U.S. patent application number 13/677710 was filed with the patent office on 2013-05-23 for organic electroluminescent element, compound for use in the element, and light emitting device, display device, and illumination device using the element.
This patent application is currently assigned to UDC Ireland Limited. The applicant listed for this patent is UDC Ireland Limited. Invention is credited to Yuki Hirai, Tetsu Kitamura, Tianhua Ouyang, Wataru Sotoyama, Koji Takaku, Toru Watanabe, Yasunori Yonekuta, Katsuyuki Youfu.
Application Number | 20130126835 13/677710 |
Document ID | / |
Family ID | 48425930 |
Filed Date | 2013-05-23 |
United States Patent
Application |
20130126835 |
Kind Code |
A1 |
Takaku; Koji ; et
al. |
May 23, 2013 |
Organic Electroluminescent Element, Compound for Use in the
Element, and Light Emitting Device, Display Device, and
Illumination Device Using the Element
Abstract
The disclosure relates to organic electroluminescent elements,
compounds for use in the elements, and devices using the elements,
which include a compound represented by the following General
Formula (1): ##STR00001## where R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represents a hydrogen atom, which may be
a deuterium atom, or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5, R.sup.9 and
R.sup.10 each independently represents a hydrogen atom or a
substituent, L.sup.1 represents a divalent linking group, DG.sup.1
represents a donor group, and n1 represents 1 or 2, and where
R.sup.1 to R.sup.3, R.sup.5 to R.sup.10, L.sup.1, and DG.sup.1 are
not bound to each other to form a ring.
Inventors: |
Takaku; Koji; (Kanagawa,
JP) ; Yonekuta; Yasunori; (Kanagawa, JP) ;
Sotoyama; Wataru; (Kanagawa, JP) ; Youfu;
Katsuyuki; (Kanagawa, JP) ; Hirai; Yuki;
(Kanagawa, JP) ; Kitamura; Tetsu; (Kanagawa,
JP) ; Watanabe; Toru; (Kanagawa, JP) ; Ouyang;
Tianhua; (Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
UDC Ireland Limited; |
Dublin |
|
IE |
|
|
Assignee: |
UDC Ireland Limited
Dublin
IE
|
Family ID: |
48425930 |
Appl. No.: |
13/677710 |
Filed: |
November 15, 2012 |
Current U.S.
Class: |
257/40 ;
564/426 |
Current CPC
Class: |
H01L 2251/308 20130101;
C07D 213/74 20130101; C07D 263/48 20130101; C07D 307/66 20130101;
C07D 307/91 20130101; C07C 2603/50 20170501; H01L 51/0061 20130101;
C07D 239/42 20130101; C07D 493/04 20130101; C07C 211/54 20130101;
C07D 241/20 20130101; C07D 333/36 20130101; C07D 401/10 20130101;
H01L 51/006 20130101; H01L 51/0065 20130101; H01L 51/0054 20130101;
H01L 51/0068 20130101; C07D 495/04 20130101; H01L 51/0058 20130101;
H01L 51/0067 20130101; C07C 211/58 20130101 |
Class at
Publication: |
257/40 ;
564/426 |
International
Class: |
H01L 51/00 20060101
H01L051/00; C07C 211/54 20060101 C07C211/54 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 18, 2011 |
JP |
JP2011-252533 |
Claims
1. An organic electroluminescent element comprising: a substrate; a
pair of electrodes including an anode and a cathode, disposed on
the substrate; and an organic layer disposed between the
electrodes, wherein the organic layer contains a compound
represented by the following General Formula (1), ##STR00081##
wherein, in General Formula (1), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represents a hydrogen atom, which may be
a deuterium atom, or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5, R.sup.9 and
R.sup.10 each independently represents a hydrogen atom or a
substituent, L.sup.1 represents a divalent linking group, DG.sup.1
represents a donor group, and n1 represents 1 or 2, and wherein
R.sup.1 to R.sup.3, R.sup.5 to R.sup.10, L.sup.1, and DG.sup.1 are
not bound to each other to form a ring.
2. The organic electroluminescent element according to claim 1,
wherein the compound represented by the General Formula (1) is a
compound represented by the following General Formula (2),
##STR00082## wherein, in General Formula (2), R.sup.1 to R.sup.3
and R.sup.6 to R.sup.8 each independently represents a hydrogen
atom, which may be a deuterium atom, or a substituent with a
Hammett substituent constant .sigma..sub.p value of -0.15 or more,
R.sup.5 and R.sup.10 each independently represents a hydrogen atom
or a substituent, L.sup.1 and L.sup.2 each independently represents
a divalent linking group, DG.sup.1 and DG.sup.2 each independently
represents a donor group, and n1 and n2 each independently
represents 1 or 2, and wherein R.sup.1 to R.sup.3, R.sup.5 to
R.sup.8, R.sup.10, L.sup.1, L.sup.2, DG.sup.1 and DG.sup.2 are not
bound to each other to form a ring.
3. The organic electroluminescent element according to claim 1,
wherein, in the General Formula (1), the donor group represents
--NY.sup.1Y.sup.2, --OY.sup.3 or --SY.sup.4, where Y.sup.1 to
Y.sup.4 each independently represents an alkyl group, an aryl group
or a heteroaryl group, and which may have further substituents, or
be represented by following General Formula (A), ##STR00083##
wherein, in General Formula (A), X.sup.A and X.sup.B each
independently represents O, S or NY.sup.15, R.sup.15 to R.sup.17
each independently represents a hydrogen atom, an alkyl group, a
silyl group, an aryl group, a heteroaryl group,
--NY.sup.11Y.sup.12, --OY.sup.13 or --SY.sup.14, where Y.sup.11 to
Y.sup.15 each independently represents an alkyl group, an aryl
group or a heteroaryl group, and which may have further
substituents.
4. The organic electroluminescent element according to claim 2,
wherein the compound represented by the General Formula (2) is a
compound represented by the following General Formula (3),
##STR00084## wherein, in General Formula (3), R.sup.1 to R.sup.3
and R.sup.6 to R.sup.2 each independently represents a hydrogen
atom, which may be a deuterium atom, or a substituent with a
Hammett substituent constant .sigma..sub.p value of -0.15 or more,
R.sup.5 and R.sup.10 each independently represents a hydrogen atom
or a substituent, L.sup.1 and L.sup.2 each independently represents
a divalent linking group, R.sup.11 to R.sup.14 each independently
represents an alkyl group, an aryl group or a heteroaryl group, and
n1 and n2 each independently represents 1 or 2, and wherein R.sup.1
to R.sup.3, R.sup.5 to R.sup.8, R.sup.10 to R.sup.14, L.sup.1 and
L.sup.2 are not bound to each other to form a ring.
5. The organic electroluminescent element according to claim 2,
wherein in the General Formula (2) L.sup.1 and L.sup.2 each
independently represents an arylene group or a heteroarylene
group.
6. The organic electroluminescent element according to claim 5,
wherein the substituent included in the arylene group or the
heteroarylene group each independently represented by L.sup.1 and
L.sup.2 is only a substituent with a Hammett substituent constant
.sigma..sub.p value of less than 0.1.
7. The organic electroluminescent element according to claim 4,
wherein the compound represented by the General Formula (3) is a
compound represented by any of the following General Formulae (4)
to (7), ##STR00085## wherein, in General Formula (4), R.sup.1 to
R.sup.3 and R.sup.6 to R.sup.8 each independently represents a
hydrogen atom, which may be a deuterium atom, or a substituent with
a Hammett substituent constant .sigma..sub.p value of -0.15 or
more, R.sup.5 and R.sup.10 each independently represents a hydrogen
atom or a substituent, R.sup.11 to R.sup.14 each independently
represents an alkyl group, an aryl group or a heteroaryl group,
A.sup.1 to A.sup.8 each independently represents CRz, wherein two
adjacent CRzs may jointly form a five- or a six-membered ring, or
N, and Rz represents a hydrogen atom or a substituent, wherein
R.sup.1 to R.sup.3, R.sup.5 to R.sup.8, R.sup.10 to R.sup.14 and
A.sup.1 to A.sup.8 are not bound to each other to form a ring,
##STR00086## wherein, in General Formula (5), R.sup.1 to R.sup.3
and R.sup.6 to R.sup.8 each independently represents a hydrogen
atom, which may be a deuterium atom, or a substituent with a
Hammett substituent constant .sigma..sub.p value of -0.15 or more,
R.sup.5 and R.sup.10 each independently represents a hydrogen atom
or a substituent, R.sup.11 to R.sup.14 each independently
represents an alkyl group, an aryl group or a heteroaryl group,
X.sup.1 to X.sup.6 each independently represents CRz, wherein two
adjacent CRzs may jointly form a five- or a six-membered ring,
--N.dbd., NRy, O or S, and Rz and Ry each independently represents
a hydrogen atom or a substituent, wherein R.sup.1 to R.sup.3,
R.sup.5 to R.sup.8, R.sup.10 to R.sup.14 and X.sup.1 to X.sup.6 are
not bound to each other to form a ring, ##STR00087## wherein, in
General Formula (6), R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 each
independently represents a hydrogen atom, which may be a deuterium
atom, or a substituent with a Hammett substituent constant
.sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10 each
independently represents a hydrogen atom or a substituent, R.sup.11
to R.sup.14 each independently represents an alkyl group, an aryl
group or a heteroaryl group, X.sup.11, X.sup.13, X.sup.14 and
X.sup.16 to X.sup.20 each independently represents CRz, wherein two
adjacent CRzs may jointly form a five- or a six-membered ring,
--N.dbd., NRy, O or S, and Rz and Ry each independently represents
a hydrogen atom or a substituent, wherein R.sup.1 to R.sup.3,
R.sup.5 to R.sup.8, R.sup.10 to R.sup.14, X.sup.11, X.sup.13,
X.sup.14 and X.sup.16 to X.sup.20 are not bound to each other to
form a ring), ##STR00088## wherein, in General Formula (7), R.sup.1
to R.sup.3 and R.sup.6 to R.sup.8 each independently represents a
hydrogen atom, which may be a deuterium atom, or a substituent with
a Hammett substituent constant .sigma..sub.p value of -0.15 or
more, R.sup.5 and R.sup.10 each independently represents a hydrogen
atom or a substituent, R.sup.11 to R.sup.14 each independently
represents an alkyl group, an aryl group or a heteroaryl group,
R.sup.18 to R.sup.21 each independently represents a hydrogen atom,
a fluorine atom, an alkyl group, a silyl group, an aryl group, a
heteroaryl group, --NY.sup.21Y.sup.22, --OY.sup.23 or --SY.sup.24,
wherein Y.sup.21 to Y.sup.24 each independently represents an alkyl
group, an aryl group or a heteroaryl group, and which may have
further substituents, X.sup.31, X.sup.33, X.sup.34 and X.sup.36 to
X.sup.40 each independently represents CRz, wherein two adjacent
CRzs may jointly form a five- or a six-membered ring, --N.dbd.,
NRy, O or S, and Rz and Ry each independently represents a hydrogen
atom or a substituent, wherein R.sup.1 to R.sup.3, R.sup.5 to
R.sup.8, R.sup.10 to R.sup.14, R.sup.18 to R.sup.21, X.sup.31,
X.sup.33, X.sup.34 and X.sup.36 to X.sup.40 are not bound to each
other to form a ring.
8. The organic electroluminescent element according to claim 1,
wherein in the General Formula (1) R.sup.1 to R.sup.3 and R.sup.6
to R.sup.8 each independently represents a hydrogen atom, which may
be a deuterium atom, an alkyl group, an aryl group, a heteroaryl
group, a silyl group, an alkoxy group, an alkylthio group, an
aryloxy group, an arylthio group, a halogen atom or a cyano group,
and which may have further substituents.
9. The organic electroluminescent element according to claim 1,
wherein the organic electroluminescent element comprises a light
emitting layer including an anthracene-based host material.
10. The organic electroluminescent element according to claim 1,
wherein the organic electroluminescent element comprises a light
emitting layer formed by a vacuum deposition process.
11. The organic electroluminescent element according to claim 1,
wherein the organic electroluminescent element comprises a light
emitting layer formed by a wet process.
12. A light emitting device comprising the organic
electroluminescent element according to claim 1.
13. A display device comprising the organic electroluminescent
element according to claim 1.
14. An illumination device comprising the organic
electroluminescent element according to claim 1.
15. A compound represented by the following General Formula (1),
##STR00089## wherein, in General Formula (1), R.sup.1 to R.sup.3
and R.sup.6 to R.sup.8 each independently represents a hydrogen
atom, which may be a deuterium atom, or a substituent with a
Hammett substituent constant .sigma..sub.p value of -0.15 or more,
R.sup.5, R.sup.9 and R.sup.10 each independently represents a
hydrogen atom or a substituent, L.sup.1 represents a divalent
linking group, DG.sup.1 represents an electron donating group, and
n1 represents 1 or 2, wherein R.sup.1 to R.sup.3, R.sup.5 to
R.sup.10, L.sup.1, and DG.sup.1 are not bound to each other to form
a ring.
16. The compound according to claim 15, wherein in the General
Formula (1) R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 each
independently represents a hydrogen atom, which may be a deuterium
atom, an alkyl group, an aryl group, a heteroaryl group, a silyl
group, an alkoxy group, an alkylthio group, an aryloxy group, an
arylthio group, a halogen atom or a cyano group, and which may have
further substituents.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to Japanese
Patent Application No. 2011-252533, filed Nov. 18, 2011, which is
incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to organic electroluminescent
elements, and compounds usable therefor. The present invention also
relates to light emitting devices, display devices, and
illumination devices using the organic electroluminescent
elements.
BACKGROUND ART
[0003] Since organic electroluminescent elements (which may
hereinafter also be referred to as "elements" or "organic EL
elements") are capable of high-luminance light emitting using low
voltage driving, they have been actively researched and developed.
The organic electroluminescent elements have a pair of electrodes
and an organic layer between the pair of electrodes, and utilize,
for light emitting, energy of the exciton generated as a result of
recombination of the electron injected from the cathode and the
hole injected from the anode in the organic layer. The organic
electroluminescent elements can provide elements having diverse
light emitting wavelengths, and since they have a high response
speed and are relatively thin and light-weight, it is expected that
they can be employed in a wide range of applications. Among these,
it is important to develop an organic electroluminescent element
having high color purity and luminous efficiency in light of the
applications in full-color displays and the like, and the outcomes
have been reported of various research and development studies up
to now.
[0004] Compounds having a pyrene ring skeleton are known as
excellent blue fluorescent material, and represent an example of
the material of such organic electroluminescent elements. Among
such compounds, many 1,6-substituted pyrenes are known as examples
of light emitting materials (see, for example, JP-A-2006-298793,
JP-A-2004-204238, and KR10-2011-0057008).
[0005] JP-A-2006-298793 describes pyrene compounds having
diphenylamino group-substituted phenyl groups across the pyrene
ring on the long axis (positions 1, 2, 3, 6, 7, and 8) of the
pyrene ring. It is disclosed in the Examples of this publication
that a high emission-luminance, high heat-resistance, and long-life
organic EL element having excellent high-temperature preservability
could be produced when a pyrene compound having diphenylamino
group-substituted phenyl groups at positions 1 and 6 of the pyrene
ring was used as the dopant of a light emitting layer.
[0006] JP-A-2004-204238 describes pyrene compounds having
substituted amino groups such as diphenylamino groups across the
ring on the long axis (positions 1, 2, 3, 6, 7, and 8). It is
disclosed in the Examples of this publication that an organic EL
element having excellent blue color purity and luminous efficiency
could be produced when a pyrene compound having diphenylamino
groups at positions 1 and 6 of the pyrene ring was used as the
dopant of a light emitting layer.
[0007] KR10-2011-0057008 describes pyrene compounds, similar to
those described in JP-A-2004-204238, having substituted amino
groups such as diphenylamino groups across the ring on the long
axis (positions 1, 2, 3, 6, 7, and 8).
[0008] On the other hand, there are not many known examples of
pyrene compounds substituted at positions 4 and 9 or positions 4
and 10. For example, JP-A-2009-283899 describes pyrene compounds
having 2-phenylnaphthalene and other aryl groups or heteroaryl
groups across the ring on the short axis (positions 4, 5, 9, and
10). However, the only example in which the pyrene compounds are
used in the Examples of this publication is one in which a compound
having a 2-phenylnaphtyl group at pyrene position 4 and a terphenyl
group at position 9 is used as a host material of a light emitting
layer in combination with a green-emitting material. Further,
JP-A-2009-283899 merely describes host materials having a
2-phenylnaphthalene structure as being desirable, and does not
describe preferred specific light emitting material structures or
preferred specific substitution positions.
[0009] Under these circumstances, the present inventors studied the
pyrene compounds described in the foregoing publications by using
these compounds as light emitting materials of organic
electroluminescent elements, and found that the pyrene compounds
described in JP-A-2006-298793 and JP-A-2004-204238 had longer
wavelengths, and were unable to realize high blue color purity in
an organic electroluminescent element.
[0010] It was also found that the pyrene compounds described in
KR10-2011-0057008, and the compounds described in JP-A-2009-283899
did not have sufficient performance (including luminous efficiency)
as light emitting material, and had poor chromaticity.
SUMMARY OF THE INVENTION
[0011] Accordingly, there is a need for an organic
electroluminescent element that has sufficient luminous efficiency
and excellent chromaticity.
[0012] The present inventors conducted intensive studies to solve
the foregoing problems, and found that pyrene compounds having
substituents across the pyrene ring on the long axis (for example,
positions 1 and 6) of the pyrene ring has the tendency to have
insufficient chromaticity at longer wavelengths, whereas pyrene
compounds having substituents across the ring on the short axis
(for example, positions 4 and 9, and positions 4 and 10) has short
wavelengths, and can provide sufficient chromaticity.
[0013] Upon further studies, the present inventors found that
sufficient performance as light emitting material can be imparted
when a pyrene compound does not have an electron donating group in
the substituents across the pyrene ring on the long axis of the
pyrene ring, but has an electron donating substituent in the
substituents across the pyrene ring on the short axis of the pyrene
ring. It was also found that high heat resistance can be imparted
when no fused ring structure is formed by the binding of the
substituents across the pyrene ring on the short axis of the pyrene
ring and any other substituent of the pyrene ring.
[0014] The present invention provides specific means to solve the
foregoing problems, as follows.
[0015] [1] An organic electroluminescent element comprising:
[0016] a substrate;
[0017] a pair of electrodes including an anode and a cathode,
disposed on the substrate; and
[0018] an organic layer disposed between the electrodes,
[0019] wherein the organic layer contains a compound represented by
the following General Formula (1),
##STR00002##
(wherein, in General Formula (1), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represent a hydrogen atom (including a
deuterium atom) or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5, R.sup.9 and
R.sup.10 each independently represent a hydrogen atom or a
substituent, L.sup.1 represents a divalent linking group, DG.sup.1
represents a donor group, and n1 represents 1 or 2, however,
R.sup.1 to R.sup.3, R.sup.5 to R.sup.10, L.sup.1, and DG.sup.1 are
not bound to each other to form a ring).
[0020] [2] It is preferable in the organic electroluminescent
element according to [1] that the compound represented by the
General Formula (1) be a compound represented by following General
Formula (2),
##STR00003##
(wherein, in General Formula (2), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.9 each independently represent a hydrogen atom (including a
deuterium atom) or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
L.sup.1 and L.sup.2 each independently represent a divalent linking
group, DG.sup.1 and DG.sup.2 each independently represent a donor
group, and n1 and n2 each independently represent 1 or 2, however,
R.sup.1 to R.sup.3, R.sup.5 to R.sup.8, R.sup.10, L.sup.1, L.sup.2,
DG.sup.1 and DG.sup.2 are not bound to each other to form a
ring).
[0021] [3] It is preferable in the organic electroluminescent
element according to [1] or [1] that, in the General Formulae (1)
and (2), the donor group represent --NY.sup.1Y.sup.2, --OY.sup.3 or
--SY.sup.4 (Y.sup.1 to Y.sup.4 each independently represent an
alkyl group, an aryl group or a heteroaryl group, and any of these
may have further substituents), or be represented by following
General Formula (A),
##STR00004##
(wherein, in General Formula (A), X.sup.A and X.sup.B each
independently represent O, S or NY.sup.15, R.sup.15 to R.sup.17
each independently represent a hydrogen atom, an alkyl group, a
silyl group, an aryl group, a heteroaryl group,
--NY.sup.11Y.sup.12, --OY.sup.13 or --SY.sup.14 (Y.sup.11 to
Y.sup.15 each independently represent an alkyl group, an aryl group
or a heteroaryl group, and any of these may have further
substituents)).
[0022] [4] It is preferable in the organic electroluminescent
element according to [2] or [3] that the compound represented by
the General Formula (2) be a compound represented by following
General Formula (3),
##STR00005##
(wherein, in General Formula (3), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represent a hydrogen atom (including a
deuterium atom) or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
L.sup.1 and L.sup.2 each independently represent a divalent linking
group, R.sup.11 to R.sup.14 each independently represent an alkyl
group, an aryl group or a heteroaryl group, and n1 and n2 each
independently represent 1 or 2, however, R.sup.1 to R.sup.3,
R.sup.5 to R.sup.8, R.sup.10 to R.sup.14, L.sup.1 and L.sup.2 are
not bound to each other to form a ring).
[0023] [5] It is preferable in the organic electroluminescent
element according to any one of [1] to [4] that, in the General
Formulae (1) to (3), L.sup.1 and L.sup.2 each independently
represent an arylene group or a heteroarylene group.
[0024] [6] It is preferable in the organic electroluminescent
element according to [5] that the substituent included in the
arylene group or the heteroarylene group each independently
represented by L.sup.1 and L.sup.2 be only a substituent with a
Hammett substituent constant .sigma..sub.p value of less than
0.1.
[0025] [7] It is preferable in the organic electroluminescent
element according to any one of [4] to [6] that the compound
represented by the General Formula (3) be a compound represented by
any of following General Formulae (4) to (7),
##STR00006##
(wherein, in General Formula (4), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represent a hydrogen atom (including a
deuterium atom) or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
R.sup.11 to R.sup.14 each independently represent an alkyl group,
an aryl group or a heteroaryl group, A.sup.1 to A.sup.8 each
independently represent CRz (two adjacent CRz's may jointly form a
five- or a six-membered ring) or N, and Rz represents a hydrogen
atom or a substituent, however, R.sup.1 to R.sup.3, R.sup.5 to
R.sup.8, R.sup.10 to R.sup.14 and A.sup.1 to A.sup.8 are not bound
to each other to form a ring),
##STR00007##
(wherein, in General Formula (5), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represent a hydrogen atom (including a
deuterium atom) or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
R.sup.11 to R.sup.14 each independently represent an alkyl group,
an aryl group or a heteroaryl group, X.sup.1 to X.sup.6 each
independently represent CRz (two adjacent CRz's may jointly form a
five- or a six-membered ring), --N.dbd., NRy, O or S, and Rz and Ry
each independently represent a hydrogen atom or a substituent,
however, R.sup.1 to R.sup.3, R.sup.5 to R.sup.8, R.sup.10 to
R.sup.14 and X.sup.1 to X.sup.6 are not bound to each other to form
a ring),
##STR00008##
(wherein, in General Formula (6), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represent a hydrogen atom (including a
deuterium atom) or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
R.sup.11 to R.sup.14 each independently represent an alkyl group,
an aryl group or a heteroaryl group, X.sup.11, X.sup.13, X.sup.14
and X.sup.16 to X.sup.20 each independently represent CRz (two
adjacent CRz's may jointly form a five- or a six-membered ring),
--N.dbd., NRy, O or S, and Rz and Ry each independently represent a
hydrogen atom or a substituent, however, R.sup.1 to R.sup.3,
R.sup.5 to R.sup.8, R.sup.10 to R.sup.14, X.sup.11, X.sup.13,
X.sup.14 and X.sup.16 to X.sup.20 are not bound to each other to
form a ring),
##STR00009##
(wherein, in General Formula (7), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represent a hydrogen atom (including a
deuterium atom) or a substituent with a Hammett substituent
constant .sub.p value of -0.15 or more, R.sup.5 and R.sup.10 each
independently represent a hydrogen atom or a substituent, R.sup.11
to R.sup.14 each independently represent an alkyl group, an aryl
group or a heteroaryl group, R.sup.18 to R.sup.21 each
independently represent a hydrogen atom, a fluorine atom, an alkyl
group, a silyl group, an aryl group, a heteroaryl group,
--NY.sup.21Y.sup.22, --OY.sup.23 or --SY.sup.24 (Y.sup.21 to
Y.sup.24 each independently represent an alkyl group, an aryl group
or a heteroaryl group), and all of these may have further
substituents, X.sup.31, X.sup.33, X.sup.34 and X.sup.36 to X.sup.40
each independently represent CRz (two adjacent CRz's may jointly
form a five- or a six-membered ring), --N.dbd., NRy, O or S, and Rz
and Ry each independently represent a hydrogen atom or a
substituent, however, R.sup.1 to R.sup.3, R.sup.5 to R.sup.8,
R.sup.10 to R.sup.14, R.sup.18 to R.sup.21, X.sup.31, X.sup.33,
X.sup.34 and X.sup.36 to X.sup.40 are not bound to each other to
form a ring).
[0026] [8] It is preferable in the organic electroluminescent
element according to any one of [1] to [7] that, in the General
Formulae (1) to (7), R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 each
independently represent a hydrogen atom (including a deuterium
atom), an alkyl group, an aryl group, a heteroaryl group, a silyl
group, an alkoxy group, an alkylthio group, an aryloxy group, an
arylthio group, a halogen atom or a cyano group (these may have
further substituents).
[0027] [9] It is preferable in the organic electroluminescent
element according to any one of [1] to [8] that the light emitting
layer include an anthracene-based host material.
[0028] [10] It is preferable in the organic electroluminescent
element according to any one of [1] to [9] that the light emitting
layer be formed by a vacuum deposition process.
[0029] [11] It is preferable in the organic electroluminescent
element according to any one of [1] to [9] that the light emitting
layer be formed by a wet process.
[0030] [12] A light emitting device using the organic
electroluminescent element according to any one of [1] to [11].
[0031] [13] A display device using the organic electroluminescent
element according to any one of [1] to [11].
[0032] [14] An illumination device using the organic
electroluminescent element according to any one of [1] to [11].
[0033] [15] A compound represented by following General Formula
(1),
##STR00010##
(wherein, in General Formula (1), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represent a hydrogen atom (including a
deuterium atom) or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5, R.sup.9 and
R.sup.10 each independently represent a hydrogen atom or a
substituent, L.sup.- represents a divalent linking group, DG.sup.1
represents an electron donating group, and n1 represents 1 or 2,
however, R.sup.1 to R.sup.3, R.sup.5 to R.sup.10, L.sup.1, and
DG.sup.1 are not bound to each other to form a ring).
[0034] [16] It is preferable in the compound according to [15]
that, in the General Formula (1), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represent a hydrogen atom (including a
deuterium atom), an alkyl group, an aryl group, a heteroaryl group,
a silyl group, an alkoxy group, an alkylthio group, an aryloxy
group, an arylthio group, a halogen atom or a cyano group (these
may have further substituents).
[0035] The organic electroluminescent element of the present
invention has sufficient luminous efficiency and excellent
chromaticity. The organic electroluminescent element having
sufficient luminous efficiency and excellent chromaticity can
easily be produced by using compounds of the present invention as
light emitting material of a light emitting layer. Another
advantage is that the light emitting device, the display device,
and the illumination device of the present invention have small
power consumption, and excellent chromaticity.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 is a schematic view showing one example of a
configuration of an organic electroluminescent element according to
the present invention.
[0037] FIG. 2 is a schematic view showing one example of a light
emitting device according to the present invention.
[0038] FIG. 3 is a schematic view showing one example of an
illumination device according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0039] Hereinbelow, the details of the present invention will be
described. The description of the configuration requirements below
is based on representative embodiments and specific examples of the
present invention, but the present invention is not limited to
these embodiments and specific examples. Incidentally, in the
present specification, the range expressed with "to" means a range
including the numerical values before and after "to" as the lower
limit and the upper limit, respectively.
[0040] In the present invention, the hydrogen atom in the
description of each general formula also includes isotopes (a
deuterium atom and the like), and the atoms constituting the
substituent are also intended to include isotopes of the atoms,
unless specifically distinguished.
Organic Electroluminescent Element, and Compounds]
[0041] The compounds of the present invention are represented by
the general formula (1) below.
[0042] The organic electroluminescent element of the present
invention includes a substrate, a pair of electrodes disposed on
the substrate and that includes an anode and a cathode, and an
organic layer disposed between the electrodes, wherein the organic
layer contains a compound represented by the following general
formula (1).
##STR00011##
(In the general formula (1), R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 each independently represent a hydrogen atom (including a
deuterium atom) or a substituent with a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5, R.sup.9,
and R.sup.10 each independently represent a hydrogen atom or a
substituent, L.sup.1 represents a bivalent linking group, and
DG.sup.1 represents a donor group. n1 represents 1 or 2. However,
R.sup.1 to R.sup.3, R.sup.5 to R.sup.10, L.sup.1, and DG.sup.1 are
not bound to each other to form a ring.)
[0043] The following specifically describes the structures of the
compounds of general formula (1) used as light emitting material
for the organic electroluminescent element of the present
invention, and other configurations of the organic
electroluminescent element of the present invention.
Compounds of General Formula (1)
[0044] In the present invention, the hydrogen atom in the
description of the general formula (1) also includes isotopes (a
deuterium atom and the like), and the atoms constituting the
substituent are also intended to include isotopes of the atoms.
[0045] In the general formula (1), R.sup.5, R.sup.9, and R.sup.10
each independently represent a hydrogen atom or a substituent.
Examples of the substituents represented by R.sup.5, R.sup.9, and
R.sup.10 in the general formula (1) include substituents having a
second donor group represented by -(L.sup.2).sub.n2-DG.sup.2 (where
L.sup.2 represents a bivalent linking group, DG.sup.2 represents a
donor group, and n2 represents 1 or 2), and the Substituent Group A
below.
Substituent Group A
[0046] An alkyl group (preferably having 1 to 30 carbon atoms, more
preferably having 1 to 20 carbon atoms, and particularly preferably
having 1 to 10 carbon atoms, for example, methyl, ethyl, isopropyl,
t-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl,
and cyclohexyl), an alkenyl group (preferably having 2 to 30 carbon
atoms, more preferably 2 to 20 carbon atoms, and particularly
preferably 2 to 10 carbon atoms, for example, vinyl, allyl,
2-butenyl and 3-pentenyl), an alkynyl group (preferably having 2 to
30 carbon atoms, more preferably 2 to 20 carbon atoms, and
particularly preferably 2 to 10 carbon atoms, for example,
propargyl and 3-pentynyl), an aryl group (preferably having 6 to 30
carbon atoms, more preferably having 6 to 20 carbon atoms, and
particularly preferably having 6 to 12 carbon atoms, for example,
phenyl, p-methylphenyl, naphthyl, and anthranyl), an amino group
(preferably has 0 to 30 carbon atoms, more preferably 0 to 20
carbon atoms, and particularly preferably 0 to 10 carbon atoms, for
example, amino, methylamino, dimethylamino, diethylamino,
dibenzylamino, diphenylamino, and ditolylamino), an alkoxy group
(preferably having 1 to 30 carbon atoms, more preferably having 1
to 20 carbon atoms, and particularly preferably having 1 to 10
carbon atoms, for example, methoxy, ethoxy, butoxy, and
2-ethylhexyloxy), an aryloxy group (preferably having 6 to 30
carbon atoms, more preferably having 6 to 20 carbon atoms, and
particularly preferably having 6 to 12 carbon atoms, for example,
phenyloxy, 1-naphthyloxy and 2-naphthyloxy), a heterocyclic oxy
group (preferably having 1 to 30 carbon atoms, more preferably 1 to
20 carbon atoms, and particularly preferably 1 to 12 carbon atoms,
for example, pyridyloxy, pyrazyloxy, pyrimidyloxy and quinolyloxy),
an acyl group (preferably having 2 to 30 carbon atoms, more
preferably 2 to 20 carbon atoms, and particularly preferably 2 to
12 carbon atoms, for example, acetyl, benzoyl, formyl and
pivaloyl), an alkoxycarbonyl group (preferably having 2 to 30
carbon atoms, more preferably 2 to 20 carbon atoms, and
particularly preferably 2 to 12 carbon atoms, for example,
methoxycarbonyl and ethoxycarbonyl), an aryloxycarbonyl group
(preferably having 7 to 30 carbon atoms, more preferably 7 to 20
carbon atoms, and particularly preferably 7 to 12 carbon atoms, for
example, phenyloxycarbonyl), an acyloxy group (preferably having 2
to 30 carbon atoms, more preferably 2 to 20 carbon atoms, and
particularly preferably 2 to 10 carbon atoms, for example, acetoxy
and benzoyloxy), an acylamino group (preferably having 2 to 30
carbon atoms, more preferably 2 to 20 carbon atoms, and
particularly preferably 2 to 10 carbon atoms, for example,
acetylamino and benzoylamino), an alkoxycalbonylamino group
(preferably having 2 to 30 carbon atoms, more preferably 2 to 20
carbon atoms, and particularly preferably 2 to 12 carbon atoms, for
example, methoxycalbonylamino), an aryloxycarbonylamino group
(preferably having 7 to 30 carbon atoms, more preferably 7 to 20
carbon atoms, and particularly preferably 7 to 12 carbon atoms, for
example, phenyloxycarbonylamino), a sulfonylamino group (preferably
having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms,
and particularly preferably 1 to 12 carbon atoms, for example,
methanesulfonylamino and benzenesulfonylamino), a sulfamoyl group
(preferably having 0 to 30 carbon atoms, more preferably 0 to 20
carbon atoms, and particularly preferably 0 to 12 carbon atoms, for
example, sulfamoyl, methyl sulfamoyl, dimethyl sulfamoyl and phenyl
sulfamoyl), a carbamoyl group (preferably having 1 to 30 carbon
atoms, more preferably 1 to 20 carbon atoms, and particularly
preferably 1 to 12 carbon atoms, for example, carbamoyl, methyl
carbamoyl, diethyl carbamoyl and phenyl carbamoyl), an alkylthio
group (preferably having 1 to 30 carbon atoms, more preferably
having 1 to 20 carbon atoms, and particularly preferably having 1
to 12 carbon atoms, for example, methylthio and ethylthio), an
arylthio group (preferably having 6 to 30 carbon atoms, more
preferably having 6 to 20 carbon atoms, and particularly preferably
having 6 to 12 carbon atoms, for example, phenylthio), a
heterocyclic thio group (preferably having 1 to 30 carbon atoms,
more preferably having 1 to 20 carbon atoms, and particularly
preferably having 1 to 12 carbon atoms, for example, pyridylthio,
2-benzimizolylthio, 2-benzoxazolylthio, and 2-benzthiazolylthio), a
sulfonyl group (preferably having 1 to 30 carbon atoms, more
preferably 1 to 20 carbon atoms, and particularly preferably 1 to
12 carbon atoms, for example, mesyl and tosyl), a sulfinyl group
(preferably having 1 to 30 carbon atoms, more preferably 1 to 20
carbon atoms, and particularly preferably 1 to 12 carbon atoms, for
example, methane sulfinyl and benzene sulfinyl), a ureido group
(preferably having 1 to 30 carbon atoms, more preferably 1 to 20
carbon atoms, and particularly preferably 1 to 12 carbon atoms, for
example, ureido, methylureido and phenylureido), a phosphoramide
group (preferably having 1 to 30 carbon atoms, more preferably 1 to
20 carbon atoms, and particularly preferably 1 to 12 carbon atoms,
for example, diethylphosphoramide and phenyl phosphoramide), a
hydroxy group, a mercapto group, a fluorine atom, a cyano group, a
sulfo group, a carboxyl group, a nitro group, a hydroxamic group, a
sulfino group, a hydrazino group, an imino group, a heterocyclic
group (including an aromatic heterocyclic group, and preferably
having 1 to 30 carbon atoms, and more preferably having 1 to 12
carbon atoms, and examples of the hetero atom include a nitrogen
atom, an oxygen atom, a sulfur atom, a phosphorus atom, a silicon
atom, a selenium atom, or a tellurium atom, specifically pyridyl,
pyrazinyl, pyrimidyl, pyridazinyl, pyrrolyl, pyrazolyl, triazolyl,
imidazolyl, oxazolyl, triazolyl, isoxazolyl, isothiazolyl,
quinolyl, furyl, thienyl, selenophenyl, tellurophenyl, piperidyl,
piperidino, morpholino, pyrrolidyl, pyrrolidino, benzoxazolyl,
benzimidazolyl, benzothiazolyl, a carbazolyl group, an azepinyl
group, and a silolyl group), a silyl group (preferably has 3 to 40
carbon atoms, more preferably 3 to 30, and particularly preferably
having 3 to 24 carbon atoms, for example, trimethylsilyl, and
triphenylsilyl), a silyloxy group (preferably having 3 to 40 carbon
atoms, more preferably 3 to 30 carbon atoms, and particularly
preferably 3 to 24 carbon atoms, for example, trimethylsilyloxy and
triphenylsilyloxy), a phosphoryl group (for example,
diphenylphosphoryl group and dimethylphosphoryl group).
[0047] These substituents may be further substituted, and examples
of the further substituents include the groups selected from the
Substituent Group A as described above. Further, the substituent
substituted with the substituent may be further substituted, and
examples of the further substituents include the groups selected
from the Substituent Group A as described above. Further, the
substituent substituted with the substituent that has been
substituted with the substituent may be further substituted, and
examples of the further substituents include the groups selected
from the Substituent Group A as described above.
[0048] Preferably, R.sup.5, R.sup.9, and R.sup.10 each
independently represent a hydrogen atom, an alkyl group, an aryl
group, a heteroaryl group, --NY.sup.1Y.sup.2, --OY.sup.3,
--SY.sup.4 (where Y.sup.1 to Y.sup.4 each independently represent
an alkyl group, an aryl group, or a heteroaryl group, and these may
further have a substituent), a halogen atom, a silyl group, or a
substituent that includes a second donor group represented by
-(L.sup.2).sub.n2-DG.sup.2.
[0049] More preferably, R.sup.5, R.sup.9, and R.sup.10 include at
least one -(L.sup.2).sub.n2-DG.sup.2, even more preferably only one
-(L.sup.2).sub.n2-DG.sup.2. Note that the preferred ranges of
L.sup.2, n2, and DG.sup.2 are the same as the preferred ranges of
L.sup.1, n1, and DG.sup.1, respectively, and will be described
later.
[0050] The positions of -(L.sup.2).sub.n2-DG.sup.2 included in
R.sup.5, R.sup.9, and R.sup.10 are not particularly limited.
However, it is preferable that R.sup.9 is
-(L.sup.2).sub.n2-DG.sup.2 from the viewpoint of blue color purity
(chromaticity) and luminous efficiency.
[0051] Specifically, it is particularly preferable that R.sup.5 and
R.sup.10 are hydrogen atoms.
[0052] In the general formula (1), R.sup.1 to R.sup.3 and R.sup.6
to R.sup.8 each independently represent a hydrogen atom (including
a deuterium atom) or a substituent having a Hammett substituent
constant .sigma..sub.p value of -0.15 or more. Having such
substituents are preferable from the viewpoint of improving the
blue color purity of the organic electroluminescent element. Note
that the emission of the organic electroluminescent element
approaches light blue in color when, for example, compounds having
a diphenylamino group (.sigma..sub.p value of -0.22) not satisfying
the foregoing ranges are used for R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8.
[0053] The Hammett equation, proposed in 1935 by L. P. Hammett,
describes empirical rules to quantitatively discuss the effects of
substituents on the reactions or equilibriums of benzene
derivatives. The validity of this equation is now widely
recognized. The substituent constants required of the Hammett
equation include .sigma..sub.p value and .sigma..sub.m value, and
these can be found in many books. For example, detailed
explanations can be found in books such as The Hammett Equation,
-Structure and Reactivity-, Naoki Inamoto (Maruzen), Shin Jikken
Kagaku Kouza 14, Synthesis and Reaction of Organic Compounds V, Ed.
The Chemical Society of Japan, p. 2605 (Maruzen), Riron Yuuki
Kagaku Kaisetsu, p. 217, Tadao Nakatani (Tokyo Kagaku Dojin), and
Chemical Review, Vol. 91, pp. 165 to 195 (1991).
[0054] Preferably, R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 each
independently represent a hydrogen atom (including a deuterium
atom) or a substituent having a Hammett substituent constant
.sigma..sub.p value of -0.15 to 0.8, more preferably a hydrogen
atom (including a deuterium atom) or a substituent having a Hammett
substituent constant .sigma..sub.p value of -0.15 to 0.3.
[0055] It is preferable in the organic electroluminescent element
of the present invention that, in the general formula (1), R.sup.1
to R.sup.3 and R.sup.6 to R.sup.8 each independently represent a
hydrogen atom (including a deuterium atom), an alkyl group, an aryl
group, a heteroaryl group, a silyl group, an alkoxy group, an
alkylthio group, an aryloxy group, an arylthio group, a halogen
atom, or a cyano group (these may have further substituents).
[0056] From the viewpoint of inhibition of association, R.sup.1 to
R.sup.3 and R.sup.6 to R.sup.8 preferably each independently
represent a hydrogen atom (including a deuterium atom), an alkyl
group, an aryl group, a silyl group, or an aryloxy group,
particularly preferably a hydrogen atom (including a deuterium
atom), or an alkyl group.
[0057] The preferred range of each substituent represented by
R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 is the same as the
preferred range of each substituent in the Substituent Group A.
[0058] More preferably, the alkyl groups represented by R.sup.1 to
R.sup.3 and R.sup.6 to R.sup.8 are each independently a methyl
group, an isopropyl group, or a t-butyl group, particularly
preferably a t-butyl group from among the preferred range of each
substituent in the Substituent Group A.
[0059] More preferably, the aryl groups represented by R.sup.1 to
R.sup.3 and R.sup.6 to R.sup.8 are each independently a phenyl
group. The aryl groups represented by R.sup.1 to R.sup.3 and
R.sup.6 to R.sup.8 may be substituted with substituents such as
those in the Substituent Group A, and are preferably substituted.
Examples of the aryl groups represented by R.sup.1 to R.sup.3 and
R.sup.6 to R.sup.8 may be those substituted with an alkyl group, an
aryl group, a heteroaryl group, an amino group, a fluorine atom, or
a silyl group. Those substituted with an alkyl group are preferred.
The alkyl group is preferably a methyl group, an isopropyl group,
or a t-butyl group, more preferably a methyl group. When the aryl
groups represented by R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8
have substituents, the number of substituents is preferably 1 to 3,
more preferably 2.
[0060] It is particularly preferable that the silyl groups
represented by R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 are each
independently a trimethylsilyl group from among the preferred range
of each substituent in the Substituent Group A.
[0061] It is particularly preferable that the aryloxy groups
represented by R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 are each
independently a phenoxy group from among the preferred range of
each substituent in the Substituent Group A.
[0062] Preferably, the number of substituents having a Hammett
substituent constant .sigma..sub.p value or -0.15 or more in
R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 in the general formula
(1) is 0 to 4, more preferably 0 to 2, particularly preferably 0 or
2, even more preferably 0.
[0063] When R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 in the
general formula (1) have substituents having a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, the positions of the
substituents are not particularly limited. However, it is
preferable to have the substituents in at least one of R.sup.2 and
R.sup.7, more preferably in both of R.sup.2 and R.sup.7 from the
viewpoint of inhibition of association, and durability.
[0064] In the general formula (1), L.sup.1 represents a bivalent
linking group. Examples of L.sup.1 include an arylene group, a
heteroarylene group, an alkenylene group, and an alkynylene
group.
[0065] In the organic electroluminescent element of the present
invention, L.sup.1 preferably represents an arylene group or a
heteroarylene group, more preferably an arylene group of a 6- to
18-membered ring, or a heteroarylene group of a 5- to 20-membered
ring, particularly preferably an arylene group of a 6- to
12-membered ring, or a heteroarylene group of a 5- to 16-membered
ring, particularly preferably an arylene group of 6 to 10 carbon
atoms, or a heteroarylene group of a 5- to 10-membered ring, even
more preferably a phenylene group, or a heteroarylene group of a
6-membered ring.
[0066] L.sup.1 may be substituted with substituents other than
DG.sup.1, provided that such substitution does not depart from the
gist of the present invention. In this case, the substituents are
not particularly limited, and are preferably substituents having a
Hammett substituent constant .sigma..sub.p value of less than 0.1,
further preferably substituents having a .sigma..sub.p value of
-0.6 to 0. Particularly, when L.sup.1 represents an arylene group
or a heteroarylene group, it is preferable that the only
substituents of the arylene group or the heteroarylene group
represented by L.sup.1 are substituents having a Hammett
substituent constant .sigma..sub.p value of less than 0.1.
[0067] Preferably, the substituents having a Hammett substituent
constant .sigma..sub.p value of less than 0.1 as the substituents
of L.sup.1 other than DG.sup.1 are fluorine atoms (.sigma..sub.p
value of 0.06), alkyl groups, silyl groups, aryl groups, heteroaryl
groups, --NY.sup.31Y.sup.32, --OY.sup.33, or --SY.sup.34 (where
Y.sup.31 to Y.sup.34 each independently represent an alkyl group,
an aryl group, or a heteroaryl group), more preferably alkyl
groups, aryl groups, or heteroaryl groups. These may have further
substituents. The preferred range of each substituent of L.sup.1
other than DG.sup.1 is the same as the preferred range of each
substituent in the Substituent Group A.
[0068] In the present invention, it is preferable that L.sup.1 in
the general formula (1) does not have substituents other than
DG.sup.1.
[0069] In the general formula (1), n1 represents 1 or 2, and is
preferably 1.
[0070] In the general formula (1), DG.sup.1 represents a donor
group.
[0071] As used herein, the donor group means an electron donating
substituent, and a substituent that shows a negative .sigma..sub.p
value in the Hammett equation.
[0072] In the organic electroluminescent element of the present
invention, the donor group in the general formula (1) is preferably
represented by --NY.sup.1Y.sup.2, --OY.sup.3, or --SY.sup.4 (where
Y.sup.1 to Y.sup.4 each independently represent an alkyl group, an
aryl group, or a heteroaryl group, and these may have further
substituents, and Y.sup.1 and Y.sup.2 may bind to each other to
form a ring), or by the following general formula (A).
##STR00012##
[0073] In the general formula (A), X.sup.A and X.sup.B each
independently represent O, S, or NY.sup.15, R.sup.15 to R.sup.17
each independently represent a hydrogen atom, an alkyl group, a
silyl group, an aryl group, a heteroaryl group,
--NY.sup.11Y.sup.12, --OY.sup.13, or --SY.sup.14 (where Y.sup.11 to
Y.sup.15 each independently represent an alkyl group, an aryl
group, or a heteroaryl group). These may have further
substituents.
[0074] X.sup.A and X.sup.B each independently represent O, S, or
NY.sup.15, and Y.sup.15 each independently represent an alkyl
group, an aryl group, or a heteroaryl group. These may have further
substituents. Examples of the further substituents include those in
the Substituent Group A in the case of substituents on carbon
atoms, and those in the Substituent Group B below in the case of
substituents on nitrogen atoms.
[0075] X.sup.A and X.sup.B are preferably O or S, more preferably
S.
Substituent Group B
[0076] An alkyl groups (preferably having 1 to 30 carbon atoms,
more preferably having 1 to 20 carbon atoms, and particularly
preferably having 1 to 10 carbon atoms, for example, methyl, ethyl,
isopropyl, t-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopropyl,
cyclopentyl, cyclohexyl), an alkenyl group (preferably having 2 to
30 carbon atoms, more preferably 2 to 20 carbon atoms, and
particularly preferably 2 to 10 carbon atoms, for example, vinyl,
allyl, 2-butenyl, and 3-pentenyl), an alkynyl group (preferably
having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms,
and particularly preferably 2 to 10 carbon atoms, for example,
propargyl and 3-pentynyl), an aryl group (preferably having 6 to 30
carbon atoms, more preferably having 6 to 20 carbon atoms, and
particularly preferably having 6 to 12 carbon atoms, for example,
phenyl, p-methylphenyl, naphthyl, and anthranyl), a cyano group,
and a heterocyclic group (including an aromatic heterocyclic group,
and preferably having 1 to 30 carbon atoms, and more preferably
having 1 to 12 carbon atoms, and examples of the hetero atom
include a nitrogen atom, an oxygen atom, a sulfur atom, a
phosphorus atom, a silicon atom, a selenium atom, and a tellurium
atom, specifically pyridyl, pyrazinyl, pyrimidyl, pyridazinyl,
pyrrolyl, pyrazolyl, triazolyl, imidazolyl, oxazolyl, triazolyl,
isoxazolyl, isothiazolyl, quinolyl, furyl, thienyl, selenophenyl,
tellurophenyl, piperidyl, piperidino, morpholino, pyrrolidyl,
pyrrolidino, benzoxazolyl, benzimidazolyl, benzothiazolyl, a
carbazolyl group, an azepinyl group, and a silolyl group).
[0077] These substituents may be further substituted, and examples
of the further substituents include the groups selected from the
Substituent Group B as described above. Further, the substituent
substituted with the substituent may be further substituted, and
examples of the further substituents include the groups selected
from the Substituent Group B as described above. Further, the
substituent substituted with the substituent that has been
substituted with the substituent may be further substituted, and
examples of the further substituents include the groups selected
from the Substituent Group B as described above.
[0078] R.sup.15 to R.sup.18 each independently represent a hydrogen
atom, an alkyl group, a silyl group, an aryl group, a heteroaryl
group, --NY.sup.11Y.sup.12, --OY.sup.13, or --SY.sup.14, and
Y.sup.11 to Y.sup.14 each independently represent an alkyl group,
an aryl group, or a heteroaryl group. These may have further
substituents. R.sup.15 to R.sup.18 are preferably hydrogen atoms,
alkyl groups, aryl groups, or --NY.sup.1lY.sup.12, more preferably
alkyl groups, or --NY.sup.11Y.sup.12.
[0079] Examples of the further substituents include those in the
Substituent Group A in the case of substituents on carbon atoms,
and those in the Substituent Group B in the case of substituents on
nitrogen atoms. Having an alkyl group, a silyl group, an aryl
group, or a heteroaryl group is preferred from the viewpoint of
inhibition of association.
[0080] The donor group in the general formula (1) is preferably
--NY.sup.1Y.sup.2, --OY.sup.3, or a group represented by the
general formula (A), more preferably --NY.sup.1Y.sup.2. It is
further preferable, from the viewpoint of inhibition of
association, that the donor group has an alkyl group, a silyl
group, an aryl group, or a heteroaryl group.
[0081] As mentioned above, Y.sup.1 to Y.sup.4 in --NY.sup.1Y.sup.2,
--OY.sup.3, and --SY.sup.4 each independently represent an alkyl
group, an aryl group, or a heteroaryl group, and are preferably
aryl groups.
[0082] The preferred range of each substituent represented by
Y.sup.1 to Y.sup.4 is the same as the preferred range of each
substituent in the Substituent Group A. Of these, Y.sup.1 and
Y.sup.2 in --NY.sup.1Y.sup.2 preferably each independently
represent a phenyl group, a naphthyl group, or a phenanthryl group,
more preferably a phenyl group, or a naphthyl group, particularly
preferably a phenyl group, or a 2-naphthyl group.
[0083] Y.sup.1 and Y.sup.2 in --NY.sup.1Y.sup.2 further may have a
substituent. Example of the further substituents include those in
the Substituent Group A in the case of substituents on carbon
atoms, and those in the Substituent Group B in the case of
substituents on nitrogen atoms. Having a deuterium atom, an alkyl
group, a fluorine atom, a silyl group, an aryl group, or a
heteroaryl group is preferable from the viewpoint of durability and
inhibition of association. It is more preferable to include a
deuterium atom, a methyl group, an isopropyl group, a t-butyl
group, a fluorine atom, a phenyl group (--C.sub.6H.sub.5,
--C.sub.6D.sub.5), a p-methylphenyl group (tolyl group), a
p-isopropylphenyl group, a m-methylphenyl group, an o-methylphenyl
group, a trimethylsilyl group, or a cyano group, more preferably a
deuterium atom, a methyl group, an isopropyl group, a t-butyl
group, a fluorine atom, a phenyl group (--C.sub.6H.sub.5,
--C.sub.6D.sub.5), a p-methylphenyl group (tolyl group), a
m-methylphenyl group, or an o-methylphenyl group, particularly
preferably a methyl group. When Y.sup.1 and Y.sup.2 have further
substituents, the number of further substituents is preferably 1 to
3, more preferably 1 or 2, particularly preferably 1 for Y.sup.1
and Y.sup.2.
[0084] In the general formula (1), R.sup.1 to R.sup.3, R.sup.5 to
R.sup.10, L.sup.1, and DG.sup.1 are not bound to each other to form
a ring. Specifically, the compounds of the present invention have
improved heat resistance, because L.sup.1 and DG.sup.1 do not bind
to any of R.sup.1 to R.sup.3 and R.sup.5 to R.sup.10 to form a
ring.
[0085] In the present invention, the compounds represented by the
general formula (1) are preferably compounds represented by the
following general formula (2).
##STR00013##
[0086] In the general formula (2), R.sup.1 to R.sup.3 and R.sup.6
to R.sup.8 each independently represent a hydrogen atom (including
a deuterium atom) or a substituent having a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
L.sup.1 and L.sup.2 each independently represent a bivalent linking
group, and DG.sup.1 and DG.sup.2 each independently represent a
donor group. n1 and n2 each independently represent 1 or 2.
However, R.sup.1 to R.sup.3, R.sup.5 to R.sup.8, R.sup.10, L.sup.1,
L.sup.2, DG.sup.1 and DG.sup.2 are not bound to each other to form
a ring.
[0087] The preferred ranges of R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 in the general formula (2) are the same as the preferred
ranges of R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 in the general
formula (1).
[0088] The preferred ranges of R.sup.5 and R.sup.10 in the general
formula (2) are the same as the preferred ranges of R.sup.5 and
R.sup.10 in the general formula (1).
[0089] The preferred ranges of L.sup.1 and L.sup.2 in the general
formula (2) are the same as the preferred ranges of L.sup.1 and
L.sup.2 in the general formula (1).
[0090] The preferred ranges of DG.sup.1 and DG.sup.2 in the general
formula (2) are the same as the preferred ranges of DG.sup.1 and
DG.sup.2 in the general formula (1).
[0091] The preferred ranges of n1 and n2 in the general formula (2)
are the same as the preferred ranges of n1 and n2 in the general
formula (1).
[0092] In the present invention, the compounds represented by the
general formula (2) are preferably compounds represented by the
following general formula (3).
##STR00014##
[0093] In the general formula (3), R.sup.1 to R.sup.3 and R.sup.6
to R.sup.8 each independently represent a hydrogen atom (including
a deuterium atom) or a substituent having a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
L.sup.1 and L.sup.2 each independently represent a bivalent linking
group, R.sup.11 to R.sup.14 each independently represent an alkyl
group, an aryl group, or a heteroaryl group. n1 and n2 each
independently represent 1 or 2. However, R.sup.1 to R.sup.3,
R.sup.5 to R.sup.8, R.sup.10 to R.sup.14, L.sup.1 and L.sup.2 are
not bound to each other to form a ring.
[0094] The preferred ranges of R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 in the general formula (3) are the same as the preferred
ranges of R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 in the general
formula (1).
[0095] The preferred ranges of R.sup.5 and R.sup.10 in the general
formula (3) are the same as the preferred ranges of R.sup.5 and
R.sup.10 in the general formula (1).
[0096] The preferred ranges of L.sup.1 and L.sup.2 in the general
formula (3) are the same as the preferred ranges of L.sup.1 and
L.sup.2 in the general formula (1).
[0097] The preferred ranges of n1 and n2 in the general formula (3)
are the same as the preferred ranges of n1 and n2 in the general
formula (1).
[0098] R.sup.11 to R.sup.14 in the general formula (3) each
independently represent an alkyl group, an aryl group, or a
heteroaryl group. The preferred ranges of R.sup.11 and R.sup.12 are
the same as the preferred ranges of Y.sup.1l and Y.sup.12 in the
description of DG.sup.1 in the general formula (1). The preferred
ranges of R.sup.13 and R.sup.14 are the same as the preferred
ranges of Y.sup.11 and Y.sup.12 in the description of DG.sup.1 in
the general formula (1).
[0099] In the present invention, the compounds represented by the
general formula (3) are preferably compounds represented by any one
of the following general formulae (4) to (7).
##STR00015##
[0100] In the general formula (4), R.sup.1 to R.sup.3 and R.sup.6
to R.sup.8 each independently represent a hydrogen atom (including
a deuterium atom) or a substituent having a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
R.sup.11 to R.sup.14 each independently represent an alkyl group,
an aryl group, or a heteroaryl group. A.sup.1 to A.sup.8 each
independently represent CRz (two adjacent CRz's may jointly form a
five- or six-membered ring) or N, and Rz represents a hydrogen atom
or a substituent. However, R.sup.1 to R.sup.3, R.sup.5 to R.sup.8,
R.sup.10 to R.sup.14, and A.sup.1 to A.sup.8 are not bound to each
other to form a ring.
[0101] The preferred ranges of R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 in the general formula (4) are the same as the preferred
ranges of R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 in the general
formula (1).
[0102] The preferred ranges of R.sup.5 and R.sup.10 in the general
formula (4) are the same as the preferred ranges of R.sup.5 and
R.sup.10 in the general formula (1).
[0103] R.sup.11 to R.sup.14 in the general formula (4) each
independently represent an alkyl group, an aryl group, or a
heteroaryl group. The preferred ranges of R.sup.11 and R.sup.12 are
the same as the preferred ranges of Y.sup.11 and Y.sup.12 in the
description of DG.sup.1 in the general formula (1). The preferred
ranges of R.sup.13 and R.sup.14 are the same as the preferred
ranges pf Y.sup.1l and Y.sup.12 in the description of DG.sup.1 in
the general formula (1).
[0104] In the general formula (4), A.sup.1 to A.sup.4 each
independently represent CRz (two adjacent CRz's may jointly form a
five- or six-membered ring) or N, and Rz represents a hydrogen atom
or a substituent. A.sup.1 and A.sup.2 may be fused to form an
aromatic ring. Rz represents a hydrogen atom, an alkyl group, an
aryl group, or a heteroaryl group, and these may have further
substituents. Rz preferably represents a hydrogen atom, an alkyl
group, an aryl group, or a heteroaryl group, and is more preferably
a hydrogen atom. A.sup.1 to A.sup.4 are preferably each
independently CH or N. The number of N atoms in A.sup.1 to A.sup.4
is preferably 0 to 3, more preferably 0 to 2, particularly
preferably 0 or 1, even more preferably 0. Examples of the further
substituents of A.sup.1 to A.sup.4 include those in the Substituent
Group A in the case of substituents on carbon atoms, and those in
the Substituent Group B in the case of substituents on nitrogen
atoms.
[0105] In the general formula (4), A.sup.5 to A.sup.8 each
independently represent CRz (two adjacent CRz's may jointly form a
five- or six-membered ring) or N, and Rz represents a hydrogen atom
or a substituent. The relationships and the preferred ranges of
A.sup.5 to A.sup.8 are the same as the relationships and the
preferred ranges of A.sup.1 to A.sup.4.
##STR00016##
[0106] In the general formula (5), R.sup.1 to R.sup.3 and R.sup.6
to R.sup.8 each independently represent a hydrogen atom (including
a deuterium atom) or a substituent having a Hammett substituent
constant .sigma..sub.p value or -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
R.sup.11 to R.sup.14 each independently represent an alkyl group,
an aryl group, or a heteroaryl group. X.sup.1 to X.sup.6 each
independently represent CRz (two adjacent CRz's may jointly form a
five- or six-membered ring), --N.dbd., NRy, O, or S, and Rz and Ry
each independently represent a hydrogen atom or a substituent.
However, R.sup.1 to R.sup.3, R.sup.5 to R.sup.8, R.sup.10 to
R.sup.14, and X.sup.1 to X.sup.6 are not bound to each other to
form a ring.
[0107] The preferred ranges of R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 in the general formula (5) are the same as the preferred
ranges of R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 in the general
formula (1).
[0108] The preferred ranges of R.sup.5 and R.sup.10 in the general
formula (5) are the same as the preferred ranges of R.sup.5 and
R.sup.10 in the general formula (1).
[0109] R.sup.11 to R.sup.14 in the general formula (5) each
independently represent an alkyl group, an aryl group, or a
heteroaryl group. The preferred ranges of R.sup.11 and R.sup.12 are
the same as the preferred ranges of Y.sup.11 and Y.sup.12 in the
description of DG.sup.1 in the general formula (1). The preferred
ranges of R.sup.13 and R.sup.14 are the same as the preferred
ranges of Y.sup.11 and Y.sup.12 in the description of DG.sup.1 in
the general formula (1).
[0110] In the general formula (5), X.sup.1 to X.sup.6 each
independently represent CRz (two adjacent CRz's may jointly form a
five- or six-membered ring), --N.dbd., NRy, O, or S.
[0111] Rz and Ry each independently represent a hydrogen atom or a
substituent. Examples of the substituent Rz on carbon atoms include
substituents in the Substituent Group A. Examples of the
substituent Ry on nitrogen atoms include substituents in the
Substituent Group B. The preferred range of Rz in the general
formula (5) is the same as the preferred range of Rz in the general
formula (4). The preferred range of Ry in the general formula (5)
includes a hydrogen atom, or is the same as the preferred range of
the Substituent Group B.
[0112] X.sup.1 to X.sup.3 mean linking groups forming the aromatic
ring. For example, X.sup.1 to X.sup.3 are preferably represented by
two atom linking groups each having three bonds, and a single atom
linking group having two bonds in a resonance structure. Here, the
two atom linking groups having three bonds in X.sup.1 to X.sup.3
are CRz or --N.dbd., and the single atom linking group having two
bonds in X.sup.1 to X.sup.3 is NRy, O, or S. The two atom linking
groups having three bonds in X.sup.1 to X.sup.3 are preferably CH,
CAr (Ar is an aryl group), or N, more preferably CH or N,
particularly preferably CH. The single atom linking group having
two bonds in X.sup.1 to X.sup.3 is preferably NR(R is an alkyl
group), NAr (Ar is an aryl group), O, or S, more preferably O or S,
particularly preferably O. Note that the position of the atom
linking group having two bonds in X.sup.1 to X.sup.3 in a resonance
structure is not particularly limited, and is preferably at
X.sup.1.
[0113] The relationships and the preferred ranges of X.sup.4 to
X.sup.5 are the same as the relationships and the preferred ranges
of X.sup.1 to X.sup.3. Note that the position of the atom linking
group having two bonds in X.sup.4 to X.sup.6 in a resonance
structure is not particularly limited, and is preferably at
X.sup.4.
##STR00017##
[0114] In the general formula (6), R.sup.1 to R.sup.3 and R.sup.6
to R.sup.8 each independently represent a hydrogen atom (including
a deuterium atom) or a substituent having a Hammett substituent
constant .sigma..sub.p value of -0.15 or more, R.sup.5 and R.sup.10
each independently represent a hydrogen atom or a substituent,
R.sup.11 to R.sup.14 each independently represent an alkyl group,
an aryl group, or a heteroaryl group. X.sup.11, X.sup.12, X.sup.14,
and X.sup.16 to X.sup.20 each independently represent CRz (two
adjacent CRz's may jointly form a five- or six-membered ring),
--N.dbd., NRy, O, or S, Rz and Ry each independently represent a
hydrogen atom or a substituent. However, R.sup.1 to R.sup.3,
R.sup.5 to R.sup.8, R.sup.10 to R.sup.14, X.sup.11, X.sup.13,
X.sup.14, and X.sup.16 to X.sup.20 are not bound to each other to
form a ring.
[0115] The preferred ranges of R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 in the general formula (6) are the same as the preferred
ranges of R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 in the general
formula (1).
[0116] The preferred ranges of R.sup.5 and R.sup.10 in the general
formula (6) are the same as the preferred ranges of R.sup.5 and
R.sup.10 in the general formula (1).
[0117] R.sup.11 to R.sup.14 in the general formula (6) each
independently represent an alkyl group, an aryl group, or a
heteroaryl group. The preferred ranges of R.sup.11 and R.sup.12 are
the same as the preferred ranges of Y.sup.11 and Y.sup.12 in the
description of DG.sup.1 in the general formula (1). The preferred
ranges of R.sup.12 and R.sup.14 are the same as the preferred
ranges of Y.sup.11 and Y.sup.12 in the description of DG.sup.1 in
the general formula (1).
[0118] In the general formula (6), X.sup.11, X.sup.13, X.sup.14,
and X.sup.16 to X.sup.20 each independently represent CRz (two
adjacent CRz's may jointly form a five- or six-membered ring),
--N.dbd., NRy, O, or S.
[0119] Rz and Ry each independently represent a hydrogen atom or a
substituent. Examples of the substituent Rz on carbon atoms include
substituents in the Substituent Group A. Examples of the
substituent Ry on nitrogen atoms include substituents in the
Substituent Group B. The preferred range of Rz in the general
formula (6) is the same as the preferred range of Rz in the general
formula (4). The preferred range of Ry in the general formula (6)
includes a hydrogen atom, or is the same as the preferred range of
the Substituent Group B.
[0120] X.sup.11 and X.sup.13 means linking groups forming the
aromatic ring. For example, X.sup.11 and X.sup.13 are preferably
represented by a single atom linking group having three bonds, and
a single atom linking group having two bonds in a resonance
structure. Here, the single atom linking group having three bonds
in X.sup.11 and X.sup.13 are CRz or --N.dbd., and the single atom
linking group having two bonds in X.sup.11 and X.sup.13 is NRy, O,
or S. The single atom linking group having three bonds in X.sup.11
and X.sup.13 are preferably CH, CAr (Ar is an aryl group), or N,
more preferably CH or N, particularly preferably CH. The single
atom linking group having two bonds in X.sup.11 and X.sup.13 is
preferably O or S, more preferably S. Note that the position of the
atom linking group having two bonds in X.sup.11 and X.sup.13 in a
resonance structure is not particularly limited, and is preferably
at X.sup.11.
[0121] The relationship and the preferred ranges of X.sup.18 and
X.sup.17 are the same as the relationship and the preferred ranges
of X.sup.11 and X.sup.13. Note that the position of the atom
linking group having two bonds in X.sup.18 and X.sup.17 in a
resonance structure is not particularly limited, and is preferably
at X.sup.18.
[0122] The relationship and the preferred ranges of X.sup.14 and
X.sup.16 are the same as the relationship and the preferred ranges
of X.sup.11 and X.sup.13. Note that the position of the atom
linking group having two bonds in X.sup.14 and X.sup.16 in a
resonance structure is not particularly limited, and is preferably
at X.sup.14.
[0123] The relationship and the preferred ranges of X.sup.19 and
X.sup.20 are the same as the relationship and the preferred ranges
of X.sup.11 and X.sup.13. Note that the position of the atom
linking group having two bonds in X.sup.19 and X.sup.20 in a
resonance structure is not particularly limited, and is preferably
at X.sup.19.
##STR00018##
[0124] In the general formula (7), R.sup.1 to R.sup.3 and R.sup.6
to R.sup.8 each independently represent a hydrogen atom (including
a deuterium atom), or a substituent having a Hammett substituent
constant p value of -0.15 or more, R.sup.5 and R.sup.10 each
independently represent a hydrogen atom or a substituent, R.sup.11
to R.sup.14 each independently represent an alkyl group, an aryl
group, or a heteroaryl group. R.sup.18 to R.sup.21 each
independently represent a hydrogen atom, a fluorine atom, an alkyl
group, a silyl group, an aryl group, a heteroaryl group,
--NY.sup.21Y.sup.22, --OY.sup.23, or --SY.sup.24 (where Y.sup.21 to
Y.sup.24 each independently represent an alkyl group, an aryl
group, or a heteroaryl group). These may have further substituents.
X.sup.31, X.sup.33, X.sup.34, and X.sup.36 to X.sup.40 each
independently represent CRz (two adjacent CRz's may jointly form a
five- or six-membered ring), --N.dbd., NRy, O, or S, Rz and Ry each
independently represent a hydrogen atom or a substituent. However,
R.sup.1 to R.sup.3, R.sup.5 to R.sup.8, R.sup.10 to R.sup.14,
R.sup.18 to R.sup.21, X.sup.31, X.sup.33, X.sup.34, and X.sup.36 to
X.sup.40 are not bound to each other to form a ring.
[0125] The preferred ranges of R.sup.1 to R.sup.3 and R.sup.6 to
R.sup.8 in the general formula (7) are the same as the preferred
ranges of R.sup.1 to R.sup.3 and R.sup.6 to R.sup.8 in the general
formula (1).
[0126] The preferred ranges of R.sup.5 and R.sup.10 in the general
formula (7) are the same as the preferred ranges of R.sup.5 and
R.sup.10 in the general formula (1).
[0127] R.sup.11 to R.sup.14 in the general formula (7) each
independently represent an alkyl group, an aryl group, or a
heteroaryl group. The preferred ranges of R.sup.11 and R.sup.12 are
the same as the preferred ranges of Y.sup.11 and Y.sup.12 in the
description of DG.sup.1 in the general formula (1). The preferred
ranges of R.sup.13 and R.sup.14 are the same as the preferred
ranges of Y.sup.11 and Y.sup.12 in the description of DG.sup.1 in
the general formula (1).
[0128] In the general formula (7), X.sup.31, X.sup.33, X.sup.34,
and X.sup.36 to X.sup.40 each independently represent CRz (two
adjacent CRz's may jointly form a five- or six-membered ring),
--N.dbd., NRy, O, or S.
[0129] Rz and Ry each independently represent a hydrogen atom or a
substituent. Examples of the substituent Rz on carbon atoms include
substituents in the Substituent Group A. Examples of the
substituent Ry on nitrogen atoms include substituents in the
Substituent Group B. The preferred range of Rz in the general
formula (7) is the same as the preferred range of Rz in the general
formula (4). The preferred range of Ry in the general formula (7)
includes a hydrogen atom, or is the same as the preferred range of
the Substituent Group B.
[0130] X.sup.31 and X.sup.33 means linking groups forming the
aromatic ring. For example, X.sup.31 and X.sup.33 are preferably
represented by a single atom linking group having three bonds, and
a single atom linking group having two bonds in a resonance
structure. Here, the single atom linking group having three bonds
in X.sup.31 and X.sup.33 are CRz or --N.dbd., and the single atom
linking group having two bonds in X.sup.31 and X.sup.33 is NRy, O,
or S. The single atom linking group having three bonds in X.sup.31
and X.sup.33 are preferably CH, CAr (Ar is an aryl group), or N,
more preferably CH or N, particularly preferably CH. The single
atom linking group having two bonds in X.sup.31 and X.sup.33 is
preferably O or S, more preferably S. Note that the position of the
atom linking group having two bonds in X.sup.31 and X.sup.33 in a
resonance structure is not particularly limited, and is preferably
at X.sup.31.
[0131] The relationship and the preferred ranges of X.sup.38 and
X.sup.37 are the same as the relationship and the preferred ranges
of X.sup.31 and X.sup.33. Note that the position of the atom
linking group having two bonds in X.sup.38 and X.sup.37 in a
resonance structure is not particularly limited, and is preferably
at X.sup.38.
[0132] The relationship and the preferred ranges of X.sup.34 and
X.sup.36 are the same as the relationship and the preferred ranges
of X.sup.31 and X.sup.33. Note that the position of the atom
linking group having two bonds in X.sup.34 and X.sup.36 in a
resonance structure is not particularly limited, and is preferably
at X.sup.34.
[0133] The relationship and the preferred ranges of X.sup.39 and
X.sup.40 are the same as the relationship and the preferred ranges
of X.sup.31 and X.sup.33. Note that the position of the atom
linking group having two bonds in X.sup.39 and X.sup.40 in a
resonance structure is not particularly limited, and is preferably
at X.sup.39.
[0134] R.sup.18 and R.sup.19 each independently represent a
hydrogen atom, a fluorine atom, an alkyl group, a silyl group, an
aryl group, a heteroaryl group, --NY.sup.21Y.sup.22, --OY.sup.23,
--SY.sup.24 (where Y.sup.21 to Y.sup.24 each independently
represent an alkyl group, an aryl group, or a heteroaryl group).
These may have further substituents. R.sup.18 and R.sup.19 each
independently represent preferably a hydrogen atom, a fluorine
atom, an alkyl group, an aryl group, or --NY.sup.21Y.sup.22, more
preferably a hydrogen atom, a fluorine atom, an alkyl group, or an
aryl group. The preferred range of each substituent represented by
Y.sup.21 to Y.sup.24 is the same as the preferred range of each
substituent in the Substituent Group A.
[0135] Examples of the further substituents of R.sup.18 and
R.sup.19 include those in the Substituent Group A in the case of
the substituents on carbon atoms, and those in the Substituent
Group B in the case of the substituents on nitrogen atoms. However,
R.sup.18 and R.sup.19 are preferably substituents having a Hammett
substituent constant .sigma..sub.p value of 0.1 or less, and more
preferably include a substituent having a .sigma..sub.p value of
-0.5 to 0.1.
[0136] The preferred ranges of R.sup.20 and R.sup.21 are the same
as the preferred ranges of R.sup.18 and R.sup.19.
[0137] The compounds represented by the general formula (1) are
preferably linking groups represented by the general formula (4) or
(5) from among the compounds represented by the general formulae
(4) to (7) from the viewpoint of sufficiently obtaining the effect
of the donor group connected to the pyrene skeleton via L.sup.1 (or
L.sup.2), more preferably linking groups represented by the general
formula (4).
[0138] The maximum luminous wavelength of the organic
electroluminescent element using the compounds represented by the
general formula (1) typically ranges from 400 nm to 480 nm,
preferably 420 nm to 470 nm, further preferably 430 nm to 460 nm.
In the present invention, it is preferable to use particularly the
compounds represented by the general formulae (4) to (7) as the
compounds represented by the general formula (1), because it makes
the maximum luminous wavelength of the organic electroluminescent
element from about 430 nm to 460 nm, and provides blue emission of
particularly high color purity. The maximum luminous wavelength of
the organic electroluminescent element using the compounds
represented by the general formula (1) is most preferably 440 nm or
more and less than 455 nm from the viewpoint of obtaining blue
emission having high color purity.
[0139] The compound represented by the general formula (1)
preferably has a molecular weight of 1,000 or less, more preferably
900 or less, even more preferably 850 or less. By lowering the
molecular weight, the sublimation temperature can be lowered, and
therefore, the thermal decomposition of the compound at a time of
deposition can be prevented. Further, by shortening the deposition
time, energy required for deposition can be suppressed.
[0140] Specific examples of the compounds represented by the
general formula (1) are shown below. However, the compounds of the
general formula (1) that can be used in the present invention
should not be construed to be limited to the specific examples.
##STR00019## ##STR00020## ##STR00021## ##STR00022## ##STR00023##
##STR00024## ##STR00025## ##STR00026## ##STR00027## ##STR00028##
##STR00029##
[0141] The compounds represented by the general formula (1) can be
synthesized by combining known reactions, specifically by using the
methods described in US2010/0244665 and KR10/2011/0057008. The
following describes representative examples of specific synthesis
procedures for the compounds represented by the general formula
(1).
##STR00030## ##STR00031##
[0142] Each step can be performed by using the synthesis methods
and the reaction conditions described in US2010/0244665 and
KR10/2011/0057008.
[0143] After the synthesis, purification is preferably carried out
by column chromatography, recrystallization, or the like, and then
by sublimation purification. By the sublimation purification,
organic impurities can be separated and inorganic salts, residual
solvents, or the like can be removed effectively.
[0144] When the compounds represented by the general formula (1)
are used as light emitting material, the light emitting material in
the thin-film state preferably has a maximum luminous wavelength of
less than 460 nm, more preferably 400 nm or more and less than 460
nm, particularly preferably 420 nm or more and less than 455 nm,
still more preferably 430 nm or more and less than 455 nm, and most
preferably 440 nm or more and less than 455 nm from the viewpoint
of obtaining blue emission of high color purity.
Organic Electroluminescent Element
[0145] The organic electroluminescent element of the present
invention includes a substrate, a pair of electrodes disposed on
the substrate and that includes an anode and a cathode, and an
organic layer disposed between the electrodes, wherein the organic
layer contains a compound represented by the general formula
(1).
[0146] The configuration of the organic electroluminescent element
of the present invention is not particularly limited. FIG. 1 shows
one example of the configuration of the organic electroluminescent
element of the present invention. The organic electroluminescent
element 10 of FIG. 1 has an organic layer between a pair of
electrodes (an anode 3 and a cathode 9) on a substrate 2.
[0147] The element configuration of the organic electroluminescent
element, the substrate, the cathode, and the anode are described in
detail in, for example, JP-A-2008-270736, and the detailed
description thereon in the publication can be applied to the
present invention.
[0148] Hereinbelow, preferred embodiments of the organic
electroluminescent element of the present invention will be
described in detail in the order of the substrate, the electrodes,
the organic layer, the protective layer, the sealing enclosure, a
driving method, a light emitting wavelength, and applications.
Substrate
[0149] The organic electroluminescent element of the present
invention has a substrate.
[0150] The substrate used in the present invention is preferably a
substrate that does not scatter or diminish light starting from the
organic layer. In the case of the organic material, those having
excellent heat resistance, dimensional stability, solvent
resistance, electricity insulating properties, and processibility
are preferred.
Electrodes
[0151] The organic electroluminescent element of the present
invention has a pair of electrodes including an anode and a
cathode, disposed on the substrate.
[0152] In terms of the properties of the light emitting element, at
least one electrode of a pair of electrodes, the anode and the
cathode, is preferably transparent or semi-transparent.
Anode
[0153] The anode is usually anyone having a function as an
electrode of supplying holes into an organic layer, and is not
particularly limited in its shape, structure, size, or the like.
Further, depending on the use and purpose of the light emitting
element, the anode can be suitably selected from the known
electrode materials. As described above, the anode is usually
provided as a transparent anode.
Cathode
[0154] The cathode is usually any one having a function as an
electrode of injecting electrons to an organic layer, and is not
particularly limited in its shape, structure, size, or the like.
Further, depending on the use and purpose of the light emitting
element, the cathode can be suitably selected from the known
electrode materials.
Organic Layer
[0155] The organic electroluminescent element of the present
invention preferably has one or more organic layers disposed
between the electrodes and that include a light emitting layer,
wherein the light emitting layer contains a host material, and at
least one compound represented by the foregoing general formula
(1).
[0156] The organic layer is not particularly limited and can be
suitably selected depending on the use and purpose of the organic
electroluminescent element. However, the organic layer is
preferably formed on a transparent electrode or a semi-transparent
electrode. In this case, the organic layer is formed on the whole
surface or one surface of the transparent electrode or the
semi-transparent electrode.
[0157] The shape, the size, the thickness, or the like of the
organic layer are not particularly limited, and can be suitably
selected depending on the purpose.
[0158] Hereinbelow, the configuration of the organic layer, the
method for forming an organic layer, preferred embodiments of the
respective layers constituting the organic layer, and the materials
used in the respective layers in the organic electroluminescent
element of the present invention will be described in detail in
order.
Configuration of Organic Layer
[0159] In the organic electroluminescent element of the present
invention, the organic layer includes a light emitting layer. The
organic layer preferably includes a charge transporting layer. The
charge transporting layer refers to a layer in which charges move
when voltage is applied to the organic electroluminescent element.
Specific examples thereof include a hole injecting layer, a hole
transporting layer, an electron blocking layer, a light emitting
layer, a hole blocking layer, an electron transporting layer, and
an electron injecting layer. When the charge transporting layer is
a hole injecting layer, a hole transporting layer, an electron
blocking layer, or a light emitting layer, an organic
electroluminescent element with low cost as well as high efficiency
can be prepared.
[0160] The compound represented by the general formula (1) is
preferably contained in the light emitting layer in one or more
organic layers disposed between the electrodes of the organic
electroluminescent element.
[0161] The compound represented by the general formula (1) may be
contained in other organic layers of the organic electroluminescent
element of the present invention, provided that it does not depart
from the gist of the present invention. Examples of the organic
layer which may contain the compound represented by the general
formula (1), other than the light emitting layer, include a hole
injecting layer, a hole transporting layer, an electron
transporting layer, an electron injecting layer, an exciton
blocking layer, and a charge blocking layer (a hole blocking layer,
an electron blocking layer, and the like); preferably any one of an
exciton blocking layer, a charge blocking layer, an electron
transporting layer, and an electron injecting layer; and more
preferably an exciton blocking layer, a charge blocking layer, and
an electron transporting layer.
[0162] When the compound represented by the general formula (1) is
contained in the light emitting layer, the compound represented by
the general formula (1) is contained in the amount of preferably
0.1 to 100% by mass, more preferably 1 to 50% by mass, and still
more preferably 2 to 20% by mass, based on the total mass of the
light emitting layer. Particularly preferably, the compound is
contained in 3 to 10% by weight.
[0163] In a case where the compound represented by the general
formula (1) is contained in the organic layer other than the light
emitting layer, the compound represented by the general formula (1)
is contained in the amount of preferably 70 to 100% by mass, more
preferably 80 to 100% by mass, and still more preferably 90 to 100%
by mass, based on the total mass of the organic layer.
Method for Forming Organic Layer
[0164] The respective organic layers in the organic
electroluminescent element of the present invention can be suitably
formed by any of dry film forming methods such as a deposition
method and a sputtering method, wet type film forming methods
(solution coating methods) such as a transfer method, a printing
method, a spin-coating method, and a bar coating method.
[0165] In the organic electroluminescent element of the present
invention, the organic layer disposed between the pair of
electrodes is preferably formed by the deposition of a composition
that includes at least one layer of the compound represented by the
general formula (1).
Light Emitting Layer
[0166] The light emitting layer is a layer having a function of,
upon application of an electric field, receiving holes from the
anode, the hole injecting layer, or the hole transporting layer,
receiving electrons from the cathode, the electron injecting layer,
or the electron transporting layer, providing a recombination site
of the holes and the electrons, and causing light emitting.
However, the light emitting layer in the present invention is not
necessarily limited to the light emitting by such a mechanism.
[0167] The light emitting layer in the organic electroluminescent
element of the present invention may be constituted with only a
light emitting material such as the compound of the general formula
(1) or may be constituted as a mixed layer of a host material and a
light emitting material. The light emitting material may be made of
a single kind or two or more kinds. The host material is preferably
a charge transport material. The host material may be made of a
single kind or two or more kinds. Examples thereof include a
configuration in which an electron-transporting host material and a
hole-transporting host material are mixed. Furthermore, the light
emitting layer may contain a material which does not have charge
transporting properties and which does not emit light.
[0168] Moreover, the light emitting layer may be made of a single
layer or two or more layers. The respective layers may include the
same light emitting materials or host materials, and may also
include different materials from each other. In a case where plural
light emitting layers are present, the respective light emitting
layers may emit light in a different luminous color from each
other.
[0169] The thickness of the light emitting layer is not
particularly limited, but it is usually from 2 nm to 300 nm, and
among these, from the viewpoint of external quantum efficiency, it
is more preferably from 5 nm to 100 nm, and still more preferably
from 10 nm to 50 nm.
[0170] In the organic electroluminescent element of the present
invention, it is more preferable that the light emitting layer
contains the compound represented by the general formula (1) and
the compound represented by the general formula (1) is used as a
light emitting material of the light emitting layer. The host
material used in the present specification is a compound which
usually plays a role in injecting or transporting charges in the
light emitting layer and is also a compound which does not
substantially emit light in itself. As used herein, it is meant by
the terms "which does not substantially emit light" that the amount
of light emitting from the compound which does not substantially
emit light is preferably 5% or less, more preferably 3% or less,
and still more preferably 1% or less of the total amount of light
emitting in the whole of the element. The compound represented by
the general formula (1) may also be used as the host material of
the light emitting layer.
Light Emitting Material
[0171] In the organic electroluminescent element of the present
invention, the compound represented by the general formula (1) is
preferably used as a light emitting material, but even in this
case, it can also be used in combination with a light emitting
material other than the compound represented by the general formula
(1). In addition, in the organic electroluminescent element of the
present invention, even in a case where the compound represented by
the general formula (1) is used as a host material of a light
emitting layer or a case where it is used in the organic layer
other than the light emitting layer, a light emitting material
other than the compound represented by the general formula (1) may
be used in the light emitting layer.
[0172] The light emitting material that can be used in the present
invention is a fluorescent light emitting material. In addition,
the light emitting layer in the present invention can contain two
or more light emitting materials in order to improve color purity
or widen a light emitting wavelength region.
[0173] The fluorescent light emitting material that can be used in
the organic electroluminescent element of the present invention is
described in detail in, for example, Paragraph Nos. [0100] to of
JP-A-2008-270736, and Paragraph Nos. [0088] to [0090] of
JP-A-2007-266458, the detailed description of which can be applied
to the present invention.
[0174] The kind of the fluorescent light emitting material that can
be used in the present invention is not particularly limited, but
examples thereof include those other than the compound represented
by the general formula (1), for example, benzoxazole,
benzimidazole, benzothiazole, styrylbenzene, polyphenyl,
diphenylbutadiene, tetraphenylbutadiene, naphthalimide, coumarin,
pyrane, perinone, oxadiazole, aldazine, pyralizine,
cyclopentadiene, bis-styrylanthracene, quinacridone,
pyrrolopyridine, thiadiazolopyridine, cyclopentadiene, styrylamine,
aromatic fused polycyclic compounds (anthracene, phenanthroline,
pyrene, perylene, rubrene, pentacene, and the like), a variety of
metal complexes typified by metal complexes of 8-quinolinol,
pyrromethene complexes, and rare-earth complexes, polymer compounds
such as polythiophene, polyphenylene, and polyphenylenevinylene,
organic silanes, and derivatives thereof.
[0175] In addition, the compound described in [0082] of
JP-A-2010-111620 can also be used as a light emitting material.
[0176] The light emitting layer in the organic electroluminescent
element of the present invention may be constituted with only a
light emitting material or may be constituted as a mixed layer of a
host material and a light emitting material. The light emitting
material may be made of a single kind or two or more kinds. The
host material is preferably a charge transport material. The host
material may be made of a single kind or two or more kinds.
Examples thereof include a configuration in which an
electron-transporting host material and a hole-transporting host
material are mixed. Furthermore, the light emitting layer may
contain a material which does not have charge transporting
properties and which does not emit light.
[0177] Moreover, the light emitting layer may be made of a single
layer or two or more layers. The respective layers may include the
same light emitting materials or host materials, and may also
include different materials from each other. In a case where plural
light emitting layers are present, the respective light emitting
layers may emit light in different luminous colors from each
other.
Host Material
[0178] The host material is a compound that usually plays a role in
injecting or transporting charges in the light emitting layer and
is also a compound which does not substantially emit light in
itself. As used herein, it is meant by the terms "which does not
substantially emit light" that the amount of light emitting from
the compound which does not substantially emit light is preferably
5% or less, more preferably 3% or less, and still more preferably
1% or less of the total amount of light emitting in the whole of
the element.
[0179] Examples of the host material that can be used in the
organic electroluminescent element of the present invention include
the following compounds.
[0180] Conductive high-molecular oligomers such as pyrrole, indole,
carbazole, azaindole, azacarbazole, triazole, oxazole, oxadiazole,
pyrazole, imidazole, thiophene, benzothiophene, dibenzothiophene,
furan, benzofuran, dibenzofuran, polyarylalkane, pyrazoline,
pyrazolone, phenylenediamine, arylamine, amino-substituted
chalcone, styrylanthracene, fluorenone, hydrazone, stilbene,
silazane, aromatic tertiary amine compounds, styrylamine compounds,
porphyrin-based compounds, aromatic hydrocarbon compounds with
fused rings (fluorene, naphthalene, phenanthrene, triphenylene, and
the like), polysilane-based compounds, poly(N-vinylcarbazole),
aniline-based copolymers, thiophene oligomers, and polythiophene,
organic silanes, carbon films, pyridine, pyrimidine, triazine,
imidazole, pyrazole, triazole, oxazole, oxadiazole, fluorenone,
anthraquinodimethane, anthrone, diphenylquinone, thiopyran dioxide,
carbodiimide, fluorenylidenemethane, distyrylpyrazine,
fluorine-substituted aromatic compounds, heterocyclic
tetracarboxylic anhydrides such as naphthalene perylene,
phthalocyanine, and a variety of metal complexes typified by metal
complexes of 8-quinolinol derivatives and metal complexes having
metal phthalocyanine, benzoxazole, or benzothiazole as a ligand
thereof, and derivatives thereof (which may have a substituent or a
fused ring). In addition, the compounds described in [0081] or
[0083] of JP-A-2010-111620 can also be used.
[0181] Among these, carbazole, dibenzothiophene, dibenzofuran,
arylamine, aromatic hydrocarbon compounds with fused rings, and
metal complexes are preferred, and aromatic hydrocarbon compounds
with fused rings are particularly preferable since they are stable.
As the aromatic hydrocarbon compounds with fused rings,
naphthalene-based compounds, anthracene-based compounds,
phenanthrene-based compounds, triphenylene-based compounds, and
pyrene-based compounds are preferred; anthracene-based compounds
and pyrene-based compounds are more preferred; and anthracene-based
compounds are particularly preferred. As the anthracene-based
compounds, those described in [0033] to [0064] of WO 2010/134350
are particularly preferred, and examples thereof include Compounds
H-1 and H-2 as described later.
[0182] In the organic electroluminescent element of the present
invention, the host material contained in the light emitting layer
preferably has a hydrocarbon fused ring structure of 10 to 50
carbon atoms.
[0183] The hydrocarbon fused ring structure of 10 to 50 carbon
atoms is preferably naphthalene, phenanthrene,
benzo[c]phenanthrene, anthracene, pyrene, triphenylene, or
chrysene, more preferably naphthalene, phenanthrene,
benzo[c]phenanthrene, or anthracene, most preferably anthracene.
Specifically, the hydrocarbon fused ring structure of 10 to 50
carbon atoms in the host material is further preferably an
anthracene skeleton. Further, it is particularly preferable that
the hydrocarbon fused ring structure of 10 to 50 carbon atoms is a
compound configured from only carbon, and hydrogen or
deuterium.
[0184] The host material that can be used in the light emitting
layer in the organic electroluminescent element of the present
invention may be a host material having hole transporting
properties or a host material having electron transporting
properties.
[0185] In the light emitting layer, the singlet lowest excited
energy (S.sub.1 energy) in the film state of the host material is
preferably higher than the S.sub.1 energy of the light emitting
material in views of color purity, luminous efficiency, and driving
durability. The S.sub.1 of the host material is preferably higher
than the S.sub.1 of the light emitting material by 0.1 eV or more,
more preferably by 0.2 eV or more, and still more preferably by 0.3
eV or more.
[0186] When S.sub.1 in the film state of the host material is lower
than S.sub.1 of the light emitting material, the light emitting is
lost, and thus, the host material is required to have higher
S.sub.1 than the S.sub.1 of the light emitting material. Further,
even in a case where S.sub.1 of the host material is higher than
the S.sub.1 of the light emitting material, a small difference in
the S.sub.1 of the both leads to partial reverse energy movement
from the light emitting material to the host material, which causes
reduction in efficiency, color purity, or durability. Therefore,
there is a demand for a host material having a sufficiently high
S.sub.1, and high chemical stability and carrier
injecting/transporting properties.
[0187] Furthermore, the content of the host compound in the light
emitting layer in the organic electroluminescent element of the
present invention is not particularly limited, but from the
viewpoint of luminous efficiency and driving voltage, it is
preferably from 15 to 98% by mass, more preferably 80 to 97% by
mass based on the total mass of the compounds forming the light
emitting layer. When the light emitting layer includes plural kinds
of host compounds containing the compound represented by the
general formula (1), the content of the compound represented by the
general formula (1) is preferably from 50 to 99% by mass based on
the total host compounds.
Other Layers
[0188] The organic electroluminescent element of the present
invention may contain layers other than the light emitting
layer.
[0189] Examples of the organic layer other than the light emitting
layer which may be included in the organic layer include a hole
injecting layer, a hole transporting layer, a blocking layer (a
hole blocking layer, an exciton blocking layer, and the like), and
an electron transporting layer. Examples of the specific layer
configuration include those below, but the present invention is not
limited to these configurations. [0190] Anode/hole transporting
layer/light emitting layer/electron transporting layer/cathode,
[0191] Anode/hole transporting layer/light emitting layer/blocking
layer/electron transporting layer/cathode, [0192] Anode/hole
transporting layer/light emitting layer/blocking layer/electron
transporting layer/electron injecting layer/cathode, [0193]
Anode/hole injecting layer/hole transporting layer/light emitting
layer/blocking layer/electron transporting layer/cathode, [0194]
Anode/hole injecting layer/hole transporting layer/light emitting
layer/electron transporting layer/electron injecting layer/cathode,
[0195] Anode/hole injecting layer/hole transporting layer/light
emitting layer/blocking layer/electron transporting layer/electron
injecting layer/cathode, [0196] Anode/hole injecting layer/hole
transporting layer/blocking layer/light emitting layer/blocking
layer/electron transporting layer/electron injecting
layer/cathode.
[0197] The organic electroluminescent element of the present
invention preferably includes at least one layer of organic layers
that are preferably disposed between the (A) anode and the light
emitting layer. Examples of the organic layer that is preferably
disposed between the (A) anode and the light emitting layer include
an hole injecting layer, a hole transporting layer, and an electron
blocking layer from the anode side.
[0198] The organic electroluminescent element of the present
invention preferably includes at least one layer of organic layers
that are preferably disposed between the (B) cathode and the light
emitting layer. Examples of the organic layer that is preferably
disposed between the (B) cathode and the light emitting layer
include an electron injecting layer, an electron transporting
layer, and a hole blocking layer from the cathode side.
[0199] Specifically, an example of the preferred embodiments of the
organic electroluminescent element of the present invention is the
embodiment shown in FIG. 1, in which a hole injecting layer 4, a
hole transporting layer 5, a light emitting layer 6, a hole
blocking layer 7, and an electron transporting layer 8 are
laminated in this order as the organic layer from the anode 3
side.
[0200] Hereinbelow, these layers other than the light emitting
layer which the organic electroluminescent element of the present
invention may have will be described.
[0201] (A) Organic Layer Preferably Disposed Between Anode and
Light Emitting Layer
[0202] First, (A) the organic layer preferably disposed between the
anode and the light emitting layer will be described.
[0203] (A-1) Hole Injecting Layer and Hole Transporting Layer
[0204] The hole injecting layer and the hole transporting layer are
layers having a function of receiving holes from the anode or the
anode side and transporting them to the cathode side.
[0205] The light emitting element of the present invention
preferably includes at least one layer of organic layers between
the light emitting layer and the anode, and the organic layer
preferably includes at least one of compounds out of the compounds
represented by the following general formulae (Sa-1), (Sb-1), and
(Sc-1).
##STR00032##
(wherein X represents a substituted or unsubstituted alkylene group
having 1 to 30 carbon atoms, a substituted or unsubstituted
alkenylene group having 2 to 30 carbon atoms, a substituted or
unsubstituted arylene group having 6 to 30 carbon atoms, a
substituted or unsubstituted heteroarylene group having 2 to 30
carbon atoms, or a substituted or unsubstituted heterocyclic group
having 2 to 30 carbon atoms, or a group formed by a combination of
these groups. R.sup.S1, R.sup.S2, and R.sup.S3 each independently
represent a hydrogen atom, a substituted or unsubstituted alkyl
group having 1 to 30 carbon atoms, a substituted or unsubstituted
alkoxy group having 1 to 30 carbon atoms, a substituted or
unsubstituted aryl group having 6 to 30 carbon atoms, a substituted
or unsubstituted aryloxy group having 6 to 30 carbon atoms, a
substituted or unsubstituted heterocyclic ring having 2 to 30
carbon atoms, a substituted or unsubstituted fused polycyclic group
having 5 to 30 carbon atoms, a hydroxy group, a cyano group, or a
substituted or unsubstituted amino group. Adjacent R.sup.S1,
R.sup.S2, and R.sup.S3 may be bonded to each other to form a
saturated carbocycle or an unsaturated carbocycle. Ar.sup.S1 and
Ar.sup.S2 each independently represent a substituted or
unsubstituted aryl group having 6 to 30 carbon atoms, or a
substituted or unsubstituted heteroaryl group having 2 to 30 carbon
atoms).
##STR00033##
(wherein R.sup.S4, R.sup.S5, R.sup.S6, and R.sup.S7 each
independently represent a hydrogen atom, a substituted or
unsubstituted alkyl group having 1 to 30 carbon atoms, a
substituted or unsubstituted alkoxy group having 1 to 30 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 30
carbon atoms, a substituted or unsubstituted aryloxy group having 6
to 30 carbon atoms, a substituted or unsubstituted heterocyclic
ring having 2 to 30 carbon atoms, a substituted or unsubstituted
fused polycyclic group having 5 to 30 carbon atoms, a hydroxy
group, a cyano group, or a substituted or unsubstituted amino
group. Adjacent R.sup.S4, R.sup.S5, R.sup.S6, and R.sup.S7 may be
bonded to each other to form a saturated carbocycle or an
unsaturated carbocycle. Ar.sup.S3 represents a substituted or
unsubstituted aryl group having 6 to 30 carbon atoms, or a
substituted or unsubstituted heteroaryl group having 2 to 30 carbon
atoms).
##STR00034##
(wherein R.sup.S8 and R.sup.S9 each independently represent a
hydrogen atom, a substituted or unsubstituted alkyl group having 1
to 30 carbon atoms, a substituted or unsubstituted aryl group
having 6 to 30 carbon atoms, a substituted or unsubstituted
heterocyclic group having 2 to 30 carbon atoms, or a substituted or
unsubstituted fused polycyclic group having 5 to 30 carbon atoms.
R.sup.S10 represents a substituted or unsubstituted alkyl group
having 1 to 30 carbon atoms, a substituted or unsubstituted aryl
group having 6 to 30 carbon atoms, a substituted or unsubstituted
heterocyclic group having 2 to 30 carbon atoms, or a substituted or
unsubstituted fused polycyclic group having 5 to 30 carbon atoms.
R.sup.S11 and R.sup.S12 each independently represent a hydrogen
atom, a substituted or unsubstituted alkyl group having 1 to 30
carbon atoms, a substituted or unsubstituted alkoxy group having 1
to 30 carbon atoms, a substituted or unsubstituted aryl group
having 6 to 30 carbon atoms, a substituted or unsubstituted aryloxy
group having 6 to 30 carbon atoms, a substituted or unsubstituted
heterocyclic ring having 2 to 30 carbon atoms, a substituted or
unsubstituted fused polycyclic group having 5 to 30 carbon atoms, a
hydroxy group, a cyano group, or a substituted or unsubstituted
amino group. Adjacent R.sup.S11 and R.sup.S12 may be bonded to each
other to form a saturated carbocycle or an unsaturated carbocycle.
Ar.sup.S4 represents a substituted or unsubstituted aryl group
having 6 to 30 carbon atoms, or a substituted or unsubstituted
heteroaryl group having 2 to 30 carbon atoms. Y.sup.S1 and Y.sup.S2
each independently represent a substituted or unsubstituted
alkylene group having 1 to 30 carbon atoms, or a substituted or
unsubstituted arylene group having 6 to 30 carbon atoms. n and m
each independently represent an integer of 0 to 5).
[0206] The general formula (Sa-1) will be described.
[0207] In the general formula (Sa-1), X represents a substituted or
unsubstituted alkylene group having 1 to 30 carbon atoms, a
substituted or unsubstituted alkenylene group having 2 to 30 carbon
atoms, a substituted or unsubstituted arylene group having 6 to 30
carbon atoms, a substituted or unsubstituted heteroarylene group
having 2 to 30 carbon atoms, or a substituted or unsubstituted
heterocyclic group having 2 to 30 carbon atoms, or a group formed
by a combination of these groups. X is preferably a substituted or
unsubstituted arylene group having 6 to 30 carbon atoms, more
preferably a substituted or unsubstituted phenylene, a substituted
or unsubstituted biphenylene, and a substituted or unsubstituted
naphthylene, and still more preferably a substituted or
unsubstituted biphenylene.
[0208] R.sup.S1, R.sup.S2, and R.sup.S3 each independently
represent a hydrogen atom, a substituted or unsubstituted alkyl
group having 1 to 30 carbon atoms, a substituted or unsubstituted
alkoxy group having 1 to 30 carbon atoms, a substituted or
unsubstituted aryl group having 6 to 30 carbon atoms, a substituted
or unsubstituted aryloxy group having 6 to 30 carbon atoms, a
substituted or unsubstituted heterocyclic ring having 2 to 30
carbon atoms, a substituted or unsubstituted fused polycyclic group
having 5 to 30 carbon atoms, a hydroxy group, a cyano group, or a
substituted or unsubstituted amino group. Adjacent R.sup.S1,
R.sup.S2, and R.sup.S3 may be bonded to each other to form a
saturated carbocycle or an unsaturated carbocycle. Examples of the
saturated carbocycle or the unsaturated carbocycle include
naphthalene, azulene, anthracene, fluorene, and phenalene.
R.sup.S1, R.sup.S2, and R.sup.S3 are preferably a hydrogen atom, a
substituted or unsubstituted alkyl group having 1 to 30 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 30
carbon atoms, a substituted or unsubstituted fused polycyclic group
having 5 to 30 carbon atoms, or a cyano group, and more preferably
a hydrogen atom.
[0209] Ar.sup.S1 and Ar.sup.S2 each independently represent a
substituted or unsubstituted aryl group having 6 to 30 carbon
atoms, or a substituted or unsubstituted heteroaryl group having 2
to 30 carbon atoms. Ar.sup.S1 and Ar.sup.S2 are preferably a
substituted or unsubstituted phenyl group.
[0210] Next, the general formula (Sb-1) will be described.
[0211] In the general formula (Sb-1), R.sup.S4, R.sup.S5, R.sup.S6
and R.sup.S7 each independently represent a hydrogen atom, a
substituted or unsubstituted alkyl group having 1 to 30 carbon
atoms, a substituted or unsubstituted alkoxy group having 1 to 30
carbon atoms, a substituted or unsubstituted aryl group having 6 to
30 carbon atoms, a substituted or unsubstituted aryloxy group
having 6 to 30 carbon atoms, a substituted or unsubstituted
heterocyclic ring having 2 to 30 carbon atoms, or a substituted or
unsubstituted fused polycyclic group having 5 to 30 carbon atoms, a
hydroxy group, a cyano group, or a substituted or unsubstituted
amino group. Adjacent R.sup.S4, R.sup.S5, R.sup.S6 and R.sup.S7 may
be bonded to each other to form a saturated carbocycle or an
unsaturated carbocycle. Examples of the saturated carbocycle or the
unsaturated carbocycle include naphthalene, azulene, anthracene,
fluorene, and phenalene. R.sup.S4, R.sup.S5, R.sup.S6 and R.sup.S7
are preferably a hydrogen atom, a substituted or unsubstituted
alkyl group having 1 to 30 carbon atoms, a substituted or
unsubstituted aryl group having 6 to 30 carbon atoms, a substituted
or unsubstituted fused polycyclic group having 5 to 30 carbon
atoms, or a cyano group, and more preferably a hydrogen atom.
[0212] Ar.sup.S3 represents a substituted or unsubstituted aryl
group having 6 to 30 carbon atoms, or a substituted or
unsubstituted heteroaryl group having 2 to 30 carbon atoms.
Ar.sup.S3 is preferably a substituted or unsubstituted phenyl
group.
[0213] Next, the general formula (Sc-1) will be described.
[0214] In the general formula (Sc-1), R.sup.S8 and R.sup.S9 each
independently represent a hydrogen atom, a substituted or
unsubstituted alkyl group having 1 to 30 carbon atoms, a
substituted or unsubstituted aryl group having 6 to 30 carbon
atoms, a substituted or unsubstituted heterocyclic group having 2
to 30 carbon atoms, or a substituted or unsubstituted fused
polycyclic group having 5 to 30 carbon atoms. R.sup.S8 and R.sup.S9
are preferably a substituted or unsubstituted alkyl group having 1
to 30 carbon atoms, or a substituted or unsubstituted aryl group
having 6 to 30 carbon atoms, and more preferably a methyl group or
a phenyl group. R.sup.S10 is a substituted or unsubstituted alkyl
group having 1 to 30 carbon atoms, a substituted or unsubstituted
aryl group having 6 to 30 carbon atoms, a substituted or
unsubstituted heterocyclic group having 2 to 30 carbon atoms, or a
substituted or unsubstituted fused polycyclic group having 5 to 30
carbon atoms. R.sup.S10 is preferably a substituted or
unsubstituted aryl group having 6 to 30 carbon atoms, and more
preferably a phenyl group. R.sup.S11 and R.sup.S12 each
independently represent a hydrogen atom, a substituted or
unsubstituted alkyl group having 1 to 30 carbon atoms, a
substituted or unsubstituted alkoxy group having 1 to 30 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 30
carbon atoms, a substituted or unsubstituted aryloxy group having 6
to 30 carbon atoms, a substituted or unsubstituted heterocyclic
ring having 2 to 30 carbon atoms, a substituted or unsubstituted
fused polycyclic group having 5 to 30 carbon atoms, a hydroxy
group, a cyano group, or a substituted or unsubstituted amino
group. Adjacent R.sup.S11 and R.sup.S12 may be bonded to each other
to form a saturated carbocycle or an unsaturated carbocycle.
Examples of the saturated carbocycle or the unsaturated carbocycle
include naphthalene, azulene, anthracene, fluorene, and phenalene.
R.sup.S11 and R.sup.S12 are preferably a hydrogen atom, a
substituted or unsubstituted alkyl group having 1 to 30 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 30
carbon atoms, a substituted or unsubstituted fused polycyclic group
having 5 to 30 carbon atoms, or a cyano group, and more preferably
a hydrogen atom. Ar.sup.S4 represents a substituted or
unsubstituted aryl group having 6 to 30 carbon atoms, or a
substituted or unsubstituted heteroaryl group having 2 to 30 carbon
atoms. Y.sup.S1 and Y.sup.S2 represent substituted or unsubstituted
alkylene having 1 to 30 carbon atoms, or substituted or
unsubstituted arylene having 6 to 30 carbon atoms. Y.sup.S1 and
Y.sup.S2 are preferably substituted or unsubstituted arylene having
6 to 30 carbon atoms, and more preferably substituted or
unsubstituted phenylene. n is an integer of 0 to 5, preferably 0 to
3, more preferably 0 to 2, and still more preferably 0. m is an
integer of 0 to 5, preferably 0 to 3, more preferably 0 to 2, and
still more preferably 1.
[0215] The general formula (Sa-1) is preferably a compound
represented by the following general formula (Sa-2).
##STR00035##
(wherein R.sup.Sl, R.sup.S2, and R.sup.S3 each independently
represent a hydrogen atom, a substituted or unsubstituted alkyl
group having 1 to 30 carbon atoms, a substituted or unsubstituted
alkoxy group having 1 to 30 carbon atoms, a substituted or
unsubstituted aryl group having 6 to 30 carbon atoms, a substituted
or unsubstituted aryloxy group having 6 to 30 carbon atoms, a
substituted or unsubstituted heterocyclic ring having 2 to 30
carbon atoms, a substituted or unsubstituted fused polycyclic group
having 5 to 30 carbon atoms, a hydroxy group, a cyano group, or a
substituted or unsubstituted amino group. Adjacent R.sup.S1,
R.sup.S2, R.sup.S3 may be bonded to each other to form a saturated
carbocycle or an unsaturated carbocycle. Q.sup.Sa each
independently represent a hydrogen atom, a cyano group, a fluorine
atom, an alkoxy group having 1 to 30 carbon atoms, a substituted or
unsubstituted alkyl group having 1 to 30 carbon atoms, an aryloxy
group having 6 to 30 carbon atoms, a substituted or unsubstituted
aryl group having 6 to 30 carbon atoms, a substituted or
unsubstituted heterocyclic ring having 2 to 30 carbon atoms, or a
substituted or unsubstituted amino group).
[0216] The general formula (Sa-2) will be described. R.sup.S1,
R.sup.S2, and R.sup.S3 have the same definitions as those in the
general formula (Sa-1), and their preferred ranges are also the
same. Each Q.sup.Sa independently represents a hydrogen atom, a
cyano group, a fluorine atom, an alkoxy group having 1 to 30 carbon
atoms, a substituted or unsubstituted alkyl group having 1 to 30
carbon atoms, an aryloxy group having 6 to 30 carbon atoms, a
substituted or unsubstituted aryl group having 6 to 30 carbon
atoms, a substituted or unsubstituted heterocyclic ring having 2 to
30 carbon atoms, or a substituted or unsubstituted amino group.
Q.sup.Sa is preferably a hydrogen atom, a cyano group, a fluorine
atom, a substituted or unsubstituted alkyl group having 1 to 30
carbon atoms, or a substituted or unsubstituted aryl group having 6
to 30 carbon atoms, more preferably a hydrogen atom or a
substituted or unsubstituted alkyl group having 1 to 30 carbon
atoms, and still more preferably a hydrogen atom.
[0217] The general formula (Sb-1) is preferably a compound
represented by the following general formula (Sb-2).
##STR00036##
(wherein R.sup.S4, R.sup.S5, R.sup.S6 and R.sup.S7 each
independently represent a hydrogen atom, a substituted or
unsubstituted alkyl group having 1 to 30 carbon atoms, a
substituted or unsubstituted alkoxy group having 1 to 30 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 30
carbon atoms, a substituted or unsubstituted aryloxy group having 6
to 30 carbon atoms, a substituted or unsubstituted heterocyclic
ring having 2 to 30 carbon atoms, a substituted or unsubstituted
fused polycyclic group having 5 to 30 carbon atoms, a hydroxy
group, a cyano group, or a substituted or unsubstituted amino
group. Adjacent R.sup.S4, R.sup.S5, R.sup.S6 and R.sup.S7 may be
bonded to each other to form a saturated carbocycle or an
unsaturated carbocycle. Q.sup.Sb represents a hydrogen atom, a
cyano group, a fluorine atom, an alkoxy group having 1 to 30 carbon
atoms, a substituted or unsubstituted alkyl group having 1 to 30
carbon atoms, an aryloxy group having 6 to 30 carbon atoms, a
substituted or unsubstituted aryl group having 6 to 30 carbon
atoms, a substituted or unsubstituted heterocyclic ring having 2 to
30 carbon atoms, or a substituted or unsubstituted amino
group).
[0218] The general formula (Sb-2) will be described. R.sup.S4,
R.sup.S5, R.sup.S6 and R.sup.S7 have the same definitions as those
in the general formula (Sb-1), and their preferred ranges are also
the same. Q.sup.Sb represents a hydrogen atom, a cyano group, a
fluorine atom, an alkoxy group having 1 to 30 carbon atoms, a
substituted or unsubstituted alkyl group having 1 to 30 carbon
atoms, an aryloxy group having 6 to 30 carbon atoms, a substituted
or unsubstituted aryl group having 6 to 30 carbon atoms, a
substituted or unsubstituted heterocyclic ring having 2 to 30
carbon atoms, or a substituted or unsubstituted amino group.
Q.sup.Sb is preferably a hydrogen atom, a cyano group, a fluorine
atom, a substituted or unsubstituted alkyl group having 1 to 30
carbon atoms, or a substituted or unsubstituted aryl group having 6
to 30 carbon atoms, more preferably a hydrogen atom, or a
substituted or unsubstituted alkyl group having 1 to 30 carbon
atoms, and still more preferably a hydrogen atom.
[0219] The general formula (Sc-1) is preferably a compound
represented by the following general formula (Sc-2).
##STR00037##
(wherein R.sup.S8 and R.sup.S9 each independently represent a
hydrogen atom, a substituted or unsubstituted alkyl group having 1
to 30 carbon atoms, a substituted or unsubstituted aryl group
having 6 to 30 carbon atoms, a substituted or unsubstituted
heterocyclic group having 2 to 30 carbon atoms, or a substituted or
unsubstituted fused polycyclic group having 5 to 30 carbon atoms.
R.sup.S10 represents a substituted or unsubstituted alkyl group
having 1 to 30 carbon atoms, a substituted or unsubstituted aryl
group having 6 to 30 carbon atoms, a substituted or unsubstituted
heterocyclic group having 2 to 30 carbon atoms, or a substituted or
unsubstituted fused polycyclic group having 5 to 30 carbon atoms.
R.sup.S11 and R.sup.S12 each independently represent a hydrogen
atom, a substituted or unsubstituted alkyl group having 1 to 30
carbon atoms, a substituted or unsubstituted alkoxy group having 1
to 30 carbon atoms, a substituted or unsubstituted aryl group
having 6 to 30 carbon atoms, a substituted or unsubstituted aryloxy
group having 6 to 30 carbon atoms, a substituted or unsubstituted
heterocyclic ring having 2 to 30 carbon atoms, or a substituted or
unsubstituted fused polycyclic group having 5 to 30 carbon atoms, a
hydroxy group, a cyano group, or a substituted or unsubstituted
amino group. Adjacent R.sup.S11 and R.sup.S12 may be bonded to each
other to form a saturated carbocycle or an unsaturated carbocycle.
Q.sup.Sc represents a hydrogen atom, a cyano group, a fluorine
atom, an alkoxy group having 1 to 30 carbon atoms, a substituted or
unsubstituted alkyl group having 1 to 30 carbon atoms, an aryloxy
group having 6 to 30 carbon atoms, a substituted or unsubstituted
aryl group having 6 to 30 carbon atoms, a substituted or
unsubstituted heterocyclic ring having 2 to 30 carbon atoms, or a
substituted or unsubstituted amino group).
[0220] The general formula (Sc-2) will be described. R.sup.S8,
R.sup.S9, R.sup.S10, R.sup.S11 and R.sup.S12 have the same
definitions as those in the general formula (Sc-1), and their
preferred ranges are also the same. Q.sup.Sc represents a hydrogen
atom, a cyano group, a fluorine atom, an alkoxy group having 1 to
30 carbon atoms, a substituted or unsubstituted alkyl group having
1 to 30 carbon atoms, an aryloxy group having 6 to 30 carbon atoms,
a substituted or unsubstituted aryl group having 6 to 30 carbon
atoms, a substituted or unsubstituted heterocyclic ring having 2 to
30 carbon atoms, or a substituted or unsubstituted amino group.
Q.sup.Sc is preferably a hydrogen atom, a cyano group, a fluorine
atom, a substituted or unsubstituted alkyl group having 1 to 30
carbon atoms, or a substituted or unsubstituted aryl group having 6
to 30 carbon atoms, more preferably a hydrogen atom, or a
substituted or unsubstituted aryl group having 6 to 30 carbon
atoms, and still more preferably a phenyl group.
[0221] Specific examples of the compounds represented by the
general formulae (Sa-1), (Sb-1), and (Sc-1) include the following
ones. However, the present invention is not limited to the
following specific examples.
##STR00038## ##STR00039## ##STR00040## ##STR00041## ##STR00042##
##STR00043## ##STR00044## ##STR00045## ##STR00046## ##STR00047##
##STR00048##
[0222] The compound represented by the general formula (Sa-1),
(Sb-1), or (Sc-1) can be synthesized by the method described in
JP-A-2007-318101. After the synthesis, purification is preferably
carried out by column chromatography, recrystallization,
reprecipitation, or the like, and then by sublimation purification.
By the sublimation purification, organic impurities can be
separated and inorganic salts, residual solvents, moisture, or the
like can be removed effectively.
[0223] In the light emitting element of the present invention, the
compound represented by the general formula (Sa-1), (Sb-1), or
(Sc-1) is preferably included in the organic layer between the
light emitting layer and the anode, and among these, it is more
preferably included in the layer on the anode side adjacent to the
light emitting layer, and it is particularly preferably a hole
transporting material included in the hole transporting layer.
[0224] The compound represented by the general formula (Sa-1),
(Sb-1), or (Sc-1) is preferably contained in the amount of 70 to
100% by mass, and more preferably 85 to 100% by mass, based on the
total mass of the organic layer added.
Compound Represented by General Formula (M-3)
[0225] The organic electroluminescent element of the present
invention is a material which is particularly preferably used in an
organic layer, preferably disposed between the (A) anode and the
light emitting layer, and examples thereof include at least one
kind of the compound represented by the following general formula
(M-3).
[0226] The compound represented by the general formula (M-3) is
more preferably contained in the organic layer adjacent to the
light emitting layer between the light emitting layer and the
anode, but it is not limited in its uses and may be further
contained in any of other layers in the organic layer. The layer to
which the compound represented by the general formula (M-3) is
introduced may be any one or plural layers of a light emitting
layer, a hole injecting layer, a hole transporting layer, an
electron transporting layer, an electron injecting layer, and a
charge blocking layer.
[0227] The organic layer adjacent to the light emitting layer
between the light emitting layer and the anode, which contains the
compound represented by the general formula (M-3), is more
preferably an electron blocking layer or a hole transporting
layer.
##STR00049##
[0228] In the general formula (M-3), R.sup.S1 to R.sup.S5 each
independently represent an alkyl group, a cycloalkyl group, an
alkenyl group, an alkynyl group, --CN, a perfluoroalkyl group, a
trifluorovinyl group, --CO.sub.2R, --C(O)R, --NR.sup.2, --NO.sub.2,
--OR, a halogen atom, an aryl group, or an heteroaryl group, and
may also have a substituent Z. R's each independently represent a
hydrogen atom, an alkyl group, a perhaloalkyl group, an alkenyl
group, an alkynyl group, a heteroalkyl group, an aryl group, or a
heteroaryl group. When plural R.sup.S1's to R.sup.S5's are present,
they may be bonded to each other to form a ring and further have a
substituent Z.
[0229] a represents an integer of 0 to 4, and when plural
R.sup.S1's are present, they may be the same as or different from
each other and may be bonded to each other to form a ring. b to e
each independently represent an integer of 0 to 5, and when each of
plural R.sup.S2's to R.sup.S5's are present, they may be the same
as or different from each other, and any two out of them may be
bonded to each other to form a ring.
[0230] q is an integer of 1 to 5, and when q is 2 or more, the
plural R.sup.S1's may be the same as or different from each other,
and may be bonded to each other to form a ring.
[0231] The alkyl group may have a substituent and may be saturated
or unsaturated. Examples of the group which may be used for
substitution include the above-described substituents Z. Examples
of the alkyl group represented by R.sup.S1 to R.sup.S5 preferably
include alkyl groups having 1 to 8 carbon atoms in total, and more
preferably alkyl groups having 1 to 6 carbon atoms in total, for
example, a methyl group, an ethyl group, an i-propyl group, a
cyclohexyl group, and a t-butyl group.
[0232] The cycloalkyl group may have a substituent, and may be
saturated or unsaturated. Examples of the group which may be used
for substitution include the above-described substituents Z.
Examples of the cycloalkyl group represented by R.sup.S1 to
R.sup.S5 preferably include cycloalkyl groups having a number of
the ring members of 4 to 7, and more preferably cycloalkyl groups
having 5 to 6 carbon atoms in total, for example, a cyclopentyl
group and a cyclohexyl group.
[0233] Examples of the alkenyl group represented by R.sup.S1 to
R.sup.S5 include ones preferably having 2 to 30 carbon atoms, more
preferably 2 to 20 carbon atoms, and particularly preferably 2 to
10 carbon atoms, for example, vinyl, allyl, 1-propenyl,
1-isopropenyl, 1-butenyl, 2-butenyl, and 3-pentenyl.
[0234] Examples of the alkynyl group represented by R.sup.S1 to
R.sup.S5 include ones preferably having 2 to 30 carbon atoms, more
preferably 2 to 20 carbon atoms, and particularly preferably 2 to
10 carbon atoms, for example, ethynyl, propargyl, 1-propynyl, and
3-pentynyl.
[0235] Examples of the perfluoroalkyl group represented by R.sup.S1
to R.sup.S5 include those in which all the hydrogen atoms of the
above-described alkyl group are substituted with fluorine
atoms.
[0236] Preferred examples of the aryl group represented by R.sup.S1
to R.sup.S5 include a substituted or unsubstituted aryl group
having 6 to 30 carbon atoms, for example, a phenyl group, a tolyl
group, a biphenyl group, a terphenyl group.
[0237] The heteroaryl group represented by R.sup.S1 to R.sup.S5 is
preferably a heteroaryl group having 5 to 8 carbon atoms, and more
preferably a 5- or 6-membered substituted or unsubstituted
heteroaryl group, and examples thereof include a pyridyl group, a
pyrazinyl group, a pyridazinyl group, a pyrimidinyl group, a
triazinyl group, a quinolinyl group, an isoquinolinyl group, a
quinazolinyl group, a cinnolinyl group, a phthalazinyl group, a
quinoxalinyl group, a pyrrolyl group, an indolyl group, a furyl
group, a benzofuryl group, a thienyl group, a benzothienyl group, a
pyrazolyl group, an imidazolyl group, a benzimidazolyl group, a
triazolyl group, an oxazolyl group, a benzoxazolyl group, a
triazolyl group, a benzothiazolyl group, an isothiazolyl group, a
benzisothiazolyl group, a thiadiazolyl group, an isoxazolyl group,
a benzisoxazolyl group, a pyrrolidinyl, piperidinyl group, a
piperadinyl group, an imidazolidinyl group, a thiazolinyl group, a
sulfolanyl group, a carbazolyl group, a dibenzofuryl group, a
dibenzothienyl group, and a pyridindolyl group. Preferred examples
thereof include a pyridyl group, a pyrimidinyl group, an imidazolyl
group, and a thienyl group, and more preferably a pyridyl group and
a pyrimidinyl group.
[0238] R.sup.S1 to R.sup.S5 are preferably a hydrogen atom, an
alkyl group, a cyano group, a trifluoromethyl group, a
perfluoroalkyl group, a dialkylamino group, a fluoro group, an aryl
group, a heteroaryl group, more preferably a hydrogen atom, an
alkyl group, a cyano group, a trifluoromethyl group, a fluoro
group, and an aryl group, and still more preferably a hydrogen
atom, an alkyl group, and an aryl group. As the substituent Z, an
alkyl group, an alkoxy group, a fluoro group, a cyano group, and a
dialkylamino group are preferred, and a hydrogen atom and an alkyl
group are more preferred.
[0239] Any two of R.sup.S1 to R.sup.S5 may be bonded to form a
fused 4- to 7-membered ring, and the fused 4- to 7-membered ring is
cycloalkyl, aryl, or heteroaryl, and the fused 4- to 7-membered
ring may further have a substituent Z. The definitions and
preferred ranges of the cycloalkyl, aryl, and heteroaryl thus
formed are the same as for the cycloalkyl group, the aryl group,
and the heteroaryl group defined by R.sup.S1 to R.sup.S5.
[0240] In a case where the compound represented by the general
formula (M-3) is used in a hole transporting layer, the compound
represented by the general formula (M-3) is preferably contained in
the amount of 50 to 100% by mass, more preferably 80 to 100% by
mass, and particularly preferably 95 to 100% by mass.
[0241] In addition, in a case where the compound represented by the
general formula (M-3) is used in plural organic layers, the
compound is preferably contained in an amount of the
above-described range in each layer.
[0242] The thickness of the hole transporting layer including the
compound represented by the general formula (M-3) is preferably
from 1 nm to 500 nm, more preferably from 3 nm to 200 nm, and still
more preferably from 5 nm to 100 nm. Further, the hole transporting
layer is preferably provided to be adjacent to the light emitting
layer.
[0243] Specific examples of the compound represented by the general
formula (M-3) are shown below, but the present invention is not
limited thereto.
##STR00050## ##STR00051## ##STR00052## ##STR00053## ##STR00054##
##STR00055## ##STR00056## ##STR00057## ##STR00058##
[0244] In addition, the detailed description on the hole injecting
layer and the hole transporting layer in Paragraph Nos. [0165] to
[0167] of JP-A-2008-270736 can also be applied to the present
invention. Further, the detailed description in [0250] to [0339] of
JP-A-2011-71452 can also be applied to the hole injecting layer and
the hole transporting layer of the present invention.
[0245] The hole injecting layer preferably contains an electron
receptive dopant. By incorporating the electron receptive dopant in
the hole injecting layer, there are effects in which, for example,
the hole injecting properties are improved, the driving voltage is
lowered, and the efficiency is improved. The electron receptive
dopant may be any one of organic materials and inorganic materials
as long as it is capable of withdrawing electrons from doped
material and generating radical cations, and examples thereof
include tetracyanoquinodimethane (TCNQ) and TCNQ compounds such as
tetrafluorotetracyanoquinodimethane (F.sub.4-TCNQ),
hexaazatriphenylene compounds such as hexacyanohexaazatriphenylene
(HAT-CN, compound LG 101 used in the Examples below), and
molybdenum oxide.
[0246] The electron receptive dopant in the hole injecting layer is
preferably contained in the amount of 0.01 to 50% by mass, more
preferably 0.1 to 40% by mass, and still more preferably 0.2 to 30%
by mass, based on the total mass of the compounds forming the hole
injecting layer.
[0247] (A-2) Electron Blocking Layer
[0248] The electron blocking layer is a layer having a function of
preventing the electrons, which have been transported from the
cathode side to the light emitting layer, from passing through to
the anode side. In the present invention, the electron blocking
layer can be provided as an organic layer adjacent to the light
emitting layer on the anode side.
[0249] As the organic compound constituting the electron blocking
layer, those exemplified above as the hole transporting materials
can be used.
[0250] The thickness of the electron blocking layer is preferably
from 1 nm to 500 nm, more preferably from 3 nm to 100 nm, and still
more preferably from 5 nm to 50 nm.
[0251] The electron blocking layer may have either a single layer
structure composed of one or more materials selected from the
above-exemplified materials or a multilayer structure composed of a
plurality of layers having the same composition or different
compositions.
[0252] The material used in the electron blocking layer preferably
has higher S.sub.1 energy than that of the light emitting material
in views of color purity, luminous efficiency, and driving
durability. The S.sub.1 in the film state of the material used in
the electron blocking layer is preferably higher than the S.sub.1
of the light emitting material by 0.1 eV or more, more preferably
by 0.2 eV or more, and still more preferably by 0.3 eV or more.
[0253] (B) Organic Layer Preferably Disposed Between Cathode and
Light Emitting Layer
[0254] First, the (B) organic layer preferably disposed between the
cathode and the light emitting layer will be described.
(B-1) Electron Injecting Layer and Electron Transporting Layer
[0255] The electron injecting layer and the electron transporting
layer are layers having a function of receiving electrons from the
cathode or the cathode side and transporting them to the anode
side. The electron injecting material and the electron transporting
material used in these layers may be either a low-molecular
compound or a high-molecular compound.
[0256] As the electron transporting material, for example, the
compound represented by the general formula (1) can be used. As the
other electron transporting materials, any one selected from
aromatic ring tetracarboxylic acid anhydrides, such as pyridine
derivatives, quinoline derivatives, pyrimidine derivatives,
pyrazine derivatives, phthalazine derivatives, phenanthroline
derivatives, triazine derivatives, triazole derivatives, oxazole
derivatives, oxadiazole derivatives, imidazole derivatives,
benzimidazole derivatives, imidazopyridine derivatives, fluorenone
derivatives, anthraquinodimethane derivatives, anthrone
derivatives, diphenylquinone derivatives, thiopyranedioxide
derivatives, carbodiimide derivatives, fluorenylidenemethane
derivatives, distyrylpyrazine derivatives, naphthalene, and
perylene; various metal complexes typified by metal complexes of
phthalocyanine derivatives or 8-quinolinol derivatives and metal
complexes having metal phthalocyanine, benzoxazole, or
benzothiazole as a ligand thereof, organic silane derivatives
typified by silol, hydrocarbon compounds with fused rings, such as
naphthalene, anthracene, phenanthrene, triphenylene, and pyrene is
preferred, and any one selected from pyridine derivatives,
benzimidazole derivatives, imidazopyridine derivatives, metal
complexes, and hydrocarbon compounds with fused rings is more
preferred.
[0257] The thickness of each of the electron injecting layer and
the electron transporting layer is preferably 500 nm or less from
the viewpoint that the driving voltage is decreased.
[0258] The thickness of the electron transporting layer is
preferably from 1 nm to 500 nm, more preferably from 5 nm to 200
nm, and still more preferably from 10 nm to 100 nm. The thickness
of the electron injecting layer is preferably from 0.1 nm to 200
nm, more preferably from 0.2 nm to 100 nm, and still more
preferably from 0.5 nm to 50 nm.
[0259] The electron injecting layer and the electron transporting
layer may have either a single layer structure composed of one or
more materials selected from the above-exemplified materials or a
multilayer structure composed of a plurality of layers having the
same composition or different compositions.
[0260] The electron injecting layer preferably contains an electron
donating dopant. By incorporating the electron donating dopant in
the electron injecting layer, there are effects that, for example,
the electron injecting properties are improved, the driving voltage
is lowered, and the efficiency is improved. The electron donating
dopant may be any one of organic materials and inorganic materials
as long as it is capable of giving electrons to the material to be
doped and generating radical anions, and examples thereof include
dihydroimidazole compounds such as tetrathiafulvalene (TTF),
tetrathianaphthacene (TTT), and
bis-[1,3-diethyl-2-methyl-1,2-dihydrobenzimidazolyl], lithium, and
cesium.
[0261] The electron donating dopant in the electron injecting layer
is preferably contained in the amount of 0.01 to 50% by mass, more
preferably 0.1 to 40% by mass, and still more preferably 0.5 to 30%
by mass, based on the total mass of the compounds forming the
electron injecting layer.
(B-2) Hole Blocking Layer
[0262] The hole blocking layer is a layer having a function of
preventing holes, which have been transported from the anode side
to the light emitting layer, from passing through to the cathode
side. In the present invention, the hole blocking layer can be
provided as an organic layer adjacent to the light emitting layer
on the cathode side.
[0263] In order that the S.sub.1 energy of the organic compound in
the film state constituting the hole blocking layer prevents the
energy movement of excitons produced in the light emitting layer,
and thus, does not lower the luminous efficiency, it is preferably
higher than S.sub.1 energy of the light emitting material.
[0264] As one example of the organic compound constituting the hole
blocking layer, for example, the compound represented by the
general formula (1) can be used.
[0265] Examples of the organic compounds constituting the hole
blocking layer, other than the compound represented by the general
formula (1), include aluminum complexes such as aluminum (III)
bis(2-methyl-8-quinolinato) 4-phenylphenolate (abbreviated as
"BAlq"), triazole derivatives, and phenanthroline derivatives such
as 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (abbreviated as
"BCP").
[0266] The thickness of the hole blocking layer is preferably from
1 nm to 500 nm, more preferably from 3 nm to 100 nm, and still more
preferably from 5 nm to 50 nm.
[0267] The hole blocking layer may have either a single layer
structure composed of one or more materials selected from the
above-exemplified materials or a multilayer structure composed of a
plurality of layers having the same composition or different
compositions.
[0268] The material used in the hole blocking layer preferably has
higher S.sub.1 energy than that of the light emitting material in
views of color purity, luminous efficiency, and driving durability.
The S.sub.1 in the film state of the material used in the hole
blocking layer is preferably higher than the S.sub.1 of the light
emitting material by 0.1 eV or more, more preferably by 0.2 eV or
more, and still more preferably by 0.3 eV or more.
(B-3) Material which is Particularly Preferably Used in Organic
Layer, Preferably Disposed Between Cathode and Light Emitting
Layer
[0269] For the organic electroluminescent element of the present
invention, examples of the material which is particularly
preferably used in the materials for an organic layer, preferably
disposed between the (B) cathode and the light emitting layer
include the compound represented by the general formula (1), a
compound represented by the following general formula (P-1), and a
compound represented by the following general formula (O-1).
[0270] Hereinafter, a compound represented by the general formula
(O-1) and a compound represented by the general formula (P-1) will
be described.
[0271] The organic electroluminescent element of the present
invention preferably includes at least one layer of organic layers
between the light emitting layer and the cathode, and the organic
layer preferably contains at least one of compounds represented by
the following general formula (O-1), from the viewpoint of
efficiency or driving voltage of an element. Hereinafter, the
general formula (O-1) will be described.
##STR00059##
[0272] (In the general formula (O-1), R.sup.O1 represents an alkyl
group, an aryl group, or a heteroaryl group. A.sup.O1 to A.sup.O4
each independently represent C--R.sup.A or a nitrogen atom. R.sup.A
represents a hydrogen atom, an alkyl group, an aryl group, or a
heteroaryl group, and plural R.sup.A's may be the same as or
different from each other. L.sup.O1 represents any of divalent to
hexavalent linking groups with an aryl ring or a heteroaryl ring.
n.sup.O1 represents an integer of 2 to 6).
[0273] R.sup.O1 represents an alkyl group (preferably having 1 to 8
carbon atoms), an aryl group (preferably having 6 to 30 carbon
atoms), or a heteroaryl group (preferably having 4 to 12 carbon
atoms), which may have a substituent selected from the
above-described Substituent Group A. R.sup.O1 is preferably an aryl
group or a heteroaryl group, and more preferably an aryl group.
Preferred examples of the substituent in a case where the aryl
group of R.sup.O1 has a substituent include an alkyl group, an aryl
group, and a cyano group, more preferably an alkyl group and an
aryl group, and still more preferably an aryl group. In a case
where the aryl group of R.sup.O1 has plural substituents, the
plural substituents may be bonded to each other to form a 5- or
6-membered ring. The aryl group of R.sup.O1 is preferably a phenyl
group which may have a substituent selected from Substituent Group
A, more preferably a phenyl group which may be substituted with an
alkyl group or an aryl group, and still more preferably an
unsubstituted phenyl group or 2-phenylphenyl group.
[0274] A.sup.O1 to A.sup.O4 each independently represent C--R.sup.A
or a nitrogen atom. It is preferable that 0 to 2 out of A.sup.O1 to
A.sup.O4 be nitrogen atoms; and it is more preferable that 0 or 1
out of A.sup.O1 to A.sup.O4 be nitrogen atoms. It is preferable
that all of A.sup.O1 to A.sup.O4 be C--R.sup.A, or A.sup.O1 is a
nitrogen atom, and A.sup.O2 to A.sup.O4 are C--R.sup.A; it is more
preferable that A.sup.O1 is a nitrogen atom, and A.sup.O2 to
A.sup.O4 are C--R.sup.A; it is still more preferable that A.sup.O1
is a nitrogen atom, A.sup.O2 to A.sup.O4 are C--R.sup.A, and
R.sup.A's are all hydrogen atoms.
[0275] R.sup.A represents a hydrogen atom, an alkyl group
(preferably having 1 to 8 carbon atoms), an aryl group (preferably
having 6 to 30 carbon atoms), or a heteroaryl group (preferably
having 4 to 12 carbon atoms), and may have a substituent selected
from the above-described Substituent Group A. Further, plural
R.sup.A's may be the same as or different from each other. R.sup.A
is preferably a hydrogen atom or an alkyl group, and more
preferably a hydrogen atom.
[0276] L.sup.O1 represents a divalent to hexavalent linking group
including an aryl ring (preferably having 6 to 30 carbon atoms) or
a heteroaryl ring (preferably having 4 to 12 carbon atoms).
L.sup.O1 is preferably an arylene group, a heteroarylene group, an
aryltriyl group, or a heteroaryltriyl group, more preferably a
phenylene group, a biphenylene group, or a benzenetriyl group, and
still more preferably a biphenylene group or a benzenetriyl group.
L.sup.O1 may have a substituent selected from the above-described
Substituent Group A, and in a case of having the substituent, the
substituent is preferably an alkyl group, an aryl group, or a cyano
group. Specific examples of L.sup.O1 include the following.
##STR00060## ##STR00061##
[0277] n.sup.O1 represents an integer of 2 to 6, preferably an
integer of 2 to 4, and more preferably 2 or 3. n.sup.O1 is most
preferably 3 from the viewpoint of the efficiency of an element, or
most preferably 2 from the viewpoint of the durability of an
element.
[0278] The glass transition temperature (Tg) of the compound
represented by the general formula (O-1) is preferably from
100.degree. C. to 300.degree. C., more preferably from 120.degree.
C. to 300.degree. C., still more preferably from 120.degree. C. to
300.degree. C., and even still more preferably from 140.degree. C.
to 300.degree. C., from the viewpoint of stability during storage
at a high temperature, or stable operation during driving at a high
temperature or against heat generation during driving.
[0279] Specific examples of the compound represented by the general
formula (O-1) are shown below, but the compound represented by the
general formula (O-1), which can be used in the present invention,
should not be construed to be limited to the specific examples.
##STR00062## ##STR00063## ##STR00064##
[0280] The compound represented by the general formula (O-1) can be
synthesized by the method described in JP-A-2001-335776. After the
synthesis, purification is preferably carried out by column
chromatography, recrystallization, reprecipitation, or the like,
and then by sublimation purification. By the sublimation
purification, organic impurities can be separated and inorganic
salts, residual solvents, moisture, or the like can be removed
effectively.
[0281] In the organic electroluminescent element of the present
invention, the compound represented by the general formula (O-1) is
preferably included in the organic layer between the light emitting
layer and the cathode, however, it is more preferably included in
the layer on the cathode side adjacent to the light emitting
layer.
[0282] The compound represented by the general formula (O-1) is
preferably contained in the amount of 70 to 100% by mass, and more
preferably 85 to 100% by mass, based on the total mass of the
organic layer added.
[0283] The organic electroluminescent element of the present
invention preferably includes at least one layer of organic layers
between the light emitting layer and the cathode, and it is
preferable that the organic layer contain at least one of compounds
represented by the following general formula (P), from the
viewpoint of efficiency or the driving voltage of an element.
Hereinafter, the general formula (P) will be described.
##STR00065##
[0284] (In the general formula (P), R.sup.P represents an alkyl
group (preferably having 1 to 8 carbon atoms), an aryl group
(preferably having 6 to 30 carbon atoms), or a heteroaryl group
(preferably having 4 to 12 carbon atoms), which may have a
substituent selected from the above-described Substituent Group A.
nP represents an integer of 1 to 10, and in a case where there are
plural R.sup.Ps, these may be the same as or different from each
other. At least one of R.sup.Ps is a substituent represented by the
following general formulae (P-1) to (P-3).
##STR00066##
[0285] (In the general formulae (P-1) to (P-3), R.sup.P1 to
R.sup.P3 and R'.sup.P1 to R'.sup.P3 each represent an alkyl group
(preferably having 1 to 8 carbon atoms), an aryl group (preferably
having 6 to 30 carbon atoms), or a heteroaryl group (preferably
having 4 to 12 carbon atoms), which may have a substituent selected
from the above-described Substituent Group A. n.sup.P1 and n.sup.P2
represent an integer of 0 to 4, and in a case where there are a
plurality of R.sup.P1 to R.sup.P3 and R'.sup.P1 to R'.sup.P3, these
may be the same as or different from each other. L.sup.P1 to
L.sup.P3 represent any one of divalent linking groups consisting of
a single bond, an aryl ring, or a heteroaryl ring. * represents a
binding position with the anthracene ring of the general formula
(P)).
[0286] A preferred substituent other than the substituents
represented by (P-1) to (P-3) as R.sup.P is an aryl group, more
preferably any one of a phenyl group, a biphenyl group, a terphenyl
group, and a naphthyl group, and still more preferably a naphthyl
group.
[0287] R.sup.P1 to R.sup.P3 and R'.sup.P1 to R'.sup.P3 are
preferably any one of an aryl group and a heteroaryl group, more
preferably an aryl group, still more preferably any one of a phenyl
group, a biphenyl group, a terphenyl group, and a naphthyl group,
and most preferably a phenyl group.
[0288] L.sup.P1 to L.sup.P3 are preferably any one of divalent
linking groups consisting of a single bond and an aryl ring, more
preferably any one of a single bond, phenylene, biphenylene,
terphenylene, and naphthylene, still more preferably any one of a
single bond, phenylene, and naphthylene.
[0289] Specific examples of the compound represented by the general
formula (P) are shown below, but the compound represented by the
general formula (P) that can be used in the present invention
should not be construed to be limited to the specific examples.
##STR00067## ##STR00068## ##STR00069##
[0290] The compound represented by the general formula (P) can be
synthesized by the method described in WO 2003/060956 and WO
2004/080975. After the synthesis, purification is preferably
carried out by column chromatography, recrystallization,
reprecipitation, or the like, and then by sublimation purification.
By the sublimation purification, organic impurities can be
separated and inorganic salts, residual solvents, moisture, or the
like can be removed effectively.
[0291] In the organic electroluminescent element of the present
invention, the compound represented by the general formula (P) is
preferably included in the organic layer between the light emitting
layer and the cathode, and more preferably in the layer adjacent to
the cathode.
[0292] The compound represented by the general formula (P) is
preferably contained in the amount of 70 to 100% by mass, and more
preferably 85 to 100% by mass, based on the total mass of the
organic layer added.
[0293] Preferred examples of the material other than the material
used in the electron injecting layer or the electron transporting
layer in the organic electroluminescent element of the present
invention include silole compounds described in JP-A-09-194487 or
the like, phosphineoxide compounds described in JP-A-2006-73581 or
the like, nitrogen-containing aromatic 6-membered ring hetero
compounds described in JP-A-2005-276801, JP-A-2006-225320, WO
2005/085387, or the like, compounds having nitrogen-containing
aromatic 6-membered hetero structures and carbazole structures,
described in WO 2003/080760, WO 2005/085387, or the like, and
aromatic hydrocarbon compounds described in US2009/0009065, WO
2010/134350, Japanese PCT National Publication No. 2010-535806
(naphthalene compounds, anthracene compounds, triphenylene
compounds, phenanthrene compounds, pyrene compounds, fluoranthene
compounds, and the like).
Protective Layer
[0294] In the present invention, the entirety of the organic
electric element may be protected with a protective layer.
[0295] For the protective layer, the detailed description in, for
example, in Paragraph Nos. [0169] to [0170] of JP-A-2008-270736 can
also be applied to the present invention. Further, the materials
for the protective layer may be either inorganic materials or
organic materials.
Sealing Enclosure
[0296] For the organic electroluminescent element of the present
invention, the entirety of the element may be sealed with a sealing
enclosure.
[0297] For the sealing enclosure, the detailed description in
Paragraph No. [0171] of JP-A-2008-270736 can be applied to the
present invention.
Driving Method
[0298] The organic electroluminescent element of the present
invention can emit light by applying a direct current (it may
contain an alternate current component, if necessary) voltage
(typically, from 2 volts to 15 volts) or a direct current between
the anode and the cathode.
[0299] As a driving method of the organic electroluminescent
element of the present invention, driving methods described in
JP-A-2-148687, JP-A-6-301355, JP-A-5-29080, JP-A-7-134558,
JP-A-8-234685, and JP-A-8-241047, Japanese Patent No. 2784615, and
U.S. Pat. Nos. 5,828,429 and 6,023,308 can be applied.
[0300] The external quantum efficiency of the organic
electroluminescent element of the present invention is preferably
5% or more, more preferably 6% or more, and more preferably 7% or
more. As to the numerical value of the external quantum efficiency,
a maximum value of the external quantum efficiency obtained when
the organic electroluminescent element is driven at 20.degree. C.,
or a value of the external quantum efficiency in the vicinity of
from 300 to 400 cd/m obtained when the element is driven at
20.degree. C. can be employed.
[0301] The internal quantum efficiency of the organic
electroluminescent element of the present invention is preferably
30% or more, more preferably 50% or more, and still more preferably
70% or more. The internal quantum efficiency of the element is
calculated by dividing the external quantum efficiency by the light
extraction efficiency. The light extraction efficiency in usual
organic EL elements is about 20%, but by taking into consideration
the shape of a substrate, the shape of an electrode, the thickness
of an organic layer, the thickness of an inorganic layer, the
refractive index of an organic layer, the refractive index of an
inorganic layer, or the like, it is possible to increase the light
extraction efficiency to 20% or more.
Light Emitting Wavelength
[0302] The light emitting wavelength of the organic
electroluminescent element of the present invention is the same as
the maximum luminous wavelength of the material for the organic
electroluminescent element of the present invention, and is used
for the emission of the blue light in the three primary colors of
light. In the organic electroluminescent element of the present
invention, the compounds represented by the general formula (1) are
used as light emitting material to emit blue light.
Use of Organic Electroluminescent Element of the Present
Invention
[0303] The organic electroluminescent element of the present
invention can be suitably used for display elements, displays,
backlights, electrophotography, illumination light sources,
recording light sources, exposure light sources, readout light
sources, signs, billboards, interior decorations, optical
communications, and the like, and particularly preferably for
devices driven in a region of high-intensity luminescence, such as
a light emitting device, an illumination device, and a display
device.
Light Emitting Device
[0304] The light emitting device of the present invention may
include the organic electroluminescent element of the present
invention.
[0305] Next, the light emitting device of the present invention
will be described with reference to FIG. 2.
[0306] The light emitting device of the present invention is formed
by using the organic electroluminescent element.
[0307] FIG. 2 is a cross-sectional view schematically showing one
example of the light emitting device of the present invention. The
light emitting device 20 in FIG. 2 includes a transparent substrate
2 (supporting substrate), an organic electroluminescent element 10,
a sealing enclosure 16, and the like.
[0308] The organic electroluminescent element 10 is formed by
laminating on the substrate 2 an anode 3 (first electrode), an
organic layer 11, and a cathode 9 (second electrode) in this order.
In addition, a protective layer 12 is laminated on the cathode 9,
and on the protective layer 12a sealing enclosure 16 is further
provided via an adhesive layer 14. Incidentally, a part of each of
the electrodes 3 and 9, a diaphragm, an insulating layer, and the
like are omitted in FIG. 2.
[0309] Herein, a photocurable adhesive such as an epoxy resin, or a
thermosetting adhesive can be used for the adhesive layer 14, and
for example, a thermosetting adhesive sheet may also be used as the
adhesive layer 14.
[0310] The light emitting device of the present invention is not
particularly limited in its use, and it can be used as not only an
illumination device but also a display device of a television set,
a personal computer, a mobile phone, electronic paper, or the
like.
Illumination Device
[0311] The illumination device of the present invention includes
the organic electroluminescent element of the present
invention.
[0312] Next, the illumination device of the present invention will
be described with reference to FIG. 3.
[0313] FIG. 3 is a cross-sectional view schematically showing one
example of the illumination device of the present invention. The
illumination device 40 of the present invention includes, as shown
in FIG. 3, the above-described organic EL element 10 and a light
scattering member 30. More specifically, the illumination device 40
is configured such that the substrate 2 of the organic EL element
10 and the light scattering member 30 are in contact with each
other.
[0314] The light scattering member 30 is not particularly limited
as long as it can scatter light, but in FIG. 3, a member obtained
by dispersing fine particles 32 in a transparent substrate 31 is
used. Suitable examples of the transparent substrate 31 include a
glass substrate, and suitable examples of the fine particles
include transparent resin fine particles. As the glass substrate
and the transparent resin fine particles, a known product can be
used for both. In such an illumination device 40, when light
emitted from the organic electroluminescent element 10 is incident
on the light incident surface 30A of the scattering member 30, the
incident light is scattered by the light scattering member 30 and
the scattered light is output as illuminating light from the light
output surface 30B.
Display Device
[0315] The display device of the present invention includes the
organic electroluminescent element of the present invention.
[0316] The display device of the present invention can be used for,
for example, a display device of a television set, a personal
computer, a mobile phone, electronic paper, or the like.
EXAMPLES
[0317] Hereinbelow, the features of the present invention will be
described in more detail with reference to Examples and Comparative
Examples. The materials, use amounts, ratios, process details,
process sequences, and the like shown in Examples below may be
appropriately modified without departing from the spirit of the
present invention. Accordingly, the scope of the present invention
should not be construed to be limited to the specific examples
shown below.
[0318] The structural formulae of the compounds used in Examples
and Comparative Examples are summarized below.
##STR00070## ##STR00071##
[0319] The comparative compounds 1 and 4 are the compounds
described in JP-A-2006-298793, the comparative compound 2 is the
compound described in JP-A-2009-283899, and the comparative
compound 3 is the compound described in KR10-2011-0057008.
##STR00072## ##STR00073## ##STR00074## ##STR00075##
Example 1
1. Synthesis of Compounds Represented by General Formula (1)
[0320] The compounds represented by the general formula (1) can be
synthesized by a combination of known reactions, including the
methods descried in JP-A-2009-283899, and JP-A-2006-298793. The
following describes representative examples of specific synthesis
procedures for the compounds represented by the general formula
(1).
Synthesis of Compound 1
##STR00076##
[0321] Synthesis of Compound 1a
[0322] Bromine (26 ml) was dropped onto a dichloromethane solution
(500 ml) of 1,2,3,6,7,8-hexahydropyrene (ALDRICH; 50 g) at room
temperature, and the mixture was stirred for 4 hours. The
precipitated crystals were filtered, and washed with ethanol and
hexane to obtain compound 1a (39 g).
Synthesis of Compound 1b
[0323]
[1,1'-bis(Diphenylphosphino)ferrocene]palladium(II)dichloride
(PdCl.sub.2(dppf); 0.8 g) was added to a toluene solution (60 ml)
of compound 1a (5 g), bispinacoldiborane (17.4 g), and potassium
acetate (4 g), and the mixture was stirred under nitrogen
atmosphere at 80.degree. C. for 8 hours. The reaction liquid was
Celite filtered, and the filtrate was concentrated under reduced
pressure. Ethanol was added to the concentrate residue, and
filtered to obtain compound 1b (5.3 g).
Synthesis of Compound 1c
[0324] Compound 1b (1 g), 4-bromotriphenylamine (Tokyo Kasei; 1.55
g), 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (SPhos; 0.21
g), potassium phosphate (2.3 g),
tris(dibenzylideneacetone)dipalladium (Pd.sub.2(dba).sub.3; 0.12
g), and toluene/water=2/1 (30 ml) were mixed, and stirred under
nitrogen atmosphere at 100.degree. C. for 3 hours. After bringing
the reaction liquid back to room temperature, toluene and deionized
water were added, and the organic layer was extracted. The organic
layer was dried over sodium sulfate, concentrated under reduced
pressure, and purified by silica gel column chromatography to
obtain compound 1c (1.27 g).
Synthesis of Compound 1
[0325] 10% Pd/C (31 mg) was stirred in a triglyme solution (100 ml)
of compound 1c (1 g) under nitrogen atmosphere at 100.degree. C.
for 5 hours. After bringing the reaction liquid back to room
temperature, the solution was Celite filtered. Then, toluene and
deionized water were added, and the organic layer was extracted.
The organic layer was dried over sodium sulfate, and concentrated
under reduced pressure. The concentrate residue was recrystallized
from ethanol/toluene to obtain compound 1 (0.77 g). The compound
was identified by elemental analysis, NMR, and MASS spectrometry.
.sup.1H-NMR (CDCl.sub.3)
[0326] .delta.(ppm)=:7.02-7.1 (4H, dd), 7.2-7.38 (20H, m), 7.58
(4H, d), 8.0 (2H, dd), 8.09 (2H, s), 8.21 (2H, d), 8.33 (2H, d)
[0327] Compounds 2 to 36 used in Examples were also synthesized by
using methods similar to that used for compound 1. Comparative
Compounds 1 to 4 were synthesized by referring to known documents
describing the compounds.
2. Evaluation of Physical Properties of Materials
(a) Evaluation of Chromaticity
[0328] The following host material H-5 and the respective light
emitting materials shown in Table 1 below were deposited on a
quartz glass substrate (25 mm.times.25 mm.times.0.7 mm) by a vacuum
deposition method at a mass ratio (95:5) to form a thin film having
a film thickness of 50 nm. The luminous spectrum of the emitted
light from the thin film irradiated with 350-nm UV rays was
measured using a fluorescence spectrophotometer (FP-6300,
manufactured by JASCO Corporation) to determine the chromaticity
(x, y). Based on the y value at this time, the chromaticity was
evaluated according to the following three criteria. The results
are shown in Table 1 below.
Good: 0.04.ltoreq.y<0.09 Acceptable: 0.03.ltoreq.y<0.04,
0.09<y.ltoreq.0.12 Poor: y<0.03, 0.12<y
##STR00077##
TABLE-US-00001 TABLE 1 Light emitting material Chromaticity Note
Compound 1 Good Present invention Compound 3 Good Present invention
Compound 4 Good Present invention Compound 6 Good Present invention
Compound 7 Good Present invention Compound 8 Acceptable Present
invention Compound 9 Good Present invention Compound 11 Good
Present invention Compound 12 Good Present invention Compound 14
Good Present invention Compound 21 Acceptable Present invention
Comparative compound 1 Poor Comparative Example Comparative
compound 2 Poor Comparative Example Comparative compound 3 Poor
Comparative Example Comparative compound 4 Poor Comparative
Example
Example 2
Production and Evaluation of Organic Electroluminescent Element
[0329] The materials used for the production of the organic
electroluminescent element were all purified by sublimation, and
the purity (absorption intensity area ratio at 254 nm) was
confirmed to be 99.9% or higher by high-performance liquid
chromatography (Tosoh TSK gel ODS-100Z).
[0330] A 0.5 mm-thick and 2.5 cm square glass substrate (product of
Geomatec Co., Ltd., surface resistance: 10.OMEGA./quadrature)
having an ITO film thereon was put in a cleaning container. After
ultrasonic cleaning in 2-propanol, the glass substrate was
subjected to a UV-ozone treatment for 30 minutes. The following
organic compound layers were deposited sequentially on the
transparent anode (ITO film) by a vacuum deposition method.
[0331] Note that the deposition rate in the Examples and
Comparative Examples below is 0.1 nm/sec unless otherwise
specifically indicated. The deposition rate was measured using a
quartz oscillator. In addition, the thicknesses of the respective
layers below were measured using the quartz oscillator.
[0332] First layer: HAT-CN: thickness 10 nm
[0333] Second layer: HT-2: thickness 30 nm
[0334] Third layer: H-1 and light emitting material (mass
ratio=93:7) shown in Table 2: thickness 30 nm
[0335] Fourth layer: ET-1: thickness 30 nm
[0336] 1 nm of lithium fluoride and 100 nm of metal aluminum were
deposited in this order thereon to form a cathode. At this time, a
patterned mask (mask having a light emitting area of 2 mm.times.2
mm) was provided on the layer of lithium fluoride to deposit the
metal aluminum.
[0337] The obtained laminate was put in a glove box purged with a
nitrogen gas without bringing it into contact with the atmosphere,
and then sealed with a sealing can made of glass and an ultraviolet
curing adhesive (XNR5516HV, manufactured by Nagase Chemical Co.,
Ltd.) to obtain organic electroluminescent elements 1-1 to 1-11,
and comparative organic electroluminescent elements 1-1 to 1-4, in
square shapes having a light emitting area of 2 mm.times.2 mm. In
all of the elements, light emitting derived from the light emitting
materials was observed. For the respective organic
electroluminescent elements thus obtained, the following tests were
carried out. The results of evaluations for external quantum
efficiency, chromaticity, and chromaticity change after
deterioration by driving are presented in Table 2 below.
(a) External Quantum Efficiency
[0338] A direct current voltage was applied to each element by
using a source measure unit 2400 (Keithley Instruments Inc.) to
allow the organic electroluminescent element to emit light. The
luminance was measured with a luminance meter (BM-8, manufactured
by Topcon Corporation). The emission spectrum and the light
emitting wavelength were measured with a spectrum analyzer PMA-11
(Hamamatsu Photonics K. K.). Based on these values, the external
quantum efficiency (.eta.) at a luminance in the vicinity of 1,000
cd/m.sup.2 was calculated by using a luminance conversion method,
and shown as a relative value, taking the value of the comparative
element 1-1 (organic electroluminescent element using the
comparative compound 1) as 1.0. Larger numeral values are
preferable, because larger values indicate better efficiency.
(b) Chromaticity
[0339] The chromaticity (x, y) was determined from the luminous
spectrum of the light emitted at a luminance of 1,000 cd/m.sup.2
after a direct current voltage was applied to each organic
electroluminescent element. From the y values at the time, the
chromaticity was evaluated according to the following three
criteria.
Good: 0.04.ltoreq.y.ltoreq.0.09 Acceptable: 0.03.ltoreq.y<0.04,
0.09<y.ltoreq.0.12 Poor: y<0.03, 0.12<y (c) Chromaticity
after Deterioration by Driving
[0340] DC voltage was continuously applied to cause each organic
electroluminescent element to emit light at a luminance of 1,000
cd/m.sup.2, and the chromaticity (x', y') after the luminance
decreased to 500 cd/m was measured from the emission spectrum.
Chromaticity change after deterioration by driving was evaluated
according to the following three criteria, using changes in y
values .DELTA.y (=|y'-.DELTA.y|) before and after the deterioration
by driving.
Good: .DELTA.y.ltoreq.0.01 Acceptable:
0.01<.DELTA.y.ltoreq.0.02
Poor: 0.02<.DELTA.y
TABLE-US-00002 [0341] TABLE 2 Relative Chromaticity Light external
after emitting quantum deterioration Element No. material
efficiency Chromaticity by driving Note Element 1-1 Compound 1 1.1
Good Good Present Invention Element 1-2 Compound 3 1.2 Good Good
Present Invention Element 1-3 Compound 4 1.1 Good Good Present
Invention Element 1-4 Compound 6 1.2 Good Good Present Invention
Element 1-5 Compound 7 1.2 Good Good Present Invention Element 1-6
Compound 8 1.2 Acceptable Good Present Invention Element 1-7
Compound 9 1.3 Good Good Present Invention Element 1-8 Compound 11
1.3 Good Good Present Invention Element 1-9 Compound 12 1.3 Good
Good Present Invention Element 1-10 Compound 14 1.2 Good Good
Present Invention Element 1-11 Compound 21 1.1 Acceptable Good
Present Invention Comparative Comparative 1.0 Poor Acceptable
Comparative element 1-1 compound 1 Example Comparative Comparative
Emission from Poor Acceptable Comparative element 1-2 compound 2
host material Example Comparative Comparative 0.2 Poor Poor
Comparative element 1-3 compound 3 Example Comparative Comparative
0.8 Poor Poor Comparative element 1-4 compound 4 Example
Example 3
[0342] Organic electroluminescent elements 2-1 to 2-11 and
comparative elements 2-1 to 2-4 were produced in the same manner as
in Example 2, except that the layer configurations were changed as
follows. Evaluations were carried out in the same manner as in
Example 2. The results are presented in Table 3 below. Note that
the external quantum efficiency shown in Table 3 below is shown as
a relative value, taking the value of the comparative element 2-1
(organic electroluminescent element using comparative compound 1)
as 1.0.
First layer: HT-4: thickness 50 nm Second layer: HT-3: thickness 45
nm Third layer: H-2 and light emitting material (mass ratio=95:5)
shown in Table 3: thickness 25 nm Fourth layer: ET-5: thickness 5
nm Fifth layer: ET-3: thickness 20 nm
TABLE-US-00003 TABLE 3 Relative Chromaticity Light external after
emitting quantum deterioration Element No. material efficiency
Chromaticity by driving Note Element 2-1 Compound 1 1.1 Good Good
Present Invention Element 2-2 Compound 3 1.2 Good Good Present
Invention Element 2-3 Compound 4 1.1 Good Good Present Invention
Element 2-4 Compound 6 1.2 Good Good Present Invention Element 2-5
Compound 7 1.2 Good Good Present Invention Element 2-6 Compound 8
1.2 Acceptable Good Present Invention Element 2-7 Compound 9 1.3
Good Good Present Invention Element 2-8 Compound 11 1.3 Good Good
Present Invention Element 2-9 Compound 12 1.3 Good Good Present
Invention Element 2-10 Compound 14 1.2 Good Good Present Invention
Element 2-11 Compound 21 1.1 Acceptable Good Present Invention
Comparative Comparative 1.0 Poor Acceptable Comparative element 2-1
compound 1 Example Comparative Comparative Emission from Poor
Acceptable Comparative element 2-2 compound 2 host material Example
Comparative Comparative 0.3 Poor Poor Comparative element 2-3
compound 3 Example Comparative Comparative 0.7 Poor Poor
Comparative element 2-4 compound 4 Example
Example 4
[0343] Organic electroluminescent elements 3-1 to 3-11 and
comparative elements 3-1 to 3-4 were produced in the same manner as
in Example 2, except that the layer configurations were changed as
follows. Evaluations were carried out in the same manner as in
Example 2. The results are presented in Table 4 below. Note that
the external quantum efficiency shown in Table 4 below is shown as
a relative value, taking the value of the comparative element 3-1
(organic electroluminescent element using comparative compound 1)
as 1.0.
First layer: HAT-CN: thickness 10 nm Second layer: HT-2: thickness
30 nm Third layer: H-1 and light emitting material (mass
ratio=95:5) shown in Table 4: thickness 30 nm Fourth layer: ET-4:
thickness 30 nm
TABLE-US-00004 TABLE 4 Relative Chromaticity Light external after
emitting quantum deterioration Element No. material efficiency
Chromaticity by driving Note Element 3-1 Compound 1 0.9 Good Good
Present Invention Element 3-2 Compound 3 1.1 Good Good Present
Invention Element 3-3 Compound 4 0.9 Good Good Present Invention
Element 3-4 Compound 6 1.1 Good Good Present Invention Element 3-5
Compound 7 1.1 Good Good Present Invention Element 3-6 Compound 8
1.1 Acceptable Good Present Invention Element 3-7 Compound 9 1.2
Good Good Present Invention Element 3-8 Compound 11 1.2 Good Good
Present Invention Element 3-9 Compound 12 1.2 Good Good Present
Invention Element 3-10 Compound 14 1.1 Good Good Present Invention
Element 3-11 Compound 21 0.9 Acceptable Good Present Invention
Comparative Comparative 1.0 Poor Acceptable Comparative element 3-1
compound 1 Example Comparative Comparative Emission from Poor
Acceptable Comparative element 3-2 compound 2 host material Example
Comparative Comparative 0.2 Poor Poor Comparative element 3-3
compound 3 Example Comparative Comparative 0.7 Poor Poor
Comparative element 3-4 compound 4 Example
Example 5
[0344] Organic electroluminescent elements were produced in the
same manner as in Example 2, except that the layer configurations
were changed as follows. Evaluations were carried out in the same
manner as in Example 2. The results are presented in Table 5 below.
Note that the external quantum efficiency shown in Table 5 below is
shown as a relative value, taking the value of the comparative
element 4-1 (organic electroluminescent element using comparative
compound 1) as 1.0.
First layer: HAT-CN: thickness 10 nm Second layer: HT-1: thickness
30 nm Third layer: H-3 and light emitting material (mass
ratio=93:7) shown in Table 5: thickness 30 nm Fourth layer: ET-4:
thickness 30 nm
TABLE-US-00005 TABLE 5 Relative Chromaticity Light external after
emitting quantum deterioration Element No. material efficiency
Chromaticity by driving Note Element 4-1 Compound 1 0.9 Good Good
Present Invention Element 4-2 Compound 3 1.1 Good Good Present
Invention Element 4-3 Compound 4 1.0 Good Good Present Invention
Element 4-4 Compound 6 1.1 Good Good Present Invention Element 4-5
Compound 7 1.1 Good Good Present Invention Element 4-6 Compound 8
1.1 Acceptable Good Present Invention Element 4-7 Compound 9 1.2
Good Good Present Invention Element 4-8 Compound 11 1.1 Good Good
Present Invention Element 4-9 Compound 12 1.2 Good Good Present
Invention Element 4-10 Compound 14 1.1 Good Good Present Invention
Element 4-11 Compound 21 0.9 Acceptable Good Present Invention
Comparative Comparative 1.0 Poor Acceptable Comparative element 4-1
compound 1 Example Comparative Comparative 0.2 Poor Acceptable
Comparative element 4-2 compound 2 Example Comparative Comparative
0.4 Poor Poor Comparative element 4-3 compound 3 Example
Comparative Comparative 0.9 Poor Poor Comparative element 4-4
compound 4 Example
Example 6
[0345] Organic electroluminescent elements were produced in the
same manner as in Example 2, except that the layer configurations
were changed as follows. Evaluations were carried out in the same
manner as in Example 2. The results are presented in Table 6 below.
Note that the external quantum efficiency shown in Table 6 below is
shown as a relative value, taking the value of the comparative
element 5-1 (organic electroluminescent element using comparative
compound 1) as 1.0.
First layer: HAT-CN: thickness 10 nm Second layer: HT-2: thickness
30 nm Third layer: H-4 and light emitting material (mass
ratio=93:7) shown in Table 6: thickness 30 nm Fourth layer: ET-2:
thickness 30 nm
TABLE-US-00006 TABLE 6 Relative Chromaticity Light external after
emitting quantum deterioration Element No. material efficiency
Chromaticity by driving Note Element 5-1 Compound 1 1.0 Good Good
Present Invention Element 5-2 Compound 3 1.1 Good Good Present
Invention Element 5-3 Compound 4 0.9 Good Good Present Invention
Element 5-4 Compound 6 1.1 Good Good Present Invention Element 5-5
Compound 7 1.1 Good Good Present Invention Element 5-6 Compound 8
1.1 Acceptable Good Present Invention Element 5-7 Compound 9 1.3
Good Good Present Invention Element 5-8 Compound 11 1.2 Good Good
Present Invention Element 5-9 Compound 12 1.2 Good Good Present
Invention Element 5-10 Compound 14 1.2 Good Good Present Invention
Element 5-11 Compound 21 1.0 Acceptable Good Present Invention
Comparative Comparative 1.0 Poor Acceptable Comparative element 5-1
compound 1 Example Comparative Comparative Emission from Poor
Acceptable Comparative element 5-2 compound 2 host material Example
Comparative Comparative 0.1 Poor Poor Comparative element 5-3
compound 3 Example Comparative Comparative 0.8 Poor Poor
Comparative element 5-4 compound 4 Example
Example 7
Evaluation of Organic Electroluminescent Element (Coating)
Preparation of Light Emitting Layer-Forming Coating Liquids 1 to 6
and Comparative Light Emitting Layer-Forming Coating Liquids 1 and
2
[0346] Compound 5 as a light emitting material (0.1% by mass), a
host material PH-1 having the following structure (0.9% by mass),
and methyl ethyl ketone (98.99% by mass) were mixed to obtain a
light emitting layer-forming coating liquid 1.
[0347] Light emitting layer-forming coating liquids 2 and 3 were
prepared in the same manner as for the light emitting layer-forming
coating liquid 1, except that the compound 5 in the light emitting
layer-forming coating liquid 1 was changed to compounds 11 and 17.
For comparison, comparative light emitting layer-forming coating
liquid 1 was prepared in the same manner as for the light emitting
layer-forming coating liquid 1, except that the compound 5 in the
light emitting layer-forming coating liquid 1 was changed to
comparative compound 2.
[0348] Further, light emitting layer-forming coating liquids 4 to
6, and a comparative light emitting layer-forming coating liquid 2
were prepared in the same manner as for the light emitting
layer-forming coating liquids 1 to 3 and the comparative light
emitting layer-forming coating liquid 1, except that the host
material PH-1 in the light emitting layer-forming coating liquids 1
to 3 and in the comparative light emitting layer-forming coating
liquid 1 was changed to a host material H-2.
##STR00078##
Preparation of Organic Electroluminescent Element P1
[0349] ITO was deposited on a glass substrate (25 mm.times.25
mm.times.0.7 mm) to give a thickness of 150 nm, thereby forming a
film. The film was taken as a transparent supporting substrate.
This transparent supporting substrate was etched and washed.
[0350] On this ITO glass substrate, 2 parts by mass of PTPDES-2
represented by the following structural formula (manufactured by
Chemipro Kasei Kaisha, Ltd., Tg=205.degree. C.) was dissolved in 98
parts by mass of cyclohexanone for the Electronics Industry
(manufactured by Kanto Chemical Co., Inc.) and spin-coated (2,000
rpm, 20 seconds) to give a thickness of about 40 nm, and then dried
at 120.degree. C. for 30 minutes and subjected to an annealing
treatment at 160.degree. C. for 10 minutes to form a hole injecting
layer.
##STR00079##
[0351] The coating liquid 1 for forming a light emitting layer was
spin-coated on a hole injecting layer (1,300 rpm, 30 seconds) to
give a thickness of about 40 nm, thereby obtaining a light emitting
layer.
[0352] Subsequently, BAlq
(bis-(2-methyl-8-quinolato)-4-(phenylphenolate)-aluminum (III))
represented by the following structural formula was formed as an
electron transporting layer on a light emitting layer to give a
thickness of 40 nm by a vacuum deposition method.
##STR00080##
[0353] Lithium fluoride (LiF) was formed as an electron injecting
layer on an electron transporting layer to give a thickness of 1 nm
by a vacuum deposition method. Metal aluminum was further deposited
to 70 nm thereon to give a cathode.
[0354] The laminate thus prepared was put into a globe box purged
with an argon gas, and then sealed with a sealing can made of
stainless steel and an ultraviolet curing adhesive (XNR5516HV,
manufactured by Nagase Chemical Co., Ltd.) to obtain an organic
electroluminescent element P1.
Production of Organic Electroluminescent Elements P2 to P8
[0355] Organic electroluminescent elements P2 to P6 were produced
in the same manner as for the organic electroluminescent element
P1, except that the light emitting layer-forming coating liquid 1
was changed to the light emitting layer-forming coating liquids 2
to 6 in production of the organic electroluminescent element
P1.
[0356] For comparison, organic electroluminescent elements P7 and
P8 were produced in the same manner as for the organic
electroluminescent element P1, except that the light emitting
layer-forming coating liquid 1 was changed to the comparative light
emitting layer-forming coating liquids 1 and 2 in production of the
organic electroluminescent element P1.
EVALUATION
[0357] Evaluation was carried out for the organic
electroluminescent elements P1 to P8 in the same manner as in
Example 2. The results are shown in Table 7 below. Note that the
external quantum efficiency in Table 7 below is shown as a relative
value, taking the values of the organic electroluminescent elements
P7 and P8 that use the comparative compound 2 as 1.0.
TABLE-US-00007 TABLE 7 Organic Relative Chromaticity electro- Light
external change after luminescent emitting Host quantum
deterioration element material material efficiency Chromaticity by
driving Note P1 Compound 5 PH-1 3.9 Good Good Present Invention P2
Compound 11 PH-1 5.3 Good Good Present Invention P3 Compound 17
PH-1 5.1 Good Good Present Invention P7 Comparative PH-1 1.0 Poor
Acceptable Comparative compound 2 Example P4 Compound 5 H-2 3.8
Good Good Present Invention P5 Compound 11 H-2 5.4 Good Good
Present Invention P6 Compound 17 H-2 5.1 Good Good Present
Invention P8 Comparative H-2 1.0 Poor Acceptable Comparative
compound 2 Example
[0358] It was found from the results presented in these tables, the
organic electroluminescent elements using the compounds of the
present invention as light emitting material had sufficient
luminous efficiency, and excellent chromaticity. In a preferred
aspect of the present invention, chromaticity change after
deterioration by driving was excellent.
[0359] On the other hand, the comparative elements using the
comparative compound 1 described in JP-A-2006-298793 was found to
be inferior in terms of chromaticity, and chromaticity change after
deterioration by driving.
* * * * *