JP2000100570A - Luminescent device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a device high in luminous efficiency, high in luminance and excellent in color purity by inhabiting a material administering luminescence between a positive electrode and a negative electrode, and containing a metallic complex consisted of a ligand having a 1,2,4-triazole skeleton in a device radiated by electric energy. SOLUTION: Preferably, a device includes a metallic complex consisted of a ligand having a 1,2,4-triazole skeleton shown in the formula (in the formula, R1 to R3 may be the same as or different from one another, are selected from a ring structure formed between hydrogen, an alkyl group and a cycloalkyl group, where at least one of R1 to R3 has any of a hydroxy group, the mercapto group, an unsubstituted or a monosubstituted amino group or an unsubstituted carboxy group). Preferably, the metallic complex is a luminescent material and an electron transport material. The luminescent device is a device that constitutes a display presented by the matrix and/or segment method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an element capable of converting electric energy into light, and relates to a display element, a flat panel display, a backlight, lighting, an interior, a sign, a sign, an electrophotographic device, an optical signal generator, and the like. The present invention relates to a light emitting element that can be used in the field of (1).

[0002]

2. Description of the Related Art In recent years, active research has been conducted on organic thin-film light emitting devices that emit light when electrons injected from a negative electrode and holes injected from a positive electrode recombine in an organic phosphor sandwiched between both electrodes. I have. This element is characterized by thinness, high luminance light emission under a low driving voltage, and multicolor light emission by selecting a fluorescent material.

[0003] It is known from Kodak's C.I. W. Tang et al. (Appl. Phys. Lett. 51 (12)
21, p. 913, 1987). A typical configuration of the organic laminated thin-film light emitting device presented by Kodak Company is a hole transporting diamine compound and a light emitting layer on an ITO glass substrate,
8-Hydroxyquinoline aluminum, which also has an electron transporting property, and Mg: Ag as a negative electrode were sequentially provided, and green light emission of 1000 candela / m 2 was possible at a driving voltage of about 10 V. The current organic laminated thin-film light-emitting device has a different configuration, such as a device provided with an electron transport layer, in addition to the above-described device components, but basically follows the configuration of Kodak. I have.

[0004] The light emitting layer is composed of a host material alone or a host material doped with a guest material. Examples of the host material include metal chelated oxinoid compounds such as tris (8-quinolinolato) aluminum, diarylbutadiene derivatives, stilbene derivatives, benzoxazole derivatives, and benzothiazole derivatives (Japanese Unexamined Patent Publication No.
264,692) and the like.

On the other hand, as dopant materials as guest materials, fluorescent coumarin dyes such as 7-dimethylamino-4-methylcoumarin, dicyanomethylenepyran dye, and the like, which are known to be useful as laser dyes, Dicyanomethylenethiopyran dye, polymethine dye, cyanine dye, oxobenzanthracene dye, xanthene dye, rhodamine dye, fluorescein dye,
Pyrylium dye, carbostyril dye, perylene dye,
Acridine dye, bis (styryl) benzene dye, pyrene dye, oxazine dye, phenylene oxide dye (JP-A-63-264892), perylene, tetracene, pentacene (JP-A-2-261889), quinacridone compounds, quinazoline compounds (JP-A-5-70773) pyrrolopyridine compound, furopyridine compound (JP-A-5-222360),
2,5-thiadiazolopyrene derivatives (JP-A-5-222)
No. 361), perinone derivatives (JP-A-5-2796)
62, a pyrrolopyrrole compound (JP-A-5-32)
No. 0663), squarylium compounds (Japanese Unexamined Patent Publication No.
93257), a biolanthrone compound (Japanese Unexamined Patent Publication No.
-90259), phenazine derivatives (Japanese Unexamined Patent Publication No.
102250), an acridone compound (Japanese Unexamined Patent Publication No.
No. 67873), diazaflavin derivatives (Japanese Unexamined Patent Publication No.
-78058) and the like.

[0006]

However, the luminescent materials (host materials and dopant materials) used in the prior art include those having low luminous efficiency and high power consumption, and those having low durability of the compound and short element life. There were many. In addition, red, green, and blue light emission of three primary colors is required as a full-color display. However, in red and blue light emission, few light emission wavelengths are satisfied, and few light emission peaks have a wide emission peak width and good color purity. In particular, for blue light emission, a material having excellent durability and sufficient luminance and color purity characteristics is required.

An object of the present invention is to solve the problems of the prior art and to provide a light emitting device having high luminous efficiency, high luminance and excellent color purity.

[0008]

According to the present invention, there is provided an element which emits light by electric energy, in which a substance responsible for light emission exists between a positive electrode and a negative electrode, and the element has a 1,2,4-triazole skeleton. A light-emitting element including a metal complex including a ligand.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A positive electrode according to the present invention is made of a conductive metal oxide such as tin oxide, indium oxide, indium tin oxide (ITO), or gold, silver, chromium, if it is transparent to extract light. Metals such as, for example, inorganic conductive substances such as copper iodide and copper sulfide, and conductive polymers such as polythiophene, polypyrrole, and polyaniline are not particularly limited, but it is particularly preferable to use ITO glass or Nesa glass. The resistance of the transparent electrode is not limited as long as a current sufficient for light emission of the element can be supplied, but is preferably low from the viewpoint of power consumption of the element. For example, an ITO substrate having a resistance of 300Ω / □ or less functions as an element electrode, but a substrate having a resistance of about 20Ω / □ or less should be used because a substrate of about 10Ω / □ can be supplied at present. Is particularly desirable. The thickness of the ITO can be arbitrarily selected according to the resistance value.
It is often used between ３００300 nm. Further, as the glass substrate, soda lime glass, non-alkali glass or the like is used, and the thickness only needs to be sufficient to maintain the mechanical strength.
As for the material of the glass, alkali-free glass is preferable because it is better that ions eluted from the glass are small,
Soda lime glass provided with a barrier coat such as SiO ₂ is also commercially available and can be used. The method of forming the ITO film is not particularly limited, such as an electron beam evaporation method, a sputtering method, and a chemical reaction method.

[0010] The negative electrode of the present invention efficiently transfers electrons,
The substance is not particularly limited as long as it can be injected into a substance which controls light emission or a substance adjacent to the substance which controls light emission (for example, an electron transporting layer). Generally, platinum, gold, silver, copper, iron, tin, aluminum, indium, lithium, sodium, potassium, calcium, magnesium and the like can be mentioned. In order to improve the device characteristics by increasing the electron injection efficiency, lithium, sodium, potassium, calcium, magnesium or an alloy containing these low work function metals is effective. However, these low work function metals are generally unstable in the atmosphere, and platinum, gold,
Metals such as silver, copper, iron, tin, aluminum and indium, or alloys using these metals, and silica,
It is preferable to laminate an inorganic substance such as titania and a polymer such as polyvinyl alcohol and vinyl chloride. These electrodes are also manufactured by resistance heating method evaporation, electron beam evaporation method,
There is no particular limitation as long as electrical continuity such as a sputtering method, an ion plating method, and a coating method can be achieved.

In the present invention, the structure of the substance that controls light emission is as follows:
1) a hole transporting material / a light emitting material, 2) a hole transporting material / a light emitting material / an electron transporting material, 3) a light emitting material / an electron transporting material, and 4) a form in which a combination of the above substances is mixed.
Any of these may be used. That is, in addition to the multi-layer structure of 1) to 3), a layer containing a luminescent material alone or a luminescent material and a hole transporting material, or a layer containing a luminescent material, a hole transporting material and an electron transporting material as in 4) is further provided. It may just be provided.

The light-emitting material may be either a host material alone or a combination of a host material and a dopant material. In addition, the dopant material may be included in the entire host material, partially, or may be included. The dopant material may be stacked, dispersed, or the like.

The hole transporting material in the present invention is required to efficiently transport holes from the positive electrode between the electrodes to which an electric field is applied, and has a high hole injection efficiency. Good transport is desirable. For that purpose, it is required that the ionization potential be small, the hole mobility be large, the stability be further improved, and impurities serving as traps be hardly generated during production and use. The substance satisfying such conditions is not particularly limited, but is a biscarbazolyl derivative,
Known triphenylamine derivatives such as TPD, m-MTDATA, α-NPD, pyrazoline derivatives, stilbene compounds, hydrazone compounds, heterocyclic compounds represented by oxadiazole derivatives and phthalocyanine derivatives, polyvinyl carbazole, polysilane and the like Hole transport materials can be used. These hole transport materials may be used alone or may be laminated or mixed with different hole transport materials.

The luminescent material according to the present invention contains a metal complex comprising a ligand having a 1,2,4-triazole skeleton represented by the following general formula (1).

[0015]

Embedded image Here, R1 to R3 may be the same or different, and may be hydrogen, an alkyl group, a cycloalkyl group, an aralkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a hydroxyl group, a mercapto group, an alkoxy group, an alkylthio group, or an aryl ether. Group, arylthioether group,
Aryl group, heterocyclic group, halogen, haloalkane, haloalkene, haloalkyne, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, silyl group, siloxanyl group, And a ring structure formed therebetween. However, at least one of R1 to R3 in the general formula (1) has any of a hydroxyl group, a mercapto group, an unsubstituted or monosubstituted amino group, and an unsubstituted carboxyl group necessary for forming a metal complex.

In the description of these substituents, the alkyl group means a saturated aliphatic hydrocarbon group such as a methyl group, an ethyl group, a propyl group and a butyl group, which may be unsubstituted or substituted. Absent. The cycloalkyl group is, for example, cyclopropyl, cyclohexyl, norbornyl, shows a saturated alicyclic hydrocarbon group such as adamantyl,
This may be unsubstituted or substituted. Also,
The aralkyl group refers to an aromatic hydrocarbon group via an aliphatic hydrocarbon such as a benzyl group and a phenylethyl group, and the aliphatic hydrocarbon and the aromatic hydrocarbon may be unsubstituted or substituted. . The alkenyl group refers to an unsaturated aliphatic hydrocarbon group containing a double bond such as a vinyl group, an allyl group and a butadienyl group, which may be unsubstituted or substituted. Further, the cycloalkenyl group refers to an unsaturated alicyclic hydrocarbon group containing a double bond such as a cyclopentenyl group, a cyclopentadienyl group, and a cyclohexene group, which may be unsubstituted or substituted. . The alkynyl group means an unsaturated aliphatic hydrocarbon group containing a triple bond such as an acetylenyl group, which may be unsubstituted or substituted. The alkoxy group refers to an aliphatic hydrocarbon group via an ether bond such as a methoxy group,
The aliphatic hydrocarbon group may be unsubstituted or substituted. The alkylthio group is obtained by substituting the oxygen atom of the ether bond of the alkoxy group with a sulfur atom.
Further, the aryl ether group refers to an aromatic hydrocarbon group via an ether bond such as a phenoxy group, and the aromatic hydrocarbon group may be unsubstituted or substituted. Further, the arylthioether group is a group in which an oxygen atom of an ether bond of the arylether group is substituted with a sulfur atom. Further, the aryl group is, for example, a phenyl group,
Naphthyl group, biphenyl group, phenanthryl group, terphenyl group, represents an aromatic hydrocarbon group such as a pyrenyl group,
This may be unsubstituted or substituted. Also,
The heterocyclic group refers to a cyclic structure group having an atom other than carbon, such as a furyl group, a thienyl group, an oxazolyl group, a pyridyl group, a quinolyl group, and a carbazolyl group, which may be unsubstituted or substituted. Halogen refers to fluorine, chlorine, bromine and iodine. Haloalkanes, haloalkenes, and haloalkynes are those in which some or all of the aforementioned alkyl, alkenyl, and alkynyl groups, such as trifluoromethyl, have been substituted with the aforementioned halogens, and the rest are unsubstituted. It may be replaced. Aldehyde groups, carbonyl groups, ester groups, carbamoyl groups, and amino groups include those substituted with aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, heterocycles, and the like. The cyclic hydrocarbon, aromatic hydrocarbon and heterocyclic ring may be unsubstituted or substituted. The silyl group indicates a silicon compound group such as a trimethylsilyl group, which may be unsubstituted or substituted. The siloxanyl group refers to a silicon compound group via an ether bond such as a trimethylsiloxanyl group, which may be unsubstituted or substituted. The ring structure formed between adjacent substituents may be unsubstituted or substituted.

The metal forming the metal complex is not particularly restricted but includes, for example, lithium, sodium, potassium, beryllium, calcium, zinc, aluminum and gallium.

In the present invention, 1, 2, 4 of the general formula (1)
A ligand having a triazole skeleton has a coordinating ability,
It has any of a hydroxyl group, a mercapto group, an unsubstituted or monosubstituted amino group, and an unsubstituted carboxyl group. Among them, it is preferable to have a hydroxyl group, and more specifically, a hydroxyl group represented by any of formulas (3) to (5). There is a child.

[0019]

Embedded image

Embedded image

Embedded image Here, R1 to R3 and R7 to R10 may be the same or different, and each may be hydrogen, an alkyl group, a cycloalkyl group, an aralkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a hydroxyl group, a mercapto group, an alkoxy group, or an alkylthio group. Group, aryl ether group, aryl thioether group, aryl group, heterocyclic group, halogen, haloalkane, haloalkene, haloalkyne, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, silyl Group,
It is selected from a siloxanyl group and a ring structure formed between adjacent substituents.

The description of these substituents is the same as described above.

Specific examples of the ligand having the above triazole skeleton include the following structures.

[0022]

Embedded image

Embedded image Further, the light emitting material of the present invention contains a metal complex comprising a ligand having a 1,2,4-triazole skeleton represented by the following general formula (2).

[0023]

Embedded image Here, R4 to R6 may be the same or different, and each represents hydrogen, an alkyl group, a cycloalkyl group, an aralkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a hydroxyl group, a mercapto group, an alkoxy group, an alkylthio group, or an aryl ether. Group, arylthioether group,
Aryl group, heterocyclic group, halogen, haloalkane, haloalkene, haloalkyne, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, silyl group, siloxanyl group, And a ring structure formed therebetween. However, at least one of R5 and R6 in the general formula (2) has any of a hydroxyl group, a mercapto group, an unsubstituted or monosubstituted amino group, and an unsubstituted carboxyl group necessary to form a metal complex.

Further, the ligand having a 1,2,4-triazole skeleton represented by the general formula (2) in the present invention has a coordinating ability, such as a hydroxyl group, a mercapto group, an unsubstituted or monosubstituted amino group, and an unsubstituted carboxyl group. It has any one of the groups, and among them, preferably has a hydroxyl group, and specifically includes a ligand represented by the following general formula (6).

[0025]

Embedded image Here, R4 to R6 and R11 to R14 may be the same or different, and each may be hydrogen, an alkyl group, a cycloalkyl group, an aralkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a hydroxyl group, a mercapto group, an alkoxy group, or an alkylthio group. Group, aryl ether group, aryl thioether group, aryl group, heterocyclic group, halogen, haloalkane, haloalkene, haloalkyne, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, silyl Group,
It is selected from a siloxanyl group and a ring structure formed between adjacent substituents.

The description of these substituents is the same as described above.

Specific examples of the above-mentioned ligand having a triazole skeleton include the following structures.

[0028]

Embedded image

Embedded image A metal complex having a triazole skeleton may be used as a dopant material, but is preferably used as a host material because of its excellent electron transporting ability.

The host material of the light-emitting material is not limited to one kind of a compound having a metal complex having a triazole skeleton, and may be a mixture of a plurality of metal complexes having a triazole skeleton or a known host material. One or more kinds may be used as a mixture with a metal complex having a triazole skeleton.
Examples of the known host material include, but are not particularly limited to, condensed ring derivatives such as anthracene and pyrene, metal chelated oxinoid compounds including tris (8-quinolinolato) aluminum, which have been known as a luminous substance, Bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, coumarin derivatives, oxadiazole derivatives, pyrrolopyridine derivatives, perinone derivatives, cyclopentadiene derivatives, oxadiazole derivatives, thiadiazolopyridine derivatives, and polymers In the system, a polyphenylenevinylene derivative, a polyparaphenylene derivative, a polythiophene derivative and the like can be used.

The dopant material to be added to the light emitting material is not particularly limited, but specifically, conventionally known condensed ring derivatives such as perylene and rubrene, quinacridone derivatives, phenoxazone 660, DCM1,
Perinone and coumarin derivatives can be used as they are, but isobenzofuran derivatives are particularly preferably used.

As the electron transporting material in the present invention,
It is necessary to efficiently transport electrons from the negative electrode between the electrodes to which an electric field is applied, and it is desirable that the electron injection efficiency is high and the injected electrons are transported efficiently. For this purpose, it is required that the material has a high electron affinity, a high electron mobility, a high stability, and a small amount of impurities serving as traps during production and use. Materials satisfying such conditions include quinolinol derivative metal complexes represented by 8-hydroxyquinoline aluminum, tropolone metal complexes, flavonol metal complexes, perylene derivatives, perinone derivatives, naphthalene,
There are coumarin derivatives, oxadiazole derivatives, aldazine derivatives, bisstyryl derivatives, pyrazine derivatives, phenanthroline derivatives, and the like, but are not particularly limited. The metal complex having a triazole skeleton according to the present invention also has excellent electron transporting ability, and thus can be suitably used as an electron transporting material. These electron transporting materials may be used alone or may be laminated or mixed with different electron transporting materials.

The above materials used for the hole transporting layer, the light emitting layer and the electron transporting layer can be used alone to form each layer. Examples of the polymer binder include polyvinyl chloride, polycarbonate, polystyrene, and the like. Poly (N-vinyl carbazo-
), Polymethyl methacrylate, polybutyl methacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, hydrocarbon resin, ketone resin, phenoxy resin, polyamide, ethyl cellulose
Curing of solvent-soluble resins such as water, vinyl acetate, ABS resin and polyurethane resin, phenol resin, xylene resin, petroleum resin, urea resin, melamine resin, unsaturated polyester resin, alkyd resin, epoxy resin, silicone resin, etc. It is also possible to use it by dispersing it in a conductive resin or the like.

The method for forming the substance which controls light emission in the present invention is not particularly limited, such as resistance heating evaporation, electron beam evaporation, sputtering, molecular lamination, and coating. Beam evaporation is preferred in terms of properties. The thickness of the layer cannot be limited because it depends on the resistance value of the substance that controls light emission.
00 nm.

The electric energy in the present invention mainly refers to a direct current, but it is also possible to use a pulse current or an alternating current. The current value and voltage value are not particularly limited,
In consideration of the power consumption and life of the device, it is necessary to obtain the maximum brightness with the lowest possible energy.

It is preferable that the light emitting device of the present invention constitutes a display for displaying by a matrix or segment system or a combination of both.

The matrix according to the present invention refers to a matrix in which pixels for display are arranged in a lattice, and displays a character or an image by a set of pixels. The shape and size of the pixel depend on the application. For example, for the display of images and characters on personal computers, monitors, televisions, and the like, generally square pixels with a side of 300 μm or less are used, and in the case of a large display such as a display panel, pixels with a side on the order of mm are used. Become. In the case of monochrome display, pixels of the same color may be arranged, but in the case of color display, red, green and blue pixels are displayed side by side. In this case, there are typically a delta type and a stripe type. Note that the light-emitting element of the present invention can emit red, green, and blue light, so that multi-color or full-color display can be performed by using the display method. The matrix may be driven by either a line-sequential driving method or an active matrix. The line-sequential driving has the advantage of a simpler structure, but the active matrix is sometimes superior in consideration of the operating characteristics. Therefore, it is necessary to use this depending on the application.

In the segment type according to the present invention, a pattern is formed so as to display predetermined information, and a predetermined area emits light. For example, there are a time display and a temperature display on a digital clock or a thermometer, an operation state display of an audio device, an electromagnetic cooker, or the like, and a panel display of an automobile. The matrix display and the segment display may coexist in the same panel.

The light emitting device of the present invention is also preferably used as a backlight. The backlight in the present invention,
It is mainly used for improving the visibility of a display device that does not emit light, and is used for a liquid crystal display device, a clock, an audio device, an automobile panel, a display panel, a sign, and the like. In particular, as for the backlight for liquid crystal display devices, particularly for personal computer applications where thinning is an issue, the present invention is considered to be difficult because the conventional type is made of a fluorescent lamp or a light guide plate, and it is difficult to make it thin. Is characterized by its thinness and light weight.

[0039]

The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

Example 1 A glass substrate (15 Ω / □, electron beam vapor-deposited product, manufactured by Asahi Glass Co., Ltd.) on which an ITO transparent conductive film was deposited to a thickness of 150 nm was 30
The wafer was cut into a size of 40 mm and etched. The obtained substrate was subjected to ultrasonic cleaning with acetone and semicocrine 56 for 15 minutes each, and then with ultrapure water. Subsequently, the substrate was subjected to ultrasonic cleaning with isopropyl alcohol for 15 minutes, immersed in hot methanol for 15 minutes, and dried. This substrate was subjected to UV-ozone treatment for 1 hour immediately before producing the element, placed in a vacuum evaporation apparatus, and evacuated until the degree of vacuum in the apparatus became 5 × 10 ⁻⁵ Pa or less. First, 4,4′-bis (N- (m-tolyl) -N-phenylamino) biphenyl was deposited as a hole transporting material to a thickness of 100 nm by a resistance heating method. Next, a zinc complex of 2-phenyl-3- (2-hydroxyphenyl) -5-phenyl-1,2,4-triazole was laminated to a thickness of 100 nm as a host material. Next, 0.5 nm of lithium and 200 nm of aluminum were vapor-deposited to form a cathode, and a 5 × 5 mm square element was produced. The film thickness referred to here is a value displayed on a crystal oscillation type film thickness monitor corrected by a value measured by a surface roughness meter. Good blue light emission was obtained from this light emitting device.

Comparative Example 1 Bis (2-methylquinolinolate) as a host material
Except for using (2-pyridinolate) aluminum (III), a light-emitting device manufactured in exactly the same manner as in Example 1 could only emit blue-green light.

Example 2 Copper phthalocyanine was used as a hole transport material at 20 nm,
Good blue light emission was obtained from the light-emitting device manufactured in exactly the same manner as in Example 1 except that 100 nm of 3'bis (ethylcarbazole) was used.

Example 3 A zinc complex of 2-phenyl-3- (2-hydroxyphenyl) -5-phenyl-1,2,4-triazole was used as a host material, and 1,3-diphenylisobenzofuran was used as a dopant material. From the light emitting device manufactured in exactly the same manner as in Example 1 except that the dopant was co-deposited to a thickness of 30 nm so as to be 1 wt%, and then the host material alone was laminated to a thickness of 70 nm, Blue light emission was obtained.

Example 4 3- (2-hydroxyphenyl) -4 as a host material
Good blue light emission was obtained from the light-emitting device manufactured in the same manner as in Example 1 except that a zinc complex of -phenyl-5-phenyl-1,2,4-triazole was used.

Example 5 Copper phthalocyanine was used as a hole transport material at 20 nm,
Good blue light emission was obtained from the light emitting device manufactured in the same manner as in Example 4 except that 100 nm of 3'bis (ethylcarbazole) was used.

Example 6 3- (2-hydroxyphenyl) -4 as a host material
A zinc complex of -phenyl-5-phenyl-1,2,4-triazole is co-evaporated to a thickness of 30 nm using 1,3-diphenylisobenzofuran as a dopant material so that the dopant is 1 wt%; Next, good blue light emission was obtained from the light-emitting element manufactured in exactly the same manner as in Example 4 except that the host material alone was laminated to a thickness of 70 nm.

[0047]

The present invention can provide a light emitting device having high luminous efficiency, high luminance and excellent color purity. It is particularly effective for blue light emission.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3K007 AB02 AB03 AB04 AB17 BA06 CA01 CB01 DA00 DB03 EB00 FA01

Claims (9)

[Claims] An element which emits light by electric energy, in which a substance responsible for light emission exists between a positive electrode and a negative electrode, wherein the element comprises a metal complex comprising a ligand having a 1,2,4-triazole skeleton. A light-emitting element comprising: 2. An element which emits light by electric energy, in which a substance responsible for light emission exists between a positive electrode and a negative electrode, wherein the element is a 1,2,4-triazole skeleton represented by the following general formula (1). The light emitting device according to claim 1, comprising a metal complex comprising a ligand having the following formula: Embedded image (Where R1 to R3 may be the same or different and each represents a hydrogen, an alkyl group, a cycloalkyl group, an aralkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a hydroxyl group, a mercapto group, an alkoxy group, an alkylthio group, an aryl Ether group, arylthioether group,
Aryl group, heterocyclic group, halogen, haloalkane, haloalkene, haloalkyne, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, silyl group, siloxanyl group, And a ring structure formed therebetween. However, at least one of R1 to R3 has any of a hydroxyl group, a mercapto group, an unsubstituted or monosubstituted amino group, and an unsubstituted carboxyl group necessary to form a metal complex. ) 3. An element which emits light by electric energy, wherein a substance responsible for light emission exists between a positive electrode and a negative electrode, wherein the element is a 1,2,4-triazole skeleton represented by the following general formula (2). The light emitting device according to claim 1, comprising a metal complex comprising a ligand having the following formula: Embedded image (Where R4 to R6 may be the same or different and each represents a hydrogen, an alkyl group, a cycloalkyl group, an aralkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a hydroxyl group, a mercapto group, an alkoxy group, an alkylthio group, an aryl Ether group, arylthioether group,
Aryl group, heterocyclic group, halogen, haloalkane, haloalkene, haloalkyne, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, silyl group, siloxanyl group, And a ring structure formed therebetween. However, at least one of R5 and R6 has any of a hydroxyl group, a mercapto group, an unsubstituted or monosubstituted amino group, and an unsubstituted carboxyl group necessary to form a metal complex. ) 4. The light emitting device according to claim 2, wherein the ligand having a triazole skeleton represented by the general formula (1) is represented by any of the following general formulas (3) to (5). . Embedded image Embedded image Embedded image (Where R1 to R3 and R7 to R10 may be the same or different, and each may be hydrogen, an alkyl group, a cycloalkyl group, an aralkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a hydroxyl group, a mercapto group, an alkoxy group, Alkylthio group, arylether group, arylthioether group, aryl group, heterocyclic group, halogen, haloalkane, haloalkene, haloalkyne, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, Silyl group,
It is selected from a siloxanyl group and a ring structure formed between adjacent substituents. ) 5. The light emitting device according to claim 3, wherein the ligand having a triazole skeleton represented by the general formula (2) is represented by the following general formula (6). Embedded image (Where R4 to R6 and R11 to R14 may be the same or different, respectively, and include hydrogen, an alkyl group, a cycloalkyl group, an aralkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a hydroxyl group, a mercapto group, an alkoxy group, Alkylthio group, aryl ether group, arylthio ether group, aryl group, heterocyclic group, halogen, haloalkane, haloalkene, haloalkyne, cyano group,
It is selected from an aldehyde group, a carbonyl group, a carboxyl group, an ester group, a carbamoyl group, an amino group, a nitro group, a silyl group, a siloxanyl group, and a ring structure formed between adjacent substituents. ) 6. The light emitting device according to claim 1, wherein said metal complex is a light emitting material. 7. The light emitting device according to claim 1, wherein said metal complex is an electron transporting material. 8. The light emitting device according to claim 1, wherein the light emitting device constitutes a display for displaying in a matrix and / or segment system. 9. The light emitting device according to claim 1, wherein the light emitting device is a backlight.