WO2019022120A1 - Matériau à fission de singulet, sensibilisateur de triplet, composé et film mince - Google Patents

Matériau à fission de singulet, sensibilisateur de triplet, composé et film mince Download PDF

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WO2019022120A1
WO2019022120A1 PCT/JP2018/027847 JP2018027847W WO2019022120A1 WO 2019022120 A1 WO2019022120 A1 WO 2019022120A1 JP 2018027847 W JP2018027847 W JP 2018027847W WO 2019022120 A1 WO2019022120 A1 WO 2019022120A1
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light emitting
compound
triplet
layer
general formula
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PCT/JP2018/027847
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Japanese (ja)
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弘典 梶
功將 志津
壮太郎 檜垣
安達　千波矢
憲一 合志
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国立大学法人九州大学
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Priority to JP2019532824A priority Critical patent/JP7214142B2/ja
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C15/00—Cyclic hydrocarbons containing only six-membered aromatic rings as cyclic parts
    • C07C15/20—Polycyclic condensed hydrocarbons
    • C07C15/38—Polycyclic condensed hydrocarbons containing four rings
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/06—Luminescent, e.g. electroluminescent, chemiluminescent materials containing organic luminescent materials
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
    • H10K50/11—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers
    • H10K50/12—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers comprising dopants

Definitions

  • the present invention relates to compounds useful as singlet fission materials and triplet sensitizers.
  • acenes having a structure in which a plurality of benzene rings are linearly condensed have a wide ⁇ conjugated system
  • applications as functional materials of organic devices such as organic semiconductor materials and light emitting materials are expected, and useful applications are Research is in progress to find out.
  • a compound having a tetracene skeleton is used as a material of an organic light emitting device.
  • Patent Document 1 describes an example in which this compound is used as a dopant of a light emitting layer
  • Patent Document 2 describes an example in which this compound is used in a hole transport layer ing.
  • the compound having a tetracene skeleton is known to be used as a dopant of a light emitting layer of an organic light emitting device or a hole transporting material.
  • the properties of the compound having a tetracene skeleton have not been sufficiently studied, and it is considered that many untouched areas remain for its usefulness. Therefore, in order to develop new materials having higher utility, it is required to conduct further research on compounds having a tetracene skeleton. Under these circumstances, we investigated the characteristics and usefulness of the compound having a tetracene skeleton, and conducted intensive studies for the purpose of finding out new applications.
  • tetracene compounds having a specific structure have useful properties of causing singlet splitting and increasing the number of triplet excitons. And it came to the thought that the organic device with high efficiency will be realized by utilizing the characteristic of the tetracene compound.
  • the present invention has been proposed based on these findings, and specifically has the following configuration.
  • a singlet fission material comprising a compound represented by the following general formula (1).
  • R 1 represents a substituted or unsubstituted aryl group.
  • One of R 2 and R 3 is a hydrogen atom, and the other is a substituted or unsubstituted aryl group.
  • R 1 and R 2 are each independently an unsubstituted aryl group.
  • R 3 The singlet fission material according to [1] or [2], wherein R 1 and R 2 are the same.
  • a triplet sensitizer comprising the compound represented by the following general formula (1).
  • R 1 represents a substituted or unsubstituted aryl group.
  • One of R 2 and R 3 is a hydrogen atom, and the other is a substituted or unsubstituted aryl group.
  • [5] The triplet sensitizer described in [4], wherein R 1 and R 2 are each independently an unsubstituted aryl group.
  • [6] The triplet sensitizer according to [4] or [5], wherein R 1 and R 2 are the same.
  • one of R 4 and R 5 is a hydrogen atom, and the other is a substituted or unsubstituted aryl group.
  • R 6 and R 7 is a hydrogen atom, and the other is a substituted or unsubstituted aryl group. n is 0 or 1.
  • R 4 and R 6 are each independently an unsubstituted aryl group.
  • R 4 and R 6 are the same.
  • the compounds in the present invention are useful as singlet fission materials and triplet sensitizers. High efficiency can be realized by using the singlet fission material or the triplet sensitizer of the present invention as the functional material of the organic device.
  • FIG. 10 shows the emission spectra of respective toluene solutions containing Compound 1, Compound 3 or Compound 4.
  • FIG. It is an emission spectrum of each thin film in which the concentration of compound 1 is 0% by weight, 6% by weight, 30% by weight or 100% by weight. It is a transient absorption decay curve at 530 nm of a chloroform solution in which the concentration of Compound 1 is 5 ⁇ 10 ⁇ 2 mol / L.
  • the concentration of the compound 1 is 1 ⁇ 10 ⁇ 3 mol / L, 1 ⁇ 10 ⁇ 2 mol / L, 2.5 ⁇ 10 ⁇ 2 mol / L, 5 ⁇ 10 ⁇ 2 mol / L, or 1 ⁇ 10 ⁇ 1 mol
  • FIG. 6 is a correlation diagram in which the amount of change in absorbance ⁇ ABS at 530 nm is plotted on the vertical axis and the intensity of excitation light on the horizontal axis for certain chloroform solutions.
  • 5 is a graph showing the concentration dependency of the triplet exciton generation efficiency IS ISC of Compound 1.
  • a numerical range represented using “to” means a range including numerical values described before and after “to” as the lower limit value and the upper limit value.
  • the isotope species of the hydrogen atom present in the molecule of the compound used in the present invention is not particularly limited. For example, all hydrogen atoms in the molecule may be 1 H, or some or all of the hydrogen atoms may be 2 H (Deuterium D) may be used.
  • the “fluorescent material” is a light emitting material in which the emission intensity of fluorescence is higher than that of phosphorescence when light emission is observed at 20 ° C.
  • the “phosphorescent material” is When light emission is observed at 20 ° C., it is a light emitting material in which the light emission intensity of phosphorescence is higher than the light emission intensity of fluorescence.
  • the “delayed fluorescent material” is a material in which both fluorescence having a short emission lifetime at 20 ° C. and fluorescence having a long emission lifetime (delayed fluorescence) are observed.
  • a light emitting organic compound other than the organometallic complex is usually a fluorescent material or a delayed fluorescent material.
  • thin film means a film having a thickness of 1000 nm or less, preferably 500 nm or less, and more preferably 100 nm or less.
  • R 1 represents a substituted or unsubstituted aryl group.
  • One of R 2 and R 3 is a hydrogen atom, and the other is a substituted or unsubstituted aryl group.
  • the substituted or unsubstituted aryl group represented by one of R 2 and R 3 and the substituted or unsubstituted aryl group represented by R 1 may be the same as or different from each other, but are preferably the same.
  • the aryl group (a part excluding a substituent in the case of a substituted aryl group) in the "substituted or unsubstituted aryl group" preferably has 6 to 26 ring atoms, more preferably 6 to 22 and more preferably 6 to 18 Is more preferred.
  • Specific examples of the aryl group include phenyl group, 1-naphthalenyl group, 2-naphthalenyl group, 1-anthracenyl group, 2-anthracenyl group, 9-anthracenyl group, 1-tetracenyl group, 2-tetracenyl group, 5-tetracenyl group, 1-pyrenyl group and 2-pyrenyl group can be mentioned.
  • the aryl group that can be taken by R 1 to R 3 may be substituted or unsubstituted with a substituent, but at least one of R 1 to R 3 is preferably an unsubstituted aryl group It is preferable that all of the substituted or unsubstituted aryl groups that R 1 to R 3 can be substituted be unsubstituted aryl groups.
  • the substituent is preferably an alkyl group or an aryl group.
  • the alkyl group may be linear, branched or cyclic.
  • the preferred carbon number is 1 to 20, more preferably 1 to 10, and still more preferably 1 to 6.
  • methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group and the like can be exemplified.
  • the preferable range and specific example of the aryl group the preferable range and specific example of the aryl group in the above-mentioned "substituted or unsubstituted aryl group" can be referred to.
  • the alkyl group and aryl group which are substituents may be further substituted, and an alkyl group and an aryl group can be mentioned preferably as a substituent in that case.
  • the total carbon number of the substituted or unsubstituted aryl group that can be taken by R 1 to R 3 is preferably 6 to 32, more preferably 6 to 28, and still more preferably 6 to 24.
  • substituted aryl groups that R 1 to R 3 may be include alkylphenyl group (tolyl group, tert-butylphenyl group etc.), biphenyl group, alkylbiphenyl group (methylbiphenyl group, tert-butylbiphenyl group etc.), ter Phenyl group, alkyl terphenyl group (methyl terphenyl group, tert-butyl terphenyl group etc.), phenyl naphthyl group, alkyl naphthyl group (methyl naphthyl group, tert-butyl naphthyl group etc.), phenyl anthracenyl group, naphthyl anthracene Cenyl group, alkyl an
  • the compound represented by the following general formula (2) is a novel compound.
  • one of R 4 and R 5 is a hydrogen atom, and the other is a substituted or unsubstituted aryl group.
  • One of R 6 and R 7 is a hydrogen atom, and the other is a substituted or unsubstituted aryl group.
  • n is 0 or 1.
  • the description and the preferred range of the substituted or unsubstituted aryl group in the general formula (2) and the specific examples can be referred to the description of the substituted or unsubstituted aryl group in the general formula (1).
  • the substituted or unsubstituted aryl group represented by one of R 4 and R 5 and the substituted or unsubstituted aryl group represented by one of R 6 and R 7 may be the same or different.
  • Preferred examples of the compound represented by the general formula (2) include compounds wherein R 4 and R 6 are each independently a substituted or unsubstituted aryl group, and R 5 and R 7 are a hydrogen atom. .
  • R in the above reaction formula the description of the substituted or unsubstituted aryl group in the general formula (2) can be referred to.
  • the bitetracenone used here may be either cis or trans, or a mixture of cis and trans.
  • the details of the above reaction can be referred to the synthesis examples described below.
  • the compound represented by General formula (2) can also be synthesize
  • the compounds represented by the general formula (1) are useful as singlet fission materials.
  • “singlet splitting” refers to a phenomenon in which a singlet exciton is split into two triplet excitons
  • “singlet splitting material” in the present invention means an excited singlet state S.
  • the fact that it is a singlet fission material means, for example, that each thin film formed by adding the compound represented by General Formula (1) in different concentrations to the host material was irradiated with excitation light to measure the photoluminescence quantum yield Sometimes, it can be confirmed by the correlation that the photoluminescence quantum yield decreases as the concentration of the compound increases.
  • the compound represented by the general formula (1) which is a singlet fission material
  • the “triplet sensitizer” in the present invention means the material to increase the number of causing the singlet fission triplet excitons when excited to an excited singlet state S 1.
  • the effect of increasing the number of triplet excitons by singlet splitting may be referred to as "triplet exciton sensitization effect”.
  • the fact that it is a triplet sensitizer means that the solution containing the compounds represented by the general formula (1) in different concentrations is irradiated with pump light as excitation light, and immediately thereafter, the change in absorbance to the probe light when measuring the amount .DELTA.ABS, confirmed by from the .DELTA.ABS using the following formula (I) is a triplet exciton generation efficiency [Phi ISC obtained, correlation increases with the concentration of the compound is high is observed can do.
  • ⁇ ABS absorbance change amount
  • IS ISC indicates the triplet exciton generation efficiency
  • I 0 indicates the intensity of pump light (excitation light intensity) irradiated to the solution
  • ⁇ ABS indicates the change in absorbance
  • ⁇ T denotes the molar absorption coefficient of the target compound at the probe light wavelength
  • c denotes the concentration of the target compound in the solution
  • L denotes the measurement
  • the optical path length (1 mm) of the used cell is shown.
  • light of 337 nm in the absorption band of the target compound can be used as pump light, and light of 510-540 nm in the absorption band of the target compound can be used as probe light.
  • a triplet sensitizer composed of the compound represented by the general formula (1) for the material of the organic device the efficiency can be dramatically improved.
  • a triplet sensitizer composed of a compound represented by the general formula (1) as a material of the organic semiconductor layer of the organic solar cell, light irradiated to the organic semiconductor layer in the organic solar cell is
  • the compound represented by the general formula (1) can be absorbed to form a singlet exciton, and a triplet amplification system can be realized in which the singlet exciton is split into two triplet excitons.
  • triplet excitons are efficiently generated by light irradiation, and since the triplet excitons have a long lifetime, triplet excitation is generated at the p / n junction interface of the organic semiconductor layer.
  • the probability of charge arrival and separation of charge is high, and holes and electrons can be efficiently extracted to the electrode. Therefore, compared with the organic solar cell which does not contain a triplet sensitizer, high photoelectric conversion efficiency can be obtained.
  • the organic light emitting device was formed with the host material of an excited singlet state It is possible to realize an excited triplet energy amplification system in which a singlet exciton is split into two triplet excitons and their excited triplet energy is transferred to the light emitting material by the Dexter transfer mechanism.
  • the excitation triplet energy is efficiently generated by the excitation of the host material and supplied to the light emitting material, so that the host material does not have the triplet exciton sensitizing effect. In comparison, high luminous efficiency can be obtained.
  • the light emitting material may be any phosphorescent material that can emit light upon receiving excitation triplet energy from the host material, and may emit light by radiative relaxation from the excitation triplet state, or the excitation triplet state It may be a delayed fluorescent material which emits light by radiative relaxation from the excited singlet state after producing an inverse intersystem crossing from the light emitting element to the excited singlet state.
  • a triplet sensitizer of the present invention as a host material of the light emitting layer, in order to obtain higher luminous efficiency, transfer of excited triplet energy from the host material to the light emitting material is facilitated. It is preferable to confine the excited triplet energy received by the light emitting material in the molecule of the light emitting material.
  • the host material preferably has a lowest excitation triplet energy level higher than the lowest excitation triplet energy level of the light emitting material. Furthermore, in order to confine the excited singlet energy generated in the light emitting material in the molecule of the light emitting material, the host material is required to have its lowest singlet excitation energy level higher than the lowest singlet excitation energy level of the light emitting material preferable.
  • a singlet sensitizing layer containing a singlet sensitizer may be provided next to the light emitting layer in the organic light emitting device using the triplet sensitizer of the present invention as a host material of the light emitting layer, and further An electron and triplet exciton blocking layer may be provided between the light emitting layer and the singlet sensitizing layer.
  • the “singlet sensitizer” refers to a material having a generation probability [S 1 / (S 1 + T 1 )] of the excited singlet state S 1 generated by current excitation larger than 25%, for example A delayed fluorescent material can be used.
  • the singlet sensitizer preferably has a lowest excited singlet energy level higher than the lowest excited singlet energy level of the host material, and the lowest excited singlet energy level and the lowest excited triplet energy level
  • the difference ⁇ E ST is preferably 0.3 eV or less.
  • ACRXTN mentioned later can be mentioned.
  • the “electron and triplet exciton blocking layer” refers to a layer having a function of blocking the transfer of electrons and triplet excitons from the singlet sensitizing layer to the light emitting layer.
  • the triplet sensitizer which consists of a compound represented by General formula (1) can be used also as an assist dopant of the light emitting layer of an organic light emitting element.
  • assist dopant has a function of receiving excited singlet energy from a host material, converting it into excited triplet energy, and transferring the excited triplet energy to a light emitting material.
  • a light emitting material which receives excitation triplet energy from the assist dopant is excited by the energy to emit light.
  • a triplet sensitizer composed of a compound represented by the general formula (1) is used as such an assist dopant, singlet excitons generated when the assist dopant receives excited singlet energy become two triplet excitons.
  • the light emitting material can be more efficiently supplied with excitation triplet energy. Therefore, higher luminous efficiency can be obtained as compared with the case of using an assist dopant having no triplet exciton sensitization effect.
  • a usual host material can be used as a host material, but it is preferable to use a delayed fluorescent material because it can efficiently generate excited singlet energy.
  • the light-emitting material may be any material as long as it can emit light by receiving excitation triplet energy from the assist dopant, and a phosphorescent material or a delayed fluorescent material can be used.
  • the host material in order to obtain higher luminous efficiency, transfer of excited singlet energy from the host material to the assist dopant, transfer from the assist dopant to the light emitting material It is preferable to facilitate the transfer of the excited triplet energy and to confine the excited triplet energy received by the light emitting material in the molecule of the light emitting material. Therefore, the host material preferably has a lowest excited singlet energy level higher than the lowest excited singlet energy level of the assist dopant, and a lowest excited triplet energy level corresponds to the lowest excited triplet energy quasi of the assist dopant. And higher than the lowest excitation triplet energy level of the luminescent material.
  • the assist dopant preferably has a lowest excitation triplet energy level higher than the lowest excitation triplet energy level of the light emitting material. Furthermore, in order to confine the excited singlet energy generated in the light emitting material in the molecule of the light emitting material, the host material and the assist dopant have their lowest singlet excitation energy level higher than the lowest singlet excitation energy level of the light emitting material Higher is more preferred.
  • the compound represented by the general formula (1) causes singlet splitting to increase the number of triplet excitons, an organic device other than the organic solar cell and the organic light emitting element, for example, an organic imaging element Even when used as a material for a vein authentication apparatus, a blood glucose level monitor, etc., it contributes to the improvement of the efficiency, and can be effectively used as a functional material of various organic devices.
  • the compound represented by the general formula (1) is also characterized in that it can be formed as an amorphous solid. Therefore, destruction of the organic film structure due to repeated driving and property deterioration which would be a problem in an organic device using a crystalline singlet fission material can be avoided, and an organic device having high stability can be realized.
  • the layer configuration of the organic light emitting element and the material used for each layer will be described.
  • the triplet sensitizer consisting of the compound represented by the general formula (1) of the present invention can be effectively used as a host material or an assist dopant of the light emitting layer of the organic light emitting device.
  • An excellent organic light emitting device such as an EL device
  • the organic photoluminescent device has a structure in which at least a light emitting layer is formed on a substrate.
  • the organic electroluminescent device has a structure in which an organic layer is formed at least an anode, a cathode, and between the anode and the cathode.
  • the organic layer includes at least a light emitting layer, and may be formed only of the light emitting layer, or may have one or more organic layers in addition to the light emitting layer.
  • a hole transport layer, a hole injection layer, an electron blocking layer, a hole blocking layer, an electron injection layer, an electron transport layer, an exciton blocking layer and the like can be mentioned.
  • the hole transport layer may be a hole injection transport layer having a hole injection function
  • the electron transport layer may be an electron injection transport layer having an electron injection function.
  • FIG. 1 A specific structural example of the organic electroluminescent device is shown in FIG.
  • 1 is a substrate
  • 2 is an anode
  • 3 is a hole injection layer
  • 4 is a hole transport layer
  • 5 is a light emitting layer
  • 6 is an electron transport layer
  • 7 is a cathode.
  • Each member and each layer of an organic electroluminescent element are demonstrated below.
  • the description of the substrate and the light emitting layer also applies to the substrate and the light emitting layer of the organic photoluminescence device.
  • the organic electroluminescent device of the present invention is preferably supported on a substrate.
  • the substrate is not particularly limited as long as it is conventionally used conventionally in organic electroluminescent devices, and for example, those made of glass, transparent plastic, quartz, silicon or the like can be used.
  • anode As an anode in an organic electroluminescent element, what makes an electrode material the large (4 eV or more) metal of a work function, an alloy, an electrically conductive compound, and these mixtures is used preferably.
  • electrode materials include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO 2 , and ZnO.
  • conductive transparent materials such as CuI, indium tin oxide (ITO), SnO 2 , and ZnO.
  • ITO indium tin oxide
  • ZnO ZnO
  • an amorphous material such as IDIXO (In 2 O 3 -ZnO) which can be used to form a transparent conductive film may be used.
  • the anode may form a thin film by depositing or sputtering these electrode materials, and may form a pattern of a desired shape by photolithography, or if it does not require much pattern accuracy (about 100 ⁇ m or more). ), A pattern may be formed through a mask of a desired shape during deposition or sputtering of the electrode material. Or when using the material which can be apply
  • cathode one having a metal having a small work function (4 eV or less) (referred to as electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used.
  • electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al 2 O) 3 ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals etc. may be mentioned.
  • a mixture of an electron-injectable metal and a second metal which is a stable metal having a larger work function value such as a magnesium / silver mixture, Magnesium / aluminium mixtures, magnesium / indium mixtures, aluminum / aluminium oxide (Al 2 O 3 ) mixtures, lithium / aluminium mixtures, aluminum etc. are preferred.
  • the cathode can be produced by forming a thin film of such an electrode material by a method such as vapor deposition or sputtering. Further, the sheet resistance as the cathode is preferably several hundred ohms / square or less, and the film thickness is usually selected in the range of 10 nm to 5 ⁇ m, preferably 50 to 200 nm.
  • the light emitting layer is a layer which emits light after excitons are generated by recombination of holes and electrons injected from each of the anode and the cathode, and contains a host material and a light emitting material, or a host material and an assist material. It contains a dopant and a light emitting material.
  • the light emitting layer contains a host material and a light emitting material
  • the host material one or two or more selected from the compound group represented by General Formula (1), which is a triplet sensitizer of the present invention It can be used.
  • a light-emitting material one which can emit light upon being excited by excited triplet energy transferred from a host material is used.
  • the light emitting layer contains such a host material and a light emitting material
  • excited triplet energy is efficiently generated by the triplet exciton sensitizing effect of the host material and is utilized for light emission of the light emitting material, so that high light emission Efficiency can be obtained.
  • organic light emitting device organic photoluminescent device and electroluminescent device
  • light emission is generated from the light emitting material contained in the light emitting layer.
  • This light emission may be either phosphorescence light emission or delayed fluorescence light emission, may include both light emission, and may include normal fluorescence light emission.
  • part or part of light emission may be emitted from the host material.
  • the amount of the light emitting material contained in the light emitting layer is preferably 0.1% by weight or more, more preferably 1% by weight or more, The content is preferably 50% by weight or less, more preferably 20% by weight or less, and still more preferably 10% by weight or less.
  • the light emitting layer contains a host material, an assist dopant, and a light emitting material
  • the assist dopant one or two selected from the compound group represented by General Formula (1) which is a triplet sensitizer of the present invention More than species can be used.
  • the host material one which can transfer the excited singlet energy generated in the host material to the assist dopant is used, and the light emitting material receives the excited triplet energy transferred from the assist dopant and emits light. Use what you get.
  • the host material and the light emitting material used here and the description of the energy levels of the host material, the assist dopant, and the light emitting material, the corresponding description in the column of [Utility of compound represented by General Formula (1)] Can be referenced.
  • the excited singlet energy generated in the host material is efficiently converted to the excited triplet energy by the triplet exciton sensitizing effect of the assist dopant to emit light. Since it is used for light emission of the material, high light emission efficiency can be obtained.
  • light emission is generated from the light emitting material contained in the light emitting layer.
  • This light emission may be either phosphorescence light emission or delayed fluorescence light emission, may include both light emission, and may include normal fluorescence light emission.
  • part or part of light emission may be emitted from the host material or the assist dopant.
  • the content of the assist dopant is less than the content of the host material and more than the content of the light emitting material, that is, “the content of the light emitting material It is preferable to satisfy the relationship of ⁇ content of assist dopant ⁇ content of host material>.
  • the content of the assist dopant in the light emitting layer is preferably less than 50% by weight.
  • the upper limit value of the content of the assist dopant is preferably less than 40% by weight, and the upper limit value of the content may be, for example, less than 30% by weight, less than 20% by weight, and less than 10% by weight.
  • the lower limit is preferably 0.1% by weight or more, and may be, for example, more than 1% by weight and more than 3% by weight.
  • the injection layer is a layer provided between the electrode and the organic layer to lower the driving voltage and improve the luminance, and includes the hole injection layer and the electron injection layer, and between the anode and the light emitting layer or the hole transport layer, And between the cathode and the light emitting layer or the electron transport layer.
  • An injection layer can be provided as needed.
  • the blocking layer is a layer capable of blocking the diffusion of charges (electrons or holes) present in the light emitting layer and / or excitons out of the light emitting layer.
  • An electron blocking layer can be disposed between the light emitting layer and the hole transport layer to block electrons from passing through the light emitting layer towards the hole transport layer.
  • a hole blocking layer can be disposed between the light emitting layer and the electron transport layer to block holes from passing through the light emitting layer towards the electron transport layer.
  • the blocking layer can also be used to block the diffusion of excitons out of the light emitting layer. That is, each of the electron blocking layer and the hole blocking layer can also have the function as an exciton blocking layer.
  • the electron blocking layer or the exciton blocking layer as used herein is used in a sense including one layer having a function of the electron blocking layer and the exciton blocking layer.
  • the hole blocking layer has a function of an electron transport layer in a broad sense.
  • the hole blocking layer plays the role of transporting electrons and blocking the arrival of holes to the electron transporting layer, which can improve the recombination probability of electrons and holes in the light emitting layer.
  • the material of the hole blocking layer the material of the electron transport layer described later can be used as needed.
  • the electron blocking layer has a function of transporting holes in a broad sense.
  • the electron blocking layer plays the role of transporting holes and blocking the arrival of electrons to the hole transport layer, which can improve the probability of recombination of electrons and holes in the light emitting layer. .
  • the exciton blocking layer is a layer for blocking the diffusion of excitons generated by the recombination of holes and electrons in the light emitting layer into the charge transport layer, and the insertion of this layer results in the formation of excitons.
  • the light can be efficiently confined in the light emitting layer, and the light emission efficiency of the device can be improved.
  • the exciton blocking layer can be inserted on either the anode side or the cathode side adjacent to the light emitting layer, or both of them can be simultaneously inserted.
  • the layer when an exciton blocking layer is provided on the anode side, the layer can be inserted between the hole transport layer and the light emitting layer adjacent to the light emitting layer, and when inserted on the cathode side, the light emitting layer and the cathode And the light emitting layer may be inserted adjacent to the light emitting layer.
  • a hole injection layer or an electron blocking layer can be provided between the anode and the exciton blocking layer adjacent to the anode side of the light emitting layer, and the cathode and the excitation adjacent to the cathode side of the light emitting layer.
  • an electron injecting layer, an electron transporting layer, a hole blocking layer, and the like can be provided.
  • the blocking layer is disposed, at least one of the excitation singlet energy and the excitation triplet energy of the material used as the blocking layer is preferably higher than the excitation singlet energy and the excitation triplet energy of the light emitting material.
  • the hole transport layer is made of a hole transport material having a function of transporting holes, and the hole transport layer can be provided as a single layer or a plurality of layers.
  • the hole transport material is one having either hole injection or transport or electron barrier properties, and may be either organic or inorganic.
  • Examples of known hole transport materials that can be used include triazole derivatives, oxadiazole derivatives, imidazole derivatives, carbazole derivatives, indolocarbazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, Amino substituted chalcone derivatives, oxazole derivatives, styryl anthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers, particularly thiophene oligomers, etc., but porphyrin compounds, aroma Group tertiary amine compounds and styrylamine compounds are preferred, and aromatic tertiary amine compounds are more preferred.
  • the electron transporting layer is made of a material having a function of transporting electrons, and the electron transporting layer can be provided in a single layer or a plurality of layers.
  • the electron transporting material (which may also be a hole blocking material) may have a function of transferring electrons injected from the cathode to the light emitting layer.
  • Examples of the electron transport layer that can be used include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyrandioxide derivatives, carbodiimides, flareylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives and the like.
  • a thiadiazole derivative h wherein the oxygen atom of the oxadiazole ring is substituted by a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an electron transport material. It can. Furthermore, it is also possible to use a polymer material in which these materials are introduced into a polymer chain, or in which these materials are used as a polymer main chain.
  • the triplet sensitizer of the present invention may be used not only in the light emitting layer but also in layers other than the light emitting layer.
  • the triplet sensitizer used in the light emitting layer and the triplet sensitizer used in layers other than the light emitting layer may be the same or different.
  • a triplet sensitizer may be used for the above-mentioned injection layer, blocking layer, hole blocking layer, electron blocking layer, exciton blocking layer, hole transporting layer, electron transporting layer, and the like.
  • the film forming method of these layers is not particularly limited, and may be produced by either a dry process or a wet process.
  • the preferable material which can be used for an organic electroluminescent element is illustrated concretely.
  • the materials that can be used in the present invention are not limitedly interpreted by the following exemplified compounds. Moreover, even if it is the compound illustrated as a material which has a specific function, it is also possible to divert it as a material which has another function.
  • a compound example of the delayed fluorescence material is mentioned.
  • Unexamined-Japanese-Patent 2013-253121, WO2013 / 133359, WO2014 / 034535, WO2014 / 115743, WO2014 / 122895, WO2014 / 126200, WO2014 / 136758, WO2014 / 133121 are included.
  • WO 2014/136860 WO 2014/196585, WO 2014/189122, WO 2014/168101, WO 2015/008580, WO 2014/203840, WO 2015/002213, WO 2015/016200, WO 2015/019725, WO 2015/072470, WO 2015/108049, WO 2015 / 80182, WO2015 / 072537, WO2015 / 080183, JP2015-129240, WO2015 / 129714, WO2015 / 129715, WO2015 / 133501, WO2015 / 136880, WO2015 / No.
  • Ar represents an aryl group.
  • the light emitting layer contains a host material, an assist dopant and a light emitting material, preferable compounds which can be used as the host material are listed.
  • a delayed fluorescence material can be preferably used as the host material in this case.
  • compounds of delayed fluorescence materials that can be used as host materials reference can be made to the examples of compounds of delayed fluorescence materials given as preferable examples of light emitting materials.
  • ACRXTN used in the examples can also be preferably used as a host material.
  • the organic electroluminescent device produced by the above-mentioned method emits light by applying an electric field between the anode and the cathode of the obtained device.
  • light emission by excited singlet energy light of a wavelength corresponding to the energy level is confirmed as fluorescence emission and delayed fluorescence emission.
  • a wavelength corresponding to the energy level is confirmed as phosphorescence. Since the ordinary fluorescence has a shorter fluorescence lifetime than the delayed fluorescence, the emission lifetime can be distinguished by the fluorescence and the delayed fluorescence.
  • the excitation triplet energy in the case of ordinary organic compounds, the excitation triplet energy is unstable and converted to heat, etc., and its lifetime is short and it is immediately inactivated, so it can hardly be observed at room temperature.
  • the excited triplet energy of a normal organic compound it can be measured by observing the light emission under conditions of extremely low temperature.
  • the organic electroluminescent device can be applied to any of a single device, a device having a structure arranged in an array, and a structure in which an anode and a cathode are arranged in an XY matrix.
  • an organic light-emitting device whose emission efficiency is greatly improved by containing a triplet sensitizer comprising the compound represented by the general formula (1) as a host material or assist dopant for the light-emitting layer is provided. can get.
  • the organic light emitting device such as the organic electroluminescent device using the triplet sensitizer of the present invention can be applied to various applications.
  • organic electroluminescent display device it is possible to manufacture an organic electroluminescent display device using this organic electroluminescent device, and for details, see “Organic EL Display” (Ohm Corporation) by Shiho Tokishi, Chika Adachi, Hideyuki Murata You can refer to it. Furthermore, in particular, this organic electroluminescent device can also be applied to organic electroluminescent illumination and back light which are in high demand.
  • source meter made by Keithley: 2400 series
  • semiconductor parameter analyzer manufactured by Agilent Technologies: E5273A
  • optical power meter measuring device manufactured by Newport: 1930C
  • optical spectroscope Ocean Optics, Inc .: USB 2000
  • a spectroradiometer Topcon, SR: 3
  • a streak camera Hamamatsu Photonics Co., Ltd., C4334 type
  • the measurement of absorbance change amount ⁇ ABS is performed using Quasi-CW laser (made by IPG Photonics Co., Ltd.) as a probe light source, an absorbance detection system having a monochromator and a detector, and excitation with a nitrogen laser (wavelength The light irradiation system was used, and the solution of the target compound was injected into a quartz cell with an optical path length of 1 mm.
  • Quasi-CW laser made by IPG Photonics Co., Ltd.
  • Tetracene-5,12-dione (1.50 g, 5.80 mmol) and tin powder (3.00 g) were placed in a 100 mL Schlenk tube, 35 mL of acetic acid was added, and the mixture was stirred for 1 hour while heating to 120 ° C.
  • Hydrochloric acid (35%, 11.5 M, 4 mL) was added and filtered while keeping the reaction solution at high temperature, then the filtrate was concentrated to half volume and allowed to cool to room temperature.
  • the resulting precipitate was collected by filtration and washed with pure water to obtain a pale yellow solid. By subjecting this pale yellow solid to recrystallization from hot ethanol, Intermediate 1 (5-tetracenone) as an ocher needle-like crystal was obtained in a yield of 894 mg (3.66 mmol) in a yield of 63%.
  • Example 1 Evaluation of Singlet Splitting Performance and Triplet Sensitizing Performance of Compound 1 Evaluation by Photoluminescence Quantum Yield A thin film of Compound 1 (the concentration of Compound 1 is 100% by weight on a quartz substrate by spin coating) And a thin film of ACRXTN (a thin film in which the concentration of Compound 1 is 0% by weight). Also, separately from this, various thin films were also formed by changing the concentration of Compound 1 to 6 wt%, 10 wt%, 20 wt%, 30 wt%, and 60 wt% by spin coating. The emission spectrum of each thin film formed by 371 nm excitation light is shown in FIG.
  • the photoluminescence quantum yield of the thin film of ACRXTN (the thin film with a concentration of 0 wt% of compound 1) was as high as 70%, whereas It was confirmed that the photoluminescence quantum yield decreases as the concentration is increased to 6 to 100% by weight. This is considered to be because the increase in the concentration of Compound 1 reduces the distance between the molecules of Compound 1 and promotes singlet division occurring between the molecules of Compound 1. Thus, this result indicates that Compound 1 is a singlet fission material, and indicates the usefulness as a triplet sensitizer.
  • the absorbance change amount ⁇ ABS is a value obtained by subtracting the absorbance ABS 0 of the solution before pump light irradiation from the absorbance ABS EX of the solution after pump light irradiation.
  • FIG. 5 shows that when a chloroform solution containing compound 1 at a concentration of 5 ⁇ 10 ⁇ 2 mol / L is irradiated with pump light at 10 ⁇ J / pulse, 15 ⁇ J / pulse or 20 ⁇ J / pulse.
  • FIG. 7 shows that Compound 1 is 1 ⁇ 10 ⁇ 3 mol / L, 1 ⁇ 10 ⁇ 2 mol / L, 2.5 ⁇ 10 ⁇ 2 mol / L, 5 ⁇ 10 ⁇ 2.
  • a transient absorption decay curve is shown when pump light is irradiated at 15 ⁇ J / pulse to each chloroform solution contained at a concentration of mol / L or 1 ⁇ 10 ⁇ 1 mol / L.
  • Compound 1 is 1 ⁇ 10 ⁇ 3 mol / L, 1 ⁇ 10 ⁇ 2 mol / L, 2.5 ⁇ 10 ⁇ 2
  • the absorbance change amount ⁇ ABS at 530 nm is the vertical axis
  • the excitation light intensity is the horizontal axis
  • the plotted correlation diagram is shown in FIG.
  • the triplet exciton generation efficiency IS ISC was calculated by setting the molar absorption coefficient ⁇ for pump light to 2793 L / (mol cm) and setting the optical path length L of the cell to 1 mm.
  • the scale of the vertical axis in FIG. 10 indicates the relative value obtained by standardizing ⁇ ISC at each concentration with ⁇ ISC at 1 ⁇ 10 ⁇ 3 mol / L as 1. As shown in FIG.
  • the triplet exciton generation efficiency ⁇ ISC of compound 1 improves as the compound concentration increases, and at the probe light wavelength of 530 nm, the triplet exciton at 1 ⁇ 10 ⁇ 1 mol / L generation efficiency [Phi ISC reached approximately 10 times the triplet exciton generation efficiency [Phi ISC at 1 ⁇ 10 -3 mol / L.
  • the fact that the triplet exciton generation efficiency IS ISC has been improved depending on the concentration of Compound 1 is that the intermolecular distance of Compound 1 becomes short due to the increase of the concentration of Compound 1 and occurs between molecules It shows that singlet splitting process (electron transfer) and triplet exciton generation via the singlet splitting process are promoted. From this, it could be confirmed that Compound 1 is useful as a singlet fission material and a triplet sensitizer.
  • the compounds of the present invention are useful as singlet fission materials and triplet sensitizers.
  • the triplet sensitizer of the present invention the efficiency of an organic device such as an organic light emitting element or an organic solar cell can be dramatically improved. For this reason, the present invention has high industrial applicability.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Electroluminescent Light Sources (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

L'invention concerne un composé représenté par la formule générale (1) qui est utile en tant que matériau à fission de singulet et en tant que sensibilisateur de triplet. R1 dans la formule générale (1) représente un groupe aryle substitué ou non substitué. L'un de R2 et R3 est un atome d'hydrogène, tandis que l'autre représente un groupe aryle substitué ou non substitué.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020250979A1 (fr) * 2019-06-14 2020-12-17 株式会社Ｋｙｕｌｕｘ Élément électroluminescent organique, corps de stratification et procédé électroluminescent

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11111458A (ja) * 1997-09-29 1999-04-23 Toyo Ink Mfg Co Ltd 有機エレクトロルミネッセンス素子材料およびそれを使用した有機エレクトロルミネッセンス素子
JP2006114844A (ja) * 2004-10-18 2006-04-27 Tdk Corp 有機ｅｌ素子材料の選択方法、有機ｅｌ素子の製造方法及び有機ｅｌ素子
JP2010537407A (ja) * 2007-08-13 2010-12-02 ユニバーシティ オブ サザン カリフォルニア 三重項ハーベストを用いた有機感光性光電子工学装置
JP2015536050A (ja) * 2012-09-26 2015-12-17 ザ リージェンツ オブ ザ ユニヴァシティ オブ ミシガン 無機太陽電池の効率を上昇させる励起子のエネルギー伝達
WO2016009203A1 (fr) * 2014-07-15 2016-01-21 Cambridge Enterprise Limited Dispositif et matériau composite de collecte de lumière
WO2016100754A1 (fr) * 2014-12-17 2016-06-23 The Trustees Of Columbia University In The City Of New York Fragmentation intramoléculaire quantitative dans des oligoacènes, matériaux, et leurs procédés d'utilisation

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11111458A (ja) * 1997-09-29 1999-04-23 Toyo Ink Mfg Co Ltd 有機エレクトロルミネッセンス素子材料およびそれを使用した有機エレクトロルミネッセンス素子
JP2006114844A (ja) * 2004-10-18 2006-04-27 Tdk Corp 有機ｅｌ素子材料の選択方法、有機ｅｌ素子の製造方法及び有機ｅｌ素子
JP2010537407A (ja) * 2007-08-13 2010-12-02 ユニバーシティ オブ サザン カリフォルニア 三重項ハーベストを用いた有機感光性光電子工学装置
JP2015536050A (ja) * 2012-09-26 2015-12-17 ザ リージェンツ オブ ザ ユニヴァシティ オブ ミシガン 無機太陽電池の効率を上昇させる励起子のエネルギー伝達
WO2016009203A1 (fr) * 2014-07-15 2016-01-21 Cambridge Enterprise Limited Dispositif et matériau composite de collecte de lumière
WO2016100754A1 (fr) * 2014-12-17 2016-06-23 The Trustees Of Columbia University In The City Of New York Fragmentation intramoléculaire quantitative dans des oligoacènes, matériaux, et leurs procédés d'utilisation

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
LIU, HEYUAN ET AL.: "A Covalently Linked Tetracene Trimer: Synthesis and Singlet Exciton Fission Property", ORGANIC LETTERS, vol. 19, 26 January 2017 (2017-01-26), pages 580 - 583, XP055566973, ISSN: 1523-7060 *
MASTRON, J. N. ET AL.: "Aqueous Colloidal Acene Nanoparticles: A New Platform for Studying Singlet Fission", THE JOURNAL OF PHYSICAL CHEMISTRY B, vol. 117, 2013, pages 15519 - 15526, XP055567054, ISSN: 1520-6106 *
MOU, WEIWEI ET AL.: "Nanoscopic mechanisms of singlet fission in amorphous molecular solid", APPLIED PHYSICS LETTERS, vol. 102, 2013, pages 173301, XP012172777, ISSN: 0003-6951 *
ROBERTS, S. T. ET AL.: "Efficient Singlet Fission Discovered in a Disordered Acene Film", JOURNAL OF THE AMERICAN CHEMICAL SOCEITY, vol. 134, 2012, pages 6388 - 6400, XP055566978, ISSN: 1520-5126 *
THOMPSON, N. J. ET AL.: "Magnetic field dependence of singlet fission in solutions of diphenyl tetracene", PHILOSOPHICAL TRANSACTIONS A, MATHEMATICAL , PHYSICAL AND ENGINEERING SCIENCES, vol. 373, no. 2044, 23 March 2014 (2014-03-23), pages 1 - 7, XP055566984, ISSN: 1364-503X *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020250979A1 (fr) * 2019-06-14 2020-12-17 株式会社Ｋｙｕｌｕｘ Élément électroluminescent organique, corps de stratification et procédé électroluminescent
JP2020205318A (ja) * 2019-06-14 2020-12-24 株式会社Ｋｙｕｌｕｘ 有機発光素子、積層体および発光方法
CN113795938A (zh) * 2019-06-14 2021-12-14 九州有机光材股份有限公司 有机发光元件、层叠体及发光方法
JP7337369B2 (ja) 2019-06-14 2023-09-04 株式会社Kyulux 有機発光素子、積層体および発光方法
CN113795938B (zh) * 2019-06-14 2024-05-28 九州有机光材股份有限公司 有机发光元件、层叠体及发光方法

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