JP4992432B2 - Organic functional layer, organic functional element manufacturing method, and organic functional element manufacturing apparatus - Google Patents

Description

The present invention relates to an apparatus for manufacturing an organic film coated on a substrate. Moreover, it is related with the manufacturing method of organic functional elements, such as an organic electroluminescent element (henceforth an organic EL element) including an drying process, an organic solar cell, and an organic functional layer transistor.

In recent years, organic functional elements such as organic EL elements using organic functional materials, organic solar cells, and organic functional layer transistors have been actively developed with the aim of reducing the weight and flexibility of electronic components. Yes. These organic functional elements generally require an organic functional layer having a film thickness of about several tens to several thousand nm to be patterned on a substrate.

Organic functional materials include low-molecular materials and high-molecular materials. In general, low-molecular materials are formed into thin films by resistance heating vapor deposition or the like, and then patterned using a fine pattern mask. There is a problem that the patterning accuracy becomes difficult as the size of the substrate increases. Further, in the vapor deposition method, the vapor deposition source is usually a point shape such as a pinhole or a crucible of a boat, so that it is difficult to form a layer with a uniform film thickness on a large-sized substrate. In addition, the vapor deposition method is often performed under high vacuum, which requires a large vacuum apparatus.

On the other hand, a method of forming a thin film by a wet process using a coating liquid (ink) in which an organic functional material is dissolved or dispersed in a solvent has been tried. Examples of wet coating methods for forming a thin film include spin coating, bar coating, and dip coating. In particular, for high-definition patterning, it is considered that thin film formation by a printing method that specializes in coating and patterning is most effective (for example, Patent Documents 1, 2, 3, and Non-Patent Document 1).

A method for producing an organic functional element by a printing method is very effective. In particular, when a polymer material is used, it is possible to easily form a flat and uniform organic functional layer on the substrate. However, since the organic functional layer printed on the substrate contains a solvent, a drying step for removing the solvent is required. As the method, a method using a reduced pressure drying method (for example, Patent Document 4), a heat drying method (for example, Patent Document 5), and a pressure heat drying method (Patent Document 6) has been proposed.
JP 2003-17261 A Special table 2003-527955 gazette JP-T-2005-531134 JP-A-9-97679 JP 2002-31567 A JP 2005-26000 A 142th Committee C of Organic Materials for Information Science (Organic Optoelectronics) 5th Workshop Material Organic Functional Layer Solar Cells by Printing Process (pages 20-27)

However, usually, an organic functional layer is formed on a substrate by a printing method such as a relief printing method (flexographic printing method), an intaglio offset printing method, a relief printing reverse offset printing method, an ink jet printing method, or an intaglio printing method. In the case of manufacturing, in order to prevent drying of the coating liquid during the printing process, a solvent having a boiling point of 150 degrees or higher at atmospheric pressure is often used. The solvent cannot be sufficiently removed from the organic functional layer by heat drying at. And there existed a problem that the characteristic of an organic functional element fell or deteriorated compared with the case where a high boiling point solvent is not used by such a high boiling point solvent remaining in an organic functional layer.

In addition, if a high temperature is applied to sufficiently dry for the purpose of removing the high boiling point solvent (hereinafter referred to as residual solvent) remaining in the organic functional layer, the material constituting the organic functional element may be deteriorated. Furthermore, when a plastic film is used for the substrate when aiming at weight reduction / flexibility, there is a problem that the substrate itself undergoes shape change or deterioration due to high heat. In addition, when oxygen and water coexist at the time of heating, they cause a chemical reaction with the organic functional layer and deteriorate the device characteristics. In particular, oxygen easily reacts with the double bond sites of π-electron molecules that are often used as functional materials. Therefore, when drying the organic functional layer at a high temperature, it must be performed in an inert atmosphere such as nitrogen or argon. There are many cases.

Therefore, the present invention has been made in view of such circumstances, and even when the organic functional layer is produced by a printing method, the characteristics of the organic functional element are not deteriorated due to the removal of the residual solvent, and the performance is high. Provided is a method for producing an organic film capable of producing an organic functional element, and further provides a method for producing an organic EL element, an organic solar cell, and an organic functional layer transistor, which are organic functional elements using the production method. Is an issue.

This invention is made | formed in view of said subject, Comprising: At the time of solvent drying, the residual solvent (1st solvent) in an organic functional layer is chemically inert, highly volatile, and highly volatile. It has been found that the above problem can be solved by substituting with a solvent (second solvent).

The invention according to claim 1 is an organic function comprising the coating film, wherein a coating liquid in which an organic functional material is dissolved or dispersed in a first organic solvent is used as a coating film on a substrate using a printing method. A method for producing a layer, wherein the coating film is chemically inert and does not dissolve in an organic functional material, but penetrates into the solvent (first solvent) of the functional layer coating solution, Using a dry solvent (second solvent) with a high vapor pressure at the construction temperature, the substrate on which the organic functional layer is formed is immersed in the dry solvent or brought into contact with the vapor of the dry solvent, that is, in a solvent atmosphere. It is a manufacturing method of the organic functional layer dried by the process of exposing an organic functional layer.

The invention according to claim 2 is a method for producing the organic functional layer, wherein the substrate is immersed in a rinsing tank filled with the liquid second solvent, and then the vapor of the second solvent is used. And a step of bringing the substrate into contact with the organic functional layer.

The invention according to claim 3 is the method for producing the organic functional layer, wherein the substrate is cooled to a temperature of 10 ° C. or more and 25 ° C. or less, and is heated and gasified in the atmosphere of the second solvent. It is a manufacturing method of the organic functional layer characterized by having the process of contacting the coating film on the board | substrate.

The invention according to claim 4 is the method for manufacturing the organic functional layer, wherein the mist-like second solvent is sprayed on the substrate.
The invention according to claim 5 is a method for producing the organic functional layer, comprising the steps of bringing the coating film into contact with the second solvent, and then heating the substrate. And the said process is performed in the same space filled with inert gas atmosphere, It is a manufacturing method of the organic functional layer characterized by the above-mentioned.

Further, in the invention according to claim 6, when the organic functional layer is immersed in the liquid of the second solvent, the organic after 24 hours from the immersion to the surface roughness Ra of the organic functional layer immediately after the immersion. The change rate of the surface roughness Ra of the functional layer is less than 1%, and the weight of the organic functional layer dissolved in the second solvent after 24 hours is 0. 0% of the weight of the organic functional layer after the drying step. The method for producing an organic functional layer according to any one of claims 1 to 5, wherein a solvent satisfying less than 1% is used as the second organic solvent.

The invention according to claim 7 is the method for producing an organic functional layer according to any one of claims 1 to 4, wherein the surface tension of the second solvent is 25 mN / m or less. .
The organic functional layer according to any one of claims 1 to 7, wherein the second solvent is a solvent containing 5 or more fluorine atoms in one molecule. It is a manufacturing method.

Further, the invention according to claim 9 is a manufacturing process of an organic functional element including an organic functional layer.
The organic functional layer manufacturing method according to claim 1, wherein the organic functional layer manufacturing method according to claim 1 is used as at least one organic functional layer.

Furthermore, as a manufacturing apparatus for realizing the manufacturing method of the organic functional layer and the organic functional element, the invention according to claim 10 includes a substrate holder having means for moving the substrate in the apparatus, and an ultrasonic oscillation device, An organic tank comprising: an ultrasonic tank capable of holding a liquid of a dry solvent; a rinse tank capable of holding a liquid of a dry solvent; and a vapor tank provided with a means for generating a vapor of the dry solvent. It is a functional element manufacturing apparatus.

The invention according to claim 11 is a steam tank provided with means for generating a vapor of a dry solvent, a substrate installation part installed immediately above the steam tank, and a substrate cooler connected to the substrate installation part. The organic functional element manufacturing apparatus which comprises these.

According to a twelfth aspect of the present invention, there is provided a moving table having a movable means provided with a substrate installation part, and a means for spraying a liquid of a dry solvent in the form of a mist, the spraying position of which coincides with the moving table. And a spraying device of which the spraying position coincides with the moving table, and the spraying means and the spraying means are sprayed with respect to the moving direction of the moving table. It is the organic functional element manufacturing apparatus installed so that it may become the order of a position and the spraying position of the said gas spraying apparatus.

The invention according to claim 13 is an organic function comprising: a sealable chamber; a means for replacing the atmosphere in the chamber with an inert gas; and a means for spraying a liquid of a dry solvent in a mist form. This is a conductive element manufacturing apparatus.

The invention according to claim 14 is the organic functional element manufacturing apparatus according to claim 13, further comprising means for heating the substrate.

The invention according to claim 15 is the organic functional element manufacturing apparatus according to claim 14, wherein the moving table having a substrate installation portion and having movable means, and the spray position are on the moving table. The means for spraying and the means for heating the substrate, the heating position of which coincides with the moving table, and the means for spraying and the means for heating move the moving table. It is an organic functional element manufacturing apparatus characterized in that the spraying position of the spraying means and the heating position of the heating means are arranged in this order with respect to the direction.

The invention according to claim 16 is the organic functional element manufacturing apparatus according to claim 14 or 15, wherein the means for heating the substrate is heating by an infrared heater.

The first solvent (hereinafter referred to as residual solvent) contained in the organic functional layer patterned by the printing method is used as the second solvent (hereinafter referred to as dry solvent) by using the method described in claim 1. ) Substitution has occurred, and the organic functional layer can be dried without being deteriorated by heating or the like. In addition, by using a fluorinated solvent as the drying solvent, especially a fluorinated solvent composed of molecules having 5 or more fluorine atoms, the wettability is good and the organic functional material can be dried without causing deterioration. It was. In particular, when the surface tension of the dry solvent was 25 mN / m or less, the penetration of the dry solvent into the organic functional layer was increased, and a high drying ability could be obtained. As a result, the residual solvent can be easily removed without damaging the organic functional layer. Furthermore, by using a dry solvent that satisfies the conditions of claim 6, it is possible to manufacture with reduced influence on the organic functional layer. By using the manufacturing apparatus as described in claims 10 to 16 by the manufacturing method as described above, a high-quality organic functional element can be manufactured as a result.

Further, as described in claim 3, by cooling to a temperature not lower than 10 ° C. and not higher than 25 ° C., the coating film on the substrate is brought into contact with the heated and gasified atmosphere of the second solvent. In addition, the dry solvent can be condensed on the substrate and penetrated into the organic functional layer, and the residual solvent can be efficiently removed. Moreover, the said manufacturing method became realizable by using the organic functional element manufacturing apparatus of Claim 11.

In addition, as described in claim 4, by spraying a mist-like dry solvent and replacing the residual solvent with a solvent, the dry solvent is heated, or the organic functional layer is immersed in the liquid of the dry solvent. Thus, a washing and drying process and a manufacturing method with less influence on the organic functional layer can be realized.

Further, according to the invention described in claim 5, after removing the residual solvent by the dry solvent, particularly when the substrate is subjected to heat treatment, by performing the treatment in a sealed space filled with an inert gas atmosphere, oxygen or the like is used. Damage to the organic functional layer could be avoided. The present invention is particularly effective when forming a plurality of organic functional layers.

In addition, according to the invention described in claim 9, by manufacturing an organic functional element using the method for manufacturing an organic functional layer of the present invention, damage due to a drying process, reduction in luminance and light emission lifetime due to a residual solvent, etc. It was possible to manufacture high-quality organic functional elements with a reduced amount.

Furthermore, as an invention of an apparatus that enables the method for producing an organic functional layer of the present invention, the organic functional element production apparatus according to claim 10 is an ultrathin apparatus for cleaning and replacing a coated substrate holding a dry solvent. An organic functional layer substrate that efficiently replaces the residual solvent by being a manufacturing apparatus equipped with a sonic tank, a rinse layer that removes the substituted residual solvent from the substrate, and a steam tank for drying the substrate. Can be dried.

Further, in the invention described in claim 11, the manufacturing method as described in claim 3 can be realized by providing the steam tank provided with the means for generating the vapor of the dry solvent and the substrate cooling device. According to the present invention, since the residual solvent and the dry solvent can be replaced and dried in one place, the residual solvent and the dry solvent can be efficiently replaced. Further, since the immersion is not performed, adhesion of impurities can be avoided. .

In the invention according to claim 12, by providing the moving table, it is possible to continuously manufacture the organic functional layer, and to improve the productivity of the organic functional element.

Further, in the inventions according to claims 13 and 14, by using a manufacturing apparatus provided with means for spraying a mist-like dry solvent in the chamber, the influence of the outside air can be avoided, and further due to oxygen or the like during heating. Damage could be avoided. By providing the means for heating in the inert gas, the drying process can be quickly processed, and further, the surface of the organic functional layer can be heat-treated.

Further, in the invention according to claim 15, it is possible to continuously manufacture organic functional elements by further arranging the manufacturing apparatus according to the previous paragraph on the moving table in the order along the manufacturing process. became. Further, according to the invention of claim 16, since an infrared heater is used as means for heating the substrate, heating can be performed without directly contacting the substrate, and the substrate can be provided independently of the moving table. The time required for each process was shortened, and an efficient organic functional element could be manufactured.

Hereinafter, embodiments of the present invention will be described in detail.

The charge transport layer or charge transfer layer 103a in FIG. 1, the organic light emitting layer or active layer 103b, and the organic semiconductor layer 205 in FIG. 2 correspond to the organic functional layer in the present invention. As described in “Background Art”, the printing method is excellent for fine patterning of the organic functional layer. In addition, since it is an important point for the present invention how to remove the solvent from the organic functional layer that is weak against oxygen and water and to dry it in the production of the organic functional element, printing common to the production of each functional element First, the process from the formation of the organic functional layer using the method to the drying will be described.

(Deposition method of organic functional layer)
A method for forming an organic functional layer according to the present invention will be described with reference to FIG.
FIG. 3 is a schematic view of a relief printing apparatus used for pattern printing of a coating liquid (ink) made of an organic functional material on a substrate by a relief printing method. The manufacturing apparatus includes an ink tank 301, an ink chamber 302, an anilox roll 303, and a plate cylinder 305 on which a relief plate 306 provided with projections is mounted. The ink tank 301 contains ink of an organic functional material dissolved or dispersed in a solvent, and the ink is supplied from the ink tank 301 to the ink chamber 302. The anix roll 303 is rotatably supported in contact with the ink supply part of the ink chamber 302.

As the anix roll 303 rotates, the ink layer 304 supplied to the anix roll surface is formed to a uniform film thickness. At that time, although not shown, excess ink may be removed with a doctor knife. This ink layer is transferred to the convex portion of the relief plate 306 mounted on the plate cylinder 305 that is driven to rotate in the vicinity of the anix roll. On the flat table 308, the substrate to be printed 307 is conveyed to a printing position by the convex portion of the plate 306 by a conveying means (not shown). The ink on the convex portion of the relief plate 306 is printed on the substrate 307 to be printed.

A photosensitive resin plate is used for the relief plate. The photosensitive resin plate includes a solvent development type in which the developer used when developing the exposed resin plate is an organic solvent and a water development type in which the developer is water. The solvent development type is resistant to water-based inks, and the water development type is resistant to organic solvent-based inks. Therefore, it is necessary to select appropriately according to the physical properties of the ink to be printed.

When forming an organic functional layer on a substrate by a relief printing method using a coating liquid (ink) in which an organic functional material is dissolved or dispersed in a solvent, it is used to convert the organic functional material into a coating liquid. A high boiling point solvent is used as the solvent. This is because when a low boiling point solvent is used, the ink that is the coating liquid is gradually dried in a process in which the ink chamber that is the ink supply body is supplied to the anilox roll and transferred from the anilox roll to the relief printing plate. When transferring the ink on the convex portions of the relief plate to the substrate, there arises a problem that the coating liquid is not transferred to the substrate due to the drying of the coating liquid. That is, in the printing process, a high boiling point solvent is used as a solvent for the coating liquid in order to prevent transfer failure due to drying of the coating liquid.

In addition, even when an organic functional layer is formed on a substrate by using an intaglio offset printing method or a relief reversal offset printing method, a high-boiling solvent is used as a solvent used to liquefy the organic functional material. It is done. The intaglio offset printing method comprises a step of supplying ink from an ink supply to an intaglio, a step of transferring ink from the intaglio to an elastic silicone blanket, and a step of transferring an ink pattern on the blanket onto a substrate. However, when a low boiling point solvent is used, the coating liquid dries during the printing process, which causes a problem that ink is not transferred from the blanket onto the substrate.

The letterpress reversal offset printing method is a method in which ink is supplied onto the blanket from the ink supply body, and the ink on the blanket is transferred onto the convex part of the removal plate by using the removal plate having the convex part pattern to transfer the ink on the blanket. It consists of a process of forming a pattern and a process of transferring the ink pattern on the blanket onto the substrate, but when a low-boiling solvent is used, the coating liquid dries during the printing process. The problem arises that the ink is not transferred from the blanket onto the substrate.

In this way, when a coating liquid containing an organic functional material is patterned on a substrate using a printing method to form an organic functional layer, a high boiling point is used to prevent drying of the coating liquid during the printing process. It is essential to use a solvent.

Even when the organic functional layer is formed on the substrate by the ink jet printing method, it is not necessary to consider drying of the coating liquid during the printing process, but a high boiling point solvent is used. In the inkjet printing method, an ink pattern is formed by dropping a coating liquid onto an area partitioned by a bank (partition) from an inkjet nozzle in an inkjet head. In the inkjet method, when the organic functional layer is formed using a low boiling point solvent, the film thickness of the organic functional layer is greatly changed in the bank due to the rapid drying of the coating liquid dropped on the substrate. There arises a problem that an organic functional layer having a uniform film thickness cannot be obtained. Therefore, it is necessary to use a high boiling point solvent in the inkjet method as a printing method.

(Cleaning and drying method of organic functional layer)
The organic functional layer cleaning and drying method of the organic functional layer according to the present invention will be described.

As described above, when the organic functional layer is formed by a printing method, it is necessary to use a high boiling point solvent. For this reason, it takes a long time to remove the solvent from the coating film of the organic functional layer in the heat drying, Moreover, it cannot necessarily be removed sufficiently. Furthermore, when the organic functional layer is exposed to a high temperature for a long time, the organic functional element is damaged or deteriorated, and consequently the characteristics of the organic functional element are deteriorated.

Therefore, in the present invention, in order to sufficiently remove the coating solution solvent without deteriorating the organic functional layer, the step of replacing the residual solvent with the dry solvent and the step of removing the dry solvent from the organic functional layer are performed. The coating film was dried to form an organic functional layer. Specifically, a method of immersing the substrate in a dry solvent, washing and rinsing, removing the dry solvent by pulling up, a method of replacing the residual solvent by adsorbing the dry solvent vapor to the cooled substrate, and a substrate with the dry solvent There is a method of spraying. Details will be described together with the manufacturing apparatus of the present invention described later.

The dry solvent used in the present invention must be a solvent that can be mixed with the residual solvent in order to replace the solvent, and must be an inert solvent that does not dissolve in the organic functional layer.

By the way, many of the materials used as the organic functional material are π-electron materials having an aromatic ring structure. Such compounds are easily soluble in aromatic solvents such as toluene and xylene. In some cases, π-electron-based materials are mixed with ionic substituents or dopants, and in that case, they are easily dissolved in a highly polar solvent such as alcohol. Although a solvent containing a large amount of fluorine atoms exhibits very low solubility in the above-mentioned film made of an organic functional material, it has a feature that it can be mixed with the above-mentioned solvents such as aromatic solvents and alcohols. . Therefore, the fluorine-based solvent satisfies the above-mentioned conditions as a dry solvent, and therefore, without dissolving the organic functional layer, the residual solvent of the coating liquid (ink) of the organic functional material contained therein is removed. It becomes possible to substitute with a dry solvent. Furthermore, a solvent containing a large amount of fluorine atoms has higher volatility and better wettability than a hydrocarbon solvent having the same molecular weight.

In order to efficiently replace the dry solvent and the residual solvent in the organic functional layer, the surface tension is preferably low in order to allow the dry solvent to penetrate into the organic functional layer. Specifically, the surface tension of the dry solvent Is preferably 25 mN / m or less.

In addition, the vapor pressure of the dry solvent needs to be higher than the vapor pressure of the coating solution at room temperature in order to quickly remove the dry solvent on the substrate after replacing the solvent in the organic functional layer. The higher the pressure, the better. Specifically, the vapor pressure in the drying step of the dry solvent is preferably at least 5000 Pa or more. If the volatility of the drying solvent is sufficiently high, there is no need to create a special drying device such as a vacuum dryer or an inert gas atmosphere, which can reduce the cost of manufacturing equipment and shorten manufacturing time. Become.

Moreover, it is necessary to have the property of replacing the residual solvent in the organic functional layer and the property of not dissolving or peeling the dried thin film of the organic functional material. Specifically, since it is not preferable that the organic functional layer film dissolves and peels when the organic functional layer substrate is immersed in a dry solvent, the organic functional layer immediately after the immersion is used as a reference for preventing dissolution and peeling. The change rate of the surface roughness Ra of the organic functional layer 24 hours after immersion with respect to the surface roughness Ra (JIS B0601-1994) was less than 1%, and similarly dissolved in the second solvent after 24 hours. The weight of the organic functional layer is preferably less than 0.1% of the weight of the organic functional layer after the drying step.

As such a dry solvent, a compound containing 5 or more fluorine atoms in one molecule can be preferably used. Specifically, fluoro ethers such as methyl nonafluorobutyl ether, ethyl nonafluorobutyl ether, tridecafluorohexyl methyl ether, 1,1,2,2,3,3,4-heptafluorocyclopentane, 1,1, Fluoroalkanes such as 1,3,3-pentafluorobutane and octafluoro-2-butene, as well as fluoroalkenes, hexafluorobenzene, pentafluorobenzene, octafluorotoluene, 1,3-bis (trifluoromethyl) benzene, etc. And fluoroalcohols such as 1,1,1,3,3,3-hexafluoro-2-propanol can be preferably used. That is, in the present invention, ethers, alkanes, alkenes, aryls, alcohols and the like containing 5 or more fluoro groups (fluorine groups) as substituents in one molecule are preferably used as a dry solvent. be able to.

(Organic functional layer manufacturing equipment)
Next, a specific example of a manufacturing apparatus using the above-described organic functional layer manufacturing method of the present invention will be described with reference to the drawings. Each apparatus illustrated is an example of the form of the manufacturing apparatus of the present invention, and is not limited thereto.

First, a manufacturing apparatus having a configuration as shown in FIG. 4 will be described. 4 includes a substrate holder 401 for fixing a substrate, an ultrasonic layer 402 filled with a dry solvent, a rinse layer 404 filled with a dry solvent, a cooling device 407, and means for generating a vapor of the dry solvent. A steam tank 408 is provided. The drying process using the apparatus of FIG. 4 is as follows.

First, a substrate coated with an organic functional layer is placed on a substrate holder 401 and cleaned in an ultrasonic bath 402 filled with a dry solvent. The substrate may be subjected to preliminary drying such as heating in advance. In order to obtain a uniform cleaning / drying effect, the substrate holder 401 may be swung in the ultrasonic bath 402. The output and frequency of ultrasonic waves from the ultrasonic transmitter 403 and the temperature of the dry solvent in the ultrasonic tank 402 are arbitrary. Moreover, although the number of ultrasonic tanks is one in FIG. 4, the number is not limited. When the organic functional layer applied on the substrate is easily peeled off, the ultrasonic bath is not necessary.

Next, the substrate holder 401 is immersed in a rinse tank 404 filled with a dry solvent. The dry solvent in the rinse tank 404 may be stirred, or the substrate holder 401 may be swung in the rinse tank 404. It is preferable that the temperature of the dry solvent in the rinse tank 404 is low. However, if it is too low, condensation of liquid other than a dry solvent such as water may occur on the surface of the substrate when the substrate holder 401 is lifted from the rinse tank 404. . By lowering the temperature of the drying solvent in the rinsing tank 404, the substrate temperature rise in the next steam tank is suppressed, and the efficiency of cleaning and drying is improved. The time for immersing the substrate holder in the rinsing tank 404 is arbitrary. At this time, the ultrasonic frequency is preferably a high frequency, specifically 500 kHz to 3 MHz. By using high frequency ultrasonic waves, it becomes difficult to damage the organic functional layer provided on the substrate.

Next, the substrate holder 401 is installed in the steam tank 405. The steam tank 405 is provided with a heater 406 at the bottom, and the heater is immersed in the dry solvent 408. The dry solvent is heated by a heater, and the upper part of the steam tank 405 is filled with the steam 409. This steam is cooled by the cooling unit 407 installed at the upper part of the steam tank 405 and flows down to the lower part. The vapor | steam of a dry solvent adsorb | sucks to the board | substrate surface in the board | substrate holder 401, is cooled by the board | substrate, and is condensed, and flows down to the vapor | steam tank 405 lower part. At that time, the residual solvent in the organic functional layer also flows down together with the dry solvent. When the substrate temperature becomes the same as the boiling point of the dry solvent, condensation on the substrate surface does not occur, so the substrate holder 401 is pulled up from the steam tank 405. The substrate holder that has been pulled up may be cooled by immersing it in the rinsing tank 404 or by applying cold air, and then moved back into the steam tank 405 for cleaning and drying.

When the next layer is further stacked on the substrate dried by the above method, the sealed space can be moved to the next step, and the stack can be performed without any dust or other deposits on the substrate. . For example, after the organic light emitting layer of the organic EL element is dried, the substrate is moved in a sealed space and transferred to a vapor deposition apparatus to form a cathode layer, thereby preventing a short circuit or a dark spot from being formed due to deposits. I can do it.

The manufacturing apparatus of the form shown in FIG. 5 has a dry solvent vapor tank 405 similarly to the apparatus of FIG. 4, and uses this to replace the solvent from the organic functional layer to remove the residual solvent. The apparatus of FIG. 5 has a substrate cooler 502. When the dry solvent vapor generated from the vapor tank 405 heated by the heater 406 comes into contact with the substrate on which the organic functional layer coating film is formed, the temperature of the substrate surface is cooled below the dew point of the dry solvent by the substrate cooler. Therefore, since the dry solvent is condensed and adsorbed on the surface of the substrate, the solvent substitution with the residence solvent in the organic functional layer can be performed very efficiently. By placing the substrate in a vertical position, the condensed solvent will drop into the vapor tank and can be reused as a dry solvent. Further, the substrate cooler 502 is supported by a tool (not shown), and can be taken in and out of the steam tank 405 at an arbitrary timing.

The substrate cooler 502 only needs to be able to cool the substrate 501 appropriately. A heat exchanger capable of flowing a fluid such as water or air, a Peltier element, a metal block having a large heat capacity, or the like can be used. I can do it. The cooling temperature of the substrate 501 may be a temperature that is lower than the boiling point of the dry solvent. However, if the temperature is too low, water such as water on the substrate surface when the substrate cooler 410 and the substrate 501 are taken out from the vapor tank 405 is used. Condensation of liquids other than dry solvents may occur. Therefore, it is preferable that the temperature of the substrate cooler 410 is not higher than the dew point of the dry solvent and is not lower than 10 ° C and not lower than 25 ° C. However, since the dew point of water is low in an environment where the inside of the apparatus is purged with nitrogen and filled with dry nitrogen or the like, the temperature may be further lowered.

Further, the temperature of the vapor tank 405 for generating the dry solvent vapor 408 needs to be heated at least to the extent that the dry solvent vapor is generated, but the residual solvent removed from the organic functional layer coating film is applied to the substrate. In order to prevent re-adsorption, it is preferably below the boiling point of the residual solvent.

If the apparatus having the configuration as shown in FIG. 5 is used as described above, the substrate is cooled by the substrate cooler 502 in the vapor tank 405, thereby avoiding the phenomenon that the dew condensation of the dry solvent does not occur due to the substrate temperature rise. Exposure time is arbitrary. Moreover, since it does not need to put into a rinse tank, the high-boiling-point solvent contained in the dry solvent in a rinse tank, and reattachment of dust and dust are avoided. Further, since rapid cooling in the rinsing tank is not performed, the possibility that the film quality of the organic functional layer changes due to a rapid temperature change can be avoided.

In the method of the present invention, as shown in FIGS. 6 to 9, the dry solvent can be made into a mist and brought into contact with the substrate. According to this method, it is not necessary to move and immerse the substrate in the solution, or to liquefy the dry solvent vapor again by cooling or the like, and processing at room temperature is possible.

In the apparatus of the form shown in FIG. 6, the dry solvent 609 that has been atomized by the ultrasonic atomizer 606 in the mist generation tank 605 is sprayed onto the substrate 501 coated with the organic functional layer, and its droplets. Residual solvent is removed when dripping. The air blower 604 may be used so that the mist-like dry solvent efficiently hits the substrate surface, and the air inlet 602 and the air outlet 603 may be provided. Further, the dry solvent dripped from the substrate may be collected in the collection tank 607. By performing spray spraying, it is not necessary to apply heat to the dry solvent, and it is not necessary to cover the apparatus with a heat insulating material. Further, since the substrate is not heated, there is no fear of thermal degradation.

In the apparatus as shown in FIG. 7, a substrate 501 coated with an organic functional layer is placed on a moving table 703, and a dry solvent spray device 701 placed on the moving table mist-like dry solvent 609. To replace the solvent. According to the apparatus of FIG. 7, it is possible to perform the drying process continuously by placing the substrate 501 on the moving table 703 having an endless belt shape and moving the substrate instead of every batch, for example. It becomes. In FIG. 7, the substrate is arranged horizontally, but the drying solvent may flow down quickly by being inclined or arranged vertically. The dry solvent dripped from the substrate can be recovered and reused by a solvent regenerator (not shown) as appropriate.

Examples of the spray 701 include a two-fluid type nozzle. By applying an appropriate amount of a cleaning and drying solvent to the substrate 501 coated with the organic functional layer with an appropriate pressure, the drying solvent is applied to the coating film. There is no particular limitation as long as it can permeate and replace the residual solvent. Accordingly, the type of spray and the discharge conditions may be selected as appropriate in accordance with the type of organic functional layer, adhesion to the substrate, and the properties of the cleaning and drying solvent.

Further, by installing the air blower 702 after spraying the dry solvent, the residual solvent can be removed together with the cleaning dry solvent 609 by the gas blown from the air blower. In addition, when discharging a dry solvent from the nozzle of a spray apparatus, you may give an ultrasonic wave to a dry solvent. By applying ultrasonic waves to the cleaning / drying solvent, a higher cleaning / drying effect can be obtained.

In the apparatus of the form as shown in FIG. 8, it is possible to perform cleaning and drying of the substrate 501 coated with the organic functional layer in an atmosphere substituted with an inert gas such as nitrogen. By performing cleaning and drying in an inert gas atmosphere, it is possible to avoid deterioration caused by oxygen or water contained in the atmosphere adsorbing or reacting with the organic functional layer. In addition, by installing a heating device such as a hot plate in the substrate holder 802, the heat treatment can be performed after the residual solvent is removed with the dry solvent.

As will be described later, in the manufacturing process of an organic functional layer such as an organic EL element or an organic solar battery, the organic functional layer is often formed to have a multilayer structure. In this case, in the lamination process of each layer, mixing at the interface with the existing layer corresponding to the surface to be formed becomes a problem. Even when the existing layer is completely dried, normal drying alone is not sufficient if there is solubility due to the material of each layer. Therefore, the material of the outermost layer causes a cross-linking reaction to insolubilize, or a reaction occurs at the interface between the outermost layer and the layer below it to improve adhesion, so that it is newly added next. Methods have been taken to prevent dissolution of the layer by ink and avoid mixing at the layer interface. For this reason, it is generally performed to heat-treat the organic functional layer.

However, as described in the problem to be solved, the organic functional material easily reacts with oxygen and the like, and particularly when heated, the reactivity increases. It is preferable to carry out in an inert gas atmosphere such as nitrogen. Therefore, as shown in FIG. 8 or FIG. 9 to be described later, the above-mentioned problem is caused by making the inside of the apparatus a sealed space and further performing from the solvent removal to the heat treatment in the same vacuum or in an inert atmosphere. can be solved.

Moreover, you may have the apparatus for cooling after heat processing, In that case, a thing like the board | substrate cooling apparatus described by description of the apparatus of FIG. 5 can be used. In this case, it is also possible to use infrared rays as the heating device and heat-treat it by attaching it to the front surface of the substrate so that the heating device does not become an obstacle.

In the apparatus as shown in FIG. 9, in order to continuously process the substrate, each apparatus is installed in the order of processing steps after the substrate is installed in the apparatus. The substrate 501 coated with the organic functional layer installed on the substrate holder 802 in the pre-treatment substrate box 902 proceeds along the substrate transport rail 901 and is first left by the mist-like dry solvent discharged from the spray device 701. The solvent is replaced and washed and dried. Next, heat treatment is performed by the heating device 903.

As the heating device 903 used for the heat treatment, a known device can be used, but it is preferable to perform the heat treatment using an infrared device that can be remotely heated. This is because the substrate processing can be continuously performed with a simple configuration because it can be installed at a place away from the transport rail. As the infrared ray to be used, either near infrared ray or far infrared ray may be used, but it is preferable to irradiate the far infrared ray from the front side of the substrate 501 in order to efficiently heat the thin substrate coated with the organic functional layer. In addition, when a material that easily reflects far-infrared rays such as aluminum is used as a material for the substrate holder surface, the substrate can be efficiently heated because infrared rays transmitted through the substrate are also irradiated from the back surface of the substrate.

(Element structure of organic EL element and organic solar cell)
Next, an organic EL element and an organic solar cell using the drying method will be described with reference to FIG.

The substrate 101 used in the present invention is not limited as long as it is light-transmitting and has a certain level of strength. Specifically, a glass substrate or a plastic film or sheet can be used. If a thin glass substrate having a thickness of 0.2 to 1 mm is used, a thin organic EL element or an organic solar cell having a very high barrier property can be produced.

The transparent conductive layer 102 is not particularly limited as long as it is a conductive material capable of forming a transparent or translucent electrode. Specifically, indium and tin composite oxide (hereinafter referred to as ITO), indium and zinc composite oxide (hereinafter referred to as IZO), tin oxide, zinc oxide, indium oxide, zinc aluminum composite oxide, and the like are included as oxides. However, ITO can be preferably used because of its low resistance, solvent resistance, transparency, and the like, and can be formed on the light-transmitting substrate 101 by vapor deposition or sputtering. Alternatively, a precursor such as indium octylate or indium acetone can be applied on a substrate and then formed by an application pyrolysis method in which an oxide is formed by thermal decomposition. Alternatively, a metal in which a metal such as aluminum, gold, or silver is vapor-deposited in a translucent state can be used. Alternatively, an organic semiconductor such as polyaniline can also be used.

The transparent conductive layer 102 may be patterned by etching as necessary, or may be activated by UV treatment, plasma treatment, or the like.

The organic functional layer 103 in the present invention may be a single layer or a stack of a plurality of functional layers. In the case of an organic EL element, it is necessary to provide at least an organic light emitting layer between the anode and the cathode. In addition, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, etc. as functional layers The charge transport layer can be provided, and its configuration is arbitrary.

In addition, in the case of organic solar cells, it is necessary to have a layer between the anode and cathode electrodes in which a plurality of materials called active layers coexist in a state where the interface called multiheterojunction is intertwined in a complicated manner. In addition, a charge transfer layer for taking out the charges generated there can be provided as an organic functional layer. Although the thickness of the organic functional layer is arbitrary, if it is too thin, a short circuit is likely to occur, and if it is too thick, the resistance of the entire device increases. Therefore, the total film thickness is preferably 50 to 1000 nm.

The material used for the charge transport layer 103a mainly provided adjacent to the transparent conductive layer 102 may be any material generally used as a hole transport material, such as copper phthalocyanine and its derivatives, 1,1-bis ( 4-di-p-tolylaminophenyl) cyclohexane, N, N′-diphenyl-N, N′-bis (3-methylphenyl) -1,1′-biphenyl-4,4′-diamine, N, N ′ Low molecular weight compounds such as aromatic amines such as di (1-naphthyl) -N, N′-diphenyl-1,1′-biphenyl-4,4′-diamine can also be used, but polyaniline derivatives and polythiophene derivatives From the viewpoint of film-forming properties, polymer materials such as polyvinyl carbazole (PVK) derivatives, mixtures of poly (3,4-ethylenedioxythiophene) and polystyrenesulfonic acid, etc. Masui. In addition, polyamines such as polyparaphenylene (PPP), polyarylene vinylenes such as polyphenylene vinylene (PPV), conductive polymers such as polyarylene vinylene (PPV), or polymers such as polystyrene (PS), arylamines, carbazole derivatives, aryl A mixture of sulfides, thiophene derivatives, phthalocyanine-derived low molecular charge transporting materials, and the like may be used.

As a light emitter used for the organic light emitting layer 103b in the organic EL element, coumarin-based, perylene-based, pyrene-based, anthrone-based, porphyrene-based, quinacridone-based, N, N′-dialkyl-substituted quinacridone-based, naphthalimide-based, N, N Low-molecular luminescent dyes such as' -diaryl-substituted pyrrolopyrrole, iridium complex, platinum complex, and europium complex are dissolved or copolymerized in polymers such as polystyrene, polymethylmethacrylate, and polyvinylcarbazole. And polymer light emitters such as polyarylene, polyarylene vinylene, and polyfluorene can be used.

In addition, a material called an interlayer that increases adhesion to the charge transport layer 103a by heating may be sandwiched between the organic light emitting layer 103b and the charge transport layer 103a in the organic EL element. It is known that this interlayer increases the light emission efficiency of the organic light emitting layer 103b and extends the driving life. Such materials include poly (2,7- (9,9-di-octylfluorolene))-alt- (1,4-phenylene-((4-sec-butylphenyl) imino) -1,4. -Phenylene)) (TFB).

The material used for the active layer 103b in the organic solar cell may be a p-type / n-type semiconductor material that causes charge separation when irradiated with light. Specifically, a polythiophene derivative or a polyphenylene vinylene derivative may be used as the p-type semiconductor. Examples of n-type semiconductors include fullerene derivatives.

In the case of low molecular weight, these materials may be formed by vapor deposition, but toluene, xylene, acetone, anisole, methylanisole, dimethylanisole, ethyl benzoate, methylbenzoate, mesitylene, tetralin, amylbenzene , Methyl ethyl ketone, Methyl isobutyl ketone, Cyclohexanone, Methanol, Ethanol, Isopropyl alcohol, Ethyl acetate, Butyl acetate, Water, etc. A single or mixed solvent used as a coating solution, spin coating method, curtain coating method, bar coating The film may be formed by a coating method such as a coating method, a wire coating method, a slit coating method, a letterpress printing method (flexographic printing method), an intaglio offset printing method, a letterpress reverse printing method, an ink jet printing method, an intaglio printing method. Possible A.

However, in order to display the organic EL element in full color, it is necessary to pattern the organic light emitting layer into three colors of R (red), G (green), and B (blue). Thus, when patterning an organic light emitting layer, it is preferable to use a printing method such as a relief printing method (flexographic printing method), an intaglio offset printing method, a relief printing reverse offset printing method, an ink jet printing method, and an intaglio printing method. In addition, organic light-emitting layers having different emission colors can be patterned for each pixel. In the organic EL element, the charge transport layer such as a hole transport layer or an electron transport layer is preferably patterned for each pixel in order to prevent current leakage to adjacent pixels. Also in this case, a printing method such as a relief printing method (flexographic printing method), an intaglio offset printing method, a relief printing reverse offset printing method, an ink jet printing method, and an intaglio printing method can be suitably used.

In order to obtain high efficiency and electromotive force in organic solar cells, it is necessary to pattern the active layer and the charge transfer layer. The letterpress printing method (flexographic printing method), the intaglio offset printing method, the letterpress reverse printing method A printing method such as an inkjet printing method or an intaglio printing method can be suitably used. Therefore, the production method of the present invention is effective.

The organic functional layer is formed by using the organic functional layer forming method and the drying method described above. In addition to forming all the organic functional layers by the above method, it is also conceivable to form each layer in combination with other wet process and dry process.

Next, an electrode layer 104 composed of a cathode is formed on the organic functional layer 103. As the electrode layer, a single metal such as Mg, Al, Yb, Ba, or Ca is used, or a compound such as Li or LiF is sandwiched by about 1 nm at the interface in contact with the light emitting medium material. Cu can be laminated and used. Alternatively, in order to achieve both electron injection efficiency and stability, an alloy system of a metal having a low work function and a stable metal, for example, an alloy such as MgAg, AlLi, or CuLi can be used. As a method for forming the cathode, a resistance heating vapor deposition method, an electron beam method, or a sputtering method can be used depending on the material. The thickness of the electrode layer is desirably about 10 nm to 1000 nm.

In order to improve the adhesion between the layers, the substrate may be heat-treated before, after, or before and after the electrode layer 104 is formed.

Finally, in order to protect these organic functional laminates from external oxygen and moisture, a glass cap and an adhesive are hermetically sealed to obtain an organic EL element. Moreover, when a translucent board | substrate has flexibility, sealing sealing is performed using a sealing agent and a flexible film.

(Element structure of organic thin film transistor)
The organic thin film transistor according to the present invention will be described with reference to FIG.

In the top-gate thin film transistor of FIG. 2, an inorganic insulating layer 202 is formed on a substrate 201, a source electrode 203 and a drain electrode 204 are formed on the inorganic insulating layer 202, and an organic semiconductor layer 205 is formed. A gate insulating layer 206 is formed over the organic semiconductor layer 205, and a gate electrode 207 is formed over the gate insulating layer 206.

In the top-gate thin film transistor, a known material such as glass, metal, or plastic can be used for the substrate 201. In particular, a plastic material can be suitably used. Examples of the plastic material include polyethylene terephthalate, polyethylene naphthalate, polyether sulfone, cycloolefin polymer, polyimide, nylon, aramid, polycarbonate, polymethyl methacrylate, polyvinyl chloride, and triacetyl. A film or sheet of cellulose or the like can be used. Of these, heat-resistant polyethylene naphthalate, polyethersulfone, cycloolefin polymer, polyimide and the like can be preferably used. Moreover, what improved the heat resistance by adding an inorganic filler to the said resin can also be used conveniently.

An inorganic insulating layer 202 is formed on the substrate 201 as necessary. As the inorganic insulating layer 202, various kinds of oxides such as SiO2, Al2O3, SiON, and Ta2O5, oxynitrides, and the like can be used. As a formation method, a vacuum deposition layer, a sputtering method, a CVD method, or the like can be used.

Next, the source electrode 203 and the drain electrode 204 are formed over the inorganic insulating layer 202. Examples of the source and drain electrode materials include metals such as gold, silver, copper, nickel, platinum, palladium, and rhodium. These materials can also be formed by resistance heating vapor deposition, electron beam, or sputtering. However, these metal nanoparticles can be dissolved or dispersed in water or alcohol as a solvent to form a film by printing. Can be a membrane. Here, the metal nanoparticles mean metal particles having an average particle size of less than 1 μm.

Next, the organic semiconductor layer 205 is provided over the inorganic insulating layer 202, the source electrode 203, and the drain electrode 204. As the organic semiconductor layer forming material, polythiophene derivatives, polyphenylene vinylene derivatives, polythienylene vinylene derivatives, polyallylamine derivatives, polyacetylene derivatives, acene derivatives, oligothiophene derivatives, etc. can be used, and these are dissolved or dispersed in a solvent. Using ink (coating solution), coating methods such as spin coating, curtain coating, bar coating, wire coating, slit coating, letterpress printing (flexographic printing), intaglio offset printing, letterpress inversion offset It is possible to form a film by a printing method such as a printing method, an ink jet printing method, or an intaglio printing method.

In an organic transistor, at least one of a source electrode, a drain electrode, a gate electrode, and an organic semiconductor layer is a relief printing method (flexographic printing method), an intaglio offset printing method, a relief inversion offset printing method, an ink jet printing method, an intaglio printing method, and the like. Although a film is preferably formed by a printing method, it is not necessary to form all components by the printing method.

Next, the gate insulating layer 206 is provided over the organic semiconductor layer 205. As the gate insulating layer 206, an organic insulating film that can be easily formed can be suitably used. For example, polyvinylphenol can be used. In the case of polyvinyl phenol, for example, it is dissolved in isopropyl alcohol and formed on the organic semiconductor layer by spin coating.

Next, the gate electrode 27 is provided over the gate insulating layer 206. As the gate electrode 207, a mask vapor deposition may be used in addition to a printing method such as a relief printing method, an intaglio printing method, a screen printing method, a gravure printing method, a flexographic printing method, and an offset printing method. If the gate electrode is formed by a printing method, an ink containing a conductive material such as gold, silver, copper, nickel, platinum, palladium, or rhodium can be used. Further, if the gate electrode 207 is formed by a vacuum deposition method, Al, gold, platinum, palladium, rhodium, or the like can be used.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

<Examples of organic EL elements>
A glass substrate with ITO was prepared, and the ITO was etched into a predetermined pattern. Next, a liquid in which a mixture of poly (3,4-ethylenedioxythiophene) and polystyrenesulfonic acid is dispersed in water as an electron transporting layer coating solution on the etched transparent conductive layer by a letterpress printing method. It was applied in a pattern on the substrate. This substrate was dried at 200 ° C. for 3 minutes in the air. The thickness after drying was 50 nm.

Further, poly (2- (2-ethylhexyloxymethoxy) -5-methoxy-1,4-phenylenevinylene) (glass transition temperature 196 ° C.) which is a polyarylene vinylene polymer light emitting material as a coating solution for the light emitting layer. Was dissolved in a mixed solvent of 50% toluene and 50% diethylbenzene, and applied onto the substrate in a pattern by a relief printing method.

Furthermore, after performing the drying process described in Examples 1 to 4 and Comparative Example 1 on this organic functional layer substrate, lithium and aluminum were provided by 0.5 nm and 200 nm, respectively, by vacuum deposition to obtain an organic EL element. It was. Hereinafter, the contents and production results of the drying step will be mainly described for each example.

Example 1
In the drying step, the organic functional layer substrate was placed on a substrate holder, and an organic EL element was produced using the apparatus shown in FIG. Ethyl nonafluorobutyl ether was used as a dry solvent. The ultrasonic treatment was carried out for 5 min at 3 frequencies of 26 kHz, 45 kHz and 100 kHz in a dry solvent at 25 ° C., immersed in a dry solvent at 15 ° C. for 10 min in a rinse bath, and exposed to steam for 3 min in a steam bath. Furthermore, the process of the rinse tank and the steam tank was repeated 3 times.

When a voltage of 8 V was applied to the obtained organic EL element, it showed patterned luminescence of 100 cd / m2. Further, when the luminance half-life at the time of constant current driving was measured at an initial luminance of 100 cd / m 2, the luminance half-life was 3000 hr.

After forming the organic functional layer substrate in the same step and finishing the drying step, the concentration of each solvent in the organic functional element dried by measuring the concentration of each solvent in the organic functional layer with GC-MS As a result, the concentrations of toluene, diethylbenzene, and ethyl nonafluorobutyl ether were <0.1 ppm (below the detection limit).

(Example 2)
Next, in the drying process, the drying solvent was changed to tridecafluorohexyl methyl ether, and ultrasonic treatment was not performed, and immersion in a rinse bath at 15 ° C. for 10 min and steam cleaning drying in a steam bath for 3 min were repeated four times. Except for this, an organic EL device was produced in the same process as in Example 1.

When a voltage of 8 V was applied to the obtained organic EL element, it showed patterned luminescence of 100 cd / m2. Further, when the luminance half-life at the time of constant current driving was measured at an initial luminance of 100 cd / m 2, the luminance half-life was 3000 hr. When the concentration of each solvent in the dried organic functional layer was measured, the concentrations of toluene, diethylbenzene, and tridecafluorohexyl methyl ether were <0.1 ppm (below the detection limit).

(Example 3)
In the drying process, an organic EL element was produced using the apparatus shown in FIG. 5 for drying the organic functional layer. The substrate cooler of this example used a SUS316 box in which cooling water at 20 ° C. was circulated, and the substrate was brought into close contact with a leaf spring. Methyl nonafluorobutyl ether was used as a clean and dry solvent. After drying by exposure to steam for 30 min in a steam bath, the substrate was taken out and heated on a hot plate at 150 ° C. for 30 min in a nitrogen atmosphere.

When a voltage of 8 V was applied to the obtained organic EL element, it showed patterned luminescence of 100 cd / m2. Further, when the luminance half-life at the time of constant current driving was measured at an initial luminance of 100 cd / m 2, the luminance half-life was 6000 hr. Prior to heating in a nitrogen atmosphere, the concentration of each solvent in the dried organic functional layer was 0.1 ppm (below the detection limit) for toluene, diethylbenzene, and methyl nonafluorobutyl ether.

Example 4
Next, an organic EL device was produced in the same process as in Example 3 except that heptafluoropropyl methyl ether was used as a drying solvent in the drying process.

When a voltage of 8 V was applied to the obtained organic EL element, it showed patterned luminescence of 100 cd / m2. Further, when the luminance half-life at the time of constant current driving was measured at an initial luminance of 100 cd / m 2, the luminance half-life was 6000 hr. The concentration of each solvent in the dried organic functional layer was 0.1 ppm (below the detection limit) for toluene, diethylbenzene, and heptafluoropropyl methyl ether.

(Example 5)
In the drying step, an organic EL element was produced using the cleaning / drying apparatus shown in FIG. 7 for drying the organic functional layer. Methyl nonafluorobutyl ether was used as a clean and dry solvent. After drying by spraying a drying solvent for 30 minutes, the substrate was taken out, and the substrate was heated on a hot plate at 150 ° C. for 30 minutes in a nitrogen atmosphere.

When a voltage of 8 V was applied to the obtained organic EL element, it showed patterned luminescence of 100 cd / m2. Further, when the luminance half-life at the time of constant current driving was measured at an initial luminance of 100 cd / m 2, the luminance half-life was 7000 hr. The concentration of each solvent in the dried organic functional layer before heating in a nitrogen atmosphere was 0.1 ppm (below the detection limit) for toluene, diethylbenzene, and methyl nonafluorobutyl ether.

(Example 6)
Next, an organic EL element was produced in the same process except that heptafluoropropyl methyl ether was used as a dry solvent and an apparatus having a configuration as shown in FIG. 9 was used in the drying process. In the drying step, the inside of the apparatus was placed in a nitrogen atmosphere, the pressure of the spray used was 0.1 MPa, and the drying solvent was sprayed for 15 minutes. Next, the substrate was heated to 180 ° C. by an infrared heater provided in the apparatus, and maintained in that state for 1 hr.

When a voltage of 8 V was applied to the obtained organic EL element, it showed patterned luminescence of 100 cd / m2. Further, when the luminance half-life at the time of constant current driving was measured at an initial luminance of 100 cd / m 2, the luminance half-life was 6000 hr. The concentration of each solvent in the dried organic functional layer was 0.1 ppm (below the detection limit) for toluene, diethylbenzene, and heptafluoropropyl methyl ether.

(Example 7)
After forming and drying an organic functional layer made of a mixture of poly (3,4-ethylenedioxythiophene), which is an electron transport layer, and polystyrenesulfonic acid on a transparent conductive film, TFB, which is an interlayer, is made up of 50% toluene. Ink dissolved in a mixed solvent of 50% diethylbenzene was applied in a pattern on the substrate by letterpress printing. The substrate was washed and dried and heat-treated using an apparatus having a configuration as shown in FIG. Ethyl nonafluorobutyl ether was used as a dry solvent. The substrate surface temperature in the heat treatment step was 180 ° C., and the substrate was heated for 1 hour in that state. Thereafter, ethyl nonafluorobutyl ether was again poured over the heated substrate, and the substrate was cooled to room temperature.

After the substrate was taken out of the apparatus and excess TFB was washed away with xylene, poly (2- (2-ethylhexyloxymethoxy) -5-methoxy-1,4-, which is a light-emitting layer, was obtained in the same process as in Example 5. A film of phenylene vinylene) was formed and dried, and a cathode was deposited to produce a device.

When a voltage of 9 V was applied to the obtained organic EL element, it showed patterned luminescence of 100 cd / m2. Further, when the luminance half-life at the time of constant current driving was measured at an initial luminance of 100 cd / m 2, the luminance half-life was 15000 hr. The concentration of each solvent in the dried organic functional layer was 0.1 ppm (below the detection limit) for toluene, diethylbenzene, and heptafluoropropyl methyl ether.

(Comparative Example 1)
The substrate after coating with poly (2- (2-ethylhexyloxymethoxy) -5-methoxy-1,4-phenylenevinylene) was dried by placing it in a vacuum oven at 130 ° C. and 30 Pa for 3 hours, as shown in FIG. An organic EL element was produced in the same manner as in Example 1 except that the apparatus used was not used.

When a voltage of 10 V was applied to the obtained organic EL element, it showed patterned luminescence of 100 cd / m2. Further, when the luminance half-life at the time of constant current driving was measured at an initial luminance of 100 cd / m 2, the luminance half-life was 1500 hr. The concentration of toluene in the dried organic functional layer was 0.1 ppm (below the detection limit), but the concentration of diethylbenzene was 20 ppm.

<Examples of organic solar cells>
(Example 8)
As an organic functional material ink, instead of a mixed solvent of 50% poly (2- (2-ethylhexyloxymethoxy) -5-methoxy-1,4-phenylene vinylene) toluene and 50% diethylbenzene, poly (2- A mixture of methoxy-5- (3,7-dimethyloctyloxy) -1,4-phenylenevinylene) (MDMO-PPV) and [6,6] -phenyl C61-butyric acid methyl ester (PCBM) 1: 4 Is dissolved in paradichlorobenzene (boiling point 180-183 ° C.), the dry solvent is changed to 1,1,2,2,3,3,4-heptafluorocyclopentane, An organic solar cell was produced using the same process as in Example 1 except that the temperature of the rinsing tank was 30 ° C. and 25 ° C., respectively.

The obtained organic solar cell obtained an efficiency of 2.0% at AM1.5. The concentration of each solvent in the dried organic functional layer was 0.1 ppm (below the detection limit) for both paradichlorobenzene and 1,1,2,2,3,3,4-heptafluorocyclopentane.

(Comparative Example 2)
The substrate after application of the MDMO-PPV and PCBM mixed ink was dried by placing it in a vacuum oven at 130 ° C. and 30 Pa for 3 hours, except that the washing and drying apparatus shown in FIG. 4 was not used. An organic solar cell was produced by the same method.

The obtained device obtained an efficiency of 1.5% at AM 1.5. The concentration of paradichlorobenzene in the dried organic functional layer was 50 ppm.

<Examples of organic thin-film transistors>
Example 9
A polyethylene naphthalate (PEN) film was used as a substrate, and a SiO 2 film having a thickness of 30 nm was formed as an inorganic insulating layer. And the ink of Ag nano ink was apply | coated on the board | substrate by letterpress printing, the source electrode and the drain electrode were formed, and it dried at 180 degreeC for 1 minute after formation. Further, a diethylthiophene solution of polythiophene was applied as an organic semiconductor layer between the source electrode and the drain electrode by letterpress printing.

This substrate was placed on a substrate holder and dried by a cleaning / drying apparatus shown in FIG. 1,1,1,3,3-pentafluorobutane was used as a dry solvent. The ultrasonic cleaning was performed for 5 min at 3 frequencies of 26 kHz, 45 kHz, and 100 kHz in a 25 ° C. dry solvent, immersed in a dry solvent at 15 ° C. for 10 min in a rinse bath, and exposed to steam for 3 min in a steam bath. Furthermore, the process of the rinse tank and the steam tank was repeated 3 times.

The substrate after drying was spin coated with an isopropyl alcohol solution of polyvinylphenol as a gate insulating layer and dried at 100 ° C. for 30 minutes. Finally, 30 nm of Al was deposited by mask deposition to obtain a top gate type thin film transistor.

The produced organic thin film transistor showed good Vd-Id characteristics and Vg-Id characteristics. The mobility was about 5 × 10 −4 cm 2 / Vs. The concentrations of diethylbenzene and 1,1,1,3,3-pentafluorobutane in the organic functional layer were <0.1 ppm (below the detection limit).

(Comparative Example 3)
A thin film transistor was manufactured in the same process as in Example 7, except that the drying process after applying the polythiophene diethylbenzene solution was performed using a heat drying method in which the drying process was performed in a 100 ° C. oven for 30 min.

The mobility of the obtained organic thin film transistor was about 3 × 10 −4 cm 2 / Vs. The concentration of diethylbenzene in the organic functional layer was 50 ppm.

The physical properties of the dry solvent used in the above examples and other dry solvents that can be used are shown in Table 1 below. The conditions are an atmospheric pressure of 1 atm and a temperature of 20 degrees. As shown in Table 1, the dry solvents of the examples satisfy the dry solvent conditions described in claim 1 of the claims.

According to the present invention, even when the organic functional layer is produced by the printing method, the characteristics of the organic functional element do not deteriorate due to the removal of the solvent, and the production method that makes it possible to produce a high-performance organic functional element And a manufacturing apparatus is provided. Moreover, according to this invention, the organic functional element manufactured by this manufacturing method, the organic EL element using this method, an organic solar cell, and the manufacturing method of an organic thin-film transistor are provided.

It is sectional drawing of an example of the organic EL element or organic solar cell in this invention. It is sectional drawing of an example of the organic thin-film transistor in this invention. It is a schematic diagram of the printing apparatus in this invention. It is a schematic diagram of the drying apparatus in the present invention. It is a schematic diagram of the drying apparatus in the present invention. It is a schematic diagram of the drying apparatus in the present invention. It is a schematic diagram of the drying apparatus in the present invention. It is a schematic diagram of the drying apparatus in the present invention. It is a schematic diagram of the drying apparatus in the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Translucent substrate 102 ... Transparent conductive layer 103 ... Organic functional layer 103a Charge transport layer or charge transfer layer 103b Organic light emitting layer or active layer 104 ... Electrode layer 201 ... Substrate 202... Inorganic insulating layer 203. Source electrode 204. Drain electrode 205. Organic semiconductor layer 206. Gate insulating layer 207 Gate electrode 301 Ink tank 302 Ink chamber , 303 ... Anilox roll, 304 ... Ink layer, 305 ... Plate cylinder, 306 ... Letterpress, 307 ... Print substrate, 308 ... Flat table, 401 ... Substrate holder, 402 ... Ultrasonic tank, 403 ... Ultrasonic oscillator, 404 ... Rinse tank, 405 ... Steam tank, 406 ... Heater, 407 ... Cooler, 408 ... Dry solvent (liquid), 409 ... Dry Solvent (vapor), 501... Substrate coated with organic functional layer, 502 .. substrate cooler, 601... Cleaning device body, 602 .. intake port, 603 .. exhaust port, 604. ... fog generation tank, 606 ... ultrasonic atomizer, 607 ... dry solvent recovery tank, 608 ... recovered dry solvent, 609 ... dry solvent (mist), 701 ... dry solvent spray apparatus, 702 ... Air blower, 703 ... Moving table, 801 ... Chamber, 802 ... Substrate holder, 803 ... Drain outlet, 804 ... Pressure measuring device, 805 ... Check valve, 806 ... Cleaning solvent tank , 901... Substrate transport rail, 902... Pre-treatment substrate box, 903... Infrared heater, 904.

Claims (13)

A coating liquid in which an organic functional material is dissolved or dispersed in a first organic solvent is used as a coating film on a substrate using a printing method, and a method for producing an organic functional layer comprising the coating film,
A step of applying the coating liquid on a substrate by a printing method to form a coating film;
Next, contacting the substrate with a vapor or liquid of a second organic solvent that does not dissolve the coating film ;
Have
The first organic solvent is toluene, xylene, anisole, methylanisole, dimethylanisole, ethyl benzoate, methyl benzoate, mesitylene, tetralin, amylbenzene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone
Or a mixture of these
The method for producing an organic functional layer, wherein the second organic solvent is a compound containing 5 or more fluorine atoms in one molecule . It is a manufacturing method of the organic functional layer according to claim 1 ,
The step of bringing the coating film into contact with the vapor or liquid of the second organic solvent,
Immersing the substrate in a rinse bath filled with the liquid second organic solvent ;
Next, contacting the substrate with vapor of a second organic solvent ;
The manufacturing method of the organic functional layer characterized by having. It is a manufacturing method of the organic functional layer according to claim 1 ,
The step of bringing the coating film into contact with the vapor or liquid of the second organic solvent,
An organic function comprising: cooling the substrate to a temperature of 10 ° C. or more and 25 ° C. or less and bringing the coating film on the substrate into contact with the atmosphere of the heated and gasified second organic solvent. Layer manufacturing method. It is a manufacturing method of the organic functional layer according to claim 1 ,
The step of bringing the coating film into contact with the vapor or liquid of the second organic solvent,
A method for producing an organic functional layer, characterized by spraying the mist-like second organic solvent onto the substrate. It is a manufacturing method of the organic functional layer according to claim 1 ,
The step of bringing the coating film into contact with the vapor or liquid of the second organic solvent,
Contacting the coating film with the second organic solvent ;
Next, heating the substrate;
And the method is performed in the same space filled with an inert gas atmosphere. In the manufacturing process of an organic functional element including an organic functional layer, at least one organic functional layer is used by using the organic functional layer manufacturing method according to any one of claims 1 to 5. Manufacturing method of a conductive element. It is an organic functional element manufacturing apparatus used for manufacture of the organic functional layer according to claim 2,
A substrate holder having means for moving the substrate in the apparatus, and an ultrasonic oscillator,
An ultrasonic bath capable of holding the liquid of the second organic solvent ;
A rinsing tank capable of holding the liquid of the second organic solvent ;
A steam tank provided with means for generating a vapor of the second organic solvent ;
An organic functional element manufacturing apparatus comprising: It is an organic functional element manufacturing apparatus used for manufacture of the organic functional layer according to claim 3,
A steam tank provided with means for generating a vapor of the second organic solvent ;
A substrate installation part installed immediately above the steam tank;
A substrate cooler connected to the substrate installation section;
An organic functional element manufacturing apparatus comprising: It is an organic functional element manufacturing apparatus used for manufacture of the organic functional layer according to claim 4,
A moving table having movable means, and having a substrate installation unit;
Means for spraying the liquid of the second organic solvent in the form of a mist, the spraying position coincides with the moving table;
A gas spraying device whose spraying position coincides with the moving table;
And the spraying means and the gas spraying device are installed in the order of the spray position of the spraying means and the spraying position of the gas spraying device with respect to the moving direction of the moving table. Organic functional device manufacturing equipment. An organic functional element manufacturing apparatus used for manufacturing the organic functional layer according to claim 5, wherein a sealable chamber;
Means for replacing the atmosphere in the chamber with an inert gas;
Means for atomizing and spraying the liquid of the second organic solvent ;
An organic functional element manufacturing apparatus comprising: An organic functional device manufacturing apparatus according to claim 1 0, the organic functional device manufacturing apparatus characterized by comprising means for heating the substrate. An organic functional device manufacturing apparatus according to claim 1 1,
A moving table having movable means, and having a substrate installation unit;
The means for spraying, wherein the spray position coincides with the moving table;
Means for heating the substrate, wherein a heating position coincides with the moving table;
And the spraying means and the heating means are installed in the order of the spray position of the spraying means and the heating position of the heating means with respect to the moving direction of the movable table. An organic functional element manufacturing apparatus characterized by comprising: Means for heating the substrate, an organic functional device manufacturing apparatus according to claim 1 1 or 1 2, characterized in that a heating by an infrared heater.