JPH11283750A - Organic eletroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow an element to have low voltage application, high luminance, a long service life and defect-free quality by containing a polymer having a positive hole transporting unit containing three or more aromatic rings and a dopant capable of oxidizing the positive hole transporting unit in a positive hole injection transporting band. SOLUTION: It is preferable that a polymer is a compound that is expressed by a formula I and has a positive hole transporting unit selected from diamine, triarylamine oligomer, thiophene oligomer, arylenevinylene oligomer and styrylamine and a dopant is metal halide, Lewis acid, organic acid, or salt of arylamine and metal halide or Lewis acid, in particular, a compound expressed by a formula IV. In the formula, Ar<1-4> each represent an arylene group of C6-30 ; Ar<5> ,<6> each represent an alkyl group of C1-30 or the like; G represents a single bond, alkylene group or the like of C5-30 ,-O-or-S-, or are expressed by formulas II or III (Ar<7> represents an arylene group and Ar<8-10> each represent an aryl group of C6-30 ); (p)=0 or 1; (q)=0.1 or 2; X represents a non-conjugate spacer group; and (n) represents an average degree of polymerization.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electroluminescence device, and more particularly, to an organic electroluminescence device capable of achieving low voltage, high luminance, long life and no defect.

[0002]

2. Description of the Related Art An electroluminescent device utilizing electroluminescence (hereinafter referred to as "E
L ". ) Is self-luminous and has high visibility.
In addition, since it is a completely solid-state element and has characteristics such as excellent impact resistance, it is attracting attention for use as a light-emitting element in various display devices. This EL element includes an inorganic EL element using an inorganic compound as a light-emitting material and an organic EL element using an organic compound. Among them, an organic EL element can significantly reduce the applied voltage. Since it is easy to reduce the size, consumes little power, can emit light in a plane, and can easily emit light in three primary colors, it has been researched and developed as a next-generation light-emitting element. This organic E
The structure of the L element is based on the structure of an anode / organic light emitting layer / cathode and provided with a hole injection / transport layer or an electron injection layer as appropriate, for example, anode / hole injection / transport layer / organic light emitting layer / Cathode and those having a configuration such as anode / hole injection / transport layer / organic light emitting layer / electron injection layer / cathode are known. By the way, as the material of the hole injection layer, organic low molecular weight compounds and oligomers have been conventionally used, but these have low heat resistance, and their improvement has been demanded. Attempts have also been made to improve heat resistance using polymers, but in this case,
The hole mobility was 10 ⁻⁵ cm ² / V · sec or less, and the resistance of the hole injection layer was a problem. Further, attempts have been made to use a mixture of a polymer and an organic low-molecular-weight compound. In this case, too, the hole injection layer has a conductivity of 10 ^-10 S · c.
m ⁻¹ or less, and the resistance was still a problem.

[0003] On the other hand, WO 95/24056 discloses that
An organic EL device using an all-conjugated polymer for the hole injection layer is disclosed. The all-conjugated polymer is, for example, polyaniline, poly 3,4-ethylene-dioxythiophene. Further, as an element having a similar configuration, there is disclosed an element in which a polyaniline layer is provided on an anode, and a light emitting layer and a cathode are sequentially formed thereon (see International Publication 9).
7/32452). In these devices, the applied voltage can be lowered and the efficiency can be improved, but there are the following problems. (1) Since the material of the hole injection layer is an all-conjugated polymer, it shows strong color and is inferior in transparency.
When the thickness is 50 nm or more, the light transmittance is reduced by 30% or more. Therefore, since the hole injection layer cannot be thickened, it is not possible to sufficiently cover the projections and the anode end present on the anode, and it is easy for defects to occur on the light emitting surface of the element, and leaks and short circuits are likely to occur, In the case of an XY matrix type display element, a crosstalk defect was easily generated.

(2) An all-conjugated polymer is actually an aggregate of various conductive units, and the effective length of the conjugated system is dispersed. This is because the energy level of the unit for transporting holes is reduced. Dispersion was meant, and thus the level of trapping holes could not be essentially avoided. Therefore, the hole mobility, which is the hole mobility, is 10 ⁻⁵ cm ² / V.
・ Lower than seconds. For this reason, when all conjugated polymers are used for the hole injection layer, the resistance of the hole injection layer becomes a problem. In particular, when the emission of high-intensity pulsed light is required, momentarily ^{10mA / cm 2 ~1A / cm 2} , as the case 1k
It is necessary to supply a pulse current up to A / cm ² . However, when the hole mobility is 10 ⁻⁵ cm ² / V · sec or less, there is a problem that a voltage drop occurs in the hole injection layer due to resistance, and the voltage of the device increases. This is because of the so-called space-limited current phenomenon. To avoid this, it is necessary to improve the hole mobility. was there. On the other hand, US Pat. No. 3,995,299
The document discloses the use of an amorphous polymer containing a strong electron-withdrawing substance as the hole injection zone.
However, the disclosed amorphous polymer is limited to polyvinyl carbazole, which has two aromatic rings as side chains and does not have a π-conjugated system. This means that the overlap of the π electron clouds between the hole transport units is small, the hole mobility is low, and there is the same problem as the above-mentioned all conjugated polymer. Furthermore, since the π-conjugated system is not spread, the ionization energy is as high as 5.8 eV, which makes it difficult to oxidize, the conductivity is as low as 10 ⁻⁸ S · cm ⁻¹ or less, and holes are hardly injected from the anode. There was a problem, and improvement was required.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic EL device which can achieve a low voltage, a high luminance, a long life, and no defect under such circumstances. Is what you do.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to develop the above-mentioned organic EL device having excellent performance. As a result, a hole was formed between the anode and the cathode from the anode side. In an organic EL device in which an injection transport zone and a light emission zone are sequentially provided, a polymer having a hole transport unit having a specific structure and a dopant capable of oxidizing the hole transport unit are used as the hole injection transport zone. It has been found that the object can be achieved by using the one contained. The present invention has been completed based on such findings. That is, the present invention provides an organic EL device in which a hole injecting and transporting zone and a light emitting zone are sequentially provided from an anode side between an anode and a cathode, wherein the hole injecting and transporting band has three or more aromatic rings. It is intended to provide an organic EL device comprising at least a polymer having a hole transporting unit containing the same and a dopant capable of oxidizing the hole transporting unit.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The organic EL device of the present invention has a structure in which a hole injection / transport zone and a light emission zone are sequentially provided between an anode and a cathode from the anode side. In the hole injection transport zone, the polymer used together with the dopant,
It contains a hole transporting unit containing three or more aromatic rings, and since the hole transporting unit is independent,
The effect is that the dispersion of the energy level is small and the hole mobility is large. For example, electric field intensity of 1 × 10 ⁵ to 1 × 10 ⁶ V
/ Cm ² · sec, a hole mobility of about 10 ^-4 cm ² / V · sec can be realized. Further, since the hole injecting / transporting zone contains a dopant capable of oxidizing the hole transporting unit, (1) a part of the hole transporting unit is oxidized to generate holes, and The conductivity of the injection transport zone is 10
^-10 S · cm ⁻¹ to 10 ³ S · cm ⁻¹ ,
(2) Due to the oxidized hole transporting unit, the overlapping of the π electron clouds is increased, and the effect that the hole mobility is further improved as compared with before the doping is exhibited.

According to the effect (1), the anode and the hole are injected.
The energy barrier between the transport zones is reduced, resulting in better holes
Infusion can be effected. Conventionally contains dopant
Hole injection transport zones have been used, but the equation ΔE = I_P-W_F (However, I_PIs the ionization energy of the hole injection transport zone
And W_FIs the work function of the anode. D)
The energy barrier (ΔE) is about 0.2 eV to 0.8 eV.
Was. In order to inject holes beyond this ΔE, the interface
Requires a strong electric field, which causes the device to operate at a higher voltage.
I was In contrast, in the present invention, the hole injection transport
Since holes are generated in the band and become conductive, ΔE is effectively
Is reduced to 0.1 eV or less, and a sharp increase in hole injection
The effect is obtained. This is due to the hole injection transport zone
The hole carrier moves to the anode and a high electric field is automatically generated.
It is thought that the energy barrier is reduced
You. That is, in the present invention, the hole carrier is positive.
Move to the poles, the negatively charged dopant remains at the interface,
As a result, an electric double layer potential is generated at the interface, and ΔE is
It is considered that this potential is reduced. In addition,
This means that I _PIt does not mean that you change
Absent. Energy barrier by charge transfer as described above
Is considered to be reduced.

Further, in the prior art, in addition to such a hole injection limitation, a space limitation current has been a problem as an element of the bulk limitation. This space limiting current is expressed by the relational expression I = 9 / 8ε · ε ₀ · μ · V ² / d ³ (where ε is the relative permittivity, ε ₀ vacuum permittivity, μ is the hole mobility, and d is the hole The film thickness V of the injection / transport zone is a voltage applied to the hole injection / transport zone.), And is represented by a current I due to holes which can flow to the element at the maximum. Here, μ = 10
Considering an average value of ^-4 cm ² / V · sec, ε = 3.0,
When d = 200 nm, I = 1.5 × 10 ² mA / c
To flow m ² , it is necessary to apply a voltage of 10 V to the hole injecting and transporting band, and when d = 400 nm,
It is necessary to apply a voltage of ^81/2 times 10V.
Therefore, even in the case of using a relatively good hole injection / transport zone having a hole mobility of 10 ⁻⁴ cm ² V · sec, a large applied voltage was required in the related art. This means that the pulse
This was a major problem when injecting a current of 100 mA / cm ² or more. Furthermore, when a hole injection / transport zone having a large film thickness is used, a larger voltage needs to be applied, resulting in an increase in power consumption.

On the other hand, in the present invention, the effect of (2) has the effect of improving the mobility and the effect of reducing the voltage. Further, the effect of the space-limited current can be reduced by the effect of the conductivity of (1), and the applied voltage can be reduced. As a result, the thickness of the hole injection / transport zone can be increased. For example, in WO 95/24056, a hole injection / transport zone having a thickness of 120 to 150 nm is used in Example 1 because the thickness cannot be increased as described above. As a result, the irregularities and projections of the anode could not be sufficiently covered, and it was difficult to avoid defects of the element, and defects were likely to occur in the display device. On the other hand, in the present invention, the hole injection / transport zone can be formed to have a thickness of preferably 200 nm or more, more preferably 400 nm or more, so that the above-described defect of the element can be avoided.

In the organic EL device of the present invention, the polymer used in the hole injecting and transporting zone has a hole transporting unit containing three or more aromatic rings.
One type or two or three types may be introduced, but the hole transport units are not connected by a conjugated system. Further, this hole transporting unit has an extremely small energy dispersion, preferably has an energy dispersion of 0.2 eV or less, and when connected in a conjugated system, becomes a conjugated polymer compound and has a large energy dispersion. And as a result,
A trap is generated, resulting in a decrease in hole mobility. That is, the polymer used in the present invention is completely different from all conjugated polymers conventionally used. The hole transport unit is a group having a hole-transporting compound structure, and is not particularly limited as long as it has such a hole-transporting compound structure. can do. As the hole transporting unit, for example, a unit derived from a compound selected from diamine, triarylamine oligomer, thiophene oligomer, arylene vinylene oligomer and styrylamine is preferably exemplified.

For good hole transport, the hole transporting units must not be connected in a conjugated system and must be electrically independent. In the present invention, the preferred ionization energy of the hole transport unit is
5.7 eV or less. When the ionization energy is 5.7 eV or less, the hole transport unit is easily oxidized by the dopant used in combination, and holes are easily injected by the anode into the hole injection / transport zone using this polymer. can do. Here, the fact that holes can be easily injected means that 20 mA / cm 2 is applied under an electric field of 3 × 10 ⁵ V / cm.
^This means that ^two or more currents can be injected. This can be easily determined by a test element having a configuration of anode / hole injection / transport zone / emission zone / cathode. In the device of the present invention, preferred examples of the polymer used in the hole injecting and transporting zone are such that the hole transporting unit is connected by a non-conjugated spacer group, and conjugation between the hole transporting units is negligible. . This makes it possible to prevent the conjugate chain length from being dispersed, resulting in hole trapping and a decrease in hole mobility.

As the non-conjugated spacer group, those which are inactive in transporting holes are preferred. Examples of such non-conjugated spacer groups include ester groups, ether groups, carbonate groups, Urethane group,
An amide group, a sulfone group, a ketone group and the like can be preferably mentioned. As another non-conjugated spacer group, for example, a compound represented by the general formula (III)

[0014]

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And the group represented by the formula: In the general formula (III), r, s and t are 0 or an integer of 1 or more, and the total is 1 or more. D ¹ and D ³ are
Each independently represents an ether group, a carbonate group, an ester group, an amide group, a urethane group, an alkylene group having 1 to 30 carbon atoms, a cycloalkylene group having 5 to 30 carbon atoms, and 1 carbon atom;
A halogenated alkylene group having from 30 to 30 or an aryl-substituted alkylene group having from 7 to 30 carbon atoms. On the other hand, D ² is a group represented by the general formula (IV) other than the groups exemplified as D ¹ and D ³ above.

[0016]

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(U is 0 or an integer of 1 or more). Here, Ar and Ar ′ are each independently a substituted or unsubstituted arylene group having 6 to 30 carbon atoms. Examples of the substituent include an aryl group having 6 to 24 carbon atoms, an alkyl group having 1 to 24 carbon atoms, and 7 to 2 carbon atoms.
4, an aralkyl group having 6 to 24 carbon atoms, an aryloxy group having 6 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, a mono- or dialkylamino group having 1 to 24 carbon atoms in the alkyl group, and a 6 to 24 carbon atom in the aryl group. Mono- or diarylamino groups,
Examples thereof include a mono- or di-alkylarylamino group having 7 to 24 carbon atoms in the alkylaryl group. E is an alkylene group having 1 to 30 carbon atoms, a cycloalkylene group having 5 to 30 carbon atoms, a halogenated alkylene group having 1 to 30 carbon atoms, or an aryl-substituted alkylene group having 7 to 30 carbon atoms.
Further, the non-conjugated spacer group in the polymer may be composed of an electron transport unit. In this case, the non-conjugated unit is a unit which is inactive in hole transporting in which the hole transporting unit is dispersed. As the non-conjugated spacer group, preferable electron transporting units include, for example, oxazole derivatives, oxadiazole derivatives, Examples thereof include divalent groups derived from phthalimide derivatives and perylene derivatives. Specifically, the general formula (V)

[0018]

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Oxazole and oxadiazo represented by
Or a divalent group derived from the derivative thereof. This
Where R¹And R^TwoAre each independently 6 to 30 carbon atoms
Is an arylene group or an alkylene group having 1 to 30 carbon atoms.
, Z¹And Z^TwoAre each independently -CR ^Three= Or-
N =, Z^ThreeIs -O-, -NR^Four-Or -SiR^FiveR⁶−
It is. R^Three~ R⁶Are ants each having 6 to 30 carbon atoms
Or an alkyl group having 1 to 30 carbon atoms. Also,
This non-conjugated spacer group is a σ-conjugated spacer group.
Is also included. Assume that the hole transport units are connected in a sigma-conjugate system
But without losing its individual independence, as an independent unit
It works. With a preferred σ-conjugated spacer group
The spacer group of the Si bond, specifically, the general formula (V
I)

[0020]

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(V is an integer of 1 or more). In the general formula (VI), R ⁷
And R ⁸ are each independently an alkyl group having 1 to 30 carbon atoms or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. Examples of the substituent of the aryl group include C1 to C2.
4 alkyl groups or alkoxy groups. In the device of the present invention, examples of the polymer used in the hole injecting and transporting band include a copolymer containing a hole transporting unit and a non-conjugated spacer group, and a hole transporting unit and an electron transporting unit. Copolymers are particularly preferred. Further, a copolymer utilizing the fact that the electron transport unit is inactive for hole transport and using this as a non-conjugated spacer group can also be preferably mentioned. Further, a copolymer containing a hole transport unit and a σ-conjugated spacer group can also be used. Specific examples of such a polymer include the following. (1) A polymer containing a unit derived from a diamine or triarylamine oligomer as a hole transporting unit. For example, a compound represented by the general formula (VII):

[0022]

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A polymer or copolymer having a repeating unit represented by the formula: and the unit or this unit and the electron transporting unit are linked via an ester, ether, carbonate, urethane, amide, sulfone or ketone group, etc. And a copolymer in which the unit represented by the general formula (VII) and the σ-conjugated spacer group represented by the general formula (VI) are alternately linked. General formula (VII)
In the formula, Ar ^{1 to} Ar ⁴ each independently represent a substituted or unsubstituted arylene group having 6 to 30 carbon atoms. A
r ⁵ and Ar ⁶ each independently represent an alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. Here, examples of the substituent of the arylene group and the aryl group include an alkyl group or an alkoxy group having 1 to 24 carbon atoms. On the other hand, G is a single bond, having 5 to 5 carbon atoms.
An alkylene group having 30 carbon atoms, a cycloalkylene group having 5 to 30 carbon atoms, an arylene group having 6 to 30 carbon atoms, -O-, -S-
Or

[0024]

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Is a group represented by G may have a substituent. Examples of the substituent include an alkyl group having 1 to 24 carbon atoms, an aryl group having 6 to 24 carbon atoms, and a C 7 to 2 carbon atom.
4, an aralkyl group having 1 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, an aryloxy group having 6 to 24 carbon atoms, a mono- or dialkylamino group having 1 to 24 carbon atoms in the alkyl group, and a 6 to 24 carbon atom in the aryl group. Examples thereof include a mono- or diarylamino group, and a mono- or dialkylarylamino group having 7 to 24 carbon atoms in an alkylaryl group.
Ar ⁷ is an arylene group having 6 to 30 carbon atoms, Ar ^{8 to} Ar
¹⁰ is an aryl group having 6 to 30 carbon atoms,
r ^{7 to} Ar ¹⁰ may be substituted with the same substituents as those described above for G. p is 0, 1 or 2. Such polymers include, for example, those of the formula (I)

[0026]

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[Ar ^{1 to} Ar ⁶ and G are the same as above. P is 0, 1 or 2, and q is 0, 1 or 2.
And X represents a non-conjugated spacer group. In addition, n shows an average degree of polymerization. The carbonate-based copolymer represented by the following formula (1) is preferred. Particularly preferred carbonate copolymers are represented by the following formula:

[0028]

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(For the molecular weight, for example, Mn = 200
00, Mw = 70000. ) Can be exemplified. (2) A polymer containing a unit derived from a thiophene oligomer as a hole transporting unit.

[0030]

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A polymer or copolymer having a repeating unit represented by the formula: and this unit or this unit and an electron transporting unit are linked via an ester, ether, carbonate, urethane, amide, sulfone or ketone group, Further, a copolymer in which the unit represented by the general formula (VIII) and the σ-conjugated spacer group represented by the general formula (VI) are alternately linked is exemplified. General formula (VII
In I), a, b and c each represent an integer of 0 to 9, and their total is at least 3. R ^{9 to} R
¹⁴ is a hydrogen atom, a linear or branched alkyl group or alkoxy group having 1 to 15 carbon atoms,
^{In each of 9} and R ¹⁰ , R ¹¹ and R ¹² and R ¹³ and R ¹⁴ , one of them is not a hydrogen atom. (3) A polymer containing a unit derived from an arylene vinylene oligomer as a hole transporting unit. For example, general formula (IX)

[0032]

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A polymer or copolymer having a repeating unit represented by the formula: and this unit or this unit and an electron transporting unit are linked via an ester, ether, carbonate, urethane, amide, sulfone or ketone group, Further, a copolymer in which the unit represented by the general formula (IX) and the σ-conjugated spacer group represented by the general formula (VI) are alternately linked is exemplified. In the general formula (IX), R ^{15 to} R ²⁰ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 30 carbon atoms, and a carbon atom having 6 to 2 carbon atoms.
4, an aralkyl group having 7 to 24 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, an aryloxy group having 6 to 24 carbon atoms, an alkylthio group having 1 to 30 carbon atoms, and an alkyl group having 1 to 1 carbon atoms. 30 represents a mono or dialkylamino group, an arylthio group having 6 to 24 carbon atoms, a mono or diarylamino group having 6 to 24 carbon atoms, a nitro group or a cyano group. d is an integer of 1 to 500. (4) A polymer containing a unit derived from styrylamine as a hole transporting unit. For example, general formula (X)

[0034]

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A polymer or copolymer having a repeating unit represented by the formula: and this unit, or this unit and an electron transporting unit are linked via an ester, ether, carbonate, urethane, amide, sulfone or ketone group, Further, a copolymer in which the unit represented by the general formula (X) and the σ-conjugated spacer group represented by the general formula (VI) are alternately linked is exemplified. In the general formula (X), Ar ^{11 to} Ar ¹⁴ each independently represent a substituted or unsubstituted arylene group having 6 to 30 carbon atoms. Ar
¹⁵ and Ar ¹⁶ each independently represent a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. R ²¹ and R ²² are
Each independently represents a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. Here, examples of the substituent of the arylene group and the aryl group include an alkyl group or an alkoxy group having 1 to 24 carbon atoms. e is 0 or 1. Also, the broken line
It shows that you may couple | bond with a single bond or a C1-C6 alkylene group. The general formula (XI)

[0036]

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Having a repeating unit represented by
Position, or this unit and the electron transport unit are esters, ethers
, Carbonate, urethane, amide, sulfone or ketone
Polymers or copolymers linked through ton groups, etc.
And a unit represented by the above general formula (XI)
The σ-conjugated spacer group represented by the general formula (VI)
And other linked copolymers. In general formula (XI)
And Ar¹⁷~ Ar^{twenty one}Is Ar of the above general formula (X)¹¹
~ Ar ¹⁴And Ar^{twenty two}And Ar^{twenty three}Is the general formula
Ar of (X)^FifteenAnd Ar¹⁶Is the same as Also, R^{twenty three}Passing
And R^{twenty four}Is R of the general formula (X)^{twenty one}And R^{twenty two}Is the same as
f is 0 or 1, and the dashed line is a single bond or a group having 1 to 6 carbon atoms.
It shows that you may couple | bond with an alkylene group. The present invention
In addition, these polymers may be used alone, and two or more kinds may be used.
The above may be used in combination.

In the organic EL device of the present invention, hole injection
The dopant used in the transport zone together with the polymer is
Oxidizing the hole transport units contained in the polymer, thereby
Has the effect of imparting conductivity to the hole injection transport zone.
It is. As this conductivity, the conductivity is preferably
10^-Ten-10^ThreeS ・ cm^-1And also the holes
The hole concentration generated in the injection transport zone is 10¹²-10^Two
cm^-3It is preferred that In the present invention, the hole injection
The concentration of the dopant in the transport zone is 10^-3
The range of about 70 mol% is preferable. As this dopant
Is preferably an oxidizing agent, particularly a metal halide,
Lewis acids, organic acids, arylamines and metal halides
Or salts with Lewis acids are preferred. The above metal halide
And Lewis acids are preferably FeCl_Three, AlC
l _Three, SbCl_Five, AsF_Five, BF_ThreeEtc.
You. As the organic acid, for example, a compound represented by the general formula (XII)

[0039]

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And the like. In the general formula (XII), A is an acid group such as a sulfonic acid group, a phosphoric acid group, a boric acid group and a carboxylic acid group. R is carbon number 1
20 alkyl groups, alkoxy groups, alkylthio groups, alkoxyalkyl groups having 2 to 20 carbon atoms, alkylthioalkyl groups, alkenyl groups, cycloalkyl groups having 5 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms, and 7 carbon atoms ~ 20
And a heterocyclic group such as a pyridyl group, a quinolyl group, a furanyl group, a pyrrolyl group, and a thienyl group, or a halogen atom, a nitro group, a cyano group, and an epoxy group. m is an integer of 0 to 5, and when m is 2 or more, a plurality of Rs may be the same or different. Further, another example of the organic acid is a polymer acid. This polymer acid has an acid group A in the general formula (XII) in a polymer, and examples thereof include sulfonated polystyrene, sulfonated polyethylene, and sulfonated polycarbonate. Acrylic acid polymers can also be used. Further, examples of the salt of an arylamine with a metal halide or a Lewis acid include compounds represented by general formula (XIII):

[0041]

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The salts represented by In the general formula (XIII), L is a metal halide or Lewis acid, for example, SbCl ₅ , BF ₃ , AsF ₅ , AlC
l ₃ and FeCl ₃ . X ^- is preferably a halogen ion. Ar ^{24 to} Ar ²⁶ are each independently a substituted or unsubstituted aromatic group or heterocyclic group having 5 to 30 carbon atoms. Preferred substituents include a halogen atom, a nitro group, a cyano group, an alkyl group having 1 to 24 carbon atoms, an aryl group having 6 to 24 carbon atoms, and a 7 to 24 carbon atoms.
An aralkyl group, an alkoxy group having 1 to 24 carbon atoms, an aryloxy group having 6 to 24 carbon atoms, a mono- or dialkylamino group having 1 to 24 carbon atoms in an alkyl group, and a mono- or dialkylamino group having 6 to 24 carbon atoms in an aryl group. Or a diarylamino group. Preferred examples of the dopant include those represented by the formula (II)

[0043]

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Compounds represented by the following formulas can be mentioned.
In the present invention, the above-mentioned dopants may be used alone or in combination of two or more. In the organic EL device of the present invention, the thickness of the hole injection / transport zone containing the polymer and the dopant is preferably 200 nm or more, and particularly preferably in the range of 400 to 2000 nm.
The method for forming the hole injecting and transporting zone is not particularly limited, and various conventionally known methods can be used. However, it is advantageous to form the hole injecting and transporting zone by spin coating.
The organic EL device of the present invention is provided with a hole injection transport zone and a light emission zone containing at least the polymer and the dopant in this order from the anode side between the anode and the cathode. It can realize low voltage, high luminance, long life and no defect.

FIG. 1 is a cross-sectional view showing the structure of an example of the organic EL device of the present invention. The organic EL device has a structure in which a hole injection / transport zone 2, a light emitting zone 3 and a cathode 4 are sequentially laminated on an anode 1. Show.
The light emitting band essentially includes an organic light emitting layer, and may have a hole transport layer and an electron injection layer as needed. That is, the configuration of the light emitting band includes, for example, from the anode side to the cathode side, (1) organic hole transport layer / organic light emitting layer (2) organic light emitting layer / electron injection layer (3) inorganic hole transport layer / organic light emitting layer. Layer (4) Organic hole transport layer / organic light emitting layer / organic electron injection layer.

In the present invention, it is particularly preferable to provide a hole transport layer, whether organic or inorganic, between the organic light emitting layer and the hole injection / transport zone. The role of the hole transport layer is to (1) prevent the excited state formed by recombination in the light emitting layer from coming into contact with the hole injection / transport band and quenching;
(2) To prevent electrons from passing from the light emitting layer to the hole injecting / transporting zone, thereby increasing recombination efficiency. The material of the organic hole transport layer is not particularly limited, and may be appropriately selected from various known materials used for the organic hole transport layer in an organic EL device, depending on the situation. Can be used. As such a material, preferably, a diamine compound, a triarylamine compound, a triarylamine oligomer, a triarylamine dendrimer and the like are exemplified. The organic hole transport layer preferably contains an oxidizing dopant in a proportion of 0.2% by weight or less. On the other hand, the material of the inorganic hole transport layer is not particularly limited, and may be appropriately selected from various known materials used for the inorganic hole transport layer in an organic EL device in accordance with the circumstances. Can be used.
Examples of such a material include transparent inorganic oxides, inorganic carbides, and inorganic nitrides, specifically, α-C, α-Si
C, α-SiN, α-SiON and the like. Another preferred example is RuO _x , MoO _x , VO _x
(1 <x <2).

The hole transporting layer comprises the above hole transporting material,
For example, vacuum deposition, spin coating, casting, LB
It can be formed by thinning by a known method such as a method. The thickness of the hole transport layer is not particularly limited, but is usually about 5 nm to 5 μm. The hole transport layer may have a single-layer structure composed of one or more of the above materials, or may have a laminated structure composed of a plurality of layers having the same composition or different compositions. The organic light emitting layer in the organic EL device of the present invention can (1) inject holes from the anode through the hole injecting layer transport zone when an electric field is applied;
In addition, an injection function capable of injecting electrons from the cathode or the electron injection layer, (2) a transport function of moving injected charges (electrons and holes) by the force of an electric field, and (3) a recombination of electrons and holes. A field is provided inside the light-emitting layer, and the light-emitting layer has a light-emitting function and the like for connecting this to light emission. However, there may be a difference between the ease of injecting holes and the ease of injecting electrons,
The transport function represented by the mobility of holes and electrons may be large or small, but one having a function of transferring one of the charges is preferable. There is no particular limitation on the type of light emitting material used in the organic light emitting layer, and a known organic light emitting material in an organic EL device can be used. Specific examples of such an organic light emitting material include the following compounds depending on a desired color tone.

First, in order to obtain emission in an ultraviolet region or a purple region, a para-polyphenylene-based material is preferable. The phenyl or phenylene group of the para-polyphenylene compound has one or two substituents such as an alkoxy group, a hydroxyl group, a sulfonyl group, a carboxyl group, an alkoxycarbonyl group, an amino group, a dimethylamino group, and a diphenylamino group. The above may be introduced. Examples of such para-polyphenylene compounds include p-
Quarter phenyl; 3,5,3 ', 5'-tetra-t
-Butyl-p-quinkphenyl; 3,5,3 ', 5'
-Tetra-t-butyl-p-sexiphenyl and the like. Next, in order to obtain blue to green light emission, for example, benzothiazole-based, benzimidazole-based, benzoxazole-based fluorescent whitening agents, metal-chelated oxinoid compounds, and styrylbenzene-based compounds can be used. Further, aromatic dimethylidin compounds (European Patent No. 388768, JP-A-3-23197)
No. 0) can also be preferably used. Examples of the aromatic dimethylidin compound include:
1,4-phenylenedimethylidin; 4,4′-biphenylenedimethylidin; 2,5-xylylenedimethylidylidine; 2,6-naphthylenedimethylidin; 1,4-p
-Telephenylenedimethylidin; 4,4'-bis (2,2-di-t-butylphenylvinyl) biphenyl (DTBPVBi); 4,4'-bis (2,2-diphenylvinyl) biphenyl (DPVBi) and the like And their derivatives.

Further, general formula (XIV) (JQ) ₂ -Al-OZ (XIV) described in JP-A-5-258882 (wherein Z represents a benzene ring A hydrocarbon group containing 6 to 24 carbon atoms, OZ represents a phenolate ligand, Q represents a substituted 8-quinolinolate ligand, and J represents an aluminum atom having more than two substituted 8-quinolinolate ligands bonded thereto. Represents an 8-quinolinolate ring substituent which is selected so as to sterically hinder the reaction. Examples of this compound include bis (2-methyl-8-
(Quinolinolate) (p-phenylphenolate) aluminum (III), bis (2-methyl-8-quinolinolate) (1-naphtholate) aluminum (III), and the like. In addition, in order to obtain highly efficient mixed light emission of blue and green, a material obtained by adding a dopant to the above-mentioned light emitting material as a host (Japanese Patent Application Laid-Open No. 6-9953) can be used. Examples of the dopant include fluorescent dyes in a blue region or a green region, specifically, coumarin-based fluorescent dyes or fluorescent dyes similar to those used as the above-mentioned host. In particular, a luminescent material having a distyrylarylene skeleton as a host, preferably DPVBi, and a material having a diphenylaminovinylarylene skeleton as a dopant, preferably 4,4′-bis [4- (N, N
-Diphenylamino) styryl] benzene (DPAV
Combinations with B) are preferred.

As a method of forming a light emitting layer using the above materials, for example, a vapor deposition method, a spin coating method, a casting method,
Although it can be formed by thinning by a known method such as the LB method, it is particularly preferably a molecular deposition film. Here, the molecular deposition film refers to a thin film formed by depositing the compound from a gaseous state or a film formed by solidifying the compound from a molten state or a liquid state.
Normally, this molecular deposited film can be distinguished from a thin film (molecule accumulation film) formed by the LB method by a difference in a cohesive structure and a higher-order structure and a functional difference resulting therefrom. Further, as described in JP-A-57-51781, this light-emitting layer is prepared by dissolving the light-emitting material together with a binder such as a resin in a solvent to form a solution, and then spin-coating the solution. It can be formed as a thin film. The thickness of the light emitting layer thus formed is not particularly limited and can be appropriately selected depending on the situation.
Usually, it is in the range of 5 nm to 5 μm.

The electron injection layer used as needed may have a function of transmitting electrons injected from the cathode to the light-emitting layer, and may be made of a known inorganic or organic compound. Any of them can be selected and used. Examples of materials used for the electron injection layer (hereinafter, referred to as electron injection materials) include heterocyclic tetracarboxylic anhydrides such as nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, naphthalene perylene, carbodiimide, Examples include fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, and oxadiazole derivatives. Also,
A series of electron-transporting compounds described in JP-A-59-194393 are disclosed as materials for forming a light-emitting layer in the publication, but as a result of examination by the present inventors,
It has been found that it can be used as an electron injection material. further,
In the oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as the electron injecting material.

Also, metal complexes of 8-quinolinol derivatives, for example, tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-
Quinolinol) aluminum, tris (2-methyl-8)
-Quinolinol) aluminum, tris (5-methyl-
8-quinolinol) aluminum, bis (8-quinolinol) zinc, and the like, and the central metal of these metal complexes are I
A metal complex replaced with n, Mg, Cu, Ca, Sn, Ga or Pb can also be used as an electron injection material. In addition, metal-free or metal phthalocyanine, or those whose terminals are substituted with an alkyl group, a sulfonic acid group, or the like, can also be preferably used as an electron injection material. In addition, a distyrylpyrazine derivative exemplified as a material for the light emitting layer can be used as an electron injection material, and an inorganic semiconductor such as n-type Si or n-type SiC can also be used as an electron injection material.

This electron injection layer can be formed by forming the above compound by a known thinning method such as a vacuum evaporation method, a spin coating method, a casting method, and an LB method. The thickness of the electron injection layer is not particularly limited, but is usually selected in the range of 5 nm to 5 μm. The electron injection layer may have a single-layer structure composed of one or two or more of these electron injection materials, or may have a laminated structure composed of a plurality of layers having the same composition or different compositions. In the organic EL device of the present invention, it is preferable that the organic EL device is supported by a substrate, and the substrate is not particularly limited, and those conventionally used in organic EL devices, for example, those made of glass or transparent plastic are used. . This organic EL
The anode in the device is an electrode for injecting holes into the device, and has a large work function (4e
V or more) Those using a metal, an alloy, an electrically conductive compound and a mixture thereof as an electrode material are preferably used. Specific examples of such an electrode material include metals such as Au and Cu.
I, ITO (indium tin oxide), SnO ₂ , Z
A conductive transparent material such as nO may be used. This anode is
For example, these electrode materials can be manufactured by forming a thin film by a method such as vacuum evaporation or sputtering. When extracting light emission from this electrode,
It is desirable that the transmittance for light emission be greater than 10%, and the sheet resistance as an electrode is preferably several hundred Ω / □ or less.

Further, although the film thickness depends on the material, it is usually 10 n
m to 1 μm, preferably 50 to 200 nm. On the other hand, the cathode is an electrode for injecting electrons into the device, and has a small work function (4e
V or less) A metal, an alloy, an electrically conductive compound, and a mixture thereof are used as an electrode material. Specific examples of such an electrode material include sodium, sodium-potassium alloy, magnesium, lithium, magnesium /
Copper mixture, a magnesium / silver alloy, aluminum - lithium alloy, Al / Al ₂ O ₃ mixtures, indium, and rare earth metals. This cathode can be produced by forming a thin film of these electrode substances by a method such as vacuum deposition or sputtering. When light is extracted from this electrode, it is desirable that the transmittance for the light emission is greater than 10%, and the sheet resistance of the electrode is preferably several hundred Ω / □ or less.
Further, although the film thickness depends on the material, it is usually 10 nm to 1 μm,
Preferably, it is selected in the range of 50 to 200 nm.

Next, a preferred example for producing the organic EL device of the present invention will be described. First, a thin film made of a desired electrode material, for example, a material for an anode, is formed on an appropriate substrate by 10 nm to 1 μm.
m, preferably in the range of 50 to 200 nm by a method such as vapor deposition or sputtering to form an anode. Next, a thin film made of, for example, a material for a hole injection transport zone, a hole transport layer, an organic light emitting layer, and an electron injection layer is formed thereon. Examples of the method for thinning include a spin coating method, a casting method, and a vapor deposition method. The hole injection / transport zone is preferably formed by a spin coating method. When a vacuum evaporation method is used for thinning the film, the evaporation conditions vary depending on the type of compound used, the target crystal structure of the molecular deposition film, the association structure, and the like.
° C, vacuum degree 10 ^-6 to 10 ^-3 Pa, deposition rate 0.01 to 50
nm / sec, substrate temperature -50 to 300 ° C, film thickness 5 nm to 5
It is desirable to select an appropriate value in the range of μm.

After these layers are formed, a thin film made of a material for a cathode is formed thereon with a thickness of 10 nm to 1 μm, preferably 50 to 1 μm.
A desired organic EL device can be obtained by forming the film to a thickness in the range of 200 nm by, for example, a method such as vapor deposition or sputtering and providing a cathode. Note that, in the production of this EL element, it is also possible to reverse the production order and produce it. When a DC voltage is applied to the organic EL device thus obtained, the anode is connected to +,
When a voltage of about 3 to 40 V is applied with the negative polarity of the cathode, blue light emission can be observed. Also, even if a voltage is applied with the opposite polarity, no current flows and no light emission occurs. further,
When an AC voltage is applied, light is emitted only when the positive electrode becomes + and the negative electrode becomes-. The waveform of the applied alternating current may be arbitrary.

[0057]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Example 1 First, as a hole transporting unit, a formula

[0058]

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The diamine structure represented by the following formula is used as a non-conjugated spacer group,

[0060]

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The group represented by the formula is selected and disclosed in JP-A-5-2327.
According to the method described in JP-A No. 27, the formula (I)

[0062]

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[Polymer represented by (Mn = 20,000, Mw = 70000)] [Ionization energy: 5.5 e
V, measured with a photoelectron spectrometer (RIKEN Keiki AC-1)]. Next, a glass substrate provided with an ITO film having a thickness of 150 nm was prepared, and washed with oxygen plasma for 30 seconds using a plasma washing machine (BP1 manufactured by Samco International). Next, 50 mg of the above polymer and tris (4-bromophenyl) ammonium hexachloroantimonate (TBAHA) 5 were placed on the washed ITO substrate.
mg and a solution prepared by dissolving the resulting compound in 1 ml of dichloromethane was spin-coated at 1,000 rpm.
By heating at 0 ° C. for 1 hour and removing the solvent, a hole injecting / transporting zone having a thickness of 650 nm (measured with a stylus thickness gauge) was formed.

Next, tris (8-hydroxyquinoline) aluminum (Alq) was vacuum-deposited on the hole injecting / transporting zone to a thickness of 50 nm as a material for the light emitting layer.
A magnesium / silver alloy cathode was evaporated to a thickness of 200 nm to produce an organic EL device. With a direct current of 7 V applied using an ITO electrode as an anode and a magnesium / silver alloy electrode as a cathode of the device, current-voltage characteristics were obtained, and luminance and efficiency were measured. Table 1 shows the results. In addition, when an organic EL element is used for a display or a laser, high current injection is required. Therefore,
The voltage required for 250 mA / cm ² current injection was measured. Table 2 shows the results. Example 2 An organic EL device was prepared in the same manner as in Example 1 except that the amount of TBAHA used was changed to 10 mg, and current-voltage characteristics were determined, and luminance and efficiency were measured. Table 1 shows the results. In addition, 250mA
The voltage required for current injection of / cm ² was measured. Table 2 shows the results.

Example 3 An organic EL device was prepared in the same manner as in Example 1, except that the amount of TBAHA used was changed to 0.5 mg. It was measured. Table 1 shows the results. In addition, 250mA
The voltage required for current injection of / cm ² was measured. Table 2 shows the results. Comparative Example 1 An organic EL device was prepared in the same manner as in Example 1 except that TBAHA was not used, and the current-voltage characteristics were determined, and the luminance and efficiency were measured. Table 1 shows the results. In addition, 250 mA / cm
^The voltage required for the current injection of No. ² was measured. The result is
It is shown in the table.

Comparative Example 2 First, Synth. Mec, Vol. 55, p. 3514 (1
993) to produce an all-conjugated polyaniline.
Next, according to the method described in WO 95/24056, the polyaniline and camphor sulfonic acid are contained.
A 5% by weight m-cresol solution was spin-coated on an ITO substrate at a rotation speed of 8000 rpm, and a polyaniline layer serving as an 80 nm-thick hole injection / transport band (camphor sulfonic acid was used as an oxidative dopant). Content). Then, Alq was vacuum-deposited thereon to a thickness of 50 nm, and then a magnesium-silver alloy cathode was
Vapor deposition was performed to a thickness of 0 nm to produce an organic EL device. With respect to this element, the current-voltage characteristics were obtained in the same manner as in Example 1, and the luminance and efficiency were measured. Table 1 shows the results. Further, a voltage required for 250 mA / cm ² current injection was measured. Table 2 shows the results.

Comparative Example 3 An organic EL device was prepared in the same manner as in Example 1 except that polyvinyl carbazole was used instead of the polymer having a diamine structure. Brightness and efficiency were measured. Table 1 shows the results. Further, a voltage required for 250 mA / cm ² current injection was measured. Table 2 shows the results.

[0068]

[Table 1]

[0069]

[Table 2]

It is apparent from Table 1 that the effects of the present invention are extremely large in Examples 1 to 3 as compared with Comparative Example 1. That is, a current of 5 mA / cm ² or more can be injected with an electric field intensity as small as 1 × 10 ⁵ V / cm. In the optimum embodiment 2, a large current exceeding 100 mA / cm ² is a low voltage of 7 V (electric field intensity 1 × 10 ⁵ V / c).
m). Conventionally, a hole injection / transport zone containing no oxidizing dopant has been used.
It can be seen that only a very small current injection of less than 0.1 mA / cm ² could be performed (Comparative Example 1). In the present invention, it was clearly demonstrated that the energy barrier for hole injection was reduced. In the case of Comparative Example 2, a voltage of 7 V (electric field intensity of 3.0 × 10 ⁵ V / cm) was applied at 15 mA / cm 2.
² flows, and according to the present invention (Examples 1 and 2),
Current injectability and efficiency were poor.

Furthermore, in the case of Comparative Example 3, the amount of current injection at the same electric field intensity was small and the efficiency was slightly inferior to that of the present invention. This is because polyvinyl carbazole has a hole transport unit (carbazole) having only two aromatic rings in the side chain and has a large ionization energy of 5.8 eV, so that it is difficult to be oxidized, and the hole carrier concentration is low. The hole mobility is also considered to be low because the overlap of the π electron clouds is small. On the other hand, from Table 2, it can be seen that the battery of the present invention has a very low voltage (7 to 9 V).
It can be seen that a large current can be injected at. On the other hand, the thing of a comparative example is inferior in current injection property. In the device containing no oxidizing dopant of Comparative Example 1, a high voltage is required because of the injection barrier. In addition, polyvinyl carbazole (Comparative Example 3) has a low hole mobility of 10 ⁻⁷ cm ² / V · sec or less and a low hole concentration, so that the injection barrier is large and the resistance is large, so that the voltage is increased. It is thought that. Example 4 In Example 1, a compound represented by the formula

[0072]

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A polymer (ionization energy: 5.2 eV) was produced in the same manner as in Example 1 except that the triarylamine oligomer structure represented by the following formula was selected.
An element was manufactured. With respect to this element, the current-voltage characteristics were obtained in the same manner as in Example 1, and the luminance and efficiency were measured. Table 3 shows the results. Example 5 In Example 1, a compound represented by the formula

[0074]

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A polymer (ionization energy: 5.6 eV) was produced in the same manner as in Example 1 except that the styrylamine structure represented by the following formula was selected, and then an organic EL device was produced. With respect to this element, the current-voltage characteristics were obtained in the same manner as in Example 1, and the luminance and efficiency were measured. Table 3 shows the results. Example 6 In Example 1, a compound represented by the formula

[0076]

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A polymer (ionization energy: 5.6 eV) was produced in the same manner as in Example 1 except that the arylene vinylene oligomer structure represented by the following formula was selected.
An element was manufactured. With respect to this element, the current-voltage characteristics were obtained in the same manner as in Example 1, and the luminance and efficiency were measured. Table 3 shows the results. Example 7

[0078]

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Example 1 except that the structure represented by
After a polymer (ionization energy: 5.4 eV) was produced in the same manner as in Example 1, an organic EL device was prepared in the same manner as in Example 1, and the measurement was conducted in the same manner as in Example 1. Third result
It is shown in the table. Example 8 In Example 1, the following formula was used as the hole transporting unit.

[0080]

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Except that the diamine structure represented by
The polymer (ionization energy 5.4) was obtained in the same manner as in Example 1.
eV), an organic EL device was prepared in the same manner as in Example 1, and the measurement was performed in the same manner as in Example 1. The results are shown in Table 3.

[0082]

[Table 3]

As is clear from Table 3, in the device of the present invention, a high current can be injected at a low voltage. Example 9 Instead of depositing Alq to a thickness of 50 nm in Example 1, TPB having the following structure was deposited to a thickness of 50 nm as an organic hole transport layer, and then Alq was deposited thereon to a thickness of 50 nm.
An organic EL device was produced in the same manner as in Example 1 except that the film was deposited to a thickness of nm. When a voltage of 8 V was applied to this device, a current of 90 mA / cm ² could be injected, and 17
A luminance of 10 cd / m ² and an efficiency of 1.9 cd / A were obtained. In this embodiment, the efficiency is higher than that of the first embodiment. This is probably because the organic hole transport layer prevents the excited state generated by the recombination from disappearing (due to nonradiative transition) by the hole injection transport band. <TPB>

[0084]

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Example 8 An organic EL device was prepared in the same manner as in Example 7, except that TPB was deposited to a thickness of 5 nm instead of depositing TPB to a thickness of 50 nm. An element was manufactured. When a voltage of 8 V was applied to this device, a current of 100 mA / cm ² could be injected and 2500 c
A luminance of d / m ² and an efficiency of 2.5 cd / A were obtained. In this embodiment, the efficiency is higher than that of the first embodiment. This is because LiF is transparent and the band cap is 4e
V or more, which is considered to be due to the fact that the quenching is prevented, the electrons are blocked, and the recombination probability is enhanced.

[0086]

According to the present invention, low voltage, high luminance,
An organic EL element that can achieve a long life and no defects can be easily obtained. The organic EL element of the present invention is suitably used, for example, as a display of information industry equipment.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of an example of an organic EL device of the present invention.

[Explanation of symbols]

 1: anode 2: hole injection transport zone 3: emission zone 4: cathode

Claims (11)

[Claims] 1. An organic electroluminescence device comprising a hole injection / transport zone and a light-emitting band sequentially provided from an anode side between an anode and a cathode, wherein the hole injection / transport zone has three or more aromatic rings. A polymer having a hole transport unit comprising:
An organic electroluminescence device comprising at least a dopant capable of oxidizing the hole transport unit. 2. The organic electroluminescent device according to claim 1, wherein the hole transporting unit is a unit derived from a compound selected from diamine, triarylamine oligomer, thiophene oligomer, arylenevinylene oligomer and styrylamine. 3. The ionization energy of the hole transport unit is:
3. The organic electroluminescent device according to claim 1, which has a voltage of 5.7 eV or less. 4. The organic electroluminescent device according to claim 1, wherein the polymer is a copolymer containing a hole transport unit and a non-conjugated spacer group. 5. The polymer of the formula (I) [Ar ^{1 to} Ar ⁴ independently represent a substituted or unsubstituted arylene group having 6 to 30 carbon atoms. Ar ⁵ and Ar
⁶ independently represents an alkyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. G is a single bond, an alkylene group having 5 to 30 carbon atoms, a cycloalkylene group having 5 to 30 carbon atoms, an arylene group having 6 to 30 carbon atoms, -O-, -S- or (Ar ⁷ is an arylene group having 6 to 30 carbon atoms;
^{8 to} Ar ¹⁰ each represent an aryl group having 6 to 30 carbon atoms, and Ar ^{7 to} Ar ¹⁰ may be substituted with the same substituents as those described above for G. ). P is 0, 1 or 2, q is 0, 1 or 2, and X represents a non-conjugated spacer group. In addition, n shows an average degree of polymerization. 5. The organic electroluminescent device according to claim 4, wherein the organic electroluminescent device is a carbonate copolymer represented by the following formula: 6. The organic electroluminescent device according to claim 1, wherein the polymer is a copolymer containing a hole transport unit and an electron transport unit. 7. The organic electroluminescent device according to claim 1, wherein the polymer has an energy dispersion of 0.2 eV or less. 8. The organic electroluminescent device according to claim 1, wherein the dopant is at least one selected from metal halides, Lewis acids, organic acids, and salts of arylamines with metal halides or Lewis acids. 9. The method according to claim 1, wherein the dopant is of the formula (II) The organic electroluminescent device according to claim 8, which is a compound represented by the following formula: 10. The organic electroluminescent device according to claim 1, wherein the light emitting band comprises a hole transport layer and an organic light emitting layer. 11. The method according to claim 1, wherein the hole injecting / transporting zone has conductivity and has a hole carrier, thereby reducing the size of the energy barrier between the anode and the hole injecting / transporting zone. Organic electroluminescent element.