WO2022044907A1

WO2022044907A1 - Light-emitting composite particles and light-emitting composite particle composition

Info

Publication number: WO2022044907A1
Application number: PCT/JP2021/030149
Authority: WO
Inventors: 瑞穂杉内; 翔太内藤
Original assignee: 住友化学株式会社
Priority date: 2020-08-27
Filing date: 2021-08-18
Publication date: 2022-03-03
Also published as: TW202212455A; JP2022038930A; CN115989193A

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

Luminous composite particles and luminescent composite particle composition

The present invention relates to particles of a semiconductor compound having light emission, and particularly to particles of a perovskite type semiconductor compound having light emission.

A perovskite-type semiconductor compound (hereinafter referred to as "perovskite compound") is a luminescent semiconductor compound having a high quantum yield, and is attracting attention as a luminescent material. For example, Patent Document 1 describes a luminescent film using a perovskite compound as a luminescent material. The luminescent film of Patent Document 1 has a sea-island structure in which luminescent perovskite compound particles have an island portion which is a particle contained in a silazane modifier and a sea portion which is a polymer. The luminescent film of Patent Document 1 is a luminescent material having excellent durability against water vapor.

International Publication No. 2018/21268 International Publication No. 2019/131370

On the other hand, it has been clarified that the luminescent film of Patent Document 1 tends to be deteriorated by irradiation with excitation light, and the luminance maintenance rate (maintenance rate of quantum yield × maintenance rate of absorption rate) tends to decrease. .. Therefore, the luminescent film of Patent Document 1 still has room for improvement in terms of light resistance.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a luminescent particle material containing a perovskite compound, which has excellent light resistance.

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

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

In one form, the luminescent perovskite compound particles have a primary particle diameter of 1-80 nm.

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

The present invention also provides a film containing any of the above-mentioned luminescent composite particles.

The present invention also provides a laminated structure containing the film.

The present invention also provides a light emitting device provided with the laminated structure.

The present invention also provides a display provided with the laminated structure.

The present invention also provides a scintillator containing any of the above-mentioned luminescent composite particles.

According to the present invention, it is possible to provide a luminescent particle material containing a perovskite compound, which has excellent light resistance.

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. FIG. 3 is a cross-sectional view schematically showing the structure of an X-ray detector including the scintillator of the present invention.

1. 1. Luminescent Composite Particles Containing Perovskite Compounds FIG. 1 is a cross-sectional view schematically showing the structure of the luminescent composite particles of the present invention. The luminescent composite particle 100 has a perovskite compound particle 10 and a silicon compound layer 20 formed on the surface thereof. It is sufficient that the silicon compound layer 20 is formed on at least a part of the surface of the perovskite compound particles 10.

<Perovskite compound particles>
The perovskite compound particle 10 is 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, hereinafter referred to as “perovskite compound (1)”. It is a particle consisting of.). The structure of the perovskite compound (1) may be any of a three-dimensional structure, a two-dimensional structure, and a pseudo two-dimensional (quasi-2D) structure.
In the case of a three-dimensional structure, the composition 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) is electrically neutral. can. 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) contains an octahedron centered on B and having an apex X. The octahedron is represented by BX ₆ .
When the perovskite compound (1) has a three-dimensional structure, the BX ₆ contained in the perovskite compound (1) has one X located at the apex of the octahedron (BX ₆ ) and two octahedrons adjacent to each other in the crystal. By sharing with (BX ₆ ), a three-dimensional network is configured.

When the perovskite compound (1) has a two-dimensional structure, the BX ₆ contained in the perovskite compound (1) has two Xs located at the vertices of the octahedron (BX ₆ ) and two octahedrons adjacent to each other in the crystal. By sharing with (BX ₆ ), the ridgeline of the octahedron is shared to form a two-dimensionally connected layer. The perovskite compound (1) has a structure in which a layer made of BX ₆ and a layer made of A, which are two-dimensionally connected, are alternately laminated.

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

(Component A)
A constituting the perovskite compound (1) is a monovalent cation. Examples of A include cesium ion, organic ammonium ion, and amidinium ion.

(Organic ammonium ion)
Specific examples of the organic ammonium ion of A include a cation represented by the following formula (A3).

In the formula (A3), R ⁶ to R ⁹ 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 not all of R ⁶ to R ⁹ become hydrogen atoms at the same time.

The alkyl group represented by R ⁶ to R ⁹ may be linear or branched. Further, the alkyl groups represented by R ⁶ to R ⁹ may 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 1 respectively. Is even more preferable.

The cycloalkyl groups represented by R ⁶ to R ⁹ may 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, and more preferably 3 to 8, respectively. The number of carbon atoms includes the number of carbon atoms of the substituent.

The groups represented by R ⁶ to R ⁹ are preferably hydrogen atoms or alkyl groups independently of each other.

When the perovskite compound (1) contains an organic ammonium ion represented by the above formula (A3) as A, the number of alkyl groups and cycloalkyl groups that can be contained in the formula (A3) is preferably small. Further, the number of carbon atoms of the alkyl group and the cycloalkyl group that can be contained in the formula (A3) is preferably small. This makes it possible to obtain a perovskite compound (1) having a three-dimensional structure having high emission intensity.

In the organic ammonium ion represented by the formula (A3), the total number of carbon atoms contained in the alkyl group represented by R ⁶ to R ⁹ and the cycloalkyl group is preferably 1 to 4.
Further, in the organic ammonium ion represented by the formula (A3), 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. It is more preferable to have.

The alkyl groups of R ⁶ to R ⁹ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group and isopentyl group. , Neopentyl group, tert-pentyl group, 1-methylbutyl group, n-hexyl group, 2-methylpentyl group, 3-methylpentyl group, 2,2-dimethylbutyl group, 2,3-dimethylbutyl group, n-heptyl Group, 2-methylhexyl group, 3-methylhexyl group, 2,2-dimethylpentyl group, 2,3-dimethylpentyl group, 2,4-dimethylpentyl group, 3,3-dimethylpentyl group, 3-ethylpentyl Group, 2,2,3-trimethylbutyl group, n-octyl group, isooctyl group, 2-ethylhexyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl Examples thereof include a group, an octadecyl group, a nonadecyl group, and an icosyl group.

Examples of the cycloalkyl groups of R ⁶ to R ⁹ include those obtained by independently forming a ring of alkyl groups having 3 or more carbon atoms exemplified by the alkyl groups of R ⁶ to R ⁹ . As an example, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, norbornyl group, isobornyl group, 1-adamantyl group, 2-adamantyl group, tricyclodecyl group. Etc. can be exemplified.

Organic ammonium ions represented by A include CH ₃ NH ₃₊ (also referred to as methylammonium ion) _, _{C2H 5} _NH ³⁺ ⁽ also referred to as _{ethylammonium} ion) or C3 _H7 NH ₃₊ (propyl) ^. It is also preferably ammonium ion), more preferably methylammonium ion or ethylammonium ion, and even more preferably methylammonium ion.

(Amidinium ion)
Examples of the amidinium ion represented by A include the amidinium ion represented by the following formula (A4).

(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 be independently linear or branched. Further, the alkyl groups represented by R ¹⁰ to R ¹³ may independently have an amino 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 independently, preferably 1 to 4, and more preferably 1 to 3.

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

The number of carbon atoms of the cycloalkyl group represented by R ¹⁰ to R ¹³ is usually 3 to 30, preferably 3 to 11, and more preferably 3 to 8, respectively. 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 in 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 in R ⁶ to R ⁹ , respectively.

As the group represented by R ¹⁰ to R ¹³ , a hydrogen atom or an alkyl group is preferable independently.

By reducing the number of alkyl groups and cycloalkyl groups contained in the formula (A4) and reducing the number of carbon atoms of the alkyl groups and cycloalkyl groups, the perovskite compound (1) having a three-dimensional structure with high emission intensity ) Can be obtained.

In the amidinium ion, the total number of carbon atoms contained in the alkyl group represented by R ¹⁰ to R ¹³ and the cycloalkyl group is preferably 1 to 4, and R ¹⁰ is an alkyl group having 1 carbon atom. It is more preferable that R ¹¹ to R ¹³ are hydrogen atoms.

In the perovskite compound (1), when A 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 a three-dimensional structure. Have.

In the perovskite compound (1), when A 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 pseudo two-dimensional (quasi-). 2D) Has one or both of the structures. In this case, the perovskite compound (1) can have a two-dimensional structure or a pseudo two-dimensional structure in a part or the whole of the crystal.
When a plurality of two-dimensional perovskite-type crystal structures are laminated, they become equivalent to a three-dimensional perovskite-type crystal structure (references: P. PBoix et al., J. Phys. Chem. Lett. 2015, 6, 898-907, etc.).

As A in the perovskite compound (1), cesium ion or amidinium ion is preferable, and amidinium ion is more preferable.

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

(Component B)
B constituting the perovskite compound (1) may be one or more kinds of metal ions selected from the group consisting of monovalent metal ions, divalent metal ions, and trivalent metal ions. B preferably contains a divalent metal ion, more preferably one or more metal ions selected from the group consisting of lead ion, tin ion, antimony ion, bismuth ion, and indium ion, and more preferably lead ion or tin ion. Is more preferable, and lead ion is particularly preferable.

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

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

Examples of the halide ion include chloride ion, bromide ion, fluoride ion, and iodide ion. 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 kinds of halide ions, the content ratio of the halide ions can be appropriately selected depending on the emission wavelength. For example, it can be a combination of a bromide ion and a chloride ion, or a combination of a bromide ion and an iodide ion.

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

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 480 nm or more, preferably 500 nm or more, more preferably 520 nm or more.

Further, 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, more preferably 580 nm or less.
The upper limit value and the lower limit value of the above 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 to 700 nm, preferably 500 to 600 nm, and more preferably 520 to 580 nm.

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

Further, the perovskite compound (1) in which X is an iodide ion can emit fluorescence having a maximum intensity peak in a wavelength range of usually 800 nm or less, preferably 750 nm or less, more preferably 730 nm or less.
The upper limit value and the lower limit value of the above 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 to 800 nm, preferably 530 to 750 nm, and more preferably 540 to 730 nm.

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

Further, the perovskite compound (1) in which X is a chloride ion can emit fluorescence having a maximum intensity peak in a wavelength range of usually 600 nm or less, preferably 580 nm or less, more preferably 550 nm or less.
The upper limit value and the lower limit value of the above 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 to 600 nm, preferably 310 to 580 nm, and more preferably 330 to 550 nm.

(Example of perovskite compound (1) having a three-dimensional structure)
Preferred examples of the perovskite compound (1) having a three-dimensional structure represented by ABX _{(3 + δ)} are CH ₃ NH ₃ PbBr ₃ , CH ₃ NH ₃ PbCl ₃ , CH ₃ NH ₃ PbI ₃ , and CH ₃ NH ₃ PbBr ₍ CH 3 NH 3 PbBr 3). _3-y) I _y (0 <y <3), CH ₃ NH ₃ PbBr _(3-y) _Cly (0 <y <3), (H ₂ N = CH-NH ₂ ) PbBr ₃ , (H ₂ ) N = CH-NH ₂ ) PbCl ₃ and (H ₂ N = CH-NH ₂ ) PbI ₃ can be mentioned.

Preferred examples of the perovskite compound (1) having a three-dimensional structure include CH ₃ NH ₃ Pb _(1-a) Ca _a Br ₃ (0 <a ≦ 0.7) and 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) can also be mentioned.

Preferred examples of the perovskite compound (1) having a three-dimensional structure 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) can also be mentioned.

Preferred examples of the perovskite compound (1) having a three-dimensional structure include CsPb _(1-a) Na _a Br _{(3 + δ)} (0 <a ≦ 0.7, −0.7 ≦ δ <0), CsPb _(1- a). _a) Li _a Br _{(3 + δ)} (0 <a ≦ 0.7, −0.7 ≦ δ <0) can also be mentioned.

A preferred example of the perovskite compound (1) having a three-dimensional structure is 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)} _Cly (0 <a≤0.7, -0.7≤δ <0,0 <y <3), CH ₃ NH ₃ Pb _(1-a) Li _a Br _{(3 + δ-y)} _Cly (0 <a≤0.7, -0.7≤δ <0,0 <y <3) can also be mentioned.

A preferred example of the perovskite compound (1) having a three-dimensional structure is (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)} _Cly (0 <a≤0.7, -0.7≤δ <0,0 <y <3) is also mentioned. be able to.

Preferred examples of the perovskite compound (1) having a three-dimensional structure include CsPbBr ₃ , CsPbCl ₃ , CsPbI ₃ , CsPbBr _(3-y) I _y (0 <y <3), and CsPbBr _(3-y) _Cly (0). <Y <3) can also be mentioned.

Preferred examples of the perovskite compound (1) having a three-dimensional structure include CH ₃ NH ₃ Pb _(1-a) Zn _a Br ₃ (0 <a ≦ 0.7) and 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) can also be mentioned.

Preferred examples of the perovskite compound (1) having a three-dimensional structure 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) can also be mentioned.

A preferred example of the perovskite compound (1) having a three-dimensional structure is 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) _Cly (0 <a≤0.7, 0 <y <3), CH ₃ NH ₃ Pb _(1-a) Al _a Br _{(3 + δ-y)} _Cly (0 <a≤0.7, 0 <δ≤0.7, 0 <y <3), CH ₃ NH ₃ Pb _(1-a) Co _a Br _{(3 + δ-y} ) ₎ Cly (0 <a≤0.7, 0 < _y <3), CH ₃ NH ₃ Pb _(1-a) Mn _a Br _(3-y) _Cly (0 <a≤0.7, 0 < y <3), CH ₃ NH ₃ Pb _(1-a) Mg _a Br _(3-y) _Cly (0 <a ≦ 0.7, 0 <y <3) can also be mentioned.

Preferred examples of the perovskite compound (1) having a three-dimensional structure 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) _Cly (0 <a≤0.7, 0 <y <3) can also be mentioned. can.

Among the above-mentioned three-dimensionally structured perovskite compounds (1), CsPbBr ₃ , CsPbBr _(3-y) Iy (0 < _y < _{3), and (H2N = CH-NH 2) PbBr 3} _are _more preferable. H ₂ N = CH-NH ₂ ) PbBr ₃ is more preferable.

(Example of perovskite compound (1) having a two-dimensional structure)
Preferred examples of the perovskite compound (1) having a two-dimensional structure are (C ₄ H ₉ NH ₃ ) ₂ PbBr ₄ , (C ₄ H ₉ NH ₃ ) ₂ PbCl ₄ , (C ₄ H ₉ NH ₃ ) ₂ PbI ₄ , (C ₇ H ₁₅ NH ₃ ) ₂ PbBr ₄ , (C ₇ H ₁₅ NH ₃ ) ₂ PbCl ₄ , (C ₇ H 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) can be mentioned.

Preferred examples of the perovskite compound (1) having a two-dimensional structure include (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) Rba _a Br _{(4 + δ)} (0 <a ≦ 0.7, −0.7 ≦ δ <0) can also be mentioned.

Preferred examples of the perovskite compound (1) having a two-dimensional structure include (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) Rba _a Br _{(4 + δ-y)} I _y (0 <a ≤ 0.7,- 0.7 ≦ δ <0, 0 <y <4) can also be mentioned.

A preferred example of the perovskite compound (1) having a two-dimensional structure is (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Na _a Br _{(4 + δ-y)} _Cly (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)} _Cly (0 <a ≤ 0.7,- 0.7 ≦ δ <0, 0 <y <4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Rba _a Br _{(4 + δ-y)} _Cly (0 <a ≦ 0.7,- 0.7 ≦ δ <0, 0 <y <4) can also be mentioned.

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

Preferred examples of the two-dimensional structure perovskite compound (1) are (C ₄ H ₉ NH ₃ ) ₂ PbBr _(4-y) _Cly (0 <y <4), (C ₄ H ₉ NH ₃ ) ₂ PbBr. _(4-y) I _y (0 <y <4) can also be mentioned.

Preferred examples of the perovskite compound (1) having a two-dimensional structure 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) ), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Mn _a Br ₄ (0 <a ≦ 0.7) can also be mentioned.

Preferred examples of the perovskite compound (1) having a two-dimensional structure 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) ), (C ₇ H ₁₅ NH ₃ ) ₂ Pb _(1-a) Mn _a Br ₄ (0 <a ≦ 0.7) can also be mentioned.

Preferred examples of the perovskite compound (1) having a two-dimensional structure include (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) can also be mentioned.

A preferred example of the perovskite compound (1) having a two-dimensional structure is (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Zn _a Br _(4-y) _Cly (0 <a ≤ 0.7, 0). <Y <4), (C ₄ H ₉ NH ₃ ) ₂ Pb _(1-a) Mg _a Br _(4-y) _Cly (0 <a ≤ 0.7, 0 <y <4), (C ₄ ) H ₉ NH ₃ ) ₂ Pb _(1-a) Co _a Br _(4-y) _Cly (0 <a ≤ 0.7, 0 <y <4), (C ₄ H ₉ NH ₃ ) ₂ Pb ₍₁ ) -A ₎ Mn _a Br _(4-y) _Cly (0 <a≤0.7, 0 <y <4) can also be mentioned.

<Primary particle size of perovskite compound particles>
In the present specification, the primary particle size of the perovskite compound particles is the average particle size of the perobskite compound particles in the mixture of the perobskite compound particles composed of a plurality of perobskite compound particles, and the average particle size thereof is 1.0 to 1. It is preferably 80.0 nm or less. From the viewpoint that the luminescent composite particles can be stably dispersed in the dispersion medium, the average particle size of the perovskite compound particles is preferably 3.0 nm or more, more preferably 5.0 nm or more, and more preferably 10.0 nm or more. Is more preferable. Further, from the viewpoint of obtaining luminescent composite particles having high luminescence intensity, the average particle size of the perovskite compound particles is preferably 50.0 nm or less, more preferably 30.0 nm or less, and 20.0 nm or less. Is even more preferable.

The average particle size of the perovskite compound particles can be measured by observing with, 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 length of the longest side of cube-shaped or rectangular parallelepiped-shaped particles of 30 or more randomly selected perovskite compound particles is measured, and the arithmetic mean value of the measured values is calculated. By doing so, the average particle size can be obtained.

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

<Silicon compound layer>
The silicon compound layer 20 is a layer composed of at least one compound selected from the group consisting of a hydrolyzable silicon compound and a condensate thereof. The hydrolyzable silicon compound is a silicon compound having a hydrolyzable functional group, which is condensed to form a Si—O—Si bond. "Condensation" means that a silicon compound having a Si—N bond, a Si—SR bond (R is a hydrogen atom or an organic group) or a Si—OR bond (R is a hydrogen atom or an organic group) is hydrolyzed and Si—O. -It means that a silicon compound having a Si bond is produced. The Si—O—Si bond may be formed by an intermolecular condensation reaction or an intramolecular condensation reaction.

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

<Shirazan>
Cilazan is a compound having a Si—N—Si bond. Cilazan may be linear, branched, or cyclic.

The shirazan may be a small molecule shirazan or a high molecular weight shirazan. In the present specification, the polymer silazane may be referred to as polysilazane.

As used herein, the term "small molecule" means that the number average molecular weight is less than 600.
Further, in the present specification, the term "polymer" means that the number average molecular weight is 600 or more and 2000 or less.

As used herein, the term "number average molecular weight" means a polystyrene-equivalent value measured by a gel permeation chromatography (GPC) method.

(Small molecule silazan)
As the small molecule silazane, for example, disilazane represented by the following formula (B1) is preferable.

In the formula (B1), R ¹⁴ and R ¹⁵ are independently hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 1 to 20 carbon atoms, and a cycloalkyl having 3 to 20 carbon atoms. It represents a group, an aryl group having 6 to 20 carbon 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 ^15s may be the same or different.

Examples of the small molecule silazane represented by the formula (B1) include 1,3-divinyl-1,1,3,3-tetramethyldisilazane, 1,3-diphenyltetramethyldisilazane, and 1,1,1. Examples thereof include 3,3,3-hexamethyldisilazane.

(Small molecule silazan)
As the small molecule silazane, for example, a small molecule silazane represented by the following formula (B2) is also preferable.

In the 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 ^14s may be the same or different.
The plurality of R ^15s may be the same or different.

In equation (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.

Examples of the small molecule silazane represented by the formula (B2) include octamethylcyclotetrasilazane, 2,2,4,4,6,6-hexamethylcyclotrisilazane, and 2,4,6-trimethyl-2,4. , 6-Trivinylcyclotrisilazane.

As the small molecule silazane, octamethylcyclotetrasilazane and 1,3-diphenyltetramethyldisilazane are preferable, and octamethylcyclotetrasilazane is more preferable.

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

Polysilazane is a polymer compound having a Si—N—Si bond. The constituent unit of polysilazane represented by the formula (B3) may be one kind or a plurality of kinds.

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

In equation (B3), * represents a bond. ^R14 is bonded to the bond of the N atom at the end of the molecular chain.
^R15 is bonded to the bond of the Si atom at the end of the molecular chain.

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

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

Further, the polysilazane represented by the formula (B3) may be, for example, organopolysilazane in which at least one ^R15 is a group other than a hydrogen atom. Perhydropolysilazane and organopolysilazane may be appropriately selected depending on the intended use, and may be mixed and used.

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

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

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

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

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

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

Further, when polysilazane contains a structure represented by a plurality of formulas (B4) in the molecule, a bond of the structure represented by the formula (B4) is a bond of a structure represented by another formula (B4). It may be directly connected to the hand.

It is bonded to any of the polysilazane bond represented by the formula (B3), the polysilazane constituent unit bond represented by the formula (B3), and the structural bond represented by the other formula (B4). ^R14 is bonded to the bond of no N atom.

It is bonded to any of the polysilazane bond represented by the formula (B3), the polysilazane constituent unit bond represented by the formula (B3), and the structural bond represented by the other formula (B4). ^R15 is bonded to the bond of no Si atom.

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 enhancing the effect of suppressing aggregation, the silicon compound layer preferably contains organopolysilazane having a structure represented by the formula (B4).

As an organopolysilazane having a structure represented by the formula (B4), at least one bond is bonded to R ¹⁴ or R ¹⁵ , and at least one of the R ¹⁴ and R ¹⁵ is an alkyl having 1 to 20 carbon atoms. A group, an alkenyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an organopolysilazane which is an alkylsilyl group having 1 to 20 carbon atoms. May be.

Among them, it is preferable that the structure is represented by the formula (B4), at least one bond is bonded to R ¹⁴ or R ¹⁵ , and at least one of the R ¹⁴ and R ¹⁵ is polysilazane, which is a methyl group. ..

The general polysilazane has, for example, a structure in which a linear structure and a ring structure such as a 6-membered ring or an 8-membered ring exist, that is, a structure represented by the above formula (B3) and the above formula (B4). .. The molecular weight of general polysilazane is about 600 to 2000 (in terms of polystyrene) in terms of number average molecular weight (Mn), and may be a liquid or solid substance depending on the molecular weight.

As the polysilazane, a commercially available product may be used, and the commercially available products include NN120-10, NN120-20, NAX120-20, NN110, NAX120, NAX110, NL120A, NL110A, NL150A, NP110, NP140 (AZ Electronic Materials Co., Ltd.). AZNN-120-20, Durazane (registered trademark) 1500 Slow Cure, Durazane 1500 Rapid Cure, Durazane 1800, 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, and more preferably Durazane1500 SlowCure.

The condensate of cilazan includes a condensate of disilazan represented by the formula (B1), a condensate of low molecular weight cilazan represented by the formula (B2), and a condensate of polysilazane represented by the formula (B3). , It is preferable that it is a condensate of polysilazane having a structure represented by the above formula (B4) in the molecule.

Regarding the condensate of low molecular weight silazane represented by the formula (B2), the silicon atom which is not bonded to the nitrogen atom with respect to all the silicon atoms contained in the condensate of low molecular weight silazane represented by the formula (B2). The ratio is preferably 0.1 to 100%. Further, the ratio of the silicon atom not bonded to the nitrogen atom is more preferably 10 to 98%, further preferably 30 to 95%.

The "ratio of silicon atoms not bonded to nitrogen atoms" is defined as ((Si (mol))-(N (mol) in Si—N bond)) / Si (mol) using the measured values described later. ) × 100. Considering the condensation reaction, "the ratio of silicon atoms not bonded to the nitrogen atom" means "the ratio of silicon atoms contained in the siloxane bond generated in the condensation treatment".

Regarding the polysilazane condensate represented by the formula (B3), the ratio of silicon atoms not bonded to the nitrogen atom to all the silicon atoms contained in the polysilazane condensate represented by the formula (B3) is 0. It is preferably 1 to 100%. Further, the ratio of the silicon atom not bonded to the nitrogen atom is more preferably 10 to 98%, further preferably 30 to 95%.

Regarding the condensate of polysilazane having the structure represented by the formula (B4), silicon not bonded to the nitrogen atom for all the silicon atoms contained in the condensate of polysilazane having the structure represented by the formula (B4). The proportion of atoms is preferably 0.1 to 99%. Further, the ratio of the silicon atom not bonded to the nitrogen atom 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).

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

<Hydrolyzable silane compound>
The hydrolyzable silane compound is preferably a silane compound having an amino group, an alkoxy group or an alkylthio group. Examples of the hydrolyzable silane compound include 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, dodecyltrimethoxysilane, trimethoxyphenylsilane, 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane, and trimethoxy. Examples thereof include (1H, 1H, 2H, 2H-nonafluorohexyl) silane, 3-mercaptopropyltrimethoxysilane, and 3-mercaptopropyltriethoxysilane.

Among them, from the viewpoint of durability of luminescent composite particles, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, trimethoxyphenylsilane, trimethoxyphenylsilane, trimethoxy (1H, 1H, 2H, 2H-nona) Fluorohexyl) silane is more preferred.

<Condensate of hydrolyzable silane compound>
The condensate of the hydrolyzable silicon compound may be any compound obtained 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 particle is not particularly limited, such as a spherical shape, a distorted spherical shape, a go stone shape, or a rugby ball shape. The average particle size of the luminescent composite particles is 1 to 100 nm, preferably 5 to 50 nm, more preferably 10 to 30 nm, still more preferably 15 to 30 nm. When the average particle size of the luminescent composite particles is 100 nm or less, the luminescent composite particles containing coarse perovskite compound particles and aggregated perobskite compound particles are removed, and the luminescent composite particles containing fine perovskite compound particles are removed. Particles are selectively obtained. Coarse perovskite compound particles and aggregated perovskite compound particles are considered to be inferior in light resistance, and by selecting fine perovskite compound particles, the light resistance of the luminescent composite particles is improved.

The average particle size of the luminescent composite particles can be measured by, for example, a dynamic light scattering method (DLS: Dynamic Light Scattering) in which the particles are dispersed in a dispersion liquid to form a dispersion liquid composition. Examples of the measuring method in DLS include a method of measuring the dispersion liquid composition in a dedicated container (glass cell).

The average particle size of the luminescent composite particles is adjusted by using a known classification method such as filtering the dispersion containing the synthesized luminescent composite particles using a filter having an appropriate pore size. be able to.

<Amount of silicon compound layer>
From the viewpoint of sufficiently improving the quantum yield in the luminescent composite particles, the mass of the silicon compound layer is preferably 1.1 parts by mass or more, more preferably 1.5 parts by mass with respect to the mass of the perovskite compound. The above is more preferably 1.8 parts by mass or more. The mass of the silicon compound layer is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, and further preferably 20 parts by mass or less with respect to the mass of the perovskite compound.

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

2. 2. Luminescent Composite Particle Composition Containing a Perovskite Compound FIG. 2 is a cross-sectional view schematically showing the structure of a composition containing the luminescent composite particles of the present invention. The luminescent composite particle composition 200 has a luminescent composite particle 100 and a dispersion medium material 30. The luminescent composite particles 100 are dispersed in the dispersion medium material 30.

In the following description, since the functions of dispersing the luminescent composite particles are common, the dispersion medium (3), the polymerizable compound (4), and the polymer (5) described below are collectively referred to as “dispersion medium”. Sometimes referred to as "material". The dispersion medium material is a support medium in which the perovskite compound particles are difficult to dissolve, and it is preferable that the perovskite compound particles do not dissolve. Further, 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 particles are suspended in a dispersion medium material. When the particles are dispersed in the liquid dispersion medium material, some of the particles may be settled.

(Dispersion medium (3))
The dispersion medium (3) is an inert compound that exhibits a liquid state at 25 ° C. and 1 atm and can coexist with the perovskite compound particles. In the present specification, the dispersion medium (3) does not include the polymerizable compound (4) described later.

Examples of the dispersion medium (3) include the following (a) to (k).
(A) Ester (b) Ketone (c) Ether (d) Alcohol (e) Glycol ether (f) Organic solvent having an amide group (g) Organic solvent having a nitrile group (h) Organic solvent having a carbonate group (i) ) Hydrocarbonized hydrocarbon (j) Hydrocarbon (k) Dimethylsulfoxide (l) Ion liquid

Examples of the (a) ester include methylformate, ethylformate, propylformate, pentylformate, methyl acetate, ethyl acetate, pentyl acetate and the like.

Examples of the (b) ketone include γ-butyrolactone, N-methyl-2-pyrrolidone, acetone, diisobutylketone, cyclopentanone, cyclohexanone, and methylcyclohexanone.

(C) Examples of the ether include diethyl ether, methyl-tert-butyl ether, diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, 4-methyldioxolane, tetrahydrofuran, methyltetrahydrofuran, anisole and phenetol. And so on.

(D) Alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tert-butanol, 1-pentanol, 2-methyl-2-butanol, methoxypropanol and diacetone alcohol. , Cyclohexanol, 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol and the like.

Examples of the (e) glycol ether include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, and triethylene glycol dimethyl ether.

(F) Examples of the organic solvent having an amide group include N, N-dimethylformamide, acetamide, N, N-dimethylacetamide and the like.

(G) Examples of the organic solvent having a nitrile group include acetonitrile, isobutyronitrile, propionitrile, methoxynitrile and the like.

(H) Examples of the organic solvent having a carbonate group include ethylene carbonate and propylene carbonate.

(I) Examples of the halogenated hydrocarbon include methylene chloride and chloroform.

Examples of the (j) hydrocarbon include n-pentane, cyclohexane, n-hexane, 1-octadecene, benzene, toluene, xylene and the like.

(L) Examples of the ionic liquid include ammonium-based, phosphonium-based, and sulfonium-based liquids as cationic liquids, and AlCl ^4- , NO ^2- , NO ^3- , and I as anionic liquids. ^- , 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- ^, etc. can be mentioned.

Among these solvents, (a) ester, (b) ketone, (c) ether, (g) organic solvent having a nitrile group, (h) organic solvent having a carbonate group, (i) halogenated hydrocarbon and (i) j) Hydrocarbons are preferable because they have low polarity and are considered to be difficult to dissolve luminescent composite particles.

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

As the dispersion medium (3), only one type 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. Examples of the polymerizable compound include a monomer that is in a liquid state at 25 ° C. and 1 atm.

For example, when produced at room temperature and under normal pressure, the polymerizable compound is not particularly limited. Examples of the polymerizable compound include known polymerizable compounds such as styrene, acrylic acid ester, methacrylic acid ester, and acrylonitrile. Among them, as the polymerizable compound, one or both of acrylic acid ester and methacrylic acid ester, which are monomers of the acrylic resin, is preferable.

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

The ratio of the total amount of the acrylic acid ester and the methacrylic acid ester to the total mass of the polymerizable compound (4) may be 10 mol% or more. The same 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 low solubility of the luminescent composite particles at the temperature at which the luminescent composite particle composition is produced.

For example, when the polymer is produced at room temperature and under normal pressure, the polymer is not particularly limited, and examples thereof include known polymers such as polystyrene, acrylic resin, and epoxy resin. Among them, acrylic resin is preferable as the polymer. The acrylic resin contains one or both of a structural unit derived from an acrylic acid ester and a structural unit derived from a methacrylic acid ester. These resins may be prepared, for example, by polymerizing the corresponding monomer, the polymerizable compound (4), in the luminescent composite particle composition.

The ratio of the total amount of the structural unit derived from the acrylic acid ester and the structural unit derived from the methacrylic acid ester to all the structural units contained in the polymer (5) may be 10 mol% or more. The same 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 1200,000, more preferably 1,000 to 800,000, and even more preferably 5,000 to 150,000.

As used herein, the term "weight average molecular weight" means a polystyrene-equivalent value measured by a gel permeation chromatography (GPC) method.

The polymer (5) may have only one type, 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). Further, it may have other components other than the above (1) to (6). For example, it may further contain some impurities, a compound having an amorphous structure composed of elements constituting the perovskite compound (1), and a polymerization initiator.

When the luminescent composite particle composition contains 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) comprises 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. Use as a forming material.

Among them, it is preferable to use at least one selected from the group consisting of amines and carboxylic acids as the forming material.

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

(Ammonium ion, primary to quaternary ammonium cation, ammonium salt)
Ammonium ions, which are surface modifiers (6), and primary to quaternary ammonium cations are represented by the following formula (A1). The ammonium salt which is the surface modifier (6) is a salt containing an ion represented by the following formula (A1).

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. Examples of the saturated hydrocarbon group include an alkyl group and a cycloalkyl group.

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

The unsaturated hydrocarbon groups ^R1 to ^R4 may be linear or branched.

The number of carbon atoms of the unsaturated hydrocarbon group 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 hydrogen atoms, alkyl groups, or unsaturated hydrocarbon groups.
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 in R ⁶ to R ⁹ .

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

As the alkenyl group of R ¹ to R ⁴ , in the linear or branched alkyl group exemplified in R ⁶ to R ⁹ , a single bond (CC) between any one carbon atom is two. Examples thereof include those substituted with a double bond (C = C), and the position of the double bond is not limited.

Preferred alkenyl groups of ^R1 to ^R4 are, for example, an ethenyl group, a propenyl group, a 3-butenyl group, a 2-butenyl group, a 2-pentenyl group, a 2-hexenyl group, a 2-nonenyl group and a 2-dodecenyl group. Groups include 9-octadecenyl groups.

When the ammonium cation represented by the formula (A1) forms a salt, the counter anion is not particularly limited. As the counter anion, a halide ion, a carboxylate ion, or the like is preferable. Examples of the halide ion include bromide ion, chloride ion, iodide ion, and fluoride ion.

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

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

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

The amine as the surface modifier (6) may be any of primary and tertiary amines, but primary amines and secondary amines are preferable, and primary amines are more preferable.

As the amine which is the surface modifier (6), oleylamine is preferable.

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

Examples of the carboxylic acid as the surface modifier (6) include carboxylic acids in which a proton (H ⁺ ) is bound to the carboxylate anion represented by the above (A2).

In the ion represented by the formula (A2), R ⁵ represents a monovalent hydrocarbon group. The hydrocarbon group represented by ^R5 may be a saturated hydrocarbon group or an unsaturated hydrocarbon group.
Examples of the saturated hydrocarbon group include an alkyl group and a cycloalkyl group.

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

The number of carbon atoms of the alkyl group represented by R5 is usually 1 to 20, preferably ⁵ to 20, and more preferably 8 to 20.

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

The unsaturated hydrocarbon group represented by ^R5 may be linear or branched.

The number of carbon atoms of the unsaturated hydrocarbon group represented by R5 is usually 2 to 20, preferably ⁵ to 20, and more preferably 8 to 20.

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

Specific examples of the alkyl group of R ⁵ include the alkyl groups exemplified in R ⁶ to R ⁹ .
Specific examples of the cycloalkyl group of R ⁵ include the cycloalkyl groups exemplified in R ⁶ to R ⁹ .

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

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

When the carbochelate anion forms a salt, the counter cation is not particularly limited, but alkali metal cations, alkaline earth metal cations, ammonium cations and the like are preferable examples.

Oleic acid is preferable as the carboxylic acid that is the surface modifier (6).

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

Of the ammonium salts and ammonium ions, oleylamine salts and oleylammonium ions are more preferable.

Among the carboxylate salts and carboxylate ions, oleate and oleate cations are more preferable.

In the luminescent composite particles, only one kind of the above-mentioned surface modifier (6) may be contained, or two or more kinds thereof may be used in combination.

<Contents of each component in the luminescent composite particle composition>
In the luminescent composite particle composition, the content ratio of the luminescent composite particles 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, further preferably 10% by mass or less, and 3% by mass or less. Is particularly preferred.

Further, the content ratio is preferably 0.0002% by mass or more, more preferably 0.002% by mass or more, and more preferably 0.01% by mass or more from the viewpoint of obtaining a good quantum yield. Is even more preferable.

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

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

In the luminescent 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 range, the luminescent composite particles are less likely to aggregate and the luminescence is well exhibited. Is preferable.

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

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

Further, the content ratio is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and 0.1% by mass, from the viewpoint of improving the durability of the luminescent composite particles. The above is more preferable.

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

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

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

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.

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

Further, the content ratio is preferably 0.1% by mass or more, more preferably 1% by mass or more, still more preferably 10% by mass or more, and more preferably 50, from the viewpoint of improving the light resistance. It is more preferably mass% or more, more preferably 80% by mass or more, and most preferably 90% by mass or more.

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

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 with respect to the total mass of the luminescent composite particle composition is preferably 1 to 99% by mass, more preferably 10 to 99% by mass, and preferably 20 to 99% by mass. More preferably, it is particularly preferably 50 to 99% by mass, and most preferably 90 to 99% by mass.

Further, 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 medium material may be 90% by mass or more with respect to the total mass of the luminescent composite particle composition. , 95% by mass or more, 99% by mass or more, or 100% by mass.

In the luminescent composite particle composition, the content ratio of the surface modifier (6) 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 further preferably 0.1% by mass or less.

Further, the content ratio is preferably 0.0001% by mass or more, more preferably 0.001% by mass or more, and more preferably 0.01% by mass or more from the viewpoint of improving the light durability. Is even more preferable.

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

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

A luminescent composite particle composition in which the content ratio of the surface modifier (6) to the total mass of the luminescent composite particle composition is within the above range is preferable because it is excellent in light durability.

The total content of the luminescent composite particles, the compound having an amorphous structure composed of some impurities, the elements constituting the perovskite compound (1), and the polymerization initiator is 10% by mass with respect to the total mass of the luminescent composite particle composition. % Or less, more preferably 5% by mass or less, and even more preferably 1% by mass or less.

3. 3. Method for producing luminescent composite particles The method for producing perovskite compound particles is produced by the method described below with reference to known documents (Nano Lett. 2015, 15, 3692-3696, ACSNano, 2015, 9, 4533-4542). be able to.

(First manufacturing method)
The method for producing a perovskite compound includes a step of dissolving a component B, a component X, and a component A constituting the perovskite compound in the above-mentioned dispersion medium (3) at a high temperature to obtain a solution, and a step of cooling the solution. The method can be mentioned.

Hereinafter, the first manufacturing method will be specifically described.

First, the compound containing the B component and the X component and the compound containing the A component are dissolved in a high-temperature dispersion medium (3) to obtain a solution. The "compound containing the A component" may contain the X component.
In this step, each compound may be added to a high-temperature dispersion medium (3) and dissolved to obtain a solution.
Further, in this step, a solution may 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.

As the dispersion medium (3), a solvent capable of dissolving the compound containing the B component and the X component, which are raw materials, and the compound containing the A component is preferable.

The "high temperature" may be a solvent having 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 the temperature rise is preferably, for example, 20 to 150 ° C, preferably 120 to 140 ° C. Is more preferable.

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

The resulting solution is then cooled.
The cooling temperature is preferably −20 to 50 ° C., more preferably −10 to 30 ° C.
The cooling rate is preferably 0.1 to 1500 ° C./min, more preferably 10 to 150 ° C./min.

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

The perovskite compound can be recovered by performing solid-liquid separation on the obtained dispersion containing the perovskite compound. Examples of the solid-liquid separation method include filtration and concentration by evaporation of a solvent. By performing solid-liquid separation, only the perovskite compound can be recovered.

It should be noted that the above-mentioned production method preferably includes the step of adding the above-mentioned surface modifier (6) because the particles of the obtained perovskite compound are stably and easily dispersed in the dispersion liquid.

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

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

(Second manufacturing method)
As a method for producing a perovskite compound, a step of obtaining a first solution containing components A and B constituting the perovskite compound, a step of obtaining a second solution containing the component X constituting the perovskite compound, and a first solution and a first solution are used. Examples thereof include a manufacturing method including a step of mixing two solutions to obtain a mixed solution and a step of cooling the obtained mixed solution.

Hereinafter, the second manufacturing method will be specifically described.

First, the compound containing the component A and the compound containing the component B are dissolved in a high-temperature second solvent to obtain a first solution.
In this step, each compound may be added to a high-temperature dispersion medium (3) and dissolved to obtain a first solution.
Further, 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.

As the dispersion medium (3), a solvent capable of dissolving the compound containing the A component and the compound containing the B component is preferable.

The "high temperature" may be any temperature as long as the compound containing the A component and the compound containing the B component are melted. 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 raising the temperature is preferably, for example, 80 to 150 ° C, preferably 120 to 140 ° C. It is more preferable to have.

Further, the compound containing the X component is dissolved in the above-mentioned dispersion medium (3) to obtain a second solution. A 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).

Examples of the dispersion medium (3) include a solvent capable of dissolving a compound containing an X component.

Next, the obtained first solution and the second solution are mixed to obtain a mixed solution. When mixing the first solution and the second solution, one may be dropped onto the other. Further, it is advisable to mix the first solution and the second solution with stirring.

The resulting mixture is then cooled.
The cooling temperature is preferably −20 to 50 ° C., more preferably −10 to 30 ° C.
The cooling rate is preferably 0.1 to 1500 ° C./min, more preferably 10 to 150 ° C./min.

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

With respect to the obtained dispersion containing the perovskite compound, the perovskite compound can be recovered by performing solid-liquid separation. Examples of the solid-liquid separation method include the method shown in the first production method.

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

Further, it is preferable that the above-mentioned manufacturing method includes a step of removing coarse particles by a method such as centrifugation and filtration shown in the first manufacturing method after the step of cooling.

<Manufacturing of luminescent composite particles>
In the luminescent composite particles, for example, the perovskite compound particles and the hydrolyzable silicon compound (2) are brought into contact with each other, and the hydrolyzable silicon compound (2) is condensed as necessary, and the silicon compound layer is formed on the surface of the perovskite compound particles. Is manufactured by forming. The contact between the perovskite compound particles and the hydrolyzable silicon compound (2) may be carried out in the presence of the dispersion medium (3). In such a case, the dispersion medium (3) is removed after forming the particles.

When removing the dispersion medium (3), the dispersion liquid of the particles may be allowed to stand at room temperature and air-dried, may be vacuum-dried using a vacuum dryer, or may be heat-dried by heating. good. 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. The dispersion liquid of the particles containing the dispersion medium (3) may be used as it is or by adjusting the concentration as it is as a luminescent composite particle composition.

(Condensation treatment of hydrolyzable silicon compound (2))
The condensation treatment of the hydrolyzable silicon compound (2) can be carried out by using a known method such as a method of reacting the silazane and the hydrolyzable silicon compound with water vapor. In the following description, the treatment of reacting the silazane and the hydrolyzable silicon compound with water vapor may be referred to as "humidification treatment". Humidification treatment is preferable from the viewpoint of forming a stronger protected region in the vicinity of the perovskite compound particles.

When the humidification treatment is performed, for example, the luminescent composite particle composition may be allowed to stand for a certain period of time under the temperature and humidity conditions described later, or may be stirred for a certain period of time under the same conditions.

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

The humidity in the humidification treatment may be any humidity as long as sufficient water is supplied 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 even more preferably 60% to 90%.

The time required for the humidification treatment may be a time during which the condensation proceeds sufficiently. 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 further preferably 2 hours or more and 3 days or less.

Water may be supplied in the humidification treatment by circulating a gas containing water vapor in the reaction vessel, or by stirring in an atmosphere containing water vapor to supply water from the interface.

When a gas containing water vapor is circulated in the reaction vessel, the flow rate of the gas containing water vapor is preferably 0.01 L / min or more and 100 L / min or less, preferably 0, in order to improve the durability of the obtained luminescent composite particle composition. .1 L / min or more and 10 L / min or less is more preferable, and 0.15 L / min or more and 5 L / min or less is further preferable. Examples of the gas containing water vapor include nitrogen containing a saturated amount of water vapor.

4. Method for Producing a Luminous Composite Particle Composition A luminescent composite particle composition, that is, a mixture of the particles and a dispersion medium material can be produced, for example, by dispersing the particles in a dispersion medium material.

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

The luminescent composite particle composition can also be obtained by polymerizing the polymerizable compound (4) to obtain a part thereof as the polymer (5). In this case, it is preferable that the total of the particles and the polymer (5) is 90% by mass or more of the total amount of the luminescent composite particle composition.

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

For example, in the case of radical polymerization, the polymerization reaction can be promoted by adding a radical polymerization initiator to the mixture of the particles and the polymerizable compound (4) and generating radicals.

The radical polymerization initiator is not particularly limited, and examples thereof include a photoradical polymerization initiator.

Examples of the photoradical polymerization initiator include bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide and the like.

When the surface modifier (6) is used, the surface modifier (6) can 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 absorption rate and quantum yield of luminescent composite particles are determined by an absolute PL quantum yield measuring device (for example, "C9920-02" manufactured by Hamamatsu Photonics Co., Ltd. (Commodity). It can be measured using the name)).
Further, the luminance maintenance rate can be calculated from the following equation using these values. In the present invention, the measurement is carried out under the conditions of an excitation light of 450 nm, 25 ° C. and 1 atm.

Brightness retention rate (%) = [(Quantum yield of luminescent composite particle composition after light resistance test) ÷ (Quantum yield of luminescent composite particle composition before light resistance test)] × [(Light emission after light resistance test) Absorption rate of sex composite particle composition) ÷ (absorption rate of luminescent composite particle composition before light resistance test)] × 100

The absorption rate of the excitation light of the luminescent composite particle is preferably 0.1 or more and less than 1, more preferably 0.2 or more and less than 0.9, and further 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 even more preferably 0.3 to 0.95.

The brightness retention rate of the luminescent composite particles is preferably 0.3 to 1.0, more preferably 0.5 to 1.0, and even more preferably 0.7 to 1.0. When the brightness retention rate is within these ranges, a luminescent particle material having high light resistance can be obtained.

6. Film The film of the present invention contains the luminescent composite particles of the present invention. For example, the film according to the present invention contains luminescent composite particles and a polymer (5). Typically, the total of the particles and the polymer (5) occupies 90% by mass or more of the whole film.

The film shape is not particularly limited, and can be any shape such as a sheet shape or a bar shape. As used herein, the term "bar-shaped" means, for example, a planar visual band-shaped shape extending in one direction. Examples of the plan-view band-shaped shape include a plate-shaped shape having different lengths on each side.

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 is, for example, coated with a liquid luminescent composite particle composition containing a dispersion medium (3) and a polymerizable compound (4) to obtain a coating film, and then the polymerizable compound contained in the coating film ( It can be obtained by polymerizing 4). The method for coating the liquid luminescent composite particle composition on the substrate is not particularly limited, and the gravure coating method, bar coating method, printing method, spray method, spin coating method, dip method, die coating method, etc. are used. , Can be applied using known coating and coating methods.

7. Laminated Structure The laminated structure of the present invention has a plurality of layers, and at least one layer is the above-mentioned film.
Among the plurality of layers of the laminated structure, examples of layers other than the above-mentioned film include arbitrary layers such as a base material, a barrier layer, and a light scattering layer. The shape of the laminated film is not particularly limited, and may be any shape such as a sheet shape or a bar shape. The base material is preferably one having light transmission because it is easy to take out the light emitted by the perovskite compound (1). As the material for forming the base material, for example, a polymer such as polyethylene terephthalate or a known material such as glass can be used.

The laminated structure can be manufactured, for example, by laminating the obtained film on a base material. In the process of laminating the film on the base material, the films are bonded to each other using an adhesive. The adhesive is not particularly limited as long as it does not dissolve the luminescent composite particles, and the adhesive can be bonded using a known adhesive.

8. Light emitting device The light emitting device of the present invention can be obtained by combining the laminated structure and a light source. The light emitting device is a device that emits light from a light source by irradiating the laminated structure installed in the subsequent stage to emit light and extracts light. Among the plurality of layers of the laminated structure in the light emitting device, the layers other than the above-mentioned film, base material, barrier layer, and light scattering layer include a light reflecting member, a brightness enhancing portion, a prism sheet, a light guide plate, and between elements. Any layer such as a medium material layer of the above can be mentioned. As a specific example of the light emitting device, for example, it is a light emitting device in which a prism sheet, a light guide plate, the laminated structure, and a light source are laminated in this order.

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

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

10. The scintillator The luminescent composite particle or the luminescent composite particle composition can be used as a scintillator in an X-ray image photographing apparatus or a brightness improving film. The form of the scintillator is not particularly limited, and can be used in any form such as a single crystal or a sheet.

When used in the form of a sheet, the scintillator can be manufactured by applying a liquid luminescent composite particle composition containing luminescent composite particles onto a substrate and drying it. The base material used is not particularly limited, and for example, aluminum metal, PET film, moth-eye film, or the like can be used. The scintillator may be used in combination with other commercially available scintillators.

FIG. 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 has a scintillator panel 2, an output board 3, and a power supply unit 12.

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

The output board 3 has a photoelectric conversion layer 8 and an output layer 9 on the board 11. The photoelectric conversion layer 8 is generally formed by forming a pixel having a photo sensor and a TFT (not shown) in a two-dimensional manner. The diaphragm layer 7 may be provided on the photoelectric conversion layer 8. It is preferable that the light emitting surface of the scintillator panel 2 and the photoelectric conversion layer 8 of the output substrate 3 are adhered or brought into close contact with each other via the diaphragm layer 7.

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

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>
The following items were measured and evaluated according to the following methods for the luminescent composite particles obtained in the following Examples and Comparative Examples.

(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) was obtained from the obtained electron microscope image. I asked. In the calculation, the distance between the parallel lines sandwiching the particles between two parallel lines was taken as the ferret diameter, and the arithmetic mean of the ferret diameters of 50 particles was used. The sample was obtained by collecting perovskite compound particles from the luminescent composite particle composition on a grid with a support film. The measurement conditions were an acceleration voltage of 200 kV.

(Particle size of luminescent composite particles)
The average particle size of the luminescent composite particles was measured using a particle size analyzer (“Zetasizer Nano ZS” (trade name) manufactured by Malvern). The measurement method used was a dynamic light scattering method. The obtained luminescent composite particles were used as a number average distribution, and the average particle size and standard deviation σ were determined. The measurement sample was measured by dropping the dispersion liquid into a predetermined container (glass).

(Quantum yield, absorption rate)
The quantum yield and absorption rate of the luminescent composite particle composition obtained in Examples 1, 2, 3 and Comparative Example 1 are measured by an absolute PL quantum yield measuring device (“C9920-02” manufactured by Hamamatsu Photonics Co., Ltd. (Commodity). Name)) was used for measurement. The measurement was performed before and after the following light irradiation, and the measurement conditions were an excitation light of 450 nm, 25 ° C., and 1 atm.

(Evaluation of light resistance)
100 μL of the luminescent composite particle composition obtained in Examples 1, 2 and 3 and Comparative Example 1 was applied onto a glass substrate having a size of 1 cm × 1 cm and air-dried to obtain a film. While heating the obtained film to 50 ° C., light having a peak wavelength of 450 nm and an illuminance of 100 mW / cm ² was irradiated from the LED light source for 48 hours.

From the quantum yield and absorption rate of the luminescent composite particle composition before and after light irradiation, the brightness maintenance rate was determined based on the following formula. It can be evaluated that the higher the value of the brightness maintenance rate, the higher the light resistance. The evaluation was performed on the ones 48 hours after the light irradiation.

[Example 1]
(Manufacturing of perovskite compound particles)
After mixing 25 mL of oleylamine and 200 mL of ethanol, the mixture was stirred while cooling with ice, 17.12 mL of an aqueous hydrogen bromide solution (48%) was added, and then dried under reduced pressure to obtain a precipitate. The precipitate was washed with diethyl ether and then dried under reduced pressure to obtain oleylammonium bromide.

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

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

100 mL of toluene and 100 mL of ethyl acetate were mixed with 200 mL of the above dispersion, filtered and separated into solid and liquid. 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, and further filtered. As a result, perovskite compound particles were isolated.

(Manufacturing of luminescent composite particle composition)
Next, using toluene as a dispersion medium, a 150 mL dispersion was prepared so that the concentration of the perovskite compound particles was 0.34% by mass. To this, organopolysilazane (1500 Slow Cure, Durazane, manufactured by Merck Performance Materials Co., Ltd.) was added in an amount of 2.0 parts by mass with respect to 1 part by mass of the perovskite compound. Then, the condensation treatment with steam was carried out for 4 hours, and it was allowed to stand in a dry nitrogen atmosphere for 0.5 hours. The condensation treatment was carried out under a steam flow rate of 0.4 L / min (supplied with _N2 gas, saturated steam amount at 30 ° C.) and a heating temperature of 90 ° C. The dispersion liquid after the condensation treatment was filtered through a 0.5 μm membrane filter to obtain a luminescent composite particle composition. The obtained luminescent composite particle composition was measured by DLS to estimate the average particle size of the particles. The average particle size was 27.26 nm ± 8.5. The brightness maintenance rate after the light resistance test was 70.1%.

[Example 2]
In the process of producing the luminescent composite particles, the luminescent composite was carried out by the same method as in Example 1 above, except that the dispersion liquid of the perovskite compound particles was set to 150 mL to 30 mL and the gas flow rate during the condensation treatment was set to 0.08 L / min. A particle composition was obtained. The average particle size of the particles was estimated to be 26.54 nm ± 5.4 by the same method. The brightness maintenance rate was 78.0%.

[Example 3]
Trimethoxy (1H, 1H, 2H, 2H-nonafluorohexyl) silane (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 0.25 with respect to 1 part by mass of organopolysilazane after addition of organopolysilazane in the manufacturing process of luminescent composite particles. A luminescent composite particle composition was obtained in the same manner as in Example 2 above, except that a mass portion was further added. When the average particle size of the particles was estimated by the same method, it was 17.59 nm ± 5.2. The brightness maintenance rate was 100%.

[Comparative Example 1]
In the step of producing the luminescent composite particles according to Example 1, a luminescent composite particle composition was obtained by the same method except that the obtained luminescent composite particle composition was not filtered by a membrane filter. The average particle size of the particles was estimated by the same method and was 495.2 nm ± 142.0. The brightness maintenance rate was 24.8%.

The above measurements were performed on the luminescent composite particles of Examples 1 to 3 and Comparative Example 1. The results are shown in Table 1.

From the above results, it was confirmed that the luminescent composite particles containing the perovskite compound having an average particle size of 1 to 100 nm in Examples 1 to 3 are superior in light resistance to the luminescent composite particles of Comparative Example 1. ..

[Reference Example 1]
The luminescent composite particle composition according to Examples 1 to 3 is placed in a glass tube or the like and sealed, and then the blue light emitting diode is placed between the blue light emitting diode as a light source and the light guide plate. Manufacture a backlight that can convert blue light into green light or red light.

[Reference Example 2]
A resin composition can be obtained by forming a sheet of the light-emitting composite particle composition according to Examples 1 to 3, and a film sandwiched between two barrier films and sealed is placed on a light guide plate. By doing so, a backlight capable of converting the blue light emitted from the blue light emitting diode placed on the end surface (side surface) of the light guide plate to the sheet through the light guide plate into green light or red light is manufactured.

[Reference Example 3]
By installing the luminescent composite particle composition according to Examples 1 to 3 in the vicinity of the light emitting portion of the blue light emitting diode, a backlight capable of converting the blue light emitted into green light or red light is manufactured. do.

[Reference example 4]
A wavelength conversion material can be obtained by mixing the luminescent composite particle composition according to Examples 1 to 3 with a resist and then removing the solvent. By arranging the obtained wavelength conversion material between the blue light emitting diode which is the light source and the light guide plate or after the OLED which is the light source, a backlight capable of converting the blue light of the light source into green light or red light can be obtained. To manufacture.

[Reference Example 5]
The light-emitting composite particle composition according to Examples 1 to 3 is formed by mixing conductive particles such as ZnS to form a film, and an n-type transport layer is laminated on one side and the other side is laminated with a p-type transport layer. Get the LED.
By passing an electric current, the holes of the p-type semiconductor and the electrons of the n-type semiconductor can be made to emit light by canceling the charges in the perovskite compound on the bonding surface.

[Reference Example 6]
A dense layer of titanium oxide is laminated on the surface of a fluorine-doped tin oxide (FTO) substrate, a porous aluminum oxide layer is laminated on the dense layer, and the luminescent composite particles according to Examples 1 to 3 are laminated thereto. After laminating the composition and removing the solvent, 2,2', 7,7'-tetrakis- (N, N'-di-p-methoxyphenyllamine) -9,9'-spirobifluorene (Spiro-OMeTAD) A solar cell is manufactured by laminating a hole transport layer such as, and then laminating a silver (Ag) layer on the whole.

[Reference Example 7]
The composition of the present embodiment can be obtained by removing the solvent from the composition containing the luminescent composite particles according to Examples 1 to 3, and installing the composition after the blue light emitting diode. Therefore, a laser diode lighting that emits white light by converting blue light radiated from a blue light emitting diode onto a composition into green light or red light is manufactured.

[Reference Example 8]
The composition of the present embodiment can be obtained by removing the solvent of the composition containing the luminescent composite particles according to Examples 1 to 3 and molding the composition. By using the obtained composition as a part of the photoelectric conversion layer, a photoelectric conversion element (photodetection element) material contained in a detection unit for detecting light is manufactured. The photoelectric conversion element material is a part of a living body such as an image detection unit (image sensor) for a solid-state image sensor such as an X-ray image sensor and a CMOS image sensor, a fingerprint detection unit, a face detection unit, a vein detection unit, and an iris detection unit. It is used in an optical biosensor such as a detection unit that detects a predetermined feature and a pulse oximeter.

[Reference Example 9]
The composition of the present embodiment can be obtained by removing the solvent of the composition containing the luminescent composite particles according to Examples 1 to 3 and molding the composition. The obtained composition can be used as a film for improving the light conversion efficiency of the solar cell. The form of the conversion efficiency improving sheet is not particularly limited, but is used in the form of being applied to a base material. The base material is not particularly limited as long as it is a highly transparent base material. For example, PET film or moth-eye film is desirable. The solar cell using the solar cell conversion efficiency improving sheet is not particularly limited, and the conversion efficiency improving sheet has a conversion function from a wavelength region in which the sensitivity of the solar cell is low to a wavelength region in which the sensitivity is high.

[Reference Example 10]
The composition of the present embodiment can be obtained by removing the solvent of the composition containing the luminescent composite particles according to Examples 1 to 3 and molding the composition. The obtained composition can be used as a light source for single photon generation such as quantum computer, quantum teleportation and quantum cryptography communication.

10 ... Perovskite compound particles,
20 ... Silicon compound layer,
30 ... Dispersion medium material,
100 ... Luminous composite particles,
200 ... Luminous composite particle composition.

Claims

Perovskite-type crystal structure containing A, B, and X as constituents
[In the perovskite-type crystal structure, A is a component located at each vertex of a hexahedron centered on B, and is a monovalent cation.
B is a component located at the center of a hexahedron in which A is arranged at the apex and an octahedron in which X is arranged at the apex, and is a metal ion.
X is a component located at each vertex of the octahedron centered on B, and is at least one kind of anion selected from the group consisting of a halide ion and a thiocyanate ion. ]
A luminescent composite particle having a perovskite compound particle having luminescence and a silicon compound layer formed on at least a part of the surface of the perovskite compound particle, and having an average particle size of 1 to 100 nm. Luminescent composite particles with.
The luminescent composite particle according to claim 1, wherein the silicon compound layer is a layer composed of at least one 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 perovskite compound particle having luminescence has a primary particle diameter of 1 to 80 nm.
A luminescent composite particle composition containing 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 containing the luminescent composite particles according to any one of claims 1 to 3.
A laminated structure including the film according to claim 5.
A light emitting device including the laminated structure according to claim 6.
A display comprising the laminated structure according to claim 6.
A scintillator containing the luminescent composite particles according to any one of claims 1 to 3.