JP2018178061A - Wavelength conversion composition and light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wavelength conversion composition exhibiting high quantum yield and excellent durability, and further having performance to convert an incident light to an ejection light with a targeted wavelength, and a light-emitting device using the wavelength conversion composition.SOLUTION: There are provided a wavelength conversion composition converting an incident light to a light with long wavelength and containing a photoluminescence phosphor and a binder resin, in which at least one of the photoluminescence phosphor is a compound represented by a specific general formula (I), the binder resin is a silicone resin or an epoxy resin, and a light-emitting device having a light source, and a wavelength conversion part for converting a light emitted by the light source, consisting of the wavelength conversion composition.SELECTED DRAWING: None

Description

  The present invention relates to a wavelength conversion composition and a light emitting device.

In recent years, development of devices using optoelectronics or photoelectronics has been rapidly developed, and, for example, light emitting elements such as organic light emitting diodes (OLEDs) and inorganic light emitting diodes, and wavelength conversion elements are put to practical use. With the development or application expansion of these devices, research and development of luminescent compounds used for the devices or compositions containing the luminescent compounds are also actively promoted.
For example, as a light emitting compound or composition used in a light emitting layer of an OLED, Non Patent Literature 1 discloses a composition (a film obtained by dissolving 1,4-bis (diallylamino) -2,5-diethenylbenzene in polystyrene) ) Is described. Patent Document 1 also describes, for example, 2,5-bis ((2E) -2-ethoxycarbonylethenyl) -1,4-bis (dipiperidinobenzene).
Patent Document 2 describes a wavelength conversion material in which a perylene compound is dissolved in a specific polyester as a light emitting compound or a composition used for a wavelength conversion element. Patent Document 3 describes a color conversion composition in which a pyrromethene boron complex compound is dissolved in a binder resin.
Furthermore, Non Patent Literature 2 describes 1,4-bis (diallylamino) -2,5-bis (phenylethenyl) benzene as a compound that can be used for biological imaging applications.

By the way, light emitting diodes that emit white light are widely used in display devices such as various displays. Further, in recent years, there has been a growing interest in problems related to energy saving, and those using white LEDs as lighting devices such as fluorescent lamps are rapidly spreading.
White LEDs are usually constructed by combining LEDs and phosphors. This phosphor absorbs the light of a specific wavelength (incident light) emitted from the LED, and emits a light of a specific wavelength (outgoing light) different from this light. It is formed from the wavelength conversion composition containing light emitting compound and resin. Among the photoluminescent phosphors, organic photoluminescent phosphors have an advantage over inorganic photoluminescent phosphors in that they exhibit high wavelength conversion efficiency. Examples of such organic photoluminescent phosphors include the compounds described in Patent Documents 2 and 3 above. In addition, there is no description regarding using the luminescent compound as described in patent document 1 and nonpatent literature 1 and 2 as fluorescent substance of LED.

International Publication No. 2010/047335 Japanese Patent Application Publication No. 2013-542595 International Publication No. 2016/190283

Angew. Chem. Int. Ed. 2012, 51, 4095-4099 Angew. Chem. Int. Ed. 2016, 55, 155-159

As described in Patent Documents 2 and 3, conventional wavelength conversion compositions containing organic photoluminescent phosphors are mainly those in which photoluminescent phosphors are dissolved in resin . By dissolving the phosphor in the resin, it is possible to increase the light extraction efficiency from the wavelength conversion composition by utilizing the high transparency of the wavelength conversion composition. In addition, in a light emitting device using a wavelength conversion composition, the quantum yield generally decreases due to aggregation-induced quenching when the photoluminescent phosphor is in an aggregation state or a solid state. Therefore, by dissolving the photoluminescent phosphor in the resin, aggregation of the photoluminescent phosphor can be suppressed, and the decrease in quantum yield can also be suppressed.
However, the quantum yield exhibited by the conventional wavelength conversion composition is not sufficient even by utilizing the high transparency of the wavelength conversion composition. In particular, wavelength conversion compositions that convert incident light into red light (light of wavelength 580 to 750 nm) have a low quantum yield. Even when the wavelength conversion material and the color conversion composition described in Patent Documents 2 and 3 are used, a sufficient quantum yield can not be obtained, and there is room for improvement. In the present invention, the quantum yield refers to the ratio of the number of photons emitted as fluorescence to the number of photons absorbed by the photoluminescent phosphor.

In addition, organic photoluminescent phosphors, in particular, wavelength conversion compositions in which organic photoluminescent phosphors are dissolved in a resin are generally not sufficiently durable (to light or heat), and their use Low durability is compensated by the form etc. As a method of compensating for the low durability of the wavelength conversion composition, for example, as described in Patent Document 2, in the case of applying to a light emitting device, a wavelength conversion portion or a wavelength conversion portion made of the wavelength conversion composition There has been proposed a method of providing the light source at a position away from the light source.
However, the durability required for the wavelength conversion composition and the like is high, and the photoluminescence exhibiting sufficient durability even when provided at a position close to the light source due to the demand for downsizing of the light emitting device, etc. Phosphors or wavelength conversion compositions are desired.

By the way, it is important for the wavelength conversion composition to maintain the function or the property of converting the incident light into the outgoing light of the specific wavelength (the aggregation / association emission wavelength of the photoluminescent phosphor) for the purpose. However, when an organic photoluminescent phosphor is dissolved in a resin, in general, the wavelength of emission light wavelength-converted by the wavelength conversion composition changes to a wavelength different from the target wavelength. That is, it becomes impossible to convert the incident light into the outgoing light of the specific wavelength for the purpose.
As mentioned above, it is important not to aggregate photoluminescent phosphors in terms of achieving high quantum yield. However, it is difficult to completely dissolve the photoluminescent phosphor at a high concentration in a commonly used resin. That is, the insoluble matter of the photoluminescent phosphor coexists in the mixture of the photoluminescent phosphor and the resin. If the insolubles coexist, the incident light can not be converted into the outgoing light of the specific wavelength for the purpose. On the other hand, as described above, the photoluminescent phosphor is present (contained) in the resin without being dissolved in the resin, in that the incident light is controlled to be converted only to the emitted light of the specific wavelength. Wavelength conversion compositions are desired.

  The present invention exhibits a high quantum yield and excellent durability, and further has a wavelength conversion composition (also referred to as a wavelength conversion material) having the ability to convert incident light into outgoing light of a target wavelength. An object of the present invention is to provide a light emitting device using this wavelength conversion composition.

  The present inventor uses the compound represented by the specific general formula (I) described later as a photoluminescent phosphor (luminescent compound) in combination with a silicone resin or an epoxy resin to obtain a photoluminescent phosphor as described above. It has been found that it is possible to prepare a wavelength conversion composition dispersed in solid state in a resin. In addition, it has been found that the wavelength conversion composition for achieving the dispersion state exhibits a high quantum yield and is excellent in durability, and can be suitably used as a wavelength conversion material in a light emitting device such as a white LED. The present invention has been further studied based on these findings and has been completed.

式中、Ａｒ^１及びＡｒ^２は各々独立にアリール基又はヘテロアリール基を示し、Ｒ^１及びＲ^２は各々独立にアルキル基、アルキルカルボニル基、アルケニルカルボニル基、アリール基又はヘテロアリール基を示す。Ｒ^３、Ｒ^４、Ｒ^６及びＲ^７は各々独立に水素原子、アルキル基、アリール基、ヘテロアリール基、電子求引性基、又は電子求引性基が置換したアリール基を示す。ただし、Ｒ^３、Ｒ^４、Ｒ^６及びＲ^７のいずれか１つは電子求引性基、又は電子求引性基が置換したアリール基である。Ｒ^５及びＲ^８は各々独立に水素原子、アルキル基又はアリール基を示す。 That is, the object of the present invention is achieved by the following means.
It is a wavelength conversion composition containing photoluminescence fluorescent substance and binder resin which converts the wavelength of <1> incident light into light of a longer wavelength,
The wavelength conversion composition whose at least 1 sort (s) of photoluminescent fluorescent substance is a compound represented by following General formula (I), and whose binder resin is a silicone resin or an epoxy resin.

In the formula, Ar ¹ and Ar ² each independently represent an aryl group or a heteroaryl group, and R ¹ and R ² each independently represent an alkyl group, an alkylcarbonyl group, an alkenylcarbonyl group, an aryl group or a heteroaryl group. R ³ , R ⁴ , R ⁶ and R ⁷ each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, an electron withdrawing group, or an aryl group substituted with an electron withdrawing group. However, any one of R ³ , R ⁴ , R ⁶ and R ⁷ is an electron withdrawing group or an aryl group substituted by the electron withdrawing group. R ⁵ and R ⁸ each independently represent a hydrogen atom, an alkyl group or an aryl group.

The light-emitting device provided with the <2> light source and the wavelength conversion part which consists of a wavelength conversion composition as described in <1> which converts the light light-emitted by this light source.
<3> ^R 3 in the general formula ^(I), R 4, electron-withdrawing groups can take as ^{R 6} and ^{R 7,} the light emitting device according to a cyano group, an alkoxycarbonyl group or a sulfo group <2>.
<4> At least two of R ³ , R ⁴ , R ⁶ and R ^{7 in} the general formula (I) are a cyano group, an alkoxycarbonyl group, a sulfo group, or an aryl group substituted with an electron-withdrawing group The light-emitting device as described in 2> or <3>.
<5> ^{R 5} and ^{R 8} in the general formula (I) are both a hydrogen atom <2> - emitting device according to any one of <4>.
Any one of <2> to <5> in which R ⁴ and R ⁷ in the <6> general formula (I) are both an aryl group, a heteroaryl group or an aryl group substituted with an electron-withdrawing group The light emitting device according to claim 1.
<7> ^{R 1} and ^{R 2} in the general formula (I) are both an aryl or heteroaryl group <2> - emitting device according to any one of <6>.
<8> ^{R 3} and ^{R 6} in the general formula (I) are both a cyano group or an alkoxycarbonyl group <2> - emitting device according to any one of <7>.
The light-emitting device as described in any one of <2>-<8> in which a <9> light source light-emits wavelength light of 350 nm or more and 480 nm or less.
The compound represented by <10> general formula (I) absorbs light emitted from a light source and exhibits light emission in which a peak wavelength is observed in a range of 580 nm to 750 nm. The light emitting device according to any one of the preceding claims.

  The wavelength conversion composition of the present invention exhibits high quantum yield and excellent durability, and when used in a wavelength conversion portion, red light obtained by wavelength-converting incident light with high quantum yield over a long period of time It can emit light. In addition, the light emitting device of the present invention exhibits high quantum yield and excellent durability.

In the present specification, unless otherwise specified, the double bond may be either E-type or Z-type in the molecule, or a mixture thereof.
When there are a plurality of substituents, linking groups, ligands and the like (hereinafter referred to as substituents and the like) represented by a specific code or formula, or when a plurality of substituents and the like are simultaneously defined, no particular notice As long as it is, each substituent etc. may mutually be same or different. The same applies to the definition of the number of substituents and the like. In addition, when a plurality of substituents and the like are adjacent (especially, adjacent), they may be linked to each other to form a ring unless otherwise specified. In addition, unless otherwise specified, the ring, for example, an alicyclic ring, an aromatic ring or a hetero ring may be further condensed to form a condensed ring.

  In the present specification, the expression of a compound (including a complex and a dye) is used to mean including the salt thereof and the ion thereof as well as the compound itself. Moreover, it is a meaning including what changed a part of structure in the range which does not impair the effect of this invention. Furthermore, the compound which does not specify substitution or non-substitution is the meaning which may have arbitrary substituents in the range which does not impair the effect of this invention. The same applies to substituents, linking groups and ligands.

  Moreover, the numerical range represented using "-" in this specification means the range which includes the numerical value described before and after "-" as a lower limit and an upper limit.

[Wavelength conversion composition]
The wavelength conversion composition of the present invention contains a photoluminescent phosphor and a binder resin. The wavelength converting composition converts the wavelength of incident light to light of a longer wavelength. Specifically, incident light (for example, light with a wavelength of 350 nm or more and 480 nm or less) can be converted into emitted light with a target wavelength (for example, 580 nm or more and 750 nm or less).
The photoluminescent phosphor means a phosphor that converts the wavelength of incident light into light having a longer wavelength, and is also referred to as a wavelength conversion material. The incident light in the photoluminescent phosphor and the long wavelength light obtained by converting the incident light are the same as the above-described wavelength conversion composition. In the wavelength conversion composition of the present invention, the photoluminescent phosphor may contain one kind alone or two or more kinds, but at least one kind of a compound represented by the following general formula (I) , And may be referred to as Compound (I). In the wavelength conversion composition, the compound (I) is dispersed in a solid state in a binder resin described later.
In the present invention, the fact that compound (I) is dispersed in the binder resin in a solid state means that compound (I) is dispersed in the binder resin without dissolution, compatibility or elution (solid dispersion or Solid composition). Here, the solid state includes, in addition to the embodiment in which the compound (I) is completely in the solid state, an embodiment in which a part of the compound (I) is not in the solid state as long as the target wavelength conversion function is not impaired. Do. The range in which the target wavelength conversion function is not impaired can not be uniquely determined in accordance with the properties or the use of the compound (I). For example, when it comes to the wavelength of light whose wavelength is converted by the wavelength conversion composition, the wavelength is shortened or lengthened by about 30 nm with respect to the wavelength of emitted light (the aggregation / association emission wavelength of compound (I)) There is a range. In the case where the compound (I) is colored, a range in which the binder resin in the wavelength conversion composition (wavelength conversion portion) is not colored in a color different from that exhibited by itself when checked visually . Furthermore, in place of the method of shortening the wavelength or increasing the wavelength or coloring, the range defined by the evaluation method by the fluorescence spectrum in the examples described later can also be used.
Further, in the present invention, the composition means a component concentration within the range not impairing the target wavelength conversion function described above in addition to the mixture in which the component concentration is constant (each component is uniformly dispersed). Includes fluctuating mixtures.

<Compound Represented by General Formula (I)>
The compound (I) contained in the wavelength conversion composition of the present invention is represented by the following general formula (I).

In the general formula (I), Ar ¹ and Ar ² each independently represent an aryl group or a heteroaryl group, preferably an aryl group. Ar ¹ and Ar ² may be the same or different, and may have a substituent. The substituent which Ar ¹ or Ar ² may have is not particularly limited, but is preferably selected from Substituent Group T described later. Particularly preferred is an alkyl group or a hydroxyl group.

The aryl group that can be taken as Ar ¹ and Ar ² is not particularly limited, and may be a monocyclic group or a condensed ring group (preferably, a condensed ring group of 2 to 6 rings). The number of carbon atoms in the aryl group is preferably 6 to 48, more preferably 6 to 24 carbons, still more preferably 6 to 14 carbons, and particularly preferably 6 to 10. Examples of the aryl group include benzene ring group, naphthalene ring group, fluorene ring group, anthracene ring group, phenanthrene ring group, chrysene ring group or pyrene ring group, and benzene ring group or naphthalene ring group is preferable, and benzene ring is preferable. Groups are more preferred.

The heteroaryl group that can be taken as Ar ¹ and Ar ² is not particularly limited, but preferably contains at least one of a nitrogen atom, an oxygen atom, a sulfur atom, a phosphorus atom, a silicon atom or a selenium atom as a ring constituting hetero atom . The heteroaryl group may be a single ring group or a condensed ring group (preferably a 2 to 6 ring condensed ring group). When it is a single ring group, the number of ring members is preferably 5 to 7 members, more preferably 5 members or 6 members. The carbon number of the heteroaryl group is not particularly limited, but is preferably 0 to 22, more preferably 0 to 10, and still more preferably 1 to 6.

In General Formula (I), R ¹ and R ² each independently represent an alkyl group, an alkylcarbonyl group, an alkenylcarbonyl group, an aryl group or a heteroaryl group. Each of R ¹ and R ² is preferably an alkyl group, an aryl group or a heteroaryl group, more preferably an aryl group or a heteroaryl group, still more preferably an aryl group. R ¹ and R ² may be the same or different, and may have a substituent. The substituent which R ¹ or R ² may have is not particularly limited, but is preferably selected from the substituent group T described later.

The alkyl group which can be taken as R ¹ and R ² includes a linear alkyl group, a branched alkyl group or a cyclic alkyl group, a linear alkyl group or a branched alkyl group is preferable, and a linear alkyl group is preferable. The carbon number of the linear alkyl group or the branched alkyl group is preferably 1 to 36, more preferably 1 to 18, still more preferably 1 to 12, and particularly preferably 1 to 6. The carbon number of the cyclic alkyl group is preferably 3 to 20, more preferably 3 to 12, and further preferably 3 to 8.

The alkylcarbonyl group that can be taken as R ¹ and R ² is not particularly limited, and a group formed by combining an alkyl group that can be taken as R ¹ and R ² and a carbonyl group is preferable.
The alkenylcarbonyl group that can be taken as R ¹ and R ² is preferably a group formed by combining an alkenyl group and a carbonyl group. The alkenyl moiety in the alkenylcarbonyl group includes a linear alkenyl group, a branched alkenyl group or a cyclic alkenyl group, a linear alkenyl group or a branched alkenyl group is preferable, and a linear alkenyl group is preferable. The carbon number of the linear alkenyl group or branched alkenyl group is preferably 2 to 36, more preferably 2 to 18, still more preferably 2 to 12, and particularly preferably 2 to 6. The carbon number of the cyclic alkenyl group is preferably 3 to 20, more preferably 3 to 12, and still more preferably 3 to 8.

The aryl group and heteroaryl group which can be taken as R ¹ and R ² have the same meanings as the aryl group and heteroaryl group which can be taken as Ar ¹ and Ar ² respectively, and the preferred ranges are also the same.

In General Formula (I), the combination of Ar ¹ and R ¹ and the combination of Ar ² and R ² are not particularly limited. Preferably, it is a combination of the above preferable group that can be taken as Ar ¹ and Ar ² and the above preferable group that can be taken as R ¹ and R ² , and in each combination, more preferably both are an aryl group, more preferably both It is a benzene ring group. The combination of Ar ¹ and R ¹ and the combination of Ar ² and R ² may be identical or different, and are preferably identical.

Ar ¹ and R ¹ , and Ar ² and R ² may respectively form a ring via a single bond or a linking group. The linking group is not particularly limited, and includes divalent groups. The divalent group is not particularly limited, and examples thereof include an alkylene group, an alkenylene group, an alkynylene group, an arylene group, a heteroarylene group, a carbonyl group, an ether group or a thioether group, and an alkylene group or a carbonyl group is preferable. The carbon number of the alkylene group, the arylene group and the heteroarylene group is not particularly limited, but is preferably the same as each group which can be taken as Ar ¹ or R ¹ . The carbon number of the alkenylene group and the alkynylene group is preferably the same as the alkenylene group in the alkenylcarbonyl group which can be taken as R ¹ .

In the general formula (I), each of R ³ , R ⁴ , R ⁶ and R ⁷ independently represents a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, an electron withdrawing group, or an electron withdrawing group A substituted aryl group (hereinafter sometimes referred to as an electron-withdrawing group-substituted aryl group) is shown. Among them, an aryl group, an electron withdrawing group or an electron withdrawing group substituted aryl group is preferable. R ³ , R ⁴ , R ⁶ and R ⁷ may be the same as or different from each other, and R ³ and R ⁶ and R ⁴ and R ⁷ may also be the same as each other It may be different.
The alkyl group, aryl group and heteroaryl group which can be taken as R ³ , R ⁴ , R ⁶ and R ⁷ are, respectively, an alkyl group which can be taken as R ¹ and R ² , an aryl group and which can be taken as Ar ¹ and Ar ² respectively. Preferred is the same as the aryl group.

In the present invention, the electron withdrawing group is a substituent having an electron withdrawing property by the electron effect, and the substituent constant σp of Hammett's rule, which is a measure of the electron withdrawing property of the substituent and the electron donating property. Means a substituent having a σp value of 0 or more.
In the present invention, the σp values of substituents are as described in Corwin Hansch, A., et al. LEO and R. W. TAFT, "A Survey of Hammett Substituents and Resonances and Field Parameters", Chem. Rev. , 91, 165-195 (1991).

The electron withdrawing group that can be taken as R ³ , R ⁴ , R ⁶ and R ⁷ may be a substituent having the above-mentioned σp value, and the σp value is preferably 0.05 or more, more preferably 0. 10 or more. The upper limit of the σp value is not particularly limited, but is practically 1 or less.
Specifically as an electron withdrawing group, each group of a cyano group, the alkoxy carbonyl group, the aryloxy carbonyl group, and a sulfo group is mentioned, for example. Among them, a cyano group, an alkoxycarbonyl group or a sulfo group is preferable.

The alkyl group in the alkoxycarbonyl group and the aryl group in the aryloxycarbonyl group are not particularly limited, but are each an alkyl group that can be taken as R ¹ and R ² , or an aryl group that can be taken as Ar ¹ and Ar ^{2 respectively} And preferred ones are also the same.

The aryl group in the electron-withdrawing group-substituted aryl group is not particularly limited, but is the same as the aryl group that can be taken as Ar ¹ and Ar ² , and preferable ones are also the same. The electron-withdrawing group that the electron-withdrawing group substituted aryl group has is not particularly limited as long as it satisfies the above-mentioned σp value, and the above-mentioned electron-withdrawing group can be mentioned. Among them, the electron-withdrawing group possessed by the electron-withdrawing group substituted aryl group is preferably a halogen atom (preferably a fluorine atom or a chlorine atom), a cyano group or a fluorinated alkyl group (preferably a perfluoroalkyl group). The alkyl group (before being fluorinated) in the fluorinated alkyl group is not particularly limited, but is the same as the alkyl group which can be taken as R ¹ and R ² respectively, and preferable ones are also the same. The number of electron withdrawing groups which the electron withdrawing group substituted aryl group has may be one or more, preferably 1 to 4 and more preferably 1 to 3. The substitution position of the aryl group to be substituted by the electron-withdrawing group is not particularly limited, but when the aryl group is a benzene ring, for example, 2 is substituted for the bonding position with sp ² carbon atom in General Formula (I) The position (adjacent position) may be any of 3-position or 4-position, preferably 2-position or 4-position, and particularly preferably 4-position.

In the general formula (I), at least one of R ³ , R ⁴ , R ⁶ and R ⁷ takes an electron withdrawing group or an electron withdrawing group substituted aryl group. Thereby, durability can be further improved. The number of the electron withdrawing group or the electron withdrawing group-substituted aryl group among R ³ , R ⁴ , R ⁶ and R ⁷ may be one or more, preferably two or four. .
When at least two of R ³ , R ⁴ , R ⁶ and R ⁷ adopt an electron withdrawing group or an electron withdrawing group-substituted aryl group, the two electron withdrawing groups are a cyano group, an alkoxycarbonyl group, A sulfo group or an electron withdrawing group substituted aryl group is preferred.
Among R ³ , R ⁴ , R ⁶ and R ⁷ , any one having an electron withdrawing group may be used, but R ³ and R ⁶ are electron withdrawing groups (in the general formula (I) The benzene ring and the electron withdrawing group are preferably in the Z configuration in the ethylene bond. In particular, when both R ³ and R ⁶ adopt an electron withdrawing group, the electron withdrawing group is preferably a cyano group or an alkoxycarbonyl group.
Each of R ⁴ and R ⁷ is preferably an aryl group, a heteroaryl group or an electron withdrawing group substituted aryl group, more preferably an aryl group or an electron withdrawing group substituted aryl group, aryl More preferably, it is a group.

In general formula (I), R ⁵ and R ⁸ are each independently a hydrogen atom, an alkyl group or an aryl group, a hydrogen atom is preferable. The alkyl group and aryl group which can be taken as R ⁵ and R ^{8 are the same} as the alkyl group which can be taken as R ¹ and R ² , or the aryl group which can be taken as Ar ¹ and Ar ^{2 respectively} , and the preferred range is also the same. is there.
The ethenylene group having R ^{3 to} R ⁵ and the ethenylene group having R ^{6 to} R ⁸ may be the same as or different from each other, and are preferably the same.

Each of R ^{3 to} R ⁸ may have a substituent. The R ³ to R ⁸ are substituents which may have, but are not limited to, preferably, selected from substituent group T described below. However, when R ³ , R ⁴ , R ⁶ and R ⁷ are aryl groups, the substituent which they may have is a group other than an electron-withdrawing group.

-Substituent group T-
In the present invention, preferable substituents include substituents selected from the following Substituent Group T.
Further, in the present specification, when only described as a substituent, this substituent group T is referred to, and when each group, for example, an alkyl group is only described, The preferred range in the corresponding group of this substituent group T is applied.
Furthermore, in the present specification, when an alkyl group is described as being distinguished from a cyclic (cyclo) alkyl group, the alkyl group is used to include a linear alkyl group and a branched alkyl group. On the other hand, when an alkyl group is not described as being distinguished from a cyclic alkyl group (in the case where it is simply described as an alkyl group), and unless otherwise specified, the alkyl group is a linear alkyl group or a branched alkyl group And cycloalkyl groups are used in the meaning. The same applies to a group containing a group capable of adopting a cyclic structure (alkyl group, alkenyl group, alkynyl group, etc.) (alkoxy, alkylthio group, alkenyloxy group etc.), and a compound containing a group capable of cyclic structure. is there. When the group can form a cyclic skeleton, the lower limit of the number of atoms of the group forming the cyclic skeleton is 3 or more regardless of the lower limit of the number of atoms specifically described below for the group capable of adopting this structure, Five or more are preferable.
In the following description of Substituent Group T, for example, in order to clarify a linear or branched group and a cyclic group, such as an alkyl group and a cycloalkyl group, they are separately described. There is also.

Groups included in Substituent Group T include the following groups.
Alkyl group (preferably having a carbon number of 1 to 20, more preferably 1 to 12, still more preferably 1 to 6), alkenyl group (preferably having a carbon number of 2 to 20, more preferably 2 to 12), an alkynyl group (preferably having a Carbon number 2 to 20, more preferably 2 to 12), cycloalkyl group (preferably carbon number 3 to 20), cycloalkenyl group (preferably carbon number 5 to 20), aryl group (preferably carbon number 6 to 26) And more preferably 6 to 10), a heterocyclic group (having at least one oxygen atom, sulfur atom or nitrogen atom as a ring-constituting atom, preferably having a carbon number of 2 to 20. 5- or 6-membered ring Heterocyclic groups include aromatic heterocyclic groups (heteroaryl groups) and aliphatic heterocyclic groups), and alkoxy groups (preferably having 1 to 20 carbon atoms). Or 1 to 12), alkenyloxy group (preferably 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms), alkynyloxy group (preferably 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms), cycloalkyloxy groups Group (preferably 3 to 20 carbon atoms), aryloxy group (preferably 6 to 26 carbon atoms, more preferably 6 to 14 carbon atoms), heterocyclic oxy group (preferably 2 to 20 carbon atoms),

Alkoxycarbonyl group (preferably having a carbon number of 2 to 20), cycloalkoxycarbonyl group (preferably having a carbon number of 4 to 20), aryloxycarbonyl group (preferably having a carbon number of 6 to 20), amino group (preferably having a carbon number of 0 to 10) 20, unsubstituted amino group (-NH ₂ ), (mono- or di-) alkylamino group, (mono- or di-) alkenylamino group, (mono- or di-) alkynylamino group, (mono- or di-) Di-) cycloalkylamino group, (mono- or di-) cycloalkenylamino group, (mono- or di-) arylamino group, (mono- or di-) heterocyclic amino group, and unsubstituted amino group Each group to be substituted has the same meaning as the corresponding group in the substituent group T.), a sulfamoyl group (preferably having a carbon number of 0 to 20, alkyl, cycloalkyl or aryl). Sulfamoyl group is preferred), an acyl group (preferably having 1 to 20 carbon atoms, more preferably 2 to 15 carbon atoms), an acyloxy group (preferably having 1 to 20 carbon atoms), a carbamoyl group (preferably having 1 to 20 carbon atoms). Preferably an alkyl, cycloalkyl or aryl carbamoyl group),

Acylamino group (preferably having a carbon number of 1 to 20), sulfonamide group (preferably having a carbon number of 0 to 20, preferably an alkyl, cycloalkyl or aryl sulfonamide group), alkylthio group (preferably having a carbon number of 1 to 20) , More preferably 1 to 12), cycloalkylthio group (preferably having a carbon number of 3 to 20), arylthio group (preferably having a carbon number of 6 to 26), heterocyclic thio group (preferably having a carbon number of 2 to 20), alkyl, A cycloalkyl or arylsulfonyl group (preferably having a carbon number of 1 to 20),

A silyl group (preferably a silyl group having 1 to 20 carbon atoms and substituted by alkyl, aryl, alkoxy or aryloxy is preferable), a silyloxy group (preferably having 1 to 20 carbon atoms, alkyl, aryl, alkoxy or aryloxy Siloxy groups are preferred), hydroxy groups, cyano groups, nitro groups, halogen atoms (eg fluorine atom, chlorine atom, bromine atom or iodine atom), carboxy group (—COOH), phosphonyl group (—PO (OH) ) _2), a phosphoryl group _{(-O-PO (OH) 2} ), a sulfo group _(-SO 3 H), boric acid, hydroxy group, or, mercapto group.

  The substituent selected from Substituent group T is more preferably an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, a heterocyclic group, an alkoxy group, a cycloalkoxy group, an aryloxy group, an alkoxycarbonyl group, a cycloalkoxycarbonyl Group, amino group, acylamino group, cyano group or halogen atom, particularly preferably alkyl group, alkenyl group, aryl group, heterocyclic group, alkoxy group, alkoxycarbonyl group, amino group, acylamino group or cyano group .

  The substituent selected from Substituent Group T also includes a group formed by combining a plurality of the above-mentioned groups unless otherwise specified. For example, when the compound or substituent or the like contains an alkyl group, an alkenyl group or the like, these may be substituted or unsubstituted. In addition, when the aryl group, the heterocyclic group and the like are contained, they may be monocyclic or fused ring, and may be substituted or unsubstituted.

  Specific examples of the compound (I) represented by the general formula (I) are shown below and in the Examples, but the present invention is not limited to these compounds (I). In the following specific examples, Me is methyl and Et is ethyl.

The above compound (I) contained in the wavelength conversion composition of the present invention may be one kind or two or more kinds.
The content of the compound (I) in the wavelength conversion composition of the present invention is not particularly limited, and is appropriately determined according to the molar absorptivity of the compound, the required quantum yield, or the absorption intensity. For example, the content is preferably 0.1 to 50 parts by mass, more preferably 0.5 to 40 parts by mass, still more preferably 1 to 30 parts by mass, with respect to 100 parts by mass of a binder resin described later. 20 parts by weight are particularly preferred, and 1 to 10 parts by weight are most preferred. In addition, when the wavelength conversion composition of this invention contains 2 or more types of said compound (I), let said content be the total content of each compound (I).

<Binder resin>
The wavelength conversion composition of the present invention contains a binder resin.
In the present invention, the binder resin is at least one of a silicone resin and an epoxy resin, preferably a silicone resin or an epoxy resin, and in terms of the dispersibility (insolubility) of the compound (I), the silicone resin is More preferable. When a silicone resin or an epoxy resin is used as a binder resin, the compound (I) can be dispersed in a solid state in the binder resin.
In the present invention, when the binder resin is a thermosetting or photocurable resin, the binder resin is a compound that forms a monomer of the binder resin and a component of the binder resin in addition to the binder resin (pre-polymerization Precursor).

In the present invention, silicone resins include epoxy silicone resins and silicone elastomers.
Although it does not specifically limit as a silicone resin, An aliphatic silicone resin and an aromatic silicone resin are mentioned, An aliphatic silicone resin is preferable. Examples of aliphatic silicone resins include methyl silicone resins and dimethyl silicone resins. Examples of aromatic silicone resins include methyl phenyl silicone resins and diphenyl silicone resins. In addition, the silicone resin may be addition reaction curable (thermosetting).
Although it does not specifically limit as an epoxy resin, An aliphatic epoxy resin and an aromatic epoxy resin are mentioned, An aliphatic epoxy resin is preferable.

The weight average molecular weight of the binder resin is not particularly limited, but may be, for example, 1,000 to 100,000.
The binder resin is preferably transparent or translucent (the transmittance of visible light (wavelength 300 to 830 nm) is 50% or more).

  The binder resin contained in the wavelength conversion composition of the present invention may be one type, or two or more types.

<Additives>
The wavelength conversion composition of the present invention may contain various additives generally used in the wavelength conversion composition. As such additives, for example, photoluminescent phosphors other than the above compound (I), inorganic phosphors, dyes for color tone correction, processing, oxidation and heat stabilizers (antioxidants, phosphorus processing stability) Agents), light resistance stabilizers (ultraviolet absorbers etc.), silane coupling agents, organic acids, matting agents, radical scavengers, antidegradants, fillers (eg, silica, glass fibers, glass) Beads), plasticizers, lubricants, flame retardants (eg, organic halogen compounds), flame retardant aids, antistatic agents, antistatic agents, impact modifiers, impact modifiers, discoloration inhibitors, release agents (eg, monovalent resins) Or higher fatty acid esters of polyhydric alcohols, flow improvers, reactive or non-reactive diluents, and the like.

  Although it does not specifically limit as photoluminescent fluorescent substance other than a compound (I), Well-known photoluminescent fluorescent substance (dye) is mentioned. Specific examples of the various additives include “other components” and “solvents” described in Patent Document 3, or those described in JP-A-2011-241160, and the like. Is preferably incorporated herein. Further, the content of the additive is not particularly limited, and is appropriately determined as long as the object of the present invention is not impaired.

In the wavelength conversion composition of the present invention, the compound (I) represented by the general formula (I) is dispersed in the solid state in the binder resin.
The form of the wavelength conversion composition of the present invention is not particularly limited as long as the compound (I) is in a predetermined dispersion state. For example, the form which contains binder resin and said compound (I) in a particulate form is mentioned. In another embodiment, the binder resin forms a continuous phase, in which the above compound (I) is dispersed in a solid state. The wavelength conversion composition of the present invention can be used as a material of a wavelength conversion portion described later in any form. When the binder resin forms a continuous phase, the wavelength conversion composition is also referred to as a wavelength conversion portion described later, although the shape is not specified.

When the binder resin is a solid, the wavelength conversion composition of the present invention is a solid dispersion in which a solid compound (I) is dispersed in a solid binder resin. On the other hand, when the binder resin is liquid or liquid, the wavelength conversion composition of the present invention is a liquid composition (suspension) in which a solid compound (I) is dispersed in a liquid binder resin.
The wavelength conversion composition of the present invention may contain the above-mentioned diluent (water, solvent or the like) in the range where the compound (I) is dispersed in the binder resin in a solid state.

The wavelength conversion composition of the present invention can convert incident light into light having a wavelength longer than that of the incident light, and exhibits high quantum yield and excellent durability. The red light obtained by wavelength-converting the incident light can be emitted with a high quantum yield over a long period of time even if it is used for the wavelength conversion portion, particularly the wavelength conversion portion disposed close to the light source. The quantum yield which the wavelength conversion composition of this invention shows is the same as the quantum yield which the wavelength conversion part used for the light-emitting device of this invention shows. Particularly preferably, it can be used as a wavelength conversion material for a white LED, and also in this case, high quantum yield and excellent durability can be maintained.
Although the details of the reason why the wavelength conversion composition of the present invention emits red light with a high quantum yield over a long period of time are not clear yet, it is considered as follows.
When Compound (I) is used in the wavelength conversion composition of the present invention in combination with the above binder resin, it is difficult to dissolve in, dissolve or dissolve in the binder resin, and molecules of Compound (I) aggregate in the binder resin. Disperse in the solid state. At this time, it is considered that the compound (I) suppresses aggregation-induced quenching even in a solid state, and exhibits high quantum yield. In addition, since the light is dispersed in a solid state, it is possible to emit emitted light (red light) of a target wavelength by suppressing wavelength change when converting the wavelength of incident light. Thus, compound (I) exhibits excellent solid-state light emission characteristics. Moreover, since the compound (I) is aggregated (exists in close proximity), it is considered that the decomposition of the compound (I) itself by light or heat is suppressed by the interaction generated between the molecules.
Therefore, the wavelength conversion composition of the present invention containing the compound (I) and the above-mentioned binder resin can achieve both quantum yield and durability at a high level.

  The compound (I) usually has a high light absorption amount per mass as compared to the inorganic photoluminescent phosphor. Therefore, the wavelength conversion composition of the present invention containing the compound (I) exhibits high emission intensity. When the emission intensity of the wavelength conversion composition of the present invention is set to the same emission intensity as that of the wavelength conversion composition containing an inorganic photoluminescent phosphor, the content of the compound (I) can be reduced (compound Even when the content of (I) is reduced, emission intensity equivalent to or higher than that of the wavelength conversion composition containing an inorganic photoluminescent phosphor can be realized. Therefore, light scattering by the compound (I) can be suppressed, and light extraction efficiency can also be enhanced.

<Method of preparing wavelength conversion composition>
The method for producing the wavelength conversion composition of the present invention is not particularly limited, and, for example, a photoluminescent phosphor (including at least one compound (I)), a monomer of a binder resin and / or a binder There is a method of curing a composition containing a resin and a polymerization precursor.

  For example, after dispersing a photoluminescent fluorescent substance in the monomer and / or the polymerization precursor of binder resin which form binder resin, the method of polymerizing the above-mentioned monomer and / or the polymerization precursor is mentioned. Moreover, after suspending a photoluminescent fluorescent substance in the solution of the said monomer and / or polymerization precursor, the method of polymerizing a monomer and / or a polymerization precursor is also mentioned. Here, to suspend the photoluminescent phosphor in the solution means, for the compound (I) as the photoluminescent phosphor, the above-mentioned "the compound (I) is dispersed in the solid state in the binder resin" It is synonymous with.

  When using the said monomer and / or polymerization precursor as binder resin, the following method is mentioned as a method of disperse | distributing or suspending a photoluminescent fluorescent substance to a monomer and / or a polymerization precursor. When the monomer and / or the polymerization precursor is liquid, for example, a paint shaker, a mixer and a homogenizer are used to disperse or suspend the photoluminescent phosphor in the liquid of the monomer and / or the polymerization precursor There is a way to In addition, when the monomer and / or the polymerization precursor is solid, for example, the photoluminescent phosphor is dispersed or suspended in the powder of the monomer and / or the polymerization precursor using a ball mill, a sand mill, etc. There is a way to

The polymerization method in this method is not particularly limited, and may be thermal polymerization or photopolymerization.
Thermal polymerization can be performed by a conventional method. As a thermal polymerization method, for example, a method of adding a catalyst to a mixture of the above-mentioned monomer and / or polymerization precursor and photoluminescent phosphor as needed and heating can be mentioned. About the thermal polymerization method and its conditions, the catalyst to be used further, and its use amount, the method etc. which were described in Unexamined-Japanese-Patent No. 2011-241160 are mentioned, The description of this gazette is preferably taken in to this specification.

  Photopolymerization can be performed by a conventional method. As the photopolymerization method, for example, a method of adding a photopolymerization initiator to the mixture of the monomer and / or the polymerization precursor and the photoluminescent phosphor as required, and then irradiating the light may be mentioned. About the photopolymerization method and its conditions, the polymerization initiator to be used further, and its using amount, the method of Unexamined-Japanese-Patent No. 2011-241160 etc. is mentioned, The description of this gazette is preferably taken in to this specification.

  When the binder resin is a silicone resin, a method of polymerizing by addition curing reaction is preferable. The addition curing reaction of the silicone resin can also be carried out in a conventional manner. For example, polymerization is preferably performed by a hydrosilylation reaction of an organosiloxane having a polymerizable reactive group (for example, an alkenyl group) and a hydrogen siloxane having a hydrogen atom bonded to a silicon atom. The conditions for the hydrosilylation reaction are not particularly limited, but include heating to room temperature or higher, for example, 50 to 200 ° C. in the presence of an addition reaction catalyst (eg, platinum), if desired.

  The polymerization may be carried out without a solvent or in a solvent. When the polymerization is carried out in a solvent, the organic solvent used for the polymerization is not particularly limited. For example, hydrocarbon solvents, ketone solvents, halogenated hydrocarbon solvents, ester solvents, alcohol solvents, ether solvents, N, N-dimethyl Polar solvents such as formamide, N, N-dimethylacetamide, 1-methyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, dimethylsulfoxide and the like can be mentioned. The organic solvents may be used alone or in combination of two or more.

  As a method of removing the organic solvent, a method of heating the mixed organic solvent solution to a temperature not lower than the boiling point of the organic solvent and not higher than the decomposition temperature of the binder resin and the photoluminescent phosphor can be mentioned. At this time, it can also be removed under reduced pressure (less than atmospheric pressure).

  Other than the above method, there may be mentioned a method including a step of melt-mixing a composition containing a photoluminescent phosphor and a binder resin. In this method, the method of melt mixing can be applied without particular limitation to known methods, and melt mixing conditions can also be set appropriately.

[Light Emitting Device]
The light-emitting device of the present invention has a wavelength conversion unit made of the wavelength conversion composition of the present invention and a light source, and emits the desired wavelength light. The wavelength converter absorbs light (incident light) emitted (emitted) from the light source, and emits light (emitted light) having a specific wavelength (preferably longer than the wavelength of the incident light) different from this light. It has a function to emit light (wavelength conversion). At this time, the wavelength conversion unit absorbs all or part of the light from the light source and emits light of a specific wavelength. For example, when the light emitting device of the present invention emits white light as a whole (white LED or white illumination, etc.), the wavelength converter absorbs a part of the light from the light source and converts it into red light. Together with the rest of the light from the light source (blue light and (wavelength converted) green light), white light can be emitted as the whole device.
As a structure of the light emitting device of the present invention, a conventionally known structure can be applied without particular limitation. Details will be described later.
In the light emitting device of the present invention, the arrangement of the wavelength conversion unit and the light source is not particularly limited, and the wavelength conversion unit and the light source may be arranged in proximity or in contact with each other. It may be arranged in the state which intervened. Since the wavelength conversion composition and the wavelength conversion unit of the present invention exhibit excellent durability as described above, the wavelength conversion unit and the light source can be disposed close to each other, and the wavelength conversion unit and the light source are in contact with each other. It can also be placed in the Even if such an arrangement is adopted, it is possible to emit red light obtained by wavelength-converting incident light with a high quantum yield over a long period of time.
The light emitting device of the present invention is preferably used as a white LED or as a white LED, and also in this case, it exhibits high quantum yield and excellent durability.

<Wavelength converter>
The shape, dimensions, and the like of the wavelength conversion portion are not particularly limited as long as they are made of the wavelength conversion composition of the present invention, and are appropriately set according to the application and the like. For example, the wavelength conversion portion used in the light emitting device of the present invention may be the wavelength conversion composition of the present invention itself or may be a molded body. When it is the wavelength conversion composition of the present invention itself, it is usually formed by applying (applying or arranging) the wavelength conversion composition of the present invention to the installation surface. When it is a molded body, the shape is not particularly limited, and examples thereof include a film, a plate (for example, a sheet, a filter, and a disc), a lens, a fiber, an optical waveguide, and the like.
The wavelength converter is one of the preferred embodiments in a plate shape. In this case, the wavelength conversion portion (also referred to as a wavelength conversion filter) may be formed as a wavelength conversion layer made of the wavelength conversion composition of the present invention. Although the thickness of a wavelength conversion layer is not specifically limited, For example, 10-3000 micrometers is preferable, and 30-2000 micrometers is more preferable.

The wavelength conversion unit may be a laminate (wavelength conversion member) provided on a substrate or the like.
The substrate includes a glass substrate or a polymer substrate. Examples of the glass substrate include substrates made of glass such as soda lime glass, glass containing barium and strontium, lead glass, aluminosilicate glass, borosilicate glass, barium and borosilicate glass, quartz and the like. Examples of the polymer substrate include substrates made of polymers such as polycarbonate, acrylic resin, polyethylene terephthalate, polyether sulfide, polysulfone and the like.

  The wavelength converter may have components other than the substrate. Such components are not particularly limited as long as they are generally used for wavelength conversion members, and examples include protective films (films) and the like.

The wavelength conversion unit can emit red light obtained by wavelength-converting incident light with a high quantum yield over a long period of time.
The quantum yield indicated by the wavelength converter is preferably 0.3 or more, more preferably 0.4 or more, and still more preferably 0.5 or more. The upper limit of the quantum yield is not particularly limited, but is generally 1.0 or less. In the present invention, the quantum yield can be measured using a commercially available quantum yield measurement apparatus, for example, an absolute PL (photoluminescence) quantum yield measurement apparatus: C9920-02 (manufactured by Hamamatsu Photonics Co., Ltd.) It can be used and measured about a wavelength conversion part (432 micrometers in thickness).

When the wavelength conversion part is a molded body, it is manufactured by molding the wavelength conversion composition of the present invention into a predetermined shape.
The molding method is not particularly limited, and a molding method performed in a hot-melted state such as injection molding, the wavelength conversion composition of the present invention is melted (compound (I) is dispersed in a solid state in a binder resin And the like). The film forming method is not particularly limited. For example, spin coating method, roll coating method, bar coating method, Langmuir-Blodgett method, casting method, dip method, screen printing method, bubble jet (registered trademark) method, inkjet Methods, vapor deposition methods, electric field methods and the like.
When the binder resin is a thermosetting or photocurable resin, the mold is filled with a composition obtained by mixing the monomer of the binder resin and / or the polymerization precursor and the photoluminescent phosphor, or It is also possible to apply the above method of forming a film by a film forming method and polymerizing by light or heat.

<Light source>
The light source used in the light emitting device of the present invention emits a light emission wavelength (wavelength light) capable of exciting at least the compound (I), preferably all of the photoluminescent phosphors contained in the wavelength conversion portion. There is no particular limitation. Such light sources include, for example, incandescent lamps, metal halide lamps, HID lamps (high intensity discharge lamps: high intensity discharge lamps), xenon lamps, sodium lamps, mercury lamps, fluorescent lamps, cold cathode tubes, cathode luminescence, low speed electrons Wire tube, light emitting diode [eg GaP (red, green), GaP _x As _(1-x) (red, orange, yellow: 0 <x <1), Al _x Ga _(1-x) As (red: 0 ₎ <X <1), GaAs (red), SiC (blue), GaN (blue), ZnS, ZnSe], electroluminescence (e.g., inorganic EL using ZnS host and luminescent center, organic EL (e.g., non-patent literature) 1 and the compound described in Patent Document 1), laser (eg, He-Ne) Za, CO ₂ laser, Ar, Kr, He-Cd laser, an excimer laser, a gas laser of nitrogen laser, a ruby laser, yttrium - aluminum - garnet (YAG) laser, solid laser, dye laser glass laser, a semiconductor laser ), Sunlight etc. can be mentioned.
The light source is preferably a light emitting diode, an electroluminescence or a semiconductor laser, and more preferably a light emitting diode.

The light emitting diode is preferably a semiconductor light emitting element having a light emitting layer capable of emitting at least a light emitting wavelength capable of exciting the compound (I). As such a semiconductor light emitting element, one in which the light emitting layer contains the above semiconductor can be mentioned. As the semiconductor other than the above semiconductor compounds capable of emitting nitride semiconductor short wavelength that can efficiently excite the _{(I) (In x Al y} Ga (1-x-y), 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) is preferred. More preferably, the light emitting layer contains no compound (I). The semiconductor contained in the light emitting layer is preferably an inorganic semiconductor. The structure of the semiconductor includes a homostructure, a heterostructure or a double heterostructure having a MIS (Metal-Insulator-Silicon) junction, a PIN junction, a pn junction and the like. Various emission wavelengths can be selected depending on the material of the light emitting layer or the mixed crystal ratio thereof. In addition, the light emitting layer can be a single quantum well structure or a multiple quantum well structure formed in a thin film in which a quantum effect occurs.

  When white light is emitted to the light emitting device of the present invention, which will be described later, the light emission wavelength (excitation wavelength) of the light source is determined in consideration of the complementary color relationship with the light emission wavelength from compound (I) or the deterioration of the binder resin. 350-480 nm is preferable. In order to further improve the excitation of the light source and the compound (I) and the emission efficiency, the emission wavelength is more preferably 380 to 450 nm. Light emitting diodes are usually disposed on a substrate having a patterned metal such as copper foil. Here, as a substrate material, an insulating organic compound or an inorganic compound (for example, glass, ceramics) may be mentioned. As the organic compound, various polymer materials (for example, epoxy resin, acrylic resin) can be used. Further, the shape of the substrate is not particularly limited, and various shapes such as a plate shape, a cup shape, and a porous plate shape can be selected.

Although the said semiconductor laser is not specifically limited, The thing by the following mechanism is preferable. That is, the semiconductor is pn junction, forward bias is applied thereto, minority carriers at high energy levels are injected, and electrons flowed into the p-type region are flowed into holes and n-type regions. Recombine holes with electrons. As a result, there is a mechanism that causes an electron to transition from a high energy level to a low energy level and emits a photon corresponding to the energy difference.
Examples of the material of the semiconductor laser include Group IV elements such as germanium and silicon, and direct transition III-V and II-VI compounds without lattice vibration such as GaAs and InP. Further, these materials may be not only binary systems but also multi-systems such as ternary systems, quaternary systems, five-system systems and the like. In addition, the laminated structure may be a double hetero structure provided with a cladding layer, or may be configured by a lower cladding, an active layer, and an upper cladding. Furthermore, a multiple quantum well structure may be applied.

  The light-emitting device of the present invention may optionally include a color filter to adjust the color purity. The color filter is not particularly limited as long as it is usually used. Examples of pigments used for color filters include perylene pigments, lake pigments, azo pigments, quinacridone pigments, anthraquinone pigments, anthracene pigments, isoindoline pigments, isoindolinone pigments, phthalocyanine pigments, triphenylmethane basic dyes, indanthrone pigments Various pigments such as pigments, indophenol pigments, cyanine pigments, dioxazine pigments, etc., or a mixture of two or more of these pigments, and further, a mixture of the above pigment or a mixture of pigments and a binder resin (dissolved or dispersed in solid state Thing) is mentioned.

In the light emitting device of the present invention, the compound (I) observes the incident light from the light source, preferably the incident light in the above wavelength region, in a high quantum yield and a red emission light (peak wavelength is in the region of 580 to 750 nm) To emit light for a long period of time. The quantum yield is as described above.
The light emitted by the light emitting device of the present invention as a whole may be only light which has been wavelength converted by the compound (I) or the wavelength converter, or may be a mixed light of this light and the above-mentioned wavelength light from the light source. Furthermore, it may be a mixed light of these and light obtained by converting the wavelength light from the light source into light of a wavelength other than red (for example, green light).

<Structure of light emitting device>
The configuration of the light emitting device of the present invention is not particularly limited, but the following configurations may be mentioned.
As a specific configuration, for example, a light source / wavelength conversion unit, a light source / translucent substrate / wavelength conversion unit, a light source / wavelength conversion unit / translucent substrate, a light source / translucent substrate / wavelength conversion unit / translucency Substrate, light source / wavelength converter / color filter, light source / translucent substrate / wavelength converter / color filter, light source / wavelength converter / translucent substrate / color filter, light source / translucent substrate / wavelength converter / Each structure of a translucent substrate / color filter, a light source / translucent substrate / wavelength conversion part / color filter / translucent substrate, a light source / wavelength conversion part / color filter / translucent substrate is mentioned. In each of the above configurations, the wavelength conversion portion is made of the wavelength conversion composition of the present invention. In addition to this, it may have another wavelength conversion part which performs wavelength conversion to wavelength light (for example, green light) other than red. In this case, the arrangement relationship between the wavelength conversion unit made of the wavelength conversion composition of the present invention and another wavelength conversion unit is not particularly limited, and may be, for example, arranged in parallel. In each of the above configurations, the components are disposed in contact with or separated from each other.

  The said translucent substrate means the board | substrate which can permeate | transmit 50% or more of visible light, and, specifically, it is synonymous with the base material which the said wavelength conversion part may have. Further, the color filter is also synonymous with the color filter that the wavelength conversion unit may have. The shapes of the light-transmissive substrate and the color filter are not particularly limited, and may be plate-like or lens-like.

The light emitting device of the present invention can be used for various applications, and preferably includes display devices such as various displays, lighting devices, and the like.
The display device is not particularly limited, and examples thereof include various displays, traffic signals, traffic display devices, liquid crystal backlights, liquid crystal front lights, field sequential liquid crystal displays, and the like. The illumination device is not particularly limited, and examples thereof include general illumination devices (instruments), local illumination devices, interior illumination devices, and the like.

  The light emitting device of the present invention can be manufactured by a known method. For example, the components used in the above-described configuration can be sequentially stacked and manufactured, or the components can be bonded and manufactured. The stacking order of the components is not particularly limited.

  The present invention will be described in more detail based on the following examples, but the present invention is not limited thereto.

  Compounds (1) to (5) as compounds (I) and comparative compounds (1) to (3), which are photoluminescent phosphors used in Examples and Comparative Examples, are shown below. In the following compounds, Et represents ethyl.

The comparison compound (1) is a compound IV described in paragraph [0050] of Patent Document 2.
The comparison compound (2) is rhodamine B.
The comparison compound (3) is the benzene compound 5 described in paragraph [0183] of Patent Document 1.

The synthesis methods of the compounds (1) to (5) used in each example will be described in detail below, but the starting materials, dye intermediates and synthesis routes are not limited to these.
In the present invention, room temperature means 25 ° C.

Synthesis Example 1: Synthesis of Compound (1) Compound (1) was synthesized based on the following scheme.
In the following scheme, Et represents ethyl.

In a 200 mL three-necked flask, 500 mg of 2,5-dibromoterephthalaldehyde, 401 mg of phenylacetonitrile and 30 mL of ethanol were introduced and stirred at room temperature. Thereto, 1.01 g of sodium hydroxide was added, and the mixture was further stirred at room temperature for 1 hour. Thereafter, 30 mL of distilled water was added to the reaction solution, the solid was removed by filtration, washed with 20 mL of distilled water and 10 mL of ethanol, and dried to obtain 770 mg of compound (1-A).
Into a 50-mL eggplant flask, 0.49 g of compound (1-A), 1.69 g of diphenylamine, 2.12 g of tripotassium phosphate, and 4 mL of toluene were introduced, and the mixture was degassed under reduced pressure while stirring at room temperature and then made into a nitrogen atmosphere. . Here, Pd—RuPhos G3 (2-dicyclohexylphosphino-2 ′, 6′-diisopropoxy-1,1′-biphenyl) [2- (2′-amino-1,1′-biphenyl)] palladium II) Methanesulfonate (manufactured by Aldrich) 125 mg was added and heated to reflux for 7 hours. After the reaction, 50 mL of distilled water and 50 mL of chloroform were added, extraction and separation were performed, the organic layer obtained was predried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was washed with 10 mL of tertiary butyl methyl ether and recrystallized with chloroform and hexane to obtain 500 mg of a compound (1).
Compound (1) was identified by ESI-MS (electrospray ionization mass spectrometry). The results are shown below.
ESI-MS: [M-H] ⁻ = 665

Synthesis Example: Synthesis of Compound (2) In the synthesis of the compound (1), the above compound (1) was used except that phenylacetonitrile was replaced with ethyl cyanoacetate (the amount used was adjusted to be the same molar amount). The compound (2) was synthesized in the same manner as in the synthesis of
Compound (2) was identified by ESI-MS. The results are shown below.
ESI-MS: [M-H] ⁻ = 657

Synthesis Example 3 Synthesis of Compound (3) In the synthesis of the compound (1), phenylacetonitrile was replaced by ethyl phenylacetate and diphenylamine was replaced by 9,10-dihydro-9,9-dimethylacridine (the amount used) The compound (3) was synthesized in the same manner as in the synthesis of the compound (1) except that the (1) was adjusted to the same molar amount.
Compound (3) was identified by ESI-MS. The results are shown below.
ESI-MS: [M-H] ⁻ = 640

Synthesis Example 4 Synthesis of Compound (4) In the synthesis of the compound (1), except that diphenylamine was replaced with N-methylaniline (the amount used was adjusted to be the same molar amount), the above compound (the amount used was the same) The compound (4) was synthesized in the same manner as in 1).
Compound (4) was identified by ESI-MS. The results are shown below.
ESI-MS: [M-H] ⁻ = 541

Synthesis Example 5 Synthesis of Compound (5) A compound (5) was synthesized based on the following scheme.
In the following scheme, Et is ethyl and Bu is butyl.

In a 200 mL three-necked flask, under nitrogen atmosphere, 1.08 g of compound (5-A), 0.76 g of tertiary butoxy potassium, and 40 mL of THF were added, and stirred at room temperature. Thereto, 0.78 g of 3,5-difluoro-4-formylbenzonitrile was added, and the mixture was further stirred at room temperature for 1 hour. Thereafter, 40 mL of distilled water was added to the reaction solution, the solid was removed by filtration, washed with 40 mL of distilled water and 20 mL of ethanol, and dried to obtain 822 mg of compound (5-B).
Next, 0.56 g of compound (5-B), 1.69 g of diphenylamine, 2.12 g of tripotassium phosphate, and 4 mL of toluene are introduced into a 50 mL recovery flask, degassed under reduced pressure while stirring at room temperature, and then nitrogen atmosphere did. Here, 125 mg of Pd-RuPhos G3 (manufactured by Aldrich) was added, and the mixture was heated to reflux for 7 hours. After the reaction, 50 mL of distilled water and 50 mL of chloroform were added, extraction and separation were performed, the organic layer obtained was predried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was washed with 10 mL of tert-butyl methyl ether and recrystallized with chloroform and hexane to give 474 mg of compound (5).
Compound (5) was identified by ESI-MS. The results are shown below.
ESI-MS: [M-H] ^- = 737

Example 1
<Production of wavelength conversion composition (film-like wavelength conversion member)>
1 g of solution A and 1 g of solution B were mixed with a silicone resin (KER-2500, two-component mixture addition cure type, manufactured by Shin-Etsu Chemical Co., Ltd.), and then 20 mg of Compound (1) as a photoluminescent phosphor 1 part by mass with respect to parts by mass) were added, mixed at 2000 rpm (rotation per minute) with an autorotation / revolution mixer (manufactured by Shinky Co., Awatori Fukuro), and defoamed at 2200 rpm. The obtained mixed solution (the compound (1) was dispersed in the binder resin in a solid state) was spin-coated on a glass plate at 1000 rpm, and heated at 150 ° C. for 2 hours to be cured. Thus, a wavelength conversion composition (film-like wavelength conversion member) was produced. The thickness of the obtained wavelength conversion layer was 432 μm.

Examples 2 to 5 and Comparative Examples 3 to 5
A wavelength conversion composition (film-like) was prepared in the same manner as in Example 1 except that the compound shown in the following Table 1 or a comparative compound was used as a photoluminescent phosphor in place of the compound (1) in Example 1. The wavelength conversion members of

Comparative Example 1
After dissolving 1 g of polymethyl methacrylate (PMMA, manufactured by Aldrich) in 10 mL of toluene, 10 mg of the comparison compound (1) (1 part by mass with respect to 100 parts by mass of the binder resin) is dissolved as a photoluminescent phosphor A dye resin solution was prepared. The dye resin solution was spin-coated on a glass plate at 1000 rpm and then dried on a hot plate at 50 ° C. to produce a wavelength conversion composition (a film-like wavelength conversion member).
Comparative Examples 2, 6 and 7
In Comparative Example 1, a wavelength conversion composition (a film was prepared in the same manner as Comparative Example 1 except that the compounds shown in the following Table 1 or the comparative compounds were used as a photoluminescent phosphor instead of Comparative Compound (1). Shaped wavelength conversion members) were produced.

[Evaluation of wavelength conversion composition (film-like wavelength conversion member)]
The following characteristics of the produced wavelength conversion composition (film-like wavelength conversion member) were evaluated, and the results are shown in Table 1.

<Evaluation of distributed state>
About the produced film-form wavelength conversion member, the dispersion state (solubility to binder resin) of photoluminescence fluorescent substance was confirmed.
The evaluation was carried out using an absolute PL quantum yield measuring apparatus: C9920-02 (manufactured by Hamamatsu Photonics K. K.) for a test piece obtained by cutting the continuous phase (film) of the produced film-like wavelength conversion member into 15 mm × 15 mm. The fluorescence spectrum was measured. In the obtained spectrum, the peak intensity of the maximum emission wavelength (aggregation / association emission wavelength) in the dispersed state of the photoluminescent phosphor and the maximum emission wavelength in the dissolved state (shorter than the above aggregation / association emission wavelength) Alternatively, the peak intensity of the long wavelength peak is determined, and the maximum emission wavelength intensity in the dispersed state and the maximum emission wavelength intensity in the dissolved state are respectively determined. The intensity ratio of the maximum emission wavelength intensity of the dissolved state to the maximum emission wavelength intensity of the dispersed state [maximum emission wavelength intensity of the dissolved state / maximum emission wavelength intensity of the dispersed state] was calculated.
It was determined which of the following evaluation ranks the calculated intensity ratio is included.
In this test, when the evaluations are “A” and “B”, it indicates that the photoluminescent phosphor is well dispersed in the binder resin in the solid state.
-Evaluation rank-
A: less than 0.2 B: 0.2 or more, less than 1.0 C: 1.0 or more

<Measurement of quantum yield>
The quantum yield was measured about the produced film-form wavelength conversion member using absolute PL quantum yield measuring apparatus: C9920-02 (made by Hamamatsu Photonics company). The excitation wavelength was 405 nm.
It was determined in which of the following evaluation ranks the measured quantum yield was included.
In this test, the quantum yield is practically required to be equal to or higher than the evaluation rank "C".
In Comparative Examples 6 and 7, the dispersion state of the compounds (1) and (2) is bad, and the quantum yield is not evaluated.
-Evaluation rank-
A: 0.5 or more B: 0.4 or more, less than 0.5 C: 0.3 or more, less than 0.4 D: 0.2 or more, less than 0.3 E: less than 0.2

<Evaluation of durability>
The durability test was implemented about the produced film-form wavelength conversion member.
The wavelength conversion member is continuously irradiated with violet light of 405 nm at a luminous flux density of 4.0 W / cm ² in an atmosphere at a temperature of 80 ° C., and the emission intensity is measured immediately after the irradiation and at predetermined time intervals. , Fluorescence spectrophotometer: measured by RF-5300PC (manufactured by Shimadzu Corporation). The durability of the wavelength conversion member was evaluated at an irradiation time in which the light emission intensity after a predetermined time decreased by 10% with respect to the light emission intensity immediately after the irradiation. It was determined in which of the following evaluation ranks the irradiation time was included.
In this test, durability is practically required to be evaluation rank "C" or higher.
-Evaluation rank-
A: 200 hours or more B: 100 hours or more, less than 200 hours C: 50 hours or more, less than 100 hours D: 10 hours or more, less than 50 hours E: less than 10 hours

<Evaluation of wavelength conversion performance (emission light)>
When the film-like wavelength conversion member produced in Example 1 was excited with light of 405 nm, it was confirmed that red light with a maximum emission wavelength of 600 nm was observed (emitted). The maximum emission wavelength was in agreement with the solid emission wavelength of the compound (1).
Moreover, the wavelength conversion performance was similarly evaluated about the film-form wavelength conversion member produced in Example 5. As a result, it was confirmed that red light with a maximum emission wavelength of 620 nm was observed (emitted). The maximum emission wavelength was in agreement with the solid emission wavelength of the compound (5).
Similar results were obtained for the other compounds used in the examples.
Furthermore, the wavelength conversion performance of the film-like wavelength conversion members produced in Comparative Examples 1 and 2 was also evaluated in the same manner. As a result, the maximum emission wavelength was shortened so as to exceed 30 nm with respect to the solid emission wavelengths of the comparative compounds (1) and (2).

From the results of Table 1, the following can be seen.
Whether a wavelength conversion composition (wavelength conversion member) containing no compound represented by the above general formula (I) defined in the present invention as a photoluminescent phosphor is dispersed in a binder resin in a solid state or not Nevertheless, neither quantum yield nor durability is sufficient.
The comparative compound (1) and the rhodamine B used for the wavelength conversion element do not exhibit high quantum yield and excellent durability even if they are dissolved in a binder resin or dispersed in a solid state (comparative example) 1-4). In addition, even when using the comparison compound (3) in which Ar ¹ , Ar ² , R ¹ and R ² in general formula (I) defined in the present invention are all alkyl groups, the quantum yield and the durability can be satisfied. It is not a thing (comparative example 5). Furthermore, when PMMA is used as the binder resin, the compound represented by the general formula (I) defined in the present invention can not be dissolved in the binder resin and can not exhibit excellent solid luminescence characteristics.

  On the other hand, a wavelength conversion composition (wavelength conversion member) containing a compound (I) represented by the general formula (I) defined in the present invention as a photoluminescent phosphor and a silicone resin as a binder resin In the binder resin, the compound (I) is dispersed in a solid state. Also, this wavelength conversion composition exhibits high quantum yield and excellent durability. Therefore, it is understood that the wavelength conversion composition of the present invention and the light emitting device using the same can emit emitted light obtained by wavelength converting incident light into red light with a high quantum yield over a long period of time (Examples 1 to 4) 5). Thus, the compound (I) represented by the general formula (I) is dispersed in a solid state without being dissolved in the binder resin, and exhibits the above-mentioned excellent solid light emission characteristics.

[Manufacturing and evaluation of light emitting device]
Examples 6 to 10
The light emitting devices of Examples 6 to 10 were manufactured using the wavelength conversion members manufactured in Examples 1 to 5 and a violet LED (model number: PS2N-UFLE, manufactured by Prolight Opto). About the manufactured light-emitting device, it carried out similarly to said <measurement of a quantum yield> and <evaluation of durability>, and measured the quantum yield and evaluated durability. As a result, the same excellent results as those of Examples 1 to 5 were obtained in any of the light emitting devices.

Example 11
<Comparison with Inorganic Phosphors>
A comparative experiment was conducted with the compound (1) and the inorganic phosphor CASN (CaAlSiN ₃ ; Eu ²⁺ , manufactured by Sialon).
A wavelength conversion composition of Example 11 (film-like Example 11) in the same manner as Example 1 except that the content of the compound (1) was changed to 2 parts by mass with respect to 100 parts by mass of the binder resin. The wavelength conversion member of
Also, in Example 1, a wavelength conversion composition was prepared in the same manner as Example 1, except that the compound (1) was replaced with CASN and the content was changed to 10 parts by mass with respect to 100 parts by mass of the binder resin. An object (a film-like wavelength conversion member) was produced.
About each wavelength conversion member produced in this way, the luminescence intensity in the wavelength region of 580-750 nm was measured and compared using a fluorescence spectrophotometer (Shimadzu Corporation). As a result, the wavelength conversion member of Example 11 using the compound (1) exhibited emission intensity twice or more that of the wavelength conversion member using the inorganic phosphor CASN.
From this result, it is understood that the amount of the compound (1) added can be reduced more than that of the inorganic phosphor when the content of the photoluminescent phosphor is adjusted to achieve the same emission intensity. Furthermore, since the content can be reduced, light scattering by particles of the compound (1) incident on the wavelength conversion composition can be reduced, and the effect of enhancing the light extraction efficiency from the wavelength conversion composition is also expected. I know what I can do.

  From the results of the above Examples 1 to 11, in the wavelength conversion composition containing the above compound (I) and the above binder resin, compound (I) can be dispersed in the solid state in the binder resin, and high quantum It shows the yield and the excellent durability. Such a wavelength conversion composition and a light emitting device using this wavelength conversion composition are disposed close to or in contact with the light source even if the compound (I) is dispersed in a solid state in the binder resin. Also for white LEDs and the like, red light can be emitted with a high quantum yield over a long period of time to emit the desired wavelength light. In addition, the wavelength conversion composition and the light emitting device of the present invention can be used in reduced amounts relative to the inorganic phosphor, and further, it can be expected that the light extraction efficiency can be enhanced.

Claims (10)

A wavelength conversion composition comprising a photoluminescent phosphor and a binder resin, which converts the wavelength of incident light into light of a longer wavelength,
The wavelength conversion composition whose at least 1 sort (s) of said photoluminescent fluorescent substance is a compound represented by the following general formula (I), and whose said binder resin is a silicone resin or an epoxy resin.

In the formula, Ar ¹ and Ar ² each independently represent an aryl group or a heteroaryl group, and R ¹ and R ² each independently represent an alkyl group, an alkylcarbonyl group, an alkenylcarbonyl group, an aryl group or a heteroaryl group. R ³ , R ⁴ , R ⁶ and R ⁷ each independently represent a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, an electron withdrawing group, or an aryl group substituted with an electron withdrawing group. However, any one of R ³ , R ⁴ , R ⁶ and R ⁷ is an electron withdrawing group or an aryl group substituted by the electron withdrawing group. R ⁵ and R ⁸ each independently represent a hydrogen atom, an alkyl group or an aryl group.   The light-emitting device provided with the light source and the wavelength conversion part which consists of a wavelength conversion composition of Claim 1 which converts the light light-emitted by this light source. The light emitting device according to claim 2, wherein the electron withdrawing group which can be taken as R ³ , R ⁴ , R ⁶ and R ⁷ in the general formula (I) is a cyano group, an alkoxycarbonyl group or a sulfo group. At least two of R ³ , R ⁴ , R ⁶ and R ^{7 in} the general formula (I) are a cyano group, an alkoxycarbonyl group, a sulfo group or an aryl group substituted with an electron-withdrawing group. Or the light-emitting device as described in 3. Wherein R ⁵ and R ⁸ in the general formula (I) are both light emitting device according to any one of claims 2 to 4 are hydrogen atoms. The light emission according to any one of claims 2 to 5, wherein each of R ⁴ and R ⁷ in the general formula (I) is an aryl group, a heteroaryl group or an aryl group substituted with an electron-withdrawing group. apparatus. The light emitting device according to any one of claims 2 to 6, wherein each of R ¹ and R ² in the general formula (I) is an aryl group or a heteroaryl group. The light emitting device according to any one of claims 2 to 7, wherein each of R ³ and R ⁶ in the general formula (I) is a cyano group or an alkoxycarbonyl group.   The light emitting device according to any one of claims 2 to 8, wherein the light source emits light having a wavelength of 350 nm to 480 nm.   The compound represented by the said general formula (I) absorbs the light emitted from the said light source, and exhibits the light emission in which a peak wavelength is observed in the area | region of 580 nm or more and 750 nm or less. The light emitting device according to claim 1.