JP5092756B2 - Organic electroluminescent panel manufacturing method, organic electroluminescent lighting device, and organic electroluminescent panel manufacturing device - Google Patents

Description

The present invention relates to a method for manufacturing an organic electroluminescence panel (hereinafter also referred to as an organic EL panel) manufactured by a roll-to-roll method, an organic electroluminescence lighting device, and an apparatus for manufacturing an organic electroluminescence panel .

  In recent years, use of an organic electroluminescence (EL) element as a light source for a display device such as a flat display, an electrophotographic copying machine, or a printer 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, an organic layer made of a hole transport layer and a light emitting layer, and an anode A cathode made of aluminum or the like, which is formed in a crossed pattern in a crossing manner, is provided in this order, and an anode and a cathode are provided at the periphery of the pixel portion where the organic EL elements are arranged in a matrix. An anode-side extraction electrode and a cathode-side extraction electrode for connection to an external circuit or an internal drive circuit are formed.

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

  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 substance is an insulator, but by making the thickness of the organic layer very thin, current can be injected and it can be driven as an organic EL element. 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 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)) up to a luminous efficiency as high as 60 lm / W, such an element is used not only for a display but also for an illumination. Application to is expected.

  As a method for forming a very thin thin film of a fluorescent organic compound used for an organic EL element, 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 a coating solution is prepared to form 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.

As a method for producing an organic EL element, a single-wafer method using a single-wafer substrate and a roll-to-roll method using a strip-shaped flexible substrate are known. However, single whereas leaf method is limited to raise the production efficiency, the roll-to-roll method study of how production efficiency in combination with a wet process method it is highly likely that above has been developed .

  When an organic functional layer such as a hole transport layer or a light emitting layer constituting an organic EL element is applied by a wet process method, if an organic functional layer is formed on the entire surface of the substrate, it is patterned and formed in advance on the substrate. The film is also formed on the portion of the anode that becomes the external electrode extraction portion.

Since the organic layer is basically an insulator, if there is an organic functional layer at the electrical contact, conduction failure will occur. For this reason, a method in which the organic functional layer is not formed in the portion serving as the external electrode extraction portion has been studied so far.

  For example, after forming a liquid-repellent part between the light-emitting part and the non-light-emitting part, an organic layer is formed by a coating method, and the organic layer formed on the non-light-emitting part outside the liquid-repellent part is wiped off with a solvent. A method of manufacturing an organic EL display device is known (see, for example, Patent Document 1).

However, Patent Document 1 does not describe any roll-to-roll method using a strip-shaped flexible substrate as a substrate, and when the method described in Patent Document 1 is applied to a roll-to-roll method, It has been found that it has certain disadvantages.
1) The liquid repellent part must be formed in all the parts forming the light emitting part, and when a plurality of organic EL elements are formed on a strip-like flexible substrate, the production efficiency is extremely lowered.
2) The unnecessary organic layer may be wiped away with a solvent. However, when a plurality of organic EL elements are formed on a strip-shaped flexible substrate, the unnecessary organic layer is uniformly attached to all the organic EL elements. Removal is considered difficult and there is a risk of variations in performance.

  Further, after forming a plurality of anodes on the transparent substrate, an organic material layer including an organic luminescence layer is formed on the entire anode. After this, the organic material on the external extraction portion is removed, and a solvent that dissolves the organic material layer is applied to unnecessary portions of the organic material layer in order to form an organic material layer that matches the plurality of formed anode regions. Then, a method of removing it is known (for example, see Patent Document 2).

However, Patent Document 2 does not describe any roll-to-roll method using a strip-shaped flexible substrate as a substrate, and when the method described in Patent Document 2 is applied to the roll-to-roll method, It has been found that it has certain disadvantages.
1) Since the fluid in which the organic material layer dissolves is sprayed on unnecessary portions of the organic material layer, the sprayed fluid droplets adhere to the necessary portions of the organic material layer, so that the organic material layer melts and the film thickness becomes uneven. There is a risk of variations in performance.
2) If the fluid sprayed onto the organic material layer is not scattered, the application speed of the fluid is slowed and the production efficiency is lowered.
3) If the sprayed fluid is not completely removed, the organic material layer that is originally required is dissolved to cause variation in the light emitting region, so that it takes time to remove the fluid and the production efficiency decreases.
4) Especially when the substrate is a flexible support having a wide band shape and a plurality of organic EL elements are continuously produced, it takes time to uniformly remove the organic layer, and the production efficiency is lowered.

  A plurality of first electrodes are formed on a strip-shaped flexible substrate by a roll-to-roll method, and a hole transport layer forming coating solution and a light emitting layer are formed on these first electrodes by a wet coating method. A method is known in which a coating solution is sequentially applied in a pattern to form a hole transport layer and a light emitting layer (see, for example, Patent Document 3).

However, the method described in Patent Document 3 has the following drawbacks.
1) Since a hole transport layer and a light emitting layer are sequentially laminated on a plurality of first electrodes formed on a strip-shaped flexible substrate by pattern coating, it takes time to coat and further production efficiency Is difficult to raise.
2) When pattern coating is performed, the coating film becomes discontinuous, so that each coating region has a coating edge. As a result, the flow of the coating liquid is caused by the difference in the evaporation rate due to the difference in the solvent vapor concentration at the center and the end of each coating region, thereby inducing non-uniform film thickness called drying unevenness.

From such a situation, an organic EL panel having at least a first electrode, one or more organic functional layers, a second electrode, and a sealing layer on a strip-shaped flexible substrate is formed into a roll-to-roll method. Therefore, there is a demand for the development of an organic EL panel manufacturing method and an organic EL display device that have high production efficiency and stable performance quality.
JP 2004-152512 A JP 2003-31364 A International Publication No. 06/100889 Brochure

The present invention has been made in view of the above circumstances, and the object thereof is to provide at least a first electrode, one or more organic functional layers, a second electrode, and a sealing layer on a strip-shaped flexible substrate. It is to provide an organic EL panel manufacturing method , an organic EL lighting device, and an organic EL panel manufacturing apparatus that have high production efficiency and stable performance quality by a roll-to-roll method.

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

1. A roll-to-roll organic electroluminescence panel comprising a first electrode, at least one organic functional layer, a second electrode, and a sealing layer on a continuous flexible resin film that is transported continuously in the manufacturing method of the organic electroluminescent panel manufactured by a method, after the application of the organic functional layer coating solution by a wet coating method on the entire surface of the front Symbol first electrode and dried to form the organic functional layer, A good solvent that dissolves the organic functional layer is applied to the unnecessary area of the organic functional layer by pattern coating, the unnecessary area is dissolved in the good solvent, and the unnecessary solvent is not used by dissolving the unnecessary organic solvent. by region handles the dissolved good solvent removed, producing side of the organic electroluminescent panel, characterized in that formed by patterning the organic functional layer at least one layer .

2. The pattern coating method of manufacturing an organic electroluminescent panel according to above, wherein the Rukoto performed by a droplet discharge method.

  3. 3. The method for producing an organic electroluminescence panel according to 1 or 2, wherein the treatment with the poor solvent is a rinsing method or an immersion method.

4). 4. An organic electroluminescence lighting device using the organic electroluminescence element produced by the method for producing an organic electroluminescence panel according to any one of 1 to 3.
5. A roll-to-roll organic electroluminescence panel comprising a first electrode, at least one organic functional layer, a second electrode, and a sealing layer on a continuous flexible resin film that is transported continuously In an organic electroluminescence panel manufacturing apparatus manufactured by a method, a coating means for applying a coating liquid for forming an organic functional layer by a wet coating method on the entire surface of the first electrode, and a coating liquid for forming the organic functional layer are dried. A drying means for forming the organic functional layer, a pattern coating means for pattern-coating a good solvent for dissolving the organic functional layer in an unnecessary area of the organic functional layer, and a poor solvent for not dissolving the organic functional layer. And a solvent removing means for treating and removing the good solvent in which the unnecessary region is dissolved.
6). 6. The organic electroluminescence panel manufacturing apparatus as described in 5 above, wherein the pattern coating means is means using a droplet discharge method.
7). 7. The organic electroluminescence panel manufacturing apparatus according to 5 or 6, wherein the solvent removing means is a means using a rinsing method or an immersion method.

An organic EL panel having at least a first electrode, one or more organic compound layers, a second electrode, and a sealing layer on a strip-shaped flexible substrate has high production efficiency by a roll-to-roll method, An organic EL panel manufacturing method , an organic EL lighting device, and an organic EL panel manufacturing device with stable performance quality can be provided.

  Embodiments of the present invention will be described with reference to FIGS. 1 to 7, but the present invention is not limited thereto.

  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, an electron transport layer 105, and a cathode buffer layer (electron injection layer) sequentially on a flexible substrate 101. ) 106, a cathode (second electrode) 107, an adhesive layer 108, and a sealing member 109. A sealing layer is formed by the adhesive layer 108 and the sealing member 109. The organic EL panel 1 has an adhesion sealing structure that is sealed by an adhesive layer 108 except for an end portion of the extraction electrode 102a of the anode (first electrode) 102 and the extraction electrode 107a of the cathode (second electrode) 107. 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 in which the second electrode is sealed with the sealing member 109 is referred to as an organic EL panel, and the state in which up to the second electrode is formed is referred to as an organic EL element.

  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) / light emitting layer / cathode (second electrode)
(2) Anode (first electrode) / light emitting layer / electron transport layer / cathode (second electrode)
(3) Anode (first electrode) / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode (second electrode)
(4) Anode (first electrode) / hole transport layer (hole injection layer) / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer (electron injection layer) / cathode (second electrode)
(5) Anode (first electrode) / anode buffer layer (hole injection layer) / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer (electron injection layer) / cathode (second electrode)
Each layer constituting the organic EL panel will be described later.

  FIG. 2 is a schematic view showing an example of a production process for producing the organic EL panel shown in FIG. 1 by a roll-to-roll method using a belt-like flexible substrate.

  In the figure, reference numeral 2 denotes a manufacturing process of the organic EL panel. The 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, an electron transport layer forming process 205, It has a cathode buffer layer (electron injection layer) forming step 206, a second electrode forming step 207, a sealing step 208, and a recovery step 209. In addition, as the collection step 209, a cutting device for obtaining individual organic EL panels from a strip-like flexible base material having a plurality of organic EL panels may be used, or a strip-like one having a plurality of organic EL panels may be used. You may use the winding apparatus which winds up a flexible base material in roll shape. When a winding device is used, after being wound up and collected in a roll shape, a plurality of organic EL panels produced on a band-shaped flexible substrate in another process are cut into individual organic EL panels. It doesn't matter.

  The roll-to-roll is a method for producing an organic EL panel through a first electrode forming step 202 to a sealing step 208 in order using a strip-like flexible base material wound in a roll shape as shown in the figure. Say.

  In addition, although this figure has shown the case where the supply process 201-collection | recovery process 209 is continued, when the whole process becomes long and installation becomes difficult, a process will be divided | segmented suitably and a strip | belt-shaped flexible base material will be rolled. The belt-shaped flexible substrate may be supplied in the form of a roll to the next process again. Each step will be described with reference to FIGS.

  FIG. 3 is a schematic diagram up to the supplying step shown in FIG. 2 and the first electrode forming step.

In the figure, 201 shows a supply process of the strip-shaped flexible substrate 3, and 202 shows a first electrode formation process. From supplying step 201, continuously uses a feeding device for feeding a roll of flexible substrate 301 (not shown), a band-like flexible base material 3 to the first electrode forming step 202 follows step It feeds 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 uses a first electrode forming device 202a, a first accumulator 202b, a second accumulator 202c, and a winding device 202d. The first electrode forming apparatus 202a includes a vapor deposition apparatus 202a1 having an evaporation source container 202a2.

  The first accumulator 202b has a plurality of lower conveyance rollers 202b1 and a plurality of upper conveyance rollers 202b2, and is arranged for speed adjustment with the supply step 201. The second accumulator 202c has a plurality of lower conveyance rollers 202c1 and a plurality of upper conveyance rollers 202c2, and is arranged for speed adjustment by the winding device 202d.

  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 first electrode forming apparatus 202a in accordance with information (not shown). The number of first electrodes to be formed can be appropriately determined from the width of the strip-shaped flexible substrate, the size of the organic EL panel to be manufactured, and the like. The thickness of the first electrode is preferably 100 nm to 200 nm. After the first electrode is formed, it is preferable that the belt-shaped flexible base material in which the first electrode is laminated through the conveying roller 202d1 is temporarily wound and temporarily stored by the winding device 202d. After the primary storage, it is sent to the hole transport layer forming step 203 (see FIG. 4). In addition, when not winding up and storing, it is continuously sent to the hole transport layer forming step 203 (see FIG. 2).

  The supply process 201 and the first electrode positive formation process 202 are preferably performed 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.

  FIG. 4 is a schematic diagram of the hole transport layer forming step shown in FIG.

  The hole transport layer forming step 203 includes a feeding unit 203a, a coating unit 203b, a drying unit 203c, a pattern forming unit 203d, and a winding unit 203e. In the hole transport layer forming step 203, a hole transport layer forming coating solution is applied to the entire upper surface of the first electrode of the strip-shaped flexible substrate 3 formed up to the first electrode, and passes through the drying section 203c. After forming a hole transport layer (not shown, corresponding to the hole transport layer 103 in FIG. 1), the pattern forming unit 203d transports holes around the first electrode take-out electrode forming unit and the adjacent first electrode. The layer is removed and patterning is performed according to the size and number of the first electrodes. After the hole transport layer has been patterned, it can be wound up and stored. Further, it may be transferred to the light emitting layer forming step 204 (see FIG. 2). 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 applicator 203b uses a wet applicator 203b1 and a backup roll 203b2 that holds a strip-shaped flexible substrate 3a on which a first electrode (anode) is formed. The coating liquid for forming a hole transport layer by the wet coater 203b1 is applied to the entire surface of the strip-shaped flexible substrate 3a on which the first electrode (anode) is formed. 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 has a drying device 203c1 and a heat treatment device 203c2, and heats the hole transport 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 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.

  The pattern forming unit 203d includes a solvent applying unit 203d1, a solvent removing unit 203d2, and a drying unit 203d3. An antistatic means 203d4 and an accumulator 203d5 can be disposed between the drying unit 203d3 and the winding unit 203e as necessary.

  The solvent coating unit 203d1 includes a solvent coating device 203d12, a mounting table 203d13 for horizontally mounting the strip-shaped flexible base material 3a formed up to the hole transport layer, and a strip-shaped layer formed up to the hole transport layer. An alignment mark detector (not shown) that detects an alignment mark (not shown) attached to the flexible substrate 3a.

  In order to remove the hole transport layer between the first electrode (anode) and the first electrode (anode) adjacent to the take-out electrode of the first electrode (anode), the solvent coating device 203d12 is based on information from an alignment mark detector (not shown). A solvent (good solvent) that dissolves the transport layer is applied on the hole transport layer between the first electrode (anode) and the adjacent first electrode (anode). In addition, it is preferable that the strip-shaped flexible base material 3a on which the layers up to the hole transport layer are formed is horizontally mounted on the mounting table 203d13 so that the solvent that dissolves the applied hole transport layer does not flow out.

  The solvent coating device 203d12 is not particularly limited as long as pattern coating can be performed, and examples thereof include an ink jet head, a dispenser head, and various printing heads.

  The solvent (good solvent) that dissolves the hole transport layer is not particularly limited as long as it is a solvent that dissolves the hole transport material forming the hole transport layer. For example, when the hole transport material forming the hole transport layer is polyethylene dioxythiophene (PEDOT: PSS), water, isopropanol, and the like can be given.

In the solvent removal unit 203d2, in order to remove the solvent applied on the hole transport layer and the hole transport layer dissolved by the solvent, a process using a solvent (poor solvent) that does not dissolve the hole transport layer is performed. After the treatment, a patterned hole transport layer is formed in accordance with the first electrode (anode). Processing method in the solvent removal unit 203d2 is described in FIG.

  The solvent (poor solvent) used in the solvent removal unit 203d2 is not particularly limited as long as it does not dissolve the hole transport layer. For example, when the solvent (good solvent) applied on the hole transport layer is water. Examples of the solvent (poor solvent) used include toluene and xylene.

  The drying unit 203d3 is disposed to remove the solvent (poor solvent) used in the solvent removal unit 203d2, and has the same structure as the drying device 203c1.

  The antistatic means 203d4 has a non-contact type antistatic device 203d41 and a contact type antistatic device 203d42, and it is preferable to use the same noncontact type antistatic device 203a31 and the contact type antistatic device 203a32.

  The accumulator 203d5 has a plurality of lower transport rollers 203d51 and a plurality of upper transport rollers 203d52, and is arranged for speed adjustment at the winding unit 203e.

  In the winding unit 203e, the processing in the drying unit 203d3 is completed, and the strip-shaped flexible base material 3a on which the patterned hole transport layer is formed is wound up via the transport roll 203e1. .

  The light emitting layer forming step 204 (see FIG. 2) and the electron transport layer forming step 205 (see FIG. 2) have the same configuration as the hole transport layer forming step 203 shown in FIG. Omitted, the outline of the light emitting layer formation and the electron transport layer formation will be described.

  In the light emitting layer forming step 204 (see FIG. 2), the light emitting layer forming coating solution is applied to the entire surface by a wet coater on the strip-like flexible substrate 3a on which the patterned hole transport layer is formed. Applied. As the wet coater, it is possible to use a wet coater of the same type as the wet coater used to coat the hole transport layer forming coating solution. An alignment mark detector (not shown) is provided on the light emitting layer formed by drying in the drying section and heat treatment, and an alignment mark (not shown) attached to the strip-like flexible base material 3a by a solvent coating device. Then, based on information from an alignment mark detector (not shown), a solvent (good solvent) that dissolves the light emitting layer in accordance with the patterned hole transport layer is applied on the light emitting layer. As the coating device, it is possible to use a coating device of the same type as the coating device used for coating the solvent (good solvent) that dissolves the hole transport layer.

The solvent to be used (good solvent) is not particularly limited as long as the material constituting the light emitting layer is dissolved. For example, when the material constituting the light emitting layer uses a dicarbazole derivative (CBP) as a host material and an iridium complex (Ir (ppy) ₃ ) as a dopant material, toluene, anisole, cyclohexanone, and the like can be given.

  The solvent (poor solvent) used in the solvent removal unit is not particularly limited as long as it is a solvent (poor solvent) that does not dissolve the light emitting layer. For example, when the solvent (good solvent) for dissolving the light emitting layer is toluene, examples of the solvent (poor solvent) include acetonitrile and isopropanol.

  In the electron transport layer forming step 205 (see FIG. 2), a coating liquid for forming an electron transport layer is formed on the entire surface by a wet coater on the strip-shaped flexible substrate 3a on which the patterned light emitting layer is formed. Applied. As the wet coater, it is possible to use a wet coater of the same type as the wet coater used to coat the hole transport layer forming coating solution. An alignment mark detector (not shown) detects an alignment mark (not shown) attached to the belt-like flexible substrate 3a on the electron transport layer formed by drying and heat treatment in the drying section. Based on information from an alignment mark detector (not shown), a solvent (good solvent) that dissolves the electron transport layer in accordance with the patterned light emitting layer is applied onto the electron transport layer. As the coating device, it is possible to use a coating device of the same type as the coating device used for coating the solvent (good solvent) that dissolves the hole transport layer.

  The solvent to be used (good solvent) is not particularly limited as long as the material constituting the electron transport layer is dissolved. For example, the material constituting the electron transport layer uses 2- (4-biphenylyl) -5- (p-tertiarybutylphenyl) -1,3,4-oxadiazole (tBu-PBD). In this case, ethyl lactate and the like can be mentioned.

  The solvent (poor solvent) used in the solvent removal unit is not particularly limited as long as it is a solvent (poor solvent) that does not dissolve the electron transport layer. For example, when the solvent (good solvent) for dissolving the electron transport layer is ethyl lactate, examples of the solvent (poor solvent) include acetonitrile and isopropanol.

  FIG. 5 is a schematic diagram after the cathode buffer layer (electron injection layer) forming step shown in FIG. This figure shows a case in which a cutting device is used in the recovery process and a strip-shaped flexible substrate on which the electron transport layer is formed is used.

  The cathode buffer layer (electron injection layer) forming step 206 includes a feeding portion 206a of the strip-shaped flexible base material 3a formed up to the electron transport layer wound up in a roll shape, and includes an evaporation source container 206c. A vapor deposition device 206b and an accumulator 206d are used. The accumulator 206d has a plurality of lower conveyance rollers 206d1 and a plurality of upper conveyance rollers 206d2, and is disposed between the feeding unit 206a and the vapor deposition device 206b, and the feeding unit 206a and the vapor deposition device 206b. It is arranged for speed adjustment.

  In the cathode buffer layer (electron injection layer) forming step 206, the electron transport layer (not shown, corresponding to the electron transport layer 105 in FIG. 1) continuously supplied from the feeding portion 206a through the transport roller 206a1 is formed. An alignment mark (not shown) attached to the strip-shaped flexible substrate 3a is read by a detection device (not shown) and taken out to a position determined by the vapor deposition device 206b according to information of the detection device (not shown). Except for the electrodes, a cathode buffer layer (electron injection layer) (not shown, corresponding to the electron injection layer 107 in FIG. 1) is formed on the already formed electron transport layer as 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.

  The second electrode forming step 207 uses a vapor deposition apparatus 207a having an evaporation source container 207b and an accumulator 207c. The accumulator 207c has a plurality of lower conveyance rollers 207c1 and a plurality of upper conveyance rollers 207c2, and is disposed between the cathode buffer layer (electron injection layer) formation step 206 and the second electrode formation step 207. The cathode buffer layer (electron injection layer) forming step 206 is provided for speed adjustment.

  In the second electrode formation step 207, the cathode buffer layer (electron injection layer) continuously supplied from the cathode buffer layer (electron injection layer) formation step 206 is attached to the already formed belt-like flexible substrate 3a. An alignment mark (not shown) is read by a detection device (not shown), and a takeout electrode (not shown, takeout electrode 106a in FIG. 1) is placed at a position determined by the vapor deposition device 207a 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 is equivalent to the cathode buffer layer (electron injection layer) 106). 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 206 and the second electrode (cathode) forming step 207 are shown as a vapor deposition apparatus. 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. For example, a laser CVD method, a thermal CVD method, or the like can be used. The cathode buffer layer (electron injection layer) can also use a wet coating method.

  The sealing step 208 includes a sealing member supply step 208b, and uses a sealant coating device 208a, a bonding device 208c, and an accumulator 208e. The sealing member 208b1 is sent from the sealing member supply step 208b. The accumulator 208e has a plurality of lower transport rollers 208e1 and a plurality of upper transport rollers 208e2, and is arranged for speed adjustment with the second electrode (cathode) forming step 207.

  Note that an alignment mark (not shown) is attached to the sealing member 208b1 at the same position as the alignment mark (not shown) attached to the strip-shaped flexible substrate 3a in which the second electrode is already formed. Yes.

  In the sealing step 208, an alignment mark (not shown) attached to the strip-like flexible base material 3a where the second electrode has already been formed is read by a detection device (not shown), and the detection device (not shown) In accordance with the information, the sealant coating device 208a is coated on the organic EL element at the top and the periphery except for the extraction electrodes (not shown, corresponding to the extraction electrodes 102a and 107a in FIG. 1).

  Thereafter, an alignment mark (not shown) and a sealing member 208b1 attached to the strip-shaped flexible base material 3a having a plurality of organic EL elements formed by applying a sealing agent by the bonding device 208c. Together with the alignment mark (not shown), the organic EL element is tightly sealed. At this stage, an organic EL panel is manufactured. Since a plurality of organic EL panels manufactured at this stage are continuously connected, they are cut into individual organic EL panels in the recovery step 209.

  The collection step 209 uses a cutting device 209a, an accumulator 209b, and a collection box 209c. The accumulator 209 b has a plurality of lower conveyance rollers 209 b 1 and a plurality of upper conveyance rollers 209 b 2, and is arranged for speed adjustment with the sealing step 208. In the cutting device 209a, 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 208b1. And is cut and punched according to the information of the detection device (not shown), and is collected as an individual organic EL panel 6 in the collection box 209c. Reference numeral 209d denotes a skeleton wound in a roll shape from which an organic EL panel is punched. The cut organic EL panel 6 has the same configuration as the organic EL panel shown in FIG.

  FIG. 6 is a schematic view of the removal method of the solvent removal unit shown in FIG. FIG. 6A is a schematic diagram when the removal method of the solvent removal unit shown in FIG. 4 is a rinse method. FIG. 6B is a schematic diagram when the removal method of the solvent removal unit shown in FIG. 4 is an immersion method.

  The rinsing method of FIG. In the figure, 203d21 indicates a rinsing type solvent removal apparatus. The solvent removal device 203d21 includes a main body 203d211, a solvent (poor solvent) supply unit 203d212, and a receiver 203d214. The solvent (poor solvent) is supplied from the supply pipe 203d213 to the hole transport layer side of the strip-shaped flexible substrate 3a in which the solvent (good solvent) is applied on the hole transport layer conveyed from the previous step. 203d212. As a supply method, a spray method, a discharge method, or the like is preferable for effective removal. The solvent in which the hole transport layer is dissolved (good solvent) and the supplied solvent (poor solvent) are received by the receiver 203d214 and collected by the discharge pipe 203d215.

The dipping method in FIG. 6B will be described. Reference numeral 203d22 denotes an immersion type solvent removal apparatus. The solvent removal apparatus 203d22 has a dipping tank 203d221 having a solvent (poor solvent) supply pipe 203d222, a discharge pipe 203d223, and stirring means (not shown). By immersing the strip-shaped flexible base material 3a in which the solvent (good solvent) is applied on the hole transport layer conveyed from the previous step in the immersion tank 203d221 filled with the solvent (poor solvent). solvent on the hole transport layer (good solvent) is it Do to as being removed. Note that the solvent (poor solvent) in the dipping bath 203d221 is effective for removing the solvent (good solvent) on the hole transport layer and from the dipping bath 203d221 along with the conveyance of the strip-shaped flexible substrate 3a. In order to correct the amount taken out, it is preferable to always supply a new solvent (poor solvent) from the solvent (poor solvent) supply pipe 203d222 at a constant rate. Further, in order to effectively remove the solvent (good solvent) on the hole transport layer, the solvent (poor solvent) in the immersion tank 203d221 is preferably stirred by a stirring means (not shown). There is no particular limitation on the stirring means (not shown), but for example, a jetting method in which a solvent (poor solvent) is jetted onto the hole transport layer side on the belt-like flexible substrate 3a is preferable.

    FIG. 7 is a schematic flow diagram showing patterning of the hole transport layer in the hole transport layer forming step shown in FIG. Hereinafter, the patterning of the hole transport layer formed on the entire surface of the belt-like flexible substrate on which the first electrode (anode) is formed will be described with reference to the flowchart.

  Step 1 shows the strip-shaped flexible substrate 3a in which a plurality of anodes (first electrodes) 4 are formed in the first electrode forming step 202 (see FIG. 2). 4a denotes an extraction electrode. The right side is a schematic cross-sectional view along the line CC 'in the drawing shown in Step 1.

  Step 2 shows the strip-shaped flexible substrate 3a on which the hole transport layer 5 is formed in the hole transport layer forming step 203 (see FIG. 2). The hole transport layer is formed on the entire surface except for both ends of the belt-like flexible substrate including the plurality of anodes (first electrodes) 4. The right side is a schematic cross-sectional view along the line DD 'in the drawing shown in Step 2.

  In Step 3, holes are formed between the take-out electrode 4a of the anode (first electrode) 4 and the periphery of the adjacent anode (first electrode) 4 by the solvent application unit 203d12 (see FIG. 4) of the solvent application unit 203d1 (see FIG. 4). The solvent (good solvent) which melt | dissolves the transport layer 5 is apply | coated (the part shown with the oblique line in a figure). The right side is a schematic cross-sectional view along the line EE ′ in the drawing shown in Step 3.

  Step 4 is a solvent (poor solvent) that does not dissolve the hole transport layer 5 in the solvent removal unit 203d2 (see FIG. 4), and the anode (first electrode) 4 adjacent to the extraction electrode 4a of the anode (first electrode) 4 is used. The state where the solvent (good solvent) including the hole transport layer 5 dissolved by the surrounding and the applied solvent (good solvent) is removed is shown. When Step 4 is completed, the extraction electrode 4a of the anode (first electrode) 4 is exposed, and the hole transport layer 5 is formed on and around the anode (first electrode) 4. The right side is a schematic cross-sectional view along the line FF ′ in the figure shown in Step 4.

  Thereafter, the light emitting layer is formed on the hole transport layer 5 according to the flow of Step 1 to Step 4, and the electron transport layer is similarly formed on the light emitting layer according to the flow of Step 1 to Step 4.

After forming the hole transport layer, the light emitting layer, and the electron transport layer on the entire surface by the roll-to-roll method in the manufacturing process shown in FIGS. 2 to 7, a solvent (good solvent) that dissolves each layer is applied to unnecessary portions. After dissolving unnecessary portions of each layer, the following effects can be obtained by removing the solvent (good solvent) and each dissolved layer with a solvent (poor solvent) that does not dissolve each layer to produce an organic EL panel.
1. Each layer can be formed easily, and the production efficiency can be improved by the roll-to-roll method.
2. It was possible to improve the non-uniformity of the film thickness distribution at the center and end of each coating area, which was a problem in the pattern method.
3. Since physical peeling is not performed, particles generated at the time of peeling are suppressed, and the yield such as pinhole defects can be improved.

  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 refers to the 0-0 band peak energy of phosphorescence emission measured by measuring the photoluminescence of a deposited film of 100 nm 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 ° viewing angle front luminance is measured by the above method. It is in the 0.07 region.

  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.

(Electron transport layer)
The electron transport layer is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single layer or a plurality of layers.

  Conventionally, in the case of a single electron transport layer and a plurality of layers, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the light emitting layer on the cathode side is injected from the cathode. As long as it has a function of transferring electrons to the light-emitting layer, any material can be selected and used from the conventionally known compounds, such as nitro-substituted fluorene derivatives and diphenylquinone derivatives. Thiopyrandioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives and the like. Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an 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.

Also, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq ₃ ), 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), etc., 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. In addition, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as an electron transporting material, and an inorganic semiconductor such as n-type-Si, n-type-SiC, etc., like the hole injection layer and the hole transporting layer. Can also be used as an electron transporting material.

  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 nm-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

(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.

Also, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq ₃ ), 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), etc., 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, Magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred. 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, and the light is guided through the transparent electrode or the light emitting layer.

  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 500 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. 3, the alignment mark of the prepared PET is detected, and ITO (indium tin oxide) having a thickness of 120 nm is sputtered onto the alignment mark according to the position of the alignment mark under a vacuum environment condition of 5 × 10 ⁻¹ Pa. Then, a mask pattern was formed, and 10 mm × 10 mm first electrodes having take-out electrodes were continuously formed in 12 rows at regular intervals, and wound up and stored for 1 hour.

(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 mN / m (manufactured by Kyowa Interface Chemical Co., Ltd .: surface tension meter CBVP-A3).

(Formation of hole transport layer)
Using the apparatus shown in FIG. 4, after the prepared roll-shaped PET having the first electrode formed thereon is subjected to charge removal treatment, a hole transport layer is formed on the entire upper surface of the PET (except 10 mm at both ends). The coating solution for coating was applied by the wet coating method using an extrusion coating machine under the following conditions so that the thickness after drying was 30 nm. After coating, a drying / heating treatment was performed in the drying section under the following conditions to form a hole transport layer. The conveyance speed was 3 m / min. The conveyance speed was measured with a laser Doppler velocimeter LV203 manufactured by Mitsubishi Electric Corporation.

  For the charge removal treatment, a non-contact type antistatic device was used on the first electrode formation side, and a contact type antistatic device was used on the back side. As the non-contact type antistatic device, a flexible AC ionizing bar MODEL4100V manufactured by Hugle Electronics Co., Ltd. was used. The contact-type antistatic device was a conductive guide roll ME-102 manufactured by Miyako Roller Industry Co., Ltd.

Coating conditions As coating conditions for the hole transport layer forming coating solution, the temperature during coating of the hole transport layer forming coating solution is 25 ° C. under an atmospheric pressure of N ₂ gas environment with a dew point temperature of −20 ° C. or lower. And it was performed with a cleanliness class of 5 or less (JIS B 9920).

Drying and Heating Treatment Conditions Drying and heating treatment conditions for the coating film for forming the hole transport layer are as follows. After the coating liquid for forming the hole transport layer is applied, the drying device and the heat treatment device shown in FIG. Then, after removing the solvent at a height of 100 mm from the slit nozzle type discharge port toward the film formation surface, a discharge wind speed of 1 m / s, a wide wind speed distribution of 5%, and a temperature of 120 ° C., a temperature of 150 ° C. is continuously applied by a heat treatment apparatus. The back surface heat transfer system heat treatment was performed to form a hole transport layer.

(Pattern of hole transport layer)
According to the flow shown in FIG. 7, the alignment mark attached to the PET is detected, and on the hole transport layer formed on the PET according to the position of the alignment mark, on the extraction electrode portion of the first electrode and on the first electrode Pure water, which is a good solvent for the hole transport layer, was applied to unnecessary portions around the electrode at a temperature of 25 ° C. by inkjet so that the wet film thickness was 5 μm. Subsequently, using the poor solvent toluene (bp 110 ° C.) with respect to the hole transport layer, treated with the rinse method shown in FIG. The transport layer was removed, dried with a drying apparatus to pattern the hole transport layer, and then wound up and stored for 1 hour. The supply amount of the poor solvent was 500 ml / min and the temperature was 25 ° C.

(Preparation of light emitting layer forming coating solution)
Dicarbazole derivative (CBP) 1.00% by mass
Iridium complex (Ir (ppy) ₃ ) 0.05% by mass
Toluene 98.95% by mass
The surface tension of the light emitting layer forming coating solution was 28 mN / m at 25 ° C. (manufactured by Kyowa Interface Chemical Co., Ltd .: using surface tension meter CBVP-A3).

(Formation of light emitting layer)
After the prepared roll-shaped PET on which the hole transport layer is formed is charged and removed, the coating solution for forming the light emitting layer is extruded at a temperature of 25 ° C. on the entire upper surface of the PET (however, excluding 10 mm at both ends). It apply | coated so that the dry film thickness might be set to 50 nm with the wet application | coating system using an applicator. After coating, drying and heat treatment were performed in the drying section to form a light emitting layer. The conveyance speed was 3 m / min. The conveyance speed was measured with a laser Doppler velocimeter LV203 manufactured by Mitsubishi Electric Corporation.

  For the charge removal treatment, a non-contact type antistatic device was used on the hole transport layer side, and a contact type antistatic device was used on the back side. As the non-contact type antistatic device, a flexible AC ionizing bar MODEL4100V manufactured by Hugle Electronics Co., Ltd. was used. The contact-type antistatic device was a conductive guide roll ME-102 manufactured by Miyako Roller Industry Co., Ltd.

Application conditions The application conditions for the light-emitting layer are as follows: the temperature during application of the light-emitting layer-forming coating solution is 25 ° C., 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).

Drying and Heating Treatment Conditions Drying and heating treatment conditions for the light emitting layer forming coating film were applied to the light emitting layer forming coating solution, and then used for drying and heat treatment of the hole transport layer coating film shown in FIG. In addition, the drying apparatus uses the same apparatus as the heat treatment apparatus, and the drying apparatus has a height of 100 mm from the slit nozzle type discharge port toward the film-forming surface, a discharge air speed of 1 m / s, a wide wind speed distribution of 5%, and a temperature of 60 ° C. After the removal, subsequently, a heat treatment by a back surface heat transfer method was performed at a temperature of 150 ° C. by a heat treatment apparatus to form a light emitting layer.

(Light emitting layer patterning)
According to the flow shown in FIG. 7, the alignment mark attached to the PET is detected, and on the light emitting layer formed on the PET according to the position of the alignment mark, on the extraction electrode portion of the first electrode and on the hole transport layer. Toluene, which is a good solvent for the light emitting layer, was applied to the surrounding unnecessary portion by ink jetting at a temperature of 25 ° C. so that the wet film thickness was 5 μm. Subsequently, acetonitrile (b.p. 82 ° C.), which is a poor solvent for the light emitting layer, is treated by the rinsing method shown in FIG. 6A to remove the light emitting layer dissolved by the good solvent and the good solvent. Then, after drying with a drying apparatus and patterning the light emitting layer, it was wound up and stored for 1 hour. The supply amount of the poor solvent was 500 ml / min and the temperature was 25 ° C.

(Preparation of coating solution for electron transport layer formation)
2- (4-biphenylyl) -5- (p-tertiarybutylphenyl) -1,3,4-oxadiazole (tBu-PBD) 1% by mass
99% by mass of ethyl lactate
The surface tension of the coating liquid for forming an electron transport layer was 29 mN / m at 25 ° C. (manufactured by Kyowa Interface Chemical Co., Ltd .: using a surface tension meter CBVP-A3).

(Formation of electron transport layer)
After the prepared PET having a light emitting layer formed thereon is subjected to a charge removal treatment, the electron transport layer forming coating solution is applied by extrusion at a temperature of 25 ° C. on the entire upper surface of the PET (except 10 mm at both ends). The film was applied by a wet coating method using a machine so that the dry film thickness was 30 nm. After coating, drying and heat treatment were performed in the drying section to form an electron transport layer. The conveyance speed was 3 m / min. The conveyance speed was measured with a laser Doppler velocimeter LV203 manufactured by Mitsubishi Electric Corporation.

  For the charge removal treatment, a non-contact type antistatic device was used on the light emitting layer side, and a contact type antistatic device was used on the back side. As the non-contact type antistatic device, a flexible AC ionizing bar MODEL4100V manufactured by Hugle Electronics Co., Ltd. was used. The contact-type antistatic device was a conductive guide roll ME-102 manufactured by Miyako Roller Industry Co., Ltd.

Coating conditions The coating conditions for the electron transport layer are as follows: the temperature during coating of the coating liquid for forming the electron 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 or less. (JIS B 9920).

Drying and Heating Treatment Conditions Drying and heating treatment conditions for the electron transport layer forming coating were applied to the electron transport layer forming coating solution and then used for drying and heating the hole transporting layer coating shown in FIG. The same apparatus as the drying apparatus and heat treatment apparatus is used. In the drying apparatus, the height from the slit nozzle type discharge port to the film formation surface is 100 mm, the discharge wind speed is 1 m / s, the width of the wide wind speed is 5%, and the temperature is 150. After removing the solvent, the back surface heat transfer system heat treatment was subsequently carried out at a temperature of 100 ° C. with a heat treatment apparatus to form an electron transport layer.

(Patternization of electron transport layer)
According to the flow shown in FIG. 7, the alignment mark attached to the PET is detected, and on the electron transport layer formed on the PET according to the position of the alignment mark, on the extraction electrode portion of the first electrode and on the light emitting layer. On the surrounding unnecessary portion, ethyl lactate, which is a good solvent for the electron transport layer, was applied by ink jetting at a temperature of 25 ° C. so as to have a wet film thickness of 5 μm. Subsequently, acetonitrile (b.p. 82 ° C.), which is a poor solvent for the electron transport layer, was treated by the rinse method shown in FIG. After removing and drying with a drying apparatus to pattern the electron transport layer, it was wound up and stored for 1 hour. The supply amount of the poor solvent was 500 ml / min and the temperature was 25 ° C.

(Production of organic EL panel)
Using the process shown in FIG. 5, a cathode buffer layer (electron injection layer), a second electrode, and a sealing layer are sequentially formed on the electron transport layer under the conditions shown below, and cut to produce an organic EL panel. Sample No. 101.

(Formation of cathode buffer layer (electron injection layer))
The alignment mark attached to the roll-shaped PET on which the prepared patterned electron transport layer is formed is detected, and the periphery on the electron transport layer and the first electrode excluding the extraction electrode according to the position of the alignment mark; In addition, a mask pattern was formed by vapor deposition using LiF as a cathode buffer layer (electron injection layer) layer forming material in a vacuum environment condition of 5 × 10 ⁻⁴ Pa with a vapor deposition apparatus, and a cathode having a thickness of 0.5 nm A buffer layer (electron injection layer) was stacked.

(Formation of second electrode)
Subsequently, an alignment mark attached to the PET is detected, and a vacuum of 5 × 10 ⁻⁴ Pa is formed on the cathode buffer layer (electron injection layer) formed according to the position of the alignment mark in accordance with the size of the first electrode. Then, aluminum was used as the second electrode forming material, a mask pattern was formed by a vapor deposition method so as to have an extraction electrode, and a second electrode having a thickness of 100 nm was laminated to produce an organic EL element.

(Applying adhesive)
An alignment mark affixed to the PET of the produced organic EL element is detected, and an ultraviolet curable type is formed around the light emitting region and the light emitting region except for the ends of the first electrode and the lead electrode of the second electrode according to the position of the alignment mark. A liquid adhesive (epoxy resin type) was used, and the coating was applied at a thickness of 30 μm.

(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 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)
In the state in which a plurality of prepared organic EL panels are continuously connected, the alignment mark attached to the PET in the size of the individual organic EL panel was detected, and cut according to the position of the alignment mark.

(Preparation of comparative sample No. 102)
<Preparation of strip-shaped flexible substrate>
Sample No. The same PET as 101 was prepared.

(Formation of the first electrode)
Sample No. The first electrode was formed under the same conditions as 101, and was wound up and stored for 1 hour.

(Preparation of coating solution for hole transport layer formation)
Sample No. The same hole transport layer forming coating solution as 101 was prepared.

(Formation of hole transport layer)
After the prepared roll-shaped PET on which the first electrode is formed is subjected to a charge removal treatment, an alignment mark attached to the PET is detected, and a coating liquid for forming a hole transport layer is used by an ink jet according to the position of the alignment mark. A pattern was applied on the first electrode and around the first electrode under the conditions shown below so that the dry film thickness was 30 nm, except for the first electrode extraction electrode forming portion. After coating, the drying part was dried and heated under the following conditions to form a hole transport layer, which was wound up and stored for 1 hour. The conveyance speed was 1 m / min in order to ensure the stability of pattern application. The conveyance speed was measured with a laser Doppler velocimeter LV203 manufactured by Mitsubishi Electric Corporation. The charge removal treatment is performed using sample no. The same conditions as in 101 were used.

Application conditions The application conditions for the coating solution for forming the hole transport layer are as follows: Sample No. The same conditions as in 101 were used.

Drying and Heating Treatment Conditions As the drying and heat treatment conditions of the coating film for forming the hole transport layer, Sample No. The same conditions as in 101 were used.

(Preparation of light emitting layer forming coating solution)
Sample No. The same light emitting layer forming coating solution as 101 was prepared.

(Formation of light emitting layer)
After the prepared roll-shaped PET on which the hole transport layer is formed is charged and removed, an alignment mark attached to the PET is detected, and a light-emitting layer forming coating liquid is ink-jetted onto the PET according to the position of the alignment mark. Was applied on the hole transport layer and the periphery of the hole transport layer under the conditions shown below so that the dry film thickness was 50 nm, except for the extraction electrode forming part of the first electrode. After application, the drying part was dried and heated under the conditions shown below to form a light emitting layer, which was wound up and stored for 1 hour. The conveyance speed was 1 m / min in order to ensure the stability of pattern application. The conveyance speed was measured with a laser Doppler velocimeter LV203 manufactured by Mitsubishi Electric Corporation. The charge removal treatment is performed using sample no. The same conditions as in 101 were used.

Application conditions As the application conditions of the light emitting layer forming coating solution, Sample No. The same conditions as in 101 were used.

Drying and heat treatment conditions As the drying and heat treatment conditions of the light-emitting layer-forming coating film, sample no. The same conditions as in 101 were used.

(Formation of electron transport layer)
The roll-shaped PET on which the prepared light emitting layer is formed is subjected to an electrification removing process, and then an alignment mark attached to the PET is detected, and an electron transport layer forming coating liquid is applied onto the PET according to the position of the alignment mark by an inkjet. The coating was applied on the light emitting layer and the periphery of the light emitting layer under the conditions shown below so that the dry film thickness was 30 nm. After application, the drying part was dried and heated under the conditions shown below to form a light emitting layer, which was wound up and stored for 1 hour. The conveyance speed was 1 m / min in order to ensure the stability of pattern application. The conveyance speed was measured with a laser Doppler velocimeter LV203 manufactured by Mitsubishi Electric Corporation. The charge removal treatment is performed using sample no. The same conditions as in 101 were used.

Application conditions As application conditions for the electron transport layer forming coating solution, Sample No. The same conditions as in 101 were used.

Drying and Heating Treatment Conditions As sample drying and heating treatment conditions for the coating film for electron transport formation, Sample No. The same conditions as in 101 were used.

(Production of organic EL panel)
Using the process shown in FIG. A cathode buffer layer (electron injection layer), a second electrode, and a sealing layer are sequentially formed on the electron transport layer under the same conditions as in 101, and cut to produce an organic EL panel. 102.

(Preparation of comparative sample No. 103)
<Preparation of strip-shaped flexible substrate>
Sample No. The same PET as 101 was prepared.

(Formation of the first electrode)
Sample No. The first electrode was formed under the same conditions as 101, and was wound up and stored for 1 hour.

(Preparation of coating solution for hole transport layer formation)
Sample No. The same hole transport layer forming coating solution as 101 was prepared.

(Formation of hole transport layer)
Sample No. The hole transport layer forming coating solution was applied to the entire upper surface of PET (except 10 mm at both ends) under the same conditions as 101 by a wet coating method using an extrusion coating machine so that the dry film thickness was 30 nm. . After application, sample no. Drying and heat treatment were performed under the same conditions as 101 to form a hole transport layer. The conveyance speed was 3 m / min.

(Pattern of hole transport layer)
An alignment mark attached to the PET is detected, and unnecessary portions on the extraction electrode portion of the first electrode and around the first electrode are formed on the hole transport layer formed on the PET according to the position of the alignment mark. Further, pure water, which is a good solvent, was applied to the hole transport layer at 25 ° C. by inkjet so that the wet film thickness was 5 μm. Subsequently, the applied good solvent and the hole transport layer dissolved in the good solvent were removed by wiping with a roll wiper, dried with a drying apparatus to pattern the hole transport layer, and then wound up and stored for 1 hour.

(Preparation of light emitting layer forming coating solution)
Sample No. The same light emitting layer forming coating solution as 101 was prepared.

(Formation of light emitting layer)
Sample No. The light emitting layer forming coating solution was applied to the entire upper surface of PET (except 10 mm at both ends) under the same conditions as 101 by a wet coating method using an extrusion coating machine so that the dry film thickness was 50 nm. After application, sample no. Drying and heat treatment were performed under the same conditions as 101 to form a hole transport layer. The conveyance speed was 3 m / min.

(Light emitting layer patterning)
An alignment mark attached to the PET is detected, and on the light emitting layer formed on the PET according to the position of the alignment mark, on the extraction electrode portion of the first electrode and on an unnecessary portion around the hole transport layer. Then, toluene, which is a good solvent, was applied to the light emitting layer by ink jetting at a temperature of 25 ° C. so that the wet film thickness was 5 μm. Subsequently, the applied good solvent and the light-emitting layer dissolved in the good solvent were wiped off with a roll wiper, and the light-emitting layer was patterned by drying with a drying apparatus, and then wound up and stored for 1 hour.

(Preparation of coating solution for electron transport layer formation)
Sample No. The same electron transport layer forming coating solution as 101 was prepared.

(Formation of electron transport layer)
Sample No. The coating solution for forming an electron transport layer was coated on the entire upper surface of PET (except 10 mm at both ends) under the same conditions as 101 by a wet coating method using an extrusion coating machine so that the dry film thickness was 30 nm. After application, sample no. Drying and heat treatment were performed under the same conditions as in 101 to form an electron transport layer. The conveyance speed was 3 m / min.

(Patternization of electron transport layer)
An alignment mark attached to the PET is detected, on the electron transport layer formed on the PET according to the position of the alignment mark, on an extraction electrode portion of the first electrode and an unnecessary portion around the light emitting layer, Ethyl lactate, which is a good solvent, was applied to the electron transport layer at 25 ° C. by inkjet so that the wet film thickness was 5 μm. Subsequently, the applied good solvent and the light-emitting layer dissolved in the good solvent were removed by wiping with a roll wiper, dried with a drying apparatus to pattern the electron transport layer, and then wound up and stored for 1 hour.

(Production of organic EL panel)
Using the process shown in FIG. A cathode buffer layer (electron injection layer), a second electrode, and a sealing layer are sequentially formed on the electron transport layer under the same conditions as in 101, and cut to produce an organic EL panel. 103.

Evaluation Each sample No. Samples are taken from the first 5 m and the last 5 m on 101 to 103, and production efficiency, leakage current characteristics, and dark spots (spot-shaped non-light emitting parts) are tested by the test methods shown below. The results of evaluation according to the evaluation rank are shown in Table 1.

Production efficiency The time required to produce an organic EL panel on PET having a width of 200 mm and a length of 500 m was defined as production efficiency.

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. It was confirmed that No. 101 can produce a stable organic EL panel with a short production time, good leakage current characteristics, and a small number of dark spots with high production efficiency.

  Organic EL panel No. It was confirmed that No. 102 is an unstable organic EL panel in which nonuniformity of the film thickness distribution occurs, leakage current characteristics are inferior, and the number of dark spots is large. It was also confirmed that the production time was long and the production efficiency was low.

  Organic EL panel No. 103, the production time was the same as that of the present invention, but it was confirmed that particles due to physical peeling occurred, the leakage current characteristics were inferior, the number of dark spots was large, and the performance was inferior. . 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 by a roll-to-roll system using a strip | belt-shaped flexible base material. It is a schematic diagram to the supply process shown in FIG. 2, and a 1st electrode formation process. It is a schematic diagram of the positive hole transport layer formation process shown in FIG. FIG. 3 is a schematic diagram after the cathode buffer layer (electron injection layer) forming step shown in FIG. 2. It is the schematic of the removal system of the solvent removal part shown in FIG. FIG. 5 is a schematic flow diagram showing patterning of a hole transport layer in the hole transport layer forming step shown in FIG. 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic electroluminescent panel 101 Flexible base material 102, 4 Anode (1st electrode)
102a, 107a, 4a Extraction electrode 103, 5 Hole transport layer 104 Light emitting layer 105 Electron transport layer 106 Cathode buffer layer (electron injection layer)
107 Cathode (second electrode)
DESCRIPTION OF SYMBOLS 108 Adhesive layer 109 Sealing member 2 Manufacturing process 201 Supply process 202 1st electrode formation process 202a 1st electrode formation apparatus 203 Hole transport layer formation process 203b Application | coating part 203b1 Wet application machine 203d Pattern formation part 203d1 Solvent application part 203d12 Solvent Coating device 203d2 Solvent removal unit 203d21, 203d22 Solvent removal device 203d212 Solvent (poor solvent) supply unit 203d213 Supply tube 203d214 Receiver 203d221 Immersion tank 203d222 Solvent (poor solvent) supply tube 203d223 Discharge tube 203d3 Drying unit 204 Light emitting layer forming step 205 Electron Transport layer forming process 206 Cathode buffer layer (electron injection layer) forming process 207 Second electrode forming process 208 Sealing process 209 Recovery process 3, 3a Strip-shaped flexible substrate 301 Roll-shaped flexible substrate

Claims (7)

A roll-to-roll organic electroluminescence panel comprising a first electrode, at least one organic functional layer, a second electrode, and a sealing layer on a continuous flexible resin film that is transported continuously In the manufacturing method of the organic electroluminescence panel manufactured by the method,
After applying the organic functional layer coating solution by a wet coating method on the entire surface of the front Symbol first electrode and dried to form the organic functional layer,
The good solvent for dissolving the organic functional layer to unwanted areas of the organic functional layer pattern applied to dissolve the unnecessary region in the good solvent,
Using a poor solvent that does not dissolve the organic functional layer, wherein by a good solvent unnecessary area is dissolved processed and removed, and forming by patterning the organic functional layer at least one layer Manufacturing method of organic electroluminescence panel. Method of producing an organic electroluminescent panel according to claim 1 wherein the pattern coating is characterized by Rukoto performed by a droplet discharge method.   The method for producing an organic electroluminescence panel according to claim 1, wherein the treatment with the poor solvent is a rinse method or an immersion method.   An organic electroluminescent lighting device using the organic electroluminescent element manufactured by the method for manufacturing an organic electroluminescent panel according to claim 1. A roll-to-roll organic electroluminescence panel comprising a first electrode, at least one organic functional layer, a second electrode, and a sealing layer on a continuous flexible resin film that is transported continuously In an organic electroluminescence panel manufacturing apparatus manufactured by a method,
A coating means for applying a coating liquid for forming an organic functional layer on the entire surface of the first electrode by a wet coating method;
Drying means for drying the organic functional layer forming coating solution to form the organic functional layer;
Pattern coating means for pattern-coating a good solvent that dissolves the organic functional layer with respect to an unnecessary region of the organic functional layer;
An apparatus for manufacturing an organic electroluminescence panel, comprising: a solvent removing unit that processes and removes the good solvent in which the unnecessary region is dissolved using a poor solvent that does not dissolve the organic functional layer. 6. The organic electroluminescence panel manufacturing apparatus according to claim 5, wherein the pattern coating unit is a unit using a droplet discharge method. 7. The organic electroluminescence panel manufacturing apparatus according to claim 5, wherein the solvent removing means is a means using a rinsing method or a dipping method.

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