Organic light-emitting device

Patent metadata

Field	Value
Publication number	US-2019296256-A1
Application number	US-201916364684-A
Country	US
Kind code	A1
Filing date	Mar 26, 2019
Priority date	Mar 26, 2018
Publication date	Sep 26, 2019
Grant date	—

Abstract

An organic light-emitting device which including a first electrode, a second electrode facing the first electrode, and an emission layer disposed between the first electrode and the second electrode, wherein an emission layer includes a first material, a second material, and a third material satisfying certain conditions.

First claim

What is claimed is:

1 . An organic light-emitting device comprising:
a first electrode; a second electrode facing the first electrode; and an emission layer disposed between the first electrode and the second electrode, wherein the emission layer comprises a first material, a second material, and a light-emitting material, the light-emitting material comprises a transition metal-containing phosphorescent material that emits blue light having a maximum emission wavelength in a range of about 420 nanometers to about 480 nanometers, the emission layer emits blue phosphorescence generated when an exciton of the transition metal-containing phosphorescent material transits from a triplet excited state to a ground state, the first material and the second material are different from each other, the first material and the second material form an exciplex, at least one of an absolute value of a difference between triplet energy (expressed in electron volts) of the first material and singlet energy (expressed in electron volts) of the exciplex and an absolute value of a difference between triplet energy (expressed in electron volts) of the second material and the singlet energy (expressed in electron volts) of the exciplex is about 0.1 electron volts or less, the triplet energy of the first material is calculated from a peak wavelength of a phosphorescence spectrum measured at 77 Kelvins with respect to a mixture of the first material and 2-MeTHF, the triplet energy of the second material is calculated from a peak wavelength of a phosphorescence spectrum measured at 77 Kelvins with respect to a mixture of the second material and 2-MeTHF, and the singlet energy of the exciplex is calculated from a peak wavelength of a fluorescence spectrum measured at room temperature with respect to a 50-nanometer-thick thin film formed by co-depositing the first material and the second material at a weight ratio of 5:5.

2 . The organic light-emitting device of claim 1 , wherein
photoluminescence quantum yield (PLQY) of the exciplex is about 0.12 or less, and the PLQY of the exciplex is evaluated by measuring PLQY of a 50-nanometer-thick thin film formed by co-depositing the first material and the second material at a weight ratio of 5:5.

3 . The organic light-emitting device of claim 1 , wherein
the singlet energy of the exciplex is in a range of about 2.80 electron volts to about 3.00 electron volts.

4 . The organic light-emitting device of claim 1 , wherein
the first material does not comprise an electron transport moiety, and the second material comprises at least one electron transport moiety.

5 . The organic light-emitting device of claim 4 , wherein
the absolute value of the difference between the triplet energy (expressed in electron volts) of the second material and the singlet energy (expressed in electron volts) of the exciplex is 0.1 electron volts or less.

6 . The organic light-emitting device of claim 4 , wherein
the triplet energy (expressed in electron volts) of the first material is higher than or equal to the singlet energy (expressed in electron volts) of the exciplex.

7 . The organic light-emitting device of claim 4 , wherein
the triplet energy (expressed in electron volts) of the second material is higher than or equal to the singlet energy (expressed in electron volts) of the exciplex.

8 . The organic light-emitting device of claim 1 , wherein
triplet energy of the light-emitting material is in a range of about 2.60 electron volts to about 2.80 electron volts, and the triplet energy of the light-emitting material is calculated from a peak wavelength of a phosphorescence spectrum measured at 77 Kelvins with respect to a mixture of the light-emitting material and 2-MeTHF.

9 . The organic light-emitting device of claim 1 , wherein
the first material comprises at least one π electron-depleted nitrogen-free cyclic group and does not comprise an electron transport moiety, the second material comprises at least one π electron-depleted nitrogen-free cyclic group and at least one electron transport moiety, and the electron transport moiety is selected from a cyano group, a π electron-depleted nitrogen-containing cyclic group, and a group represented by one of the following Formulae:

wherein, in the Formulae above, *, *′, and *″ each indicate a binding site to a neighboring atom.

10 . The organic light-emitting device of claim 1 , wherein
the first material comprises at least one selected from a compound represented by Formula H-1(1), a compound represented by Formula H-1(2), and a compound represented by Formula H-1(3):

wherein, in Formulae H-1(1) to H-1(3),
rings A 41 to A 44 are each independently a benzene group, a naphthalene group, an indene group, an indole group, a benzofuran group, a benzothiophene group, a benzosilole group, a fluorene group, a carbazole group, a dibenzofuran group, a dibenzothiophene group, or a dibenzosilole group,
X 41 is N-[(L 411 ) c411 -Z 411 ], C(Z 415 )(Z 416 ), O, or S,
X 42 is a single bond, N-[(L 412 ) c412 -Z 412 ], C(Z 417 )(Z 418 ), O, or S,
X 43 is N-[(L 413 ) c413 -Z 413 ], C(Z 419 )(Z 420 ), O, or S,
X 44 is a single bond, N-[(L 414 ) c414 -Z 414 ], C(Z 421 )(Z 422 ), O, or S,
L 401 and L 411 to L 414 are each independently selected from:
a single bond; and
a π electron-depleted nitrogen-free cyclic group unsubstituted or substituted with at least one selected from deuterium, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a triphenylenyl group, a biphenyl group, a terphenyl group, a tetraphenyl group, and —Si(Q 401 )(Q 402 )(Q 403 ),
a401 and c411 to c414 are each independently an integer from 1 to 10, wherein, when a401 is two or more, two or more groups L 401 are identical to or different from each other, when c411 is two or more, two or more groups L 411 are identical to or different from each other, when c412 is two or more, two or more groups L 412 are identical to or different from each other, when c413 is two or more, two or more groups L 413 are identical to or different from each other, and when c414 is two or more, two or more groups L 414 are identical to or different from each other,
Z 41 to Z 44 and Z 411 to Z 422 are each independently selected from:
hydrogen, deuterium, a C 1 -C 10 alkyl group, and a C 1 -C 10 alkoxy group; and
a π electron-depleted nitrogen-free cyclic group unsubstituted or substituted with at least one selected from deuterium, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a triphenylenyl group, a biphenyl group, a terphenyl group, a tetraphenyl group, and —Si(Q 401 )(Q 402 )(Q 403 ),
b41 to b44 are each independently 1, 2, 3, or 4, and
Q 401 to Q 403 are each independently hydrogen, deuterium, a C 1 -C 10 alkyl group, a C 1 -C 10 alkoxy group, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenyl group, a triphenylenyl group, a biphenyl group, a terphenyl group, or a tetraphenyl group.

11 . The organic light-emitting device of claim 10 , wherein
L 401 and L 411 to L 414 are ea

Assignees

• Samsung Electronics Co Ltd
• Samsung Sdi Co Ltd

Inventors

• Kim Joonghyuk
• Kang Hosuk
• Kim Sunghan
• Kim Jongsoo
• Son Youngmok
• Sim Myungsun
• Ihn Sooghang

Classifications

• C09K11/06 Primary

  containing organic luminescent materials · CPC title

• C09K2211/185

  of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd · CPC title

• C09K2211/1044

  containing two nitrogen atoms as heteroatoms · CPC title

• H01L51/0072

  Electricity · mapped topic

• H01L2251/558

  Electricity · mapped topic