was formed.

(Preparation of comparative light emitting layer forming coating solution)
Host material (dicarbazole derivative (CBP)) 1.00% by mass
Dopant material (iridium complex (Ir (ppy) ₃ )) 0.05% by mass
Solvent (toluene) 98.95% by mass
The surface tension of the coating solution was 28 mN / m at 25 ° C. (manufactured by Kyowa Interface Chemical Co., Ltd .: surface tension meter CBVP-A3 was used).

(Formation of comparative light emitting layer)
A coating solution for forming a light emitting layer in which a host material and a dopant material coexist was prepared. The prepared light emitting layer forming coating solution is dried at a temperature of 25 ° C. on the PET hole transport layer formed by the wet coating method using an extrusion coater and up to the hole transport layer of PET. Is applied to a thickness of 50 nm, the solvent is removed at a discharge wind speed of 1 m / s, a wide wind speed distribution of 0.5 m / s, and a temperature of 60 ° C., followed by heat treatment at a temperature of 150 ° C. No. 1-7. As the light emitting layer coating conditions, the light emitting layer forming coating solution is applied at 25 ° C. under an atmospheric pressure of N ₂ gas environment with a dew point temperature of −20 ° C. or lower, and a cleanliness class 5 or lower (JIS B 9920). It was.

(Formation of cathode buffer layer (electron injection layer))
Subsequently, Sample No. in which up to the prepared light emitting layer was formed. 1-1F is used as the cathode buffer layer (electron injection layer) layer forming material on the entire upper surface of the light emitting layers 1-1 to 1-7 under a vacuum environment condition of 5 × 10 ⁻⁴ Pa. A LiF layer (electron injection layer) having a thickness of 0.5 nm was laminated by a vapor deposition method except for the portion to be.

(Formation of second electrode)
Subsequently, on the entire upper surface of the formed electron injecting layer, aluminum was used as the second electrode forming material under a vacuum of 5 × 10 ⁻⁴ Pa, and a mask pattern was formed by vapor deposition so as to have a takeout electrode, A second electrode having a thickness of 100 nm was laminated to produce an organic EL element.

(Production of organic EL panel)
(Applying adhesive)
An ultraviolet curable liquid adhesive (epoxy resin system) is used around the light emitting region and the light emitting region except for the end portions of the first electrode and the second electrode leading electrode of the produced organic EL element, and the thickness is 30 μm. Painted.

(Pasting of sealing member)
Thereafter, the belt-like sheet sealing member shown below was prepared by stacking on the adhesive-coated surface of the organic EL element by a roll laminator method, and after roll-bonding at a pressure of 0.1 MPa in an atmospheric pressure environment, a wavelength of 365 nm The high pressure mercury lamp 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 a plurality of organic EL panels were continuously connected.

(Preparation of strip-shaped sheet sealing member)
A two-layer belt-like sheet sealing member using a PET film (manufactured by Teijin DuPont) as the sealing member and using an inorganic film (SiN) as a barrier layer was prepared. The thickness of PET was 100 μm, and the thickness of the barrier layer was 200 nm. Incidentally, the barrier layer of the PET film was formed by a sputtering method. The water vapor permeability measured by the MOCON method by a method based on the JIS K-7129B method (1992) was 0.01 g / m ² · day. The oxygen permeability measured mainly by the MOCON method by a method based on JIS K7126B method (1987) was 0.1 ml / m ² · day · MPa.

(Cutting)
A sample in which a plurality of prepared organic EL panels are continuously connected is cut according to the size of the individual organic EL panel, and the sample No. 101-107.

Evaluation Each sample No. Samples are taken from the first 5 m and the last 5 m on 101 to 107, and leakage current characteristics and dark spots (spot-shaped non-light emitting parts) are tested by the following test methods, according to the evaluation ranks shown below. The evaluation results are shown in Table 2.

Test Method for Leakage Current Characteristics Using a constant voltage power source, a reverse voltage (reverse bias) was applied at 5 V for 5 seconds, and the current flowing through the organic EL element at that time was measured. Measurement was performed on the light emission region of 10 samples, and the maximum current value was defined as a leakage current.

Evaluation rank of leakage current characteristics A: Maximum current value is less than 1 × 10 ⁻⁶ A ○: Maximum current value is 1 × 10 ⁻⁶ A or more and less than 1 × 10 ⁻⁵ A Δ: Maximum current value is 1 × 10 ^{− 5} A or more, less than 1 × 10 ⁻³ A ×: Maximum current value is 1 × 10 ⁻³ A or more Measurement method for the number of dark spots (spot-shaped non-light emitting parts) Organic EL panel using constant voltage power A direct current of 5V was applied thereto, 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 spot (spot-like non-light emitting portion) A: No occurrence of dark spot.

○: 1 or more dark spots, less than 5 △: 5 or more dark spots, less than 20 x: 20 or more dark spots

  Organic EL panel No. 101-105 apply | coat a 2nd coating liquid and form a 2nd coating liquid film, while the mass fraction of a 1st coating liquid film hold | maintains 1.0-0.1, and it vibrates by a vibration provision means. It was confirmed that a stable organic EL panel with good leakage current characteristics and a small number of dark spots was manufactured because the first coating liquid film and the second coating liquid film were uniformly mixed. .

  Organic EL panel No. No. 106 applied the second coating liquid in a state where the mass fraction of the first coating liquid film was 0.05 to form a second coating liquid film, and applied vibration by the vibration applying means. It was confirmed that an unstable organic EL panel with poor leakage current characteristics and a large number of dark spots was produced due to non-uniform mixing with the two coating liquid films.

  Organic EL panel No. No. 107 used a light emitting layer forming coating solution in which a host material and a dopant material coexisted, so there was no problem at the beginning, but at the end, intermolecular interactions such as aggregation occurred, leakage current characteristics were poor, dark spots It was confirmed that an unstable and organic EL panel was produced. The effectiveness of the present invention was confirmed.

Example 2
(Preparation of base material)
50 sheets of soda-lime glass having a thickness of 1.1 mm, a width of 40 mm, and a length of 60 mm were prepared as substrates. In addition, the surface of the soda-lime glass used was a silica-coated glass for protection from acid and alkali.

(Formation of the first electrode)
After patterning on a base material (NA Techno-Glass NA-45) in which ITO (Indium Tin Oxide) is deposited to 100 nm on 50 glass base materials prepared as the first electrode, this ITO transparent electrode is provided. The transparent substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

(Preparation of coating solution for hole transport layer formation)
1.2. A hole transport layer forming coating solution by dissolving 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD) as a hole transport material so as to be 1% by mass in dichloroethane. It was.

(Formation of hole transport layer)
Using the apparatus shown in FIG. 3, on the first electrode formed on the prepared glass substrate, the prepared hole transport layer forming coating solution was applied using a slit coater, and then the temperature was 80 ° C. Then, drying and heat treatment were performed under the conditions for 60 minutes to provide a hole transport layer having a thickness of 40 nm.

(Preparation of light emitting layer forming coating solution)
First coating liquid Host material (polyvinylcarbazole) 1% by mass
Solvent (anisole) 99% by mass
The surface tension of the first coating liquid was 36 mN / m at 25 ° C. (manufactured by Kyowa Interface Chemical Co., Ltd .: surface tension meter CBVP-A3 was used).

Second coating liquid Dopant material (iridium complex (Ir (ppy) ₃ )) 1% by mass
Solvent (anisole) 99% by mass
The surface tension of the second coating solution was 36 mN / m at 25 ° C. (manufactured by Kyowa Interface Chemical Co., Ltd .: using a surface tension meter CBVP-A3).

(Formation of light emitting layer)
On the hole transport layer of the glass substrate on which the hole transport layer is formed, the prepared first coating liquid is equivalent to 5 μm in a wet film thickness by a wet coating method using a spray coating machine at a temperature of 25 ° C. After forming the first coating liquid film having a different mass as shown in Table 3, the second coating liquid was applied in a discrete manner by an ink jet at a temperature of 25 ° C. and a wet film thickness equivalent to 25 nm was applied. Two coating liquid films were formed. Thereafter, vibration is applied to the first coating liquid film and the second coating liquid film by an ultrasonic vibration device under the conditions shown below, the first coating liquid film and the second coating liquid film are mixed, and a solvent is used in the drying unit. And a heat treatment was performed to form a light emitting layer having a dry film thickness of 50 nm, followed by cooling to the same temperature as room temperature. Temporarily stored as 2-1 to 2-6.

  The first coating solution and the second coating solution were applied at a dew point temperature of −20 ° C. or lower and a cleanliness class 5 or lower (JIS B 9920) in an atmospheric environment of 25 ° C.

  In addition, the change of the volume (solvent amount) of the first coating liquid film is adjusted by arranging a heating step between the first coating part and the second coating part in FIG. 3 and heating the first coating liquid film. did.

  The value of mass fraction is a value obtained from a difference in coating film weight before and after passing through the heating step in a preliminary experiment.

  As the vibration applying condition, an ultrasonic oscillator α2 series (manufactured by Chiyoda Electric Co., Ltd.) was used, and vibration was applied under the conditions of a frequency of 25 kHz, an output of 400 W, and a vibration applying time of 30 seconds.

  The drying and heat treatment conditions were as follows: after vibration was applied, the solvent was removed at a discharge wind speed of 1 m / s, a wide wind speed distribution of 0.5 m / s, and a temperature of 60 ° C., followed by heat treatment at a temperature of 150 ° C. to emit light. A layer was formed.

(Preparation of comparative light emitting layer forming coating solution)
Host material (polyvinylcarbazole) 1.00% by mass
Dopant material (iridium complex (Ir (ppy) ₃ )) 0.05% by mass
Solvent (toluene) 98.95% by mass
The surface tension of the coating solution was 36 mN / m at 25 ° C. (manufactured by Kyowa Interface Chemical Co., Ltd .: surface tension meter CBVP-A3 was used).

(Formation of comparative light emitting layer)
A coating solution for forming a light emitting layer in which a host material and a dopant material coexist was prepared. The prepared light-emitting layer forming coating solution is dried in a film form on the hole transport layer of the glass substrate on which the prepared hole transport layer is formed by a wet coating method using a spray coater at a temperature of 25 ° C. The film was applied to a film thickness of 50 nm, the solvent was removed at a discharge wind speed of 1 m / s, a wide wind speed distribution of 0.5 m / s, and a temperature of 60 ° C., followed by heat treatment at a temperature of 150 ° C. A light emitting layer is formed and no. 2-7.

(Formation of electron transport layer)
An LiF layer having a thickness of 0.5 nm was deposited on the formed light emitting layer under a vacuum of 5 × 10 ⁻⁴ Pa to form an electron transport layer.

(Formation of second electrode)
On the formed electron transport layer, an aluminum layer having a thickness of 100 nm was deposited under a vacuum of 5 × 10 ⁻⁴ Pa, and an electrode was laminated to produce an organic EL device.

(Production of organic EL panel)
(Formation of sealing layer)
On the formed electron transport layer, a polyethylene terephthalate as a substrate, using a flexible sealing member which is deposited to a thickness 300nm of Al ₂ O _3. Apply the adhesive around the second electrode except for the end so that the external lead terminals of the first electrode and the second electrode can be formed, paste the flexible sealing member, and then cure the adhesive by heat treatment It was. Thereafter, unnecessary portions of the flexible sealing member are removed by punching and cutting to form a sealing layer to obtain an organic EL panel. 201-207.

(Evaluation)
Each prepared sample No. From 201 to 207, the first five samples and the last five samples are extracted, and leakage current characteristics and the number of dark spots are tested by the same test method as in Example 1, and evaluated according to the same evaluation rank as in Example 1. Table 4 shows the results.

  Organic EL panel No. 201-205 apply | coat a 2nd coating liquid and form a 2nd coating liquid film, while a 1st coating liquid film hold | maintains mass fraction 1.0-0.1, and it vibrates by a vibration provision means. As a result of the addition, the first coating liquid film and the second coating liquid film were uniformly mixed, and it was confirmed that a stable organic EL panel having good leakage current characteristics and a small number of dark spots was manufactured.

  Organic EL panel No. 206 is the first coating liquid film formed by applying the second coating liquid in a state where the mass fraction of the first coating liquid film is 0.05 to form a second coating liquid film and applying vibration by the vibration applying means. Since the mixing with the second coating liquid film became non-uniform, it was confirmed that an unstable organic EL panel having good leakage current characteristics and a large number of dark spots was manufactured.

  Organic EL panel No. Since 207 used a coating solution for forming a light emitting layer in which a host material and a dopant material coexisted, there was no problem at the beginning, but at the end, intermolecular interactions such as agglomeration occurred, leakage current characteristics were poor, dark spots It was confirmed that an unstable and organic EL panel was produced. The effectiveness of the present invention was confirmed.

Example 3
<Preparation of strip-shaped flexible substrate>
The same belt-like flexible substrate as in Example 1 was prepared.

(Formation of the first electrode)
Using the apparatus shown in FIG. 2, the first electrode was formed on the prepared strip-shaped flexible substrate under the same conditions and in the same manner as in Example 1.

(Formation of hole transport layer)
Using the apparatus shown in FIG. 2, a hole transport layer was formed on the formed first electrode under the same conditions and in the same manner as in Example 1.

(Preparation of light emitting layer forming coating solution)
Preparation of the first coating solution As shown in Table 5, a first coating solution was prepared using a solvent in which the boiling point of the solvent used for the preparation of the first coating solution was changed. a to f.
Preparation of first coating liquid Host material (dicarbazole derivative (CBP)) 1% by mass
Solvent (ad) 99% by mass

(Preparation of second coating solution)
As shown in Table 6, a second coating solution was prepared using a solvent in which the boiling point of the solvent used for the preparation of the second coating solution was changed. I decided to

Preparation of second coating solution Dopant material (iridium complex (Ir (ppy) ₃ )) 1% by mass
Solvent (i-ho) 99% by mass

(Formation of light emitting layer)
On the formed hole transport layer, as shown in Table 7, the first coating solution No. 1 shown in Table 5 was used. a to f and the second coating solution No. shown in Table 6. It was applied by a wet application method in combination with (i) to (f). Thereafter, vibration is applied to the first coating liquid film and the second coating liquid film by an ultrasonic vibration device under the conditions shown below, the first coating liquid film and the second coating liquid film are mixed, and a solvent is used in the drying unit. And a light emitting layer having a dry film thickness of 50 nm was formed. After forming up to the light emitting layer, antistatic treatment is performed, and after cooling to the same temperature as room temperature, the winding core is formed into a winding roll shape. Temporarily stored as 3-1 to 3-36. The conveying speed was 1 m / min.

Application conditions of the first coating liquid A wet coating thickness of 5 μm was applied in a film form by a wet coating method using an extrusion coating machine at a temperature of 25 ° C. to form a first coating liquid film.

Application conditions of the second coating liquid After the first coating liquid film is formed, the second coating liquid is continuously (in a state where the residual solvent is 100%), and the second coating liquid is discretely formed by ink jet at a temperature of 25 ° C. This was applied to form a second coating liquid film.

(Vibration condition)
As the vibration applying condition, an ultrasonic oscillator α2 series (manufactured by Chiyoda Electric Co., Ltd.) was used, and vibration was applied under the conditions of a frequency of 25 kHz, an output of 400 W, and a vibration applying time of 30 seconds.

  The drying and heat treatment conditions were as follows: after vibration was applied, the solvent was removed at a discharge wind speed of 1 m / s, a wide wind speed distribution of 0.5 m / s, and a temperature of 60 ° C., followed by heat treatment at a temperature of 150 ° C. A layer was formed.

(Formation of cathode buffer layer (electron injection layer))
Subsequently, Sample No. in which up to the prepared light emitting layer was formed. A LiF layer (electron injection layer) having a thickness of 0.5 nm was stacked on the entire upper surface of the light emitting layers 3-1 to 3-36 using LiF under the same conditions as in Example 1.

(Formation of second electrode)
Subsequently, aluminum was used on the entire surface of the electron injection layer under the same conditions as in Example 1, a mask pattern was formed by vapor deposition so as to have a takeout electrode, and a second electrode having a thickness of 100 nm was laminated to form an organic EL element. Was made.

(Production of organic EL panel)
An ultraviolet curable liquid adhesive (epoxy resin system) is used around the light emitting region and the light emitting region except for the end portions of the first electrode and the second electrode leading electrode of the produced organic EL element, and the thickness is 30 μm. Painted.

(Preparation of sealing member)
A two-layer belt-like sheet sealing member using a PET film (manufactured by Teijin DuPont) as the sealing member and using an inorganic film (SiN) as a barrier layer was prepared. The thickness of PET was 100 μm, and the thickness of the barrier layer was 200 nm. Incidentally, the barrier layer of the PET film was formed by a sputtering method. The water vapor permeability measured by the MOCON method by a method based on the JIS K-7129B method (1992) was 0.01 g / m ² · day. The oxygen permeability measured mainly by the MOCON method by a method based on JIS K7126B method (1987) was 0.1 ml / m ² · day · MPa.

(Cutting)
A sample in which a plurality of prepared organic EL panels are continuously connected is cut according to the size of the individual organic EL panel, and the sample No. 301 to 336.
Evaluation Each sample No. 301 to 336, samples are extracted from the first 5 m and the last 5 m, and leakage current characteristics and dark spots (spot-shaped non-light emitting portions) are tested by the same test method as in Example 1. The results of evaluation according to the same evaluation rank as 1 are shown in Table 8.

  Sample No. 1 was prepared using a solvent having a boiling point of 61.3 ° C. used for the first coating solution and a solvent compatible with the solvent having the changed boiling point. In any of 301 to 305, the drying of the first coating film is accelerated, so that the mixed state with the second coating film is not stable, the leakage current characteristics are not stable, the number of dark spots is slightly increased, and the stability is increased. It was confirmed that an inferior organic EL panel was manufactured.

  Use a solvent having a boiling point in the range of 80 ° C. to 210 ° C. for the solvent used for the first coating solution and a solvent compatible with the solvent for which the boiling point is changed for the solvent used for the second coating solution. The prepared sample No. It was confirmed that 307 to 311, 313 to 317, 319 to 323, 325 to 329, and 331 to 335 were all manufactured with a stable organic EL panel having good leakage current characteristics and a small number of dark spots. In addition, Sample No. 2 was prepared with the boiling point of the solvent used for the second coating solution being as high as 215 ° C. 312, 318, 324, 330, and 336 produce a stable organic EL panel with good leakage current characteristics and a small number of dark spots, but it took time to dry.

Sample No. 1 was prepared by using a solvent having a boiling point of 215 ° C. used for the first coating liquid and a solvent compatible with the solvent whose boiling point was changed as the solvent used for the second coating liquid. Nos. 331 to 335 produce stable organic EL panels with good leakage current characteristics and a small number of dark spots, but the results required time for drying.
The effectiveness of the present invention was confirmed.

It is the schematic which shows an example of the organic electroluminescent panel used for illumination. It is a schematic diagram which shows an example of the manufacturing process which manufactures the organic electroluminescent panel shown in FIG. 1 using a strip | belt-shaped flexible base material. It is a schematic diagram which shows an example of the manufacturing process which manufactures the organic EL panel shown in FIG. 1 using a sheet-fed base material. It is a schematic diagram which shows the flow until the 2nd coating liquid film apply | coated on the 1st coating liquid film in the light emitting layer formation process shown by FIG. 2 is mixed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic electroluminescent panel 101 Flexible base material 102 Anode (1st electrode)
103 hole transport layer 104 light emitting layer 105 cathode buffer layer (electron injection layer)
106 Cathode (second electrode)
107 Adhesive layer 108 Sealing member 2, 4 Manufacturing process 201, 401 Supply process 202 First electrode forming process 203, 402 Hole transport layer forming process 204, 403 Light emitting layer forming process 204a, 403a First coating part 204a3, 403a1 First wet coater 204b, 403b Second coater 204b1, 403b1 Second wet coater 204b3, 403b4 Vibration applying means 204c, 403c Dryer 205, 404 Cathode buffer layer (electron injection layer) forming process 206, 405 Second electrode Formation process 207, 406 Sealing process 208, 407 Cutting process 3, 3a, 5 Base material

Claims (9)

In the method for producing a functional thin film having an organic compound layer having at least a first component and a second component on a substrate,
The organic compound layer is formed by applying the first coating liquid on the substrate to form a first coating liquid film,
Applying a second coating liquid containing the second component on the first coating liquid film while the mass fraction of the first coating liquid film is maintained at 1.0 to 0.1; and A method for producing a functional thin film, which is formed by applying vibration and drying. The functional thin film is a functional thin film having at least two layers on a substrate, and at least one of the two layers has an organic compound layer having a first component and a second component;
The organic compound layer is formed by applying a first coating liquid containing the first component on the substrate to form a first coating liquid film,
Applying a second coating liquid containing the second component on the first coating liquid film while the mass fraction of the first coating liquid film is maintained at 1.0 to 0.1; and The method for producing a functional thin film according to claim 1, wherein the functional thin film is formed by applying vibration and drying. An organic electroluminescence panel in which the functional thin film sequentially includes at least a first electrode, an organic compound layer having at least two components of a first component and a second component, a second electrode, and a sealing layer on a substrate. The organic compound layer of
The organic compound layer is formed by applying a first coating liquid containing the first component on the first electrode to form a first coating liquid film.
Applying a second coating liquid containing the second component on the first coating liquid layer while maintaining a mass fraction of the first coating liquid film of 1.0 to 0.1; and It forms by adding vibration and drying, The manufacturing method of the functional thin film of Claim 2 characterized by the above-mentioned. The method for producing a functional thin film according to claim 1, wherein the application of the second coating liquid is performed by a droplet coating method. The method for producing a functional thin film according to any one of claims 1 to 4, wherein the solvent used in the first coating solution has a boiling point of 80C to 210C. The method for producing a functional thin film according to claim 3, wherein the organic compound layer is a light emitting layer having at least a host material and a dopant material. The method for producing a functional thin film according to any one of claims 3 to 6, wherein the first component is a host material, and the second component is a dopant material. The method for producing a functional thin film according to any one of claims 1 to 7, wherein the substrate is a belt-like flexible substrate. An organic electroluminescence lighting device using the organic electroluminescence panel produced by the method for producing a functional thin film according to any one of claims 3 to 8.

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