JP2017059718A - Organic electronics material, ink composition including the same, organic electronics device, and electroluminescent device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic electronics material and an ink composition which enable the enhancement of an organic electronics device and an organic EL device in device characteristics including a light emission efficiency and an emission lifetime.SOLUTION: A charge transport polymer including a structural unit of a valence of 3 or greater, which consists of aromatic hydrocarbon, is arranged and used as an organic electronics material.SELECTED DRAWING: Figure 1

Description

  Embodiments of the present invention relate to organic electronic materials and ink compositions containing the materials. Moreover, other embodiment of this invention is related with the organic electronics element and organic electroluminescent element which are produced using the said ink composition.

  Organic electronics elements are elements that perform electrical operations using organic substances, and are expected to exhibit features such as energy saving, low cost, and flexibility, and are attracting attention as a technology that can replace conventional inorganic semiconductors based on silicon. ing.

  Examples of the organic electronics element include an organic electroluminescence element (hereinafter also referred to as “organic EL element”), an organic photoelectric conversion element, an organic transistor, and the like.

  Among organic electronics elements, organic EL elements are attracting attention as applications for large-area solid-state light sources as an alternative to incandescent lamps and gas-filled lamps, for example. 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, low molecular organic EL elements and polymer organic EL elements, from the organic materials used. So far, various studies have been conducted on both elements in order to improve element characteristics such as luminous efficiency and element lifetime.
For example, a method is known in which device characteristics are improved by multilayering an organic layer of an organic EL device. In the low molecular weight organic EL element, a low molecular weight organic material is used, and film formation is mainly performed according to a vacuum deposition method. Therefore, multilayering can be easily achieved by performing vapor deposition while sequentially changing the organic material to be used.
On the other hand, in a polymer type organic EL element, a high molecular weight organic material is used, and film formation is performed according to a wet process such as printing or inkjet. High-molecular organic EL elements can be formed by simple methods such as printing and ink-jet as compared with low-molecular organic EL elements that require film formation in a vacuum system. It is expected as an indispensable element for organic EL displays. However, when a multilayer organic layer is produced according to a wet process, the lower layer is dissolved when the upper layer is applied, and the multilayering tends to be difficult.

On the other hand, there are several reports on polymer-type organic EL devices having multiple organic layers. Non-Patent Document 1 discloses a device having a three-layer structure using compounds having greatly different solubilities. Patent Document 1 discloses an element having a three-layer structure in which a layer called an interlayer is introduced on PEDOT: PSS. Furthermore, Non-Patent Documents 2 to 4 and Patent Document 2 describe a device using a siloxane compound or a compound containing a polymerizable functional group such as an oxetane group and a vinyl group for the purpose of insolubilizing a thin film with respect to a solvent. Disclosure.
However, in particular, when water-soluble PEDOT: PSS is used, it is necessary to remove moisture remaining in the thin film because the element is easily deteriorated by moisture. Also, when a siloxane compound is used, the compound is unstable with respect to moisture in the air, and the device tends to deteriorate. Thus, in the field of polymer organic EL devices, further improvements in device characteristics such as light emission efficiency and device life are required.

  In the first place, in order to manufacture a polymer type organic EL device having excellent device characteristics by a simple method, a high molecular weight organic material suitable for a wet process is required, and the properties of the organic material should be further improved. is necessary. Among the characteristics, in order to improve the light emission efficiency, for example, an organic material having a wide band gap is desired as a hole transport material. In contrast, Patent Document 3 discloses a compound in which two fluorenyl groups are introduced with respect to one phenyl group in a triphenylamine structure. More specifically, the present invention relates to a compound in which two fluorenyl groups are introduced relative to each other in a meta position relative to a phenyl group. Patent Document 3 discloses that such a compound can provide a wide band gap while ensuring high mobility due to the fluorenyl group and high Tg (glass transition temperature). However, since the disclosed compounds are low molecular weight compounds, it is difficult to perform wet processes using such compounds.

JP 2007-1119763 A International Publication No. 2008/010487 JP 2007-291064 A

Y. Goto, T. Hayashida, M. Noto, IDW '04 Proceedings of The 11th International Display Workshop, 1343-1346 (2004) H. Yan, P. Lee, N. R. Armstrong, A. Graham, G. A. Evemenko, P. Dutta, T. J. Marks, J. Am. Chem. Soc., 127, 3172-4183 (2005) E. Bacher, M. Bayerl, P. Rudati, N. Reckfuss, C. David, K. Meerholz, O. Nuyken, Macromolecules, 38, 1640 (2005) M. S. Liu, Y. H. Niu, J. W. Ka, H. L. Yip, F. Huang, J. Luo, T. D. Wong, A. K. Y. Jen, Macromolecules, 41, 9570 (2008)

  As described above, in the field of polymer organic EL devices, development of high molecular weight organic materials suitable for wet processes is desired for further improvement of device characteristics. For example, it is desired to realize an organic electronic material having a wide band gap and capable of improving the light emission efficiency and the light emission lifetime. Therefore, an object of the embodiment of the present invention is to provide an organic electronic material and an ink composition that can improve device characteristics such as light emission efficiency and light emission lifetime of an organic EL device. Another object of the present invention is to provide an organic electronic device and an organic EL device having excellent device characteristics using the organic electronic material and the ink composition.

  As a result of intensive studies, the present inventors have found that a charge transporting polymer having a specific structural unit is suitable as an organic electronic material, and have completed the present invention. That is, the present invention relates to the matters described below.

One embodiment of the present invention is an organic electronic material including a charge transporting polymer having a structure branched in three or more directions, wherein the charge transporting polymer is an aromatic carbon hydrogen which may have a substituent. The present invention relates to an organic electronic material having a trivalent or higher valent structural unit.
Here, the charge transporting polymer further includes a divalent structural unit, and the divalent structural unit includes a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, benzene structure, and fluorene. It is preferably selected from the group consisting of structures. In one embodiment, the charge transporting polymer preferably includes a partial structure in which three or more divalent structural units are bonded to one of the trivalent or higher structural units. In one embodiment, the charge transporting polymer preferably has one or more polymerizable functional groups in the molecule.

One embodiment of the present invention relates to an ink composition comprising an organic electronics material and a solvent.
One embodiment of the present invention relates to an organic electronic device having a substrate and an organic layer formed using the ink composition. Here, the substrate is preferably a resin film.
One embodiment of the present invention relates to an organic electroluminescent device having an organic layer formed using the ink composition. Here, the organic layer is preferably a hole transport layer.

  According to the organic electronic material and the ink composition which are the embodiments of the present invention, it is possible to improve device characteristics such as light emission efficiency and device lifetime of the organic EL device. According to another embodiment of the present invention, an organic electronics element and an organic EL element having excellent element characteristics can be provided using the organic electronics material and the ink composition.

It is typical sectional drawing which shows one Embodiment of the organic EL element of this invention.

Hereinafter, embodiments of the present invention will be described.
<Organic electronics materials>
The organic electronic material of the present invention includes a charge transporting polymer having a charge transporting property and a structure branched in three or more directions. Since the charge transporting polymer has a branched structure in the molecule, the viscosity of the polymer solution is difficult to change with respect to the change in the molecular weight, and the molecular weight can be easily adjusted, and the durability of the organic electronics element can be improved. Is also easier. The organic electronic material may contain only one kind of the charge transporting polymer or two or more kinds. Hereinafter, embodiments of the charge transporting polymer will be described more specifically.

(Charge transporting polymer)
In the above charge transporting polymer, “a structure branched in three or more directions” means that the main chain is a chain having the largest degree of polymerization among various chains in one molecule of the charge transporting polymer. It means that there is one or more side chains having the same degree of polymerization or a lower degree of polymerization. In the present invention, the degree of polymerization indicates how many monomer units used for synthesizing the charge transporting polymer per molecule of the charge transporting polymer. In the present invention, the side chain is a chain different from the main chain of the charge transporting polymer and has at least one structural unit, and the other side is regarded as a substituent instead of a side chain.

  In the present invention, the charge transporting polymer includes a trivalent or higher valent structural unit B constituting the branched portion of the “structure branched in three or more directions” described above, and the structural unit B has a substituent. Or a tri- or higher valent structural unit B1 composed of only aromatic hydrocarbons. When the charge transporting polymer has the specific structural unit B1, the band gap is widened, and it is easy to improve various characteristics such as light emission efficiency and device lifetime. Hereinafter, the structural unit B1 will be specifically described.

(Structural unit B1)
In the “trivalent or higher structural unit B1 consisting only of aromatic hydrocarbons”, the term “trivalent or higher” means that there are 3 or more bonding sites with other structural units in the structural unit. The structural unit B1 is preferably hexavalent or less, more preferably trivalent or tetravalent. Further, “consisting only of aromatic hydrocarbon” means that a hetero element (for example, an element such as O, F, S, or N) is not introduced into the main skeleton of the trivalent or higher structural unit B1. . That is, the structural unit B1 has a main skeleton composed of only C and H, including at least one benzene ring. The structural unit B1 may be composed of two or more benzene rings and may contain a condensed ring structure such as naphthalene, but it is intended that the main skeleton does not contain a hetero element. That is, when two or more benzene rings are present in the structural unit B1, the structure unit B1 is intended to have a structure in which benzene rings are bonded to each other without intervening hetero elements, such as a biphenyl structure. In the structural unit B1, the benzene ring constituting the main skeleton may have a substituent. In this case, the main skeleton does not include a hetero element, but the substituent may include a hetero element.

Specific examples of the trivalent or higher structural unit B1 made of only the aromatic hydrocarbon include the following.

  In the above formulas, each R is independently a hydrogen atom or a substituent. The substituent is selected from the group consisting of a halogen atom, a linear, cyclic or branched alkyl group having 1 to 22 carbon atoms, an alkoxy group, an alkylcarbonyl group, and an alkylamide group, and an aryl group having 6 to 30 carbon atoms. It may be a selected substituent. Moreover, adjacent Rs may combine to form a ring. Here, when R is an aryl group, the aryl group may have a substituent. The substituent for the aryl group may be a substituent selected from an alkyl group, an alkoxyl group, an amino group, an imide group, a sulfo group, a carboxyl group, and a phosphonyl group.

  In one embodiment, preferably, R is a hydrogen atom or a halogen atom, a linear, cyclic or branched alkyl group, alkoxy group, alkylcarbonyl group, and alkylamide group having 1 to 8 carbon atoms. And a group selected from the group consisting of aryl groups having 6 to 12 carbon atoms. More preferably, R is a hydrogen atom.

  In one embodiment, the trivalent or higher structural unit B1 has a main skeleton composed of only one or more benzene rings which may have a substituent. However, it is preferable that a condensed ring structure such as naphthalene is not included in the structural unit from the viewpoint of obtaining a wide band gap. In one embodiment, the trivalent or higher structural unit B1 is more preferably composed of only 1 to 6 benzene rings which may have a substituent, and is composed of only 1 to 5 benzene rings. More preferably. The bond form of the benzene ring may be linear or non-linear.

Preferable specific examples of the trivalent or higher structural unit B1 include the following trivalent or tetravalent structural units having a benzene structure skeleton.

  Other examples include a trivalent or tetravalent structural unit having a triphenylbenzene skeleton composed of four benzene rings, and a trivalent structural unit is more preferable. More specifically, the following trivalent structural units having a triphenylbenzene skeleton are exemplified.

  In the formula, R may be a hydrogen atom or a substituent, as described above, and is preferably a hydrogen atom. The positions of the three binding sites in the triphenylbenzene skeleton are not particularly limited. In one embodiment, the structural unit B1 preferably has the structure shown below.

(Structure of charge transporting polymer)
In one embodiment, the charge transporting polymer includes the structural unit B1 as the trivalent or higher structural unit B constituting the branched portion, and further includes a monovalent structural unit T that forms at least a terminal portion. In another embodiment, the charge transporting polymer includes the structural unit B1 as the trivalent or higher structural unit B, and further includes a divalent structural unit L having charge transporting property and the monovalent structural unit T. Including. 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 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.

  Although not particularly limited, in one embodiment, the charge transporting polymer includes, as the trivalent or higher structural unit B, the trivalent or higher structural unit B1 composed only of an aromatic hydrocarbon. It is preferable to include a partial structure in which three or more divalent structural units L having charge transporting properties are bonded to one. Hereinafter, each structural unit will be specifically described.

(Structural unit B)
The structural unit B is a trivalent or higher structural unit that forms a branched portion in a charge transporting polymer having a structure branched in three or more directions. 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 a charge transporting property. In the present invention, the structural unit B includes at least a trivalent or higher structural unit B1 composed only of the aromatic hydrocarbon, and includes a trivalent or higher structural unit B2 having other charge transport properties as necessary. But you can.

  From the viewpoint of obtaining effects such as improvement of durability and luminous efficiency, in one embodiment, the proportion of the structural unit B1 in the charge transporting polymer is preferably 1 mol% or more, more preferably 3 mol% or more, and 5 mol%. The above is most preferable. On the other hand, from the viewpoint of further improving the charge transportability of the charge transportable polymer, the charge transportable polymer preferably includes another structural unit having excellent charge transportability in addition to the structural unit B1. From such a viewpoint, in one embodiment, the proportion of the structural unit B1 in the charge transporting polymer is preferably 95 mol% or less, more preferably 90 mol% or less, and most preferably 85 mol% or less.

  By using an organic electronic material containing a charge transporting polymer in which the proportion of the structural unit B1 is within the above range, an organic EL device having excellent durability and luminous efficiency can be easily obtained. In addition, the charge transporting polymer adjusted so that the proportion of the structural unit B1 is within the above range is preferable in that it has an appropriate molecular weight as an organic electronic material.

  The proportion of the structural unit B1 in the charge transporting polymer can be achieved by adjusting the amount of the monomer compound having the structural unit B1 when preparing the charge transporting polymer. The proportion of the structural unit B1 can be calculated from the ratio (molar ratio) of the monomer compound having the structural unit B1 to the total charged amount of various monomer compounds used as raw materials. The proportion of the structural unit B1 can also be calculated from the integral ratio of the characteristic peaks by measuring the NMR of the charge transporting polymer.

  In one embodiment, the charge transporting polymer may include other trivalent or higher structural unit B2 as the trivalent or higher structural unit B in addition to the structural unit B1. Here, the ratio of the structural unit B1 to the total amount of the structural units B1 and B2 is preferably 10% or more, more preferably 20% or more, and further preferably 30% or more. By adjusting the proportion of the structural unit B1 within the above range, in addition to excellent charge transportability, it is easy to obtain the advantage of the structural unit B1 made of only aromatic hydrocarbons. The proportion of the structural unit B1 in the trivalent or higher structural unit B may be 100%.

Specific examples of the structural unit B2 include the following. However, the structural unit B2 is not limited to the following.

  W represents a trivalent linking group, for example, a C2-C30 heteroarene triyl group. 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 a 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, and for example, from a group having one or more hydrogen atoms in R (excluding a group containing a polymerizable functional group) in the structural unit L described later, Examples thereof include a divalent group excluding a hydrogen atom. Z represents either 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 described later.

(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, biphenylene structure, terphenylene 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 A thiophene structure, a benzoxazole structure, a benzooxadiazole structure, a benzothiazole structure, a benzothiadiazole structure, a benzotriazole structure, and one or more of these It is selected from a structure including more species. 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 group consisting of a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, bithiophene structure, benzene structure, and fluorene structure from the viewpoint of obtaining excellent hole transport properties. Is preferably selected from. In one embodiment, the structural unit L is more preferably selected from a substituted or unsubstituted aromatic amine structure, carbazole structure, and a structure including one or more of these.
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. However, 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 a polymerizable functional group described later. Selected from the group consisting of containing groups. 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. Ar is preferably an arylene group, more preferably a phenylene group. 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.

  Examples of the aromatic hydrocarbon include a single ring, a condensed ring, or a polycycle in which two or more selected from a single ring and a condensed ring are bonded via a single bond. Examples of the aromatic heterocycle include a single ring, a condensed ring, or a polycycle in which two or more selected from a monocycle and a condensed ring are bonded via a single bond.

(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, and is selected from, for example, 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 is preferably a substituted or unsubstituted aromatic hydrocarbon structure from the viewpoint of imparting durability without deteriorating charge transportability, and is preferably a substituted or unsubstituted benzene structure. A structure is more preferable. In another embodiment, as will be described later, when the charge transporting polymer has a polymerizable functional group at the terminal portion, the structural unit T has a polymerizable structure (that is, polymerizable such as a pyrrole-yl group). Functional group). The structural unit T may have the same structure as the structural units L and / or B, or may have a different structure.

Specific examples of the structural unit T include the following. However, the structural unit T is not limited to the following.

  R is the same as R in the structural unit L. When the charge transporting polymer has a polymerizable functional group at the terminal portion, preferably at least one of R is a group containing a polymerizable functional group.

(Polymerizable functional group)
In one embodiment, from the viewpoint of curing by a polymerization reaction and changing the solubility in a solvent, the charge transporting polymer preferably has at least one polymerizable functional group in the molecule. The “polymerizable functional group” refers to a functional group that can form a bond with each other by applying heat and / or light.

  The polymerizable functional group includes a group having a carbon-carbon multiple bond (for example, vinyl group, allyl group, butenyl group, ethynyl group, acryloyl group, acryloyloxy group, acryloylamino group, methacryloyl group, methacryloyloxy group, methacryloylamino group). Groups, vinyloxy groups, vinylamino groups, etc.), groups having a small ring (eg, cyclic alkyl groups such as cyclopropyl groups, cyclobutyl groups; cyclic ether groups such as epoxy groups (oxiranyl groups), oxetane groups (oxetanyl groups), etc. Diketene group; episulfide group; lactone group; lactam group, etc.), heterocyclic group (for example, furan-yl group, pyrrol-yl group, thiophen-yl group, silole-yl group) and the like. As the polymerizable functional group, a vinyl group, an acryloyl group, a methacryloyl group, an epoxy group, and an oxetane group are particularly preferable, and from the viewpoint of reactivity and characteristics of the organic electronics element, a vinyl group, an oxetane group, or an epoxy group is more preferable. preferable.

  From the viewpoint of increasing the degree of freedom of the polymerizable functional group and facilitating the polymerization reaction, it is preferable that the main skeleton of the charge transporting polymer and the polymerizable functional group are connected by an alkylene chain. In addition, for example, when an organic layer is formed on an electrode, it is connected with a hydrophilic chain such as an ethylene glycol chain or a diethylene glycol chain from the viewpoint of improving the affinity with a hydrophilic electrode such as ITO. preferable. Further, from the viewpoint of facilitating the preparation of the monomer used for introducing the polymerizable functional group, the charge transporting polymer is polymerized with the end of the alkylene chain and / or the hydrophilic chain, that is, with these chains. An ether bond or an ester bond may be present at the connecting portion with the functional group and / or the connecting portion between these chains and the skeleton of the charge transporting polymer. The above-mentioned “group containing a polymerizable functional group” means a polymerizable functional group itself or a group obtained by combining a polymerizable functional group with an alkylene chain or the like. As the group containing a polymerizable functional group, for example, a group exemplified in International Publication No. WO2010 / 140553 can be suitably used.

Although it does not specifically limit, In one Embodiment, the following is mentioned as a specific example of the preferable structural unit T.

  The polymerizable functional group may be introduced into the terminal part (that is, the structural unit T) of the charge transporting polymer, or may be introduced into a part other than the terminal part (that is, the structural unit L or B). And may be introduced into both of the portions other than the 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.

  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 impeding charge transportability, it is preferable that the amount contained in the charge transport 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.

(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. The number average molecular weight is preferably 500 or more, more preferably 1,000 or more, and still more preferably 2,000 or more, from the viewpoint of excellent charge transportability. The number average molecular weight is preferably 1,000,000 or less, more preferably 100,000 or less, and more preferably 50,000 from the viewpoint of maintaining good solubility in a solvent and facilitating the 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.

  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 B contained in the charge transporting polymer is preferably 1 mol% or more, more preferably 5 mol% or more, more preferably 10 mol%, based on the total structural unit, from the viewpoint of improving the durability of the organic electronics element. The above 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. Here, the ratio of the structural unit B means the sum of the trivalent or higher structural unit B1 made of only aromatic hydrocarbons and any other trivalent or higher structural unit B2 having any charge transporting property.

  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 has a polymerizable functional group, the proportion of the polymerizable functional group is preferably 0.1 mol% or more based on the total structural unit from the viewpoint of efficiently curing the charge transporting polymer, 1 mol% 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.

  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. Here, the ratio of the structural unit B means the sum of the trivalent or higher structural unit B1 made of only aromatic hydrocarbons and any other trivalent or higher structural unit B2 having any charge transporting property.

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 one embodiment, the charge transporting polymer has a trivalent or higher structural unit B1 made of only aromatic hydrocarbons, a divalent structural unit L having charge transporting properties, and a monovalent structural unit T. Here, the divalent structural unit L preferably has at least one structure selected from the group consisting of an aromatic amine structure, a carbazole structure, and a thiophene structure. Especially, it is preferable that the structural unit L has an aromatic amine structure. The aromatic amine structure is preferably a triarylamine structure, more preferably a triphenylamine structure. The monovalent structural unit T preferably has a polymerizable functional group at the terminal.

(Method for producing charge transporting polymer)
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 of International Publication No. WO2010 / 140553 can be referred to.

(Raw material monomer compound)
Although not particularly limited, when a charge transporting polymer is prepared using the Suzuki coupling reaction, a monomer compound capable of inducing each of the structural units B, L, and T can be used as a raw material. An example of a combination of raw material monomers that can be used is shown.

  In the illustration of the monomer L, R is the same as R described above for the structural unit L. In one embodiment of the monomer L, R is a linear or branched alkyl group having 1 to 8 carbon atoms, preferably a linear alkyl group having 1 to 4 carbon atoms. In addition, in the monomers B, L and T, the positions of reactive functional groups such as bromo group and boronic acid are not particularly limited. When a reactive functional group is located in para position, it is preferable at the point from which higher reactivity is obtained. According to the combination of the monomers, a polymer in which structural units L, B, and T derived from each monomer are bonded to each other is obtained by a reaction between a boronic acid group and a bromo group in the monomer. Each monomer may have a combination of reactive functional groups that can form a bond by reaction with each other, and may have a structure in which a boronic acid group and a bromo group are interchanged with each other. , A boronic acid ester, or a halogen group other than a bromo group.

[Dopant]
When an organic electronic material is used to construct an organic electronic element, the organic electronic material may further contain a known additive. In one embodiment, the organic electronic material may further contain a dopant. The dopant is not particularly limited as long as it can be added to the organic electronic material to develop a doping effect and improve the charge transport property. 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 in the organic electronic 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) salts having a perfluoroalkyl anions etc., a salt with a conjugate base of the protonic acid as an anion. Examples of the halogen _{compound, Cl 2, Br 2, I} 2, ICl, ICl 3, IBr, IF and the like; [pi conjugated compound 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 n-type doping is an electron donating compound, for example, alkali metals such as Li and Cs; alkaline earth metals such as Mg and Ca; alkali metals such as LiF and Cs ₂ CO ₃ and / or Examples include alkaline earth metal salts; metal complexes; electron-donating organic compounds.

  When the charge transporting polymer has a polymerizable functional group, it is preferable to use a compound that can act as a polymerization initiator for the polymerizable functional group as a dopant in order to facilitate the change in solubility of the organic layer.

[Other optional ingredients]
The organic electronic material may further contain a charge transporting low molecular weight compound, another polymer, and the like.

[Content]
The content of the charge transporting polymer is preferably 50% by weight or more, more preferably 70% by weight or more, and further preferably 80% by weight or more based on the total weight of the organic electronic material from the viewpoint of obtaining good charge transporting properties. preferable. It may be 100% by mass.

  When the dopant is contained, the content is preferably 0.01% by mass or more, and 0.1% by mass or more with respect to the total mass of the organic electronic material from the viewpoint of improving the charge transport property of the organic electronic material. More preferred is 0.5% by mass or more. Moreover, from a viewpoint of maintaining favorable film formability, 50 mass% or less is preferable with respect to the total mass of the organic electronic material, 30 mass% or less is more preferable, and 20 mass% or less is still more preferable.

<Ink composition>
The ink composition which is an embodiment of the present invention contains the organic electronic material of the above embodiment and a solvent capable of dissolving or dispersing the material. By using the ink composition, the 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.

[Polymerization initiator]
When the charge transporting polymer has a polymerizable functional group, the ink composition preferably contains a polymerization initiator. As the polymerization initiator, known radical polymerization initiators, cationic polymerization initiators, anionic polymerization initiators and the like can be used. From the viewpoint of easily preparing the ink composition, it is preferable to use a substance having both a function as a dopant and a function as a polymerization initiator. As such a substance, the said ionic compound is mentioned, for example.

[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. .

<Organic layer>
The organic layer which is embodiment of this invention is a layer formed using the organic electronics material or ink composition of the said embodiment. By using the ink composition, the organic layer can be favorably 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.

  When the charge transporting polymer has a polymerizable functional group, the solubility of the organic layer can be changed by advancing 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 of forming the organic layer, for example, the description of International Publication No. WO2010 / 140553 can be referred to.

  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>
The organic electronics element which is embodiment of this invention has the organic layer of the said embodiment at least. 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 including an anode and a cathode.

[Organic EL device]
The organic EL element which is embodiment of this invention has an organic layer of the said embodiment at least. 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 an 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 made of the organic layer of the above embodiment, a light emitting layer 1, an electron transport layer 7, The electron injection layer 5 and the cathode 4 are provided 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-formin 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 include polymers of the organic electronic materials, polyvinyl carbazole, polyphenylene, polyfluorene, derivatives thereof, and the like of the above embodiment. It is done.

  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.

[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, and carbodiimides. Fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, thiadiazole derivatives, benzimidazole derivatives, quinoxaline derivatives, aluminum complexes, and the like. Moreover, the organic electronic material of the said 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 preferably has 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.

[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. The combination of a plurality of emission colors is not particularly limited, but includes a combination containing three emission maximum wavelengths of blue, green and red, and two emission maximum wavelengths such as blue and yellow, yellow green and orange. The combination etc. which contain are mentioned. The emission color can be controlled by adjusting the type and amount of the light emitting material.

<Display element, lighting device, display device>
The display element which is embodiment of this invention is equipped with the organic EL element of the said 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, the illuminating device which is embodiment of this invention is equipped with the organic EL element of embodiment of this invention. Furthermore, the display apparatus which is embodiment of this invention is equipped with the illuminating device and the liquid crystal element as a display means. For example, the display device may be a display device using a known liquid crystal element as a display unit, that is, a liquid crystal display device, using the illumination device according to the embodiment of the present invention as a backlight.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to the following embodiment.

I. Preparation of organic electronics materials (Preparation of Pd catalyst)
In a glove box under a nitrogen atmosphere, tris (dibenzylideneacetone) dipalladium (73.2 mg, 80 μmol) was weighed into a sample tube at room temperature, anisole (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, anisole (5 ml) was added, and the mixture was stirred for 5 minutes. These solutions were mixed and stirred at room temperature for 30 minutes, and the resulting product was used as a catalyst.

(Preparation Example 1) Charge transporting polymer 1
In a three-necked round bottom flask, the following monomer 1 (5.0 mmol), monomer 2 (2.0 mmol), monomer 3 (4.0 mmol) and anisole (20 ml) were placed, and the Pd catalyst solution prepared earlier was further added. (7.5 ml) was added. After stirring these raw materials for 30 minutes, a 10% tetraethylammonium hydroxide aqueous solution (20 ml) was added. In addition, all the solvents used for reaction were used after deaerating for 30 minutes or more with a nitrogen bubble. The reaction mixture obtained as described above was heated and refluxed for 2 hours. All 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 suction filtered and washed with methanol-water (9: 1). The resulting precipitate was dissolved in toluene and reprecipitated from methanol. The obtained precipitate was suction filtered, dissolved in toluene, triphenylphosphine, polymer-bound on styrene-divine benzene copolymer (200 mg from 100 mg of polymer, polymer), and stirred overnight. After completion of the stirring, triphenylphosphine, polymer-bound on styrene-divinylbenzene copolymer and insoluble matter were removed by filtration, and the filtrate was concentrated by a rotary evaporator. The residue was dissolved in toluene and then reprecipitated from methanol-acetone (8: 3). The resulting precipitate was filtered by suction and washed with methanol-acetone (8: 3). The obtained precipitate was vacuum-dried to obtain 1.3 g of a charge transporting polymer 1.
The number average molecular weight of the obtained charge transporting polymer 1 was 8,900, and the mass average molecular weight was 52,300. The charge transporting polymer 1 has a structural unit L (derived from the monomer 1), a structural unit B1 (derived from the monomer 2), and a structural unit T (derived from the monomer 3). 5%, 18.2%, and 36.4%.

The number average molecular weight and the weight average molecular weight were measured by GPC (polyethylene conversion) using tetrahydrofuran (THF) as an eluent. The measurement conditions are as follows.
Liquid feed pump: L-6050 Hitachi High-Technologies UV-Vis detector: L-3000 Hitachi High-Technologies columns: 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

(Preparation Example 2) Charge transporting polymer 2
A charge transporting polymer 2 was obtained in the same manner as in Preparation Example 1 except that the monomer 2 in Preparation Example 1 was changed to the monomer 4 shown below. The number average molecular weight of the obtained charge transporting polymer 2 was 4000, and the mass average molecular weight was 14,000. The charge transporting polymer 2 has a structural unit L (derived from the monomer 1), a structural unit B1 (derived from the monomer 4), and a structural unit T (derived from the monomer 3). 5%, 18.2%, and 36.4%.

(Preparation Example 3) Charge transporting polymer 3
A charge transporting polymer 3 was obtained in the same manner as in Preparation Example 1 except that the monomer 2 in Preparation Example 1 was changed to the monomer 5 shown below. The number average molecular weight of the obtained charge transporting polymer 3 was 5500, and the mass average molecular weight was 47500. The charge transporting polymer 3 has a structural unit L (derived from the monomer 1), a structural unit B1 (derived from the monomer 5), and a structural unit T (derived from the monomer 3). 5%, 18.2%, and 36.4%.

(Preparation Example 4) Charge transporting polymer 4
A charge transporting polymer 4 was obtained in the same manner as in Preparation Example 1 except that the monomer 2 (2.0 mmol) of Preparation Example 1 was changed to the monomer 6 (1.5 mmol) shown below. The number average molecular weight of the obtained charge transporting polymer 4 was 2800, and the mass average molecular weight was 8100. The charge transporting polymer 4 has a structural unit L (derived from the monomer 1), a structural unit B1 (derived from the monomer 6), and a structural unit T (derived from the monomer 3). 6%, 14.3%, and 38.1%.

(Preparation Example 5) Charge transporting polymer 5
A charge transporting polymer 5 was obtained in the same manner as in Preparation Example 1 except that the monomer 2 in Preparation Example 1 was changed to the monomer 7 shown below. The number average molecular weight of the obtained charge transporting polymer 5 was 7800, and the mass average molecular weight was 31000. The charge transporting polymer 5 has a structural unit L (derived from the monomer 1), a structural unit B2 (derived from the monomer 7), and a structural unit T (derived from the monomer 3). 5%, 18.2%, and 36.4%.

II. Evaluation of Organic Electronics Material Various characteristics were examined using each of the charge transporting polymers 1 to 5 prepared above as an organic electronics material.
<Organic EL device>
In Examples 1 to 4 and Comparative Example 1 below, organic EL elements having a hole transport layer constituted by using the charge transport polymers 1 to 5 prepared previously were examined.

Example 1
An ink composition for a hole injection layer, comprising charge transporting polymer 5 (10.0 mg), the following compound 1 (0.5 mg) as a polymerization initiator, and toluene (2.3 mL) was prepared. In a nitrogen atmosphere, the ink composition was spin-coated at 3000 min ⁻¹ on a glass substrate on which ITO was patterned to a width of 1.6 mm. Subsequently, it heated for 10 minutes at the temperature of 220 degreeC on the hotplate, and the positive hole injection layer (30 nm) was formed by hardening a coating film.

Next, an ink composition for a hole transport layer, which is composed of the charge transport polymer 1 (20 mg) and toluene (2.3 mL) on the hole injection layer obtained by the above operation, is 3000 min ^−1. Spin coated with. Next, a hole transport layer (40 nm) was formed by heating and drying on a hot plate at a temperature of 180 ° C. for 10 minutes. Thus, a laminate of glass substrate / hole injection layer / hole transport layer was obtained.

Next, the laminate obtained as described above was transferred during vacuum deposition, and CBP: Ir (ppy) ₃ (94: 6, ₃₀ nm), BAlq (10 nm), Alq ₃ was formed on the hole transport layer. (30 nm), LiF (0.8 nm), Al (100 nm) were formed in this order by a vapor deposition method, and sealing treatment was performed to produce an organic EL element. The light emission efficiency and light emission lifetime (luminance half-life) of the obtained organic EL were evaluated using a luminance meter (Topcon, BM7) and a current voltmeter (YOKOGAWA / HEWLETT / PACKARD 4140B). Specifically, the light emission efficiency when the light emission luminance was set to 3000 cd / m ² and the time until the luminance was reduced by half were measured. The results are shown in Table 2.

(Example 2)
An organic EL device was produced in the same manner as Example 1 except that the charge transporting polymer 1 was changed to the charge transporting polymer 2 for the ink composition for the hole transporting layer of Example 1. The luminous efficiency of the obtained organic EL was evaluated in the same manner as in Example 1. The results are shown in Table 2.

(Example 3)
An organic EL device was produced in the same manner as Example 1 except that the charge transporting polymer 1 was changed to the charge transporting polymer 3 for the ink composition for the hole transporting layer of Example 1. The luminous efficiency of the obtained organic EL was evaluated in the same manner as in Example 1. The results are shown in Table 2.

Example 4
An organic EL device was produced in the same manner as in Example 1 except that the charge transporting polymer 1 was changed to the charge transporting polymer 4 for the ink composition for the hole transporting layer of Example 1. The luminous efficiency of the obtained organic EL was evaluated in the same manner as in Example 1. The results are shown in Table 2.

(Comparative Example 1)
An organic EL device was produced in the same manner as in Example 1 except that the charge transporting polymer 1 was changed to the charge transporting polymer 5 for the ink composition for the hole transporting layer of Example 1. The luminous efficiency of the obtained organic EL was evaluated in the same manner as in Example 1. The results are shown in Table 2.

  From comparison between Examples 1 to 4 and Comparative Example 1, it can be seen that according to the organic electronics material (charge transporting polymer) of the present invention, a highly efficient and long-life organic EL element can be produced. That is, by introducing a specific structural unit consisting only of an aromatic ring not containing a hetero element in addition to a structural unit having a charge transporting property in the molecule of the charge transporting polymer, the emission efficiency and the emission lifetime can be improved. You can see.

<Solvent resistance>
Using the layered structure of the hole injection layer / hole transport layer as a model, an embodiment in which the hole transport layer is formed using the charge transport polymers 1 to 4 previously prepared as the organic electronic material was studied. More specifically, in Examples 5 to 12 below, the ink composition containing the charge transporting polymers 1 to 4 is applied to the hole injection layer formed using the charge transporting polymer 5. The solvent resistance of the laminate obtained by film formation was evaluated.

(Example 5)
First, an ink composition 1 comprising a charge transporting polymer 5 (10.0 mg), the following compound 1 (0.5 mg) as a polymerization initiator, and toluene (2.3 mL) was prepared. This ink composition 1 was spin-coated on a quartz plate at 3000 rpm. Next, the first thin film was formed on the quartz plate by heating on a hot plate at 180 ° C. for 10 minutes.

Next, an ink composition 2A composed of charge transporting polymer 1 (10.0 mg) and toluene (2.3 mL) was prepared, and this ink composition 2A was spin-coated on the first thin film at 3000 rpm. . Next, a quartz plate / first thin film / second thin film laminate was obtained by heating on a hot plate at 180 ° C. for 10 minutes.
The obtained laminate was immersed in toluene for 1 minute and washed. The residual film ratio was measured from the ratio of absorbance (Abs) of the absorption maximum (λmax) in the UV-vis spectrum of the laminate before and after washing. The results are shown in Table 3.

(Example 6)
For the ink composition 2A of Example 5, an ink composition was prepared in the same manner as in Example 5 except that the charge transporting polymer 1 was changed to the charge transporting polymer 2, and a second thin film was formed. A laminate was obtained. About the obtained laminated body, it carried out similarly to Example 5, and measured the remaining film rate. The results are shown in Table 3.

(Example 7)
For the ink composition 2A of Example 5, an ink composition was prepared in the same manner as in Example 5 except that the charge transporting polymer 1 was changed to the charge transporting polymer 3, and a second thin film was formed. A laminate was obtained. About the obtained laminated body, it carried out similarly to Example 5, and measured the remaining film rate. The results are shown in Table 3.

(Example 8)
For the ink composition 2A of Example 5, an ink composition was prepared in the same manner as in Example 5 except that the charge transporting polymer 1 was changed to the charge transporting polymer 4, and a second thin film was formed. A laminate was obtained. About the obtained laminated body, it carried out similarly to Example 5, and measured the remaining film rate. The results are shown in Table 3.

Example 9
For the ink composition 2A of Example 5, the ink composition 2B comprising the charge transporting polymer 1 (10.0 mg), the compound 1 (0.5 mg) as a polymerization initiator, and toluene (2.3 mL) was added. Except for the change, a second thin film was formed in the same manner as in Example 5 to obtain a laminate. About the obtained laminated body, it carried out similarly to Example 5, and measured the remaining film rate. The results are shown in Table 3.

(Example 10)
For the ink composition 2B of Example 9, an ink composition was prepared in the same manner as in Example 9 except that the charge transporting polymer 1 was changed to the charge transporting polymer 2, and a second thin film was formed. A laminate was obtained. About the obtained laminated body, it carried out similarly to Example 9, and measured the remaining film rate. The results are shown in Table 3.

(Example 11)
For the ink composition 2B of Example 9, an ink composition was prepared in the same manner as in Example 9 except that the charge transporting polymer 1 was changed to the charge transporting polymer 3, and a second thin film was formed. A laminate was obtained. About the obtained laminated body, it carried out similarly to Example 9, and measured the remaining film rate. The results are shown in Table 3.

(Example 12)
For the ink composition 2B of Example 9, an ink composition was prepared in the same manner as in Example 9 except that the charge transporting polymer 1 was changed to the charge transporting polymer 4, and a second thin film was formed. A laminate was obtained. About the obtained laminated body, it carried out similarly to Example 9, and measured the remaining film rate. The results are shown in Table 3.

As is clear from Examples 5 to 12, it can be seen that when the charge transporting polymer has a polymerizable functional group in the molecule, the hole transporting layer is insolubilized and a high residual film ratio is obtained. From this, when a charge transporting polymer having a polymerizable functional group in the molecule is used, it becomes easier to form an organic layer by a wet process, and the upper layer is formed by a wet process, thereby enabling multilayering. I understand that

Claims (9)

An organic electronic material comprising a charge transporting polymer having a structure branched in three or more directions,
An organic electronic material in which the charge transporting polymer has a trivalent or higher structural unit consisting only of an aromatic carbon hydrogen which may have a substituent.   The charge transporting polymer further includes a divalent structural unit, and the divalent structural unit includes a substituted or unsubstituted aromatic amine structure, carbazole structure, thiophene structure, benzene structure, and fluorene structure. The organic electronic material according to claim 1, which is selected from the group.   The organic electronic material according to claim 2, wherein the charge transporting polymer includes a partial structure in which three or more divalent structural units are bonded to one of the trivalent or higher structural units.   The organic electronic material according to any one of claims 1 to 3, wherein the charge transporting polymer has one or more polymerizable functional groups in a molecule.   An ink composition comprising the organic electronic material according to claim 1 and a solvent.   An organic electronic device comprising a substrate and an organic layer formed using the ink composition according to claim 5.   The organic electronics element according to claim 6, wherein the substrate is a resin film.   The organic electroluminescent element which has an organic layer formed using the ink composition of Claim 5. The organic electroluminescent element according to claim 8, wherein the organic layer is a hole transport layer.

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