JP2554771B2 - Aromatic dimethylidin compound - Google Patents

Description

TECHNICAL FIELD The present invention relates to an aromatic dimethylidyne compound and a method for producing the same, and more specifically, a novel aromatic dimethylidene compound useful as a light emitting material for an electroluminescence (EL) device and the like. The present invention relates to an efficient manufacturing method.

[Problems to be Solved by Prior Art and Invention]

Focusing on the high fluorescence efficiency of organic compounds, EL of organic compounds
The research of the device utilizing the performance has been done for a long time. For example, W. Helfrish, Dresmer, Williams et al. Obtained blue emission using anthracene crystal (J. Chem. Phys., 44 , 29.
02 (1966)). Further, Vincett and Barlow et al. Manufacture a light emitting device by a vacuum evaporation method of a condensed polycyclic aromatic compound (Thin Solid Films, 99 , 171 (1982)).

However, in all cases, only low emission brightness and low emission efficiency have been obtained.

Recently, using tetraphenyl butadiene as a light emitting material
It has been reported that a blue light emission of 100 cd / m ² was obtained (JP-A-59-194393). Furthermore, it has been reported that a green light emitting organic thin film EL device with a brightness of 1000 cd / m ² or more was developed by stacking a hole conductive diamine compound and a fluorescent aluminum chelate complex as a light emitting material (Appl. Phys. Lett., 51 , 913 (1987)).

Further, the distyrylbenzene compound, which is famous as a laser dye, has high fluorescence in the blue to blue-green region, and using this as a light emitting material, it was possible to obtain EL emission of about 80 cd / m ^{2 in a} single layer. It has been reported (European patent 0319881).

However, under the present circumstances, a high-luminance and high-efficiency light-emitting material having a luminance of 1000 cd / m ² or more has not yet been obtained in a color other than green (especially in a blue system).

Further, regarding a photoreceptor characterized by containing a distyryl compound, it is shown in JP-A-63-269158, the compound shown here, the central portion is an unsubstituted phenyl group, It is clear that when an EL element is prepared using as a light emitting material, crystallization proceeds and the thin film property deteriorates.

Therefore, the inventors of the present invention have conducted extensive studies to develop a compound that can obtain high-luminance EL emission with a luminance of 1000 cd / m ² or more in a region from blue-violet to green (in particular, blue).

[Means for solving the problem]

As a result, they have found that a novel aromatic dimethylidene compound having a specific substituent is suitable for the above purpose. The present invention has been completed based on such findings.

That is, the present invention relates to the general formula [Wherein R ^{1 to} R ⁴ are alkyl groups having 1 to 6 carbon atoms, phenyl groups, p-alkyl substituted phenyl groups, p-phenyl substituted phenyl groups, p-methoxy substituted phenyl groups, p-phenoxy substituted phenyl groups, p-halogen-substituted phenyl group, biphenyl group,
A naphthyl group, a pyridyl group or a cyclohexyl group is shown. R ^{1 to} R ⁴ may be the same or different from each other. Ar represents a 2,5-dialkyl-substituted phenylene group, a biphenylene group, a 3,3'-dialkyl-substituted biphenylene group, a naphthylene group or an anthracenediyl group. ] An aromatic dimethylidene compound represented by the following formula is preferably provided, wherein R ^{1 to} R ⁴ in the above formula (I) are preferably a methyl group, a phenyl group, a p-alkyl-substituted phenyl group, and a p-phenyl-substituted phenyl group, respectively. A group, a p-methoxy-substituted phenyl group, a p-phenoxy-substituted phenyl group, a p-bromo-substituted phenyl group, a cyclohexyl group or a pyridyl group,
The present invention provides an aromatic dimethylidene compound in which Ar is a 2,5-dimethyl-substituted phenyl group, a naphthylene group, a biphenylene group, a 3,3'-dimethyl-substituted biphenylene group or an anthracenediyl group.

Here, R ^{1 to} R ⁴ in the general formula (I) may be the same as or different from each other as described above, and each represents an alkyl group having 1 to 6 carbon atoms (methyl group, ethyl group, n-propyl group, i- Propyl group, n-butyl group, i-butyl group, sec-butyl group, tert-butyl group, isopentyl group, t-pentyl group, neopentyl group, isohexyl group, aralkyl group having 7 to 8 carbon atoms (benzyl group, Phenethyl group), phenyl group, alkoxy group, cyclohexyl group, biphenyl group, naphthyl group or heterocyclic group (pyridyl group, carbazolyl group, quinolyl group, etc.). In addition, R ^{1 to} R ⁴ may have a substituent bonded to them. That is, R ^{1 to} R ⁴ are each a substituent-containing phenyl group, a substituent-containing aralkyl group, a substituent-containing cyclohexyl group, a substituent-containing biphenyl group, a substituent-containing naphthyl group or a substituent-containing heterocyclic group. . Here, the substituent is an alkyl group, an alkoxy group, an aryloxy group, a phenyl group, a nitro group, a hydroxyl group, or a halogen, and a plurality of substituents may be substituted. Therefore, the substituent-containing aralkyl group is an alkyl group-substituted aralkyl group (methylbenzyl group, methylphenethyl group, etc.),
Alkoxy group-substituted aralkyl group (methoxybenzyl group,
Ethoxyphenethyl group, etc.), aryloxy group-substituted aralkyl group (phenoxybenzyl group, naphthyloxyphenethyl group, etc.), phenyl group-substituted aralkyl group (phenylphenethyl group, etc.) The above-mentioned substituent-containing phenyl group is an alkyl group-substituted phenyl group (tolyl group). Group, dimethylphenyl group,
Ethylphenyl group, etc., alkoxy group-substituted phenyl group (methoxyphenyl group, ethoxyphenyl group, etc.) aryloxy group-substituted phenyl group (phenoxyphenyl group,
A naphthyloxyphenyl group or the like) or a phenyl group-substituted phenyl group (that is, a biphenylyl group). Also,
The substituent-containing cyclohexyl group includes an alkyl group-substituted cyclohexyl group (methylcyclohexyl group, dimethylcyclohexyl group, ethylcyclohexyl group, etc.), an alkoxy group-substituted cyclohexyl group (methoxycyclohexyl group,
Ethoxycyclohexyl group) or aryloxy group-substituted cyclohexyl group (phenoxycyclohexyl group, naphthyloxycyclohexyl group), phenyl group-substituted cyclohexyl group (phenylcyclohexyl group). The substituent-containing naphthyl group includes an alkyl group-substituted naphthyl group (methylnaphthyl group, dimethylnaphthyl group, etc.), an alkoxy group-substituted naphthyl group (methoxynaphthyl group, ethoxynaphthyl group, etc.) or an aryloxy group-substituted naphthyl group (phenoxynaphthyl group, Naphthyloxynaphthyl group) and a phenyl group-substituted naphthyl group. Further, as examples of the substituent-containing heterocyclic group, for example, the substituent-containing pyridyl group includes an alkyl group-substituted pyridyl group (methylpyridyl group, dimethylpyridyl group, ethylpyridyl group, etc.), an alkoxy group-substituted pyridyl group (methoxypyridyl group). , Ethoxypyridyl group) or aryloxy group-substituted pyridyl group (phenoxypyridyl group, naphthyloxypyridyl group), phenyl group-substituted pyridyl group.

Of the above-mentioned ones, R ^{1 to} R ⁴ are preferably an alkyl group having 1 to 6 carbon atoms, an aryloxy group, a phenyl group, a naphthyl group, a biphenyl group, a pyridyl group and a cyclohexyl group. These may be substituted or unsubstituted.

On the other hand, Ar in the general formula (I) is a substituted or unsubstituted arylene group such as a phenylene group, a biphenylene group, a p-terphenylene group, a naphthylene group, and an anthracenediyl group. May be.
Further, the bonding position of methylidin C = CH- may be any position such as ortho, meta and para. However, when Ar is an unsubstituted phenylene, R ^{1 to} R ⁴ have 1 to 1 carbon atoms.
It is selected from an alkoxy group having 6 carbon atoms, an aralkyl group having 7 to 8 carbon atoms, a substituted or unsubstituted naphthyl group, a biphenyl group, a cyclohexyl group, a pyridyl group and an aryloxy group. The substituent is an alkyl group (methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, isopentyl group, t-
Pentyl group, neopentyl group, isohexyl group, etc., alkoxy group (methoxy group, ethoxy group, propoxy group, i
-Propoxy group, butyloxy group, i-butyloxy group, s
ec-Butyloxy group, t-butyloxy group, isopentyloxy group, t-pentyloxy group), aryloxy group (phenoxy group, naphthyloxy group, etc.) Phenyl group, hydroxyl group, nitro group, halogen, even single substitution Multiple substitutions may be made.

The dimethylidyne aromatic compound represented by the formula (I) has two methylidyne (C = CH-) units in one molecule, and by the geometrical isomerism of the methylidyne units,
There are four combinations, that is, cis-cis, trans-cis, cis-trans and trans-trans combinations, and the dimethylidyne aromatic compound of the present invention may be any of them. It may be a mixture of geometric isomers. Particularly preferably, all are trans.

Specific examples of the compound represented by the general formula (I) include:
The following can be mentioned.

The aromatic dimethylidyne compound of the present invention thus obtained can be effectively used as an EL device capable of emitting light with high brightness at low voltage. The aromatic dimethylidyne compound of the present invention has the electron injection function, the electron transport function and the light emitting function which are indispensable as the light emitting layer of the EL device, and is excellent in heat resistance and thin film property. Furthermore, this aromatic dimethylidene compound, even if heated to the vapor deposition temperature,
There is an advantage that a dense film composed of uniform fine crystal grains can be formed without being decomposed or altered, and pinholes are not generated.

As described above, the compound represented by the general formula (I) of the present invention is effective as a light emitting layer in an EL device. This light emitting layer may be formed, for example, by vapor deposition, spin coating,
The compound of general formula (I) can be formed into a thin film by a known method such as a casting method, but a molecular deposition film is particularly preferable. Here, the molecular deposition film is a thin film formed by depositing the compound from a gas phase state, or a film formed by solidifying from a solution state or a liquid phase state of the compound, for example, a vapor deposition film or the like. Although shown, this molecular deposition film can be generally distinguished from a thin film (molecular cumulative film) formed by the LB method. Further, the light emitting layer, as disclosed in JP-A-59-194393, etc., a binder such as a resin and the compound are dissolved in a solvent to form a solution, which is then spin coated. It can be formed into a thin film by a method or the like.

The thin film of the light emitting layer thus formed is not particularly limited and can be appropriately selected depending on the situation.
Usually, it is selected in the range of 5 nm to 5 μm.

The light emitting layer of this EL element is (1) when an electric field is applied,
Holes can be injected by the anode or the hole injection layer,
In addition, an injection function capable of injecting electrons from the cathode or the electron injection layer, (2) a transport function for moving the injected charges (electrons and holes) by the force of the electric field, (3) recombination of electrons and holes It provides a field inside the light emitting layer and has a light emitting function of connecting this to light emission.

It should be noted that there may be a difference between the ease with which holes are injected and the ease with which electrons are injected, and the transport capacity represented by the mobility of holes and electrons may be large or small. It is preferable to transfer charges.

Since the compound represented by the general formula (I) used for the light emitting layer generally has an ionization energy of less than about 6.0 eV, it is relatively easy to inject holes by selecting an appropriate anode metal or anode compound. Further, since the electron affinity is larger than about 2.8 eV, if an appropriate cathode metal or cathode compound is selected, it is relatively easy to inject electrons and the electron and hole transporting ability is excellent. Furthermore, since the solid-state fluorescence is strong,
It has a large ability to convert the excited state formed at the time of recrystallization of electrons and holes of the compound or its associated body or crystal into light.

The EL device using the compound of the present invention may have various modes. Basically, the light emitting layer is sandwiched between a pair of electrodes (anode and cathode), and if necessary. Then, the hole injection layer and the electron injection layer may be interposed. Specifically, (1) anode / light emitting layer / cathode, (2) anode / hole injection layer / light emitting layer / cathode, (3) anode / hole injection layer / light emitting layer / electron injection layer / cathode, etc. Can be mentioned.
The hole injection layer and the electron injection layer are not always necessary, but the presence of these layers further improves the light emission performance.

Further, it is preferable that all of the elements having the above-mentioned constitution are supported by a substrate, and the substrate is not particularly limited, and is made of one conventionally used for EL elements, for example, glass, transparent plastic, quartz or the like. Any thing can be used.

As the anode in this EL element, a material having an electrode substance of a metal, an alloy, an electrically conductive compound having a large work function (4 eV or more) and a mixture thereof is preferably used.
Specific examples of such electrode materials include metals such as Au and Cu.
Dielectric transparent materials such as I, ITO, SnO ₂ and ZnO are mentioned. The anode can be prepared by forming a thin film of these electrode substances by a method such as vapor deposition or sputtering. When the emitted light is taken out from this electrode, it is desirable that the transmittance is higher than 10%, and the sheet resistance as the electrode is preferably several hundred Ω / mm or less.

Furthermore, the film thickness depends on the material, but is usually 10 nm to 1 μm,
It is preferably selected in the range of 10 to 200 nm.

On the other hand, the cathode has a low work function (4 eV or less)
A material that uses a metal, an alloy, an electrically conductive compound, or a mixture thereof as an electrode material is used. Specific examples of such an electrode material include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, Al / AlO ₂ , indium and the like. The cathode is
These electrode materials can be produced by forming a thin film by a method such as vapor deposition or sputtering. The sheet resistance as an electrode is preferably several hundred Ω / mm or less, and the film thickness is usually 10 nm to 1 μm, preferably 50
Selected in the range of ~ 200 nm. In this EL element, it is convenient that either the anode or the cathode is transparent or semi-transparent to allow the emitted light to pass therethrough, so that the emission efficiency of the emitted light is good.

The EL device using the compound of the present invention has various modes as described above, and the hole injecting layer (hole injecting and transporting layer) in the EL device of the above (2) or (3) is A layer made of a hole-transporting compound, which has a function of transmitting holes injected from the anode to the light-emitting layer, and the hole-injecting layer is interposed between the anode and the light-emitting layer to lower the layer. Many holes are injected into the light emitting layer by the electric field, and the electrons injected from the cathode or the electron injection layer into the light emitting layer are emitted by the barrier of electrons existing at the interface between the light emitting layer and the hole injection layer. Accumulation near the interface in the layer improves luminous efficiency,
The device has excellent light emitting performance.

The hole transport compound used in the hole injection layer may be disposed between two electrodes to which an electric field is applied and, when holes are injected from the anode, may appropriately transfer the holes to the light emitting layer. A compound having a hole mobility of at least 10 ⁻⁶ cm ² / V · sec when an electric field of 10 ⁴ to 10 ⁶ V / cm is applied is preferable.

The hole transporting compound is not particularly limited as long as it has the above-mentioned preferable properties, and is conventionally used as a charge transporting material for holes in photoconductive materials and hole of EL elements. Any known material used for the injection layer can be selected and used.

Examples of the charge transport material include triazole derivatives (such as those described in US Pat. No. 3,112,197),
Oxadiazole dielectrics (described in US Pat. No. 3,189,447), imidazole derivatives (Japanese Patent Publication No.
-16096) and polyarylalkane derivatives (US Pat. Nos. 3,615,402 and 3,820,9).
89, 3,542,544, JP-B-45-555, JP-A-51-10983, JP-A-51-93224, JP-A-51-93224
-17105, 56-4148, 55-108667, 55-156953, 56-36656, etc.) Pyrazoline derivatives and pyrazolone derivatives (US Pat. No. 3,180,729) No. 4,278,746, JP-A-55-88064, JP-A-55-88065, and JP-A-49-1055.
37, 55-51086, 56-80051, and
56-88141, 57-45545, 54-112637, 55-74546, etc.), phenylenediamine derivatives (US Pat. No. 3,615,404,
JP-B-51-10105, JP-A-46-3712, JP-A-47-253
36, JP-A-54-53435, JP-A-54-110536, JP-A-54-119925, etc.), arylamine derivatives (US Pat. Nos. 3,567,450, 3,18).
No. 0,703, No. 3,240,597, No. 3,658,520, No. 4,232,103, No. 4,175,961
No. 4,012,376, Japanese Patent Publication No. 49-35702, No. 39-
27577, JP-A-55-144250, JP-A-56-119132
No. 56-22437, West German Patent No. 1,110,518, etc.), amino-substituted chalcone derivatives (US Patent No. 3,526,501, etc.),
Oxazole derivatives (described in US Pat. No. 3,257,203, etc.), styrylanthracene derivatives (described in JP-A-56-46234, etc.), fluorenone derivatives (described in JP-A-54-110837, etc.) Stuff),
Hydrazone derivatives (U.S. Pat. No. 3,717,462, JP-A-54-59143, JP-A-55-52063, JP-A-55-5206)
4, gazette 55-46760 gazette, gazette 55-85495 gazette, gazette 5
7-11350, 57-148749, etc.), stilber derivatives (JP-A 61-210363, 61-228451, 61-14642, 61-61). 7
2255, 62-47646, 62-36674,
62-10652, 62-30255, 60-93445.
Gazette, gazette 60-94462 gazette, gazette 60-174749 gazette, gazette 6
Those described in JP-A No. 0-175052) and the like.

These compounds can be used as a hole transfer compound, and the following porphyrin compounds (Japanese Patent Laid-Open No. 63-
295695) and aromatic tertiary amine compounds and styrylamine compounds (US Pat. No. 4,127,
412, JP-A-53-27033, JP-A-54-58445, JP-A-54-149634, JP-A-54-64299, and JP-A-55.
-79450, 55-144250, 56-119132, 61-295558, 61-98353, 63
-295695) and particularly the aromatic tertiary amine compound is preferably used.

Typical examples of the porphyrin compound include porphyrin; 1,10,15,20-tetraphenyl-21H, 23H-porphyrin copper (II); 1,10,15,20-tetraphenyl-21H, 23H-porphyrin zinc ( II); 5,10,15,20-tetrakis (pentafluorophenyl) -21H, 23H-porphyrin; silicon phthalocyanine oxide; aluminum phthalocyanine chloride; phthalocyanine (metal-free); dilithium phthalocyanine; copper tetramethylphthalocyanine; copper phthalocyanine; Examples include chromium phthalocyanine; zinc phthalocyanine; lead phthalocyanine; titanium phthalocyanine oxide; magnesium phthalocyanine; copper octamethylphthalocyanine. Further, as typical examples of the aromatic tertiary compound and the styrylamine compound, N,
N, N ', N'-tetraphenyl-4,4'-diaminobiphenyl; N, N'-diphenyl-N, N'-di (3-methylphenyl) -4,4'-diaminobiphenyl; 2,2 -Bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4
-Di-p-tolylaminophenyl) cyclohexane; N,
N, N ', N'-tetra-p-tolyl-4,4'-diaminobiphenyl; 1,1-bis (4-di-p-tolylaminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino 2-Methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N'-di (4-methoxyphenyl) -4,4'-diamino Biphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,
4'-bis (diphenylamino) quadriphenyl; N,
N, N-tri (p-tolyl) amine; 4- (di-p-tolylamine) -4 '-[4 (di-p-tolylamine) styryl] stilbene; 4-N, N-diphenylamino- (2- Diphenylvinyl) benzene; 3-methoxy-4'-N, N-
Diphenylaminostilbene; N-phenylcarbazole and the like can be mentioned.

The hole injection layer in the EL device may be composed of a single layer composed of one or more of these hole transport compounds, or a hole injection layer composed of a compound different from the above layer is laminated. It may be one.

On the other hand, the electron injecting layer (electron injecting and transporting layer) in the EL device having the above-mentioned constitution (3) is made of an electron transfer compound and has a function of transferring the electrons injected from the cathode to the light emitting layer. There is. There is no particular limitation on such an electron transfer compound, and any compound can be selected and used from conventionally known compounds. Preferred examples of the electron transfer compound include: Nitro-substituted fluorenone derivatives, such as Thiopyran dioxide derivatives such as And other diphenylquinoline derivatives [as described in "Polymer Preprints, Japan", Volume 37, No. 3, page 681 (1988), or the like, or And other compounds [Journal of Applied Physics, Vol. 27, 269 (1988)
, Etc.] and anthraquinodimethane derivatives (JP-A-57-149259, JP-A-58-55450, JP-A-58-55450).
No. 1-225151, No. 61-233750, No. 68-104061
JP-A-60-69657, JP-A-61-143764, and fluorenylidene methane derivatives.
61-148159) and anthrone derivatives (described in JP-A-61-225151 and 61-233750).

Next, an example of a suitable method for producing an EL device using the compound of the present invention will be described for each device of each constitution. Explaining the manufacturing method of the EL element consisting of the above-mentioned anode / light-emitting layer / cathode, first, on a suitable substrate, a thin film of a desired electrode substance, for example, a substance for anode, 1 μm or less,
After forming an anode by forming it by a method such as vapor deposition or sputtering so that the film thickness is preferably in the range of 10 to 200 nm, a thin film of a compound represented by the general formula (I) which is a light emitting material is formed thereon. And a light emitting layer is provided. As a method for thinning the light emitting material, there are, for example, a spin coating method, a casting method, a vapor deposition method and the like, but the vapor deposition method is preferable from the viewpoint that a uniform film is easily obtained and pinholes are not easily generated. .

When this vapor deposition method is used for thinning the light emitting material,
The deposition conditions, the type of organic compound used in the light emitting layer to be used, the crystal structure of interest of the molecular deposit film, varies depending on such association structures, generally boat temperature 50 to 400 ° C., vacuum degree of 10 ^-5 to 10 ^{- 3} Pa, evaporation temperature 0.01 to 50 nm / sec, substrate temperature −
It is desirable to select appropriately within the range of 50 to + 300 ° C. and the film thickness of 5 nm to 5 μm. Next, after forming this light emitting layer, a thin film made of a material for the cathode is formed thereon with a thickness of 1 μm or less, preferably 50 to 20.
A desired EL element can be obtained by forming a film having a thickness of 0 nm by, for example, vapor deposition or sputtering and providing a cathode. In the production of this EL element, it is also possible to reverse the production order and produce the cathode, the light emitting layer and the anode in this order.

Next, a method of manufacturing an EL element composed of anode / hole injection layer / light emitting layer / cathode will be described.
After forming it in the same manner as in the case of the device, a thin film made of a hole transfer compound is formed thereon by a vapor deposition method or the like to provide a hole injection layer. The vapor deposition conditions at this time may conform to the vapor deposition conditions for forming the thin film of the light emitting material. Next, a desired EL element is obtained by sequentially providing a light emitting layer and a cathode on the hole injecting layer in the same manner as in the case of manufacturing the EL element.

Also in the production of this EL element, the production order can be reversed to produce the cathode, the light emitting layer, the hole injection layer, and the anode in this order.

Furthermore, a method of manufacturing an EL element composed of anode / hole injection layer / light emitting layer / electron injection layer / cathode will be described.
Similarly to the case of manufacturing the EL device, an anode, a hole injection layer, and a light emitting layer are sequentially provided, and then a thin film made of an electron transfer compound is formed on the light emitting layer by a vapor deposition method or the like.
An electron injection layer is provided, and then a cathode is provided thereon in the same manner as in the case of manufacturing the EL element to obtain a desired EL.
The device is obtained. In addition, also in the production of this EL element,
The order of fabrication may be reversed, and the cathode, the electron injection layer, the light emitting layer, the hole injection layer, and the anode may be fabricated in this order.

When a direct current voltage is applied to the EL element obtained in this manner, the positive electrode has a positive polarity and the negative electrode has a negative polarity.
When a voltage of about 40 V is applied, light emission can be observed from the transparent or semitransparent electrode side. Moreover, even if a voltage is applied with the opposite polarity, no current flows and no light emission occurs. Further, when an AC voltage is applied, light is emitted only when the anode is in the + state and the cathode is in the − state. The waveform of the alternating current applied may be arbitrary.

Next, the light emitting mechanism of the EL device will be described by taking the case of the structure of anode / hole injecting / transporting layer / light emitting layer / cathode as an example. When a voltage is applied with the positive polarity of the anode and the negative polarity of the cathode, electric field is injected from the anode into the hole injection layer. The injected holes are transported inside the hole injecting and transporting layer toward the interface with the light emitting layer, and are injected or transported from the interface to a region where the light emitting function is exhibited (for example, the light emitting layer).

On the other hand, the electrons are injected from the cathode into the light emitting layer by an electric field, further transported, and recombined with the holes in the region where the holes are present, that is, the region where the light emitting function is exhibited (in this sense, the region is It may be called a recombination region). When this recombination occurs, an excited state of a molecule, its associated body, a crystal, or the like is formed, and this is converted into light. The recombination region may be the interface between the hole injecting and transporting layer and the light emitting layer,
It may be the interface between the light emitting layer and the cathode, or may be the central portion of the light emitting layer that is separated from both interfaces. This depends on the type of compound used, its association and crystal structure.

〔Example〕

Next, the present invention will be described in more detail based on examples and application examples.

Example 1 (1) Production of phosphorus compound containing arylene group 25 g of 2,5-bis (chloromethyl) xylene and 45 g of triethyl phosphite were placed in an oil bath under an argon stream at a temperature of 150.
The mixture was heated and stirred at 7 ° C for 7 hours.

Then, excess triethyl phosphite and by-produced ethyl chloride were distilled off under reduced pressure. After standing overnight, 50 g (quantitative) of white crystals were obtained. The melting point of this product was 59.0 to 60.5 ° C. The ¹ H-NMR analysis is as follows. ¹ H-NMR (CDCl ₃ ) δ = 6.9 ppm (s; 2H, central xylene ring-H) δ = 3.9 ppm (q; 8H, ethoxy group methylene-CH ₂ ) δ = 3.1 ppm (d; 4H, J = 20Hz ( ³¹ P- ¹ H coupling) P
-CH ₂ ) δ = 2.2 ppm (s; 6H, xylene ring -CH ₃ ) δ = 1.1 ppm (t; 12H, ethoxy group methyl -CH ₃ ) From the above results, the above product is represented by the following formula. It was confirmed that this is a phosphorus compound containing an arylene group (phosphonate).

(2) Production of aromatic dimethylidene compound 5.3 g of phosphonate obtained in (1) above and 5.2 g of 2-benzoylbiphenyl are dissolved in 100 ml of tetrahydrofuran, and hexane containing n-butyllithium (concentration 15%) Add 12.3 g of the solution and add 6 at room temperature under an argon stream.
After stirring for an hour, it was left overnight.

300 ml of methanol was added to the obtained mixture, and the precipitated crystals were filtered. The filtered product is then triturated with 100 ml of water.
After thorough washing with 100 ml of methanol three times, 5.5 g of pale yellow powder was obtained (yield 44%). The melting point of this product is 187.
It was ~ 188 ° C. The ¹ H-NMR analysis of this powder is as follows. ¹ H-NMR (CDCl ₃ ) δ = 7.7 to 7.0 ppm (m; 30H, aromatic ring) δ = 6.7 ppm (s; 2H, methylidin CH═C−) δ = 2.0 ppm (s; 6H, xylene ring-CH) ₃ ) Furthermore, the elemental analysis results are as follows with composition formula C ₄₈ H ₃₈ . The values in parentheses are theoretical values.

C: 93.79% (93.82%) H: 6.06% (6.18%) N: 0.00% (0%) Also, infrared (IR) absorption spectrum (KBr tablet method)
Is as follows.

Since ν _cc 1520,1620 cm ^-1 or more, the above product pale yellow powder is It was confirmed to be a 2,5-xylene dimethylidene derivative represented by

Examples 2 to 7 Example 1 (2) was repeated except that the ketone shown in Table 1 was used instead of 2-benzoylbiphenyl.
The same operation as in (2) was performed to obtain the 2,5-xylenedimethylidene derivative shown in Table 1.

Example 8 (Method B) (1) Production of phosphorus compound (1-Bromoethyl) benzene (25.1 g) and triethyl phosphite (24.7 g) were heated at a temperature of 150 in an oil bath under an argon stream.
The mixture was heated and stirred at 7 ° C for 7 hours. Thereafter, excess triethyl phosphite and by-produced bromoethyl were distilled off under reduced pressure,
22.3 g of a clear solution was obtained. The ¹ H-NMR analysis result of this product is
It is as follows.

δ = 7.2 ppm (s; 5H, benzene ring-H) δ = 3.9 ppm (q; 4H, ethoxy group-OCH ₂ —) δ = 2.9 to 3.5 ppm (m; 1H, = CH−) δ = 1.0 to 2.0 ppm; than that of the (m 9H, methyl and -CH ₃ ethoxy) above, the product was confirmed to be a containing phosphorus compound represented by the following formula (phosphonate).

(2) Production of aromatic dimethylidene compound 9.7 g of the phosphonate obtained in (1) above and 3.0 g of 2,5-xylenedicarboxaldehyde were dissolved in 100 ml of tetrahydrofuran, and n-putyllithium (concentration 15
u) in hexane solution (3.0 g) was added,
After stirring at room temperature for 5 hours, it was left overnight.

100 ml of methanol was added to the obtained mixture, and the precipitated crystals were filtered. The filtered product was thoroughly washed 3 times with 100 ml of water and then 3 times with 100 ml of methanol to give white scale crystals 1.3.
g was obtained (20% yield).

The melting point of this product was 137.0 to 137.8 ° C. The ¹ H-NMR analysis of this crystal is as follows. ¹ H-NMR (CDCl ₃ ) δ = 7.2 to 7.5 ppm (m; 12H, benzene ring-H, central xylene ring-H) δ = 6.8 ppm (s; 2H, methylidin CH = C-) δ = 2.3 ppm ( s; 6H, methyl group) δ = 2.1ppm (s; 6H , central xylene ring -CH ₃₎ further the elemental analysis results are as follows as the composition formula C ₂₆ H _26. The values in parentheses are theoretical values.

C: 92.26% (92.31%) H: 7.50% (7.69%) N: 0.00% (0%) Further, the molecular ion peak m / Z = 318 of the target substance was detected from the mass spectrum.

From the above, the white scaly crystals that are the above product,
The following formula It was confirmed to be a 2,5-xylene dimethylidene derivative represented by

Example 9 (1) Production of phosphorus compound containing arylene group 9.0 g of 4,4′-bis (bromomethyl) biphenyl and 11 g of triethyl phosphite were placed in an oil bath under an argon stream in an oil bath.
The mixture was heated and stirred at a temperature of 140 ° C. for 6 hours.

Then, excess triethyl phosphite and by-produced ethyl chloride were distilled off under reduced pressure. After standing overnight, white crystals (9.5 g, yield 80%) were obtained. The melting point of this product was 97.0 to 100.0 ° C. The ¹ H-NMR analysis is as follows. ¹ H-NMR (CDCl ₃ ) δ = 7.0 to 7.6 ppm (m; 8H, biphenylene ring-H) δ = 4.0 ppm (q; 8H, ethoxy group methylene-CH ₂ ) δ = 3.1 ppm (d; 4H, J = 20Hz ( ³¹ P- ¹ H coupling) P
-CH ₂ ) δ = 1.3 ppm (t; 12H, ethoxy group methyl-CH ₃ ) From the above results, it was confirmed that the above-mentioned product was an arylene group-containing phosphorus compound (phosphonate) represented by the following formula. It was

(2) Production of aromatic dimethylidene compound 4.0 g of phosphonate and 5.0 g of cyclohexyl phenyl ketone obtained in (1) above are dissolved in 60 ml of dimethysulfoxide, 2.0 g of potassium-t-butoxide is added, and the mixture is refluxed under an argon stream. After stirring, it was left overnight.

After distilling off the solvent of the obtained mixture, methanol 200 m
l was added and the precipitated crystals were filtered. Then, the filtered product was thoroughly washed with 100 ml of water three times and then with 100 ml of methanol three times, and recrystallized from benzene to give a pale yellow powder.
1.0 g was obtained (yield 22%). The melting point of this product is 153-1
55 ° C. The results of ¹ H-NMR analysis of this powder are as follows. ¹ H-NMR (CDCl ₃ ) δ = 6.3-7.5 ppm (b; 18H, aromatic and methylidin CH
= C−) δ = 1.0 to 2.0 ppm (b; 22H, cyclohexane ring) Further, the elemental analysis result is as follows as a composition formula C ₄₀ H ₄₂ . The values in parentheses are theoretical values.

C: 91.74% (91.90%) H: 8.25% (8.10%) N: 0.00% (0%) Also, infrared (IR) absorption spectrum (KBr tablet method)
Is as follows.

ν _cc 1520,1610 cm ^{-1 In} addition, the molecular ion peak m / Z = 522 of the target substance was detected from the mass spectrum.

From the above, the light yellow powder which is the above product has the following formula: It was confirmed to be a 4,4'-biphenylene dimethylidene derivative represented by

Example 10 The same operation as in Example 9 (2) except that 4,4′-dimethylbenzophenone was used in place of cyclohexylphenylketone and tetrahydrofuran was used in place of dimethylsulfoxide in Example 9 (2). hand,
The 4,4'-biphenylene dimethylidene derivative shown below was obtained.

The analysis results of this product are as follows.

Melting point: 228 to 230 ° C ¹ H-NMR (CDCl ₃ ) δ = 6.7 to 7.3 ppm (m; 26H, aromatic ring -H and methylidin
CH = C-) δ = 2.4ppm ( s: 12H, p- tolylmethyl group -CH ₃₎ Property: pale yellow powder mass spectrum having a molecular ion peak: m / Z = 566 Elementary analysis: as the composition formula C ₄₄ H ₃₈ It is as follows. The values in parentheses are theoretical values.

C: 93.10% (93.24%) H: 7.04% (6.76%) N: 0.00% (0%) Example 11 (1) Production of arylene group-containing phosphorus compound 2,6-bis (bromomethyl) naphthalene 24.3 g 50 g of triethyl phosphate was heated and stirred in an oil bath at a temperature of 120 ° C. for 7 hours under an argon stream.

Then, excess triethyl phosphite and by-produced ethyl chloride were distilled off under reduced pressure. After standing overnight, pale yellow crystals 32.5g
(Quantitative yield) was obtained. The melting point of this product is 144.5-146.0
° C. The results of ¹ H-NMR analysis are as follows. ¹ H-NMR (CDCl ₃ ) δ = 7.2 to 7.8 ppm (m; 6H, naphthylene ring-H) δ = 4.0 ppm (q; 8H, ethoxy group methylene-CH ₂ ) δ = 3.3 ppm (d; 4H, J = 20Hz ( ³¹ P- ¹ H coupling) P
_{-CH 2) δ = 1.2ppm (t} ; from 12H, methylene ethoxy -CH ₃₎ As a result, the product described above, it is confirmed that an arylene group containing phosphorus compound represented by the following formula (phosphonate) It was

(2) Production of aromatic dimethylidene compound 5.0 g of the phosphonate obtained in (1) above and 5.0 g of cyclohexyl phenyl ketone were added to 100 ml of tetrahydrofuran.
Dissolved in, 2.5 g of potassium-t-butoxide was added, and the mixture was stirred under reflux under an argon stream, and then left overnight.

After distilling off the solvent of the obtained mixture, methanol 100 m
l was added and the precipitated crystals were filtered. Then, the filtered product was thoroughly washed twice with 100 ml of water and then twice with 100 ml of methanol, and recrystallized from benzene to obtain 1.0 g of a pale yellow powder.
Was obtained (yield 20%). The melting point of this product is 215-216 ℃
Met. The results of ¹ H-NMR analysis of this powder are as follows. ¹ H-NMR (CDCl ₃ ) δ = 6.2 to 7.2 ppm (m; 18H, aromatic ring and naphthalene ring-H
And methylidin CH = C-) δ = 1.0 to 2.0 ppm (b; 22H, cyclohexane ring) Further, the elemental analysis result is as follows as the composition formula C ₃₈ H ₄₀ . The values in parentheses are theoretical values.

C: 91.63% (91.88%) H: 8.20% (8.12%) N: 0.00% (0%) From the above, the light yellow powder which is the above product has the following formula: It was confirmed that the derivative was a 2,6-naphthylene dimethylidene derivative represented by

Example 12 Example 11 (2) was repeated except that 4,4′-dimethylbenzophenone was used in place of cyclohexylphenyl ketone and n-butyllithium was used in place of potassium-t-butoxide in Example 11 (2). ) Was carried out in the same manner as described above to obtain a 2,6-naphthylenedimethylidene derivative shown below.

The analysis results of this product are as follows.

Melting point: 269 to 271 ° C ¹ H-NMR (CDCl ₃ ) δ = 6.7 to 7.2 ppm (m; 24H, aromatic ring -H and methylidin
CH = C-) δ = 2.4ppm ( s; 12H, p- tolylmethyl group -CH ₃₎ Property: yellow powder Elemental analysis value: as follows as the composition formula C ₄₂ H _36.
The values in parentheses are theoretical values.

C: 93.03% (93.29%) H: 6.81% (6.71%) N: 0.00% (0%) Example 13 (1) Production of arylene group-containing phosphorus compound 9,10-bis (chloromethyl) anthracene 10 g 35 g of triethyl phosphate in an oil bath under argon flow,
The mixture was heated and stirred at a temperature of 130 ° C. for 6 hours.

Then, excess triethyl phosphite and by-produced ethyl chloride were distilled off under reduced pressure. After standing overnight, the obtained light green crystals were recrystallized from benzene-hexane to obtain 16 g of pale yellow scaly crystals (yield 92%).

 The analysis results of this product are as follows.

Melting point: 160 to 161.5 ° C. ¹ H-NMR (CDCl ₃ ) δ = 7.3 to 8.4 ppm (m; 8H, acetracene ring-H) δ = 4.1 ppm (d; 4H, J = 20 Hz ( ³¹ P- ¹ H coupling ) P
-CH ₂ ) δ = 3.7 ppm (q; 8H, ethoxy group methylene-CH ₂ ) δ = 1.0 ppm (t; 12H, ethoxy group methyl-CH ₃ ) From the above results, the above product is represented by the following formula: It was confirmed to be the represented arylene group-containing phosphorus compound (phosphonate).

(2) Production of aromatic dimethylidene compound 3.0 g of the phosphonate obtained in (1) above and 2.5 g of 4,4'-dimethylbenzophenone were added to 100 m of tetrahydrofuran.
5 g of hexane solution containing n-butyllithium (concentration 15%) was added to the solution, and the mixture was stirred at room temperature under argon flow for 4 hours.
After stirring for an hour, it was left overnight.

100 ml of methanol was added to the obtained mixture, and the precipitated crystals were filtered. The filtered product was thoroughly washed 3 times with 100 ml of water and then 3 times with 100 ml of methanol, and recrystallized from toluene to obtain 0.7 g of a yellow-orange powder (yield 19%).

 The analysis results of this product are as follows.

Melting point: 297 to 298 ° C ¹ H-NMR (CDCl ₃ ) δ = 6.5 to 7.5 ppm (m; 26H, aromatic ring-H, acetracene-H
And methylidin CH = C-) δ = 2.2 ppm (d; 12H, p-tolylmethyl group-CH ₃ ) Elemental analysis value: The composition formula is as follows: C ₄₆ H ₃₈ . The values in parentheses are theoretical values.

C: 93.42% (93.52%) H: 6.53% (6.48%) N: 0.00% (0%) In addition, the molecular ion peak of the target substance from the mass spectrum
m / Z = 590 was detected.

From the above, the yellow-orange powder which is the above product has the following formula: It was confirmed that the derivative was a 9,10-acetracenediyl dimethylidin derivative represented by

Examples 14 to 26 The compounds shown in Table 2 were synthesized using the corresponding ketones and phosphonates.

Application example 1 ITO is vapor-deposited on a glass substrate of 25 mm x 75 mm x 1.1 mm.
The transparent support substrate was a film (made by HOYA) having a thickness of 100 nm.

This transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Nippon Vacuum Technology Co., Ltd.), 200 mg of TPDA was put in a resistance heating boat made of molybdenum, and another molybdenum boat was obtained in Example 1. Further, 200 mg of 2,5-bis (2-phenyl-2-biphenylvinyl) xylene (BPVX), which is a 2,5-xylene dimethylidylidine derivative, was put in the vacuum chamber and the pressure in the vacuum chamber was reduced to 1 × 10 ^-4 Pa.

Then, the boat containing TPDA was heated to 215 to 220 ° C., and TPDA was vapor-deposited on the transparent support substrate at a vapor deposition rate of 0.1 to 0.3 nm / sec to form a hole injection layer having a film thickness of 60 nm. The substrate temperature at this time was room temperature.

Next, without removing this from the vacuum chamber, BPVX was used as a light emitting layer on the hole injection layer from another boat.
80 nm laminated vapor deposition was performed. As for the vapor deposition conditions, the boat temperature was 184 ℃, the vapor deposition rate was 0.2 to 0.4 nm / sec, and the substrate temperature was room temperature.

This was taken out of the vacuum chamber, a stainless steel mask was placed on the light emitting layer, and it was fixed again to the substrate holder.

Next, 1 g of magnesium ribbon was put in a resistance heating boat made of molybden, and 500 mg of indium was attached to another resistance heating boat made of molybden.

After that, the pressure in the vacuum chamber was reduced to 2 × 10 ^-4 Pa, and then indium was vapor-deposited at a rate of 0.03 to 0.08 nm / sec and, at the same time, magnesium was vapor-deposited from the other boat at a rate of 1.7 to 2.8 nm / sec. It was The boat temperature was about 800 ℃ and 500 ℃ for indium and magnesium, respectively. Under the above conditions, a mixed metal electrode of magnesium and indium was laminated and vapor-deposited on the light emitting layer in a thickness of 150 nm to form a counter electrode, thereby forming an element.

When a DC voltage of 20 V is applied to the obtained device with the ITO electrode as the anode and the mixed metal electrode of magnesium and indium as the cathode, a current of about 170 mA / cm ² flows, and the blue coordinates in the chromaticity coordinate
h Green luminescence was obtained. The peak wavelength was 499 nm by spectroscopic measurement, and the emission luminance was 1000 cd / m ² or more.

Application example 2 ITO is vapor-deposited on a glass substrate of 25 mm × 75 mm × 1.1 mm.
The transparent support substrate was a film (made by HOYA) having a thickness of 100 nm.

This transparent support substrate was washed with UV ozone for 2 minutes using a UV ozone treatment device (manufactured by Nippon Battery Co., Ltd.).

Then, it was fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Nippon Vacuum Technology Co., Ltd.), 200 mg of TPDA was put into a resistance heating boat made of molybdenum, and another molybdenum boat was obtained in Example 2, 2. 200 mg of 2,5-bis (2,2-di-p-trivinyl) xylene (DTVX), which is a 5-xylene dimethylidyne derivative, was put in the vacuum chamber and the pressure in the vacuum chamber was reduced to 1 × 10 ⁻⁴ Pa.

Then, the boat containing TPDA was heated to 215 to 220 ° C., and TPDA was vapor-deposited on the transparent support substrate at a vapor deposition rate of 0.1 to 0.3 nm / sec to form a hole injection layer having a film thickness of 60 nm. The substrate temperature at this time was room temperature.

Next, without removing this from the vacuum chamber, DTVX was used as the light emitting layer from another boat on the hole injection layer.
80 nm laminated vapor deposition was performed. Deposition conditions are boat temperature of 215 ° C.
The deposition rate was 0.2 to 0.4 nm / sec, and the substrate temperature was room temperature.

This was taken out of the vacuum chamber, a stainless steel mask was placed on the light emitting layer, and it was fixed again to the substrate holder.

Next, 1 g of magnesium ribbon was put in a resistance heating boat made of molybden, and 500 mg of indium was attached to another resistance heating boat made of molybden.

After that, the pressure in the vacuum chamber was reduced to 2 × 10 ^-4 Pa, and then indium was vapor-deposited at a rate of 0.03 to 0.08 nm / sec and, at the same time, magnesium was vapor-deposited from the other boat at a rate of 1.7 to 2.8 nm / sec. It was The boat temperature was about 800 ℃ and 500 ℃ for indium and magnesium, respectively. Under the above conditions, a mixed metal electrode of magnesium and indium was laminated and vapor-deposited on the light emitting layer in a thickness of 150 nm to form a counter electrode, thereby forming an element.

Using an ITO electrode as an anode and a mixed metal electrode of magnesium and indium as a cathode, a current of about 6.3 mA / cm ² flows when a DC voltage of 5 V is applied to the obtained device, and the emission brightness is 300 cd /
Green Blue luminescence was obtained at m ² and chromaticity coordinates. The peak wavelength was 486 nm by spectroscopic measurement. Luminous efficiency at this time is 2.9lm / W
Met. When applying DC 7V, the emission brightness is 1000 cd / m ^2.
It was confirmed that the above.

Application example 3 ITO is vapor-deposited on a glass substrate of 25 mm x 75 mm x 1.1 mm.
The transparent support substrate was a film (made by HOYA) having a thickness of 100 nm.

This transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Nippon Vacuum Technology Co., Ltd.), 200 mg of TPDA was put in a resistance heating boat made of molybdenum, and another molybdenum boat was obtained in Example 3. 2,5-bis [2-phenyl-2 (2, which is a 2,5-xylene dimethylidene derivative.
-Naphthyl) vinyl] xylene (NPVX) (200 mg) was added and the pressure in the vacuum chamber was reduced to 1 x 10 ^-4 Pa.

Then, the boat containing TPDA was heated to 215 to 220 ° C., and TPDA was vapor-deposited on the transparent support substrate at a vapor deposition rate of 0.1 to 0.3 nm / sec to form a hole injection layer having a film thickness of 60 nm. The substrate temperature at this time was room temperature.

Next, without taking this out from the vacuum chamber, NPVX was used as a light emitting layer on the hole injection layer from another boat.
80 nm laminated vapor deposition was performed. Deposition conditions are boat temperature of 147 ℃
The deposition rate was 0.2 to 0.4 nm / sec, and the substrate temperature was room temperature.

This was taken out of the vacuum chamber, a stainless steel mask was placed on the light emitting layer, and it was fixed again to the substrate holder.

Next, 1 g of magnesium ribbon was put in a resistance heating boat made of molybden, and 500 mg of indium was attached to another resistance heating boat made of molybden.

After that, the pressure in the vacuum chamber was reduced to 2 × 10 ^-4 Pa, and then indium was vapor-deposited at a rate of 0.03 to 0.08 nm / sec and, at the same time, magnesium was vapor-deposited from the other boat at a rate of 1.7 to 2.8 nm / sec. It was The boat temperature was about 800 ℃ and 500 ℃ for indium and magnesium, respectively. Under the above conditions, a mixed metal electrode of magnesium and indium was laminated and vapor-deposited on the light emitting layer in a thickness of 150 nm to form a counter electrode, thereby forming an element.

The ITO electrode was used as an anode, and the mixed metal electrode of magnesium and indium was used as a cathode.
The current flows about 220mA / cm ² when applying the
I got ish Green luminescence. Peak wavelength is 502 nm from spectroscopic measurement
And the emission luminance was 1000 cd / m ² .

Application Example 4 ITO is vapor-deposited on a glass substrate of 25 mm x 75 mm x 1.1 mm.
The transparent support substrate was a film (made by HOYA) having a thickness of 100 nm.

This transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Nippon Vacuum Technology Co., Ltd.), 200 mg of TPDA was put into a resistance heating boat made of molybdenum, and another molybdenum boat was obtained in Example 5. 2,5-bis [2-phenyl-2-, which is a 2,5-xylene dimethylidene derivative
200 mg of (2-pyridylvinyl] xylene (PPVX) was added and the pressure in the vacuum chamber was reduced to 1 × 10 ⁻⁴ Pa.

Then, the boat containing TPDA was heated to 215 to 220 ° C., and TPDA was vapor-deposited on the transparent support substrate at a vapor deposition rate of 0.1 to 0.3 nm / sec to form a hole injection layer having a film thickness of 60 nm. The substrate temperature at this time was room temperature.

Without taking this out of the vacuum chamber, PPVX as a light emitting layer was laminated in a thickness of 80 nm on the hole injecting layer by another boat. Regarding the vapor deposition conditions, the boat temperature was 198 ° C., the vapor deposition rate was 0.2 to 0.4 nm / sec, and the substrate temperature was room temperature.

This was taken out of the vacuum chamber, a stainless steel mask was placed on the light emitting layer, and it was fixed again to the substrate holder.

Next, 1 g of magnesium ribbon was put in a resistance heating boat made of molybden, and 500 mg of indium was attached to another resistance heating boat made of molybden.

After that, the pressure in the vacuum chamber was reduced to 2 × 10 ^-4 Pa, and then indium was vapor-deposited at a rate of 0.03 to 0.08 nm / sec and, at the same time, magnesium was vapor-deposited from the other boat at a rate of 1.7 to 2.8 nm / sec. It was

The boat temperature was about 800 ℃ and 500 ℃ for indium and magnesium, respectively. Under the above conditions, a mixed metal electrode of magnesium and indium was laminated and vapor-deposited on the light emitting layer in a thickness of 150 nm to form a counter electrode, thereby forming an element.

The ITO electrode was used as an anode, and the mixed metal electrode of magnesium and indium was used as a cathode.
The current flows about 50mA / cm ² when is applied, and Gree
n emission was obtained. The peak wavelength is 513 nm from the spectroscopic measurement,
The emission brightness was 100 cd / m ² .

Application example 5 ITO is vapor-deposited on a glass substrate of 25 mm × 75 mm × 1.1 mm.
The transparent support substrate was a film (made by HOYA) having a thickness of 100 nm.

This transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Nippon Vacuum Technology Co., Ltd.), 200 mg of TPDA was put in a resistance heating boat made of molybdenum, and another molybdenum boat was obtained in Example 8. Then, 200 mg of 2,5-bis (2-phenyl-2-methylvinyl) xylene (MePVX), which is a 2,5-xylene dimethylidyne derivative, was put into the vacuum chamber and the pressure in the vacuum chamber was reduced to 1 × 10 ⁻⁴ Pa.

Thereafter, the boat containing TPDA was heated to 215 to 220 ° C., TPDA was vapor-deposited on the transparent support substrate at a vapor deposition rate of 0.1 to 0.3 nm / sec, to form a hole injection layer having a film thickness of 60 nm. . The substrate temperature at this time was room temperature.

Next, without taking this out from the vacuum chamber, MePVX as another luminescent layer was deposited and deposited on the hole injecting layer in a thickness of 80 nm by another boat. As for the deposition conditions, the boat temperature was 152 ° C, the deposition rate was 0.2 to 0.4 nm / sec, and the substrate temperature was room temperature.
This was taken out of the vacuum chamber, a stainless steel mask was placed on the light emitting layer, and it was fixed again to the substrate holder.

Next, 1 g of magnesium ribbon was put in a resistance heating boat made of molybden, and 500 mg of indium was attached to another resistance heating boat made of molybden. After that, the vacuum chamber is 2 × 10
^After reducing the pressure to ^-4 Pa, indium was started to be deposited at a deposition rate of 0.03 to 0.08 nm / sec and, at the same time, magnesium was deposited from the other boat at a deposition rate of 1.7 to 2.8 nm / sec. The boat temperature was about 800 ℃ and 500 ℃ for indium and magnesium, respectively. Under the above conditions, a mixed metal electrode of magnesium and indium is formed on the light emitting layer at 150 nm.
A device was formed by stacking vapor deposition to form a counter electrode.

With the ITO electrode as the anode and the mixed metal electrode of magnesium and indium as the cathode, a current of about 140 mA / cm ² flows when a DC voltage of 10 V is applied to the resulting device, and Purpl in chromaticity coordinates
I got ish Blue luminescence. Peak wavelength is 438 nm from spectroscopic measurement
And the emission brightness was about ²⁰ cd / m ² .

Application example 6 ITO is vapor-deposited on a glass substrate of 25 mm x 75 mm x 1.1 mm.
The transparent support substrate was a film (made by HOYA) having a thickness of 100 nm. This transparent support substrate was subjected to UV ozone cleaning for 2 minutes by a UV ozone treatment device.

This transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Nippon Vacuum Technology Co., Ltd.), 200 mg of TPDA was put into a resistance heating boat made of molybdenum, and another molybdenum boat was obtained in Example 9. The 4,4'-bis (2-cyclohexyl-2-phenylvinyl) biphenyl (CPVBi), which is a 4,4'-biphenylene dimethylidene derivative,
00 mg was added and the pressure in the vacuum chamber was reduced to 1 × 10 ⁻⁴ Pa.

Thereafter, the boat containing TPDA was heated to 215 to 220 ° C., TPDA was vapor-deposited on the transparent support substrate at a vapor deposition rate of 0.1 to 0.3 nm / sec, and a hole injection layer having a thickness of 60 nm was formed. . The substrate temperature at this time was room temperature.

Next, without taking this out from the vacuum chamber, 80 nm of CPVBi was vapor-deposited as a light emitting layer from another boat on the hole injection layer. As for the vapor deposition conditions, the boat temperature was 210 ° C, the vapor deposition rate was 0.1 to 0.3 nm / sec, and the substrate temperature was room temperature.

This was taken out of the vacuum chamber, a stainless steel mask was placed on the light emitting layer, and it was fixed again to the substrate holder.

Next, 1 g of magnesium ribbon was put in a resistance heating boat made of molybden, and 500 mg of indium was attached to another resistance heating boat made of molybden.

After that, the pressure in the vacuum chamber was reduced to 2 × 10 ^-4 Pa, and then indium was vapor-deposited at a rate of 0.03 to 0.08 nm / sec and, at the same time, magnesium was vapor-deposited from the other boat at a rate of 1.7 to 2.8 nm / sec. It was The boat temperature was about 800 ℃ and 500 ℃ for indium and magnesium, respectively. Under the above conditions, a mixed metal electrode of magnesium and indium was laminated and vapor-deposited on the light emitting layer in a thickness of 150 nm to form a counter electrode, thereby forming an element.

With an ITO electrode as the anode and a mixed metal electrode of magnesium and indium as the cathode, a current of about 14 mA / cm ² flows when a DC voltage of 7.5 V is applied to the obtained device, and Purpli in chromaticity coordinates.
I got sh Blue luminescence. The peak wavelength was 441 nm according to the spectroscopic measurement, and the emission luminance was about 200 cd / m ² .

Application example 7 ITO is vapor-deposited on a glass substrate of 25 mm × 75 mm × 1.1 mm.
The transparent support substrate was a film (made by HOYA) having a thickness of 100 nm. This transparent support substrate was subjected to UV ozone cleaning for 2 minutes by a UV ozone treatment device.

This transparent supporting substrate was fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Nippon Vacuum Technology Co., Ltd.), 200 mg of TPDA was put in a resistance heating boat made of molybdenum, and another molybdenum boat was obtained in Example 10. And 4,4'-bis (2,2-di-p-, which is a 4,4'-biphenylene dimethylidene derivative.
Toluyl vinyl) biphenyl (DTVBi) (200 mg) was added and the vacuum chamber was evacuated to 1 × 10 ^-4 Pa.

Thereafter, the boat containing TPDA was heated to 215 to 220 ° C., TPDA was vapor-deposited on the transparent support substrate at a vapor deposition rate of 0.1 to 0.3 nm / sec, to form a hole injection layer having a film thickness of 60 nm. . The substrate temperature at this time was room temperature.

Next, without removing this from the vacuum chamber, 80 nm of DTVBi was vapor-deposited as a light emitting layer from another boat on the hole injection layer. The vapor deposition conditions are boat temperature 255-271
The deposition rate was 0.1 to 0.3 nm / sec at ℃, and the substrate temperature was room temperature. This was taken out of the vacuum chamber, a stainless steel mask was placed on the light emitting layer, and it was fixed again to the substrate holder.

Next, 1 g of magnesium ribbon was put in a resistance heating boat made of molybden, and 500 mg of indium was attached to another resistance heating boat made of molybden.

After that, the pressure in the vacuum chamber was reduced to 2 × 10 ^-4 Pa, and then indium was vapor-deposited at a rate of 0.03 to 0.08 nm / sec and, at the same time, magnesium was vapor-deposited from the other boat at a rate of 1.7 to 2.8 nm / sec. It was The boat temperature was about 800 ℃ and 500 ℃ for indium and magnesium, respectively. Under the above conditions, a mixed metal electrode of magnesium and indium was laminated and vapor-deposited on the light emitting layer in a thickness of 150 nm to form a counter electrode, thereby forming an element.

Using a ITO electrode as an anode and a mixed metal electrode of magnesium and indium as a cathode, when a direct current voltage of 15 V was applied to the obtained device, a current flowed about 32 mA / cm ² , and blue light emission was obtained in chromaticity coordinates. The peak wavelength was 473 nm by spectroscopic measurement, and the maximum emission luminance was 1000 cd / m ² or more.

Application Example 8 ITO is vapor-deposited on a glass substrate of 25 mm × 75 mm × 1.1 mm.
The transparent support substrate was a film (made by HOYA) having a thickness of 100 nm. This transparent support substrate was subjected to UV ozone cleaning for 2 minutes by a UV ozone treatment device.

This transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Nippon Vacuum Technology Co., Ltd.), 200 mg of TPDA was put into a resistance heating boat made of molybdenum, and another molybdenum boat was obtained in Example 12. In addition, 200 mg of 2,6-bis (2,2-di-p-tolylvinyl) naphthalene (DTVN), which is a 2,6-naphthylene dimethylidene derivative, was placed in a vacuum chamber.
The pressure was reduced to × 10 ^-4 Pa.

After that, the boat containing TPDA is heated to 215 to 220 ° C., TPDA is vapor-deposited on the transparent support substrate at a vapor deposition rate of 0.1 to 0.3 nm / sec to form a hole injection layer having a film thickness of 60 nm. It was The substrate temperature at this time was room temperature.

Next, without taking this out from the vacuum chamber, DTVN was used as a light emitting layer from another boat on the hole injection layer.
80 nm laminated vapor deposition was performed. Deposition conditions are boat temperature of 276-278 ℃
The deposition rate was 0.1 to 0.3 nm / sec, and the substrate temperature was room temperature. This was taken out of the vacuum chamber, a stainless steel mask was placed on the light emitting layer, and it was fixed again to the substrate holder.

Next, 1 g of magnesium ribbon was put in a resistance heating boat made of molybden, and 500 mg of indium was attached to another resistance heating boat made of molybden.

After that, the pressure in the vacuum chamber was reduced to 2 × 10 ^-4 Pa, and then indium was vapor-deposited at a rate of 0.03 to 0.08 nm / sec and, at the same time, magnesium was vapor-deposited from the other boat at a rate of 1.7 to 2.8 nm / sec. It was The boat temperature was about 800 ℃ and 500 ℃ for indium and magnesium, respectively. Under the above conditions, a mixed metal electrode of magnesium and indium was laminated and vapor-deposited on the light emitting layer in a thickness of 150 nm to form a counter electrode, thereby forming an element.

When the direct current voltage of 12 V is applied to the obtained device with the ITO electrode as the anode and the mixed metal electrode of magnesium and indium as the cathode, a current of about 350 mA / cm ² flows, and the chromaticity coordinate is Green.
I got ish Blue luminescence. Peak wavelength is 486 nm from spectroscopic measurement
And the emission brightness was about ²⁰ cd / m ² .

Application example 9 ITO is vapor-deposited on a glass substrate of 25 mm × 75 mm × 1.1 mm.
The transparent support substrate was a film (made by HOYA) having a thickness of 100 nm. This transparent support substrate was subjected to UV ozone cleaning for 2 minutes by a UV ozone treatment device.

This transparent support substrate was fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Nippon Vacuum Technology Co., Ltd.), 200 mg of TPDA was put in a resistance heating boat made of molybdenum, and another molybdenum boat was obtained in Example 13. And 9,10-bis (2,2-di-p which is a 9,10-anthracenediylmethylidyne derivative.
-Toluyl vinyl) anthracene (DTVA) (200 mg) was added, and the pressure in the vacuum chamber was reduced to 1 x 10 ^-4 Pa.

Thereafter, the boat containing TPDA was heated to 215 to 220 ° C., TPDA was vapor-deposited on the transparent support substrate at a vapor deposition rate of 0.1 to 0.3 nm / sec, to form a hole injection layer having a film thickness of 60 nm. . The substrate temperature at this time was room temperature.

Next, without taking this out from the vacuum chamber, DTVA was used as the light emitting layer from the other boat on the hole injection layer.
80 nm laminated vapor deposition was performed. The vapor deposition conditions are boat temperature of 270 ℃,
The deposition rate was 0.1 to 0.3 nm / sec, and the substrate temperature was room temperature.
This was taken out of the vacuum chamber, a stainless steel mask was placed on the light emitting layer, and it was fixed again to the substrate holder.

Next, 1 g of magnesium ribbon was put in a resistance heating boat made of molybden, and 500 mg of indium was attached to another resistance heating boat made of molybden. After that, the vacuum chamber is 2 × 10
^After reducing the pressure to ^-4 Pa, indium was started to be deposited at a deposition rate of 0.03 to 0.08 nm / sec and, at the same time, magnesium was deposited from the other boat at a deposition rate of 1.7 to 2.8 nm / sec. The boat temperature was about 800 ℃ and 500 ℃ for indium and magnesium, respectively. Under the above conditions, a mixed metal electrode of magnesium and indium is formed on the light emitting layer at 150 nm.
A device was formed by stacking vapor deposition to form a counter electrode.

When the direct current voltage of 10 V is applied to the obtained device with the ITO electrode as the anode and the mixed metal electrode of magnesium and indium as the cathode, a current of about 350 mA / cm ² flows and the chromaticity coordinate is Green.
A luminescence was obtained. The peak wavelength is 526 nm from the spectroscopic measurement,
The emission brightness was 400 cd / m ² or more.

Application Examples 10 to 19 An EL device was formed in the same manner as in Application Example 9 except that the light emitting material in Application Example 9 was changed. Table 3 shows these EL emission characteristics.

(Effects of the Invention) The aromatic dimethylidyne compound of the present invention is a novel compound, and at the same time as high brightness EL emission with a brightness of 1000 cd / m ² or more in a range from blue-violet to green, a practical level of brightness (50 Efficient EL emission is obtained at ~ 200 cd / m ² ).

Therefore, the aromatic dimethylidyne compound of the present invention is expected to be effectively used as a light emitting material for EL devices and various light emitting materials.

Claims (2)

(57) [Claims] 1. A general formula [Wherein R ^{1 to} R ⁴ are alkyl groups having 1 to 6 carbon atoms, phenyl groups, p-alkyl substituted phenyl groups, p-phenyl substituted phenyl groups, p-methoxy substituted phenyl groups, p-phenoxy substituted phenyl groups, p-halogen-substituted phenyl group, biphenyl group,
A naphthyl group, a pyridyl group or a cyclohexyl group is shown. R ^{1 to} R ⁴ may be the same or different from each other. Ar represents a 2,5-dialkyl-substituted phenylene group, a biphenylene group, a 3,3'-dialkyl-substituted biphenylene group, a naphthylene group or an anthracenediyl group. ] The aromatic dimethylidene compound represented by these. 2. In the general formula (I), R ^{1 to} R ⁴ are each a methyl group, a phenyl group, a p-alkyl substituted phenyl group, a p-phenyl substituted phenyl group, a p-methoxy substituted phenyl group, a p-phenoxy group. A substituted phenyl group, a p-bromo substituted phenyl group, a cyclohexyl group or a pyridyl group,
The aromatic dimethylidene compound according to claim 1, wherein Ar is a 2,5-dimethyl-substituted phenyl group, a naphthylene group, a biphenylene group, a 3,3'-dimethyl-substituted biphenylene group or an anthracenediyl group.