JP2019160420A - Method for controlling conductivity of charge transport layer, organic electronics element, and organic electroluminescence element and usage thereof - Google Patents

Abstract

To provide a method for controlling conductivity of a charge transport layer in forming a charge transport layer by a wet type process.SOLUTION: The method, which is a method for controlling conductivity of a charge transport layer, includes forming of a charge transport layer, using a charge transport material containing at least two types of polymerizable charge transport polymer.SELECTED DRAWING: None

Description

  The present disclosure relates to a method for controlling the conductivity of a charge transport layer. The present disclosure also relates to an organic electronics element, an organic electroluminescence element (also referred to as an “organic EL element”), a display element, a lighting device, and a display device.

  Organic EL devices are attracting attention as large-area solid-state light source applications as alternatives to, for example, incandescent lamps and gas-filled lamps. It is also attracting attention as the most powerful self-luminous display that can replace the liquid crystal display (LCD) in the flat panel display (FPD) field, and its commercialization is progressing.

  Organic EL elements are roughly classified into two types, ie, low molecular organic EL elements using low molecular compounds and high molecular organic EL elements using high molecular compounds, depending on the organic materials used. The manufacturing method of the organic EL element includes a dry process in which film formation is mainly performed in a vacuum system and a wet process in which film formation is performed by plate printing such as letterpress printing and intaglio printing, and plateless printing such as inkjet. It is roughly divided into two. Since simple film formation is possible, the wet process is expected as an indispensable method for future large-screen organic EL displays (see, for example, Patent Document 1).

On the other hand, further improvements are desired for various characteristics such as the luminous efficiency of the organic EL element. Attempts have been made to increase the performance of organic EL elements by dividing the organic layer into multiple layers and separating the functions of each layer. In the case of multilayering according to a wet process, solvent resistance of the lower layer with respect to the coating solution used at the time of film formation of the upper layer is required.
As a multilayering method, for example, there is a method of using two kinds of compounds having different solubility in water and an organic solvent as materials constituting adjacent layers. More specifically, water-soluble PEDOT: PSS is used as a compound for forming a lower layer such as a buffer layer or a hole injection layer. On the other hand, a material that is soluble in an organic solvent such as toluene is used as a compound that forms an upper layer such as a photoelectric conversion layer or a light emitting layer. Since the lower layer formed by PEDOT: PSS is insoluble in an organic solvent such as toluene, a two-layer structure can be produced by a coating method. However, in the above method, moisture tends to remain in the organic layer, and the characteristics of the organic layer tend to deteriorate. In addition, there is a limit to the materials that can be used for multilayering.

  As another method of multilayering, there is a method in which the organic layer is insolubilized by stimulation with heat, light or the like after film formation in order to improve the solvent resistance of the lower organic layer (for example, Patent Document 2). For example, after forming an organic layer using a polymer having a polymerizable functional group, it is possible to improve the solvent resistance by curing the organic layer by heating.

JP 2006-279007 A JP 2013-181103 A

Use of a polymer having a polymerizable functional group is effective from the viewpoint of multilayering an organic layer by a wet process. However, it cannot be said that the various characteristics of the organic EL device using the polymer are sufficiently satisfactory, and further improvement is required.
Typically, an organic EL element includes a light emitting layer and a plurality of charge transport layers such as a hole transport layer and an electron transport layer provided so as to sandwich the light emitting layer. Usually, the physical property value of the charge transport layer is adjusted according to the performance of the light emitting layer.
Among them, the charge balance in the light emitting layer is important because it becomes a factor that affects the device life, the light emitting efficiency, and the light emitting position in the light emitting layer. The charge balance means the ratio of holes and electrons transported from the positive electrode and negative electrode sides to the light emitting layer. In the organic EL element, light emission can be obtained by recombination of holes and electrons transported to the light emitting layer. Therefore, if the charge balance is biased to one of the charges, the characteristics of the organic EL element are significantly deteriorated. Become.
Therefore, in order to improve the performance of the organic EL element, it is required to control the conductivity of each charge transport layer and optimize the charge balance.

The conductivity of the charge transport layer formed by the wet process can be determined, for example, by configuring the polymer forming the charge transport layer using two or more monomer compounds and changing the compounding ratio of the monomer compounds. Or by using two or more kinds of polymers in combination. However, in practice, the range in which the conductivity can be adjusted is limited by the characteristics of the monomer compound used and the blending ratio thereof, and when the polymer is used in combination, the characteristics greatly change due to the influence of compatibility and the like. Therefore, it cannot be said that any method can efficiently control the conductivity. Therefore, a method for easily and efficiently controlling the conductivity of the charge transport layer formed by a wet process is desired.
Therefore, in view of the above, the present disclosure provides a method capable of easily controlling the conductivity of the charge transport layer in forming the charge transport layer by a wet process. Further, the present disclosure provides an organic electronics element, an organic EL element, a display element, a lighting device, and a display device having excellent characteristics by appropriately controlling the conductivity of the charge transport layer formed by a wet process. Make provision possible.

The present inventors have intensively studied the conductivity of the charge transport layer formed by a wet process, and by using two or more kinds of polymerizable charge transport polymers in combination, the conductivity of the organic layer can be easily increased. The inventors have found that control is possible, and have completed the present invention. That is, although the embodiment of the present invention relates to the following, the present invention is not limited to the following embodiment, and includes various embodiments.
One embodiment is a method of controlling the conductivity of a charge transport layer, comprising forming the charge transport layer with a charge transport material containing two or more polymerizable charge transport polymers. About.

  In one embodiment of the method, the charge transporting polymer comprises a first charge transporting polymer having at least one first polymerizable functional group at a terminal and at least one second polymerizable functional group at a terminal. And the second charge transporting polymer having a charge transporting ability different from that of the first charge transporting polymer, wherein the first polymerizable functional group and the second polymerizable functional group are It is preferred that a bond can be formed.

  In one embodiment of the method, the first polymerizable functional group and the second polymerizable functional group preferably have different structures.

  In one embodiment of the method, it is preferable that the first polymerizable functional group is a conjugated diene and the second polymerizable functional group is a dienophile.

  In one embodiment of the method, the charge transporting material further contains a polymerization initiator, and the first polymerizable functional group and the second polymerizable functional group are each a three-membered ring or more. It preferably contains a cyclic ether group.

  In one embodiment of the method, the two or more polymerizable charge transporting polymers are each independently a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, benzene structure, and fluorene structure. It is preferable to include at least one structure selected from the group consisting of

  In one embodiment of the above method, the charge transporting material is preferably used as a hole injecting material or a hole transporting material.

  In one embodiment of the method, the charge transport layer is preferably formed using an ink composition containing the charge transport material and a solvent.

  In another embodiment, a charge transporting layer formed by using a charge transporting material containing two or more polymerizable charge transporting polymers or an ink composition containing the charge transporting material and a solvent is provided. Including an organic electronics element.

  In another embodiment, a charge transporting layer formed by using a charge transporting material containing two or more polymerizable charge transporting polymers or an ink composition containing the charge transporting material and a solvent is provided. Including an organic electroluminescent element.

  In embodiment of the said organic electroluminescent element, it is preferable to further have a flexible substrate. The flexible substrate preferably includes a resin film.

  Other embodiment is related with the display element provided with the organic electroluminescent element of the said embodiment.

  Other embodiment is related with the illuminating device provided with the organic electroluminescent element of the said embodiment.

  Other embodiment is related with the illuminating device of the said embodiment, and the display apparatus provided with the liquid crystal element as a display means.

  According to the present disclosure, it is possible to provide a method capable of controlling the conductivity of the charge transport layer in forming the charge transport layer by a wet process. In addition, according to the above method, since the conductivity of the charge transport layer can be controlled, it is easy to provide an organic electronics element, an organic EL element, a display element, a lighting device, and a display device having excellent characteristics. .

FIG. 1 is a schematic cross-sectional view showing an embodiment of an organic EL element. FIG. 2 is a graph showing the relationship between the charge transporting polymer blending ratio and current density in Example 1 and Comparative Examples 1 and 2. FIG. 3 is a graph showing the relationship between the charge transporting polymer blending ratio and the current density in Examples 2-1 to 2-3. FIG. 4 is a graph showing the relationship between the charge transport polymer blending ratio and the current density in Examples 3 to 5.

  Hereinafter, although embodiment of this invention is described, this invention is not limited to embodiment described below.

One embodiment relates to a method for controlling the conductivity of a charge transport layer, the method comprising forming a charge transport layer using a charge transport material comprising two or more polymerizable charge transport polymers. Including. Here, “two or more kinds of polymerizable charge transporting polymers” means two or more kinds of charge transporting polymers each having one or more polymerizable functional groups in the molecule and different charge transporting capabilities. Means a combination of
Among the combinations of two or more kinds of charge transporting polymers each having different charge transporting ability in terms of the material constituting the charge transporting layer, two or more kinds of charge transporting polymers having mutually polymerizable functional groups as described above In this combination, the conductivity of the charge transport layer can be easily controlled by adjusting the blending ratio of each charge transport polymer. On the other hand, when the charge transporting polymers do not have polymerizable functional groups, it is difficult to obtain the desired conductivity of the charge transporting layer in comparison with the combination of charge transporting polymers having polymerizable functional groups. In addition, the conductivity itself tends to decrease.

In general, in a polymer blend, characteristics are greatly changed depending on various factors such as compatibility between two or more kinds of polymers used in combination, and thus it is difficult to predict the obtained characteristics. In particular, in a charge transport layer formed by combining two or more kinds of charge transporting polymers not having a polymerizable functional group, a bond is not formed between the charge transporting polymers, and it is considered that charges are transferred by hopping conduction.
On the other hand, in the charge transport layer formed by combining the charge transport polymers having a polymerizable functional group capable of forming a bond between the charge transport polymers as described above, the interaction between the polymers is likely to occur. Therefore, it is considered that charges are transferred by intramolecular conduction.
From the viewpoint of conductivity, intramolecular conduction is preferable to hopping conduction, and in intramolecular conduction, carriers in the charge transport layer move through each charge transport polymer equally. Therefore, it is considered that in the combination of two or more kinds of polymerizable charge transporting polymers, the conductivity can be easily controlled by adjusting the blending ratio of the polymers. Further, it is considered that the conductivity of the charge transport layer can be adjusted in a wide range by combining charge transport polymers having various charge transport capabilities. Hereinafter, the charge transport material forming the charge transport layer will be described more specifically.

<Charge transport material>
The charge transport material includes at least two charge transport polymers that have the ability to transport charge and are polymerizable. More specifically, the charge transporting material contains two or more kinds of charge transporting polymers each having one or more polymerizable functional groups in the molecule and having different ability to transport charges to each other (charge transporting ability). .

  Here, the “polymerizable functional group” means a functional group that can form a bond by applying at least one of heat and light. When the charge transporting polymer has at least one polymerizable functional group in the molecule, it becomes easy to change the solubility in the solvent after the polymerization reaction. The polymerization mechanism in which the polymerizable functional group functions is not particularly limited, and is a pericyclic reaction such as a cationic polymerization reaction, an anionic polymerization reaction, a radical polymerization reaction, an addition polymerization reaction, a Diels-Alder reaction that occurs between a conjugated diene and a dienophile, and Any of the trimerization cyclization reaction by alkyne may be sufficient.

  Further, “two or more types of charge transporting polymers having different charge transporting ability” means that the structural units constituting the main skeleton of the polymer are more specifically different. In one embodiment, it means that the combination of two or more structural units is different, or even in the same combination, the blending ratio is different.

In one embodiment, the charge transport material has a first charge transport polymer having at least one first polymerizable functional group at a terminal and at least one second polymerizable functional group at a terminal; And a second charge transporting polymer having a charge transporting ability different from that of the first charge transporting polymer, wherein the first polymerizable functional group and the second polymerizable functional group form a bond with each other. It is preferable to have a structure to obtain. According to the above-described embodiment, the polymerization reaction between the charge transporting polymers easily proceeds and bonds can be formed by the reaction, so that the charge transport layer can be formed more easily than the mixture in which no bond is formed between the polymers. It is considered that the conductivity can be easily controlled.
In the present specification, the term “polymer” includes “oligomer” indicating a polymer having a low degree of polymerization. In one embodiment, the charge transporting material can be preferably used as an organic electronic material.

The first polymerizable functional group and the second polymerizable functional group may have essentially the same structure or different structures. Here, “essentially the same structure” means that the main structures are the same, but different structures or the like in the substituents may be used.
In one embodiment, the first polymerizable functional group and the second polymerizable functional group are each independently a group having a carbon-carbon multiple bond, a group having a small ring, a cyclic ether group, and an aromatic group. It may be at least one selected from the group consisting of groups having a heterocyclic ring.

More specifically, the group having a carbon-carbon multiple bond may be a carbon-carbon double bond-containing group or a carbon-carbon triple bond (alkyne) -containing group, and the carbon-carbon double bond-containing group is More preferred. Specific examples of the carbon-carbon double bond-containing group include vinyl group, allyl group, butenyl group, ethynyl group, acryloyl group, acryloyloxy group, acryloylamino group, methacryloyl group, methacryloyloxy group, methacryloylamino group, vinyloxy group, And vinylamino groups.
Specific examples of the group having a small ring include cyclic alkyl groups such as cyclopropyl group and cyclobutyl group.
The cyclic ether group may be a cyclic ether group having 3 or more members, and specific examples thereof include an epoxy group and an oxetane group.
Specific examples of the group having an aromatic heterocycle include a furan-yl group, a pyrrole-yl group, a thiophene-yl group, and a siloleoyl group.
Each group exemplified as the polymerizable functional group may be unsubstituted or may have a substituent.

In one embodiment, the first polymerizable functional group and the second polymerizable functional group are each independently an epoxy group, an oxetane group, a vinyl group, an acrylate, from the viewpoint of reactivity and characteristics of the organic electronic device. It is preferably at least one selected from the group consisting of a group, a methacrylate group, a furan-yl group, a pyrrole-yl group, and a thiophene-yl group.
Each of the polymerizable functional groups does not need to have a single structure, and may be a combination of two or more as long as a bond is formed.

  In general, polymerization of a polymer having a cyclic ether group such as an oxetane group and an epoxy group is carried out in such a way that an active species generated from a polymerization initiator upon heating or an oxetane group or an epoxy group opened by this active species is not opened. It proceeds by attacking and adding oxetane groups or epoxy groups. Polymerization of a polymer having a carbon-carbon double bond-containing group such as a vinyl group proceeds by an addition polymerization reaction using a double bond. Furthermore, the polymerization of a polymer having an aromatic heterocyclic group such as a thiophen-yl group proceeds by an addition polymerization reaction using a double bond constituting the aromatic heterocyclic ring.

  Although not particularly limited, in one embodiment, when a reaction between polymerizable functional groups having essentially the same structure is assumed, the first and second polymerizable functional groups are cyclic ethers having three or more members. A group containing a group or a group having an aromatic heterocycle is preferably contained, and a substituted or unsubstituted oxetane group or a substituted or unsubstituted thiophen-yl group is more preferred.

  As described above, in order to sufficiently insolubilize (harden) the organic layer by the polymerization reaction of the polymer with the polymerizable functional groups having essentially the same structure, it is preferable to heat to a temperature of, for example, 230 ° C. during the curing. More preferably, a polymerization initiator is used during the reaction. In particular, when each of the first polymerizable functional group and the second polymerizable functional group is a cyclic ether group having three or more members, a polymerization initiator is used and heated to a temperature of 230 ° C., for example. It is preferable to do.

  On the other hand, in the charge transporting polymer, when a group having a carbon-carbon multiple bond and an aromatic heterocyclic group coexist (more specifically, for example, the charge transporting polymer has a conjugated diene-containing group described later, In the case of having a combination with a dienophile-containing group), a mechanism different from the polymerization of a polymer having a cyclic ether group or the like described above may be taken. Specifically, the conjugated diene-containing group and the dienophile-containing group can be a substrate for a cycloaddition reaction such as Diels-Alder reaction. Therefore, in two or more kinds of charge transporting polymers, when the diene-containing group and the dienophile-containing group coexist, a cycloaddition reaction is possible, and compared with the above-described polymerization reaction between the same polymerizable functional groups, There is a tendency that the organic layer of the polymer can be easily insolubilized (cured) at a low temperature. Therefore, in one embodiment, it is preferable that the first polymerizable functional group is a conjugated diene-containing group and the second polymerizable functional group is a dienophile-containing group. Hereinafter, the conjugated diene-containing group and the dienophile-containing group will be described.

(Conjugated diene-containing group)
The conjugated diene-containing group in the charge transporting polymer generally means a group having a structure derived from a conjugated diene compound that can be used in the Diels-Alder reaction. The conjugated diene compound is not particularly limited as long as it is a compound containing two conjugated double bonds capable of reacting with the dienophile compound. The conjugated diene compound may be linear or cyclic.
In addition, the conjugated diene compound may be a compound in which a substituent such as an alkyl group is introduced into the conjugated diene skeleton. The alkyl group may have 1 to 6 carbon atoms, and may have any of a linear, branched, and cyclic structure. The conjugated diene compound preferably has a high electron density in the conjugated diene portion.

  Conjugated diene-containing groups include, for example, furan ring, thiophene ring, pyrrole ring, cyclopentadiene ring, 1,3-butadiene, thiophene-1-oxide ring, thiophene-1,1-dioxide ring, cyclopenta-2,4- A dienone ring, a 2H pyran ring, a cyclohexa-1,3-diene ring, a 2H pyran 1-oxide ring, a 1,2-dihydropyridine ring, a 2H thiopyran-1,1-dioxide ring, a cyclohexa-2,4-dienone ring, It may have a structure derived from a pyran-2-one ring and anthracene, and these structures may further have a substituent.

  From the viewpoint of reactivity, the conjugated diene-containing group is preferably a monovalent group. For example, a group obtained by removing one hydrogen atom from one structure selected from a furan ring, a thiophene ring, a cyclopentadiene ring, 1,3-butadiene, a thiophene-1,1-dioxide ring, and an anthracene. Good. The conjugated diene-containing group is a hydrogen atom from at least one selected from the group consisting of a furan ring, a cyclopentadiene ring, 1,3-butadiene, a thiophene-1,1-dioxide ring, and an anthracene from the viewpoint of reactivity. More preferably, it is a group in which one is removed. The conjugated diene-containing group is more preferably a group obtained by removing one hydrogen atom from the furan ring structure. Hereinafter, typically, a monovalent furan ring-containing group will be described more specifically.

式中、Ｒ^１〜Ｒ^３は、それぞれ独立して、水素原子、炭素数１〜６のアルキル基、−Ｃ（＝Ｏ）Ｈ、−ＣＨ_２ＯＨ、−Ｂｒ、及び−Ｃｌからなる群から選択される基を表す。「＊」は他の構造部位との結合部位を表す。 In one embodiment, the monovalent conjugated diene-containing group is preferably a monovalent furan ring-containing group represented by the following formula (I).

In the formula, R ^{1 to} R ³ are each independently a group consisting of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, —C (═O) H, —CH ₂ OH, —Br, and —Cl. Represents a selected group. “*” Represents a binding site with another structural site.

In one embodiment, the monovalent furan ring-containing group has a structure in which R ^{1 to} R ³ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms in the above formula (I). Is preferred. In other embodiments, the monovalent conjugated diene-containing group is selected from the group of formula (I) wherein R ¹ is —C (═O) H, —CH ₂ OH, —Br, and —Cl. It is preferable that R ² and R ³ each independently have a structure of a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

The monovalent furan ring-containing group preferably has a structure represented by the following formula (I-1).

In the formula, R ^{1 to} R ³ and “*” are the same as described above. In one embodiment, the monovalent furan ring-containing group has the above formula (I-1), wherein R ¹ is a hydrogen atom or —C (═O) H, and R ² and R ³ are each hydrogen. More preferably, it has a structure that is an atom. In the above ^embodiment, R 1 to R ³ is further preferably each hydrogen atom.

The monovalent furan ring-containing group may have a structure in which two furan rings are bonded, as represented by the following formula (I-2). In the formula, R ^{1 to} R ⁵ are each independently a group consisting of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, —C (═O) H, —CH ₂ OH, —Br, and —Cl. Represents a selected group. “*” Represents a binding site with another structural site. X represents a divalent linking group selected from the group consisting of linear, branched, and cyclic alkylene having 1 to 6 carbon atoms.

As one embodiment, in the above formula (I-2), R ¹ is a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and —C (═O) H; ^More preferably, ^{2 to} R ⁵ are each a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and X is a linear alkylene group having 1 to 3 carbon atoms. In the above embodiment, R ^{1 to} R ⁵ are each preferably a hydrogen atom, and more preferably X is a methylene group.

(Dienophile-containing group)
The dienophile-containing group in the charge transporting polymer generally means a group having a structure derived from a dienophile compound that can be used in the Diels-Alder reaction. The dienophile compound should just be a compound containing the double bond or triple bond which can react with a conjugated diene compound, and is not specifically limited. The dienophile compound may be a chain or a ring.

The dienophile compound preferably has a double bond, and may have a substituent introduced such as an alkyl group. The alkyl group (—C _n H _{2n + 1} ) may have 1 to 6 carbon atoms, and may have any of a linear, branched, and cyclic structure. The dienophile compound preferably has a low electron density in the double bond portion.

Dienophile-containing groups include, for example, styrene, maleic anhydride, maleic acid, maleic monoesters, maleic diesters, maleimides, fumaric acid, itaconic acid, acrolein, acrylic acid, methacrylic acid, acryloyl chloride, methacryloyl chloride, A group having a structure derived from acrylic acid esters, methacrylic acid esters, 1,4-benzoquinone, 1,4-naphthoquinone, 2,5-dihydrofurans, pyrrolines and the like is preferable. These may have a substituent in a double bond part or a part adjacent to the double bond. In one embodiment, the dienophile-containing group is preferably a monovalent group from the viewpoint of reactivity. That is, the monovalent dienophile-containing group may be, for example, a group obtained by removing one hydrogen atom from the structure of the dienophile compound exemplified above. For example, the monovalent dienophile-containing group is preferably a group obtained by removing one hydrogen atom from styrene. Hereinafter, typically, a monovalent styrene group will be described more specifically.
In one embodiment, the monovalent dienophile-containing group is preferably a monovalent styrene group represented by the following formula (II).

  In the formula, each R represents a substituent, and may be, for example, an alkyl group having 1 to 6 carbon atoms. The alkyl group may have any of a linear, branched, and cyclic structure. Adjacent Rs may be connected to each other to form a ring. n is an integer of 0-4. When n is 0, it means that the styrene structure is unsubstituted. “*” Represents a binding site with another structural site.

From the viewpoint of reactivity, the monovalent dienophile-containing group is more preferably an unsubstituted monovalent styrene group represented by the following formula (II-1). In the formula, * represents a binding site with another structural site.

In the above embodiment, the position of the vinyl group in the styrene structure may be any of the ortho position, the meta position, and the para position with respect to the binding site with other structural sites, but is represented by the following formula: Thus, the meta position or the para position is more preferable.

In one embodiment, the charge transporting polymer may have a “polymerizable functional group” as a “group containing a polymerizable functional group”. For example, although not particularly limited, from the viewpoint of increasing the degree of freedom of the polymerizable functional group and facilitating the polymerization reaction, the group containing the polymerizable functional group is a polymerizable functional group, for example, having 1 to 1 carbon atoms. It may be a group having 8 linear alkylene chains. In the group containing the polymerizable functional group, the polymerizable functional group is preferably connected to the main skeleton of the charge transporting polymer by, for example, a linear alkylene chain having 1 to 8 carbon atoms.
For example, when an organic layer is formed on an electrode, from the viewpoint of improving the affinity with a hydrophilic electrode such as ITO, the group containing a polymerizable functional group includes a polymerizable functional group and, for example, a hydrophilic chain. It may be a group having In the group containing the polymerizable functional group, the polymerizable functional group is preferably linked to the main skeleton of the charge transporting polymer by a hydrophilic chain such as an ethylene glycol chain or a diethylene glycol chain.
Furthermore, from the viewpoint of facilitating preparation of the monomer used for introducing the polymerizable functional group, the group containing the polymerizable functional group has a polymerizable functional group and an alkylene chain and / or a hydrophilic chain. Furthermore, it may be a group having an ether bond or an ester bond at the end of the alkylene chain and / or the hydrophilic chain. More specifically, the group containing the polymerizable functional group is an end portion of the alkylene chain and / or hydrophilic chain, that is, a connecting portion between these chains and the polymerizable functional group, and / or The chain may have a structure having an ether bond or an ester bond at the connecting part between the chain and the skeleton of the charge transporting polymer.

  It is preferable that a large amount of the polymerizable functional group is contained in the charge transporting polymer from the viewpoint of contributing to the change in solubility. On the other hand, from the viewpoint of not hindering the charge transporting property, it is preferable that the amount contained in the charge transporting polymer is small. The content of the polymerizable functional group can be appropriately set in consideration of these.

  For example, the number of polymerizable functional groups per molecule of the charge transporting polymer is preferably 2 or more, more preferably 3 or more from the viewpoint of obtaining a sufficient solubility change. The number of polymerizable functional groups is preferably 1,000 or less, more preferably 500 or less, from the viewpoint of maintaining charge transportability.

The number of polymerizable functional groups per molecule of the charge transporting polymer is the amount of the polymerizable functional group used to synthesize the charge transporting polymer (for example, the amount of the monomer having a polymerizable functional group), each structure The average value can be obtained by using the monomer charge corresponding to the unit and the weight average molecular weight of the charge transporting polymer. The number of polymerizable functional groups is the ratio between the integral value of the signal derived from the polymerizable functional group and the integral value of the entire spectrum in the ¹ H NMR (nuclear magnetic resonance) spectrum of the charge transporting polymer, the charge transporting polymer The weight average molecular weight can be used to calculate the average value. Since it is simple, when the preparation amount is clear, a value obtained by using the preparation amount is preferably adopted.

  In one embodiment, the proportion of the polymerizable functional group in the charge transporting polymer is preferably 0.1 mol% or more based on the total structural unit from the viewpoint of efficiently curing the charge transporting polymer. Mole% or more is more preferable, and 3 mol% or more is still more preferable. The proportion of the polymerizable functional group is preferably 70 mol% or less, more preferably 60 mol% or less, and still more preferably 50 mol% or less from the viewpoint of obtaining good charge transportability. The “ratio of polymerizable functional groups” here refers to the ratio of structural units having a polymerizable functional group.

  In one embodiment, the compounding ratio of the first charge transporting polymer having the first polymerizable functional group and the second charge transporting polymer having the second polymerizable functional group is not particularly limited, and each polymer The number of moles of the polymerizable functional group in can be adjusted in consideration. In one embodiment, the first charge transport polymer / second charge transport polymer ratio (weight ratio) may range from 20/80 to 80/20. When the number of moles of the polymerizable functional group in the polymer is substantially equal, the weight ratio of the polymer is preferably in the range of 25/75 to 75/25, more preferably in the range of 40/60 to 60/40. 50/50 is more preferable.

  In one embodiment, when the first polymerizable functional group is a conjugated diene-containing group and the second polymerizable functional group is a dienophile-containing group, for example, the first charge having a monovalent conjugated diene-containing group. The mixing ratio of the transporting polymer and the second charge transporting polymer having a monovalent dienophile-containing group is not particularly limited, and should be adjusted in consideration of the molar ratio of the conjugated diene-containing group and the dienophile-containing group. Is preferred. In one embodiment, the ratio (molar ratio) of the conjugated diene-containing group / dienophile-containing group is preferably in the range of 0.05 to 20, and preferably in the range of 0.1 to 10 from the viewpoint of efficiently proceeding with the Diels-Alder reaction. More preferably, the range of 0.25-4 is still more preferable.

  As described above, in at least two kinds of charge transporting polymers to be used in combination, the conductivity can be easily controlled by the interaction between the polymerizable functional groups of each charge transporting polymer. In one embodiment, it is preferable that the polymerizable functional groups of each charge transporting polymer have essentially the same structure from the viewpoint of the reactivity between the polymerizable functional groups. In other embodiments, each polymerizable functional group may have a different structure. In particular, it is desirable to have complementary structures such as a conjugated diene and dienophile relationship.

(Structure of charge transporting polymer)
Hereinafter, the charge transporting polymer constituting the charge transporting material will be described more specifically. In addition, the term “charge transporting polymer” described in the following description means a first charge transporting polymer having at least one first polymerizable functional group, and at least one second polymerizable functional group. Each of the second charge transporting polymers having However, since the first and second charge transporting polymers have different charge transporting capabilities, it is assumed that they have different main skeletons. The term “polymerizable functional group” means each of the first polymerizable functional group and the second polymerizable functional group described above.

  The charge transporting polymer may be linear or branched. In one embodiment, the charge transporting polymer preferably includes a trivalent or higher valent structural unit B constituting a branched portion and has a structure branched in three or more directions. Here, the term “trivalent or higher” in the structural unit means that there are three or more bonds in the structural unit that form a binding site with another structural unit. That is, the valence of the structural unit corresponds to the number of bonds.

  In one embodiment, the charge transporting polymer includes a trivalent or higher structural unit B constituting a branched portion, and further includes a monovalent structural unit T forming at least a terminal portion. In another embodiment, the charge transporting polymer includes the trivalent or higher structural unit B, and further includes the bivalent structural unit L having charge transporting property and the monovalent structural unit T. The charge transporting polymer may contain only one kind of each structural unit, or may contain plural kinds of structural units. In the charge transporting polymer, each structural unit is bonded to each other at a binding site of “monovalent” to “trivalent or higher”.

  Examples of the partial structure contained in the charge transporting polymer having a structure branched in three or more directions include the following. The charge transporting polymer is not limited to those having the following partial structures. In the partial structure, “B” represents the structural unit B, “L” represents the structural unit L, and “T” represents the structural unit T. “*” Represents a binding site with another structural unit. In the following partial structures, the plurality of Bs may be the same structural unit or different structural units. The same applies to T and L.

Examples of charge transporting polymers having a branched structure

In the charge transporting polymer, the polymerizable functional group is introduced into a portion other than the terminal portion (that is, the structural unit L or B) even if it is introduced into the terminal portion (that is, the structural unit T) of the charge transporting polymer. Even if it is, it may be introduced into both a terminal part and parts other than a terminal. From the viewpoint of curability, it is preferably introduced at least at the end portion, and from the viewpoint of achieving both curability and charge transportability, it is preferably introduced only at the end portion. The polymerizable functional group may be introduced into the main chain of the charge transporting polymer, may be introduced into the side chain, or may be introduced into both the main chain and the side chain.
In one embodiment, from the viewpoint of facilitating the reactivity between the charge transporting polymers, it is preferable that at least one of the first and second charge transporting polymers has at least one polymerizable functional group at a terminal, More preferably, each of the polymers has at least one polymerizable functional group at the terminal. Hereinafter, each structural unit will be specifically described.

(Structural unit L)
The structural unit L is a divalent structural unit having charge transportability. The structural unit L is not particularly limited as long as it contains an atomic group having the ability to transport charges. For example, the structural unit L is a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, fluorene structure, benzene structure, biphenyl structure, terphenyl structure, naphthalene structure, anthracene structure, tetracene structure, phenanthrene structure, dihydro Phenanthrene structure, pyridine structure, pyrazine structure, quinoline structure, isoquinoline structure, quinoxaline structure, acridine structure, diazaphenanthrene structure, furan structure, pyrrole structure, oxazole structure, oxadiazole structure, thiazole structure, thiadiazole structure, triazole structure, benzo Thiophene structure, benzoxazole structure, benzooxadiazole structure, benzothiazole structure, benzothiadiazole structure, benzotriazole structure, and one or two of these It is selected from the structure including the upper. Among the aromatic amine structures, a triarylamine structure is preferable, and a triphenylamine structure is more preferable. Of the benzene structures, a p-phenylene structure and an m-phenylene structure are preferable.

In one embodiment, the structural unit L is a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, bithiophene structure, fluorene structure, benzene structure, pyrrole structure, from the viewpoint of obtaining excellent hole transport properties. And a structure containing one or more of these, preferably selected from a substituted or unsubstituted aromatic amine structure, carbazole structure, and a structure containing one or more of these. More preferably.
In another embodiment, from the viewpoint of obtaining excellent electron transport properties, the structural unit L is a substituted or unsubstituted fluorene structure, benzene structure, phenanthrene structure, pyridine structure, quinoline structure, and one or two of these. It is preferably selected from structures containing more than one species.

Specific examples of the structural unit L include the following. The structural unit L is not limited to the following.

Each R independently represents a hydrogen atom or a substituent. Preferably, each R independently represents —R ¹ , —OR ² , —SR ³ , —OCOR ⁴ , —COOR ⁵ , —SiR ⁶ R ⁷ R ⁸ , a halogen atom, and the above-mentioned “polymerizable functional group”. Selected from the group consisting of: R ^{1 to} R ⁸ each independently represents a hydrogen atom; a linear, cyclic or branched alkyl group having 1 to 22 carbon atoms; or an aryl group or heteroaryl group having 2 to 30 carbon atoms. The aryl group is an atomic group obtained by removing one hydrogen atom from an aromatic hydrocarbon. A heteroaryl group is an atomic group obtained by removing one hydrogen atom from an aromatic heterocyclic ring. The alkyl group may be further substituted by an aryl group or heteroaryl group having 2 to 20 carbon atoms, and the aryl group or heteroaryl group is further linear, cyclic or branched having 1 to 22 carbon atoms. It may be substituted with an alkyl group. R is preferably a hydrogen atom, an alkyl group, an aryl group, or an alkyl-substituted aryl group.
Ar represents an arylene group or heteroarylene group having 2 to 30 carbon atoms. An arylene group is an atomic group obtained by removing two hydrogen atoms from an aromatic hydrocarbon. A heteroarylene group is an atomic group obtained by removing two hydrogen atoms from an aromatic heterocycle. Ar is preferably an arylene group, more preferably a phenylene group.

(Structural unit T)
The structural unit T is a monovalent structural unit constituting the terminal portion of the charge transporting polymer. The structural unit T is not particularly limited. For example, the structural unit T preferably has a substituted or unsubstituted aromatic hydrocarbon structure, aromatic heterocyclic structure, and a structure including one or more of these. In one embodiment, the structural unit T preferably has a substituted or unsubstituted aromatic hydrocarbon structure from the viewpoint of imparting durability without deteriorating charge transportability, and substituted or unsubstituted benzene. More preferably, it has a structure.

In one embodiment, the charge transporting polymer preferably has a polymerizable functional group at each terminal portion. Therefore, in one embodiment, the structural unit T has an aromatic hydrocarbon structure, an aromatic heterocyclic structure, and a structure including one or more of these, and a polymerizable functional group as a substituent. What has is preferable. The polymerizable functional group is as described above. For example, in one embodiment, the polymerizable functional group in the structural unit T is independently composed of an epoxy group, an oxetane group, a vinyl group, an acrylate group, a methacrylate group, a furan-yl group, and a thiophen-yl group. It is preferably at least one selected from the group. Among them, a group having an aromatic heterocyclic structure such as a furan-yl group and a thiophen-yl group can itself be a structural unit T constituting the terminal portion of the polymer.
The following is mentioned as an example of the structural unit T which comprises the charge transportable polymer which has a polymerizable functional group in the terminal part.

_{-Ar- (CH 2) a -X (} t1)
_{-Ar-O- (CH 2) a} -X (t2)
In the formula, Ar represents an arylene group or heteroarylene group having 2 to 30 carbon atoms, a is an integer of 0 to 8, and X represents a substituted or unsubstituted polymerizable functional group. As specific examples of the group containing the polymerizable functional group described above, the “— (CH ₂ ) _a —X” and “—O— (CH ₂ ) _a —X” in the above formulas (t1) and (t2) Structure is mentioned. The polymerizable functional group is as described above, and is preferably a substituted or unsubstituted oxetane group, an epoxy group, or a vinyl group, for example.
In another embodiment of the structural unit T constituting the charge transporting polymer having a polymerizable functional group at the terminal portion, the structural unit T is preferably a furan-yl group or a thiophen-yl group, and each ring May have a substituent.

  In one embodiment, the charge transporting material preferably includes polymerizable functional groups having the same structure in two or more kinds of polymerizable charge transporting polymers. For example, the polymerizable functional group is preferably an oxetane group or a thiophene-yl group. As a specific example of the above-described embodiment, the first and second charge transporting polymers preferably have any one of the structures described below as the structural unit T.

式中、＊は他の構造単位との結合部位を表し、Ｒ１〜Ｒ３は、それぞれ独立して、水素原子又は置換基を表す。置換基は、例えば、炭素数１〜８のアルキル基であることが好ましい。
他の実施形態において電荷輸送性材料は、２種以上の重合可能な電荷輸送性ポリマーにおいて、互いに異なる構造を有する重合性官能基を含むことが好ましい。なかでも、重合性官能基が互いに相補的な関係になることがより好ましい。例えば、重合性官能基の一方はフラン−１イル基であり、他方はビニル基（スチレン基）であることが好ましい。上記実施形態の具体例として、第１及び第２の電荷輸送性ポリマーは、構造単位として、それぞれ以下に記載する構造の組合せを有することが好ましい。

In formula, * represents the coupling | bond part with another structural unit, R1-R3 represents a hydrogen atom or a substituent each independently. The substituent is preferably, for example, an alkyl group having 1 to 8 carbon atoms.
In another embodiment, the charge transporting material preferably includes polymerizable functional groups having structures different from each other in two or more kinds of polymerizable charge transporting polymers. Among these, it is more preferable that the polymerizable functional groups are complementary to each other. For example, it is preferable that one of the polymerizable functional groups is a furan-1yl group and the other is a vinyl group (styrene group). As a specific example of the above embodiment, the first and second charge transporting polymers preferably have a combination of structures described below as structural units.

式中、＊は他の構造単位との結合部位を表し、Ｒ４及びＲ５は、それぞれ独立して、水素原子又は置換基を表す。置換基は、例えば、炭素数１〜８のアルキル基であることが好ましい。一実施形態において、Ｒ４及びＲ５は、それぞれ独立して、水素原子であることが好ましい。

In the formula, * represents a bonding site with another structural unit, and R4 and R5 each independently represent a hydrogen atom or a substituent. The substituent is preferably, for example, an alkyl group having 1 to 8 carbon atoms. In one embodiment, R 4 and R 5 are preferably each independently a hydrogen atom.

In addition, the charge transporting polymer may have the following structure as the structural unit T.

  R may be the same as R in the structural unit L, but does not contain a polymerizable functional group.

(Structural unit B)
The structural unit B is a trivalent or higher structural unit that constitutes a branched portion when the charge transporting polymer or oligomer has a branched structure. The structural unit B is preferably hexavalent or less, more preferably trivalent or tetravalent, from the viewpoint of improving the durability of the organic electronic element. The structural unit B is preferably a unit having charge transportability. For example, the structural unit B is a substituted or unsubstituted aromatic amine structure, carbazole structure, condensed polycyclic aromatic hydrocarbon structure, and one or two of these from the viewpoint of improving the durability of the organic electronic device. Selected from structures containing more than one species. The structural unit B may have the same structure as the structural unit L or may have a different structure, may have the same structure as the structural unit T, or may have a different structure. You may have.

Specific examples of the structural unit B include the following. The structural unit B is not limited to the following.

W represents a trivalent linking group, for example, an arenetriyl group or a heteroarenetriyl group having 2 to 30 carbon atoms. As described above, the arenetriyl group is an atomic group obtained by removing three hydrogen atoms from an aromatic hydrocarbon. The heteroarene triyl group is an atomic group obtained by removing three hydrogen atoms from an aromatic heterocyclic ring. Ar each independently represents a divalent linking group, for example, each independently represents an arylene group or heteroarylene group having 2 to 30 carbon atoms.
Ar is preferably an arylene group, more preferably a phenylene group. Y represents a divalent linking group, for example, a group having one or more hydrogen atoms out of R in the structural unit L (excluding the above-mentioned “group containing a polymerizable functional group”); And a divalent group in which one hydrogen atom is removed. Z represents any of a carbon atom, a silicon atom, or a phosphorus atom. In the structural unit, the benzene ring and Ar may have a substituent, and examples of the substituent include R in the structural unit L.

Among the charge transporting polymers described above, a combination of a first charge transporting polymer having a first polymerizable functional group and a second charge transporting polymer having a second polymerizable functional group is preferable. The following is mentioned as an example.
(1) At least one of the first charge transporting polymer and the second charge transporting polymer is selected from the group consisting of a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, benzene structure, and fluorene structure. It preferably contains at least one selected structure.
(2) At least one of the first charge transporting polymer and the second charge transporting polymer is a divalent structural unit or a trivalent or higher structural unit, a substituted or unsubstituted aromatic amine structure and carbazole structure It is more preferable to include at least one of the structures.
(3) At least one of the first charge transporting polymer and the second charge transporting polymer includes at least one of a substituted or unsubstituted aromatic amine structure and carbazole structure as a trivalent structural unit. More preferably.
In one embodiment, the first and second charge transporting polymers have the terminal structure T1 exemplified above by the first and second polymerizable functional groups in addition to the structures (1) to (3). And a structure capable of polymerizing with a ring-opening reaction such as T2 or a structure in which a bond is formed between polymerizable functional groups such as terminal structure T3.
In another embodiment, the first and second charge transporting polymers have the terminal structures exemplified above by the first and second polymerizable functional groups in addition to the structures of (1) to (3) above. It is preferable to have a structure in which a bond is formed between two or more different structures, such as a combination of T4 and T5. Although there is no particular limitation, when the combination of the first and second charge transporting polymers has a combination of a substituted or unsubstituted aromatic amine structure and a carbazole structure, the charge transporting layer is excellent. It tends to be easy to obtain conductivity.

(Number average molecular weight)
The number average molecular weight of the charge transporting polymer can be appropriately adjusted in consideration of solubility in a solvent, film formability, and the like. From the viewpoint of excellent charge transportability, the number average molecular weight is preferably 500 or more, more preferably 1,000 or more, and still more preferably 2,000 or more. The number average molecular weight is preferably 18,000 or more. 20,000 or more is more preferable, and 30,000 or more is more preferable. The number average molecular weight is preferably 1,000,000 or less, more preferably 500,000 or less, and more preferably 200,000 from the viewpoint of maintaining good solubility in a solvent and facilitating preparation of an ink composition. The following is more preferable.

(Weight average molecular weight)
The weight average molecular weight of the charge transporting polymer can be appropriately adjusted in consideration of solubility in a solvent, film formability, and the like. The weight average molecular weight is preferably 1,000 or more, more preferably 5,000 or more, and still more preferably 10,000 or more, from the viewpoint of excellent charge transportability. Further, the weight average molecular weight is preferably 1,000,000 or less, more preferably 700,000 or less, and more preferably 400,000 from the viewpoint of maintaining good solubility in a solvent and facilitating preparation of an ink composition. The following is more preferable, and 300,000 or less is most preferable. In one embodiment, the weight average molecular weight of the charge transporting polymer is particularly preferably 200,000 or less.

  The number average molecular weight and the weight average molecular weight can be measured by gel permeation chromatography (GPC) using a standard polystyrene calibration curve.

(Percentage of structural units)
The proportion of the structural unit L contained in the charge transporting polymer is preferably 10 mol% or more, more preferably 20 mol% or more, and more preferably 30 mol% or more based on the total structural unit from the viewpoint of obtaining sufficient charge transportability. Is more preferable. Further, the ratio of the structural unit L is preferably 95 mol% or less, more preferably 90 mol% or less, and still more preferably 85 mol% or less in consideration of the structural unit T and the structural unit B introduced as necessary.

  The proportion of the structural unit T contained in the charge transporting polymer is based on the total structural unit from the viewpoint of improving the characteristics of the organic electronics element or suppressing the increase in the viscosity and satisfactorily synthesizing the charge transporting polymer. 5 mol% or more is preferable, 10 mol% or more is more preferable, and 15 mol% or more is still more preferable. The proportion of the structural unit T is preferably 60 mol% or less, more preferably 55 mol% or less, and still more preferably 50 mol% or less from the viewpoint of obtaining sufficient charge transport properties.

  When the charge transporting polymer contains the structural unit B, the proportion of the structural unit B is preferably 1 mol% or more, more preferably 5 mol% or more, based on the total structural units, from the viewpoint of improving the durability of the organic electronics element. 10 mol% or more is more preferable. The proportion of the structural unit B is preferably 50 mol% or less, preferably 40 mol% or less, from the viewpoint of suppressing the increase in viscosity and satisfactorily synthesizing the charge transporting polymer or obtaining sufficient charge transportability. Is more preferable, and 30 mol% or less is still more preferable.

  Considering the balance of charge transportability, durability, productivity, etc., the ratio (molar ratio) of the structural unit L and the structural unit T is preferably L: T = 100: 1 to 70, more preferably 100: 3 to 50. Preferably, 100: 5-30 is more preferable. When the charge transporting polymer includes the structural unit B, the ratio (molar ratio) of the structural unit L, the structural unit T, and the structural unit B is L: T: B = 100: 10 to 200: 10 to 100. Preferably, 100: 20-180: 20-90 are more preferable, and 100: 40-160: 30-80 are still more preferable.

The proportion of the structural unit can be determined by using the charged amount of the monomer corresponding to each structural unit used for synthesizing the charge transporting polymer. Moreover, the ratio of the structural unit can be calculated as an average value using an integrated value of the spectrum derived from each structural unit in the ¹ H NMR spectrum of the charge transporting polymer. Since it is simple, when the preparation amount is clear, a value obtained by using the preparation amount is preferably adopted.

  In a particularly preferred embodiment, the charge transporting polymer is mainly composed of a structural unit having an aromatic amine structure and / or a structural unit having a carbazole structure from the viewpoint of having a high hole injection property, a hole transporting property, and the like. A compound having a unit (main skeleton) is preferred. The charge transporting polymer is preferably a compound having at least two polymerizable substituents from the viewpoint of easily multilayering. From the viewpoint of having excellent curability, the polymerizable substituent is preferably a group having a cyclic ether structure, a group having a carbon-carbon multiple bond, or the like.

(Production method)
The charge transporting polymer can be produced by various synthetic methods and is not particularly limited. For example, known coupling reactions such as Suzuki coupling, Negishi coupling, Sonogashira coupling, Stille coupling, Buchwald-Hartwig coupling and the like can be used. Suzuki coupling causes a cross coupling reaction using a Pd catalyst between an aromatic boronic acid derivative and an aromatic halide. According to Suzuki coupling, a charge transporting polymer can be easily produced by bonding desired aromatic rings together.

  In the coupling reaction, for example, a Pd (0) compound, a Pd (II) compound, a Ni compound, or the like is used as a catalyst. In addition, a catalyst species generated by mixing tris (dibenzylideneacetone) dipalladium (0), palladium (II) acetate and the like with a phosphine ligand can also be used. For the method for synthesizing the charge transporting polymer, for example, the description in WO 2010/140553 can be referred to.

[Dopant]
The charge transport material may contain any additive, and may further contain, for example, a dopant. The dopant can be added to the charge transport material to develop a doping effect and improve the charge transport property. There is no particular limitation as long as it can be obtained. Doping includes p-type doping and n-type doping. In p-type doping, a substance serving as an electron acceptor is used as a dopant, and in n-type doping, a substance serving as an electron donor is used as a dopant. It is preferable to perform p-type doping for improving hole transportability and n-type doping for improving electron transportability. The dopant used for the charge transporting material may be a dopant that exhibits any effect of p-type doping or n-type doping. Further, one kind of dopant may be added alone, or plural kinds of dopants may be mixed and added.

The dopant used for p-type doping is an electron-accepting compound, and examples thereof include Lewis acids, proton acids, transition metal compounds, ionic compounds, halogen compounds, and π-conjugated compounds. Specifically, as the Lewis acid, FeCl ₃ , PF ₅ , AsF ₅ , SbF ₅ , BF ₅ , BCl ₃ , BBr _{3 and the} like; as the protonic acid, HF, HCl, HBr, HNO ₅ , H ₂ SO ₄ , HClO _{4 and} other inorganic acids, benzenesulfonic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, polyvinylsulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid, 1-butanesulfonic acid, vinylphenylsulfonic acid Organic acids such as camphorsulfonic acid; transition metal compounds include FeOCl, TiCl ₄ , ZrCl ₄ , HfCl ₄ , NbF ₅ , AlCl ₃ , NbCl ₅ , TaCl ₅ , MoF ₅ ; Phenyl) borate ion, tris (trifluoro) Methanesulfonyl) Mechidoion, bis (trifluoromethanesulfonyl) imide ion, hexafluoroantimonate ion, AsF ₆ ^- (hexafluoro arsenic acid ions), BF ₄ ^- (tetrafluoroborate), PF ₆ ^- (hexafluorophosphate) A salt having a perfluoroanion such as a salt, a salt having a conjugate base of the protonic acid as an anion; halogen compounds such as Cl ₂ , Br ₂ , I ₂ , ICl, ICl ₃ , IBr and IF; π-conjugated compounds Examples thereof include TCNE (tetracyanoethylene), TCNQ (tetracyanoquinodimethane) and the like. Moreover, it is also possible to use the electron-accepting compounds described in JP 2000-36390 A, JP 2005-75948 A, JP 2003-213002 A, and the like. Preferred are Lewis acids, ionic compounds, π-conjugated compounds and the like.

The dopant used for the n-type doping is an electron-donating compound, for example, an alkali metal such as Li or Cs, an alkaline earth metal such as Mg or Ca, an alkali metal such as LiF or Cs ₂ CO ₃ , and / or Alternatively, alkaline earth metal salts, metal complexes, electron-donating organic compounds, and the like can be given.

  In the above dopant, the ionic compound also functions as a polymerization initiator. The charge transporting material containing the charge transporting polymer disclosed in the present specification can be insolubilized without using a polymerization initiator. However, if necessary, the charge transporting material is intended to improve the charge transporting property. An ionic compound may be included.

[Other optional ingredients]
The charge transporting material may further contain a charge transporting low molecular weight compound, other polymers, and the like.

[Content]
The content of the charge transporting polymer in the charge transporting material is preferably 50% by mass or more and 70% by mass or more with respect to the total mass of the charge transporting material from the viewpoint of obtaining good charge transporting properties. More preferably, 80 mass% or more is still more preferable. The upper limit of the content of the charge transporting polymer is not particularly limited, and may be 100% by mass. In consideration of including an additive such as a dopant, the content of the charge transporting polymer may be, for example, 95% by mass or less, 90% by mass or less, and the like.

  When the dopant is contained, the content thereof is preferably 0.01% by mass or more, and 0.1% by mass with respect to the total mass of the charge transporting material, from the viewpoint of improving the charge transporting property of the charge transporting material. The above is more preferable, and 0.5% by mass or more is still more preferable. Further, from the viewpoint of maintaining good film formability, the content is preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 20% by mass or less with respect to the total mass of the charge transporting material.

<Ink composition>
In one embodiment, in order to form a charge transport layer, an ink composition containing the charge transport material of the above embodiment and a solvent capable of dissolving or dispersing the material may be used. By using the ink composition, the charge transport layer (organic layer) can be easily formed by a simple method such as a coating method.

[solvent]
As the solvent, water, an organic solvent, or a mixed solvent thereof can be used. Organic solvents include alcohols such as methanol, ethanol and isopropyl alcohol; alkanes such as pentane, hexane and octane; cyclic alkanes such as cyclohexane; aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, tetralin and diphenylmethane; ethylene glycol Aliphatic ethers such as dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate; 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, Aromatic ethers such as 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole; ethyl acetate, n-butyl acetate, ethyl lactate, n-butyl lactate Aliphatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, n-butyl benzoate; N, N-dimethylformamide, N, N-dimethylacetamide, etc. Amide solvents; dimethyl sulfoxide, tetrahydrofuran, acetone, chloroform, methylene chloride and the like can be mentioned. Preferred are aromatic hydrocarbons, aliphatic esters, aromatic esters, aliphatic ethers, aromatic ethers and the like.

[Additive]
The ink composition may further contain an additive as an optional component. Examples of additives include polymerization inhibitors, stabilizers, thickeners, gelling agents, flame retardants, antioxidants, antioxidants, oxidizing agents, reducing agents, surface modifiers, emulsifiers, antifoaming agents, Examples thereof include a dispersant and a surfactant.

[Content]
The content of the solvent in the ink composition can be determined in consideration of application to various coating methods. For example, the content of the solvent is preferably such that the ratio of the charge transporting polymer to the solvent is 0.1% by mass or more, more preferably 0.2% by mass or more, and 0.5% by mass or more. More preferred is an amount of The content of the solvent is preferably such that the ratio of the charge transporting polymer to the solvent is 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less. .

<Charge transport layer (organic layer)>
In one embodiment, the charge transport layer is an organic layer formed using the charge transport material or ink composition of the above embodiment (hereinafter, the charge transport layer is also referred to as an organic layer). Therefore, in one embodiment, the method for controlling the conductivity of the charge transport layer may include a step of mixing two or more charge transport polymers that can be polymerized with each other in order to obtain a charge transport material. . In another embodiment, the ink transporting material may be mixed with a solvent to prepare an ink composition.
By using the ink composition, the organic layer can be satisfactorily and easily formed by a coating method. Examples of the coating method include spin coating method; casting method; dipping method; letterpress printing, intaglio printing, offset printing, planographic printing, letterpress inversion offset printing, screen printing, gravure printing and other plate printing methods; ink jet method, etc. A known method such as a plateless printing method may be used. When the organic layer is formed by a coating method, the organic layer (coating layer) obtained after the coating may be dried using a hot plate or an oven to remove the solvent.

  Since the charge transporting polymer has a polymerizable functional group, the solubility of the organic layer can be changed by proceeding the polymerization reaction of the charge transporting polymer by light irradiation, heat treatment or the like. By laminating organic layers with different solubility, it is possible to easily increase the number of organic electronics elements. For the method for forming the organic layer, for example, the description of WO 2010/140553 can be referred to.

  In the method for controlling the conductivity of the charge transport layer disclosed herein, a charge transport material comprising two or more polymerizable charge transport polymers, or the material and a solvent, is used to form the charge transport layer. An ink composition containing The charge transport layer can be formed according to the organic layer forming method by the coating method described above. In one embodiment, the charge transport layer (organic layer) can be formed by, for example, heating the coating layer after coating the charge transport material or ink composition of the above embodiment. The heating temperature is not particularly limited, but when the polymerizable functional group in the charge transporting polymer is a complementary combination such as a conjugated diene-containing group and a dienophile-containing group, the Diels-Alder reaction proceeds and the heating is performed at a temperature of less than 230 ° C. Even so, the charge transport layer can be sufficiently cured (insolubilized). In one embodiment, the heating temperature during curing is preferably 120 ° C. or higher, more preferably 130 ° C. or higher, and even more preferably 150 ° C. or higher. Depending on the type of polymerizable functional group, the heating temperature during curing may be 230 ° C. or higher. The heating temperature at the time of curing is preferably 350 ° C. or less, more preferably 250 ° C. or less in consideration of the influence of the heating on the organic layer and the substrate. The heating time is not particularly limited, but is preferably adjusted within 60 minutes, and more preferably within 30 minutes, from the viewpoint of suppressing deterioration in performance of the organic layer due to heating.

  From the viewpoint of improving the efficiency of charge transport, the thickness of the organic layer after drying or curing is preferably 0.1 nm or more, more preferably 1 nm or more, and further preferably 3 nm or more. In addition, the thickness of the organic layer is preferably 300 nm or less, more preferably 200 nm or less, and still more preferably 100 nm or less, from the viewpoint of reducing electrical resistance.

<Organic electronics elements>
In one embodiment, the organic electronic device has at least one charge transport layer (organic layer) of the above-described embodiment. That is, in one embodiment, the organic electronic device includes a charge transport material containing two or more polymerizable charge transport polymers, or a charge transport formed using an ink composition containing the material and a solvent. Including layers. According to the embodiment described above, the conductivity of the charge transport layer can be appropriately controlled, so that it is easy to improve the characteristics of the organic electronics element. Examples of the organic electronics element include an organic EL element, an organic photoelectric conversion element, and an organic transistor. The organic electronic element preferably has a structure in which an organic layer is disposed between at least a pair of electrodes.

<Organic EL device>
In one embodiment, the organic EL element has at least one charge transport layer (organic layer) of the above-described embodiment. That is, in one embodiment, the organic EL device is formed by using a charge transporting material containing two or more polymerizable charge transporting polymers or an ink composition containing the material and a solvent. Including layers. According to the embodiment described above, the conductivity of the charge transport layer can be appropriately controlled, so that it is easy to improve the characteristics of the organic EL element.
The organic EL element usually includes a light emitting layer, an anode, a cathode, and a substrate, and other functional layers such as a hole injection layer, an electron injection layer, a hole transport layer, and an electron transport layer are provided as necessary. I have. Each layer may be formed by a vapor deposition method or a coating method. The organic EL element preferably has the organic layer as a light emitting layer or other functional layer, more preferably as a functional layer, and still more preferably as at least one of a hole injection layer and a hole transport layer.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of an organic EL element. The organic EL element of FIG. 1 is an element having a multilayer structure, and includes a substrate 8, an anode 2, a hole injection layer 3 and a hole transport layer 6, a light emitting layer 1, an electron transport layer 7, an electron injection layer 5, and a cathode 4. In this order. Hereinafter, each layer will be described.

[Light emitting layer]
As a material used for the light emitting layer, a light emitting material such as a low molecular compound, a polymer, or a dendrimer can be used. A polymer is preferable because it has high solubility in a solvent and is suitable for a coating method. Examples of the light emitting material include a fluorescent material, a phosphorescent material, a thermally activated delayed fluorescent material (TADF), and the like.

  Low molecular weight compounds such as perylene, coumarin, rubrene, quinacdrine, stilbene, dye laser dyes, aluminum complexes, and derivatives thereof; polyfluorene, polyphenylene, polyphenylene vinylene, polyvinyl carbazole, fluorene-benzothiadiazole copolymer , Fluorene-triphenylamine copolymers, polymers thereof such as derivatives thereof; mixtures thereof and the like.

As the phosphorescent material, a metal complex containing a metal such as Ir or Pt can be used. Examples of the Ir complex include FIr (pic) that emits blue light (iridium (III) bis [(4,6-difluorophenyl) -pyridinate-N, C ² ] picolinate), Ir (ppy) ₃ that emits green light. (Factris (2-phenylpyridine) iridium), which emits red light (btp) ₂ Ir (acac) (bis [2- (2′-benzo [4,5-α] thienyl) pyridinate-N, C ³ ] Iridium (acetyl-acetonate)), Ir (piq) ₃ (tris (1-phenylisoquinoline) iridium) and the like. Examples of the Pt complex include PtOEP (2, 3, 7, 8, 12, 13, 17, 18-octaethyl-21H, 23H-porphyrin platinum) that emits red light.

  When the light emitting layer includes a phosphorescent material, it is preferable that a host material is further included in addition to the phosphorescent material. As the host material, a low molecular compound, a polymer, or a dendrimer can be used. Examples of the low molecular weight compound include CBP (4,4′-bis (9H-carbazol-9-yl) biphenyl), mCP (1,3-bis (9-carbazolyl) benzene), CDBP (4,4′- Bis (carbazol-9-yl) -2,2′-dimethylbiphenyl), derivatives thereof, and the like. Examples of the polymer include the charge transport material of the above embodiment, polyvinyl carbazole, polyphenylene, polyfluorene, derivatives thereof, and the like. Can be mentioned.

  Examples of thermally activated delayed fluorescent materials include Adv. Mater., 21, 4802-4906 (2009); Appl. Phys. Lett., 98, 083302 (2011); Chem. Comm., 48, 9580 (2012). Appl. Phys. Lett., 101, 093306 (2012); J. Am. Chem. Soc., 134, 14706 (2012); Chem. Comm., 48, 11392 (2012); Nature, 492, 234 (2012 ); Adv. Mater., 25, 3319 (2013); J. Phys. Chem. A, 117, 5607 (2013); Phys. Chem. Chem. Phys., 15, 15850 (2013); Chem. Comm., 49, 10385 (2013); Chem. Lett., 43, 319 (2014) and the like.

[Hole injection layer, hole transport layer]
The organic layer formed using the above charge transporting material is preferably used as at least one of a hole injection layer and a hole transport layer, and more preferably at least used as a hole transport layer. As described above, these layers can be easily formed by using an ink composition containing a charge transporting material.
When the organic EL element has an organic layer formed using the above charge transporting material as a hole transport layer and further has a hole injection layer, a known material can be used for the hole injection layer. In addition, when the organic EL element has an organic layer formed using the above charge transporting material as a hole injection layer and further has a hole transport layer, a known material is used for the hole transport layer. it can.

  When a material made of triphenylamine is used for the hole injection layer, it is preferable to use the charge transport material of the present embodiment for the hole transport layer from the viewpoint of energy level with respect to the movement of holes. .

[Electron transport layer, electron injection layer]
Examples of materials used for the electron transport layer and the electron injection layer include phenanthroline derivatives, bipyridine derivatives, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, condensed ring tetracarboxylic anhydrides such as naphthalene and perylene, carbodiimides, and the like. Fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, thiadiazole derivatives, benzimidazole derivatives, quinoxaline derivatives, aluminum complexes, and the like. In addition, the charge transport material of the above embodiment can also be used.

[cathode]
As the cathode material, for example, a metal or a metal alloy such as Li, Ca, Mg, Al, In, Cs, Ba, Mg / Ag, LiF, and CsF is used.

[anode]
As the anode material, for example, a metal (for example, Au) or another material having conductivity is used. Examples of other materials include oxides (for example, ITO: indium oxide / tin oxide) and conductive polymers (for example, polythiophene-polystyrene sulfonic acid mixture (PEDOT: PSS)).

[substrate]
As the substrate, glass, plastic or the like can be used. The substrate is preferably transparent and is preferably a flexible substrate having flexibility. Quartz glass, light transmissive resin film, and the like are preferably used.

  Examples of the resin film include polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, cellulose triacetate, and cellulose acetate propionate. Can be mentioned.

  When using a resin film, in order to suppress permeation | transmission of water vapor | steam, oxygen, etc., you may coat and use inorganic substances, such as a silicon oxide and a silicon nitride, on a resin film.

[Sealing]
The organic EL element may be sealed in order to reduce the influence of outside air and extend the life. As a material used for sealing, glass, epoxy resin, acrylic resin, polyethylene terephthalate, polyethylene naphthalate and other plastic films, or inorganic materials such as silicon oxide and silicon nitride can be used. Absent. The sealing method is not particularly limited, and can be performed by a known method.

[Luminescent color]
The emission color of the organic EL element is not particularly limited. The white organic EL element is preferable because it can be used for various lighting devices such as home lighting, interior lighting, a clock, or a liquid crystal backlight.

  As a method of forming a white organic EL element, a method of simultaneously emitting light of a plurality of emission colors using a plurality of light emitting materials and mixing the colors can be used. A combination of a plurality of emission colors is not particularly limited, but a combination containing three emission maximum wavelengths of blue, green and red, a combination containing two emission maximum wavelengths of blue and yellow, yellow green and orange, etc. Is mentioned. The emission color can be controlled by adjusting the type and amount of the light emitting material.

<Display element, lighting device, display device>
In one embodiment, the display element includes the organic EL element of the above embodiment. For example, a color display element can be obtained by using an organic EL element as an element corresponding to each pixel of red, green, and blue (RGB). Image forming methods include a simple matrix type in which individual organic EL elements arranged in a panel are directly driven by electrodes arranged in a matrix, and an active matrix type in which a thin film transistor is arranged and driven in each element.

  Moreover, in one Embodiment, the illuminating device is provided with the organic EL element of the said embodiment. Furthermore, in one embodiment, the display device includes a lighting device and a liquid crystal element as display means. For example, the display device can be a display device that uses the illumination device of the above-described embodiment as a backlight and uses a known liquid crystal element as a display unit, that is, a liquid crystal display device.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples. Unless otherwise specified, “%” means “% by mass”.
1. Preparation of charge transporting polymer <Preparation of Pd catalyst>
In a glove box under a nitrogen atmosphere, tris (dibenzylideneacetone) dipalladium (73.2 mg, 80 μmol) was weighed in a sample tube at room temperature, toluene (15 ml) was added, and the mixture was stirred for 30 minutes. Similarly, tris (t-butyl) phosphine (129.6 mg, 640 μmol) was weighed in a sample tube, toluene (5 ml) was added, and the mixture was stirred for 5 minutes. These solutions were mixed and stirred at room temperature for 30 minutes to obtain a catalyst. All solvents were used after being degassed with nitrogen bubbles for more than 30 minutes.

<Charge transporting polymer 1>
In a three-neck round bottom flask, the following monomer B1 (4.0 mmol), the following monomer L1 (10.0 mmol), the following monomer T1 (8.0 mmol), and toluene (100.2 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. After stirring for 30 minutes, 3M aqueous potassium hydroxide solution (13.5 mL) was added. All solvents were used after being degassed with nitrogen bubbles for more than 30 minutes. The mixture was heated to reflux for 2 hours. All the operations so far were performed under a nitrogen stream.

  After completion of the reaction, the organic layer was washed with water, and the organic layer was poured into methanol-water (9: 1). The resulting precipitate was collected by suction filtration and washed with butyl acetate to obtain a precipitate. The resulting precipitate was collected by suction filtration, dissolved in toluene, and a metal adsorbent (“Triphenylphosphine, polymer-bound on styrene-divinylbenzene copolymer” manufactured by Strem Chemicals, 200 mg for 100 mg of the precipitate) was added. Stir overnight. After completion of the stirring, the metal adsorbent and insoluble matter were removed by filtration, and the filtrate was concentrated with a rotary evaporator. The concentrate was dissolved in toluene and then reprecipitated from methanol-acetone (8: 3). The resulting precipitate was collected by suction filtration and washed with methanol-acetone (8: 3). The obtained precipitate was vacuum-dried to obtain a charge transporting polymer 1.

  The number average molecular weight of the obtained charge transporting polymer 1 was 45,800, and the weight average molecular weight was 114,900. The charge transporting polymer 1 has a structural unit B1, a structural unit L1, and a structural unit T1, and the proportion (molar ratio) of each structural unit was 18.2%, 45.5%, and 36.3%. It was.

The number average molecular weight and the mass average molecular weight were measured by GPC (polystyrene conversion) using tetrahydrofuran (THF) as an eluent. The measurement conditions are as follows.
Liquid feed pump: L-6050 Hitachi High-Technologies Corporation UV-Vis detector: L-3000 Hitachi High-Technologies Corporation Column: Gelpack (registered trademark) GL-A160S / GL-A150S Hitachi Chemical Co., Ltd.
Eluent: THF (for HPLC, without stabilizer) Wako Pure Chemical Industries, Ltd.
Flow rate: 1 mL / min
Column temperature: Room temperature Molecular weight standard: Standard polystyrene

<Charge transporting polymer 2>
In a three-necked round bottom flask, monomer B2 (4.0 mmol), monomer L1 (10.0 mmol), monomer T1 (8.0 mmol), and toluene (87.3 mL), methyltri-n-octylammonium chloride (134. 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 2 was prepared in the same manner as the charge transporting polymer 1.

  The resulting charge transporting polymer 2 had a number average molecular weight of 39,600 and a weight average molecular weight of 111,600. The charge transporting polymer 2 has a structural unit B2, a structural unit L1, and a structural unit T1, and the proportion (molar ratio) of each structural unit was 18.1%, 45.6%, and 36.3%. It was.

<Charge transporting polymer 3>
In a three-necked round bottom flask, the monomer B2 (4.0 mmol), the monomer L1 (10.0 mmol), the following monomer T2 (8.0 mmol), toluene (78.3 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 3 was prepared in the same manner as the charge transporting polymer 1.

The number average molecular weight of the obtained charge transporting polymer 3 was 21,600, and the weight average molecular weight was 86,200. The charge transporting polymer 3 has a structural unit B2, a structural unit L1, and a structural unit T2, and the proportion (molar ratio) of each structural unit was 18.2%, 45.6%, and 36.2%. It was.

<Charge transporting polymer 4>
In a three-necked round bottom flask, the following monomer B3 (4.0 mmol), monomer L1 (10.0 mmol), monomer T2 (8.0 mmol), toluene (90.4 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 4 was prepared in the same manner as the charge transporting polymer 1.

  The resulting charge transporting polymer 4 had a number average molecular weight of 11,400 and a weight average molecular weight of 49,000. The charge transporting polymer 4 has a structural unit B3, a structural unit L1, and a structural unit T2, and the proportion (molar ratio) of each structural unit was 18.0%, 45.3%, and 36.7%. It was.

<Charge transporting polymer 5>
In a three-necked round bottom flask, the monomer B2 (4.0 mmol), the monomer L1 (10.0 mmol), the following monomer T3 (8.0 mmol), and toluene (54.1 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 5 was prepared in the same manner as the charge transporting polymer 1.

  The number average molecular weight of the obtained charge transporting polymer 5 was 14,300, and the weight average molecular weight was 45,300. The charge transporting polymer 5 has a structural unit B2, a structural unit L1, and a structural unit T3, and the proportion (molar ratio) of each structural unit was 18.1%, 45.6%, and 36.4%. It was.

<Charge transporting polymer 6>
In a three-necked round bottom flask, the following monomer B4 (4.0 mmol), monomer L1 (10.0 mmol), monomer T3 (8.0 mmol), toluene (62.4 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 6 was prepared in the same manner as the charge transporting polymer 1.

  The number average molecular weight of the obtained charge transporting polymer 6 was 20,700, and the weight average molecular weight was 65,600. The charge transporting polymer 6 has a structural unit B4, a structural unit L1, and a structural unit T3, and the proportion (molar ratio) of each structural unit was 18.1%, 45.3%, and 36.6%. It was.

<Charge transporting polymer 7>
In a three-necked round bottom flask, the monomer B2 (4.0 mmol), the monomer L1 (10.0 mmol), the following monomer T4 (8.0 mmol), toluene (54.1 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 7 was prepared in the same manner as the charge transporting polymer 1.

  The number average molecular weight of the obtained charge transporting polymer 7 was 19,500, and the weight average molecular weight was 43,900. The charge transporting polymer 7 has a structural unit B2, a structural unit L1, and a structural unit T4, and the proportion (molar ratio) of each structural unit was 18.3%, 45.5%, and 36.2%. It was.

<Charge transporting polymer 8>
In a three-necked round bottom flask, the monomer B3 (4.0 mmol), the monomer L1 (10.0 mmol), the following monomer T5 (8.0 mmol), and toluene (62.4 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 8 was prepared in the same manner as the charge transporting polymer 1.

  The number average molecular weight of the obtained charge transporting polymer 8 was 22,800, and the weight average molecular weight was 76,100. The charge transporting polymer 8 has a structural unit B4, a structural unit L1, and a structural unit T5, and the proportion (molar ratio) of each structural unit was 18.3%, 45.2%, and 36.5%. It was.

<Charge transporting polymer 9>
In a three-necked round bottom flask, the monomer B2 (4.0 mmol), the monomer L1 (10.0 mmol), the monomer T5 (8.0 mmol), and toluene (54.1 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 9 was synthesized in the same manner as the charge transporting polymer 1 was synthesized.

  The number average molecular weight of the obtained charge transporting polymer 9 was 22,600, and the weight average molecular weight was 60,500. The charge transporting polymer 9 has a structural unit B2, a structural unit L1, and a structural unit T5, and the proportion (molar ratio) of each structural unit was 18.4%, 45.4%, and 36.2%. It was.

<Charge transporting polymer 10>
In a three-necked round bottom flask, the following monomer B3 (4.0 mmol), monomer L1 (10.0 mmol), monomer T4 (8.0 mmol), toluene (62.4 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 10 was prepared in the same manner as the charge transporting polymer 1.

  The resulting charge transporting polymer 10 had a number average molecular weight of 8,200 and a weight average molecular weight of 48,400. The charge transporting polymer 10 has a structural unit B3, a structural unit L1, and a structural unit T4, and the proportion (molar ratio) of each structural unit was 18.1%, 45.5%, and 36.4%. It was.

<Charge transporting polymer 11>
In a three-necked round bottom flask, the monomer B1 (4.0 mmol), the monomer L1 (10.0 mmol), the following monomer T6 (8.0 mmol), and toluene (62.4 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 11 was prepared in the same manner as the charge transporting polymer 1.

  The obtained charge transporting polymer 11 had a number average molecular weight of 25,100 and a weight average molecular weight of 140,400. The charge transporting polymer 11 has a structural unit B1, a structural unit L1, and a structural unit T6, and the proportion (molar ratio) of each structural unit was 18.1%, 45.3%, and 36.6%. It was.

<Charge transporting polymer 12>
In a three-necked round bottom flask, the monomer B2 (4.0 mmol), the monomer L1 (10.0 mmol), the monomer T6 (8.0 mmol), and toluene (54.1 mL), methyltri-n-octylammonium chloride (134 4 mg), and further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 12 was prepared in the same manner as the charge transporting polymer 1.

  The number average molecular weight of the obtained charge transporting polymer 12 was 18,800, and the weight average molecular weight was 66,300. The charge transporting polymer 12 has a structural unit B2, a structural unit L1, and a structural unit T6, and the proportion (molar ratio) of each structural unit was 18.1%, 45.6%, and 36.4%. It was.

<Charge transporting polymer 13>
In a three-necked round bottom flask, the monomer B1 (2.0 mmol), the monomer B2 (2.0 mmol), the monomer L1 (10.0 mmol), the monomer T1 (2.8 mmol), the monomer T6 (5.2 mmol) And toluene (54.1 mL) and methyltri-n-octylammonium chloride (134.4 mg) were added, and a further prepared Pd catalyst solution (2.0 mL) was added. Thereafter, the charge transporting polymer 13 was prepared in the same manner as the charge transporting polymer 1.

  The number average molecular weight of the obtained charge transporting polymer 13 was 54,100, and the weight average molecular weight was 167,100. The charge transporting polymer 13 has a structural unit B1, a structural unit B2, a structural unit L1, a structural unit T1, and a structural unit T6. The proportion (molar ratio) of each structural unit is 9.1%, 9.1. %, 45.3%, 12.7%, and 23.8%.

2. Preparation and evaluation of organic HOD element (Example 1, Reference Examples 1A and 1B)
<1> Production of organic HOD element Charge transporting polymer 1 (5.0 mg) and charge transporting polymer 2 (5.0 mg) prepared above, the following electron-accepting compound 1 (0.1 mg), toluene ( 2.3 ml) was prepared.
In a nitrogen atmosphere, the above ink composition was spin-coated at 3000 rpm on a glass substrate patterned with ITO to a width of 1.6 mm, and then a glass substrate having a coating film (organic layer) was placed on a hot plate and air Inside, the said organic layer was hardened by heating for 30 minutes at the temperature of 200 degreeC.

  The substrate having the organic layer (hole injection layer) made of the cured coating film obtained as described above is transferred into a vacuum vapor deposition machine, and Al (100 nm) is formed on the organic layer of the substrate by a vapor deposition method. Then, a sealing process was performed to produce an organic HOD (Hole Only Device).

<2> Evaluation of HOD When a voltage was applied to the produced organic HOD, it was found that current flowed, and it was confirmed that the organic layer had a hole injection function. For the organic HOD, the current density at a driving voltage of 2.0 V was measured. The results are shown in Table 1.
Further, as Reference Example 1A and Reference Example 1B, an ink composition was prepared in the same manner as described above using 10.0 mg of the charge transporting polymer 1 alone or 10.0 mg of the charge transporting polymer 2 alone. Next, an organic HOD was prepared using each ink composition, and the current density of the obtained organic HOD was measured in the same manner as described above. The results are shown in Table 1. Further, the relationship between the blending ratio of the charge transporting polymer of Example 1 and the current density was graphed. A graph is shown in FIG.

(Comparative Example 1 and Reference Comparative Examples 1A and 1B)
In Example 1, Reference Examples 1A and 1B, the charge transporting polymers 1 and 2 in the ink composition used for forming the organic layer (hole injection layer) of the organic HOD each have a polymerizable functional group. Ink compositions shown in Table 2 were prepared in place of the charge transporting polymers 11 and 12 having no charge. Next, using each ink composition, an organic HOD was prepared in the same manner as in Example 1 and Reference Examples 1A and 1B, and the current density of the obtained organic HOD was measured in the same manner as described above. These results are shown in Table 2. Moreover, it graphed about the relationship between the compounding ratio of the charge transportable polymer of the comparative example 1, and current density. A graph is shown in FIG.

(Comparative Example 2)
In Example 1, the charge transporting polymers 1 and 2 in the ink composition used to form the organic layer (hole injection layer) of the organic HOD were blended with the charge transporting polymer 13 (10.0 mg). Instead, an ink composition was prepared. Next, an organic HOD was produced in the same manner as in Example 1, and then the current density was measured. The results are shown in Table 2. Further, the relationship between the charge transporting polymer blending ratio and the current density was graphed. A graph is shown in FIG. The charge transporting polymer 13 is a polymer having in its molecule the combination of monomers B1 and B2, T1 and T6 used in the charge transporting polymers 1 and 2 of Example 1.

(Examples 2-1 to 2-3 and Reference Examples 2A and 2B)
In Example 1, Reference Examples 1A and 1B, the charge transporting polymers 1 and 2 in the ink composition used for forming the organic layer (hole injection layer) of the organic HOD are shown in Table 3. Instead of blending polymers 3 and 4, respective ink compositions were prepared.
Next, in the same manner as in Example 1, an organic HOD was prepared using each ink composition, and the current density was measured. The results are shown in Table 3. Moreover, it graphed about the relationship between the compounding ratio of the charge transportable polymer of Examples 2-1 to 2-3, and current density. The graph is shown in FIG.

(Examples 3 to 5 and Reference Examples 3A, 3B, 4A, 4B, 5A, 5B)
The charge transporting polymers 1 and 2 in the ink composition used to form the organic layer (hole injection layer) of organic HOD in Example 1 and Reference Examples 1A and 1B are shown in Tables 4 and 5, respectively. Instead of blending the charge transporting polymer, each ink composition was prepared.
Next, in the same manner as in Example 1, an organic HOD was prepared using each ink composition, and the current density was measured. The results are shown in Tables 4 and 5. Moreover, it graphed about the relationship between the compounding ratio of the charge transport polymer of Examples 3-5, and an electric current density. The graph is shown in FIG.

As can be seen from the numerical values shown in Tables 1 to 5 and the graphs shown in FIGS. 2 to 4, in Examples 1 to 5, according to the change in the blend ratio of the charge transporting polymer in the ink composition. It can be seen that the current density of the organic HOD (conductivity of the organic layer) changes.
More specifically, as can be seen from the graph of FIG. 2, the current density values of the organic HODs formed from the ink composition of Example 1 are shown as Reference Examples 1A and 1B, respectively. The value of the organic HOD formed by using the ink composition using a single ink generally agrees with the linear value obtained from the current density value. As can be seen from the graphs of FIGS. 3 and 4, the same tendency is observed for Examples 2 to 5.
On the other hand, as can be seen from the graph of FIG. 2, in Comparative Example 1 in which the charge transporting polymer does not have a polymerizable functional group in the ink composition, each of the polymers shown as Reference Examples 1A and 1B is used alone. It is a value lower than the value on the straight line obtained from the value of the current density of the organic HOD formed using. Comparative Example 2 is an ink composition containing a homopolymer having 50% of the structure of charge transporting polymers 1 and 2 as the main skeleton. Comparative Example 2 is presumed to have a value closer to that of Example 1 than Comparative Example 1 because the polymer has a structure similar to that of Example 1 in the molecule, but still the current density of Example 1 It can be seen that the value is lower than the value of, and does not necessarily match the value on the straight line.
Based on the above, a charge transport layer is formed using a charge transport material containing two or more kinds of charge transport polymers capable of forming a bond between polymers, or an ink composition containing the material and a solvent. This shows that the conductivity of the charge transport layer can be easily controlled.

  As mentioned above, the effect by embodiment of this invention was shown along the Example. However, the present invention is not limited to the charge transporting polymer used in the examples. Similarly, when other polymers capable of forming a bond between the charge transporting polymers are used, the conductivity of the charge transporting layer is similarly determined. Can be easily controlled.

DESCRIPTION OF SYMBOLS 1 Light emitting layer 2 Anode 3 Hole injection layer 4 Cathode 5 Electron injection layer 6 Hole transport layer 7 Electron transport layer 8 Substrate

Claims (15)

  A method for controlling the conductivity of a charge transport layer, comprising forming the charge transport layer using a charge transport material containing two or more polymerizable charge transport polymers.   The charge transporting polymer has a first charge transporting polymer having at least one first polymerizable functional group at a terminal, and at least one second polymerizable functional group at a terminal, and the first And a second charge transporting polymer having a different charge transporting ability, wherein the first polymerizable functional group and the second polymerizable functional group can form a bond with each other. The method according to 1.   The method according to claim 2, wherein the first polymerizable functional group and the second polymerizable functional group have different structures.   The method according to claim 2 or 3, wherein the first polymerizable functional group is a conjugated diene and the second polymerizable functional group is a dienophile.   The charge transporting material further contains a polymerization initiator, and the first polymerizable functional group and the second polymerizable functional group are each a cyclic ether group having three or more members. The method according to 2 or 3.   The two or more polymerizable charge transporting polymers are each independently at least one selected from the group consisting of a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, benzene structure, and fluorene structure. 6. A method according to any one of the preceding claims comprising a seed structure.   The method according to claim 1, wherein the charge transporting material is used as a hole injecting material or a hole transporting material.   The method according to claim 1, wherein the charge transport layer is formed using an ink composition containing the charge transport material and a solvent.   An organic electronic device comprising: a charge transporting material containing two or more polymerizable charge transporting polymers; or a charge transporting layer formed using an ink composition comprising the charge transporting material and a solvent.   Organic electroluminescence comprising a charge transporting material comprising two or more polymerizable charge transporting polymers, or a charge transporting layer formed using an ink composition comprising said charge transporting material and a solvent element.   The organic electroluminescent element according to claim 10, further comprising a flexible substrate.   The organic electroluminescent element according to claim 11, wherein the flexible substrate includes a resin film.   The display element provided with the organic electroluminescent element of any one of Claims 10-12.   The illuminating device provided with the organic electroluminescent element of any one of Claims 10-12.   A display device comprising the illumination device according to claim 14 and a liquid crystal element as display means.

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