WO2006001198A1

WO2006001198A1 - White organic fluorescent compound

Info

Publication number: WO2006001198A1
Application number: PCT/JP2005/010910
Authority: WO
Inventors: Tadao Nakaya; Atsushi Ikeda; Mitukura Sato
Original assignee: Hirose Engineering Co., Ltd.
Priority date: 2004-06-25
Filing date: 2005-06-15
Publication date: 2006-01-05
Also published as: TW200602477A

Abstract

Disclosed is a white organic fluorescent compound which is a single compound emitting white light with higher luminance. Such a white organic fluorescent compound is fast, excellent in processability and can be used for various white light-emitting bodies such as organic EL devices. Specifically disclosed is a white organic fluorescent compound which is characterized by being represented by the formula (1) below. In the formula (1), R1 represents a C2-C5 alkyl benzyl group, a C1-C5 alkylnaphtho-methyl group or a C1-C5 alkylanthryl methyl group; and R2 represents a hydrogen atom, an alkyl group, an aryl group or an arylalkyl group.

Description

White organic fluorescent compound

Technical field

TECHNICAL FIELD [0001] The present invention relates to a white organic fluorescent compound, and more particularly to a white organic fluorescent compound that has a quinacridone skeleton, is robust, has good processability, and emits white light with high luminance.

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 realized by mixing a red light emitting compound, a blue light emitting compound, a green light emitting compound, and a plurality of light emitting compounds to achieve white light emission. Therefore, as a result of investigations on a single compound that emits white fluorescence, it has become known that a compound having a quinacridone skeleton represented by formula (3) realizes white light emission. It was. Quinacridone is well known as a pigment also called pigment violet 19 and is generally said to be excellent in fastness, weather resistance, light resistance and heat resistance.

[0003] [Chemical 1]

(3)

[0004] For example, the white organic fluorescent compound represented by the formula (1) has been studied as a good light-emitting material for EL devices having a quinacridone skeleton.

[0005] [Chemical 2] O

N

No,

, One o

(i)

Here, several groups are disclosed for R ¹ and R ² . For example, R ¹ is a hydrogen atom, an alkyl group, a benzyl group, etc. Force R ² is an alkyl group. (See Patent Document 1 and Patent Document 2). However, among the compounds represented by the formula (1), the already known white organic fluorescent compounds having the above-mentioned characteristic groups still have difficulties in luminance and lifetime as EL devices. In particular, there was a problem in stably attaching the EL element on the substrate.

[0007] Patent Document 1: JP 2003-192684 A

Patent Document 2: JP 2003-203780 A

Disclosure of the invention

Problems to be solved by the invention

An object of the present invention is to provide a white organic fluorescent compound that can be used for various white light emitters such as an organic EL element. Another object of the present invention is to provide a fluorescent compound suitable as a light emitting material for an EL device having high brightness, high purity white color and long life.

Means for solving the problem

[0009] A first means for solving the above problem is a white organic fluorescent compound represented by the formula (1). R ¹ represents a benzyl group in which a hydrogen atom of a phenyl group is substituted with an alkyl group having 2 to 5 carbon atoms. R ² represents any of a hydrogen atom, an alkyl group, an aryl group or an aryl group.

[0010] [Chemical 3] O

N

No,

, One o

(i)

[0011] A second means for solving the above problem is a white organic fluorescent compound represented by the above formula (1). R ¹ represents a naphthomethyl group in which a hydrogen atom of a naphthyl group is replaced with an alkyl group having 1 to 5 carbon atoms. R ² represents a hydrogen atom, an alkyl group, an aryl group, or an arylenorequinolene group! /.

[0012] A third means for solving the above problem is a white organic fluorescent compound represented by the above formula (1). R ¹ represents an anthrylmethyl group in which a hydrogen atom of an anthryl group (anthryl group) is substituted with an alkyl group having 1 to 5 carbon atoms. R ² represents a hydrogen atom, an alkyl group, an aryl group or an aryl group.

[0013] In the above first to third inventions, R ¹ and R ² may be the same group or different groups. Further, the substituent bonded to the phenyl group, naphthyl group and anthryl group in R ¹ may be one alkyl group or two or more alkyl groups. Further, when there are two or more substituted alkyl groups, they may be the same or different substituents.

The invention's effect

[0014] In the present invention, a white organic phosphor compound suitable as a light-emitting material for high-luminance, high-purity white and long-life EL elements that can be used for various white light emitters including organic EL elements and the like. Can provide. In particular, it is well suited for the production of stable EL elements that adhere well on the substrate as EL elements.

Brief Description of Drawings

FIG. 1 is an IR chart of compound (13) in Example 1.

FIG. 2 is an NMR chart of the compound (13) in Example 1.

[FIG. 3] FIG. 3 shows the fluorescence spectrum of the white organic fluorescent compound (14) of Example 1. is there.

FIG. 4 is an IR chart of the compound (15) in Example 2.

FIG. 5 is an NMR chart of the compound (15) in Example 2.

FIG. 6 is an IR chart of the white organic fluorescent compound (16) in Example 2.

FIG. 7 is an NMR chart of white organic fluorescent compound (16) in Example 2.

FIG. 8 is a graph showing the fluorescence spectrum of the white organic fluorescent compound (16) of Example 2.

FIG. 9 is an IR chart of the compound (19) in Example 3.

FIG. 10 is an NMR chart of the compound (19) in Example 3.

FIG. 11 is an IR chart of the compound (20) in Example 3.

FIG. 12 is an NMR chart of the compound (20) in Example 3.

FIG. 13 is an IR chart of the compound (21) in Example 3.

FIG. 14 is an IR chart of the white organic fluorescent compound (22) in Example 3.

FIG. 15 is a graph showing the fluorescence spectrum of the white organic fluorescent compound (22) of Example 3.

FIG. 16 is an explanatory view showing an example of an organic EL element.

Explanation of symbols

[0016] 1 · · Organic EL device

2 'PCB

3'Anode

4.Light emitting layer

5 · · Cathode

BEST MODE FOR CARRYING OUT THE INVENTION

[0017] As described above, a compound having a quinacridone skeleton, such as a white organic fluorescent compound represented by the general formula (1), can be used as an EL device. As described above, some of R ¹ and R ² have already been used. Such groups are disclosed. Thus, as a result of examining these compounds in more detail, the present inventors obtained a particularly excellent white organic fluorescent compound for EL devices by optimally selecting the characteristic group R ¹ bonded to the nitrogen atom of quinacridone. I was able to. The In other words, the quinacridone skeleton was distorted by utilizing steric hindrance and electron donating property in the molecule, and the luminescence function was adjusted. As a result, the inventors have invented a white light-emitting material that enhances light emission on the low wavelength side, which is relatively difficult to emit light, and sufficiently develops red light emission and is well-balanced or has adjusted light emission characteristics.

[0018] The white organic fluorescent compound represented by the formula (1) according to the present invention has a quinacridone skeleton represented by the formula (3). This quinacridone is well known as a pigment called Pigment Violet 19, which is synthesized by, for example, condensation, ring closure and acidification using, for example, jetyl succinyl succinate and arrin as main raw materials. Therefore, the white organic fluorescent compound according to the present invention is also excellent in fastness, weather resistance, light resistance and heat resistance.

In the formula (1), R ¹ is a benzyl group in which a hydrogen atom of a phenyl group is substituted with an alkyl group having 2 to 5 carbon atoms, or a hydrogen atom of a naphthyl group is an alkyl group having 1 to 5 carbon atoms. An anthrylmethyl group (anthrylmethyl group) in which a hydrogen atom of a naphthomethyl group or anthryl group (anthryl group) substituted with an alkyl group having 1 to 5 carbon atoms is substituted. Two R ¹ may be the same or different.

[0020] When R ¹ is a substituted benzyl group, the hydrogen atom of the phenyl group is substituted with an alkyl group having 2 to 5 carbon atoms. This alkyl group having 2 to 5 carbon atoms is a characteristic group selected from an ethyl group, a propyl group, a butyl group, and a pentyl group. The propyl group, butyl group and pentyl group may each be linear or branched. Branched characteristic groups such as isopropyl and tertiary butyl groups are preferred. In addition, the substitution position on the phenyl group may be anywhere, but the ortho and para positions are suitable. This is probably because the electron donating effect of the benzyl group is strong. Two or more alkyl groups may be substituted for the hydrogen atom of the phenyl group. In this case, the same or different substituents may be used.

[0021] As described above, by selecting a characteristic group that binds to the nitrogen atom of the quinacridone skeleton, the quinacridone skeleton, or even the entire molecule, has a steric or electronic state due to steric hindrance or electron donating properties in the molecule. The light emission function changes. As a result, light emission on the low wavelength side, which is considered to be relatively difficult to emit light, is increased, so that red light emission is sufficiently developed and a balanced white light-emitting material can be obtained. The reason why the substituent alkyl group is 5 or less carbon atoms is that if the alkyl group becomes too large, the light emitting device per molecule Even if the performance is the same, the light emitting function per weight will be reduced. In addition, if the molecular weight is too large, production and handling as a compound becomes difficult.

[0022] When R ¹ is a substituted naphthomethyl group, the hydrogen atom of the naphthyl group is a naphthomethyl group substituted with an alkyl group having 1 to 5 carbon atoms. This alkyl group having 1 to 5 carbon atoms is a characteristic group in which methyl, ethyl, propyl, butyl, and pentyl groups are also selected. The substituted naphthomethyl group may be either (X naphthomethyl group or β-naphthomethyl group. As in the case of the above benzyl group, when the alkyl group as a substituent is a propyl group, a butyl group, or a pentyl group, each is linear or branched. Furthermore, the substitution position of the alkyl group to the naphthyl group may be anywhere, and more than two alkyl groups may be substituted for the hydrogen atom of the naphthyl group. As described above, when the characteristic group bonded to the nitrogen atom of the quinacridone skeleton is a substituted naphthomethyl group, the quinacridone skeleton is distorted due to steric hindrance and electron donating properties in the molecule, and As a result, the light emission on the low wavelength side, which is considered to be relatively difficult to emit light, increases, and the red light emission is fully developed and balanced. If the alkyl group as a substituent is 5 or less carbon atoms, if the alkyl group is too large, the light emission function per weight will drop even if the light emission function per molecule is the same. In addition, if the molecular weight is too large, manufacture and handling as a compound becomes difficult.

[0023] When R ¹ is a substituted anthrylmethyl group, the hydrogen atom of the anthryl group is an anthrylmethyl group substituted with an alkyl group having 1 to 5 carbon atoms. This alkyl group having 1 to 5 carbon atoms is a characteristic group selected from a methyl group, an ethyl group, a propyl group, a butyl group, and a pentyl group. As in the case of the benzyl group, when the alkyl group as a substituent is a propyl group, a butyl group, or a pentyl group, each may be linear or branched. Furthermore, the substitution position of the alkyl group to the anthryl group may be anywhere. Two or more alkyl groups may be substituted for the hydrogen atom of the anthryl group. In this case, the same substituent or different substituents may be used. As described above, by using a substituted anthrylmethyl group as a characteristic group bonded to the nitrogen atom of the quinacridone skeleton, the quinacridone skeleton is distorted due to steric hindrance and electron donating properties in the molecule, and the luminescence function changes . This makes it relatively difficult to emit light. Therefore, red light emission is sufficiently developed and a balanced white light emitting material can be obtained. The reason why the substituent alkyl group is 5 or less carbon atoms is that if the alkyl group becomes too large, the light emitting function per weight will be lowered even if the light emitting function per molecule is the same. If the molecular weight is too large, it is difficult to manufacture and handle as a compound.

In the formulas (1) of the first to third inventions, the two characteristic groups R ² are each a hydrogen atom, an alkyl group, an aryl group or an aryl group, each of which is the same group May be different groups. Examples of the alkyl group include an alkyl group having 1 to 30 carbon atoms, and a lower alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, and a propyl group is particularly preferable. . The two characteristic groups R ² may be the same or different. When R ² is an aryl group, the aryl group includes a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a substituent such as an alkyl group or an alkoxy group bonded to these aromatic rings. Examples thereof include a p-tolyl group and a p-alkoxyphenol group. When R ² is an arylalkyl group, the arylalkyl group includes a benzyl group, a 1-phenylethyl group, a 2-phenylethyl group, a 1-phenylpropyl group, a 2-phenylpropyl group, 3 Examples thereof include a phenylpropyl group and a 4-phenylbutyl group. The phenyl group may be further substituted with a substituent such as an alkyl group. Preferred arylalkyl groups are benzyl group and p-methylbenzyl group.

[0025] The white organic fluorescent compound represented by the formula (1) of the third invention of the first force is

By having the substituent of R ² , solubility in a solvent is improved, and therefore, coating property by dissolving in an appropriate solvent is improved, and sublimation temperature is lowered, so that workability by vapor deposition is improved. Furthermore, the compatibility with the polymer compound is improved, so that it can be included in the polymer film. In particular, by selecting R ¹ , it is an excellent white organic fluorescent compound with particularly improved emission luminance, sublimation temperature, and compatibility with a polymer compound when an EL device is obtained.

[0026] The white organic fluorescent compound represented by the formula (1) can be produced, for example, according to the following reaction formula.

[0027] [Chemical 4]

In the above formula, R is a lower alkyl group such as a methyl group or an ethyl group, and R ¹ and R ² are the same characteristic groups as described above. The above reaction formula is, for example, dialkyl 2,5 dihydroxy 1,4-cyclohexadiene 1,4-dicarboxylate (compound (4) in the above reaction formula) and a compound (5) such as 3-amino-9 alkyl strength rubazole. The reaction proceeds by heating in an appropriate solvent. A dehydration reaction proceeds to obtain a compound (6) crosslinked with an amino group. In the dehydration reaction, an appropriate dehydrating agent such as concentrated sulfuric acid can be used.

[0029] When the dehydration reaction product is further treated with concentrated sulfuric acid or the like, a dehydrogenation reaction occurs as shown in the following formula.

[0030] [Chemical 5]

R ¹

R 2 [0031] When R ¹ is hydrogen, the dehydrogenation reaction product (7) is, for example, I ^ HaU in DMF, where HaL represents a halogen atom. ) Can be reacted to alkylate the dehydrogenation reaction product (7).

[0032] Next, a ring-closing reaction is carried out according to the following reaction formula.

[0033] [Chemical 6]

(8)

[0034] The ring closure reaction is carried out by heating in an appropriate solvent, preferably in the presence of an organic acid catalyst such as sulfuric acid or p-toluenesulfonic acid, in an appropriate solvent such as dichlorobenzene in an inert high-boiling organic solvent. It progresses by heating with. As a ring-closed compound, there is a white organic fluorescent compound containing a force rubazole skeleton represented by the above formula (8). The compound power represented by (8) in the above reaction formula is the white organic fluorescent compound according to the present invention represented by the above formula (1).

The white organic fluorescent compound according to the present invention emits light in the region of 400 to 700 nm and can be used for an organic EL device capable of emitting white light.

[0036] The organic EL device using the white organic fluorescent compound of the present invention comprises an ITO anode, polybulur rubazole (PVK), 2- (4 tert butylphenol) 5- (4-biphenyl) -1, 3 4, 4 Oxadiazole and a white organic fluorescent compound-containing light emitting layer and a cathode formed on the surface of the light emitting layer may be used. For light emission, when an electric field is applied between the cathode and the cathode, electrons are injected from the cathode side, holes are injected from the anode side, and electrons are recombined with holes in the light emitting layer. However, the energy level is conduction band power It is a phenomenon in which energy is released as light when returning to the child band.

[0037] This organic EL element can employ various types of structures as long as it has a light emitting layer containing a white organic fluorescent compound according to the present invention between an anode and a cathode. As this organic EL element, for example, as shown in FIG. 16, the transparent electrode 3 formed on the surface of the transparent substrate 2 and the white electrode according to the present invention formed on the surface of the transparent electrode 3 are used. A single-layer organic light emitting device comprising a light emitting layer 4 containing an organic fluorescent compound and a cathode 5 formed on the surface of the light emitting layer 4 can be mentioned.

[0038] In this one-layer type organic light emitting device, the light emitting layer can be a deposited layer formed by depositing a white organic fluorescent compound represented by the above formula (1). A light emitting layer obtained by dissolving the white organic fluorescent compound of the present invention shown in (1) above in an organic solvent together with a polymer compound such as polybulur rubazole, applying the polymer solution obtained, and drying It's a monkey.

[0039] As another type of organic EL device, an electron transporting material that transports electrons between the anode and the cathode, the white organic fluorescent compound according to the present invention, and a hole transporting hole. A single-layer organic light-emitting device having a light-emitting layer containing both a hole-transporting polymer, a hole-transporting layer containing a hole-transporting substance between the anode and the cathode formed on the substrate, and the present invention A two-layer organic low-molecular light-emitting device formed by laminating such a white organic fluorescent compound-containing electron transporting light emitting layer (for example, a hole transporting layer between an anode and a cathode, and a white color according to the present invention as a guest dye) A two-layer dye-doped light-emitting device in which a light-emitting layer containing an organic fluorescent compound and a host dye is stacked), a hole transport layer containing a hole-transporting substance between the anode and the cathode, White organic fluorescent compound and electron according to the invention A two-layer organic light-emitting device formed by laminating an electron-transporting light-emitting layer formed by co-evaporation with a substance having a transportability (for example, a hole transport layer and a guest dye according to the present invention A two-layer dye-doped organic light-emitting device comprising a white organic fluorescent compound and a host dye, and a hole transport layer between the anode and the cathode; the white organic according to the present invention; A three-layer organic light-emitting element formed by laminating a light-emitting layer containing a fluorescent compound and an electron transport layer can be given. In the various organic EL devices described above, a single light emitting layer and a laminate composed of two layers and three layers may be referred to as an organic layer. [0040] The organic EL element can usually be formed on a substrate. Examples of this substrate include transparent substrates such as glass and plastic. The anode can be made of various materials as long as it has a large work function and is transparent, and holes can be injected into the film by applying a voltage. Specifically, as the anode, ITO, In

2

Inorganic transparent conductive materials such as O, SnO, ZnO, CdO, etc., and their compounds, and poly

3 2

It can be formed of a conductive polymer material such as phosphorus. This anode is formed on the substrate by chemical vapor deposition, spray pie-lysis, vacuum deposition, electron beam deposition, sputtering, ion beam sputtering, ion plating, ion assisted deposition, It can be formed by other methods.

[0041] The cathode employs a material having a small work function, and may be formed of a single metal or a metal alloy such as MgAg, aluminum alloy, and calcium metal. A preferred cathode is an alloy electrode of aluminum and a small amount of lithium. The cathode can be easily formed on the surface of the organic layer including the light emitting layer formed on the substrate, for example, by a vapor deposition technique.

[0042] Examples of the electron transporting substance include 2- (4-tert-butylphenol) -5- (4-biphenyl) 1,3,4-oxadiazole derivatives and the like, and 2, 5 bis (1 naphthyl) 1,3,4 oxadiazole, 2,5 bis (5′-tert-butyl-2′-benzoxazolyl) thiophene, and the like. Further, as the electron transporting substance, for example, a metal complex material such as quinolinol aluminum complex (Alq3) or benzoquinolinol beryllium complex (Bebq2) can be preferably used.

[0043] Examples of the hole transport material include triphenylamine compounds such as N, N'-diphenyl-N, N, 1di (m tolyl) 1benzidine (TPD), and α-NPD, hydrazone compounds, Examples include stilbene compounds, heterocyclic compounds, and π-electron starburst hole transport materials.

[0044] The organic layer in the organic EL element can be formed by any one of a coating method such as a spin casting method, a coating method, a dip method, and a vapor deposition method. Whichever of the coating method and the vapor deposition method is adopted, it is preferable to interpose a buffer layer between the electrode and the organic layer. Forming the buffer layer formed between the cathode and the organic layer; Examples of materials that can be used include, for example, alkali metal compounds such as lithium fluoride, alkaline earth metal compounds such as magnesium fluoride, acid compounds such as acid aluminum, 4, 4, 1 bis carbazole biphenol (Cz-TPD). In addition, for example, m-MTDA TA (4, 4 ,, 4 "-tris (3-methylphenol-lamino) is used as a material for forming a buffer layer formed between an anode such as ITO and an organic layer. (Triphenylamine), lid opening, polyarine, polythiophene derivatives, inorganic oxides such as molybdenum oxide, ruthenium oxide, vanadium oxide, and lithium fluoride. By appropriately selecting the material, the driving voltage of the organic EL element can be lowered, the quantum efficiency of light emission can be improved, and the emission luminance can be improved.

[0045] The electron-transporting light-emitting layer in this light-emitting element is usually 50 to 80% polyvinyl carbazole (PVK), 5 to 40% of an electron-transporting light-emitting agent, and the white organic fluorescent material according to the present invention. When formed with 0.01 to 20% (by weight) of compound, white light emission occurs with high brightness. Examples of the hole transporting polymer include polyvinylcarbazole and poly (3-alkylenephene). The organic layer preferably contains rubrene as a sensitizer, and particularly preferably contains rubrene and Alq3.

[0046] The organic EL device using the white organic fluorescent compound according to the present invention can be generally used as, for example, a direct current drive device, and can also be used as a pulse drive device and an AC drive device. Can be used.

[0047] The white organic fluorescent compound according to the present invention is further used in the display field such as a monochrome display and a color display, and in the lighting field such as a light sign, a direct-view sign, indirect illumination, and an LCD backlight.

Example

[0048] (Example 1)

To a 1000 ml three-necked flask, add 25.0 g (1.2 X 10 ^_1 mol) of 3-amino-9-ethylcarbazole and 13.6 g (6.0 X 10 ^_2 mol) of the compound represented by the formula (10). 200 ml each of chilled alcohol was added. Heat to 120 ° C using a silicone oil bath Stir and react for 4 hours. After completion of the reaction, the reaction mixture was cooled to room temperature and poured into ice.

[0049] [Chemical 7]

[0050] This was filtered using a glass filter. The solid matter remaining in the filter was washed successively with methyl alcohol cooled to 5 ° C. and petroleum ether, and then dried in vacuo to obtain a longa powder (35.2 g). This brick-colored powder is represented by the following formula (11).

[0051] [Chemical 8]

H C 2 5

[0052] <Dehydrogenation reaction>

Place 25.0 g of the powder (11) obtained in the above dehydration reaction in a 1000 ml three-necked flask, add 500 ml of o-dichloromouth benzene, and slowly drop 95% sulfuric acid l.Og at room temperature for 30 minutes. After stirring, the mixture was heated and stirred up to 160 ° C using a silicone oil bath and reacted for 2 hours. After completion of the reaction, it was cooled to room temperature and placed in ice. Using a separatory funnel, extraction of the black mouth form was performed three times, followed by washing with water twice, and after removing sodium sulfate and removing water, the solution was filtered and concentrated to dryness using an evaporator. The obtained solid was sequentially washed with ethyl acetate and petroleum ether, and then vacuum-dried to obtain a red powder (13.1 g). This red powder is expressed by the following formula (12).

[0053] [Chemical 9] HS

[0054] <Methylnaphthomethylation reaction>

The compound having the structure represented by the formula (12) 5.0 g (8. 49 X 10 ^_3 mol) was put into a 1000 ml pressure bottle, and 4-methyl 1-chloromethylnaphthalene (CH CH CH Cl) 9.7 g (

3 10 6 2

5.09 X 10- ² mol) was added, further, N, N-dimethylformamide (DMF) 400 ml was Karoe. The mixture was heated and stirred to 160 ° C using a silicone oil bath and reacted for 20 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, concentrated using an evaporator, and then filtered through a glass filter. The obtained solid was washed with water, methyl alcohol, and petroleum ether and then vacuum-dried to obtain 6.8 g of a brick colored powder. Fig. 1 shows the IR chart of this brick powder, and Fig. 2 shows the NMR chart. This brick-colored powder is represented by the following formula (13).

[0055] [Chem. 10] ^ 5

[0056] However, X represents a 4-methyl-1-naphthomethyl group (CH C H CH—).

3 10 6 2

Three-necked flask 500ml putting the bricks Irokotai (13) 6.0g (6.53 X 10- 3 mol), p - toluenesulfonic acid monohydrate 7. 5 g of (3.94 X 10- ² mol) was added, In addition, o I got 200ml. The mixture was stirred and heated to 160 ° C using a silicone oil bath for 20 hours. After completion of the reaction, the mixture was concentrated to dryness using an evaporator. The obtained solid was washed with methyl alcohol, acetone and petroleum ether cooled to 5 ° C. and then vacuum-dried to obtain 3.9 g of a black powder. This black powder is the white organic fluorescent compound of the present invention represented by the following formula (14).

[0057] [Chemical 11]

[0058] However, X represents a 4-methyl-1-naphthomethyl group (CH C H CH-).

3 10 6 2

The white organic fluorescent compound (14) was dissolved in mixed xylene to a concentration of lOmgZL to prepare a sample solution. This sample solution was loaded into an F-4500 spectrofluorometer manufactured by Shimadzu Corporation, and the fluorescence spectrum was measured under the following conditions. The resulting fluorescent spectrum is shown in FIG.

Measurement condition

Measurement mode Wavelength scan

Excitation wavelength 365nm

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

As can be seen from FIG. 3, the white organic fluorescent compound obtained in this example is 400 700 nm. Fluorescence can be seen, covering the entire area.

(Example 2)

<t-Butylbenzylation reaction>

The compound represented by the manufactured formula (12) in Example 1 5. 0 g of (8. 49 X 10- ³ mol) was placed in而圧bottle 1000 ml, 4-t-butylbenzyl bromide 9. 3 g (5 09 X 10 ^_2 mol) was added, and then 400 ml of N, N-dimethylformamide (DMF) was added. Using a silicone oil bath, the pressure bottle was heated to 160 ° C with stirring and allowed to react for 20 hours. After completion of the reaction, the mixture was cooled to room temperature, concentrated using an evaporator, poured into ice water, and neutralized with sodium hydroxide. Using a separatory funnel, black mouth form extraction was performed three times, and water washing was performed twice. Next, sodium sulfate was added to remove water, filtered, and concentrated to dryness using an evaporator. The obtained solid was washed with petroleum ether and then vacuum dried to obtain 3.4 g of powder. Fig. 4 shows the IR chart of this powder, and Fig. 5 shows the NMR chart. This brown powder has a structure represented by the formula (15).

[Chemical 12]

(Ten)

Y represents a 4-tbutylbenzyl group (4- (CH 3) CC H CH—).

3 3 6 4 2

In a 500 ml three-necked flask, the compound represented by the above formula (15) 3. Og (3.32 X 10 " ³ mol) was put, and p-toluenesulfonic acid monohydrate 3.8 g (2. 00 X 10 ^_2 mol) was added, and 250 ml of o-dichlorobenzene was added, and the mixture was stirred and heated to 160 ° C in a silicone oil bath for 20 hours, after which the reaction was concentrated to dryness using an evaporator. The obtained solid was washed with methyl alcohol, acetone and petroleum ether cooled to 5 ° C., and then vacuum-dried to obtain a solid, and 1.0 g of the solid was oxidized using a Soxhlet extraction apparatus. Extracted with 250 ml of Ren over 24 hours. After completion of extraction, the mixture was concentrated to dryness using an evaporator, and the resulting solid was washed with petroleum ether and vacuum dried to obtain 2.5 g of powder. Fig. 6 shows the IR chart of this powder, and Fig. 7 shows the NMR chart. This solid was a white organic fluorescent compound having a structure represented by formula (16).

[0061] [Chemical 13]

2 Η 5 '(1 6)

[0062] However, Y represents a 4-tbutylbenzyl group (4- (CH) CC H CH-).

3 3 6 4 2

In a 5 ml volumetric flask, weigh 70 mg of polycarbcarbazole, 29 mg of t-butylphenol-ludiphenol, 29 mg of 1,3,4-oxazadiazole, and 1 mg of white organic fluorescent compound (16), and store dichloroethane. Instead of preparing a white organic fluorescent compound (16) -containing solution so as to be 5 ml, in a 5 ml volumetric flask is added 70 mg of polycarbcarbazole, 29.7 mg of BND having the structure represented by the formula (17) and the above formula ( A white organic fluorescent compound-containing solution was prepared so that 0.3 mg of white organic fluorescent compound represented by 16) was added to dichloroethane to 5 ml. This white organic fluorescent compound-containing solution was made sufficiently uniform by irradiating ultrasonic waves with an ultrasonic cleaner (US-2, manufactured by SND Corporation) for 20 minutes. On the other hand, an ITO substrate (50 × 50 mm, Sanyo Vacuum Industries Co., Ltd.) was ultrasonically cleaned with acetone for 10 minutes, then ultrasonically cleaned with 2-propanol for 10 minutes, and blown with nitrogen to dry. After that, UV irradiation was performed for 30 seconds with a UV irradiation device (manufactured by M'D Excimer, wavelength 172 nm) for cleaning. The prepared white organic fluorescent compound-containing solution is dropped onto an ITO substrate that has been cleaned and dried using a spin coater (Mikasa Co., Ltd., 1H-D7), and the rotational speed is 1,500 rpm and the rotational time is A film was formed by spin coating in 3 seconds. The deposited substrate was dried in a thermostatic chamber at 50 ° C for 30 minutes, and then vacuum deposition equipment (Daia Vacuum Engineering Co., Ltd.) Ltd., VDS- M2- 46 type) in aluminum alloy (Al: Li = 99: l weight ratio, Inc. manufactured by Pure Chemical Laboratory) electrode was deposited to a thickness of about 150nm at 4 X 10- ⁶ Torr An EL device was manufactured. The luminance and chromaticity of this EL element were measured with a spectroradiometer SR-3 manufactured by Topcon Corporation.

[0063] [Chemical 14]

As a result, the voltage was 12.5 V, the current was 18.8 mA, the luminance was 12000 CdZm ² , and the chromaticity X was 0.

A result of 33 and chromaticity Y of 0.33 was obtained. From this spectral radiance graph, it can be recognized that the white light was sufficiently emitted by the naked eye.

[0065] <Luminescent characteristics (3)>

The white organic fluorescent compound (16) was dissolved in mixed xylene to a concentration of lOmgZL to prepare a sample solution. This sample solution was loaded into an F-4500 spectrofluorometer manufactured by Shimadzu Corporation, and the fluorescence spectrum was measured under the following conditions. The resulting fluorescent spectrum is shown in FIG.

[0066] Measurement conditions

Measurement mode Wavelength scan

Excitation wavelength 365nm

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

As can be seen from FIG. 8, the white organic fluorescent compound obtained in this example is 400 to 700 nm. Fluorescence can be seen, covering the entire area. In particular, there is a large peak at 562 nm.

[0067] (Example 3)

3-Amino-9- (p-tolyl) force rubazole in a 500 ml 3-neck flask 3.6 g (l. 32 X 1 0 ^_2 mol) and the compound represented by formula (10) 1.4 g (6.13 X 10 ^_3 mol ) And 100 ml each of acetic acid and ethyl alcohol. The mixture was heated and stirred to 120 ° C using a silicone oil bath and reacted for 4 hours. After completion of the reaction, the reaction mixture was cooled to room temperature and poured into ice.

[0068] [Chemical 15]

■ I

[0069] This was filtered using a glass filter. The solid matter remaining in the filter was washed successively with methyl alcohol cooled to 5 ° C. and petroleum ether, and then vacuum-dried to obtain a red powder (3. lg). Fig. 9 shows the IR chart of this red powder, and Fig. 10 shows the NMR chart. This red powder is represented by the following formula (19).

[0070] [Chemical 16]

[0071] <Dehydrogenation reaction>

In a 500 ml three-necked flask, put 1.3 g of the powder (19) obtained in the above dehydration reaction, add 250 ml of o-dichlorobenzene, gradually drop 2 drops of 95% sulfuric acid at room temperature and stir for 30 minutes. After that, the mixture was heated and stirred up to 160 ° C using a silicone oil bath and reacted for 1 hour. After completion of the reaction, it was cooled to room temperature and put into ice. Extraction was performed three times using a separatory funnel, followed by washing twice with water, followed by sodium sulfate addition and removal of the water, filtering, and concentrating to dryness using an evaporator. The obtained solid was sequentially washed with ethyl acetate and petroleum ether, and then dried under vacuum to obtain a red powder (1.3 g). Fig. 11 shows the IR chart of this brick colored powder, and Fig. 12 shows the NMR chart. This red powder is represented by the following formula (20).

[0072] [Chemical 17]

[0073] <t-butylbenzylation reaction>

1. 28 g (l. 74 X 10 ^_3 mol) of the compound represented by the formula (20) prepared above was put in a 500 ml pressure bottle, and 4-90-butylbenzyl bromide 1.90 g (l. 04 X 10 mol) was added and then 200 ml of N, N-dimethylformamide (DMF) was added. Using a silicone oil bath, the inside of the pressure bottle was heated to 160 ° C with stirring and allowed to react for 18 hours. After completion of the reaction, the mixture was cooled to room temperature, concentrated using an evaporator, poured into ice water, and neutralized with sodium hydroxide. Using a separatory funnel, black mouth form extraction was performed three times, followed by washing with water twice. Next, add sodium sulfate to remove moisture, filter, Concentrate to dryness using an evaporator. The obtained solid was washed with petroleum ether and then vacuum dried to obtain a powder. An IR chart of this powder is shown in FIG. This powder has a structure represented by formula (21).

[0074] [Chemical 18]

[0075] However, X represents a 4-tbutylbenzyl group (4- (CH) CC H CH-).

3 3 6 4 2

In a 500 ml three-necked flask, 0.61 g (5.94 X 10 " ⁴ mo 1) of the compound represented by the above formula (21) was placed, and P-toluenesulfonic acid monohydrate 0.668 g (3.57 X 10 ^_3 mol) was added, and 200 ml of dichlorobenzene was added, and the mixture was vigorously heated to 160 ° C in a silicone oil bath and allowed to react for 20 hours, after which the reaction was concentrated using an evaporator. The solid obtained was washed with methyl alcohol, acetone and petroleum ether cooled to 5 ° C., and then dried in vacuo to obtain a solid, and 1.0 g of the solid was collected using a Soxhlet extraction apparatus. Extracted with 250 ml of silene over 24 hours, concentrated to dryness using an evaporator after completion of extraction, and the resulting solid was washed with petroleum ether and vacuum dried to obtain 0.5 g of a black powder. Fig. 14 shows the IR chart of the body, and Fig. 15 shows the fluorescence spectrum measured in the same manner as in Example 1. Indicated. The solid was filed white organic fluorescent compounds having the structure shown by the formula (22).

[0076] [Chemical 19]

[0077] However, X represents a 4-tbutylbenzyl group (4- (CH) CC H CH-).

3 3 6 4 2

As can be seen from FIG. 15, the white organic fluorescent compound (22) obtained in this example shows fluorescence emission at 400 to 700 nm and covers the entire region. In particular, there are large peaks not only on the short wavelength side but also on the long wavelength side of 555 nm and 595 nm.

Industrial applicability

[0079] The white organic fluorescent compound of the present invention can be used to emit white light by an organic EL element, a display, a lighting device, or the like. In addition, the white organic fluorescent compound can be made into a light emitting element capable of emitting blue light, red light and green light by spectroscopic analysis using a prism, and further, a full color display can be performed using a color filter. It can also be used for LCD backlights.

Claims

Claims [1] A white organic fluorescent compound represented by the following formula (1):

[Chemical 1]

(However, R ¹ represents a benzyl group in which the hydrogen atom of the full group is substituted with an alkyl group having 2 to 5 carbon atoms, and R ² represents a hydrogen atom, an alkyl group, an aryl group, or an aryl alkyl group. Show.)

[2] A white organic fluorescent compound represented by the following formula (1):

[Chemical 2]

(However, R ¹ represents a naphthomethyl group in which a hydrogen atom of a naphthyl group is substituted with an alkyl group having 1 to 5 carbon atoms, and R ² represents a hydrogen atom, an alkyl group, an aryl group, or an aryl alkyl group. )

[3] A white organic fluorescent compound represented by the following formula (1):

However, R ¹ represents a anthrylmethyl group in which a hydrogen atom is substitution with an alkyl group having 1 to 5 carbon atoms anthryl group (Anthryl group) (anthrylmethyl group), R ² represents a hydrogen atom, an alkyl group, _n indicating the Ariru group or § reel alkyl group