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CN-115136339-B - Organic electroluminescent element, organic EL display device, and organic EL illumination

CN115136339BCN 115136339 BCN115136339 BCN 115136339BCN-115136339-B

Abstract

The invention provides an organic electroluminescent element, which comprises an anode, a cathode and an organic layer between the anode and the cathode on a substrate. The organic layer has a hole transport layer and a light emitting layer adjacent to the hole transport layer. At least one of the materials contained in the hole transport layer and at least one of the materials contained in the light emitting layer each have the same partial structure a shown by the following formula (31). The ring HA is a single ring or an aromatic heterocycle with 2-6 condensed rings and substituents. Ar 0 is a monovalent group in which 2 or more groups selected from the group consisting of an optionally substituted aromatic hydrocarbon group, an optionally substituted aromatic heterocyclic group, and an optionally substituted aromatic hydrocarbon group and an optionally substituted aromatic heterocyclic group are bonded to each other. n1 is 0 or an integer of not more than the number of substituents that Ar 0 can make on the ring HA.

Inventors

  • Kajima Yoshiko
  • LI YANJUN
  • NAKAI TOSHIMITSU
  • OKABE KAZUKI

Assignees

  • 三菱化学株式会社

Dates

Publication Date
20260505
Application Date
20210216
Priority Date
20200220

Claims (18)

  1. 1. An organic electroluminescent device having an anode, a cathode, and an organic layer between the anode and the cathode on a substrate, The organic layer has a hole transport layer and a light emitting layer adjacent to the hole transport layer, At least one of the materials contained in the hole transport layer and at least one of the materials contained in the light emitting layer each have the same partial structure a shown by the following formula (31), The partial structure A represented by the formula (31) is a structure represented by the following formula (35), The light-emitting layer comprises a low-molecular compound having the partial structure A, wherein the low-molecular compound is a compound with a molecular weight of 5000 or less represented by any one of the following formulas (10A-1) to (10A-3), , In the formula (31), The ring HA represents a single ring or an aromatic heterocycle having 3 or more and 60 or less carbon atoms which may have a substituent and is a condensed ring of 2 to 6, The benzene ring in the formula (31) may have a substituent, Ar 0 represents an aromatic hydrocarbon group having 6 or more and 60 or less carbon atoms which may have a substituent, an aromatic heterocyclic group having 3 or more and 60 or less carbon atoms which may have a substituent, or a monovalent group in which 2 or more groups selected from the group consisting of an aromatic hydrocarbon group having 6 or more and 60 or less carbon atoms which may have a substituent and an aromatic heterocyclic group having 3 or more and 60 or less carbon atoms which may have a substituent are bonded to each other, N1 represents 0 or an integer of not more than the number of substituents Ar 0 on the ring HA, When n1 is 2 or more, a plurality of Ar 0 may be the same or different, The substituents are selected from the following substituent group Z, , In the formula (35), the amino acid sequence of the compound, Ar 0 and n1 have the same meanings as Ar 0 and n1 in the formula (31), and the benzene ring in the formula (35) may have a substituent, X, Y each independently represents a C atom or an N atom, In the case of X, Y being a C atom, ar 0 may be bonded, The substituents are selected from the following substituent group Z, , In the steps (10A-1) to (10A-3), Xa 1 、Ya 1 and Za 1 each independently represent a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent or a divalent aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, Xa 2 、Ya 2 and Za 2 each independently represent a hydrogen atom, an aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, R 33 represents a hydrogen atom or a substituent, and a plurality of R 33 may be the same or different, Xa 1 、Ya 1 、Za 1 、Xa 2 、Ya 2 and Za 2 may have a substituent, R 33 as a substituent is a substituent represented by the substituent group Z or a crosslinkable group represented by the crosslinkable group K, G11', h11' and j11' each independently represent an integer of 0 to 5, In the case where g11', h11', j11' are 2 or more, the plurality of Xa 1 、Ya 1 、Za 1 may be the same or different, [ Substituent group Z ] A linear, branched or cyclic alkyl group having 1 to 24 carbon atoms; alkenyl having 2 to 24 carbon atoms; Alkynyl having 2 to 24 carbon atoms; an alkoxy group having 1 to 24 carbon atoms; an aryloxy group or a heteroaryloxy group having 4 or more carbon atoms and 24 or more carbon atoms; an alkoxycarbonyl group having 2 to 24 carbon atoms; a dialkylamino group having 2 to 24 carbon atoms; A diarylamino group having 10 to 36 carbon atoms; an arylalkylamino group having 7 to 36 carbon atoms; an acyl group having 2 to 24 carbon atoms; A halogen atom; haloalkyl having 1 to 12 carbon atoms; alkylthio groups having 1 to 24 carbon atoms; arylthio or heteroarylthio having 4 to 36 carbon atoms; Silyl groups having 2 to 36 carbon atoms; A siloxy group having 2 to 36 carbon atoms; Cyano group; an aromatic hydrocarbon group having 6 to 36 carbon atoms; an aromatic heterocyclic group having 3 to 36 carbon atoms; a monovalent aromatic group in which an aromatic hydrocarbon ring and an aromatic heterocyclic group are connected, and when the number of aromatic hydrocarbon rings or aromatic heterocyclic groups is plural, they may be the same or different, and have 8 or more carbon atoms and 36 or less carbon atoms; [ crosslinkable group K ] , R 21 ～R 23 each independently represents a hydrogen atom or an alkyl group having 6 or less carbon atoms, R 24 ～R 26 each independently represents an alkyl group having 6 or less carbon atoms or an alkoxy group having 6 or less carbon atoms, P represents an integer of 1 to 4, q represents an integer of 1 to 4, r represents an integer of 1 to 4, Ar 21 、Ar 22 each independently represents an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent, Ar 21 、Ar 22 may have the same substituents as the substituent group Z, "-" Is a bonding site.
  2. 2. The organic electroluminescent element according to claim 1, wherein at least one of a material having a partial structure a contained in the hole transporting layer and a material having a partial structure a contained in the light emitting layer has 2 or more partial structures a.
  3. 3. The organic electroluminescent element according to claim 1, wherein in the partial structure represented by the formula (35), X and Y are N atoms.
  4. 4. The organic electroluminescent element according to claim 1, wherein Ar 0 is a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzopyrene ring, A monovalent group comprising 2 to 10 rings selected from the group consisting of a ring, a triphenylene ring, an acenaphthene ring, a fluoranthene ring, a fluorene ring, and a ring selected from these, or a furan ring, a benzofuran ring, a thiophene ring, a benzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, Diazole ring, indole ring, carbazole ring, pyrroloimidazole ring, pyrrolopyrazole ring, pyrrolopyrrole ring, thienopyrrole ring, thienothiophene ring, furopyrrole ring, furofuran ring, thienofuran ring, benzisotropic ring An azole ring, a benzisothiazole ring, a benzimidazole ring, a pyridine ring, a pyrazine ring, a pyridazine ring, a pyrimidine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinoxaline ring, a phenanthridine ring, a perimidine ring, a quinazoline ring, a quinazolinone ring, a dibenzofuran ring, a dibenzothiophene ring, an indolocarbazole ring, a monovalent group of a phenanthroline ring, or a monovalent group obtained by connecting 2 to 10 of these.
  5. 5. The organic electroluminescent element according to any one of claims 1 to 4, wherein the material having a partial structure A contained in the hole transport layer is a polymer compound having a repeating unit represented by the following formula (1), , In the formula (1), the components are as follows, A represents a part of the structure a, G represents an aromatic hydrocarbon group which may have a substituent or an N atom, Ar 2 represents a divalent aromatic hydrocarbon group having 6 or more and 60 or less carbon atoms which may have a substituent, a divalent aromatic heterocyclic group having 3 or more and 60 or less carbon atoms which may have a substituent, or a divalent group formed by connecting 2 or more groups selected from the group consisting of a divalent aromatic hydrocarbon group having 6 or more and 60 or less carbon atoms which may have a substituent and a divalent aromatic heterocyclic group having 3 or more and 60 or less carbon atoms which may have a substituent directly or via a linking group, Ar 20 represents a divalent group in which a plurality of divalent aromatic hydrocarbon groups having 6 to 60 carbon atoms which may have a substituent or 2 or more divalent aromatic hydrocarbon groups having 6 to 60 carbon atoms which may have a substituent are bonded together, The substituent may be any one or a combination of the substituent group Z, an aralkyl group having 7 to 40 carbon atoms, or an aralkyl group having a heterocyclic ring having 4 to 37 carbon atoms.
  6. 6. The organic electroluminescent element according to claim 5, wherein G is a group composed of any one of a benzene ring which may have a substituent, a fluorene ring which may have a substituent, and a spirofluorene ring which may have a substituent.
  7. 7. The organic electroluminescent element according to claim 5, wherein G is a structure shown in the following scheme 1, , "-" Indicates a bonding site with Ar 20 .
  8. 8. The organic electroluminescent element according to claim 5, wherein the G is an N atom.
  9. 9. The organic electroluminescent element according to claim 8, wherein the repeating unit represented by the formula (1) is a repeating unit represented by any one of the following formulas (2) -1 to (2) -3, , In the formula (2) -1 to the formula (2) -3, A has the same meaning as A in the formula (1), Q represents-C (R 5 ）（R 6 ）-、-N（R 7 ) -or-C (R 11 ）（R 12 ）-C（R 13 ）（R 14 ) -, R 1 ～R 4 each independently represents an alkyl group which may have a substituent, an alkoxy group which may have a substituent or an aralkyl group which may have a substituent, R 5 ～R 7 and R 11 ～R 14 each independently represent an alkyl group which may have a substituent, an alkoxy group which may have a substituent, an aralkyl group which may have a substituent or an aromatic hydrocarbon group which may have a substituent, The substituent that may be provided is an alkyl group having 1 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, an aralkyl group having 7 to 60 carbon atoms, an aromatic hydrocarbon group having 6 to 60 carbon atoms, or a crosslinkable group, A. b are each independently an integer of 0 to 4, C1 to c5 are each independently integers of 0 to 3, Wherein at least one of c3 and c5 is 1 or more, D1 to d4 are each independently integers of 1 to 4, When a plurality of R 1 、R 2 、R 3 、R 4 are present in the repeating unit, R 1 、R 2 、R 3 、R 4 may be the same or different.
  10. 10. The organic electroluminescent element according to claim 9, wherein the crosslinkable group is a group selected from the group consisting of a crosslinkable group K, (Crosslinkable group K) , R 21 ～R 23 each independently represents a hydrogen atom or an alkyl group having 6 or less carbon atoms, R 24 ～R 26 each independently represents an alkyl group having 6 or less carbon atoms or an alkoxy group having 6 or less carbon atoms, P represents an integer of 1 to 4, q represents an integer of 1 to 4, r represents an integer of 1 to 4, Ar 21 、Ar 22 each independently represents an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent, Ar 21 、Ar 22 may have the same substituents as the substituent group Z, "-" Is a bonding site.
  11. 11. The organic electroluminescent element according to claim 9, wherein R 1 、R 2 in the formula (2) -1 and the formula (2) -2 is an alkyl group having 1 to 6 carbon atoms which may have the substituent, and R 3 、R 4 is an alkyl group having 1 to 12 carbon atoms which may have the substituent.
  12. 12. The organic electroluminescent element according to claim 9, wherein R 5 ～R 7 and R 11 ～R 14 in the formula (2) -1 are each independently an alkyl group having 1 to 24 carbon atoms which may have the substituent, an alkoxy group having 1 to 24 carbon atoms which may have the substituent, an aralkyl group having 7 to 60 carbon atoms which may have the substituent, or an aromatic hydrocarbon group having 6 to 60 carbon atoms which may have the substituent.
  13. 13. The organic electroluminescent element according to claim 5, wherein-Ar 20 -A in the formula (1) is represented by the following formula (15), , In the formula (15), the amino acid sequence of the compound, X, Y each independently represents a C atom or an N atom, the ring having X, Y and N corresponds to the ring HA in formula (31), Ar 1 represents a divalent aromatic hydrocarbon group having 6 or more and 60 or less carbon atoms which may have a substituent, or a divalent group in which 2 or more divalent aromatic hydrocarbon groups having 6 or more and 60 or less carbon atoms which may have a substituent are bonded to each other, and the substituent may be any one of the substituent groups Z or a combination thereof, Ar 3 、Ar 4 is a monovalent group in which 2 or more groups selected from an aromatic hydrocarbon group having 6 or more and 60 or less carbon atoms which may have a substituent, an aromatic heterocyclic group having 3 or more and 60 or less carbon atoms which may have a substituent, an aromatic hydrocarbon group having 6 or more and 60 or less carbon atoms which may have a substituent, and an aromatic heterocyclic group having 3 or more and 60 or less carbon atoms which may have a substituent are bonded to each other, and the substituent may be any one of the substituent groups Z or a combination thereof, Wherein in at least one of Ar 1 、Ar 3 、Ar 4 , the structure bonded to the ring HA is a benzene ring, * The bond site with G is shown.
  14. 14. The organic electroluminescent element according to claim 13, wherein Ar 3 and Ar 4 in the formula (15) each independently have a structure selected from a-1~a-4, b-1~b-9, c-1~c-5, d-1~d-17 and e-1~e-4 shown in the following scheme 2, , These structures may have a substituent, in the figure, "-" represents a bonding site to the ring HA, and in the case where "-" HAs a plurality of sites, any one represents a bonding site to the ring HA, R 3A and R 3B are each independently a linear, branched or cyclic alkyl group which may have a substituent, The substituent group Z may be any one or a combination of the substituents.
  15. 15. The organic electroluminescent element according to claim 13, wherein-Ar 20 -A in the formula (1) is represented by the following formula (16), , In the formula (16), the amino acid sequence of the compound, X, Y are as defined for X, Y in formula (15), The rings X, Y and N correspond to the ring HA as in formula (15), Ar 1' represents a residue directly bonded or when the structure of Ar 1 bonded to the ring HA in the formula (15) is a benzene ring, Ar 3' 、Ar 4' represents a hydrogen atom or a residue when the structure of Ar 3 、Ar 4 bonded to the ring HA in the formula (15) is a benzene ring.
  16. 16. The organic electroluminescent element according to claim 5, wherein the material having a partial structure A contained in the hole transport layer further has a repeating unit represented by the following formula (3), , In the formula (3), the amino acid sequence of the compound, Ar 13 represents an optionally substituted aromatic hydrocarbon group or an optionally substituted aromatic heterocyclic group not containing part of the structure A, Ar 14 represents a divalent aromatic hydrocarbon group which may have a substituent, a divalent aromatic heterocyclic group which may have a substituent, or a divalent group in which 2 or more groups selected from the group consisting of a divalent aromatic hydrocarbon group which may have a substituent and a divalent aromatic heterocyclic group which may have a substituent are bonded directly or via a linking group.
  17. 17. An organic EL display device comprising the organic electroluminescent element according to any one of claims 1 to 4.
  18. 18. An organic EL lighting device comprising the organic electroluminescent element according to any one of claims 1 to 4.

Description

Organic electroluminescent element, organic EL display device, and organic EL illumination Technical Field The present invention relates to an organic electroluminescent element, an organic EL display device including the same, and an organic EL illumination. Background Examples of the method for forming the organic layer in the organic electroluminescent element include a vacuum vapor deposition method and a wet film formation method. The vacuum vapor deposition method is advantageous in that it is easy to improve charge injection from the anode and/or the cathode and to seal excitons in the light-emitting layer. On the other hand, the wet film forming method has advantages that a vacuum process is not required, an increase in area is easy to achieve, and a layer containing a plurality of materials having various functions can be easily formed by using a coating liquid obtained by mixing a plurality of materials having various functions. However, since wet film forming methods are difficult to laminate, the driving stability is inferior to that of elements obtained by vacuum vapor deposition methods, and the practical level is not achieved except for a part of them. In order to laminate by a wet film forming method, a charge transporting polymer having a crosslinkable group is desired, and development thereof is underway. For example, patent document 1 discloses an organic EL manufactured by stacking a plurality of layers by a wet film forming method. Patent document 1 International publication No. 2013/080696 However, lamination by the conventional wet film forming method has a problem in terms of hole transport efficiency between the layers to be laminated, for example, between the light-emitting layer and the hole transport layer. Patent document 1 discloses a host compound as a light-emitting layer, and from the viewpoint of charge transport, a host compound having a structure common to a compound constituting a hole-transporting layer is preferable. However, the disclosed structure is a very small part, and it is not clear what other structure is capable of exerting this effect. In addition, there is room for research concerning the effects of luminance, driving life, and the like as a whole of the organic electroluminescent element. Disclosure of Invention The invention provides an organic electroluminescent element with high brightness and long driving life. The present inventors have found that in an organic electroluminescent element having an anode, a cathode, and an organic layer between the anode and the cathode on a substrate, the organic layer has a hole transport layer and a light-emitting layer adjacent to the hole transport layer, and both the material contained in the hole transport layer and the material contained in the light-emitting layer have a specific structure, which is an aromatic heterocycle having an electron-withdrawing structure and containing a single ring or 2 to 6 condensed rings, as a material of a partial structure, the performance of the organic electroluminescent element is improved. The gist of the invention is as shown in the following [1] to [19 ]. [1] An organic electroluminescent element comprising an anode, a cathode, and an organic layer between the anode and the cathode on a substrate, wherein the organic layer comprises a hole transport layer and a light-emitting layer adjacent to the hole transport layer, and at least one of the materials contained in the hole transport layer and at least one of the materials contained in the light-emitting layer each have the same partial structure A represented by the following formula (31). (In the formula (31), The ring HA represents a single ring or an aromatic heterocycle having 2 to 6 condensed rings and optionally having a substituent. The benzene ring in the formula (31) may have a substituent. Ar 0 represents an optionally substituted aromatic hydrocarbon group, an optionally substituted aromatic heterocyclic group, or a monovalent group in which 2 or more groups selected from the optionally substituted aromatic hydrocarbon group and the optionally substituted aromatic heterocyclic group are bonded. N1 represents 0 or an integer of not more than the number of substituents Ar 0 on the ring HA. When n1 is 2 or more, a plurality of Ar 0 may be the same or different [2] The organic electroluminescent element according to [1], wherein at least one of the material having the partial structure A contained in the hole transport layer and the material having the partial structure A contained in the light emitting layer has 2 or more partial structures A. [3] The organic electroluminescent element according to [1] or [2], wherein the partial structure A represented by the above formula (31) is a structure represented by any one of the following formulas (33) to (35). In the formulae (33) to (35), Ar 0 and n1 have the same meanings as Ar 0 and n1 in formula (31). The benzene ring in the formulae (33) to (35) may have a substit