TW202212455A - Light-emitting composite particles and light-emitting composite particle composition - Google Patents

Abstract

Light-emitting composite particles, each of which has a perovskite-type crystal structure containing A, B and X as components [in the perovskite-type crystal structure, A represents a component located at each vertex in a hexahedron having B at the center thereof, and is a monovalent cation; B represents a component located at a center in a hexahedron having A at each vertex thereof or an octahedron having X at each vertex thereof, and is a metal ion; and X represents a component located at each vertex in an octahedron having B at the center thereof, and comprises at least one anion selected from the group consisting of a halide ion and a thiocyanate ion], and comprises a perovskite compound particle having light-emitting properties and a silicon compound layer formed on at least a portion of the surface of the perovskite compound particle, the light-emitting composite particles having an average particle diameter of 1 to 100 nm.

Description

Luminescent composite particle and luminescent composite particle composition

The present invention relates to a particle of a luminescent semiconductor compound, in particular to a particle of a luminescent perovskite type semiconductor compound.

A perovskite-type semiconductor compound (hereinafter, referred to as a "perovskite compound") is a light-emitting semiconductor compound having a high quantum yield, and attracts attention as a light-emitting material. For example, Patent Document 1 describes a light-emitting film using a perovskite compound as a light-emitting body. The luminescent film of Patent Document 1 has a sea-island structure, and the sea-island structure has: island parts, which are particles of luminescent perovskite compound particles enclosed in a silazane-modified body; and sea parts, which are polymers . The luminescent film of Patent Document 1 is a luminescent material excellent in durability against water vapor. [Prior Art Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2018/212268 [Patent Document 2] International Publication No. 2019/131370

[Problems to be Solved by Invention]

On the other hand, it turns out that the luminescent film of patent document 1 is easily degraded by irradiation of excitation light, and the luminance maintenance rate (maintaining rate of quantum yield×maintaining rate of absorption rate) tends to decrease. Therefore, the light-emitting film of Patent Document 1 still has room for improvement in light resistance.

This invention was made in view of the said subject, and an object is to provide the luminescent particle material containing a perovskite compound which is excellent in light resistance. [Technical means to solve problems]

The present invention provides a luminescent composite particle having perovskite compound particles, a silicon compound layer formed on at least a part of the surface of the perovskite compound particles, and having an average particle size of 1-100 nm, the perovskite compound particles The compound particles have a perovskite crystal structure with A, B, and X as constituents [In the perovskite crystal structure, A is a component located at each vertex of the hexahedron with B as the center, and is a monovalent cation, B is a component located at the center of the hexahedron with A at the vertex and the octahedron with X at the vertex, and is a metal ion, X is a component located at each vertex of the octahedron with B as the center, and is at least one anion selected from the group consisting of a halide ion and a thiocyanate ion], and has luminescence.

In one embodiment, the silicon compound layer includes at least one layer selected from the group consisting of a hydrolyzable silicon compound and a condensate thereof.

In a certain form, the said perovskite compound particle which has luminescence has a primary particle diameter of 1-80 nm.

Furthermore, the present invention provides a luminescent composite particle composition comprising any one of the above-mentioned luminescent composite particles and at least one selected from the group consisting of a dispersion medium, a polymerizable compound, and a polymer.

Furthermore, the present invention provides a film comprising any of the above-mentioned luminescent composite particles.

Furthermore, the present invention provides a laminated structure including the above-mentioned film.

Furthermore, the present invention provides a light-emitting device including the above-described laminated structure.

Moreover, this invention provides the display provided with the said laminated structure.

Furthermore, the present invention provides a scintillator including any one of the above-mentioned luminescent composite particles. [Effect of invention]

According to the present invention, a light-emitting particle material containing a perovskite compound excellent in light resistance can be provided.

1. Luminescent composite particles containing perovskite compounds FIG. 1 is a cross-sectional view schematically showing the structure of the luminescent composite particle of the present invention. The light-emitting composite particle 100 has the perovskite compound particle 10 and the silicon compound layer 20 formed on the surface thereof. Furthermore, the silicon compound layer 20 only needs to be formed on at least a part of the surface of the perovskite compound particle 10 .

<Perovskite Compound Particles> The perovskite compound particles 10 contain a compound having a perovskite-type crystal structure containing A, B, and X as constituents (A, B, and X have the same meanings as described above, and hereinafter referred to as It is called the particle of "perovskite compound (1)"). The structure of the perovskite compound (1) may be any of a three-dimensional structure, a two-dimensional structure, and a quasi-2D structure. In the case of a three-dimensional structure, the compositional formula of the perovskite compound (1) is represented by ABX _(3+δ) . In the case of a two-dimensional structure, the composition formula of the perovskite compound (1) is represented by A ₂ BX _(4+δ) .

Here, δ is a number that can be appropriately changed according to the charge balance of B, and is -0.7 or more and 0.7 or less. For example, when A is a monovalent cation, B is a divalent cation, and X is a monovalent anion, δ can be selected so that the perovskite compound (1) becomes electrically neutral. The fact that the perovskite compound (1) is electrically neutral means that the charge of the perovskite compound (1) is zero.

The perovskite compound (1) includes an octahedron whose center is B and whose vertex is X. The octahedral system is represented by BX ₆ . In the case where the perovskite compound (1) has a three-dimensional structure, the BX ₆ contained in the perovskite compound (1) is shared by two adjacent octahedrons (BX ₆ ) in the crystal on the eight sides One X located at the vertex in the body (BX ₆ ) constitutes a three-dimensional network structure.

When the perovskite compound (1) has a two-dimensional structure, the BX ₆ contained in the perovskite compound (1) is shared by two octahedrons (BX ₆ ) adjacent to each other in the crystal. Two X's located at the vertices of the face (BX ₆ ) share the edges of the octahedron, thereby forming a two-dimensionally connected layer. The perovskite compound (1) has a structure in which layers including BX ₆ of two-dimensional linkage and layers including A are alternately stacked.

The perovskite compound (1) preferably has a three-dimensional structure.

(Constituent A) The A-series monovalent cation constituting the perovskite compound (1). As A, a cesium ion, an organic ammonium ion, or an amidinium ion can be mentioned.

(organic ammonium ion) As an organic ammonium ion of A, the cation represented by following formula (A3) is mentioned specifically,.

[hua 1]

In formula (A3), R ⁶ to R ⁹ each independently represent a hydrogen atom, an alkyl group or a cycloalkyl group. However, at least one of R ⁶ to R ⁹ is an alkyl group or a cycloalkyl group, and all of R ⁶ to R ⁹ do not become hydrogen atoms at the same time.

The alkyl groups represented by R ⁶ to R ⁹ may be linear or branched. In addition, the alkyl groups represented by R ⁶ to R ⁹ may each independently have an amino group as a substituent.

The number of carbon atoms of the alkyl groups represented by R ⁶ to R ⁹ is usually 1 to 20, preferably 1 to 4, more preferably 1 to 3, and still more preferably 1, independently of each other.

The cycloalkyl groups represented by R ⁶ to R ⁹ may each independently have an amino group as a substituent.

The number of carbon atoms of the cycloalkyl group represented by R ⁶ to R ⁹ is usually 3 to 30, preferably 3 to 11, more preferably 3 to 8, each independently. The number of carbon atoms includes the number of carbon atoms of the substituent.

The groups represented by R ⁶ to R ⁹ are each independently preferably a hydrogen atom or an alkyl group.

When the perovskite compound (1) contains the organic ammonium ion represented by the above formula (A3) as A, it is preferable that the number of alkyl groups and cycloalkyl groups that can be contained in the formula (A3) is small. Moreover, it is preferable that the number of carbon atoms of the alkyl group and cycloalkyl group which may be contained in formula (A3) is small. Thereby, the perovskite compound (1) having a three-dimensional structure with high luminous intensity can be obtained.

In the organic ammonium ion represented by formula (A3), it is preferable that the total number of carbon atoms contained in the alkyl group represented by R ⁶ to R ⁹ and the cycloalkyl group is 1 to 4. Moreover, among the organic ammonium ions represented by the formula (A3), it is more preferable that one of R ⁶ to R ⁹ is an alkyl group having 1 to 3 carbon atoms, and three of R ⁶ to R ⁹ are hydrogen atoms. .

Examples of the alkyl groups of R ⁶ to R ⁹ include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopropyl Pentyl, neopentyl, tert-pentyl, 1-methylbutyl, n-hexyl, 2-methylpentyl, 3-methylpentyl, 2,2-dimethylbutyl, 2,3- Dimethylbutyl, n-heptyl, 2-methylhexyl, 3-methylhexyl, 2,2-dimethylpentyl, 2,3-dimethylpentyl, 2,4-dimethylpentyl , 3,3-dimethylpentyl, 3-ethylpentyl, 2,2,3-trimethylbutyl, n-octyl, isooctyl, 2-ethylhexyl, nonyl, decyl , undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl .

As the cycloalkyl group of R ⁶ to R ⁹ , the alkyl group having 3 or more carbon atoms exemplified in the alkyl group of R ⁶ to R ⁹ can each independently form a ring. As an example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, a norxyl group, an isoxyl group, and a 1-adamantyl group can be exemplified. , 2-adamantyl, tricyclodecyl, etc.

The organic ammonium ion represented by A is preferably CH ₃ NH ₃ ⁺ (also referred to as methylammonium ion), C ₂ H ₅ NH ₃ ⁺ (also referred to as ethylammonium ion) or C ₃ H ₇ NH ₃ ⁺ (also referred to as propylammonium ion), more preferably methylammonium ion or ethylammonium ion, and still more preferably methylammonium ion.

(Amidinonium ion) As the amidinium ion represented by A, the amidinium ion represented by the following formula (A4) may, for example, be mentioned.

(R ¹⁰ R ¹¹ N=CH-NR ¹² R ¹³ ) ⁺・・・(A4)

In formula (A4), R ¹⁰ to R ¹³ each independently represent a hydrogen atom, an alkyl group or a cycloalkyl group.

The alkyl groups represented by R ¹⁰ to R ¹³ may each independently be linear or branched. In addition, the alkyl groups represented by R ¹⁰ to R ¹³ may each independently have an amine group as a substituent.

The number of carbon atoms of the alkyl groups represented by R ¹⁰ to R ¹³ is usually 1 to 20, preferably 1 to 4, and more preferably 1 to 3, each independently.

The cycloalkyl groups represented by R ¹⁰ to R ¹³ may each independently have an amine group as a substituent.

The number of carbon atoms of the cycloalkyl groups represented by R ¹⁰ to R ¹³ is usually 3 to 30, preferably 3 to 11, and more preferably 3 to 8, each independently. The number of carbon atoms includes the number of carbon atoms of the substituent.

Specific examples of the alkyl groups of R ¹⁰ to R ¹³ include the same groups as the alkyl groups exemplified for R ⁶ to R ⁹ , respectively. Specific examples of the cycloalkyl groups of R ¹⁰ to R ¹³ include the same groups as the cycloalkyl groups exemplified for R ⁶ to R ⁹ , independently of each other.

The groups represented by R ¹⁰ to R ¹³ are each independently preferably a hydrogen atom or an alkyl group.

By reducing the number of alkyl groups and cycloalkyl groups contained in the formula (A4), and reducing the number of carbon atoms in the alkyl groups and cycloalkyl groups, a three-dimensional perovskite compound (1) with a higher luminous intensity can be obtained .

Among the amidinium ions, it is preferable that the total number of carbon atoms contained in the alkyl group represented by R ¹⁰ to R ¹³ and the cycloalkyl group is 1 to 4, and it is more preferable that R ¹⁰ is one with 1 carbon atom. In the alkyl group, R ¹¹ to R ¹³ are hydrogen atoms.

When A in the perovskite compound (1) is a cesium ion, an organic ammonium ion having 3 or less carbon atoms, or an amidinium ion having 3 or less carbon atoms, the perovskite compound (1) generally has three dimensions. structure.

When A in the perovskite compound (1) is an organic ammonium ion having 4 or more carbon atoms or an amidinium ion having 4 or more carbon atoms, the perovskite compound (1) has a two-dimensional structure and a quasi-two-dimensional structure Either or both of the (quasi-2D) structures. In this case, the perovskite compound (1) may have a two-dimensional structure or a quasi-two-dimensional structure in a part or the whole of the crystal. When a plurality of two-dimensional perovskite-type crystal structures are stacked, they become equivalent to three-dimensional perovskite-type crystal structures (references: P. PBoix et al., J. Phys. Chem. Lett. 2015, 6, 898- 907, etc.).

A in the perovskite compound (1) is preferably a cesium ion or an amidinium ion, more preferably an amidinium ion.

In the perovskite compound (1), only one type of A may be used, or two or more types may be used in combination.

(Constituent B) B constituting the perovskite compound (1) may be one or more metal ions selected from the group consisting of monovalent metal ions, divalent metal ions, and trivalent metal ions. B preferably contains divalent metal ions, more preferably contains at least one metal ion selected from the group consisting of lead ions, tin ions, antimony ions, bismuth ions, and indium ions, and more preferably lead ions or tin ions, especially lead ions.

In the perovskite compound (1), only one type of B may be used, or two or more types may be used in combination.

(Constituent X) X constituting the perovskite compound (1) may be at least one anion selected from the group consisting of halide ions and thiocyanate ions.

As a halide ion, a chloride ion, a bromide ion, a fluoride ion, and an iodide ion are mentioned. X is preferably a bromide ion.

In the perovskite compound (1), only one type of X may be used, or two or more types may be used in combination.

When X contains two or more types of halide ions, the content ratio of the halide ions can be appropriately selected according to the emission wavelength. For example, a combination of a bromide ion and a chloride ion or a combination of a bromide ion and an iodide ion can be used.

X can be appropriately selected corresponding to the desired emission wavelength.

The perovskite compound (1) in which X is a bromide ion can emit fluorescence having a maximum peak intensity in a wavelength range of usually 480 nm or more, preferably 500 nm or more, and more preferably 520 nm or more.

In addition, the perovskite compound (1) in which X is a bromide ion can emit fluorescence having a maximum intensity peak in a wavelength range of usually 700 nm or less, preferably 600 nm or less, and more preferably 580 nm or less. The upper limit value and the lower limit value of the above-mentioned wavelength range can be arbitrarily combined.

When X in the perovskite compound (1) is a bromide ion, the peak of the emitted fluorescence is usually 480-700 nm, preferably 500-600 nm, more preferably 520-580 nm.

The perovskite compound (1) in which X is an iodide ion can emit fluorescence having a maximum peak intensity in a wavelength range of usually 520 nm or more, preferably 530 nm or more, and more preferably 540 nm or more.

In addition, the perovskite compound (1) in which X is an iodide ion can emit fluorescence having a maximum peak intensity in a wavelength range of usually 800 nm or less, preferably 750 nm or less, and more preferably 730 nm or less. The upper limit value and the lower limit value of the above-mentioned wavelength range can be arbitrarily combined.

When X in the perovskite compound (1) is an iodide ion, the peak of the emitted fluorescence is usually 520-800 nm, preferably 530-750 nm, more preferably 540-730 nm.

The perovskite compound (1) in which X is a chloride ion can emit fluorescence having a maximum peak intensity in a wavelength range of usually 300 nm or more, preferably 310 nm or more, and more preferably 330 nm or more.

In addition, the perovskite compound (1) in which X is a chloride ion can emit fluorescence having a maximum peak intensity in a wavelength range of usually 600 nm or less, preferably 580 nm or less, and more preferably 550 nm or less. The upper limit value and the lower limit value of the above-mentioned wavelength range can be arbitrarily combined.

When X in the perovskite compound (1) is a chloride ion, the peak of the emitted fluorescence is usually 300-600 nm, preferably 310-580 nm, more preferably 330-550 nm.

(Example of Perovskite Compound (1) with Three-Dimensional Structure) Preferable examples of the perovskite compound (1) with three-dimensional structure represented by ABX _(3+δ) include CH ₃ NH ₃ PbBr ₃ , CH ₃ NH ₃ PbCl ₃ , CH ₃ NH ₃ PbI ₃ , CH ₃ NH ₃ PbBr _(3-y) I _y (0<y<3), CH ₃ NH ₃ PbBr _(3-y) C _y (0<y) <3), (H ₂ N=CH-NH ₂ )PbBr ₃ , (H ₂ N=CH-NH ₂ )PbCl ₃ , (H ₂ N=CH-NH ₂ )PbI ₃ .

Preferable examples of the three-dimensional perovskite compound (1) include: CH ₃ NH ₃ Pb _(1-a) Ca _a Br ₃ (0<a≦0.7), CH ₃ NH ₃ Pb _{(1 -a)} Sr _a Br ₃ (0<a≦0.7), CH ₃ NH ₃ Pb _(1-a) La _a Br _(3+δ) (0<a≦0.7, 0<δ≦0.7), CH ₃ NH ₃ Pb _(1-a) Ba _a Br ₃ (0＜a≦0.7), CH ₃ NH ₃ Pb _(1-a) Dy _a Br _(3+δ) (0＜a≦0.7, 0＜δ≦0.7) .

Preferable examples of the three-dimensional perovskite compound (1) include CH ₃ NH ₃ Pb _(1-a) Na _a Br _(3+δ) (0<a≦0.7, -0.7≦δ) <0), CH ₃ NH ₃ Pb _(1-a) Li _a Br _(3+δ) (0<a≦0.7, -0.7≦δ<0).

Preferable examples of the three-dimensional perovskite compound (1) include CsPb _(1-a) Na _a Br _(3+δ) (0<a≦0.7, -0.7≦δ<0), CsPb _(1-a) Li _a Br _(3+δ) (0<a≦0.7, -0.7≦δ<0).

As a preferred example of the three-dimensional perovskite compound (1), CH ₃ NH ₃ Pb _(1-a) Na _a Br _(3+δ-y) I _y (0<a≦0.7, -0.7≦δ<0, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Li _a Br _(3+δ-y) I _y (0<a≦0.7, -0.7≦δ<0, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Na _a Br _(3+δ-y) Cl _y (0<a≦0.7, -0.7≦δ<0, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Li _a Br _(3+δ-y) C _y (0<a≦0.7, -0.7≦δ<0, 0<y<3).

As a preferred example of the three-dimensional perovskite compound (1), (H ₂ N=CH-NH ₂ )Pb _(1-a) Na _a Br _(3+δ) (0<a≦ 0.7, -0.7≦δ＜0), (H ₂ N=CH-NH ₂ )Pb _(1-a) Li _a Br _(3+δ) (0＜a≦0.7, -0.7≦δ＜0), ( H ₂ N=CH-NH ₂ )Pb _(1-a) Na _a Br _(3+δ-y) I _y (0<a≦0.7, -0.7≦δ<0, 0<y<3), (H ₂ N=CH-NH ₂ )Pb _(1-a) Na _a Br _(3+δ-y) C _y (0<a≦0.7, -0.7≦δ<0, 0<y<3).

Preferable examples of the three-dimensional perovskite compound (1) include CsPbBr ₃ , CsPbCl ₃ , CsPbI ₃ , CsPbBr _(3-y) I _y (0<y<3), CsPbBr _{(3- y)} C _y (0<y<3).

Preferable examples of the three-dimensional perovskite compound (1) include CH ₃ NH ₃ Pb _(1-a) Zn _a Br ₃ (0<a≦0.7), CH ₃ NH ₃ Pb _{(1 -a)} Al _a Br _(3+δ) (0＜a≦0.7, 0≦δ≦0.7), CH ₃ NH ₃ Pb _(1-a) Co _a Br ₃ (0＜a≦0.7), CH ₃ NH ₃ Pb _(1-a) Mn _a Br ₃ (0<a≦0.7), CH ₃ NH ₃ Pb _(1-a) Mg _a Br ₃ (0<a≦0.7).

Preferable examples of the three-dimensional perovskite compound (1) include CsPb _(1-a) Zn _a Br ₃ (0<a≦0.7), CsPb _(1-a) Al _a Br _{(3 +δ)} (0＜a≦0.7, 0＜δ≦0.7), CsPb _(1-a) Co _a Br ₃ (0＜a≦0.7), CsPb _(1-a) Mn _a Br ₃ (0＜a≦ 0.7), CsPb _(1-a) Mg _a Br ₃ (0<a≦0.7).

Preferable examples of the three-dimensional perovskite compound (1) include CH ₃ NH ₃ Pb _(1-a) Zn _a Br _(3-y) I _y (0<a≦0.7, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Al _a Br _(3+δ-y) I _y (0<a≦0.7, 0<δ≦0.7, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Co _a Br _(3-y) I _y (0＜a≦0.7, 0＜y＜3), CH ₃ NH ₃ Pb _(1-a) Mn _a Br _(3-y) I _y (0<a≦0.7, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Mg _a Br _(3-y) I _y (0<a≦0.7, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Zn _a Br _(3-y) C _y (0<a≦0.7, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Al _a Br _{(3+δ -y)} Cl _y (0<a≦0.7, 0<δ≦0.7, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Co _a Br _(3+δ-y) Cl _y (0< a≦0.7, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Mn _a Br _(3-y) Cl _y (0<a≦0.7, 0<y<3), CH ₃ NH ₃ Pb _(1-a) Mg _a Br _(3-y) Cl _y (0<a≦0.7, 0<y<3).

Preferable examples of the three-dimensional perovskite compound (1) include (H ₂ N=CH-NH ₂ )Zn _a Br ₃ (0<a≦0.7), (H ₂ N=CH- NH ₂ )Mg _a Br ₃ (0<a≦0.7), (H ₂ N=CH-NH ₂ )Pb _(1-a) Zn _a Br _(3-y) I _y (0<a≦0.7, 0<y<3), (H ₂ N=CH-NH ₂ )Pb _(1-a) Zn _a Br _(3-y) C _y (0<a≦0.7, 0<y<3).

Among the above-mentioned three-dimensional perovskite compounds (1), more preferred are CsPbBr ₃ , CsPbBr _(3-y) I _y (0<y<3), (H ₂ N=CH-NH ₂ )PbBr ₃ , and further Preferred is (H ₂ N=CH-NH ₂ )PbBr ₃ .

(Example of the two-dimensional structure perovskite compound (1)) As preferred examples of the two-dimensional structure perovskite compound (1), (C 4 H 9 NH 3 ) 2 PbBr 4 , (C ₄ H ₉ NH ₃ ) ₂ PbBr ₄ , (C _{4H9NH3 ) 2PbCl4 , ( C4H9NH3 ) 2PbI4 , ( C7H15NH3 ) 2PbBr4 , ( C7H15NH3 ) 2PbCl4 , ( C7H 15} NH ₃ ) ₂ PbI ₄ , (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Li _a Br _(4+δ) (0<a≦0.7, -0.7≦δ<0), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Na _a Br _(4+δ) (0<a≦0.7, -0.7≦δ<0), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Rb _a Br _(4+δ) (0<a≦0.7, -0.7≦δ<0).

As a preferred example of the two-dimensional perovskite compound (1), (C ₇ H ₁₅ NH ₃ ) ₂ Pb _(1-a) Na _a Br _(4+δ) (0<a≦) 0.7, -0.7≦δ＜0), (C ₇ H ₁₅ NH ₃ ) ₂ Pb _(1-a) Li _a Br _(4+δ) (0＜a≦0.7, -0.7≦δ＜0), (C ₇ H ₁₅ NH ₃ ) ₂ Pb _(1-a) Rb _a Br _(4+δ) (0<a≦0.7, -0.7≦δ<0).

As a preferred example of the two-dimensional perovskite compound (1), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Na _a Br _(4+δ-y) I _y ( 0<a≦0.7, -0.7≦δ<0, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Li _a Br _(4+δ-y) I _y (0< a≦0.7, -0.7≦δ<0, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Rb _a Br _(4+δ-y) I _y (0<a≦ 0.7, -0.7≦δ<0, 0<y<4).

As a preferred example of the two-dimensional perovskite compound (1), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Na _a Br _(4+δ-y) C _y ( 0<a≦0.7, -0.7≦δ<0, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Li _a Br _(4+δ-y) C _y (0< a≦0.7, -0.7≦δ<0, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Rb _a Br _(4+δ-y) C _y (0<a≦ 0.7, -0.7≦δ<0, 0<y<4).

Preferable examples of the two-dimensional perovskite compound (1) include (C ₄ H ₉ NH ₃ ) ₂ PbBr ₄ and (C ₇ H ₁₅ NH ₃ ) ₂ PbBr ₄ .

Preferable examples of the two-dimensional perovskite compound (1) include (C ₄ H ₉ NH ₃ ) ₂ PbBr _(4-y) C _y (0<y<4), (C ₄ H ₉ NH ₃ ) ₂ PbBr _(4-y) I _y (0<y<4).

Preferable examples of the two-dimensional perovskite compound (1) include (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Zn _a Br ₄ (0<a≦0.7), ( C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Mg _a Br ₄ (0＜a≦0.7), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Co _a Br ₄ (0＜a≦0.7) 0.7), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Mn _a Br ₄ (0<a≦0.7).

Preferable examples of the two-dimensional perovskite compound (1) include (C ₇ H ₁₅ NH ₃ ) ₂ Pb _(1-a) Zn _a Br ₄ (0<a≦0.7), ( C ₇ H ₁₅ NH ₃ ) ₂ Pb _(1-a) Mg _a Br ₄ (0＜a≦0.7), (C ₇ H ₁₅ NH ₃ ) ₂ Pb _(1-a) Co _a Br ₄ (0＜a≦0.7) 0.7), (C ₇ H ₁₅ NH ₃ ) ₂ Pb _(1-a) Mn _a Br ₄ (0<a≦0.7).

As a preferred example of the two-dimensional perovskite compound (1), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Zn _a Br _(4-y) I _y (0< a≦0.7, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Mg _a Br _(4-y) I _y (0<a≦0.7, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Co _a Br _(4-y) I _y (0<a≦0.7, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _{( 1-a)} Mn _a Br _(4-y) I _y (0<a≦0.7, 0<y<4).

As a preferred example of the two-dimensional perovskite compound (1), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Zn _a Br _(4-y) C _y (0< a≦0.7, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Mg _a Br _(4-y) C _y (0<a≦0.7, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Co _a Br _(4-y) C _y (0<a≦0.7, 0<y<4), (C ₄ H ₉ NH ₃ ) ₂ Pb _{( 1-a)} Mn _a Br _(4-y) C _y (0<a≦0.7, 0<y<4).

<Primary particle size of perovskite compound particles> In this specification, the primary particle size of the perovskite compound particles is the average particle size of the perovskite compound particles in the mixture of perovskite compound particles composed of a plurality of perovskite compound particles, and the average particle size is preferably 1.0 to 80.0 nm or less. From the viewpoint that the luminescent composite particles can be stably dispersed in the dispersion medium, the average particle diameter of the perovskite compound particles is preferably 3.0 nm or more, more preferably 5.0 nm or more, and still more preferably 10.0 nm or more. In addition, from the viewpoint of obtaining luminescent composite particles with high emission intensity, the average particle diameter of the perovskite compound particles is preferably 50.0 nm or less, more preferably 30.0 nm or less, and still more preferably 20.0 nm or less.

The average particle diameter of the perovskite compound particles can be measured by observation using, for example, a transmission electron microscope (hereinafter, also referred to as TEM) or a scanning electron microscope (hereinafter, also referred to as SEM). Specifically, by TEM or SEM, the lengths of the longest sides of randomly selected 30 or more perovskite compound particles having a cubic or cuboid shape are measured, and the arithmetic mean of the measured values can be calculated. The average particle size.

As a method of observing perovskite compound particles, for example, a method of observing a dispersion liquid composition containing perovskite compound particles using SEM, TEM, or the like can be mentioned. Furthermore, detailed element distribution can be analyzed by energy dispersive X-ray analysis (EDX) measurement using SEM or TEM. From the viewpoint of high spatial resolution, a method of observing by TEM is preferable.

<Silicon compound layer> The silicon compound layer 20 is a layer containing at least one compound selected from the group consisting of a hydrolyzable silicon compound and its condensate. Hydrolyzable silicon compound refers to a silicon compound having a hydrolyzable functional group and forming a Si-O-Si bond after condensation. "Condensation" refers to the hydrolysis of silicon compounds with Si-N bonds, Si-SR bonds (R is hydrogen atom or organic group) or Si-OR bond (R is hydrogen atom or organic group) to generate Si-O-Si Bonded silicon compound. Si-O-Si bonds can be formed in intermolecular condensation reactions or in intramolecular condensation reactions.

Preferred examples of the hydrolyzable silicon compound include silazane and hydrolyzable silane compounds (hereinafter, these are referred to as "hydrolyzable silicon compound (2)"). By covering the surface of the perovskite compound particle 10 with the silicon compound layer 20, the effect of improving the quantum yield and shortening the emission wavelength is obtained.

＜Silazane＞ Silazane is a compound with Si-N-Si bond. The silazane may be linear, branched or cyclic.

The silazane can be a low molecular silazane or a high molecular silazane. In this specification, a polymer silazane may be described as polysilazane.

In this specification, "low molecular weight" means that the number average molecular weight is less than 600. In addition, in this specification, "polymer" means that the number average molecular weight is 600 or more and 2000 or less.

In this specification, "number average molecular weight" means a polystyrene conversion value measured by a gel permeation chromatography (GPC) method.

(low molecular weight silazanes) As the low molecular weight silazane, for example, disilazane represented by the following formula (B1) is preferable.

[hua 2]

In formula (B1), R ¹⁴ and R ¹⁵ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a carbon An aryl group having 6 to 20 atoms or an alkylsilyl group having 1 to 20 carbon atoms.

R ¹⁴ and R ¹⁵ may have a substituent such as an amino group. The plurality of R ¹⁵ present may be the same or different.

As the low molecular weight silazane represented by the formula (B1), 1,3-divinyl-1,1,3,3-tetramethyldisilazane, 1,3-diphenyltetrakis Methyldisilazane, and 1,1,1,3,3,3-hexamethyldisilazane.

(low molecular weight silazanes) As the low molecular weight silazane, for example, a low molecular weight silazane represented by the following formula (B2) is also preferred.

[hua 3]

In formula (B2), R ¹⁴ and R ¹⁵ are the same as R ¹⁴ and R ¹⁵ in the above formula (B1).

The plurality of R ¹⁴ present may be the same or different. The plurality of R ¹⁵ present may be the same or different.

In formula (B2), n ₁ represents an integer of 1 or more and 20 or less. n ₁ may be an integer of 1 or more and 10 or less, and may be 1 or 2.

As the low molecular weight silazane represented by the formula (B2), octamethylcyclotetrasilazane, 2,2,4,4,6,6-hexamethylcyclotrisilazane, and 2 ,4,6-trimethyl-2,4,6-trivinylcyclotrisilazan.

As the low molecular weight silazane, octamethylcyclotetrasilazane and 1,3-diphenyltetramethyldisilazane are preferable, and octamethylcyclotetrasilazane is more preferable.

(Polymer silazane) As a polymer silazane, for example, a polymer silazane (polysilazane) represented by the following formula (B3) is preferable.

Polysilazane is a polymer compound with Si-N-Si bond. The structural unit of the polysilazane represented by formula (B3) may be one kind or plural kinds.

[hua 4]

In formula (B3), R ¹⁴ and R ¹⁵ are the same as R ¹⁴ and R ¹⁵ in the above-mentioned formula (B1).

In formula (B3), * represents a bonding bond. R ¹⁴ is bonded to the bond of the N atom at the end of the molecular chain. R ¹⁵ is bonded to the bonding bond of the Si atom at the end of the molecular chain.

The plurality of R ¹⁴ present may be the same or different. The plurality of R ¹⁵ present may be the same or different.

m represents an integer of 2 or more and 10000 or less.

The polysilazane represented by the formula (B3) can be, for example, a perhydropolysilazane in which both R ¹⁴ and R ¹⁵ are hydrogen atoms.

Moreover, the polysilazane represented by formula (B3) may be, for example, an organopolysilazane in which at least one R ¹⁵ is a group other than a hydrogen atom. The perhydropolysilazane and the organopolysilazane may be appropriately selected according to the application, and may be used in combination.

From the viewpoint of improving the dispersibility of the luminescent composite particles and improving the effect of suppressing aggregation, it is preferable that the silicon compound layer contains the organopolysilazane represented by the formula (B3).

As the organopolysilazane represented by the formula (B3), at least one of R ¹⁴ and R ¹⁵ may be an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 1 to 20 carbon atoms, or an alkenyl group having 3 carbon atoms. Organopolysilazane of a cycloalkyl group of ~20, an aryl group of 6 to 20 carbon atoms, or an alkylsilyl group of 1 to 20 carbon atoms.

Among them, the organopolysilazane represented by the formula (B3) and wherein at least one of R ¹⁴ and R ¹⁵ is a methyl group is preferred.

(Polymer silazane) As the polymer silazane, for example, polysilazane having a structure represented by the following formula (B4) is also preferred.

Polysilazane may have a ring structure in a part of the molecule, for example, may have a structure represented by formula (B4).

[hua 5]

In formula (B4), * represents a bonding bond. The bond of the formula (B4) may also be bonded to the bond of the polysilazane represented by the formula (B3) or the bond of the structural unit of the polysilazane represented by the formula (B3).

In addition, when the polysilazane contains a plurality of structures represented by the formula (B4) in the molecule, the bonding bonds of the structures represented by the formula (B4) can also be combined with other structures represented by the formula (B4). The bond key is directly bonded.

Bonds not bound to polysilazane represented by formula (B3), bonds to structural units of polysilazane represented by formula (B3), and bonds to other structures represented by formula (B4) The N atom to which any one of the bonds is bonded is bonded with R ¹⁴ .

Bonds not bound to polysilazane represented by formula (B3), bonds to structural units of polysilazane represented by formula (B3), and bonds to other structures represented by formula (B4) The Si atom to which any one of the bonds is bonded has R ¹⁵ in the bond bond.

n ₂ represents an integer of 1 or more and 10000 or less. n ₂ may be an integer of 1 or more and 10 or less, and may be 1 or 2.

From the viewpoint of improving the dispersibility of the luminescent composite particles and improving the effect of suppressing aggregation, it is preferable that the silicon compound layer contains an organopolysilazane having a structure represented by formula (B4).

As the organopolysilazane having the structure represented by the formula (B4), at least one bond may be bonded to R ¹⁴ or R ¹⁵ , and at least one of R ¹⁴ and R ¹⁵ has a carbon number of 1 ～20 alkyl groups, alkenyl groups with 1 to 20 carbon atoms, cycloalkyl groups with 3 to 20 carbon atoms, aryl groups with 6 to 20 carbon atoms, or organic alkylsilyl groups with 1 to 20 carbon atoms Polysilazane.

Among them, a polysilazane comprising the structure represented by the formula (B4) and having at least one bonding bond with R ¹⁴ or R ¹⁵ and at least one of R ¹⁴ and R ¹⁵ being a methyl group is preferred.

Ordinary polysilazane has, for example, a structure having a linear structure and a ring structure such as a 6-membered ring or an 8-membered ring, that is, the structures represented by the above-mentioned formula (B3) and the above-mentioned formula (B4). The molecular weight of ordinary polysilazane is about 600-2000 (in terms of polystyrene conversion) in terms of number average molecular weight (Mn), and it can be a liquid or solid substance depending on the molecular weight.

As the polysilazane, commercially available products can be used. Examples of commercially available products include: NN120-10, NN120-20, NAX120-20, NN110, NAX120, NAX110, NL120A, NL110A, NL150A, NP110, NP140 (AZ ELECTRONIC MATERIALS Co., Ltd.) and AZNN-120-20, Durazane (registered trademark) 1500 Slow Cure, Durazane 1500 Rapid Cure, Durazane 1800, and Durazane 1033 (manufactured by Merck Performance Materials Co., Ltd.), and the like.

The polysilazane is preferably AZNN-120-20, Durazane1500 Slow Cure, Durazane1500 Rapid Cure, more preferably Durazane1500 Slow Cure.

<Condensation product of silazane>

The condensate of silazane is preferably a condensate of disilazane represented by the above formula (B1), a condensate of a low molecular weight silazane represented by the above formula (B2), The condensate of polysilazane represented, and the condensate of polysilazane having the structure represented by the above formula (B4) in the molecule.

Regarding the condensate of low-molecular-weight silazanes represented by formula (B2), silicon atoms not bonded to nitrogen atoms relative to all silicon atoms contained in the condensate of low-molecular-weight silazanes represented by formula (B2) The ratio of atoms is preferably 0.1 to 100%. In addition, the ratio of silicon atoms not bonded to nitrogen atoms is more preferably 10 to 98%, further preferably 30 to 95%.

In addition, the "ratio of silicon atoms not bonded to nitrogen atoms" uses the following measured value, by ((Si(mol))-(N(mol) in Si-N bond))/Si (Mole) × 100 to obtain. In consideration of the condensation reaction, "the ratio of silicon atoms not bonded to nitrogen atoms" means "the ratio of silicon atoms contained in siloxane bonds generated in the condensation treatment".

Regarding the condensate of polysilazane represented by formula (B3), with respect to all silicon atoms contained in the condensate of polysilazane represented by formula (B3), the fraction of silicon atoms not bonded to nitrogen atoms The ratio is preferably 0.1 to 100%. In addition, the ratio of silicon atoms not bonded to nitrogen atoms is more preferably 10 to 98%, further preferably 30 to 95%.

Regarding the condensate of polysilazane having the structure represented by the formula (B4), with respect to all the silicon atoms contained in the condensate of the polysilazane having the structure represented by the formula (B4), no nitrogen atom is attached to the condensate. The ratio of bonded silicon atoms is preferably 0.1 to 99%. In addition, the ratio of silicon atoms not bonded to nitrogen atoms is more preferably 10 to 97%, further preferably 30 to 95%.

The number of Si atoms and the number of Si-N bonds in the condensate can be measured by X-ray photoelectron spectroscopy (XPS).

The "ratio of silicon atoms not bonded to nitrogen atoms" obtained by using the measured values obtained by the above method for the condensate is preferably 0.1 to 99%, more preferably 10 to 99%, and further preferably 30 ~95%.

<Hydrolyzable silane compound> As a hydrolyzable silane compound, the silane compound which has an amino group, an alkoxy group, or an alkylthio group is preferable. As the hydrolyzable silane compound, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, dodecyltrimethoxysilane, trimethoxyphenylsilane, 1H ,1H,2H,2H-perfluorooctyltriethoxysilane, trimethoxy(1H,1H,2H,2H-nonafluorohexyl)silane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyl Triethoxysilane.

Among them, from the viewpoint of the durability of the luminescent composite particles, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, trimethoxyphenylsilane, and trimethoxysilane are more preferable. phenyl silane, trimethoxy (1H, 1H, 2H, 2H-nonafluorohexyl) silane.

<Condensate of hydrolyzable silane compound> The condensate of the hydrolyzable silicon compound may be a compound obtainable by condensing the above-mentioned silane compound having an amino group, an alkoxy group or an alkylthio group.

<Particle size of luminescent composite particles> The shape of the luminescent composite particles is not particularly limited, and may be a spherical shape, a deformed spherical shape, a stone shape, or a rugby ball shape. The average particle diameter of the luminescent composite particles is 1 to 100 nm, preferably 5 to 50 nm, more preferably 10 to 30 nm, and still more preferably 15 to 30 nm. By setting the average particle diameter of the luminescent composite particles to be 100 nm or less, luminescent composite particles including coarse perovskite compound particles and aggregated perovskite compound particles can be removed and selectively obtained. Light-emitting composite particles of tiny perovskite compound particles. It is considered that the coarse perovskite compound particles and the aggregated perovskite compound particles have poor light resistance, and by selecting fine perovskite compound particles, the light resistance of the luminescent composite particles is improved.

The average particle diameter of the luminescent composite particles can be measured by a dynamic light scattering method (DLS: Dynamic Light Scattering), for example, by dispersing the particles in a dispersion liquid to take the shape of a dispersion liquid composition. As a measuring method in DLS, the method of measuring the said dispersion liquid composition using a dedicated container (glass tank) is mentioned.

The average particle diameter of the luminescent composite particles can be adjusted by, for example, a known classification method such as filtering a dispersion liquid containing the synthesized luminescent composite particles using a filter having an appropriate pore size.

<Amount of silicon compound layer> In the light-emitting composite particles, from the viewpoint of sufficiently improving the quantum yield, the mass of the silicon compound layer is preferably 1.1 parts by mass or more, more preferably 1.5 parts by mass or more, with respect to the mass of the perovskite compound, and further It is preferably 1.8 parts by mass or more. Further, the mass of the silicon compound layer is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, and still more preferably 20 parts by mass or less, relative to the mass of the perovskite compound.

In addition, the above-mentioned upper limit value and lower limit value can be combined arbitrarily.

2. Luminescent composite particle composition comprising perovskite compound Fig. 2 is a cross-sectional view schematically showing the structure of a composition comprising the luminescent composite particles of the present invention. The luminescent composite particle composition 200 includes the luminescent composite particles 100 and the dispersion medium material 30 . The luminescent composite particles 100 are dispersed in the dispersion medium material 30 .

In the following description, since the function of dispersing the luminescent composite particles is common, the dispersion medium (3), the polymerizable compound (4), and the polymer (5) to be described below are sometimes collectively referred to as "dispersion medium". Material". The material of the dispersion medium is a support medium that does not easily dissolve the perovskite compound particles, and preferably does not dissolve the perovskite compound particles. Moreover, the dispersion medium material may be a mixture containing at least one of the dispersion medium (3), the polymerizable compound (4), and the polymer (5).

Dispersion refers to a state in which particles are suspended in a dispersion medium material or a state in which particles are suspended in a dispersion medium material. When particles are dispersed in the liquid dispersion medium material, a part of the particles may be precipitated.

(dispersion medium (3)) The dispersion medium (3) is an inert compound that exhibits a liquid state at 25° C. and 1 atmospheric pressure and can coexist with the perovskite compound particles. In this specification, the following polymerizable compound (4) is not contained in the dispersion medium (3).

As a dispersion medium (3), the following (a)-(k) are mentioned, for example. (a) Esters (b) Ketones (c) ethers (d) Alcohol (e) Glycol ethers (f) Organic solvent having an amide group (g) Organic solvent having nitrile group (h) Organic solvent with carbonate group (i) Halogenated hydrocarbons (j) Hydrocarbons (k) Dimethyl methylene (l) Ionic liquid

As (a) ester, methyl formate, ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate, pentyl acetate, etc. are mentioned, for example.

As (b) ketone, γ-butyrolactone, N-methyl-2-pyrrolidone, acetone, diisobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, etc. are mentioned.

As (c) ether, diethyl ether, methyl-tert-butyl ether, diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3 -Dioxolane, 4-methyldioxolane, tetrahydrofuran, methyltetrahydrofuran, anisole, phenethyl ether, etc.

As (d) alcohol, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 3-butanol, 1-pentanol, 2-methyl-2 -Butanol, methoxypropanol, diacetone alcohol, cyclohexanol, 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol, etc.

As (e) glycol ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, triethylene glycol dimethyl ether, etc. are mentioned.

(f) As an organic solvent which has an amide group, N,N- dimethylformamide, acetamide, N,N- dimethylacetamide, etc. are mentioned.

(g) As an organic solvent which has a nitrile group, acetonitrile, isobutyronitrile, propionitrile, methoxyacetonitrile, etc. are mentioned.

(h) As an organic solvent which has a carbonate group, ethylene carbonate, propylene carbonate, etc. are mentioned.

As (i) halogenated hydrocarbon, dichloromethane, chloroform, etc. are mentioned.

As (j) hydrocarbon, n-pentane, cyclohexane, n-hexane, 1-octadecene, benzene, toluene, xylene, etc. are mentioned.

(1) As the ionic liquid, cationic ones include ammonium-based, phosphonium-based, and peronium-based ionic liquids, and as anionic ones, AlCl ^4- , NO ^2- , NO ^3- , I ^- , BF ^4- , PF ^6- , AsF ^6- , SbF ^6- , NbF ^6- , TaF ^6- , F(HF)2.3 ^- , p-CH ₃ PhSO ^3- , CH ₃ CO ² - , CF ₃ CO _2- , CH ₃ SO ^3- , CF ₃ SO ^3- , (CF ₃ SO ₂ ) ₃ C ^- , C ₃ F ₇ CO ^2- , C ₄ F ₉ SO ^3- , (CF ₃ SO ₂ ) ₂ N ^- , (C ₂ F ₅ SO ₂ ) ₂ N ^- , (CF ₃ SO ₂ )(CF ₃ CO)N ^- , (CN) ₂ N ^- and the like.

Among these solvents, (a) esters, (b) ketones, (c) ethers, (g) organic solvents having nitrile groups, (h) organic solvents having carbonate groups, (i) halogenated hydrocarbons and ( j) Hydrocarbons are preferred because they have low polarity and do not easily dissolve the luminescent composite particles.

Furthermore, as the dispersion medium (3), (i) halogenated hydrocarbons and (j) hydrocarbons are more preferable.

Only one type of dispersion medium (3) may be used, or two or more types may be used in combination.

(Polymerizable compound (4)) The polymerizable compound means a monomer compound (monomer) having a polymerizable group. As a polymerizable compound, the monomer which is a liquid state at 25 degreeC and 1 atmospheric pressure is mentioned, for example.

For example, in the case of producing at normal temperature and normal pressure, the polymerizable compound is not particularly limited. As a polymerizable compound, well-known polymerizable compounds, such as styrene, an acrylate, a methacrylate, and acrylonitrile, are mentioned, for example. Among them, as the polymerizable compound, either one or both of acrylates and methacrylates, which are monomers of the acrylic resin, are preferred.

The polymerizable compound (4) may be used alone or in combination of two or more.

The ratio of the total amount of acrylate and methacrylate with respect to the total mass of the polymerizable compound (4) may be 10 mol % or more. The ratio may be 30 mol% or more, 50 mol% or more, 80 mol% or more, or 100 mol%.

(Polymer(5)) The polymer (5) is preferably a polymer having a low solubility of the luminescent composite particles at the temperature at which the luminescent composite particle composition is produced.

For example, when it manufactures at normal temperature and normal pressure, it does not specifically limit as a polymer, For example, well-known polymers, such as polystyrene, an acrylic resin, and an epoxy resin, are mentioned. Among them, as the polymer, an acrylic resin is preferable. The acrylic resin contains either or both of a structural unit derived from an acrylate and a structural unit derived from a methacrylate. These resins can be prepared, for example, by polymerizing the polymerizable compound (4) as the corresponding monomer in the luminescent composite particle composition.

The ratio of the total amount of the acrylate-derived structural unit and the methacrylate-derived structural unit with respect to all the structural units contained in the polymer (5) may be 10 mol % or more. The ratio may be 30 mol% or more, 50 mol% or more, 80 mol% or more, or 100 mol%.

The weight average molecular weight of the polymer (5) is preferably 100 to 1,200,000, more preferably 1,000 to 800,000, and still more preferably 5,000 to 150,000.

In this specification, "weight average molecular weight" means the polystyrene conversion value measured by the gel permeation chromatography (GPC) method.

Only one type of polymer (5) may be used, or two or more types may be used in combination.

<Surface modifier (6)> The luminescent composite particle composition may further contain a surface modifier (6). Moreover, you may have other components other than said (1)-(6). For example, a compound having an amorphous structure including some impurities, an element constituting the perovskite compound (1), and a polymerization initiator may be further included.

When the luminescent composite particle composition includes the surface modifier (6), the surface modifier layer is located between the perovskite compound particles and the silicon compound layer.

(Surface Modifier) The surface modifier (6) uses at least one ion or compound selected from the group consisting of ammonium ions, amines, primary to quaternary ammonium cations, ammonium salts, carboxylic acids, carboxylate ions, and carboxylate salts. forming material.

Among them, at least one selected from the group consisting of amines and carboxylic acids is preferably used as the forming material.

The surface modifier (6) is a compound having a function of covering the surface of the perovskite compound particles and stably dispersing them in the luminescent composite particle composition when luminescent composite particles are produced by the following production method.

(ammonium ion, primary to quaternary ammonium cation, ammonium salt) The ammonium ion as the surface modifier (6) and the primary to quaternary ammonium cations are represented by the following formula (A1). The ammonium salt as the surface modifier (6) contains a salt of an ion represented by the following formula (A1).

[hua 6]

In the ion represented by the formula (A1), R ¹ to R ⁴ represent a hydrogen atom or a monovalent hydrocarbon group.

The hydrocarbon group represented by R ¹ to R ⁴ may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. As a saturated hydrocarbon group, an alkyl group or a cycloalkyl group is mentioned.

The alkyl groups represented by R ¹ to R ⁴ may be linear or branched. The number of carbon atoms of the alkyl group represented by R ¹ to R ⁴ is usually 1 to 20, preferably 5 to 20, and more preferably 8 to 20.

The number of carbon atoms in the cycloalkyl group is usually 3-30, preferably 3-20, more preferably 3-11. The number of carbon atoms includes the number of carbon atoms of the substituent.

The unsaturated hydrocarbon groups of R ¹ to R ⁴ may be linear or branched.

The number of carbon atoms in the unsaturated hydrocarbon groups of R ¹ to R ⁴ is usually 2 to 20, preferably 5 to 20, and more preferably 8 to 20.

R ¹ to R ⁴ are preferably a hydrogen atom, an alkyl group or an unsaturated hydrocarbon group. As the unsaturated hydrocarbon group, an alkenyl group is preferable. R ¹ to R ⁴ are preferably alkenyl groups having 8 to 20 carbon atoms.

Specific examples of the alkyl groups of R ¹ to R ⁴ include the alkyl groups exemplified for R ⁶ to R ⁹ .

Specific examples of the cycloalkyl groups of R ¹ to R ⁴ include the cycloalkyl groups exemplified for R ⁶ to R ⁹ .

The alkenyl group of R ¹ to R ⁴ can be exemplified by the linear or branched alkyl groups exemplified above for R ⁶ to R ⁹ , in which any single bond (CC) between carbon atoms is substituted. In the case of a double bond (C=C), the position of the double bond is not limited.

Examples of preferable alkenyl groups for R ¹ to R ⁴ include vinyl, propenyl, 3-butenyl, 2-butenyl, 2-pentenyl, 2-hexenyl, and 2-nonyl. Alkenyl, 2-dodecenyl, 9-octadecenyl.

When the ammonium cation represented by the formula (A1) forms a salt, the counter anion is not particularly limited. As a counter anion, a halide ion, a carboxylate ion, etc. are preferable. As a halide ion, a bromide ion, a chloride ion, an iodide ion, and a fluoride ion are mentioned.

Preferred examples of the ammonium salt having the ammonium cation and the counter anion represented by the formula (A1) include n-octyl ammonium salt and oleyl ammonium salt.

(amine) The amine as the surface modifier (6) can be represented by the following formula (A11).

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In the above formula (A11), R ¹ to R ³ represent the same groups as R ¹ to R ³ in the above formula (A1). Here, at least one of R ¹ to R ³ is a monovalent hydrocarbon group.

The amine used as the surface modifier (6) may be any of primary to tertiary amines, preferably primary amine and secondary amine, more preferably primary amine.

The amine used as the surface modifier (6) is preferably oleylamine.

(Carboxylic acid, carboxylate ion, carboxylate salt) The carboxylate ion as the surface modifier (6) is represented by the following formula (A2). The carboxylate salt as the surface modifier (6) is a salt containing an ion represented by the following formula (A2). R ⁵ -CO ₂ ^-・・・(A2)

As the carboxylic acid of the surface modifier (6), a carboxylic acid in which a proton (H ⁺ ) is bonded to the carboxylate anion represented by the above (A2) may be mentioned.

In the ion represented by the formula (A2), R ⁵ represents a monovalent hydrocarbon group. The hydrocarbon group represented by R ⁵ may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. As a saturated hydrocarbon group, an alkyl group or a cycloalkyl group is mentioned.

The alkyl group represented by R ⁵ may be linear or branched.

The number of carbon atoms of the alkyl group represented by R ⁵ is usually 1-20, preferably 5-20, more preferably 8-20.

The number of carbon atoms in the cycloalkyl group is usually 3-30, preferably 3-20, more preferably 3-11. The number of carbon atoms also includes the number of carbon atoms of the substituent.

The unsaturated hydrocarbon group represented by R ⁵ may be linear or branched.

The number of carbon atoms of the unsaturated hydrocarbon group represented by R ⁵ is usually 2-20, preferably 5-20, more preferably 8-20.

R ⁵ is preferably an alkyl group or an unsaturated hydrocarbon group. As the unsaturated hydrocarbon group, an alkenyl group is preferable.

As a specific example of the alkyl group of R< ⁵ >, the alkyl group exemplified by R< ⁶ >-R< ⁹ > is mentioned. Specific examples of the cycloalkyl group of R ⁵ include the cycloalkyl groups exemplified by R ⁶ to R ⁹ .

Specific examples of the alkenyl group for R ⁵ include the alkenyl groups exemplified for R ⁴ .

The carboxylate anion represented by the formula (A2) is preferably an oleic acid anion.

When the carbochelate anion forms a salt, the counter cation is not particularly limited, and preferred examples include alkali metal cations, alkaline earth metal cations, and ammonium cations.

The carboxylic acid used as the surface modifier (6) is preferably oleic acid.

Among the above-mentioned surface modifiers (6), ammonium salts, ammonium ions, primary to quaternary ammonium cations, carboxylate salts, and carboxylate ions are preferred.

Among ammonium salts and ammonium ions, oleylamine salts and oleylammonium ions are more preferred.

Among carboxylate salts and carboxylate ions, oleate and oleate cations are more preferred.

In the light-emitting composite particle, only one type of the above-mentioned surface modifier (6) may be provided, or two or more types may be used in combination.

<Content of each component in the luminescent composite particle composition> In the luminescent composite particle composition, the content ratio of the luminescent composite particle with respect to the total mass of the luminescent composite particle composition is not particularly limited.

From the viewpoint of preventing concentration quenching, the content ratio is preferably 90% by mass or less, more preferably 40% by mass or less, still more preferably 10% by mass or less, and particularly preferably 3% by mass or less.

Moreover, from the viewpoint of obtaining a good quantum yield, the content ratio is preferably 0.0002 mass % or more, more preferably 0.002 mass % or more, and still more preferably 0.01 mass % or more.

The above upper limit value and lower limit value can be arbitrarily combined.

The content ratio of the luminescent composite particles with respect to the total mass of the luminescent composite particle composition is usually 0.0002 to 90% by mass.

The content ratio of the luminescent composite particles with respect to the total mass of the luminescent composite particle composition is preferably 0.001 to 40 mass %, more preferably 0.002 to 10 mass %, and still more preferably 0.01 to 3 mass %.

In the light-emitting composite particle composition in which the content ratio of the luminescent composite particles to the total mass of the luminescent composite particle composition is within the above-mentioned range, the aggregation of the luminescent composite particles is less likely to occur, and the luminescent properties can be well exhibited. is better.

In the luminescent composite particle composition, the content ratio of the silicon compound layer with respect to the total mass of the luminescent composite particle composition is not particularly limited.

From the viewpoint of improving the dispersibility of the luminescent composite particles and improving the durability, the content ratio is preferably 30% by mass or less, more preferably 10% by mass or less, and still more preferably 7.5% by mass or less.

Moreover, from the viewpoint of improving the durability of the luminescent composite particles, the content ratio is preferably 0.001 mass % or more, more preferably 0.01 mass % or more, and still more preferably 0.1 mass % or more.

The above upper limit value and lower limit value can be arbitrarily combined.

The content ratio of the silicon compound layer with respect to the total mass of the luminescent composite particle composition is usually 0.001 to 30 mass %.

The content ratio of the silicon compound layer with respect to the total mass of the luminescent composite particle composition is preferably 0.001 to 30 mass %, more preferably 0.001 to 10 mass %, and 0.1 to 7.5 mass %.

In the luminescent composite particle composition, the content ratio of the dispersion medium material to the total mass of the luminescent composite particle composition is not particularly limited.

From the viewpoint of improving the dispersibility of the luminescent composite particles and improving the light resistance, the content ratio is preferably 99.99 mass % or less, more preferably 99.9 mass % or less, and still more preferably 99 mass % or less.

Also, from the viewpoint of improving light resistance, the content ratio is preferably 0.1 mass % or more, more preferably 1 mass % or more, more preferably 10 mass % or more, still more preferably 50 mass % or more, and still more preferably 10 mass % or more. Preferably it is 80 mass % or more, Most preferably, it is 90 mass % or more.

The above upper limit value and lower limit value can be arbitrarily combined.

The content ratio of the dispersion medium material to the total mass of the luminescent composite particle composition is usually 0.1 to 99.99 mass %.

The content ratio of the dispersion medium material to the total mass of the luminescent composite particle composition is preferably 1 to 99 mass %, more preferably 10 to 99 mass %, still more preferably 20 to 99 mass %, particularly preferably 50 to 50 mass %. 99% by mass, preferably 90 to 99% by mass.

Moreover, in the above-mentioned luminescent composite particle composition, the total content ratio of the perovskite compound particles, the silicon compound layer and the dispersion medium material may be 90% by mass or more with respect to the total mass of the luminescent composite particle composition. 95 mass % or more, 99 mass % or more may be sufficient, and 100 mass % may be sufficient.

In the luminescent composite particle composition, the content ratio of the surface modifier (6) with respect to the total mass of the luminescent composite particle composition is not particularly limited.

From the viewpoint of improving light resistance, the content ratio is preferably 30% by mass or less, more preferably 1% by mass or less, and still more preferably 0.1% by mass or less.

Moreover, from a viewpoint of improving light durability, the said content ratio becomes like this. Preferably it is 0.0001 mass % or more, More preferably, it is 0.001 mass % or more, More preferably, it is 0.01 mass % or more.

The above upper limit value and lower limit value can be arbitrarily combined.

The content ratio of the surface modifier (6) with respect to the total mass of the luminescent composite particle composition is usually 0.0001 to 30% by mass.

The content ratio of the surface modifier (6) with respect to the total mass of the luminescent composite particle composition is preferably 0.001 to 1 mass %, more preferably 0.01 to 0.1 mass %.

The light-emitting composite particle composition in which the content ratio of the surface modifier (6) to the total mass of the light-emitting composite particle composition is within the above-mentioned range is excellent in light durability, and is preferable in this respect.

With respect to the total mass of the luminescent composite particle composition, the total content ratio of the luminescent composite particles including some impurities, the compound having an amorphous structure of the element constituting the perovskite compound (1), and the polymerization initiator is preferable It is 10 mass % or less, More preferably, it is 5 mass % or less, More preferably, it is 1 mass % or less.

3. Manufacturing method of luminescent composite particles Regarding the production method of perovskite compound particles, known literatures (Nano Lett. 2015, 15, 3692-3696, ACS Nano, 2015, 9, 4533-4542) can be referred to and produced by the method described below.

(1st manufacturing method) As a method for producing a perovskite compound, a production method comprising the steps of dissolving Component B, Component X, and Component A constituting the perovskite compound in the above-mentioned dispersion medium (3) at a high temperature to obtain a solution can be exemplified. step; and the step of cooling the solution.

Hereinafter, the first manufacturing method will be specifically described.

First, a solution is obtained by dissolving the compound containing the B component and the X component and the compound containing the A component in a high temperature dispersion medium (3). The "compound containing component A" may also contain component X. In this step, each compound can also be added to the high temperature dispersion medium (3) and dissolved to obtain a solution. In addition, in this step, a solution can also be obtained by adding each compound to the dispersion medium (3) and then raising the temperature. In the first production method, the solution is preferably obtained by adding each compound to the first solvent and then raising the temperature.

The dispersion medium (3) is preferably a solvent that can dissolve the compound containing the B component and the X component and the compound containing the A component, which are raw materials.

The so-called "high temperature" may be a solvent at a temperature at which each raw material dissolves. For example, the temperature of the high temperature dispersion medium (3) is preferably 60 to 600°C, more preferably 80 to 400°C.

When a solution is obtained by adding each compound to the dispersion medium (3) and then raising the temperature, the holding temperature after raising the temperature is, for example, preferably 20 to 150°C, more preferably 120 to 140°C.

From the viewpoint of suppressing deterioration by removing unnecessary water after the reaction, it is preferable to carry out the reaction while flowing an inert gas.

Then, the obtained solution was cooled. As cooling temperature, -20-50 degreeC is preferable, and -10-30 degreeC is more preferable. As a cooling rate, 0.1-1500 degreeC/min is preferable, and 10-150 degreeC/min is more preferable.

By cooling the high-temperature solution, the perovskite compound can be precipitated by the difference in solubility due to the difference in temperature of the solution. Thereby, a dispersion liquid containing the perovskite compound is obtained.

The perovskite compound can be recovered by subjecting the dispersion liquid containing the obtained perovskite compound to solid-liquid separation. As a method of solid-liquid separation, filtration, concentration by evaporation of a solvent, etc. are mentioned. Only the perovskite compound can be recovered by performing solid-liquid separation.

Furthermore, in the above-mentioned production method, it is preferable to include the step of adding the above-mentioned surface modifier (6) in order to stably disperse the obtained particles of the perovskite compound in the dispersion liquid.

The step of adding the surface modifier (6) is preferably performed before the cooling step. Specifically, the surface modifier (6) may be added to the dispersion medium (3), or may be added to a solution obtained by dissolving the compound containing the B component and the X component and the compound containing the A component.

Moreover, in the above-mentioned production method, it is preferable to include the step of removing coarse particles by methods such as centrifugation and filtration after the cooling step. The size of the coarse particles removed by the removing step is preferably more than 10 μm, more preferably more than 1 μm, and still more preferably more than 500 nm.

(2nd manufacturing method) As a method for producing a perovskite compound, a production method including the following steps can be exemplified: a step of obtaining a first solution containing component A and component B constituting the perovskite compound; obtaining a solution containing component X constituting the perovskite compound The step of the second solution; the step of mixing the first solution and the second solution to obtain a mixed solution; and the step of cooling the obtained mixed solution.

Hereinafter, the second manufacturing method will be specifically described.

First, the compound containing the A component and the compound containing the B component are dissolved in a high-temperature second solvent to obtain a first solution. In this step, each compound may be added and dissolved in the high temperature dispersion medium (3) to obtain a first solution. In addition, in this step, the first solution may be obtained by adding each compound to the dispersion medium (3) and then raising the temperature. In the second production method, the first solution is preferably obtained by adding each compound to the dispersion medium (3) and then raising the temperature.

The dispersion medium (3) is preferably a solvent that can dissolve the compound containing the A component and the compound containing the B component.

The "high temperature" may be a temperature at which the compound containing the A component and the compound containing the B component dissolve. For example, the temperature of the high temperature dispersion medium (3) is preferably 60 to 600°C, more preferably 80 to 400°C.

When the first solution is obtained by adding each compound to the dispersion medium (3) and then raising the temperature, the holding temperature after the temperature rise is preferably, for example, 80 to 150°C, more preferably 120 to 140°C.

Moreover, the compound containing X component was melt|dissolved in the said dispersion medium (3), and the 2nd solution was obtained. The second solution may be obtained by dissolving the compound containing the X component and the compound containing the B component in the dispersion medium (3).

As a dispersion medium (3), the solvent which can dissolve the compound containing X component is mentioned.

Next, the obtained first solution and the second solution were mixed to obtain a mixed solution. When mixing the 1st solution and the 2nd solution, one can be added dropwise to the other. Moreover, the 1st solution and the 2nd solution may be mixed, stirring.

From the viewpoint of suppressing deterioration by removing unnecessary water after the reaction, it is preferable to carry out the reaction while flowing an inert gas.

Next, the obtained mixed liquid is cooled. As cooling temperature, -20-50 degreeC is preferable, and -10-30 degreeC is more preferable. As a cooling rate, 0.1-1500 degreeC/min is preferable, and 10-150 degreeC/min is more preferable.

By cooling the mixed solution, the perovskite compound can be precipitated by the difference in solubility due to the temperature difference of the mixed solution. Thereby, a dispersion liquid containing the perovskite compound is obtained.

The perovskite compound can be recovered by subjecting the dispersion liquid containing the obtained perovskite compound to solid-liquid separation. As a method of solid-liquid separation, the method shown in the 1st manufacturing method is mentioned.

Furthermore, in the above-mentioned production method, it is preferable to include the step of adding the above-mentioned surface modifier (6) in order to stably disperse the obtained particles of the perovskite compound in the dispersion liquid.

The step of adding the surface modifier (6) is preferably performed before the cooling step. Specifically, the surface modifier (6) can be added to any one of the dispersion medium (3), the first solution, the second solution, and the mixed solution.

Moreover, in the said manufacturing method, it is preferable to include the process of removing coarse particles by methods, such as centrifugation and filtration shown in the 1st manufacturing method, after a cooling process.

<Manufacture of luminescent composite particles> The luminescent composite particles are produced, for example, by contacting the perovskite compound particles with the hydrolyzable silicon compound (2), and optionally condensing the hydrolyzable silicon compound (2) to form a silicon compound layer on the surface of the perovskite compound particles. The contact between the perovskite compound particles and the hydrolyzable silicon compound (2) may also be performed in the presence of a dispersion medium (3). In this case, the dispersion medium (3) is removed after the above-mentioned particles are formed.

In the case of removing the dispersion medium (3), the dispersion liquid of the particles can be left to stand at room temperature for natural drying, can also be dried under reduced pressure using a vacuum dryer, or can be heated and dried by heating. For example, the dispersion medium (3) can be removed by drying at 0°C or higher and 300°C or lower for 1 minute or more and 7 days or less. In addition, the dispersion liquid of the said particle|grains containing a dispersion medium (3) can be used as it is as a luminescent composite particle composition after adjusting a density|concentration.

(Condensation treatment of hydrolyzable silicon compound (2)) The condensation treatment of the hydrolyzable silicon compound (2) can be performed by a known method such as a method in which the above-mentioned silazanes and the above-mentioned hydrolyzable silicon compound are reacted with water vapor. In the following description, the process of reacting the above-mentioned silazane and the above-mentioned hydrolyzable silicon compound with water vapor may be referred to as "humidification process". From the viewpoint of forming a stronger protection region in the vicinity of the perovskite compound particles, it is preferable to perform the humidification treatment.

In the case of carrying out the humidification treatment, for example, the luminescent composite particle composition may be allowed to stand for a certain period of time under the following temperature and humidity conditions, or may be stirred under the same conditions for a certain period of time.

The temperature during the humidification treatment may be a temperature at which condensation is sufficiently advanced. The temperature in the humidification treatment is, for example, preferably 5 to 150°C, more preferably 10 to 100°C, and still more preferably 15 to 80°C.

The humidity in the humidification treatment may be sufficient to supply moisture to the silazane and the hydrolyzable silicon compound in the particles. The humidity in the humidification treatment is, for example, preferably 30% to 100%, more preferably 40% to 95%, and still more preferably 60% to 90%.

The time required for the humidification treatment may be sufficient for condensation to proceed. The time required for the humidification treatment is, for example, preferably 10 minutes or more and 1 week or less, more preferably 1 hour or more and 5 days or less, and still more preferably 2 hours or more and 3 days or less.

The supply of water in the humidification treatment may be performed by circulating a gas containing water vapor in the reaction vessel, or by stirring in an environment containing water vapor, water may be supplied from the interface.

When the gas containing water vapor is circulated in the reaction vessel, in order to improve the durability of the obtained luminescent composite particle composition, the flow rate of the gas containing water vapor is preferably 0.01 L/min or more and 100 L/min Below, it is more preferable that it is 0.1 L/min or more and 10 L/min or less, and still more preferably 0.15 L/min or more and 5 L/min or less. As the gas containing water vapor, for example, nitrogen gas containing a saturated amount of water vapor can be mentioned.

4. Manufacturing method of luminescent composite particle composition The luminescent composite particle composition, that is, a mixture of the above-mentioned particles and a dispersion medium material can be produced, for example, by dispersing the above-mentioned particles in a dispersion medium material.

In the luminescent composite particle composition, the particles may be dispersed in a dispersion medium material, and the hydrolyzable silicon compound (2) may be added to the obtained dispersion to contact with the perovskite compound (1), and if necessary, hydrolyzed It is produced by condensing the silicone compound (2).

The light-emitting composite particle composition may polymerize the polymerizable compound (4) to make a part of the polymer (5). In this case, it is preferable that the sum total of particle|grains and polymer (5) is 90 mass % or more of the whole luminescent composite particle composition.

The step of polymerizing the polymerizable compound (4) can be performed by appropriately using a known polymerization reaction such as radical polymerization.

For example, in the case of radical polymerization, a radical polymerization initiator can be added to the mixture of the particle and the polymerizable compound (4) to generate radicals, thereby performing the polymerization reaction.

A radical polymerization initiator is not specifically limited, For example, a photoradical polymerization initiator etc. are mentioned.

As said photoradical polymerization initiator, bis(2,4,6-trimethylbenzyl)-phenylphosphine oxide etc. are mentioned, for example.

When the surface modifier (6) is used, the surface modifier (6) may be added together with the hydrolyzable silicon compound (2) after the perovskite compound particles are dispersed in the dispersion medium material.

5. Absorption rate, quantum yield and brightness maintenance rate of luminescent composite particles The absorbance and quantum yield of the luminescent composite particles can be measured using an absolute PL quantum yield measuring apparatus (for example, "C9920-02" (trade name) manufactured by Hamamatsu Photonics Co., Ltd.). In addition, the luminance maintenance ratio can be calculated according to the following formula using these values. In the present invention, the measurement is performed under the conditions of excitation light of 450 nm, 25° C., and 1 atmospheric pressure.

Brightness maintenance rate (%)=[(quantum yield of luminescent composite particle composition after light resistance test)÷(quantum yield of luminescent composite particle composition before light resistance test)]×[(luminescence after light resistance test Absorptivity of luminescent composite particle composition)÷(absorptivity of luminescent composite particle composition before light resistance test)]×100

The absorptivity of excitation light of the luminescent composite particles is preferably 0.1 or more and less than 1, more preferably 0.2 or more and less than 0.9, and still more preferably 0.3 or more and less than 0.9.

The quantum yield of the luminescent composite particles is preferably 0.1 to 1.0, more preferably 0.2 to 0.99, and still more preferably 0.3 to 0.95.

The luminance maintenance ratio of the luminescent composite particles is preferably 0.3 to 1.0, more preferably 0.5 to 1.0, and still more preferably 0.7 to 1.0. By making the luminance maintenance ratio into these ranges, a light-emitting particle material with high light resistance can be obtained.

6. Membrane The film of the present invention contains the luminescent composite particles of the present invention. For example, the film of the present invention includes luminescent composite particles and polymer (5). Typically, the total of the particles and the polymer (5) accounts for 90% by mass or more of the entire film.

The shape of the film is not particularly limited, and may be any shape such as a sheet shape or a rod shape. In the present specification, the "rod-like shape" means, for example, a band-like shape in plan view extending in one direction. As a belt-like shape in plan view, a plate-like shape in which the lengths of each side are different can be exemplified.

The thickness of the film may be, for example, 0.005 μm to 1000 mm, 0.01 μm to 10 mm, 0.1 μm to 1 mm, or 10 to 500 μm.

The film can be obtained, for example, by applying the liquid luminescent composite particle composition containing the dispersion medium (3) and the polymerizable compound (4) to obtain a coating film, and then applying the polymerizable compound contained in the coating film to the coating film. (4) Aggregation. The method for applying the liquid luminescent composite particle composition to the substrate is not particularly limited, and a gravure coating method, a bar coating method, a printing method, a spray method, a spin coating method, and a dipping method can be used. Coating is carried out by known coating and coating methods such as die coating method.

7. Laminated structures The laminated structure of the present invention has a plurality of layers, and at least one layer is the above-mentioned film. As a layer other than the said film among the several layers which a laminated structure has, arbitrary layers, such as a base material, a barrier rib layer, and a light-scattering layer, are mentioned. The shape of the layered film is not particularly limited, and may be any shape such as a sheet shape or a rod shape. In order to easily extract the light emitted by the perovskite compound (1), the substrate preferably has light transmittance. As a material for forming the base material, known materials such as polymers such as polyethylene terephthalate and glass can be used, for example.

A laminated structure can be manufactured by laminating|stacking the film obtained above on a base material, for example. In the step of laminating the films on the substrate, the films are bonded to each other using an adhesive. The adhesive is not particularly limited as long as the luminescent composite particles are not dissolved, and a known adhesive can be used for bonding.

8. Lighting device The light-emitting device of the present invention can be obtained by combining the above-described laminated structure with a light source. The light-emitting device is a device that emits light from the laminated structure by irradiating the laminated structure provided in the latter stage with light emitted from a light source and extracts the light. Examples of layers other than the above-mentioned film, base material, barrier layer, and light-scattering layer among the plurality of layers of the laminated structure in the above-mentioned light-emitting device include a light reflection member, a brightness enhancement portion, a sintered sheet, and a light guide plate. , any layer such as the dielectric material layer between components. As a specific example of the light-emitting device, for example, it is a light-emitting device in which a silicon wafer, a light guide plate, the above-mentioned laminated structure, and a light source are laminated in this order.

A light-emitting device can be manufactured, for example, by disposing the above-mentioned light source, and disposing the above-mentioned laminated structure on the light path from the light source.

9. Display The display of the present invention includes, for example, a liquid crystal display formed by laminating a liquid crystal panel, a wafer, a light guide plate, the above-mentioned laminated structure, and a light source in this order. The display can be manufactured by laminating a display element including a polarizing plate or the like on the above-mentioned light-emitting device.

10. Blinker The luminescent composite particles or the luminescent composite particle composition can be used as a scintillator for an imaging device for X-ray images or a brightness enhancement film. It does not specifically limit as a form of a scintillator, For example, it can utilize in arbitrary forms, such as a single crystal and a sheet.

When the scintillator is used in the form of a sheet, it can be produced by coating the liquid luminescent composite particle composition containing the luminescent composite particles on a substrate and drying it. The substrate to be used is not particularly limited, for example, aluminum metal, PET film, moth-eye film, etc. can be used. The scintillator can also be used in combination with other commercially available scintillators.

3 is a cross-sectional view schematically showing the structure of an X-ray detector including the scintillator of the present invention. The X-ray detector 1 includes a scintillator panel 2 , an output substrate 3 , and a power supply unit 12 .

The scintillator panel 2 has a substrate 5 and a scintillator layer 4 . The scintillator layer 4 includes the film of the present invention described above. The film contains the luminescent composite particles 100 and the polymer 6 .

The output substrate 3 has the photoelectric conversion layer 8 and the output layer 9 on the substrate 11 . The photoelectric conversion layer 8 is usually formed by two-dimensionally forming pixels having photo sensors and TFTs (not shown). The photoelectric conversion layer 8 may also have a diaphragm layer 7 thereon. Preferably, the light-emitting surface of the scintillator panel 2 and the photoelectric conversion layer 8 of the output substrate 3 are bonded or tightly bonded through the diaphragm layer 7 .

The light emitted by the scintillator layer 4 reaches the photoelectric conversion layer 8 and is photoelectrically converted and output. As for the materials constituting the X-ray detector, those previously known can be used except for the scintillator layer 4 . For example, the structure and constituent material of an X-ray detector including a scintillator are described in Patent Document 2, and the structure and constituent material of the X-ray detector described in Patent Document 2 can be used in the present invention. [Example]

Hereinafter, the present invention will be described more specifically based on Examples and Comparative Examples. The present invention is not limited to the following examples.

<Measurement and Evaluation> Regarding the luminescent composite particles obtained in the following Examples and Comparative Examples, the following items were measured and evaluated according to the following methods.

(Particle size of perovskite compound particles) The particles of the perovskite compound (1) were photographed using a transmission electron microscope (“JEM-2200FS” (trade name) manufactured by JEOL Ltd.), and the average particle size ( average Ferret diameter). In the calculation, the interval between the parallel lines sandwiching the particles by two parallel lines was set as the Ferret diameter, and the arithmetic mean of the Ferret diameters of 50 particles was calculated. The sample is obtained by collecting perovskite compound particles from the self-luminous composite particle composition and placing them in a grid with a support film. The measurement conditions were set to an accelerating voltage of 200 kV.

(Particle size of luminescent composite particles) The average particle diameter of the luminescent composite particles was measured using a particle size analyzer (“Zetasizer Nano ZS” (trade name) manufactured by Malvern Corporation). As a measurement method, a dynamic light scattering method was used. The obtained luminescent composite particles were evenly distributed in number, and the average particle diameter and standard deviation σ were obtained. The measurement sample is measured by dropping the dispersion into a specific container (glass).

(quantum yield, absorption rate) The quantum yields of the luminescent composite particle compositions obtained in Examples 1, 2, 3 and Comparative Example 1 were measured using an absolute PL quantum yield analyzer (“C9920-02” (trade name) manufactured by Hamamatsu Photonics Co., Ltd.) yield and absorption. The measurement was performed before and after the following light irradiation, and the measurement conditions were set to excitation light of 450 nm, 25° C., and 1 atmosphere.

(Evaluation of light resistance) 100 μL of the luminescent composite particle compositions obtained in Examples 1, 2, 3 and Comparative Example 1 were coated on a glass substrate with a size of 1 cm×1 cm, and allowed to dry naturally film is obtained. While heating the obtained film to 50° C., irradiated with light with a peak wavelength of 450 nm and an illuminance of 100 mW/cm ² from an LED (light-emitting diode) light source for 48 hours.

From the quantum yield and absorptivity of the luminescent composite particle composition before and after light irradiation, the luminance maintenance rate was calculated|required based on the following formula. Regarding the luminance maintenance ratio, the higher the value, the higher the light resistance can be evaluated. In addition, the evaluation was performed with respect to the latter after 48 hours of light irradiation.

Brightness maintenance rate (%)=[(quantum yield of luminescent composite particle composition after light resistance test)÷(quantum yield of luminescent composite particle composition before light resistance test)]×[(luminescence after light resistance test Absorptivity of luminescent composite particle composition)÷(absorptivity of luminescent composite particle composition before light resistance test)]×100

[Example 1] (Production of Perovskite Compound Particles) After mixing 25 mL of oleylamine and 200 mL of ethanol, the mixture was stirred with ice cooling, and 17.12 mL of an aqueous hydrobromic acid solution (48%) was added, followed by drying under reduced pressure to obtain a precipitate. After the precipitate was washed with diethyl ether, it was dried under reduced pressure to obtain oleylammonium bromide.

200 mL of toluene was mixed with 21 g of oleyl ammonium bromide to prepare a solution containing oleyl ammonium bromide.

1.52 g of lead acetate trihydrate, 1.56 g of formamidine acetate, 160 mL of a solvent for 1-octadecene, and 40 mL of oleic acid were mixed. While stirring under a nitrogen atmosphere and heating to 130°C, 53.4 mL of the above solution containing oleyl bromide was added. After the addition, the solution was cooled to room temperature to obtain a dispersion liquid containing the perovskite compound (1).

To 200 mL of the above dispersion liquid were mixed 100 mL of toluene and 100 mL of ethyl acetate, followed by filtration for solid-liquid separation. Then, the solid content on the filter paper was washed twice with a mixed solution of 100 mL of toluene and 100 mL of ethyl acetate, followed by filtration. Thereby, the perovskite compound particles are isolated.

(Manufacture of luminescent composite particle composition) Next, using toluene as a dispersion medium, 150 mL of dispersion liquids were prepared so that the density|concentration of perovskite compound particle might become 0.34 mass %. Organopolysilazane (1500 Slow Cure, Durazane, manufactured by Merck Performance Materials Co., Ltd.) was added thereto in an amount of 2.0 parts by mass relative to 1 part by mass of the perovskite compound. Then, the condensation treatment by water vapor was performed for 4 hours, and it was left to stand for 0.5 hours under a nitrogen atmosphere after drying. The condensation treatment was carried out under the steam flow rate: 0.4 L/min (supplied together with nitrogen gas (N ₂ ), the amount of saturated steam at 30°C) and the heating temperature: 90°C. The dispersion liquid after the condensation treatment was filtered with a 0.5 μm membrane filter to obtain a luminescent composite particle composition. The obtained luminescent composite particle composition was subjected to DLS measurement, and the average particle diameter of the particles was estimated. The average particle size was 27.26 nm ± 8.5. The luminance maintenance rate after the light resistance test was 70.1%.

[Example 2] In the production step of the luminescent composite particles, the dispersion liquid of the perovskite compound particles was set from 150 mL to 30 mL, and the gas flow rate during the condensation treatment was set to 0.08 L/min. 1 The same method was used to obtain the luminescent composite particle composition. If the average particle size of the particles is estimated in the same way, it is 26.54 nm ± 5.4. In addition, the luminance maintenance ratio was 78.0%.

[Example 3] In the production step of the luminescent composite particles, after adding the organopolysilazane, 0.25 parts by mass of trimethoxy (1H, 1H, 2H, 2H-nonafluorohexyl) was further added with respect to 1 part by mass of the organopolysilazane. ) silane (manufactured by Tokyo Chemical Industry Co., Ltd.), a luminescent composite particle composition was obtained in the same manner as in Example 2 above. If the average particle size of the particles is estimated by the same method, it is 17.59 nm±5.2. In addition, the luminance maintenance rate was 100%.

[Comparative Example 1] The luminescent composite particle composition was obtained by the same method except not filtering the obtained luminescent composite particle composition with a membrane filter in the manufacturing process of the luminescent composite particle described in Example 1. If the average particle size of the particles is estimated by the same method, it is 495.2 nm ± 142.0. In addition, the luminance maintenance rate was 24.8%.

In the light-emitting composite particles of Examples 1 to 3 and Comparative Example 1, the above measurements were performed. The results are shown in Table 1.

[Table 1] Brightness maintenance rate (%) Average particle size (nm) Standard Deviation (nm) Example 1 70.1 27.26 8.426 Example 2 78.0 26.54 5.374 Example 3 100 17.59 5.177 Comparative example 24.8 495.2 142.0

From the above results, it was confirmed that the luminescent composite particles of Examples 1 to 3 including the perovskite compound having an average particle diameter of 1 to 100 nm were superior in light resistance as compared with the luminescent composite particles of Comparative Example 1.

[Reference Example 1] After putting the luminescent composite particle compositions described in Examples 1 to 3 in a glass tube or the like and sealing, it was placed between a blue light-emitting diode as a light source and a light guide plate to produce a A backlight device that converts blue light from blue light-emitting diodes into green or red light.

[Reference Example 2] The luminescent composite particle compositions described in Examples 1 to 3 were sheeted to obtain a resin composition, and the resin composition was sandwiched between two barrier films and sealed to obtain a film, and the obtained The film is arranged on the light guide plate, thereby producing a backlight that can convert the blue light irradiated to the above-mentioned sheet from the blue light-emitting diodes arranged on the end face (side surface) of the light guide plate through the light guide plate into green light or red light device.

[Reference Example 3] The light-emitting composite particle compositions described in Examples 1 to 3 were placed near the light-emitting portion of the blue light-emitting diode, thereby producing a backlight device capable of converting irradiated blue light into green light or red light.

[Reference Example 4] After mixing the light-emitting composite particle compositions described in Examples 1 to 3 with a resist, and removing the solvent, a wavelength conversion material can be obtained. The obtained wavelength conversion material is set between the blue light emitting diode as the light source and the light guide plate or the latter part of the OLED (organic light emitting diode, organic light emitting diode) as the light source, thereby manufacturing the light source A backlight device that converts blue light into green light or red light.

[Reference Example 5] The luminescent composite particle compositions described in Examples 1 to 3 were mixed with conductive particles such as ZnS to form a film, an n-type transport layer was layered on one area, and a p-type transport layer was layered on the other area to obtain an LED. By flowing a current, the holes of the p-type semiconductor and the electrons of the n-type semiconductor cancel the charges in the perovskite compound of the junction surface, thereby enabling the LED to emit light.

[Reference Example 6] A dense layer of titanium oxide was deposited on the surface of a fluorine-doped tin oxide (FTO) substrate, a porous alumina layer was deposited thereon, and the luminescent composite particle compositions described in Examples 1 to 3 were deposited thereon. , and after the solvent was removed, 2,2',7,7'-tetra-(N,N'-di-p-methoxyaniline)-9,9'-spiro-OMe A hole transport layer such as TAD), on which a silver (Ag) layer is laminated to make a solar cell.

[Reference Example 7] The composition of the present embodiment can be obtained by post-molding a solvent containing the composition of the luminescent composite particles described in Examples 1 to 3, and it is placed in the latter stage of the blue light-emitting diode to produce the composition of the present embodiment. Laser diode illumination that emits white light from the blue light emitting diode irradiated to the composition after the blue light is converted into green light or red light.

[Reference Example 8] The composition of the present embodiment can be obtained by removing the solvent of the composition containing the luminescent composite particles described in Examples 1 to 3 and molding. The obtained composition is used as a part of the photoelectric conversion layer, whereby a photoelectric conversion element (photodetection element) material used and included in the detection part of the detection light is produced. Photoelectric conversion element materials are used for detection of living bodies in the image detection section (image sensor), fingerprint detection section, face detection section, vein detection section, and iris detection section for solid-state imaging devices such as X-ray imaging devices and CMOS image sensors. Optical biosensors such as the detection part of a part of specific features, pulse oximeter, etc.

[Reference Example 9] The composition of the present embodiment can be obtained by removing the solvent of the composition containing the luminescent composite particles described in Examples 1 to 3 and molding. The obtained composition can be used as a film for improving the light conversion efficiency of solar cells. It does not specifically limit as a form of the said conversion efficiency improvement sheet, It can utilize in the form of apply|coating to a base material. The base material is not particularly limited as long as it is a base material with high transparency. For example, a PET film, a moth-eye film, or the like is preferable. The solar cell using the solar cell conversion efficiency improvement sheet is not particularly limited, and the conversion efficiency improvement sheet has the function of converting from a wavelength region with a lower sensitivity of the solar cell to a wavelength region with a higher sensitivity.

[Reference Example 10] The composition of this embodiment can be obtained by shaping|molding after removing the solvent of the composition containing the luminescent composite particle of Examples 1-3. The obtained composition can be used as a light source for generating single photons such as quantum computers, quantum televisions, and quantum encrypted communications.

1: X-ray detector 2: Scintillation panel 3: Output substrate 4: scintillator layer 5: Substrate 6: Polymer 7: Diaphragm layer 8: Photoelectric conversion layer 9: Output layer 10: Perovskite Compound Particles 11: Substrate 12: Power Department 20: Silicon compound layer 30: Dispersion medium material 100: luminescent composite particles 200: Luminescent composite particle composition

FIG. 1 is a cross-sectional view schematically showing the structure of the luminescent composite particle of the present invention. Fig. 2 is a cross-sectional view schematically showing the structure of the luminescent composite particle composition of the present invention. 3 is a cross-sectional view schematically showing the structure of an X-ray detector including the scintillator of the present invention.

10: Perovskite Compound Particles

20: Silicon compound layer

100: luminescent composite particles

Claims (9)

A luminescent composite particle having perovskite compound particles and a silicon compound layer formed on at least a part of the surface of the perovskite compound particles, and having an average particle size of 1 to 100 nm, the perovskite compound particles having Perovskite crystal structure with A, B and X as constituents [In the perovskite crystal structure, A is a component located at each vertex of the hexahedron with B as the center, and is a monovalent cation, B is a component located at the center of the hexahedron with A placed at the vertex and the octahedron with X placed at the vertex, and is a metal ion, X is a component located at each vertex of the octahedron with B as the center, and is at least one anion selected from the group consisting of a halide ion and a thiocyanate ion], and has luminescence. The luminescent composite particle according to claim 1, wherein the silicon compound layer comprises at least one layer selected from the group consisting of a hydrolyzable silicon compound and a condensate thereof. The luminescent composite particle according to claim 1 or 2, wherein the above-mentioned luminescent perovskite compound particle has a primary particle diameter of 1 to 80 nm. A luminescent composite particle composition comprising the luminescent composite particle according to any one of claims 1 to 3, and at least one selected from the group consisting of a dispersion medium, a polymerizable compound, and a polymer. A film comprising the luminescent composite particles as claimed in any one of claims 1 to 3. A laminated structure comprising the film of claim 5. A light-emitting device including the laminated structure as claimed in claim 6. A display provided with the laminated structure as claimed in claim 6. A scintillator comprising the luminescent composite particles of any one of claims 1 to 3.

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