Organic electroluminescent device

Patent metadata

Field	Value
Publication number	US-9434877-B2
Application number	US-201113582572-A
Country	US
Kind code	B2
Filing date	Feb 3, 2011
Priority date	Mar 6, 2010
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

The present invention relates to organic electro-luminescent devices which in a hole transport layer have a mixture of two or more materials.

First claim

The invention claimed is:

1. An organic electroluminescent device comprising anode, cathode, at least one emitting layer and at least one hole-transport layer, which is arranged between the anode and the emitting layer, where the hole-transport layer comprises a mixture of a material HTM-1 and a material HTM-2, wherein the HOMO of HTM-1 is at least 0.15 eV higher than the HOMO of HTM-2; with the proviso that neither material HTM-1 nor material HTM-2 is a metal complex and that the materials in the emitting layer and in the hole-transport layer are not all identical,
wherein HTM-1 is selected from compounds of the formulae (1) to (11) and (13) to (15),

where the following applies to the symbols and indices used:
Ar 1 is on each occurrence, identically or differently, a monovalent aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R 1 ; two groups Ar 1 here which are bonded to the same nitrogen atom, and/or a group Ar 2 and a group Ar 1 which are bonded to the same nitrogen atom is optionally linked to one another by a single bond or a bridge selected from the group consisting of B(R 1 ), C(R 1 ) 2 , Si(R 1 ) 2 , C═O, C═NR 1 , C═C(R 1 ) 2 , O, S, S═O, SO 2 , N(R 1 ), P(R 1 ) and P(═O)R 1 ;
Ar 2 is on each occurrence, identically or differently, a divalent, trivalent or tetravalent aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R 1 ;
R 1 is on each occurrence, identically or differently, H, D, F, Cl, Br, I, CHO, C(═O)Ar 3 , P(═O)(Ar 3 ) 2 , S(═O)Ar 3 , S(═O) 2 Ar 3 , CR 2 ═CR 2 Ar 3 , CN, NO 2 , Si(R 2 ) 3 , B(OR 2 ) 2 , B(R 2 ) 2 , B(N(R 2 ) 2 ) 2 , OSO 2 R 2 , a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a straight-chain alkenyl or alkynyl group having 2 to 40 C atoms or a branched or cyclic alkyl, alkenyl, alkynyl, alkoxy or thioalkoxy group having 3 to 40 C atoms, each of which is optionally substituted by one or more radicals R 2 , where one or more non-adjacent CH 2 groups is optionally replaced by R 2 C═CR 2 , C≡C, Si(R 2 ) 2 , Ge(R 2 ) 2 , Sn(R 2 ) 2 , C═O, C═S, C═Se, C═NR 2 , P(═O)(R 2 ), SO, SO 2 , NR 2 , O, S or CONR 2 and where one or more H atoms is optionally replaced by D, F, Cl, Br, I, CN or NO 2 , or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R 2 , or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R 2 , or a combination of these systems; two or more adjacent substituents R 1 here may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another;
Ar 3 is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 40 aromatic ring atoms, which is optionally substituted by one or more radicals R 2 ;
R 2 is on each occurrence, identically or differently, H, D, CN or an aliphatic, aromatic and/or heteroaromatic hydrocarbon radical having 1 to 20 C atoms, in which, in addition, H atoms is optionally replaced by D or F; two or more adjacent substituents R 2 here may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another;
L is a single bond or a divalent group selected from an alkylene group having 1 to 10 C atoms or an alkenylene or alkynylene group having 2 to 10 C atoms, each of which is optionally substituted by one or more radicals R 1 , an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which may in each case be substituted by one or more radicals R 1 , C═O, O, S or NR 1 or a combination of 2, 3, 4 or 5 of these groups;
X is on each occurrence, identically or differently, CR 1 or N, with the proviso that a maximum of two symbols X per ring stand for N and that X stands for C if a group L is bonded to this group X;
two adjacent groups X here may also be replaced by a group of the following formula (12):

the dashed bonds here indicate the linking of this unit to the carbazole derivative;
Y is on each occurrence, identically or differently, CR 1 or N, with the proviso that a maximum of two symbols Y per ring stand for N;
Z is selected on each occurrence, identically or differently, from the group consisting of C(R 1 ) 2 , N(R 1 ), N(Ar 1 ), O, S, B(R 1 ), Si(R 1 ) 2 , C═O, C═NR 1 , C═C(R 1 ) 2 , S═O, SO 2 , CR 1 —CR 1 , P(R 1 ) and P(═O)R 1 ;
W is, identically or differently on each occurrence, a single bond, C(R 1 ) 2 , NR 1 , O or S, where a maximum of one group W stands for a single bond; it is furthermore possible for a group W not to be present;
n is, identically or differently on each occurrence, 0 or 1, where at least one index n stands for 1;
m is, identically or differently on each occurrence, 0 or 1, where at least one index m stands for 1;
p is, identically or differently on each occurrence, 0, 1 or 2;
with the proviso that X in formula (15) stands for C if a group N(Ar 1 ) 2 , Ar 2 or a group W is bonded to this group X,
and wherein HTM-2 is selected from the group consisting of carbazole derivatives, carbazole derivatives containing condensed-on groups, compounds of the formula (15) in which all indices m are 0, diazaborole derivatives, and aromatic hydrocarbons optionally substituted by non-aromatic groups.

2. The organic electroluminescent device according to claim 1 , wherein the HOMO of HTM-1 is at least 0.25 eV higher than the HOMO of HTM-2.

3. The organic electroluminescent device according to claim 1 , wherein the HOMO of HTM-1 is at least 0.3 eV higher than the HOMO of HTM-2.

4. The organic electroluminescent device according to claim 1 , wherein the hole-transport layer comprising HTM-1 and HTM-2 consists only of the two materials HTM-1 and HTM-2.

5. The organic electroluminescent device according to claim 1 , wherein the mixing ratio of HTM-1 to HTM-2 is between 95:5 and 5:95, in each case based on the volume.

6. The organic electroluminescent device according to claim 1 , wherein the mixing ratio of HTM-1 to HTM-2 is between 85:15 and 40:60.

7. The organic electroluminescent device according to claim 1 , wherein the hole-transport layer comprising HTM-1 and HTM-2 is directly adjacent to the emitting layer or in that the hole-transport layer comprising HTM-1 and HTM-2 is arranged between two further hole-transport layers.

8. The organic electroluminescent device according to claim 1 , wherein the layer thickness of the hole-transport layer comprising HTM-1 and HTM-2 is between 5 and 300 nm.

9. The organic electroluminescent device according to claim 1 , wherein the layer thickness of the hole-transport layer comprising HTM-1 and HTM-2 is between 10 and 150 nm.

10. The organic electroluminescent device according to claim 1 , wherein the LUMO of HTM-2 is higher than the HOMO of HTM-1, and is at least 0.1 eV higher.

11. The organic electroluminescent device according to claim 1 , wherein the LUMO both of HTM-1 and also of HTM-2 are at least 0.2 eV higher than the LUMO of the matrix in the emitting layer, or, in the case of the use of a plurality of matrix materials, than the LUMO of the matrix material having the lowest LUMO.

Assignees

• Pflumm Christof
• Voges Frank
• Anémian Rémi Manouk
• Merck Patent Gmbh

Inventors

• Pflumm Christof
• Voges Frank
• Anémian Rémi Manouk

Classifications

• H05B33/22

  characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers · CPC title

• C09K11/06 Primary

  containing organic luminescent materials · CPC title

• C09B57/10

  Metal complexes of organic compounds not being dyes in uncomplexed form · CPC title

• C09B57/00

  Other synthetic dyes of known constitution · CPC title

• C09B57/008

  Triarylamine dyes containing no other chromophores · CPC title