JP4416546B2 - Organic electroluminescence device - Google Patents

Description

  The present invention relates to an organic electroluminescence element (hereinafter simply referred to as an organic EL element) and a method for producing the same, and more particularly, a novel polycyclic ring that is useful as an electric material and has conductivity or semiconductivity. The present invention relates to an organic electroluminescence device using an organic thin film layer containing an organic silane compound containing a condensed aromatic hydrocarbon skeleton and a method for producing the same.

  Since organic compounds can be converted by chemical reaction of the terminal functional group, when used as a material, they have a high degree of freedom and can provide new functions not found in devices using conventional inorganic materials. It is. Because of these advantages, organic devices have been attracting attention for a long time, and many studies have been made on using them in organic devices such as organic TFTs (organic thin film transistors) and organic ELs. The organic EL element has a structure in which an anode, an organic thin film layer, and a cathode are sequentially laminated on a substrate, and holes injected from the anode and an anode are injected by applying an electric field between the anode and the cathode. It is a self-luminous element that emits a fluorescent substance by recombination energy with electrons. Therefore, for higher device characteristics, it is necessary to develop a transport layer that efficiently transports holes from the anode or electrons from the cathode and to develop a light-emitting layer with high efficiency. Carrier injection at the interface between the electrode and the organic thin film is also important, and how to efficiently inject carriers into the organic thin film is a problem. As a general method for solving the carrier injection, for example, an organic thin film having a LUMO level lower than that of the light emitting layer is prepared as an electron transport layer, and an organic thin film having a HOMO level higher than that of the light emitting layer is prepared as a hole transport layer. Examples of the thin film layer include a multilayer structure of a hole transport layer, a light emitting layer, and an electron transport layer. This is because, when the transport layer is provided between the light emitting layer and the electrode in this way, an effect that carrier injection easily occurs can be obtained as compared with the case of only the light emitting layer. At this time, for example, the light emitting layer is required to have monochromaticity (preferably as the half-value width of the fluorescence spectrum peak is small), high quantum efficiency (preferably as the luminance is high), and low molecular crystallinity (to prevent quenching). In addition, the hole transport layer is required to have high hole mobility as a transport property and high electron withdrawing property for increasing the HOMO level, and the electron transport layer has a high electron mobility as a transport property and a LUMO level. High electron donating property is required to reduce the above.

Under such a background, many research reports have been made on a light emitting layer, a hole transport layer, an electron transport layer, or an interface thereof as an organic EL element. As a technique for improving the light emission efficiency of organic EL by developing materials for the light emitting layer and the transport layer, for example, reports using an organic compound having an acene skeleton have been made (for example, Patent Document 1 and Patent Document 2). These reports are intended to increase the luminous efficiency of the organic EL device by using an organic compound having a tetracene skeleton or a pentacene skeleton in a light emitting layer, a hole transport layer, or an electron transport layer. On the other hand, as a report for improving the interface homogeneity, for example, a method of performing alkylsilane treatment on a metal has been reported (for example, Patent Document 3). This report attempts to improve the hole transport properties to the organic thin film laminated on the anode by surface modification by alkylsilane treatment on the anode.
In the conventional techniques including these reported examples, a method of accumulating organic thin films used as a light emitting layer, a hole transport layer, and an electron transport layer through physical adsorption is common.
Japanese Patent Laid-Open No. 10-36832 JP 2002-93581 A JP-A-8-330071

  However, the organic thin film formed by physical adsorption has a problem in that the durability of the film is low and it deteriorates quickly. Moreover, in order to form organic thin films, such as a light emitting layer, a hole transport layer, or an electron transport layer, by physical adsorption, it is efficient in the interface of an electrode and an organic thin film, or the interface of a light emitting layer, a hole transport layer, or an electron transport layer. However, hole transport or electron transport is not performed, resulting in a problem that a large voltage is required for driving. In particular, in the report in Patent Document 3, the anode / alkylsilane interface is chemisorption, but the interface with the hole transport layer formed thereon is made by physical adsorption. Since alkylsilane is basically insulating, when an organic EL is formed based on this report, it has been a problem that an injection barrier at the anode / hole transport layer interface is formed as a result.

  The present invention has been made in view of the above circumstances, and can efficiently transport holes or electrons at the interface between the electrode and the organic thin film layer and / or the interface between the organic thin film layers, thereby reducing the driving voltage. An object of the present invention is to provide a simple organic EL element.

  The present invention has one or more organic thin film layers between the anode and the cathode, and at least one organic thin film layer is bonded to the anode, cathode or other organic thin film layer through a chemical bond. The organic electroluminescent element characterized by these.

In the organic EL device of the present invention, since at least one organic thin film layer is bonded to an anode, a cathode or another organic thin film layer through a chemical bond, the durability of the device is high, and holes or electrons at the interface are high. Can be efficiently injected. Moreover, since the organic EL element of this invention contains a pi-electron conjugated compound in an organic thin film layer, the mobility of a hole or an electron is large. Therefore, the organic EL element of the present invention can emit light with a relatively small driving voltage.
Since the organic EL device of the present invention contains a compound having an acene skeleton that emits light in an organic layer, it can also be used as a single-layer device having only an organic layer containing the compound as a light emitting layer between electrodes. On the other hand, the effect is particularly great when the organic EL device of the present invention is a multilayer device having a plurality of organic layers between electrodes. That is, by using an organic silane compound in which an electron-withdrawing group or electron-donating group is introduced into the acene skeleton, the organic thin film layer containing the compound can be used as a hole transport layer or an electron transport layer. . Among them, the organosilane compound used in the present invention has a π-electron conjugated molecule and a silicon atom, and has an effect of electron attraction by direct bonding thereof. The organic EL element is particularly excellent in performance such as electron transfer characteristics, and can realize high luminous efficiency at a lower driving voltage.

(Configuration of organic EL element)
The organic EL device of the present invention has one or more organic thin film layers between an anode and a cathode.
As the anode and the cathode, any electrode conventionally used in the field of organic EL devices can be used. Specifically, the anode is usually a thin film having a high light transmittance and a high hole injection property, such as indium tin oxide (ITO), SnO ₂ , indium tin oxide, zinc oxide, indium zinc oxide. Metal oxides such as products or mixed metal oxides can be used, metals having a high work function such as gold, or PEDOT (poly [3,4- (ethylene-1,2-dioxy) thiophene]), polyaniline, polypyrrole, polythiophene, and the like, and conductive polymers obtained by adding a dopant such as an electrolyte. As the cathode, a thin film having high electron injection characteristics is usually used. For example, an alloy such as a lithium-aluminum alloy or a magnesium-silver alloy, or magnesium, calcium, or lithium fluoride (LiF) / aluminum, lithium Examples thereof include an electrode having a two-layer structure such as oxide (Li ₂ O) / aluminum.

As the organic thin film layer, for example, one or more organic thin film layers selected from the group consisting of an electron transport layer, a hole transport layer, and a light emitting layer are used in combination. Examples of the configuration of the organic EL device of the present invention using such an organic thin film layer include the following specific examples.
Configuration (1): anode-light emitting layer-cathode,
Configuration (2); anode-hole transport layer-light emitting layer-cathode,
Configuration (3); anode-light-emitting layer-electron transport layer-cathode, and configuration (4); anode-hole transport layer-light-emitting layer-electron transport layer-cathode.

  Regardless of the configuration of the organic EL device of the present invention, at least one organic thin film layer, for example, at least one organic thin film layer selected from an electron transport layer, a hole transport layer, and a light emitting layer, The organic silane compound detailed in the above is contained. When the organic silane compound is contained, the organic silane compound and the layer in which the organic silane compound-containing layer is formed, for example, an anode, a cathode, or another organic thin film layer reacts and is chemically bonded as a result. The organic silane compound-containing layer and the layer in which the layer is formed are firmly bonded by chemical bonding. For this reason, carriers such as holes and electrons are efficiently injected and moved at the interface between these layers, and the overall light emission efficiency is improved, and the drive voltage can be effectively reduced. Therefore, it is preferable from the viewpoint of carrier injection that an organic silane compound is contained in all organic thin film layers and chemical bonding is performed at all interfaces of the organic EL element, but a material having a higher quantum yield is used. From the viewpoint of increasing the light emission characteristics of the light emitting layer itself by using it in the light emitting layer, it is more preferable that only the electrode and the transport layer are bonded via a chemical bond. Furthermore, in terms of the production efficiency of the organic EL element, it is most preferable that only the transport layer and the electrode closer to the substrate are bonded via a chemical bond, and this structure also improves the hole / electron transport efficiency. Can do. That is, in general, considering that an organic EL device is manufactured by sequentially laminating an anode, a desired organic thin film layer and a cathode on a transparent substrate, the hole transport layer and the anode are bonded via a chemical bond. Is more preferable.

  For example, when the organic EL element has the configuration (1), the organic thin film layer is only a light emitting layer, and the light emitting layer contains an organosilane compound. In this case, the light emitting layer is bonded to at least a lower electrode (for example, an anode) through a chemical bond. Such a light emitting layer may be composed of an organic silane compound alone, or may be composed of a mixture of an organic silane compound and another light emitting material. The other light-emitting substance is not particularly limited as long as it is a substance conventionally used as a light-emitting substance for an organic EL device. For example, tris (8-quinolinolato) aluminum (Alq3), styryl compound Benzoxazole derivatives and metal complexes thereof, benzimidazole derivatives and metal complexes thereof, polymers such as poly (p-phenylenevinylene) and derivatives or copolymer derivatives thereof, polyfluorene ) And derivatives thereof.

For example, when an organic EL element has the said structure (2), an organosilane compound is contained only in at least one layer of a positive hole transport layer or a light emitting layer, Preferably it is a positive hole transport layer. When the hole transport layer contains an organosilane compound, the hole transport layer is bonded to the anode via a chemical bond. Such a hole transport layer may be composed of an organosilane compound alone, or may be composed of a mixture of an organosilane compound and another hole transport material. The other hole transport material is not particularly limited as long as it is a material conventionally used as a hole transport material of an organic EL device. For example, N, N′-diphenyl-N, N′-bis (4 Triphenyldiamine compounds such as -methylphenyl) -4,4'-diamine (TPD), phenylenediamine compounds such as N, N, N ', N'-tetra- (m-toluyl) -m-phenylenediamine, 3 , 5-Dimethyl-3'5'-ditertiarybutyl-4,4'-diphenoquinone and other diphenoquinone compounds, 2- (4-biphenyl) -5- (4-tertiarybutylphenyl) -1,3,4 -Oxadiazole compounds such as oxadiazole and the like. The mixing ratio of the organosilane compound and the other hole transporting material may be mixed so that the ratio of the organosilane compound is in the range of 1% by weight to 100% by weight. Since the amount of pores changes, it is preferable to adjust the mixing amount so as to obtain an appropriate injection. In particular, when an organosilane compound and another hole transport material have different energy levels and mobility for holes, the compound is selected and the optimum mixing ratio is found, so that the structure of the light emitting device can be obtained. It is desirable to adjust the optimal hole concentration. The hole transport layer in the case where no organic silane compound is contained in the hole transport layer may be composed of the other hole transport material.
When the organic silane compound is contained in the light emitting layer, the light emitting layer is bonded to the hole transport layer through a chemical bond. The light emitting layer constituting material in such a case is the same as that of the light emitting layer of the above configuration (1). When the organic silane compound is not contained in the light emitting layer, the light emitting layer only needs to be composed of another light emitting material having the above configuration (1).

For example, when an organic EL element has the said structure (3), an organosilane compound is contained only in at least one layer of an electron carrying layer or a light emitting layer, Preferably it is an electron carrying layer. When the electron transport layer contains an organosilane compound, the electron transport layer is bonded to the light emitting layer through a chemical bond. Such an electron transport layer may be composed of an organosilane compound alone, or may be composed of a mixture of an organosilane compound and another electron transport material. The other electron transport material is not particularly limited as long as it is a material conventionally used as an electron transport material for an organic EL device. Note that the electron transport layer may not be formed as long as the light emitting layer has the property of being able to transport electrons simultaneously with the property of emitting light, such as Alq3. An example of a typical electron transporting material is Alq3, but a phthalocyanine copper complex compound can also be used. The mixing ratio of the organosilane compound and the other electron transporting material may be mixed so that the ratio of the organosilane compound is in the range of 1% by weight to 100% by weight. Since the amount changes, it is preferable to adjust the mixing amount so as to obtain an appropriate injection. In particular, when an organosilane compound and another electron transport material have different energy levels and mobility with respect to electrons, the compound is selected, and the optimum mixing ratio is found, so that it is optimal for the structure of the light emitting device. It is desirable to adjust the electron concentration. The electron transport layer in the case where no organic silane compound is contained in the electron transport layer may be composed of the other electron transport material.
When the organic silane compound is contained in the light emitting layer, the light emitting layer is bonded to the anode through a chemical bond. The light emitting layer constituting material in such a case is the same as that of the light emitting layer of the above configuration (1). When the organic silane compound is not contained in the light emitting layer, the light emitting layer only needs to be composed of another light emitting material having the above configuration (1).

For example, when the organic EL element has the above configuration (4), as shown in FIG. 1, a hole transport layer 2, a light emitting layer 3, an electron transport layer 4 and a cathode 5 are sequentially laminated on the anode 1. It has become. From the viewpoint of manufacturing efficiency, the anode 1 is usually formed on the substrate 6 in advance. In this case, the organosilane compound is contained in at least one layer of the hole transport layer, the electron transport layer or the light emitting layer, preferably only one of the hole transport layer or the electron transport layer, particularly only the electron transport layer. .
When the electron transport layer contains an organosilane compound, the electron transport layer is bonded to the light emitting layer through a chemical bond. The electron transport layer constituting material in such a case is the same as the electron transport layer of the above configuration (3). The electron transport layer in the case where no organic silane compound is contained in the electron transport layer may be composed of another electron transport material of the above configuration (3).
When the hole transport layer contains an organosilane compound, the hole transport layer is bonded to the anode via a chemical bond. The hole transport layer constituting material in such a case is the same as the hole transport layer of the above configuration (2). The hole transport layer in the case where no organic silane compound is contained in the hole transport layer may be composed of another hole transport material of the above configuration (2).
When the organic silane compound is contained in the light emitting layer, the light emitting layer is bonded to the hole transport layer through a chemical bond. The light emitting layer in such a case is the same as the light emitting layer having the above configuration (1). When the organic silane compound is not contained in the light emitting layer, the light emitting layer only needs to be composed of another light emitting material having the above configuration (1).

(Organic silane compound)
The organic silane compound contained in the organic EL device of the present invention will be described.
In the present invention, the organic silane compound has a functional group and a specific silyl group in a polycyclic fused aromatic hydrocarbon skeleton (hereinafter simply referred to as a polycyclic skeleton). The functional group and the silyl group are the same as the functional group and the silyl group, respectively, that the organosilane compound represented by the general formula (I) described later can have.

  Since the organosilane compound has a specific silyl group in the polycyclic skeleton, a reaction occurs between the silyl group and the layer on which the organosilane compound-containing layer is to be formed. As a result, the organosilane compound-containing layer The layer in which the layer is to be formed is firmly bonded by a chemical bond. In addition, since the organosilane compound has a polycyclic skeleton and a functional group, it can be made amorphous while reducing the interaction between adjacent molecules while ensuring excellent conductivity. improves. Furthermore, the presence of a silyl group having a hydroxyl group by hydrolysis and a functional group having a relatively high hydrophobicity improves the surface activity of the organosilane compound, so that the compound molecules are appropriately ordered in the same direction during film formation. Line up efficiently. Therefore, the conductivity of the organosilane compound can be further improved and the film formation time can be shortened. When the functional group has a relatively high hydrophobicity, the solubility of the organosilane compound in the organic solvent is enhanced, and the compound using the organic solvent can be applied, thereby improving versatility.

  The polycyclic skeleton contained in the organic silane compound is not particularly limited as long as it has a π-electron conjugated molecular structure, and those having symmetry, particularly line symmetry, are preferable from the viewpoint of conductivity. Specific examples of such preferred skeletons include, for example, an acene skeleton that is a linear condensed ring system, an aphene skeleton that is a winged condensed ring system, and a condensed ring system in which two identical rings are aligned. There is an phenylene (-phenylene) skeleton, which is a condensed ring system in which benzene rings are concentrated around one ring. However, considering the carrier mobility, an acene skeleton or a phenylene skeleton in which benzene rings are bonded linearly is particularly preferable. Specific examples of the acene skeleton include naphthalene, anthracene, tetracene (naphthacene), pentacene, hexacene, heptacene, octacene and the like. Examples of the phenylene skeleton include phenalene, perylene, coronene, and ovalen. Hereinafter, the case where the organosilane compound has an acene skeleton and the case where the organosilane compound has a phenylene skeleton will be described in detail. However, the description of the case of having another skeleton conforms to the following description.

によって表される。以下、当該化合物を有機シラン化合物（Ｉ）という。 The organosilane compound of the present invention having an acene skeleton is represented by the general formula (I);

Represented by Hereinafter, the compound is referred to as an organosilane compound (I).

  In the formula (I), m is an integer of 0 to 10, and an integer of 2 to 8, particularly 2 to 4 is preferable from the viewpoint of yield.

At least one group among R ^{1 to} R ¹⁰ , preferably 1 or 2, particularly 2 groups is represented by the general formula (i);
-SiX ¹ X ² X ³ (i)
In which at least one group is a functional group, and the other group is a hydrogen atom. When m is 2 or more, all R ⁷ and R ⁸ may be the same or different.

In formula (i), at least one of the X ^{1 to} X ³ groups of the silyl group is a group that gives a hydroxyl group by hydrolysis or a halogen atom, and other groups do not react with adjacent molecules. It is a group. Thus, since the silyl group has one or more groups that give hydroxyl groups by hydrolysis or halogen atoms, a strong bond (chemical bond) between the compound and the layer in which the layer containing the compound is formed is achieved, and the carrier The injection efficiency is improved.

Examples of the group that gives a hydroxyl group by hydrolysis include an alkoxy group having 1 to 4 carbon atoms, preferably 1 to 3 carbon atoms, particularly 1 to 2 carbon atoms, and a linear one is preferable. Specific examples include a methoxy group, an ethoxy group, an n-propoxy group, a 2-propoxy group, an n-butoxy group, a sec-butoxy group, and a tert-butoxy group. In the alkoxy group, part of hydrogen may be further substituted with another substituent, for example, a trialkylsilyl group (the alkyl group has 1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), or the like.
Examples of the halogen atom include a fluorine atom, a chlorine atom, an iodine atom, and a bromine atom, and a chlorine atom is preferable in consideration of reactivity.
When the silyl group has two or more halogen atoms or groups that give a hydroxyl group by hydrolysis, these groups may be partially or completely the same or different.

  Examples of the group that does not react with an adjacent molecule that the silyl group may have include a substituted or unsubstituted alkyl group, cycloalkyl group, aryl group, diarylamino group, or di- or triarylalkyl group. . A substituted or unsubstituted alkyl group is preferable. From the viewpoint of reducing intermolecular interaction, the group that does not react with adjacent molecules has a molecular volume within a range that does not inhibit the binding between the organosilane compound and the layer formed on the surface. A comparatively large thing is preferable, More preferably, it is spreading radially. This is because when the intermolecular interaction between adjacent molecules is reduced, the organic thin film becomes amorphous and the luminous efficiency of the organic EL is further improved.

The alkyl group preferably has 1 to 10 carbon atoms, particularly 1 to 4 carbon atoms, and more preferably has a branched shape. Specifically, methyl group, ethyl group, n-propyl group and sec-propyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group And decyl group. Examples of the alkyl group having 1 to 4 carbon atoms include methyl group, ethyl group, n-propyl group and sec-propyl group, n-butyl group, sec-butyl group, and tert-butyl group.
The cycloalkyl group preferably has 4 to 8 carbon atoms, particularly 5 to 7 carbon atoms, and specific examples thereof include a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.

The aryl group is preferably a group composed of 1 to 3 aromatic rings having 5 to 18 carbon atoms, particularly 6 carbon atoms. A sulfur atom may be contained as a hetero atom. The aryl group may have at least one alkyl group having 1 to 4 carbon atoms in any of the o-position, m-position and p-position. Examples of the alkyl group having 1 to 4 carbon atoms include methyl group, ethyl group, propyl group, sec-propyl group, butyl group, sec-butyl group, and tert-butyl group. Specific examples of the aryl group include a phenyl group, biphenylyl group, naphthyl group, terphenylyl, p- (tert-butyl) phenyl group, m-diethylphenyl group, p-propylbiphenylyl group and the like. Terphenylyl is a residue obtained by removing one hydrogen atom from terphenyl.
The diarylamino group is an amino group in which two hydrogen atoms are substituted with an aryl group, and the included aryl group is the same as described above. Specific examples of the diarylamino group include, for example, an N, N-diphenylamino group, an N, N-di (biphenylyl) amino group, an N, N-di (terphenylyl) amino group, an N-phenylN-biphenylylamino group, N-phenyl N-terphenylylamino group, N-biphenylyl N-terphenylylamino group, N, N-dinaphthylamino group, N-phenyl N-naphthylamino group, N-biphenylyl N-naphthylamino group, N -Terphenylyl N-naphthylamino group, N-methylphenyl-N-biphenylylamino group, N-methylphenyl-N-naphthylamino group, N-methylphenyl-N-phenylamino group, N, N-di (methylphenyl) ) Amino group and the like.

  The di- or triarylalkyl group is preferably a linear alkyl group having 1 to 4 carbon atoms in which 2 or 3 hydrogen atoms are substituted with an aryl group, and the included aryl group is the same as described above. Examples of the linear alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an n-butyl group, and any group of these groups may have an aryl group. However, considering the steric effect, it is preferable to have at the end. Specific examples of diarylalkyl groups include, for example, dimethylmethyl, diphenylmethyl, di (biphenylyl) methyl, di (terphenylyl) methyl, phenylbiphenylylmethyl, phenylterphenylylmethyl, biphenylylterphenylyl Methyl group, dinaphthylmethyl group, phenylnaphthylmethyl group, biphenylylnaphthylmethyl group, terphenylylnaphthylmethyl group, methylphenyl-biphenylylmethyl group, methylphenyl-naphthylmethyl group, methylphenyl-phenylmethyl group, di ( Methylphenyl) methyl group, diphenylethyl group, di (biphenylyl) ethyl group, di (terphenylyl) ethyl group, phenylbiphenylylethyl group, phenylterphenylylethyl group, biphenylylterphenylylethyl group, dinaphthyl Ethyl group, phenylnaphthylethyl group, biphenylylnaphthylethyl group, terphenylylnaphthylethyl group, methylphenyl-biphenylylethyl group, methylphenyl-naphthylethyl group, methylphenyl-phenylethyl group, di (methylphenyl) ethyl group Diphenylpropyl group, di (biphenylyl) propyl group, di (terphenylyl) propyl group, phenylbiphenylylpropyl group, phenylterphenylylpropyl group, biphenylylterphenylylpropyl group, dinaphthylpropyl group, phenylnaphthylpropyl group, Biphenylylnaphthylpropyl group, terphenylylnaphthylpropyl group, methylphenyl-biphenylylpropyl group, methylphenyl-naphthylpropyl group, methylphenyl-phenylpropyl group, di (methylphenyl) L) propyl group, diphenylbutyl group, di (biphenylyl) butyl group, di (terphenylyl) butyl group, phenylbiphenylylbutyl group, phenylterphenylylbutyl group, biphenylylterphenylylbutyl group, dinaphthylbutyl group, phenyl Naphtylbutyl group, biphenylylnaphthylbutyl group, terphenylylnaphthylbutyl group, methylphenyl-biphenylylbutyl group, methylphenyl-naphthylbutyl group, methylphenyl-phenylbutyl group, di (methylphenyl) butyl group, etc. . Specific examples of the triarylalkyl group include, for example, a trimethylmethyl group, a triphenylmethyl group, a tri (biphenylyl) methyl group, a tri (terphenylyl) methyl group, a phenyl-di (biphenylyl) methyl group, and a di (phenyl) terphenyl. Rylmethyl group, phenyldi (terphenylyl) methyl group, trinaphthylmethyl group, phenyldi (naphthyl) methyl group, di (phenyl) naphthylmethyl group, di (terphenylyl) naphthylmethyl group, methylphenyl-di (phenyl) methyl group, methyl Phenyl-di (naphthyl) methyl group, methylphenyl-di (biphenylyl) methyl group, tri (methylphenyl) methyl group, triphenylethyl group, tri (biphenylyl) ethyl group, tri (terphenylyl) ethyl group, phenyl-di ( Biphenylyl) ethyl group Di (phenyl) terphenylylethyl group, phenyldi (terphenylyl) ethyl group, trinaphthylethyl group, phenyldi (naphthyl) ethyl group, di (phenyl) naphthylethyl group, di (terphenylyl) naphthylethyl group, methylphenyl-di ( Phenyl) ethyl group, methylphenyl-di (naphthyl) ethyl group, methylphenyl-di (biphenylyl) ethyl group, tri (methylphenyl) ethyl group and the like.

  When the silyl group has two groups that do not react with the adjacent molecule, these groups may be the same or different.

Organic silane compound (I), as long as at least one group of R ¹ to R ¹⁰ is a silyl group, may be any group is a silyl group, considering the conductivity preferably R ¹ ~ It is preferable that at least one group of R ⁴ is a silyl group.

  When the organosilane compound (I) of the present invention has two or more silyl groups, part or all of these groups may be the same or different.

  The functional group that the organosilane compound (I) of the present invention can have has the effect of improving the solubility in organic solvents and the formation of an amorphous film by reducing the intermolecular interaction when forming an organic thin film. And a group responsible for destabilizing the HOMO level or stabilizing the LUMO level of the compound. In this case, the functional group is preferably a group that does not react with an adjacent molecule from the viewpoint of reaction control. From the viewpoint of improving the solubility in an organic solvent, the functional group preferably has hydrophobicity. From the viewpoint of the action of forming an amorphous film, the functional group preferably has a large molecular volume. From the viewpoint of destabilizing the HOMO level or stabilizing the LUMO level of the compound, the functional group is preferably a group having an electron donating property or an electron withdrawing property. The functional group is most preferably one satisfying any of these action conditions, but the functional group is not limited to one having hydrophobicity. When the functional group has an electron-withdrawing property, the electron-withdrawing group is often hydrophilic, but the compound of the present invention (electron transporting substance) having such a hydrophilic electron-withdrawing group as a functional group This is because the solubility in organic solvents can be sufficiently ensured.

  Examples of preferred functional groups include, for example, substituted or unsubstituted alkyl groups, halogenated alkyl groups, cycloalkyl groups, aryl groups, diarylamino groups, di- or triarylalkyl groups, alkoxy groups, oxyaryl groups, nitriles. Group, nitro group, ester group and the like. Considering the stability of the functional group, a nitrile group or a nitro group is more preferable.

An alkyl group as a functional group, a cycloalkyl group, an aryl group, a diarylamino group, a di- or triarylalkyl group, each of the silyl group may have an alkyl group as a “group that does not react with an adjacent molecule”; The same as the cycloalkyl group, aryl group, diarylamino group, di- or triarylalkyl group.
The alkoxy group preferably has 1 to 6 carbon atoms, particularly 3 to 4 carbon atoms, and may be linear or branched, but more preferably is branched. Preferable specific examples include 2-propyloxy group, sec-butyloxy group, tert-butyloxy group and the like.
The oxyaryl group is a group in which a hydrogen atom of a hydroxyl group is substituted with an aryl group, and the included aryl group is the same as the aryl group as a “group that does not react with an adjacent molecule” that a silyl group may have. It is. Specific examples of the oxyaryl group include a phenyloxy group, a biphenylyloxy group, a naphthyloxy group, and the like.

The halogenated alkyl group preferably has 1 to 10 carbon atoms, particularly 1 to 4 carbon atoms. Specific examples thereof include a monochloroethyl group, a trifluoroethyl group, and a trichloroethyl group.
The ester group is represented by —COOR ′ or —OCOR ′ (R ′ is an alkyl group or an aryl group, and they are the same as the alkyl group or aryl group as “groups that do not react with adjacent molecules”, respectively). Group. As specific examples, for example, —COOCH ₃ , —COOCH ₂ CH ₃ , —COO (CH ₂ ) ₂ CH ₃ , —COOCH (CH ₃ ) ₂ , —COO (CH ₂ ) ₃ CH ₃ , —COOCH (CH ₃ ) _{CH 2 CH 3, -COOC (CH} 3) 3, -COOPh, -COO (Ph) 2, -COO (Ph) 3, -OCOCH 3, -OCOCH 2 CH 3, -OCO (CH 2) 2 CH 3, _{-OCOCH (CH 3) 2, -OCO} (CH 2) 3 CH 3, -OCOCH (CH 3) CH 2 CH 3, -OCOC (CH 3) 3, -OCOPh, -OCO (Ph) 2, -OCO ( Ph) ₃ (Ph is a phenyl group) and the like.

The organic silane compound (I) may be any functional group as long as at least one of R ^{1 to} R ¹⁰ is a functional group. In consideration, it is preferable that 1 to 6, particularly 1 to 4 groups out of R ^{3 to} R ¹⁰ are functional groups. That is, if it does not have a functional group, the solubility of the compound in an organic solvent is extremely low. On the other hand, when the number of functional groups is more than 6, it is difficult to introduce such a number of functional groups into the polycyclic skeleton due to the steric effect of the functional groups.

  When the organosilane compound (I) of the present invention has two or more functional groups, a part or all of these groups may be the same or different.

  For example, when the organic silane compound (I) is contained in the light emitting layer, the organic silane compound (I) is not particularly limited as long as it is within the above range, but the functional group is a substituted or unsubstituted alkyl group among the above. , A diarylamino group, or a di or triarylalkyl group is preferably used. At this time, the silyl group is not particularly limited and may be the same as described above. For example, when an organic thin film is formed by mixing an organic silane compound in the general formula (I) where m is within the above range with Alq3, m = 4 (575 nm), m = 5 (620 nm), m = 6 (625 nm, respectively. ), M = 7 (630 nm), and m = 8 (635 nm).

  Further, for example, when the organosilane compound (I) is contained in the electron transport layer, the organosilane compound (I) is a group in which the functional group has an electron donating property among the above (substituent constant s based on Hammett's rule is 0). For example, an alkyl group, a cycloalkyl group, an aryl group, a diarylamino group, a di- or triarylalkyl group, an alkoxy group, an oxyaryl group, or the like is used. At this time, the silyl group is not particularly limited and may be the same as described above.

  Further, for example, when the organic silane compound (I) is contained in the hole transport layer, the organic silane compound (I) is a group in which the functional group has electron withdrawing property among the above (the substituent constant s based on the Hammett rule is 0 or less), for example, a halogenated alkyl group, a nitrile group, a nitro group, an ester group and the like are used. At this time, the silyl group is not particularly limited and may be the same as described above.

In the case where the organosilane compound (I) is contained in any of the light emitting layer, the electron transport layer, and the hole transport layer, the structure of the compound is symmetric, particularly line symmetric, in consideration of the light emission efficiency and the crystallinity control. It is preferable to have properties. That is, in the general formula (I), R ¹ is R ² , R ³ is R ⁴ , R ⁵ is R ⁶ , R ⁷ is R ⁸ , R ⁹ is R ¹⁰ , Preferably there is. In particular, R ³ is preferably the same substituent as R ⁴ , R ⁵ is R ⁶ , R ⁷ is R ⁸ , and R ⁹ is R ¹⁰ .

Specific examples of the organosilane compound (I) of the present invention are shown below.

及び一般式（III）：

によって表される。以下、一般式（II）の化合物を有機シラン化合物（II）、一般式（III）の化合物を有機シラン化合物（III）という。有機シラン化合物（II）及び（III）が有する骨格は、いずれもベンゼン環がジグザグに結合されてなるアセン骨格である。便宜上、ベンゼン環のユニット数を上記一般式中に示す形で指定する。また、置換基の結合位置および種類をＲｎ−ｍとして指定する。本発明の有機シラン化合物（II）および（III）のいずれにおいても、ベンゼン環の総ユニット数ｎは３〜７のものが好ましい。
一般式（II）のアセン骨格の好ましい具体例として、例えば、フェナントレン骨格、クリセン骨格、ピセン骨格等が挙げられる。
一般式（III）のアセン骨格の好ましい具体例として、例えば、ピレン骨格、アントアントレン骨格等が挙げられる。 The organosilane compound of the present invention having an acene skeleton different from the above is represented by the general formula (II):

And general formula (III):

Represented by Hereinafter, the compound of general formula (II) is referred to as organosilane compound (II), and the compound of general formula (III) is referred to as organosilane compound (III). The skeletons of the organosilane compounds (II) and (III) are both acene skeletons in which benzene rings are bonded in a zigzag manner. For convenience, the number of units of the benzene ring is specified in the form shown in the above general formula. In addition, the bonding position and type of the substituent are designated as Rn-m. In any of the organosilane compounds (II) and (III) of the present invention, the total number n of benzene rings is preferably 3 to 7.
Preferable specific examples of the acene skeleton of the general formula (II) include, for example, a phenanthrene skeleton, a chrysene skeleton, and a picene skeleton.
Preferable specific examples of the acene skeleton of the general formula (III) include, for example, a pyrene skeleton and an anthrene skeleton.

  In formulas (II) and (III), at least one group among all groups represented by Rn-m is a silyl group, and at least one, preferably 1-4 groups are functional groups. And all other groups are hydrogen atoms. The silyl group and the functional group are the same as the silyl group and the functional group in the formula (I), respectively.

によって表される。以下、当該化合物を有機シラン化合物（IV）という。 The organosilane compound of the present invention having a perylene skeleton has the general formula (IV);

Represented by Hereinafter, this compound is referred to as an organosilane compound (IV).

In the formula (IV), at least one group among R ^{11 to} R ²² , preferably 1-2 groups are silyl groups, and at least one group, preferably 1-4 groups are functional. The other group is a hydrogen atom. In the formula (IV), the silyl group and the functional group are the same as the silyl group and the functional group in the formula (I), respectively.

  When the organosilane compound (IV) of the present invention has two or more silyl groups, some or all of these groups may be the same or different.

  When the organosilane compound (IV) of the present invention has two or more functional groups, part or all of these groups may be the same or different.

Further, when the organic silane compound (IV) is used as an organic EL material, it is preferable that the structure of the compound has symmetry, particularly point symmetry, in view of luminous efficiency. That is, in the general formula (IV), R ¹¹ is R ¹⁷ , R ¹² is R ¹⁸ , R ¹³ is R ¹⁹ , R ¹⁴ is R ²⁰ , R ¹⁵ is R ²¹ , and R ¹⁶ is R ²² . These are preferably the same substituents.

Specific examples of the organosilane compound (IV) of the present invention are shown below.

(Synthesis method)
The organosilane compound of the present invention can be synthesized, for example, by introducing a functional group and a silyl group into a polycyclic skeleton-containing molecule.

  The polycyclic skeleton-containing molecule is available as a commercial product. For example, (A) a method in which a triflate group is inserted at a predetermined position of the raw material, then reacted with a furan derivative, and subsequently oxidized (see routes A1 to A5), And (B) after providing an acetylene derivative at a predetermined position of the raw material, the acetylene groups can be synthesized by a ring-closing reaction (see routes B1 to B5). In particular, when the above method (A) is employed, a functional group can be introduced simultaneously with the synthesis of a polycyclic skeleton-containing molecule by introducing a functional group into a furan derivative or a raw material in advance (route A1). To A5). Moreover, when employ | adopting the said method (B), a functional group can be introduce | transduced simultaneously with the synthesis | combination of a polycyclic skeleton containing molecule | numerator by introduce | transducing a functional group into a raw material previously (refer route B1). An example of a synthetic route for a polycyclic skeleton-containing molecule using these techniques is shown below.

（式中、Ｒ_ａおよびＲ_ｂはそれぞれ独立して前記機能性基と同様である）

(Wherein, R _a and R _b are each independently the same as the functional group)

（式中、Ｒ_ａおよびＲ_ｂはそれぞれ独立して前記機能性基と同様である）

(Wherein, R _a and R _b are each independently the same as the functional group)

  The functional group can be introduced by halogenating a predetermined part of the polycyclic skeleton, if desired, and reacting with the functional group-containing compound. This is not necessary if a functional group has already been introduced.

The functional group-containing compound can introduce a functional group at the site by reaction with the halogenated site of the polycyclic skeleton-containing molecule.
Specifically, for example, when the functional group is an alkyl group, a cycloalkyl group, an aryl group, a di- or triarylalkyl group, a Grignard reagent having the functional group can be used. Also, for example, when the functional group is a diarylamino group, diarylamine can be used. For example, when the functional group is an alkoxy group or an oxyaryl group, an alcohol having these groups can be used. For example, when the functional group is a halogenated alkyl group, a Grignard reagent having the functional group can be used. Further, for example, when the functional group is a nitrile group, a nitro group, or an ester group, it is possible to use a method in which the functional group is imparted in the synthesis process from the raw material compound and the subsequent reaction route is made a gentle route. When a mild reaction route cannot be selected, a protection / deprotection reaction can be used before and after the reaction. Examples of the protective group used in the protection / deprotection reaction include a trimethoxysilyl group.

  The reaction conditions for introducing the functional group are not particularly limited as long as the functional group can be introduced. Usually, the reaction may be refluxed in an organic solvent that does not affect the reaction for 1 to 48 hours. As the organic solvent that does not affect the reaction, the same organic solvent as described below can be used.

The silyl group is optionally halogenated at a predetermined site of the polycyclic skeleton, and has the general formula:
X ⁴ -SiX ¹ X ² X ³
(Wherein X ^{1 to} X ³ are the same as those described above; X ⁴ is a hydrogen atom or a halogen atom, for example, a fluorine atom, a chlorine atom, a bromine atom or an iodine atom, preferably a hydrogen atom or a chlorine atom. It can be introduced by reacting with a silane derivative represented by the following formula (hereinafter simply referred to as a silane derivative). There is no need for halogenation if a given site is already halogenated.

  Specific examples of preferable silane derivatives include, for example, triethoxysilane, di (t-butyl) monomethoxysilane, and tetrachlorosilane.

  The reaction conditions for introducing the silyl group are not particularly limited as long as the silyl group can be introduced. Specifically, the reaction temperature is, for example, −100 to 150 ° C., preferably −20 to 100 ° C. The reaction time is, for example, about 0.1 to 48 hours. The reaction is usually carried out in an organic solvent that does not affect the reaction. Examples of organic solvents that do not affect the reaction include aliphatic hydrocarbons such as hexane and pentane, ethers such as diethyl ether, dipropyl ether, dioxane, and tetrahydrofuran (THF), and aromatics such as benzene, toluene, and nitrobenzene. Examples include hydrocarbons, and chlorinated hydrocarbons such as methylene chloride, chloroform, and carbon tetrachloride. These can be used alone or as a mixed solution. Among these, ethers, chlorinated hydrocarbons, and aromatic hydrocarbons are preferable, and THF, diethyl ether, chloroform, nitrobenzene, and toluene are particularly preferable. The reaction may optionally use a catalyst. A known catalyst can be used as the catalyst, and examples thereof include a copper catalyst, a platinum catalyst, a palladium catalyst, and a nickel catalyst.

  When a residue such as a trimethylsilyl group is present at a predetermined position of the polycyclic skeleton and halogenation is difficult to occur, a silyl group may be introduced based on the reaction shown below. The starting material for the following reaction is a polycyclic skeleton-containing molecule synthesized by Route A1.

  An example of a route for introducing a functional group and a silyl group is shown below.

  The organosilane compound of the present invention obtained by such a method is isolated and purified from the reaction solution by a known means such as phase transfer, concentration, solvent extraction, fractional distillation, crystallization, recrystallization, chromatography and the like. Can do.

(Manufacturing method of organic EL element)
The organic EL device of the present invention is usually formed by sequentially laminating an anode, each organic thin film layer and a cathode on a substrate.
The substrate material is not particularly limited, but a transparent or translucent material is preferable in consideration of taking out emitted light from the substrate side. Therefore, for example, glass or plastic having an amorphous property is preferably used, and a substrate having an appropriate mechanical strength and surface flatness such as a metal or a wafer can be used depending on an application.

  The anode and the cathode can be formed by employing a vapor deposition method such as a vacuum deposition method or a molecular beam deposition method, or a vapor phase method such as a sputtering method such as an RF sputtering method. The thicknesses of the anode and the cathode are not particularly limited, and usually may be 50 to 500 nm independently of each other.

The organic thin film layer that does not contain an organic silane compound adopts the same method as the anode and cathode formation method using a predetermined substance, regardless of whether it is a light-emitting layer, an electron transport layer, or a hole transport layer. Can be formed.
Regardless of whether or not it contains an organosilane compound, the thicknesses of the light-emitting layer, the electron transport layer, and the hole transport layer are not particularly limited, and may usually be 1 to 500 nm independently of each other.
The organic thin film layer containing an organosilane compound can be formed by a method shown below using a predetermined substance.

(Organic thin film layer containing organosilane compound and method for forming the same)
The organic thin film layer containing the organosilane compound is bonded to the formation layer via a chemical bond by a method including a solution process, whether it is a light-emitting layer, an electron transport layer, or a hole transport layer. However, it can be formed as an amorphous film. The layer to be formed means a layer on which an organosilane compound-containing layer is to be formed. For example, when the organic silane compound is contained in the light emitting layer in the configuration (1), the layer to be formed indicates an anode. Further, for example, when the organosilane compound is contained in the hole transport layer in the configuration (2), the layer to be formed indicates an anode. Further, for example, in the structures (3) and (4), when the organic transport compound is contained in the electron transport layer, the formation layer indicates a light emitting layer.

  As a thin film forming method including a solution process, a known method such as a chemical adsorption method, an LB method (Langmuir Blodget method), a dipping method, a spin coating method, or a casting method can be employed. Hereinafter, a thin film configuration when an organic thin film is formed using an organosilane compound and a method for forming the thin film will be described.

FIG. 2 is an example of a schematic configuration diagram of an organic thin film formed using an organosilane compound. In FIG. 2, for example, in the general formula (I), ^one of R ^{1 to} R ² is a silyl group, and at least one group out of R ^{3 to} R ⁴ and R ^{9 to} R ¹⁰ is a functional group. When the organosilane compound 13 is used, it is shown that the amorphous thin film 10 is formed on the formation layer 11 while the polycyclic skeleton 12 is bonded through a silanol bond (—Si—O—). Yes. That is, the alkoxy group or halogen atom of the silyl group is converted into an ether bond (—O—) as a result, and the organic silane compound and thus the organic thin film layer 10 containing the compound is formed on the formation layer 11 by the ether bond. Combined. Further, since the intermolecular distance between adjacent molecules is increased due to the steric hindrance of the functional group 13, the intermolecular interaction (van der Waals interaction) between adjacent molecules is reduced. Therefore, as shown in FIG. 2, the compound molecules can be randomly oriented without being crystallized while being regularly arranged, and an amorphous film 10 having excellent conductivity can be obtained.

In FIG. 2, the thin film has a monomolecular layer structure, but such a structure can be formed by, for example, a chemical adsorption method. Specifically, the organosilane compound is dissolved in an organic solvent. The organic silane compound is bonded to the layer to be formed by immersing a substrate including the layer having a hydroxyl group on the surface in the obtained solution for a predetermined time. The details of the mechanism at this time are generally considered that mechanisms A1 and B1 shown below are involved in a complex manner.
Mechanism A1: The alkoxy group or halogen atom of the organic silane compound (silyl group) is hydrolyzed and converted into a hydroxyl group by a water molecule slightly contained in the organic solvent, and between the hydroxyl group and the hydroxyl group of the layer to be formed. Dehydration occurs.
Mechanism B1; a dealcoholization reaction or a dehydrohalogenation reaction occurs between the alkoxy group or halogen atom of the organosilane compound (silyl group) and the hydroxyl group of the formation layer, respectively.
As a result, it is considered that the silicon atom of the silyl group and the layer to be formed are chemically bonded through an ether bond (—O—).
Film formation by such a mechanism can be easily achieved not only by a chemical adsorption method but also by other solution processes such as a spin coating method and a dipping method.

Further, the monomolecular layer structure in FIG. 2 can be easily formed by the LB method. Specifically, the organosilane compound is dissolved in an organic solvent. The obtained solution is dropped on the water surface to form a thin film on the water surface. In this state, pressure is applied on the water surface, and the substrate including the layer having a hydroxyl group on the surface is pulled up to bond the organosilane compound to the layer to be formed. The details of the mechanism at this time are generally considered that the mechanism C1 and the mechanisms A1 and B1 described below are involved in a complex manner.
Mechanism C1: The alkoxy group or halogen atom of the organosilane compound (silyl group) is hydrolyzed and converted into a hydroxyl group by water added dropwise to the solution, and a dehydration reaction occurs between the hydroxyl group and the hydroxyl group of the formation layer. Occur.
As a result, it is considered that the silicon atom of the silyl group and the substrate are chemically bonded via an ether bond (—O—).

As another bonding form, for example, when the layer to be formed has a carboxyl group on the surface, it is considered that the details of the mechanism are generally able to involve mechanisms A2, B2 and C2 shown below in a complex manner.
Mechanism A2: The alkoxy group or halogen atom of the organic silane compound (silyl group) is hydrolyzed and converted into a hydroxyl group by a water molecule slightly contained in the organic solvent, and between the hydroxyl group and the carboxyl group of the layer to be formed. Dehydration reaction occurs.
Mechanism B2: A dealcoholization reaction or a dehalogenation reaction occurs between the alkoxy group or halogen atom of the organosilane compound (silyl group) and the carboxyl group of the layer to be formed, respectively.
Mechanism C2 (in the case of LB method): The alkoxy group or halogen atom of the organosilane compound (silyl group) is hydrolyzed and converted into a hydroxyl group by water in which the solution is dropped, and the hydroxyl group and the carboxyl group of the layer to be formed are converted. A dehydration reaction occurs between them.
As a result, it is considered that the silicon atom of the silyl group and the layer to be formed are chemically bonded via an ester bond [silicon atom side: —O—C (═O) —: substrate side]. In addition, since an ester bond includes an ether bond (—O—) in the structure, in the present invention, an organic silane compound is bonded to a formation layer via an ether bond when bonded via an ester bond. Are also included.

  When the layer to be formed does not have an active hydrogen-containing group such as a hydroxyl group or a carboxyl group on the surface, the active hydrogen-containing group can be imparted to the surface of the layer by hydrophilization treatment. The hydrophilization treatment can be performed, for example, by immersing the formation layer in a mixed solution of hydrogen peroxide and concentrated sulfuric acid.

  In the present invention, various types of bonds as described above may occur in a composite manner between the organosilane compound-containing layer and the layer to be formed.

FIG. 3 is another example of a schematic configuration diagram of an organic thin film formed using an organosilane compound. In FIG. 3, for example, in the general formula (I), ^one of R ^{1 to} R ² is a silyl group, and at least one group out of R ^{3 to} R ⁴ and R ^{9 to} R ¹⁰ is a nitrogen atom or When an organic silane compound that is a functional group 16 having an oxygen atom (for example, a diarylamino group, an alkoxy group, or an oxyaryl group) is used, the polycyclic skeleton 15 is firmly formed on the formation layer 14 via a silanol bond. In addition to being bonded, it is shown that the amorphous organic thin film 20 can have a multi-layer structure by the interaction (hydrogen bond) between the functional group 16 and the silanol group (indicated by a dotted line in FIG. 3). ing. That is, the alkoxy group or halogen atom of the silyl group at the interface with the formation layer 14 is converted to an ether bond (—O—) as a result, and the organic silane compound, and thus the organic containing the compound, via the ether bond. A thin film layer 20 is bonded onto the formation layer 14. On the other hand, the organic silane compound bonded to the formation layer 14 via an ether bond interacts with the hydroxyl group of the silyl group of another organic silane compound in the functional group 16 on the upper side thereof, so that the multimolecular layer It has a structure. At this time, if at least one of X ¹ or X ² in the silyl group is a substituent that does not react with an adjacent molecule, the effect of steric hindrance between the silyl groups is further increased, and a higher quality amorphous film can be formed. Although it can be obtained, considering that the reactivity with the layer to be formed decreases if the molecular volume of the substituent is too large, the substituent is smaller than the molecular volume of the polycyclic skeleton 15 of the main skeleton. Is preferred.

Further, at this time, when at least one of X ¹ or X ² in the silyl group is an alkoxy group or a halogen atom, and the silyl group has 2 to 3 silanol groups as a result, the bond to the substrate in one compound molecule There are 2 to 3 portions, and the adhesion to the layer to be formed can be further enhanced. In this case, it is possible to include many structures in which the polycyclic skeleton stands vertically with respect to the layer to be formed by providing two or three bonding portions with the layer to be formed. In this way, while the polycyclic skeleton is moderately randomly oriented, the π-π interaction between adjacent molecules is moderately strong by giving the polycyclic skeleton a structure that stands perpendicular to the layer to be formed. Therefore, the conductivity of the organic thin film can be further increased. Therefore, the conductivity of the organic thin film is further increased, and as a result, high device characteristics having an organic thin film that can efficiently transport holes or electrons can be realized.

An organic thin film having a multilayer structure as shown in FIG. 3 can be easily formed by, for example, a dipping method, a spin coating method, a casting method, or the like.
Specifically, the organosilane compound is dissolved in an organic solvent. In the obtained solution, a substrate including a formation layer having a hydroxyl group or a carboxyl group on the surface is immersed and pulled up. Alternatively, the obtained solution is applied to the surface of the layer to be formed. Thereafter, the thin film is fixed by washing with an organic solvent, washing with water, and drying by standing or heating. The thin film may be further subjected to treatment such as electrolytic polymerization.

  The organic solvent that can dissolve the organic silane compound when forming the organic thin film varies depending on the functional group and silyl group of the compound, for example, hexane, n-hexadecane, methanol, ethanol, IPA, chloroform, Nonaqueous organic solvents such as dichloromethane, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, THF, dimethyl ether, diethyl ether, DMSO, toluene, xylene, benzene and the like can be mentioned.

  The present invention does not preclude the adoption of methods such as vacuum vapor deposition, molecular beam vapor deposition, and sputtering that have been conventionally employed as a method for forming an organosilane compound-containing layer.

<Synthesis of organosilane compounds>
(Preparation example 1)
2,3,6,7-tetra (trimethylsilyl) naphthalene used in Synthesis Example 1 and Synthesis Example 4 was synthesized by the following method according to the first reaction formula of Route A4 or Route A5.
Specifically, first, in a 200 ml glass flask equipped with a stirrer, a reflux condenser, a thermometer and a dropping funnel, magnesium 0.4M, HMPT (Hexamethyl phosphorous triamide) 100 ml, THF 20 ml and I ₂ (catalyst), 1, 2, After adding 0.1M of 4,5-tetrachlorobenzene (available for example with a purity of 99% from Kishida Chemical), 0.4M of chlorotrimethylsilane was added dropwise at a temperature of 80 ° C and stirred for 30 minutes. Was refluxed for 4 days to synthesize 1,2,4,5-tetra (trimethylsilyl) benzene. Subsequently, i-Pr ₂ NH ₂₀ mM, PhI (OAc) ₂ [(diacetoxyiodo) benzene) 50 mM and dichloromethane 50 mL were added to a 200 mL eggplant flask, and then CF ₃ CO ₂ at 0 ° C. H (T _f OH) 50 mM was added dropwise and stirred for 2 hours. Subsequently, 10 mL of a dichloromethane solution containing 50 mM of 1,2,4,5-tetra (trimethylsilyl) benzene was added dropwise at 0 ° C. and stirred at room temperature for 2 hours, whereby phenyl [2,4,5-tris ( Trimethylsilyl) phenyl] iodonium triflate (phenyl [2,4,5-tris (trimethylsilyl) phenyl] iodonium Triflate) was synthesized. Subsequently, a 50 mL eggplant-shaped flask is charged with a THF solution of Bu4NF2.0M, which contains 5 mM of the phenyl [2,4,5-tris (trimethylsilyl) phenyl] iodonium triflate and 10 mM of 3,4-di (trimethylsilyl) furan. 10 mL of a dichloromethane solution was added dropwise at 0 ° C., and the reaction was allowed to proceed by stirring for 30 minutes. After completion of the reaction, extraction with dichloromethane and water was performed, and purification was performed by column chromatography to synthesize a 1,4-dihydro-1,4-epoxynaphthalene derivative. Thereafter, 10 mL of a THF solution containing 1 mM of lithium iodide and 1 mM of DBU (1,8-diazabicyclo [5.4.0] undec-7-ene) is added to the 1,4-dihydro-1,4-epoxynaphthalene derivative. Charge to a 50 ml glass flask equipped with a stirrer, reflux condenser, thermometer, and dropping funnel, add 1 mM of the 1,4-dihydro-1,4-epoxynaphthalene derivative, and then reflux under nitrogen atmosphere for 3 hours. The reaction was allowed to proceed. After completion of the reaction, extraction and removal of water with MgSO ₄ were performed to synthesize the title 2,3,6,7-tetra (trimethylsilyl) naphthalene.

続いて、前記２，３−ジ（トリメチルシリル）−６，８，９，１１−テトラ（ｔｅｒｔ−ブチル）テトラセン１ｍＭを少量の水及びＰｈＮＭｅ_３Ｆを含むＴＨＦ溶媒に溶解させた後、攪拌することで、６，８，９，１１−テトラ（ｔｅｒｔ−ブチル）テトラセンを合成した。さらに、窒素雰囲気下にて、２００ｍｌナスフラスコに乾燥ＴＨＦ５ｍｌ、前記６，８，９，１１−テトラ（ｔｅｒｔ−ブチル）テトラセンを５ｍＭ、マグネシウムを加えた後、１時間攪拌することにより、グリニヤール試薬を形成したのち、攪拌機、還流冷却器、温度計、滴下ロートを備えた１００ｍｌナスフラスコにクロロトリエトキシシラン５ｍＭ、ＴＨＦ３０ｍｌを仕込み、氷冷したのち、前記グリニヤール試薬を加え、３０℃にて１時間成熟を行った。次いで、反応液を減圧にてろ過し、塩化マグネシウムを除いた後、ろ液からＴＨＦ及び未反応のクロロトリエトキシシランをストリップすることにより標記化合物を１５％の収率で得た。 (Synthesis Example 1)
Synthesis of 3-triethoxysilyl-6,8,9,11-tetra-t-butyltetracene 3-triethoxysilyl-6,8,9,11-tetra-t-butyltetracene follows the route A4 according to 2,3 , 7,8-tetra (trimethylsilyl) -6,9- (tert-butyl) -anthracene, then, according to the route C2, the trimethylsilyl group is deprotected with quaternary ammonium and reacted with a silane compound And synthesized.
More specifically, the synthesis was performed by the following method. First, 2,3,6,7-tetra (trimethylsilyl) naphthalene synthesized in Preparation Example 1 was used as a starting material. The synthesis method was 2,5-di (trimethylsilyl) furan instead of 2,5-di (trimethylsilyl) furan. Except for the use of (tert-butyl) -3,4-di (trimethylsilyl) furan, from 1,2,4,5-tetra (trimethylsilyl) benzene of Preparation Example 1 to 2,3,6,7-tetra 2,3,7,8-tetra (trimethylsilyl) -6,9- (tert-butyl) -anthracene was synthesized by a method similar to the method for synthesizing (trimethylsilyl) naphthalene. Further, except for using 3,4- (tert-butyl) furan instead of 2,5- (tert-butyl) -3,4-di (trimethylsilyl) furan, By applying a method similar to the method of synthesizing 2,3,7,8-tetra (trimethylsilyl) -6,9- (tert-butyl) -anthracene from 6,7-tetra (trimethylsilyl) naphthalene, the following structure 2,3-di (trimethylsilyl) -6,8,9,11-tetra (tert-butyl) tetracene represented by the formula (A) was synthesized.

Subsequently, 1 mM of 2,3-di (trimethylsilyl) -6,8,9,11-tetra (tert-butyl) tetracene is dissolved in a small amount of water and a THF solvent containing PhNMe ₃ F, and then stirred. Thus, 6,8,9,11-tetra (tert-butyl) tetracene was synthesized. Furthermore, in a nitrogen atmosphere, 5 ml of dry THF, 5 mM of 6,8,9,11-tetra (tert-butyl) tetracene and magnesium were added to a 200 ml eggplant flask, and then stirred for 1 hour to obtain a Grignard reagent. After formation, a 100 ml eggplant flask equipped with a stirrer, reflux condenser, thermometer, and dropping funnel was charged with 5 mM chlorotriethoxysilane and 30 ml THF, and after ice cooling, the Grignard reagent was added and matured at 30 ° C. for 1 hour. Went. Then, the reaction solution was filtered under reduced pressure to remove magnesium chloride, and then THF and unreacted chlorotriethoxysilane were stripped from the filtrate to obtain the title compound in a yield of 15%.

When the obtained compound was subjected to infrared absorption measurement, Si—O—C absorption was observed at a wavelength of 1035 cm ⁻¹ . From this, it was confirmed that the obtained compound contains a silyl group. When the ultraviolet-visible absorption spectrum of the chloroform solution containing the compound was measured, absorption was observed at a wavelength of 493 nm. This absorption was attributed to the π → π * transition of the tetracene skeleton contained in the molecule, and it was confirmed that the compound contained the tetracene skeleton.
Furthermore, the nuclear magnetic resonance (NMR) measurement of the compound was performed.
(8.0 ppm to 7.3 ppm) (m) (7H; derived from tetracene skeleton)
(3.9 ppm to 3.7 ppm) (m) (6H; derived from ethyl group of silyl group)
(1.6 ppm to 1.1 ppm) (m)
(45H; derived from methyl group of t-butyl group and silyl group)
From these results, it was confirmed that this compound was 3-triethoxysilyl-6,8,9,11-tetra-t-butyltetracene.

(Synthesis Example 2)
Synthesis of 3-di-t-butylmethoxysilyl-9-diphenylmethylpentacene 3-di-t-butylmethoxysilyl-9-diphenylmethylpentacene was synthesized according to the route D2. That is, after forming a Grignard reagent by reacting chlorodiphenylmethane with an equivalent amount of magnesium, 9-diphenylmethylpentacene was synthesized by gradually adding the Grignard reagent into nitrobenzene containing bromopentacene. Subsequently, 3-bromo-9-diphenylmethylpentacene was formed using NBS and then reacted with H—Si (C (CH ₃ ) ₃ ) ₂ OCH ₃ dissolved in nitrobenzene to produce 3- Di-t-butylmethoxysilyl-9-diphenylmethylpentacene was synthesized.
More specifically, first, a Grignard reagent was formed by adding magnesium into a chloroform solution containing a predetermined amount of chlorodiphenylmethane. Subsequently, 9-diphenylmethylpentacene was formed by slowly adding a chloroform solution of 9-bromopentacene. Subsequently, for example, after bromination of the 9-diphenylmethylpentacene using NBS, a compound brominated at other than the 3-position was removed by extraction to obtain 3-bromo-9-diphenylmethylpentacene. Furthermore, chlorodi (tert-butyl) methoxysilane was dissolved in chloroform, and the solution was reacted by adding it to the chloroform solution containing 3-bromo-9-diphenylmethylpentacene to synthesize the title compound (yield). 10%).

When the obtained compound was subjected to infrared absorption measurement, Si—O—C absorption was observed at a wavelength of 1020 cm ⁻¹ . When the ultraviolet-visible absorption spectrum of the chloroform solution containing the compound was measured, absorption was observed at a wavelength of 605 nm.
Furthermore, the nuclear magnetic resonance (NMR) measurement of the compound was performed.
(8.4 ppm to 8.2 ppm) (m) (2H: derived from pentacene skeleton)
(7.9 ppm to 7.5 ppm) (m)
(20H: derived from benzene ring of pentacene skeleton and diarylalkyl group)
(5.4 ppm to 5.3 ppm) (m) (1H: derived from ethyl group of diphenylethyl group)
(3.6 ppm to 3.5 ppm) (m) (3H: derived from methyl group of silyl group)
(1.5 ppm to 1.2 ppm) (m) (18H: derived from t-Bu group of silyl group)
From these results, it was confirmed that this compound was 3-di-t-butylmethoxysilyl-9-diphenylmethylpentacene.

(Synthesis Example 3)
1,4,8,11-Tetranitro-2-di-t-butylethoxysilyl-pentacene was synthesized by the following method. That is, first, 2,3-di (trichlorosilyl) 6,7-dinitronaphthalene was synthesized from 1,2,4,5-tetrachlorobenzene, and a protecting group such as a trimethylsilyl group was reacted with a nitro group. Then, the title compound was synthesized by sequentially increasing the number of acene skeletons and then deprotecting the protecting group.
Specifically, first, in a 200 ml glass flask equipped with a stirrer, a reflux condenser, a thermometer and a dropping funnel, magnesium 0.4M, HMPT (Hexamethyl phosphorous triamide) 100 ml, THF 20 ml and I ₂ (catalyst), 1, 2, After adding 0.1M of 4,5-tetrabenzene (for example, which can be purchased with a purity of 99% from Kishida Chemical), 0.4M of chlorotrimethylsilane was added dropwise at a temperature of 80 ° C. and stirred for 30 minutes, then 130 ° C. Was refluxed for 4 days to synthesize 1,2,4,5-tetra (trimethylsilyl) benzene. Subsequently, i-PrNH 20 mM, PhI (OAc) ₂ ((diacetoxyiodo) benzene) 50 mM, and dichloromethane 50 mL were added to a 200 mL eggplant flask, and then CF ₃ CO ₂ H (T _f OH) 50 mM was added dropwise at 0 ° C. Stir for 2 hours. Subsequently, 10 mL of a dichloromethane solution containing 50 mM of 1,2,4,5-tetra (trimethylsilyl) benzene was added dropwise at 0 ° C. and stirred at room temperature for 2 hours, whereby phenyl [2,4,5-tris ( trimethylsilyl) phenyl] iodonium Triflate was synthesized. Subsequently, a 50 mL eggplant-shaped flask was charged with a THF solution of Bu ₄ NF 2.0M, and 10 mL of a dichloromethane solution containing 5 mM of the above phenyl [2,4,5-tris (trimethylsilyl) phenyl] iodonium Triflate and 10 mM of 3,4-dinitrofuran. Was added dropwise at 0 ° C., and the reaction was allowed to proceed by stirring for 30 minutes. After completion of the reaction, extraction with dichloromethane and water was performed, and purification was performed by column chromatography to synthesize a 1,4-dihydro-1,4-epoxynaphthalene derivative. Thereafter, 10 mL of a THF solution containing 1 mM of lithium iodide and 1 mM of DBU (1,8-diazabicyclo [5.4.0] undec-7-ene) was added to the 1,4-dihydro-1,4-epoxynaphthalene derivative as a stirrer. In a 50 ml glass flask equipped with a reflux condenser, a thermometer, and a dropping funnel, and after adding 1 mM of the 1,4-dihydro-1,4-epoxynaphthalene derivative, the mixture was refluxed for 3 hours under a nitrogen atmosphere. The reaction was allowed to proceed. After completion of the reaction, extraction and removal of water with MgSO ₄ were performed to synthesize 2,3-di (trichlorosilyl) 6,7-dinitronaphthalene. Subsequently, instead of using 3,4-dinitrofuran, the above 1,2,4,5-tetra (trimethylsilyl) benzene was replaced with 2,3 except that 3,4-di (trimethylsilyl) furan was used. -3- (Trimethylsilyl) 7,10-dinitrotetracene was synthesized by applying twice the same method as that for synthesizing -di (trimethylsilyl) 6,7-dinitronaphthalene. Further, instead of using 3,4-dinitrofuran, the above 1,2,4,5-tetra (trimethylsilyl) benzene is used except that 3- (trimethylsilyl) 4- (oxytrimethylsilyl) furan is used. A method similar to the method for synthesizing 2,3-di (trimethylsilyl) 6,7-dinitronaphthalene from the compound was applied once to give 2- (oxytrimethylsilyl) 3- (trimethylsilyl) 1,4,8,11-tetranitro. After synthesizing pentacene, 1 mM of 2- (oxytrimethylsilyl) 3- (trimethylsilyl) 1,4,8,11-tetranitropentacene is dissolved in a THF solvent containing a small amount of water and PhNMe ₃ F, and then stirred. Thus, 2-hydroxy 1,4,8,11-tetranitropentacene was synthesized. Furthermore, in a 100 ml eggplant flask equipped with a stirrer, a reflux condenser, a thermometer, and a dropping funnel, 5 mM of hydrogenated di (tert-butyl) ethoxysilane and 30 ml of THF were charged in a nitrogen atmosphere, and after ice cooling, 5 ml of dry THF, By adding 5 mM of 2-hydroxy 1,4,8,11-tetranitropentacene and ripening at 30 ° C. for 1 hour, the title 1,4,8,11-tetranitro-2-di-t-butyl was obtained. Ethoxysilyl-pentacene was synthesized.

When the obtained compound was subjected to infrared absorption measurement, Si—O—C absorption was observed at a wavelength of 1035 cm ⁻¹ . When the ultraviolet-visible absorption spectrum of the chloroform solution containing the compound was measured, absorption was observed at a wavelength of 605 nm.
Furthermore, the nuclear magnetic resonance (NMR) measurement of the compound was performed.
(8.1 ppm to 8.0 ppm) (s) (1H: derived from pentacene)
(7.9 ppm to 7.8 ppm) (m) (8H: derived from pentacene)
(3.6 ppm to 3.5 ppm) (m) (6H: derived from ethyl of silyl group)
(1.4 ppm to 1.3 ppm) (m)
(27H: derived from t-Bu group and methyl group of silyl group)
From these results, it was confirmed that this compound was 1,4,8,11-tetranitro-2-di-t-butylethoxysilyl-pentacene.

次いで、前記ルートＣ３に従って、トリメチルシリル基を４級アンモニウムを用いて脱保護させ、シラン化合物と反応させることによって、２，３−ジ（ジ−ｔ−ブチルメトキシシリル）−６，８，１１，１３−テトラ（Ｎ，Ｎ−ジフェニルアミノ）ペンタセンを形成した。
より詳細には、合成例１と同様に以下の手法により合成した。まず、前記準備例１で合成した２，３，６，７−テトラ（トリメチルシリル）ナフタレンを出発原料として使用し、合成手法は、３，４−ジ（トリメチルシリル）フランの代わりに、２，５−（Ｎ，Ｎ−ジフェニルアミノ）−３，４−ジ（トリメチルシリル）フランを使用することを除き、準備例１の、１，２，４，５−テトラ（トリメチルシリル）ベンゼンから２，３，６，７−テトラ（トリメチルシリル）ナフタレンを合成する手法と同様の手法にて２，３，７，８−テトラ（トリメチルシリル）−６，９−（Ｎ，Ｎ−ジフェニルアミノ）−アントラセンを合成した。さらに、２，５−（Ｎ，Ｎ−ジフェニルアミノ）−３，４−ジ（トリメチルシリル）フランの代わりに、フランを使用することを除き、本合成例の２，３，６，７−テトラ（トリメチルシリル）ナフタレンから２，３，７，８−テトラ（トリメチルシリル）−６，９−（Ｎ，Ｎ−ジフェニルアミノ）−アントラセンを合成する手法と同様の手法を適用することで、２，３−ジ（トリメチルシリル）ー６，１１−（Ｎ，Ｎ−ジフェニルアミノ）テトラセンを合成した後、さらに、本合成例の２，３，６，７−テトラ（トリメチルシリル）ナフタレンから２，３，７，８−テトラ（トリメチルシリル）−６，９−（Ｎ，Ｎ−ジフェニルアミノ）−アントラセンを合成する手法と同様の手法を再度適用することより、上記構造式（Ｂ）にて表される２，３，９．１０ーテトラ（トリメチルシリル）−６，８，１１，１３−テトラ（Ｎ，Ｎ−ジフェニルアミノ）ペンタセンを合成した。続いて、前記２，３，９．１０ーテトラ（トリメチルシリル）−６，８，１１，１３−テトラ（Ｎ，Ｎ−ジフェニルアミノ）ペンタセン１ｍＭを少量の水及びＰｈＮＭｅ_３Ｆを含むＴＨＦ溶媒に溶解させた後、攪拌することで、６，８，１１，１３−テトラ（Ｎ，Ｎ−ジフェニルアミノ）ペンタセンを合成した。さらに、窒素雰囲気下にて、２００ｍｌナスフラスコに乾燥ＴＨＦ５ｍｌ、前記６，８，１１，１３−テトラ（Ｎ，Ｎ−ジフェニルアミノ）ペンタセンを５ｍＭ、マグネシウムを加えた後、１時間攪拌することにより、グリニヤール試薬を形成したのち、攪拌機、還流冷却器、温度計、滴下ロートを備えた１００ｍｌナスフラスコにクロロ−ジ（ｔｅｒｔ−ブチル）メトキシシラン５ｍＭ、ＴＨＦ３０ｍｌを仕込み、氷冷したのち、前記グリニヤール試薬を加え、３０℃にて１時間成熟を行った。次いで、反応液を減圧にてろ過し、塩化マグネシウムを除いた後、ろ液からＴＨＦ及び未反応のクロロジ（ｔｅｒｔ−ブチル）メトキシシランをストリップすることにより標記化合物を１０％の収率で得た。 (Synthesis Example 4)
Synthesis of 2,3-di (di-t-butylmethoxysilyl) -6,8,11,13-tetra (N, N-diphenylamino) pentacene 2,3-di (di-t-butylmethoxysilyl)- 6,8,11,13-tetra (N, N-diphenylamino) pentacene was synthesized by the following method. First, Intermediate B was synthesized according to the route A5 using 1,2,4,5-tetrachlorobenzene as a starting material.

Next, according to the route C3, the trimethylsilyl group is deprotected with quaternary ammonium and reacted with a silane compound, whereby 2,3-di (di-t-butylmethoxysilyl) -6,8,11,13. -Tetra (N, N-diphenylamino) pentacene was formed.
More specifically, the synthesis was performed in the same manner as in Synthesis Example 1 by the following method. First, 2,3,6,7-tetra (trimethylsilyl) naphthalene synthesized in Preparation Example 1 was used as a starting material. The synthesis method was 2,5-di (trimethylsilyl) furan instead of 2,5-di (trimethylsilyl) furan. Except for the use of (N, N-diphenylamino) -3,4-di (trimethylsilyl) furan, 1,2,4,5-tetra (trimethylsilyl) benzene from Preparation Example 1, 2,3,6, 2,3,7,8-tetra (trimethylsilyl) -6,9- (N, N-diphenylamino) -anthracene was synthesized in the same manner as the method for synthesizing 7-tetra (trimethylsilyl) naphthalene. Furthermore, the 2,3,6,7-tetra (in this synthesis example) was used except that furan was used instead of 2,5- (N, N-diphenylamino) -3,4-di (trimethylsilyl) furan. By applying a similar method to the synthesis of 2,3,7,8-tetra (trimethylsilyl) -6,9- (N, N-diphenylamino) -anthracene from trimethylsilyl) naphthalene, 2,3-di- After synthesizing (trimethylsilyl) -6,11- (N, N-diphenylamino) tetracene, the 2,3,6,7-tetra (trimethylsilyl) naphthalene of this synthesis example was further 2,3,7,8- By reapplying a method similar to the method of synthesizing tetra (trimethylsilyl) -6,9- (N, N-diphenylamino) -anthracene, it is represented by the above structural formula (B). It was synthesized 3,9.10 Tetora (trimethylsilyl) -6,8,11,13- tetra (N, N-diphenylamino) pentacene. Subsequently, 1 mM of 2,3,9.10-tetra (trimethylsilyl) -6,8,11,13-tetra (N, N-diphenylamino) pentacene was dissolved in a small amount of water and a THF solvent containing PhNMe ₃ F. Then, 6,8,11,13-tetra (N, N-diphenylamino) pentacene was synthesized by stirring. Furthermore, under a nitrogen atmosphere, 5 ml of dry THF, 5 mM of the 6,8,11,13-tetra (N, N-diphenylamino) pentacene and magnesium were added to a 200 ml eggplant flask, and then stirred for 1 hour. After forming a Grignard reagent, a 100 ml eggplant flask equipped with a stirrer, a reflux condenser, a thermometer, and a dropping funnel was charged with 5 mM chloro-di (tert-butyl) methoxysilane and 30 ml of THF, and after ice cooling, the Grignard reagent was added. In addition, maturation was performed at 30 ° C. for 1 hour. Then, the reaction solution was filtered under reduced pressure to remove magnesium chloride, and then the title compound was obtained in a yield of 10% by stripping THF and unreacted chlorodi (tert-butyl) methoxysilane from the filtrate. .

When the obtained compound was subjected to infrared absorption measurement, Si—O—C absorption was observed at a wavelength of 1025 cm ⁻¹ . When the ultraviolet-visible absorption spectrum of the chloroform solution containing the compound was measured, absorption was observed at a wavelength of 615 nm.
Furthermore, the nuclear magnetic resonance (NMR) measurement of the compound was performed.
(8.2 ppm) (s) (2H: derived from pentacene)
(8.0 ppm to 7.9 ppm) (m) (6H: derived from pentacene)
(7.2 ppm to 7.0 ppm) (m) (16H: derived from diphenylamino group)
(6.8 ppm to 6.3 ppm) (m) (24H: derived from diphenylamino group)
(3.6 ppm to 3.5 ppm) (m) (6H: derived from methoxy group of silyl group)
(1.4 ppm to 1.3 ppm) (m) (36H: derived from t-Bu group of silyl group)
From these results, it was confirmed that this compound was 2,3-di (di-t-butylmethoxysilyl) -6,8,11,13-tetra (N, N-diphenylamino) pentacene.

<Manufacture of organic EL elements>
Example 1
First, the glass substrate was ultrasonically cleaned in an organic solvent (for example, acetone or isopropyl alcohol), and then plasma ashing was performed at 100 W for 5 minutes. Subsequently, an ITO transparent electrode thin film having a thickness of 150 nm was formed on this substrate by RF sputtering and patterned. In this state, it was introduced into a vacuum deposition apparatus, the inside of the tank was depressurized to 5.0 × 10 ⁻⁶ Torr, TPD was deposited on the ITO transparent electrode as a hole transport layer with a thickness of 50 nm, and Alq3 was further deposited as a light emitting layer. Vapor deposited on the hole transport layer with a thickness of 50 nm. Subsequently, the substrate was immersed in a solution of hydrogen peroxide: sulfuric acid = 1: 4 for 15 minutes to hydrophilize the surface. On the other hand, 3-di-t-butylmethoxysilyl-9-diphenylmethylpentacene obtained in Synthesis Example 2 was dissolved in a chloroform solvent to prepare a 2 mM sample solution, and subsequently on the water surface in the trough, A predetermined amount (100 μl) of a sample solution was dropped to form a monomolecular film (L film) of the compound on the water surface. In this state, pressure is applied on the water surface to obtain a predetermined surface pressure (30 mN / cm ² ), and then the substrate laminated up to the previously set light emitting layer is pulled up at a constant speed, whereby electrons are formed on the light emitting layer. A transport layer was formed. Furthermore, MgAg was vapor-deposited on the electron transport layer as a cathode with a thickness of 200 nm, thereby manufacturing an organic EL device.
The organic EL device constructed in this way has a high electron transport efficiency, especially because the interface between the light-emitting layer and the electron transport layer is firmly bonded via a chemical bond, and thus the drive voltage can be reduced. It is. The constructed organic EL device was confirmed to have a maximum emission of 3500 cd / m ² at an applied voltage of 11.5V.

(Example 2)
First, the glass substrate was ultrasonically cleaned in an organic solvent (for example, acetone or isopropyl alcohol), and then plasma ashing was performed at 100 W for 5 minutes. Subsequently, an ITO transparent electrode thin film having a thickness of 150 nm was formed on this substrate by RF sputtering and patterned. Subsequently, the substrate was dipped in a solution of hydrogen peroxide: sulfuric acid = 7: 3 for 15 minutes to hydrophilize the surface. On the other hand, a 1,4,8,11-tetranitro-2-di-t-butylethoxysilyl-pentacene obtained in Synthesis Example 3 was dissolved in a chloroform solvent to prepare a 2 mM sample solution, A hole transport layer was formed on the anode by immersing the laminated substrate. In this state, it was introduced into a vacuum deposition apparatus, and the inside of the tank was depressurized to 7.0 × 10 ⁻⁶ Torr, and then Alq3 was deposited as a light emitting layer on the hole transport layer with a thickness of 50 nm. Furthermore, an organic EL element was manufactured by evaporating MgAg as a cathode with a thickness of 200 nm on the hole transport layer.
The organic EL device constructed in this way has a high hole transport efficiency or electron transport efficiency, particularly because the interface between the anode and the hole transport layer is firmly bonded via a chemical bond. It can be made smaller. The constructed organic EL device was confirmed to have a maximum emission of 3300 cd / m ² at an applied voltage of 12.0V.

(Example 3)
First, the glass substrate was ultrasonically cleaned in an organic solvent (for example, acetone or isopropyl alcohol), and then plasma ashing was performed at 100 W for 5 minutes. Subsequently, an ITO transparent electrode thin film having a thickness of 100 nm was formed on this substrate by RF sputtering and patterned. In this state, it was introduced into a vacuum deposition apparatus, the inside of the tank was depressurized to 5.0 × 10 ⁻⁶ Torr, TPD was deposited on the ITO transparent electrode as a hole transport layer with a thickness of 50 nm, and Alq3 was further deposited as a light emitting layer. Vapor deposited on the hole transport layer with a thickness of 50 nm. Subsequently, the substrate was immersed in a solution of hydrogen peroxide: sulfuric acid = 1: 4 for 15 minutes to hydrophilize the surface. On the other hand, 2,3-di (di-t-butylmethoxysilyl) -6,8,11,13-tetra (N, N-diphenylamino) pentacene obtained in Synthesis Example 4 was dissolved in a chloroform solvent to obtain 2 mM. Then, a predetermined amount (100 μl) of the sample solution was dropped on the water surface in the trough to form the compound monomolecular film (L film) on the water surface. In this state, pressure is applied on the water surface to obtain a predetermined surface pressure (25 mN / cm ² ), and then the substrate laminated up to the previously set light emitting layer is pulled up at a constant speed, whereby electrons are formed on the light emitting layer. A transport layer was formed. Furthermore, MgAg was vapor-deposited on the electron carrying layer with a thickness of 100 nm as a cathode, and the organic EL element was manufactured.
The organic EL device constructed in this way has a high electron transport efficiency, especially because the interface between the light-emitting layer and the electron transport layer is firmly bonded via a chemical bond, and thus the drive voltage can be reduced. It is. The constructed organic EL device was confirmed to have a maximum emission of 4500 cd / m ² at an applied voltage of 10.5V.

(Comparative Example 1)
First, the glass substrate was ultrasonically cleaned in an organic solvent (for example, acetone or isopropyl alcohol), and then plasma ashing was performed at 100 W for 5 minutes. Subsequently, an ITO transparent electrode thin film having a thickness of 100 nm was formed on this substrate by RF sputtering and patterned. In this state, it was introduced into a vacuum deposition apparatus, and the inside of the tank was depressurized to 5.0 × 10 ⁻⁶ Torr, and then TPD was deposited on the ITO transparent electrode as a hole transport layer with a thickness of 50 nm, and further as a light emitting layer Alq3 was deposited on the hole transport layer with a thickness of 50 nm. Subsequently, 6,8,11,13-tetra (N, N-diphenylamino) pentacene, which is an intermediate of Synthesis Example 4, was formed as an electron transport layer on the light emitting layer by vacuum deposition. Furthermore, MgAg was vapor-deposited on the electron carrying layer with a thickness of 100 nm as a cathode, and the organic EL element was manufactured.
The organic EL device constructed in this manner could not confirm light emission of 1000 Cd or more in the range up to an applied voltage of 15.0V.
In this comparative example, the reason is that the light-emitting layer and the electron transport layer are bonded through physical adsorption, and the electron transfer is inefficient. That is, as in the organic EL device of the present invention, it has been confirmed that high luminous efficiency can be obtained at a low applied voltage when a chemical bond is interposed between layers.

It is a schematic block diagram which shows an example of the organic EL element of this invention. It is a conceptual diagram of the molecular level of the organosilane compound content layer used for the organic EL element of this invention. It is a conceptual diagram of the molecular level of the organosilane compound content layer used for the organic EL element of this invention.

Explanation of symbols

1: Anode, 2: Hole transport layer, 3: Light emitting layer, 4: Electron transport layer, 5: Cathode, 6: Substrate, 11:14: Layer to be formed (layer on which the organosilane compound-containing layer is to be formed) 12:15: polycyclic fused aromatic hydrocarbon skeleton (polycyclic skeleton), 13: functional group, 16: functional group (containing nitrogen atom or oxygen atom).

Claims (5)

Having one or more organic thin film layers between an anode and a cathode, wherein at least one organic thin film layer has the general formula (I);

[Wherein, m is an integer of 2 to 8; at least one group of R ^{1 to} R ¹⁰ is represented by the general formula —SiX ¹ X ² X ³ (at least one group of X ^{1 to} X ³ is A group that gives a hydroxyl group by hydrolysis or a halogen atom, and other groups are groups that do not react with neighboring molecules), and at least one group is electron-donating or electron-withdrawing a sexual functional groups, other groups are hydrogen atom; provided ^that at least one of R 1 to R ² is a silyl group, and at least one of ^R 3 to R ⁴ and ^R 9 ^{to R 10} An organic electroluminescent device comprising an organic silane compound represented by the formula: wherein the group is a functional group, and is bonded to an anode, a cathode, or another organic thin film layer through a chemical bond. Having one or more organic thin film layers between an anode and a cathode, wherein at least one organic thin film layer has the general formula (I);

[Wherein, m is an integer of 2 to 8; at least one group of R ^{1 to} R ¹⁰ is represented by the general formula —SiX ¹ X ² X ³ ( at least one group of X ^{1 to} X ³ is A group that gives a hydroxyl group by hydrolysis or a halogen atom, and other groups are groups that do not react with neighboring molecules), and at least one group is electron-donating or electron-withdrawing Functional group and other group is a hydrogen atom], and an organic electroluminescent device bonded to an anode, a cathode or other organic thin film layer through a chemical bond The structure having one or more organic thin film layers between the anode and the cathode is anode-light-emitting layer-electron transport layer-cathode structure or anode-hole transport layer-light-emitting layer-electron transport layer. The cathode configuration, the electron transport layer Serial general formula includes an organic silane compound represented by the formula (I), organic electroluminescent elements characterized in that it is combined with the light emitting layer via a chemical bond.   The structure having one or more organic thin film layers between the anode and the cathode is an anode-hole transport layer-light-emitting layer-cathode structure or anode-hole transport layer-light-emitting layer-electron transport layer-cathode. 2. The organic electroluminescence device according to claim 1, wherein the hole transport layer contains an organosilane compound represented by the general formula (I) and is bonded to the anode through a chemical bond. .   The group that does not react with the adjacent molecule that the silyl group may have is a substituted or unsubstituted alkyl group, cycloalkyl group, aryl group, diarylamino group, or di- or triarylalkyl group The organic electroluminescence in any one of Claims 1-3. R ³ is R ⁴ , R ⁵ is R ⁶ , R ⁷ is R ⁸ , and R ⁹ is R ¹⁰ , respectively. Organic electroluminescence.

Images