U.S. patent application number 13/494071 was filed with the patent office on 2012-10-04 for polymeric material and polymeric luminescent element.
This patent application is currently assigned to SUMITOMO CHEMICAL COMPANY, LIMITED. Invention is credited to Tomoya NAKATANI, Takeshi YAMADA.
Application Number | 20120248423 13/494071 |
Document ID | / |
Family ID | 37570462 |
Filed Date | 2012-10-04 |
United States Patent
Application |
20120248423 |
Kind Code |
A1 |
NAKATANI; Tomoya ; et
al. |
October 4, 2012 |
POLYMERIC MATERIAL AND POLYMERIC LUMINESCENT ELEMENT
Abstract
A luminescent or charge-transporting polymer which has in the
backbone optionally substituted fluorenediyl groups as repeating
units and further has a functional side chain comprising at least
one functional group selected from the group consisting of a
hole-injection/transporting group containing one or more
heteroatoms other than nitrogen or two or more nitrogen atoms, an
electron-injection/transporting group containing one or more
heteroatoms other than nitrogen or two or more nitrogen atoms, and
a luminescent group comprising a fused aromatic hydrocarbon or
heterocycle, characterized in that the functional group is directly
bonded to the saturated carbon atom of any of the fluorenediyl
groups or is bonded to any of the fluorenediyl groups through
--R.sub.k--X-- (R.sub.k represents alkylene and X represents a
direct bond or connecting group) at the X.
Inventors: |
NAKATANI; Tomoya; (Tsukuba,
JP) ; YAMADA; Takeshi; (Tsukuba, JP) |
Assignee: |
SUMITOMO CHEMICAL COMPANY,
LIMITED
Tokyo
JP
|
Family ID: |
37570462 |
Appl. No.: |
13/494071 |
Filed: |
June 12, 2012 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11993703 |
Dec 21, 2007 |
8222632 |
|
|
PCT/JP2006/312404 |
Jun 21, 2006 |
|
|
|
13494071 |
|
|
|
|
Current U.S.
Class: |
257/40 ;
252/301.35; 252/500; 257/E27.119; 257/E51.018; 257/E51.026; 438/99;
526/280 |
Current CPC
Class: |
C09K 2211/1088 20130101;
C09K 2211/1037 20130101; C09K 2211/104 20130101; C09K 11/06
20130101; H01L 51/0062 20130101; C09K 2211/1029 20130101; H01L
51/0081 20130101; C09K 2211/1007 20130101; C09K 2211/1059 20130101;
C09K 2211/185 20130101; C09K 2211/1033 20130101; H01L 51/0059
20130101; C09K 2211/1092 20130101; H01L 51/0052 20130101; C09K
2211/1014 20130101; C08G 61/12 20130101; H01L 51/5048 20130101;
H01L 51/0036 20130101; C09K 2211/1044 20130101; C09K 2211/1096
20130101; H01L 51/5012 20130101; H01L 51/0078 20130101; H05B 33/14
20130101; H01L 51/0094 20130101; H01L 51/0039 20130101; C09K
2211/1048 20130101; C09K 2211/1011 20130101; H01L 51/0077 20130101;
C09K 2211/1051 20130101 |
Class at
Publication: |
257/40 ; 438/99;
526/280; 252/500; 252/301.35; 257/E51.026; 257/E51.018;
257/E27.119 |
International
Class: |
C08G 73/02 20060101
C08G073/02; C09K 11/06 20060101 C09K011/06; H01L 51/56 20060101
H01L051/56; H01B 1/12 20060101 H01B001/12; H01L 51/54 20060101
H01L051/54; H01L 27/32 20060101 H01L027/32 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 22, 2005 |
JP |
2005-182275 |
Claims
1. A solution characterized by comprising at least one kind of
polymer compound having a fluorenediyl group that may have a
substituent as a repeat unit in a main chain and a functional side
chain containing at least one functional group selected from the
group consisting of a hole injection/transport group containing at
least one hetero atom other than a nitrogen atom or at least two
nitrogen atoms, an electron injection/transport group containing at
least one hetero atom other than a nitrogen atom or at least two
nitrogen atoms, and a light emitting group containing a condensed
polycyclic aromatic hydrocarbon or a heterocyclic ring,
characterized in that the functional group is directly bonded to a
saturated carbon of the fluorenediyl group or bonded to the
fluorenediyl group via --R.sub.k--X-- (R.sub.k represents an
alkylene group and X represents a direct bond or bonding group) at
X.
2. A solution characterized by comprising a composition comprising
at least one kind of material selected from the group consisting of
a hole transport material, an electron transport material and a
light-emitting material, and at least one kind of polymer compound
having a fluorenediyl group that may have a substituent as a repeat
unit in a main chain and a functional side chain containing at
least one functional group selected from the group consisting of a
hole injection/transport group containing at least one hetero atom
other than a nitrogen atom or at least two nitrogen atoms, an
electron injection/transport group containing at least one hetero
atom other than a nitrogen atom or at least two nitrogen atoms, and
a light emitting group containing a condensed polycyclic aromatic
hydrocarbon or a heterocyclic ring, characterized in that the
functional group is directly bonded to a saturated carbon of the
fluorenediyl group or bonded to the fluorenediyl group via
--R.sub.k--X-- (R.sub.k represents an alkylene group and X
represents a direct bond or bonding group) at X.
3. The solution according to claim 1, characterized by comprising
at least two kinds of organic solvents.
4. The solution according to claim 1, wherein a viscosity thereof
is 1 to 20 mPas at 25.degree. C.
5. A method of forming a thin film according to claim 1
characterized by using an inkjet method.
6. A polymer light-emitting device having an organic layer
containing a polymer compound having a fluorenediyl group that may
have a substituent as a repeat unit in a main chain and a
functional side chain containing at least one functional group
selected from the group consisting of a hole injection/transport
group containing at least one hetero atom other than a nitrogen
atom or at least two nitrogen atoms, an electron
injection/transport group containing at least one hetero atom other
than a nitrogen atom or at least two nitrogen atoms, and a light
emitting group containing a condensed polycyclic aromatic
hydrocarbon or a heterocyclic ring, characterized in that the
functional group is directly bonded to a saturated carbon of the
fluorenediyl group or bonded to the fluorenediyl group via
--R.sub.k--X-- (R.sub.k represents an alkylene group and X
represents a direct bond or bonding group) at X or a composition
between electrodes consisting of an anode and a cathode, the
composition characterized by comprising at least one kind of
material selected from the group consisting of a hole transport
material, an electron transport material and a light-emitting
material, and at least one kind of polymer compound having a
fluorenediyl group that may have a substituent as a repeat unit in
a main chain and a functional side chain containing at least one
functional group selected from the group consisting of a hole
injection/transport group containing at least one hetero atom other
than a nitrogen atom or at least two nitrogen atoms, an electron
injection/transport group containing at least one hetero atom other
than a nitrogen atom or at least two nitrogen atoms, and a light
emitting group containing a condensed polycyclic aromatic
hydrocarbon or a heterocyclic ring, characterized in that the
functional group of the composition is directly bonded to a
saturated carbon of the fluorenediyl group or bonded to the
fluorenediyl group via --R.sub.k--X-- (R.sub.k represents an
alkylene group and X represents a direct bond or bonding group) at
X.
7. The polymer light-emitting device according to claim 6, wherein
the organic layer is a light-emitting layer.
8. The polymer light-emitting device according to claim 7, wherein
the light-emitting layer further contains a hole transport
material, an electron transport material or a light-emitting
material.
9. The polymer light-emitting device according to claim 6,
comprising a light-emitting layer and a charge transport layer
between electrodes consisting of an anode and a cathode, wherein
the charge transport layer contains a polymer compound having a
fluorenediyl group that may have a substituent as a repeat unit in
a main chain and a functional side chain containing at least one
functional group selected from the group consisting of a hole
injection/transport group containing at least one hetero atom other
than a nitrogen atom or at least two nitrogen atoms, an electron
injection/transport group containing at least one hetero atom other
than a nitrogen atom or at least two nitrogen atoms, and a light
emitting group containing a condensed polycyclic aromatic
hydrocarbon or a heterocyclic ring, characterized in that the
functional group is directly bonded to a saturated carbon of the
fluorenediyl group or bonded to the fluorenediyl group via
--R.sub.k--X-- (R.sub.k represents an alkylene group and X
represents a direct bond or bonding group) at X or a composition
characterized by comprising at least one kind of material selected
from the group consisting of a hole transport material, an electron
transport material and a light-emitting material, and at least one
kind of polymer compound having a fluorenediyl group that may have
a substituent as a repeat unit in a main chain and a functional
side chain containing at least one functional group selected from
the group consisting of a hole injection/transport group containing
at least one hetero atom other than a nitrogen atom or at least two
nitrogen atoms, an electron injection/transport group containing at
least one hetero atom other than a nitrogen atom or at least two
nitrogen atoms, and a light emitting group containing a condensed
polycyclic aromatic hydrocarbon or a heterocyclic ring,
characterized in that the functional group of the composition is
directly bonded to a saturated carbon of the fluorenediyl group or
bonded to the fluorenediyl group via --R.sub.k--X-- (R.sub.k
represents an alkylene group and X represents a direct bond or
bonding group) at X.
10. The polymer light-emitting device according to claim 6,
comprising a light-emitting layer and a charge transport layer
between electrodes consisting of an anode and a cathode, and a
charge injection layer between the charge transport layer and the
electrodes, wherein the charge injection layer contains a polymer
compound having a fluorenediyl group that may have a substituent as
a repeat unit in a main chain and a functional side chain
containing at least one functional group selected from the group
consisting of a hole injection/transport group containing at least
one hetero atom other than a nitrogen atom or at least two nitrogen
atoms, an electron injection/transport group containing at least
one hetero atom other than a nitrogen atom or at least two nitrogen
atoms, and a light emitting group containing a condensed polycyclic
aromatic hydrocarbon or a heterocyclic ring, characterized in that
the functional group is directly bonded to a saturated carbon of
the fluorenediyl group or bonded to the fluorenediyl group via
--R.sub.k--X-- (R.sub.k represents an alkylene group and X
represents a direct bond or bonding group) at X or a composition
characterized by comprising at least one kind of material selected
from the group consisting of a hole transport material, an electron
transport material and a light-emitting material, and at least one
kind of polymer compound having a fluorenediyl group that may have
a substituent as a repeat unit in a main chain and a functional
side chain containing at least one functional group selected from
the group consisting of a hole injection/transport group containing
at least one hetero atom other than a nitrogen atom or at least two
nitrogen atoms, an electron injection/transport group containing at
least one hetero atom other than a nitrogen atom or at least two
nitrogen atoms, and a light emitting group containing a condensed
polycyclic aromatic hydrocarbon or a heterocyclic ring,
characterized in that the functional group of the composition is
directly bonded to a saturated carbon of the fluorenediyl group or
bonded to the fluorenediyl group via --R.sub.k--X-- (R.sub.k
represents an alkylene group and X represents a direct bond or
bonding group) at X.
11. A planar light source characterized by comprising a polymer
light-emitting device according to claim 6.
12. A segment display device characterized by comprising a polymer
light-emitting device according to claim 6.
13. A dot matrix display device characterized by comprising a
polymer light-emitting device according to claim 6.
14. A liquid crystal display device characterized by comprising a
polymer light-emitting device according to claim 6 as a backlight.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a divisional of application Ser. No. 11/993,703
filed Dec. 21, 2007, which is a U.S. National Phase Application
under 35 U.S.C. .sctn.371 of International Patent Application No.
PCT/JP2006/312404 filed Jun. 21, 2006, which claims the benefit of
Japanese Application No. 2005-182275 filed Jun. 22, 2005, the
disclosures of all of which are incorporated by reference
herein.
TECHNICAL FIELD
[0002] The present invention relates to a polymer compound and a
polymer light-emitting device using the same.
BACKGROUND ART
[0003] A high-polymer weight light-emitting material and charge
transport material are soluble in a solvent and capable of forming
an organic layer in a light-emitting device by a coating method.
Therefore, various types of materials have been investigated. For
example, a polymer compound having the following structure, in
which two benzene rings (see, e.g., Non-Patent Document 1 and
Patent Document 1) are condensed with a cyclopentadiene ring, is
known.
##STR00001##
[0004] As another example, a polymer compound having a functional
substituent such as hole injection/transport group, an electron
injection/transport group or a light-emitting group in a conjugated
main chain and side chain (see, e.g., Patent Documents 2 and 3 and
Non-Patent Documents 2 and 3).
[0005] Patent Document 1: International Publication WO99/54385
pamphlet,
[0006] Patent Document 2: JP-A-2004-277568
[0007] Patent Document 3: WO2001-62822
[0008] Non-Patent Document 1: Advanced Materials, Vol. 9, No. 10
(1997), p. 798
[0009] Non-Patent Document 2: Advanced Materials, 2002, 14(11),
809-811
[0010] Non-Patent Document 3: J. Polymer Science, Part A; 2005,
43(3), 859-869
DISCLOSURE OF THE INVENTION
Problem to be Solved by the Invention
[0011] When a polymer compound is used as a light-emitting material
for a light-emitting device, in order to obtain high light emission
properties, the polymer compound must have good injectability and
transportability of positive charge (holes) and negative charge
(electrons) and have high light emission efficiency. However, it
may not be said that conventional polymer compounds mentioned above
have sufficient properties. In the circumstances, it has been
desired to develop a polymer compound having high charge
injectability/transportability and high light emission
efficiency.
Means for Solving the Problem
[0012] The present invention therefore provides a light emitting or
charge transport polymer compound having a fluorenediyl group that
may have a substituent as a repeat unit in the main chain and a
functional side chain containing at least one functional group
selected from the group consisting of a hole injection/transport
group containing at least one hetero atom other than a nitrogen
atom or at least two nitrogen atoms, an electron
injection/transport group containing at least one hetero atom other
than a nitrogen atom or at least two nitrogen atoms, and a light
emitting group containing a condensed polycyclic aromatic
hydrocarbon or a heterocyclic ring,
[0013] characterized in that the functional group is directly
bonded to a saturated carbon of the fluorenediyl group or bonded to
the fluorenediyl group via --R.sub.k--X-- (R.sub.k represents an
alkylene group and X represents a direct bond or bonding group) at
X.
Advantages of the Invention
[0014] The polymer compound of the present invention has effects
such as high charge injectability and transportability and high
light emission efficiency. When a side chain has a hole
injection/transport group, the energy of the highest occupied
molecular orbital (HOMO) increases, with the result that hole
injectability and hole transportability improve, increasing light
emission efficiency. When a side chain has an electron
injection/transport group, the energy of the lowest unoccupied
orbital (LUMO) decreases, with the result that electron
injectability and electron transportability improve, increasing
light emission efficiency. When a side chain has a light-emitting
group, it is expected that the light emission efficiency increases
or light having a different wavelength from that of the main chain
is emitted.
[0015] When a polymer compound whose main chain has electron
transportability and side chain has a hole injection/transport
group, a new function can be added without inhibiting the electron
transportability of the main chain and the transportability of
electrons and holes can be controlled.
[0016] When a polymer compound whose main chain has electron
transportability and side chain has a light-emitting group, light
having a different wavelength from that of the main chain can be
emitted.
Furthermore, when a light-emitting group having high efficiency is
used, the light emission efficiency can be also improved.
[0017] When a polymer compound whose main chain has electron
transportability and side chain has an electron injection/transport
group, the electron transportability of the main chain can be
improved.
[0018] Likewise, by separating the function of the main chain from
that of the side chain, a function can be added without inhibiting
the function of the main chain, with the result that functional
improvement of a polymer compound can be expected.
[0019] Accordingly, a polymer LED containing a polymer compound
according to the present invention can be used as curved and planar
light sources for backlight or illumination of liquid crystal
displays and used in devices such as a segment type display device
and a flat panel display of dot matrix.
BEST MODE FOR CARRYING OUT THE INVENTION
[0020] A polymer compound according to the present invention has a
fluorenediyl group that may have a substituent in the main
chain.
[0021] The fluorenediyl group is represented by the following
formula (1).
##STR00002##
The compound represented by the formula (1), may have a
substituent.
[0022] When a fluorenediyl group has a substituent, the compound
may have substituents whose number is selected from the integers of
0 to 7, other than a functional side chain. The substituent(s) are
preferably selected from the group consisting of an alkyl group,
alkoxy group, alkylthio group, aryl group, aryloxy group, arylthio
group, arylalkyl group, arylalkoxy group, arylalkylthio group,
arylalkenyl group, arylalkynyl group, amino group, substituted
amino group, silyl group, substituted silyl group, halogen atom,
acyl group, acyloxy group, imine residue, amide group, acid imido
group, monovalent heterocyclic group, carboxyl group, substituted
carboxyl group, cyano group and nitro group.
[0023] The alkyl group may be linear, branched or cyclic and may
have a substituent. The number of carbon atoms is generally about 1
to 20. Specific examples thereof include a methyl group, ethyl
group, propyl group, isopropyl group, butyl group, isobutyl group,
t-butyl group, pentyl group, hexyl group, cyclohexyl group, heptyl
group, octyl group, 2-ethylhexyl group, nonyl group, decyl group,
3,7-dimethyloctyl group, lauryl group, trifluoromethyl group,
pentafluoroethyl group, perfluorobutyl group, perfluorohexyl group
and perfluorooctyl group.
[0024] The alkoxy group may be linear, branched or cyclic and may
have a substituent. The number of carbon atoms is generally about 1
to 20. Specific examples thereof include a methoxy group, ethoxy
group, propyloxy group, isopropyloxy group, butoxy group, isobutoxy
group, t-butoxy group, pentyloxy group, hexyloxy group,
cyclohexyloxy group, heptyloxy group, octyloxy group,
2-ethylhexyloxy group, nonyloxy group, decyloxy group,
3,7-dimethyloctyloxy group, lauryloxy group, trifluoromethoxy
group, pentafluoroethoxy group, perfluorobutoxy group,
perfluorohexyl group, perfluorooctyl group, methoxymethyloxy group
and 2-methoxyethyloxy group.
[0025] The alkylthio group may be linear, branched or cyclic and
may have a substituent. The number of carbon atoms is generally
about 1 to 20. Specific examples thereof include a methylthio
group, ethylthio group, propylthio group, isopropylthio group,
butylthio group, iso butylthio group, t-butylthio group, pentylthio
group, hexylthio group, cyclohexylthio group, heptylthio group,
octylthio group, 2-ethylhexylthio group, nonylthio group, decylthio
group, 3,7-dimethyloctylthio group, laurylthio group and
trifluoromethylthio group.
[0026] The aryl group is the remaining atom group obtained by
removing a single hydrogen atom from an aromatic hydrocarbon and
includes an aryl group having a condensed ring and an aryl group
having two or more independent benzene rings or condensed rings
directly joined thereto or joined via a group such as vinylene. The
aryl group generally has about 6 to 60 carbon atoms, and
preferably, 7 to 48 carbon atoms. Specific examples thereof include
a phenyl group, C.sub.1-C.sub.12alkoxyphenyl group
(C.sub.1-C.sub.12 represents that the number of carbon atoms is 1
to 12 and hereinafter, the same definition will be also applied),
C.sub.1-C.sub.12alkylphenyl group, 1-naphthyl group, 2-naphthyl
group, 1-anthracenyl group, 2-anthracenyl group, 9-anthracenyl
group and pentafluorophenyl group, and a
C.sub.1-C.sub.12alkoxyphenyl group and C.sub.1-C.sub.12alkylphenyl
group are preferable. Specific examples of the
C.sub.1-C.sub.12alkoxy include methoxy, ethoxy, propyloxy,
isopropyloxy, butoxy, isobutoxy, t-butoxy, pentyloxy, hexyloxy,
cyclohexyloxy, heptyloxy, octyloxy, 2-ethylhexyloxy, nonyloxy,
decyloxy, 3,7-dimethyloctyloxy and lauryloxy. Specific examples of
the C.sub.1-C.sub.12alkylphenyl group include a methylphenyl group,
ethylphenyl group, dimethylphenyl group, propylphenyl group,
mesityl group, methylethylphenyl group, isopropylphenyl group,
butylphenyl group, isobutylphenyl group, t-butylphenyl group,
pentylphenyl group, isoamylphenyl group, hexylphenyl group,
heptylphenyl group, octylphenyl group, nonylphenyl group,
decylphenyl group and dodecylphenyl group.
[0027] The aryloxy group generally has about 6 to 60 carbon atoms
and preferably 7 to 48. Specific examples thereof include a phenoxy
group, C.sub.1-C.sub.12alkoxyphenoxy group
C.sub.1-C.sub.12alkylphenoxy group, 1-naphthyloxy group,
2-naphthyloxy group and pentafluorophenyloxy group, and a
C.sub.1-C.sub.12alkoxyphenoxy group and
C.sub.1-C.sub.12alkylphenoxy group are preferable.
[0028] Specific examples of the C.sub.1-C.sub.12alkoxy include
methoxy, ethoxy, propyloxy, isopropyloxy, butoxy, isobutoxy,
t-butoxy, pentyloxy, hexyloxy, cyclohexyloxy, heptyloxy, octyloxy,
2-ethylhexyloxy, nonyloxy, decyloxy, 3,7-dimethyloctyloxy and
lauryloxy.
[0029] Specific examples of the C.sub.1-C.sub.12alkylphenoxy group
include a methylphenoxy group, ethylphenoxy group, dimethylphenoxy
group, propylphenoxy group, 1,3,5-timethylphenoxy group,
methylethylphenoxy group, isopropylphenoxy group, butylphenoxy
group, isobutylphenoxy group, t-butylphenoxy group, pentylphenoxy
group, isoamylphenoxy group, hexylphenoxy group, heptylphenoxy
group, octylphenoxy group, nonylphenoxy group, decylphenoxy group
and dodecylphenoxy group.
[0030] The arylthio group may have a substituent on the aromatic
ring and generally has about 3 to 60 carbon atoms. Specific
examples thereof include a phenylthio group,
C.sub.1-C.sub.12alkoxyphenylthio group,
C.sub.1-C.sub.12alkylphenylthio group, 1-naphthylthio group,
2-naphthylthio group, pentafluorophenylthio group, pyridylthio
group, pyridazinylthio group, pyrimidylthio group, pyrazylthio
group and triazylthio group.
[0031] The arylalkyl group may have a substituent and generally has
about 7 to 60 carbon atoms. Specific examples thereof include a
phenyl-C.sub.1-C.sub.12alkyl group,
C.sub.1-C.sub.12alkoxyphenyl-C.sub.1-C.sub.12alkyl group,
C.sub.1-C.sub.12alkylphenyl-C.sub.1-C.sub.12alkyl group,
1-naphthyl-C.sub.1-C.sub.12alkyl group and
2-naphthyl-C.sub.1-C.sub.12alkyl group.
[0032] The arylalkoxy group may have a substituent and generally
has about 7 to 60 carbon atoms. Specific examples thereof include a
phenyl-C.sub.1-C.sub.12alkoxy group,
C.sub.1-C.sub.12alkoxyphenyl-C.sub.1-C.sub.12alkoxy group,
C.sub.1-C.sub.12alxylphenyl-C.sub.1-C.sub.12alkoxy group,
1-naphthyl-C.sub.1-C.sub.12alkoxy group and
2-naphthyl-C.sub.1-C.sub.12alkoxy group.
[0033] The arylalkylthio group may have a substituent and generally
has about 7 to 60 carbon atoms. Specific examples thereof include a
phenyl-C.sub.1-C.sub.12alkylthio group,
C.sub.1-C.sub.12alkoxyphenyl-C.sub.1-C.sub.12alkylthio group,
C.sub.1-C.sub.12alxylphenyl-C.sub.1-C.sub.12alkylthio group,
1-naphthyl-C.sub.1-C.sub.12alkylthio group and
2-naphthyl-C.sub.1-C.sub.12alkylthio group.
[0034] The arylalkenyl group generally has about 8 to 60 carbon
atoms. Specific examples thereof include a
phenyl-C.sub.2-C.sub.12alkenyl group,
C.sub.1-C.sub.12alkoxyphenyl-C.sub.2-C.sub.12alkenyl group,
C.sub.1-C.sub.12alxylphenyl-C.sub.2-C.sub.12alkenyl group,
1-naphthyl-C.sub.2-C.sub.12alkenyl group and
2-naphthyl-C.sub.2-C.sub.12alkenyl group; and a
C.sub.1-C.sub.12alkoxyphenyl-C.sub.2-C.sub.12alkenyl group and
C.sub.2-C.sub.12alkylphenyl-C.sub.1-C.sub.12alkenyl group are
preferable.
[0035] The arylalkynyl group generally has about 8 to 60 carbon
atoms. Specific examples thereof include a
phenyl-C.sub.2-C.sub.12alkynyl group,
C.sub.1-C.sub.12alkoxyphenyl-C.sub.2-C.sub.12alkynyl group,
C.sub.1-C.sub.12alxylphenyl-C.sub.2-C.sub.12alkynyl group,
1-naphthyl-C.sub.2-C.sub.12alkynyl group and
2-naphthyl-C.sub.2-C.sub.12alkynyl group; and a
C.sub.1-C.sub.12alkoxyphenyl-C.sub.2-C.sub.12alkynyl group and
C.sub.1-C.sub.12alkylphenyl-C.sub.2-C.sub.12alkynyl group are
preferable.
[0036] The substituted amino group may include amino groups
substituted with a single group or two groups selected from the
group consisting of an alkyl group, aryl group, arylalkyl group and
a monovalent heterocyclic group. The alkyl group, aryl group,
arylalkyl group or a monovalent heterocyclic group may have a
substituent S. The number of carbon atoms of the substituted amino
group excluding that of the substituent S is generally about 1 to
60, and preferably, 2 to 48.
[0037] Specific examples include a methylamino group, dimethylamino
group, ethylamino group, diethylamino group, propylamino group,
dipropylamino group, isopropylamino group, diisopropylamino group,
butylamino group, isobutylamino group, t-butylamino group,
pentylamino group, hexylamino group, cyclohexylamino group,
heptylamino group, octylamino group, 2-ethylhexylamino group,
nonylamino group, decylamino group, 3,7-dimethyloctylamino group,
laurylamino group, cyclopentylamino group, dicyclopentylamino
group, cyclohexylamino group, dicyclohexylamino group, pyrrolidyl
group, piperidyl group, ditrifluoromethylamino group, phenylamino
group, diphenylamino group, C.sub.1-C.sub.12alkoxyphenylamino
group, di(C.sub.1-C.sub.12alkoxyphenyl)amino group,
di(C.sub.1-C.sub.12alkylphenyl)amino group, 1-naphthylamino group,
2-naphthylamino group, pentafluorophenylamino group, pyridylamino
group, pyridazinylamino group, pyrimidylamino group, pyrazylamino
group, triazylamino group phenyl-C.sub.1-C.sub.12alkylamino group,
C.sub.1-C.sub.12alkoxyphenyl-C.sub.1-C.sub.12alkylamino group,
C.sub.1-C.sub.12alkylphenyl-C.sub.1-C.sub.12alkylamino group,
di(C.sub.1-C.sub.12alkoxyphenyl-C.sub.1-C.sub.12alkyl)amino group,
di(C.sub.1-C.sub.12alkylphenyl-C.sub.1-C.sub.12alkyl)amino group,
1-naphthyl-C.sub.1-C.sub.12alkylamino group and
2-naphthyl-C.sub.1-C.sub.12alkylamino group.
[0038] The substituted silyl group may include silyl groups
substituted with 1, 2 or 3 groups selected from the group
consisting of an alkyl group, aryl group, arylalkyl group and a
monovalent heterocyclic group.
[0039] The substituted silyl group generally has about 1 to 60
carbon atoms, and preferably 3 to 48 carbon atoms. The alkyl group,
aryl group, aryloxy group or a monovalent heterocyclic group may
have a substituent. Note that the alkyl group, aryl group,
arylalkyl group and a monovalent heterocyclic group may have a
substituent.
[0040] Specific examples thereof include a trimethylsilyl group,
triethylsilyl group, tripropylsilyl group, tri-isopropylsilyl
group, dimethyl-isopropylsilyl group, diethyl-isopropylsilyl group,
t-butylsilyldimethylsilyl group, pentyldimethylsilyl group,
hexyldimethylsilyl group, heptyldimethylsilyl group,
octyldimethylsilyl group, 2-ethylhexyl-dimethylsilyl group,
nonyldimethylsilyl group, decyldimethylsilyl group,
3,7-dimethyloctyl-dimethylsilyl group, lauryldimethylsilyl group,
phenyl-C.sub.1-C.sub.12alkylsilyl group,
C.sub.1-C.sub.12alkoxyphenyl-C.sub.1-C.sub.12alkylsilyl group,
C.sub.1-C.sub.12alkylphenyl-C.sub.1-C.sub.12alkylsilyl group,
1-naphthyl-C.sub.1-C.sub.12alkylsilyl group,
2-naphthyl-C.sub.1-C.sub.12alkylsilyl group,
phenyl-C.sub.1-C.sub.12alkyldimethylsilyl group, triphenylsilyl
group, tri-p-xylylsilyl group, tribenzylsilyl group,
diphenylmethylsilyl group, t-butyldiphenylsilyl group and
dimethylphenylsilyl group.
[0041] Examples of the halogen atom include a fluorine atom,
chlorine atom, bromine atom and iodine atom.
[0042] The acyl group generally has about 2 to 20 carbon atoms, and
preferably, 2 to 18 carbon atoms. Specific examples thereof include
an acetyl group, propionyl group, butyryl group, isobutyryl group,
pivaloyl group, benzoyl group, trifluoroacetyl group and
pentafluorobenzoyl group.
[0043] The acyloxy group generally has about 2 to 20 carbon atoms,
and preferably, 2 to 18 carbon atoms. Specific examples thereof
include an acetoxy group, propionyloxy group, butyryloxy group,
isobutyryloxy group, pivaloyloxy group, benzoyloxy group,
trifluoroacetyloxy group and pentafluorobenzoyloxy group.
[0044] The imine residue has about 2 to 20 carbon atoms, and
preferably, 2 to 18 carbon atoms. Specific examples thereof
include
groups represented by the following formulas.
##STR00003##
[0045] The amide group has about 2 to 20 carbon atoms, and
preferably, 2 to 18 carbon atoms. Specific examples thereof include
a formamide group, acetamido group, propioamide group, butyroamide
group, benzamido group, trifluoroacetamido group,
pentafluorobenzamide group, diformamide group, diacetamide group,
dipropyoamide group; dibutyroamide group, dibenzamide group,
ditrifluoroacetamide group and dipentafluorobenzamide group.
[0046] The acid imido group may be a residue obtained by removing a
hydrogen atom bound to the nitrogen atom of the acid imido and has
about 4 to 20 carbon atoms. Specific examples thereof include
groups represented below.
##STR00004##
[0047] The monovalent heterocyclic group refers to an atom group
obtained by removing a single hydrogen atom from a heterocyclic
compound and generally has about 4 to 60 carbon atoms, and
preferably, 4 to 20 carbon atoms. Note that the number of carbon
atoms of the heterocyclic ring does not include the number of
carbon atoms of a substituent. The heterocyclic compound herein
refers to an organic compound having a ring structure which may not
be necessarily constituted of carbon atoms alone and may include a
hetero atom such as oxygen, sulfur, nitrogen, phosphorus or boron.
Specific examples thereof include a thienyl group,
C.sub.1-C.sub.12alkylthienyl group, pyrrolyl group, furyl group,
pyridyl group, C.sub.1-C.sub.12alkylpyridyl group, piperidyl group,
quinolyl group and isoquinolyl group; and a thienyl group,
C.sub.1-C.sub.12alkylthienyl group, pyridyl group and
C.sub.1-C.sub.12alkylpyridyl group are preferable.
[0048] The substituted carboxyl group is a carboxyl group
substituted with an alkyl group, aryl group, arylalkyl group or
monovalent heterocyclic group and generally has about 2 to 60
carbon atoms, and preferably, 2 to 48 carbon atoms. Specific
examples thereof include a methoxycarbonyl group, ethoxycarbonyl
group, propoxycarbonyl group, isopropoxycarbonyl group,
butoxycarbonyl group, isobutoxycarbonyl group, t-butoxycarbonyl
group, pentyloxycarbonyl group, hexyloxycarbonyl group,
cyclohexyloxycarbonyl group, heptyloxycarbonyl group,
octyloxycarbonyl group, 2-ethylhexyloxycarbonyl group,
nonyloxycarbonyl group, decyloxycarbonyl group,
3,7-dimethyloctyloxycarbonyl group, dodecyloxycarbonyl group,
trifluoromethoxycarbonyl group, pentafluoroethoxycarbonyl group,
perfluorobutoxycarbonyl group, perfluorohexyloxycarbonyl group,
perfluorooctyloxycarbonyl group, phenoxycarbonyl group,
naphthoxycarbonyl group and pyridyloxycarbonyl group. Note that the
alkyl group, aryl group, arylalkyl group or monovalent heterocyclic
group may have a substituent. Note that the number of carbon atoms
of the substituted carboxyl group mentioned above does not include
the number of carbon atoms of a substituent.
[0049] In view of ease of synthesis, of the repeat units shown in
the formula (1), repeat units represented by the following formulas
(1-1) and (1-2) are preferable.
##STR00005##
The compounds represented by formulas (1-1) and (1-2) may have a
substituent.
[0050] When the compounds represented by formulas (1-1) and (1-2)
have a substituent, they may have substituents whose number is
selected from the integers of 0 to 7, other than a functional side
chain. Examples of the substituent(s) are the same as those listed
in the formula (1).
[0051] Furthermore, a polymer compound according to the present
invention has a functional side chain containing at least one
functional group selected from the group consisting of a hole
injection/transport group containing at least one hetero atom other
than a nitrogen atom or at least two nitrogen atoms, an electron
injection/transport group containing at least one hetero atom other
than a nitrogen atom or at least two nitrogen atoms, and a light
emitting group containing a condensed polycyclic aromatic
hydrocarbon or a heterocyclic ring.
[0052] As the hole injection/transport group, mention may be made
of a monovalent group having hole injectability superior to that of
the main chain or a monovalent group having hole transportability
superior to the main chain.
[0053] The hole injectability generally depends upon the energy
value of the highest occupied molecular orbital (HOMO) of a polymer
compound. The smaller the absolute value of the HOMO energy value,
the better the hole injectability.
[0054] As the monovalent group having hole injectability superior
to that of the main chain, mention may be made of a monovalent
group having a lower absolute value of the HOMO energy than that of
the main chain.
[0055] The HOMO energy is obtained by measuring the oxidation
potential of a polymer compound by use of cyclic voltammetry (CV)
and calculating the energy based on the value of oxidation
potential. In the case of a polymer compound according to the
present invention, the oxidation potential takes a negative value.
The lower the oxidation potential (the larger the absolute value of
the oxidation potential), the smaller the absolute value of HOMO
energy. Thus, the hole injectability is improved. When HOMO energy
is calculated based on the value of oxidation potential, since a
calculation method varies depending upon the type of electrode and
solvent used in CV, calculation is made by correcting the error
between electrodes and solvents with reference to the
electrochemical handbook, the 5th edition (2000, published by
Maruzen Co., Ltd.).
[0056] The transportability of holes generally depends upon the
mobility of holes of a polymer compound. The higher the mobility of
holes, the better the hole injectability.
[0057] As the monovalent group having hole transportability
superior to that of the main chain, mention may be made of a
monovalent group having a higher mobility of holes than that of the
main chain.
[0058] The measurement of hole mobility is not particularly
limited; however, the mobility of holes of a polymer compound can
be measured by a Time-of-Flight (TOF) method.
[0059] As the electron injection/transport group, mention may be
made of a monovalent group having electron injectability superior
to that of the main chain or a monovalent group having electron
transportability superior to that of the main chain.
[0060] The electron injectability generally depends upon the energy
value of the lowest unoccupied molecular orbital (LUMO) of a
polymer compound. The larger the absolute value of the LUMO energy
value, the better the electron injectability.
[0061] As the monovalent group having electron injectability
superior to that of the main chain, mention may be made of a
monovalent group having a larger absolute value of LUMO than that
of the main chain.
[0062] The LUMO energy is obtained by measuring the reduction
potential of a polymer compound by use of cyclic voltammetry (CV)
and calculating the energy based on the value of reduction
potential. In the case of a polymer compound according to the
present invention, the reduction potential takes a negative value.
The higher the reduction potential (the smaller the absolute value
of the reduction potential), the larger the absolute value of LUMO
energy. Thus, the electron injectability is improved. When LUMO
energy is calculated based on the value of reduction potential,
since a calculation method varies depending upon the type of
electrode and solvent used in CV, calculation is made by correcting
the error between electrodes and solvents with reference to the
electrochemical handbook, the 5th edition (2000, published by
Maruzen Co., Ltd.).
[0063] The electron transportability generally depends upon the
mobility of electrons of a polymer compound. The higher the
mobility of electrons, the better the electron injectability.
[0064] As the monovalent group having electron transportability
superior to that of the main chain, mention may be made of a
monovalent group having a higher mobility of electrons than that of
the main chain.
[0065] The measurement of electron mobility is not particularly
limited; however, the mobility of electrons of a polymer compound
can be measured by a Time-of-Flight (TOF) method.
[0066] The light emitting group is a monovalent group emitting a
color different in wavelength from that of the main chain and
generally include a monovalent group having a smaller HOMO-LUMO gap
(difference in absolute value between HOMO and LUMO energy) than
that of the main chain.
[0067] The measurement of MONO and LUMO is performed in the same
manner as mentioned above.
[0068] Examples of the hole injection/transport group containing at
least one hetero atom other than a nitrogen atom or at least two
nitrogen atoms may include
[0069] a monovalent aromatic amine containing two or more nitrogen
atoms,
[0070] a monovalent carbazole derivative containing two or more
nitrogen atoms,
[0071] a monovalent metal complex containing two or more nitrogen
atoms,
[0072] a monovalent group containing at least one nitrogen atom and
at least one hetero atom other than the nitrogen atom(s), and
[0073] a monovalent group containing a hetero atom except a
nitrogen atom.
[0074] Examples of the monovalent aromatic amine containing two or
more nitrogen atoms include those represented by the following
formulas (H-1) to (H-14);
[0075] examples of the monovalent carbazole derivative containing
two or more nitrogen atoms include those represented by the
following formulas (H-15) to (H-19);
[0076] examples of the monovalent metal complex containing two or
more nitrogen atoms include those represented by the following
formulas (H-20) to (H-22);
[0077] examples of the monovalent group containing at least one
nitrogen atom and at least one hetero atom other than the nitrogen
atom(s) include the residues obtained by removing single R or a
hydrogen atom on R from those represented by the following formulas
(H-23) to (H-25); and
[0078] examples of the monovalent group containing a hetero atom
except a nitrogen atom include the residues obtained by removing
single R or a hydrogen atom on R from those represented by the
following formulas (H-26) to (H-29).
##STR00006## ##STR00007## ##STR00008## ##STR00009## ##STR00010##
##STR00011## ##STR00012##
[0079] In the formulas (H-1) to (H-29), R is preferably selected
from the group consisting of a hydrogen atom, alkyl group, alkoxy
group, alkylthio group, aryl group, aryloxy group, arylthio group,
arylalkyl group, arylalkoxy group, arylalkylthio group, arylalkenyl
group, arylalkynyl group, amino group, substituted amino group,
silyl group, substituted silyl group, halogen atom, acyl group,
acyloxy group, imine residue, amide group, acid imido group,
monovalent heterocyclic group, carboxyl group, substituted carboxyl
group, cyano group and nitro group.
[0080] Examples of the alkyl group, alkoxy group, alkylthio group,
aryl group, aryloxy group, arylthio group, arylalkyl group,
arylalkoxy group, arylalkylthio group, arylalkenyl group,
arylalkynyl group, substituted amino group, substituted silyl
group, halogen atom, acyl group, acyloxy group, imine residue,
amide group, acid imido group, monovalent heterocyclic group,
carboxyl group and substituted carboxyl group are the same as those
defined in the formula (1).
[0081] In the formula (H-26), R' is preferably selected from the
group consisting of a hydrogen atom, alkyl group, aryl group,
arylalkyl group, arylalkoxy group, arylalkylthio group, arylalkenyl
group, arylalkynyl group and monovalent heterocyclic group.
[0082] Examples of the alkyl group, aryl group, arylalkyl group,
arylalkoxy group, arylalkylthio group, arylalkenyl group,
arylalkynyl group and monovalent heterocyclic group are the same as
those defined in the formula (1).
[0083] The hole injection/transport group may be an oligomer or a
polymer.
[0084] Specific examples thereof may include the residue obtained
by removing a single R or a hydrogen atom on R from a compound in
which not less than two compounds that may be same or different in
type, are joined by carbon-to-carbon bound to R, as shown in the
aforementioned formulas (H-1) to (H-29).
[0085] Examples of the electron injection/transport group
containing at least one hetero atom other than a nitrogen atom or
at least two nitrogen atoms include
[0086] a monovalent Al or Zn complex containing at least one hetero
atom other than a nitrogen atom;
[0087] a monovalent complex of a metal except Al and Zn containing
at least one hetero atom except a nitrogen atom and an element
selected from the group consisting of elements of the second to
fourth period of the periodic table;
[0088] a monovalent group containing at least one hetero atom other
than a nitrogen atom and at least one nitrogen atom;
[0089] a monovalent group containing at least one sulfur atom alone
as a hetero atom; and
[0090] a monovalent group containing two or more nitrogen atoms
alone as a hetero atom.
[0091] Examples of the monovalent Al or Zn complex containing at
least one hetero atom other than a nitrogen atom include those
represented by the following formulas (E-1) to (E-10);
[0092] examples of the monovalent complex of a metal except Al and
Zn containing at least one hetero atom except a nitrogen atom and
an element selected from the group consisting of elements of the
second to fourth period of the periodic table include those
represented by the following formulas (E-11) to (E-16);
[0093] examples of the monovalent group containing at least one
hetero atom other than a nitrogen atom and at least one nitrogen
atom include the residues obtained by removing a single R or a
hydrogen atom on R from the following formulas (E-17) to
(E-27);
[0094] examples of the monovalent group containing at least one
sulfur atom alone as a hetero atom include the residues obtained by
removing a single R or a hydrogen atom on R from the following
formulas (E-28) to (E-31); and
[0095] examples of the monovalent group containing two or more
nitrogen atoms alone as a hetero atom include the residues obtained
by removing a single R or a hydrogen atom on R from the following
formulas (E-32) to (E-40).
##STR00013## ##STR00014## ##STR00015## ##STR00016## ##STR00017##
##STR00018## ##STR00019## ##STR00020## ##STR00021## ##STR00022##
##STR00023##
[0096] In the formulas (E-1) to (E-40), R can be defined as the
same as mentioned with respect to the formulas (H-1) to (H-29).
[0097] The electron injection/transport group may be an oligomer or
a polymer.
[0098] Specific examples thereof may include the residue obtained
by removing a single R or a hydrogen atom on R from a compound in
which not less than two compounds that may be same or different in
type, are joined by carbon-to-carbon to which R is bound, as shown
in the aforementioned formulas (E-1) to (E-40).
[0099] Examples of the monovalent Al or Zn complex containing at
least one hetero atom other than a nitrogen atom include those
represented by the following formulas (E-1) to (E-10);
[0100] examples of the monovalent complex of a metal except Al and
Zn containing at least one hetero atom except a nitrogen atom and
an element selected from the group consisting of elements of the
second to fourth period of the periodic table include those
represented by the following formulas (E-11) to (E-16);
[0101] examples of the monovalent group containing at least one
hetero atom other than a nitrogen atom and at least one nitrogen
atom include those represented by the following formulas (E-17) to
(E-27);
[0102] examples of the monovalent group containing at least one
sulfur atom alone as a hetero atom include those represented by the
following formulas (E-28) to (E-31); and
[0103] examples of the monovalent group containing two or more
nitrogen atoms alone as a hetero atom include those represented by
the following formulas (E-32) to (E-40).
[0104] Examples of the light emitting group containing a condensed
polycyclic aromatic hydrocarbon or a heterocyclic ring include
[0105] a monovalent condensed polycyclic aromatic hydrocarbon
group,
[0106] a monovalent group having two or more condensed polycyclic
aromatic hydrocarbon groups joined therein,
[0107] a monovalent heterocyclic group containing at least one
nitrogen atom and/or oxygen atom alone as a hetero atom, and
[0108] a monovalent heterocyclic group containing at least one
sulfur atom as a hetero atom.
[0109] Examples of the monovalent condensed polycyclic aromatic
hydrocarbon group include the residues obtained by removing a
single R or a hydrogen atom on R from the following formulas (L-1)
to (L-5);
[0110] examples of the monovalent group having two or more
condensed polycyclic aromatic hydrocarbon groups joined therein
include the residues obtained by removing a single R or a hydrogen
atom on R from the following formulas (L-6) to (L-8);
[0111] examples of the monovalent heterocyclic group containing at
least one nitrogen atom and/or oxygen atom alone as a hetero atom
include the residues obtained by removing a single R or a hydrogen
atom on R from the following formulas (L-9) to (L-15); and
[0112] examples of the monovalent heterocyclic group containing at
least one sulfur atom as a hetero atom include the residues
obtained by removing a single R or a hydrogen atom on R from the
following formulas (L-16) to (L-22).
##STR00024## ##STR00025## ##STR00026## ##STR00027##
##STR00028##
[0113] In the formulas (L-1) to (L-22), R can be defined as the
same as mentioned with respect to the formulas (H-1) to (H-29).
[0114] In the formulas (L-9), (L-10), (L-19) and (L-20), R' can be
defined as the same as mentioned with respect to the formula
(H-26).
[0115] The light-emitting group may be an oligomer and a
polymer.
[0116] Specific examples thereof may include the residue obtained
by removing a single R or a hydrogen atom on R from a compound in
which not less than two compounds that may be same or different in
type, are joined by carbon-to-carbon to which R is bound, as shown
in the aforementioned formulas (L-1) to (E-22).
[0117] The functional side chain may be present singly or two or
more different functional side chains may be present.
[0118] In view of improving hole transportability, the functional
side chain is preferably a hole injection/transport group; more
preferably
[0119] a monovalent aromatic amine containing two or more nitrogen
atoms,
[0120] a monovalent carbazole derivative containing two or more
nitrogen atoms,
[0121] a monovalent metal complex containing two or more nitrogen
atoms, or
[0122] a monovalent group containing at least one nitrogen atom and
at least one hetero atom other than the nitrogen atom(s);
[0123] further preferably,
[0124] a monovalent aromatic amine containing two or more nitrogen
atoms,
[0125] a monovalent carbazole derivative containing two or more
nitrogen atoms, or
[0126] a monovalent metal complex containing two or more nitrogen
atoms; and most preferably,
[0127] a monovalent aromatic amine containing two or more nitrogen
atoms, or
[0128] a monovalent carbazole derivative containing two or more
nitrogen atoms.
[0129] In view of improving hole injectability/transportability,
the functional side chain is preferably a monovalent group
represented by the following formula (H-A).
##STR00029##
[0130] In the formula (H-A), Ar.sub.101 and Ar.sub.102 each
independently represent an arylene group and a divalent
heterocyclic group or a divalent group having a metal complex
structure; Ar.sub.103, Ar.sub.104 and Ar.sub.105 each independently
represent an aryl group and a monovalent heterocyclic group;
Ar.sub.102, and Ar.sub.103, and Ar.sub.104 and Ar.sub.105 may be
mutually jointed to form a ring.
[0131] The aryl group and monovalent heterocyclic group are the
same as defined above.
[0132] The arylene group used herein refers to an atom group
obtained by removing two hydrogen atoms from an aromatic
hydrocarbon and includes an arylene group having a condensed ring,
and an aryl group having two or more independent benzene rings or
condensed rings directly joined thereto or joined via a group such
as vinylene. The arylene group may have a substituent.
[0133] The type of substituent is not particularly limited. In view
of solubility, fluorescent properties, ease of synthesis and
characteristics of the resultant device, preferable examples of the
substituent include an alkyl group, alkoxy group, alkylthio group,
aryl group, aryloxy group, arylthio group, arylalkyl group,
arylalkoxy group, arylalkylthio group, arylalkenyl group,
arylalkynyl group, amino group, substituted amino group, silyl
group, substituted silyl group, halogen atom, acyl group, acyloxy
group, imine residue, amide group, acid imido group, monovalent
heterocyclic group, carboxyl group, substituted carboxyl group,
cyano group and nitro group.
[0134] The number of carbon atoms of the arylene group except a
substituent is generally about 6 to 60, and preferably 6 to 20. The
total number of carbon atoms of the arylene group including that of
a substituent is generally about 6 to 100.
[0135] Examples of the arylene group include a phenylene group (for
example, the following formulas 1 to 3), naphthalene-diyl group
(the following formulas 4 to 13), anthracene-diyl group (the
following formulas 14 to 19), biphenyl-diyl group (the following
formulas 20 to 25), fluorene-diyl group (the following formulas 36
to 38), terphenyl-diyl group (the following formulas 26 to 28),
condensed ring compound group (the following formulas 29 to 35) and
indenonaphthalene-diyl (the following formulas G to N).
##STR00030## ##STR00031## ##STR00032## ##STR00033## ##STR00034##
##STR00035## ##STR00036## ##STR00037## ##STR00038##
[0136] The divalent heterocyclic group refers to the remaining atom
group obtained by removing two hydrogen atoms from a heterocyclic
compound and may have a substituent.
[0137] The heterocyclic compound refers to an organic compound
having a ring structure which may not be necessarily constituted of
carbon atoms alone and may include a hetero atom such as oxygen,
sulfur, nitrogen, phosphorus, boron or arsenic. Of the divalent
heterocyclic groups, an aromatic heterocyclic group is preferable.
The type of substituent is not particularly limited; however, in
view of solubility, fluorescent properties, ease of synthesis and
characteristics of the resultant device, preferable examples of the
substituent include an alkyl group, alkoxy group, alkylthio group,
aryl group, aryloxy group, arylthio group, arylalkyl group,
arylalkoxy group, arylalkylthio group, arylalkenyl group,
arylalkynyl group, amino group, substituted amino group, silyl
group, substituted silyl group, halogen atom, acyl group, acyloxy
group, imine residue, amide group, acid imido group, monovalent
heterocyclic group, carboxyl group, substituted carboxyl group,
cyano group and nitro group.
[0138] The number of carbon atoms of the divalent heterocyclic
group except that of a substituent is generally about 3 to 60. The
total number of carbon atoms of the divalent heterocyclic group
including that of a substituent is generally about 3 to 100.
[0139] Examples of the divalent heterocyclic group include
[0140] divalent pyridine-diyl groups (the following formulas 39 to
44),
[0141] diazaphenylene groups (the following formulas 45 to 48),
[0142] quinolinediyl groups (the following formulas 49 to 63),
[0143] quinoxalinediyl groups (the following formulas 64 to
68),
[0144] acridinediyl groups (the following formulas 69 to 72),
[0145] bipyridyldiyl groups (the following formulas 73 to 75),
andphenanthrolinediyl groups (the following formulas 76 to 78)
containing nitrogen as a hetero atom;
[0146] groups having a fluorene structure and containing oxygen,
silicon, nitrogen or selenium, etc., as a hetero atom (the
following formulas 79 to 93);
[0147] 5-membered heterocyclic groups containing oxygen, silicon,
nitrogen, sulfur, selenium, boron or phosphorus, etc., as a hetero
atom (the following formulas 94 to 98, O to Z, and AA to AC);
[0148] 5-membered condensed heterocyclic groups containing oxygen,
silicon, nitrogen, sulfur or selenium, etc., as a hetero atom (the
following formulas 99 to 110);
[0149] dimmers or oligomers formed of 5-membered heterocyclic
groups containing oxygen, silicon, nitrogen, sulfur or selenium,
etc., as a hetero atom and joined at the .alpha.-position of the
hetero atom the following formulas III and 112);
[0150] 5-membered heterocyclic groups containing oxygen, silicon,
nitrogen, sulfur or selenium, etc., as a hetero atom and joined to
a phenyl group at the .alpha.-position of the hetero atom (the
following formulas 113 to 119);
[0151] 5-membered condensed heterocyclic groups containing oxygen,
silicon, nitrogen, sulfur or selenium, etc., as a hetero atom and
substituted with a phenyl group, furyl group, thienyl group (the
following formulas 120 to 125); and
[0152] 6-membered heterocyclic groups (the following formulas AD to
AG) containing oxygen and nitrogen as hetero atoms.
##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043##
##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048##
##STR00049## ##STR00050## ##STR00051## ##STR00052## ##STR00053##
##STR00054## ##STR00055## ##STR00056##
[0153] The divalent group having a metal complex structure in
Ar.sub.1 refers to a divalent group obtained by removing two
hydrogen atoms from an organic ligand of a metal complex having the
organic ligand.
[0154] The number of carbon atoms of the organic ligand is
generally about 4 to 60. Examples thereof include 8-quinolinol and
a derivative thereof, benzoquinolinol and a derivative thereof,
2-phenyl-pyridine and a derivative thereof, 2 phenyl-benzothiazole
and a derivative thereof, 2 phenyl-benzoxazole and a derivative
thereof, and porphyrin and a derivative thereof.
[0155] Examples of the core metal of the complex include aluminum,
zinc, beryllium, iridium, platinum, gold, europium and terbium.
[0156] Examples of the metal complex having an organic ligand
include metal complexes known as a low-molecular weight fluorescent
material and phosphorescent material and triplet light-emitting
complexes.
[0157] Specific examples of the divalent group having a metal
complex structure include those represented by the following
formulas 126 to 132.
##STR00057## ##STR00058## ##STR00059##
[0158] In the aforementioned formulas 1 to 132, R can be defined as
the same as mentioned with respect to the formulas (H-1) to
(H-29).
[0159] In view of synthesis, Ar.sub.102 preferably an arylene
group, and further preferably, a group represented by any one of
the formulas 1 to 19.
[0160] In view of synthesis, Ar.sub.103, Ar.sub.104, and Ar.sub.105
are preferably each independently an aryl group, and further
preferably, a phenyl group, 1-naphthyl group, 2-naphthyl groups,
1-anthracenyl group, 2-anthracenyl group or 9-anthracenyl
group.
[0161] In view of synthesis, Ar.sub.101 is preferably an arylene
group.
[0162] When Ar.sub.102 and Ar.sub.103, and Ar.sub.104 and
Ar.sub.105 each form a ring, the ring is preferably formed via -JJ-
(-JJ- represents direct bonding, --O--, --S-- and
--CH.sub.2--).
[0163] In view of improving electron transportability, a functional
side chain is preferably an electron injection/transport group;
more preferably
[0164] a monovalent Al or Zn complex containing at least one hetero
atom other than a nitrogen atom;
[0165] a monovalent complex except Al and Zn complexes containing
at least one hetero atom except a nitrogen atom and en element
selected from the group consisting of the elements of the second to
fourth period of the periodic table;
[0166] a monovalent group containing at least one sulfur atom alone
as a hetero atom; or
[0167] a monovalent group containing two or more nitrogen atoms
alone as a hetero atom; and
[0168] further preferably
[0169] a monovalent Al or Zn complex containing at least one hetero
atom other than a nitrogen atom;
[0170] a monovalent group containing at least one sulfur atom alone
as a hetero atom; or
[0171] a monovalent group containing two or more nitrogen atoms
alone as a hetero atom.
[0172] Furthermore, in view of improving electron transportability,
a functional side chain is preferably a monovalent group
represented by any one of the following formulas (E-A) to
(E-C).
##STR00060##
[0173] In the formulas (E-A) to (E-C), Ar.sub.107 to Ar.sub.111 are
each independently an arylene group, a divalent heterocyclic group
or a divalent group having a metal complex structure; Ar.sub.106,
Ar.sub.108, Ar.sub.109 and Ar.sub.110 are each independently an
aryl group and a monovalent heterocyclic group; Q.sub.1 is an
oxygen atom, sulfur atom or --N(R.sub.101)--; Q.sub.2, Q.sub.3,
Q.sub.4 Q.sub.5, and Q.sub.6 represents a nitrogen atom or
--C(R.sub.102)--; and R.sub.101 and R.sub.102 are the same groups
as those defined above in the case of R.
[0174] The arylene group, divalent heterocyclic group, divalent
group having a metal complex structure, aryl group and monovalent
heterocyclic group are the same as defined above.
[0175] In view of improving electron
injectability/transportability, Ar.sub.106 of the aforementioned
formula (E-A) is preferably a monovalent heterocyclic group.
[0176] In view of synthesis, Ar.sub.107 of the aforementioned
formula (E-B) is preferably a divalent heterocyclic group and any
one of the groups represented by the formulas 39 to 72 and 111 to
125.
[0177] Furthermore, in view of synthesis, Ar.sub.108 of the
aforementioned formula (E-B) is preferably a monovalent
heterocyclic group.
[0178] Furthermore, in view of synthesis, Ar.sub.109 and Ar.sub.110
of the aforementioned formula (E-C) are preferably each
independently an aryl group, and further preferably, a phenyl
group, 1-naphthyl group, 2-naphthyl group, 1-anthracenyl group,
2-anthracenyl group, or 9-anthracenyl group.
[0179] Furthermore, in view of synthesis, A.sub.111 is preferably
an arylene group, and further preferably, any one of the groups
represented by the formulas 1 to 19.
[0180] In view of improving an electron
injectability/transportability, of the formulas (E-A) to (E-C), the
formulas (E-A) and (E-B) are preferable and the formula (E-B) is
further preferable.
[0181] In view of improving light emission efficiency, a functional
side chain is preferably a light-emitting group;
[0182] more preferably,
[0183] a monovalent condensed polycyclic aromatic hydrocarbon
group,
[0184] a monovalent group having two or more condensed polycyclic
aromatic hydrocarbon groups joined therein, or
[0185] a monovalent heterocyclic group containing at least one
nitrogen atom and/or oxygen atom alone as a hetero atom; and
further preferably,
[0186] a monovalent group having two or more condensed polycyclic
aromatic hydrocarbon groups joined therein, or
[0187] a monovalent heterocyclic group containing at least one
nitrogen atom and/or oxygen atom alone as a hetero atom.
[0188] In view of improving light emission efficiency, a functional
side chain is preferably a monovalent group containing a partial
structure represented by (L-A) or (L-B).
##STR00061##
[0189] In the formula (L-A) or (L-B), Q.sub.7 and Q.sub.8 represent
an oxygen atom, sulfur atom, --C(R.sub.103R.sub.104)--,
--Si(R.sub.105R.sub.106)--, --N(R.sub.107)--, --C(.dbd.O)--, or
--S(.dbd.O)--; Q.sub.9, Q.sub.10, Q.sub.11 and Q.sub.12 represent a
nitrogen atom or --C(R.sub.108)--; and R.sub.103 to R.sub.108
represent the same groups as those defined above in the case of
R.
[0190] In view of improving light emission efficiency, Q.sub.7 and
Q.sub.8 represent an oxygen atom, --C(R.sub.103R.sub.104)--,
--N(R.sub.107)--, and --C(.dbd.O)--; and further preferably, an
oxygen atom, --N(R.sub.107)--, and --C(.dbd.O)--.
[0191] In view of improving light emission efficiency, Q.sub.9,
Q.sub.10, Q.sub.11 and Q.sub.12 are preferably
--C(R.sub.108)--.
[0192] A polymer compound according to the present invention is
characterized in that a functional group contained in a functional
side chain is directly bonded to a saturated carbon of a
fluorenediyl group or bonded to the fluorenediyl group via
--R.sub.k--X-- (R.sub.k represents an alkylene group and X
represents a direct bond or bonding group) at X.
[0193] The "functional group is directly bonded to a saturated
carbon of a fluorenediyl group" means that a functional group of
the functional side chain is directly bonded to the 9th carbon atom
of the fluorenediyl group shown in the following formula.
##STR00062##
[0194] When a functional group is bonded to the fluorenediyl group
via --R.sub.k--X-- at X, R.sub.k represents an alkylene group. The
alkylene group may have a substituent and generally has about 1 to
12 carbon atoms. Examples of the substituent include an alkyl
group, alkoxy group, alkylthio group, aryl group, aryloxy group,
arylthio group, arylalkyl group, arylalkoxy group, arylalkylthio
group, arylalkenyl group, arylalkynyl group, amino group,
substituted amino group, silyl group, substituted silyl group,
halogen atom, acyl group, acyloxy group, imine residue, amide
group, acid imido group, monovalent heterocyclic group, carboxyl
group, substituted carboxyl group and cyano group. Note that the
number of carbon atoms of the alkylene group does not include the
number of a substituent(s).
[0195] Preferable examples of the alkylene group include
--C.sub.3H.sub.6--, --C.sub.4H.sub.8--, --C.sub.5H.sub.10--,
--C.sub.6H.sub.12--, --C.sub.8H.sub.16--, and
--C.sub.10H.sub.20--.
[0196] Furthermore, X represents a bonding group. Examples of the
bonding group include --O--, --S--, --CO--, --CO.sub.2--, --SO--,
--SO.sub.2--, --SiR.sup.1R.sup.2--, --NR.sup.3--, --BR.sup.4--,
--PR.sup.5-- and --P(.dbd.O)(R.sup.6)--. Bonding groups --O--,
--S-- and --NR.sup.3-- are preferable and --O-- and --NR.sup.3--
are more preferable.
[0197] R.sup.1 to R.sup.6 herein represent a hydrogen atom, alkyl
group, aryl group, arylalkyl group or a monovalent heterocyclic
group.
[0198] In view of synthesis, the 9th position of a fluorenediyl
group is preferably substituted with a functional group.
[0199] In view of synthesis, a functional group is preferably
directly bonded to the 9th position of a fluorenediyl group and
further preferably has two functional substituents at the 9th
position of a fluorenediyl group.
[0200] One of the desirable characteristics of a polymer compound
for a polymer LED is hole injectability. The hole injectability
generally depends upon the energy value of the highest occupied
molecular orbital (HOMO) of a polymer compound. The smaller the
absolute value of the HOMO energy, the better the hole
injectability. In a polymer compound according to the present
invention, in view of hole injectability, the absolute value of the
HOMO energy is preferably 5.6 eV or less; further preferably, 5.5
eV or less; and most preferably, 5.4 eV or less.
[0201] The HOMO energy is obtained by measuring the oxidation
potential of a polymer compound by use of cyclic voltammetry (CV)
and calculating the energy based on the value of oxidation
potential. In the case of a polymer compound according to the
present invention, the oxidation potential takes a negative value.
The lower the oxidation potential (the larger the absolute value of
the oxidation potential), the smaller the absolute value of HOMO
energy. Thus, the hole injectability is improved.
[0202] One of the desirable characteristics of a polymer compound
for a polymer LED is electron injectability. The electron
injectability generally depends upon the energy value of the lowest
unoccupied molecular orbital (LUMO) of a polymer compound. The
larger the absolute value of the LUMO energy value, the better the
electron injectability. In a polymer compound according to the
present invention, in view of electron injectability, the absolute
value of the LUMO energy is preferably 2.2 eV or more; further
preferably, 2.4 eV or more; and most preferably, 2.5 eV or
more.
[0203] Similarly to the case of the HOMO energy calculation, the
LUMO energy is obtained by measuring the reduction potential of a
polymer compound by use of cyclic voltammetry (CV) and calculating
the energy based on the value of reduction potential. In the case
of a polymer compound according to the present invention, the
reduction potential takes a negative value. The higher the
reduction potential (the smaller the absolute value of the
reduction potential), the larger the absolute value of LUMO energy.
Thus, the electron injectability is improved.
[0204] A polymer compound according to the present invention, in
view of life property of a device, the number average molecular
weight in terms of polystyrene is preferably 10.sup.3 to 10.sup.8;
more preferably, 10.sup.3 to 10.sup.7; and most preferably,
10.sup.4 to 10.sup.7.
[0205] The number average molecular weight and the weight average
molecular weight used herein were obtained in terms of polystyrene
in accordance with size exclusion chromatography (SEC)(LC-10Avp
manufactured by Shimadzu Corporation). The polymer to be measured
was dissolved in tetrahydrofuran so as to obtain a concentration of
about 0.5 wt %. 50 .mu.l of the resultant solution was poured in
GPC. Tetrahydrofuran was used as the mobile phase of the GPC and
supplied at a flow rate of 0.6 mL/min. The column was prepared by
serially connecting two columns of TSKgel SuperHM-H (manufactured
by Tosoh Corporation) directly to a single column of TSKgel Super
H2000 (manufactured by Tosoh Corporation). As a detector, a
differential refractive index detector (RID-10A, manufactured by
Shimadzu Corporation) was used.
[0206] Preferable examples of the polymer compound to be used in
the present invention will be described herein.
[0207] In view of light emission efficiency, durability of a device
and ease of synthesis,
[0208] the repeat unit of the main chain is the following formulas
(1-1-1) to (1-1-6) or (1-2-1) to (1-2-6) are preferable.
[0209] The polymers represented by the formulas (1-1-1) to (1-1-6)
and (1-2-1) to (1-2-6) may have a substituent.
[0210] Examples of the substituent may be the same as mentioned
above.
##STR00063## ##STR00064##
where, -J- represents --R.sub.k--X--; R.sub.k and X are the same as
defined above; R.sub.k is bonded to Fun; Fun represents a
functional side chain containing
[0211] a hole injection/transport group containing at least one
hetero atom other than a nitrogen atom or at least two nitrogen
atoms, (and/or)
[0212] an electron injection/transport group containing at least
one hetero atom other than a nitrogen atom or at least two nitrogen
atoms, and/or
[0213] a light emitting group containing a condensed polycyclic
aromatic hydrocarbon or a heterocyclic ring;
[0214] R.sub.w1 to R.sub.w4 and R.sub.x1 to R.sub.x4 each
independently represent a hydrogen atom, alkyl group, alkoxy group,
alkylthio group, aryl group, aryloxy group, arylthio group,
arylalkyl group, arylalkoxy group, arylalkylthio group, arylalkenyl
group, arylalkynyl group, amino group, substituted amino group,
silyl group, substituted silyl group, halogen atom, acyl group,
acyloxy group, imine residue, amide group, acid imido group,
monovalent heterocyclic group, carboxyl group, substituted carboxyl
group, cyano group or nitro group; and
[0215] Rw and Rx may be mutually bound to form a ring.
[0216] R.sub.k and X are the same as those defined above.
[0217] In view of light emission efficiency, durability of a device
and ease of synthesis, in the aforementioned formulas (1-1-1) to
(1-1-6) and (1-2-1) to (1-2-6),
[0218] when the alkylene group represented by R.sub.k in J has a
substituent, the substituent is preferably an alkyl group, alkoxy
group, alkylthio group, aryl group, aryloxy group, arylthio group,
arylalkyl group, arylalkoxy group, arylalkylthio group, arylalkenyl
group, arylalkynyl group and a monovalent heterocyclic group; more
preferably an alkyl group, alkoxy group, alkylthio group, aryl
group, aryloxy group, arylthio group, arylalkyl group, arylalkoxy
group and a monovalent heterocyclic group; further preferably an
alkyl group, alkoxy group, aryl group and a monovalent heterocyclic
group; and most preferably an alkyl group, alkoxy group and aryl
group.
[0219] In view of light emission efficiency, durability of an
element, and ease of synthesis, when X is a bonding group, X is
preferably --O--, --S--, --CO--, --, --SiR.sup.1R.sup.2--,
--NR.sup.3--, or --BR.sup.4--, and more preferably --O--, --S-- and
--SiR.sup.1R.sup.2--, or --NR.sup.3--, further preferably, --O--,
--S-- or --NR.sup.3--, and most preferably, --O--, or
--NR.sup.3--.
[0220] Examples of the hole injection/transport group containing at
least one hetero atom other than a nitrogen atom or at least two
nitrogen atoms, and/or
[0221] the electron injection/transport group containing at least
one hetero atom other than a nitrogen atom or at least two nitrogen
atoms, and/or
[0222] the light emitting group containing a condensed polycyclic
aromatic hydrocarbon or a heterocyclic ring, are the same as
defined above.
[0223] In view of light emission efficiency, durability of a device
and ease of synthesis, in the aforementioned formulas (1-1-1) to
(1-1-6) and (1-2-1) to (1-2-6), when Fun is a hole
injection/transport group,
[0224] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (H-1) to (H-29) are preferable;
[0225] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (H-1) to (H-3), (H-5) and (H-15) to
(H-17) are more preferable; and
[0226] the residue obtained by removing a single R or a hydrogen
atom on R from the formulas (H-1), (H-2), (H-15) and (H-16) are
further preferable.
[0227] In view of light emission efficiency, durability of a device
and ease of synthesis, in the aforementioned formulas (1-1-1) to
(1-1-6) and (1-2-1) to (1-2-6), when Fun is an electron
injection/transport group,
[0228] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (E-1) to (E-40) are preferable,
[0229] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (E-1) to (E-10) and (E-28) to (E-31)
are more preferable;
[0230] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (E-1), (E-2), (E-4) to (E-6) (E-28) and
(E-31) are further preferable; and
[0231] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (E-1), (E-2), (E-28) and (E-31) are
most preferable.
[0232] In view of light emission efficiency, durability of a device
and ease of synthesis, in the aforementioned formulas (1-1-1) to
(1-1-6) and (1-2-1) to (1-2-6), when Fun is a light-emitting
group,
[0233] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (L-1) to (L-22) are preferable;
[0234] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (L-6) to (L-8) and (L-9) to (L-16) are
more preferable;
[0235] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (L-6), (L-7), and (L-9) to (L-14) are
further preferable; and
[0236] the residues obtained by removing a single R or a hydrogen
atom on R from the formulas (L-6), (L-7) and (L-9) to (L-14) are
most preferable.
[0237] In view of light emission efficiency, durability of a device
and ease of synthesis, in the aforementioned formulas (H-1) to
(H-29), (E-1) to (E-40) and (L-1) to (L-22), R is preferably a
hydrogen atom, alkyl group, alkoxy group, alkylthio group, aryl
group, aryloxy group, arylthio group, arylalkyl group, arylalkoxy
group, arylalkylthio group, arylalkenyl group, arylalkynyl group or
a monovalent heterocyclic group; more preferably a hydrogen atom,
alkyl group, alkoxy group, alkylthio group, aryl group, aryloxy
group, arylthio group, arylalkyl group, arylalkoxy group or a
monovalent heterocyclic group; further preferably, a hydrogen atom,
alkyl group, alkoxy group, aryl group or a monovalent heterocyclic
group; and most preferably, a hydrogen atom, alkyl group, alkoxy
group or aryl group.
[0238] In view of light emission efficiency, durability of a device
and ease of synthesis, of the aforementioned formulas (1-1-1) to
(1-1-6) and (1-2-1) to (1-2-6), the repeat unit of the main chain
is,
[0239] preferably the formulas (1-1-1) to (1-1-4) or (1-2-1) to
(1-2-4); and
[0240] more preferably the formulas (1-1-2), (1-1-4), (1-2-2) or
(1-2-4).
[0241] In view of light emission efficiency, durability of a device
and ease of synthesis, when the groups represented by the formulas
(1-1-1) to (1-1-6) and (1-2-1) to (1-2-6) have a substituent, the
substituent is
[0242] preferable an alkyl group, alkoxy group, alkylthio group,
aryl group, aryloxy group, arylthio group, arylalkyl group,
arylalkoxy group, arylalkylthio group, arylalkenyl group,
arylalkynyl group or a monovalent heterocyclic group;
[0243] more preferable an alkyl group, alkoxy group, alkylthio
group, aryl group, aryloxy group, arylthio group, arylalkyl group,
arylalkoxy group or a monovalent heterocyclic group; and
[0244] further preferable an alkyl group, alkoxy group, aryl group
or a monovalent heterocyclic group; and
[0245] most preferably, an alkyl group, alkoxy group or aryl
group.
[0246] Specific examples of a polymer compound according to the
present invention will be described herein.
[0247] When a side chain has a hole injection/transport group,
those represented by (5-1-1) to (5-4-2) are mentioned as
examples.
[0248] When a side chain has an electron injection/transport group,
those represented by (6-1) to (6-4-2) are mentioned as
examples.
[0249] When a side chain has a light emitting group, those
represented by (7-1) to (7-4-2) are mentioned as examples.
##STR00065## ##STR00066## ##STR00067## ##STR00068## ##STR00069##
##STR00070## ##STR00071## ##STR00072## ##STR00073## ##STR00074##
##STR00075## ##STR00076## ##STR00077## ##STR00078## ##STR00079##
##STR00080## ##STR00081## ##STR00082## ##STR00083## ##STR00084##
##STR00085## ##STR00086## ##STR00087## ##STR00088## ##STR00089##
##STR00090## ##STR00091## ##STR00092## ##STR00093## ##STR00094##
##STR00095## ##STR00096## ##STR00097## ##STR00098## ##STR00099##
##STR00100## ##STR00101## ##STR00102## ##STR00103## ##STR00104##
##STR00105##
[0250] A polymer compound according to the present invention is
preferably a copolymer containing the aforementioned repeat unit
and one or more other types of repeat units in view of changing
light emission wavelength, improving light emission efficiency and
improving heat resistance. Examples of the "other types of repeat
units" preferably include those represented by the following
formula (8).
--Ar.sub.1-- (8)
where Ar.sub.1 is each independently represents an arylene group,
divalent heterocyclic group or divalent group having a metal
complex structure.
[0251] Examples of the arylene group, divalent heterocyclic group
or divalent group having a metal complex structure include the same
groups as mentioned above.
[0252] Of the repeat units represented by the aforementioned
formula (8), those represented by the following formulas (9), (10),
(11) or (12) are preferable.
##STR00106##
where R.sub.a represents an alkyl group, alkoxy group, alkylthio
group, aryl group, aryloxy group, arylthio group, arylalkyl group,
arylalkoxy group, arylalkylthio group, arylalkenyl group,
arylalkynyl group, amino group, substituted amino group, silyl
group, substituted silyl group, halogen atom, acyl group, acyloxy
group, imine residue, amide group, acid imido group, monovalent
heterocyclic group, carboxyl group, substituted carboxyl group,
cyano group or nitro group; a represents an integer from 0 to 4;
and when a plurality of R.sub.a are present, they may be the same
or different.
##STR00107##
where
[0253] R.sub.b and R.sub.c are each independently an alkyl group,
alkoxy group, alkylthio group, aryl group, aryloxy group, arylthio
group, arylalkyl group, arylalkoxy group, arylalkylthio group,
arylalkenyl group, arylalkynyl group, amino group, substituted
amino group, silyl group, substituted silyl group, halogen atom,
acyl group, acyloxy group, imine residue, amide group, acid imido
group, monovalent heterocyclic group, carboxyl group, substituted
carboxyl group, cyano group or nitro group;
[0254] b and c each independently represent an integer from 0 to
3;
[0255] and
[0256] when a plurality of R.sub.b and R.sub.C are present, they
may be the same or different.
##STR00108##
where
[0257] R.sub.d represents an alkyl group, alkoxy group, alkylthio
group, aryl group, aryloxy group, arylthio group, arylalkyl group,
arylalkoxy group, arylalkylthio group, arylalkenyl group,
arylalkynyl group, amino group, substituted amino group, silyl
group, substituted silyl group, halogen atom, acyl group, acyloxy
group, imine residue, amide group, acid imido group, monovalent
heterocyclic group, carboxyl group, substituted carboxyl group,
cyano group or nitro group;
[0258] d represents an integer from 0 to 2;
[0259] Ar.sub.9 and Ar.sub.10 each independently represent an
arylene group, divalent heterocyclic group or a divalent group
having a metal complex;
[0260] m and n, each independently represent 0 or 1;
[0261] X.sub.1 is O, S, SO, SO.sub.2, Se or Te; and
[0262] when a plurality of R.sub.d are present, they may be the
same or different.
##STR00109##
where
[0263] R.sub.e and R.sub.f each independently represent an alkyl
group, alkoxy group, alkylthio group, aryl group, aryloxy group,
arylthio group, arylalkyl group, arylalkoxy group, arylalkylthio
group, arylalkenyl group, arylalkynyl group, amino group,
substituted amino group, silyl group, substituted silyl group,
halogen atom, acyl group, acyloxy group, imine residue, amide
group, acid imido group, monovalent heterocyclic group, carboxyl
group, substituted carboxyl group, cyano group or nitro group;
[0264] e and f each independently represent an integer from 0 to
4;
[0265] X.sub.2 is O, S, SO, SO.sub.2, Se, Te N--R.sup.7 or
SiR.sup.8R.sup.9;
[0266] X.sub.3 and X.sub.4 each independently represent N or
C--R.sup.10;
[0267] R.sup.7, R.sup.8, R.sup.9 and R.sup.10 each independently
represent a hydrogen atom, alkyl group, aryl group, arylalkyl group
or a monovalent heterocyclic group; and
[0268] when a plurality of R.sub.c, R.sub.f and R.sup.10 are
present, they may be the same or different.
[0269] Examples of the 5-membered ring at the center of the repeat
unit represented by formula (12) include thiadiazole, oxadiazole,
triazole, thiophene, furan and silole.
[0270] The repeat units represented by the aforementioned formula
(13) are preferable included also in view of changing light
emission wavelength, improving light emission efficiency and
improving heat resistance.
##STR00110##
where Ar.sub.4, Ar.sub.5, Ar.sub.6 and Ar.sub.7 each independently
represent an arylene group or a divalent heterocyclic group;
Ar.sub.8, Ar.sub.9 and Ar.sub.10 each independently represent an
aryl group or a monovalent heterocyclic group; Ar.sub.4, Ar.sub.5,
Ar.sub.6, Ar.sub.7 and Ar.sub.8 may have a substituent; and o and p
each independently represent an integer of 0 or 1 and
0.ltoreq.o+p.ltoreq.1.
[0271] Specific examples of the repeat unit represented by the
aforementioned formula (13) include those represented by the
following formulas 133 to 140.
##STR00111## ##STR00112## ##STR00113##
[0272] In the aforementioned formulas, R is the same as that in the
cases of aforementioned formulas 1 to 132. To increase solubility
of a polymer compound to a solvent, the polymer compound is
preferably at least one atom other than a hydrogen atom, and
symmetricalness in shape of a repeat unit including a substituent
is preferably low.
[0273] In the aforementioned formulas, when R is a substituent
including alkyl, in order to increase solubility of a polymer
compound in a solvent, at least one cyclic or branched alkyl is
preferably contained.
[0274] Furthermore, in the aforementioned formulas, when R partly
contains an aryl group and a heterocyclic group, these groups may
have one or more substituents.
[0275] In the repeat unit represented by the aforementioned Formula
(13), it is preferable that Ar.sub.4, Ar.sub.5, Ar.sub.6 and
Ar.sub.7 each independently represent an arylene group; Ar.sub.8,
Ar.sub.9 and Ar.sub.10 each independently represent an aryl
group.
[0276] Of them, Ar.sub.8, Ar.sub.9 and Ar.sub.10 preferably each
independently represent an aryl group having 3 or more
substituents; more preferably a phenyl group having 3 or more
substituents, a naphthyl group having 3 or more substituents, or an
anthranyl group having 3 or more substituents; and further
preferably, a phenyl group having 3 or more substituents.
[0277] Of them, it is preferable that Ar.sub.8, Ar.sub.9 and
Ar.sub.10 each independently represent the following formula (13-1)
and satisfy the relationship: o+p=1.
##STR00114##
[0278] where R.sup.11, R.sup.12 and R.sup.13 each independently
represent an alkyl group, alkoxy group, alkylthio group, aryl
group, aryloxy group, arylthio group, arylalkyl group, arylalkoxy
group, arylalkylthio group, arylalkenyl group, arylalkynyl group,
amino group, substituted amino group, silyl group, substituted
silyl group, silyloxy group, substituted silyloxy group, monovalent
heterocyclic group, or halogen atom.
[0279] More preferably, in the formula (13-1), R.sub.11 and
R.sub.13 each independently represent an alkyl group having 3 or
less carbon atoms, alkoxy group having 3 or less carbon atoms or
alkylthio group having 3 or less carbon atoms; and R.sub.12 is an
alkyl group having 3 to 20 carbon atoms, alkoxy group having 3 to
20 carbon atoms or alkylthio group having 3 to 20 carbon atoms.
[0280] In view of light emission efficiency, the repeat unit
represented by the aforementioned formula (8) is preferably a
condensed ring and more preferably a divalent group represented by
any one of the aforementioned formulas 30 to 38, G to N, 49 to 93,
O to Z and AA to AC.
[0281] Of them, in view of synthesis, divalent groups represented
by the aforementioned formulas 30 to 32, 36, G, J, K, M, 49 to 68,
79 to 93 are preferable; and divalent groups represented by the
aforementioned formula 30, 31, 36, G, K, M, 54, 65, 67, 79, 82, 83,
87, and 93 are more preferable; and divalent groups represented by
the aforementioned formula 36, G, K, 79, 82, 83, 87 and 93 are
further preferable.
[0282] A polymer compound according to the present invention may be
a random, block or graft copolymer, a polymer having an
intermediate structure between them, for example, a random
copolymer analogous to a block copolymer. In view of obtaining a
light-emitting polymer having a high yield of fluorescent and
phosphorescent quantum, a random copolymer analogous to a block
copolymer, a block polymer or graft copolymer is more preferable
than a complete random copolymer. Not only copolymers having a
branched main chain and three or more terminal ends but also a
dendrimer are included.
[0283] In a polymer compound according to the present invention, if
a polymerizable group is left as the terminal group thereof, light
emission property and lifespan of the resultant device using the
polymer may decrease. Therefore the terminal group may be protected
by a stable group. The stable group having a conjugate bond
continued to the conjugation structure of the main chain is
preferable, for example, a structure bonded to an aryl group or a
heterocyclic group via a carbon-to-carbon bond may be mentioned.
Specific examples thereof include substituents shown in Formula 10
of JP-A-09-45478.
[0284] Examples of a good solvent for a polymer compound according
to the present invention include chloroform, methylene chloride,
dichloroethane, tetrahydrofuran, toluene, xylene, mesitylene,
tetralin, decalin and n-butylbenzene. The concentration of a
polymer compound varies depending upon the structure and molecular
weight of the polymer compound; however, the polymer compound may
be dissolved in these solvents in a concentration of 0.1 wt % or
more.
[0285] Next, a method of producing a polymer compound according to
the present invention will be explained.
[0286] A polymer compound according to the present invention can be
produced by using a compound represented by Y.sub.1-A-Y.sub.2 as
one of the raw materials and subjecting the raw materials to
condensation polymerization.
[0287] In the formula, A has a functional side chain containing at
least one functional group selected from the group consisting of a
hole injection/transport group containing at least one hetero atom
other than a nitrogen atom or at least two nitrogen atoms, an
electron injection/transport group containing at least one hetero
atom other than a nitrogen atom or at least two nitrogen atoms, and
a light emitting group containing a condensed polycyclic aromatic
hydrocarbon or a heterocyclic ring; the functional group directly
bonded to a saturated carbon of a fluorenediyl group or bonded to
the fluorenediyl group via --R.sub.k--X-- (R.sub.k represents an
alkylene group and X represents a direct bond or bonding group) at
X, that is, represents a fluorenediyl group that may be
substituted.
[0288] Y.sub.1 and Y.sub.2 each independently represent a
condensation-polymerizable substituent.
[0289] Furthermore, when a polymer compound according to the
present invention has a repeat unit except -A-, condensation
polymerization may be performed in the presence of a compound,
which serves as a repeat unit except -A- and has two substituents
involved in condensation polymerization.
[0290] As the compound having two substituents involved in
condensation polymerization and serving as a repeat unit except the
repeat unit represented by -A-, for example, mention may be made of
a compound represented by Y.sub.3--Ar.sub.1-Y.sub.4 (where Ar.sub.1
is the same as defined above, Y.sub.3 and Y.sub.4 each
independently represent a substituent involved in condensation
polymerization.
[0291] A polymer compound according to the present invention can be
produced by subjecting a compound represented by
Y.sub.3--Ar.sub.1-Y.sub.4 in addition to a compound represented by
Y.sub.1-A-Y.sub.2 to condensation polymerization.
[0292] As a compound serving as a repeat unit except the repeat
unit represented by the aforementioned formula (1) and having two
substituents corresponding to the aforementioned formula (13) and
involved in condensation polymerization, a compound represented by
the following formula (14) may be mentioned.
##STR00115##
where the definitions and preferable examples of Ar.sub.4,
Ar.sub.5, Ar.sub.6, Ar.sub.7, Ar.sub.8, Ar.sub.9, Ar.sub.10, o and
p are the same as mentioned above; and Y.sub.5 and Y.sub.6 each
independently represent a substituent involved in condensation
polymerization.
[0293] In a production method according to the present invention,
examples of the substituent involved in condensation polymerization
include a halogen atom, alkylsulfonate group, arylsulfonate group,
arylalkylsulfonate group, boric acid ester group, sulfonium-methyl
group, phosphonium-methyl group, phosphonate-methyl group,
monohalogenated methyl group, --B(OH), formyl group, cyano group
and vinyl group.
[0294] Examples of the halogen atom herein include a fluorine atom,
chlorine atom, bromine atom and iodine atom.
[0295] Examples of the alkylsulfonate group include a
methanesulfonate group, ethanesulfonate group and
trifluoromethanesulfonate group. Examples of the arylsulfonate
group include a benzenesulfonate group and p-toluenesulfonate
group. Examples of the arylsulfonate group include a
benzylsulfonate group.
[0296] Examples of the boric acid ester group include the groups
represented by the following formulas.
##STR00116##
where Me represents a methyl group and Et represents an ethyl
group.
[0297] Examples of the sulfonium-methyl group include the groups
represented by the following formulas.
--CH.sub.2S.sup.+Me.sub.2X.sup.-,--CH.sub.2S.sup.+Ph.sub.2X.sup.-
where X represents a halogen atom and Ph represents a phenyl
group.
[0298] Examples of the phosphonium-methyl group include the groups
represented by the following formula.
--CH.sub.2P.sup.+Ph.sub.3X.sup.-,
where X represents a halogen atom.
[0299] Examples of the phosphonate-methyl group include the groups
represented by the following formula.
--CH.sub.2PO(OR').sub.2,
where X represents a halogen atom, R' represents an alkyl group,
aryl group or arylalkyl group.
[0300] Examples of the monohalogenated-methyl group include a
methyl fluoride group, methyl chloride group, methyl bromide group
and methyl iodide group.
[0301] A preferable substituent as the substituent involved in
condensation polymerization varies depending upon the type of
polymerization reaction. For example, in a reaction such as the
Yamamoto coupling reaction using a nickel(0) complex, a halogen
atom, alkylsulfonate group, arylsulfonate group or an
arylalkylsulfonate group may be mentioned. In a reaction such as
the Suzuki coupling reaction using a nickel catalyst or a palladium
catalyst, an alkylsulfonate group, halogen atom, boric acid ester
group or --B(OH).sub.2 may be mentioned.
[0302] More specifically, a production method according to the
present invention can be carried out by using a compound, which has
a plurality of substituents involved in condensation polymerization
and serves as a monomer, if necessary, dissolved in an organic
solvent, in the presence of an alkali or an appropriate catalyst,
at a temperature from the melting point to the boiling point (both
inclusive) of the organic solvent, for example, in accordance with
a known method described in publications such as
[0303] "Organic Reactions", Vol. No. 14, p. 270-490, John Wiley
& Sons, Inc., (1965);
[0304] Organic Syntheses", Collective Volume VI, p. 407-411, John
Wiley & Sons, Inc, (1988);
[0305] Chem. Rev., Vol. No. 95, p. 2457 (1995);
[0306] J. Organomet. Chem., Vol. No. 576, p. 147 (1999); and
[0307] Makromol. Chem., Macromol. Symp., Vol. No. 12, p. 229
(1987).
[0308] In a method of producing a polymer compound according to the
present invention, a known condensation reaction may be used in
accordance with the substituent involved in condensation
polymerization.
[0309] For example, mention may be made of a method of polymerizing
corresponding monomers by the Suzuki coupling reaction, a
polymerization method by the Grignard reaction, a polymerization
method using an Ni(O) complex, a polymerization method using an
oxidization agent such as FeCl.sub.3, an electrochemical
oxidization polymerization method, and polymerization by a method
of decomposing an intermediate polymer having an appropriate
leaving group.
[0310] Of them, a polymerization method by the Suzuki coupling
reaction, a polymerization method by the Grignard reaction, a
polymerization method using a Ni(O) complex are preferable since
structure control can be readily made.
[0311] Of the production methods of the present invention, mention
may be preferably made of a method in which substituents (Y.sub.1,
Y.sub.2, Y.sub.3, Y.sub.4, Y.sub.5 and Y.sub.6) involved in
condensation polymerization are each independently selected from
the group consisting of a halogen atom, alkylsulfonate group,
arylsulfonate group, and arylalkylsulfonate group and subjected to
condensation and polymerization in the presence of a Ni(O)
complex.
[0312] Examples of the raw material compound include
[0313] a dihalogenated compound, bis(alkylsulfonate) compound,
bis(arylsulfonate) compound, bis(arylalkyl sulfonate) compound,
halogen-alkylsulfonate compound, halogen-arylsulfonate compound,
halogen-arylalkylsulfonate compound, alkylsulfonate-arylsulfonate
compound, alkylsulfonate-arylalkylsulfonate compound, and
alkylsulfonate-arylalkylsulfonate compound.
[0314] In this case, mention may be made of a method of producing a
polymer compound controlled in sequence by use of, as a raw
material, halogen-alkylsulfonate compound, halogen-arylsulfonate
compound, halogen-arylalkylsulfonate compound,
arylalkylsulfonate-arylsulfonate compound,
alkylsulfonate-arylalkylsulfonate compound, or
arylsulfonate-arylalkylsulfonate compound.
[0315] Of the production methods of the preset invention, mention
is preferably made of a method in which substituents (Y.sub.1,
Y.sub.2, Y.sub.3, Y.sub.4, Y.sub.5 and Y.sub.6) involved in
condensation polymerization are each independently selected from
the group consisting of a halogen atom, alkylsulfonate group,
arylsulfonate group, arylalkylsulfonate group, boric acid group and
boric acid ester group and subjected to condensation and
polymerization in the presence of a Ni catalyst or a palladium
catalyst such that the ratio of the total mole number (J) of the
halogen atom, alkylsulfonate group, arylsulfonate group and
arylalkylsulfonate group contained in the all raw material
compounds relative to the total mole number (K) of the boric acid
(--B(OH).sub.2) group and boric acid ester group substantially
becomes substantially 1 (K/J generally falls within the range of
0.7 to 1.2).
[0316] Examples of specific combination of raw materials include
combinations of a dihalogenated compound, bis(alkylsulfonate)
compound, bis(arylsulfonate) compound or bis(arylalkyl sulfonate)
compound, and a diboric acid compound or diboric acid ester
compound.
[0317] Furthermore, mention may be made of a halogen-boric acid
compound, halogen-boric acid ester compound, alkylsulfonate-boric
acid compound, alkylsulfonate-boric acid ester compound,
arylsulfonate-boric acid compound, arylsulfonate-boric acid ester
compound, arylalkylsulfonate-boric acid compound,
arylalkylsulfonate-boric acid compound, and
arylalkylsulfonate-boric acid ester compound.
[0318] In this case, mention may be made of a method of producing a
polymer compound controlled in sequence by use of, as raw
materials, a halogen-boric acid compound, halogen-boric acid ester
compound, alkylsulfonate-boric acid compound, alkylsulfonate-boric
acid ester compound, arylsulfonate-boric acid compound,
arylsulfonate-boric acid ester compound, arylalkylsulfonate-boric
acid compound, arylalkylsulfonate-boric acid compound or
arylalkylsulfonate-boric acid ester compound.
[0319] The organic solvent herein varies depending upon the
compounds and the reaction to be used. Generally, in order to
suppress a side reaction, deoxidization treatment is sufficiently
applied to the solvent to be used and the reaction is preferable
performed under an inert atmosphere. Also, similarly, dewater
treatment is preferably applied. However, this is not applied to
the case where a reaction is performed in a binary phase of water
and a solvent such as in Suzuki coupling reaction.
[0320] Examples of the solvent include
[0321] saturated hydrocarbons such as pentane, hexane, heptane,
octane and cyclohexane;
[0322] unsaturated hydrocarbons such as benzene, toluene, ethyl
benzene and xylene;
[0323] halogenated saturated hydrocarbons such as carbon
tetrachloride, chloroform, dichloromethane, chlorobutane,
bromobutane, chloropentane, bromopentane, chlorohexane,
bromohexane, chlorocyclohexane and bromocyclohexane;
[0324] halogenated unsaturated hydrocarbons such as chlorobenzene,
dichlorobenzene and trichlorobenzene;
[0325] alcohols such as methanol, ethanol, propanol, isopropanol,
butanol and t-butyl alcohol;
[0326] carboxylic acids such as formic acid, acetic acid and
propionic acid;
[0327] ethers such as dimethyl ether, diethyl ether, methyl-t-butyl
ether, tetrahydrofuran, tetrahydropyran and dioxane;
[0328] amines such as trimethylamine, triethylamine,
N,N,N',N'-tetramethylethylenediamine and pyridine; and
[0329] amides such as N,N-dimethylformamide, N,N-dimethylacetamide,
N,N-diethylacetamide, and N-methylmorpholine oxide. These solvents
may be used singly or in a mixture. Of them, ethers are preferable,
and tetrahydrofuran and diethyl ether are further preferable.
[0330] To perform a reaction, an alkali and a suitable catalyst may
be appropriately added. They may be selected depending upon the
reaction to be employed. The alkali or catalyst is preferably
dissolved sufficiently in the solvent to be used. As a method for
blending the alkali or catalyst, mention may be made of a method of
adding an alkali or catalyst to a reaction solution while gently
stirring the reaction solution under an inert atmosphere such as
argon and nitrogen and a method of gently adding, conversely, a
reaction solution to a solution of an alkali or catalyst.
[0331] When a polymer compound according to the present invention
is employed in, for example, a polymer LED, since the purity of the
polymer compound has an effect upon the performance of the device
such as light emission property, it is preferable that before
subjecting to polymerization, a monomer is purified by a method
such as distillation, sublimation purification, or
recrystallization and thereafter subjected to polymerization.
Furthermore, after polymerization, purification treatment such as
precipitation purification or fractionation by chromatography is
preferably performed.
[0332] Next, application of a polymer compound according to the
present invention will be explained.
[0333] The polymer compound of the present invention generally
emits fluorescence or phosphorescence in a solid state and can be
used as a polymer light-emitting material (light emission material
of a high molecular weight).
[0334] The polymer compound has an excellent charge
transportability and suitably used as a polymer LED material and as
a charge transport material. The polymer LED using the polymer
light-emitting material is a high performance polymer LED capable
of being driven at a low voltage with high efficiency. Therefore,
the polymer LED can be used as curved and planar light sources for
backlight or illumination of liquid crystal displays and used in
devices such as a segment type display device and a flat panel
display of dot matrix.
[0335] Furthermore, the polymer compound of the present invention
may be used as a laser dye, a material for an organic solar
battery, organic semiconductor for an organic transistor and a
material for a electrically conductive thin film such as an
electrically conductive thin film or organic semiconductor thin
film.
[0336] Moreover, the polymer compound of the present invention can
be used as a material for a light-emitting thin film emitting
fluorescence or phosphorescence.
[0337] Next, a polymer LED according to the present invention will
be explained.
[0338] The polymer LED of the present invention is characterized by
having an organic layer, which is positioned between the electrodes
consisting of an anode and a cathode and contains a polymer
compound according to the present invention.
[0339] The organic layer may be any one of a light-emitting layer,
hole transport layer, hole injecting layer, electron transport
layer, electron injection layer and interlayer; however, the
organic layer is preferably a light-emitting layer.
[0340] The light-emitting layer herein refers to a layer having a
function of emitting light. The hole transport layer refers to a
layer having a function of transporting holes. The electron
transport layer refers to a layer having a function of transporting
electrons. Furthermore, the interlayer refers to a layer positioned
between the light-emitting layer and the cathode and adjacent to
the light-emitting layer and playing a role of isolating the
light-emitting layer from the cathode or light-emitting layer from
the hole injection layer or the hole transport layer. Not that the
electron transport layer and hole transport layer are collectively
referred to as a charge transport layer. Furthermore, the electron
injection layer and hole injection layer are collectively referred
to as a charge injection layer. The light-emitting layer, hole
transport layer, hole injection layer, electron transport layer,
and electron injection layer each independently consisting of two
or more layers may be used.
[0341] When an organic layer serves as a light-emitting layer, the
light-emitting layer consisting of the organic layer may further
contain a hole transportable material, an electron transportable
material or a light-emitting material. The light-emitting material
herein refers to a material emitting fluorescence and/or
phosphorescence.
[0342] When a polymer compound according to the present invention
is mixed with a hole transportable material, the mixing ratio of
the hole transportable material relative to the total mixture is 1
wt % to 80 wt %, and preferably 5 wt % to 60 wt %.
[0343] When a polymer material according to the present invention
is mixed with an electron transportable material, the mixing ratio
of the electron transportable material relative to the total
mixture is 1 wt % to 80 wt %, and preferably, 5 wt % to 60 wt
%.
[0344] When a polymer compound according to the present invention
is mixed with a light-emitting material, the mixing ratio of the
light-emitting material relative to the total mixture is 1 wt % to
80 wt %, and preferably, 5 wt % to 60 wt %.
[0345] When a polymer compound according to the present invention
is mixed with a light-emitting material, hole transportable
material and/or electron transportable material, the mixing ratio
of the light-emitting material relative to the total mixture is 1
wt % to 50 wt %, and preferably, 5 wt % to 40 wt %; and the ratio
of the hole transportable material plus electron transportable
material is 1 wt % to 50 wt %, and preferably, 5 wt % to 40 wt %.
Therefore, the content of the polymer compound of the present
invention is 98 wt % to 1 wt %, and preferably, 90 wt % to 20 wt
%.
[0346] As the hole transportable material, electron transportable
material and light-emitting material, a known low molecular weight
compound, triplet light-emitting complex or polymer compound may be
used; however, a polymer compound is preferably used.
[0347] As the polymer hole transportable material, electron
transportable material and light-emitting material, mention may be
made of a polyfluorene and a derivative and copolymer thereof; a
polyarylene and a derivative and copolymer thereof; a
polyarylenevinylene and a derivative and copolymer thereof; and a
copolymer of an aromatic amine and a derivative thereof, which are
disclosed, for example, in WO99/13692, WO99/48160, GB2340304A,
WO00/53656, WO01/19834, WO00/55927, GB2348316, WO00/46321,
WO00/06665, WO99/54943, WO99/54385, U.S. Pat. No. 5,777,070,
WO98/06773, WO97/05184, WO00/35987, WO00/53655, WO01/34722,
WO99/24526, WO00/22027, WO00/22026, WO98/27136, US573636,
WO98/21262, U.S. Pat. No. 5,741,921, WO97/09394, WO96/29356,
WO96/10617, EP0707020, WO95/07955, JP-A-2001-181618,
JP-A-2001-123156, JP-A-2001-3045, JP-A-2000-351967,
JP-A-2000-303066, JP-A-2000-299189, JP-A-2000-252065,
JP-A-2000-136379, JP-A-2000-104057, JP-A-2000-80167,
JP-A-10-324870, JP-A-10-114891, JP-A-9-111233 and JP-A-9-45478.
[0348] As a fluorescent material of a low molecular weight
compound, use may be made of a naphthalene derivative, anthracene
or a derivative thereof; perylene or a derivative thereof; a dye
such as polymethine base, xanthene base, coumarin base or cyanine
base dye, a metallic complex of 8-hydroxyquinoline or a derivative
thereof; aromatic amine; tetraphenylcyclopentadiene or a derivative
thereof; or tetraphenylbutadiene or a derivative thereof.
[0349] More specifically, known compounds, for example, described
in JP-A-57-51781 and 59-194393 may be used.
[0350] Examples of the triplet light-emitting complex include
Ir(ppy).sub.3 Btp.sub.2Ir(acac) containing iridium as a core metal,
PtOEP containing platinum as a core metal and Eu(TTA).sub.3phen
containing europium as a core metal.
##STR00117## ##STR00118##
[0351] Specific examples of the triplet light-emitting complex are
described, for example, in Nature, (1998), 395, 151; Appl. Phys.
Lett. (1999), 75(1), 4; Proc. SPIE-lnt. Soc. Opt. Eng. (2001), 4105
(Organic Light-emitting Materials and Devices IV), 119; J. Am.
Chem. Soc., (2001), 123, 4304; Appl Phys. Lett., (1997), 71 (18),
2596; Syn, Met., (1998), 94(1), 103; Syn. Met., (1999), 99 (2),
1361; Adv. Mater., (1999), 11(10), 852; and Jpn. J. Appl. Phys.,
34, 1883 (1995).
[0352] A composition according to the present invention contains at
least one type of material selected from a hole transportable
material, electron transportable material and light-emitting
material and a polymer compound according to the present invention
and is used as a light-emitting material or a charge transport
material.
[0353] The content ratio of at least one type of material selected
from a hole transportable material, electron transportable material
and light-emitting material as mentioned above relative to the
polymer compound of the present invention may be determined
depending upon the application; however, when the composition is as
a light-emitting material, the content ratio is preferably the same
as in the light-emitting layer.
[0354] A mixture of two or more polymer compounds according to the
present invention can be used as a composition. To enhance the
property (performance) of a polymer LED, the composition preferably
contains two or more types of polymers selected from the group
[0355] consisting of a polymer compound containing a hole
injection/transport group at a side chain,
[0356] a polymer compound containing an electron
injection/transport group at a side chain, and
[0357] a polymer compound containing a light-emitting group at a
side chain.
[0358] In a light-emitting layer that the polymer LED of the
present invention has, the optimal value of film thickness differs
depending upon the material to be used and may be selected so as to
have appropriate driving voltage value and light emission
efficiency value. The film thickness is, for example, 1 nm to 1
.mu.m, preferably 2 nm to 500 nm, and further preferably, 5 nm to
200 nm.
[0359] Examples of a method for forming the light-emitting layer
include a method of forming a film from a solution. Examples of the
method of forming a film from a solution include coating methods
such as spin-coating method, casting method, microgravure coating
method, gravure-coating method, bar-coating method, roll-coating
method, wire-bar coating method, dip-coating method, spray-coating
method, screen printing method, flexographic printing method,
offset printing method, and inkjet printing method. In view of ease
of pattern formation and multicolor coating, printing methods such
as a screen printing method, flexographic printing method, offset
printing method, and inkjet printing method are preferable.
[0360] As the ink composition to be used in printing methods, any
composition may be used as long as at least one type of polymer
compound according to the present invention is contained. The
composition may contain a hole transportable material, electron
transportable material, light-emitting material, solvent and
additives such as a stabilizer may be contained other than a
polymer compound according to the present invention.
[0361] The ratio of the polymer compound according to the present
invention in the ink composition is generally 20 wt % to 100 wt %
based on the total weight of the composition excluding a solvent
and preferably 40 wt % to 100 wt %.
[0362] Furthermore, when a solvent is contained in an ink
composition, the ratio of the solvent is generally 1 wt % to 99.9
wt % based on the total weight of the composition, preferably 60 wt
% to 99.5 wt % and more preferably, 80 wt % to 99.0 wt %.
[0363] The viscosity of the ink composition varies depending upon
the printing method. When the ink composition passes through an
ejection apparatus in the case of inkjet printing method, the
viscosity preferably falls within the range of 1 to 20 mPas at
25.degree. C. in order to prevent clogging and bending at the time
of ejection.
[0364] The solution of the present invention may contain additives
for controlling viscosity and/or surface tension other than a
polymer compound according to the present invention. Examples of
the additives include a polymer compound (thickner) of a high
molecular weight and a poor solvent for increasing viscosity, a
polymer compound of a low molecular weight for reducing viscosity,
and a surfactant for reducing surface tension may be used in an
appropriate combination.
[0365] As the polymer compound of a high molecular weight, any
polymer may be used as long as it is soluble in the same solvent as
that of a polymer compound according to the present invention and
as long as it does not inhibit light emission and charge transport.
For example, polystyrene and polymethyl methacrylate of a high
molecular weight or a polymer compound having a larger molecular
weight of the polymer compounds of the present invention can be
used. The weight average molecular weight is preferably 0.5 million
or more and more preferably 1 million or more.
[0366] A poor solvent can be used as a thickner. More specifically,
viscosity can be increased by adding a small amount of poor solvent
for the solid matter of the solution. When a poor solvent is added
for this purpose, any type and addition amount of the solvent may
be used as long as the solid matter of the solution does not
precipitate. In consideration of the stability during storage, the
amount of the poor solvent is preferably 50 wt % or less relative
to the total amount of the solvent and further preferably 30 wt %
or less.
[0367] A solution according to the present invention may contain an
antioxidant other than a polymer compound according to the present
invention to improve storage stability. As the antioxidant, any
antioxidant may be used as long as it is soluble in the same
solvent for a polymer compound according to the present invention
and it does not inhibit light emission or charge transport. For
example, mention may be made of a phenol based antioxidant and a
phosphorus based antioxidant.
[0368] When a solution according to the present invention is used
as an ink composition, the solvent to be used may not be
particularly limited; however, mention is preferably made of a
solvent capable of dissolving or homogeneously dispersing
components of the ink composition except for the solvent. Examples
of the solvent include
[0369] chlorine base solvents such as chloroform, methane chloride,
1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene and
o-dichlorobenzene;
[0370] ether base solvents such as tetrahydrofuran, dioxane and
anisole;
[0371] aromatic hydrocarbon base solvents such as toluene and
xylene;
[0372] aliphatic hydrocarbon base solvents such as cyclohexane;
methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane,
n-nonane and n-decane;
[0373] ketone base solvents such as acetone, methylethyl ketone,
cyclohexanone, benzophenone and acetophenone;
[0374] ester solvents such as ethyl acetate, butyl acetate,
ethyl-cellosolve acetate, methyl benzoate and phenyl acetate;
[0375] polyhydric alcohols such as ethylene glycol, ethylene glycol
monobutyl ether, ethylene glycol monoethyl ether, ethylene glycol
monomethyl ether, dimethoxyethane, propylene glycol,
diethoxymethane, triethylene glycol monoethyl ether, glycerin, and
1,2-hexane diol, and derivatives of these;
[0376] alcohol base solvents such as methanol, ethanol, propanol,
isopropanol and cyclohexanol;
[0377] sulfoxide base solvents such as dimethylsulfoxide; and
[0378] amide base solvents such as N-methyl-2-pyrrolidone and
N,N-dimethylformamide.
[0379] These solvent may be used singly or in a combination of
theses.
[0380] Of them, in view of solubility, homogeneity during film
formation time and viscosity property of a polymer compound and the
like, use is preferably made of the aromatic hydrocarbon base
solvent, aliphatic hydrocarbon base solvent, ester base solvent and
ketone base solvent; and more preferably, toluene, xylene, ethyl
benzene, diethylbenzene, trimethylbenzene, n-propylbenzene,
isopropylbenzene, n-butylbenzene, isobutylbenzene, s-butylbenzene,
anisole, ethoxy benzene, 1-methylnaphthalene, cyclohexane,
cyclohexanone, cyclohexylbenzene, bicyclohexyl,
cyclohexenyl-cyclohexanone, n-heptyl-cyclohexane,
n-hexyl-cyclohexane, 2-propyl-cyclohexanon, 2-heptanon, 3-heptanon,
4-heptanon, 2-octanone, 2-nonanone, 2-decanone, dicyclohexyl
ketone, acetophenone and benzophenone.
[0381] As the number of types of solvents of the solution, in view
of film formability, device characteristics etc., two or more types
of solvents are preferable, 2 to 3 types of solvents are more
preferable, and 2 types of solvents are further preferable.
[0382] When 2 types of solvents are contained in the solution, one
of them may be present in a solid state at 25.degree. C. In view of
film formability, one of the solvent preferably has a boiling point
of 180.degree. C. or more and more preferably 200.degree. C. or
more. In view of viscosity, both types of solvents preferably
dissolve 1 wt % or more of aromatic polymer at 60.degree. C. and
one of the two types of solvents may dissolve 1 wt % or more of
aromatic polymer at 25.degree. C.
[0383] When 2 types of solvents are contained in the solution, in
view of viscosity and film formability, the solvent having the
highest boiling point is contained in an amount of 40 to 90 wt %
based on the total weight of the solvents in the solution, more
preferably 50 to 90 wt %, and further preferably, 65 to 85 wt
%.
[0384] The number of types of polymer compounds according to the
present invention contained in a solution can be one or two or
more. A polymer compound other than a polymer compound according to
the present invention may be contained as long as it cannot damage
device property, etc.
[0385] The solution of the present invention may contain water and
a metal and a salt thereof in the rage of 1 to 1000 ppm. Examples
of the metal include lithium, sodium, calcium, potassium, iron,
copper, nickel, aluminum, zinc, chrome, manganese, cobalt, platinum
and iridium. In addition, silicon, phosphorus, fluorine, chlorine,
and bromine may be contained within the range of 1 to 1000 ppm.
[0386] A thin film can be produced by use of a solution according
to the present invention in accordance with a spin-coating method,
casting method, microgravure coating method, gravure-coating
method, bar-coating method, roll-coating method, wire-bar coating
method, dip-coating method, spray-coating method, screen printing
method, flexographic printing method, offset printing method,
inkjet printing method, or the like. Of them, the solution of the
present invention is preferably used when a film is formed by a
screen printing method, flexographic printing method, offset
printing method, or inkjet printing method, and more preferably by
an inkjet printing method.
[0387] Examples of the thin film to be prepared by use of a
solution according to the present invention include a
light-emitting thin film, electrically conductive thin film and
organic semiconductor thin film.
[0388] The electrically conductive thin film of the present
invention preferably has a surface resistance of 1
K.OMEGA./.quadrature. or less. The electric conductivity of the
thin film can be improved by doping a Lewis acid, an ionic compound
and the like. The surface resistance is more preferably 100
K.OMEGA./.quadrature. or less, and further preferably, 10
K.OMEGA./.quadrature..
[0389] In the organic semiconductor thin film of the present
invention, the value of larger one of an electron mobility and hole
mobility is preferably not less than 10.sup.-5 cm.sup.2/V/second,
more preferably, not less than 10.sup.-3 cm.sup.2/V/second, and
further preferably, not less than 10.sup.-1 cm.sup.2/V/second.
[0390] An organic transistor can be formed by forming the organic
semiconductor thin film on a Si substrate having an insulating film
formed of e.g., SiO.sub.2 and a gate electrode formed therein and
forming a source electrode and a drain electrode of Au or the
like.
[0391] Furthermore, examples of a polymer LED according to the
present invention include
[0392] a polymer LED formed by providing an electron transport
layer between an cathode and a light-emitting layer;
[0393] a polymer LED formed by providing a hole transport layer
between an anode and a light-emitting layer; and
[0394] a polymer LED formed by providing an electron transport
layer between an cathode and a light-emitting layer and a hole
transport layer between the anode and the light-emitting layer.
[0395] For example, the following structures a) to d) are
specifically mentioned.
[0396] a) anode/light-emitting layer/cathode
[0397] b) anode/hole transport layer/light-emitting
layer/cathode
[0398] c) anode/light-emitting layer/electron transport
layer/cathode
[0399] d) anode/hole transport layer/light-emitting layer/electron
transport layer/cathode
[0400] (where the mark "/" means that individual layers are stacked
in adjacent to each other.
[0401] Furthermore, in each of the structures, an interlayer may be
provided between the light-emitting layer and the anode in adjacent
to the light-emitting layer.
[0402] To describe more specifically,
[0403] a') anode/interlayer/light-emitting layer/cathode
[0404] b') anode/hole transport layer/interlayer/light-emitting
layer/cathode
[0405] c') anode/interlayer/light-emitting layer/electron transport
layer/cathode
[0406] d') anode/hole transport layer/interlayer/light-emitting
layer/electron transport layer/cathode
[0407] When a polymer LED according to the present invention has a
hole transport layer, examples of the hole transportable material
to be employed include polyvinylcarbazole or a derivative thereof;
polysilane or a derivative thereof; polysiloxane derivative having
an aromatic amine in a side chain or the main chain; pyrazoline
derivative; arylamine derivative; stilbene derivative;
triphenyl-diamine derivative; polyaniline or a derivative thereof;
polythiophene or a derivative thereof; polypyrrole or a derivative
thereof; poly(p-phenylenevinylene) or a derivative thereof; and
poly(2,5-thienylenevinylene) or a derivative thereof.
[0408] Specific examples of the hole transportable material include
those described in JP-A-63-70257, JP-A-63-175860, JP-A-2-135359,
JP-A-2-135361, JP-A-2-209988, JP-A-3-37992, and JP-A-3-152184.
[0409] Of them, as a hole transportable material for use in hole
transport layer, mention may be preferably made of polymer hole
transportable materials such as polyvinylcarbazole or a derivative
thereof, polysilane or a derivative thereof, a polysiloxane
derivative having an aromatic amine compound group in a side chain
or the main chain, polyaniline or a derivative thereof,
polythiophene or a derivative thereof, poly(p-phenylenevinylene) or
a derivative thereof, and poly(2,5-thienylenevinylene) or a
derivative thereof; and more preferably, polyvinylcarbazole or a
derivative thereof, polysilane or a derivative thereof, and a
polysiloxane derivative having an aromatic amine in a side chain or
the main chain.
[0410] Examples of a hole transportable material of a low molecular
compound include a pyrazoline derivative, arylamine derivative,
stilbene derivative and triphenyl diamine derivative. The hole
transportable material of a low molecular compound is preferably
used by dispersing it in a polymer binder.
[0411] As the polymer binder to be mixed, it is preferred to use
one which does not inhibit charge transfer extremely. Furthermore,
it is suitable to use one having no intensive absorption to visible
light. Example of the polymer binder include
poly(N-vinylcarbazole), polyaniline or a derivative thereof,
polythiophene or a derivative thereof, poly(p-phenylenevinylene) or
a derivative thereof, poly(2,5-thienylenevinylene) or a derivative
thereof, polycarbonate, polyacrylate, polymethylacrylate,
polymethylmethacrylate, polystyrene, polyvinylchloride and
polysiloxane.
[0412] Poly(N-vinylcarbazole) or a derivative thereof can be
obtained from a vinyl monomer through cation polymerization or
radical polymerization.
[0413] Examples of polysilane or a derivative thereof include
compounds described in Chem. Rev. Vol. No. 89, p. 1359 (1989) and
the published specification of British Patent GB2300196. As a
synthetic method thereof, the method described in these documents
can be used. In particular, the Kipping method can be suitably
used.
[0414] In polysiloxane or a derivative thereof, since a
polysiloxane skeleton structure has no hole transportability, one
having the aforementioned structure of a low molecular weight hole
transportable material in a side chain or the main chain is
suitably used. In particular, one having a hole transportable
aromatic amine in a side chain or the main chain may be
mentioned.
[0415] A method of forming a hole transfer layer film is not
particularly limited. In the case of low molecular weight hole
transportable material, a method of forming a film from a mixed
solution with a polymer binder may be mentioned. In the case of a
high molecular weight hole transportable material, a method of
forming a film from a solution may be mentioned.
[0416] As a solvent for use in film-formation from a solution, one
that can dissolve or homogenously disperse a hole transportable
material is preferable. Examples of the solvent include
[0417] chlorine base solvents such as chloroform, methane chloride,
1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene and
o-dichlorobenzene;
[0418] ether base solvents such as tetrahydrofuran and dioxane;
[0419] aromatic hydrocarbon base solvents such as toluene and
xylene;
[0420] aliphatic hydrocarbon base solvents such as cyclohexane;
methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane,
n-nonane and n-decane;
[0421] ketone base solvents such as acetone, methylethyl ketone and
cyclohexanone;
[0422] ester solvents such as ethyl acetate, butyl acetate and
ethylcellosolve acetate;
[0423] polyhydric alcohols such as ethylene glycol, ethylene glycol
monobutyl ether, ethylene glycol monoethyl ether, ethylene glycol
monomethyl ether, dimethoxyethane, propylene glycol,
diethoxymethane, triethylene glycol monoethyl ether, glycerin and
1,2-hexane diol, and derivatives of these;
[0424] alcohol base solvents such as methanol, ethanol, propanol,
isopropanol and cyclohexanol;
[0425] sulfoxide base solvents such as dimethylsulfoxide; and
[0426] amide base solvents such as N-methyl-2-pyrrolidone and
N,N-dimethylformamide.
[0427] These solvent may be used singly or in combination.
[0428] Examples of the film formation method from a solution
include a spin-coating method, casting method, microgravure coating
method, gravure-coating method, bar-coating method, roll-coating
method, wire-bar coating method, dip-coating method, spray-coating
method, screen printing method, flexographic printing method,
offset printing method and inkjet printing method.
[0429] As the film thickness of a hole transport layer, its optimal
value varies depending upon the material to be used. The film
thickness may be selected such that driving voltage and light
emission efficiency take appropriately values. However, it is at
least required to have a sufficient film thickness not to produce
pin holes. The extremely thick film is not preferable because the
driving voltage of the device increases. Accordingly, the film
thickness of the hole transport layer is, for example, from 1 nm to
1 .mu.m, preferably 2 nm to 500 nm, and further preferably, 5 nm to
200 nm.
[0430] When a polymer LED according to the present invention has an
electron transport layer, as the electron transportable material to
be used, a known material may be used. Examples thereof include
[0431] a metal complex of oxadiazole derivative thereof;
[0432] anthraquinodimethane derivative thereof,
[0433] benzoquinone or a derivative thereof,
[0434] naphthoquinone or a derivative thereof,
[0435] anthraquinone or a derivative thereof,
[0436] tetracyanoanthraquino-dimethane or a derivative thereof,
[0437] fluorenone derivative,
[0438] diphenyl-dicyanoethylene or a derivative thereof;
[0439] diphenoquinone derivative, or
[0440] 8-hydroxyquinoline or a derivative thereof;
[0441] polyquinoline or a derivative thereof;
[0442] polyquinoxaline or a derivative thereof; and
[0443] polyfluorene or a derivative thereof.
[0444] Specific examples include those described in JP-A-63-70257,
JP-A-63-175860, JP-A-2-135359, JP-A-2-135361, JP-A-2-209988,
JP-A-3-37992 and JP-A-3-152184.
[0445] Of them, mention is preferably made of a metal complex of
oxadiazole derivative thereof,
[0446] benzoquinone or a derivative thereof,
[0447] anthraquinone or a derivative thereof, or
[0448] 8-hydroxyquinoline or a derivative thereof;
[0449] polyquinoline or a derivative thereof;
[0450] polyquinoxaline or a derivative thereof; and
[0451] polyfluorene or a derivative thereof, and further
preferably,
[0452] 2-(4-viphenyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole,
benzoquinone, anthraquinone, tris(8-quinolyl)aluminum and
polyquinoline.
[0453] A film formation method for an electron transport layer is
not particularly limited. Examples of a film formation method using
a low molecular weight electron transportable material include a
vacuum deposition method for forming a film from powder and a
method for forming a film from a solution or molten state. Examples
of a film formation method using a high molecular weight electron
transportable material include a method of forming a film from a
solution or molten state. In the method of forming a film from a
solution or molten state, a polymer binder as mentioned above may
be used together.
[0454] As a solvent to be used in forming a film from a solution,
one capable of dissolving or homogeneously dispersing an electron
transportable material and/or a polymer binder is preferable.
Examples of the solvent include
[0455] chlorine base solvents such as chloroform, methane chloride,
1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene and
o-dichlorobenzene;
[0456] ether base solvents such as tetrahydrofuran and dioxane;
[0457] aromatic hydrocarbon base solvents such as toluene and
xylene;
[0458] aliphatic hydrocarbon base solvents such as cyclohexane;
methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane,
n-nonane and n-decane;
[0459] ketone base solvents such as acetone, methylethyl ketone and
cyclohexanone;
[0460] ester solvents such as ethyl acetate, butyl acetate and
ethyl-cellosolve acetate;
[0461] polyhydric alcohols such as ethylene glycol, ethylene glycol
monobutyl ether, ethylene glycol monoethyl ether, ethylene glycol
monomethyl ether, dimethoxyethane, propylene glycol,
diethoxymethane, triethylene glycol monoethyl ether, glycerin and
1,2-hexane diol, and derivatives of these;
[0462] alcohol base solvents such as methanol, ethanol, propanol,
isopropanol and cyclohexanol;
[0463] sulfoxide base solvents such as dimethylsulfoxide; and
[0464] amide base solvents such as N-methyl-2-pyrrolidone and
N,N-dimethylformamide.
[0465] These solvent may be used singly or in combination.
[0466] As a method of forming a film from a solution or a molten
state, use may be made of coating methods such as a spin-coating
method, casting method, microgravure coating method,
gravure-coating method, bar-coating method, roll-coating method,
wire-bar coating method, dip-coating method, spray-coating method,
screen printing method, flexographic printing method, offset
printing method and inkjet printing method.
[0467] As the film thickness of an electron transport layer, its
optimal value varies depending upon the material to be used. The
film thickness may be selected such that driving voltage and light
emission efficiency take appropriately values. However, it is at
least required to have a sufficient film thickness not to produce
pin holes. The extremely thick film is not preferable because the
driving voltage of the device increases. Accordingly, the film
thickness of the electron transport layer is, for example, from 1
nm to 1 .mu.m, preferably 2 nm to 500 nm, and further preferably, 5
nm to 200 nm.
[0468] Of the charge transport layers provided in adjacent to an
electrode, one having a function of improving charge injection
efficiency from the electrode and an effect of reducing the driving
voltage of the device is generally called particularly as a charge
injection layer (hole injection layer, electron injection layer) in
some cases.
[0469] To improve adhesion properties to an electrode and improve
charge injection from the electrode, the charge injection layer or
an insulating layer of 2 nm or less in thickness may be provided in
adjacent to the electrode. Alternatively, to improve adhesion
properties to the interface or to prevent contamination, a thin
buffer layer may be inserted into the interface between a charge
transport layer and a light-emitting layer.
[0470] The order, number and thickness of layers to be stacked can
be appropriately set in consideration of light emission efficiency
and the lifespan of a device.
[0471] In the present invention, as a polymer LED having a charge
injection layer (electron injection layer, hole injection layer)
provided therein, mention may be made of a polymer LED having a
charge injection layer in adjacent to a cathode and a polymer LED
having an charge injection layer in adjacent to an anode.
[0472] For example, the following structures e) to p) may be
specifically mentioned.
e) anode/charge injection layer/light-emitting layer/cathode f)
anode/light-emitting layer/charge injection layer/cathode g)
anode/charge injection layer/light-emitting layer/charge injection
layer/cathode h) anode/charge injection layer/hole transport
layer/light-emitting layer/cathode i) anode/hole transport
layer/light-emitting layer/charge injection layer/cathode j)
anode/charge injection layer/hole transport layer/light-emitting
layer/charge injection layer/cathode k) anode/charge injection
layer/light-emitting layer/electron transport layer/cathode l)
anode/light-emitting layer/electron transport layer/charge
injection layer/cathode m) anode/charge injection
layer/light-emitting layer/electron transport layer/charge
injection layer/cathode n) anode/charge injection layer/hole
transport layer/light-emitting layer/electron transport
layer/cathode o) anode/hole transport layer/light-emitting
layer/electron transport layer/charge injection layer/cathode p)
anode/charge injection layer/hole transport layer/light-emitting
layer/electron transport layer/charge injection layer/cathode.
[0473] Furthermore, in each of the structures, an interlayer may be
provided between the light-emitting layer and the anode adjacent to
the light-emitting layer. In this case, the interlayer may serve as
a hole injection layer and/or hole transport layer.
[0474] Specific examples of the charge injection layer include
[0475] a layer containing an electrically conductive polymer;
[0476] a layer formed between an anode and a hole transport layer
and containing ionization potential value between that of an anode
material and a hole transportable material contained in the hole
transport layer; and
[0477] a layer provided between a cathode and an electron transport
layer and having an electron affinity value between that of an
anode material and an electron transportable material contained in
the electron transport layer.
[0478] When the charge injection layer is a layer containing an
electrically conductive polymer, the electric conductivity of the
electrically conductive polymer is preferably 10.sup.-5 S/cm to
10.sup.3 (both inclusive), more preferably 10.sup.-5 S/cm to
10.sup.2 (both inclusive), and further preferably 10.sup.-5 S/cm to
10.sup.1 (both inclusive) to reduce a leakage current between
light-emitting pixels.
[0479] When the charge injection layer is a layer containing an
electrically conductive polymer, the electric conductivity of the
electrically conductive polymer is preferably 10.sup.-5 S/cm to
10.sup.3 S/cm (both inclusive), more preferably 10.sup.-5 S/cm to
10.sup.2 S/cm (both inclusive), and further preferably 10.sup.-5
S/cm to 10.sup.1 S/cm (both inclusive) to reduce a leakage current
between light-emitting pixels.
[0480] To set an electric conductivity of the electrically
conductive polymer at 10.sup.-5 S/cm to 10.sup.3 (both inclusive),
generally an appropriate amount of ions are doped in the
electrically conductive polymer.
[0481] The type of ions, if they are doped into a hole injection
layer, are anion and if they are doped into an electron injection
layer, are cations. Examples of the anions include polystyrene
sulfonic acid ion, alkylbenzene sulfonic acid ion and camphor
sulfonic acid ion. Examples of the cations include lithium ion,
sodium ion, potassium ion and tetrabutylammonium ion.
[0482] The film thickness of a charge injection layer is from 1 nm
to 100 nm, and preferably, 2 nm to 50 nm.
[0483] The material to be used in a charge injection layer may be
appropriately selected in connection with the material to be used
in a layer adjacent to an electrode. Examples thereof include
[0484] polyaniline or a derivative thereof;
[0485] polythiophene or a derivative thereof;
[0486] polypyrrole or a derivative thereof;
[0487] polyphenylenevinylene or a derivative thereof;
[0488] polythienylenevinylene or a derivative thereof;
[0489] polyquinoline or a derivative thereof;
[0490] polyquinoxaline or a derivative thereof;
[0491] an electrically conductive polymer such as a polymer
containing an aromatic amine structure in the main chain or a side
chain;
[0492] metal phthalocyanine (such as copper phthalocyanine);
and
[0493] carbon.
[0494] The insulating layer having a film thickness of 2 nm or less
has a function of facilitating charge injection. Examples of the
material of the insulating layer include a metal fluoride, metal
oxide and organic insulating material. Examples of a polymer LED
having an insulating layer of a film thickness of 2 nm or less
include
[0495] a polymer LED having an insulating layer having a film
thickness of 2 nm or less in adjacent to a cathode, and
[0496] a polymer LED having an insulating layer having a film
thickness of 2 nm or less in adjacent to an anode.
[0497] For example, the following structures q) to ab) may be
specifically mentioned.
q) anode/insulating layer having a film thickness of 2 nm or
less/light-emitting layer/cathode r) anode/light-emitting
layer/insulating layer having a film thickness of 2 nm or
less/cathode s) anode/insulating layer having a film thickness of 2
nm or less/light-emitting layer/insulating layer having a film
thickness of 2 nm or less/cathode t) anode/insulating layer having
a film thickness of 2 nm or less/hole transport
layer/light-emitting layer/cathode u) anode/hole transport
layer/light-emitting layer/insulating layer having a film thickness
of 2 nm or less/cathode v) anode/insulating layer having a film
thickness of 2 nm or less/hole transport layer/light-emitting
layer/insulating layer having a film thickness of 2 nm or
less/cathode w) anode/insulating layer having a film thickness of 2
nm or less/light-emitting layer/electron transport layer/cathode x)
anode/light-emitting layer/electron transport layer/insulating
layer having a film thickness of 2 nm or less/cathode y)
anode/insulating layer having a film thickness of 2 nm or
less/light-emitting layer/electron transport layer/insulating layer
having a film thickness of 2 nm or less/cathode z) anode/insulating
layer having a film thickness of 2 nm or less/hole transport
layer/light-emitting layer/electron transport layer/cathode aa)
anode/hole transport layer/light-emitting layer/electron transport
layer/insulating layer having a film thickness of 2 nm or
less/cathode ab) anode/insulating layer having a film thickness of
2 nm or less/hole transport layer/light-emitting layer/electron
transport layer/insulating layer having a film thickness of 2 nm or
less/cathode
[0498] Furthermore, in each of the structures, an interlayer may be
provided between the light-emitting layer and the anode in adjacent
to the light-emitting layer. In this case, the interlayer may serve
as a hole injection layer and/or hole transport layer.
[0499] When an interlayer is applied to the aforementioned
structures of a) to ab), the interlayer is preferably provided
between an anode and a light-emitting layer and formed of a
material which has an intermediate ionization potential between the
anode, hole injection layer, or a hole transport layer and a
polymer compound constituting the light-emitting layer.
[0500] Examples of the material for the interlayer include
[0501] a polyvinylcarbazole or a derivative thereof; and
[0502] a polymer having an aromatic amine in a side chain or the
main chain, such as a polyarylene derivative, arylamine derivative,
or triphenyl-diamine derivative.
[0503] The method of forming a film of an interlayer is not
limited; however, when a polymer material is used, a method of
forming a film from a solution may be mentioned.
[0504] As the solvent to be used for film formation from a
solution, a solvent capable of dissolving or homogeneously
dispersing a hole transportable material. Examples of the solvent
include
[0505] chlorine base solvents such as chloroform, methane chloride,
1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene and
o-dichlorobenzene;
[0506] ether base solvents such as tetrahydrofuran and dioxane;
aromatic hydrocarbon base solvents such as toluene and xylene;
[0507] aliphatic hydrocarbon base solvents such as cyclohexane;
methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane,
n-nonane and n-decane;
[0508] ketone base solvents such as acetone, methylethyl ketone and
cyclohexanone;
[0509] ester solvents such as ethyl acetate, butyl acetate, and
ethyl-cellosolve acetate;
[0510] polyhydric alcohols such as ethylene glycol, ethylene glycol
monobutyl ether, ethylene glycol monoethyl ether, ethylene glycol
monomethyl ether, dimethoxyethane, propylene glycol,
diethoxymethane, triethylene glycol monoethyl ether, glycerin, and
1,2-hexane diol, and derivatives of these;
[0511] alcohol base solvents such as methanol, ethanol, propanol,
isopropanol and cyclohexanol;
[0512] sulfoxide base solvents such as dimethylsulfoxide; and
[0513] amide base solvents such as N-methyl-2-pyrrolidone and
N,N-dimethylformamide.
[0514] These organic solvent may be used singly or in a combination
of theses.
[0515] Examples of the method of forming a film from a solution
include coating methods such as spin-coating method, casting
method, microgravure coating method, gravure-coating method,
bar-coating method, roll-coating method, wire-bar coating method,
dip-coating method, spray-coating method, screen printing method,
flexographic printing method, offset printing method, and inkjet
printing method.
[0516] The film thickness of an interlayer differs in optimal value
depending upon the material to be used and may be selected so as to
have appropriate driving voltage value and light emission
efficiency value. The film thickness is, for example, 1 nm to 1
.mu.m preferably 2 nm to 500 nm, and further preferably, 5 nm to
200 nm.
[0517] When the interlayer is provided in adjacent to a
light-emitting layer, in particular, when both layers are formed by
a coating method, the materials for the two layers are sometimes
mixed with each other and negatively affect the characteristics of
a device.
[0518] When the interlayer is provided by a coating method and
thereafter the light-emitting layer is formed by a coating method,
as a method of reducing contamination of the materials for the two
layers, mention may be made of a method in which the interlayer is
formed by a coating method and thereafter, the interlayer is heated
to render it insoluble to the organic solvent to be used for
forming the light-emitting layer, and then the light-emitting layer
is formed. The heating is generally performed at a temperature of
about 150.degree. C. to 300.degree. C. and generally for about 1
minute to 1 hour. In this case, components which fail to be
insoluble in the solvent can be removed by rinsing the interlayer
with the solvent to be used for forming the light-emitting layer
after heating and before forming the light-emitting layer. When
insolubilization treatment is sufficiently performed by heating,
rinse with the solvent is not required. To sufficiently perform
insolubilization treatment by heating, a polymer compound
containing at least one polymerizable group in a molecule is
preferably used in the interlayer. In addition, the number of
polymerizable groups is preferably 5% relative to the number of
repeat units in a molecule.
[0519] As a substrate on which a polymer LED according to the
present invention is formed, any substrate may be used as long as
it cannot be influenced when an electrode is formed and then an
organic material layer is formed. Examples of the substrate include
substrates formed of glass, plastic, polymer film and silicon. When
an opaque substrate is used, the opposite electrode is preferably
transparent or semitransparent.
[0520] Generally, in a polymer LED according to the present
invention, at least one of the anode or cathode is transparent or
semitransparent. The anode is preferably transparent or
semitransparent.
[0521] As the material for the anode, use may be made of, for
example, a conductive metal oxide film and semitransparent metal
thin film. Specific examples thereof include a film (NESA) formed
of electrically conductive glass made of, for example, indium
oxide, zinc oxide, tin oxide; and composites these such as indium
tin oxide (ITO), indium/zinc/oxide, gold, platinum, silver and
copper; and ITO, indium/zinc/oxide and tin oxide are preferable.
Examples of the forming method include a vacuum deposition method,
sputtering method, ion plating method and plating method.
Furthermore, as the anode, use may be made of an organic
electrically conductive film such as polyaniline or a derivative
thereof or polythiophene or a derivative thereof.
[0522] The film thickness of an anode may be appropriately set in
consideration of light permeability and electric conductivity, and
is for example, 10 nm to 10 .mu.m, preferably, 20 nm to 1 .mu.m,
and further preferably, 50 nm to 500 nm.
[0523] To facilitate injection of charge, a layer having an average
thickness of 2 nm and formed of a phthalocyanine derivative,
electrically conductive polymer or carbon or formed of a metal
oxide, metal fluoride or an organic insulating material, may be
provided on the anode.
[0524] As a material for the cathode to be used in a polymer LED
according to the present invention, one having a small work
function is preferable. Examples of the material to be used
include
[0525] metals such as lithium, sodium, potassium, rubidium, cesium,
beryllium, magnesium, calcium, strontium, barium, aluminum,
scandium, vanadium, zinc, yttrium, indium, cerium, samarium,
europium, terbium, and ytterbium;
[0526] alloys formed of at least two of them;
[0527] alloys formed of at least one of them and one selected from
the group consisting of gold, silver, platinum, copper, manganese,
titanium, cobalt, nickel, tungsten and tin;
[0528] graphite; and a graphite intercalation compound.
[0529] Examples of the alloy include
[0530] Magnesium-silver alloy, magnesium-indium alloy,
magnesium-aluminum alloy, indium-silver alloy, lithium-aluminum
alloy, lithium-magnesium alloy, lithium-indium alloy and
calcium-aluminum alloy. The cathode may have a stacked structure
consisting of two or more layers.
[0531] The film thickness of a cathode may be appropriately set in
consideration of electric conductivity and durability, and is for
example, 10 nm to 10 .mu.m, preferably 20 nm to 1 .mu.m and further
preferable 50 nm to 500 nm.
[0532] Examples of the method of forming a cathode include a vacuum
deposition method, sputtering method, laminate method in which a
metal thin film is formed by thermocompression bonding.
Furthermore, a layer formed of an electrically conductive polymer
or a layer formed of e.g., a metal oxide, metal fluoride, or
organic insulating material and having an average film thickness of
2 nm or less may be provided between the cathode and an organic
layer. Alternatively, after the cathode is formed, a protecting
layer for protecting the polymer LED may be applied. To use the
polymer LED stably for a long time, the device may be externally
protected preferably with a protecting layer and/or a protecting
cover.
[0533] As the protecting layer, use may be made of e.g., a polymer
compound, metal oxide, metal fluoride and metal borate.
Furthermore, as the protecting cover, use may be made of e.g.,
glass plate and plastic plate on the surface of which treatment of
lowing water permeability is applied. A method of adhering the
cover tight with the substrate of a device with a thermoplastic
resin or a photosetting resin, thereby sealing them, is preferably
used. It is easy to prevent the device from being damaged by
keeping a space by use of a spacer. If an inert gas such as
nitrogen or argon is introduced into the space, it is possible to
prevent oxidation of the cathode. Furthermore, if a desiccating
agent such as barium oxide is placed in the space, it is possible
to suppress a moisture content adsorbed in the manufacturing step
from damaging the device. At least one of the methods is preferably
employed.
[0534] A polymer LED according to the present invention may be used
as a planar light source or a backlight of a segment type display
device, a dot matrix display device and a liquid crystal display
device.
[0535] To obtain planar light emission by use of a polymer LED
according to the present invention, a planar anode and a planar
cathode are placed so as to overlap with each other. To obtain
patterned light emission, there are
[0536] a method in which a mask having a patterned window is
provided on the surface of the planar light-emitting device;
[0537] a method in which an organic material layer used in non
light-emitting portion is formed extremely thick substantially not
to emit light from the portion; and
[0538] a method in which any one of or both of the anode and
cathode are formed so as to have a pattern.
[0539] A pattern is formed in accordance with any one of the
methods, and several electrodes are arranged so as to independently
turn ON/Off. In this way, it is possible to obtain a segment type
display device capable of displaying numerical values, characters,
and simple symbols. Furthermore, to obtain a dot-matrix device,
both an anode and a cathode may be formed in stripe form and
arranged so as to cross perpendicularly with each other. Sector
color display and multicolor display can be attained by a method of
separately applying a plurality of types of polymer phosphors
different in emission color, or by a method of using a color filter
or a fluorescent conversion filter. A dot matrix device can be
driven passively and may be driven actively in combination with,
for example, TFT. These display devices can be used as display
devices of a computer, television, portable handheld unit, mobile
phone, car navigation and a view finder of a video camera, etc.
[0540] Furthermore, the planar light-emitting device is a thin-film
spontaneous light-emitting device and suitably used as a planar
light source for a backlight of a liquid crystal display device or
a planar illumination light source. Furthermore, if a flexible
substrate is used, the planar light emitting device can be used
also as a curved surface light source or display device.
EXAMPLES
[0541] Now, the present invention will be more specifically
explained with reference to Examples below, which will not be
construed as limiting the invention.
[0542] The number average molecular weight in terms of polystyrene
was obtained by SEC.
[0543] Column: TOSOH, TSKgel Super HM-H (2 columns+TSKgel Super H
2000 (4.6 mm 1.d..times.15 cm), detector: RI (SHIMADZU RID-10A),
Tetrahydrofuran (THF) was used as a mobile phase.
Synthesis Example 1
Synthesis of Compound M-1
##STR00119##
[0545] In a 300 ml four-neck flask, N-phenyl-1,4-phenylenediamine
(5.53 g, 30 mmol), 4-bromo-n-butylbenzene (25.57 g, 120 mmol),
Pd.sub.2(dba).sub.3 (820 mg, 0.9 mmol), t-BuONa (8.65 g, 90 mmol)
and toluene (120 ml) were mixed under an argon atmosphere. To the
reaction solution, (t-Bu).sub.3P (360 mg, 1.8 mmol) was added and
heated to 100.degree. C. for 3 hours. After cooling, 200 ml of
toluene was added. The reaction solution was washed with an aqueous
NaCl solution (100 ml.times.3) and subsequently with water (200
ml). After the organic layer was dried over sodium sulfate, it was
concentrated. The obtained liquid was purified by silica gel column
chromatography (toluene:hexane=1:3) and thereafter further purified
by silica gel column chromatography (hexane.fwdarw.toluene:
hexane=1:3) to obtain 10.2 g of compound M-1.
[0546] .sup.1H-NMR; .delta. 0.97 (9H, t), 1.37 (6H, m), 1.58 (6H,
m), 2.55 (6H, t), 6.85-7.07 (18H, m), 7.17 (2H, t).
Synthesis Example 2
##STR00120##
[0548] In a 100 ml four-neck flask, compound M-1(1.45 g, 2.5 mmol),
NBS (0.49 g, 0.27 mmol) and DMF (20 ml) were mixed under an argon
atmosphere. The reaction solution was stirred at 0.degree. C. for 4
hours. After completion of the reaction, 100 ml of hexane was
added. The reaction mixture was washed with an aqueous KCl solution
(100 ml.times.2) and subsequently with water (100 ml.times.2).
After the organic layer was dried over sodium sulfate, it was
concentrated. The obtained liquid was purified by silica gel column
chromatography (toluene: hexane=1:6), twice to obtain 960 mg of
compound M-2. LC-MS (APCI method); m/z 660.2 ([M+H].sup.+)
Synthesis Example 3
Synthesis of Compound M-3
##STR00121##
[0550] In a 300 ml three-neck flask, 8-bromooctene (1.91 g, 10
mmol) and THF (10 ml) were mixed under an argon atmosphere. To
this, 9-BBN/0.5M-THF solution (20 ml, 10 mmol) was added dropwise
at room temperature for 20 minutes and stirred at room temperature
for 12 hours.
[0551] To the reaction solution, compound M-2 (2.64 g, 4.0 mmol),
PdCl.sub.2 (dppf)(160 mg, 0.20 mmol), THF (10 ml) and an aqueous 3M
NaOH solution (7 ml) were added. The resultant reaction solution
was refluxed for 4.5 hours. After completion of the reaction, the
reaction solution was cooled. To the reaction solution, hexane (20
ml) was added. While cooling the reaction solution with water, a
hydrogen peroxide solution (2 ml) was added dropwise for 10 minutes
and stirred at room temperature for 3 hours. The obtained organic
layer was washed with water (200 ml.times.3), dried over sodium
sulfate, concentrated and purified by silica gel column
chromatography (toluene:hexane=1:10.fwdarw.toluene:hexane=1:3)
twice to obtain 1.81 g of compound M-3.
[0552] LC-MS (APCI method); m/z 772.3 ([M+H].sup.+)
Synthesis Example 4
Synthesis of Compound M-4
##STR00122##
[0554] In a 100 mL eggplant flask, 2,7-dibromofluorenon (0.379 mg,
1.1 mmol), compound M-1 (1.37 g, 2.3 mmol), methane sulfonic acid
(a single drop, catalyst amount), and toluene (6 ml) were mixed
under an argon atmosphere, and refluxed for 15 hours. After
cooling, 30 ml of toluene was added. The reaction solution was
washed with an aqueous NaHCO.sub.3 solution (100 ml.times.3) and
subsequently with water (50 ml.times.2). The organic layer was
dried over sodium sulfate and concentrated. The obtained liquid was
purified by silica gel column chromatography (toluene:hexane=3:1)
and thereafter further purified by silica gel column chromatography
(toluene:hexane=6:1) to obtain 820 mg of compound M-4.
[0555] LC-MS (APCI method); m/z 1482.5 ([M+H].sup.+)
Synthesis Example 5
Synthesis of Compound M-5
##STR00123##
[0557] In a 100 mL eggplant flask, 2,7-dihydro-9,9-dihydrofluorene
(0.26 g, 0.8 mmol), compound M-3 (1.85 g, 2.4 mmol),
tetrabutylammonium bromide (50 mg, 0.8 mmol), an aqueous 50% sodium
hydroxide solution (5 ml) and toluene (20 ml) were mixed under an
argon atmosphere and refluxed for 13 hours. After cooling, 30 ml of
toluene was added. The reaction solution was washed with water (50
ml.times.2). The organic layer was dried over sodium sulfate and
concentrated. The obtained liquid was purified by silica gel column
chromatography (toluene:hexane=1:5) and thereafter further purified
by silica gel column chromatography (toluene:hexane=1:40) to obtain
820 mg of compound M-5.
[0558] LC-MS (APCI method); m/z 1705 ([M+H].sup.+)
Synthesis Example 6
Synthesis of Compound M-6
##STR00124##
[0560] In a 300 ml three-neck flask, 8-bromooctene (12.61 g, 66
mmol) and THF (40 ml) were mixed under an argon atmosphere. To
this, 9-BBN/0.5M-THF solution (132 ml, 66 mmol) was added dropwise
at room temperature for 50 minutes and stirred at room temperature
for 16 hours.
[0561] To the reaction solution, a compound, 9-bromoanthracene
(7.71 g, 30 mmol), PdCl.sub.2(dppf) (1.22 g, 1.5 mmol), THF (60 ml)
and an aqueous 3M-NaOH solution (40 ml) were added and refluxed for
6.5 hours. After completion of the reaction, the reaction solution
was cooled and hexane (70 ml) was added to the reaction solution.
While cooling the reaction solution with water, a hydrogen peroxide
solution (10 ml) was added dropwise for 30 minutes and stirred at
room temperature for 4 hours. The obtained organic layer was washed
with water (200 ml.times.3), dried over sodium sulfate,
concentrated, and purified by silica gel column chromatography
twice (hexane-*toluene=1:2) to obtain 3.4 g of compound M-6.
[0562] LC-MS (APCI method); m/z 370.1 ([M+H].sup.+)
[0563] .sup.1H-NMR; .delta. 1.42 (8H, t), 1.86 (4H, m), 3.41 (2H,
t), 3.60 (2H, t), 7.46 (4H, m), 7.99 (2H, d), 8.26 (2H, d), 8.33
(1H, s).
Synthesis Example 7
Synthesis of Compound M-7
##STR00125##
[0565] In a 100 mL eggplant flask, 2,7-dihydro-9,9-dihydrofluorene
(0.62 g, 1.9 mmol), compound M-6 (1.54 g, 4.1 mmol)
tetrabutylammonium bromide (140 mg, 1.9 mmol), an aqueous 50%
sodium hydroxide solution (10 ml) and toluene (20 ml) were mixed
under an argon atmosphere and refluxed for 5 hours. After cooling,
40 ml of toluene was added. The reaction solution was washed with
water (50 ml.times.2). The organic layer was dried over sodium
sulfate and concentrated. The obtained liquid was purified by
silica gel column chromatography (toluene: hexane=1:1) and
thereafter further purified by silica gel column chromatography
(hexane) to obtain 830 mg of compound M-7.
[0566] LC-MS (APCI method); m/z 901.1 ([M+H].sup.+).
[0567] .sup.1H-NMR; .delta. 0.72 (2H, m), 1.18-1.35 (6H, m), 1.57
(2H, m), 1.83 (2H, m), 2.00 (2H, t), 3.66 (2H, t), 7.55 (10H, m),
8.10 (2H, d), 8.34 (2H, d), 8.41 (1H, s).
Synthesis Example 8
Synthesis of Compound M-8
##STR00126##
[0569] In a 200 mL eggplant flask, 2,7-dihydro-9,9-dihydrofluorene
(2.94 g, 8.7 mmol), phenyl-di-p-toluoylamine (4.99 g, 18.3 mmol)
methane sulfonic acid (0.84 g, catalyst amount) and toluene (44 ml)
were mixed under an argon atmosphere and refluxed for 15 hours.
After cooling, 150 ml of toluene was added. The reaction solution
was washed with an aqueous 2M NaHCO.sub.3 solution (100 ml.times.3)
and subsequently with water (100 ml.times.2). The organic layer was
dried over sodium sulfate and concentrated. The obtained oil was
purified by silica gel column chromatography (toluene: hexane=3:1)
to obtain 1.33 g of compound M-8.
[0570] LC-MS (APCI method); m/z 865 ([M+H].sup.+)
Example 1
Synthesis of Polymer Compound P-1
##STR00127##
[0572] Compound M-4 (0.500 g) and 2,2'-bipyridyl (0.126 g) were
dissolved, under an inert atmosphere, in dehydrated tetrahydrofuran
(24 mL) previously bubbled with argon. Subsequently,
bis(1,5-cyclooctadien)nickel (O){Ni(COD).sub.2} (0.223 g) was added
to the reaction solution and stirred. After the temperature of the
solution was raised to 60.degree. C., the reaction was performed
for 3 hours.
[0573] The reaction solution was cooled to room temperature and
added dropwise to a solution mixture of 25% ammonia water (1
mL)/methanol (24 mL)/ion exchanged water (24 mL) and stirred for
one hour. Thereafter, the precipitated substance was filtrated,
dried under reduced pressure and subsequently dissolved in toluene
(10 mL). To this, Radiolite (0.04 g) was added and stirred for 30
minutes. After insoluble matter was filtrated, the filtrate was
purified through an alumina column. Subsequently, 4% ammonia water
(20 mL) was added and stirred for 2 hours, and then the water layer
was removed. Further, to the organic layer, about 20 mL of ion
exchanged water was added and stirred for one hour, and then the
water layer was removed. Thereafter, the organic layer was added to
60 ml of methanol and stirred for 0.5 hours. The precipitated
substance was filtrated and dried under reduced pressure to obtain
0.28 g of polymer compound P-1.
[0574] Note that the number average molecular weight and weight
average molecular weight thereof in terms of polystyrene were
Mn=9.8.times.10.sup.4 and Mw=2.3.times.10.sup.5, respectively.
Example 2
Synthesis of Polymer Compound P-2
##STR00128##
[0576] Compound M-5 (0.300 g) and 2,2'-bipyridyl (0.066 g) were
dissolved, under an inert atmosphere, in dehydrated tetrahydrofuran
(13 mL) previously bubbled with argon. Subsequently,
bis(1,5-cyclooctadien)nickel (O){Ni(COD).sub.2} (0.116 g) was added
to the reaction solution and stirred. After the temperature of the
solution was raised to 60.degree. C., the reaction was performed
for 3 hours.
[0577] The reaction solution was cooled to room temperature and
added dropwise to a solution mixture of 25% ammonia water (1
mL)/methanol (13 mL)/ion exchanged water (13 mL) and stirred for
one hour. Thereafter, the precipitated substance was filtrated,
dried under reduced pressure and subsequently dissolved in toluene
(5 mL). To this, Radiolite (0.02 g) was added and stirred fro 30
minutes. After insoluble matter was filtrated, the filtrate was
purified through an alumina column. Subsequently, 4% ammonia water
(10 mL) was added and stirred for 2 hours, and then the water layer
was removed. Further, to the organic layer, about 10 mL of ion
exchanged water was added and stirred for one hour, and then the
water layer was removed. Thereafter, the organic layer was
concentrated to 4 g under reduced pressure, added to 15 ml of
methanol and stirred for 0.5 hours. The precipitated substance was
filtrated and dried under reduced pressure to obtain 0.12 g of
polymer compound P-2.
[0578] Note that the number average molecular weight and weight
average molecular weight thereof in terms of polystyrene were
Mn=7.4.times.10.sup.4 and Mw=1.5.times.10.sup.5, respectively.
Synthesis Example 9
Synthesis of Compound P-3
##STR00129##
[0580] After 2,7-dibromo-9,9-di-n-octylfluorene (26.3 g, 48.0
mmol), 2,7-dibromo-9,9-bis(3-methylbutyl)fluorene (5.6 g, 12.0
mmol), and 2,2'-bipyridyl (22 g, 14.1 mmol) were dissolved in
dehydrated tetrahydrofuran (1600 mL), the atmosphere of the
reaction system was replaced with nitrogen by bubbling with
nitrogen. To this solution, bis(1,5-cyclooctadien)nickel
(O){Ni(COD).sub.2} (40.66 g, 147.8 mmol) was added under the
nitrogen atmosphere. The temperature of the solution was raised to
60.degree. C. and the reaction was performed for 8 hours while
stirring. After completion of the reaction, the reaction solution
was cooled to room temperature (about 25.degree. C.) and added
dropwise to a solution mixture of 25% ammonia water (1200
mL)/methanol (1200 mL)/ion exchanged water (1200 mL) and stirred
for 0.5 hours. Thereafter, the precipitated substance was
filtrated, dried under reduced pressure for 2 hours, and
subsequently dissolved in toluene (1110 mL) and filtrated. To the
filtrate, toluene was added to obtain a solution of about 2800 mL.
After that, the organic layer was washed with 2000 ml of an aqueous
1N hydrochloric acid solution for one hour, 2200 mL of a 4% ammonia
water for one hour, 1000 mL of ion exchanged water for 10 minutes,
and further, with 1000 mL of ion exchanged water for 10 minutes.
The organic layer was concentrated at 50.degree. C. to 592 g under
reduced pressure, added dropwise to 3330 mL of methanol, and
stirred for 0.5 hours. The precipitated substance was filtrated,
washed with 500 mL of methanol twice, and dried at 50.degree. C.
for 5 hours under reduced pressure. The yield of the obtained
polymer compound P-3 was 12.6 g.
[0581] Note that the number average molecular weight and weight
average molecular weight of polymer compound P-3 in terms of
polystyrene were Mn=8.7.times.10.sup.4 and Mw=1.8.times.10.sup.5,
respectively.
Synthesis Example 10
Synthesis of Compound P-4
##STR00130##
[0583] After 2,7-dibromo-9,9-dioctylfluorene (0.50 g, 0.90 mmol),
N--N'-bis(4-n-butylphenyl)-N,N'-bis(4-bromophenyl)-1,4-phenylenediamine
(0.27 g, 0.37 mmol) and 2,2'-bipyridyl (0.47 g, 3.1 mmol) were
dissolved in dehydrated tetrahydrofuran (30 mL), the atmosphere of
the reaction system was replaced with nitrogen by bubbling with
nitrogen. To this solution, bis(1,5-cyclooctadien)nickel
(O){Ni(COD).sub.2}(0.90 g, 3.3 mmol) was added under the nitrogen
atmosphere. The temperature of the solution was raised to
60.degree. C. and the reaction was performed for 3 hours. After
completion of the reaction, the reaction solution was cooled and
added dropwise to a solution mixture of 25% ammonia water (10
mL)/methanol (120 mL)/ion exchanged water (50 mL) and stirred for
about one hour. Subsequently, the precipitate generated was
collected by filtration. The precipitate was washed with ethanol
and dried for 2 hours under reduced pressure. Subsequently, the
precipitate was dissolved in toluene (30 mL). To this, 1N
hydrochloric acid (30 mL) was added and stirred for one hour. The
water layer was removed and 4% ammonia water (30 mL) was added to
the organic layer and stirred for one hour and then the water layer
was removed. The organic layer was added dropwise to 200 mL of
methanol and stirred for one hour. The precipitated substance was
filtrated and dried under reduced for 2 hours pressure and then
dissolved in 30 mL of toluene. Thereafter, the solution was
purified through an alumina column (the amount of alumina: 20 g).
The collected toluene solution was added dropwise to 250 mL of
methanol and stirred for one hour. The precipitated substance was
filtrated and dried for 2 hours under reduced pressure. The yield
of the obtained polymer compound P-4 was 0.32 g.
[0584] Note that the number average molecular weight and weight
average molecular weight of polymer compound P-4 in terms of
polystyrene were 2.3.times.10.sup.4 and 8.5.times.10.sup.4,
respectively.
Example 3
Synthesis of Polymer Compound P-5
##STR00131##
[0586] Compound M-4 (0.516 g), 2,7-dibromo-9,9-dioctylfluorene
(0.254 g), 2,7-bis(1,3,2-dioxaboran-2-yl)-9,9-dioctylfluorene
(0.424 g), palladium acetate (0.5 mg), tri(2-methylphenyl)phosphine
(2.0 mg), Aliquat 336 (0.2 g, manufactured by Aldrich), toluene (10
ml) and an aqueous 2M Na.sub.2CO.sub.3 solution (2 ml) were mixed
under an inert atmosphere and refluxed for 3 hours. After
completion of the reaction, a solution mixture of phenylboric acid
(20 mg) and THF (2 ml) was added and further refluxed for 4 hours.
Subsequently, an aqueous solution of sodium diethyldithiacarbamate
was added to this and stirred at 85.degree. C. for 4 hours. After
cooling, the reaction solution was washed with water (30 ml) three
times, 3% an aqueous acetic acid solution (30 ml) four times and
water (30 ml) three times, and purified through an alumina column
and a silica gel column. The obtained toluene solution was added
dropwise to methanol (250 ml) and stirred for one hour. Thereafter,
the obtained solid substance was filtrated and dried. The yield of
the obtained polymer compound P-5 was 719 mg.
[0587] Note that the number average molecular weight and weight
average molecular weight of polymer compound P-5 in terms of
polystyrene were 4.5.times.10.sup.4 and 1.1.times.10.sup.5,
respectively.
Example 4
Synthesis of Polymer Compound P-6
##STR00132##
[0589] Compound M-5 (0.475 g), 2,7-dibromo-9,9-dioctylfluorene
(0.204 g), 2,7-bis(1,3,2-dioxaboran-2-yl)-9,9-dioctylfluorene
(0.339 g), palladium acetate (0.4 mg), tri(2-methylphenyl)phosphine
(1.8 mg), Aliquat 336 (0.2 g, manufactured by Aldrich), toluene (9
ml) and an aqueous 2M Na.sub.2CO.sub.3 solution (2 ml) were mixed
under an inert atmosphere and refluxed for 3 hours. After
completion of the reaction, a solution mixture of phenylboric acid
(20 mg) and THF (2 ml) was added and further refluxed for 4 hours.
Subsequently, an aqueous solution of sodium diethyldithiacarbamate
was added to this and stirred at 85.degree. C. for 4 hours. After
cooling, the reaction solution was washed with water (30 ml) three
times, 3% an aqueous acetic acid solution (30 ml) four times and
water (30 ml) three times, and purified through an alumina column
and a silica gel column. The obtained toluene solution was added
dropwise to methanol (250 ml) and stirred for one hour. Thereafter,
the obtained solid substance was filtrated and dried. The yield of
the obtained polymer compound P-6 was 451 mg.
[0590] Note that the number average molecular weight and weight
average molecular weight of polymer compound P-6 in terms of
polystyrene were 6.6.times.10.sup.4 and 1.7.times.10.sup.5,
respectively.
Example 5
Synthesis of Polymer Compound P-7
##STR00133##
[0592] Compound M-4 (0.534 g), 2,7-dibromo-3,6-octyloxydibenzofuran
(0.490 g), 2,7-bis(1,3,2-dioxaboran-2-yl)-9,9-dioctylfluorene
(0.640 g), bis(triphenylphosphine)palladium dichloride (0.9 mg),
Aliquat 336 (0.2 g, manufactured by Aldrich), toluene (9 ml) and an
aqueous 2M Na.sub.2CO.sub.3 solution (3 ml) were mixed under an
inert atmosphere and refluxed for 3 hours. After completion of the
reaction, a solution mixture of phenylboric acid (20 mg) and THF (2
ml) was added and further refluxed for 4 hours. Subsequently, an
aqueous solution of sodium diethyldithiacarbamate was added to this
and stirred at 85.degree. C. for 4 hours. After cooling, the
reaction solution was washed with water (30 ml) three times, 3%; an
aqueous acetic acid solution (30 ml) four times and water (30 ml)
three times, and purified through an alumina column and a silica
gel column. The obtained toluene solution was added dropwise to
methanol (250 ml) and stirred for one hour. Thereafter, the
obtained solid substance was filtrated and dried. The yield of the
obtained polymer compound P-7 was 772 mg.
[0593] Note that the number average molecular weight and weight
average molecular weight of polymer compound P-7 in terms of
polystyrene were 8.0.times.10.sup.4 and 3.1.times.10.sup.5,
respectively.
[0594] Note that 2,7-dibromo-3,6-dioctyloxydibenzofuran was
synthesized in accordance with the method described in
JP-A-2004-059899.
Example 6
Synthesis of Polymer Compound P-8
##STR00134##
[0596] Compound M-5 (0.356 g),
2,7-dibromo-3,6-octyloxydibenzothiophene (0.575 g),
2,7-bis(1,3,2-dioxaboran-2-yl)-9,9-dioctylfluorene (0.640 g),
bis(triphenylphosphine)palladium dichloride (0.9 mg), Aliquat 336
(0.2 g, manufactured by Aldrich), toluene (9 ml) and an aqueous 2M
Na.sub.2CO.sub.3 solution (3 ml) were mixed under an inert
atmosphere and refluxed for 3 hours. After completion of the
reaction, a solution mixture of phenylboric acid (20 mg) and THF (2
ml) was added and further refluxed for 4 hours. Subsequently, an
aqueous solution of sodium diethyldithiacarbamate was added to this
and stirred at 85.degree. C. for 4 hours. After cooling, the
reaction solution was washed with water (30 ml) three times, 3% an
aqueous acetic acid solution (30 ml) four times and water (30 ml)
three times, and purified through an alumina column and a silica
gel column. The obtained toluene solution was added dropwise to
methanol (250 ml) and stirred for one hour. Thereafter, the
obtained solid substance was filtrated and dried. The yield of the
obtained polymer compound P-8 was 98 mg.
[0597] Note that the number average molecular weight and weight
average molecular weight of polymer compound P-8 in terms of
polystyrene were 2.7.times.10.sup.4 and 8.0.times.10.sup.4,
respectively.
[0598] Note that 2,7-dibromo-3,6-dioctyloxydibenzothiophene was
synthesized in accordance with the method described in
JP-A-2004-002703.
Example 7
Synthesis of Polymer Compound P-9
##STR00135##
[0600] Compound M-7 (0.325 g), 2,7-dibromo-9,9-dioctylfluorene
(0.461 g), 2,7-bis(1,3,2-dioxaboran-2-yl)-9,9-dioctylfluorene
(0.640 g), bis(triphenylphosphine)palladium dichloride (0.9 mg),
Aliquat 336 (0.2 g, manufactured by Aldrich), toluene (9 ml) and an
aqueous 2M Na.sub.2CO.sub.3 solution (3 ml) were mixed under an
inert atmosphere and refluxed for 3 hours. After completion of the
reaction, a solution mixture of phenylboric acid (20 mg) and THF (2
ml) was added and further refluxed for 4 hours. Subsequently, an
aqueous solution of sodium diethyldithiacarbamate was added to this
and stirred at 85.degree. C. for 4 hours. After cooling, the
reaction solution was washed with water (30 ml) three times, 3% an
aqueous acetic acid solution (30 ml) four times and water (30 ml)
three times, and purified through an alumina column and a silica
gel column. The obtained toluene solution was added dropwise to
methanol (250 ml) and stirred for one hour. Thereafter, the
obtained solid substance was filtrated and dried. The yield of the
obtained polymer compound P-9 was 510 mg.
[0601] Note that the number average molecular weight and weight
average molecular weight of polymer compound P-9 in terms of
polystyrene were 8.3.times.10.sup.4 and 1.6.times.10.sup.5,
respectively.
Synthesis Example 11
Synthesis of Compound P-10
##STR00136##
[0603] Compound M-8 (0.312 g), 2,7-dibromo-9,9-dioctylfluorene
(0.461 g), 2,7-bis(1,3,2-dioxaboran-2-yl)-9,9-dioctylfluorene
(0.640 g), bis(triphenylphosphine)palladium dichloride (0.9 mg),
Aliquat 336 (0.2 g, manufactured by Aldrich), toluene (9 ml) and an
aqueous 2M Na.sub.2CO.sub.3 solution (3 ml) were mixed under an
inert atmosphere and refluxed for 3 hours. After completion of the
reaction, a solution mixture of phenylboric acid (20 mg) and THF (2
ml) was added and further refluxed for 4 hours. Subsequently, an
aqueous solution of sodium diethyldithiacarbamate was added to this
and stirred at 85.degree. C. for 4 hours. After cooling, the
reaction solution was washed with water (30 ml) three times, 3% an
aqueous acetic acid solution (30 ml) four times and water (30 ml)
three times, and purified through an alumina column and a silica
gel column. The obtained toluene solution was added dropwise to
methanol (250 ml) and stirred for one hour. Thereafter, the
obtained solid substance was filtrated and dried. The yield of the
obtained polymer compound P-10 was 510 mg.
[0604] Note that the number average molecular weight and weight
average molecular weight of polymer compound P-10 in terms of
polystyrene were 9.4.times.10.sup.4 and 2.5.times.10.sup.5,
respectively.
[0605] HOMO and LUMO energy values were determined by cyclic
voltammetry (ALS 600, manufactured by P.A.S) and measured in an
acetonitrile solvent containing 0.1 wt % tetrabutyl
ammonium-tetrafluoroborate. A polymer compound was dissolved in
chloroform so as to obtain a concentration of about 0.2 wt %. To
the working pole, 1 mL of the chloroform solution of the polymer
compound was then applied and the solvent was vaporized to form a
thin film of the polymer compound. Measurement was performed using
silver/silver ion electrode as a reference electrode and a grassy
carbon electrode as a working electrode, and a platinum electrode
as the opposite electrode in a glove box purged with nitroaen. The
sweep rates of potentials all were measured at 50 mV/s.
Example 8
Measurement of Oxidation Potential
[0606] Polymer compound P-1 was dissolved in chloroform to prepare
0.2 wt % solution. The solution (0.05 mL) was applied onto a
platinum electrode and chloroform was vaporized to prepare a thin
film of polymer compound P-1. The measurement was performed in the
same manner as above. Based on the obtained oxidation potential,
HOMO energy was calculated.
Example 9
Measurement of Oxidation Potential
[0607] The oxidation potential of polymer compound P-2 was measured
by the method mentioned above. Based on the obtained oxidation
potential, HOMO energy was calculated.
Comparative Example 1
Measurement of Oxidation Potential
[0608] The oxidation potential of polymer compound P-3 was measured
by the method mentioned above. Based on the obtained oxidation
potential, HOMO energy was calculated.
TABLE-US-00001 TABLE 1 Comparative Example 8 Example 9 Example 1
Polymer compound P-1 P-2 P-3 Oxidation potential (mV) 307 272 968
Absolute value of HOMO energy 5.3 5.2 5.9 (eV)
Example 10
Measurement of Oxidation Potential
[0609] The oxidation potential of polymer compound P-5 was measured
by the method mentioned above. Based on the obtained oxidation
potential, HOMO energy was calculated.
Example 11
Measurement of Oxidation Potential
[0610] The oxidation potential of polymer compound P-6 was measured
by the method mentioned above. Based on the obtained oxidation
potential, HOMO energy was calculated.
<Measurement of Oxidation Potential>
[0611] The oxidation potential of polymer compound P-10 was
determined in the same manner as above. Based on the obtained
oxidation potential, HOMO energy was calculated.
TABLE-US-00002 TABLE 2 Comparative Example 10 Example 11 Example 2
Polymer compound P-5 P-6 P-10 Oxidation potential (mV) 267 307 643
Absolute value of HOMO 5.22 5.26 5.59 energy (eV)
Example 12
Preparation of Solution
[0612] Polymer compound P-1 obtained above was dissolved in toluene
to prepare a toluene solution of a polymer concentration of 1.2 wt
%.
Preparation of EL Device
[0613] On a glass substrate on which an ITO film of 150 nm thick is
formed by a sputtering method, a thin film of 70 nm thick was
formed by spin-coating using a solution obtained by filtrating a
suspension solution of poly(3,4)ethylenedioxythiophene/polystyrene
sulfonic acid (BaytronP AI4083, manufactured by Bayer) through a
0.2 .mu.m membrane filter, and dried on a hot plate at 200.degree.
C. for 10 minutes. Subsequently, using the toluene solution
obtained above, a film was formed by spin coating at a rotation
rate of 1000 rpm. The film thickness of the formed film was about
71 nm. Furthermore, the film was dried under reduced pressure at
80.degree. C. for one hour and then lithium fluoride was deposited
to a thickness of about 4 nm. Calcium was deposited to a thickness
of about 5 nm as a cathode, and then, aluminum was deposited to a
thickness of about 72 nm. In this manner, an EL device was
prepared. Note that deposition of a metal was initiated after a
degree of vacuum reached 1.times.10.sup.-4 Pa or less.
Performance of EL Device
[0614] When voltage was applied to the obtained device, EL light
emission having a peak at 500 nm was obtained from the device. The
intensity of EL light emission was almost in proportional to a
current density. The maximum light emission efficiency of the
device was 0.58 cd/A.
[0615] Furthermore, the voltage when the brightness exhibited 1.0
cd/m.sup.2 was 3.44 V.
Example 13
Preparation of Solution
[0616] Polymer compound P-5 obtained above was dissolved in xylene
to prepare a xylene solution of a polymer concentration of 1.5 wt
%.
Preparation of EL Device
[0617] An EL device was prepared in substantially the same manner
as in Example 12 except that the xylene solution obtained above was
used. The rotation number during spin coating was 1500 rpm and the
thickness of the obtained polymer film was 74 nm.
Performance of EL Device
[0618] When voltage was applied to the obtained device, EL light
emission having a peak at 480 nm was obtained from the device. The
intensity of EL light emission was almost in proportional to a
current density. The maximum light emission efficiency of the
device was 0.59 cd/A.
[0619] Furthermore, the voltage when the brightness exhibited 1.0
cd/m.sup.2 was 3.48 V.
Comparative Example 3
Preparation of Solution
[0620] Polymer compound P-10 obtained above was dissolved in xylene
to prepare a xylene solution of a polymer concentration of 1.5 wt
%.
Preparation of EL Device
[0621] An EL device was prepared in substantially the same manner
as in Example 12 except that the xylene solution obtained above was
used. The rotation number during spin coating at this time was 1500
rpm and the thickness of the obtained film was 74 nm.
Performance of EL Device
[0622] When voltage was applied to the obtained device, EL light
emission having a peak at 425 nm was obtained from the device. The
intensity of EL light emission was almost in proportional to a
current density. The maximum light emission efficiency of the
device was 0.11 cd/A.
[0623] Furthermore, the voltage when the brightness exhibited 1.0
cd/m.sup.2 was 3.84 V.
Comparative Example 4
Preparation of Solution
[0624] Polymer compound P-4 obtained above was dissolved in toluene
to prepare a toluene solution of a polymer concentration of 1.8 wt
%.
Preparation of EL Device
[0625] An EL device was prepared in substantially the same manner
as in Example 12 except that the toluene solution obtained above
was used. The rotation number during spin coating at this time was
2400 rpm and the thickness of the obtained film was 76 nm.
Performance of EL Device
[0626] When voltage was applied to the obtained device, EL light
emission having a peak at 460 nm was obtained from the device. The
intensity of EL light emission was almost in proportional to a
current density. The maximum light emission efficiency of the
device was 0.35 cd/A.
[0627] Furthermore, the voltage when the brightness exhibited 1.0
cd/m.sup.2 was 3.96 V.
TABLE-US-00003 TABLE 3 Example Example Comparative Comparative 12
13 Example 3 Example 4 Polymer compound P-1 P-5 P-10 P-4 Light
emission 0.58 0.59 0.11 0.35 efficiency (cd/A) Voltage (V) at the
3.44 3.48 3.84 3.96 time of 1.0 cd/m.sup.2
Example 14
Preparation of Solution
[0628] Polymer compound P-9 obtained above was dissolved in xylene
to prepare a xylene solution of a polymer concentration of 1.5 wt
%.
Preparation of EL Device
[0629] An EL device was prepared in substantially the same manner
as in Example 12 except that the xylene solution obtained above was
used. The rotation number during spin coating at this time was 2000
rpm and the thickness of the obtained film was 71 nm.
Performance of EL Device
[0630] When voltage was applied to the obtained device, EL light
emission having a peak at 435 nm was obtained from the device. The
intensity of EL light emission was almost in proportional to a
current density. The maximum light emission efficiency of the
device was 1.08 cd/A.
[0631] Furthermore, the voltage when the brightness exhibited 1.0
cd/m.sup.2 was 3.53 V.
TABLE-US-00004 TABLE 4 Comparative Example 14 Example 4 Polymer
compound P-1 P-4 Light emission efficiency (cd/A) 1.08 0.35 Voltage
(V) at the time of 1.0 cd/m.sup.2 3.53 3.96
Example 15
Preparation of Solution
[0632] Polymer compound P-7 obtained above was dissolved in xylene
to prepare a xylene solution of a polymer concentration of 1.5
wt
Preparation of EL Device
[0633] An EL device was prepared in substantially the same manner
as in Example 12 except that the xylene solution obtained above was
used. The rotation number during spin coating at this time was 1200
rpm and the thickness of the obtained film was 77 nm.
Performance of EL Device
[0634] When voltage was applied to the obtained device, EL light
emission having a peak at 450 nm was obtained from the device. The
intensity of EL light emission was almost in proportional to a
current density. The maximum light emission efficiency of the
device was 0.12 cd/A.
Example 16
Preparation of Solution
[0635] Polymer compound P-8 obtained above was dissolved in xylene
to prepare a xylene solution of a polymer concentration of 1.5 wt
%.
Preparation of EL Device
[0636] An EL device was prepared in substantially the same manner
as in Example 12 except that the xylene solution obtained above was
used. The rotation number during spin coating at this time was 1200
rpm and the thickness of the obtained film was 89 nm.
Performance of EL Device
[0637] When voltage was applied to the obtained device, EL light
emission having a peak at 480 nm was obtained from the device. The
intensity of EL light emission was almost in proportional to a
current density. The maximum light emission efficiency of the
device was 1.72 cd/A.
INDUSTRIAL APPLICABILITY
[0638] The polymer compound of the present invention has effects
such as high charge injectability and transportability, and high
light emission efficiency. When a side chain has a hole
injection/transport group, the energy of the highest occupied
molecular orbital (HOMO) increases, with the result that hole
injectability and hole transportability improve, increasing light
emission efficiency. When a side chain has an electron
injection/transport group, the energy of the lowest unoccupied
orbital (LUMO) decreases, with the result that electron
injectability and electron transportability improve, increasing
light emission efficiency. When a side chain has a light-emitting
group, it is expected that the light emission efficiency increases
or light having a different wavelength from that of the main chain
is emitted.
[0639] When a polymer compound whose main chain has electron
transportability and side chain has a hole injection/transport
group, a new function can be added without inhibiting the electron
transportability of the main chain and the transportability of
electrons and holes can be controlled. When a polymer compound
whose main chain has electron transportability and side chain has a
light-emitting group, light having a different wavelength from that
of the main chain can be emitted. Furthermore, when a
light-emitting group having high efficiency is used, the light
emission efficiency can be also improved. When a polymer compound
whose main chain has electron transportability and side chain has
an electron injection/transport group, the electron
transportability of the main chain can be improved.
[0640] As mentioned above, by separating the function of the side
chain from that of the main chain, a function can be added without
inhibiting the function of the main chain, with the result that
high performance of the polymer compound can be expected.
[0641] Therefore, the polymer LED containing a polymer compound
according to the present invention can be used as a curved or
planar light source for a backlight of a liquid crystal display or
illumination and in a segment type display device and a flat panel
display of dot matrix.
* * * * *