WO2018128144A1

WO2018128144A1 - Composition containing fluorescent particles, wavelength conversion layer, and production method for wavelength conversion layer

Info

Publication number: WO2018128144A1
Application number: PCT/JP2017/046914
Authority: WO
Inventors: 慶友保田; 英行神井
Original assignee: Jsr株式会社
Priority date: 2017-01-06
Filing date: 2017-12-27
Publication date: 2018-07-12
Also published as: KR20190098130A; JPWO2018128144A1; TW201835297A

Abstract

The present invention relates to a composition containing fluorescent particles, a wavelength conversion layer and a production method for a wavelength conversion layer. The composition containing fluorescent particles either: includes fluorescent particles (A), hollow particles (B) and an organic solvent (C), wherein the fluorescent particles (A) include In; or includes fluorescent particles (A), hollow particles (B) and an organic solvent (C), wherein the hollow particles (B) are hollow organic particles.

Description

Phosphor particle-containing composition, wavelength conversion layer, and method for producing wavelength conversion layer

The present invention relates to a phosphor particle-containing composition, a wavelength conversion layer, and a method for producing the wavelength conversion layer.

For display devices using an electroluminescence (EL) element or the like, phosphor particles are used. For example, a wavelength conversion layer containing phosphor particles is used.
As the phosphor particles, in recent years, quantum dots (hereinafter also referred to as “QD”) have been attracting attention due to the feature that the emission wavelength can be freely controlled by controlling the size, and to the display device of the QD. Studies are underway for applications such as, and for applications that utilize the degree of freedom of the emission wavelength.

In recent years, display devices have been required to be light and thin, and the light emitting layer (wavelength conversion layer) having phosphor particles that constitute the display device is also required to be thin. However, when such a light emitting layer or the like is thinned, the amount of phosphor in the layer is reduced accordingly, making it difficult to secure a desired light emission amount.

For such a problem, for example, Patent Document 1 discloses a reflective material selected from the group consisting of QD, barium sulfate, titanium dioxide, polytetrafluoroethylene, aluminum silicate, and yttrium aluminum garnet (YAG). And a composition comprising:

In addition, it is known that the characteristics of the wavelength conversion layer are affected by moisture. As a method for reducing such influence, for example, the wavelength conversion layer is sealed with a sealing member, or the wavelength conversion layer is used. A method of providing a barrier layer on at least one of these is disclosed (Patent Documents 2 and 3).

Special table 2015-522668 gazette JP 2012-4567 A International Publication No. 2016/75950

However, when a conventional composition such as the composition described in Patent Document 1 is used, the luminous efficiency in the resulting layer is not sufficient.
One embodiment of the present invention provides a composition capable of easily forming a film or a molded body having high luminous efficiency.

Further, in the methods described in Patent Documents 2 and 3, it is necessary to provide layers other than the wavelength conversion layer such as a sealing member and a barrier layer, and there is a demand for recent devices that are required to be light and thin. There was room for improvement in that it was not satisfactory and the manufacturing cost increased.
One embodiment of the present invention provides a wavelength conversion layer having high luminous efficiency and low moisture absorption.

As a result of intensive studies to solve the above problems, the present inventor has found that the above problems can be solved according to the following configuration example, and has completed the present invention.

[1] including phosphor particles (A), hollow particles (B) and an organic solvent (C),
The phosphor particles (A) contain In,
Phosphor particle-containing composition.

[2] including phosphor particles (A), hollow particles (B) and an organic solvent (C),
The hollow particles (B) are organic hollow particles.
Phosphor particle-containing composition.

[3] The composition according to [1] or [2], wherein the hollow particles (B) have a toluene insoluble content of 90 to 100% by mass.

[4] The composition according to any one of [1] to [3], comprising a bifunctional or higher functional (meth) acrylic acid ester.
[5] The composition according to any one of [1] to [4], comprising a binder resin.

[6] The composition according to any one of [1] to [5], wherein an average film thickness of the shell of the hollow particles (B) is 0.005 to 0.1 μm.

[7] The phosphor particles (A) include an InP / ZnS compound, an InP / ZnSe compound, an InP / ZnSe / ZnS compound, an InP / (ZnS / ZnSe) solid solution compound, an InP / ZnSeS compound, a CuInS ₂ / ZnS compound, The composition according to any one of [1] to [6], comprising at least one quantum dot selected from the group consisting of an AgInS ₂ compound, a (ZnS / AgInS ₂ ) solid solution / ZnS compound, and a Zn-doped AgInS ₂ compound .

[8] The organic solvent (C) is 1,2-propylene glycol-1-methyl ether-2-acetate, 1,3-butanediol-1-acetate-3-methyl ether, 3-methoxybutanol, 1, 2-propylene glycol-1-methyl ether, 1,2-propylene glycol-1-ethyl ether, diethylene glycol monopropyl ether, di (1,3-propylene glycol) -1-monomethyl ether, cyclohexanone, 3-ethoxybutanol, 3 Selected from the group consisting of -hydroxypropionic acid-1-ethyl ester-3-ethyl ether, 3-hydroxypropionic acid-1-methyl ether-1-methyl ester, diethylene glycol dimethyl ether and diethylene glycol methyl ethyl ether Even without a one composition according to any one of [1] to [7].

[9] A wavelength conversion layer formed using the phosphor particle-containing composition according to any one of [1] to [8].

[10] The wavelength conversion layer according to [9], wherein the moisture absorption is 0.01 to 3%.

[11] A wavelength conversion layer containing phosphor particles (A) and a light diffusing material (B ′) and having a moisture absorption of 0.01 to 3%.

[12] In the bending resistance test by the cylindrical mandrel method according to JIS-K5600-5-1: 1999, the relationship between the diameter (mm) of the mandrel where the crack occurs and the thickness (μm) of the wavelength conversion layer is as follows. The wavelength conversion layer according to any one of [9] to [11], which satisfies the requirement (i) or (ii).
Requirement (i): When the thickness of the wavelength conversion layer is 11.8 μm or more, the diameter of the mandrel (mm) where the crack that satisfies the following formula is satisfied / the thickness of the wavelength conversion layer (μm) ≦ 0.17 is satisfied.
Requirement (ii): When the thickness of the wavelength conversion layer is less than 11.8 μm, no crack occurs in the wavelength conversion layer even when a mandrel having a diameter of 2 mm is used.

[13] In the wavelength range of 520 to 560 nm and the wavelength range of 600 to 700 nm, the average values of the respective transmittances when measured from the vertical direction of the wavelength conversion layer are both 70% or more, [9] to [9] 12]. The wavelength conversion layer according to any one of [12].

[14] including a step of forming a layer using the phosphor particles (A) and a component that becomes the light diffusing material (B ′) in the resulting layer,
[11] The method for producing a wavelength conversion layer according to any one of [13].

According to one embodiment of the present invention, a film, a molded product, and a wavelength conversion layer (hereinafter also referred to as “film etc.”) having low toxicity and high luminous efficiency can be easily formed. It is possible to easily form a film having high luminous efficiency and having excellent durability and capable of maintaining the luminous efficiency even after heating.
In particular, according to an embodiment of the present invention, as described above, a film having high luminous efficiency can be formed. Therefore, even if the film is thinned, the amount of phosphor particles in the film is reduced. However, it is possible to secure a light emission amount corresponding to an increase in the amount of light incident on the phosphor particles.

In addition, according to an embodiment of the present invention, a wavelength conversion layer having high luminous efficiency and low moisture absorption can be easily obtained, and furthermore, a wavelength conversion layer having excellent bending resistance can be easily obtained. be able to.

≪Phosphor particle-containing composition≫
The phosphor particle-containing composition (hereinafter also referred to as “the present composition”) according to an embodiment of the present invention includes phosphor particles (A), hollow particles (B), and an organic solvent (C),
The composition A, wherein the phosphor particles (A) contain In, or
The hollow particle (B) is an organic hollow particle, which is a composition B.
Such a composition has the above-mentioned effects, and when QD is used as the phosphor particles (A), the QD is an expensive material. It is possible to simultaneously achieve two trade-off requirements that one wants to secure.

According to the present composition, the phosphor particles (A), in particular, the QD emission amount depends on the incident light amount, so that the increase in the incident light amount is desired. Since the hollow particles (B) are used, the amount of light incident on the phosphor particles (A) can be increased by the light diffusing effect of the particles (B). Further, the hollow particles (B) can emit light. It is conceivable that the light can be diffused efficiently.

<Phosphor particles (A)>
The phosphor particles (A) (hereinafter also referred to as “particles (A1)”) used in the composition B and the following main layer are not particularly limited, and conventionally known phosphor particles can be used. The phosphor particles (A) used for the product A (hereinafter also referred to as “particles (A2)”) are not particularly limited as long as In is included, and conventionally known phosphor particles can be used.
The particle (A) used in the present composition may be one type or two or more types.

Examples of the particles (A1) include particles used for wavelength conversion of light-emitting devices such as LEDs. Specifically, (Sr, Ca) S: Eu, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, (Y, Gd) ₃ _{Al 5} O ₁₂ : Ce, CaGa ₂ S ₄ : Eu, (Ca, Sr) ₂ Si ₅ N ₈ : Eu, SrSiO ₂ N ₂ : Eu, CaSiN ₂ : Eu, Ca ₃ _{_{_{sc 2 Si 3 O 12: Ce}}} , CaGa 2 S 4: Eu, 2SiO 4: particles made of Eu and the like.

The average particle diameter of the particles (A) is preferably 1 to 1000 nm from the viewpoint that a film having high luminous efficiency can be easily obtained, and the specific surface area is increased to improve the fluorescence characteristics. The thickness is more preferably 3 to 300 nm from the viewpoint that it can be suitably used for a thin film.

Among the particles (A), the particle (A) is preferably a so-called QD which is a small lump of about several tens of nanometers in which several hundred or more semiconductor atoms are gathered, and is a semiconductor formed using a semiconductor material. More preferably, it is a quantum dot.
QD can easily change the energy state of electrons by changing its size, can freely control the emission wavelength, has higher photostability (long life) than existing dyes, has a fluorescence wavelength of Because it is sharp and has little overlapping of wavelengths, it is suitable for multiple staining, and it has a broad absorption spectrum and is continuous, so it can be excited at any wavelength shorter than the fluorescence wavelength. Therefore, it is preferable.

The QD is not particularly limited as long as it is a particle that emits fluorescence when irradiated with light, but includes a group 2 element, a group 11 element, a group 12 element, a group 13 element, a group 14 element, a group 15 element or a group 16 element. Is preferred.

Specific examples of such elements include Be (beryllium), Mg (magnesium), Ca (calcium), Sr (strontium), Ba (barium), Cu (copper), Ag (silver), and gold (Au ), Zinc (Zn), Cd (cadmium), Hg (mercury), B (boron), Al (aluminum), Ga (gallium), In (indium), Tl (thallium), C (carbon), Si (silicon) ), Ge (germanium), Sn (tin), Pb (lead), N (nitrogen), P (phosphorus), As (arsenic), Sb (antimony), Bi (bismuth), O (oxygen), S (sulfur) ), Se (selenium), Te (tellurium), Po (polonium). Among these, QD containing In as a constituent element is preferable from the viewpoint that it is low toxic, safe, and can easily form a film having excellent light emission characteristics.

The QD more preferably contains at least two elements selected from the above elements. For example, a group II-VI semiconductor compound, a group III-V semiconductor compound, a group IV-VI semiconductor compound, a group IV element Or it is more preferable that the compound containing this, the combination of these, etc. are included.

The II-VI group semiconductor compound that can be used as the particles (A1) is selected from the group consisting of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, and mixtures thereof. Original compound: CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, H Original compounds; and CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnST And quaternary compounds selected from the group consisting of mixtures thereof.

Examples of the group III-V semiconductor compound that can be used as the particles (A1) and (A2) include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and mixtures thereof. A binary compound selected from the group consisting of: selected from the group consisting of GNP, GNAs, GNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb and mixtures thereof As well as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlN s, InAlNSb, InAlPAs, InAlPSb and quaternary compounds selected from the group consisting of mixtures thereof.

Examples of the IV-VI group semiconductor compound that can be used as the particles (A1) include binary compounds selected from the group consisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe, and mixtures thereof; SnSeS, SnSeTe, SnSTe Ternary compounds selected from the group consisting of PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe and mixtures thereof; and quaternary compounds selected from the group consisting of SnPbSSSe, SnPbSeTe, SnPbSTe and mixtures thereof, etc. Can be mentioned.

The group IV element that can be used as the particles (A1) or a compound containing the same is selected from the group consisting of Si, Ge and mixtures thereof; and the group consisting of SiC, SiGe and mixtures thereof Binary compounds selected from the above.

QD is a QD that does not use Cd or Pb as a constituent element, for example, In or Si, etc., particularly In. QD contained as is preferred.
Conventionally, phosphor particles containing Cd have been used from the standpoint that a layer having excellent luminous efficiency can be obtained. However, due to the recent increase in safety requirements, phosphor particles containing toxic Cd. Is not required. However, for example, it has been found that phosphor particles containing In tend to have lower luminous efficiency of the resulting film or the like than phosphor particles containing Cd. As a result of intensive studies by the present inventor on such problems, it is found that according to the composition A, a film having a luminous efficiency comparable to or higher than that of the conventional film can be obtained while having low toxicity. I found it.

QD includes a compound (a) having a fluorescence maximum in a wavelength region of 490 to 600 nm, particularly 520 to 560 nm and / or a compound (b) having a fluorescence maximum in a wavelength region of 600 to 750 nm, particularly 600 to 700 nm. It is preferable.
When the QD contains the compound (a) and / or the compound (b), the present composition displays an image using a device that efficiently converts the wavelength of light from a light source, for example, visible light. It can be suitably used as a composition for forming a light emitting layer of a light emitting display element, a color tone adjusting layer of LED or fluorescent lamp illumination, a light receiving conversion layer of a photovoltaic power generation panel, and the like.

The structure of QD is not particularly limited, but may be a core-shell structure type composed of two or more compounds, or a homogeneous structure type composed of one compound such as AgInS ₂ and Zn-doped AgInS _2. The core-shell structure type is preferable.
In the core-shell structure type QD, for example, by covering a core semiconductor with a semiconductor having a larger band gap, excitons (electron-hole pairs) generated by photoexcitation can be confined in the core. As a result, by using the core-shell structure type QD, the probability of non-radiative transition on the surface of the QD is reduced, and a film having high luminous efficiency and excellent stability of light emission characteristics (long life) can be easily obtained. Can do.

The core material in the core-shell structure type QD is not particularly limited, but InP, CuInS ₂ , (ZnS / AgInS ₂ ) solid solution, CdSe, CdS, ZnS, ZnSe, CdTe, CdSeTe, CdZnS, PbSe, AgInZn ₂ , AgInZnS And one or more selected from ZnO and the like. Among these, a core material containing In is preferable because it is low in toxicity, safe, and can easily form a film having excellent light emission characteristics.

The material of the shell in the core-shell structure type QD is not particularly limited, but one type selected from CdSe, ZnSe, ZnS, (ZnS / ZnSe) solid solution, ZnSeS, ZnTe, CdTe, PbS, TiO, SrSe, and HgSe. Or 2 or more types are mentioned.

Specific examples of the core-shell structure type QD include InP / ZnS compounds, InP / ZnSe compounds, InP / ZnSe / ZnS compounds, InP / (ZnS / ZnSe) solid solution compounds, InP / ZnSeS compounds, and CuInS ₂ / ZnS compounds. And (ZnS / AgInS ₂ ) solid solution / ZnS compounds are preferred, and InP / ZnS and InP / ZnSe / ZnS compounds are more preferred.
In an InP / ZnSe / ZnS compound or the like, since ZnSe has a smaller lattice constant difference than InP, ZnS can be prevented from causing defects in the core-shell structure by providing ZnSe as an intermediate layer.
InP / ZnS is QD with InP as the core and ZnS as the shell. The same applies to other core-shell structure type QDs.

As the particles (A), the InP / ZnS compound, InP / ZnSe compound, InP / ZnSe / ZnS compound, InP / (ZnS / ZnSe) solid solution compound, InP / ZnSeS compounds, CuInS ₂ / ZnS compounds, AgInS ₂ compounds, (ZnS / AgInS ₂ ) solid solution / ZnS compounds and Zn-doped AgInS ₂ compounds are preferred.

QD may be obtained by synthesis by a conventionally known method, or a commercially available product may be used.
The QD synthesis method is not particularly limited. For example, in the core-shell structure type QD, for example, after synthesizing the core, a precursor for forming a shell in the obtained reaction system is added to the core surface. It can be obtained by forming a shell.
InP / ZnS, which is a core-shell structure type QD, can also be synthesized by referring to the method described in “Chem. Mater., 2015, 27 (13), pp 4893-4898”, for example. .

In addition, QD obtained by a conventionally known method is usually a particle composed of an inorganic component such as InP / ZnS and an organic component stabilizing the component.

The average particle diameter of QD may be appropriately selected according to the desired fluorescence wavelength, but can be easily synthesized, and in particular, a film having high luminous efficiency can be easily obtained. The thickness is preferably 2 to 10 nm, and more preferably 2 to 8 nm from the viewpoint that particles having a fluorescence peak wavelength in the visible light range can be easily obtained.
The QD having such an average particle diameter can be obtained, for example, by adjusting the reaction temperature, reaction time, etc. when synthesizing QD.
The average particle diameter of the QD is measured by observation with a transmission electron microscope.

The maximum fluorescence wavelength (wavelength at the peak top in the fluorescence spectrum) of the particles (A) is preferably 350 to 800 nm, more preferably 490 to 750 nm, or 520 to 560 nm and 600 to 700 nm.
By using a film containing such particles (A), a device having excellent display quality can be easily obtained.

The half width of the particle (A) (width at half height of the peak having a peak top in the fluorescence spectrum) is preferably from the viewpoint that the fluorescence wavelength is sharp, the wavelength overlap is small, and suitable for multiple staining. It is 30 to 80 nm, and more preferably 30 to 60 nm.
Specifically, the maximum fluorescence wavelength and the full width at half maximum are measured by the methods described in Examples below.

The content of the particles (A) with respect to the solid content in the composition can secure a light emission amount by increasing the amount of light incident on the particles (A) by using a small amount of the particles (A), and reducing the thickness. From the standpoint that it can be suitably used for a coated film, etc., it is preferably 0.1 to 30% by mass, more preferably 1 to 30% by mass, further preferably 2 to 25% by mass, and particularly preferably 5 to 20% by mass. %.

The content of the particles (A) is preferably 10 to 6000 parts by mass, more preferably 10 to 300 parts by mass, further preferably 20 to 300 parts by mass, and more preferably 20 to 200 parts by mass with respect to 100 parts by mass of the particles (B). 200 parts by mass, particularly preferably 50 to 200 parts by mass.
When the content of the particles (A) is in the above range, a film or the like in which physical properties such as light emission efficiency and shape are hardly changed even in a severe environment such as high temperature and high humidity can be easily obtained. . Moreover, even if the content of the particles (A) is in the above range, the amount of light emitted by the amount of light incident on the particles (A) can be secured, so the content of the particles (A) is in the above range. As a result, the requirements of the cost and the amount of light emission can be satisfied simultaneously.
In addition, when there is too much content of particle | grains (A), it exists in the tendency for the transmittance | permeability of the film | membrane etc. which are obtained to fall, and when there is too little content, it exists in the tendency for light emission amounts, such as a film | membrane obtained, to be too little.

<Hollow particles (B)>
The hollow particles (B) used in the composition A (hereinafter also referred to as “particles (B1)”) are not particularly limited as long as they have pores therein, and the hollow particles used in the composition B ( B) (hereinafter also referred to as “particle (B2)”) is not particularly limited as long as it is an organic hollow particle having pores therein.
By using such particles (B), the amount of light incident on the particles (A) can be increased, and further, the emitted light from the particles (A) can be efficiently diffused, which is high. A film having luminous efficiency can be easily obtained. Even if the film is thinned or the amount of phosphor particles in the film is reduced, the amount of light incident on the particles (A) is increased. A light emission amount can be secured. Furthermore, the film | membrane etc. which are excellent in bending resistance can be easily obtained by using particle | grains (B).
The particle (B) used in the present composition may be one type or two or more types.

The particles (B1) are not particularly limited and may be inorganic hollow particles or organic hollow particles, but organic hollow particles are preferable.
The particles (B) are preferably mixed with other organic components (such as an organic solvent (C) and a binder used as necessary) to maintain a uniform dispersed state as a composition, and maintain a uniform dispersed state. From the standpoint that the composition can be easily obtained, organic hollow particles are preferred. Furthermore, the organic hollow particles are preferable because they have a high degree of freedom in adjustment such as molecular design and synthesis in accordance with other constituent materials in the composition. In addition, organic hollow particles having a high toluene insoluble content (90% by mass or more) have the same degree of hardness as inorganic hollow particles, and therefore have the above characteristics and retain voids when subjected to deformation due to thermal stress or the like. Excellent in properties.

The inorganic hollow particles are not particularly limited, and inorganic particles composed of Al ₂ O ₃ , SiO ₂ , ZnO, ZrO ₂ , TiO ₂ , ITO, ATO, SnO, CeO ₂ , CaCO ₃ , polyorganosiloxane compounds, and the like From the standpoint of particles having low hygroscopicity and excellent dispersibility in an organic solvent, particles obtained by subjecting at least a part of the surface to surface treatment, particularly hydrophobic treatment, are preferable.
As such inorganic hollow particles, commercially available products may be used, or they may be synthesized by a conventionally known method, for example, the method described in Japanese Patent No. 5078620.

The organic hollow particles are not particularly limited, and examples thereof include organic crosslinked particles such as acrylic or styrene.
As such organic hollow particles, commercially available products may be used, and conventionally known methods such as JP-A-62-2127336, JP-A-01-315454, JP-A-4-126771, They may be synthesized by the methods described in JP-A No. 2002-241448, JP-A No. 2007-112935, and Japanese Patent No. 5439102.

As the organic hollow particles, particles having high light diffusibility, excellent organic solvent resistance and shape retention are obtained, the present composition having excellent long-term stability is obtained, and a film having high luminous efficiency is further obtained. From the viewpoint that it can be easily obtained, crosslinked hollow polymer particles obtained by the following method, specifically, the method described in Japanese Patent No. 4844850 are preferred.

(Method)
The following polymerizable monomer (α) is emulsion-polymerized in an aqueous medium to prepare a dispersion of first polymer particles, and then the surface layer of the first polymer particles is a second polymer derived from the following polymerizable monomer (β) and A core-shell particle dispersion coated with a shell layer containing an unreacted polymerizable monomer (β) is prepared, and then the pH of the core-shell particle dispersion is set to 7 or more (25 ° C. converted value) with a volatile base such as ammonia. ) And neutralizing and swelling the core-shell particles to prepare crosslinked hollow polymer particles (aqueous dispersion).

As the polymerizable monomer (α), an unsaturated carboxylic acid (α-1), a radical polymerizable monomer (α-2), or the like is used.

Examples of the unsaturated carboxylic acid (α-1) include mono- or dicarboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, and itaconic acid, and acid anhydrides of the dicarboxylic acid.

Examples of the monomer (α-2) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and the like, styrene , Aromatic monomers such as α-methylstyrene, (meth) acrylonitrile, vinyl acetate, N, N-dimethyl (meth) acrylamide and the like.

The method for preparing the core-shell particle dispersion can be specifically performed based on the following method.
In the presence of 5 to 1000 parts by mass of the first polymer particles, 100 parts by mass of the polymerizable monomer (β) is emulsion-polymerized in an aqueous solvent, and the surface layer of the first polymer particles is converted into the second polymerizable monomer (β). A method of coating with a shell layer containing the derived second polymer and an unreacted polymerizable monomer (β).

The polymerizable monomer (β) is 10 to 80% by mass of a crosslinkable radical polymerizable monomer (β-1), 0 to 20% by mass of an unsaturated carboxylic acid (β-2), and 0 to 90% by mass. The other radical polymerizable monomer (β-3) copolymerizable with the monomer (β-1) is used.

Examples of the monomer (β-1) include polyethylenic compounds such as divinylbenzene, trivinylbenzene, dicyclopentadiene, butadiene, isoprene, and ethylene glycol di (meth) acrylate.

Examples of the monomer (β-2) include the same compounds as the unsaturated carboxylic acid (α-1) described above. Among them, (meth) acrylic acid, itacone is preferable from the viewpoint of the stability of the obtained particles. An acid or the like is preferable.

Examples of the monomer (β-3) include monoethylenic aromatic compounds such as styrene and α-methylstyrene, compounds similar to the unsaturated carboxylic acid ester in the above (α-2), stearyl (meth) acrylate, dodecyl Non-crosslinking radically polymerizable monomers such as unsaturated carboxylic acid esters such as (meth) acrylate and 2-ethylhexyl (meth) acrylate, (meth) acrylonitrile, vinyl acetate and N, N-dimethyl (meth) acrylamide Of these, monoethylenic aromatic compounds such as styrene are preferred.

When the particle (B) has a carboxy group, a thiol group, an amino group or the like on its surface, the interaction with the particle (A), in particular, QD is increased, and this composition having excellent stability can be easily obtained. Further, it is considered that oxygen, moisture, residual monomers and the like that cause a decrease in QD fluorescence quantum yield can be prevented from adhering to the surface.
The particles (B) having such a surface may synthesize particles having these groups using a monomer having a carboxy group, a thiol group or an amino group as the polymerizable monomer (β), You may surface-treat the surface of the particle | grains obtained by the commercial item or the said (previously well-known) method by the conventionally well-known method using the compound which has these groups.

Particles (B) have voids inside, but the number of voids may be plural, but is preferably one, and more preferably has one void at the approximate center.

The average particle diameter (outer diameter) of the particles (B) is preferably 0.02 to 5 μm, more preferably 0.02 to 3 μm from the viewpoint that a film having high luminous efficiency can be easily obtained. From the point that it can be suitably used for a thinned film or the like, it is preferably 0.1 to 2 μm, more preferably 0.1 to 1 μm, still more preferably 0.3 to 1 μm, and particularly preferably 0.8. 3 to 0.5 μm.

The diameter (inner diameter) of the largest void contained in the particles (B) is preferably 0.01 μm or more, more preferably 0 from the viewpoint that a film having high luminous efficiency can be easily obtained. 0.02 to 2 μm.
When the particle (B) has one void, the inner diameter is measured by the method described in the following example, but when the particle (B) has a plurality of voids, the void portion of the particle in the TEM photograph And the diameter (inner diameter) of the void is obtained by regarding the particle as one particle having one void having this area.

The particle diameter variation coefficient (CV = standard deviation / outer diameter) of the particles (B) is preferably 10% or less from the viewpoint that a film having uniform light emission characteristics can be easily obtained with high productivity. More preferably, it is 5% or less, and more preferably 3% or less. In addition, since a CV value is so preferable that it is small, the minimum in particular is not restrict | limited, For example, it is 1%.

The average film thickness of the shell of the particles (B) (average film thickness of the substance surrounding the void) is high in light diffusibility, and particles excellent in organic solvent resistance and shape retention are obtained, and have high luminous efficiency. Moreover, the thickness is preferably 0.005 to 0.1 μm, more preferably 0.01 to 0.1 μm, from the viewpoint that a film that can maintain the luminous efficiency for a long time can be easily obtained.
The particle shell refers to a portion other than the internal void in the cut surface when the particle is cut.
In addition, when the particle (B) has one void, the average film thickness of the shell is measured by the method described in the following example, but when the particle (B) has a plurality of voids, After determining the total area of the voids of the particles, assuming that the particles have one void having this area, and determining the diameter (inner diameter) of the voids, the outer diameter measured by the method described in the examples below The average film thickness of the shell is calculated from the difference between this and the inner diameter.

The value of the shell thickness / outer diameter of the particles (B) is preferably 0.05 to 1 and more preferably 0.1 to 0.3 from the viewpoint of retention stability of voids.

The porosity of the particles (B) is preferably 4 to 70%, more preferably 40 to 40% from the viewpoint that particles having high light diffusibility can be obtained and a film having high luminous efficiency can be easily obtained. 65%, more preferably 40-60%.

The outer diameter, CV, inner diameter, shell thickness and porosity can be measured by the methods described in the following examples.

The toluene-insoluble content of the particles (B) is preferably 80 to 100% by mass, more preferably 90 to 100% by mass, and particularly preferably 94 from the viewpoint that a film having high luminous efficiency can be easily obtained. To 100% by mass.
When the toluene insoluble content is less than 80% by mass, deformation of the hollow particles occurs, and foreign matters are easily generated. Therefore, a film having high luminous efficiency cannot be obtained, and the obtained film or the like is optical. Unevenness (bright spot) tends to occur.
The toluene-insoluble content refers to the amount that remains without being dissolved when the particles (B) are immersed in toluene, and specifically, is measured by the method described in the examples below.

Incidentally, the reason why toluene was used as the organic solvent for measuring the insolubility of the particles (B) is that toluene was generally used in the composition containing the phosphor particles, and its reproducibility was good.

The heat resistance temperature (5% mass reduction temperature) of the particles (B) can provide a film having excellent heat resistance, and can retain its shape (void) sufficiently even when the temperature rises depending on the molding and application. In the case of organic hollow particles, the temperature is preferably 180 to 400 ° C., more preferably 250 to 350 ° C. from the viewpoint that a film that can maintain high luminous efficiency over a long period of time can be easily obtained.
The heat-resistant temperature can be measured by the method described in the following examples.

The content of the particles (B) is preferably with respect to 100% by mass of the present composition from the viewpoints of having a high luminous efficiency and easily obtaining a film that can maintain the luminous efficiency over a long period of time. Is 0.1 to 20% by mass, more preferably 0.5 to 10% by mass.

<Organic solvent (C)>
From the point that a film having a desired thickness or the like can be easily formed from the composition, and from the viewpoint that both the particles (A) and the particles (B) can maintain a good dispersion state, Solvent (C) is used. In addition, when using the dispersion liquid containing an organic solvent as particle | grains (A) and particle | grains (B), the organic solvent in this dispersion liquid is the organic solvent (C) in this composition.
Although it does not restrict | limit especially as said organic solvent (C), The solvent which does not melt | dissolve particle | grains (A) and particle | grains (B) (surface), but can disperse | distribute particle | grains (A) and particle | grains (B) is preferable.
The solvent (C) used in the present composition may be one type or two or more types.

Examples of the hydrocarbon solvent include aliphatic hydrocarbon solvents such as pentane, hexane, i-hexane, heptane, octane, cyclohexane, and methylcyclohexane; aromatic carbonized solvents such as benzene, toluene, xylene, mesitylene, ethylbenzene, and methylethylbenzene. Examples thereof include hydrogen-based solvents.

Examples of the ether solvent include diethyl ether, dipropyl ether, 1,2-propylene glycol-1-methyl ether-2-acetate, 1,3-butanediol-1-acetate-3-methyl ether, and 3-methoxybutanol. 1,2-propylene glycol-1-methyl ether, 1,2-propylene glycol-1-ethyl ether, diethylene glycol monopropyl ether, di (1,3-propylene glycol) -1-monomethyl ether, 3-ethoxybutanol, Fats such as 3-hydroxypropionic acid-1-ethyl ester-3-ethyl ether, 3-hydroxypropionic acid-1-methyl ether-1-methyl ester, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether Family ethers; anisole, aromatic such as phenyl ether - aliphatic ethers; di aromatic ethers such as diphenyl ether; tetrahydrofuran, tetrahydropyran, cyclic ethers such as dioxane and the like.

Examples of the ester solvent include carbonates such as diethyl carbonate and propylene carbonate; lactones such as γ-butyrolactone and γ-valerolactone; acetates such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate, benzyl acetate, and cyclohexyl acetate; And propionic acid esters such as ethyl propionate and butyl propionate.

Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-i-butyl ketone, 2-heptanone, ethyl-n-butyl ketone, methyl-n-hexyl ketone, Chain ketone solvents such as di-i-butyl ketone, trimethylnonanone, 2,4-pentanedione, and acetonyl acetone; cyclic ketones such as cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, methylcyclohexanone, and acetophenone System solvents and the like.

Examples of the solvent (C) include 1,2-propylene glycol-1-methyl ether-2-acetate, 1,3-butanediol-1-acetate-3-methyl ether, from the viewpoint of coating properties and dispersibility effects. 3-methoxybutanol, 1,2-propylene glycol-1-methyl ether, 1,2-propylene glycol-1-ethyl ether, diethylene glycol monopropyl ether, di (1,3-propylene glycol) -1-monomethyl ether, cyclohexanone 3-ethoxybutanol, 3-hydroxypropionic acid-1-ethyl ester-3-ethyl ether, 3-hydroxypropionic acid-1-methyl ether-1-methyl ester, diethylene glycol dimethyl ether and diethylene glycol methyl ethyl ether Masui.

The average boiling point of the solvent (C) at normal pressure is preferably 100 to 250 ° C. from the viewpoint that a desired film or the like can be easily formed from the present composition. The average boiling point is synonymous with the boiling point of the solvent when one kind of solvent is used as the solvent (C). For example, when two kinds of solvents (solvent 1 and solvent 2) are used. Is a value calculated by the following equation. The same applies when three or more solvents are used.
Average boiling point = {boiling point of solvent 1 × content of solvent 1 / (sum of contents of solvents 1 and 2) + boiling point of solvent 2 × content of solvent 2 / (sum of contents of solvents 1 and 2)} / 2

The content of the solvent (C) may be appropriately selected according to the formation method when forming a film or the like from the present composition, but the particles (A) and particles (B) can be sufficiently dispersed. From this point, the amount is preferably 100 to 30000 parts by mass, more preferably 500 to 20000 parts by mass with respect to 100 parts by mass of the particles (B).

<Binder>
The present composition preferably contains a binder from the viewpoint that a film or the like that can sufficiently hold the particles (A) and (B) can be formed.
1 type may be used for a binder and 2 or more types may be used for it.

The binder is not particularly limited, and may be a monomer or a resin, but is preferably a component that is cured by light or heat, and a component that hardly undergoes curing shrinkage during the curing. It is more preferable that For this reason, the binder may be an ion curable component, but is preferably a radical curable component, and a compound having an alkyl chain having 5 or more carbon atoms is preferable. In addition, a compound having an acidic functional group such as a carboxy group or a phenolic hydroxyl group from the standpoint that the present composition having an enhanced interaction with the particles (A), in particular, QD, and excellent stability can be easily obtained. It is preferable that
Further, as the binder, a binder excellent in transparency, curability, co-dispersibility with the particles (A) and (B), and hollow retention of the particles (B) (does not fill the voids in the particles (B)) is preferable. A binder capable of imparting water or oxygen barrier properties to the film or the like is preferable.

As the binder, even when a film or the like obtained from the composition is used in a high-temperature environment, it is possible to easily obtain a film or the like that can maintain a sufficient shape (void) and maintain high luminous efficiency over a long period of time. In view of the above, it is preferable to use a component capable of forming a crosslinked structure, and (meth) acrylate binders and epoxy binders are preferred.

As the (meth) acrylate-based binder, any of a monofunctional monomer, a bifunctional monomer, and a polyfunctional monomer may be used, but it is preferable to use a bifunctional or higher (meth) acrylic ester. .

Examples of the monofunctional monomer include 2- (meth) acryloyloxyethyl succinic acid, nonylphenyl carbitol acrylate, 2-ethylhexyl carbitol acrylate, isostearyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate (trade name “ New Frontier PGA ", manufactured by Daiichi Kogyo Seiyaku Co., Ltd.).

Examples of the bifunctional monomer include 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, and 9,9-bis [4- (2- (meth) acryloyl). Oxyethoxy) phenyl] fluorene, tricyclodecane dimethanol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, bis ((meth) acryloyloxyethyl) ether of bisphenol A, 3-ethylpentanediol di (Meth) acrylate, phenylglycidyl ether acrylate, hexamethylene diisocyanate, urethane prepolymer, bis (2- (meth) acryloyloxyethyl) acid phosphate (trade name “KAYAMER PM-2”, manufactured by Nippon Kayaku Co., Ltd.) Is given.

Examples of the polyfunctional monomer include ethoxylated isocyanuric acid tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol di (meth) acrylate, and dipentaerythritol tris. (Meth) acrylate, dipentaerythritol penta (meth) acrylate, ethoxylated dipentaerythritol hexa (meth) acrylate, propoxylated dipentaerythritol hexa (meth) acrylate, dipentaerythritol hexa (meth) acrylate, represented by the following formula Compounds such as dipentaerythritol (poly) acrylate, dipentaerythritol pentaacrylate, urethane prepolymer, bisphenol A epoxy diacrylate (Trade name "CN104", manufactured by Arkema Co., Ltd.) is Kyora.

(In the formula, R is a hydrogen atom or an acryloyl group having 3 to 6 carbon atoms.)

As an epoxy binder, an aliphatic compound having a three-membered ring epoxy group, an alicyclic compound having a three-membered ring epoxy group, an aromatic compound having a three-membered ring epoxy group, a four-membered ring epoxy group (oxetanyl group) Any of the compounds may be used.

Examples of the aliphatic compound having a three-membered ring epoxy group include 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, and trimethylolpropane triglycidyl ether. It is done. Examples of commercially available products include SR-NPG and SR-TMP (manufactured by Sakamoto Pharmaceutical Co., Ltd.).

Examples of alicyclic compounds having a three-membered ring epoxy group include 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate, 2- (3,4-epoxycyclohexyl-5,5-spiro. -3,4-epoxy) cyclohexane-meta-dioxane, bis (3,4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 3,4-epoxy-6-methyl Cyclohexyl-3 ′, 4′-epoxy-6′-methylcyclohexanecarboxylate, ε-caprolactone modified 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate, trimethylcaprolactone modified 3,4-epoxycyclohexyl Methyl-3 , 4'-epoxycyclohexanecarboxylate, β-methyl-δ-valerolactone modified 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate, di (3,4-epoxycyclohexylmethyl) of ethylene glycol Examples include ether, ethylenebis (3,4-epoxycyclohexanecarboxylate), dioctyl epoxycyclohexahydrophthalate, di-2-ethylhexyl epoxycyclohexahydrophthalate, and methylenebis (3,4-epoxycyclohexane).

Examples of commercially available alicyclic compounds having a three-membered ring epoxy group include Adeka Resin EP-4085S, EP-4088S (above, manufactured by ADEKA Corporation), Celoxide 2021, Celoxide 2021P, Celoxide 2081, Celoxide 2083, Celoxide. 2085, Epolide GT-300, Epolide GT-301, Epolide GT-302, Epolide GT-400, Epolide 401, Epolide 403 (manufactured by Daicel Corporation).

Examples of the aromatic compound having a three-membered ring epoxy group include compounds having an aromatic ring structure in the skeleton and having two or more three-membered ring epoxy groups. Examples of the aromatic ring structure of such a compound include a bisphenol A structure, a bisphenol F structure, and a naphthalene skeleton. Examples of aromatic compounds having a three-membered ring epoxy group include bis (4-glycidylphenoxy) methane, bis (4-glycidylphenoxy) ethane, bis (4-glycidylnaphthoxy) methane, and bis (4-glycidylnaphthoxy). Ethane and the like can be mentioned. Examples of commercially available aromatic compounds having a three-membered ring epoxy group include YL980, YL983U (manufactured by Mitsubishi Chemical Corporation), EPICLON® HP-7200, EXA-4850-150, HP-4770, (and DIC Corporation).

Examples of the compound having a four-membered ring epoxy group (oxetanyl group) include compounds having one or more oxetanyl groups in the molecule. Examples of the compound having one oxetanyl group include 3-ethyl-3-hydroxymethyloxetane, 3- (meth) allyloxymethyl-3-ethyloxetane, (3-ethyl-3-oxetanylmethoxy) methylbenzene, 4-fluoro- [1- (3-ethyl-3-oxetanylmethoxy) methyl] benzene, 4-methoxy- [1- (3-ethyl-3-oxetanylmethoxy) methyl] benzene, [1- (3-ethyl- 3-oxetanylmethoxy) ethyl] phenyl ether, isobutoxymethyl (3-ethyl-3-oxetanylmethyl) ether, isobornyloxyethyl (3-ethyl-3-oxetanylmethyl) ether, isobornyl (3-ethyl-3- Oxetanylmethyl) ether, 2-ethylhexyl (3-ethyl-3 Oxetanylmethyl) ether, ethyl diethylene glycol (3-ethyl-3-oxetanylmethyl) ether, dicyclopentadiene (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenyloxyethyl (3-ethyl-3-oxetanylmethyl) ether Dicyclopentenyl (3-ethyl-3-oxetanylmethyl) ether, tetrahydrofurfuryl (3-ethyl-3-oxetanylmethyl) ether, tetrabromophenyl (3-ethyl-3-oxetanylmethyl) ether, 2-tetrabromo Phenoxyethyl (3-ethyl-3-oxetanylmethyl) ether, tribromophenyl (3-ethyl-3-oxetanylmethyl) ether, 2-tribromophenoxyethyl (3-ethyl-3-oxetanylmethyl) ) Ether, 2-hydroxyethyl (3-ethyl-3-oxetanylmethyl) ether, 2-hydroxypropyl (3-ethyl-3-oxetanylmethyl) ether, butoxyethyl (3-ethyl-3-oxetanylmethyl) ether, penta Examples include chlorophenyl (3-ethyl-3-oxetanylmethyl) ether, pentabromophenyl (3-ethyl-3-oxetanylmethyl) ether, and bornyl (3-ethyl-3-oxetanylmethyl) ether.

Examples of the compound having two or more oxetanyl groups include 3,7-bis (3-oxetanyl) -5-oxa-nonane, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, 1,2-bis [(3-ethyl-3-oxetanylmethoxy) methyl] ethane, 1,2-bis [(3-ethyl-3-oxetanylmethoxy) methyl] propane, ethylene glycol bis (3-ethyl-3- Oxetanylmethyl) ether, dicyclopentenyl bis (3-ethyl-3-oxetanylmethyl) ether, triethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, tetraethylene glycol bis (3-ethyl-3-oxetanylmethyl) ) Ether, Tricyclodecanediyldimethylenebis (3-ethyl-3) Oxetanylmethyl) ether, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] butane, 1,6-bis [(3-ethyl-3-oxetanylmethoxy) methyl] hexane, 3-ethyl-3 {[(3-ethyloxetane-3-yl) methoxy] methyl} oxetane.

The binder may be a binder resin.
The binder resin is preferably a transparent resin in the visible light region or a resin capable of forming the resin. For example, an organic resin such as a (meth) acrylic resin, an inorganic resin such as polysiloxane, and a (meth) acrylsiloxane Organic / inorganic hybrid resins such as resins and epoxy silicon resins can be used. Examples of the resin include resins described in JP2008-260930A, JP2009-102514A, and the like.

The binder resin is preferably a resin having an acidic functional group such as a carboxy group or a phenolic hydroxyl group. Among them, a polymer having a carboxy group (hereinafter also referred to as “carboxy group-containing polymer”) is preferable. For example, an ethylenically unsaturated monomer having one or more carboxy groups (hereinafter referred to as “unsaturated monomer”). And the other ethylenically unsaturated monomers copolymerizable with the monomer (hereinafter also referred to as “unsaturated monomer (c2)”). Coalescence can be mentioned.

Specific examples of the copolymer of the unsaturated monomer (c1) and the unsaturated monomer (c2) include, for example, JP-A-7-140654, JP-A-8-259876, and JP-A-10-31308. No. 10, JP-A-10-300902, JP-A-11-174224, JP-A-11-258415, JP-A-2000-56118, JP-A-2004-101728, etc. Coalescence can be mentioned.

In the copolymer of the unsaturated monomer (c1) and the unsaturated monomer (c2), the copolymerization ratio of the unsaturated monomer (c1) in the copolymer is preferably 5 to 70% by mass. More preferably, it is 10 to 60% by mass. By copolymerizing the unsaturated monomer (c1) in such a range, a film having excellent chromaticity characteristics, heat resistance and solvent resistance can be easily obtained, and particles (A) and (B) This composition having excellent dispersibility and excellent storage stability can be easily obtained.

Examples of the binder resin include JP-A-5-19467, JP-A-6-230212, JP-A-7-207211, JP-A-9-325494, JP-A-11-140144, As disclosed in JP 2008-181095 A or the like, a carboxy group-containing polymer having a polymerizable unsaturated bond such as a (meth) acryloyl group in the side chain may be used.

The weight average molecular weight (Mw) measured by GPC of the binder resin is preferably 1,000 to 100,000, more preferably 3,000 to 50,000. The molecular weight distribution (Mw / Mn) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0. By setting it as such an aspect, the film | membrane etc. which are excellent in chromaticity characteristics, heat resistance, and solvent resistance can be obtained easily, it is excellent in the dispersibility of particle | grains (A) and (B), and is excellent in storage stability. The present composition can be easily obtained.

The binder resin can be produced by a known method. For example, the binder resin can be produced by a method disclosed in JP2003-222717A, JP2006-259680A, International Publication No. 2007/029871, etc. The structure, Mw, and Mw / Mn can also be controlled.

As the binder, for example, an alkali-soluble resin described in JP-A No. 2015-166840 may be used from the viewpoint that a film having a desired shape can be easily obtained by development or the like. From the viewpoint that the present composition having a desired viscosity can be easily obtained, for example, a reaction diluent described in International Publication No. 2005/071014 can be used.

When the present composition contains a binder, the content of the binder has a high luminous efficiency, and can be easily formed into a film having a desired (surface) shape. In consideration of the transmittance of the composition, it is preferably 0.5 to 50% by mass, more preferably 1 to 40% by mass with respect to 100% by mass of the present composition.

<Other ingredients>
In the present composition, other components conventionally known in the field other than the particles (A), particles (B), solvent (C) and binder may be blended within a range not impairing the effects of the present invention. Good. Examples of the other components include fillers, antioxidants, polymerization initiators, acid generators, base generators, viscosity modifiers, and dispersants.
Each of the other components may be used alone or in combination of two or more.

[Filler]
The filler is not particularly limited, and a conventionally known filler can be used. However, there is a possibility that the particles (A) can be adsorbed and stabilized, and it is expected to obtain a film having stable luminous efficiency over a long period of time. From the standpoint of being able to obtain a filler capable of adsorbing or fixing the particles (A), particularly QD, a film having better luminous efficiency, and the like, a high refractive index filler is preferred.
Examples of such fillers include sols such as porous silica, titania, and zirconia.

[Antioxidant]
It does not restrict | limit especially as said antioxidant, It is preferable that it is a material which can prevent oxidation, especially the oxidation of particle | grains (A). In particular, when QD is used as the particles (A), it suppresses the generation of free radicals, which causes a reduction in the QD fluorescence quantum yield, and suppresses oxygen, moisture, or residual monomers from adhering to the QD surface. For the purpose of, for example, an antioxidant containing a phosphorus and / or sulfur atom is preferable, a compound having a phosphine structure, a compound having a phosphite structure, a compound having a thioether structure, and a compound having a thiol group are more preferable. Furthermore, it is more preferable to use a phenolic antioxidant in combination with these because heat resistance is improved.

-Antioxidant containing a phosphorus atom Examples of the antioxidant containing a phosphorus atom include a compound having a phosphine structure, a compound having a phosphite structure, and the like.

(Compound having phosphine structure)
Compounds having a phosphine structure include tri-o-tolylphosphine, tri-m-tolylphosphine, tri-p-tolylphosphine, tri-2,5-xylylphosphine, tri-3,5-xylylphosphine, tri Examples thereof include phenylphosphine and diphenyl (p-vinylphenyl) phosphine.

(Compound having phosphite structure)
Examples of the compound having a phosphite structure include tris (nonylphenyl) phosphite, tris (pt-octylphenyl) phosphite, tris [2,4,6-tris (α-phenylethyl)] phosphite, tris ( p-2-butenylphenyl) phosphite, bis (p-nonylphenyl) cyclohexyl phosphite, tris (2,4-di-t-butylphenyl) phosphite, di (2,4-di-t-butylphenyl) ) Pentaerystol diphosphite, 2,2′-methylenebis (4,6-di-t-butyl-1-phenyloxy) (2-ethylhexyloxy) phosphorus, distearyl pentaerythritol diphosphite, 4,4 ′ -Isopropylidene-diphenol alkyl phosphite (the alkyl group has 12 to 15 carbon atoms), Tratridecyl-4,4′-butylidene-bis (3-methyl-6-tert-butylphenol) diphosphite, tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylene phosphite, 2,6- Di-t-butyl-4-methylphenyl-phenyl-pentaerythritol diphosphite, 2,6-t-butyl-4-methylphenyl-phenyl-pentaerythritol diphosphite, 2,6-di-t-butyl- 4-ethylphenyl-stearyl-pentaerythritol diphosphite, di (2,6-t-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,6-di-t-amyl-4-methylphenyl-phenyl -Pentaerythritol diphosphite and the like.

As a commercial product of a compound having a phosphite structure, ADEKA Corporation's ADK STAB series, specifically, “PEP-4C”, “PEP-8”, “PEP-8W”, “PEP-24G” , “PEP-36”, “HP-10”, “2112”, “260”, “522A”, “1178”, “1500”, “C”, “135A”, “3010” and “TPP”, BASF Examples thereof include “IRGAFOS168” manufactured by Japan Corporation.

Examples of the antioxidant containing a phosphorus atom include compounds having a phosphine structure from the viewpoint of more effectively suppressing generation of free radicals that cause a decrease in the fluorescence quantum yield of particles (A), particularly QD. Tri-o-tolylphosphine, tri-2,5-xylylphosphine and triphenylphosphine are more preferable.

-Antioxidant containing a sulfur atom Examples of the antioxidant containing a sulfur atom include a compound having a thioether structure and a compound having a thiol group.

(Compound having thioether structure)
Examples of the compound having a thioether structure include dilauryl thiodipropionate, ditridecyl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, pentaerythritol tetrakis (3-lauryl thiopropionate), Pentaerythritol tetrakis (3-octadecylthiopropionate), pentaerythritol tetrakis (3-myristylthiopropionate), pentaerythritol tetrakis (3-stearylthiopropionate), 4,4-thiobis (3-methyl-6) -T-butylphenol) and the like.

Commercially available compounds having a thioether structure include ADEKA Corporation's ADK STAB series, specifically “AO-412S” and “AO-503”, Sumitomo Chemical Co., Ltd. "TPL-R", "TPM", "TPS", "TP-D" and "MB", "IRGANOXPS800FD" and "IRGANOXPS802FD" manufactured by BASF Japan K.K., manufactured by API Corporation. “DLTP”, “DSTP”, “DMTP”, “DTTP” and the like can be mentioned.

As the compound having a thioether structure, 4,4-thiobis (3- (3) is more preferable in terms of more effectively suppressing generation of free radicals that cause a decrease in the fluorescence quantum yield of the particles (A), particularly QD. Methyl-6-t-butylphenol), tetrakis [3- (dodecylthio) propionic acid] pentaerythritol, ditridecyl 3,3′-thiobispropionate, “IRGANOX 1520 L” and “IRGANOX 1726” manufactured by BASF are preferred.

(Compound having a thiol group)
A compound having a thiol group has oxygen, moisture, residual monomers, etc. that cause a decrease in the fluorescence quantum yield of QD by effectively binding to the surface of particles (A), particularly QD, by the thiol group. It can suppress adhering to the surface. Furthermore, when a compound having two or more thiol groups is used, one thiol group can be bonded to the surface of the particle (A), particularly QD, while another thiol group is bonded to the binder, and the binder and The particles (A), particularly QD, can be brought close to each other, and the adhesion of the oxygen, moisture, residual monomer, etc. to the particles (A), particularly the QD surface, can be more significantly suppressed.

The lower limit of the number of thiol groups in the compound having a thiol group is usually 1, preferably 2, preferably 3, more preferably 4, and the upper limit of the number of thiol groups is preferably 8, more preferably 6. preferable. By setting the number of thiol groups to the above lower limit or more, it is possible to effectively suppress the adhesion of particles (A), particularly QD, to the surface of oxygen, moisture, residual monomers, etc., and the number of thiol groups to be the upper limit or less. By doing so, aggregation of particles (A) can be suppressed.

Although it does not specifically limit as a compound which has a thiol group, The chain transfer agent which has a thiol group from the point which can suppress the fall of the fluorescence quantum yield of particle | grains (A) especially QD is preferable. Moreover, it is considered that the use of a chain transfer agent having a thiol group makes it easier to maintain the fluorescence intensity from the particles (A), and it is possible to more easily and reliably maintain high color reproducibility.

As the compound having a thiol group, a compound represented by the following formula (1) (hereinafter also referred to as “compound (I)”) is preferable.

In the formula (1), X is an n-valent organic group having 1 to 20 carbon atoms. R ¹ is independently an alkanediyl group having 1 to 10 carbon atoms. n is an integer of 1 to 8. Several R1 may be the same and may differ.

Examples of the organic group represented by X include an n-valent hydrocarbon group having 1 to 20 carbon atoms, a group having a divalent heteroatom-containing group between carbon-carbon of the hydrocarbon group, a hydrocarbon group, and a hetero group. Examples include a group in which part or all of the hydrogen atoms of a group having an atom-containing group are substituted with a monovalent heteroatom-containing group.

The “hydrocarbon group” includes a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. This “hydrocarbon group” may be saturated or unsaturated. The “chain hydrocarbon group” may be linear or branched. The “alicyclic hydrocarbon group” may be monocyclic or polycyclic. However, it is not necessary to be composed only of the alicyclic structure, and a part thereof may include a chain structure. “Aromatic hydrocarbon group” refers to a hydrocarbon group containing an aromatic ring structure as a ring structure. However, it is not necessary to be composed only of an aromatic ring structure, and a part thereof may include a chain structure or an alicyclic structure.

As the hydrocarbon group,
Alkanes such as methane, ethane, propane, n-butane, isobutane;
Alkenes such as ethene, propene, 1-butene, 2-butene, 2-methylpropene;
Chain hydrocarbons such as alkynes such as ethyne, propyne, 1-butyne and 2-butyne;
Monocyclic cycloalkanes such as cyclobutane, cyclopentane, cyclohexane;
Monocyclic cycloalkenes such as cyclobutene, cyclopentene, cyclohexene;
Polycyclic cycloalkanes such as norbornane, tricyclodecane and adamantane;
Alicyclic hydrocarbons such as polycyclic cycloalkenes such as norbornene and tricyclodecene;
Aromatic hydrocarbons such as benzene, toluene, xylene, naphthalene;
And a group obtained by removing n hydrogen atoms from a hydrocarbon.

Examples of the divalent hetero atom-containing group which may be contained between the carbon atoms include —O—, —S—, —NR′—, —CO—, —CS— and the like. R ′ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. The divalent heteroatom-containing group is preferably —O—.

Examples of the monovalent hetero atom-containing group that may substitute for the hydrogen atom include —OH, —SH, —NHR ′, —COR ′, —CSR ′, and the like.

The lower limit of the carbon number of the organic group represented by X is usually 1, preferably 3 and more preferably 4, and the upper limit is preferably 15, more preferably 10, and still more preferably 6.

The lower limit of n is usually 1, 2 is preferable, 3 is more preferable, 4 is more preferable, and 6 is preferable as the upper limit.

Examples of the organic group represented by X include a group represented by the following formula (X-1), a group represented by the following formula (X-2), and a group represented by the following formula (X-3). preferable.

In the formulas (X-1) to (X-3), * represents a binding site with —O— in the formula (1). In the formula (X-3), m is an integer of 1 to 5.

Examples of the alkanediyl group represented by R ¹ include methanediyl group, 1,2-ethanediyl group, 1,1-ethanediyl group, 1,3-propanediyl group, 1,2-propanediyl group, 1,1- Examples thereof include a propanediyl group and a 2,2-propanediyl group. R ¹ is preferably an alkanediyl group having 1 to 3 carbon atoms, more preferably a 1,2-ethanediyl group and a 1,2-propanediyl group.

M is preferably an integer of 1 to 4, more preferably an integer of 2 to 4, and still more preferably 3.

Compound (I) is a compound represented by the following formula from the viewpoint of more effectively suppressing the adhesion of oxygen, moisture, residual monomer, etc. to the surface of particles (A), particularly QD. Is preferred.

-Antioxidant containing phosphorus atom and sulfur atom Examples of the peroxide decomposer containing phosphorus and sulfur include trilauryl trithiophosphite, tributyl trithiophosphite, triphenyl trithiophosphite and the like.

・ Phenolic antioxidants Examples of phenolic antioxidants include styrenated phenol, 2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butyl-p-ethylphenol, 2,4,6-tri-t-butylphenol, butylhydroxyanisole, 1-hydroxy-3-methyl-4-isopropylbenzene, mono-t-butyl-p-cresol, mono-t-butyl-m-cresol, 2 , 4-Dimethyl-6-t-butylphenol, Butylated bisphenol A, 2,2'-methylene-bis- (4-methyl-6-t-butylphenol), 2,2'-methylene-bis- (4-ethyl -6-t-butylphenol), 2,2'-methylene-bis (4-methyl-6-t-nonylphenol), 2,2'-isobutylidene-bis (4,6-dimethylphenol), 4,4'-butylidene-bis- (3-methyl-6-t-butylphenol), 4,4'-methylene-bis- (2,6-di-t-butylphenol) 2,2-thio-bis- (4-methyl-6-tert-butylphenol), 4,4′-thio-bis- (3-methyl-6-tert-butylphenol), 4,4′-thio-bis -(2-Methyl-6-butylphenol), 4,4'-thio-bis- (6-tert-butyl-3-methylphenol), bis (3-methyl-4-hydroxy-5-tert-butylbenzene) Sulfide, 2,2-thio [diethyl-bis-3- (3,5-di-t-butyl-4-hydroxyphenol) propionate], bis [3,3-bis (4'-hydroxy-3'-t -Butylphenol) Butyric acid Glycol ester, bis [2- (2-hydroxy-5-methyl-3-t-butylbenzene) -4-methyl-6-t-butylphenyl] terephthalate, 1,3,5-tris (3 ′, 5 ′ -Di-t-butyl-4'-hydroxybenzyl) isocyanurate, N-octadecyl-3- (4'-hydroxy-3 ', 5'-di-t-butylphenol) propionate, tetrakis [methylene- (3', 5′-di-t-butyl-4-hydroxyphenyl) propionate] methane, 1,1′-bis (4-hydroxyphenyl) cyclohexane, mono (α-methylbenzene) phenol, di (α-methylbenzyl) phenol, Tri (α-methylbenzyl) phenol, bis (2′-hydroxy-3′-t-butyl-5′-methylbenzyl) 4-methyl-phenol, 2 , 5-di-t-amylhydroquinone, 2,6-di-butyl-α-dimethylamino-p-cresol, 2,5-di-t-butylhydroquinone, 3,5-di-t-butyl-4- Diethyl ester of hydroxybenzyl phosphate, 3,9-bis [2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2, 4,8,10-tetraoxaspiro [5.5] undecane.

The content of the antioxidant can further suppress the adhesion of oxygen, moisture, residual monomers and the like to the particles (A), particularly QD, and can more effectively suppress the generation of free radicals. ) Is preferably 1 to 100 parts by weight, more preferably 5 to 40 parts by weight with respect to 100 parts by weight of the particles (A).

[Polymerization initiator, acid generator and base generator]
The polymerization initiator, acid generator, and base generator are not particularly limited, and for example, compounds described in JP-A-2016-130809 can be used.

[Viscosity modifier]
The viscosity modifier is not particularly limited, and examples thereof include various thickeners and leveling agents in order to adjust the viscosity according to the molding method of the present composition. As the viscosity modifier, it is preferable to use a low-polarity compound for the purpose of blocking oxygen and water.

<This composition>
The method for preparing the composition is not particularly limited. For example, the composition may be prepared by mixing the particles (A), the particles (B), the solvent (C), and, if necessary, the binder and other components. Can be prepared.

The viscosity (25 ° C.) of the present composition may be appropriately selected depending on the desired application, application method, etc. For example, when the present composition is ink-jet printed, it is preferably about 1 to 20 mPa · s. When screen-printing the composition, it is preferably about 100 to 5000 mPa · s.
This composition having such a viscosity can be obtained by appropriately adjusting the amount of the solvent (C) used or by adding a viscosity modifier.

This composition is a device that efficiently converts the wavelength of light from a light source, for example, a light emitting layer of a light emitting display element that displays an image using visible light, a color tone adjusting layer of LED or fluorescent lamp illumination, and a light guide. It can be suitably used as a composition for forming a layer, a light receiving conversion layer of a photovoltaic power generation panel, and the like.
Specifically, a film or a molded body is formed from the present composition by a conventionally known method, in particular, a film is formed and used for these applications.

≪Wavelength conversion layer≫
The wavelength conversion layer (hereinafter also referred to as “main layer”) according to an embodiment of the present invention is:
A layer formed using the present composition (hereinafter also referred to as “layer 1”), or
A layer containing the phosphor particles (A) and the light diffusing material (B ′) and having a moisture absorption of 0.01 to 3% (hereinafter also referred to as “layer 2”).
Such a main layer has a low moisture absorption and a high luminous efficiency. In particular, since the moisture absorption amount of the layer itself is low, the characteristics of the phosphor particles (A), in particular, the light emission efficiency and the like are hardly lowered, and the layer changes when the wavelength conversion layer is used or when the layer is used in a device. It also has an effect that peeling from the layer is difficult to occur.
Furthermore, when quantum dots (hereinafter also referred to as “QD”) are used as the phosphor particles (A), since the QD is an expensive material, it is desired to suppress the use amount as much as possible, but to secure a light emission amount. Two trade-off requirements can be achieved simultaneously.

<Light diffusing material (B ')>
The light diffusing material (B ′) is not particularly limited as long as it is a material capable of diffusing light, and a conventionally known material can be used, but particles capable of diffusing light are preferable. One reason why the layer 2 exhibits the effect is the same as the reason why the composition described above exhibits the effect.
The light diffusing material (B ′) contained in the layer 2 may be one type or two or more types.

Examples of the light diffusing material (B ′) include particles and voids (eg, bubbles). The particles may be solid particles, but are preferably the hollow particles (B) having pores therein.
By using the hollow particles (B) as the light diffusing material (B ′), the amount of light incident on the particles (A) can be increased, and the emitted light from the particles (A) can be efficiently diffused. The wavelength conversion layer having high luminous efficiency can be easily obtained, and even if the thickness of the layer 2 is reduced or the amount of the particles (A) in the layer 2 is reduced, the particles ( The amount of light emitted can be ensured by the increase in the amount of light incident on A).
Furthermore, by using the hollow particles (B) as the light diffusing material (B ′), a wavelength conversion layer having excellent bending resistance can be easily obtained.
Examples of the hollow particles include particles similar to the particles described in the column of the present composition.

The content of the light diffusing material (B ′) in this layer has a low moisture absorption, a high luminous efficiency, and a wavelength conversion layer that can maintain the luminous efficiency over a long period of time can be easily obtained. From this point, it is preferably 0.1 to 50% by mass, more preferably 0.3 to 30% by mass, and further preferably 0.5 to 25% by mass.

In this layer, in addition to the particles (A) and the light diffusing material (B ′), one or more of the binders or cured products thereof, one or more of the compositions described in the column of the present composition Other components may be included.
When this layer contains a binder (C), the binder (C) content is low in moisture absorption, has high luminous efficiency, and easily forms a wavelength conversion layer having a desired (surface) shape. In view of the transmittance of the obtained wavelength conversion layer, it is preferably 50 to 95% by mass, more preferably 60 to 90% by mass with respect to 100% by mass of the main layer.

<Method for producing wavelength conversion layer>
This layer is not particularly limited and can be produced by a conventionally known method. However, the layer (hereinafter referred to as “component (B′1) which becomes the light diffusing material (B ′) in the particles (A) and the obtained layer). The method including a step of forming a layer using a composition containing the composition (hereinafter also referred to as “composition C”) is preferable, and a method including the step of forming a layer using the present composition. Is more preferable.
The composition C may be a composition containing the particles (A) and the component (B′1). For example, the composition C may contain the composition containing the particles (A) and the component (B′1). Two or more types of compositions, such as a composition containing, may be sufficient.
When two or more kinds of compositions are used, the finally obtained layer may be a layer containing the particles (A) and the light diffusing material (B ′).

The composition C includes the particles (A) and / or the component (B′1), and if necessary, the binder component, the other components, and the like. Conventionally known arbitrary components may be included within a range not impairing the effects of the present invention.
Examples of the optional component include an organic solvent, a polymerization initiator, an acid generator, a base generator, and a viscosity modifier.
Each of the optional components may be used alone or in combination of two or more.

[Ingredient (B′1)]
The component (B′1) may be the particle (B), and the composition and the like change at the stage of forming the wavelength conversion layer, and the changed component has a light diffusing ability. It may be a component. Examples of the latter include foaming agents such as p, p′-oxybisbenzenesulfonylhydrazide, sodium hydrogen carbonate, dinitrosopentamethylenetetramine, azodicarbonamide, and inorganic foaming agent P-5 (manufactured by Otsuka Chemical Co., Ltd.). Is mentioned.

The method for forming a layer using the composition is not particularly limited, and includes a step 1 for applying the composition on a substrate to form a coating film and a step 2 for curing the obtained coating film. A method comprising is preferred.

The substrate is not particularly limited, and a conventionally known substrate made of metal, resin, or glass can be used, and the member itself on which the phosphor particle-containing film is to be formed may be used as the substrate.
The base material may be subjected to a surface treatment.

The coating method is not particularly limited, and a conventionally known method can be appropriately selected according to a desired application. For example, spin coating method, slit coating method, dipping method, gravure printing, inkjet printing, screen printing. And a nozzle printing method. Among these, the ink-jet ink can be more easily obtained from the point that it is possible to more easily obtain the light-diffusing effect by the light-diffusing material (B ′) and the fluorescent light-emitting effect by the particles (A). Printing is preferred.

In addition, when apply | coating this composition to a base material, you may apply | coat to the film form which covers a part of surface of this base material, or may apply | coat so that it may become a projection on a flat base material. Alternatively, it may be applied so as to be embedded in a concave portion of a base material formed in advance.

The step 2 is not particularly limited as long as the coating film is cured, and the conditions may be appropriately adjusted depending on the composition to be used. However, when the photocurable component is used as the binder component, a heating step is performed. Next, a method of performing a light irradiation step is preferable.

The heating may be one-stage heating or two-stage heating or more.
As such heating conditions, the heating temperature is preferably 60 ° C. or higher, more preferably 80 ° C. or higher, and the upper limit is preferably 200 ° C. in consideration of the heat resistance of the substrate. Moreover, when using a foaming agent as a component used as a light-diffusion material (B ') in the layer obtained, it is preferable to heat at the temperature more than the temperature which this foaming agent foams.

The light irradiation conditions are not particularly limited, and examples include conditions in which ultraviolet rays are used as exposure light and the exposure amount is 0.05 to 5 J / cm ² .

Further, when an alkali-soluble component or the like is used as the binder, a film having a desired shape can be obtained by performing pattern exposure and subsequent development step before or after the step 2.

The obtained wavelength conversion layer may be used after being peeled from the base material, or may be used without being peeled from the base material when the member itself on which the wavelength conversion layer is to be formed is used as the base material.

<Physical properties of wavelength conversion layer>
This layer is characterized in that the characteristics of the particles (A), in particular, luminous efficiency and the like are hardly deteriorated, dimensional change is difficult to occur, the luminous efficiency is high, and a layer having excellent long-term stability can be easily obtained. The moisture absorption is preferably 0.01 to 3%, more preferably 0.01 to 2%, and particularly preferably 0.01 to 1%.
The moisture absorption can be specifically measured by the method described in the following examples.
Such a wavelength conversion layer having a moisture absorption amount can be obtained by adjusting the type and amount of the light diffusing material (B ′), the amount of the binder (C), and the like.

The wavelength conversion layer may be required to have bending resistance, and a wavelength conversion layer having excellent bending resistance is required.
Specifically, in the bending resistance test by the cylindrical mandrel method based on JIS-K5600-5: 1-1: 1999, there is a relationship between the diameter (mm) of the mandrel where the crack occurs and the thickness (μm) of the wavelength conversion layer. It is preferable to satisfy the following requirements (i) or (ii).
Requirement (i): When the thickness of the wavelength conversion layer is 11.8 μm or more, the diameter of the mandrel (mm) where the crack that satisfies the following formula is satisfied / the thickness of the wavelength conversion layer (μm) ≦ 0.17 is satisfied.
Requirement (ii): When the thickness of the wavelength conversion layer is less than 11.8 μm, no crack is generated in the wavelength conversion layer even when a mandrel having a diameter of 2 mm is used. The right side of the expression of the requirement (i) is preferably 0. .14, more preferably 0.1.
The wavelength conversion layer having such bending resistance uses hollow particles as the light diffusion material (B ′), the amount of the light diffusion material (B ′) in the wavelength conversion layer, the amount of the binder (C), It can be obtained by adjusting the porosity of the layer.

This layer is a layer that converts the wavelength of light incident from the light source, and the wavelength of the light after conversion may be appropriately selected depending on the desired application. Usually, the wavelength is in the range of 520 to 560 nm and the wavelength is 600 to 600. Often includes light in the 700 nm range. Therefore, this layer preferably has a high light transmittance in these wavelength regions.
Specifically, in the wavelength range of 520 to 560 nm and the wavelength range of 600 to 700 nm, the average value of the respective transmittances when measured from the vertical direction of the wavelength conversion layer is preferably 70% or more. More preferably, it is 75% or more, More preferably, it is 80% or more.
In particular, when this layer is used in a visible light display device, it is preferable that the transmittance is satisfied.

This layer (thickness 3 μm) preferably has a haze (average haze) measured by the method described in the following examples of 1 to 80%, more preferably 3 to 60%.
Since the haze is an index of the light scattering degree, when the haze is in the above range, the light use efficiency increases due to the effect of light diffusion, so that a film with high light emission efficiency can be easily obtained.

This layer has a standard deviation of haze measured by the method described in the following examples, preferably 5% or less, more preferably 3% or less, and still more preferably 1% or less.
Since the standard deviation of the haze is an index representing the uniformity of the coating film surface, a film having uniform light emission characteristics without unevenness can be obtained when the standard deviation is within the above range.

This layer has a porosity of preferably 1 to 50 vol% observed in a cross section when the layer is cut from the viewpoint that the layer is excellent in balance due to luminous efficiency, bending resistance, light transmission, and the like. More preferably, it is 5 to 50 vol%, and further preferably 10 to 40 vol%.
The porosity can be specifically measured by the method described in the following examples.

The thickness of this layer may be appropriately selected according to the desired application, but is usually 0.5 to 200 μm, and is more preferable from the viewpoint that it can be suitably used for a device that is required to be light and thin. Is 1 to 100 μm.

<Application of wavelength conversion layer>
This layer is a device that efficiently converts the wavelength of light from a light source, for example, a light emitting layer of a light emitting display element that displays an image using visible light, a color tone adjusting layer and a light guiding layer of LED or fluorescent lamp illumination. It can be suitably used as a light receiving conversion layer of a photovoltaic power generation panel.

The place where this layer is formed is not particularly limited and may be appropriately selected according to the desired application. For example, in a display device using a liquid crystal shutter or an optical switch using a light emitting element, the optical switch Examples thereof include an element substrate, a light guide member in the device (out-cell structure), a display screen member in a projection display device, a photoelectric conversion element, a photovoltaic power generation panel, and a light guide member constituting a lighting fixture. .

Hereinafter, the present invention will be described in detail based on specific examples, but the present invention is not limited to these specific examples.

[Synthesis Example 1] Synthesis of phosphor a1 (quantum dot) Synthesis was performed according to Chem. Mater., 2015, 27 (13), pp 4893-4898. Specifically, the synthesis was performed by the following method.
In a four-necked flask with a stirrer attached to a vacuum line and a connecting line to a nitrogen line, a thermocouple thermometer, a reflux pipe and a septum in four necks, indium chloride 8.44 g, zinc chloride 5.2 g and After mixing 163.3 g of oleylamine, the resulting mixture was heated at 110 ° C. for 1 hour while removing water and oxygen under vacuum conditions, returned to normal pressure with nitrogen, and the contents were heated to 190 ° C.

15.7 g of trisdiethylaminophosphine was injected into the liquid mixture at 190 ° C. to start the reaction, and the mixture was stirred and reacted at 185 ° C. for 20 minutes. The resulting solution was heated to 200 ° C., and 15.4 g of a trioctylphosphine sulfur adduct (a compound in which equimolar trioctylphosphine and sulfur were mixed and dissolved uniformly) was added and reacted for 2 hours. Next, 82.6 g of zinc stearate and 330 g of octadecene were added, the temperature was raised to 220 ° C., and the mixture was reacted for 30 minutes, and then 52.6 g of a sulfur addition product of trioctylphosphine was added. After raising the temperature of the reaction solution to 240 ° C. and reacting for 30 minutes, 41 g of zinc stearate and 165 g of octadecene were added and reacted at 260 ° C. for 30 minutes. The reaction solution was cooled to room temperature under a nitrogen stream to synthesize an InP / ZnS core-shell nanocrystal crude product.

The flask containing the obtained reaction solution was transferred into a glove box, and the content solution was transferred to a beaker. Toluene was added to the beaker, ethanol was added to settle the particles, and then centrifugation was performed. The obtained particles were redispersed in toluene, and the operation of adding ethanol and centrifuging was repeated 5 times, and then toluene was added to the obtained particles and redispersed so that the inorganic component content was 3% by mass. To obtain a phosphor a1 dispersion. In addition, solid content concentration after carrying out the heat drying (90 degreeC, 20 minutes) of fluorescent substance a1 dispersion liquid was 7.5 mass%, and the organic content was included in addition to the inorganic component.

Using the obtained phosphor a1 dispersion, Quantaurus-QY (manufactured by Hamamatsu Photonics Co., Ltd.) was used, and the fluorescence spectrum was measured using light having a wavelength of 450 nm as excitation light. The wavelength at the peak top (maximum fluorescence wavelength) of the obtained spectrum was 648 nm, and the half-width of the peak (width at the half height of the peak) was 50 nm.

Further, the particle diameter of the phosphor a1 was measured with a transmission electron microscope (“JEM-2010F”, manufactured by JEOL Ltd.). When the average particle diameter was determined by averaging the outer diameters of any 20 particles in the observation field, it was 4.5 nm.

Using a thermal mass (TGA) analyzer (Thermo PLUS PLUS EVO2, manufactured by Rigaku Corporation), TGA analysis was performed at a heating rate of 5 ° C./min under an air flow. The inorganic content in the phosphor a1 was 40% by mass. there were. That is, the InP / ZnS core-shell nanocrystal functioning as a phosphor was 40% by mass, and the remaining 60% by mass was an organic component (ligand component) that dispersed and stabilized the quantum dots.

Production of Phosphor a2 Dispersion Using a propylene glycol monomethyl ether acetate (PGMEA) dispersion of RE-316 (manufactured by Denka Co., Ltd., inorganic fluorescent particles), and a bead mill (rotation speed: 1500 rpm) using zirconia beads The phosphor a2 dispersion (solid content concentration: 7.5% by mass) was obtained by pulverizing so that the average particle size of RE-316 in the dispersion was 200 nm.
The average particle diameter was measured by a dynamic light scattering method using a nanoparticle analyzer “Delsa Nano S” manufactured by Beckman Coulter.

[Phosphor a3]
Fluorescent substance a3 is obtained by dry-pulverizing Aronbright GR-MW540H manufactured by Denka Co., Ltd. using dry bead mill Sigma Dry SDA5 (manufactured by Ashizawa Finetech Co., Ltd.) until the average particle size becomes 300 nm. It was.
The maximum fluorescence wavelength was measured in the same manner as described above using a dispersion liquid (solid content concentration: 7.5 mass%) in which the phosphor a3 was dispersed in toluene, and it was 544 nm.

[Production Example 1] Production of hollow particles b1 In a reaction vessel having a capacity of 2 liters, 109.5 parts by weight of water as a medium and 0.2 parts by weight of sodium dodecylbenzenesulfonate (F65, manufactured by Kao Corporation) as an emulsifier As a polymerization initiator, 0.5 part by mass of sodium persulfate was added.

Meanwhile, 90 parts by mass of methyl methacrylate, 10 parts by mass of methacrylic acid, 2.5 parts by mass of octylthioglycol as a molecular weight regulator, 0.1 part by mass of an emulsifier (F65, manufactured by Kao Corporation) and 40 parts by mass of water are mixed. An aqueous dispersion 1 of the monomer mixture was prepared by stirring.

20% by mass of the obtained aqueous dispersion 1 of the monomer mixture was put into the reaction vessel, and the temperature was raised to 75 ° C. while stirring the liquid in the reaction vessel to conduct a polymerization reaction for 1 hour. While maintaining the temperature at 75 ° C., the remaining 80 mass% of the aqueous dispersion 1 of the monomer mixture was continuously added to the reaction vessel over 2 hours. Furthermore, the seed particle aqueous dispersion (solid content: 40% by mass) was obtained by aging for 2 hours.

Next, 79.5 parts by weight of methyl methacrylate, 20 parts by weight of methacrylic acid, 0.5 parts by weight of divinylbenzene (purity 81%), 3 parts by weight of octylthioglycol, emulsifier (F65, manufactured by Kao Corporation) 0.1 An aqueous dispersion 2 of a monomer mixture was prepared by mixing and stirring parts by mass and 40 parts by mass of water.

On the other hand, 186 parts by mass of water as a medium was previously charged into a reaction vessel having a capacity of 2 liters, and 25 parts by mass of the obtained aqueous dispersion of seed particles was added to the reaction container. 5 parts by mass were added. While stirring the liquid in the reaction vessel, the temperature was raised to 80 ° C., and while maintaining this temperature, the obtained aqueous dispersion 2 of the monomer mixture was continuously added over 3 hours. Thereafter, aging was further performed for 2 hours to obtain an aqueous dispersion of the first polymer particles having a particle diameter of 0.41 μm (solid content: 31% by mass).

Next, 56.5 parts by mass of styrene, 3 parts by mass of ethylene glycol dimethacrylate, 0.1 part by mass of an emulsifier (F65, manufactured by Kao Corporation) and 40 parts by mass of water were mixed and stirred to obtain a polymerizable monomer (β) mixture. Aqueous dispersion 3 was prepared.

On the other hand, 240 parts by mass of water was previously charged as a medium in a reaction vessel having a capacity of 2 liters, and 48.4 parts by mass of the obtained aqueous dispersion of the first polymer particles, 20 parts by mass of styrene, and As a polymerization initiator, 0.4 part by mass of sodium persulfate was added. While stirring the liquid in the reaction vessel, the temperature was raised to 80 ° C., and styrene was polymerized at this temperature for 30 minutes to obtain polymer particles in which a polymer of styrene was combined with the first polymer particles.
The liquid in the obtained reaction vessel was kept at 80 ° C. with stirring, and the aqueous dispersion 3 of the polymerizable monomer (β) mixture was continuously added thereto over 4 hours. At this time, 0.5 part by mass of acrylic acid was charged all at once into the reaction vessel and copolymerized with styrene at the elapse of 2 hours after the start of the addition of the aqueous dispersion 3. After all of the aqueous dispersion 3 has been charged into the reaction vessel, 20 parts by mass of divinylbenzene (purity 81%) are charged all at once, and styrene, acrylic acid, ethylene glycol dimethacrylate, divinylbenzene are applied to the surface layer of the first polymer particles. As a result, core-shell particles were laminated. In addition, the unreacted polymerizable monomer (β) was present in the obtained core-shell particles.

Approximately 15 minutes after the completion of the addition of the aqueous dispersion 3, 5 parts by mass of a 20% aqueous ammonia solution was added all at once to the reaction vessel while stirring, the temperature was raised to 90 ° C., and the mixture was aged and stirred for 2 hours. Thereafter, 0.3 part by mass of t-butyl hydroperoxide and 0.1 part by mass of formaldehyde resin were added, and the mixture was allowed to stand for 1 hour as it was, whereby an aqueous dispersion of spherical hollow particles b1 having single pores. Em1 (solid content 26.5% by mass) was obtained.

The obtained aqueous dispersion of hollow particles b1 is centrifuged at 15000 rpm for 30 minutes using a centrifuge to obtain a precipitate of hollow particles, and this precipitate is obtained at 25 ° C. for 24 hours using a vacuum dryer. The hollow particles b1 were obtained by drying.

[Production Example 2] Production of hollow particles b2 In Production Example 1, the amount of sodium dodecylbenzenesulfonate used in each stage of the reaction was increased to twice the amount of Production Example 1 in the same manner as in Production Example 1. Hollow particles b2 were obtained.

[Production Example 3] Production of hollow particles b3 In Production Example 1, except that the amount of divinylbenzene (purity 81%) charged after all of the aqueous dispersion 3 was charged into the reaction vessel was changed to 18 parts by mass. In the same manner as in Production Example 1, hollow particles b3 were obtained.

<Hollow particle size>
Hollow particles were embedded in an epoxy resin (Cosmo Bio Co., Ltd., using Quetol 651 Kit), and after curing the epoxy resin, ultrathin sections were cut out with a microtome, and JEM-1400Plus (manufactured by JEOL Ltd.) ) Were used for TEM observation. Twenty particles in the observation field are arbitrarily selected, the maximum diameter of the pores of these particles and the maximum diameter of the outer shell constituting the hollow particles are measured, and the inner diameter and the outer diameter are respectively calculated from the average value of 20 particles. Was calculated.
Further, assuming that the particle shape is a true sphere, the shell thickness (average film thickness) was calculated from the outer diameter and inner diameter data, and the shell thickness / outer diameter (shell / outer diameter) was calculated. Furthermore, the void volume was calculated from the inner diameter, the particle volume was calculated from the outer diameter, and the porosity was determined from the ratio.
The particle diameter variation coefficient (CV) was calculated from the outer diameter measurement data of 20 particles based on the formula CV = (standard deviation / outer diameter).
These results are shown in Table 1.

<Toluene insoluble matter>
About 1 g of hollow particles are collected and weighed accurately (w1 g), the particles are immersed in 100 mL of toluene, stirred at 80 ° C. for 6 hours, and then centrifuged at 15000 rpm for 30 minutes using a centrifuge. A part (vmL) was evaporated to dryness and solidified, and the obtained residual solid content (toluene soluble content w2 g) was weighed, and the toluene insoluble content was calculated by the following formula (1). The results are shown in Table 1.
Toluene insoluble matter (mass%) = (w1− (w2 × 100 / v)) / w1 × 100 (1)

<Heat-resistant temperature>
Using a differential thermal balance Thermo plus EVO2 (manufactured by Rigaku Corporation), the hollow particles were heated from 40 ° C. to 500 ° C. under a temperature increase rate of 5 ° C./min under an air flow of 200 cc / min. The temperature at which 5% mass changed from the mass before the start of temperature increase was defined as the heat resistant temperature. The results are shown in Table 1.

[Example 1]
In a container, 933 parts by mass of the phosphor a1 dispersion was weighed, and particles b1 (100 parts by mass) and mesitylene (10149 parts by mass) were added and mixed, and then dipentaerythritol hexaacrylate (382 parts by mass) and Irgacure 184 (20 parts by mass) was added, ultrasonically irradiated for 30 minutes, dispersed and mixed, and coarse solids were removed with a 1 μm filter to obtain a phosphor particle-containing composition.

[Examples 2 to 10 and Comparative Example 1]
A phosphor particle-containing composition was obtained in the same manner as in Example 1 except that the components shown in Table 2 were used in the amounts shown in Table 2. In addition, the numerical value in the bracket | parenthesis described in the lower stage of the kind of each component in Table 2 is the usage-amount (mass part) of each component.

Abbreviations of each component in Table 2 are as follows.
"DPHA": Dipentaerythritol hexaacrylate "MOSA": 2-methacryloyloxyethyl succinic acid "Polymer D": polymer obtained in the following Production Example 4 "Irg184": Irgacure 184 (manufactured by BASF, light Polymerization initiator)
"AO-80": ADK STAB AO-80 (manufactured by ADEKA, phenolic antioxidant)
"AO-412S": ADK STAB AO-412S (manufactured by ADEKA, thioether antioxidant)
"TTO": TTO-51 (C) (Ishihara Sangyo Co., Ltd., ultrafine titanium oxide)

[Production Example 4] Production of polymer D A flask equipped with a cooling pipe and a stirrer was charged with 150 parts by mass of PGMEA and purged with nitrogen. Heated to 80 ° C., at the same temperature, 50 parts by weight of PGMEA, 10 parts by weight of methacrylic acid, 30 parts by weight of cyclohexyl methacrylate, 10 parts by weight of styrene, 20 parts by weight of mono (2-methacryloyloxyethyl) succinate, methacrylic acid A mixed solution of 3 parts by weight of 2-hydroxyethyl, 15 parts by weight of 2-ethylhexyl methacrylate, 12 parts by weight of N-phenylmaleimide and 6 parts by weight of 2,2′-azobis (2,4-dimethylvaleronitrile) is taken over 2 hours. The mixture was added dropwise and polymerized for 1 hour while maintaining this temperature. Thereafter, the temperature of the reaction solution was raised to 90 ° C., and further polymerized for 1 hour to obtain a PGMEA solution of polymer D (solid content concentration: 33 mass%). The obtained polymer D had Mw of 10,800, Mn of 5,900, and Mw / Mn of 1.83.

[Mw, Mn and Mw / Mn]
Mw and Mn were measured by gel permeation chromatography (GPC) under the following conditions to calculate Mw / Mn.
Equipment: “GPC-101” manufactured by Showa Denko K.K.
Column: “GPC-KF-801”, “GPC-KF-802”, “GPC-KF-803” and “GPC-KF-804”, manufactured by Showa Denko KK Mobile phase: Tetrahydrofuran Column temperature : 40 ° C
Flow rate: 1.0 mL / min Sample concentration: 1.0% by mass
Sample injection volume: 100 μL
Detector: Differential refractometer Standard material: Monodisperse polystyrene

<Luminous efficiency>
The compositions obtained in Examples and Comparative Examples were coated on a 0.7 mm thick, 150 mm × 180 mm glass substrate so that the resulting coating film thickness was 3 μm.
The following three types of coating films were each cut into a size of 1 cm × 1 cm, and luminescence characteristics were measured at an excitation light wavelength of 450 nm using Quantaurus-QY (manufactured by Hamamatsu Photonics Co., Ltd.) to evaluate luminous efficiency.

Luminous efficiency is the coating film when the coating film is formed on the glass substrate (during film formation), the coating film is heated on a hot plate at 180 ° C. for 10 minutes and cooled for 5 minutes (after heating) And the coating film at the time of film-forming was measured using each of the coating film (after immersion) after being immersed in toluene for 1 hour and then immersed in water for 1 hour and then dried at 90 ° C. for 5 minutes.
Table 2 shows the results of the luminous efficiency when the luminous efficiency of the coating film (during film formation) obtained using the composition of Comparative Example 1 is taken as 100.

This composition can be used by forming a wavelength conversion layer such as an LED from the composition. Layers other than the wavelength conversion layer are also laminated on the LED and the like, and in that case, usually a heating or dipping process is included. Accordingly, since it is desired that the film (phosphor particle-containing film) obtained from the present composition does not change in properties even after such heating and immersion processes, as described above, after heating and after immersion. The luminous efficiency of the film was also measured.

<Haze>
Haze was measured with a haze meter HM-150 (manufactured by Murakami Color Research Laboratory Co., Ltd.) using a coating film (during film formation) prepared for measuring luminous efficiency. The measurement was performed at 20 arbitrary locations on a 150 mm × 180 mm glass substrate, and an average value and a standard deviation were calculated from the obtained haze values.
The haze value was determined according to JIS K7136 and used as an index of light scattering degree. The standard deviation was an index representing the uniformity of the coating surface. When the standard deviation was 2% or less, it was judged that the coating film had no unevenness and was a good coating film.

The composition obtained in the example could form a film showing high luminous efficiency.
When the composition obtained in Example 1 was used, no unevenness was visually observed and a good coating film could be formed. When haze evaluation of the coating film was performed, the average haze value was 50%, and the haze value was The standard deviation was 1%. This is presumably because the CV value of the particle b1 is small and the uniformity of film formation is good.

[Preparation Examples 1 to 9 and 12 to 14]
The three rolls (BR-100V, manufactured by IMEX Co., Ltd.), which is a mixing device, are kneaded in this order with component (B′1), binder component, phosphor particles and additives in the mixing ratio shown in Table 3. Then, a photosensitizer was added at the end and kneaded and dispersed for 30 minutes until a uniform paste was obtained, to obtain a composition.

[Preparation Examples 10 to 11]
The phosphor particles, component (B′1) and organic solvent (butyl acetate or mesitylene) among the additives were mixed according to the mixing ratio in Table 3 and then dispersed by ultrasonic irradiation for 30 minutes. A binder component, other additives and a photosensitizer were added according to the mixing ratio shown in Table 3, and after stirring and mixing, a coarse solid was removed with a 1 μm filter to obtain a composition.

In addition, the numerical value of the lower stage in Table 3 represents the mixing ratio (mass part) of the solid content in each component, and in Table 3, the numerical value described under the phosphor a1 dispersion is the mass of the phosphor a1. This shows that the dispersion was used.

Abbreviations of each component in Table 3 other than the abbreviations described in Table 2 are as follows.
“Solid particles 1”: silica particles (Seahoster KE-S50, manufactured by Nippon Shokubai Co., Ltd., outer diameter: 0.5 μm, porosity: 0%)
"AP": Pentaerythritol tri (meth) acrylate "UV ink UV1": Hard UV ink SPC-0371 (Mimaki Engineering Co., Ltd.)
・ "UV ink UV2": UV IJ-LED series LOW type (manufactured by T & K TOKA)

[Preparation of aqueous composition]
[Preparation Examples 15 to 16]
According to the mixing ratio of Table 4, each aqueous dispersion was added and mixed in the order of aqueous dispersion Em1, binder component and cross-linking agent, and water was added to adjust the concentration so that the solid content was 30%. The product was removed by filtration with a 400 mesh SUS net to obtain an aqueous composition.

Abbreviations for each component in Table 4 are as follows.
"Aqueous dispersion Em2": Chemite Z-33 (manufactured by Nippon Shokubai Co., Ltd.)
・ "Aqueous dispersion Em3": Carbodilite E-02 (Nisshinbo Chemical Co., Ltd.)
"Aqueous dispersion Em4": Acrylic urethane emulsion WEM-3000 (manufactured by Taisei Fine Chemical Co., Ltd.)
"Aqueous dispersion Em5": Acrylic emulsion AE173A (manufactured by Etec Co., Ltd.)

In addition, the numerical value of the lower stage in Table 4 represents the mixing ratio (mass part) of the solid content in each component.

[Examples 11 to 19, Examples 22 to 23, and Comparative Examples 2 to 4]
Using the composition shown in Table 5, according to each film-forming method shown in Table 5, the thickness of the layer obtained on the PET film substrate (Teijin Tetron Film G2, Teijin DuPont Films Co., Ltd., 100 μm thickness) The wavelength conversion layer was formed so as to have the thickness shown in FIG.
When the wavelength conversion layer obtained in the Example was visually confirmed, the film formation state was good, and the light emission efficiency exceeded 100, and an efficient wavelength conversion layer was confirmed.

[Example 20]
1 mm surrounded by a polyimide film (made by Toray DuPont, Kapton 200H / V, thickness: 50 μm) with a polyimide tape (polyimide adhesive tape for heat-resistant insulation No. 360A, manufactured by Nitto Denko Corporation, thickness: 50 μm) A substrate having corner sections and a recess having a depth of 50 μm was prepared.
After applying the aqueous composition of Preparation Example 15 to this recess using an inkjet apparatus (DotView), the obtained substrate was heated at 90 ° C. for 5 minutes, and then heated to 230 ° C. over 5 minutes. And calcination at 230 ° C. for 5 minutes. A cured film having a thickness of 40 μm was formed in the recess.
On the layer obtained using the aqueous composition of Preparation Example 15, a layer was formed by the following Method 4 using Preparation Example 12.
By removing the polyimide tape, a wavelength conversion layer having a size of 1 mm square and a height of 50 μm was obtained.

[Example 21]
A wavelength conversion layer was formed in the same manner as in Example 20 except that the aqueous composition of Preparation Example 16 was used instead of the aqueous composition of Preparation Example 15.

<Method for forming wavelength conversion layer>
"Method 1" screen printing Using a screen printing machine (HP-320 type screen printing machine, manufactured by Neurong Seimitsu Kogyo Co., Ltd.), the composition is printed on the substrate in a pattern of 5 mm square, 90 ° C After drying in an oven for 20 minutes, the pattern was cured by UV irradiation (UV conveyor QRM-2288, manufactured by Oak Manufacturing Co., Ltd., exposure amount: 0.5 J / cm ² ).

"Method 2" Nozzle printing Using a nozzle printing device (NP-750G, manufactured by Screen), the composition was applied onto the substrate so as to be 5 mm square, and dried in an oven at 90 ° C for 20 minutes. The composition was cured by UV irradiation (UV conveyor QRM-2288, exposure amount: 0.5 J / cm ² ).

"Method 3" Slit coat Using a slit coater (LC-R300G, manufactured by Screen), the composition was coated on the entire surface, dried in an oven at 90 ° C for 20 minutes, and then irradiated with UV (UV Conveyor QRM-2288, exposure amount: 0.5 J / cm ² ), the composition was cured.

“Method 4” Inkjet Inkjet apparatus (DotView) was used to apply the composition onto the substrate, and after drying in an oven at 90 ° C. for 20 minutes, UV irradiation (UV conveyor QRM-2288, exposure: 0. 5 J / cm ² ) to cure the composition.

<Moisture absorption>
From the wavelength conversion layer obtained in the examples and comparative examples, the PET film or the polyimide film was peeled off, and the obtained wavelength conversion layer was cut out to be about 1 g, and the obtained layer was heated at 120 ° C. with a hot air dryer. After drying for 12 hours, the mass (W1) of the layer was measured. Next, the layer after measuring the weight (W1) was allowed to stand in a constant temperature and humidity chamber adjusted to a temperature of 30 ° C. and a relative humidity of 90% RH for 12 hours, and then the mass (W2) of the layer was measured. The moisture absorption amount of the wavelength conversion layer was determined by the following formula. The results are shown in Table 5.
Moisture absorption (mass%) = [(W2-W1) / W1] × 100

<Mandrel bending test>
In accordance with JIS-K5600-5-1: 1999 (cylindrical mandrel method), using a test piece prepared with a wavelength conversion layer with a PET film or polyimide film having a size of 100 mm × 50 mm according to the above-mentioned examples and comparative examples. The test was performed with a type 1 test apparatus, and the bending resistance test of the wavelength conversion layer was performed.
The case where the white line was visually recognized in the wavelength conversion layer was evaluated as having cracked. Table 5 shows the diameter of the mandrel when the crack occurs.
In Table 5, “<2” indicates that no crack was generated even when a mandrel having a diameter of 2 mm was used.

<Transmissivity>
A wavelength conversion layer with a PET film or a polyimide film was prepared in a size of 30 mm square according to Examples and Comparative Examples, and each wavelength range of green wavelength (520 to 560 nm) and red wavelength (600 to 700 nm) was measured with a spectrophotometer. The transmittance was measured. In addition, the transmittance | permeability of the wavelength conversion layer was computed by correct | amending the light absorption part of the PET film or polyimide film used as the base material from the transmittance | permeability measured using the PET film or the wavelength conversion layer with a polyimide film. The results are shown in Table 5.

<Porosity>
The wavelength conversion layer with PET film or polyimide film obtained in Examples and Comparative Examples was embedded with an epoxy resin (Cosmo Bio Co., Ltd., using Quetol 651 Kit), and after curing the epoxy resin, with a microtome Ultrathin sections were cut out, and any 10 samples were observed with TEM using JEM-1400Plus (manufactured by JEOL Ltd.). Twenty voids in the observation field were arbitrarily selected, and the maximum diameter (gap size) of each of the 20 voids was measured. Table 5 shows the average of a total of 200 voids.
Further, the void ratio (vol%) in the wavelength conversion layer was calculated from the ratio of the total area of the voids in the observation visual field in each sample and the observation visual field area, assuming that the voids were true spheres. Table 5 shows the average porosity calculated for 10 samples.

<Luminous efficiency>
A wavelength conversion layer with a PET film or a polyimide film was prepared in a size of 1 cm × 1 cm according to the examples and comparative examples, and using Quantaaus-QY (manufactured by Hamamatsu Photonics Co., Ltd.), the luminous efficiency was obtained at an excitation light wavelength of 450 nm. Measured.
Table 5 shows the luminous efficiency in each test when the luminous efficiency of Comparative Example 2 is 100.

Claims

Including phosphor particles (A), hollow particles (B) and organic solvent (C),
The phosphor particles (A) contain In,
Phosphor particle-containing composition.
Including phosphor particles (A), hollow particles (B) and organic solvent (C),
The hollow particles (B) are organic hollow particles.
Phosphor particle-containing composition.
The phosphor particle-containing composition according to claim 1 or 2, wherein a content of toluene insoluble in the hollow particles (B) is 90 to 100% by mass.
The phosphor particle-containing composition according to any one of claims 1 to 3, comprising a bifunctional or higher functional (meth) acrylic acid ester.
The phosphor particle-containing composition according to any one of claims 1 to 4, comprising a binder resin.
6. The phosphor particle-containing composition according to claim 1, wherein an average film thickness of the shell of the hollow particles (B) is 0.005 to 0.1 μm.
The phosphor particles (A) are InP / ZnS compounds, InP / ZnSe compounds, InP / ZnSe / ZnS compounds, InP / (ZnS / ZnSe) solid solution compounds, InP / ZnSeS compounds, CuInS 2 / ZnS compounds, AgInS 2 compounds. The phosphor particle-containing composition according to claim 1, comprising at least one quantum dot selected from the group consisting of: (ZnS / AgInS 2 ) solid solution / ZnS compound and Zn-doped AgInS 2 compound. object.
The organic solvent (C) is 1,2-propylene glycol-1-methyl ether-2-acetate, 1,3-butanediol-1-acetate-3-methyl ether, 3-methoxybutanol, 1,2-propylene Glycol-1-methyl ether, 1,2-propylene glycol-1-ethyl ether, diethylene glycol monopropyl ether, di (1,3-propylene glycol) -1-monomethyl ether, cyclohexanone, 3-ethoxybutanol, 3-hydroxypropion At least selected from the group consisting of acid-1-ethyl ester-3-ethyl ether, 3-hydroxypropionic acid-1-methyl ether-1-methyl ester, diethylene glycol dimethyl ether and diethylene glycol methyl ethyl ether It is one, the phosphor particle-containing composition according to any one of claims 1 to 7.
A wavelength conversion layer formed using the phosphor particle-containing composition according to any one of claims 1 to 8.
The wavelength conversion layer according to claim 9, wherein the moisture absorption is 0.01 to 3%.
A wavelength conversion layer containing phosphor particles (A) and a light diffusing material (B ′) and having a moisture absorption of 0.01 to 3%.
In the bending resistance test by the cylindrical mandrel method according to JIS-K5600-5-1: 1999, the relationship between the diameter (mm) of the mandrel where the crack occurs and the thickness (μm) of the wavelength conversion layer is the following requirement (i The wavelength conversion layer according to any one of claims 9 to 11, which satisfies (ii) or (ii).
Requirement (i): When the thickness of the wavelength conversion layer is 11.8 μm or more, the diameter of the mandrel (mm) where the crack that satisfies the following formula is satisfied / the thickness of the wavelength conversion layer (μm) ≦ 0.17 is satisfied.
Requirement (ii): When the thickness of the wavelength conversion layer is less than 11.8 μm, no crack occurs in the wavelength conversion layer even when a mandrel having a diameter of 2 mm is used.
The average value of the respective transmittances when measured from the vertical direction of the wavelength conversion layer in the wavelength range of 520 to 560 nm and the wavelength range of 600 to 700 nm are both 70% or more. 2. The wavelength conversion layer according to item 1.
A step of forming a layer using the phosphor particles (A) and a component that becomes a light diffusing material (B ′) in the resulting layer,
The method for producing a wavelength conversion layer according to any one of claims 11 to 13.