JP7037145B2 - Luminescent body containing a fluorene compound - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Law 1. March 3, 2017 Announced on DVD 3PA-017 of the Proceedings of the 97th Annual Meeting of the Chemical Society of Japan (2017) published by the Chemical Society of Japan. March 18, 2017 Presented with a document (poster) at the PA venue (memorial hall) of the 97th Annual Meeting of the Chemical Society of Japan (2017), Keio University Hiyoshi Campus. May 15, 2017 Proceedings of the Society of Polymer Science, Japan, published by the Society of Polymer Science, Japan 66th (2017) Annual Meeting of the Society of Polymer Science, Vol. 66, No. 1, 1Pc071 4. May 29, 2017 Presented with a document (poster) at the 66th Annual Meeting of the Society of Polymer Science, Makuhari Messe International Exhibition Hall 8

The present invention relates to a luminescent material containing a specific fluorene compound as a light emitting material or a sensitizer (for example, a coating agent such as a paint or an ink composition, a photoelectric conversion element, etc.).

Ultraviolet light (ultraviolet or UV) with a wavelength of 400 nm or less is utilized in various fields such as sterilization, scientific analysis, resin curing, and light source of white light emitting diode (LED) by utilizing its characteristics such as high energy. .. Ultraviolet light is usually used in the form of a fluorescent tube, a mercury lamp, a backlight, or the like, and mercury is used as an ultraviolet light source. However, since mercury is harmful to the human body, the "Minamata Convention on Mercury" was adopted at the diplomatic conference held in Minamata City in 2013, and was concluded in 2016 in Japan as well. This Convention stipulates proper management and emission reduction of mercury mining, distribution, use and disposal for the purpose of protecting human health and the environment from the artificial emission and release of mercury and mercury compounds. Has been done. Since this treaty restricts the manufacture and trade of products that use mercury, there is a need for new materials that can emit ultraviolet light in place of mercury. Against this background, near-ultraviolet LEDs with a wavelength of 365 nm using gallium nitride (GaN) have already been put into practical use. However, when such an inorganic material is used, the preparation of the device tends to be complicated. Therefore, it is expected that an organic light emitting material that can be easily or efficiently produced by a method such as a coating method will be put into practical use.

As such an organic light emitting material, for example, polysilane having an organic functional group and the like are being studied. Japanese Patent Application Laid-Open No. 9-289337 (Patent Document 1) describes a thin film made of a polymer or oligomer in which the same or different elements selected from Si, Ge, Sn, and Pb are directly linked, and at least one of them is a transparent electrode. An ultraviolet region electroluminescence element arranged between two electrodes is disclosed. In this document, an EL element having polysilane or oligosilane such as polydi-n-hexylpolysilylene (PDHS) as a light emitting layer is prepared, and the EL element is cooled to 77K and measured in the emission spectrum. It is described that it has a strong peak in the region of 400 nm or less and the peak width is about 20 nm.

However, this document describes that a broad spectrum is observed, probably because polysilane has various conformations at room temperature, and ultraviolet light with a narrow peak width (or high monochromaticity) is emitted at room temperature. It cannot be obtained in the environment. Therefore, it is not easy to handle and its use is limited.

Japanese Patent Application Laid-Open No. 11-26159 (Patent Document 2) discloses a near-ultraviolet / ultraviolet wavelength band room temperature light emitting element having a light emitting layer formed of polysilane having a polydiphenylsilane skeleton. In Example 1 of this document, it is described that a thin film of polybis-pn-butylphenylsilane (PBPS) exhibits strong light emission near about 400 nm in the emission spectrum at room temperature.

However, this document does not specifically describe ultraviolet light having a wavelength shorter than 400 nm.

On the other hand, it is also considered to use a compound having a fluorene skeleton as an organic material. For example, in Japanese Patent Application Laid-Open No. 2004-527628 (Patent Document 3), a 9,9-diarylfluorene-2,7-diyl skeleton is used as a polymer used in an optical device having a hole transport region, an electron transport region, and a light emitting region. The polymer having the above is disclosed.

However, although it is described that the polymer emits light having a wavelength of 400 to 500 nm, this document does not specifically describe ultraviolet light having a wavelength shorter than 400 nm.

Japanese Patent Application Laid-Open No. 2006-256982 (Patent Document 4) discloses that a specific compound having three or more spirobifluorene skeletons has an ultraviolet organic electroluminescent ability having a maximum wavelength of 400 nm or less. In Example 1 of this document, it is described that a compound in which spirobifluorene is bonded is prepared at each of the 1, 3 and 5-positions of the benzene ring, and has an emission peak at 392 nm in the fluorescence spectrum.

However, such a light emitter cannot be used for applications that require ultraviolet light having a shorter wavelength. Further, since the emission peak is a broad peak, it is not possible to obtain highly monochromatic ultraviolet light.

As described above, since an organic material capable of emitting short-wavelength and highly monochromatic light has not yet been found, the formability of the light emitter (or device) while stably or efficiently emitting short-wavelength light (or device) ( Or productivity) is difficult to improve.

Japanese Unexamined Patent Publication No. 2009-96782 (Patent Document 5) discloses a fluorene derivative having a structure in which an aromatic hydrocarbon ring is bonded to the 9,9-position of the fluorene ring via an alkylidene group or an alkylene group. Has been done. Although it is described in this document that the fluorene derivative is excellent in various properties and can be used as a resin additive or as a raw material or an intermediate for pharmaceuticals, pesticides, etc., the light emitting property of the fluorene derivative is described. Nothing is mentioned.

JP-A-9-289337 (Claim 1, paragraphs [0026] to [0028], FIG. 3). JP-A-11-26159 (Claim 1, Example 1) JP-A-2004-527628 (Claims 1 and 9, paragraph [0013]) JP-A-2006-256982 (Claims, paragraph [0004], Example 1, FIG. 1) JP-A-2009-96782 (Claims, paragraphs [0062] to [0069])

Therefore, an object of the present invention is to provide a illuminant capable of emitting ultraviolet light having a shorter wavelength even when an organic material is used (for example, an organic illuminant, an organic-inorganic hybrid illuminant, etc.).

Another object of the present invention is to provide a light emitter capable of emitting ultraviolet light having high monochromaticity (or having a narrow peak width in the emission spectrum).

Still another object of the present invention is to provide a light emitter capable of emitting ultraviolet light having a short wavelength and high monochromaticity even in a room temperature environment.

Another object of the present invention is to provide a light emitting body capable of emitting brighter light with high light emission intensity (or brightness) even for a light emitting material having a large band gap and requiring high excitation energy (such as a blue light emitting material). It is in.

As a result of diligent studies to achieve the above-mentioned problems, the present inventors have found that, surprisingly, a specific fluorene compound can emit light having a shorter wavelength than that of a conventional organic material. Was completed.

That is, the luminescent material of the present invention contains a fluorene compound represented by the following formula (1).

(In the formula, X is the same or different hydrocarbon group which may have a hydrogen atom, a hydroxyl group, a carboxyl group, an alkoxycarbonyl group, an amino group, a substituted amino group, a halogen atom, or a substituent, R ¹ is The same or different substituents, k indicates the same or different integers from 0 to 4).

In the formula (1), X may be a hydrogen atom, an alkyl group or a group X ¹ , and the group X ¹ may be a group represented by the following formula (X1).

(In the formula, A is an alkylene group or an alkylidene group, m is 0 or 1, Z is an arene ring, R ² is a substituent, and n is an integer of 0 or more).

In the formula ( ¹ ), X may be a hydrogen atom, a C _1-6 alkyl group or a group X1. Further, in the formula (X1), the group X ¹ may be a C _1-6 alkylene group, Z may be a C _6-14 arene ring, and R ² is a C _1-6 alkyl group. , C _6-10 aryl group, hydroxyl group, hydroxy (mono to deca) C _2-4 alkoxy group or carboxyl group, and n may be an integer of about 0 to 5.

In the formula (1), X may be a C _1-4 alkyl group or a group X ¹ . Further, in the formula (X1), the group X ¹ may be a C _1-3 alkylene group, m may be 1, Z is a C _6-10 arene ring, and R ² is C _1- . It may be a ₄ -alkyl group, a C _6-10 aryl group, a hydroxyl group or a carboxyl group, and n may be an integer of about 0 to 3.

In the emission spectrum of the fluorene compound represented by the above formula (1) in the solid state, even if it contains at least one emission peak having a maximum wavelength of λ _{em and max} of about 300 to 400 nm and a half width of about 50 nm or less. good.

In the luminescent material, the fluorene compound represented by the formula (1) may be a light emitting material (first light emitting material); the fluorene compound is a sensitizer and a second light emitting material (for example, for example). (Blue luminescent material, etc.) may be further contained.

The luminescent material may be a coating agent (for example, a paint (or an ink (or ink) composition) or the like). The coating agent (luminous material) further contains a binder component (for example, at least one binder component selected from a (meth) acrylic resin, a styrene resin, a polycarbonate resin, and a silicon resin). May be good. Further, the present invention is also a method of irradiating a coating film (coating film) formed by applying the light emitting body with light and detecting the light emitted by the coating film by a detection device equipped with a spectroscope and a detector. Include.

The light emitter may be a photoelectric conversion element.

Since the illuminant of the present invention contains a specific fluorene compound, even though an organic material is used, light having a shorter wavelength (for example, near-ultraviolet light having a wavelength of about 300 to 400 nm, preferably a wavelength of 300 to 380 nm) is used. It can emit near-ultraviolet light (such as near-ultraviolet light). It is also possible to emit light having high monochromaticity (or having a narrow peak width in the emission spectrum). Moreover, the light emitter of the present invention can emit light having a short wavelength and high monochromaticity even in a room temperature environment. Further, in the light emitting body of the present invention, even if the light emitting material has a large band gap and requires high excitation energy (blue light emitting material, etc.), the specific fluorene compound absorbs it from the outside (light energy, electric energy, etc.). It can transfer (give or give) a high amount of energy and emit brighter light with high emission intensity (or brightness).

FIG. 1 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 1. FIG. 2 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 2. FIG. 3 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 3. FIG. 4 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 4. FIG. 5 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 5. FIG. 6 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 6. FIG. 7 is a measurement result of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 7. FIG. 8 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 8. FIG. 9 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 9. FIG. 10 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 10. FIG. 11 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 11. FIG. 12 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 12. FIG. 13 is a measurement result of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 13. FIG. 14 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 14. FIG. 15 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 15. FIG. 16 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 16. FIG. 17 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 17. FIG. 18 is an observation image of a surface and a cross section by a field emission scanning microscope (FE-SEM) of Example 17. FIG. 19 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 18. FIG. 20 is an observation image of a surface and a cross section by a field emission scanning microscope (FE-SEM) of Example 18. FIG. 21 is an observation image of a surface and a cross section by a field emission scanning microscope (FE-SEM) of Example 19. FIG. 22 shows the measurement results of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 20. FIG. 23 is a measurement result of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 21. FIG. 24 is a measurement result of the excitation spectrum (solid line) and the emission spectrum (dashed line) of Example 22. FIG. 25 shows the measurement results of the ¹³ C NMR spectra of the compound prepared in Synthesis Example 1. FIG. 26 shows the measurement results of the ¹³ C NMR spectra of the compound prepared in Synthesis Example 2.

[Fluorene compounds and their properties]
The luminescent material of the present invention contains at least a fluorene compound represented by the following formula (1).

(In the formula, X is the same or different hydrocarbon group which may have a hydrogen atom, a hydroxyl group, a carboxyl group, an alkoxycarbonyl group, an amino group, a substituted amino group, a halogen atom, or a substituent, R ¹ is The same or different substituents, k indicates the same or different integers from 0 to 4).

In the above formula (1), the substituent represented by R ¹ is, for example, a hydrocarbon group [for example, an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, t- Linear or branched C _1-6 alkyl group such as butyl group), aryl group (eg C _6-10 aryl group such as phenyl group), etc.], cyano group, halogen atom (eg fluorine atom) , Chlorine atom, bromine atom, etc.). Among these groups R ¹ , alkyl groups (for example, linear or branched C _1-4 alkyl groups), cyano groups and halogen atoms are preferable, and alkyl groups (particularly, C _1-3 such as methyl groups) are preferable. Alkyl group) is preferred.

The substitution number k of the group R ¹ may be, for example, an integer of about 0 to 3 (for example, 0 to 2), preferably 0 or 1, and more preferably 0. Further, the types of the groups ^R1 substituting for different benzene rings in the fluorene ring may be the same or different from each other, and when k is 2 or more, the types of the two or more groups ^R1 substituting for the same ring are , May be the same or different from each other. Further, the substitution position of the group ^R1 is not particularly limited, and may be, for example, 2-position to 7-position (2-position, 3-position, 7-position, etc.).

The group X includes a hydrogen atom, a hydroxyl group, a carboxyl group, an alkoxycarbonyl group (for example, a methoxycarbonyl group), an amino group, a substituted amino group (for example, a dialkylamino group such as a dimethylamino group, and a diacyl such as a diacetylamino group). Examples include an amino group), a halogen atom (eg, chlorine, bromine, iodine, etc.), a hydrocarbon group which may have a substituent, and the like. Among these groups X, in the coating agent described later, from the viewpoint of facilitating the formation of a uniform coating film, it is preferable that a group other than the hydrogen atom, that is, at least the 9-position of fluorene is substituted. From the viewpoint that it is difficult to inhibit (or absorb) the light emission of the fluorene compound, a hydrocarbon group which may have a substituent is preferable.

Examples of the hydrocarbon group include an alkyl group, a cycloalkyl group, an aryl group, and a group in which two or more of these hydrocarbon groups are combined (bonded).

Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-hexyl group, n-octyl group and 2-ethylhexyl. Linear or branched C _1-20 alkyl groups such as groups, n-decyl groups, n-dodecyl groups, preferably linear or branched C _1-12 alkyl groups, more preferably linear or branched. Examples thereof include a branched C _1-6 alkyl group.

Examples of the cycloalkyl group include a C _5-10 cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, preferably a C _5-8 cycloalkyl group and the like.

Examples of the aryl group include a C _6-14 aryl group such as a phenyl group, a naphthyl group (1-naphthyl group, 2-naphthyl group), a biphenylyl group, an anthryl group and a phenanthryl group, preferably a C _6-10 aryl group and the like. Can be mentioned.

The group in which two or more kinds of hydrocarbon groups are combined (bonded) is not particularly limited, and is, for example, a mono or di, such as an alkylaryl group (for example, a methylphenyl group (trill group), a dimethylphenyl group (kisilyl group)). C _1-6 alkyl C _6-10 aryl group, etc.), aralkyl group (eg, C _6-10 aryl C _1-6 alkyl group such as phenylmethyl group (benzyl group), 2-phenylethyl group (phenethyl group)) And so on.

Examples of the substituent of the hydrocarbon group include a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom); a hydroxyl group; an alkoxy group (for example, a methoxy group, an ethoxy group, a propoxy group and an n-butoxy). Linear or branched C _1-10 alkoxy groups such as groups, isobutoxy groups, s-butoxy groups, t-butoxy groups; cycloalkyloxy groups (eg, C _5-10 cycloalkyls such as cyclohexyloxy groups). Oxy group, etc.); Aryloxy group (eg, C _6-10 aryloxy group such as phenoxy group); Aralkyloxy group (eg, C _6-10 aryl-C _1-4 alkyloxy group such as benzyloxy group, etc.) ); Hydroxy (poly) alkoxy group [eg, hydroxy (poly) C _2-6 alkoxy group such as 2-hydroxyethoxy group, 2-hydroxypropoxy group, 2- (2-hydroxyethoxy) ethoxy group]; thiol group. Alkylthio groups (eg, C _1-10 alkylthio groups such as methylthio groups, ethylthio groups, propylthio groups, n-butylthio groups, t-butylthio groups); cycloalkylthio groups (eg, C _5-10 such as cyclohexylthio groups). Cycloalkylthio groups, etc.); arylthio groups (eg, C _6-10 arylthio groups such as thiophenoxy groups); Aralkylthio groups (eg, C _6-10aryl -C _1-4 alkylthio groups such as benzylthio groups); Acrylic groups (eg, C _1-6 acyl groups such as acetyl groups); carboxyl groups; alkoxycarbonyl groups (eg, C _1-6 alkoxy-carbonyls such as methoxycarbonyl groups); amino groups; substituted amino groups [eg, , Dialkylamino groups (eg, diC _1-4 alkylamino groups such as dimethylamino groups), diacylamino groups (eg, di (C _1-6 acyl) amino groups such as diacetylamino groups), etc.]; Cyano Group; Examples include a nitro group.

Substituents of these hydrocarbon groups can also be used alone or in combination of two or more. Of these substituents, a hydroxyl group, a hydroxy (poly) alkoxy group, a carboxyl group and the like are preferable. The substitution positions and the number of substitutions of these substituents are not particularly limited.

Typical examples of the hydrocarbon group which may have a substituent include an alkyl group and ^a group X1 represented by the following formula (X1).

(In the formula, A is an alkylene group or an alkylidene group, m is 0 or 1, Z is an arene ring, R ² is a substituent, and n is an integer of 0 or more).

In the formula (X1), the alkylene group represented by A is, for example, a linear group such as a methylene group, an ethylene group, a propylene group, a 1,3-propane-diyl group, or a 1,4-butane-diyl group. Examples thereof include a branched C _1-6 alkylene group, preferably a linear or branched C _1-4 alkylene group.

Examples of the alkylidene group represented by A include a linear or branched C _2-6 alkylidene group such as an ethylidene group, a propyridene group and a 2,2-propane-diyl group, preferably a linear or branched chain. The form C _2-4 alkylidene group and the like can be mentioned.

Of these groups A, an alkylene group is preferable, and a linear or branched _C1-3 alkylene group (for example, a methylene group, an ethylene group, particularly a methylene group) is preferable.

Although m may be either 0 or 1, it is preferably 1 from the viewpoint that ultraviolet light having a short wavelength and high monochromaticity can be easily obtained.

The arene ring (aromatic hydrocarbon ring) represented by Z is, for example, a monocyclic arene ring such as a benzene ring; a fused polycyclic arene ring such as a naphthalene ring (condensed polycyclic aromatic hydrocarbon ring). [For example, a fused dicyclic arene ring (for example, a fused dicyclic _C10-16 arene ring such as a naphthalene ring or an inden ring), a fused tricyclic arene ring (for example, an anthracene ring, a phenanthren ring, etc.) and the like. Two-to-four ring type arene ring, etc.]; Ring-assembled arene ring (ring-aggregated polycyclic aromatic hydrocarbon ring) [For example, beerlane ring such as biphenyl ring, phenylnaphthalene ring, binaphthyl ring, tellarene ring such as terphenyl ring Etc.] and so on. The preferred ring Z is a C _6-14 arene ring, more preferably a C _6-12 arene ring such as a benzene ring, a naphthalene ring, or a biphenyl ring (for example, a C 6-10 arene ring such as a benzene ring or a naphthalene ring, particularly a C _6-10 arene ring. Benzene ring) and the like. In the ring Z, the 9-position of the fluorene ring or the bonding position with the group A is not particularly limited.

As the substituent represented by R ² , the hydrocarbon group exemplified in the above-mentioned group X section (for example, an alkyl group, a cycloalkyl group, an aryl group, and two or more kinds of these hydrocarbon groups are combined (bonded)). ) Groups and the like); and the same groups as the groups exemplified as the substituents of this hydrocarbon group in the above-mentioned group X section can be mentioned. These groups R ² can also be used alone or in combination of two or more. Preferred groups ^R2 include an alkyl group (eg, a linear or branched C _1-6 alkyl group such as a methyl group), an aryl group (eg, a C _6-10 aryl group such as a phenyl group), and a hydroxyl group. , Hydroxy (poly) alkoxy group (for example, hydroxy (mono to deca) C _2-4 alkoxy group such as 2-hydroxyethoxy group), carboxyl group and the like, and among them, alkyl group (for example, methyl group and the like). C _1-4 alkyl group, etc.), hydroxyl group, carboxyl group, etc. are preferable.

The substitution number n may be selected according to the type of the ring Z, and may be selected from an integer of about 0 to 7 (for example, 0 to 5), for example, about 0 to 4 (for example, 0 to 3). It may be an integer of, preferably an integer of about 0 to 2 (for example, 0 or 1), or may be 0. When the number of substitutions n is 2 or more, the types of the groups R2 having ² or more may be the same or different from each other.

The substitution position of the group ^R2 is not particularly limited and may be selected depending on the type of the ring Z. When Z is a benzene ring, the substitution position of the group R2 is relative to the 9-position of the fluorene ring or the phenyl group bonded to the group A. , For example, 3-position, 4-position, 3,4-position, 3,5-position, 3,4,5-position, preferably 4-position, 3,4-position, and more preferably 4-position. There may be. For example, when Z is a naphthalene ring, the substitution position of the group ^R2 is, for example, the 1,5-position, with respect to the 1-naphthyl group or the 2-naphthyl group bonded to the 9-position or the group A of the fluorene ring. It is often replaced by the positional relationship of the 2,6-position, preferably the 2,6-position.

A typical group X ¹ is, for example, a group in which (X-1) m is 0 [for example, a C _6-10 aryl group such as a phenyl group, a 1-naphthyl group, or a 2-naphthyl group). Alkylaryl group (eg, mono or diC _1-4 alkylC _6-10aryl group such as p-tolyl group, 3,5-kisilyl group); arylaryl group (3-phenylphenyl group, 4-phenylphenyl) C _6-10 aryl C _6-10 aryl group such as group); hydroxyaryl group (4-hydroxyphenyl group, 6-hydroxy-2-naphthyl group, 5-hydroxy-1-naphthyl group and the like hydroxy C _6- ( ₁₀ aryl group, etc.); Hydroxy-alkylaryl group (4-hydroxy-3-methylphenyl group, 4-hydroxy-3,5-dimethylphenyl group, etc.) (mono or di) C _1-4 alkyl C _{6- 10} aryl group, etc.); Hydroxy-arylaryl group (hydroxy-C _{6-10aryl C, 6-10 aryl} group, etc., such as 4-hydroxy-3-phenylphenyl group); Hydroxy (poly) alkoxyaryl group (4- (poly) alkoxyaryl group, etc.) 2-Hydroxyethoxy) phenyl group, 6- (2-hydroxyethoxy) -2-naphthyl group, 5- (2-hydroxyethoxy) -1-naphthyl group, 4- (2- (2-hydroxyethoxy) ethoxy) phenyl Hydroxyl (mono to deca) C _2-4 alkoxy C _6-10 aryl groups such as groups); hydroxy (poly) alkoxy-alkylaryl groups (hydroxy such as 4- (2-hydroxyethoxy) -3-methylphenyl groups) (Mono-deca) C _2-4 alkoxy- (mono or di) C _1-4 alkyl C _6-10 aryl group, etc.); hydroxy (poly) alkoxy-arylaryl group (4- (2-hydroxyethoxy) -3 -Hydroxy (mono to deca) C _2-4 alkoxy-C _{6-10aryl C 6-10 aryl} group such as phenylphenyl group; Carboxaryl group (carboxyC _6-10aryl group such as 4-carboxyphenyl group) Etc.), etc.]; (X-2) A group in which m is 1 and A is a C _1-3 alkylene group (particularly a methylene group) corresponding to the group in which m is 0 as exemplified in (X-1) above. And so on.

Preferred groups X include a hydrogen atom, an alkyl group (such as a C _1-6 alkyl group such as a methyl group), and a group X ¹ [for example, (X-2) (m is 1, A is a C _1-3 alkylene group). (Especially a group that is a methylene group)], etc., among which C _1-4 alkyl group such as a methyl group, m is 1 in the formula (X1), A is a methylene group, and Z is a benzene ring. Groups are preferred, more preferably C _1-2 alkyl groups (particularly methyl groups), benzyl groups, C _1-4 alkyl-benzyl groups, carboxybenzyl groups, and in particular C _1-2 alkyl-benzyl groups (eg, for example. 4-Methylbenzyl group and the like), carboxybenzyl group (for example, 4-carboxybenzyl group and the like) are preferable.

Typical fluorene compounds represented by the formula (1) are, for example, fluorene, 9,9-dialkylfluorenes (eg, 9,9-diC _1-6 alkyl such as 9,9-dimethylfluorene). Fluorene and the like), 9,9-bisarylfluorenes, 9,9-bis (arylmethyl) fluorene and the like.

Examples of 9,9-bisarylfluorene include 9,9-bisarylfluorene [eg, 9,9-bisphenylfluorene, 9,9-bis (2-naphthyl) fluorene and the like, 9,9-bis C. _6-10 aryl fluorene, etc.]; 9,9-bis (alkylaryl) fluorene [eg, 9,9-bis (mono or diC _1-6 alkyl C, etc., 9,9-bis (4-methylphenyl) fluorene, etc.] _6-10 aryl) fluorene, etc.]; 9,9-bis (arylaryl) fluorene [eg, 9,9-bis (4-phenylphenyl) fluorene, etc. 9,9-bis (C _6-10 aryl C _6- ) ₁₀ aryl) fluorene, etc.]; 9,9-bis (hydroxyaryl) fluorene [eg, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (6-hydroxy-2-naphthyl) fluorene, 9 , 9-bis (5-hydroxy-1-naphthyl) fluorene, etc. 9,9-bis (hydroxy C _6-10aryl ) fluorene, etc.]; 9,9-bis (hydroxy-alkylaryl) fluorene [eg, 9, 9,9-bis (hydroxy-mono or diC _1-6 ) such as 9-bis (4-hydroxy-3-methylphenyl) fluorene, 9,9-bis (4-hydroxy-3,5-dimethylphenyl) fluorene, etc. Alkyl C _6-10 aryl) fluorene, etc.]; 9,9-bis (hydroxy-arylaryl) fluorene [eg, 9,9-bis (4-hydroxy-3-phenylphenyl) fluorene, etc. 9,9-bis (eg, 9,9-bis (hydroxy-3-phenylphenyl) fluorene, etc.] Hydroxy-C _6-10 aryl C _6-10 aryl) fluorene, etc.]; 9,9-bis [hydroxy (poly) alkoxyaryl] fluorene [eg, 9,9-bis [4- (2-hydroxyethoxy) phenyl] Fluolen, 9,9-bis [6- (2-hydroxyethoxy) -2-naphthyl] fluorene, 9,9-bis [5- (2-hydroxypropoxy) -1-naphthyl] fluorene, 9,9-bis [ 4- (2- (2-Hydroxyethoxy) ethoxy) phenyl] fluorene and the like 9,9-bis [hydroxy (mono to deca) C _2-4 alkoxy C _6-10aryl ] fluorene and the like]; 9,9-bis [Hydroxy (poly) alkoxy-alkylaryl] fluorene [eg, 9,9-bis [4- (2-hydroxyethoxy) -3-methylphenyl] fluorene] , 9,9-Bis [4- (2- (2-hydroxyethoxy) ethoxy) -3,5-dimethylphenyl] fluorene and the like 9,9-bis [hydroxy (mono to deca) C _2-4 alkoxy-mono Or di C _1-6 alkyl C _6-10aryl ] fluorene, etc.]; 9,9-bis [hydroxy (poly) alkoxy-arylaryl] fluorene [eg, 9,9-bis [4- (2-hydroxyethoxy)) -3-phenylphenyl] 9,9-bis such as fluorene [hydroxy (mono to deca) C _2-4 alkoxy-C _{6-10aryl C 6-10 aryl} ) fluorene, etc.]; 9,9-bis (carboxyaryl) ) Fluolene [for example, 9,9-bis (carboxy-C _6-10 aryl) fluorene such as 9,9-bis (4-carboxyphenyl) fluorene] and the like.

Examples of 9,9-bis (arylmethyl) fluorene include 9,9-bis (arylmethyl) fluorene [for example, 9,9-bis (phenylmethyl) fluorene such as _9,9 -bis (C6-bis). ₁₀ aryl-methyl) fluorene, etc.]; 9,9-bis (alkylarylmethyl) fluorene [eg, 9,9-bis [(4-methylphenyl) methyl] fluorene, etc., 9,9-bis [((mono or mono or) D) C _1-6 alkyl-C _6-10aryl ) methyl] fluorene, etc.]; 9,9-bis (carboxyarylmethyl) fluorene [eg, 9,9-bis [(4-carboxyphenyl) methyl] fluorene, etc. 9,9-Bis (carboxy C _6-10 aryl-methyl) fluorene, etc.] and the like.

These fluorene compounds represented by the formula (1) can be used alone or in combination of two or more. Preferred fluorene compounds represented by the formula (1) include, for example, 9,9-dialkylfluorenes (for example, 9,9-diC _1-6 alkylfluorene) and 9,9-bis (arylmethyl). Fluorenes [eg, 9,9-bis (C _6-10 aryl-methyl) fluorene, such as 9,9-bis (phenylmethyl) fluorene, 9,9-bis [((mono or di) C _1-6 alkyl) -C _6-10 aryl) fluorene] fluorene, 9,9-bis (carboxy C _6-10aryl -methyl) fluorene, etc.], among which 9,9-diC _1-4 alkylfluorene (especially 9, 9,9-diC _1-2 alkylfluorene such as 9-dimethylfluorene), 9,9-bis [((mono or di) C _1-4 alkyl-C _6-10aryl ) methyl] fluorene, 9, 9-Bis (carboxy C _6-10aryl -methyl) fluorene is preferred, especially 9,9-bis [((mono or di) _C1-2 alkyl-C _6-10aryl ) methyl] fluorene (especially 9, 9-bis [(4-methylphenyl) methyl] fluorene, etc. 9,9-bis [((mono or di) C _1-6 alkyl-phenyl) methyl] fluorene, etc.), 9,9-bis [(4-4-methylphenyl) methyl] fluorene, etc. 9,9-bis [(carboxyphenyl) methyl] fluorene such as carboxyphenyl) methyl] fluorene is preferable.

The compound represented by the formula (1) may be a commercially available product or may be prepared by a conventional method. Typically, as a conventional method, for example, the method described in Patent Document 5, that is, a fluorene anion is generated by a reaction between fluorenes and a base catalyst, and the fluorene anions and haloalkylarenes (for example, 4-bromo) are generated. Examples thereof include a method of preparing a compound in which the group X is the group X1 in the formula (1) and m is ¹ in the formula (X1) by reacting with methyltoluene or the like.

Surprisingly, the compound represented by the formula (1) exhibits short wavelength and highly monochromatic emission characteristics. Therefore, the compound represented by the above formula (1) has, for example, a maximum wavelength λ _{em, max} of 250 to 450 nm (for example, in the emission (fluorescence or phosphorescence) spectrum in a solid state at room temperature (for example, 25 ° C.)). For example, it may be selected from a wide range of about 300 to 400 nm, for example, 300 to 380 nm (for example, 305 to 370 nm), preferably 310 to 360 nm (for example, 310 to 350 nm), and more preferably 315 to 340 nm (for example). For example, it may contain at least one emission peak of about 320 to 330 nm).

Moreover, since the emission peak has a narrow half-value width, it can emit light having high monochromaticity. The half width can be selected from the range of, for example, about 50 nm or less (for example, 0.1 to 50 nm), for example, 45 nm or less (for example, 1 to 40 nm), preferably 35 nm or less (for example, 10 to 33 nm). More preferably, it may be about 15 to 30 nm (for example, 18 to 28 nm).

Further, the compound represented by the formula (1) has, for example, a maximum wavelength λ _{ex, max} of 200 to 400 nm (for example) in an excitation spectrum (or absorption spectrum) in a solid state at room temperature (for example, 25 ° C.). , 250 to 370 nm) may be selected from a wide range, for example, 270 to 350 nm (for example, 280 to 340 nm), preferably 290 to 330 nm (for example, 295 to 325 nm), and more preferably 300 to 320 nm (for example). , 305 to 315 nm) may contain at least one absorption peak.

Examples of the solid state include single crystals, polycrystals, and amorphous (amorphous), and are usually polycrystals.

The emission quantum efficiency of the compound represented by the formula (1) may be, for example, about 3 to 20% (for example, 5 to 10%).

In the present specification and claims, the emission spectrum (or fluorescence spectrum), the excitation spectrum (or absorption spectrum), and the emission quantum efficiency can be measured by the methods described in Examples described later.

The light emitting body of the present invention is a light emitting material (or a first light emitting material) in which (a) a fluorene compound represented by the above formula (1) is excited by external energy (for example, light energy, electric energy, etc.) to emit light. ) May be used; (b) at least a part of the energy absorbed from the external energy of the fluorene compound represented by the above formula (1) is transferred (added or donated) to another substance. It may be a light emitting body containing a light emitting material (or a second light emitting material) that functions as a sensitizer and can emit light by using this sensitizer. When the light emitting body is the above (b), at least a part of the fluorene compound represented by the above formula (1) contained in the light emitting body may function as a sensitizer, and some of the fluorene compounds are others. It may emit light without transferring energy to the substance of.

The light emitting material (second light emitting material) in the case of (b) may be a fluorescent material or a phosphorescent material, and the excited fluorene compound represented by the formula (1) (excited body or excited species) may be used. ) (The excitation energy (band gap) is lower than the energy that can be transferred from the excited body), and a conventional light emitting material can be used without particular limitation. As such a second light emitting material, for example, an organic metal complex {for example, a transition metal organic complex [for example, an iridium complex (for example, tris [2- (2,4-difluorophenyl) pyridinato] iridium (III) ( Ir (Fppy) ₃ ), Tris (2-phenylpyridinato) Iridium (III) (Ir (ppy) ₃ ), Tris (benzo [h] quinolinato) Iridium (III) (Ir (bzq) ₃ ), Tris ( 1-Phenylisoquinolinato) Iridium (III) (Ir (piq) ₃ ), Bis [2- (2,4-difluorophenyl) pyridinato] (Picorinato) Iridium (III) (FIrpic), Bis (2-phenylpyri) Zinato) (Acetylacetonato) Iridium (III) ((ppy) ₂ Ir (acac)), Bis [2- (benzo [b] thiophen-2-yl) -pyridinato] (acetylacetonato) Iridium (III) ((Btp) ₂ Ir (acac)), bis (benzo [h] quinolinato) (acetylacetonato) iridium (III) ((bzq) ₂ Ir (acac)), etc.); platinum complex (eg platinum (II)) Octaethylporphyrin (PtOEP), etc.); Renium complex; Osmium complex; Complex of 6th period element of periodic table such as gold complex; Zinc complex (eg, bis [2- (2-benzoxazolyl) phenolato] zinc (II) ) (Zn-PBO), etc.]; Light metal organic complex [eg, tris (8-quinolinolato) aluminum (III) (Alq ₃ ), bis (2-methyl-8-quinolinolato) (p-phenylphenolato) aluminum Aluminum such as (III) (BAlq ₂ ), Tris (4-methyl-8-quinolinolato) aluminum (III) (Almq ₃ ), Tris (5-hydroxy-benzo [f] quinolinato) aluminum (III) (Alph ₃ ) Complexes; bis [10-hydroxy-benzo [h] quinolinato] berylium complexes such as beryllium (II) (Bebq ₂ )]; rare earth metal organic complexes [eg, (1,10-phenanthroline) tris [4,4,4 -Europium complexes such as trifluoro-1- (2-thienyl) -1,3-butandionato] europium (III) (Eu (TTA) ₃ phen); placeodium complex; samarium complex; terbium complex [eg, tris (acetylacetate) Nato) Terbium (III) ( Tb (acac) ₃ ) or its hydrate, etc.]; Disprosium complex; Holmium complex; Elbium complex; Thurium complex, etc.], etc.}; p-tolyl-vinyl) biphenyl (DTVBi), 9,10-bis [4- (diphenylamino) styryl] anthracene (BSA-2), 4,4'-bis [2- (9-ethyl-3-carbazolyl) Vinyl] biphenyl (BCzVBi), 1,4-bis [4- (di-p-tolylamino) styryl] benzene, etc.}; Polycyclic aromatic hydrocarbons {eg, anthracene, diphenyltetracene (DPT), perylene, 2 , 5,8,11-Tetra-t-butylperylene (TBP), rubrene, etc.}; Kinacdrine derivative {eg, N, N'-dimethylquinacridone (DMQA), etc.}; 2-Il) -7- (diethylamino) fluorene (coumarin 6), etc.}; Dicyanomethylene {for example, 4- (dicyanomethylene) -2-methyl-6- [4- (dimethylamino) styryl] -4H-pyran (DCM), 4- (dicyanomethylene) -2-methyl-6- [2- (2,3,6,7-tetrahydro-1H, 5H-benzo [ij] quinolidine-9-yl) vinyl] -4H- Pyran (DCM2), etc.}; Polymer materials {eg, polyphenylene vinylene (PPV), polythiophene (eg, poly (3-hexylthiophene-2,5-diyl) (P3HT), etc.), polyfluorene (eg, poly (9)). , 9-Di-n-octylfluorene-2,7-diyl), etc.} and the like.

These second light emitting materials can also be used alone or in combination of two or more. From the viewpoint of easy energy transfer, it is preferable that the wavelength region of the light emitted by the fluorene compound and the absorption band (absorption wavelength region) of the second light emitting material overlap with each other. Materials (such as blue phosphorescent materials) are preferred, for example, tris [2- (2,4-difluorophenyl) pyridinato] iridium (III) (Ir (Fppy) ₃ ), bis [2- (2,4-difluorophenyl). ) Pyridinato] (picolinat) Iridium complexes such as iridium (III) (FIrpic) (particularly Ir (Fppy) ₃ ) and the like are preferable. Since the blue light emitting material usually has a large bandgap and requires high excitation energy, even if a conventional sensitizer is used, the amount of energy is small and cannot be received (excited) in many cases. However, in the present invention, probably because the fluorene compound represented by the above formula (1) can impart a high amount of energy, even a blue light emitting material can be easily sensitized, and the light emission intensity (or brightness) is higher. It is possible to form a luminous body that can emit bright light. Therefore, it is expected that the quality (or efficiency) of the photoelectric conversion element such as a blue light emitting diode is effectively improved.

The ratio of the second light emitting material may be appropriately selected depending on the type thereof, and is, for example, 0.1 to 1000 parts by weight (for example) with respect to 100 parts by weight of the fluorene compound represented by the formula (1). It can be selected from a wide range of about 1 to 500 parts by weight, for example, 3 to 300 parts by weight (for example, 5 to 100 parts by weight), preferably 8 to 80 parts by weight (for example, 10 to 50 parts by weight), and further. It may be preferably about 12 to 30 parts by weight (for example, 15 to 25 parts by weight).

The light emitter of the present invention can be used in various forms or applications, and may be, for example, a coating agent (for example, a paint or an ink composition, hereinafter may be simply referred to as a paint or an ink composition), and may be photoelectric. It may be a conversion element.

(Coating agent (paint or ink composition))
When the luminescent material of the present invention is a coating agent (for example, a paint or an ink composition), the coating agent is a fluorene compound represented by the above formula (1) (and, if necessary, a second luminescent material). ), Further may contain a binder component. As the binder component, for example, a conventional resin (or polymer compound) can be used, and for example, an olefin resin, a (meth) acrylic resin, a styrene resin, a vinyl resin (for example, a vinyl chloride resin, a vinyl alcohol type) can be used. Resin), fluororesin, polycarbonate resin, thermoplastic polyester resin (eg, polyalkylene allylate such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyallylate, liquid crystal polyester, etc.), polyamide resin (eg, polyamide 6). , Aliper polyamide such as polyamide 66, semi-aromatic polyamide such as polyamide 6T, polyamide MXD, etc.), polyacetal resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin (polysulfone, polyether sulfone, etc.), poly Etherketone resins (polyetherketone, polyetheretherketone, polyetherketone etherketone ketone, etc.), thermoplastic polyimide-based resins (polyetherimide-based resin, polyamideimide-based resin, etc.), thermoplastic elastomers, cellulose-based resins (polyetherimide-based resin, polyamideimide-based resin, etc.) Thermoplastic resins such as cellulose ester resins such as triacetyl cellulose, cellulose ether resins such as ethyl cellulose; epoxy resins, urethane resins, thermosetting polyester resins (alkyd resins, unsaturated polyester resins, diallyl phthalates, etc.) Resins, vinyl ester resins, etc.), phenolic resins, amino resins (eg, melamine resin, urea resin, guanamine resin, etc.), furan resins, thermosetting polyimide resins (eg, bismaleimide-based resins, bismaleimide triazine resins, etc.) , Thermosetting resin such as silicon resin, photocurable resin and the like. These resins can also be used alone or in combination of two or more. Among these binder components, (meth) acrylic resin and styrene resin from the viewpoint that the fluorene compound represented by the above formula (1) is difficult to absorb the ultraviolet light emitted and the fluorene compound is easily dispersed uniformly. , Polycarbonate-based resin and silicon-based resin are preferable.

Examples of the (meth) acrylic resin include (meth) acrylic monomers [for example, (meth) acrylic acid, (meth) acrylic acid C _1-18 alkyl ester, (meth) acrylic acid hydroxy C _2-18 alkyl, and the like. Glycidyl (meth) acrylate, (meth) acrylonitrile, etc.] alone or in a copolymer [eg, poly (meth) acrylic acid ester such as methyl poly (meth) acrylate, methyl methacrylate- (meth) acrylate copolymer. Combined, methyl methacrylate-acrylic acid ester- (meth) acrylic acid copolymer, methyl methacrylate- (meth) acrylic acid ester copolymer, etc.]; (meth) acrylic monomer and other copolymerizable singles. Examples thereof include a copolymer with a polymer (styrene-based monomer such as styrene and α-methylstyrene, maleic anhydride, etc.). Among these (meth) acrylic resins, poly (meth) acrylic acid C _1-8 alkyl esters such as polymethyl methacrylate are preferable.

Examples of the styrene-based resin include a styrene-based monomer (styrene, α-methylstyrene, vinyltoluene, etc.) alone or a copolymer [for example, polystyrene (atactic polystyrene, isotactic polystyrene (IPS), syndiotac). Tick Polystyrene (SPS), etc.), styrene-vinyltoluene copolymer, styrene-α-methylstyrene copolymer, etc.]; Copolymer of styrene-based monomer and copolymerizable monomer [for example, styrene- Acrylonitrile copolymer (AS resin), styrene- (meth) acrylic acid copolymer, styrene- (meth) acrylic acid ester copolymer (MS resin, etc.), styrene-maleic anhydride copolymer, styrene-phenylmaleimide Copolymers, styrene-butadiene block copolymers, styrene-butadiene-styrene block copolymers, etc.]; Impact-resistant styrene-based resins (graft copolymers with rubber components and / or blends (mixtures)) [for example. , Impact resistant polystyrene (HIPS); Acrylonitrile-butadiene-styrene copolymer (ABS resin); Instead of the ABS resin butadiene rubber B, acrylic rubber A, chlorinated polyethylene C, ethylene propylene rubber (or ethylene propylene diene) AXS resin (AAS resin, ACS resin, AES resin, etc.) using a rubber component such as (rubber) E; (meth) acrylic acid ester-butadiene-styrene copolymer (for example, methyl methacrylate-butadiene-styrene copolymer). (MBS resin), etc.), etc.] and the like. Among these styrene-based resins, styrene-based monomers alone or copolymers (particularly homopolymers) are preferable.

Examples of the polycarbonate-based resin include aromatic polycarbonate resins such as bisphenol-type polycarbonate resins containing bisphenols as polymerization components (for example, bisphenol A-type polycarbonate resin, bisphenol F-type polycarbonate resin, etc.).

Examples of bisphenols include bis (hydroxyaryl) alkanes [for example, bis (4-hydroxyphenyl) methane (bisphenol F), 1,1-bis (4-hydroxyphenyl) ethane (bisphenol AD), 2,2. -Bis (4-hydroxyphenyl) propane (bisphenol A), 1,1-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) butane (bisphenol B), 2,2-bis ( 4-Hydroxyphenyl) -3-methylbutane, 2,2-bis (4-hydroxy-3-phenylphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane (bisphenol C), 2, 2-Bis (4-hydroxy-3-isopropylphenyl) propane (bisphenol G), etc.]; Bis (hydroxyaryl) -arylalkanes [for example, 1,1-bis (4-hydroxyphenyl) -1-phenylethane (for example) Bisphenol AP), bis (4-hydroxyphenyl) -diphenylmethane (bisphenol BP), etc.]; Bis (hydroxyaryl) cycloalkans [eg, 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4-Hydroxyphenyl) cyclohexane (bisphenol Z), 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane (bisphenol TMC), etc.]; Bis (hydroxyaryl) ethers [eg, bis (4-Hydroxyphenyl) ether, etc.]; Bis (hydroxyaryl) ketones [eg, bis (4-hydroxyphenyl) ketone, etc.]; Bis (hydroxyaryl) sulfides [eg, bis (4-hydroxyphenyl) sulfide, etc.] ]; Bis (hydroxyaryl) sulfoxides [eg, bis (4-hydroxyphenyl) sulfoxide, etc.]; Bis (hydroxyaryl) sulfones [eg, bis (4-hydroxyphenyl) sulfone (bisphenol S), etc.]; Biphenols [For example, o, o'-biphenol, m, m'-biphenol, p, p'-biphenol, etc.] and the like can be mentioned. These bisphenols can also be used alone or in combination of two or more.

Among these polycarbonate-based resins, a bisphenol-type polycarbonate resin containing bis (hydroxyaryl) alkanes (for example, bisphenol A) as a polymerization component is preferable.

In a silicon-based resin, the polyorganosiloxane (silicone) skeleton has a monofunctional M unit (generally represented by R ₃ SiO _1/2 ) and a bifunctional D unit (generally R ₂ SiO). Unit represented by _2/2 ), trifunctional T unit (generally represented by RSiO _3/2 ), and tetrafunctional Q unit (generally represented by SiO _4/2 ). It may contain at least one unit selected from the group consisting of units).

The group R in the formulas representing the M unit, the D unit and the T unit is a substituent. Examples of the substituent include an alkyl group, an aryl group, a cycloalkyl group, a vinyl group and the like. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, a t-butyl group, an n-hexyl group and an n-octyl group, 2 Examples thereof include C _1-12 alkyl groups such as an ethylhexyl group and an n-decyl group. Examples of the aryl group include a _C6-14 aryl group such as a phenyl group, a methylphenyl group (tolyl group), a dimethylphenyl group (chysilyl group), a biphenylyl group, and a naphthyl group. Examples of the cycloalkyl group include a C _5-10 cycloalkyl group such as a cyclopentyl group, a cyclohexyl group and a methylcyclohexyl group. These substituents can be used alone or in combination of two or more. Of these substituents, a C _1-4 alkyl group such as a methyl group and a C _6-12 aryl group such as a phenyl group are preferable, and they are difficult to absorb ultraviolet light and easily disperse the fluorene compound uniformly. A C _6-10 aryl group such as a phenyl group is particularly preferred.

Examples of the terminal group (group bonded to the terminal silicon (Si) atom) include a hydroxyl group and an alkoxy group (for example, a C _1-4 alkoxy group such as a methoxy group and an ethoxy group, preferably C _1-2 . Alkoxy groups, etc.), halogen atoms (chlorine, etc.), etc. may be mentioned. These end groups can also be used alone or in combination of two or more. Of these terminal groups, there are usually many cases such as a hydroxyl group and a C _1-2 alkoxy group.

The silicon-based resin preferably contains at least one unit selected from the above T units and Q units from the viewpoint of easily forming a coating film, and particularly preferably contains T units. The proportion of T units in the entire silicon-based resin is, for example, 50 mol% or more (for example, 60 to 100 mol%), preferably 70 mol% or more (for example, 80 to 99.9 mol%), and more preferably 90 mol. It may be% or more (for example, 95 mol% or more), or it may be silsesquioxane (or polysilsesquioxane) which is substantially 100 mol%.

The silsesquioxane (or polysilsesquioxane) may be ladder-shaped (ladder-shaped) or cage-shaped (cage-shaped), but it has a three-dimensional network shape (network) because it is easy to form a coating film. It is preferably in the form of a shape or a random structure). Examples of such silsesquioxane include polyalkylsilsesquioxane (for example, polymethylsilsesquioxane and the like) formed of T units (alkyl silsesquioxane units) in which R is an alkyl group. C _1-4 Alkyl sulceskioxane, etc.); Polyaryl sul sesquioxane (poly phenyl sul sesquioxane, etc., poly C ₆ ) formed of T units (aryl sill sesquioxane units) in which R is an aryl group. _-12 arylsilsesquioxane, etc.); Polysilsesquioxane formed by T units in which R is an alkyl group and T units in which R is an aryl group can be mentioned. These silsesquioxane can also be used alone or in combination of two or more. Of these silsesquioxane, polyarylsilsesquioxane formed in units of T in which R is an aryl group is preferable, and among them, poly-C _6-10 aryl silsesquioxane such as polyphenyl silsesquioxane is preferable. Sun is preferred.

Among these binder components, silicon-based resins (particularly silsesquioxane) are difficult to deteriorate (or decompose) even when exposed to ultraviolet light due to excitation light or light emission, and are excellent in thermal stability and heat dissipation. preferable. A silicon-based resin (particularly silsesquioxane) has a total light transmittance of, for example, 85% or more (particularly, because it interacts with a fluorene compound (particularly, a fluorene compound having a substituent at the 9-position)). For example, the haze value is as high as about 90% or more, and the haze value is as low as, for example, about 3% or less (for example, 1% or less), and it seems that it is easy to form a coating film in which the fluorene compound is uniformly dispersed.

The ratio of the binder component to the total solid content is, for example, 10 to 99.9% by weight (for example, 20 to 99% by weight), preferably 30 to 98% by weight (for example, 40 to 97% by weight), and further. It may be preferably about 50 to 95% by weight (for example, 60 to 93% by weight).

Further, the coating agent may further contain a solvent in order to adjust the viscosity and improve the coatability (or handleability), or may be dried and removed from the coating film after coating. Examples of the solvent include hydrocarbons (for example, aliphatic hydrocarbons such as hexane, alicyclic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as toluene and xylene, etc.); halogenated hydrocarbons (for example). For example, dichloromethane, chloroform, 1,2-dichloroethane, chlorobenzene, etc.; alcohols (eg, methanol, ethanol, 1-propanol, 2-propanol, n-butanol, isobutanol, s-butanol, t-butanol, etc. C _1-6 alkanol, etc.); Glycols (eg, (poly) C _2-4 alkylene glycol such as ethylene glycol, propylene glycol, diethylene glycol, etc.); Ethers (eg, chain ethers such as diethyl ether, tetrahydrofuran, 1 , Cyclic ethers such as 4-dioxane, etc.); Glycol ethers [eg, cellosolves (eg, C _1-4 alkyl cellosolves such as methyl cellosolve, ethyl cellosolve, etc.), carbitols (eg, methyl carbitol, ethyl, etc.) C _1-4 alkyl carbitol such as carbitol), (poly) C _2-4 alkylene glycol mono C _1-4 alkyl ether such as triethylene glycol monomethyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether; ethylene (Poly) C _2-4 alkylene glycol diC _1-4 alkyl ethers such as glycol dimethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether]; Glycol ether acetates [eg, cellosolve acetates (eg, methyl cellosolve) C _1-4 alkyl cellosolve acetate such as acetate), carbitol acetates (eg C _1-4 alkyl carbitol acetate such as methyl carbitol acetate), propylene glycol monomethyl ether acetate, dipropylene glycol monobutyl ether acetate, etc. (Poly) C _2-4 alkylene glycol mono C _1-4 alkyl ether acetate, etc.]; Ketones (eg, chain ketones such as acetone, methyl ethyl ketone, cyclic ketones such as cyclohexanone, etc.); Acetic acid, propionic acid, etc.); Ethers (eg, , Acetate esters such as methyl acetate, ethyl acetate, butyl acetate, lactic acid esters such as methyl lactate, etc.); Carbonates (eg, chain carbonates such as dimethyl carbonate, cyclic carbonates such as propylene carbonate, etc.); Nitriles ( For example, acetonitrile, propionitrile, benzonitrile, etc.); Amidos (eg, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, etc.); Sulfoxides (eg, dimethyl sulfoxide, etc.) ); Water; and a mixed solvent thereof and the like.

The ratio of the solvent can be appropriately selected depending on the viscosity of the coating agent and the like, and is not particularly limited. The solid content concentration of the coating agent may be, for example, 0.1 to 50% by weight, preferably 1 to 30% by weight, and more preferably about 3 to 20% by weight.

The coating agent may contain conventional additives. Conventional additives include, for example, dyes, pigments, pigment dispersants, wetting agents, thickeners, coupling agents, defoaming agents, anti-settling agents, anti-skinning agents, antioxidants, polymerization initiators, and curing agents. , Leveling agents, thixotropic agents, color separation inhibitors, matting agents, flame retardants, stabilizers (eg antioxidants, UV absorbers, light stabilizers, ozone degradation inhibitors, etc.), plasticizers, softeners, It may contain a lubricant, a mold release agent, an antistatic agent and the like.

Since the additive may absorb the excitation light for exciting the light emitting material (the fluorene compound or the second light emitting material) or the light emitted by the excited light emitting material, the coating agent is substantially an additive. It is not necessary to include. In particular, when the luminescent material is a coating agent using the fluorene compound as a light emitting material, it does not contain additives [composed of only the fluorene compound and a binder component (and a solvent if necessary)]. preferable.

The light emitting characteristics of the coating agent (or the coating film (coating film) formed by using the coating agent) are appropriately adjusted according to the type and concentration of the fluorene compound, the binder component, and if necessary, the second light emitting material. You may. When the second light emitting material is not used (when the fluorene compound is made to emit light without acting as a sensitizer), it is observed in the excitation spectrum and the light emission spectrum of the coating agent (or the coating film) at room temperature (for example, 25 ° C.). The absorption peak and emission peak to be generated shift to a slightly shorter wavelength side, for example, about 1 to 20 nm (for example, 2 to 10 nm), as compared with the absorption peak and emission peak of the fluorene compound in the solid state described above. In many cases, the half-price width of the emission peak seems to be slightly wider, for example, about 3 to 30 nm (for example, 5 to 20 nm) larger than the half-price width of the fluorene compound in the solid state described above. .. Further, probably because the fluorene compound is easily dispersed uniformly in the coating film and the concentration quenching can be effectively suppressed, the emission quantum efficiency is high, for example, it is often about 10 to 30% (for example, 15 to 25%). It seems.

Such coating agents may be, for example, invisible ink [for example, security ink (or security marker) for the purpose of identifying counterfeit products and preventing forgery of documents (banknotes, cash vouchers, warranty cards, etc.)]. good. Invisible ink is often a fluorescent substance that emits visible light when irradiated with ultraviolet light. Normally, such ink is colorless and cannot be visually recognized even if it is printed, and ultraviolet light is emitted by black light or the like. It can be visualized only by irradiating it. However, in recent years, black light is commercially available as a toy and is easily available, and can be easily visualized by a third party. Therefore, there is a concern that the security (confidentiality) of the information given by the invisible ink may be reduced. .. Therefore, from the viewpoint of improving security, the coating agent of the present invention preferably contains the fluorene compound represented by the formula (1) as a light emitting material.

Specifically, the wavelength of the ultraviolet light emitted by a general-purpose black light is about 365 nm, and the fluorene compound cannot be excited and does not emit light unless the ultraviolet light has a shorter wavelength. Even if the fluorene compound can emit light, it is difficult for a third party to even determine whether or not the invisible ink is applied because the emitted light is not visible light and cannot be visually recognized without using a detection device. Therefore, the security can be effectively improved.

Therefore, in the present invention, the coating film containing the illuminant (or the coating film formed by applying the illuminant and removing the solvent as needed) is irradiated with light, and the coating film emits light. It also includes a method of detecting light by a detector equipped with a spectroscope and a detector.

The coating film may be formed by applying a coating agent, and may be formed by using a conventional coating method, for example, a spin coating method, a gravure printing method, a screen printing method, an inkjet printing method, or the like.

As a light source used for detection, for example, compared to ultraviolet light having a shorter wavelength than ultraviolet light emitted by general-purpose black light [detection wavelength (wavelength of emission peak in solid state at room temperature of the fluorene compound), for example. A light source capable of irradiating ultraviolet light having a short wavelength of 10 nm or more, preferably 20 nm or more, specifically, ultraviolet light having a wavelength of, for example, 250 to 350 nm, preferably about 270 to 300 nm], for example, a xenon lamp, a heavy hydrogen lamp, or ultraviolet light. Examples thereof include a light fluorescent lamp (UV fluorescent lamp) and an ultraviolet light emitting diode (UVLED).

The detection device may be provided with at least a specific spectroscope and a detector, and may also be provided with the light source. Examples of the spectroscope include a spectroscope that can separate the light of a light source from the light emitted by a coating agent or a coating film, such as a diffraction grating, a prism, and an optical cut filter. Examples of the detector include a detector capable of detecting light emission (ultraviolet light of about 300 to 380 nm) of a coating agent or a coating film, for example, a photomultiplier tube, a photodiode, a CCD (Charge Coupled Device) sensor and the like. As such a detection device, a commercially available spectrofluorometer or the like may be used.

The invisible ink may be printed or applied to printed matter in various forms such as characters (or sentences) and figures (or patterns), and may be in the form of a barcode, QR (Quick Response) code (registered trademark), or the like. A lot of information may be given by applying to. Further, more information may be given by combining the plurality of the fluorene compounds. Specifically, since the fluorene compound has a small half-value width of the maximum emission peak in the emission spectrum, even if the illuminant contains a plurality of fluorene compounds, the emission peaks are less likely to overlap and can be easily detected as separate peaks. Therefore, more information is given by using not only the presence or absence of emission peaks due to a single fluorene compound but also the intensity ratio of a plurality of emission peaks obtained by adjusting the ratio of a plurality of fluorene compounds as a signal. You may.

(Photoelectric conversion element)
Typical examples of the photoelectric conversion element include a current injection type light emitting device [for example, an inorganic light emitting diode (LED), an organic EL element (or an organic light emitting diode (OLED)), etc.], and usually an organic EL element. In many cases. The current injection type light emission (for example, an organic EL element) is formed of an anode (transparent electrode) and a cathode (metal electrode), and an organic layer (organic thin film) or an organic-inorganic hybrid layer interposed between the electrodes. As a typical configuration, each layer is often formed in the order of transparent substrate / anode (anode) / hole (hole) transport layer / light emitting layer / electron transport layer / cathode (cathode). When the light emitting layer has a function as a hole transport layer or an electron transport layer, the hole transport layer or the electron transport layer is not always necessary.

Examples of the transparent substrate include a substrate made of an inorganic material such as glass; a (meth) acrylic resin (such as the (meth) acrylic resin exemplified in the coating agent section), and a styrene resin (of the coating agent). It is formed of an organic material such as a styrene resin exemplified in the above section), a polycarbonate resin (such as the polycarbonate resin exemplified in the coating agent section), and a polyester resin (a polyalkylene allylate resin such as polyethylene terephthalate). Examples include plastic boards. Further, the substrate may be in the form of a plate, but may be in the form of a sheet or a film.

As the anode, a transparent electrode is usually used, and it is often formed of a conductive metal oxide such as ITO (Indium Tin Oxide), FTO (Fluorine-doped Tin Oxide), and ZnO (Zinc Oxide). In the present specification and claims, the "transparent electrode" means an electrode capable of transmitting visible light and / or ultraviolet light. Therefore, when the fluorene compound represented by the above formula (1) is used as the light emitting material in the light emitting layer, the anode can transmit at least a part of the ultraviolet light emitted by the fluorene compound. Such an anode may be manufactured, for example, by reducing the thickness or by making a slit. Further, when the fluorene compound represented by the above formula (1) is used as a sensitizer for the second light emitting material, the anode does not necessarily have to transmit ultraviolet light.

Examples of the hole transport material forming the hole transport layer include aromatic amines [for example, 4,4'-bis (trilphenylamino) biphenyl (TPD), 4,4'-bis (α-). Naftyl-Phenylamino) Biphenyl (α-NPD), 1,1-bis [4- (trilphenylamino) phenyl] cyclohexane (TAPC), Tris [4- (trilphenylamino) phenyl] amine (m-TDATA), Tris [4- (9-carbazolyl) phenyl] amine (TCTA), etc.], phthalocyanins (eg, copper phthalocyanine, etc.), conductive polymers [eg, poly (3,4-ethylenedioxythiophene): polystyrene sulfone. Polythiophenes such as acid complex (PEDOT: PSS)] and the like. These hole transport materials can also be used alone or in combination of two or more. Of these, conductive polymers such as PEDOT: PSS are often used.

The light emitting layer contains at least the fluorene compound represented by the formula (1), and may contain the second light emitting material, if necessary. These luminescent materials (or sensitizers) may be used alone or in combination of two or more. The light emitting layer may be composed of only a light emitting material (and a sensitizer), may use the light emitting material as a guest material (or a dopant), and may further contain a host material. Examples of the host material include biphenyls such as 4,4'-bis (2,2-diphenylvinyl) biphenyl (DPvBi) and 4,4'-bis (9-carbazolyl) biphenyl (CBP), and coating agents. Examples thereof include binder components [for example, (meth) acrylic resin such as polymethyl methacrylate, polycarbonate resin such as bisphenol type polycarbonate, silicon resin such as polysilsesquioxane, etc.] and the like.

Examples of the electron transporting material forming the electron transporting layer include the aluminum complex (Alq ₃ and the like), the berylium complex (Bebq ₂ and the like) and the bisstyryl allene derivative (DTVBi and the like) described in the second light emitting material; Azole derivatives [eg 2- (4-t-butylphenyl) -5- (4-biphenylyl) -1,3,4-oxadiazole (t-Bu-PBD), 1,3-bis [5-( 4-t-butylphenyl) -1,3,4-oxadiazole-2-yl] benzene (OXD-7), etc.]; Triazole derivative [eg, 3- (biphenyl-4-yl) -5- (4) -T-butylphenyl) -4-phenyl-4H-1,2,4-triazole (TAZ), etc.]; Phenantroline derivatives [eg, 4,7-diphenyl-1,10-phenanthroline (BPhen), 4,7- Diphenyl-2,9-dimethyl-1,10-phenanthroline (BCP), etc.]; Sirol derivatives [eg, 1,1-dimethyl-3,4-diphenyl-2.5-di (2,2'-bipyridylou 3-) Il) Syrole, etc.] and so on. These electron transport materials can also be used alone or in combination of two or more.

The cathode (metal electrode) is often formed of, for example, a simple substance of a metal such as aluminum (Al), magnesium (Mg), or silver (Ag), or an alloy thereof.

An anode buffer layer (hole injection layer) [for example, a copper phthalocyanine thin film] may be formed between the anode and the hole transport layer, and a cathode buffer may be formed between the cathode and the electron transport layer. Even if a layer (electron injection layer) [for example, an inorganic thin film such as a lithium fluoride (LiF) thin film, a lithium oxide (Li ₂ O) thin film, an organic thin film doped with a metal such as lithium (Li), etc.] is formed. good.

The thickness of each layer (organic phase) interposed between the anode and the cathode may be, for example, about 0.1 to 500 nm (for example, 1 to 200 nm), and the thickness of the entire organic phase is about 1 μm or less. May be good.

Such an organic EL element may be used as a light source for visible light for display applications, and as a light source for ultraviolet light (UV lamp), for example, for sterilization applications, analytical applications, light sources for high color rendering white LEDs, and the like. It may be used for the purpose of.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. The evaluation method is shown below.

[Evaluation methods]
(Light emission characteristics)
Excitation spectrum and emission (fluorescence or emission) of a sample using a spectral fluorescence photometer (“F-4500” manufactured by Hitachi High-Technologies Co., Ltd., light source: xenon lamp, detector: photoelectron multiplying tube, spectroscope: diffraction grid) The phosphorescent spectrum was measured at room temperature (for example, 25 ° C.), and the half-value widths of the maximum wavelengths λ _{ex, max} of the excitation spectrum and the maximum wavelengths λ _{em, max} and λ _{em, max} of the emission spectrum were determined.

(X-ray structure analysis)
X-ray diffractometer (“RAXIS RapidII” manufactured by Rigaku Co., Ltd., X-ray source: MoKα ray generated from Mo tube is monochromated with a graphite monochromator and irradiated using a 0.5 mmφ collimator, detector: 2 The single crystal sample was fixed to the glass capillary with an adhesive using a dimensional curvature imaging plate and a sample holding table (1/4 χ (kai) goniometer), and then attached to the goniometer and attached to the goniometer. After observing the diffraction image generated by irradiating the sample with X-rays on an imaging plate, they were aggregated and used for analysis. The attached software "Crystal Structure" was used for structural analysis, and structural optimization was performed to determine the molecular structure in the crystalline state.

(Total light transmittance and haze value (haze value or haze))
Extraviolet visible near-infrared spectrophotometer ("V-780" manufactured by JASCO Corporation) equipped with an integrating sphere unit ("ISN-901i" manufactured by JASCO Corporation), light source: deuterium lamp and halogen lamp, detection A thin film sample was placed at the entrance of the light source of the integrating sphere using a photoelectron multiplying tube and a spectroscope (diffraction lattice) for measurement. According to the attached haze value calculation program "VWHZ-965", the total light transmittance and the sample scattering rate in the wavelength range of 380 to 780 nm (visible region) were measured, and the haze value was calculated based on them.

(Observation with field emission scanning electron microscope (FE-SEM))
Using a field emission scanning electron microscope (“JSM-6700F” manufactured by JEOL Ltd.), the sample was fixed to a sample table tilted at 60 degrees with a conductive tape and observed from above. The sample was observed at an acceleration voltage of 5 KV and a magnification of 40,000 to 45,000 times, and image data was obtained.

(Emission quantum efficiency)
Fluorescence spectrophotometer ("FP-6500" manufactured by Nippon Spectroscopy Co., Ltd., light source: xenon lamp, detector: photoelectron increase) equipped with a fluorescence integrating sphere unit ("ILF-533" manufactured by Nippon Spectroscopy Co., Ltd., diameter 100 mmφ) The double tube, spectroscope: diffraction grid) is spectrally corrected by the device function obtained using the attached standard light source for calibration, and the spectral area and the number of photons are made proportional to each other, and then the emission quantum efficiency is determined by the absolute method. Calculated. The excitation light is measured without the sample installed to determine the spectral area of the excitation light to be irradiated, and then the excitation light is measured with the sample installed to determine the spectral area of the irradiation excitation light not absorbed by the sample. By obtaining these differences, the number of photons absorbed in the sample was calculated. At the same time, the emission spectrum of the sample was also observed, and the number of photons emitted was calculated from the spectrum area. The emission quantum efficiency was calculated from the number of emitted photons with respect to the number of last absorbed photons.

<Emission characteristics of fluorene compounds>
[Synthesis Example 1] Synthesis of 9,9-bis (p-methylbenzyl) fluorene (BMBF) Fluorene (1.66 g, 10.0 mmol) and tert-BuOK (3) were placed in a 300 mL 4-port eggplant flask under an argon air flow. .36 g, 30.0 mmol, 3eq.) And DMSO (70 mL) were added and heated to 50 ° C. After 10 minutes, 4-methylbenzyl bromide (4.44 g, 24.0 mmol, 2.4 eq.) Was added in 0.74 g portions every 10 minutes. After the addition was completed, the mixture was heated and stirred at 60 ° C. for 19 hours. After returning to room temperature, it was put into ice water (500 mL) and diethyl ether (250 mL) was added. After separating the organic layer, the mixture was extracted with diethyl ether (150 mL × 2), the organic layers were combined, and the mixture was washed with brine (150 mL). After drying with magnesium sulfate, the solvent was distilled off to obtain a yellowish brown oil (4.32 g). Purification by silica gel chromatography (eluting solvent: hexane) gave a pale yellow solid (yield 2.25 g, yield 60.2%). ¹³ C NMR confirmed that it was 9,9-bis (p-methylbenzyl) fluorene (BMBF) [a compound represented by the following formula (1a)]. The ¹³ C NMR spectrum is shown in FIG.

¹³ C NMR (270 MHz, CDCl ₃ ): δ (ppm) 2.13 (s, 6H), 3.30 (s, 4H), 6.56 (d, 4H), 6.73 (d, 4H), 7.14-7.44 (m, 8H).

[Example 1]
The excitation spectrum and emission spectrum of BMBF prepared in Synthesis Example 1 in the solid state were measured. When irradiated with light of 200 to 300 nm, BMBF emitted ultraviolet light having a peak in the vicinity of 322 nm and having a half-value width of about 20 nm. The emission quantum efficiency was 7.6%. The results are shown in Table 1 and FIG.

[Synthesis Example 2] Synthesis of 9,9-bis (p-carboxybenzyl) fluorene (BCBF) Fluorene (1.66 g, 10.0 mmol) and tert-BuOK (6) were placed in a 200 mL 4-port eggplant flask under an argon air flow. .73 g, 60.0 mmol, 6eq.), DMSO (70 mL) was added and heated to 50 ° C. After raising the temperature to 50 ° C., 4-bromomethylbenzoic acid (5.16 g, 24.0 mmol, 2.4 eq.) Was added. After the addition was completed, the temperature was raised to 60 ° C. and the mixture was heated and stirred for 20 hours. After completion of heating and stirring, purification was performed by silica gel chromatography (eluting solvent: CHCl ₃ / MeOH = 20/1) to obtain a pale yellow powder (1.32 g). This was washed with a small amount of tetrahydrofuran (THF) to obtain a white powder (yield 0.45 g, yield 10.4%). ¹³ C NMR confirmed that 9,9-bis (p-carboxybenzyl) fluorene (BCBF) [a compound represented by the following formula (1b)] was present. The ¹³ C NMR spectrum is shown in FIG.

¹³ C NMR (270 MHz, DMSO-d ₆ ): δ (ppm) 3.57 (s, 4H), 6.62 (d, 4H), 7.10-7.22 (m, 10H), 7.80 (D, 2H), 12.70 (s, 2H).

[Example 2]
The excitation spectrum and emission spectrum of BCBF prepared in Synthesis Example 2 in the solid state were measured. When the BCBF was irradiated with light of 200 to 300 nm, it emitted ultraviolet light having a peak at around 321 nm and a half-value width of about 20 nm. A subpeak was confirmed around 390 nm, probably because the purification of BCBF was insufficient. The results are shown in Table 1 and FIG.

[Example 3]
Measure the excitation spectrum and emission spectrum of the compound represented by the following formula (1c) [9,9-bis (4-hydroxy-3-methylphenyl) fluorene (BCF), manufactured by Osaka Gas Chemical Co., Ltd.] in the solid state. did. When the BCF was irradiated with light of 200 to 310 nm, it emitted ultraviolet light having a peak at around 335 nm and a half-value width of about 20 nm. The results are shown in Table 1 and FIG.

[Example 4]
The excitation spectrum and emission spectrum of the compound represented by the following formula (1d) [9,9-bis (p-tolyl) fluorene (BTF), manufactured by Kanto Chemical Co., Inc.] were measured. When the BTF was irradiated with light of 200 to 310 nm, it emitted ultraviolet light having a peak in the vicinity of 341 nm and having a half-value width of about 45 nm. The emission quantum efficiency was 6.5%. The results are shown in Table 1 and FIG.

[Example 5]
The excitation spectrum and emission spectrum of the compound represented by the following formula (1e) [9,9-bis (6-hydroxy-2-naphthyl) fluorene (BNF), manufactured by Osaka Gas Chemicals Co., Ltd.] were measured. .. When the BNF was irradiated with light of 200 to 320 nm, it emitted ultraviolet light having a peak in the vicinity of 366 nm and having a half-value width of about 35 nm. The results are shown in Table 1 and FIG.

[Example 6]
The excitation spectrum and emission spectrum of the compound represented by the following formula (1f) [9,9-dimethylformamide (DMF), manufactured by Kanto Chemical Co., Inc.] in a solid state were measured. When the DMF was irradiated with light of 200 to 300 nm, it emitted ultraviolet light having a peak at around 323 nm and a half-value width of about 20 nm. The results are shown in Table 1 and FIG.

[Example 7]
The excitation spectrum and emission spectrum of the compound represented by the following formula (1 g) [fluorene (DHF), manufactured by Osaka Gas Chemicals Co., Ltd.] in a solid state were measured. When the DHF was irradiated with light of 200 to 320 nm, it emitted ultraviolet light having a peak at around 340 nm and having a half-value width of about 25 nm. The results are shown in Table 1 and FIG.

[Example 8]
Excitation spectrum of compound [9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene (bisphenoxyethanol fluorene, BPEF) represented by the following formula (1h)] in the solid state. And the emission spectrum was measured. The BPEF emitted ultraviolet light having a half-value width of about 20 nm having a peak near 333 nm when irradiated with light of 220 to 310 nm. The results are shown in Table 1 and FIG.

As is clear from Table 1 and FIGS. 1 to 8, it was found that Examples 1 to 8 emit near-ultraviolet light having a wavelength of 321 to 366 nm and a half width of 20 to 45 nm.

[Example 9]
The BMBF represented by the above formula (1a) prepared in Synthesis Example 1 was dissolved in dichloromethane (concentration 6.4 × ^10-6 mol / L), and the excitation spectrum and emission spectrum in the solution state were measured. When BMBF was irradiated with light of 220 to 325 nm (excitation peak 304 nm) in dichloromethane, it emitted ultraviolet light having a half-value width of about 25 nm having a peak near 310 nm at the emission end of 303 nm. The emission quantum efficiency was 18.8%. The results are shown in Table 2 and FIG.

[Example 10]
Excitation spectra and emission spectra in a solution state were measured in the same manner as in Example 9 except that BTF represented by the formula (1d) described in Example 4 was used instead of BMBF. When BMBF was irradiated with light of 230 to 320 nm (excitation peak 309 nm) in dichloromethane, it emitted ultraviolet light having a peak at the emission end of 308 nm and having a peak near 314 nm and having a half width of about 20 nm. The emission quantum efficiency was 29.6%. The results are shown in Table 2 and FIG.

[Example 11]
Excitation spectra and emission spectra in a solution state were measured in the same manner as in Example 9 except that DHF represented by the formula (1 g) described in Example 7 was used instead of BMBF. When DHF was irradiated with light of 230 to 315 nm (excitation peak 301 nm) in dichloromethane, it emitted ultraviolet light having a peak at the emission end of 299 nm and having a peak near 315 nm and having a half width of about 30 nm. The results are shown in Table 2 and FIG.

For BMBF, BTF and DHF used in Examples 1, 4, 7 and 9-11, the energy levels and energy gaps of the molecular orbitals (LUMO and HOMO) are calculated by the Density Functional Theory (DFT). did. The results are shown in Table 3.

As is clear from Tables 2 and 3, when the calculation result (showing the case where the energy is the largest) and the experimental result (the emission end on the short wavelength side with the largest energy) are compared, the energy gap calculated by the calculation is large. The wavelengths of λ _{ex, max} and the emission end in dichloromethane became smaller, and the tendencies of the calculation results and the experimental results were in good agreement. On the other hand, the λ _{ex, max} and λ _{em, max} and the light emitting end in the solid state (Examples 1, 4 and 7) shown in Table 1 and FIGS. 1, 4 and 7 are unexpectedly different from the tendency of the calculation result. BMBF emitted at the shortest wavelength.

For BMBF, a single crystal of BMBF was prepared by recrystallization from tetrahydrofuran (THF), and the single crystal X-ray structure analysis was performed. The results are shown in Table 4.

From the results of single crystal X-ray structure analysis, no intermolecular interaction due to π-π stacking was observed in the BMBF crystal. In BMBF, it is considered that the benzyl group substituted at the 9,9-position of the fluorene skeleton suppresses the approach between molecules. From this result, it is considered that BMBF was able to emit ultraviolet light having a shorter wavelength by having a benzyl group at the 9,9-position in a solid state at room temperature.

<Light emission characteristics of coating film containing fluorene compound>
[Synthesis Example 3]
1 mmol of trimethoxyphenylsilane, 1.5 mL of tetrahydrofuran as a solvent, formic acid (60 μL) as an acid catalyst, and water (60 μL) are mixed and heated and stirred at 90 ° C. for 3 hours for hydrolysis reaction and condensation reaction. And dried. After allowing to cool, wash away the residual acid with pure water, add 1.5 mL of tetrahydrofuran to make a solution again, heat and stir at 110 ° C. for 2 hours, and dry to dry to polyphenylsilsesquioxane (PPSQ). , A compound represented by the following formula) was synthesized.

[Example 12]
A mixed solution (coating agent) prepared by mixing 1 part by weight of BMBF, 5 parts by weight of PPSQ prepared in Synthesis Example 3, and 57 parts by weight of toluene as a solvent was prepared by a quartz substrate (Daiko Seisakusho Co., Ltd.). A coating film is formed by applying a spin coater (“1H-D7” manufactured by Mikasa Co., Ltd.) on a “Labo-USQ” manufactured by Mikasa Co., Ltd. and drying at 90 ° C. for 1 hour on a hot plate to remove the solvent. did. The excitation spectrum and the emission spectrum were measured using the formed coating film. When the coating film was irradiated with light of 200 to 300 nm, ultraviolet light having a half-value width of about 25 nm having a peak near 312 nm derived from BMBF was emitted. The results are shown in Table 5 and FIG.

[Example 13]
A mixed solution (coating agent) prepared by mixing 1 part by weight of BCF, 10 parts by weight of polystyrene (PS, PS Japan Corporation), and 100 parts by weight of chloroform as a solvent was added to a quartz substrate ((PS, Co., Ltd.). ) Apply on a spin coater (“1H-D7” manufactured by Mikasa Co., Ltd.) on “Labo-USQ” manufactured by Daiko Seisakusho, and dry on a hot plate at 90 ° C. for 1 hour to remove the solvent. A film was formed. The excitation spectrum and the emission spectrum were measured using the formed coating film. When the coating film was irradiated with light of 200 to 320 nm, ultraviolet light having a peak in the vicinity of 333 nm derived from BCF and having a half width of about 40 nm was emitted. The results are shown in Table 5 and FIG.

[Example 14]
A mixed solution (coating agent) prepared by mixing 1 part by weight of BNF, 10 parts by weight of polycarbonate (PC, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) and 100 parts by weight of chloroform as a solvent is prepared as a quartz substrate (coating agent). Apply on a "Labo-USQ" manufactured by Daiko Seisakusho Co., Ltd. with a spin coater ("1H-D7" manufactured by Mikasa Co., Ltd.) and dry on a hot plate at 90 ° C. for 1 hour to remove the solvent. To form a coating film. The excitation spectrum and the emission spectrum were measured using the formed coating film. When the coating film was irradiated with light of 200 to 340 nm, ultraviolet light having a peak at around 364 nm derived from BNF and having a half width of about 50 nm was emitted. The results are shown in Table 5 and FIG.

[Example 15]
A mixed solution (coating agent) prepared by mixing 1 part by weight of DHF, 10 parts by weight of polymethylmethacrylate (PMMA, manufactured by Mitsubishi Rayon Co., Ltd.) and 100 parts by weight of chloroform as a solvent was prepared as a quartz substrate (coating agent). Apply on a spin coater ("1H-D7" manufactured by Mikasa Co., Ltd.) on "Labo-USQ" manufactured by Daiko Seisakusho Co., Ltd., and dry on a hot plate at 90 ° C. for 1 hour to remove the solvent. To form a coating film. The excitation spectrum and the emission spectrum were measured using the formed coating film. When the coating film was irradiated with light of 200 to 300 nm, ultraviolet light having a peak at around 333 nm derived from DHF and having a half-value width of about 40 nm was emitted. The results are shown in Table 5 and FIG.

[Example 16]
A mixed solution (coating agent) prepared by mixing 1 part by weight of BPEF, 5 parts by weight of PPSQ prepared in Synthesis Example 3, and 57 parts by weight of toluene as a solvent was prepared by a quartz substrate (Daiko Seisakusho Co., Ltd.). A coating film is formed by applying a spin coater (“1H-D7” manufactured by Mikasa Co., Ltd.) on a “Labo-USQ” manufactured by Mikasa Co., Ltd. and drying at 90 ° C. for 1 hour on a hot plate to remove the solvent. did. The excitation spectrum and the emission spectrum were measured using the formed coating film. When the coating film was irradiated with light of 200 to 310 nm, ultraviolet light having a peak in the vicinity of 321 nm derived from BPEF and having a half width of about 35 nm was emitted. The results are shown in Table 5 and FIG.

As is clear from Table 5 and FIGS. 12 to 16, it was found that in the examples, near-ultraviolet light having a wavelength of 312 to 364 nm and a half width of 25 to 50 nm was emitted. Further, in Examples 12 to 16, even if the coating film is formed, near-ultraviolet light having a narrow half-value width is emitted as in Examples 1, 3, 5, 7 and 8, and therefore, it is used as a coating agent for security inks and the like. It can be seen that it can be effectively used in various applications.

[Example 17]
The coating film was prepared in the same manner as in Example 12 except that the ratios of BMBF and PPSQ were adjusted so that the molar ratio of BMBF and trimethoxyphenylsilane as a raw material of PPSQ was the former / the latter = 1/4. Formed. The total light transmittance, haze value, excitation spectrum and emission spectrum were measured using the formed coating film. In addition, the surface and cross section of the coating film were observed by FE-SEM. The results are shown in Tables 6-7 and FIGS. 17-18.

[Example 18]
BTF is used instead of BMBF, and the ratio of BTF and PPSQ is adjusted except that the molar ratio of BTF to trimethoxyphenylsilane which is a raw material of PPSQ is the former / the latter = 1/4. A coating film was formed in the same manner as in Example 17. The total light transmittance, haze value, excitation spectrum and emission spectrum were measured using the formed coating film. In addition, the surface and cross section of the coating film were observed by FE-SEM. The results are shown in Tables 6-7 and FIGS. 19-20.

[Example 19]
DHF was used instead of BMBF, except that the ratio of DHF and PPSQ was adjusted so that the molar ratio of DHF and trimethoxyphenylsilane, which is a raw material of PPSQ, was the former / the latter = 1/4. A coating film was formed in the same manner as in Example 17. The total light transmittance and the haze value were measured using the formed coating film. In addition, the surface and cross section of the coating film were observed by FE-SEM. The results are shown in Table 6 and FIG.

As is clear from Table 6 and FIGS. 18, 20 and 21, the coating films obtained in Examples 17 to 19 had high total light transmittance and low haze value. Therefore, it is considered that the fluorene compound is uniformly dispersed in PPSQ. Among them, in Examples 17 and 18 using the fluorene compound having a substituent at the 9,9-position, a film having less shape disorder and a lower haze value was obtained. It is considered that the interaction between the substituent at the 9-position and PPSQ contributes to more uniform dispersion.

Further, as is clear from Table 7 and FIGS. 17 and 19, the excitation and emission peaks of Examples 17 and 18 in which the fluorene compound is combined with PPSQ are the excitation and emission of the solid state of the fluorene compound (Examples 1 and 4). The wavelength was shortened compared to the peak, and it was found to be similar to the excitation and emission peaks of the dichloromethane solutions (Examples 9 and 10). Further, the emission quantum efficiencies of Examples 17 and 18 were greatly improved as compared with the solid state (Examples 1 and 4), and showed almost the same value as the solution state (Examples 9 and 10). Therefore, it is considered that the concentration quenching was suppressed by combining with PPSQ.

<Light emission characteristics of a coating film using a fluorene compound as a sensitizer>
[Example 20]
BMBF, Ir ( Fppy ) ₃ (a compound represented by the following formula, manufactured by Sigma-Aldrich Co., Ltd.) as a blue phosphorescent material, and PPSQ prepared in Synthesis Example 3 were mixed in a molar ratio of BMBF /. Ir (Fppy) ₃ / PPSQ = 5/1/20 (For PPSQ, it is converted as the number of moles of the silicon atom Si (or the raw material trimethoxysilane) in PPSQ), and further, as a solvent. A spin coater (Mikasa Co., Ltd. " A coating film was formed by applying 1HD7 ”) and drying on a hot plate at 90 ° C. for 1 hour to remove the solvent. The excitation spectrum and the emission spectrum were measured using the formed coating film. The results are shown in FIG.

As is clear from FIG. 22, the ultraviolet emission derived from BMBF confirmed in the wavelengths around 311 to 312 nm in Examples 12 and 17 is almost eliminated, and only the emission of iridium is observed (maximum wavelength λ _{ex, max} of the excitation spectrum). = 305 nm, maximum wavelength of emission spectrum λ _{em, max} = 476 nm). This indicates that energy is rapidly transferred from the excited state of BMBF to the iridium complex, and that BMBF functions as an antenna (sensitizer) that absorbs light and can sensitize the emission of the iridium complex. ing.

[Example 21]
BPEF and PtOEP as a red phosphorescent material [platinum (II) 2,3,7,8,12,13,17,18-octaethyl-21H, 23H-porphyrin, compound represented by the following formula, Sigma-Aldrich Made by Co., Ltd.] and PPSQ prepared in Synthesis Example 3 in molar ratio BPEF / PtOEP / PPSQ = 5/1/20 (For PPSQ, the silicon atom Si (or raw material trimethoxy) in PPSQ A mixed solution (coating agent) having a solid content concentration of 1% by weight prepared by mixing so as to have a molar number of silane) and then mixing chloroform as a solvent was prepared by a quartz substrate (manufactured by Daiko Seisakusho Co., Ltd.). A coating film was formed by applying a spin coater (“1HD7” manufactured by Mikasa Co., Ltd.) on “Labo-USQ”) and drying on a hot plate at 90 ° C. for 1 hour to remove the solvent. .. The excitation spectrum and the emission spectrum were measured using the formed coating film. The results are shown in FIG.

As is clear from FIG. 23, the ultraviolet emission derived from BPEF confirmed in the vicinity of the wavelength of 321 nm in Example 16 is almost eliminated, and only the emission of the platinum complex is observed (maximum wavelength λ _{ex, max} = 312 nm of the excitation spectrum,). Maximum wavelength of emission spectrum λ _{em, max} = 648 nm). This indicates that energy is rapidly transferred from the excited state of the BPEF to the platinum complex, and that the BPEF functions as an antenna (sensitizer) that absorbs light and can sensitize the emission of the platinum complex. ing.

[Example 22]
BTF and Tb (acac) ₃ (H ₂ O) ₂ [tris (acetylacetonato) terbium (III) (compound represented by the following formula) hydrate as a green phosphorescent material, Sigma-Aldrich (strain) ) And PPSQ prepared in Synthesis Example 3 in molar ratio BTF / Tb (acac) ₃ (H ₂ O) ₂ / PPSQ = 5/1/10 (Note that PPSQ is in PPSQ. A mixed solution (coating agent) having a solid content concentration of 5% by weight prepared by mixing the silicon atom Si (or converted as the number of moles of the raw material trimethoxysilane) with chloroform as a solvent. , Apply on a quartz substrate (“Labo-USQ” manufactured by Daiko Seisakusho Co., Ltd.) with a spin coater (“1H-D7” manufactured by Mikasa Co., Ltd.), and dry on a hot plate at 90 ° C. for 1 hour. A coating was formed by removing the solvent. The excitation spectrum and the emission spectrum were measured using the formed coating film. The results are shown in FIG.

As is clear from FIG. 24, the ultraviolet emission derived from BTF confirmed at the wavelengths of 316 nm and 329 nm in Example 18 is almost eliminated, and only the emission of the terbium complex is observed (maximum wavelength λ _{ex, max} = of the excitation spectrum). 311 nm, maximum wavelength of emission spectrum λ _{em, max} = 549 nm). This indicates that energy is rapidly transferred from the excited state of BTF to the terbium complex, and that BTF functions as an antenna (sensitizer) that absorbs light and can sensitize the emission of the terbium complex. ing.

The illuminant of the present invention (for example, an organic illuminant, an organic-inorganic hybrid illuminant) is soluble in an organic solvent unlike an inorganic illuminant formed of an inorganic material, and is a matrix of various resins and the like. Since it is easy to uniformly disperse in the material, a coating film can be easily or efficiently formed on a substrate having a complicated shape. Therefore, the light emitter of the present invention can be effectively used as, for example, a coating agent (for example, invisible ink), a photoelectric conversion element (for example, a current injection type light emitting element such as an organic EL element), or the like. As the photoelectric conversion element, it is effective for various applications such as a visible light source (display application, etc.) and an ultraviolet light source (UV lamp) [for example, sterilization application, analysis application, high color rendering white LED light source, etc.]. Can be used for.

Claims (12)

The following formula (1)

[In the formula, X is the same or different hydrogen atom, alkyl group or group X ¹ represented by the following formula (X1).

(In the formula, A is an alkylene group or an alkylidene group, m is 0 or 1, Z is an allene ring, R ² is an alkyl group, an aryl group, a hydroxy (poly) alkoxy group or a carboxyl group, and n is an integer of 0 or more. . )
Is shown. ]
A luminescent material containing a fluorene compound represented by and substituted with at least the 9-position . In formula (1), X is a hydrogen atom, C _1-6 alkyl group or group X ¹ , group X ¹ is in formula (X 1), A is C _1-6 alkylene group and Z is C _6-14 . The claim 1 in which the allene ring, R ² is a C _1-6 alkyl group, a C _6-10 aryl group, a hydroxy (mono to deca) C _2-4 alkoxy group or a carboxyl group, and n is an integer of 0 to 5. Luminous body. In formula (1), X is a C _1-4 alkyl group or group X ¹ , and in formula (X ¹ ), A is a C _1-3 alkylene group, m is 1, and Z is C _6- . _10. The light emitter according to claim 1 or 2 , wherein the arene ring, R ² is a C _1-4 alkyl group, a C _6-10 aryl group or a carboxyl group, and n is an integer of 0 to 3. The following formula (1)

(In the formula, X indicates a hydrogen atom.)
A luminescent material containing a fluorene compound represented by (1) and a resin as a binder component. The light emitter according to any one of claims 1 to 4, which contains at least one binder component selected from ( meth) acrylic resin, styrene resin, polycarbonate resin and silicon resin. ₂ . The illuminant according to any one. The luminescent material according to any one of claims 1 to 6 , wherein the fluorene compound represented by the formula (1) is a light emitting material. The luminescent material according to any one of claims 1 to 6 , which comprises a fluorene compound represented by the formula (1) as a sensitizer and a second light emitting material. The light emitting body according to claim 8 , wherein the second light emitting material is a blue light emitting material. The luminescent material according to any one of claims 1 to 9 , which is a coating agent. A method of irradiating a coating film formed by applying the light emitting body according to claim 10 with light, and detecting the light emitted by the coating film by a detection device including a spectroscope and a detector. The light emitter according to any one of claims 1 to 9 , which is a photoelectric conversion element.

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