JP7009544B2 - Method for manufacturing composition for light emitting element and method for manufacturing light emitting element - Google Patents

Description

The present invention relates to a composition for a light emitting device and a light emitting device containing the same.

A light emitting element such as an organic electroluminescence element can be suitably used for, for example, a display and lighting. As a material used for a light emitting device, for example, Patent Document 1 proposes a composition containing compound H0 and compound EM1.

International Publication No. 2017/170313

However, the light emitting device manufactured by using the above composition does not always have sufficient external quantum efficiency.
Therefore, an object of the present invention is to provide a composition useful for producing a light emitting device having excellent external quantum efficiency, and a light emitting device formed by using the composition.

As a result of diligent studies to solve the above problems, the present inventors have found that in a light emitting element having an organic layer containing a specific composition, a palladium atom has a great influence on the external quantum efficiency of the light emitting element. We have found that the external quantum efficiency of the light emitting element is excellent by setting the amount of palladium atoms in a specific range, and have completed the present invention. It should be noted that Patent Document 1 does not describe that the amount of palladium atoms contained in the composition affects the external quantum efficiency of the light emitting device.

［式中、
ｎ^１Ｈは、０以上の整数を表す。
Ａｒ^１Ｈは、ベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族炭化水素から、前記縮合環骨格を構成する炭素原子に直接結合する水素原子ｎ^１Ｈ個以上を除いた基を表し、この基は置換基を有していてもよい。該置換基が複数存在する場合、それらは同一でも異なっていてもよく、互いに結合して、それぞれが結合する原子とともに環を形成していてもよい。
Ｒ^１Ｈは、アリール基又は１価の複素環基を表し、これらの基は置換基を有していてもよい。該置換基が複数存在する場合、それらは同一でも異なっていてもよく、互いに結合して、それぞれが結合する原子とともに環を形成していてもよい。Ｒ^１Ｈが複数存在する場合、それらは同一でも異なっていてもよく、互いに結合して、それぞれが結合する原子とともに環を形成していてもよい。］
［３］
前記縮合環骨格が、ベンゼン環のみが３個以上５個以下縮合した縮合環骨格である、［１］又は［２］に記載の発光素子用組成物。
［４］
前記縮合環骨格が、アントラセン骨格、フェナントレン骨格、ベンゾアントラセン骨格、ベンゾフェナントレン骨格又はピレン骨格である、［３］に記載の発光素子用組成物。
［５］
前記水素原子及び炭素原子のみからなる芳香族化合物が式（ＦＢ）で表される化合物である、［１］～［４］のいずれかに記載の発光素子用組成物。

［式中、
ｎ^１Ｂは、０以上の整数を表す。
Ａｒ^１Ｂは、芳香族炭化水素環を有する化合物から、前記芳香族炭化水素環を構成する炭素原子に直接結合する水素原子ｎ^１Ｂ個以上を除いた基を表す。
Ｒ^１Ｂは、水素原子及び炭素原子のみからなる炭化水素基を表し、この基は、水素原子及び炭素原子のみからなる置換基を更に有していてもよい。該置換基が複数存在する場合、それらは同一でも異なっていてもよく、互いに結合して、それぞれが結合する原子とともに環を形成していてもよい。Ｒ^１Ｂが複数存在する場合、それらは同一でも異なっていてもよく、互いに結合して、それぞれが結合する炭素原子とともに環を形成していてもよい。］
［６］
前記芳香族炭化水素環が、２環式～７環式の芳香族炭化水素環である、［５］に記載の発光素子用組成物。
［７］
前記芳香族炭化水素環が、ベンゾフルオレン環、ピレン環、フルオランテン環、ジベンゾフルオレン環、ペリレン環、ベンゾフルオランテン環、スピロビフルオレン環、ベンゾスピロビフルオレン環又はアセナフトフルオランテン環である、［６］に記載の発光素子用組成物。
［８］
前記水素原子及び炭素原子のみからなる炭化水素基が、アルキル基、シクロアルキル基又はアリール基（これらの基は、水素原子及び炭素原子のみからなる置換基を有していてもよい。）である、［５］～［７］のいずれかに記載の発光素子用組成物。
［９］
正孔輸送材料、正孔注入材料、電子輸送材料、電子注入材料、発光材料、酸化防止剤及び溶媒からなる群より選ばれる少なくとも１種を更に含有する、［１］～［８］のいずれかに記載の発光素子用組成物。
［１０］
陽極と、陰極と、前記陽極及び前記陰極の間に設けられた有機層とを有する発光素子であり、
前記有機層が、［１］～［９］のいずれかに記載の発光素子用組成物を含有する層である、発光素子。
［１１］
ホスト材料とゲスト材料とが配合された発光素子用組成物の製造方法であって、
ベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族化合物を含むホスト材料を準備するホスト材料準備工程と、
水素原子及び炭素原子のみからなる芳香族化合物を含むゲスト材料を準備するゲスト材料準備工程と、
前記ホスト材料と前記ゲスト材料とを、前記ホスト材料に含まれるパラジウム原子及び前記ゲスト材料に含まれるパラジウム原子の総量が８６．５質量ｐｐｂ以下となる配合比で混合して、発光素子用組成物を得る製造工程と、
を含む、発光素子用組成物の製造方法。
［１２］
前記ゲスト材料準備工程が、
パラジウム原子が混在した前記水素原子及び炭素原子のみからなる芳香族化合物を準備する準備工程（Ｂ－１）と、
前記工程（Ｂ－１）で準備した前記水素原子及び炭素原子のみからなる芳香族化合物の少なくとも一部を精製して、前記パラジウム原子の少なくとも一部を除去する工程（Ｂ－２）と、
を含む、［１１］に記載の製造方法。
［１３］
前記ホスト材料準備工程が、
パラジウム原子が混在した前記ベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族化合物を準備する工程（Ａ－１）と、
前記工程（Ａ－１）で準備した前記ベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族化合物の少なくとも一部を精製して、前記パラジウム原子の少なくとも一部を除去する工程（Ａ－２）と、
を含む、［１１］又は［１２］に記載の製造方法。
［１４］
ホスト材料とゲスト材料とが配合された発光素子用組成物の製造方法であって、
ベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族化合物を含むホスト材料を準備するホスト材料準備工程と、
前記ホスト材料に対するゲスト材料の配合比を決定する決定工程と、
水素原子及び炭素原子のみからなる芳香族化合物を含み、前記配合比で前記ホスト材料と混合したとき前記ホスト材料及び前記ゲスト材料の総量に対する前記ホスト材料に含まれるパラジウム原子及び前記ゲスト材料に含まれるパラジウム原子の総量が８６．５質量ｐｐｂ以下となる、ゲスト材料を準備するゲスト材料準備工程と、
前記ホスト材料と前記ゲスト材料とを前記配合比で混合して、発光素子用組成物を得る製造工程と、
を含む、発光素子用組成物の製造方法。
［１５］
ホスト材料とゲスト材料とが配合された発光素子用組成物の製造方法であって、
水素原子及び炭素原子のみからなる芳香族化合物を含むゲスト材料を準備するゲスト材料準備工程と、
前記ゲスト材料に対するホスト材料の配合比を決定する決定工程と、
ベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族化合物を含み、前記配合比で前記ゲスト材料と混合したとき前記ホスト材料及び前記ゲスト材料の総量に対する前記ホスト材料に含まれるパラジウム原子及び前記ゲスト材料に含まれるパラジウム原子の総量が８６．５質量ｐｐｂ以下となる、ホスト材料を準備するホスト材料準備工程と、
前記ゲスト材料と前記ホスト材料とを前記配合比で混合して、発光素子用組成物を得る製造工程と、
を含む、発光素子用組成物の製造方法。
［１６］
ホスト材料とゲスト材料とが配合された発光素子用組成物の製造方法であって、
ホスト材料としてベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族化合物を準備するホスト材料準備工程と、
ゲスト材料として水素原子及び炭素原子のみからなる芳香族化合物を準備するゲスト材料準備工程と、
前記ホスト材料と前記ゲスト材料との配合比を決定する決定工程と、
前記配合比で前記ホスト材料と前記ゲスト材料とを混合したとき、前記ホスト材料及び前記ゲスト材料の総量に対する前記ホスト材料に含まれるパラジウム原子及び前記ゲスト材料に含まれるパラジウム原子の総量が８６．５質量ｐｐｂ以下となるように、前記ベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族化合物及び前記水素原子及び炭素原子のみからなる芳香族化合物の少なくとも一部を精製する精製工程と、
前記ベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族化合物を含む前記ホスト材料と前記水素原子及び炭素原子のみからなる芳香族化合物を含む前記ゲスト材料とを前記配合比で混合して、発光素子用組成物を得る製造工程と、
を含む、発光素子用組成物の製造方法。
［１７］
前記ベンゼン環のみが３個以上縮合した縮合環骨格を有する芳香族化合物に含まれるパラジウム原子の含有量を測定するホスト材料測定工程と、
前記水素原子及び炭素原子のみからなる芳香族化合物に含まれるパラジウム原子の含有量を測定するゲスト材料測定工程と、
を更に含む、［１１］～［１６］のいずれかに記載の製造方法。
［１８］
陽極と、陰極と、前記陽極及び前記陰極の間に設けられた有機層とを含む、発光素子の製造方法であって、
［１１］～［１７］のいずれかに記載の製造方法により製造された発光素子用組成物により、前記有機層を形成させる工程を含む、発光素子の製造方法。 That is, the present invention provides the following [1] to [18].
[1]
A composition for a light emitting device in which a host material and a guest material are blended.
The host material contains an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed.
The guest material contains an aromatic compound consisting only of hydrogen and carbon atoms.
A composition for a light emitting device, wherein the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material is 86.5 mass ppb or less with respect to the total amount of the host material and the guest material.
[2]
The composition for a light emitting element according to [1], wherein the aromatic compound having a condensed ring skeleton in which only three or more benzene rings are condensed is a compound represented by the formula (FH).

[During the ceremony,
n ^1H represents an integer of 0 or more.
Ar ^1H represents a group obtained by removing n ^1H or more hydrogen atoms directly bonded to carbon atoms constituting the fused ring skeleton from an aromatic hydrocarbon having a fused ring skeleton in which only three or more benzene rings are condensed. This group may have a substituent. When a plurality of the substituents are present, they may be the same or different, or they may be bonded to each other to form a ring with the atom to which each is bonded.
R ^1H represents an aryl group or a monovalent heterocyclic group, and these groups may have a substituent. When a plurality of the substituents are present, they may be the same or different, or they may be bonded to each other to form a ring with the atom to which each is bonded. When a plurality of ^R1Hs are present, they may be the same or different, or they may be bonded to each other to form a ring with the atoms to which each is bonded. ]
[3]
The composition for a light emitting element according to [1] or [2], wherein the condensed ring skeleton is a condensed ring skeleton in which only 3 or more and 5 or less benzene rings are condensed.
[4]
The composition for a light emitting element according to [3], wherein the fused ring skeleton is an anthracene skeleton, a phenanthrene skeleton, a benzoanthracene skeleton, a benzophenanthrene skeleton or a pyrene skeleton.
[5]
The composition for a light emitting element according to any one of [1] to [4], wherein the aromatic compound consisting only of a hydrogen atom and a carbon atom is a compound represented by the formula (FB).

[During the ceremony,
n ^1B represents an integer of 0 or more.
Ar ^1B represents a group obtained by removing ^1B or more of hydrogen atoms directly bonded to carbon atoms constituting the aromatic hydrocarbon ring from the compound having an aromatic hydrocarbon ring.
R ^1B represents a hydrocarbon group consisting only of a hydrogen atom and a carbon atom, and this group may further have a substituent consisting only of a hydrogen atom and a carbon atom. When a plurality of the substituents are present, they may be the same or different, or they may be bonded to each other to form a ring with the atom to which each is bonded. When a plurality of ^R1Bs are present, they may be the same or different, or they may be bonded to each other to form a ring with the carbon atoms to which they are bonded. ]
[6]
The composition for a light emitting element according to [5], wherein the aromatic hydrocarbon ring is a bicyclic to 7 ring type aromatic hydrocarbon ring.
[7]
The aromatic hydrocarbon ring is a benzofluorene ring, a pyrene ring, a fluoranthene ring, a dibenzofluorene ring, a perylene ring, a benzofluoranthene ring, a spirobifluorene ring, a benzospirobifluorene ring or an acenaftfluoranthene ring. , [6]. The composition for a light emitting element.
[8]
The hydrocarbon group consisting only of a hydrogen atom and a carbon atom is an alkyl group, a cycloalkyl group or an aryl group (these groups may have a substituent consisting only of a hydrogen atom and a carbon atom). , The composition for a light emitting element according to any one of [5] to [7].
[9]
Any of [1] to [8] further containing at least one selected from the group consisting of a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material, an antioxidant and a solvent. The composition for a light emitting element according to.
[10]
A light emitting device having an anode, a cathode, and an organic layer provided between the anode and the cathode.
A light emitting device in which the organic layer is a layer containing the composition for a light emitting device according to any one of [1] to [9].
[11]
A method for producing a composition for a light emitting device, which is a mixture of a host material and a guest material.
A host material preparation step for preparing a host material containing an aromatic compound having a condensed ring skeleton in which only three or more benzene rings are condensed.
A guest material preparation process for preparing a guest material containing an aromatic compound consisting only of hydrogen atoms and carbon atoms,
The host material and the guest material are mixed at a blending ratio such that the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material is 86.5 mass ppb or less to form a composition for a light emitting element. And the manufacturing process to get
A method for producing a composition for a light emitting device, which comprises.
[12]
The guest material preparation process
The preparatory step (B-1) for preparing an aromatic compound consisting only of the hydrogen atom and the carbon atom in which the palladium atom is mixed, and
The step (B-2) of purifying at least a part of the aromatic compound consisting only of the hydrogen atom and the carbon atom prepared in the step (B-1) and removing at least a part of the palladium atom.
The production method according to [11].
[13]
The host material preparation process
A step (A-1) of preparing an aromatic compound having a condensed ring skeleton in which only three or more of the benzene rings mixed with palladium atoms are condensed.
A step (A) of purifying at least a part of an aromatic compound having a condensed ring skeleton in which only three or more of the benzene rings prepared in the step (A-1) are condensed to remove at least a part of the palladium atom. -2) and
The production method according to [11] or [12], which comprises.
[14]
A method for producing a composition for a light emitting device, which is a mixture of a host material and a guest material.
A host material preparation step for preparing a host material containing an aromatic compound having a condensed ring skeleton in which only three or more benzene rings are condensed.
A determination step for determining the mixing ratio of the guest material to the host material, and
It contains an aromatic compound consisting only of hydrogen atoms and carbon atoms, and is contained in the palladium atom and the guest material contained in the host material with respect to the total amount of the host material and the guest material when mixed with the host material in the compounding ratio. A guest material preparation step for preparing a guest material and a guest material preparation step in which the total amount of palladium atoms is 86.5 mass ppb or less.
A manufacturing step of mixing the host material and the guest material at the compounding ratio to obtain a composition for a light emitting device, and
A method for producing a composition for a light emitting device, which comprises.
[15]
A method for producing a composition for a light emitting device, which is a mixture of a host material and a guest material.
A guest material preparation process for preparing a guest material containing an aromatic compound consisting only of hydrogen atoms and carbon atoms,
A determination step for determining the mixing ratio of the host material to the guest material, and
Only the benzene ring contains an aromatic compound having a fused ring skeleton in which three or more are condensed, and when mixed with the guest material at the compounding ratio, the host material and the palladium atom contained in the host material with respect to the total amount of the guest material and A host material preparation step for preparing a host material and a host material preparation step in which the total amount of palladium atoms contained in the guest material is 86.5 mass ppb or less.
A manufacturing process for obtaining a composition for a light emitting device by mixing the guest material and the host material at the compounding ratio.
A method for producing a composition for a light emitting device, which comprises.
[16]
A method for producing a composition for a light emitting device, which is a mixture of a host material and a guest material.
A host material preparation step for preparing an aromatic compound having a condensed ring skeleton in which only three or more benzene rings are condensed as a host material, and a host material preparation step.
A guest material preparation process for preparing an aromatic compound consisting only of hydrogen atoms and carbon atoms as a guest material,
A determination step for determining the blending ratio of the host material and the guest material, and
When the host material and the guest material are mixed at the blending ratio, the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material relative to the total amount of the host material and the guest material is 86.5. A purification step of purifying at least a part of an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed and an aromatic compound consisting of only hydrogen atoms and carbon atoms so as to have a mass of ppb or less.
The host material containing an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed and the guest material containing an aromatic compound consisting of only hydrogen atoms and carbon atoms are mixed at the above compounding ratio. , The manufacturing process to obtain the composition for the light emitting element,
A method for producing a composition for a light emitting device, which comprises.
[17]
A host material measuring step for measuring the content of palladium atoms contained in an aromatic compound having a condensed ring skeleton in which only three or more benzene rings are condensed, and a step of measuring the host material.
A guest material measuring step for measuring the content of palladium atoms contained in the aromatic compound consisting only of hydrogen atoms and carbon atoms, and a guest material measuring step.
The production method according to any one of [11] to [16], further comprising.
[18]
A method for manufacturing a light emitting device, comprising an anode, a cathode, and an organic layer provided between the anode and the cathode.
A method for manufacturing a light emitting device, which comprises a step of forming the organic layer with the composition for a light emitting device manufactured by the manufacturing method according to any one of [11] to [17].

According to the present invention, it is possible to provide a composition useful for producing a light emitting device having excellent external quantum efficiency. Further, according to the present invention, it is possible to provide a light emitting device containing the above composition. Further, according to the present invention, it is possible to provide the composition and the method for producing the light emitting element.

Hereinafter, preferred embodiments of the present embodiment will be described in detail.

<Explanation of common terms>
Unless otherwise specified, the terms commonly used in the present specification have the following meanings.

"Room temperature" means 25 ° C.
Me represents a methyl group, Et represents an ethyl group, Bu represents a butyl group, i-Pr represents an isopropyl group, and t-Bu represents a tert-butyl group.
The hydrogen atom may be a deuterium atom or a light hydrogen atom.

The “polymer compound” means a polymer having a molecular weight distribution and having a polystyrene-equivalent number average molecular weight of 1 × 10 ³ to 1 × 10 ⁸ .
The “small molecule compound” means a compound having no molecular weight distribution and having a molecular weight of 1 × ¹⁰⁴ or less.
The “constituent unit” means a unit existing in one or more in a polymer compound.

The "alkyl group" may be linear or branched. The number of carbon atoms of the linear alkyl group is usually 1 to 50, preferably 1 to 20, and more preferably 1 to 10, not including the number of carbon atoms of the substituent. The number of carbon atoms of the branched alkyl group is usually 3 to 50, preferably 3 to 20, and more preferably 4 to 10, not including the number of carbon atoms of the substituent. The alkyl group may have a substituent, for example, a methyl group, an ethyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, 2-. Ethylhexyl group, decyl group, 3,7-dimethyloctyl group, 2-ethyloctyl group, dodecyl group, trifluoromethyl group, 3-phenylpropyl group, 3- (4-methylphenyl) propyl group, 3- (3) Examples thereof include a 5-di-hexylphenyl) propyl group and a 6-ethyloxyhexyl group.
The number of carbon atoms of the "cycloalkyl group" is usually 3 to 50, preferably 4 to 10, not including the number of carbon atoms of the substituent. The cycloalkyl group may have a substituent, and examples thereof include a cyclohexyl group and a methylcyclohexyl group.
The number of carbon atoms of the "alkylene group" is usually 1 or more and 20 or less, preferably 1 or more and 15 or less, and more preferably 1 or more and 10 or less, not including the number of carbon atoms of the substituent. The alkylene group may have a substituent, and examples thereof include a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group and an octylene group.
The number of carbon atoms of the "cycloalkylene group" is usually 3 or more and 20 or less, not including the number of carbon atoms of the substituent. The cycloalkylene group may have a substituent, and examples thereof include a cyclohexylene group.

The "aromatic hydrocarbon group" means a group obtained by removing one or more hydrogen atoms directly bonded to a carbon atom constituting a ring from an aromatic hydrocarbon. A group obtained by removing one hydrogen atom directly bonded to a carbon atom constituting a ring from an aromatic hydrocarbon is also referred to as an "aryl group". A group obtained by removing two hydrogen atoms directly bonded to a carbon atom constituting a ring from an aromatic hydrocarbon is also referred to as an "arylene group".
The number of carbon atoms of the aromatic hydrocarbon group is usually 6 to 60, preferably 6 to 30, and more preferably 6 to 18, not including the number of carbon atoms of the substituent.
The "aromatic hydrocarbon group" is, for example, a monocyclic aromatic hydrocarbon (for example, benzene) or a polycyclic aromatic hydrocarbon (for example, bicyclic such as naphthalene and inden). Aromatic hydrocarbons of , Dibenzophenantrene, dibenzofluorene, perylene and benzofluorenten and other 5-cyclic aromatic hydrocarbons; 6-ring aromatic hydrocarbons such as spirobifluorene; Examples thereof include 7-ring aromatic hydrocarbons such as), except for one or more hydrogen atoms directly bonded to the carbon atoms constituting the ring, and these groups have substituents. May be. Aromatic hydrocarbon groups include groups in which a plurality of these groups are bonded.

The "alkoxy group" may be either linear or branched. The number of carbon atoms of the linear alkoxy group is usually 1 to 40, preferably 1 to 10, not including the number of carbon atoms of the substituent. The number of carbon atoms of the branched alkoxy group is usually 3 to 40, preferably 4 to 10, not including the number of carbon atoms of the substituent. The alkoxy group may have a substituent, for example, a methoxy group, an ethoxy group, an isopropyloxy group, a butyloxy group, a hexyloxy group, a 2-ethylhexyloxy group, a 3,7-dimethyloctyloxy group, and a lauryl. Oxy group is mentioned.
The number of carbon atoms of the "cycloalkoxy group" is usually 3 to 40, preferably 4 to 10, not including the number of carbon atoms of the substituent. The cycloalkoxy group may have a substituent, and examples thereof include a cyclohexyloxy group.
The number of carbon atoms of the "aryloxy group" is usually 6 to 60, preferably 6 to 48, not including the number of carbon atoms of the substituent. The aryloxy group may have a substituent, and examples thereof include a phenoxy group, a naphthyloxy group, an anthrasenyloxy group, and a pyrenyloxy group.

The "heterocyclic group" means a group obtained by removing one or more hydrogen atoms directly bonded to a carbon atom or a hetero atom constituting a ring from a heterocyclic compound. Among the heterocyclic groups, an "aromatic heterocyclic group" is preferable, which is a group obtained by removing one or more hydrogen atoms directly bonded to a carbon atom or a hetero atom forming a ring from an aromatic heterocyclic compound. A group excluding p hydrogen atoms (p represents an integer of 1 or more) directly bonded to a carbon atom or a hetero atom constituting a ring from a heterocyclic compound is also referred to as a “p-valent heterocyclic group”. A group obtained by removing p hydrogen atoms directly bonded to a carbon atom or a hetero atom constituting a ring from an aromatic heterocyclic compound is also referred to as a "p-valent aromatic heterocyclic group".
Examples of the "aromatic heterocyclic compound" include compounds in which the heterocycle itself exhibits aromaticity, such as azole, thiophene, furan, pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene and carbazole, and phenoxazine. , Phenothiazine, benzopyrane and the like, even if the heterocycle itself does not exhibit aromaticity, a compound in which the aromatic ring is condensed in the heterocycle can be mentioned.
The number of carbon atoms of the heterocyclic group is usually 1 to 60, preferably 2 to 40, and more preferably 3 to 20 without including the number of carbon atoms of the substituent. The heteroatom number of the heterocyclic group is usually 1 to 30, preferably 1 to 10, and more preferably 1 to 3 without including the number of carbon atoms of the substituent.
The heterocyclic group may have a substituent, for example, monocyclic heterocyclic compounds (eg, furan, thiophene, oxadiazol, pyrrole, diazole, triazole, tetrazole, pyridine, diazabenzene and triazine. ), Or a polycyclic heterocyclic compound (eg, a bicyclic heterocyclic compound such as azanaphthalene, diazanaphthalene, benzofuran, benzothiophene, indol, benzodiazole and benzothiasiazol; dibenzofuran. , Dibenzothiophene, dibenzoborol, dibenzosilol, dibenzophosphol, dibenzoselenophen, carbazole, azacarbazole, diazacarbazole, phenoxazine, phenothiazine, 9,10-dihydroaclydin, 5,10-dihydrophenazine, phenazaborin, pheno Three-cyclic heterocyclic compounds such as phosphazine, phenoselenazine, phenazacillin, azaanthracene, diazaanthracen, azaphenanthrene and diazaphenanthrene; hexaazatriphenylene, benzocarbazole, benzonaphtholfuran and benzonaphthophen 4 Cyclic heterocyclic compounds; 5-cyclic heterocyclic compounds such as dibenzocarbazole, indolocarbazole and indenocarbazole; 6-cyclic heterocyclic compounds such as carbazolocarbazole, benzoindrocarbazole and benzoindenocarbazole. Compounds; and 7-cyclic heterocyclic compounds such as dibenzoindrocarbazole can be mentioned), to which groups excluding one or more hydrogen atoms directly bonded to the atoms constituting the ring can be mentioned. May have a substituent. The heterocyclic group includes a group in which a plurality of these groups are bonded.

The "halogen atom" refers to a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.

The "amino group" may have a substituent, and a substituted amino group (that is, a secondary amino group or a tertiary amino group, preferably a tertiary amino group) is preferable. As the substituent contained in the amino group, an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group is preferable. When a plurality of substituents having an amino group are present, they may be the same and different, or they may be bonded to each other to form a ring together with the nitrogen atom to which each is bonded.
Examples of the substituted amino group include a dialkylamino group, a dicycloalkylamino group and a diarylamino group.
Examples of the amino group include a dimethylamino group, a diethylamino group, a diphenylamino group, a bis (methylphenyl) amino group, and a bis (3,5-di-tert-butylphenyl) amino group.

The "alkenyl group" may be either linear or branched. The number of carbon atoms of the linear alkenyl group is usually 2 to 30, preferably 3 to 20, not including the number of carbon atoms of the substituent. The number of carbon atoms of the branched alkenyl group does not include the number of carbon atoms of the substituent and is usually 3 to 30, preferably 4 to 20.
The number of carbon atoms of the "cycloalkenyl group" is usually 3 to 30, preferably 4 to 20, not including the number of carbon atoms of the substituent.
The alkenyl group and the cycloalkenyl group may have a substituent, for example, a vinyl group, a propenyl group, a butenyl group, a 3-butenyl group, a 3-pentenyl group, a 4-pentenyl group, a 1-hexenyl group, 5 Examples thereof include a hexenyl group, a 7-octenyl group, and a group in which these groups have a substituent.

The "alkynyl group" may be either linear or branched. The number of carbon atoms of the alkynyl group is usually 2 to 20, preferably 3 to 20, without including the carbon atom of the substituent. The number of carbon atoms of the branched alkynyl group is usually 4 to 30, preferably 4 to 20, without including the carbon atom of the substituent.
The number of carbon atoms of the "cycloalkynyl group" is usually 4 to 30, preferably 4 to 20, without including the carbon atom of the substituent.
The alkynyl group and the cycloalkynyl group may have a substituent, for example, an ethynyl group, a propynyl group, a butynyl group, a pentynyl group, a hexynyl group, a 5-hexynyl group, and these groups have a substituent. The group is mentioned.

The "crosslinking group" is a group capable of forming a new bond by being subjected to heating, ultraviolet irradiation, near-ultraviolet irradiation, visible light irradiation, infrared irradiation, radical reaction, etc., and is preferably a group of the formula (B). -1) It is a group represented by any of the formulas (B-17). These groups may have substituents.

Examples of the "substituted group" include a halogen atom, a cyano group, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an amino group and a substituted amino group. Examples thereof include an alkenyl group, a cycloalkenyl group, an alkynyl group and a cycloalkynyl group. The substituent may be a cross-linking group. When a plurality of substituents are present, they may be bonded to each other to form a ring together with the atoms to which they are bonded, but it is preferable not to form a ring.

The "amount of palladium atoms" can be measured by the ICP / MS method (inductively coupled plasma mass spectrometry). That is, the "amount of palladium atom" means the mass concentration of the palladium atom as measured by the ICP / MS method. Further, when the "amount of palladium atom" is "0 mass ppb", it means that the mass concentration of the palladium atom is not more than the detection limit when measured by the ICP / MS method.

In the composition for a light emitting device of the present embodiment, the host material means a material that physically, chemically or electrically interacts with the guest material. By this interaction, for example, it becomes possible to improve or adjust the light emitting property, the charge transport property, or the charge injection property of the composition for a light emitting device of the present embodiment.
In the composition for a light emitting device of the present embodiment, the light emitting material will be described as an example. By electrically interacting with the host material and the guest material and efficiently transferring electrical energy from the host material to the guest material. The guest material can be made to emit light more efficiently.

<Host material>
The host material contains an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed. An aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed may contain only one type of fused ring skeleton in which only three or more benzene rings are condensed, and may contain two or more types. You may. Further, the aromatic compound having a condensed ring skeleton in which only three or more benzene rings are condensed may contain only one condensed ring skeleton in which only three or more benzene rings are condensed in the compound. It may be included. Hereinafter, an aromatic compound having a condensed ring skeleton in which only three or more benzene rings contained in the host material are condensed may be referred to as an "aromatic compound for a host material".

In the condensed ring skeleton of the aromatic compound for the host material, the number of condensed benzene rings is usually 3 to 10, and the external quantum efficiency of the light emitting element of the present embodiment is more excellent, which is preferable. The number is 3 to 7, more preferably 3 to 5, and even more preferably 3 or 4.
The condensed ring skeleton of the aromatic compound for the host material can also be said to be the carbon skeleton of the condensed ring in which only three or more benzene rings are condensed. The fused ring skeleton is preferably an anthracene skeleton, phenanthracene skeleton, benzoanthracene skeleton, benzophenanthrene skeleton or pyrene skeleton, and more preferably anthracene skeleton or benzoanthracene skeleton, because the external quantum efficiency of the light emitting element of the present embodiment is more excellent. Alternatively, it is a pyrene skeleton, more preferably an anthracene skeleton.

The aromatic compound for the host material may be an aromatic hydrocarbon having a fused ring skeleton in which only three or more benzene rings are condensed (hereinafter, also referred to as “condensed ring-containing aromatic hydrocarbon”), and the aromatic. The hydrocarbon may have a substituent. The substituent that the fused ring-containing aromatic hydrocarbon may have is preferably a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, a monovalent heterocyclic group or a substituted amino. It is a group, more preferably an alkyl group, a cycloalkyl group, an aryl group or a monovalent heterocyclic group, still more preferably an aryl group or a monovalent heterocyclic group, and particularly preferably an aryl group. The group of may further have a substituent.
Among the substituents that the fused ring-containing aromatic hydrocarbon may have, the aryl group is preferably from a monocyclic or bicyclic to 6-ring aromatic hydrocarbon directly to the carbon atom constituting the ring. A group excluding one or more hydrogen atoms to be bonded, more preferably one or more hydrogen atoms directly bonded to the carbon atoms constituting the ring from monocyclic or bicyclic to tetracyclic aromatic hydrocarbons. It is a group excluding benzene, more preferably a group obtained by removing one or more hydrogen atoms directly bonded to a carbon atom constituting a ring from benzene, naphthalene, dihydrophenanthrene, fluorene or benzofluorene, and particularly preferably a phenyl group. Alternatively, it is a naphthyl group, and these groups may have a substituent.
Among the substituents that the fused ring-containing aromatic hydrocarbon may have, the monovalent heterocyclic group preferably constitutes a ring from a monocyclic or bicyclic to 6-cyclic heterocyclic compound. A group excluding one or more hydrogen atoms directly bonded to an atom, more preferably a monocyclic or bicyclic to tetracyclic heterocyclic compound, hydrogen atom 1 directly bonded to a ring-constituting atom. It is a group excluding one or more, and is directly bonded to an atom constituting a ring from pyridine, diazabenzene, triazine, azanaphthalene, diazanaphthalene, dibenzofuran, dibenzothiophene, carbazole, benzocarbazole, benzonaphthofuran or benzonaphthophene. It is a group excluding one or more hydrogen atoms, and these groups may have a substituent.
Among the substituted amino groups in the substituents that the fused ring-containing aromatic hydrocarbon may have, the substituent of the amino group is preferably an aryl group or a monovalent heterocyclic group, more preferably an aryl group. The group of may further have a substituent. The example and preferred range of the aryl group as the substituent of the amino group is the same as the example and preferred range of the aryl group in the substituent which the fused ring-containing aromatic hydrocarbon may have. Examples and preferred ranges of monovalent heterocyclic groups which are substituents of amino groups include examples of monovalent heterocyclic groups and preferred ranges of substituents which may be possessed by fused ring-containing aromatic hydrocarbons. It is the same.

The fused ring-containing aromatic hydrocarbon preferably has a substituent because the external quantum efficiency of the light emitting element of the present embodiment is more excellent. When the fused ring-containing aromatic hydrocarbon has a substituent, the total number of substituents of the fused ring-containing aromatic hydrocarbon is usually 1 to 20 (provided that the fused ring-containing aromatic hydrocarbon has a substituent). The total number of hydrogen atoms is less than or equal to the total number of hydrogen atoms, and the same applies hereinafter.) The number is preferably 1 to 15, and more preferably 1 to 10 because the host material can be easily synthesized. It is more preferably 1 to 7, particularly preferably 1 to 5, and particularly preferably 1 to 3.

As the substituent which the substituent which the fused ring-containing aromatic hydrocarbon may have may further have, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group and an aryl group are preferable. It is a monovalent heterocyclic group or a substituted amino group, more preferably an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, and further preferably an alkyl group or a cycloalkyl group. Yes, these groups may further have a substituent, but it is preferable that they do not further have a substituent.
Examples and preferred ranges of the aryl group, the monovalent heterocyclic group and the substituted amino group in the substituent which the substituent which the fused ring-containing aromatic hydrocarbon may have may further have are condensed, respectively. It is the same as the example and preferable range of the aryl group, the monovalent heterocyclic group and the substituted amino group in the substituent which the ring-containing aromatic hydrocarbon may have.

The host material may further contain a compound other than the aromatic compound for the host material, but it is preferable that the aromatic compound for the host material is the main component. The content ratio of the aromatic compound for the host material in the host material may be, for example, 10% by mass or more, and since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, 30% by mass or more is preferable, and 50% by mass is preferable. % Or more is more preferable, 70% by mass or more is further preferable, 90% by mass or more is particularly preferable, 95% by mass or more is particularly preferable, and 100% by mass may be used.
The host material may contain only one type of aromatic compound for the host material, or may contain two or more types. When the host material further contains a compound other than the aromatic compound for the host material, the host material may contain only one compound other than the aromatic compound for the host material, and may contain two or more kinds. May be good.

The aromatic compound for the host material may be a polymer compound (hereinafter, also referred to as “polymer host material”) or a low molecular weight compound (hereinafter, also referred to as “low molecular weight host material”). Low molecular weight host materials are preferred.

(Small molecule host material)
The molecular weight of the small molecule host material is usually 1 × 10 ² to 1 × 10 ⁴ , preferably 2 × 10 ² to 5 × 10 ³ , and more preferably 3 × 10 ² to 2 × 10 ³ . , More preferably 4 × 10 ² to 1 × 10 ³ .
The total number of condensed ring skeletons in which only three or more benzene rings contained in the low molecular weight host material are condensed is usually 1 to 10, and the external quantum efficiency of the light emitting element of the present embodiment is more excellent. The number is preferably 1 to 7, more preferably 1 to 5, still more preferably 1 to 3, and particularly preferably 1.
The small molecule host material may contain only one type of fused ring skeleton in which only three or more benzene rings are condensed, or may contain two or more types, but since the synthesis of the small molecule host material is easy, the small molecule host material may be contained. It is preferably 1 to 5 types, more preferably 1 to 3 types, and further preferably 1 type.
Since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, the low molecular weight host material has a fragrance having a condensed ring skeleton in which only three or more benzene rings are condensed and a condensed ring skeleton in which only three or more benzene rings are condensed. It is preferable to include it as a group (hereinafter, also referred to as "condensation ring-containing aromatic hydrocarbon group") from which one or more hydrogen atoms directly bonded to carbon atoms constituting the condensed ring skeleton are removed from the group hydrocarbon. The group may have a substituent.
The total number of fused ring-containing aromatic hydrocarbon groups contained in the small molecule host material is usually 1 to 10, and the external quantum efficiency of the light emitting element of the present embodiment is more excellent, so that it is preferably 1. The number is 7 to 7, more preferably 1 to 5, still more preferably 1 to 3, and particularly preferably 1.
The small molecule host material may contain only one type of fused ring-containing aromatic hydrocarbon group, or may contain two or more types, but it is preferable to use one type because it is easy to synthesize the small molecule host material. It is ~ 5 kinds, more preferably 1 ~ 3 kinds, and further preferably 1 kind.
In the low molecular weight host material, examples and preferable ranges of the substituents that the fused ring-containing aromatic hydrocarbon group may have are examples of the substituents that the condensed ring-containing aromatic hydrocarbon may have and preferable. Same as range.

[Compound represented by formula (FH)]
The small molecule host material is preferably a compound represented by the formula (FH) because the external quantum efficiency of the light emitting element of the present embodiment is more excellent.

n ^1H is usually an integer of 10 or less, and is preferably an integer of 7 or less, more preferably an integer of 5 or less, and further preferably an integer of 5 or less because the compound represented by the formula (FH) can be easily synthesized. It is preferably an integer of 3 or less. Further, n ^1H is preferably an integer of 1 or more because the external quantum efficiency of the light emitting device of the present embodiment is more excellent.

In Ar ^1H , the substituent which the fused ring-containing aromatic hydrocarbon group may have is a substituent other than the aryl group and the monovalent heterocyclic group, preferably a halogen atom, an alkyl group and a cycloalkyl group. , An alkoxy group, a cycloalkoxy group or a substituted amino group, more preferably an alkyl group or a cycloalkyl group, and these groups may further have a substituent.
Examples of substituted amino groups in the substituents that the fused ring-containing aromatic hydrocarbon may have and preferred ranges are examples of substituted amino groups in the substituents that the fused ring-containing aromatic hydrocarbon may have. And the same as the preferred range.
Examples and preferred ranges of substituents that the fused ring-containing aromatic hydrocarbon may have may further include substituents that the fused ring-containing aromatic hydrocarbon may have. Is the same as the examples and preferred ranges of substituents that may have further.

R ^1H is preferably an aryl group which may have a substituent because the external quantum efficiency of the light emitting device of the present embodiment is more excellent.
Examples and preferred ranges of aryl groups and monovalent heterocyclic groups in ^R1H are examples of aryl groups and monovalent heterocyclic groups in substituents that the fused ring-containing aromatic hydrocarbons may have, respectively. Same as the preferred range.
Examples of substituents that ^R1H may have and preferred ranges include examples of substituents that may be further possessed by the condensed ring-containing aromatic hydrocarbons and preferred ranges. It is the same.

Examples of the small molecule host material include compounds represented by the following formulas and compounds described in Examples. These compounds may have substituents. In the formula, Z ¹ represents an oxygen atom or a sulfur atom. When a plurality of Z ^1s exist, they may be the same or different.

(Polymer host material)
The polystyrene-equivalent number average molecular weight of the polymer host material is preferably 5 × 10 ³ to 1 × 10 ⁶ , more preferably 1 × 10 ⁴ to 5 × 10 ⁵ , and even more preferably 2 × 10 ⁴ to. It is 2 × 10 ⁵ . The polystyrene-equivalent weight average molecular weight of the polymer host material is preferably 1 × 10 ⁴ to 2 × 10 ⁶ , more preferably 2 × 10 ⁴ to 1 × 10 ⁶ , and even more preferably 5 × 10 ⁴ to. It is 5 × 10 ⁵ .
The polymer host material may be any of a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, and other embodiments, but a plurality of kinds of raw material monomers may be used. It is preferably a copolymerized copolymer.
The polymer host material preferably contains a condensed ring skeleton in which only three or more benzene rings are condensed, as an aromatic hydrocarbon group having a condensed ring skeleton in which only three or more benzene rings are condensed, and this group is a substituent. May have.
Since the polymer host material is more excellent in external quantum efficiency of the light emitting element of the present embodiment, it is preferable to contain a fused ring-containing aromatic hydrocarbon group in the main chain of the polymer compound, and the fused ring-containing aromatic hydrocarbon is preferably contained. It is more preferable to contain a group (a divalent fused ring-containing aromatic hydrocarbon group) obtained by removing two hydrogen atoms directly bonded to carbon atoms constituting the ring from hydrogen. These groups may have substituents.
In the polymer host material, the fused ring-containing aromatic hydrocarbon group has one or more hydrogen atoms (preferably 5) from the compound represented by the formula (FH) because the external quantum efficiency of the light emitting element of the present embodiment is more excellent. The number is preferably 1 or less, more preferably 1 to 3, and even more preferably 2).
In the polymer host material, the content of the fused ring-containing aromatic hydrocarbon group contained in the polymer compound is usually 0.1 mol with respect to the total content of all the constituent units contained in the polymer compound. % To 100 mol%, and the external quantum efficiency of the light emitting element of the present embodiment is more excellent. Therefore, it is preferably 1 mol% to 100 mol%, more preferably 10 mol% to 100 mol%, and further preferably. Is 30 mol% to 100 mol%.
The polymer host material may contain only one type of fused ring-containing aromatic hydrocarbon group, or may contain two or more types, but it is preferable to use one type because the polymer host material can be easily synthesized. It is ~ 5 kinds, more preferably 1 ~ 3 kinds, and further preferably 1 kind.
In the polymer host material, examples and preferred ranges of substituents that the fused ring-containing aromatic hydrocarbon group may have are examples of substituents that the condensed ring-containing aromatic hydrocarbon may have and preferred. Same as range.

The polymer host material may contain a structural unit other than the fused ring-containing aromatic hydrocarbon group, and the main chain of the polymer compound may contain a structural unit other than the condensed ring-containing aromatic hydrocarbon group. preferable.
Examples of the structural unit other than the fused ring-containing aromatic hydrocarbon group include an aromatic hydrocarbon group (preferably an arylene group) other than the fused ring-containing aromatic hydrocarbon group and a heterocyclic group (preferably a divalent heterocycle). Groups) and groups in which one or more hydrogen atoms are removed from aromatic amines (preferably groups in which two hydrogen atoms are removed) may be mentioned, and these groups may have a substituent. The examples and preferred ranges of the substituents are the same as the examples and preferred ranges of substituents that the fused ring-containing aromatic hydrocarbon may have.
In the polymer host material, hydrogen atom 1 from the fused ring-containing aromatic hydrocarbon group, the aromatic hydrocarbon group other than the fused ring-containing aromatic hydrocarbon group, the heterocyclic group and the aromatic amine contained in the polymer compound. The total content of the groups excluding the group is usually 1 mol% to 100 mol% with respect to the total content of all the constituent units contained in the polymer compound, and is outside the light emitting element of the present embodiment. Since the quantum efficiency is more excellent, it is preferably 50 mol% to 100 mol%, and more preferably 70 mol% to 100 mol%.
The polymer host material may contain only one type of structural unit other than the fused ring-containing aromatic hydrocarbon group in the polymer compound, or may contain two or more types.

<Guest material>
Guest materials include aromatic compounds consisting only of hydrogen and carbon atoms. Hereinafter, an aromatic compound consisting only of hydrogen atoms and carbon atoms contained in a guest material may be referred to as an “aromatic compound for guest materials”.
The guest material is different from the host material.
"Aromatic compound consisting only of hydrogen atom and carbon atom" means a compound in which all the elements constituting the compound are composed only of hydrogen atom and carbon atom and the compound has an aromatic hydrocarbon ring. means.
The aromatic compound consisting only of a hydrogen atom and a carbon atom may contain only one aromatic hydrocarbon ring or two or more aromatic hydrocarbon rings in the compound. Further, the aromatic compound consisting only of a hydrogen atom and a carbon atom may contain only one aromatic hydrocarbon ring or two or more aromatic hydrocarbon rings in the compound.
In an aromatic compound consisting only of a hydrogen atom and a carbon atom, examples of the aromatic hydrocarbon ring contained in the compound include the aromatic hydrocarbon ring exemplified in the above-mentioned section on aromatic hydrocarbon groups. Since the external quantum efficiency of the light emitting element of the embodiment is more excellent, it is a monocyclic or bicyclic to 7 ring aromatic hydrocarbon ring, and these aromatic hydrocarbon rings are composed only of hydrogen atom and carbon atom. May have a hydrocarbon group.
Since the external quantum efficiency of the light emitting element of the present embodiment is more excellent in an aromatic compound consisting only of a hydrogen atom and a carbon atom, at least one of the aromatic hydrocarbon rings contained in the compound is a polycyclic aromatic compound. It is preferably a hydrocarbon ring. This polycyclic aromatic hydrocarbon may have a hydrocarbon group consisting only of a hydrogen atom and a carbon atom. Examples of the polycyclic aromatic hydrocarbon ring include the polycyclic aromatic hydrocarbon ring exemplified in the above-mentioned section of the aromatic hydrocarbon group, and the external quantum efficiency of the light emitting element of the present embodiment is high. Since it is more excellent, it is preferably a 2-ring to 7-ring aromatic hydrocarbon ring, more preferably a 4-ring to 7-ring aromatic hydrocarbon ring, and further preferably a benzofluorene ring or a pyrene ring. , Fluorene ring, dibenzofluorene ring, perylene ring, benzofluorene ring, spirobifluorene ring, benzospirobifluorene ring or acenaftfluorene ring, particularly preferably a fluorene ring, a benzofluorene ring or an acena. It is a hydrocarbon ring. These aromatic hydrocarbon rings may have a hydrocarbon group consisting only of a hydrogen atom and a carbon atom.
The hydrocarbon group consisting only of a hydrogen atom and a carbon atom is not particularly limited as long as it is a group consisting only of a hydrogen atom and a carbon atom. Examples of the hydrocarbon group consisting of only a hydrogen atom and a carbon atom include an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, a cycloalkenyl group, an alkynyl group or a cycloalkynyl group. Since the external quantum efficiency is more excellent, it is preferably an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group or a cycloalkenyl group, more preferably an alkyl group, a cycloalkyl group or an aryl group, and further preferably an aryl group. be. These groups may further have a substituent consisting only of a hydrogen atom and a carbon atom.
The examples and preferred ranges of aryl groups in hydrocarbon groups consisting only of hydrogen and carbon atoms are the same as the examples and preferred ranges of aryl groups in substituents that fused ring-containing aromatic hydrocarbons may have.
In an aromatic compound consisting only of hydrogen atoms and carbon atoms, when the aromatic hydrocarbon ring contained in the compound has a hydrocarbon group consisting only of hydrogen atoms and carbon atoms, the hydrogen atoms and carbon contained in the aromatic hydrocarbons. The total number of hydrocarbon groups consisting only of atoms is usually 1 to 20, and since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, it is preferably 1 to 10 and more preferably. Is 1 to 7, more preferably 1 to 5, and particularly preferably 1 to 3.
The substituent consisting only of a hydrogen atom and a carbon atom is not particularly limited as long as it is a group consisting only of a hydrogen atom and a carbon atom. Examples of the substituent consisting only of a hydrogen atom and a carbon atom include an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, a cycloalkenyl group, an alkynyl group or a cycloalkynyl group, and an alkyl group and a cycloalkyl group are preferable. , Aryl group, alkenyl group or cycloalkenyl group, more preferably an alkyl group, a cycloalkyl group or an aryl group. These groups may further have a substituent consisting only of a hydrogen atom and a carbon atom, but preferably have no further substituent.
The examples and preferred ranges of aryl groups in substituents consisting only of hydrogen and carbon atoms are the same as the examples and preferred ranges of aryl groups in substituents that fused ring-containing aromatic hydrocarbons may have.

The guest material may further contain a compound other than the aromatic compound consisting only of a hydrogen atom and a carbon atom, but it is preferable that the guest material is mainly composed of an aromatic compound consisting only of a hydrogen atom and a carbon atom. The content ratio of the aromatic compound consisting only of hydrogen atoms and carbon atoms in the guest material may be, for example, 10% by mass or more, and the external quantum efficiency of the light emitting element of the present embodiment is more excellent, so that it is 30% by mass or more. Is preferable, 50% by mass or more is more preferable, 70% by mass or more is further preferable, 90% by mass or more is particularly preferable, 95% by mass or more is particularly preferable, and 100% by mass may be used.
The guest material may contain only one kind of aromatic compound consisting of only hydrogen atoms and carbon atoms, or may contain two or more kinds of aromatic compounds. When the guest material further contains a compound other than the aromatic compound consisting only of hydrogen atoms and carbon atoms, the guest material may contain only one compound other than the aromatic compound for guest materials, and two kinds thereof. The above may be contained.

The aromatic compound for a guest material may be a polymer compound (hereinafter, also referred to as “polymer guest material”) or a low molecular weight compound (hereinafter, also referred to as “low molecular weight guest material”). , Low molecular weight guest materials are preferred.

(Small molecule guest material)
The molecular weight of the small molecule guest material is usually 1 × 10 ² to 1 × 10 ⁴ , preferably 2 × 10 ² to 5 × 10 ³ , and more preferably 3 × 10 ² to 2 × 10 ³ . , More preferably 4 × 10 ² to 1 × 10 ³ .
The total number of aromatic hydrocarbon rings contained in the small molecule guest material is usually 1 to 60, and the external quantum efficiency of the light emitting element of the present embodiment is more excellent, so that it is preferably 1 to 30. The number is, more preferably 1 to 15, still more preferably 1 to 10, and particularly preferably 1 to 6.
The small molecule guest material may contain only one type of aromatic hydrocarbon ring, or may contain two or more types, but since it is easy to synthesize a small molecule guest material, one to ten types are preferable. It is more preferably 1 to 8 types, further preferably 2 to 6 types, and particularly preferably 2 to 4 types.
When at least one of the aromatic hydrocarbon rings contained in the low molecular weight guest material is a polycyclic aromatic hydrocarbon ring, the total number of polycyclic aromatic hydrocarbon rings is usually one. The number is ~ 20, and since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, the number is preferably 1 to 10, more preferably 1 to 7, and even more preferably 1 to 5. It is particularly preferable that the number is 1 to 3.
Since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, the low molecular weight guest material preferably contains an aromatic hydrocarbon ring as an aromatic hydrocarbon group, and is a monocyclic or bicyclic to 7-ring type. It is more preferable to include it as a group obtained by removing one or more hydrogen atoms directly bonded to carbon atoms constituting the ring from the aromatic hydrocarbons of the above. These groups may have a hydrocarbon group consisting only of a hydrogen atom and a carbon atom.
The total number of aromatic hydrocarbon groups contained in the small molecule guest material is usually 1 to 60, and the external quantum efficiency of the light emitting element of the present embodiment is more excellent, so that it is preferably 1 to 30. The number is, more preferably 1 to 15, still more preferably 1 to 10, and particularly preferably 1 to 6.
The small molecule guest material may contain only one type of aromatic hydrocarbon group or may contain two or more types, but since it is easy to synthesize a small molecule guest material, one to ten types are preferable. It is more preferably 1 to 8 types, further preferably 2 to 6 types, and particularly preferably 2 to 4 types.
In the low molecular weight guest material, at least one of the aromatic hydrocarbon groups is a group obtained by removing one or more hydrogen atoms directly bonded to the carbon atoms constituting the ring from the polycyclic aromatic hydrocarbon (hereinafter, "" It is also preferably a polycyclic aromatic hydrocarbon group. This group may have a hydrocarbon group consisting only of a hydrogen atom and a carbon atom.
As the polycyclic aromatic hydrocarbon group, for example, one hydrogen atom directly bonded to a carbon atom constituting the ring from the polycyclic aromatic hydrocarbon exemplified in the above-mentioned section of aromatic hydrocarbon group. Groups other than the above are mentioned, and since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, preferably, a 2-ring to 7-ring aromatic hydrocarbon is directly bonded to a carbon atom constituting a ring. A group excluding one or more hydrogen atoms, more preferably a group excluding one or more hydrogen atoms directly bonded to the carbon atoms constituting the ring from a 4-ring to 7-ring aromatic hydrocarbon. More preferably, a hydrogen atom 1 directly bonded to a carbon atom constituting a ring from benzofluorene, pyrene, fluorantene, dibenzofluorene, perylene, benzofluorenten, spirobifluorene, benzospirobifluorene or acenaftfluorenten. It is a group excluding one or more, and particularly preferably, it is a group excluding one or more hydrogen atoms directly bonded to a carbon atom constituting a ring from fluorentene, benzofluorentene or acenaftfluoranthen. These groups may have a hydrocarbon group consisting only of a hydrogen atom and a carbon atom.
When the low molecular weight guest material contains polycyclic aromatic hydrocarbon groups, the total number of polycyclic aromatic hydrocarbon groups contained in the low molecular weight guest material is usually 1 to 20. Since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, the number is preferably 1 to 10, more preferably 1 to 7, still more preferably 1 to 5, and particularly preferably 1. Is 1 to 3 pieces.
In the low molecular weight guest material, when the aromatic hydrocarbon group has a hydrocarbon group consisting only of hydrogen atom and carbon atom, the total number of hydrocarbon groups consisting only of hydrogen atom and carbon atom of the aromatic hydrocarbon group. Is usually 1 to 20, and since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, it is preferably 1 to 10, more preferably 1 to 7, and even more preferably. Is 1 to 5, and particularly preferably 1 to 3.

[Compound represented by formula (FB)]
The small molecule guest material is preferably a compound represented by the formula (FB) because the external quantum efficiency of the light emitting element of the present embodiment is more excellent. However, the compound represented by the formula (FB) is different from the compound represented by the formula (FH).

n ^1B is usually an integer of 20 or less, and is preferably an integer of 10 or less, more preferably an integer of 7 or less, and further preferably an integer of 7 or less because the compound represented by the formula (FB) can be easily synthesized. It is preferably an integer of 5 or less, and particularly preferably an integer of 3 or less. Further, n ^1B is preferably an integer of 1 or more because the external quantum efficiency of the light emitting device of the present embodiment is more excellent.

Examples of Ar ^1B include groups obtained by removing n ^1B or more hydrogen atoms directly bonded to carbon atoms constituting a ring from monocyclic or bicyclic to 7-ring aromatic hydrocarbons.
Ar ^1B is preferably the above-mentioned polycyclic aromatic hydrocarbon group because the external quantum efficiency of the light emitting element of the present embodiment is more excellent, and examples and preferable ranges of this group are the same as described above.

The examples and preferred ranges of the hydrocarbon groups consisting only of hydrogen atoms and carbon atoms in R ^1B are the same as described above.

Examples of the low-molecular-weight guest material include aromatic compounds consisting only of hydrogen atoms and carbon atoms, compounds represented by the following formulas, and compounds described in Examples among the compounds exemplified as the above-mentioned low-molecular-weight host materials. Illustrated. These compounds may have a substituent consisting only of a carbon atom and a hydrogen atom.

(Polymer guest material)
The preferred ranges of the polystyrene-equivalent number average molecular weight and the weight average molecular weight of the polymer guest material are the same as the preferred ranges of the polystyrene-equivalent number average molecular weight and the weight average molecular weight of the polymer host material, respectively.
The polymer guest material may be any of a block copolymer, a random copolymer, an alternating copolymer, a graft copolymer, and other embodiments, but a plurality of kinds of raw material monomers may be used. It is preferably a copolymerized copolymer.
The polymer guest material preferably contains an aromatic hydrocarbon ring as an aromatic hydrocarbon group, which group may have a substituent.
Since the polymer guest material is more excellent in external quantum efficiency of the light emitting element of the present embodiment, it is preferable to contain an aromatic hydrocarbon group in the main chain of the polymer compound, and it is more preferable to contain an arylene group. These groups may have a hydrocarbon group consisting only of a hydrogen atom and a carbon atom.
In the polymer guest material, the aromatic hydrocarbon group has one or more hydrogen atoms (preferably five or less) from the compound represented by the formula (FB) because the external quantum efficiency of the light emitting element of the present embodiment is more excellent. Yes, more preferably 1 to 3, and even more preferably 2).
In the polymer guest material, the content of the aromatic hydrocarbon group is usually 1 mol% to 100 mol% with respect to the total content of all the constituent units contained in the polymer compound, and is in the present embodiment. Since the external quantum efficiency of the light emitting element is more excellent, it is preferably 30 mol% to 100 mol%, more preferably 60 mol% to 100 mol%, and further preferably 90 mol% to 100 mol%.
In the polymer guest material, at least one of the aromatic hydrocarbon groups is preferably a polycyclic aromatic hydrocarbon group, which group has a hydrocarbon group consisting only of a hydrogen atom and a carbon atom. May be.
In the polymer guest material, the content of the polycyclic aromatic hydrocarbon group is usually 1 mol% to 100 mol% with respect to the total content of all the constituent units contained in the polymer compound. Since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, it is preferably 10 mol% to 100 mol%, more preferably 30 mol% to 100 mol%, and further preferably 50 mol% to 100 mol%. Is.
The polymer guest material may contain only one type of aromatic hydrocarbon group or may contain two or more types, but it is preferably one type because the external quantum efficiency of the light emitting element of the present embodiment is more excellent. It is ~ 10 kinds, more preferably 2 ~ 8 kinds, further preferably 2 ~ 6 kinds, and particularly preferably 2 ~ 4 kinds.

The polymer guest material may contain a structural unit consisting only of hydrogen atoms and carbon atoms other than the aromatic hydrocarbon group. In the polymer guest material, when the polymer compound contains a structural unit consisting only of a hydrogen atom other than an aromatic hydrocarbon group and a carbon atom, hydrogen other than the aromatic hydrocarbon group is contained in the main chain of the polymer compound. It preferably contains a building block consisting only of atoms and carbon atoms.
Examples of the structural unit consisting only of a hydrogen atom and a carbon atom other than the aromatic hydrocarbon group include an alkylene group and a cycloalkylene group, and these groups have a hydrocarbon group consisting only of a hydrogen atom and a carbon atom. May be.
In the polymer guest material, the polymer compound may contain only one type of structural unit consisting of only hydrogen atoms and carbon atoms other than the aromatic hydrocarbon group, or may contain two or more types.

<Amount of palladium atom contained in guest material (C ¹ )>
In the composition for a light emitting device of the present embodiment, the amount of palladium atoms (C ¹ ) contained in the guest material is usually 1400 mass ppb or less with respect to the total amount of the guest material. The phrase "amount of palladium atom contained in the guest material" does not mean that the guest material contains a palladium atom, and the guest material may or may not contain a palladium atom. good. In the guest material of the present embodiment, the amount of the palladium atom is preferably 500 mass ppb or less, more preferably 140 mass ppb or less, still more preferably 140 mass ppb or less, because the external quantum efficiency of the light emitting element of the present embodiment is more excellent. Is 50 mass ppb or less, particularly preferably 25 mass ppb or less, particularly preferably 14 mass ppb or less, particularly more preferably 13 mass ppb or less, and even more preferably 10 mass ppb or less. Particularly preferably, it is 7 ppb or less. Further, in the guest material of the present embodiment, the amount of the palladium atom may be 5 mass ppb or less, 2 mass ppb or less, 1 mass ppb or less, or 0.5 mass. It may be ppb or less, 0.1 mass ppb or less, or 0 mass ppb or less.

The amount of palladium atom (C ¹ ) contained in the guest material of the present embodiment is C 1 when the guest material of the present embodiment is one kind, and the amount of the palladium atom of the one kind of guest material is C ¹ . When the guest material in the form is composed of a plurality of kinds of compounds having different amounts of palladium atoms, C ¹ is calculated according to the amount of the palladium atoms of the plurality of kinds of compounds and the mass ratio of each compound. ^A specific calculation method of C1 will be described with reference to Examples D1 and D2 described later.

First, in Example D1, since the amount of the palladium atom of the compound EM2 measured by the ICP / MS method is below the detection limit, C ¹ is 0 mass ppb.

Next, in Example D2, the amounts of the palladium atoms of the compound EM1 and the compound EM2 measured by the ICP / MS method are 14 mass ppb and the detection limit or less (that is, 0 mass ppb), respectively. The mass ratio of compound EM1 to compound EM2 is compound EM1: compound EM2 = 3: 7.
Therefore, C ¹ in Example D2 can be obtained from the amount of the palladium atom contained in the compound EM1 and the compound EM2 and the amount of the charged thereof, and is obtained as follows.
C ¹ = {14 × 3 / (3 + 7)} + {0 × 7 / (3 + 7)} = 4.2 mass ppb

Similarly, C ¹ in Example D4 is 0 mass ppb.

<Amount of palladium atom contained in host material ( ^CH )>
In the composition for a light emitting device of the present embodiment, the amount of palladium atoms ( ^CH ) contained in the host material is usually 9500 mass ppb or less with respect to the total amount of the host material. The phrase "amount of palladium atoms contained in the host material" does not mean that the host material contains palladium atoms, and the host material may or may not contain palladium atoms. good. In the host material of the present embodiment, the amount of the palladium atom is preferably 5000 mass ppb or less, more preferably 950 mass ppb or less, still more preferably, because the external quantum efficiency of the light emitting element of the present embodiment is more excellent. Is 500 mass ppb or less, and particularly preferably 95 mass ppb or less. Further, in the guest material of the present embodiment, the amount of the palladium atom may be 90 mass ppb or less, 60 mass ppb or less, 30 mass ppb or less, or 15 mass ppb or less. It may be 7 mass ppb or less, 3 mass ppb or less, 1 mass ppb or less, 0.5 mass ppb or less, 0. It may be 1 mass ppb or less, or may be 0 mass ppb.

The specific calculation method of CH can be obtained in the same manner as the specific calculation method of ^{C 1} described above.
For example, in Example D1, ^CH is 0 mass ppb. In Example D2, ^CH is 0 mass ppb. In Example D4, ^CH is 2.1 mass ppb.

<Method of reducing C ¹ and ^CH >
Examples of the method for reducing C ¹ and ^CH include purification.
For purification, 4th Edition Experimental Chemistry Course (1993, Maruzen), 5th Edition Experimental Chemistry Course (2007, Maruzen), New Experimental Chemistry Course (1975, Maruzen), Organic Chemistry Experiment Tebiki (1988) , Chemistry) and the like.

Purification includes, for example, sublimation, extraction, reprecipitation, recrystallization, chromatography and adsorption.
The purification of the low molecular weight guest material and the low molecular weight host material is preferably sublimation, recrystallization, chromatography or adsorption, more preferably sublimation or recrystallization, and more preferably, because the amount of palladium atoms can be further reduced. Is sublimation.
Purification of the polymer guest material and the polymer host material is preferably reprecipitation, chromatography or adsorption because the amount of palladium atoms can be further reduced.
In purification, when purification is performed more than once, the methods may be the same or different.

In sublimation, the degree of vacuum and the sublimation temperature may be appropriately set according to the material to be sublimated. The degree of vacuum is preferably 1 × 10 ^-10 Pa to 1 × 10 ⁵ Pa, more preferably 1 × 10 ^-7 Pa to 1 × 10 ² Pa, and further preferably 1 × 10 ^-5 Pa to 1 Pa. It is particularly preferably 1 × 10 ^-4 Pa to 1 × 10 − ² Pa. The sublimation temperature is preferably −100 ° C. to 1000 ° C., more preferably 0 ° C. to 700 ° C., still more preferably 100 ° C. to 500 ° C., and particularly preferably 200 ° C. to 350 ° C.

The extraction is preferably liquid separation or solid-liquid extraction with a Soxhlet extractor.

Examples of the solvent used for extraction include alcohol solvents such as methanol, ethanol, propanol, ethylene glycol, glycerin, 2-methoxyethanol and 2-ethoxyethanol; diethyl ether, tetrahydrofuran (THF), dioxane, cyclopentylmethyl ether and jigglime. Ether-based solvents such as; halogen-based solvents such as methylene chloride and chloroform; nitrile-based solvents such as acetonitrile and benzonitrile; hydrocarbon-based solvents such as hexane, decalin, toluene, xylene and mesitylen; N, N-dimethylformamide, N , N-dimethylacetamide and other amide solvents; acetone, dimethylsulfoxide, water and the like. The solvent may be used alone or in combination of two or more.

The chromatography is preferably column chromatography.
Silica gel or alumina is preferable as the filler used for column chromatography.
The example of the solvent used for chromatography is the same as the example of the solvent used for extraction.

The examples of the solvent used for reprecipitation and recrystallization are the same as the examples of the solvent used for extraction.

As the adsorption, treatment with an adsorbent is preferable. The adsorbent is preferably activated carbon, silica gel, alumina or Celite.
Treatment with an adsorbent is usually carried out in a solvent. The example of the solvent used for the treatment with the adsorbent is the same as the example of the solvent used for the extraction.

<Composition for light emitting element>
The composition for a light emitting device of this embodiment contains a host material and a guest material.
In the composition for a light emitting device of the present embodiment, the host material and the guest material may each contain only one kind or two or more kinds.
In the composition for a light emitting element of the present embodiment, the maximum peak wavelength of the emission spectrum of the host material at room temperature is preferably shorter than the maximum peak wavelength of the emission spectrum of the guest material at room temperature.
In the composition for a light emitting device of the present embodiment, the maximum peak wavelength of the light emission spectrum of the host material at room temperature is preferably 300 nm or more and 500 nm or less, more preferably 330 nm or more and 480 nm or less, and further preferably 360 nm or more and 460 nm or less. Is.
In the composition for a light emitting device of the present embodiment, the maximum peak wavelength of the light emission spectrum of the guest material at room temperature is preferably 380 nm or more and 500 nm or less, more preferably 400 nm or more and 490 nm or less, and further preferably 420 nm or more and 475 nm or less. Is.
For the maximum peak wavelength of the emission spectrum of the host material and guest material, the object to be measured is dissolved in an organic solvent such as xylene, toluene, chloroform, or tetrahydrofuran to prepare a dilute solution (1 × ^10-6 % by mass to 1 ×). ^10-3 % by mass), it can be evaluated by measuring the PL spectrum of the dilute solution at room temperature. Toluene or xylene is preferable as the organic solvent for dissolving the object to be measured.

In the composition for a light emitting element of the present embodiment, the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material is 86.5 mass ppb or less with respect to the total amount of the host material and the guest material. Since the external quantum efficiency of the light emitting element of this embodiment is more excellent, it is preferably 86.0 mass ppb or less, and more preferably 85.5 mass ppb or less. Further, in the composition for a light emitting element of the present embodiment, the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material is 75 mass ppb or less with respect to the total amount of the host material and the guest material. It may be 50 mass ppb or less, 30 mass ppb or less, 10 mass ppb or less, 5 mass ppb or less, or 3 mass ppb or less. It may be 1 mass ppb or less, 0.5 mass ppb or less, 0.1 mass ppb or less, or 0 mass ppb or less.

In this embodiment, the reason why the external quantum efficiency of the light emitting device is excellent is considered as follows.
The aromatic compound for a host material contained as a host material in the composition for a light emitting element of the present embodiment has a condensed ring skeleton in which only three or more benzene rings are condensed. The present inventors consider that such a fused ring skeleton electrically interacts with an aromatic compound for guest materials contained in the guest compound. On the other hand, the present inventors consider that the guest material aromatic compound contained as the guest material in the composition for the light emitting element of the present embodiment electrically interacts with the host material aromatic compound contained as the host material. thinking. Then, when the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material exceeds a predetermined amount in the composition for a light emitting element of the present embodiment, the present inventors cope with the above-mentioned interaction. , Palladium atoms have an adverse effect, and as a result, the emission characteristics, charge transport characteristics, or charge injection characteristics of the composition for a light emitting element of the present embodiment are deteriorated, or the charge balance of the light emitting element of the present embodiment is balanced. It is considered that the external quantum efficiency of the light emitting element of the present embodiment is lowered because it is destroyed.
Therefore, based on the above idea, the present inventors consider that, in the present embodiment, the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material is within a specific range, and the above-mentioned palladium atom is used. We believe that the effect will be suppressed and the effect of improving the external quantum efficiency of the light emitting element will be obtained.

The total amount (mass ppb) of the palladium atom contained in the host material and the palladium atom contained in the guest material is the ratio of the mass of the host material to the total mass of the host material and the guest material ^WH , and the host material and the guest material. When the ratio of the total mass of the guest material to the total mass of is W ¹ , it is expressed as C ^HWH + C ^{1 W 1} .
The ^WH is usually 0.01 to 0.9999, and is preferably 0.30 to 0.999, preferably 0.50 to 0.999, because the external quantum efficiency of the light emitting element of the present embodiment is more excellent. It is more preferably 995, further preferably 0.70 to 0.99, and particularly preferably 0.85 to 0.95.
W ¹ is usually 0.0001 to 0.99, and since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, it is preferably 0.001 to 0.70, preferably 0.005 to 0. It is more preferably 50, further preferably 0.01 to 0.30, and particularly preferably 0.05 to 0.15.

^A specific calculation method of ^WH and W1 will be described with reference to Examples D1 and D2 described later.

First, in Example D1, the mass ratio of compound H2 (host material) to compound EM2 (guest material) is compound H2: compound EM2 = 90:10.
Therefore, ^WH and ^W1 in Example D1 can be obtained from the amount of charge, and are obtained as follows.
^WH = 90 / (90 + 10) = 0.90
W ¹ = 10 / (90 + 10) = 0.10

In Example D2, the mass ratio of compound H2, compound EM1 and compound EM2 is compound H2: compound EM1: compound EM2 = 90: 3: 7.
Therefore, ^WH and ^W1 in Example D2 can be obtained from the amount of charge, and are obtained as follows.
^WH = 90 / (90 + 3 + 7) = 0.90
W ¹ = (3 + 7) / (90 + 3 + 7) = 0.10

Similarly, ^WH and W1 in Example ^D4 are obtained as follows.
^WH = (2 + 88) / (2 + 88 + 10) = 0.90
W ¹ = 10 / (2 + 88 + 10) = 0.10

As described above, C ^{H WH} + C ¹ W ¹ can be calculated by calculating C ¹ , ^CH , W ¹ and ^WH .

For example, ^{CHWH + C1 W1} in Example D1 is obtained as follows.
C ^{H WH} + C ¹ W ¹ = (0 x 0.90) + (0 x 0.10) = 0 mass ppb

For example, ^{CHWH + C1 W1} in Example D2 is obtained as follows.
C ^{H WH} + C ¹ W ¹ = (0 x 0.90) + (4.2 x 0.10) = 0.42 mass ppb

For example, ^CHWH + C ^{1 W 1} in Example D4 is obtained as follows.
C ^{H WH} + C ¹ W ¹ = (2.1 × 0.90) + (0 × 0.10) = 1.9 mass ppb

C ^{H WH} + C ¹ W ¹ is usually 86.5 mass ppb or less, and since the external quantum efficiency of the light emitting element of the present embodiment is more excellent, it is preferably 86.0 mass ppb or less, more preferably. It is 85.5 mass ppb or less. ^{CH WH +} C ¹ W ¹ may be 75 mass ppb or less, 50 mass ppb or less, 30 mass ppb or less, or 10 mass ppb or less. It may be 5 mass ppb or less, 3 mass ppb or less, 1 mass ppb or less, 0.5 mass ppb or less, 0.1 mass ppb or less. It may be 0 mass ppb.

(Other ingredients)
The composition for a light emitting device of this embodiment is selected from the group consisting of a host material, a guest material, a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material, an antioxidant, and a solvent. It may be a composition containing at least one material. However, the hole transport material, the hole injection material, the electron transport material, the electron injection material, and the light emitting material are different from the host material and the guest material.
The composition for a light emitting device of the present embodiment further contains at least one selected from the group consisting of a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material, an antioxidant and a solvent. In this case, it is preferable to reduce the amount of palladium atoms contained therein by the above-mentioned purification.

[ink]
A composition containing a host material, a guest material, and a solvent (hereinafter referred to as "ink") may be, for example, a spin coating method, a casting method, a micro gravure coating method, a gravure coating method, a bar coating method, or a roll. Light emitting elements using wet methods such as coating method, wire bar coating method, dip coating method, spray coating method, screen printing method, flexographic printing method, offset printing method, inkjet printing method, capillary coating method, nozzle coating method, etc. Suitable for fabrication. The viscosity of the ink may be adjusted depending on the type of printing method, but is preferably 1 mPa · s to 20 mPa · s at 25 ° C.
The solvent contained in the ink is preferably a solvent capable of dissolving or uniformly dispersing the solid content in the ink. Examples of the solvent include chlorine-based solvents, ether-based solvents, aromatic hydrocarbon-based solvents, aliphatic hydrocarbon-based solvents, ketone-based solvents, ester-based solvents, polyhydric alcohol-based solvents, alcohol-based solvents, sulfoxide-based solvents, and the like. Examples include amide-based solvents.
In the ink, the blending amount of the solvent is usually 1000 parts by mass to 100,000 parts by mass when the total of the host material and the guest material is 100 parts by mass.
The solvent may be used alone or in combination of two or more.

[Hole transport material]
The hole transport material is classified into a low molecular weight compound and a high molecular weight compound, and is preferably a high molecular weight compound having a cross-linking group.
Examples of the polymer compound include polyvinylcarbazole and its derivatives; polyarylene having an aromatic amine structure in its side chain or main chain and its derivatives. The polymer compound may be a compound to which an electron accepting site such as fullerene, tetrafluorotetracyanoquinodimethane, tetracyanoethylene and trinitrofluorenone is bound.
When the hole transporting material is contained in the composition for a light emitting device of the present embodiment, the blending amount of the hole transporting material is usually 1 part by mass when the total of the host material and the guest material is 100 parts by mass. ~ 400 parts by mass.
The hole transport material may be used alone or in combination of two or more.

[Electronic transport material]
Electron transport materials are classified into low molecular weight compounds and high molecular weight compounds. The electron transport material may have a cross-linking group.
Examples of the low molecular weight compound include metal complexes having 8-hydroxyquinoline as a ligand, oxadiazole, anthraquinonedimethane, benzoquinone, naphthoquinone, anthraquinone, tetracyanoanthraquinonedimethane, fluorenone, diphenyldicyanoethylene and diphenoquinone. , And these derivatives.
Examples of the polymer compound include polyphenylene, polyfluorene, and derivatives thereof. The polymer compound may be doped with a metal.
When the composition for a light emitting device of the present embodiment contains an electron transporting material, the blending amount of the electron transporting material is usually 1 part by mass to 400 parts when the total of the host material and the guest material is 100 parts by mass. It is a mass part.
The electron transport material may be used alone or in combination of two or more.

[Hole injection material and electron injection material]
Hole injection materials and electron injection materials are classified into low molecular weight compounds and high molecular weight compounds, respectively. The hole injection material and the electron injection material may have a cross-linking group.
Examples of the low molecular weight compound include metal phthalocyanines such as copper phthalocyanine; carbon; metal oxides such as molybdenum and tungsten; and metal fluorides such as lithium fluoride, sodium fluoride, cesium fluoride and potassium fluoride.
Examples of the polymer compound include polyaniline, polythiophene, polypyrrole, polyphenylene vinylene, polythienylene vinylene, polyquinoline and polyquinoxaline, and derivatives thereof; conductivity of polymers having an aromatic amine structure in the main chain or side chain. Examples include sex polymers.
When the hole injection material and / or the electron injection material is included in the composition for a light emitting element of the present embodiment, the blending amounts of the hole injection material and the electron injection material are the sum of the host material and the guest material, respectively. When it is 100 parts by mass, it is usually 1 part by mass to 400 parts by mass.
The hole injection material and the electron injection material may be used alone or in combination of two or more.

When the ion-doped hole injection material or electron injection material contains a conductive polymer, the electrical conductivity of the conductive polymer is preferably 1 × ^10-5 S / cm to 1 × 10 ³ S / cm. .. In order to keep the electric conductivity of the conductive polymer within such a range, an appropriate amount of ions can be doped into the conductive polymer. The type of ion to be doped is an anion in the case of a hole injection material and a cation in the case of an electron injection material. Examples of the anion include polystyrene sulfonic acid ion, alkylbenzene sulfonic acid ion, and cerebral sulfonic acid ion. Examples of the cation include lithium ion, sodium ion, potassium ion and tetrabutylammonium ion.
The type of ion to be doped may be used alone or in combination of two or more.

[Luminescent material]
Luminescent materials are classified into low molecular weight compounds and high molecular weight compounds. The light emitting material may have a cross-linking group.
Examples of the low molecular weight compound include naphthalene and its derivatives, anthracene and its derivatives, perylene and its derivatives, and triple-term luminescent complexes having iridium, platinum or europium as a central metal.
Examples of the polymer compound include an arylene group such as a phenylene group, a naphthalenediyl group, a fluorinatedyl group, a phenantrangeyl group, a dihydrophenantrenidyl group, an anthracendil group and a pyrenedyl group; two hydrogen atoms from an aromatic amine. Examples thereof include aromatic amine residues such as a group to be removed; and a polymer compound containing a divalent heterocyclic group such as a carbazolediyl group, a phenoxazidinediyl group and a phenothiazinediyl group.

In the composition for a light emitting device of the present embodiment, when a light emitting material is contained, the content of the light emitting material is usually 0.1 part by mass to 400 parts when the total of the host material and the guest material is 100 parts by mass. It is a mass part.
The luminescent material may be used alone or in combination of two or more.

[Antioxidant]
The antioxidant may be a compound that is soluble in the same solvent as the host material and the guest material and does not inhibit light emission and charge transport, and examples thereof include phenol-based antioxidants and phosphorus-based antioxidants.
When the composition for a light emitting device of the present embodiment contains an antioxidant, the blending amount of the antioxidant is usually 0.001 part by mass when the total of the host material and the guest material is 100 parts by mass. ~ 10 parts by mass.
The antioxidant may be used alone or in combination of two or more.

<Membrane>
The film contains the composition for a light emitting device of the present embodiment, and is suitable as a light emitting layer in the light emitting device. The film can be produced by a wet method using, for example, ink. Further, the film can be produced by, for example, a dry method such as a vacuum vapor deposition method. Examples of the method for producing the film by the dry method include a method of depositing the composition for a light emitting device of the present embodiment and a method of co-depositing a host material and a guest material.
The thickness of the film is usually 1 nm to 10 μm.

<Light emitting element>
The light emitting device of the present embodiment contains the above-mentioned composition for a light emitting device.
The configuration of the light emitting device of the present embodiment includes, for example, an anode, a cathode, and an organic layer containing the composition for the light emitting device of the present embodiment provided between the anode and the cathode.

[Layer structure]
The layer containing the composition for a light emitting device of the present embodiment is usually one or more layers selected from the group consisting of a light emitting layer, a hole transport layer, a hole injection layer, an electron transport layer, and an electron injection layer. , Preferably a light emitting layer. Each of these layers contains a light emitting material, a hole transporting material, a hole injecting material, an electron transporting material, and an electron injecting material. Each of these layers can form a light emitting material, a hole transporting material, a hole injecting material, an electron transporting material, and an electron injecting material by the same method as the above-mentioned film preparation.

The light emitting element has a light emitting layer between the anode and the cathode. From the viewpoint of hole injection and hole transportability, the light emitting element of the present embodiment preferably has at least one of a hole injection layer and a hole transport layer between the anode and the light emitting layer. From the viewpoint of electron injection and electron transportability, it is preferable to have at least one electron injection layer and an electron transport layer between the cathode and the light emitting layer.

The materials of the hole transport layer, the electron transport layer, the light emitting layer, the hole injection layer and the electron injection layer include the hole transport material and the electron transport material described above, respectively, in addition to the composition for the light emitting element of the present embodiment. Examples thereof include a light emitting material, a hole injection material, and an electron injection material.

The material of the hole transport layer, the material of the electron transport layer, and the material of the light emitting layer are used as a solvent used in forming the hole transport layer, the electron transport layer, and the layer adjacent to the light emitting layer, respectively, in the production of the light emitting element. When dissolved, it is preferable that the material has a cross-linking group in order to prevent the material from dissolving in the solvent. After forming each layer using a material having a cross-linking group, the layer can be insolubilized by cross-linking the cross-linking group.

In the light emitting element of the present embodiment, when a low molecular weight compound is used as a method for forming each layer such as a light emitting layer, a hole transport layer, an electron transport layer, a hole injection layer, and an electron injection layer, for example, a vacuum from a powder is used. Examples include a dry method such as a vapor deposition method, and a wet method such as a method by forming a film from a solution or a molten state. When a polymer compound is used, for example, a wet method such as a method by forming a film from a solution or a molten state can be mentioned. Be done. The order, number, and thickness of the layers to be laminated are adjusted in consideration of, for example, luminous efficiency and external quantum efficiency.

[Substrate / Electrode]
The substrate in the light emitting element may be a substrate that can form an electrode and does not chemically change when an organic layer is formed, and is, for example, a substrate made of a material such as glass, plastic, or silicon. In the case of an opaque substrate, it is preferable that the electrode farthest from the substrate is transparent or translucent.
Examples of the material of the anode include conductive metal oxides and translucent metals, preferably indium oxide, zinc oxide, tin oxide; indium tin oxide (ITO), indium zinc oxide and the like. Conductive compounds; composites of silver, palladium and copper (APC); NESA, gold, platinum, silver, copper.
Materials for the cathode include, for example, metals such as lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, aluminum, zinc, indium; two or more alloys thereof; one of them. Alloys of more than one species with one or more of silver, copper, manganese, titanium, cobalt, nickel, tungsten, tin; as well as graphite and graphite intercalation compounds. Examples of the alloy include magnesium-silver alloy, magnesium-indium alloy, magnesium-aluminum alloy, indium-silver alloy, lithium-aluminum alloy, lithium-magnesium alloy, lithium-indium alloy, and calcium-aluminum alloy.
The anode and cathode may each have a laminated structure of two or more layers.

The light emitting element of the present embodiment is suitable as a light source for a backlight of a liquid crystal display device, a light source for lighting, an organic EL lighting, a display device for a computer, a television, a portable terminal, or the like (for example, an organic EL display and an organic EL television). Can be used for.

Although a preferred embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

For example, one aspect of the present invention may relate to a method for producing a composition for a light emitting device in which a host material and a guest material are blended.

<Manufacturing method (1)>
In one embodiment, the method for producing a composition for a light emitting element includes a host material preparation step of preparing a host material containing an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed, and only hydrogen atoms and carbon atoms. In the guest material preparation step of preparing the guest material containing the aromatic compound composed of the above, and the host material and the guest material, the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material is 86.5 mass ppb or less. It may be a manufacturing method (hereinafter, also referred to as “manufacturing method (1)”) of a composition for a light emitting element, which comprises a manufacturing step of obtaining a composition for a light emitting element by mixing at a blending ratio of

In the production method (1), the host material preparation steps include a step (A-1) of preparing an aromatic compound having a fused ring skeleton in which only three or more benzene rings mixed with palladium atoms are condensed, and a step (A-). The step (A-2) of purifying at least a part of an aromatic compound having a fused ring skeleton in which only three or more benzene rings prepared in 1) are condensed to remove at least a part of a palladium atom is included. You can go out.

In the production method (1), the content of palladium atoms in the aromatic compound having a fused ring skeleton in which only three or more benzene rings prepared in the step (A-1) are condensed is not particularly limited, and is, for example, 95 mass. It may be ppb or more, 100 mass ppb or more, 250 mass ppb or more, 500 mass ppb or more, 1000 mass ppb or more, 5000 mass ppb or more. It may be 10,000 mass ppb or more, 50,000 mass ppb or more, or 100,000 mass ppb or more. Further, the upper limit of the content of the palladium atom in the aromatic compound having a fused ring skeleton in which only three or more benzene rings prepared in the step (A-1) are condensed is not particularly limited, and the content may be, for example,. It may be less than 10,000,000 mass ppb, may be less than 5,000,000 mass ppb, may be less than 1,000,000 mass ppb, and may be less than 500,000 mass ppb.

Examples of the purification method in the step (A-2) include the methods exemplified in the above ^- mentioned <Method for reducing C1 and ^CH >.

The content of palladium atoms in an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed after the step (A-2) is usually 9500 mass ppb or less, and is outside the light emitting element of the present embodiment. Since the quantum efficiency is more excellent, it is preferably 5000 mass ppb or less, more preferably 950 mass ppb or less, still more preferably 500 mass ppb or less, and particularly preferably 95 mass ppb or less. Further, the content of the palladium atom in the aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed after the step (A-2) may be 90 mass ppb or less, and may be 60 mass ppb or less. It may be 30 mass ppb or less, 15 mass ppb or less, 7 mass ppb or less, 3 mass ppb or less, or 1 mass ppb or less. It may be 0.5 mass ppb or less, 0.1 mass ppb or less, or 0 mass ppb or less.

In the production method (1), the guest material preparation step was prepared in the preparation step (B-1) for preparing an aromatic compound consisting only of hydrogen atoms and carbon atoms mixed with palladium atoms, and the step (B-1). It may include a step (B-2) of purifying at least a part of an aromatic compound consisting of only a hydrogen atom and a carbon atom to remove at least a part of a palladium atom.

In the production method (1), the content of the palladium atom in the aromatic compound consisting only of hydrogen atoms and carbon atoms prepared in the step (B-1) is not particularly limited, and may be, for example, 14 mass ppb or more. , 20 mass ppb or more, 50 mass ppb or more, 100 mass ppb or more, 500 mass ppb or more, 1000 mass ppb or more, 5000 mass ppb It may be 10000 mass ppb or more, 50,000 mass ppb or more, or 100,000 mass ppb or more. Further, the upper limit of the content of palladium atom in the aromatic compound consisting only of hydrogen atom and carbon atom prepared in the step (B-1) is not particularly limited, and the content is, for example, 10000000 mass ppb or less. It may be 5,000,000 mass ppb or less, 1,000,000 mass ppb or less, or 500,000 mass ppb or less.

Examples of the purification method in the step (B-2) include the methods exemplified in the above ^- mentioned <Method for reducing C1 and ^CH >.

Since the content of palladium atom in the aromatic compound consisting only of hydrogen atom and carbon atom after the step (B-2) is usually 1400 mass ppb or less, the external quantum efficiency of the light emitting element of this embodiment is more excellent. It is preferably 500 mass ppb or less, more preferably 140 mass ppb or less, further preferably 50 mass ppb or less, particularly preferably 25 mass ppb or less, and particularly preferably 14 mass ppb or less. It is particularly preferably 13 mass ppb or less, particularly preferably 10 mass ppb or less, and particularly preferably 7 ppb or less. Further, the content of the palladium atom in the aromatic compound consisting only of hydrogen atom and carbon atom after the step (B-2) may be 5 mass ppb or less, 2 mass ppb or less, and 1 The mass may be ppb or less, 0.5 mass ppb or less, 0.1 mass ppb or less, or 0 mass ppb or less.

In the manufacturing method (1), in the manufacturing process, the total amount of both is 86.5 mass ppb or less in consideration of the amount of palladium atoms contained in the host material and the amount of palladium atoms contained in the guest material. , Host material and guest material are mixed. Thereby, a composition for a light emitting device capable of improving the external quantum efficiency of the light emitting device can be obtained.
In the manufacturing process of the manufacturing method (1), the method of mixing the host material and the guest material is not particularly limited, but for example, the method of dissolving the host material and the guest material in the solvent described in the above-mentioned ink section and mixing them. , A method of mixing the host material and the guest material in a solid state, a method of mixing the host material and the guest material by co-evaporation, and the like.

The production method (1) may further include a host material measuring step for measuring the content of palladium atoms contained in the aromatic compound for the host material. The production method (1) may further include a guest material measuring step of measuring the content of palladium atoms contained in the aromatic compound for guest materials. The manufacturing method (1) preferably includes a host material measuring step and a guest material measuring step. The ICP / MS method is preferable as a method for measuring the content of palladium atoms in the host material measuring step and the guest material measuring step.
In the manufacturing method (1), it is preferable that the host material measuring step and the guest material measuring step are carried out before the manufacturing step.
In the manufacturing method (1), the host material preparation step preferably includes a host material measuring step. In the manufacturing method (1), the guest material preparation step preferably includes a guest material measuring step.

<Manufacturing method (2)>
In another embodiment, the method for producing a composition for a light emitting element includes a host material preparation step of preparing a host material containing an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed, and a guest for the host material. Palladium atoms contained in the host material with respect to the total amount of the host material and the guest material when mixed with the host material in the above compounding ratio, including a determination step to determine the compounding ratio of the material and an aromatic compound consisting only of hydrogen and carbon atoms. And the guest material preparation step of preparing the guest material in which the total amount of palladium atoms contained in the guest material is 86.5 mass ppb or less, and the host material and the guest material are mixed in a blending ratio to form a composition for a light emitting element. It may be a manufacturing method (hereinafter, also referred to as “manufacturing method (2)”) for a composition for a light emitting element, which comprises a manufacturing step of obtaining the above.

In the production method (2), the host material preparation steps include a step (A-1) of preparing an aromatic compound having a fused ring skeleton in which only three or more benzene rings mixed with palladium atoms are condensed, and a step (A-). The step (A-2) of purifying at least a part of an aromatic compound having a fused ring skeleton in which only three or more benzene rings prepared in 1) are condensed to remove at least a part of a palladium atom is included. You can go out. The step (A-1) and the step (A-2) in the manufacturing method (2) may be the same steps as the step (A-1) and the step (A-2) in the above-mentioned manufacturing method (1). ..

In the manufacturing method (2), in the determination step, the compounding ratio may be determined according to the characteristics of the light emitting element and the like. In the determination step, for example, the compounding ratio may be determined based on the result of manufacturing a light emitting element with a test composition using a material similar to the above-mentioned host material and guest material, and the content of palladium atom is 86.5. The compounding ratio may be determined based on the production result of the light emitting element with the test composition having a mass exceeding ppb.

In the production method (2), in the guest material preparation step, the palladium atom allowed in the guest material is determined by the content of palladium atoms in the host material prepared in the host material preparation step and the compounding ratio determined in the determination step. The content of the atom is determined. That is, it can be said that the guest material preparation step is a step of preparing a guest material having a palladium atom content within an allowable range.

In the production method (2), the guest material preparation step is, for example, a preparation step (B-1) for preparing an aromatic compound consisting only of hydrogen atoms and carbon atoms mixed with palladium atoms, and a step (B-1). It may include a step (B-2) of purifying at least a part of the prepared aromatic compound consisting only of a hydrogen atom and a carbon atom to remove at least a part of a palladium atom. The step (B-1) and the step (B-2) in the manufacturing method (2) may be the same steps as the step (B-1) and the step (B-2) in the above-mentioned manufacturing method (1). ..

In the manufacturing method (2), in the manufacturing process, the host material prepared in the host material preparation step and the guest material prepared in the guest material preparation step are mixed at a blending ratio determined in the determination step. This makes it possible to obtain a composition for a light emitting device having excellent external quantum efficiency of the light emitting device.
The method of mixing the host material and the guest material in the manufacturing process of the manufacturing method (2) may be the same as the method of mixing the host material and the guest material in the manufacturing process of the manufacturing method (1).

The manufacturing method (2) may further include the above-mentioned host material measuring step. The manufacturing method (2) may further include the guest material measuring step described above. The manufacturing method (2) preferably includes the above-mentioned host material measurement step and the above-mentioned guest material measurement step.
In the manufacturing method (2), it is preferable that the above-mentioned host material measuring step and the above-mentioned guest material measuring step are performed before the manufacturing step.
In the manufacturing method (2), the host material preparation step preferably includes the above-mentioned host material measuring step. In the manufacturing method (2), the guest material preparation step preferably includes the above-mentioned guest material measuring step.

<Manufacturing method (3)>
In still another embodiment, the method for producing a composition for a light emitting element includes a guest material preparation step of preparing a guest material containing an aromatic compound consisting only of hydrogen atoms and carbon atoms, and a compounding ratio of the host material to the guest material. Palladium contained in the host material with respect to the total amount of the host material and the guest material when mixed with the guest material in the above compounding ratio, including the determination step to determine and the aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed. A host material preparation step for preparing a host material in which the total amount of palladium atoms contained in the atoms and guest materials is 86.5 mass ppb or less, and the guest material and the host material are mixed in the above compounding ratio for a light emitting element. It may be a method for producing a composition for a light emitting element (hereinafter, also referred to as “production method (3)”), which comprises a production step for obtaining the composition.

In the production method (3), the guest material preparation step includes a step (B-1) of preparing an aromatic compound consisting only of a hydrogen atom and a carbon atom in which a palladium atom is mixed, and a hydrogen prepared in the step (B-1). It may include a step (B-2) of purifying at least a part of an aromatic compound consisting of only an atom and a carbon atom to remove at least a part of a palladium atom. The step (B-1) and the step (B-2) in the manufacturing method (3) may be the same steps as the step (B-1) and the step (B-2) in the above-mentioned manufacturing method (1). ..

In the manufacturing method (3), in the determination step, the compounding ratio may be determined according to the characteristics of the light emitting element and the like. In the determination step, for example, the compounding ratio may be determined based on the result of manufacturing a light emitting element with a test composition using a material similar to the above-mentioned host material and guest material, and the content of palladium atom is 86.5. The compounding ratio may be determined based on the production result of the light emitting element with the test composition having a mass exceeding ppb.

In the production method (3), in the host material preparation step, the palladium atom allowed in the host material is determined by the content of palladium atoms in the guest material prepared in the guest material preparation step and the compounding ratio determined in the determination step. The content of the atom is determined. That is, it can be said that the host material preparation step is a step of preparing a host material having a palladium atom content within an allowable range.

In the production method (3), the host material preparation step includes, for example, a preparation step (A-1) for preparing an aromatic compound having a fused ring skeleton in which only three or more benzene rings mixed with palladium atoms are condensed. The step (A-2) of purifying at least a part of the aromatic compound having a fused ring skeleton in which only three or more benzene rings prepared in (A-1) are condensed to remove at least a part of the palladium atom. , May be included. The step (A-1) and the step (A-2) in the manufacturing method (3) may be the same steps as the step (A-1) and the step (A-2) in the above-mentioned manufacturing method (1). ..

In the manufacturing method (3), in the manufacturing process, the guest material prepared in the guest material preparation step and the host material prepared in the host material preparation step are mixed at a blending ratio determined in the determination step. This makes it possible to obtain a composition for a light emitting device having excellent external quantum efficiency of the light emitting device.
The method of mixing the host material and the guest material in the manufacturing process of the manufacturing method (3) may be the same as the method of mixing the host material and the guest material in the manufacturing process of the manufacturing method (1).

The manufacturing method (3) may further include the above-mentioned host material measuring step. The manufacturing method (3) may further include the above-mentioned guest material measuring step. The manufacturing method (3) preferably includes the above-mentioned host material measurement step and the above-mentioned guest material measurement step.
In the manufacturing method (3), it is preferable that the above-mentioned host material measuring step and the above-mentioned guest material measuring step are performed before the manufacturing step.
In the production method (3), the host material preparation step preferably includes the above-mentioned host material measurement step. In the manufacturing method (3), the guest material preparation step preferably includes the guest material measuring step described above.

<Manufacturing method (4)>
In still another embodiment, the method for producing a composition for a light emitting element includes a host material preparation step of preparing an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed as a host material, and hydrogen as a guest material. When the guest material preparation step of preparing an aromatic compound consisting only of atoms and carbon atoms, the determination step of determining the blending ratio of the host material and the guest material, and the mixing ratio of the host material and the guest material at the above blending ratio, A fused ring skeleton in which only three or more benzene rings are condensed so that the total amount of palladium atoms contained in the host material and the palladium atoms contained in the guest material is 86.5 mass ppb or less with respect to the total amount of the host material and the guest material. A purification step of purifying at least a part of an aromatic compound having an aromatic compound and an aromatic compound consisting of only hydrogen atoms and carbon atoms, and a host material containing an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed and hydrogen. A method for producing a composition for a light emitting element, which comprises a manufacturing process for obtaining a composition for a light emitting element by mixing a guest material containing an aromatic compound consisting only of an atom and a carbon atom at the above compounding ratio (hereinafter, "" It may also be referred to as "manufacturing method (4)").

In the production method (4), only the aromatic compound having a fused ring skeleton in which three or more benzene rings prepared in the host material preparation step are condensed, and the hydrogen atoms and carbon atoms prepared in the guest material preparation step are used. A palladium atom may be mixed in at least one of the aromatic compounds. That is, the host material preparation step is a step of preparing an aromatic compound having a fused ring skeleton in which only three or more benzene rings in which palladium atoms are mixed are condensed, or the guest material preparation step is a step in which palladium atoms are mixed. It may be a step of preparing an aromatic compound consisting only of hydrogen atoms and carbon atoms.

In the manufacturing method (4), in the determination step, the compounding ratio may be determined according to the characteristics of the light emitting element and the like. In the determination step, for example, the compounding ratio may be determined based on the result of manufacturing a light emitting element with a test composition using a material similar to the above-mentioned host material and guest material, and the content of palladium atom is 86.5. The compounding ratio may be determined based on the production result of the light emitting element with the test composition having a mass exceeding ppb, and a fused ring skeleton in which only three or more benzene rings prepared in the host material preparation step and the guest material preparation step are condensed is formed. The compounding ratio may be determined based on the production result of a light emitting element with a test composition in which the aromatic compound having the aromatic compound and the aromatic compound consisting only of a hydrogen atom and a carbon atom are mixed.

In the production method (4), in the purification step, at least a part of an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed and an aromatic compound consisting of only hydrogen atoms and carbon atoms is purified. Examples of the purification method include the methods exemplified in the above-mentioned <Method for reducing C ¹ and ^CH >. The purification step may be a step of purifying only one of an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed and an aromatic compound consisting of only hydrogen atoms and carbon atoms, and only the benzene ring is used. It may be a step of purifying both an aromatic compound having a fused ring skeleton in which three or more are condensed and an aromatic compound consisting only of hydrogen atoms and carbon atoms.

In the production method (4), in the production step, an aromatic compound having a fused ring skeleton in which only three or more benzene rings are condensed and an aromatic compound consisting of only hydrogen atoms and carbon atoms are blended in a blending ratio determined in the determination step. Mix with. At this time, since the purification step has been performed, the total amount of the palladium atoms contained in the host material and the palladium atoms contained in the guest material is 86.5 mass ppb or less with respect to the total amount of the host material and the guest material. This makes it possible to obtain a composition for a light emitting device having excellent external quantum efficiency of the light emitting device.
The method of mixing the host material and the guest material in the manufacturing process of the manufacturing method (4) may be the same method as the method of mixing the host material and the guest material in the manufacturing process of the manufacturing method (1).

The manufacturing method (4) may further include the above-mentioned host material measuring step. The manufacturing method (4) may further include the guest material measuring step described above. The manufacturing method (4) preferably includes the above-mentioned host material measurement step and the above-mentioned guest material measurement step.
In the manufacturing method (4), it is preferable that the above-mentioned host material measuring step and the above-mentioned guest material measuring step are performed before the manufacturing step.
In the production method (4), the host material preparation step or the purification step preferably includes the above-mentioned host material measurement step. In the production method (4), the guest material preparation step or the purification step preferably includes the above-mentioned guest material measurement step.

Another aspect of the present invention relates to a method for manufacturing a light emitting device. This manufacturing method is a method for manufacturing a light emitting element including an anode, a cathode, and an organic layer provided between the anode and the cathode, and is manufactured by any of the above-mentioned manufacturing methods (1) to (4). It may be a method for manufacturing a light emitting element, which comprises a step of forming the organic layer with the composition for a light emitting element.
In the method for manufacturing a light emitting device of the present embodiment, the organic layer can be formed, for example, by using the same method as for forming the film described above.
Further, in the method for manufacturing a light emitting element of this embodiment, the manufacturing method described in the above-mentioned <Light emitting element> section may be used.
Further, as the light emitting element in the method for manufacturing the light emitting element of the present embodiment, for example, the light emitting element described in the above-mentioned <Light emitting element> section can be mentioned.

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

In this example, the maximum peak wavelength of the emission spectrum of the compound was measured at room temperature by a spectrophotometer (manufactured by JASCO Corporation, FP-6500). A xylene solution in which the compound was dissolved in xylene at a concentration of about 0.8 × 10 ^-4 % by mass was used as a sample. As the excitation light, UV light having a wavelength of 325 nm was used.

In this example, the amount of palladium atom contained in the compound was measured by the ICP / MASS method.

<Compound H1 and Compound EM1>
Compound H1 was synthesized according to the method described in JP-A-2011-105643.
Compound EM1 was synthesized according to the method described in International Publication No. 2011/137922.

The HPLC area percentage value of compound H1 was 99.5% or more. The amount of palladium atom ( ^CH ) contained in compound H1 was 95 mass ppb.
The HPLC area percentage value of compound EM1 was 99.5% or more. The amount of palladium atom (C ¹ ) contained in compound EM 1 was 14 mass ppb.

<Purification of compound H1 (synthesis of compound H2)>
Compound H2 was obtained by repeatedly sublimating and purifying compound H1 until the amount of palladium atoms contained in compound H1 was below the detection limit (0 mass ppb). At the time of sublimation purification, the degree of vacuum was set to 3 × 10 ^-3 Pa to 5 × 10 ^-3 Pa, and the sublimation temperature was set to 250 ° C to 300 ° C.
The HPLC area percentage value of compound H2 was 99.5% or more. Further, the amount (CH) of the palladium atom contained in the compound ^H2 was below the detection limit (0 mass ppb).

<Purification of compound EM1 (synthesis of compound EM2)>
Compound EM2 was obtained by repeatedly sublimating and purifying compound EM1 until the amount of palladium atoms contained in compound EM1 became below the detection limit (0 mass ppb). At the time of sublimation purification, the degree of vacuum was set to 3 × 10 ^-3 Pa to 5 × 10 ^-3 Pa, and the sublimation temperature was set to 250 ° C to 300 ° C.
The HPLC area percentage value of compound EM2 was 99.5% or more. In addition, the amount of palladium atom (C ¹ ) contained in compound EM 2 was below the detection limit (0 mass ppb).

The maximum peak wavelength of the emission spectra of the compounds H1 and H2 was 421 nm. The maximum peak wavelength of the emission spectra of the compounds EM1 and EM2 was 441 nm.

<Example D1> Fabrication and evaluation of light emitting device D1 (formation of anode and hole injection layer)
An anode was formed by attaching an ITO film to a glass substrate with a thickness of 45 nm by a sputtering method. ND-3202 (manufactured by Nissan Chemical Industries, Ltd.), which is a hole injection material, was formed on the anode to a thickness of 35 nm by a spin coating method. The substrate on which the hole injection layer was laminated was heated on a hot plate at 50 ° C. for 3 minutes in an atmospheric atmosphere, and further heated at 230 ° C. for 15 minutes to form a hole injection layer.

(Formation of hole transport layer)
The polymer compound HTL-1 was dissolved in xylene at a concentration of 0.7% by mass. Using the obtained xylene solution, a film was formed on the hole injection layer to a thickness of 20 nm by a spin coating method, and heated on a hot plate at 180 ° C. for 60 minutes in a nitrogen gas atmosphere. A hole transport layer was formed. The polymer compound HTL-1 is the polymer compound of Polymer Example 1 of International Publication No. 2014/102543.

(Formation of light emitting layer)
Compound H2 and compound EM2 (Compound H2 / Compound EM2 = 90% by mass / 10% by mass) were dissolved in toluene at a concentration of 2% by mass. Using the obtained toluene solution, a film was formed on the hole transport layer to a thickness of 60 nm by a spin coating method, and the light emitting layer was formed by heating at 130 ° C. for 10 minutes in a nitrogen gas atmosphere. ..

(Cathode formation)
After reducing the pressure of the substrate on which the light emitting layer is formed to 1.0 × 10 ^-4 Pa or less in the vapor deposition machine, sodium fluoride is placed on the light emitting layer at about 4 nm and then on the sodium fluoride layer as a cathode. Aluminum was deposited at about 80 nm. After the vapor deposition, the light emitting element D1 was manufactured by sealing with a glass substrate.

(Evaluation of light emitting element)
EL light emission was observed by applying a voltage to the light emitting element D1. The external quantum efficiency [%] at 0.075 mA / cm ² was measured.

<Examples D2 to D10 and Comparative Example CD1> Preparation and evaluation of light emitting elements D2 to D10 and CD1 “Compound H2 and compound EM2 (Compound H2 / Compound EM2 = 90% by mass /)” in Example D1 (formation of light emitting layer). Light emitting elements D2 to D10 and CD1 were produced in the same manner as in Example D1 except that the materials shown in Table 1 were used in the material ratios shown in Table 1 instead of 10% by mass).
EL light emission was observed by applying a voltage to the light emitting elements D2 to D10 and CD1. The external quantum efficiency [%] at 0.075 mA / cm ² of the light emitting devices D2 to D10 and CD1 was measured.

The results of Examples D1 to D10 and Comparative Example CD1 are shown in Table 1. The relative values of the external quantum efficiencies of the light emitting elements D1 to D10 are shown when the external quantum efficiency of the light emitting element CD1 is 1.0.

INDUSTRIAL APPLICABILITY According to the present invention, a composition useful for producing a light emitting device having excellent external quantum efficiency is provided. The present invention is industrially useful because it has effects such as resource saving and energy saving by manufacturing a light emitting element having excellent external quantum efficiency.

Claims (15)

A method for producing a composition for a light emitting device, which is a mixture of a host material and a guest material.
Host material preparation process and host material preparation process
A guest material preparation process for preparing a guest material containing an aromatic compound consisting only of hydrogen atoms and carbon atoms,
The host material and the guest material are mixed at a blending ratio such that the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material is 86.5 mass ppb or less to form a composition for a light emitting element. And the manufacturing process to get
Including
The guest material preparation process is
A step of preparing an aromatic compound consisting only of hydrogen atoms and carbon atoms having a palladium atom content of 14 mass ppb or more (B-1), and
At least a part of the aromatic compound consisting only of hydrogen atoms and carbon atoms prepared in the step (B-1) is purified, and consists only of hydrogen atoms and carbon atoms having a palladium atom content of 13 mass ppb or less. The step of obtaining an aromatic compound (B-2) and
A method for producing a composition for a light emitting device, which comprises. A method for producing a composition for a light emitting device, which is a mixture of a host material and a guest material.
Host material preparation process and host material preparation process
A determination step for determining the mixing ratio of the guest material to the host material, and
It contains an aromatic compound consisting only of hydrogen atoms and carbon atoms, and is contained in the palladium atom and the guest material contained in the host material with respect to the total amount of the host material and the guest material when mixed with the host material in the compounding ratio. A guest material preparation step for preparing a guest material and a guest material preparation step in which the total amount of palladium atoms is 86.5 mass ppb or less.
A manufacturing process for obtaining a composition for a light emitting device by mixing the host material and the guest material at the compounding ratio.
Including
The guest material preparation process is
A step of preparing an aromatic compound consisting only of hydrogen atoms and carbon atoms having a palladium atom content of 14 mass ppb or more (B-1), and
At least a part of the aromatic compound consisting only of hydrogen atoms and carbon atoms prepared in the step (B-1) is purified, and consists only of hydrogen atoms and carbon atoms having a palladium atom content of 13 mass ppb or less. The step of obtaining an aromatic compound (B-2) and
A method for producing a composition for a light emitting device, which comprises. A method for producing a composition for a light emitting device, which is a mixture of a host material and a guest material.
A guest material preparation process for preparing a guest material containing an aromatic compound consisting only of hydrogen atoms and carbon atoms,
A determination step for determining the mixing ratio of the host material to the guest material, and
When mixed with the guest material at the compounding ratio, the total amount of the palladium atom contained in the host material and the palladium atom contained in the guest material with respect to the total amount of the host material and the guest material is 86.5 mass ppb or less. Host material preparation process and host material preparation process
A manufacturing process for obtaining a composition for a light emitting device by mixing the guest material and the host material at the compounding ratio.
Including
The guest material preparation process is
A step of preparing an aromatic compound consisting only of hydrogen atoms and carbon atoms having a palladium atom content of 14 mass ppb or more (B-1), and
At least a part of the aromatic compound consisting only of hydrogen atoms and carbon atoms prepared in the step (B-1) is purified to consist only of hydrogen atoms and carbon atoms having a palladium atom content of 13 mass ppb or less. The step of obtaining an aromatic compound (B-2) and
A method for producing a composition for a light emitting device, which comprises. A method for producing a composition for a light emitting device, which is a mixture of a host material and a guest material.
Host material preparation process and host material preparation process
A guest material preparation process for preparing an aromatic compound consisting only of hydrogen atoms and carbon atoms as a guest material,
A determination step for determining the blending ratio of the host material and the guest material, and
When the host material and the guest material are mixed at the blending ratio, the total amount of palladium atoms contained in the host material and the palladium atom contained in the guest material relative to the total amount of the host material and the guest material is 86.5. A purification step of purifying at least a part of the aromatic compound consisting only of the host material and the hydrogen atom and the carbon atom so as to have a mass of ppb or less.
A manufacturing step of mixing the host material and the guest material containing an aromatic compound consisting only of hydrogen atoms and carbon atoms at the compounding ratio to obtain a composition for a light emitting element.
Including
The guest material preparation process is
A step of preparing an aromatic compound consisting only of hydrogen atoms and carbon atoms having a palladium atom content of 14 mass ppb or more (B-1), and
At least a part of the aromatic compound consisting only of hydrogen atoms and carbon atoms prepared in the step (B-1) is purified, and consists only of hydrogen atoms and carbon atoms having a palladium atom content of 13 mass ppb or less. The step of obtaining an aromatic compound (B-2) and
A method for producing a composition for a light emitting device, which comprises. The step (B-2) purifies at least a part of the aromatic compound consisting only of the hydrogen atom and the carbon atom prepared in the step (B-1), and the content of the palladium atom is 10 mass ppb or less. The method for producing a composition for a light emitting element according to any one of claims 1 to 4, which is a step of obtaining an aromatic compound consisting only of a hydrogen atom and a carbon atom. The step (B-2) purifies at least a part of the aromatic compound consisting only of the hydrogen atom and the carbon atom prepared in the step (B-1), and the content of the palladium atom is 7 mass ppb or less. The method for producing a composition for a light emitting element according to any one of claims 1 to 5, which is a step of obtaining an aromatic compound consisting only of a hydrogen atom and a carbon atom. The method for producing a composition for a light emitting element according to any one of claims 1 to 6, wherein the aromatic compound consisting only of a hydrogen atom and a carbon atom is a small molecule compound. The method for producing a composition for a light emitting element according to claim 7, wherein the aromatic compound consisting only of a hydrogen atom and a carbon atom is a compound represented by the formula (FB).

[During the ceremony,
n ^1B represents an integer of 0 or more.
Ar ^1B represents a group obtained by removing ^1B or more of hydrogen atoms directly bonded to carbon atoms constituting the aromatic hydrocarbon ring from the compound having an aromatic hydrocarbon ring.
R ^1B represents a hydrocarbon group consisting only of a hydrogen atom and a carbon atom, and this group may further have a substituent consisting only of a hydrogen atom and a carbon atom. When a plurality of the substituents are present, they may be the same or different, or they may be bonded to each other to form a ring with the atom to which each is bonded. When a plurality of R ^1Bs are present, they may be the same or different, or they may be bonded to each other to form a ring together with the carbon atoms to which they are bonded. ] The method for producing a composition for a light emitting element according to claim 8, wherein the aromatic hydrocarbon ring is a bicyclic to 7 ring type aromatic hydrocarbon ring. The aromatic hydrocarbon ring is a benzofluorene ring, a pyrene ring, a fluoranthene ring, a dibenzofluorene ring, a perylene ring, a benzofluoranthene ring, a spirobifluorene ring, a benzospirobifluorene ring or an acenaftfluoranthene ring. The method for producing a composition for a light emitting element according to claim 8 or 9. The hydrocarbon group consisting only of a hydrogen atom and a carbon atom is an alkyl group, a cycloalkyl group or an aryl group (these groups may have a substituent consisting only of a hydrogen atom and a carbon atom). The method for producing a composition for a light emitting element according to any one of claims 8 to 10. The guest material preparation step further includes a measuring step of measuring the content of a palladium atom contained in the aromatic compound consisting only of the hydrogen atom and the carbon atom obtained in the step (B-2), claim 1. The method for producing a composition for a light emitting element according to any one of 11 to 11. The guest material preparation step further includes a measurement step of measuring the content of palladium atoms contained in the aromatic compound consisting only of hydrogen atoms and carbon atoms prepared in the step (B-1), according to claims 1 to 1. 12. The method for producing a composition for a light emitting element according to any one of items 12. A composition for a light emitting element manufactured by the production method according to any one of claims 1 to 13, a hole transport material, a hole injection material, an electron transport material, an electron injection material, a light emitting material, and an antioxidant. A method for producing a composition for a light emitting element, which comprises a step of mixing with at least one selected from the group consisting of and a solvent. A method for manufacturing a light emitting device, comprising an anode, a cathode, and an organic layer provided between the anode and the cathode.
A method for manufacturing a light emitting device, which comprises a step of forming the organic layer with the composition for a light emitting device manufactured by the manufacturing method according to any one of claims 1 to 14.