JP5724554B2 - Light emitting device and resin composition for forming light emitting device - Google Patents

Description

  The present invention relates to a light emitting element and a resin composition for forming a light emitting element used as a material for forming a resin layer of the light emitting element.

The light emitting element has a basic configuration in which a transparent positive electrode layer, a light emitting material layer, and a negative electrode layer are laminated in this order on the surface of a transparent substrate. For example, an organic electroluminescence device injects holes from its positive electrode layer, electrons from its negative electrode layer, into a light emitting material layer made of an organic material, and regenerates holes and electrons inside the light emitting material layer. This is a light-emitting element that emits light by emission (fluorescence or phosphorescence) when excitons (excitons) are generated by combining them, and the excitons are deactivated. Light generated in the light emitting material layer is extracted from the transparent substrate side to the outside of the light emitting element.
Patent Document 1 discloses a light-emitting element having a high refractive index layer using a high refractive index resin such as polyethersulfone resin or polyetherimide resin.

JP 2004-296438 A

According to the light emitting element described in Patent Document 1, light generated in the light emitting material layer can be extracted from the transparent substrate side with some efficiency. However, there is a problem that high refractive index resins such as polyethersulfone resin and polyetherimide resin are deteriorated by light emitted from the light emitting material layer.
Therefore, an object of the present invention is to provide a light-emitting element that is excellent in light extraction efficiency and durability.

As a result of intensive studies to solve the above-mentioned problems, the present inventor achieved the above object according to a light emitting device comprising a resin layer comprising an aromatic polyether polymer having a specific glass transition temperature. As a result, the present invention has been completed.
That is, the present invention provides the following [1] to [8].

[1] A light emitting device comprising a substrate, a first electrode, a light emitting layer, a second electrode, and a resin layer,
The substrate, the first electrode, the light emitting layer, and the second electrode are laminated in this order,
The resin layer is
(A) a side of the first electrode opposite to the side on which the light emitting layer is formed; and
(B) The side of the second electrode opposite to the side on which the light emitting layer is formed,
Formed on at least one of
The resin layer is an aromatic polyether polymer (hereinafter referred to as “polymer (I)”) having a glass transition temperature (Tg) of 230 to 350 ° C. as measured by differential scanning calorimetry (DSC, heating rate 20 ° C./min). A light-emitting element including the layer.
[2] The light emitting device according to [1], wherein the light emitting device is an organic electroluminescence device.

  [3] The aromatic polyether polymer has at least one structural unit (i) selected from the group consisting of a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2). , [1] or [2].

（式（１）中、Ｒ¹〜Ｒ⁴は、それぞれ独立に炭素数１〜１２の１価の有機基を示し、ａ〜ｄは、それぞれ独立に０〜４の整数を示す。）

(In Formula (1), R < ¹ > -R < ⁴ > shows a C1-C12 monovalent organic group each independently, and ad shows the integer of 0-4 each independently.)

（式（２）中、Ｒ¹〜Ｒ⁴およびａ〜ｄは、それぞれ独立に前記式（１）中のＲ¹〜Ｒ⁴およびａ〜ｄと同義であり、Ｙは、単結合、−ＳＯ₂−または＞Ｃ＝Ｏを示し、Ｒ⁷およびＲ⁸は、それぞれ独立にハロゲン原子、炭素数１〜１２の１価の有機基またはニトロ基を示し、ｇおよびｈは、それぞれ独立に０〜４の整数を示し、ｍは、０または１を示す。但し、ｍが０の時、Ｒ⁷はシアノ基ではない。）

(In Formula (2), R < ¹ > -R < ⁴ > and ad are respectively synonymous with R < ¹ > -R < ⁴ > and said ad in said Formula (1), Y is a single bond, -SO _2- or> C = O, R ⁷ and R ⁸ each independently represent a halogen atom, a monovalent organic group having 1 to 12 carbon atoms or a nitro group, and g and h each independently represent 0 to 4 represents an integer of 4 and m represents 0 or 1. However, when m is 0, R ⁷ is not a cyano group.

  [4] The aromatic polyether polymer further includes at least one structural unit (ii) selected from the group consisting of a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4): The light-emitting device according to any one of [1] to [3],

（式（３）中、Ｒ⁵およびＲ⁶は、それぞれ独立に炭素数１〜１２の１価の有機基を示し、Ｚは、単結合、−Ｏ−、−Ｓ−、−ＳＯ₂−、＞Ｃ＝Ｏ、−ＣＯＮＨ−、−ＣＯＯ−または炭素数１〜１２の２価の有機基を示し、ｅおよびｆは、それぞれ独立に０〜４の整数を示し、ｎは０または１を示す。）

(In formula (3), R ⁵ and R ⁶ each independently represent a monovalent organic group having 1 to 12 carbon atoms, and Z represents a single bond, —O—, —S—, —SO ₂ —, > C═O, —CONH—, —COO— or a divalent organic group having 1 to 12 carbon atoms, e and f each independently represent an integer of 0 to 4, and n represents 0 or 1 .)

（式（４）中、Ｒ⁷、Ｒ⁸、Ｙ、ｍ、ｇおよびｈは、それぞれ独立に前記式（２）中のＲ⁷、Ｒ⁸、Ｙ、ｍ、ｇおよびｈと同義であり、Ｒ⁵、Ｒ⁶、Ｚ、ｎ、ｅおよびｆは、それぞれ独立に前記式（３）中のＲ⁵、Ｒ⁶、Ｚ、ｎ、ｅおよびｆと同義である。）

(In the formula ^{(4), R 7, R} 8, Y, m, g and h are each R ⁷ in independent to the formula ^{(2), R 8, Y} , m, synonymous with g and h, R ^5, R ^6, Z, n, e and f are as defined each R ⁵ in the formula (3) independently, R ^6, Z, n, e and f.)

[5] In the aromatic polyether polymer, any one of [1] to [4], wherein the molar ratio of the structural unit (i) to the structural unit (ii) is 50:50 to 100: 0. A light emitting device according to any one of the above.
[6] The method according to any one of [1] to [5], wherein the aromatic polyether-based polymer has a polystyrene-equivalent weight average molecular weight of 5,000 to 500,000 by gel permeation chromatography (GPC). Light emitting element.
[7] The light emitting device according to any one of [1] to [6], wherein the resin layer further contains metal oxide particles.

  [8] A polymer having at least one structural unit (i) selected from the group consisting of a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2), and an organic solvent: A resin composition for forming a light emitting device for forming a resin layer of the light emitting device.

（式（１）中、Ｒ¹〜Ｒ⁴は、それぞれ独立に炭素数１〜１２の１価の有機基を示し、ａ〜ｄは、それぞれ独立に０〜４の整数を示す。）

(In Formula (1), R < ¹ > -R < ⁴ > shows a C1-C12 monovalent organic group each independently, and ad shows the integer of 0-4 each independently.)

（式（２）中、Ｒ¹〜Ｒ⁴およびａ〜ｄは、それぞれ独立に前記式（１）中のＲ¹〜Ｒ⁴およびａ〜ｄと同義であり、Ｙは、単結合、−ＳＯ₂−または＞Ｃ＝Ｏを示し、Ｒ⁷およびＲ⁸は、それぞれ独立にハロゲン原子、炭素数１〜１２の１価の有機基またはニトロ基を示し、ｇおよびｈは、それぞれ独立に０〜４の整数を示し、ｍは、０または１を示す。但し、ｍが０の時、Ｒ⁷はシアノ基ではない。）

(In Formula (2), R < ¹ > -R < ⁴ > and ad are respectively synonymous with R < ¹ > -R < ⁴ > and said ad in said Formula (1), Y is a single bond, -SO _2- or> C = O, R ⁷ and R ⁸ each independently represent a halogen atom, a monovalent organic group having 1 to 12 carbon atoms or a nitro group, and g and h each independently represent 0 to 4 represents an integer of 4 and m represents 0 or 1. However, when m is 0, R ⁷ is not a cyano group.

The light-emitting element of the present invention includes a resin layer containing an aromatic polyether polymer having a specific glass transition temperature, and the resin layer has a high glass transition temperature, excellent transparency, and a high refractive index. , Has excellent light extraction efficiency.
Further, since the light-emitting element of the present invention is excellent in durability, it can be used without degrading performance for a long time even under severe use conditions.

It is sectional drawing which shows notionally Embodiment 1 of the light emitting element of this invention. It is sectional drawing which shows notionally Embodiment 2 of the light emitting element of this invention. It is sectional drawing which shows notionally Embodiment 3 of the light emitting element of this invention.

≪Light emitting element≫
Hereinafter, various exemplary embodiments of the light-emitting device of the present invention will be described with reference to the drawings. The light-emitting device includes a substrate, a first electrode, a light-emitting layer, a second electrode, and a resin layer.
The substrate, the first electrode, the light emitting layer, and the second electrode are laminated in this order,
The resin layer is an aromatic polyether polymer (hereinafter referred to as “polymer (I)”) having a glass transition temperature (Tg) of 230 to 350 ° C. as measured by differential scanning calorimetry (DSC, heating rate 20 ° C./min). It is also a layer containing
The resin layer is
(A) a side of the first electrode opposite to the side on which the light emitting layer is formed; and
(B) The side of the second electrode opposite to the side on which the light emitting layer is formed,
There is no particular limitation as long as the light emitting element is formed on at least one of the above.

  FIG. 1 shows a light emitting device 10 which is Embodiment 1 of the light emitting device of the present invention. The light emitting element 10 has a structure in which a substrate 11, a first electrode 13, a light emitting layer 15, a second electrode 17, and a resin layer 18 are laminated in this order. That is, the resin layer 18 is provided on the surface of the second electrode 17 opposite to the side on which the light emitting layer 15 is provided. The second electrode 17 is preferably a transmissive electrode. In this case, the light generated in the light emitting layer 15 can be extracted outside the light emitting element 10 through the second electrode 17 and the resin layer 18.

  The light emitting element 10 is preferably a light emitting element in which the refractive index of the second electrode 17, the refractive index of the resin layer 18, and the refractive index of air (about 1.0) decrease in this order. Moreover, it is preferable that the difference in refractive index between the second electrode 17 and the resin layer 18 and the difference in refractive index between the resin layer 18 and air are small. When the refractive indexes of the second electrode, the resin layer, and air have such a relationship, the interface between the second electrode 17 and the resin layer 18 is a process in which light generated in the light emitting layer 15 is extracted outside the light emitting element 10. Further, since it becomes difficult to totally reflect at the interface between the resin layer 18 and the air, it is considered that the light extraction efficiency is increased.

  As the substrate 11, a substrate used in a general light-emitting element can be used, but a glass substrate or a transparent substrate excellent in mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and waterproofness. A plastic substrate is preferred.

The first electrode 13 can be manufactured on the upper surface of the substrate 11 by vapor deposition or sputtering using a first electrode forming material. When forming a transmissive electrode, the first electrode forming material is transparent and has excellent conductivity, such as indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO ₂ ), zinc oxide ( ZnO) or the like can be used. When a reflective electrode is formed, magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—) are used as the first electrode forming material. In), magnesium-silver (Mg-Ag), or the like can be used. What is necessary is just to select the thickness of the 1st electrode 13 suitably according to the desired objective.

The light emitting layer 15 is formed of a material that exhibits a light emission phenomenon when an electric field is applied. Such materials include activated zinc sulfide ZnS: X (where X is an activated element such as Mn, Tb, Cu, Sm), CaS: Eu, SrS: Ce, SrGa ₂ S ₄ : Inorganic electroluminescent (EL) materials such as Ce, CaGa ₂ S ₄ : Ce, CaS: Pb, BaAl ₂ S ₄ : Eu, low molecular dyes such as aluminum complexes of 8-hydroxyquinoline, aromatic amines, anthracene single crystals Conjugated organic EL materials, poly (p-phenylenevinylene), poly [2-methoxy-5- (2-ethylhexyloxy) -1,4-phenylenevinylene], poly (3-alkylthiophene), polyvinylcarbazole, etc. Conventionally used EL materials such as polymer organic EL materials can be used. Among these, since the resin layer 18 contains the polymer (I), the light emitting layer 15 is preferably a layer formed using an organic EL material. The thickness of the light emitting layer 15 is 10-1000 nm normally, Preferably it is 30-500 nm, More preferably, it is 50-200 nm. The light emitting layer 15 can be formed by a vacuum film forming process such as vapor deposition or sputtering, or a coating process using chloroform or the like as a solvent.

  The second electrode 17 is preferably a cathode that is an electron injection electrode. The second electrode 17 can be manufactured by a vapor deposition method or a sputtering method using a second electrode forming material. As the second electrode forming substance, lithium (Li), magnesium (Mg), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg—Ag) and the like. A transmissive electrode can be obtained by forming a thin film from these substances. Further, a transmissive electrode containing ITO or IZO may be used. What is necessary is just to select the thickness of the 2nd electrode 17 suitably according to the desired objective.

  The resin layer 18 is a layer formed of a composition for forming a light emitting element, which contains the following polymer (I) and an organic solvent (hereinafter also referred to as “specific solvent”), and further contains metal oxide particles, if necessary. Preferably there is.

[Polymer (I)]
The polymer (I) is an aromatic polyether polymer having a glass transition temperature (Tg) of 230 to 350 ° C. as measured by differential scanning calorimetry (DSC, heating rate 20 ° C./min). The glass transition temperature of I) is preferably 240 to 330 ° C, more preferably 250 to 300 ° C.
The glass transition temperature of the polymer (I) is measured, for example, using a Rigaku 8230 type DSC measuring apparatus (temperature rising rate 20 ° C./min).

  A resin layer formed from such a resin composition for forming a light-emitting element comprising the polymer (I) is excellent in balance in heat resistance, mechanical strength, electrical characteristics, and the like.

  The polymer (I) is a polymer obtained by a reaction that forms an ether bond in the main chain, and is a structural unit represented by the following formula (1) (hereinafter also referred to as “structural unit (1)”) and the following. A polymer having at least one structural unit (i) selected from the group consisting of structural units represented by the formula (2) (hereinafter also referred to as “structural unit (2)”) (hereinafter also referred to as “polymer (II)”) It is preferable that When the polymer has the structural unit (i), an aromatic polyether polymer having a glass transition temperature of 230 to 350 ° C. is obtained. The resin layer formed from the resin composition for forming a light emitting element containing such a polymer (II) has excellent heat resistance, electrical characteristics, transparency, and a high refractive index. Moreover, when the resin layer contains the polymer (II), a light-emitting element having excellent light extraction efficiency and durability can be obtained.

In said formula (1), R < ¹ > -R < ⁴ > shows a C1-C12 monovalent organic group each independently. a to d each independently represent an integer of 0 to 4, preferably 0 or 1.
The monovalent organic group having 1 to 12 carbon atoms includes a monovalent hydrocarbon group having 1 to 12 carbon atoms and 1 to 1 carbon atoms containing at least one atom selected from the group consisting of an oxygen atom and a nitrogen atom. And 12 monovalent organic groups.

  Examples of the monovalent hydrocarbon group having 1 to 12 carbon atoms include a linear or branched hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and 6 to 12 carbon atoms. An aromatic hydrocarbon group etc. are mentioned.

  The linear or branched hydrocarbon group having 1 to 12 carbon atoms is preferably a linear or branched hydrocarbon group having 1 to 8 carbon atoms, and the linear or branched carbon group having 1 to 5 carbon atoms. A hydrogen group is more preferable.

  Preferable specific examples of the linear or branched hydrocarbon group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, and n-pentyl. Group, n-hexyl group, n-heptyl group and the like.

  As said C3-C12 alicyclic hydrocarbon group, a C3-C8 alicyclic hydrocarbon group is preferable, and a C3-C4 alicyclic hydrocarbon group is more preferable.

  Preferable specific examples of the alicyclic hydrocarbon group having 3 to 12 carbon atoms include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, and cyclohexyl group; cyclobutenyl group, cyclopentenyl group, and cyclohexenyl group. And the like. The bonding site of the alicyclic hydrocarbon group may be any carbon on the alicyclic ring.

  Examples of the aromatic hydrocarbon group having 6 to 12 carbon atoms include a phenyl group, a biphenyl group, and a naphthyl group. The bonding site of the aromatic hydrocarbon group may be any carbon on the aromatic ring.

  Examples of the organic group having 1 to 12 carbon atoms including an oxygen atom include an organic group consisting of a hydrogen atom, a carbon atom and an oxygen atom, and among them, a total carbon consisting of an ether bond, a carbonyl group or an ester bond and a hydrocarbon group. Preferable examples include organic groups of formulas 1 to 12.

  Examples of the organic group having 1 to 12 carbon atoms having an ether bond include an alkoxy group having 1 to 12 carbon atoms, an alkenyloxy group having 2 to 12 carbon atoms, an alkynyloxy group having 2 to 12 carbon atoms, and 6 to 12 carbon atoms. And an aryloxy group having 1 to 12 carbon atoms and the like. Specific examples include a methoxy group, an ethoxy group, a propoxy group, an isopropyloxy group, a butoxy group, a phenoxy group, a propenyloxy group, a cyclohexyloxy group, and a methoxymethyl group.

Moreover, as a C1-C12 organic group which has a carbonyl group, a C2-C12 acyl group etc. can be mentioned. Specific examples include an acetyl group, a propionyl group, an isopropionyl group, and a benzoyl group.
As a C1-C12 organic group which has an ester bond, a C2-C12 acyloxy group etc. are mentioned. Specific examples include an acetyloxy group, a propionyloxy group, an isopropionyloxy group, and a benzoyloxy group.

  Examples of the organic group having 1 to 12 carbon atoms including a nitrogen atom include an organic group consisting of a hydrogen atom, a carbon atom and a nitrogen atom, and specifically, a cyano group, an imidazole group, a triazole group, a benzimidazole group and a benzine. A triazole group etc. are mentioned.

  Examples of the organic group having 1 to 12 carbon atoms including an oxygen atom and a nitrogen atom include an organic group consisting of a hydrogen atom, a carbon atom, an oxygen atom and a nitrogen atom. Specifically, an oxazole group, an oxadiazole group, Examples include a benzoxazole group and a benzoxadiazole group.

As R < ¹ > -R < ⁴ > in said Formula (1), a C1-C12 monovalent hydrocarbon group is preferable, a C6-C12 aromatic hydrocarbon group is more preferable, and a phenyl group is further more preferable.

In the formula (2), R ¹ to R ⁴ and a~d are the same as R ¹ to R ⁴ and a~d each independently the formula (1), Y represents a single bond, -SO _2- or> C = O, R ⁷ and R ⁸ each independently represents a halogen atom, a monovalent organic group having 1 to 12 carbon atoms or a nitro group, and m represents 0 or 1. However, when m is 0, R ⁷ is not a cyano group. g and h each independently represent an integer of 0 to 4, preferably 0.
Examples of the monovalent organic group having 1 to 12 carbon atoms include the same organic groups as the monovalent organic group having 1 to 12 carbon atoms in the formula (1).

The polymer (II) has a molar ratio of the structural unit (1) to the structural unit (2) (however, the sum of the structural unit (1) and the structural unit (2) is 100). However, from the viewpoint of optical properties, heat resistance and mechanical properties, it is preferable that the structural unit (1): structural unit (2) = 50: 50 to 100: 0, and the structural unit (1): structural unit (2). = 70: 30 to 100: 0 is more preferable, and structural unit (1): structural unit (2) is more preferably 80:20 to 100: 0.
Here, the mechanical properties refer to properties such as the tensile strength, breaking elongation and tensile elastic modulus of the polymer.

  The polymer (II) further has at least one structural unit (ii) selected from the group consisting of a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4). May be. It is preferable that the polymer (II) has such a structural unit (ii) because the mechanical properties of the resin layer obtained from the composition having the polymer (II) are improved.

In the formula (3), R ⁵ and R ⁶ each independently represent a monovalent organic group having 1 to 12 carbon atoms, Z represents a single bond, —O—, —S—, —SO ₂ —, > C═O, —CONH—, —COO— or a divalent organic group having 1 to 12 carbon atoms, and n represents 0 or 1. e and f each independently represent an integer of 0 to 4, preferably 0.
Examples of the monovalent organic group having 1 to 12 carbon atoms include the same organic groups as the monovalent organic group having 1 to 12 carbon atoms in the formula (1).

  The divalent organic group having 1 to 12 carbon atoms includes a divalent hydrocarbon group having 1 to 12 carbon atoms, a divalent halogenated hydrocarbon group having 1 to 12 carbon atoms, an oxygen atom, and a nitrogen atom. A divalent organic group having 1 to 12 carbon atoms containing at least one atom selected from the above, and a divalent organic group having 1 to 12 carbon atoms containing at least one atom selected from the group consisting of an oxygen atom and a nitrogen atom. And halogenated organic groups.

  Examples of the divalent hydrocarbon group having 1 to 12 carbon atoms include a linear or branched divalent hydrocarbon group having 1 to 12 carbon atoms, a divalent alicyclic hydrocarbon group having 3 to 12 carbon atoms, and Examples thereof include a bivalent aromatic hydrocarbon group having 6 to 12 carbon atoms.

  Examples of the linear or branched divalent hydrocarbon group having 1 to 12 carbon atoms include a methylene group, an ethylene group, a trimethylene group, an isopropylidene group, a pentamethylene group, a hexamethylene group, and a heptamethylene group.

  Examples of the divalent alicyclic hydrocarbon group having 3 to 12 carbon atoms include cycloalkylene groups such as cyclopropylene group, cyclobutylene group, cyclopentylene group and cyclohexylene group; cyclobutenylene group, cyclopentenylene group and And cycloalkenylene groups such as a cyclohexenylene group.

  Examples of the divalent aromatic hydrocarbon group having 6 to 12 carbon atoms include a phenylene group, a naphthylene group, and a biphenylene group.

  Examples of the divalent halogenated hydrocarbon group having 1 to 12 carbon atoms include a linear or branched divalent halogenated hydrocarbon group having 1 to 12 carbon atoms and a divalent halogenated fat having 3 to 12 carbon atoms. Examples thereof include a cyclic hydrocarbon group and a divalent halogenated aromatic hydrocarbon group having 6 to 12 carbon atoms.

  Examples of the linear or branched divalent halogenated hydrocarbon group having 1 to 12 carbon atoms include a difluoromethylene group, a dichloromethylene group, a tetrafluoroethylene group, a tetrachloroethylene group, a hexafluorotrimethylene group, and a hexachlorotrimethylene group. Group, hexafluoroisopropylidene group, hexachloroisopropylidene group and the like.

  As the divalent halogenated alicyclic hydrocarbon group having 3 to 12 carbon atoms, at least a part of the hydrogen atoms exemplified in the divalent alicyclic hydrocarbon group having 3 to 12 carbon atoms is a fluorine atom. And a group substituted with a chlorine atom, a bromine atom or an iodine atom.

  As the divalent halogenated aromatic hydrocarbon group having 6 to 12 carbon atoms, at least a part of the hydrogen atoms exemplified in the divalent aromatic hydrocarbon group having 6 to 12 carbon atoms is a fluorine atom, chlorine And a group substituted with an atom, a bromine atom or an iodine atom.

  Examples of the organic group having 1 to 12 carbon atoms including at least one atom selected from the group consisting of an oxygen atom and a nitrogen atom include an organic group consisting of a hydrogen atom and a carbon atom and an oxygen atom and / or a nitrogen atom. And a divalent organic group having 1 to 12 carbon atoms and having an ether bond, a carbonyl group, an ester bond or an amide bond and a hydrocarbon group.

  The divalent halogenated organic group having 1 to 12 carbon atoms containing at least one kind of atom selected from the group consisting of oxygen atom and nitrogen atom is specifically selected from the group consisting of oxygen atom and nitrogen atom Examples include a group in which at least a part of the hydrogen atoms exemplified in the divalent organic group having 1 to 12 carbon atoms containing at least one atom is substituted with a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. .

Z in the formula (3) is preferably a single bond, —O—, —SO ₂ —,> C═O or a divalent organic group having 1 to 12 carbon atoms, and a divalent organic group having 1 to 12 carbon atoms. A hydrocarbon group, a divalent halogenated hydrocarbon group having 1 to 12 carbon atoms, or a divalent alicyclic hydrocarbon group having 3 to 12 carbon atoms is more preferable.

In the formula (4), R ⁷ , R ⁸ , Y, m, g and h are each independently synonymous with R ⁷ , R ⁸ , Y, m, g and h in the formula (2), R ^5, R ^6, Z, n, e and f are as defined each R ⁵ in the formula (3) independently, R ^6, Z, n, e and f. When m is 0, R ⁷ is not a cyano group.

In the polymer (II), the molar ratio of the structural unit (i) to the structural unit (ii) (however, the sum of both ((i) + (ii)) is 100) is an optical property. From the viewpoint of heat resistance and mechanical properties, (i) :( ii) = 50: 50 to 100: 0 is preferable, and (i) :( ii) = 70: 30 to 100: 0. More preferably, (i) :( ii) = 80: 20 to 100: 0 is more preferable.
Here, the mechanical properties refer to properties such as the tensile strength, breaking elongation and tensile elastic modulus of the polymer.

  The polymer (II) preferably contains 70 mol% or more of the structural unit (i) and the structural unit (ii) in the total structural units from the viewpoint of optical properties, heat resistance and mechanical properties. It is more preferable to contain 95 mol% or more.

  The polymer (II) includes, for example, a compound represented by the following formula (5) (hereinafter also referred to as “compound (5)”) and a compound represented by the following formula (7) (hereinafter referred to as “compound (7)”). A component containing at least one compound selected from the group consisting of (hereinafter also referred to as “component (A)”) and a component containing a compound represented by the following formula (6) (hereinafter referred to as “component (B)”) It can also be obtained by reacting.

  In said formula (5), X shows a halogen atom independently and a fluorine atom is preferable.

In the formula ^{(7), R 7, R} 8, Y, m, g and h are each R ⁷ in independent to the formula ^{(2), R 8, Y} , m, synonymous with g and h, X is independently synonymous with X in the formula (5).
However, when m is 0, R ⁷ is not a cyano group.

In the formula (6), each R ^a independently represents a hydrogen atom, a methyl group, an ethyl group, an acetyl group, a methanesulfonyl group or a trifluoromethylsulfonyl group, and among them, a hydrogen atom is preferable. In the formula (6), R ¹ to R ⁴ and a~d have the same meanings as R ¹ to R ⁴ and a~d each independently the formula (1).

  Specific examples of the compound (5) include 2,6-difluorobenzonitrile (DFBN), 2,5-difluorobenzonitrile, 2,4-difluorobenzonitrile, 2,6-dichlorobenzonitrile, 2, Mention may be made of 5-dichlorobenzonitrile, 2,4-dichlorobenzonitrile and their reactive derivatives. In particular, 2,6-difluorobenzonitrile and 2,6-dichlorobenzonitrile are preferably used from the viewpoints of reactivity and economy. These compounds can be used in combination of two or more.

  Specific examples of the compound represented by the above formula (6) (hereinafter also referred to as “compound (6)”) include 9,9-bis (4-hydroxyphenyl) fluorene (BPFL) and 9,9-bis. (3-phenyl-4-hydroxyphenyl) fluorene, 9,9-bis (3,5-diphenyl-4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 9, Examples include 9-bis (4-hydroxy-3,5-dimethylphenyl) fluorene, 9,9-bis (4-hydroxy-3-cyclohexylphenyl) fluorene, and reactive derivatives thereof. Among the above-mentioned compounds, 9,9-bis (4-hydroxyphenyl) fluorene and 9,9-bis (3-phenyl-4-hydroxyphenyl) fluorene are preferably used. These compounds can be used in combination of two or more.

  Specific examples of the compound (7) include 4,4′-difluorobenzophenone, 4,4′-difluorodiphenylsulfone (DFDS), 2,4′-difluorobenzophenone, 2,4′-difluorodiphenylsulfone, 2,2′-difluorobenzophenone, 2,2′-difluorodiphenylsulfone, 3,3′-dinitro-4,4′-difluorobenzophenone, 3,3′-dinitro-4,4′-difluorodiphenylsulfone, 4, 4'-dichlorobenzophenone, 4,4'-dichlorodiphenyl sulfone, 2,4'-dichlorobenzophenone, 2,4'-dichlorodiphenyl sulfone, 2,2'-dichlorobenzophenone, 2,2'-dichlorodiphenyl sulfone, 3 , 3′-dinitro-4,4′-dichlorobenzophenone and 3,3′-dinitro-4, 4'-dichlorodiphenyl sulfone and the like can be mentioned. Among these, 4,4′-difluorobenzophenone and 4,4′-difluorodiphenyl sulfone are preferable. These compounds can be used in combination of two or more.

It is preferable that at least one compound selected from the group consisting of compound (5) and compound (7) is contained in 80 mol% to 100 mol% in 100 mol% of component (A), and 90 mol% to More preferably, it is contained at 100 mol%.
Moreover, it is preferable that (B) component contains the compound represented by following formula (8) as needed. Compound (6) is preferably contained in 100 mol% of component (B) in an amount of 50 mol% to 100 mol%, more preferably 80 mol% to 100 mol%, and more preferably 90 mol%. More preferably, it is contained in an amount of ˜100 mol%.

In the formula (8), R ⁵ , R ⁶ , Z, n, e and f are each independently synonymous with R ⁵ , R ⁶ , Z, n, e and f in the formula (3), R ^a has the same meaning as R ^a each independently in the formula (6) in.

  Examples of the compound represented by the formula (8) include hydroquinone, resorcinol, 2-phenylhydroquinone, 4,4′-biphenol, 3,3′-biphenol, 4,4′-dihydroxydiphenylsulfone, and 3,3′-dihydroxy. Diphenylsulfone, 4,4′-dihydroxybenzophenone, 3,3′-dihydroxybenzophenone, 1,1′-bi-2-naphthol, 1,1′-bi-4-naphthol, 2,2-bis (4-hydroxy) Phenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane and reactive derivatives thereof Etc. Among the above-mentioned compounds, resorcinol, 4,4′-biphenol, 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (4-hydroxy) Phenyl) -1,1,1,3,3,3-hexafluoropropane is preferred, and 4,4′-biphenol is suitably used from the viewpoint of reactivity and mechanical properties. These compounds can be used in combination of two or more.

More specifically, the polymer (II) can be synthesized by the method (I ′) shown below.
Method (I ′):
The alkali metal salt obtained after reacting the component (B) with an alkali metal compound in an organic solvent to obtain an alkali metal salt of the component (B) (compound (6) and / or compound (8), etc.) And (A) component are made to react. In addition, the alkali metal salt of (B) component and (A) component can also be made to react by performing reaction with (B) component and an alkali metal compound in presence of (A) component.

  Examples of the alkali metal compound used in the reaction include alkali metals such as lithium, potassium and sodium; alkali hydrides such as lithium hydride, potassium hydride and sodium hydride; lithium hydroxide, potassium hydroxide and sodium hydroxide And alkali metal carbonates such as lithium hydrogen carbonate, potassium hydrogen carbonate and sodium hydrogen carbonate. These can be used alone or in combination of two or more.

In the alkali metal compound, the amount of metal atoms in the alkali metal compound is usually 1 to 3 times equivalent, preferably 1.1 to 2 times equivalent to all —O—R ^a in the component (B). Preferably it is used in an amount of 1.2 to 1.5 times equivalent.

  Examples of the organic solvent used in the reaction include N, N-dimethylacetamide (DMAc), N, N-dimethylformamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, γ- Butyllactone, sulfolane, dimethyl sulfoxide, diethyl sulfoxide, dimethyl sulfone, diethyl sulfone, diisopropyl sulfone, diphenyl sulfone, diphenyl ether, benzophenone, dialkoxybenzene (1 to 4 carbon atoms of alkoxy group) and trialkoxybenzene (carbon number of alkoxy group) 1-4) etc. can be used. Among these solvents, polar organic solvents having a high dielectric constant such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, sulfolane, diphenylsulfone, and dimethylsulfoxide are particularly preferably used.

  Further, in the reaction, a solvent azeotropic with water such as benzene, toluene, xylene, hexane, cyclohexane, octane, chlorobenzene, dioxane, tetrahydrofuran, anisole and phenetole can be further used.

  The proportion of component (A) and component (B) used is preferably 45 mol% or more and 55 mol% or less when component (A) is 100 mol% in total of component (A) and component (B). More preferably, it is 50 mol% or more and 52 mol% or less, more preferably more than 50 mol% and 52 mol% or less, and the component (B) is preferably 45 mol% or more and 55 mol% or less, more preferably 48 mol%. % Or more and 50 mol% or less, more preferably 48 mol% or more and less than 50 mol%.

  Moreover, reaction temperature becomes like this. Preferably it is 60-250 degreeC, More preferably, it is the range of 80-200 degreeC. The reaction time is preferably in the range of 15 minutes to 100 hours, more preferably 1 hour to 24 hours.

  The polymer (I) is a polystyrene-reduced weight average molecular weight (Mw) measured by a TOSOH HLC-8220 GPC apparatus (column: TSKgel α-M, developing solvent: tetrahydrofuran (hereinafter also referred to as “THF”)). However, Preferably it is 5,000-500,000, More preferably, it is 15,000-400,000, More preferably, it is 30,000-300,000.

  The polymer (I) has a thermal decomposition temperature measured by thermogravimetric analysis (TGA) of preferably 450 ° C. or higher, more preferably 475 ° C. or higher, and further preferably 490 ° C. or higher.

As the resin composition for forming a light emitting element, a mixture of the polymer (II) obtained by the method (I ′) and an organic solvent can be used as it is. In this case, the organic solvent used for the reaction is a specific solvent.
The composition is prepared by isolating (purifying) the polymer (II) as a solid component from the mixture of the polymer (II) obtained by the above method and an organic solvent, and then re-dissolving it in a specific solvent. It can also be prepared.

  The method of isolating (purifying) the polymer (II) as a solid component is, for example, reprecipitation of the polymer in a poor solvent of the polymer such as methanol, and then filtering, and then drying the filtrate under reduced pressure. Can be performed.

  As the specific solvent for redissolving the polymer (II), a solvent that easily dissolves the polymer (II) is preferably selected. For example, methylene chloride, tetrahydrofuran, cyclohexanone, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone and γ-butyrolactone are preferably used, and from the viewpoint of coating properties and economy, Methylene chloride, cyclohexanone, N, N-dimethylacetamide and N-methylpyrrolidone are preferably used. These solvents can be used alone or in combination of two or more.

  In addition, other specific solvents such as ether organic solvents, ester organic solvents, ketone organic solvents, hydrocarbon organic solvents, alcohols, aiming to improve drying properties, uniformity and surface smoothness during coating. One kind selected from organic organic solvents, or two or more kinds of solvents can be used in appropriate combination. In this case, an organic solvent having a boiling point in the range of 40 to 250 ° C., more preferably 50 to 150 ° C. under atmospheric pressure (1,013 hPa) is preferable, and the polymer (II) is uniformly dissolved and dispersed. It is preferable to be used within the range where it can be used.

  Preferred examples of these other specific solvents include glycol ethers such as ethylene glycol monoethyl ether and propylene glycol monomethyl ether; ethylene glycol alkyl ether acetates such as ethyl cellosolve acetate, propylene glycol methyl ether acetate and propylene glycol ethyl ether acetate. Esters such as ethyl lactate and ethyl 2-hydroxypropionate; diethylene glycols such as diethylene glycol monomethyl ether, diethylene glycol dimethyl ether and diethylene glycol ethyl methyl ether; ketones such as methyl ethyl ketone, methyl isobutyl ketone, 2-heptanone, cyclohexanone and methyl amyl ketone Class: γ-butyrolactone It is.

  In addition, the said specific solvent is used suitably also for the resin composition for light emitting element formation containing polymer (I).

  The concentration of the polymer (I) in the resin composition for light emitting element formation is usually 1 to 40% by mass, preferably 5 to 25% by mass, although it depends on the molecular weight of the polymer. When the concentration of the polymer (I) in the composition is in the above range, it is possible to form a resin layer that can be thickened, hardly causes pinholes, and has excellent surface smoothness.

  The viscosity of the resin composition for forming a light emitting element is preferably 50 to 100,000 mPa · s, more preferably 500 to 50,000 mPa · s, and still more preferably 1000, although it depends on the molecular weight and concentration of the polymer. ˜20,000 mPa · s. When the viscosity of the composition is in the above range, the composition is easily retained during formation of the layer, and the thickness can be easily adjusted. Therefore, the resin layer can be easily molded.

Moreover, an anti-aging agent can be further contained in the resin composition for forming a light emitting element, and the durability of the resulting resin layer can be further improved by containing the anti-aging agent.
Preferred examples of the antiaging agent include hindered phenol compounds.

  Examples of hindered phenol compounds that can be used in the present invention include triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) proonate], 1,6-hexanediol- Bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-tert- Butylanilino) -3,5-triazine, pentaerythritol tetrakis [3- (3,5-tert-butyl-4-hydroxyphenyl) propionate], 1,1,3-tris [2-methyl-4- [3- ( 3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] -5-tert-butylphenyl] butane 2,2-thio-diethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) Propionate), N, N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide), 1,3,5-trimethyl-2,4,6-tris (3,5 -Di-tert-butyl-4-hydroxybenzyl) benzene, tris- (3,5-di-tert-butyl-4-hydroxybenzyl) -isocyanurate and 3,9-bis [2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro 5.5] undecane, and the like.

  In this invention, it is preferable to use an anti-aging agent in the quantity of 0.01-10 weight part with respect to 100 weight part of said polymers (I).

[Metal oxide particles]
In order to obtain a resin layer having a higher refractive index, metal oxide particles having a higher refractive index can be blended with the resin composition for forming a light emitting element. Such metal oxide particles are fine particles having a refractive index of light having a wavelength of 400 nm at 25 ° C. of preferably 1.55 or more, more preferably 1.60 or more, and particularly preferably 1.70 or more. Examples of the metal oxide particles include metal oxide particles such as zirconium oxide, titanium oxide, zinc oxide, tantalum oxide, indium oxide, hafnium oxide, tin oxide, niobium oxide, and composites thereof. Among these, fine particles of zirconium oxide (ZrO ₂ ) are preferable.
The titanium oxide is not particularly limited as long as it has a TiO ₂ structure, and examples thereof include anatase type, rutile type and brookite type.
These metal oxide particles can be used alone or in combination of two or more.

The number average primary particle diameter of the metal oxide particles is preferably 1 to 100 nm, more preferably 3 to 70 nm, and particularly preferably 5 to 50 nm. When the number average primary particle diameter is within the above range, a resin layer having excellent transparency can be obtained.
The metal oxide particles may be in the form of a powder or a solvent-dispersed sol. The solvent-dispersed sol includes, for example, 2-butanol, methanol, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, N-methyl-2-pyrrolidone, and propylene glycol monomethyl ether as a solvent.

The blending amount of the metal oxide particles is not particularly limited as long as the transparency of the resulting resin layer is not impaired, but the concentration of the polymer (I) in the resin composition and the viscosity of the resin composition are within the above ranges. The amount is preferably such that specifically, 0 to 2,000, preferably 10 to 1,500 parts by mass, and more preferably 30 to 1,000 parts by mass with respect to 100 parts by mass of the polymer (I). Part, more preferably 50 to 500 parts by mass. When the blending amount of the metal oxide particles is in the above range, the refractive index of the resin layer can be adjusted to a desired value while maintaining transparency and crack resistance.
When the metal oxide particles to be used are a solvent-dispersed sol, the compounding amount of the metal oxide particles means a mass not including a solvent, and the amount of the solvent contained in the sol is the amount of the specific solvent. Count.

  When the metal oxide particles are blended in the light emitting element forming resin composition, the volume average particle size in the composition is preferably 1 to 400 nm, more preferably 3 to 200 nm, and still more preferably 5 to 100 nm. Most preferably, it is 5-50 nm. When the volume average particle size is within the above range, a resin layer having excellent transparency can be obtained.

[Dispersant]
When the said metal oxide particle is mix | blended, it is preferable that the said resin composition for light emitting element formation contains various dispersing agents, in order to improve the dispersibility of a metal oxide particle.
As the dispersant, for example, an aluminum compound can be used. Examples of the aluminum compound include aluminum alkoxide and aluminum β-diketonate complex. Specifically, alkoxide compounds such as triethoxyaluminum, tri (n-propoxy) aluminum, tri (i-propoxy) aluminum, tri (n-butoxy) aluminum, tri (sec-butoxy) aluminum, aluminum tris (methylacetate) Acetate), aluminum tris (ethyl acetoacetate), tris (acetoacetonato) aluminum, aluminum monoacetylacetonatobis (methyl acetate), aluminum monoacetylacetonatobis (ethyl acetate) and other β-diketonate complexes .

  Commercial products of aluminum compounds include AIPD, PADM, AMD, ASBD, aluminum ethoxide, ALCH, ALCH-50F, ALCH-75, ALCH-TR, ALCH-TR-20, aluminum chelate M, aluminum chelate D, aluminum chelate A (W), surface treatment agent OL-1000, algomer, algomer 800AF, algomer 1000SF (manufactured by Kawaken Fine Chemical Co., Ltd.) and the like.

A nonionic dispersant can also be used as the dispersant. By using a nonionic dispersant, the dispersibility of the metal oxide particles can be enhanced. A preferred example of the nonionic dispersant is a phosphoric ester nonionic dispersant having a polyoxyethylene alkyl structure.
The blending amount of the dispersant is not particularly limited as long as the effects of the present invention are not impaired. However, when the dispersant is included, for example, 0.1% with respect to 100% by mass of the total component of the composition excluding the specific solvent. ˜5 mass%.

[Dispersion aid]
The composition for forming a light emitting element preferably further contains a dispersion aid in order to enhance the dispersibility of the metal oxide particles. As the dispersion aid, one or more selected from acetylacetone, N, N-dimethylacetoacetamide and the like can be suitably used.
The blending amount of the dispersion aid is not particularly limited as long as the effects of the present invention are not impaired. However, when the dispersion aid is included, the amount of the dispersion aid is, for example, 0. 1 to 5% by mass.

[Surfactant]
When the metal oxide particles are blended in the light emitting element forming resin composition, it is preferable to blend a surfactant from the viewpoint of obtaining a resin layer having a uniform thickness. Examples of the surfactant include a silicone-based surfactant and a fluorine-based surfactant. Of these, silicone surfactants are preferred.

  Examples of silicone surfactants include, for example, SH28PA (Toray Dow Corning, dimethylpolysiloxane polyoxyalkylene copolymer), Paintad 19, Paintad 54 (Toray Dow Corning, dimethylpolysiloxane polyoxyalkylene). Copolymer), FM0411 (Silaplane, manufactured by Chisso), SF8428 (manufactured by Toray Dow Corning, dimethylpolysiloxane polyoxyalkylene copolymer (containing OH group in side chain)), BYKUV3510 (manufactured by BYK Chemie Japan, Dimethylpolysiloxane-polyoxyalkylene copolymer), DC57 (manufactured by Toray Dow Corning Silicone, dimethylpolysiloxane-polyoxyalkylene copolymer), DC190 (manufactured by Toray Dow Corning Silicone, Methylpolysiloxane-polyoxyalkylene copolymer), Silaplane FM-4411, FM-4421, FM-4425, FM-7711, FM-7721, FM-7725, FM-0411, FM-0421, FM-0425, FM-DA11, FM-DA21, FM-DA26, FM0711, FM0721, FM-0725, TM-0701, TM-0701T (manufactured by Chisso), UV3500, UV3510, UV3530 (manufactured by Big Chemie Japan), BY16-004, SF8428 (made by Toray Dow Corning Silicone), VPS-1001 (made by Wako Pure Chemical Industries), etc. are mentioned. Particularly preferred examples include Silaplane FM-7711, FM-7721, FM-7725, FM-0411, FM-0421, FM-0425, FM0711, FM0721, FM-0725, VPS-1001, and the like. Moreover, as a commercial item of the silicone compound which has an ethylenically unsaturated group, TegoRad2300, 2200N (made by Tego Chemie) etc. are mentioned, for example.

  Examples of the fluorosurfactant include, for example, MegaFuck F-114, F410, F411, F450, F493, F494, F443, F444, F445, F446, F470, F471, F472SF, F474, F475, R30, F477, F478, F479, F480SF, F482, F483, F484, F486, F487, F172D, F178K, F178RM, ESM-1, MCF350SF, BL20, R08, R61, R90 (manufactured by DIC) can be mentioned.

  The blending ratio of the surfactant is preferably 0 to 10% by mass, more preferably 0.1 to 5% by mass, and particularly preferably 0.5% with respect to 100% by mass of the total amount of components of the composition excluding the specific solvent. ˜3 mass%. When the compounding amount of the surfactant exceeds 10% by mass with respect to 100% by mass of the total component of the composition excluding the specific solvent, the refractive index of the resulting resin layer may be lowered.

[Other additives]
The said resin composition for light emitting element formation can contain various additives other than the above in the range which does not impair the effect of this invention. Examples of such additives include curable compounds other than the above components and ultraviolet absorbers.

[Method for Producing Light-Emitting Element Forming Resin Composition]
The resin composition for forming a light emitting element is prepared by mixing the polymer (I) and other optional components blended as necessary. Usually, it can be prepared by mixing the polymer (I), a specific solvent, and other components optionally added in a predetermined ratio.

<Resin layer>
The method for producing the resin layer for forming the light emitting device of the present invention is not particularly limited, and the resin composition for forming a light emitting device is directly applied to the second electrode 17 or the like to form a coating film, and then as necessary. The method of removing the specific solvent from the coating film, the resin composition for forming a light emitting element is applied on a support made of polyethylene terephthalate (PET) or the like to form a coating film, and then the coating film is removed from the support. Examples include a method of peeling and laminating on the second electrode 17 or the like.

  Since the resin layer contains the polymer (I), preferably the polymer (II), the refractive index is high. For this reason, for example, when an electrode made of ITO (refractive index of about 2.12) is used as the second electrode 17, the refractive index of the second electrode 17, the resin layer 18, and air decreases in this order. Further, the difference in refractive index between the second electrode 17 and the resin layer 18 and the difference in refractive index between the resin layer 18 and air are small. For this reason, a light emitting element having high light extraction efficiency can be obtained.

  Examples of the method for forming the coating film by applying the resin composition include a roll coating method, a gravure coating method, a spin coating method, a slit coating method, and a method using a doctor blade.

  Although the thickness when apply | coating the said resin composition and forming a coating film is not specifically limited, For example, it is 1-250 micrometers, Preferably it is 2-150 micrometers, More preferably, it is 5-125 micrometers.

  Further, the method for removing the specific solvent from the coating film is not particularly limited, and examples thereof include a method of heating the coating film. By heating the coating film, the organic solvent in the coating film can be evaporated and removed. The heating conditions may be determined as appropriate so long as the organic solvent evaporates, and thermal deformation or modification of various materials due to heat does not occur. For example, the heating temperature is preferably 30 ° C to 300 ° C. It is more preferable that the temperature is from 250C to 250C, and it is more preferable that the temperature is from 50C to 230C.

  Further, the heating time is preferably 10 minutes to 5 hours. Note that heating may be performed in two or more stages. Specifically, after drying at a temperature of 30 to 80 ° C. for 10 minutes to 2 hours, heating is further performed at 100 to 250 ° C. for 10 minutes to 2 hours. Moreover, you may dry in nitrogen atmosphere or pressure reduction as needed.

  The thickness of the resin layer is appropriately selected according to the desired application, but is preferably 20 nm to 100 μm, more preferably 80 nm to 50 μm.

Further, the resin layer preferably has a glass transition temperature (Tg) of 230-350 ° C., preferably 240-330 ° C., measured by Rigaku 8230 DSC measuring device (temperature rising rate 20 ° C./min). Is more preferable, and it is more preferable that it is 250-300 degreeC.
When the resin layer has such a glass transition temperature, heating and heat treatment when forming an electrode or the like on the layer can be performed at a high temperature, so that it has low resistance and high transmittance, and light extraction efficiency. In addition, a light-emitting element having excellent durability can be easily manufactured.

  The resin layer preferably has a tensile strength of 50 to 200 MPa, and more preferably 80 to 150 MPa. The tensile strength can be measured using a tensile tester 5543 (manufactured by INSTRON).

  The resin layer preferably has an elongation at break of 5 to 100%, more preferably 15 to 100%. The elongation at break can be measured using a tensile tester 5543 (manufactured by INSTRON).

  The resin layer preferably has a tensile modulus of 2.5 to 4.0 GPa, and more preferably 2.7 to 3.7 GPa. The tensile elastic modulus can be measured using a tensile tester 5543 (manufactured by INSTRON).

  The resin layer preferably has a linear expansion coefficient of 80 ppm / K or less, more preferably 75 ppm / K or less, measured using an SSC-5200 type TMA measuring device manufactured by Seiko Instruments.

  The resin layer preferably has a humidity expansion coefficient of 15 ppm /% RH or less, and more preferably 12 ppm /% RH or less. The humidity expansion coefficient can be measured using MA (SII Nanotechnology, TMA-SS6100) humidity control option. When the expansion coefficient of the resin layer is within the above range, it indicates that the dimensional stability (environmental reliability) is high, and thus it can be suitably used for a light emitting element.

  The resin layer preferably has a relative dielectric constant of 2.0 to 4.0, more preferably 2.3 to 3.5, and still more preferably 2.5 to 3.2. The relative dielectric constant can be measured using a 4284A type LCR meter manufactured by HP. When the relative dielectric constant is in the above range, the light emitting element including the resin layer tends to exhibit a stable light emitting state.

  When the thickness of the resin layer is 30 μm, the total light transmittance in the JIS K7105 transparency test method is preferably 85% or more, and more preferably 88% or more. Higher total light transmittance is preferable, but sufficient light extraction efficiency can be obtained even if it is 95% or less, and more specifically 90% or less. The total light transmittance can be measured using a haze meter SC-3H (manufactured by Suga Test Instruments Co., Ltd.).

  When the thickness of the resin layer is 30 μm, the light transmittance at a wavelength of 400 nm is preferably 70% or more, more preferably 75% or more, and further preferably 80% or more. The light transmittance at a wavelength of 400 nm can be measured using an ultraviolet / visible spectrophotometer V-570 (manufactured by JASCO).

  When the thickness of the resin layer is 30 μm, the YI value (yellow index) is preferably 3.0 or less, more preferably 2.5 or less, and 2.0 or less. Further preferred. The YI value can be measured using an SM-T color measuring device manufactured by Suga Test Instruments Co., Ltd.

  When the resin layer has a thickness of 30 μm, the YI value after heating for 1 hour at 230 ° C. in the air with a hot air dryer is preferably 3.0 or less, and 2.5 or less. More preferably, it is 2.0 or less.

  The refractive index of the resin layer with respect to light having a wavelength of 633 nm is preferably 1.60 or more, more preferably 1.65 or more, and particularly preferably 1.70 or more. When the refractive index of the resin layer is 1.60 or more, the light extraction efficiency of the obtained light-emitting element is increased. The refractive index can be measured using a prism coupler model 2010 (manufactured by Metricon).

  Since the light-emitting element of the present invention includes the resin layer 18, when light generated in the light-emitting layer 15 passes through the second electrode 17 and enters the air, it is extracted outside the light-emitting element due to light refraction. Efficiency can be increased.

  In FIG. 1, the resin layer 18 is illustrated as being formed in contact with one surface of the second electrode 17, but various layers are further provided between the resin layer 18 and the second electrode 17 as necessary. The side of the substrate 11 opposite to the side where the first electrode 13 is formed, between the substrate 11 and the first electrode 13, between the first electrode 13 and the light emitting layer 15, and between the light emitting layer 15 Various layers may be provided between the first electrode 17 and the second electrode 17 on the opposite side of the resin layer 18 from the side where the second electrode 17 is formed, as necessary. Although not illustrated in FIG. 1, a known sealing layer for sealing the light emitting element 10 may be further provided on the resin layer 18, and various modifications are possible.

FIG. 2 shows a light emitting device 20 which is a second embodiment of the light emitting device of the present invention.
The light emitting element 20 has a structure in which a substrate 21, a resin layer 28, a first electrode 23, a light emitting layer 25, and a second electrode 27 are laminated in this order. That is, the resin layer 28 is provided on the surface of the first electrode 23 opposite to the surface on which the light emitting layer is provided. The first electrode 23 is preferably a transmissive electrode. In this case, light generated in the light emitting layer 25 passes through the first electrode 23, the resin layer 28, and the substrate 21 and is extracted outside the light emitting element 20. sell. The detailed description of each layer constituting the light emitting element 20 and the modification of the light emitting element are the same as described above. In consideration of the light extraction efficiency of the light emitting element 20, the substrate 21 is preferably a transparent plastic substrate having a refractive index smaller than that of the resin layer 28. The resin layer 28 has a high refractive index, and light generated in the light emitting layer 25 can be effectively extracted to the outside by light refraction, so that a light emitting element with high light extraction efficiency is obtained.

FIG. 3 shows a light emitting device 30 which is Embodiment 3 of the light emitting device of the present invention.
The light emitting element 30 has a structure in which a substrate 31, a resin layer 38, a first electrode 33, a light emitting layer 35, a second electrode 37, and a resin layer 39 are laminated in this order. That is, the resin layer 38 is provided on the surface of the first electrode 33 opposite to the surface on which the light emitting layer is provided, and the resin layer 39 is the surface of the second electrode 37 on which the light emitting layer is provided. It is provided on the opposite surface. The first electrode 33 and the second electrode 37 are preferably transmissive electrodes. In this case, the light generated in the light emitting layer 35 passes through the first electrode 33 and the second electrode 37, and then the resin layer 38, respectively. In addition, the light passes through the resin layer 39 and can be taken out of the light emitting element 30. The detailed description of each layer constituting the light emitting element 30 and the modification of the light emitting element are the same as described above. In consideration of the light extraction efficiency of the light emitting element 30, the substrate 31 is preferably a transparent plastic substrate having a refractive index smaller than that of the resin layer 38. The resin layer 38 and the resin layer 39 have a high refractive index, and light generated in the light emitting layer 35 can be effectively extracted to the outside by light refraction, so that a light emitting element with high light extraction efficiency is obtained.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
(1) Structural analysis The structural analysis of the polymers obtained in the following examples and comparative examples was performed by IR (ATR method, FT-IR, 6700 (manufactured by NICOLET)) and NMR (ADVANCE500 type, manufactured by BRUKAAR). It was.

(2) Weight average molecular weight (Mw), number average molecular weight (Mw) and molecular weight distribution (Mw / Mn)
The weight average molecular weight (Mw), number average molecular weight (Mw), and molecular weight distribution (Mw / Mn) of the polymers obtained in the following Examples and Comparative Examples were measured by a TLCOH HLC-8220 GPC apparatus (column: TSKgelα-M). , Developing solvent: THF).

(3) Glass transition temperature (Tg)
The glass transition temperature of the polymer obtained in the following Examples and Comparative Examples or the resin layer for evaluation was measured using a Rigaku 8230 type DSC measuring apparatus at a heating rate of 20 ° C./min.

(3 ') Thermal decomposition temperature The thermal decomposition temperature of the polymers obtained in the following examples and comparative examples was determined by thermogravimetric analysis (TGA: temperature increase rate of 10 ° C / min under nitrogen atmosphere, 5% weight loss temperature). It was measured.

(4) Mechanical strength The tensile strength, breaking elongation, and tensile elastic modulus at room temperature of the evaluation resin layers obtained in the following examples and comparative examples were measured with JIS K7127 using a tensile tester 5543 (manufactured by INSTRON). Measured accordingly.

(5) Environmental stability The linear expansion coefficient of the resin layer for evaluation obtained in the following examples and comparative examples was measured using an SSC-5200 type TMA measuring apparatus manufactured by Seiko Instruments. After the temperature of the obtained evaluation resin layer was raised to Tg minus 20 ° C. once, the linear expansion coefficient was calculated from the gradient of the TMA curve at 200 to 100 ° C. when the temperature was lowered at 3 ° C./min.
The humidity expansion coefficient of the evaluation resin layers obtained in the following examples and comparative examples was measured under the following conditions using MA (SII Nanotechnology, TMA-SS6100) humidity control option.
Humidity condition: humidified from 40% RH to 70% RH (tensile method: weight 5 g) Temperature: 23 ° C.

(6) Relative permittivity Using a 4284A type LCR meter manufactured by HP, the relative permittivity of the evaluation resin layers obtained in the following examples and comparative examples was measured. Measurement conditions are as follows. Frequency: 100 MHz, atmosphere: room temperature in the atmosphere, electrode: electrode on which aluminum with a diameter of 5 mm is deposited (with guard electrode)

(7) Water Absorption Three evaluation resin layers obtained in the following Examples and Comparative Examples were cut out to a size of 3 cm × 4 cm and dried at 180 ° C. under reduced pressure for 8 hours. After measuring the mass of the resin layer after drying, it was immersed in distilled water at 25 ° C. for 24 hours. After immersion, water droplets on the surface of the resin layer were wiped off, the water absorption was calculated from the mass change before and after immersion, and the average value of the three sheets was calculated.

(8) Optical properties With respect to the resin layers for evaluation obtained in the following examples and comparative examples, the total light transmittance and the yellow index (YI value) were measured according to the JIS K7105 transparency test method. Specifically, the total light transmittance was measured using a haze meter SC-3H manufactured by Suga Test Instruments Co., Ltd., and the YI value was measured using a SM-T color meter manufactured by Suga Test Instruments Co., Ltd. (heating) Previous YI).
In addition, after the evaluation resin layers obtained in the following Examples and Comparative Examples were heated in the air at 230 ° C. for 1 hour in a hot air dryer, the YI value was measured by SM-T type color measurement manufactured by Suga Test Instruments Co., Ltd. Measured using a vessel (YI after heating). The measurement was performed according to JIS K7105 conditions.

  The light transmittance at a wavelength of 400 nm of the evaluation resin layers obtained in Examples and Comparative Examples was measured using an ultraviolet / visible spectrophotometer V-570 (manufactured by JASCO), and the evaluation resin layers thus obtained were used. The refractive index was measured using a prism coupler model 2010 (manufactured by Metricon). The refractive index was measured using a wavelength of 633 nm.

(9) Film-formability of resin layer for light-emitting element A resin composition obtained in Examples and Comparative Examples is dispensed on a 4-inch diameter fused quartz or silicon substrate and spin-coated so as to have a thickness of about 1 μm. And then dried at 70 ° C. for 30 minutes, then heated at 150 ° C. for 10 minutes, and further dried at 230 ° C. for 2 hours to produce a resin layer for light emitting element (film thickness: 1 μm). The resin layer was visually examined for the presence of repellency, foaming (surface irregularities), and discoloration. Those with no repellency, foaming, or discoloration were marked with “◯”, those with a partial appearance of “△”, and those with the entire surface appearing with “X”. The “repellency” was evaluated by visually observing the presence or absence of interference unevenness on the surface of the resin layer as an appearance.

[Example 1]
<Synthesis of polymer>
In a 3 L four-necked flask, component (A): 35.12 g (0.253 mol) of 2,6-difluorobenzonitrile (hereinafter also referred to as “DFBN”), component (B): 9,9-bis (4- Hydroxyphenyl) fluorene (hereinafter also referred to as “BPFL”) 70.08 g (0.200 mol), resorcinol (hereinafter also referred to as “RES”) 5.51 g (0.050 mol), potassium carbonate 41.46 g (0.300 mol) ), 443 g of N, N-dimethylacetamide (hereinafter also referred to as “DMAc”) and 111 g of toluene were added. Subsequently, a thermometer, a stirrer, a three-way cock with a nitrogen introduction tube, a Dean-Stark tube and a cooling tube were attached to the four-necked flask.

Next, after the atmosphere in the flask was replaced with nitrogen, the obtained solution was reacted at 140 ° C. for 3 hours, and water produced was removed from the Dean-Stark tube as needed. When no more water was observed, the temperature was gradually raised to 160 ° C. and reacted at that temperature for 6 hours.
After cooling to room temperature (25 ° C.), the produced salt was removed with a filter paper, the filtrate was poured into methanol for reprecipitation, and the filtrate (residue) was isolated by filtration. The obtained filtrate was vacuum dried at 60 ° C. overnight to obtain a white powder (polymer) (yield 95.67 g, yield 95%).

Table 1 shows the physical properties of the obtained polymer. The obtained polymer was subjected to structural analysis and measurement of the weight average molecular weight. The results show that the characteristic absorption of the infrared absorption spectrum is 3035 cm ⁻¹ (C—H stretching), 2229 cm ⁻¹ (CN), 1574 cm ⁻¹ , 1499 cm ⁻¹ (aromatic ring skeleton absorption), 1240 cm ⁻¹ (—O—). And the weight average molecular weight was 130,000. The obtained polymer had the structural units (1) and (3).

Next, the obtained polymer was redissolved in DMAc to obtain a resin composition having a polymer concentration of 20% by mass. The resin composition was applied onto a support made of polyethylene terephthalate (PET) using a doctor blade, dried at 70 ° C. for 30 minutes, and then dried at 100 ° C. for 30 minutes to obtain a coating film. It peeled from the PET support. Thereafter, the coating film was fixed to a metal frame and further dried at 230 ° C. for 2 hours to obtain an evaluation resin layer having a thickness of 30 μm. Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light-emitting element resin layer.
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Example 2]
The same procedure as in Example 1 was performed except that 11.41 g (0.050 mol) of 2,2-bis (4-hydroxyphenyl) propane was used instead of RES. Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light-emitting element resin layer.
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Example 3]
As component (B), instead of 70.08 g of BPFL and 5.51 g of RES, 78.84 g (0.225 mol) of BPFL and 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3- The same operation as in Example 1 was carried out except that 8.41 g (0.025 mol) of hexafluoropropane was used. Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light-emitting element resin layer.
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Example 4]
Example 1 except that 125.65 g (0.250 mol) of 9,9-bis (3-phenyl-4-hydroxyphenyl) fluorene was used as the component (B) instead of 70.08 g of BPFL and 5.51 g of RES. The same was done. Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light-emitting element resin layer.
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Example 5]
(B) It carried out similarly to Example 1 except having used BPFL87.60g (0.250mol) instead of BPFL70.08g and RES5.51g. Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light-emitting element resin layer.
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Example 6]
(B) Instead of using 70.08 g of BPFL and 5.51 g of RES, 78.84 g (0.225 mol) of BPFL and 6.71 g (0.025 mol) of 1,1-bis (4-hydroxyphenyl) cyclohexane were used. Was performed in the same manner as in Example 1. Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light-emitting element resin layer.
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Example 7]
(A) It carried out similarly to Example 5 except having used DFBN28.10g (0.202 mol) and 4,4'- difluoro benzophenone 11.02g (0.051 mol) instead of DFBN35.12g. . Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light-emitting element resin layer.
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Example 8]
(A) It carried out similarly to Example 7 except having changed the compounding quantity of the component into DFBN 17.56g (0.126mol) and 4,4'- difluoro benzophenone 27.55g (0.126mol). Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light emitting element resin layer.
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Example 9]
The same procedure as in Example 5 was performed except that 78.84 g (0.250 mol) of 4,4′-difluorodiphenylsulfone (DFDS) was used as the component (A) instead of 35.12 g of DFBN. Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light-emitting element resin layer.
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Example 10]
A solution obtained by re-dissolving the polymer obtained in Example 1 in DMAc to a polymer concentration of 20% by mass was added to a bead mill container, and then zirconium oxide (primary average particle diameter: 15 nm) was added to the obtained solution. ) In an amount of 80 parts by mass with respect to 100 parts by mass of the polymer, 350 parts by mass of zirconia beads having a particle size of 0.1 mm (manufactured by Nikkato), and 1500 rpm for 10 hours using a bead mill. After stirring, the fine particles of zirconium oxide were dispersed, and then the zirconia beads were removed to obtain a resin composition. It carried out similarly to Example 1 except having used this resin composition. Table 1 shows the results of film formability of the evaluation resin layer and the light-emitting element resin layer.

For the fine particles in the obtained resin composition, the volume average particle diameter at 25 ° C. was measured by a dynamic light scattering particle size distribution analyzer manufactured by Horiba, Ltd., and the volume average particle diameter was less than 50 nm. .
The obtained resin layer (resin layer for light-emitting element) has a high refractive index and is excellent in heat resistance (high Tg), film formability, environmental stability, and the like. Excellent efficiency and durability.

[Comparative Example 1]
As component (B), instead of 70.08 g of BPFL and 5.51 g of RES, 84.06 g of 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane (0. 250 mol) was used in the same manner as in Example 1. Table 1 shows the results of film formability of the obtained polymer, the evaluation resin layer, and the light-emitting element resin layer.

10, 20, 30 Light emitting element 11, 21, 31 Substrate 13, 23, 33 First electrode 15, 25, 35 Light emitting layer 17, 27, 37 Second electrode 18, 28, 38, 39 Resin layer

Claims (7)

A light emitting device comprising a substrate, a first electrode, a light emitting layer, a second electrode, and a resin layer,
The substrate, the first electrode, the light emitting layer, and the second electrode are laminated in this order,
The resin layer is
(A) a side of the first electrode opposite to the side on which the light emitting layer is formed; and
(B) The side of the second electrode opposite to the side on which the light emitting layer is formed,
Formed on at least one of
The resin layer is, Ri layer der including differential scanning calorimetry (DSC, heating rate 20 ° C. / min) by the glass transition temperature (Tg) of which is the 230 to 350 ° C. aromatic polyether polymer, and the humidity expansion emitting element coefficients characterized by the following der Rukoto RH 15 ppm /%.   The light emitting device according to claim 1, wherein the light emitting device is an organic electroluminescence device. The aromatic polyether polymer has at least one structural unit (i) selected from the group consisting of a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2). 3. The light emitting device according to 1 or 2.

(In Formula (1), R < ¹ > -R < ⁴ > shows a C1-C12 monovalent organic group each independently, and ad shows the integer of 0-4 each independently.)

(In Formula (2), R < ¹ > -R < ⁴ > and ad are respectively synonymous with R < ¹ > -R < ⁴ > and said ad in said Formula (1), Y is a single bond, -SO _2- or> C = O, R ⁷ and R ⁸ each independently represent a halogen atom, a monovalent organic group having 1 to 12 carbon atoms or a nitro group, and g and h each independently represent 0 to 4 represents an integer of 4 and m represents 0 or 1. However, when m is 0, R ⁷ is not a cyano group. The aromatic polyether polymer further has at least one structural unit (ii) selected from the group consisting of a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4). The light emitting device according to claim 3 .

(In formula (3), R ⁵ and R ⁶ each independently represent a monovalent organic group having 1 to 12 carbon atoms, and Z represents a single bond, —O—, —S—, —SO ₂ —, > C═O, —CONH—, —COO— or a divalent organic group having 1 to 12 carbon atoms, e and f each independently represent an integer of 0 to 4, and n represents 0 or 1 .)

(In the formula ^{(4), R 7, R} 8, Y, m, g and h are each R ⁷ in independent to the formula ^{(2), R 8, Y} , m, synonymous with g and h, R ^5, R ^6, Z, n, e and f are as defined each R ⁵ in the formula (3) independently, R ^6, Z, n, e and f.) The light emitting element of Claim 4 whose molar ratio of the said structural unit (i) and the said structural unit (ii) is 50: 50-100: 0 in the said aromatic polyether type polymer.   The light emitting device according to any one of claims 1 to 5, wherein the weight average molecular weight in terms of polystyrene by gel permeation chromatography (GPC) of the aromatic polyether polymer is 5,000 to 500,000. .   The light emitting element according to claim 1, wherein the resin layer further contains metal oxide particles.

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