WO2006001239A1

WO2006001239A1 - White light-emitting compound, white light-emitting polymer compound, method for producing those, and light-emitting device

Info

Publication number: WO2006001239A1
Application number: PCT/JP2005/011232
Authority: WO
Inventors: Tadao Nakaya; Atsushi Ikeda; Mitukura Sato
Original assignee: Hirose Engineering Co., Ltd.
Priority date: 2004-06-28
Filing date: 2005-06-20
Publication date: 2006-01-05
Also published as: TW200613511A

Abstract

Disclosed is a white light-emitting compound which is a single compound capable of emitting white light and can be used, for example, for an organic EL device. Also disclosed are a method for producing such a white light-emitting compound and a light-emitting device using such a white light-emitting compound. Specifically disclosed is a white light-emitting compound which is characterized by having a structure expressed as below.

Description

White light emitting compound, white light emitting polymer compound, production method thereof and light emitting device

Technical field

The present invention relates to a white light-emitting compound, a white light-emitting polymer compound, a method for producing the same, and a light-emitting device. More specifically, the present invention relates to a white light-emitting compound that is a novel substance capable of emitting white light while being a single compound. The present invention also relates to a white light emitting polymer compound obtained by polymerizing the white light emitting compound, the white light emitting compound, and a light emitting device containing at least one of the white light emitting polymer compound.

Background art

[0002] Conventionally, organic EL devices have been developed mainly for devices that emit light of R, G, and B, respectively, and white light emitting devices. White light emission was achieved by mixing a plurality of light emission colors to achieve white light emission (see Patent Document 1).

However, there are few known compounds that emit white fluorescence with a single compound.

[0004] Patent Document 1: Japanese Patent Laid-Open No. 63-19796

[0005] A white light-emitting element capable of emitting white light by mixing a red light-emitting compound, a green light-emitting compound, and a blue light-emitting compound is conceivable. In other words, red light emission compound, green light emission compound and blue light emission compound existing in one light emitting element emit red light, green light emission and blue light emission, and the three primary colors of R, G, and B are mixed, resulting in white light emission. To achieve this with its light-emitting elements. However, since the red light emitting compound, the green light emitting compound, and the blue light emitting compound have mutually different molecular structures, the light emission lifetimes of the respective light emitting compounds are different. Then, the light emitting element having a mechanism for emitting three kinds of light emitting compounds has a problem that the color of light emission changes from white to non-white over time.

Disclosure of the invention

Problems to be solved by the invention

[0006] An object of the present invention is to provide a white light-emitting compound that can emit white light, for example, a single compound that can be used in an organic EL device, a method for producing the same, and a white light-emitting polymer capable of white light It is in providing the compound, the manufacturing method of a white light emitting polymer compound, and a light emitting element. Another object of the present invention is to provide an organic compound capable of emitting white light that can be used for various white light emitters including an organic EL element. As a result of diligent research to achieve this goal, we have succeeded in synthesizing a single fluorescent compound capable of emitting high-purity white light and invented a high-life EL device.

Means for solving the problem

[0007] As means for solving the above problems,

Claim 1 is a white light-emitting compound characterized by having a structure represented by the following formula (1):

[0008] [Chemical 1] γ ······· J ^

(However, in the above formula (1), two Rs represent a substituent represented by the following formula (11) or (12), and two Ars represent an aromatic group. In the formula, two R ^{1 s} may be the same or different from each other, and two Ars may be the same or different from each other.

[0010] [Chemical 2]

(However, in the above formula (1-1), R ² may be substituted with a hydrogen atom or a halogen atom having 1 to 5 carbon atoms, and represents an alkyl group.)

[0012] [Chemical 3]

\ I)

[0013] (provided that in the formula (1 2), the two R ^3, a hydrogen atom or a § alkyl group having 1 to 20 carbon atoms. In the formula, the two R ^3, together It can be the same or different.)

Claim 2 is a white light emitting polymer compound having a monomer unit represented by the formula (11A),

[0014] [Chemical 4] -(CH-CH ₂ )-

[0015] Claim 3 is according to reaction formula 1 below:

[0016] [Chemical 5]

Anti It,; ill

HO COOR ⁵

2 R ^! — H ₂

', No ...

R ^J OOC OH

(a) (b)

]

(c)

[0017] 1,4 dihydroxy-1,2,5 dialkylcarboxy-1,4-cyclohexagen (a)

(However, R ⁵ in the compound (a), an alkyl group.) And § - phosphorus derivative (b) (provided that R ¹ in the compound (b) is the same as R ¹ indicated in claim 1 )) In a solvent to give 1,4-dihydroxy 2,5 dialkylcarboxy 1,4-si Compound (c) was synthesized by dehydrating clohexagen ( _a ) and arrin derivative (b),

Then, according to the following reaction formula 2,

[0018] [Chemical 6]

Reaction ≥ m ί * ¹ ^ * ^ * ^ R ¹ — MH COOR5

R ⁵ OOC MH RR ⁵ 00C NH― R

[0019] The compound (c) is dehydrogenated to synthesize an aromatic compound (d),

Then according to Scheme 3

[0020] [Chemical 7]

[0021] The aromatic compound (d) is hydrolyzed to synthesize a dicarboxylic acid compound (e). According to the following reaction formula 4,

[0022] [Chemical 8] Reaction formula 4

[0023] Dicarboxylic acid compound (e) is derived into acid halide compound (f),

According to the following reaction formula 5,

[0024] [Chemical 9]

£ ¾J mind: ¾5 1— NH

Ar-CONHNH2

XOC NH 1 R ff)

I I Π

0 0

(g)

[0025] Acid halide (f) and hydrazide represented by Ar—CONHNH (where Ar is

2

Same as R ¹ shown in Claim 1. ) To synthesize compound (g),

Furthermore, according to the following reaction formula 6,

[0026] [Chemical 10] I7 ~ r——-

Ar

0

[0027] The compound (g) is subjected to a cyclization reaction to be derivatized into an oxadiazole ring-containing compound (h). According to the following reaction formula 7,

[0028] [Chemical 11]

Ar

It is characterized by dehalogenation and dehydrochlorination by reacting an oxaziazole ring-containing compound (h) with a 3-chloromethyl-9- (2-chloroethyl) force rubazole represented by 0 The white light-emitting polymer according to claim 1, wherein the white light-emitting compound according to claim 1 is polymerized with the white light-emitting compound represented by the formula (1). A method for producing a compound, Claim 5 has a light-emitting layer containing the white light-emitting compound according to claim 1 or the white light-emitting polymer compound according to claim 2 between a pair of electrodes. It is an element.

The invention's effect

The white light-emitting compound according to the present invention has an oxadiazole ring having an aryl group (one Ar) and a substituent (R ¹ ). The oxadiazole ring having an aryl group exhibits electron withdrawing properties, and the substituent (R ¹ ) exhibits electron donating properties. Therefore, the compound having the structure represented by the formula (1) is considered to cause uneven distribution of electrons in the molecule. In addition, it is assumed that the portion with high pi electron density emits red light, and the portion with low pi electron density emits blue light. When white light is observed by simultaneous emission of this red light and blue light, Guessed. Therefore, it appears to humans that the white light-emitting compound according to the present invention emits white light.

[0031] This white light-emitting compound emits white light even though it is a single compound. Therefore, in the light emitting element containing this white light emitting compound in the light emitting layer, the color of light emitted does not change to white color or other colors over time. Therefore, according to the present invention, it is possible to provide a light emitting element having a long white light emission lifetime.

In the white light-emitting compound according to the present invention, a nitrogen atom in the force rubazole skeleton is substituted —CH═CH has polymerizability. Therefore, the white light-emitting compound according to the present invention

2

Becomes a polymer by polymerization. The white light-emitting polymer compound according to the present invention, which is a polymer compound, can be formed into a film by a casting method, a melt casting method, or the like. Since the white light-emitting polymer compound according to the present invention can be easily formed into a film, a light-emitting element capable of emitting white light can be easily produced using this.

Brief Description of Drawings

FIG. 1 is an explanatory view showing a light emitting element as an example according to the present invention.

FIG. 2 is an explanatory view showing a light emitting device as another example according to the present invention.

FIG. 3 is an explanatory view showing a light emitting device as another example according to the present invention.

FIG. 4 is an explanatory view showing a light emitting device as still another example according to the present invention. FIG. 5 is an NMR vector chart of the compound (cl) obtained in the example of the present invention.

FIG. 6 is an NMR vector chart of the compound (dl) obtained in the example of the present invention.

FIG. 7 is an NMR spectrum chart of the compound (el) obtained in the example of the present invention.

FIG. 8 is an IR spectrum chart of the compound (el) obtained in the example of the present invention.

FIG. 9 is an NMR spectrum chart of the compound (f 1) obtained in the example of the present invention.

FIG. 10 is an IR ^ vector chart of the compound (fl) obtained in the example of the present invention.

FIG. 11 is an NMR vector chart of the compound (gl) obtained in the example of the present invention.

FIG. 12 is an IR spectrum chart of the compound (gl) obtained in the example of the present invention.

FIG. 13 is an NMR vector chart of the compound (j 1) obtained in the example of the present invention.

FIG. 14 is an NMR vector chart of compound (1B) obtained in the example of the present invention.

[FIG. 15] FIG. 15 is an IR vector chart of the compound (1B) obtained in the example of the present invention.

FIG. 16 is an NMR spectrum chart of the compound (1C) obtained in the example of the present invention.

FIG. 17 is a fluorescence spectrum chart of the compound (1C) obtained in the example of the present invention.

Explanation of symbols

A, B, C White light emitting element 1 Board

2 Transparent electrode

3 Light emitting layer

4 Electrode layer

BEST MODE FOR CARRYING OUT THE INVENTION

The white light-emitting compound according to the present invention is characterized by having a structure represented by the following formula (1).

[0036] [Chemical 12]

GH2

R ― N

N

Ar G

o

[0037] The white light-emitting compound represented by the formula (1) has a benzene ring at the center of the skeleton. Two oxadiazole rings and two imino groups (one NH—) are bonded to this benzene ring. A force rubazole skeleton is bonded to one imino group via a methylene group. Thus, this white light emitting compound has a unique structure.

[0038] Ar in the above formula (1) is an aromatic group such as a furl group, a tolyl group, a xylyl group, a mesityl group, a thamol group, a biphthyl group, a naphthyl group, an anthryl group, and a antryl group. In particular, a phenyl group, a naphthyl group, or an anthryl group is preferable. Formula (1) The two Ars in are the same or different from each other!

[0039] Formula two R ¹ in (1) is a hydrogen atom or the following formula (1 1) or (1 2) shown by substituents. The two R ^{1 s} may be the same or different from each other. However, in the preferred white light emitting compound, the two R ^{1 s} are the same.

[0040] [Chemical 13]

[0041] In the substituent represented by the formula (11), a hydrogen atom bonded to the nitrogen atom at the 9-position is substituted with the substituent R ^{2 using} force rubazole as a basic skeleton, and further, the hydrogen atom at the 3-position It is a group formed by elimination. R ² represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms which may be substituted with a halogen atom. Examples of the alkyl group having 1 to 20 carbon atoms include ethyl group, methyl group, n-propyl group, isopropyl, n-butyl group, isobutyl group, tert butyl group, n-pentyl group, isopentyl group, tert pentyl group, etc. Can be mentioned. When R ^{2 is} an alkyl group, the greater the carbon number, the better the solubility in the solvent. The substituent represented by the formula (11) is electron donating.

[0042] Among the substituents represented by the formula (11), the substituent represented by the formula (11B) is preferable.

[0043] [Chemical 14]

The substituents represented by formula (12) are shown below.

[Chemical 15]

3 r

[0046] The substituent represented by the formula (12) is a group obtained by substituting the hydrogen atom at the 9-position with R ³ and further eliminating the hydrogen atom at the 3-position with fluorene as a basic skeleton. R ³ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. The alkyl group having 1 to 20 carbon atoms is the same as described above. Two R ^{3 s} may be the same or different, but in the preferred white light-emitting compound represented by the formula (1), the two R ^{3 s} in the formula (1-2) are the same. The substituent represented by the formula (1-2) is electron donating.

[0047] In the white light-emitting compound according to the present invention, two oxaziazole rings are electron-withdrawing groups, NH—R ¹ and N (—R ¹ ) —CH— are electron-donating groups, and a benzene ring Around

2

As a result, it is considered that the energy gap between the excited state and the ground state, which cause light emission, is suitable for white light emission. . In other words, in the white light emitting compound, electrons are unevenly distributed in the molecule, and there are a portion having a high electron density and a portion having a low electron density. When a white light emitting compound having such a specific structure is externally supplied with electrical energy or electromagnetic wave energy, the electron density is high, red light is emitted from the part, and blue light is emitted from the part where the electron density is low. It is estimated that When red light and blue light are mixed, it appears to humans as white light.

[0048] The white light-emitting compound represented by the formula (1) can be produced according to the following reaction formulas 1 to 7. Reaction formulas 1 to 7 shown below are ideal reactions for explaining the route that leads to the white light-emitting compound according to the present invention. In this case, side reactions and competitive reactions proceed.

[0049] First, according to Reaction Formula 1, 1,4-dihydroxy-2,5-dialkylcarboxy-1,4-cyclohexagen (a) and a-line derivative (b) are heated in a solvent. 1,4-dihydroxy-2,5-dianolequinolecanoxyl 1,4-cyclohexagen (a) is dehydrated from the hydroxyl group and the hydrogen atom on the nitrogen atom of the aniline derivative to give the hexagen compound (c). Synthesized.

[0050] [Chemical 16]

(a) (b)

¹

[0051] Here, R ⁵ of 1,4-dihydroxy-2,5-dialkylcarboxy-1,4-cyclohexagen (a) in the above reaction formula 1 represents an alkyl group such as a methyl group, and R ¹ of the derivative (b) is the same as R ¹ described for the white light-emitting compound represented by the formula (1).

[0052] Examples of the solvent include nonpolar solvents such as benzene or methanol, ethanol, acetic acid, phthalic acid, phthalic anhydride, glacial acetic acid, orthodichlorobenzene, metadichlorobenzene, dioxane, pyridine, N, N dimethylformamide. Examples thereof include polar solvents such as (DMF) and tetrahydrofuran (THF). These solvents may be used alone or as a mixture of two or more.

[0053] The reaction temperature is preferably 80 to 130 ° C, particularly 90 to 110 ° C. preferable.

[0054] The heating time is preferably 5 to 7 hours, particularly preferably 5 to 6 hours.

[0055] Next, the aromatic compound (d) can be synthesized by dehydrogenating the hexadene compound (c) according to the reaction formula 2. The dehydrogenation reaction is usually performed in a solvent. A dehydrogenation catalyst can be used for the dehydration reaction. Aromatic compounds are also terephthalic acid ester compounds.

[0056] [Chemical 17]

(c) (d)

[0057] As the dehydrogenation catalyst, acid catalysts such as sulfuric acid, nitric acid and hydrochloric acid, metal catalysts such as chromium, iron, platinum, palladium silver and copper, acid aluminum and acid magnesium, etc. Examples thereof include acid oxides.

[0058] Examples of the solvent include nonpolar solvents such as benzene or methanol, ethanol, acetic acid, phthalic acid, phthalic anhydride, glacial acetic acid, orthodichlorobenzene, metadichlorobenzene, dioxane, pyridine, N, N-dimethyl. Examples include polar solvents such as formamide (DMF) and tetrahydrofuran (THF). These may be used alone or in combination of two or more.

[0059] The heating temperature is preferably 130 to 170 ° C, and particularly preferably 140 to 160 ° C.

[0060] The heating time is preferably 3 to 5 hours, and particularly preferably 3 to 4 hours.

[0061] According to Reaction Formula 3, the obtained aromatic compound (d) is hydrolyzed to obtain an alkyl. The dicarboxylic acid compound (e) is synthesized by using the ruester (—COOR ⁵ ) as a free carboxylic acid. This hydrolysis reaction can be performed by heating in a solvent.

[0062] [Chemical 18]

Anti-it, expression

[0063] Examples of the solvent include nonpolar solvents such as benzene or methanol, ethanol, acetic acid, phthalic acid, phthalic anhydride, glacial acetic acid, orthodichlorobenzene, metadichlorobenzene, dioxane, pyridine, N, N-dimethyl. Examples include polar solvents such as formamide (DMF), N, N-dimethylacetamide (DMAC), and tetrahydrofuran (THF). These may be used alone or in combination of two or more.

[0064] The heating temperature is preferably 80 to 200 ° C, and particularly preferably 100 to 180 ° C.

[0065] The heating time is preferably 0.5 to 4 hours, and more preferably 1.5 to 2.5 hours.

[0066] In addition, in this hydrolysis reaction, only by heating, the reaction is accelerated by the force at which the hydrolysis reaction proceeds. Therefore, an acid such as hydrochloric acid and sulfuric acid, or sodium hydroxide and Use alkali such as potassium hydroxide.

[0067] Next, in accordance with the reaction formula 4, the dicarboxylic acid compound (e) is derived into the acid neurogenic compound (f). This reaction proceeds easily by heating the dicarboxylic acid compound (e) in a solvent.

[0068] [Chemical 19] Reaction formula 4

[0069] Examples of the halogenating agent include chlorinating agents such as chlorothionyl and chlorophosphoryl, and brominating agents such as thionyl bromide.

[0070] Examples of the solvent include nonpolar solvents such as benzene or methanol, ethanol, acetic acid, phthalic acid, phthalic anhydride, glacial acetic acid, orthodichlorobenzene, metadichlorobenzene, dioxane, pyridine, N, N-dimethyl. Examples thereof include polar solvents such as formamide (DMF) and tetrahydrofuran (THF), and these may be used alone or in combination of two or more.

[0071] The heating temperature is preferably 40 to 100 ° C, more preferably 40 to 70 ° C.

[0072] The heating time is preferably 1 to 20 hours, and particularly preferably 1 to 3.5 hours.

[0073] Examples of the halogen atom represented by X in the acid halide (f) include a chlorine atom, a fluorine atom, and a bromine atom. In many cases, X is a chlorine atom.

[0074] Then, according to Reaction Scheme 5, the acid halide (f) and hydrazide (Ar—CONHNH 3)

Compound (g) can be synthesized by heating 2 in a solvent.

[0075] [Chemical 20] Reaction formula 5

R ¹ — NH COX

Ar-CONHNH2

xoc ,, NH― R ¹

Cf)

! ! I!

0 0

(g)

[0076] Examples of the solvent include nonpolar solvents such as benzene or methanol, ethanol, acetic acid, phthalic acid, phthalic anhydride, glacial acetic acid, orthodichlorobenzene, metadichlorobenzene, dioxane, pyridine, N, N-dimethyl. Examples thereof include polar solvents such as formamide (DMF) and tetrahydrofuran (THF), and these may be used alone or in combination of two or more.

[0077] The heating temperature is preferably 40 to 80 ° C, particularly 50 to 75 ° C.

[0078] The heating time is preferably 1 to 5 hours, and particularly preferably 1 to 4 hours.

[0079] The obtained compound (g) can be subjected to a ring-closing reaction by heating in a solvent according to Reaction Scheme 6 to obtain an oxaziazole ring-containing compound (h).

[0080] [Chemical 21] I7 ~ r——-

0

Ch)

[0081] Examples of the solvent may include polar solvents such as phosphoryl chloride, phosphoryl bromide, orthodichlorobenzene, dioxane, pyridine, N, N dimethylformamide (DMF), and tetrahydrofuran (THF). These may be used alone or as a mixture of two or more.

[0082] The heating temperature is preferably 100 to 140 ° C, and particularly preferably 90 to 120 ° C.

[0083] The heating time is preferably 6 to 24 hours, particularly 10 to 17 hours.

[0084] The obtained oxaziazole ring-containing compound (h) is subjected to a substitution reaction by heating in a solvent together with an organic halogen compound in accordance with the reaction formula 7, and then reduced according to the present invention. A white light-emitting compound (1) can be obtained.

(h) CH HgC l

I

R GH ₂

R ^! -—— N

C H = C H 2

N

CH2

In this reaction formula 7, it is still necessary to examine in detail whether the force that compound (j) produces and force compound (1) produces. In fact, compound (h) and compound (i) Prior to the reaction with the compound, the 2-chlorooctyl group in the force rubazole (i) undergoes a desalting hydrogen reaction, or the reaction between the compound (h) and the compound (i) undergoes the dehydrochlorination reaction. There is a possibility of progress. In the above reaction formula 7, the product (1) is obtained from the compound (h) and the compound (i) as raw materials. It should be understood that it only describes the reaction to be synthesized.

[0086] Examples of the solvent include polar solvents such as phosphoryl chloride, phosphoryl bromide, orthodichlorobenzene, dioxane, pyridine, N, N-dimethylformamide (DMF), and tetrahydrofuran (THF). These may be used alone or in combination of two or more.

[0087] The heating temperature is preferably 100 to 180 ° C, and particularly preferably 130 to 170 ° C.

[0088] The heating time is preferably 6 to 24 hours, and particularly preferably 15 to 20 hours.

[0089] After completion of the reaction, the white light-emitting compound (1) can be obtained by purification and separation according to a conventional method.

[0090] The white light-emitting compound according to the present invention can be easily produced simply by heating. Such a simple method for producing a white light-emitting compound is an industrial production method.

[0091] The polymerizable white light-emitting compound represented by the formula (1) is synthesized into the white light-emitting polymer compound according to the present invention by, for example, radical polymerization or ionic polymerization by a normal polymerization operation.

[0092] The polymerization reaction proceeds even in the case of! Or deviation such as Balta polymerization and solution polymerization. In addition, a polymerization initiator may be used for the polymerization reaction, and the polymerization can be initiated by irradiation with electromagnetic wave energy such as ultraviolet rays.

[0093] The molecular weight of the obtained white light-emitting polymer compound is usually 10,000 to 50,000, and a film can be formed. The white light-emitting polymer compound in the form of a film can be used as a light-emitting layer in a light-emitting element by using the film or layer formed with the white light-emitting polymer compound as described below. Therefore, when a white light-emitting polymer compound is used, a light-emitting element can be manufactured easily and at a low cost.

Next, the white light emitting device according to the present invention will be described.

[0095] The white light-emitting compound according to the present invention exhibits visible light emission over a range of 400 to 650 nm as a whole by applying electromagnetic wave energy, and can be used for an organic EL device capable of white light emission. FIG. 1 is an explanatory diagram showing a cross-sectional structure of a white light-emitting element that is also a single-layer organic EL element. As shown in FIG. 1, the white light emitting element A is formed by laminating a light emitting layer 3 containing a light emitting material and an electrode layer 4 in this order on a substrate 1 on which a transparent electrode 2 is formed.

The white light emitting element A shown in FIG. 1 emits white light when a current is passed through the transparent electrode 2 and the electrode layer 4. For light emission, when an electric field is applied between the transparent electrode 2 and the electrode layer 4, electrons on the electrode layer 4 side are injected, holes are injected from the transparent electrode 2, and electrons are further injected into the light emitting layer 3. It is a phenomenon in which energy is released as light when recombining with holes and the energy level returns to the conduction band valence band.

[0098] Moreover, since the white light emitting element A has a white light emitting compound having a specific chemical structure in the light emitting layer, the light emitting life is long. Therefore, the white light emitting element A can be used as a light source having a long lifetime.

[0099] Further, the white light emitting element A is a tubular light emitting body in which a substrate 1 formed in a cylindrical shape and a transparent electrode 2, a light emitting layer 3 and an electrode layer 4 are laminated in this order on the inner surface side of the substrate 1. It can be.

[0100] As the substrate 1, a known substrate can be employed as long as the transparent electrode 2 can be formed on the surface thereof. Examples of the substrate 1 include a glass substrate, a plastic sheet, a ceramic, and a metal plate obtained by processing the surface into an insulating property such as forming an insulating coating layer on the surface. When the substrate 1 is opaque, the white light emitting element is a single-sided illumination device that can irradiate white light on the side opposite to the substrate 1. Further, when the substrate 1 is transparent, it is a double-sided illumination device that can emit white light from the substrate 1 side of the white light emitting element and the surface on the opposite side.

[0101] The transparent electrode 2 is made of various materials as long as it has a large work function and is transparent and can act as an anode by applying a voltage to inject holes into the light emitting layer 3. can do. Specifically, the transparent electrode 2 is made of ITO, InO, SnO, ZnO, Cd

It can be formed of an inorganic transparent conductive material such as 2 3 2o and the like and compounds thereof, and a conductive high molecular material such as polyaniline.

[0102] This transparent electrode 2 is formed on the substrate 1 by chemical vapor deposition, spray pyrolysis, vacuum evaporation, electron beam evaporation, sputtering, ion beam sputtering, ion It can be formed by an etching method, an ion-assisted vapor deposition method, or other methods.

[0103] When the substrate is formed of an opaque member, the electrode formed on the substrate does not have to be a transparent electrode.

[0104] The light emitting layer 3 is a layer containing a white light emitting compound represented by the formula (1) in the present invention. The light emitting layer 3 can be formed as a polymer film in which the white light emitting compound in the present invention is dispersed in a polymer, and the white light emitting compound in the present invention is deposited on the transparent electrode 2. It can be formed as a deposited film.

[0105] Examples of the polymer in the polymer film include polybulucarbazole, poly (3-alkylentiophene), polyimide containing allylamine, polyfluorein, polyphenylene-butylene, poly-a-methylstyrene, biphenyl. -Lucarbazole Z α-methylstyrene copolymer and the like. Among these, polyburecarbazole is preferable.

[0106] The content of the white light-emitting compound in the polymer film is usually 0.01 to 2% by weight, preferably 0.05 to 0.5% by weight.

[0107] The polymer film has a thickness of usually 30 to 500 nm, preferably 100 to 300 nm. If the thickness of the polymer film is too thin, the amount of emitted light may be insufficient. If the thickness of the polymer film is too large, the driving voltage may become too high, which may be undesirable. Flexibility may be lacking when using a curved or annular body.

[0108] The polymer film is formed by a coating method such as a spin casting method, a coating method, and a dipping method using a solution obtained by dissolving the polymer and the white light-emitting compound according to the present invention in an appropriate solvent. Can be formed.

[0109] When the light-emitting layer 3 is a vapor-deposited film, the thickness of the vapor-deposited film is generally a force that varies depending on the layer structure in the light-emitting layer, etc. 0.1 to LOOnm. When the thickness of the deposited film is too small or too large, the same problem as described above may occur.

[0110] The electrode layer 4 employs a substance having a small work function, and may be formed of a single metal or a metal alloy such as MgAg, aluminum alloy, and metallic calcium. A preferred electrode layer 4 is an alloy electrode of aluminum and a small amount of lithium. The electrode layer 4 is easily formed on the surface including the light emitting layer 3 formed on the substrate 1 by vapor deposition technology, for example. Can be formed.

[0111] Regardless of whether the coating method or the vapor deposition method is used to form the light emitting layer, it is preferable to interpose a nother layer between the electrode layer and the light emitting layer.

[0112] Examples of materials that can form the buffer layer include alkali metal compounds such as lithium fluoride, alkaline earth metal compounds such as magnesium fluoride, oxides such as aluminum oxide, 4, 4, Biscarbazole biphenyl (Cz-TPD). In addition, as a material for forming a noffer layer formed between an anode such as ITO and an organic layer, for example, m-MTDATA (4, 4, 4, 4 "-tris (3-methylphenol-aminoamine) ) Triphenylamine), phthalocyanine, polyarine, polythiophene derivatives, inorganic oxides such as molybdenum oxide, ruthenium oxide, vanadium oxide, and lithium fluoride. By appropriate selection, the driving voltage of the organic EL element, which is a white light emitting element, can be lowered, the quantum efficiency of light emission can be improved, and the emission luminance can be improved.

Next, a second example of the white light emitting device according to the present invention is shown in the drawing. FIG. 2 is an explanatory view showing a cross section of a white light-emitting element which is a multilayer organic EL element.

[0114] As shown in Fig. 2, this white light-emitting element B has a transparent electrode 2, a hole transport layer 5, light-emitting layers 3a and 3b, an electron transport layer 6 and an electrode layer 4 in this order on the surface of the substrate 1. Laminated.

[0115] The substrate 1, the transparent electrode 2, and the electrode layer 4 are the same as those in the white light emitting device A shown in FIG.

[0116] The light emitting layer in the white light emitting device B shown in FIG. 2 includes a light emitting layer 3a and a light emitting layer 3b, and the light emitting layer 3a is a vapor-deposited film of a white light emitting compound in the present invention. The light emitting layer 3b is a DP VBi layer. This DPVBi layer is a layer having a host material function.

[0117] The hole transport materials contained in the hole transport layer 5 include triphenylamine compounds such as N, N, -diphenyl-N, N, -di (m tolyl) -benzidine (TPD), and a Examples include NPD, hydrazone compounds, stilbene compounds, heterocyclic compounds, and π-electron starburst hole transport materials.

[0118] Examples of the electron transport material contained in the electron transport layer 6 include 2- (4-tert-butylphenol) -5- (4 biphenyl) -1, 3, 4 Examples include oxadiazole derivatives such as xadiazole, 2,5 bis (1 naphthyl) 1,3,4 oxadiazole, and 2,5 bis (5 ′ tert butyl-2′-benzoxazolyl) thiophene. Further, as the electron transporting substance, for example, a metal complex material such as quinolinol aluminum complex (Alq3), benzoquinolinol beryllium complex (Bebq2) can be preferably used.

In the white light emitting device B in FIG. 2, the electron transport layer 6 contains Alq3.

[0120] The thickness of each layer is the same as that of a known multilayer organic EL element with conventional strength.

[0121] The white light emitting element B shown in FIG. 2 operates in the same manner as the white light emitting element A shown in FIG. 1, and emits light. Therefore, the white light emitting element B shown in FIG. 2 has the same application as the white light emitting element A shown in FIG.

FIG. 3 shows a third example of the white light emitting device according to the present invention. FIG. 3 is an explanatory view showing a cross section of a white light-emitting element which is a multilayer organic EL element.

A white light emitting device C shown in FIG. 3 is formed by laminating a transparent electrode 2, a hole transport layer 5, a light emitting layer 3, an electron transport layer 8 and an electrode layer 4 in this order on the surface of a substrate 1.

The white light emitting element C shown in FIG. 3 is the same as the white light emitting element B.

FIG. 4 shows another example of a white light emitting element. The white light emitting element D shown in FIG. 4 is formed by laminating a substrate electrode 2, a hole transport layer 5, a light emitting layer 3, and an electrode layer 4 in this order.

In addition to the white light emitting element shown in FIGS. 1 to 4, a hole transport containing a hole transporting substance is provided between an anode as a transparent electrode and a cathode as an electrode layer formed on a substrate. A two-layer organic low-molecular light-emitting device (for example, a hole transport layer and a guest pixel between an anode and a cathode) formed by laminating a layer and an electron transporting light-emitting layer containing a white light-emitting compound in the present invention A two-layer type dye-doped light-emitting device comprising a white light-emitting compound and a light-emitting layer containing a host dye, and a hole transport layer containing a hole-transporting substance between the anode and the cathode. And a two-layer organic light-emitting device (for example, a hole between an anode and a cathode) formed by laminating a white light-emitting compound and an electron-transporting material in the present invention. In this invention, the transport layer and the guest dye A white light emitting compound and an electron transporting light emitting layer containing a host dye, and a hole transporting layer between the anode and the cathode. Examples thereof include a three-layer organic light emitting device formed by laminating a light emitting layer containing a white light emitting compound and an electron transport layer.

[0127] The electron-transporting light-emitting layer in this light-emitting device is usually 50 to 80% polyvinyl carbazole (PVK), 5 to 40% of an electron-transporting light-emitting agent, and the white light-emitting compound according to the present invention. When formed from 0.01 to 20% (by weight), white light emission occurs with high luminance.

[0128] The light emitting layer preferably contains rubrene as a sensitizer, and particularly contains rubrene and Alq3! /.

[0129] The white light-emitting element using the white light-emitting compound according to the present invention can be generally used as, for example, a DC-driven organic EL element, and can also be used as a pulse-driven organic EL element and an AC-driven organic EL element. It can also be used as an element.

Example 1

[0130] (Synthesis of 3-Methyl chloride-9-Ethylcarbazole chloride)

In a 2 L 3 flask, 46.4 g of force rubazole, 100 g of 1 chloroethyl p-toluenesulfonate, 53 g of sodium hydroxide, 40 ml of water and 1200 ml of acetone were placed. The solution in the 3 flask was heated to 60 ° C. for 20 hours with a water bath. After heating for 20 hours, the filtrate obtained by filtration was concentrated and dried to obtain 33 g of pale yellow 9- (2 chloroethyl) carbazole.

[0131] Add 7 lg of paraformaldehyde to a 1-liter three-necked flask, add 250 ml of acetic acid, blow hydrogen chloride gas into the solution in the flask, dissolve paraformaldehyde, and then blow in hydrogen chloride gas. After stopping, an acetic acid solution prepared by dissolving 20 g of the 9- (2 chloroethyl) rubazole in 100 ml of acetic acid was dropped into the flask. The contents of the flask were heated to 50 ° C for 2 hours in a water bath. After the completion of heating for 2 hours, the solid residue obtained by filtering the contents of the flask with a Nuts ヱ washes with methanol, and the solid residue after washing was dried to obtain 3 chloromethyl 9- (2 chloroethyl). ) 21.5 g of force rubazole was obtained.

(Synthesis of white light-emitting compound)

In a triple flask, 3 amino-9 ethylcarbazole 51.0 g, 1,4 dihydroxy-2,5 dimethylcarboxy 1,4-cyclohexagen 25.2 g, ethanol 500 m 1 and 500 ml of acetic acid were added. The solution in the flask was heated to 115 ° C. for 4 hours in a silicone oil bath. After 4 hours of heating, the contents of the triplo flask were allowed to cool and filtered. The liquid obtained by filtration was washed with methanol, and the washed liquid was dried to obtain 48.5 g of a solid.

[0132] Fig. 5 shows the NMR ^ vector chart of the obtained solid. From these, the obtained solid was identified as a compound (cl) having a structure represented by the following formula (cl).

[0133] [Chemical 22]

C ₂ H ₅

[0134] Compound (cl) represented by the above formula (cl) 20. Og and 500 ml of ODB were charged into a flask, 0.5 g of sulfuric acid was added, and the flask was heated to 160 ° C. Heated for hours. After the 1 hour, the contents of the flask were cooled, concentrated and filtered to separate the solids. The solid content was washed successively with water, methanol and petroleum ether and vacuum dried to obtain 18.5 g of the compound (dl) represented by the formula (dl). The NMR chart of this compound (dl) is shown in FIG.

[0135] [Chemical 23]

C H

In a 1000 ml flask, the compound (dl) 4 g N, N-dimethylacetamide (DM AC) 200 ml and 20% aqueous potassium hydroxide solution 10 ml were added. The solution in the three flask was heated to 170 ° C. for 2 hours in a silicone oil bath. After the heating was completed, the contents of the flask were allowed to cool and the pH was adjusted to 2-3. Next, the filtrate obtained by extraction using black mouth form and filtration was concentrated and dried to obtain 2.5 g of a purple solid.

[0137] Fig. 7 shows the NMR ^ vector chart of the obtained solid, and Fig. 8 shows the IR spectrum chart. From these, the obtained solid was identified as a compound (el) having a structure represented by the following formula (el).

[0138] [Chemical 24]

[0139] 25 g of the above compound (el), 0.7 g of pyridine, 50 ml of tetrahydrofuran (THF), and 10 ml of chlorochloride were placed in a three flask. The solution in the flask was heated to 70 ° C. for 20 hours with a silicon oil bath. After the completion of heating, the solution in the triplo flask was allowed to cool and distilled under reduced pressure to obtain 2.9 g of a solid.

[0140] Fig. 9 shows the NMR ^ vector chart of the obtained solid, and Fig. 10 shows the IR spectrum chart. From these, the obtained solid was identified as the compound (f 1) having a structure represented by the following formula (fl).

[0141] [Chemical 25]

[0142] In a triple flask, 2.9 g of the compound (fl), 0.81 g of pyridine, 2.6 lg of 1 hydrazinocarbo-naphthalene and 200 ml of tetrahydrofuran (THF) were added. The solution in the three-flask was heated to 70 ° C for 4 hours in a silicone oil bath. After completion of heating, the solution in Sanfro Flasco was allowed to cool and poured into ice water. The solid obtained by filtering the ice water charge with Nutsche was then washed and dried to give 2.8 g of a brown solid.

[0143] Fig. 11 shows the NMR ^ vector chart of the obtained solid, and Fig. 12 shows the IR spectrum chart. From these, the obtained solid was identified as a compound (gl) having a structure represented by the following formula (gl).

[0144] [Chemical 26]

[0145] A 500 ml pressure bottle was charged with 1.7 g of the compound (gl), 0.44 g of 3 chloromethyl-9 chloroethylcarbazole and 300 ml of N, N dimethylformamide (DMF). The solution in the pressure bottle was heated to 160 ° C. for 20 hours in a silicone oil bath. After heating, the solution in the pressure bottle was allowed to cool and poured into ice water. Subsequently, the solid obtained by filtering the ice water charge with Nutsche was washed and dried to obtain 1.3 g of a solid.

[0146] Fig. 13 shows the NMR ^ vector chart of the obtained solid. From this, the obtained solid was identified as a compound (j 1) having a structure represented by the following formula (j 1).

[0147] [Chemical 27]

[0148] The above compound (j 1) 1. Og and 225 ml of 1,4 dioxane were placed in a 500 ml eggplant flask, and a solution of caustic potash 1. Og dissolved in ethanol was further charged and heated to 100 ° C. Refluxed for 4 hours. After the elapse of 4 hours, the contents of the eggplant flask were cooled, extracted with a black mouth form, and the filtrate obtained by filtration was concentrated and dried to obtain 0.8 g of a purple solid.

[0149] Fig. 14 shows the NMR ^ vector chart of the obtained solid, and Fig. 15 shows the IR spectrum chart. From these, the obtained solid was identified as a compound (1B) having a structure represented by the following formula (1B).

[0150] [Chemical 28]

CH CH ₂

[0151] Into a polymerization tube, 0.5 g of the vinyl compound represented by the above formula (IB) (30 g) DMAC (30 ml) and tungsten hexachloride (2.5 mg) were placed, and the vinyl compound was mixed for 73 hours at room temperature using a shaker. Polymerization was performed. After 73 hours, the content in the polymerization tube was concentrated and filtered, and then the resulting concentrated solution was dried to obtain 0.4 g of a solid. Fig. 16 shows the NMR vector chart of this purple solid. This solid was a polymer having a unit represented by the formula (1C).

[0152] [Chemical 29]

C H— CH9

Further, FIG. 17 shows a fluorescence spectrum chart of the compound having the repeating unit represented by the formula (1C). As a result, it was found that the obtained compound emits white light.

[0154] For the fluorescence spectrum measurement, an F-4500 type spectrofluorometer manufactured by Shimadzu Corporation was used, and the measurement conditions were as follows.

Measurement condition

Measurement mode Wavelength scan

Excitation wavelength dodnm

Fluorescence start wavelength 400nm

Fluorescence end wavelength 700nm

Scan speed 2400nm / min

Excitation side slit 5. Onm Fluorescent side slit 5. Onm

Photomultiplier voltage 700V

Industrial applicability

When the overall shape of the white light emitting element according to the present invention is a large area planar shape, for example, it is attached to a wall surface or a ceiling to provide a large area wall surface white light emitting element and a large area ceiling surface. It can be set as a light emitting lighting device. In other words, the white light emitting element can be used as a surface light source in place of a linear light source such as a conventional fluorescent lamp or a point light source such as a light bulb. In particular, the white light emitting element can emit or illuminate the wall surface, ceiling surface, or floor surface of a residential room, office room, vehicle room, or the like as a surface light source. Furthermore, this white light emitting element can be used for backlights such as a display screen in a computer, a display screen in a mobile phone, and a numeric display screen in a cash register. In addition, this white light-emitting element can be used as various light sources such as direct illumination and indirect illumination, and can be lit at night and has good visibility, an advertising device, a road sign device, It can also be used as a light source such as a reverse lamp in a light-emitting bulletin board and a vehicle such as an automobile. In addition, since this white light emitting element uses mercury, it can be used as a light source that is environmentally friendly instead of a conventional fluorescent lamp using mercury.

Claims

Claims [1] A white light-emitting compound having a structure represented by the following formula (1): [Chemical 1] then £ ~ 1 = then 1

(However, in the formula (1), two R ^{1 s} represent a substituent represented by the following formula (11) or (12), and two Ars represent an aromatic group. In the formula, two R ^{1 s} may be the same or different from each other. Two Ars may be the same or different from each other.

[Chemical 2]

R 2

(However, in the above formula (1-1), R ² represents a hydrogen atom or a halogen atom having 1 to 5 carbon atoms. It may be substituted and represents an alkyl group. )

[Chemical 3]

R ³ R ³

(However, in the formula (1-2), two R ^{3 s} represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. In the formula, two R ^{3 s} are the same as each other. Or it may be different.)

A white light-emitting polymer compound having a monomer unit represented by the formula (11A).

[Chemical 4]

-(CH-CH ₂ )-

[3] According to the following reaction formula 1,

[Chemical 5] K; C1

(a) (b)

(c)

1,4-dihydroxy 2,5 dianolequinolecanolevoxy 1,4-cyclohexagen (a) (wherein R ⁵ in the compound (a) represents an alkyl group) and a phosphorus derivative (b) (wherein, R ¹ in the compound (b), are similar to those ^for R ^1. shown in claim 1), and by heating in a solvent, 1, 4-dihydroxy 2, 5-dialkyl carboxymethyl 1, 4-Shi Compound (c) was synthesized by dehydrating clohexagen ( _a ) and arrin derivative (b),

Then, according to the following reaction formula 2,

[Chemical 6]

Mind ά2

R ΝΗ C00R ⁵ NH COOR ⁵

R 0C R ⁵ 00C NH― R 1

Compound (c) is dehydrogenated to synthesize aromatic compound (d),

Then according to Scheme 3

[Chemical 7]

Anti ίΕ type

R,

By hydrolyzing the aromatic compound (d), a dicarboxylic acid compound (e) was synthesized, and according to the following reaction formula 4,

[Chemical 8] Anti!

Deriving dicarboxylic acid compound (e) to acid halide compound (f),

According to the following reaction formula 5,

[Chemical 9]

Reaction formula 5

R ¹ — NH COX

Ar— CONHN

xoc ,, NH― R ¹

Cf)

! ! I!

0 0

(g) Compound (g) is prepared by reacting acid halide (f) with hydrazide represented by Ar—CONHNH 2 (wherein Ar is the same as R ¹ shown in claim 1). And

Furthermore, according to the following reaction formula 6,

[Chemical 10]

A

I7 ~ r——-

0

The compound (g) is subjected to a ring-closing reaction to be derivatized into an oxadiazole ring-containing compound (h). According to the following reaction formula 7,

[Chemical 11]

Ar

I

N,

——

G

o

G N M

A

Wherein the oxaziazole ring-containing compound (h) is reacted with 3-chloromethyl-9- (2-chloroethyl) -powered rubazole represented by 0 to dehydrohalogenate and demineralize hydrogen. The method for producing a white light-emitting compound according to claim 1.

[4] The method for producing a white light-emitting polymer compound according to [2], wherein the white light-emitting compound represented by the formula (1) is polymerized. [5] A light-emitting device comprising a light-emitting layer containing the white light-emitting compound according to claim 1 or the white light-emitting polymer compound according to claim 2 between a pair of electrodes.