WO2023144869A1 - Procédé de récupération de matériau organique - Google Patents

Procédé de récupération de matériau organique Download PDF

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Publication number
WO2023144869A1
WO2023144869A1 PCT/JP2022/002592 JP2022002592W WO2023144869A1 WO 2023144869 A1 WO2023144869 A1 WO 2023144869A1 JP 2022002592 W JP2022002592 W JP 2022002592W WO 2023144869 A1 WO2023144869 A1 WO 2023144869A1
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vapor deposition
organic material
powder
water
aqueous solution
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PCT/JP2022/002592
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English (en)
Japanese (ja)
Inventor
学 二星
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シャープディスプレイテクノロジー株式会社
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Priority to PCT/JP2022/002592 priority Critical patent/WO2023144869A1/fr
Publication of WO2023144869A1 publication Critical patent/WO2023144869A1/fr

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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B33/00—Electroluminescent light sources
    • H05B33/10—Apparatus or processes specially adapted to the manufacture of electroluminescent light sources

Definitions

  • the present invention relates to a method for recovering organic materials.
  • a vacuum vapor deposition method using a vapor deposition mask has been widely used in the manufacture of organic light-emitting devices using low-molecular-weight materials.
  • a vapor deposition apparatus when a glass substrate to be manufactured is coated with a vapor deposition material, the vapor deposition material also adheres to internal jigs in the apparatus such as an anti-adhesion plate and a shutter.
  • the vapor deposition material attached to the internal jig can be reused by collecting it.
  • Patent Document 1 describes the use of water-soluble powder (sodium bicarbonate: NaHCO 3 ) instead of the abrasive in the so-called blast cleaning process, in which the internal jig of the vapor deposition apparatus is cleaned by injecting the abrasive. discloses a method of removing organic materials and separating and recovering the removed organic materials from an aqueous solution of sodium bicarbonate by filtration.
  • water-soluble powder sodium bicarbonate: NaHCO 3
  • the organic material to be recovered is contained in an aqueous solution of sodium bicarbonate (alkaline aqueous solution). A problem arises that the characteristics are degraded.
  • An object of one aspect of the present invention is to realize a recovery method capable of recovering an organic material whose semiconductor characteristics are degraded due to reduction of the electron supply structure without degrading the semiconductor characteristics.
  • an organic material recovery method provides an organic material recovery method for recovering an organic material adhering to an internal jig of a vapor deposition apparatus used in a vapor deposition process of an organic light emitting diode. a removing step of removing the organic material by spraying baking soda powder and water-soluble acidic powder onto the organic material attached to the internal jig; and a recovering step of recovering the organic material from an aqueous solution obtained by dissolving the powder of and the water-soluble acidic powder in water.
  • FIG. 1 is a cross-sectional view showing an element structure of an organic light-emitting diode according to Embodiment 1 of the present invention
  • FIG. FIG. 2 is a schematic diagram of a vapor deposition apparatus used when manufacturing the organic light-emitting diode shown in FIG. 1
  • 4 is a flow chart showing the flow of recovery processing of vapor deposition materials (organic materials).
  • FIG. 4 is a schematic diagram showing an example of a specific method of a step of removing attached substances in the recovery treatment step shown in FIG. 3 ; 4 is a graph showing the relationship between drive time and relative luminance in an implementation device and a comparison device. It is a figure which shows the mode of the carrier balance of a light emitting layer.
  • FIG. 4 is a diagram for explaining the electron transport mechanism in bathophenanthroline, which is a material of the electron transport layer. It is a schematic diagram of electron transport in an electron transport layer.
  • the organic material whose semiconductor characteristics are reduced due to the reduction of the electron supply structure is used to improve the semiconductor characteristics. It is an invention of a method for recovering an organic material without degrading it. In the following embodiments, the organic material recovery method of the present invention will be described in detail.
  • FIG. 1 is a cross-sectional view showing the device structure of an organic light-emitting diode 101 according to this embodiment.
  • FIG. 2 is a schematic diagram of a vapor deposition apparatus 201 used when manufacturing the organic light emitting diode shown in FIG.
  • the organic light-emitting diode 101 includes an Ag electrode (+) layer 12, a hole-injection layer 13, a hole-transport layer 14, a light-emitting layer 15, an electron-transport layer 16, an electron-injection layer, and an electron-injection layer. It has a structure in which a layer 17 and an Ag electrode (-) layer 18 are laminated in order.
  • the Ag electrode (+) layer 12 and the Ag electrode (-) layer 18 are formed by sputtering, and the remaining functional layers (hole injection layer 13, hole transport layer 14, light emitting layer 15, electron The transport layer 16 and the electron injection layer 17) are formed by vapor deposition. That is, on a glass substrate 11, an Ag electrode (+) layer 12 is formed by sputtering, and a hole injection layer 13, a hole transport layer 14, a light emitting layer 15, an electron transport layer 16, and an electron injection layer 17 are formed thereon. are sequentially formed by vacuum deposition using respective organic materials (vapor deposition materials).
  • an Ag electrode ( ⁇ ) layer 18 is formed on the electron injection layer 17 by sputtering to obtain the organic light emitting diode 101 .
  • Vacuum deposition is performed by a deposition device 201 shown in FIG. An outline of the vapor deposition apparatus 201 will be described below.
  • the vapor deposition apparatus 201 includes a vacuum chamber 21, and within the vacuum chamber 21, a vapor deposition source (crucible) 22 for storing vapor deposition materials, and a shutter 23. As shown in FIG. In the vacuum chamber 21, the vapor deposition source 22, the shutter 23, and the glass substrate 11, which is the substrate to be film-formed, are arranged facing each other in this order with a certain gap therebetween.
  • the vapor deposition source 22 heats the vapor deposition material to evaporate (when the vapor deposition material is a liquid material) or sublimate (when the vapor deposition material is a solid material) to generate gaseous vapor deposition particles 24 .
  • the vapor deposition source 22 injects vapor deposition particles 24 gasified in this manner toward the glass substrate 11 .
  • the shutter 23 arranged between the vapor deposition source 22 and the glass substrate 11 , the vapor deposition particles 24 in gaseous form are ejected onto the glass substrate 11 .
  • the shutter 23 is closed.
  • the Ag electrode (+) layer 12 is formed in advance by sputtering on the surface of the glass substrate 11 facing the vapor deposition source 22 .
  • Each functional layer (hole injection layer 13, hole transport layer 14, light emitting layer 15, electron transport layer 16, electron injection layer 17) shown in FIG. 1 is sequentially formed on the Ag electrode (+) layer 12. .
  • the vapor deposition material in the vapor deposition source 22 is changed according to each functional layer, and the shutter 23 is also changed according to each functional layer.
  • the vapor deposition particles 24 adhere to internal jigs such as the shutter 23 in addition to the glass substrate 11, which is the film-forming substrate.
  • the deposited vapor deposition particles 24 can be reused by being collected. Collection of vapor deposition particles 24 will be described below.
  • FIG. 3 is a flow chart showing the flow of collection processing of vapor deposition particles 24 .
  • FIG. 4 is a schematic diagram showing an example of a method of removing the adhering deposition particles 24 by baking soda blasting.
  • the vapor-deposited particles 24 to be removed are bathophenanthroline (Bphen), which is the material of the electron transport layer 16 .
  • step S11 shown in FIG. 3 deposits (evaporation particles 24) are removed (removal step). Specifically, vapor deposition particles 24 adhering to shutter 23 are removed.
  • the deposited particles 24 are removed from the shutter 23 by a sodium bicarbonate blast method.
  • media 31 made by adding citric acid powder (acidic powder) to baking soda (sodium bicarbonate) powder is sprayed from a nozzle 32 onto vapor deposition particles 24 to be collected adhering to shutter 23 . remove by
  • Media 31 is made by adding 5% by weight of citric acid powder to baking soda powder.
  • the amount of citric acid powder to be added may be an amount that neutralizes at least part of the aqueous solution obtained in the recovery step (step S12) described later.
  • the amount of citric acid powder to be added is for pH adjustment, and the amount is such that the hydrogen ion exponent pH of the aqueous solution obtained in the recovery step (step S12) described later is 6.0 or more and 8.0 or less.
  • the amount of the citric acid powder to be added may be an amount that makes the hydrogen ion concentration and the hydroxide ion concentration in the aqueous solution obtained in the recovery step (step S12) described later equal.
  • step S12 shown in FIG. 3 the removed material is collected (collecting step). Specifically, the deposits removed in step S11 are collected.
  • the collected adhering matter (hereinafter referred to as “collected matter”) contains the vapor deposition particles 24 as well as sodium bicarbonate powder and citric acid powder.
  • step S13 shown in FIG. 3 the recovered material is solubilized.
  • the sodium bicarbonate and citric acid contained in the recovered material are water-soluble, and the deposited particles 24 are not water-soluble, the properties of the aqueous solution obtained by solubilizing the recovered material are determined by the amounts of sodium bicarbonate and citric acid.
  • the medium 31 used for removing the deposited particles 24 is made by adding 5% by weight of citric acid powder to the sodium bicarbonate powder. Gender is almost neutral.
  • step S14 shown in FIG. 3 the vapor deposition material (material of the vapor deposition particles 24) is filtered and separated. Specifically, after heating the aqueous solution of the recovered material solubilized in step S13 to about 70° C., it is filtered to separate the vapor deposition material. After separation of the vapor deposition material, the vapor deposition material is dried, purified by sublimation to improve purity, and reused for vapor deposition.
  • the organic material especially the vapor deposition particles 24 which are the vapor deposition material of the electron transport layer 16
  • the organic material whose semiconductor characteristics are deteriorated due to the reduction of the electron supply structure is recovered without degrading the semiconductor characteristics.
  • step S11 the degree of deterioration during continuous energization of the organic light-emitting diode 101 (implementation device) produced using the vapor deposition material recovered by the recovery method described above will be described below.
  • deposits are removed by a baking soda blast method using only baking soda without adding citric acid.
  • the degree of deterioration of organic light-emitting diodes (comparative element) manufactured by reusing the vapor deposition particles 24 obtained from the removed deposits during continuous energization is compared.
  • FIG. 5 is a graph showing the relationship between the drive time and the relative luminance in the experimental device and the comparative device.
  • a current value was set to give an initial luminance of 5000 cd/m 2 for each element by DC continuous energization, and the relative luminance decreased with the passage of time after lighting was measured.
  • FIG. 6 is a diagram showing the state of carrier balance in the light-emitting layer 15.
  • Reference numeral 1061 indicates a state in which the carriers are balanced, and reference numeral 1062 indicates a state in which the carrier is not balanced, particularly when the electron carrier concentration is lowered. showing.
  • Carriers flow into the light-emitting layer 15 from the adjacent hole-transporting layer 14 and electron-transporting layer 16, respectively.
  • the efficiency of light emission is improved.
  • the inflow of carriers from the electron transport layer 16 decreases, that is, when the transportability (electron carrier concentration) of electron transport decreases, the carriers in the light emitting layer 15 are out of balance, resulting in light emission. The efficiency of light emission of layer 15 is reduced.
  • the decrease in the luminescence efficiency of the light-emitting layer 15 due to the decrease in the transportability of electrons becomes noticeable at the initial stage of energization (portion surrounded by a dashed line in FIG. 5). Therefore, in the stage after the initial stage of energization, even if the deterioration of the element is gradual, as shown in the graph of FIG. In the case of the embodiment element in which deterioration of the element is gradual, the time required to decrease to the same relative luminance is longer.
  • FIG. 7 is a diagram for explaining the mechanism of electron transport in bathophenanthroline, which is the material of the electron transport layer 16.
  • FIG. 8 is a schematic diagram of electron transport in the electron transport layer 16 .
  • bathophenanthroline reacts with the electron-emitting portion of the electron-transporting material (the nitrogen (N)-substituted portion of the benzene ring) in an alkaline atmosphere to reduce the electron-donating structure. and the electron transport property is lowered. That is, in step S11 shown in FIG. 3, when only baking soda powder is used as the media 31 when removing the deposition particles 24 adhering to the shutter 23, the liquidity of the aqueous solution of the recovered material becomes alkaline.
  • OH ⁇ hydrogen ion
  • the nitrogen-substituted site of the benzene ring of bathophenanthroline which is the material of vapor deposition particles 24
  • electron transfer is inhibited.
  • OH— inhibits the electrons emitted from the nitrogen-substituted site of the benzene ring of bathophenanthroline from moving to the nitrogen-substituted site of the benzene ring of another bathophenanthroline. do.
  • the inhibition of electron emission from the benzene ring of bathophenanthroline is due to OH- , and this OH- is due to the alkaline solution.
  • the media 31 containing only sodium bicarbonate is used to collect the vapor deposition particles 24
  • the liquidity of the aqueous solution of the collected material becomes alkaline, which hinders the movement of electrons. Therefore, as shown in step S11 in FIG. 3, if the media 31 in which citric acid powder is mixed with baking soda powder is used to recover the deposited particles 24, the liquidity of the aqueous solution of the recovered material is neutral or medium. get closer to sex. This makes it difficult for OH- to inhibit electron emission from the benzene ring of bathophenanthroline.
  • the electron-supplying structure in bathophenanthroline is not reduced, and a decrease in the electron-transporting property in the electron-transporting layer 16 can be avoided.
  • the organic material especially bathophenanthroline, which is the vapor deposition particles 24 of the electron transport layer 16
  • the organic material whose semiconductor characteristics are deteriorated due to the reduction of the electron supply structure can be replaced with semiconductor characteristics. It turns out that it can be recovered without lowering.
  • the media 31 is made by adding 5% by weight (molar ratio: 2.3%) of citric acid powder to sodium bicarbonate powder in order to collect the deposited particles 24 adhering to the shutter 23. was using
  • 5% by weight molar ratio: 2.3%
  • the amount of citric acid powder added to the sodium bicarbonate powder is increased to increase the acid concentration will be described.
  • the deposited particles 24 adhering to the shutter 23 are collected using a medium in which 35% by weight (16% by mole) of citric acid powder is added to baking soda powder.
  • citric acid can reduce the influence of OH-, so that the same effect as in Embodiment 1, that is, the effect that OH- does not easily inhibit the release of electrons from the benzene ring of bathophenanthroline occurs.
  • the liquidity of the aqueous solution of the collected material should be neutral or acidic.
  • the concentration of citric acid added to the sodium bicarbonate powder is increased, and the liquidity of the aqueous solution of the recovered material changes from neutral to acidic, there is no effect on the electron transport layer 16, but there is no effect on the hole transport layer 14. receive.
  • the aqueous solution of the collected material becomes acidic, the material of the hole transport layer 14 is damaged, and the hole transport property of the hole transport layer 14 is lowered.
  • damage to the material of the hole transport layer 14 has a greater impact on shortening the lifetime of the device than damage to the material of the electron transport layer 16.
  • the media 31 for recovering the vapor deposition material has the amount of citric acid to be added to the sodium bicarbonate powder so that the aqueous solution of the recovered material becomes weakly alkaline from a neutral range that does not enter the acidic range. Adjusting is preferred. Taking these things into account, the amount of citric acid powder added to the baking soda powder is preferably 35% by weight (16% molar ratio). 14 materials can be damaged.
  • any water-soluble acidic powder can be used as a neutralizing agent for sodium bicarbonate powder.
  • succinic acid calcium malate, fumaric acid, tartaric acid, powders of carboxylic acid-based crystal materials used as food additives, etc. There may be.
  • a method for recovering an organic material according to aspect 1 of the present invention is to recover an organic material (evaporation particles 24) adhering to an internal jig (shutter 23) of a vapor deposition apparatus (201) used in a vapor deposition process of an organic light emitting diode (101).
  • a method for recovering an organic material to be recovered wherein the organic material is removed by injecting sodium bicarbonate powder and water-soluble acidic powder onto the organic material (evaporation particles 24) adhering to the internal jig (shutter 23).
  • a removing step (step S11), and the organic material (vapor deposition particles 24 ) are collected (steps S12 to S14).
  • the organic material is an electron-transporting material
  • the aqueous solution containing the recovered organic material is alkaline
  • the acidic powder is dissolved in addition to baking soda. is closer to neutral than if Therefore, when the organic material to be recovered from the aqueous solution is an electron-transporting material, the electron-supplying structure is not reduced by alkalinity, the effect on electron transport is reduced, and deterioration in semiconductor characteristics can be reduced. . As a result, the organic material whose semiconductor characteristics are degraded due to reduction of the electron supply structure can be recovered without degrading the semiconductor characteristics.
  • the amount of the water-soluble acidic powder injected in the removal step (step S11) is the aqueous solution obtained in the recovery step (step S13). may be an amount that neutralizes at least a portion of.
  • the organic material can be recovered while reducing the alkaline influence of sodium bicarbonate.
  • the amount of water-soluble acidic powder may be increased to shift the aqueous solution from alkaline to neutral and from neutral to acidic.
  • the hole transport property of the hole transport layer is deteriorated.
  • a decrease in hole transportability in the hole transport layer has a greater influence on the organic light-emitting diode (device life) than a decrease in electron transportability. Therefore, it is preferable that the aqueous solution of the collected material is weakly alkaline to neutral.
  • a method for recovering an organic material according to aspect 3 of the present invention is the method according to aspect 1, wherein the amount of the water-soluble acidic powder injected in the removal step (step S11) is the aqueous solution obtained in the recovery step (step S13).
  • the amount may be such that the hydrogen ion exponent pH of is 6.0 or more and 8.0 or less.
  • the amount of the aqueous solution obtained in the recovery step is such that the hydrogen ion exponent pH of the aqueous solution is 6.0 or more and 8.0 or less, the aqueous solution is neutral. Organic material can be recovered with reduced impact.
  • a method for recovering an organic material according to aspect 4 of the present invention is the method according to aspect 1, wherein the amount of the water-soluble acidic powder injected in the removal step (step S11) is the aqueous solution obtained in the recovery step (step S13).
  • the hydrogen ion concentration and the hydroxide ion concentration contained in may be equal.
  • the aqueous solution obtained in the recovery step if the hydrogen ion concentration and the hydroxide ion concentration contained in the aqueous solution obtained in the recovery step are equal, the aqueous solution is neutral, so the alkalinity effect of sodium bicarbonate. can be reduced to recover the organic material.
  • a method for recovering an organic material according to aspect 5 of the present invention is the method according to any one of aspects 1 to 4, wherein the organic material to be recovered (deposited particles 24) is an electron transport layer of the organic light emitting diode (101).
  • the material of (16) may also be used.
  • the present invention is not limited to the above-described embodiments, but can be modified in various ways within the scope of the claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. is also included in the technical scope of the present invention. Furthermore, new technical features can be formed by combining the technical means disclosed in each embodiment.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Electroluminescent Light Sources (AREA)

Abstract

Un procédé de récupération d'un matériau organique selon la présente invention comprend : une étape d'élimination pour éliminer des particules de dépôt en phase vapeur (24) adhérant à un obturateur (23) par production d'un jet d'une poudre de bicarbonate de sodium et d'un jet d'une poudre acide soluble dans l'eau (étape S11) ; et une étape de récupération pour récupérer les particules de dépôt en phase vapeur (24) à partir d'une solution aqueuse dans laquelle les particules de dépôt en phase vapeur éliminées (24), la poudre de bicarbonate de sodium et la poudre acide soluble dans l'eau sont dissoutes dans l'eau (étapes S12 à S14). Par conséquent, les particules de dépôt en phase vapeur 24 peuvent être récupérées sans diminuer les caractéristiques de semi-conducteur.
PCT/JP2022/002592 2022-01-25 2022-01-25 Procédé de récupération de matériau organique WO2023144869A1 (fr)

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PCT/JP2022/002592 WO2023144869A1 (fr) 2022-01-25 2022-01-25 Procédé de récupération de matériau organique

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PCT/JP2022/002592 WO2023144869A1 (fr) 2022-01-25 2022-01-25 Procédé de récupération de matériau organique

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3103377U (ja) * 2004-01-02 2004-08-12 有限会社千代田メンテナンス スプレー方式の洗浄装置
KR20090122035A (ko) * 2008-05-23 2009-11-26 풍원화학(주) 유기전계발광표시장치 제조공정에서 사용되는 도전부재를세정하기 위한 세정장치, 세정방법 및 전해세정약품
JP2014042859A (ja) * 2012-08-24 2014-03-13 Micron Metal Co Ltd 有機材料の除去方法
WO2019053559A1 (fr) * 2017-09-12 2019-03-21 株式会社半導体エネルギー研究所 Élément électroluminescent, dispositif électroluminescent, dispositif électronique et dispositif d'éclairage

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3103377U (ja) * 2004-01-02 2004-08-12 有限会社千代田メンテナンス スプレー方式の洗浄装置
KR20090122035A (ko) * 2008-05-23 2009-11-26 풍원화학(주) 유기전계발광표시장치 제조공정에서 사용되는 도전부재를세정하기 위한 세정장치, 세정방법 및 전해세정약품
JP2014042859A (ja) * 2012-08-24 2014-03-13 Micron Metal Co Ltd 有機材料の除去方法
WO2019053559A1 (fr) * 2017-09-12 2019-03-21 株式会社半導体エネルギー研究所 Élément électroluminescent, dispositif électroluminescent, dispositif électronique et dispositif d'éclairage

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