WO2022244669A1

WO2022244669A1 - Ink composition, light conversion layer, color filter, and light conversion film

Info

Publication number: WO2022244669A1
Application number: PCT/JP2022/020036
Authority: WO
Inventors: 麻里子利光; 栄志乙木; 浩一延藤; 祐貴野中
Original assignee: Dic株式会社
Priority date: 2021-05-20
Filing date: 2022-05-12
Publication date: 2022-11-24

Abstract

Provided is an ink composition from which a light conversion layer having excellent stability with respect to heat and excitation light can be formed. An ink composition according to the present invention is characterized by containing: light-emitting nanocrystal particles; a photopolymerizable compound; and a metal compound having a dithiocarbamic acid group, wherein the photopolymerizable compound includes a (meth)acrylate compound having an acrylic equivalent of at least 110. The metal compound is preferably a metal compound selected from the group consisting of a zinc compound, a sodium compound, and a copper compound.

Description

Ink composition, light conversion layer, color filter and light conversion film

The present invention relates to an ink composition, a light conversion layer, a color filter and a light conversion film.

Conventionally, a pixel part (color filter pixel part) in a display such as a liquid crystal display device is, for example, a curable resist containing red organic pigment particles or green organic pigment particles, an alkali-soluble resin and / or an acrylic monomer. It has been manufactured by photolithographic methods using materials.

In recent years, there has been a strong demand for lower power consumption of displays, and instead of the red organic pigment particles or green organic pigment particles, for example, quantum dots, quantum rods, and other inorganic phosphor particles. are being actively researched into photoconversion films and photoconversion layers such as color filter pixel portions for extracting red light or green light.

This light conversion layer is mounted on the backlight unit of the image display device. For example, when a light conversion film containing quantum dots that emit red light and quantum dots that emit green light is irradiated with blue light as excitation light, the red light and green light emitted from the quantum dots and the light conversion film White light can be obtained with the blue light that has passed through.

Further, the light conversion layer includes, for example, a red-emitting quantum dot layer that emits red fluorescence when excited by blue light and a green quantum dot layer that emits green fluorescence when excited by blue light on a substrate on which a black matrix is formed. It is formed by forming a luminescent quantum dot layer and a blue light transmission layer that transmits blue light. A liquid crystal display device or a self-luminous display device is configured by combining such a light conversion layer with an LED backlight that emits blue light or an organic EL element that emits blue light.

A display device with such a light conversion layer can increase light utilization efficiency more than a display device with a conventional color filter. In addition, since fluorescence emitted from the quantum dots and having a spectrum with a small half-value width can be used as it is for color display of the display device, the display device can have a wide color reproduction range.

For example, a method is known in which a photosensitive resin composition containing quantum dots is applied to one entire surface of a substrate and cured by ultraviolet irradiation to produce a light conversion film.

Alternatively, for example, the light conversion layer is formed by forming a coating film on one side of the substrate using a photosensitive resin composition containing quantum dots, patterning the coating film by photolithography, and then heating the resulting coating film. A method of hardening by treatment is known (see, for example, Patent Document 1).

However, the method of manufacturing color filters by photolithography has the disadvantage that the resist material other than the pixel portion, including the relatively expensive luminescent nanocrystal particles, is wasted due to the characteristics of the manufacturing method. Under these circumstances, in order to eliminate the waste of the resist material as described above, it is being investigated to form the pixel portion of the light conversion substrate using a curable ink composition by an inkjet method (inkjet method). (Patent Document 2).

JP 2016-53716 A WO2008/001693

When forming an optical film including a color filter pixel portion (hereinafter also simply referred to as "pixel portion") or a light conversion layer with an ink composition using luminescent nanocrystalline particles such as quantum dots, the quantum dots are unstable. Therefore, depending on the type of resin used as a binder, for example, external quantum efficiency (EQE) may decrease over time due to heating during color filter manufacturing or excitation light during display driving. may be lost.

Accordingly, one object of the present invention is to provide an ink composition having excellent stability against heat and excitation light, and a light conversion layer, color filter and light conversion film using the ink composition. do.

One aspect of the present invention contains luminescent nanocrystalline particles, a photopolymerizable compound, and a metal compound having a dithiocarbamic acid group, and the photopolymerizable compound has an acrylic equivalent of 110 or more (meth) The present invention relates to ink compositions containing acrylate compounds.

According to the ink composition of the aspect, it is possible to form a light conversion layer with excellent heat resistance and excitation light resistance, that is, a light conversion layer with little decrease in external quantum efficiency during heating and excitation light irradiation.

The metal compound having a dithiocarbamic acid group may preferably be a zinc compound, a sodium compound, or a copper compound, more preferably a zinc compound.

The (meth)acrylate compound is preferably a compound represented by the following formula (I).

[In formula (I), R ¹ represents a hydrogen atom or a methyl group, R ² represents an optionally substituted linear or branched alkylene group having 1 to 20 carbon atoms, m is 1 Represents an integer from ~10. Two R ^1s may be the same or different. ]

The photopolymerizable compound may further contain a monofunctional (meth)acrylate compound.

The monofunctional (meth)acrylate compound may be a monofunctional (meth)acrylate compound containing an alicyclic structure.

The ink composition may further contain a phenolic antioxidant.

The ink composition may further contain a phosphorus antioxidant.

The ink composition can be used to form a light conversion layer. That is, the ink composition may be an ink composition for forming a light conversion layer.

The ink composition can be used in an inkjet method. That is, the ink composition may be an inkjet ink.

Another aspect of the present invention includes a plurality of pixel portions and a light shielding portion provided between the plurality of pixel portions, wherein the plurality of pixel portions includes a cured product of the ink composition of the above aspect. The present invention relates to a light conversion layer having an optical pixel portion.

The light conversion layer contains luminescent nanocrystalline particles that absorb light with a wavelength in the range of 420 to 480 nm and emit light with an emission peak wavelength in the range of 605 to 665 nm as the luminescent pixel portion. and a second luminescent pixel portion containing luminescent nanocrystalline particles that absorb light with a wavelength in the range of 420 to 480 nm and emit light with an emission peak wavelength in the range of 500 to 560 nm. Be prepared.

The light conversion layer may further comprise a non-luminous pixel portion containing light scattering particles.

Another aspect of the present invention relates to a color filter comprising the light conversion layer described above.

Another aspect of the present invention relates to a light conversion film containing a cured product of the ink composition described above.

According to the present invention, it is possible to provide an ink composition capable of forming a light conversion layer with excellent stability against heat and excitation light.

FIG. 1 is a schematic cross-sectional view showing one embodiment of a color filter according to one embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing one embodiment of the light conversion film of one embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail. In this specification, a numerical range indicated using "-" indicates a range including the numerical values before and after "-" as the minimum and maximum values, respectively. In the present specification, the term “cured product of the ink composition” refers to a product obtained by curing a curable component in the ink composition (when the ink composition contains a solvent component, the ink composition after drying). It is something that can be done. The cured ink composition after drying may not contain an organic solvent.

<Ink composition>
The ink composition of one embodiment contains luminescent nanocrystalline particles, a photopolymerizable compound, and a metal compound having a dithiocarbamic acid group, and the photopolymerizable compound has an acrylic equivalent of 110 or more (meta ) including acrylate compounds.

The ink composition is used for forming a light conversion layer (for example, for forming a color filter pixel portion or for forming a light conversion film), which is used for forming a pixel portion of a light conversion layer of a color filter or the like. It is an ink composition.

According to the above ink composition, it is possible to obtain a light conversion layer whose external quantum efficiency is less likely to decrease when heated or irradiated with excitation light.

Although the reason why the ink composition achieves the effects described above is not clear, the present inventors speculate as follows. That is, radicals and oxygen remain in the cured light conversion layer, and the radicals react rapidly with oxygen to form peroxy radicals and hydroperoxides, thereby degrading the luminescent nanocrystalline particles. Heating or irradiation of excitation light enhances the activity of the luminescent nanocrystalline particles, and thus accelerates the deterioration of the luminescent nanocrystalline particles, resulting in more significant deterioration. It is believed that the metal compound having a dithiocarbamic acid group of the present embodiment has a function of scavenging radicals and suppresses deterioration of the luminescent nanocrystalline particles. In addition, it is presumed that the metal compound having a dithiocarbamic acid group is decomposed by heat and light and reacts with the surface of the luminescent nanocrystalline particles, thereby having the effect of protecting the luminescent nanocrystalline particles from oxidation. Furthermore, by using a (meth)acrylate compound having an acrylic equivalent of 110 or more, the adhesion between the substrate and the light conversion layer is improved, and by suppressing the intrusion of oxygen and moisture from the interface, the luminescent nano It is considered that the deterioration of crystal grains is suppressed.

Further, according to the ink composition, a light conversion layer having excellent external quantum efficiency can be obtained. Furthermore, according to the ink composition, it is possible to obtain excellent ejection stability in the inkjet method. That is, the ink composition can be suitably used for the inkjet method.

Furthermore, according to the ink composition of the present invention, since the luminescent nanocrystalline particles are uniformly dispersed, excellent applicability can be obtained in a printing method using a coating method (hereinafter referred to as “coating method”). can. That is, the ink composition of the present invention can be suitably used in coating methods.

By the way, since the pixel portion is used in an environment exposed to external light, it is required that the external quantum efficiency does not deteriorate due to external light (light stability). However, it cannot be said that a pixel portion having sufficient photostability can be obtained. On the other hand, the ink composition tends to suppress the decrease in external quantum efficiency due to external light. That is, according to the ink composition, a light conversion layer having excellent light stability can be formed.

The ink composition of one embodiment can be applied as an ink for manufacturing color filters. In view of the fact that the pixel portion (light conversion layer) can be formed only by using the amount necessary for the above, it is preferable to prepare and use it so as to be suitable for the inkjet method rather than the photolithographic method. Also, the ink composition of one embodiment is preferably carried between barrier films and used as a wavelength conversion film.

The ink composition contains, in addition to luminescent nanocrystalline particles, a photopolymerizable compound, and a metal compound having a dithiocarbamic acid group, an organic ligand (hereinafter sometimes referred to as a "ligand"), light scattering particles, Other components such as polymeric dispersants, organic solvents, etc. may be further included. An ink composition according to one embodiment will be described below, taking an ink composition for color filters (inkjet ink for color filters) used in an inkjet method as an example.

[Luminescent nanocrystalline particles]
Luminescent nanocrystalline particles are nano-sized crystals that absorb excitation light and emit fluorescence or phosphorescence. For example, the maximum particle diameter measured by a transmission electron microscope or scanning electron microscope is 100 nm or less. It is crystalline.

A luminescent nanocrystalline particle can, for example, emit light (fluorescence or phosphorescence) of a wavelength different from the absorbed wavelength by absorbing light of a predetermined wavelength. The luminescent nanocrystalline particles may be red luminescent nanocrystalline particles (red luminescent nanocrystalline particles) that emit light having an emission peak wavelength in the range of 605-665 nm (red light), Green luminescent nanocrystalline particles (green luminescent nanocrystalline particles) that emit light with an emission peak wavelength in the range of 420-480 nm (blue light). ), may be blue-emitting nanocrystalline particles (blue-emitting nanocrystalline particles). In this embodiment, the ink composition preferably contains at least one of these luminescent nanocrystalline particles. In addition, the light absorbed by the luminescent nanocrystalline particles is, for example, light (blue light) with a wavelength in the range of 400 nm or more and less than 500 nm (especially light with a wavelength in the range of 420 to 480 nm), or in the range of 200 nm to 400 nm. (ultraviolet light). The emission peak wavelength of the luminescent nanocrystalline particles can be confirmed, for example, in the fluorescence spectrum or phosphorescence spectrum measured using a spectrofluorometer.

The red-emitting nanocrystalline particles are 665 nm or less, 663 nm or less, 660 nm or less, 658 nm or less, 655 nm or less, 653 nm or less, 651 nm or less, 650 nm or less, 647 nm or less, 645 nm or less, 643 nm or less, 640 nm or less, 637 nm or less, 635 nm or less. , 632 nm or less, or 630 nm or less, preferably 628 nm or more, 625 nm or more, 623 nm or more, 620 nm or more, 615 nm or more, 610 nm or more, 607 nm or more, or 605 nm or more. These upper and lower limits can be combined arbitrarily. In addition, in the following similar description, the upper limit and the lower limit that are individually described can be arbitrarily combined.

Green-emitting nanocrystalline particles have an emission peak wavelength of 560 nm or less, 557 nm or less, 555 nm or less, 550 nm or less, 547 nm or less, 545 nm or less, 543 nm or less, 540 nm or less, 537 nm or less, 535 nm or less, 532 nm or less, or 530 nm or less. It preferably has an emission peak wavelength of 528 nm or more, 525 nm or more, 523 nm or more, 520 nm or more, 515 nm or more, 510 nm or more, 507 nm or more, 505 nm or more, 503 nm or more, or 500 nm or more.

The blue-emitting nanocrystalline particles have an emission peak wavelength of 480 nm or less, 477 nm or less, 475 nm or less, 470 nm or less, 467 nm or less, 465 nm or less, 463 nm or less, 460 nm or less, 457 nm or less, 455 nm or less, 452 nm or less, or 450 nm or less. It preferably has an emission peak wavelength of 450 nm or more, 445 nm or more, 440 nm or more, 435 nm or more, 430 nm or more, 428 nm or more, 425 nm or more, 422 nm or more, or 420 nm or more.

According to the solution of the Schrödinger wave equation of the well-type potential model, the wavelength (emission color) of the light emitted by the luminescent nanocrystalline particles depends on the size (e.g., particle diameter) of the luminescent nanocrystalline particles. It also depends on the energy gap of the crystal grains. Therefore, the emission color can be selected by changing the constituent material and size of the luminescent nanocrystalline particles used.

The luminescent nanocrystalline particles may be luminescent nanocrystalline particles containing a semiconductor material (luminescent semiconductor nanocrystalline particles). Luminescent semiconductor nanocrystal particles include quantum dots and quantum rods. Among these, quantum dots are preferable from the viewpoint that the emission spectrum can be easily controlled, the reliability can be secured, the production cost can be reduced, and the mass productivity can be improved.

The luminescent semiconductor nanocrystal particles may consist solely of a core comprising the first semiconductor material, comprising a core comprising the first semiconductor material and a second semiconductor material different from the first semiconductor material, wherein and a shell covering at least a portion of the core. In other words, the structure of the luminescent semiconductor nanocrystal particles may be a structure consisting of only a core (core structure) or a structure consisting of a core and a shell (core/shell structure). In addition, the luminescent semiconductor nanocrystal particle contains a third semiconductor material different from the first and second semiconductor materials in addition to the shell (first shell) containing the second semiconductor material, It may further have a shell (second shell) that covers at least part of it. In other words, the structure of the luminescent semiconductor nanocrystal particles may be a structure consisting of a core, a first shell and a second shell (core/shell/shell structure). Each of the core and shell may be a mixed crystal containing two or more semiconductor materials (eg, CdSe+CdS, CIS+ZnS, etc.).

Luminescent nanocrystalline particles are selected as semiconductor materials from the group consisting of II-VI semiconductors, III-V semiconductors, I-III-VI semiconductors, IV semiconductors and I-II-IV-VI semiconductors. It preferably contains at least one semiconductor material that

Specific semiconductor materials include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, ＣｄＺｎＴｅ、ＣｄＨｇＳ、ＣｄＨｇＳｅ、ＣｄＨｇＴｅ、ＨｇＺｎＳ、ＨｇＺｎＳｅ、ＣｄＨｇＺｎＴｅ、ＣｄＺｎＳｅＳ、ＣｄＺｎＳｅＴｅ、ＣｄＺｎＳＴｅ、ＣｄＨｇＳｅＳ、ＣｄＨｇＳｅＴｅ、ＣｄＨｇＳＴｅ、ＨｇＺｎＳｅＳ、ＨｇＺｎＳｅＴｅ、ＨｇＺｎＳＴｅ；ＧａＮ、ＧａＰ、ＧａＡｓ、ＧａＳｂ、ＡｌＮ、ＡｌＰ、ＡｌＡｓ、ＡｌＳｂ、ＩｎＮ、 InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb; SnPbSTe; includes Si, Ge, SiC, SiGe, AgInSe2, _CuGaSe2 , _CuInS2 , _CuGaS2 , _CuInSe2 , _AgInS2 , _AgInGaS , _AgGaSe2 , _AgGaS2 , C, Si and Ge. Luminescent semiconductor nanocrystalline particles are CdS, CdSe, CdTe, ZnS, and CdS, CdSe, CdTe, ZnS, and CdS, CdSe, CdTe, ZnS, and CdS, CdSe, CdTe, ZnS, and CdS. ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, InP, InAs, InSb, GaP, GaAs, GaSb, _AgInS2 , _AgInGaS , _AgInSe2 , _AgInTe2 , _AgGaS2 , _AgGaSe2 , _AgGaTe2 , _CuInS2 , CuInSe It preferably contains at least one selected from the group consisting of _CuInTe2 , _CuGaS2 , _CuGaSe2 , _CuGaTe2 , Si, C, _Ge and _Cu2ZnSnS4 .

Examples of red-emitting semiconductor nanocrystal particles include nanocrystal particles of CdSe and nanocrystal particles having a core/shell structure in which the shell portion is CdS and the inner core portion is CdSe. particles, nanocrystalline particles with a core/shell structure, where the shell portion is CdS and the inner core portion is ZnSe, mixed crystal nanocrystalline particles of CdSe and ZnS, InP nanocrystalline particles A crystalline particle, a nanocrystalline particle with a core/shell structure, wherein the shell portion is ZnS and the inner core portion is InP, a nanocrystalline particle with a core/shell structure, Nanocrystalline particles whose shell portion is a mixed crystal of ZnS and ZnSe and whose inner core portion is InP, nanocrystalline particles of mixed crystal of CdSe and CdS, nanocrystalline particles of mixed crystal of ZnSe and CdS, core /Nanocrystalline particles with a shell/shell structure, wherein the first shell portion is ZnSe, the second shell portion is ZnS, and the inner core portion is InP, core/shell / A nanocrystalline particle having a shell structure, wherein the first shell portion is a mixed crystal of ZnS and ZnSe, the second shell portion is ZnS, and the inner core portion is InP etc.

Examples of green-emitting semiconductor nanocrystalline particles include nanocrystalline particles of CdSe, nanocrystalline particles of a mixed crystal of CdSe and ZnS, and nanocrystalline particles having a core/shell structure, the shell portion of which is ZnS. and a nanocrystalline particle having an inner core of InP, a nanocrystalline particle having a core/shell structure, wherein the shell is a mixed crystal of ZnS and ZnSe and the inner core is InP Crystalline particles, nanocrystalline particles with a core/shell/shell structure, wherein the first shell portion is ZnSe, the second shell portion is ZnS, and the inner core portion is InP , a nanocrystalline particle with a core/shell/shell structure, wherein the first shell portion is a mixed crystal of ZnS and ZnSe, the second shell portion is ZnS, and the inner core portion is InP certain nanocrystalline particles and the like.

Examples of blue-emitting semiconductor nanocrystalline particles include ZnSe nanocrystalline particles, ZnS nanocrystalline particles, and nanocrystalline particles having a core/shell structure, wherein the shell portion is ZnSe and the inner core portion is is ZnS, nanocrystalline particles of CdS, nanocrystalline particles having a core/shell structure, wherein the shell portion is ZnS and the inner core portion is InP, core/shell A nanocrystalline particle with a structure, wherein the shell part is a mixed crystal of ZnS and ZnSe and the inner core part is InP, a nanocrystalline particle with a core/shell/shell structure. a nanocrystalline particle having a first shell portion of ZnSe, a second shell portion of ZnS, and an inner core portion of InP, a nanocrystalline particle having a core/shell/shell structure, Examples include nanocrystalline particles in which the first shell portion is a mixed crystal of ZnS and ZnSe, the second shell portion is ZnS, and the inner core portion is InP.

With the same chemical composition, the semiconductor nanocrystal particles can change the color of light emitted from the particles to either red or green by changing the average particle size of the particles themselves. In addition, it is preferable to use semiconductor nanocrystal particles that themselves have the least adverse effect on the human body or the like. When semiconductor nanocrystal particles containing cadmium, selenium, etc. are used as luminescent nanocrystal particles, semiconductor nanocrystal particles that do not contain the above elements (cadmium, selenium, etc.) as much as possible are selected and used alone. is preferably used in combination with other luminescent nanocrystalline particles so as to minimize the

The luminescent nanocrystalline particles may be nanocrystals made of metal halide from the viewpoint of obtaining an emission peak with a narrower half-width.

A nanocrystal made of metal halide is a compound semiconductor containing A, M and X, and is a compound represented by the general formula: AaMbXc.
In the formula, A represents a monovalent cation and is at least one of an organic cation and a metal cation. Organic cations include ammonium, formamidinium, guanidinium, imidazolium, pyridinium, pyrrolidinium, protonated thiourea and the like, and metal cations include cations such as Cs, Rb, K, Na and Li.
M represents a metal ion and is at least one metal cation. Metal cations selected from groups 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14 and 15 cations. More preferably Ag, Au, Bi, Ca, Ce, Co, Cr, Cu, Eu, Fe, Ga, Ge, Hf, In, Ir, Mg, Mn, Mo, Na, Nb, Nd, Ni, Os, Cations such as Pb, Pd, Pt, Re, Rh, Ru, Sb, Sc, Sm, Sn, Sr, Ta, Te, Ti, V, W, Zn, and Zr are included. X is at least one anion. Examples of anions include halide ions such as chloride ions, bromide ions, iodide ions, and cyanide ions.
a is 1-7, b is 1-4, and c is 3-16.
The emission wavelength (emission color) of such nanocrystals can be controlled by adjusting the particle size and the type and abundance of anions that constitute the X site.

Specifically, the compound represented by the general _formula _AaMmXx is _AMX _, _A4MX , _AMX2 , _AMX3 , _A2MX3 _, _AM2X3 , _A2MX4 _, _A2MX ₅ _, _A3MX5 _, _A3M2X5 _, _A3MX6 _, _A4MX6 _, _AM2X6 _, _A2MX6 _, _A4M2X6 _, _A3MX8 _, _A3M2 _{_} _{_} Compounds represented by X ₉ , A ₃ M ₃ X ₉ , A ₂ M ₂ X ₁₀ and A ₇ M ₃ X ₁₆ are preferred.
wherein A is at least one of an organic cation and a metal cation. Organic cations include ammonium, formamidinium, guanidinium, imidazolium, pyridinium, pyrrolidinium, protonated thiourea and the like, and metal cations include cations such as Cs, Rb, K, Na and Li.
wherein M is at least one metal cation. Specifically, ^one metal _cation ( _M1 ), ^two metal cations ( _M1αM2β ), ^three metal _{cations (M1αM2βM3γ} ⁾ _, ^four metal cations (M ¹ _α M ² _β M ³ _γ M ⁴ _δ ) and the like. However, α, β, γ, and δ each represent a real number between 0 and 1, and α+β+γ+δ=1. Metal cations selected from groups 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14 and 15 cations. More preferably Ag, Au, Bi, Ca, Ce, Co, Cr, Cu, Eu, Fe, Ga, Ge, Hf, In, Ir, Mg, Mn, Mo, Na, Nb, Nd, Ni, Os, Cations such as Pb, Pd, Pt, Re, Rh, Ru, Sb, Sc, Sm, Sn, Sr, Ta, Te, Ti, V, W, Zn, and Zr are included.
In the formula, X is an anion containing at least one halogen. Specifically, one type of halogen anion (X ¹ ), two types of halogen anions (X ¹ _α X ² _β ), and the like are included. Examples of anions include chloride ions, bromide ions, iodide ions, cyanide ions, and the like, including at least one halide ion.

The compound composed of the metal halide represented _by the _above general formula _AaMmXx is doped with metal ions such as Bi, Mn, Ca, Eu, Sb, and Yb in order to improve the light emission characteristics. may be

Among the compounds composed of metal _halides represented by the general formula _AaMmXx , the compound having a perovskite-type crystal structure is adjusted by adjusting the particle size, the type and abundance of metal cations constituting the _M site, Furthermore, it is particularly preferable for use as a semiconductor nanocrystal in that the emission wavelength (emission color) can be controlled by adjusting the type and abundance of anions that constitute the X site. Specifically, compounds represented by AMX ₃ , A ₃ MX ₅ , A ₃ MX ₆ , A ₄ MX ₆ and A ₂ MX ₆ are preferred. A, M and X in the formula are as described above. Also, the compound having the perovskite crystal structure may be doped with metal ions such as Bi, Mn, Ca, Eu, Sb, and Yb, as described above.

Among compounds exhibiting a perovskite crystal structure, A is Cs, Rb, K, Na, or Li, and M is one kind of metal cation (M ¹ ), or two kinds of It is preferably a metal cation (M ¹ _α M ² _β ) and X is chloride, bromide or iodide. However, α and β each represent a real number between 0 and 1, and α+β=1. Specifically, M may be selected from Ag, Au, Bi, Cu, Eu, Fe, Ge, K, In, Na, Mn, Pb, Pd, Sb, Si, Sn, Yb, Zn, Zr. preferable.

Nanocrystals 911 using Pb as M such as CsPbBr ₃ , CH ₃ NH ₃ PbBr ₃ , CHN ₂ H ₄ PbBr ₃ , etc., as specific compositions of nanocrystals made of metal halide and having a perovskite crystal structure, have a light intensity It is preferable because it is excellent in quantum efficiency as well as excellent in In addition, CsSnBr ₃ , CsSnCl ₃ , CsSnBr _1.5 Cl _1.5 , Cs ₃ Sb ₂ Br ₉ , (CH ₃ NH ₃ ) ₃ Bi ₂ Br ₉ , (C ₄ H ₉ NH ₃ ) ₂ AgBiBr ₆ , Nanocrystals using metal cations other than Pb as M are preferred due to their low toxicity and low environmental impact.

The shape of the luminescent nanocrystalline particles is not particularly limited, and may be any geometric shape or any irregular shape. The shape of the luminescent nanocrystalline particles may be, for example, spherical, ellipsoidal, pyramidal, disk-like, branch-like, net-like, rod-like, and the like. However, as the luminescent nanocrystalline particles, the uniformity and fluidity of the ink composition can be further enhanced by using particles with a less directional particle shape (e.g., spherical, regular tetrahedral particles, etc.). is preferred.

The average particle diameter (volume average diameter) of the luminescent nanocrystalline particles may be 1 nm or more, or 1.5 nm, from the viewpoints of easily obtaining light emission of a desired wavelength and from the viewpoint of excellent dispersibility and storage stability. or more, or 2 nm or more. From the viewpoint of easily obtaining a desired emission wavelength, it may be 40 nm or less, 30 nm or less, or 20 nm or less. The average particle diameter (volume average diameter) of the luminescent nanocrystalline particles is obtained by measuring with a transmission electron microscope or scanning electron microscope and calculating the volume average diameter.

From the viewpoint of dispersion stability, the luminescent nanocrystalline particles preferably have organic ligands on their surfaces. Organic ligands may be coordinated to the surface of the luminescent nanocrystalline particles, for example. In other words, the surface of the luminescent nanocrystalline particles may be passivated by organic ligands. Moreover, when the ink composition further contains a polymer dispersant, which will be described later, the luminescent nanocrystalline particles may have the polymer dispersant on their surfaces. In this embodiment, for example, the organic ligand is removed from the luminescent nanocrystalline particles having the above-described organic ligand, and the organic ligand is exchanged with the polymeric dispersant, thereby dispersing the polymeric dispersant on the surface of the luminescent nanocrystalline particles. may be combined. However, from the viewpoint of dispersion stability when used as an inkjet ink, it is preferable that a polymer dispersant is added to the luminescent nanocrystalline particles with the organic ligands still coordinated.

As the organic ligand, a functional group for ensuring affinity with a photopolymerizable compound, a thermosetting resin, an organic solvent, etc. (hereinafter also simply referred to as an "affinity group"), and a luminescent nanocrystalline particle. It is preferably a compound having a bondable functional group (a functional group for ensuring adsorption to the luminescent nanocrystalline particles). The affinity group may be a substituted or unsubstituted aliphatic hydrocarbon group. The aliphatic hydrocarbon group may be linear or have a branched structure. Also, the aliphatic hydrocarbon group may or may not have an unsaturated bond. The substituted aliphatic hydrocarbon may be a group in which some carbon atoms of an aliphatic hydrocarbon group are substituted with oxygen atoms. Substituted aliphatic hydrocarbon groups may include, for example, (poly)oxyalkylene groups. Here, the "(poly)oxyalkylene group" means at least one of an oxyalkylene group and a polyoxyalkylene group in which two or more alkylene groups are linked by an ether bond. Functional groups that can bind to luminescent nanocrystalline particles include, for example, hydroxyl groups, amino groups, carboxyl groups, thiol groups, phosphate groups, phosphonic acid groups, phosphine groups, phosphine oxide groups, and alkoxysilyl groups. Examples of organic ligands include TOP (trioctylphosphine), TOPO (trioctylphosphine oxide), oleic acid, linoleic acid, linolenic acid, ricinoleic acid, gluconic acid, 16-hydroxyhexadecanoic acid, 12-hydroxystearic acid, N - lauroylsarcosine, N-oleylsarcosine, oleylamine, octylamine, trioctylamine, hexadecylamine, octanethiol, dodecanethiol, hexylphosphonic acid (HPA), tetradecylphosphonic acid (TDPA), phenylphosphonic acid, and octylphosphine acid (OPA).

In one embodiment, the organic ligand may be an organic ligand represented by formula (1-1) below.

[In formula (1-1), p represents an integer of 0 to 50, and q represents an integer of 0 to 50. ]

In the organic ligand represented by formula (1-1), at least one of p and q is preferably 1 or more, more preferably both p and q are 1 or more.

The organic ligand may be, for example, an organic ligand represented by formula (1-2) below.

In formula (1-2), A ¹ represents a monovalent group containing a carboxyl group, A ² represents a monovalent group containing a hydroxyl group, and R is a hydrogen atom, a methyl group, or an ethyl group. , L represents a substituted or unsubstituted alkylene group, and r represents an integer of 0 or more. The number of carboxyl groups in the monovalent group containing a carboxyl group may be 2 or more, 2 or more and 4 or less, or 2. The number of carbon atoms in the alkylene group represented by L may be, for example, 1-10. In the alkylene group represented by L, some of the carbon atoms may be substituted with hetero atoms, and at least one hetero atom selected from the group consisting of oxygen atoms, sulfur atoms and nitrogen atoms. good too. r may be, for example, an integer of 1-100, or an integer of 10-20.

The organic ligand may be an organic ligand represented by the following formula (1-2A) from the viewpoint of excellent external quantum efficiency of the pixel portion (cured product of the ink composition).

In formula (1-2A), r has the same meaning as above.

The content of the organic ligand in the ink composition is 15 parts by mass or more and 20 parts by mass with respect to 100 parts by mass of the luminescent nanocrystalline particles, from the viewpoint of the dispersion stability of the luminescent nanocrystalline particles and the maintenance of the light emission properties. Above, it is preferable that it is 25 mass parts or more, 30 mass parts or more, 35 mass parts or more, or 40 mass parts or more. From the viewpoint of keeping the viscosity of the ink composition low, the content of the organic ligand in the ink composition is 50 parts by mass or less, 45 parts by mass or less, or 40 parts by mass or less relative to 100 parts by mass of the luminescent nanocrystalline particles. It is preferably 30 parts by mass or less.

As the luminescent nanocrystalline particles, those dispersed in a colloidal form in an organic solvent, a photopolymerizable compound, or the like can be used. The surfaces of the luminescent nanocrystalline particles dispersed in the organic solvent are preferably passivated with the above-described organic ligands. As the organic solvent, the below-described organic solvent contained in the ink composition is used.

Commercially available products can be used as the luminescent nanocrystalline particles. Commercially available luminescent nanocrystalline particles include, for example, indium phosphide/zinc sulfide, D-dot, CuInS/ZnS from NN-Labs, and InP/ZnS from Aldrich.

In addition, when cations are present on the surface of the nanocrystal, a ligand having a binding group that binds to the cation may be used, and the ligand can stabilize the surface of the nanocrystal.

Examples of the binding group include a carboxyl group, a carboxylic anhydride group, an amino group, an ammonium group, a mercapto group, a phosphine group, a phosphine oxide group, a phosphoric acid group, a phosphonic acid group, a phosphinic acid group, a sulfonic acid group and At least one of boronic acid groups is preferred, and at least one of carboxyl and amino groups is more preferred. Examples of such ligands include carboxyl group- or amino group-containing compounds and the like, and these ligands can be used singly or in combination of two or more.

Examples of carboxyl group-containing compounds include linear or branched aliphatic carboxylic acids having 1 to 30 carbon atoms. Specific examples of such carboxyl group-containing compounds include arachidonic acid, crotonic acid, trans-2-decenoic acid, erucic acid, 3-decenoic acid, cis-4,7,10,13,16,19-docosahexaenoic acid. , 4-decenoic acid, all cis-5,8,11,14,17-eicosapentaenoic acid, all cis-8,11,14-eicosatrienoic acid, cis-9-hexadecenoic acid, trans-3-hexenoic acid , trans-2-hexenoic acid, 2-heptenoic acid, 3-heptenoic acid, 2-hexadecenoic acid, linolenic acid, linoleic acid, γ-linolenic acid, 3-nonenoic acid, 2-nonenoic acid, trans-2-octenoic acid , petroselinic acid, elaidic acid, oleic acid, 3-octenoic acid, trans-2-pentenoic acid, trans-3-pentenoic acid, ricinoleic acid, sorbic acid, 2-tridecenoic acid, cis-15-tetracosenoic acid, 10-undecene acid, 2-undecenoic acid, acetic acid, butyric acid, behenic acid, cerotic acid, decanoic acid, arachidic acid, heneicosanoic acid, heptadecanoic acid, heptanoic acid, hexanoic acid, heptacosanoic acid, lauric acid, myristic acid, melisic acid, octacosanoic acid, Nonadecanic acid, nonacosanoic acid, n-octanoic acid, palmitic acid, isopalmitic acid, pentadecanoic acid, propionic acid, pentacosanoic acid, nonanoic acid, stearic acid, lignoceric acid, tricosanoic acid, tridecanoic acid, undecanoic acid, valeric acid, etc. be done.

Examples of amino group-containing compounds include linear or branched aliphatic amines having 1 to 30 carbon atoms. Specific examples of such amino group-containing compounds include 1-aminoheptadecane, 1-aminononadecane, heptadecane-9-amine, stearylamine, oleylamine, 2-n-octyl-1-dodecylamine, allylamine, and amylamine. , 2-ethoxyethylamine, 3-ethoxypropylamine, isobutylamine, isoamylamine, 3-methoxypropylamine, 2-methoxyethylamine, 2-methylbutylamine, neopentylamine, propylamine, methylamine, ethylamine, butylamine, hexylamine , heptylamine, n-octylamine, 1-aminodecane, nonylamine, 1-aminoundecane, dodecylamine, 1-aminopentadecane, 1-aminotridecane, hexadecylamine, tetradecylamine and the like.

In addition, the ligand having a bonding group that binds to the cation on the surface of the nanocrystal may be a silane compound containing Si and having a reactive group that forms a siloxane bond by hydrolysis. can further stabilize the nanocrystal surface.

As the reactive group, a hydrolyzable silyl group such as a silanol group or an alkoxysilyl group having 1 to 6 carbon atoms is preferable because a siloxane bond is easily formed.

Examples of binding groups include carboxyl groups, amino groups, ammonium groups, mercapto groups, phosphine groups, phosphine oxide groups, phosphoric acid groups, phosphonic acid groups, phosphinic acid groups, sulfonic acid groups, boronic acid groups, and the like. . Among them, the binding group is preferably at least one of a carboxyl group, a mercapto group and an amino group. These binding groups have a higher affinity for the cations contained in the nanocrystals than the reactive groups described above. Therefore, the ligands are coordinated with the bonding groups on the nanocrystal side, and the silica layer can be formed more easily and reliably.

As the silane compound containing Si and having a reactive group that forms a siloxane bond, one or more silicon compounds containing a bonding group may be used, or two or more may be used in combination.
Preferably, any one of a carboxyl group-containing silicon compound, an amino group-containing silicon compound, and a mercapto group-containing silicon compound is contained, or two or more of them can be used in combination.

Specific examples of carboxyl group-containing silicon compounds include 3-(trimethoxysilyl)propionic acid, 3-(triethoxysilyl)propionic acid, 2-, carboxyethylphenylbis(2-methoxyethoxy)silane, N- [3-(trimethoxysilyl)propyl]-N'-carboxymethylethylenediamine, N-[3-(trimethoxysilyl)propyl]phthalamide, N-[3-(trimethoxysilyl)propyl]ethylenediamine-N,N' , N′-triacetic acid and the like.

On the other hand, specific examples of amino group-containing silicon compounds include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl)-3-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldipropoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldiiso Propoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyl Tripropoxysilane, N-(2-aminoethyl)-3-aminopropyltriisopropoxysilane, N-(2-aminoethyl)-3-aminoisobutyldimethylmethoxysilane, N-(2-aminoethyl)-3- Aminoisobutylmethyldimethoxysilane, N-(2-aminoethyl)-11-aminoundecyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylsilanetriol, 3-triethoxysilyl-N-(1 ,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N,N-bis[3-(trimethoxysilyl)propyl]ethylenediamine, (aminoethylaminoethyl)phenyltrimethoxysilane, (aminoethylaminoethyl)phenyltriethoxysilane, (aminoethylaminoethyl)phenyltripropoxysilane, (aminoethylaminoethyl)phenyltriisopropoxysilane, (aminoethylaminomethyl)phenyltrimethoxysilane, (aminoethylaminomethyl) ) phenyltriethoxysilane, (aminoethylaminomethyl)phenyltripropoxysilane, (aminoethylaminomethyl)phenyltriisopropoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane, N -(vinylbenzyl)-2-aminoethyl-3-aminopropylmethyldimethoxysilane, N-β-(N-vinylbenzylaminoethyl)-N-γ-(N-vinylbenzyl)-γ-aminopropyltrimethoxysilane , N-β-(N-di(vinylbenzyl)aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(N-di(vinylbenzyl) Dyl)aminoethyl)-N-γ-(N-vinylbenzyl)-γ-aminopropyltrimethoxysilane, methylbenzylaminoethylaminopropyltrimethoxysilane, dimethylbenzylaminoethylaminopropyltrimethoxysilane, benzylaminoethylaminopropyl Trimethoxysilane, benzylaminoethylaminopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, 3-(N-phenyl)aminopropyltrimethoxysilane, N,N-bis[3-(trimethoxysilyl)propyl]ethylenediamine , (aminoethylaminoethyl)phenethyltrimethoxysilane, (aminoethylaminoethyl)phenethyltriethoxysilane, (aminoethylaminoethyl)phenethyltripropoxysilane, (aminoethylaminoethyl)phenethyltriisopropoxysilane, (aminoethylamino methyl)phenethyltrimethoxysilane, (aminoethylaminomethyl)phenethyltriethoxysilane, (aminoethylaminomethyl)phenethyltripropoxysilane, (aminoethylaminomethyl)phenethyltriisopropoxysilane, N-[2-[3-( Trimethoxysilyl)propylamino]ethyl]ethylenediamine, N-[2-[3-(triethoxysilyl)propylamino]ethyl]ethylenediamine, N-[2-[3-(tripropoxysilyl)propylamino]ethyl]ethylenediamine , N-[2-[3-(triisopropoxysilyl)propylamino]ethyl]ethylenediamine and the like.

Specific examples of mercapto group-containing silicon compounds include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, and 2-mercaptoethyl. trimethoxysilane, 2-mercaptoethyltriethoxysilane, 2-mercaptoethylmethyldimethoxysilane, 2-mercaptoethylmethyldiethoxysilane, 3-[ethoxybis(3,6,9,12,15-pentoxaoctacosane-1 -yloxy)silyl]-1-propanethiol and the like.

The silica layer can be formed by coordinating ligands such as oleic acid and 3-aminopropyltrimethoxysilane to the surface of the nanocrystals and further reacting with 3-aminopropyltrimethoxysilane. can.

The thickness of the silica layer is preferably 0.5-50 nm, more preferably 1.0-30 nm. A luminescent particle having such a thick silica layer can sufficiently improve the stability of the nanocrystal against heat and light.

The thickness of the silica layer can be changed by adjusting the number of atoms (chain length) of the connecting structure that connects the binding group and the reactive group of the ligand.

Specifically, the luminescent particles having a silica layer are composed of a solution containing a raw material compound of nanocrystals, a compound having a bonding group that binds to cations contained in the nanocrystals, and Si to form a siloxane bond. After mixing with a solution containing a compound having a reactive group to be obtained, the reactive group in the compound containing Si coordinated to the surface of the precipitated nanocrystal and having a reactive group capable of forming a siloxane bond is condensed. It can be easily produced by At this time, there are a method of manufacturing with heating and a method of manufacturing without heating.

First, a method for producing luminescent particles having a silica layer by heating will be described. Solutions containing two kinds of raw material compounds for synthesizing semiconductor nanocrystals by reaction are prepared respectively. At this time, a compound having a bonding group that binds to cations contained in the nanocrystals is added to one of the two solutions, and a compound containing Si and having a reactive group capable of forming a siloxane bond is added to the other. Keep These are then mixed under an inert gas atmosphere and reacted at a temperature of 140 to 260°C. Next, a method of precipitating nanocrystals by cooling to −20 to 30° C. and stirring may be used. The precipitated nanocrystals have a silica layer having siloxane bonds formed on the surface of the nanocrystals, and the nanocrystals can be obtained by a conventional method such as centrifugation.

Next, a method for producing luminescent particles having a silica layer without heating will be described. A solution containing a raw material compound for semiconductor nanocrystals and a compound having a bonding group that binds to a cation contained in the nanocrystal (excluding compounds containing Si and having a reactive group capable of forming a siloxane bond) was added to the solution containing Si. A method of precipitating nanocrystals by dropping and mixing a compound containing a reactive group capable of forming a siloxane bond in an organic solvent, which is a poor solvent for nanocrystals, in the atmosphere. mentioned. The amount of the organic solvent used is preferably 10 to 1000 times the mass of the semiconductor nanocrystals. In addition, the deposited nanocrystals have a silica layer having a siloxane bond formed on the surface of the nanocrystals, and can be obtained by a standard method such as centrifugation.

A silica layer may be additionally formed on the surface of the nanocrystal on which the shell layer having siloxane bonds is formed. When a silica layer is additionally formed, first, a silane compound is mixed with nanocrystals on which a silica layer having siloxane bonds is formed, and siloxane bonds are formed by hydrolysis to form a shell layer. In the case of additionally forming a silica layer, a reaction field is formed by adsorbing a polymer having a structural unit containing a basic group, and then a silane compound is mixed and hydrolyzed to form a siloxane bond to form a silica layer. good too.

The silane compound is preferably, for example, a compound represented by the following formula (C1).

In the formula, R ^C1 and R ^C2 each independently represent an alkyl group, R ^C3 and R ^C4 each independently represent a hydrogen atom or an alkyl group, n represents 0 or 1, m is an integer of 1 or more represents m is preferably an integer of 10 or less.

Specific examples of the compound represented by formula (C1) include tetrabutoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyl trimethoxysilane, phenyltrimethoxysilane, vinyltriethoxysilane, n-propyltrimethoxysilane, isopropyltrimethoxysilane, n-butyltriethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, n-octyl trimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane, n-dodecyltrimethoxysilane, n-dodecyltriethoxysilane, n-hexadecyltrimethoxysilane, n-hexadecyltriethoxysilane, n- Octadecyltrimethoxysilane, trimethoxy(3,3,3-trifluoropropyl)silane, trimethoxy(pentafluorophenyl)silane, trimethoxy(11-pentafluorophenoxyundecyl)silane, trimethoxy(1H,1H,2H,2H-nona) fluorohexyl)silane, partially hydrolyzed oligomers of tetramethoxysilane (product names: Methyl Silicate 51, Methyl Silicate 53A (manufactured by Colcoat Co., Ltd.)), partially hydrolyzed oligomers of tetraethoxysilane (product names: Ethyl Silicate 40, Examples include Ethyl Silicate 48 (manufactured by Colcoat Co., Ltd.), partially hydrolyzed oligomer of a mixture of tetramethoxysilane and tetraethoxysilane (product name: EMS-485 (manufactured by Colcoat Co., Ltd.)), and the like.

As the silane compound, in addition to the compound represented by the above formula (C1), for example, a compound represented by the following formula (C2) and a compound represented by (C3) can be used in combination.

In the formula, R ^C21 , R ^C22 and R ^C31 each independently represent an alkyl group, and R ^C23 , R ^C24 , R ^C32 , R ^C33 and R ^C34 each independently have a hydrogen atom and a substituent. may be an alkyl group, a phenyl group or a cyclohexyl group, the carbon atoms in the alkyl group may be substituted with an oxygen atom or a nitrogen atom, and m2 represents an integer of 1 or more and 10 or less.

Specific examples of the compound represented by formula (C2) and the compound represented by formula (C3) include dimethyldiethoxysilane, diphenyldimethoxysilane, methylethyldimethoxysilane, and trimethylmethoxysilane. The compounds represented by formula (C1) can be used singly or in combination of two or more. The compound represented by formula (C2) and the compound represented by (C3) can be used alone or in combination with the compound represented by general formula (C1).

The total thickness of the silica layers is preferably 0.5-50 nm, more preferably 1.0-30 nm. A luminescent nanocrystal having such a thickness of silica layer can sufficiently enhance the stability of the nanocrystal against heat and light. The thickness can be measured, for example, with a high-resolution electron microscope.

The total thickness of the silica layer can be changed by adjusting the number of atoms (chain length) of the connecting structure that connects the binding group and the reactive group of the ligand.

From the viewpoint of further improving the external quantum efficiency of the light conversion layer, the content of the luminescent nanocrystalline particles is 0.1 parts by mass or more with respect to the total 100 parts by mass of the components other than the organic solvent contained in the ink composition. , 1 part by mass or more, 5 parts by mass or more, 10 parts by mass or more, 20 parts by mass or more, or 30 parts by mass or more. From the viewpoint of further improving the coating properties, ejection stability, and external quantum efficiency of the light conversion layer, the content of the luminescent nanocrystalline particles is 100 parts by mass in total of the components other than the organic solvent contained in the ink composition. , 80 parts by mass or less, and may be 75 parts by mass or less, 70 parts by mass or less, 60 parts by mass or less, 50 parts by mass or less, or 40 parts by mass or less. In this specification, the term "components other than the organic solvent contained in the ink composition" may also be referred to as components to be contained in the cured product of the ink composition. The “total of components other than the organic solvent contained in the ink composition” includes, for example, luminescent nanocrystalline particles, organic ligands (ligands), photopolymerizable compounds and/or thermosetting resins, and light scattering may be the sum of the physical particles and

From the viewpoint of further improving the external quantum efficiency of the light conversion layer, the content of the luminescent nanocrystalline particles in the ink composition used as the pixel portion of the color filter is It is preferably 5 parts by mass or more, 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, or 30 parts by mass or more with respect to a total of 100 parts by mass. From the viewpoint of further improving the ejection stability and the external quantum efficiency of the pixel portion, the content of the luminescent nanocrystalline particles in the ink composition used as the pixel portion of the color filter is 100% of the components other than the organic solvent. It is preferably 80 parts by mass or less, 75 parts by mass or less, 70 parts by mass or less, or 60 parts by mass or less.

In addition, the content of the luminescent nanocrystalline particles in the ink composition used as the light conversion layer in the sheet-like light conversion film is adjusted from the viewpoint of further improving the external quantum efficiency of the light conversion layer. It is 0.1 parts by mass or more, 0.5 parts by mass or more, 1 part by mass or more, 2 parts by mass or more, or 3 parts by mass or more with respect to the total 100 parts by mass of the components other than the organic solvent contained therein. preferable. The content of the luminescent nanocrystalline particles in the ink composition used as the light conversion layer in the sheet-like light conversion film is the above organic solvent from the viewpoint of further improving the coatability and the external quantum efficiency of the light conversion layer. It is preferably 15 parts by mass or less, 12.5 parts by mass or less, 10 parts by mass or less, 7.5 parts by mass or less, or 5 parts by mass or less with respect to a total of 100 parts by mass of the other components.

When the luminescent nanocrystalline particles contain a metal halide, the content of the luminescent nanocrystalline particles in the ink composition is the same as that of the components other than the organic solvent contained in the ink composition, from the viewpoint of further improving the external quantum efficiency of the light conversion layer. It is preferably 0.1 parts by mass or more, 0.5 parts by mass or more, 1 part by mass or more, or 5 parts by mass or more with respect to a total of 100 parts by mass. The content of the luminescent nanocrystalline particles in the ink composition is 100 mass in total of the components other than the organic solvent contained in the ink composition, from the viewpoint of further improving the coatability, the ejection stability, and the external quantum efficiency of the light conversion layer. It is preferably 30 parts by mass or less, 20 parts by mass or less, 15 parts by mass or less, or 10 parts by mass or less.

The content of the luminescent nanocrystalline particles based on the total mass of the ink composition is 0.1% by mass or more, 0.5% by mass or more, 1% by mass or more, 5% by mass or more, from the viewpoint of further improving the external quantum efficiency. % by mass or more, preferably 10% by mass or more. The content of the luminescent nanocrystalline particles based on the total mass of the ink composition is 36% by mass or less, 34% by mass or less, and 32% by mass, from the viewpoint of improving coatability, ejection stability, and external quantum efficiency. % or less, 30 mass % or less, or 28 mass % or less.

The ink composition may contain, as luminescent nanocrystalline particles, two or more of red luminescent nanocrystalline particles, green luminescent nanocrystalline particles and blue luminescent nanocrystalline particles, but these are preferably used. It may contain only one type of particles. When the ink composition contains red-emitting nanocrystalline particles, the content of green-emitting nanocrystalline particles and the content of blue-emitting nanocrystalline particles are 0 wt% based on the total weight of the luminescent nanocrystalline particles. 50% by mass or less is preferable, 0% by mass or more and 25% by mass or less is more preferable, and 0% by mass or more and 10% by mass or less is particularly preferable. When the ink composition contains green luminescent nanocrystalline particles, the content of red luminescent nanocrystalline particles and the content of blue luminescent nanocrystalline particles are 0 wt% based on the total weight of luminescent nanocrystalline particles. 50% by mass or less is preferable, 0% by mass or more and 25% by mass or less is more preferable, and 0% by mass or more and 10% by mass or less is particularly preferable.

[Photopolymerizable compound]
The photopolymerizable compound is a compound that polymerizes upon irradiation with light, and the photopolymerizable compound may be a photopolymerizable monomer or oligomer. These are used together with a photoinitiator. A photopolymerizable compound may be used individually by 1 type, and may use 2 or more types together.

In the present invention, it is essential to use a (meth)acrylate compound having a (meth)acryloyl group with an acrylic equivalent of 110 or more as the photopolymerizable compound.

The acrylic equivalent is calculated by the following formula.
Acrylic equivalent = molecular weight of (meth)acrylate compound/number of functional groups of (meth)acryloyl group

That is, a (meth)acrylate compound with a large acrylic equivalent has a small proportion of double bonds in the molecule.

By including a (meth)acrylate compound having an acrylic equivalent of 110 or more in the ink composition, curing shrinkage during photocuring is reduced, and adhesion between the substrate and the light conversion layer can be improved.

(Meth)acrylate compounds having an acrylic equivalent of 110 or more include, for example, propyl (meth)acrylate, butyl (meth)acrylate, amyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, dodecyl (meth)acrylate, hexadecyl (meth)acrylate, octadecyl (meth)acrylate, cyclohexyl (meth)acrylate, methoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, nonylphenoxyethyl (meth)acrylate, glycidyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, ethoxyethoxyethyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate Acrylates, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl (meth)acrylate , benzyl (meth)acrylate, phenylbenzyl (meth)acrylate, mono(2-acryloyloxyethyl) succinate, mono(2-methacryloyloxyethyl) succinate, N-[2-(acryloyloxy)ethyl]phthalimide, N -[2-(acryloyloxy)ethyl]tetrahydrophthalimide, 4-hydroxybutyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol diol (Meth)acrylates, tricyclodecanedimethanol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, neopentyl glycol hydroxypivalic acid Ester diacrylate and the like can be mentioned.

The (meth)acrylate compound having an acrylic equivalent of 110 or more is preferably a compound represented by the following formula (I).

[In formula (I), R ¹ represents a hydrogen atom or a methyl group, R ² represents an optionally substituted linear or branched alkylene group having 1 to 20 carbon atoms, m is 1 An integer from ˜10. Two R ^1s may be the same or different. ]

Preferable examples of (meth)acrylate compounds having an acrylic equivalent of 110 or more include 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, propylene glycol di(meth)acrylate, (Meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate and the like.

In the photopolymerizable compound, the content of the (meth)(meth)acrylate compound having an acrylic equivalent of 110 or more is 5% by mass or more based on the total mass of the photopolymerizable compound, from the viewpoint of obtaining sufficient curability. , 10% by mass or more, or 20% by mass or more, and from the viewpoint of making the viscosity of the ink composition low, it may be 90% by mass or less, 80% by mass or less, or 70% by mass or less.

The photopolymerizable compound other than the (meth)acrylate compound having an acrylic equivalent of 110 or more is not particularly limited, and known compounds can be used.
For example, monofunctional (meth)acrylate compounds include methyl, ethyl, propyl, butyl, amyl, 2-ethylhexyl, octyl, nonyl, decyl, lauryl, hexadecyl, stearyl, cyclohexyl, benzyl, methoxyethyl, butoxyethyl, phenoxyethyl. , nonylphenoxyethyl, glycidyl, dimethylaminoethyl, diethylaminoethyl, isobornyl, dicyclopentanyl, dicyclopentenyl, dicyclopentenyloxyethyl, tetrahydrofurfuryl, ethoxylated terorahydrofuran (meth) Acrylates are mentioned. Polyfunctional (meth)acrylates include di(meth)acrylates such as tricyclodecanedimethanol, polyethylene glycol, tripropylene glycol and polypropylene glycol; a di(meth)acrylate of a diol obtained by adding 2 mol of ethylene oxide or propylene oxide to 1 mol of bisphenol A, 3 mol or more of ethylene oxide per 1 mol of trimethylolpropane, or Di or tri(meth)acrylate of triol obtained by adding propylene oxide, di(meth)acrylate of diol obtained by adding 4 mol or more of ethylene oxide or propylene oxide to 1 mol of bisphenol A, poly of dipentaerythritol (Meth)acrylates, ethylene oxide-modified phosphate (meth)acrylates, ethylene oxide-modified alkyl phosphate (meth)acrylates, and the like.

Polymerizable oligomers such as (meth)acrylate oligomers can also be used. Polymerizable oligomers include polyurethane (meth)acrylate, polyester (meth)acrylate, polyacrylic (meth)acrylate, epoxy (meth)acrylate, polyalkylene glycol poly(meth)acrylate, polyether (meth)acrylate, and the like. , can be used in combination of two or more.

Further, as the photopolymerizable compound in the present embodiment, the photopolymerizable compounds described in paragraphs 0042 to 0049 of JP-A-2013-182215 can also be used.

In the present embodiment, the photopolymerizable compound preferably contains a monofunctional (meth)acrylate compound.

The monofunctional (meth)acrylate compound is not particularly limited, and a known compound can be used, preferably a monofunctional (meth)acrylate compound containing a cyclic structure.

The monofunctional (meth)acrylate compound containing a cyclic structure is preferably a monofunctional methacrylate compound containing an aliphatic polycyclic structure from the viewpoint of the height of the glass transition point of the resulting resin. Specifically, isobornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentanyl (meth)acrylate and the like.

When a monofunctional (meth)acrylate compound is included as the photopolymerizable compound, the content of the monofunctional (meth)acrylate compound in the photopolymerizable compound is adjusted from the viewpoint of making the viscosity of the ink composition low. Based on the total mass of the chemical compound, it may be 5% by mass or more, 10% by mass or more, or 20% by mass or more, and from the viewpoint of suppressing tackiness, it is 90% by mass or less, 80% by mass or less, or 70% by mass or less. It's okay.
As the photopolymerizable compound, a monomer having an ethylenically unsaturated group other than the "(meth)acryloyl group" and the "acryloyl group", a monomer having an isocyanate group, and the like can be optionally used. Examples of ethylenically unsaturated groups other than "(meth)acryloyl group" and "acryloyl group" include vinyl group, vinylene group, and vinylidene group.
Examples of the vinyl ether compound, which is a monomer having an ethylenically unsaturated group having a vinyl group, include 2-(2-vinyloxyethoxy)ethyl acrylate, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether. Polymerizable compounds having a vinyl ether group such as vinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether, cyclohexanedimethanol divinyl ether, trimethylolpropane trivinyl ether, and other di- or trivinyl ether compounds. Examples of the allyl ether compound, which is a monomer having an ethylenically unsaturated group having a vinyl group, include methyl 2-(allyloxymethyl)acrylate, diallyl phthalate, 1,3-diallyloxy-2-propanol, and pentaerythritol tetraallyl. Examples include polymerizable compounds having an allyl ether group such as ethers.

Optionally, a (meth)acrylamide compound can also be used as the photopolymerizable compound.
Optionally, a photo-cationically polymerizable compound can also be used as the photopolymerizable compound. A photocationically polymerizable compound is used together with a photocationic polymerization initiator.
Examples of photo-cationically polymerizable compounds include epoxy compounds, oxetane compounds, and vinyl ether compounds.

Examples of epoxy compounds include aliphatic epoxy compounds such as bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, phenol novolac type epoxy compounds, trimethylolpropane polyglycidyl ether, neopentyl glycol diglycidyl ether, 1,2-epoxy- Alicyclic epoxy compounds such as 4-vinylcyclohexane, 1-methyl-4-(2-methyloxiranyl)-7-oxabicyclo[4.1.0]heptane, and the like.

It is also possible to use a commercially available product as the epoxy compound. Commercially available epoxy compounds include, for example, “Celoxide 2000”, “Celoxide 3000” and “Celoxide 4000” manufactured by Daicel Chemical Industries, Ltd.

Examples of cationic polymerizable oxetane compounds include 2-ethylhexyloxetane, 3-hydroxymethyl-3-methyloxetane, 3-hydroxymethyl-3-ethyloxetane, 3-hydroxymethyl-3-propyloxetane, 3-hydroxymethyl-3 -N-butyloxetane, 3-hydroxymethyl-3-phenyloxetane, 3-hydroxymethyl-3-benzyloxetane, 3-hydroxyethyl-3-methyloxetane, 3-hydroxyethyl-3-ethyloxetane, 3-hydroxyethyl- 3-propyloxetane, 3-hydroxyethyl-3-phenyloxetane, 3-hydroxypropyl-3-methyloxetane, 3-hydroxypropyl-3-ethyloxetane, 3-hydroxypropyl-3-propyloxetane, 3-hydroxypropyl- 3-phenyloxetane, 3-hydroxybutyl-3-methyloxetane and the like.

A commercially available product can also be used as the oxetane compound. Commercially available oxetane compounds include, for example, the Aron oxetane series manufactured by Toagosei Co., Ltd. ("OXT-101", "OXT-212", "OXT-121", "OXT-221", etc.); Daicel Chemical Industries, Ltd. "Celoxide 2021", "Celoxide 2021A", "Celoxide 2021P", "Celoxide 2080", "Celoxide 2081", "Celoxide 2083", "Celoxide 2085", "Epolead GT300", "Epolead GT301", "Epolead" manufactured by the company GT302", "Epolead GT400", "Epolead GT401" and "Epolead GT403"; "Cyracure UVR-6105", "Cyracure UVR-6107", "Cyracure UVR-6110", "Cyracure UVR" manufactured by Dow Chemical Japan Co., Ltd. -6128”, “ERL4289” and “ERL4299” can be used. In addition, known oxetane compounds (eg, oxetane compounds described in JP-A-2009-40830, etc.) can also be used.

Examples of vinyl ether compounds include 2-(2-vinyloxyethoxy)ethyl acrylate, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether. , hexanediol divinyl ether, cyclohexanedimethanol divinyl ether, trimethylolpropane trivinyl ether, and other di- or trivinyl ether compounds having a vinyl ether group.

The photopolymerizable compound may be alkali-insoluble from the viewpoint of easily obtaining a highly reliable pixel portion (cured product of the ink composition). In the present specification, the photopolymerizable compound being alkali-insoluble means that the amount of the photopolymerizable compound dissolved in a 1% by mass aqueous potassium hydroxide solution at 25° C. is 30, based on the total mass of the photopolymerizable compound. % or less. The dissolved amount of the photopolymerizable compound is preferably 10% by mass or less, more preferably 3% by mass or less.

The content of the photopolymerizable compound is determined from the viewpoint of easily obtaining an appropriate viscosity as an inkjet ink, the viewpoint of good curability of the ink composition, and the solvent resistance and From the viewpoint of improving abrasion resistance, it may be 10 parts by mass or more, or may be 15 parts by mass or more, with respect to a total of 100 parts by mass of components other than the organic solvent contained in the ink composition. 20 mass parts or more may be sufficient. The content of the photopolymerizable compound is, from the viewpoint of easily obtaining an appropriate viscosity as an inkjet ink and from the viewpoint of obtaining better optical properties (e.g., external quantum efficiency), the content of the photopolymerizable compound other than the organic solvent contained in the ink composition. With respect to a total of 100 parts by mass of the components, it may be 60 parts by mass or less, may be 50 parts by mass or less, may be 40 parts by mass or less, may be 30 parts by mass or less, or may be 20 parts by mass or less. It may be less than or equal to parts by mass.

[Photoinitiator]
The photopolymerization initiator is, for example, a photoradical polymerization initiator or a photocationic polymerization initiator. As the photoradical polymerization initiator, a molecular cleavage type or hydrogen abstraction type photoradical polymerization initiator is suitable.

Molecular cleavage type photoradical polymerization initiators include benzoin isobutyl ether, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and 2-benzyl-2-dimethylamino-1. -(4-morpholinophenyl)-butan-1-one, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, (2,4,6-trimethylbenzoyl)ethoxyphenylphosphine oxide etc. are preferably used. Other molecular cleavage type radical photopolymerization initiators include 1-hydroxycyclohexylphenyl ketone, benzoin ethyl ether, benzyl dimethyl ketal, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4 -isopropylphenyl)-2-hydroxy-2-methylpropan-1-one and 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one may be used in combination.

Benzophenone, 4-phenylbenzophenone, isophthalphenone, 4-benzoyl-4'-methyl-diphenyl sulfide and the like are examples of hydrogen abstraction type photoradical polymerization initiators. A molecular cleavage type radical photopolymerization initiator and a hydrogen abstraction type photoradical polymerization initiator may be used in combination.

A commercial product can also be used as a photocationic polymerization initiator. Commercially available products include sulfonium salt photocationic polymerization initiators such as "CPI-100P" manufactured by San-Apro, acylphosphine oxide compounds such as "Lucirin TPO" manufactured by BASF, "Irgacure 907" manufactured by BASF, "Irgacure 819", "Irgacure 379EG", "Irgacure 184" and "Irgacure PAG290".

From the viewpoint of curability of the ink composition, the content of the photopolymerization initiator may be 0.1 parts by mass or more, or 0.5 parts by mass or more with respect to 100 parts by mass of the photopolymerizable compound. It may be 1 part by mass or more, 3 parts by mass or more, or 5 parts by mass or more. The content of the photopolymerization initiator may be 40 parts by mass or less, or 30 parts by mass with respect to 100 parts by mass of the photopolymerizable compound, from the viewpoint of the temporal stability of the pixel portion (cured product of the ink composition). or less, 20 parts by mass or less, or 10 parts by mass or less.

[Metal compound having a dithiocarbamic acid group]
The metal compound having a dithiocarbamic acid group of this embodiment is a compound in which a dithiocarbamic acid group is coordinated to a metal atom, and is represented by the following formula (II).

[In formula (II), R ³ and R ⁴ ^each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms and may be linked to each other via a hydrocarbon group; and ^R4 may be the same or different, M represents a metal atom, and n represents an integer of 1-4. ]

The number of dithiocarbamic acid groups coordinating to the metal atom is equal to the valence of the metal atom. For example, if the metal atom is zinc, the zinc atom is a divalent metal, so two dithiocarbamate groups are coordinated to the zinc. The sulfur atom is coordinated to the zinc atom by direct bonding (eg, ionic bond) to the zinc atom. The two ligands may be the same or different from each other.

The metal atom preferably includes zinc atom, sodium atom, copper atom and tellurium atom, more preferably zinc atom, sodium atom and copper atom, and particularly preferably zinc atom.

The number of carbon atoms in the hydrocarbon group may be 1-6, or 1-4. The hydrocarbon group may be an alkyl group, an aryl group, an aralkyl group, etc., preferably an alkyl group. Alkyl groups may be straight or branched. Examples of alkyl groups include methyl, ethyl, propyl, butyl, pentyl, and hexyl groups. Although the combination of R ³ and R ⁴ is not particularly limited, all of R ³ and R ⁴ are preferably hydrocarbon groups, and more preferably all of R ³ and R ⁴ are alkyl groups.

The molecular weight of the metal compound having a dithiocarbamic acid group is, for example, 700 or less. When the molecular weight is 700 or less, there is a tendency to be more excellent in thermal stability and light stability. The molecular weight of the metal compound having a dithiocarbamic acid group may be 600 or less or 500 or less. The molecular weight of the metal compound having a dithiocarbamic acid group may be 200 or more from the viewpoint of easily increasing the solubility in the ink composition.

In formula (II), the ligand may be monodentate or bidentate to the metal atom. That is, compounds represented by formula (II) include compounds represented by the following formulas (II-1) to (II-3) when the metal atom is zinc.

As the metal compound having a dithiocarbamic acid group, it is possible to use commercially available products, and commercially available products include Noxcellar PZ, Noxcella EZ, Noxcella BZ-P, Noxcella PX, Noxcella ZP, Noxcella ZTC, Noxcella TP, and Noxcella. TTCU, Noxeler TTTE, etc. can be used.

From the viewpoint of further improving the stability to heat and excitation light, the content of the metal compound having a dithiocarbamic acid group is 0.1 mass parts per 100 mass parts in total of the components other than the organic solvent contained in the ink composition. It may be 1 part or more, 1 part by mass or more, or 2 parts by mass or more. From the viewpoint of solubility, the content of the metal compound having a dithiocarbamic acid group may be 20 parts by mass or less, or 10 parts by mass, with respect to the total 100 parts by mass of the components other than the organic solvent contained in the ink composition. It may be less than or equal to 7 parts by mass or less.

[Antioxidant]
The ink composition may further contain an antioxidant. As the antioxidant, conventionally known antioxidants such as phenol antioxidants, amine antioxidants, phosphorus antioxidants, and thiol antioxidants can be used. Among these, it is preferable to use a phenol-based antioxidant and a phosphorus-based antioxidant. You may use antioxidant individually by 1 type or in combination of 2 or more types. For example, a phosphorus antioxidant and a phenolic antioxidant may be used in combination.

From the viewpoint of further improving the stability against heat and excitation light, the content of the antioxidant is 0.1 parts by mass or more with respect to the total 100 parts by mass of the components other than the organic solvent contained in the ink composition. may be 1 part by mass or more, or 3 parts by mass or more. From the viewpoint of solubility, the content of the antioxidant may be 20 parts by mass or less, or 10 parts by mass or less, with respect to the total 100 parts by mass of the components other than the organic solvent contained in the ink composition. It may be 7 parts by mass or less.

[Phenolic inhibitor]
Phenolic antioxidants include, for example, 2,4,6-tris(3′,5′-di-t-butyl-4′-hydroxybenzyl)mesitylene (product name: AO-330), 2,4- Bis-(n-octylthio)-6-(4-hydroxy-3,5-di-t-butylanilino)-1,3,5-triazine (product name: Irganox565), pentaerythritol tetrakis[3-(3,5 -di-t-butyl-4-hydroxyphenyl)propionate (product name: AO-60), octadecyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate (product name: AO-50) , 2,6-di-t-butyl-4-nonylphenol, thiodiethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2′-methylenebis-(6- (1-methylcyclohexyl)-p-cresol), N,N-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide) (product name: Irganox 1098), 2,5- Di-t-butylhydroquinone, 2,5-di-t-amyl-hydroquinone, 2,4-dimethyl-6-(1-methylcyclohexyl)-phenol, 6-t-butyl-o-cresol, 6-t- Butyl-2,4-xylenol, 2,4-dimethyl-6-(1-methylpentadecyl)phenol, 2,4-bis(octylthiomethyl)-o-cresol (product name: Irganox 1520), 2,4- Bis(dodecylthiomethyl)-o-cresol, ethylenebis(oxyethylene)bis[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate], 3,9-bis[2-[3 -(t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane (product name: AO- 80), triethylene glycol bis[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate (product name: Irganox245), 2-t-amylphenol, 2-t-butylphenol, 2,4 -di-t-butylphenol, 1,1,3-tris-(2'-methyl-4'-hydroxy-5'-t-butylphenyl)-butane (product name: AO-30), 4,4'- butylidene-bis-(2-t-butyl-5-methylphenol) and the like. can be

Phenolic antioxidants are hindered phenol antioxidants in which the hydrogen atoms at both ortho-positions of the phenolic hydroxyl group are substituted with sterically bulky groups. A semi-hindered phenolic antioxidant substituted with a sterically bulky group and the other ortho-position hydrogen atom substituted with a methyl group, and one ortho-position hydrogen atom of the phenolic hydroxyl group is steric It may be any hindered phenolic antioxidant that is substituted with a bulky group and the other hydrogen atom at the ortho position is unsubstituted. A sterically bulky group means a branched alkyl group other than a linear alkyl group or an aromatic ring group. Specifically, tertiary alkyl groups such as t-butyl group, t-pentyl group and t-hexyl group; secondary alkyl groups such as i-propyl group, sec-butyl group and sec-pentyl group; i-butyl cycloalkyl groups such as cyclohexyl group and cyclopentyl group; and aromatic ring groups such as phenyl group, benzyl group and naphthyl group.

The phenolic antioxidant is preferably a hindered phenolic antioxidant. Hindered phenol antioxidants include, for example, 2,4,6-tris(3′,5′-di-t-butyl-4′-hydroxybenzyl)mesitylene, 2,4-bis-(n-octylthio )-6-(4-hydroxy-3,5-di-t-butylanilino)-1,3,5-triazine, pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl) Propionate, octadecyl 3-(3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2,6-di-t-butyl-4-nonylphenol, thiodiethylenebis[3-(3,5-di- t-butyl-4-hydroxyphenyl)propionate], N,N-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), etc. Among these, pentaerythritol Tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate is preferably used.

Commercially available phenolic antioxidants include antioxidants manufactured by ADEKA Co., Ltd., ADEKA STAB AO-20, ADEKA STAB AO-30, ADEKA STAB AO-40, ADEKA STAB AO-50, ADEKA STAB AO-60, ADEKA STAB AO- ６０Ｇ、アデカスタブＡＯ－７０、アデカスタブＡＯ－８０、アデカスタブＡＯ－３３０等、ＢＡＳＦ社製の酸化防止剤である、Ｉｒｇａｎｏｘ１０１０、Ｉｒｇａｎｏｘ１０１０ＦＦ、Ｉｒｇａｎｏｘ１０３５、Ｉｒｇａｎｏｘ１０３５ＦＦ（Ｗ＆Ｃ）、Ｉｒｇａｎｏｘ１０７６、Ｉｒｇａｎｏｘ１０７６ＦＤ、Ｉｒｇａｎｏｘ１０９８、Ｉｒｇａｎｏｘ１１３５、Ｉｒｇａｎｏｘ１３３０、Ｉｒｇａｎｏｘ１５２０Ｌ , Irganox 245, Irganox 245FF, Irganox 259, Irganox 3114, etc., SUMILIZER GP, SUMILIZER GS (F), SUMILIZER GM (F), SUMILIZER GA-80, SUMILIZER MDP-S, SUMILIZER MDP-I, which are antioxidants manufactured by Sumitomo Chemical Co., Ltd. R, SUMILIZER WX-RC and the like.

[Phosphorus antioxidant]
The phosphorus antioxidant may be a compound represented by the following formula (III).

[In Formula (2), R ⁵ , R ⁶ and R ⁷ each independently represent a monovalent organic group. Two kinds selected from R ⁵ , R ⁶ and R ⁷ may combine with each other to form a ring. ]

The monovalent organic group fully satisfies the performance requirements specific to inkjet inks, such as compatibility with other components (photopolymerizable compounds, etc.) in inkjet inks, and further suppresses the decrease in fluorescence quantum yield of inkjet inks. It is preferably a monovalent hydrocarbon group from the viewpoint of being able to. Examples of monovalent hydrocarbon groups include alkyl groups, aryl groups, and alkenyl groups. The number of carbon atoms in the monovalent hydrocarbon group may be 1 to 30, and may be 4 to 18 from the viewpoint of solubility.

The alkyl group may be linear or branched. Examples of alkyl groups include 2-ethylhexyl, butyl, octyl, nonyl, decyl, isodecyl, dodecyl, hexadecyl and octadecyl groups.

Examples of the aryl group include a phenyl group, a naphthyl group, a tert-butylphenyl group, a di-tert-butylphenyl group, an octylphenyl group, a nonylphenyl group, an isodecylphenyl group, an isodecylphenyl group and an isodecylnaphthyl group. mentioned.

The monovalent hydrocarbon group is preferably an alkyl group or an aryl group, more preferably an alkyl group or a phenyl group, from the viewpoint of further suppressing a decrease in fluorescence quantum yield.

The phosphorus antioxidant is preferably a compound represented by the following formula (IV).

[In formula (IV), R ⁸ and R ⁹ each independently represent an alkyl group or an aryl group, and R ⁸ and R ⁹ may be the same or different. ]

Specific examples of the compound represented by formula (IV) include cyclic neopentanetetraylbis(octadecylphosphite), pentaerythritolbis(2,4-di-tert-butylphenylphosphite), (2, 6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, diisodecylpentaerythritol diphosphite and the like.

Phosphorus-based antioxidants may be liquid or solid at room temperature (25° C.), but are preferably compatible with other components (photopolymerizable compounds, etc.) in the inkjet ink. It is a liquid at room temperature (25° C.) from the viewpoint of sufficiently satisfying the required performance specific to the ink and further suppressing the decrease in fluorescence quantum yield of the ink jet ink. The melting point of the phosphorus antioxidant may be 20°C or lower, or 10°C or lower.

[Light scattering particles]
The ink composition may further contain light scattering particles. Light-scattering particles are, for example, optically inactive inorganic fine particles. When the ink composition contains light-scattering particles, it is possible to scatter the light emitted from the light source with which the pixel portion is irradiated, so excellent optical properties (for example, external quantum efficiency) can be obtained.

Materials constituting the light-scattering particles include, for example, simple metals such as tungsten, zirconium, titanium, platinum, bismuth, rhodium, palladium, silver, tin, platinum, and gold; silica, barium sulfate, barium carbonate, calcium carbonate, Metal oxides such as talc, clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, alumina white, titanium oxide, magnesium oxide, barium oxide, aluminum oxide, bismuth oxide, zirconium oxide, zinc oxide; magnesium carbonate, barium carbonate, Metal carbonates such as bismuth subcarbonate and calcium carbonate; Metal hydroxides such as aluminum hydroxide; Composite oxides such as barium zirconate, calcium zirconate, calcium titanate, barium titanate and strontium titanate, bismuth subnitrate metal salts such as The light-scattering particles include titanium oxide, alumina, zirconium oxide, zinc oxide, calcium carbonate, barium sulfate, and titanium oxide, from the viewpoint of excellent dispersion stability and ejection stability of the ink composition and from the viewpoint of improving the external quantum efficiency. It preferably contains at least one selected from the group consisting of barium oxide and silica, and more preferably contains at least one selected from the group consisting of titanium oxide, zirconium oxide, zinc oxide and barium titanate.

The shape of the light-scattering particles may be spherical, filamentous, amorphous, or the like. However, as the light-scattering particles, the use of particles having a less directional particle shape (e.g., spherical, regular tetrahedral particles, etc.) improves the uniformity, fluidity, and light-scattering properties of the ink composition. It is preferable in that it can be improved and excellent dispersion stability and ejection stability can be obtained.

The average particle diameter (volume average diameter) of the light-scattering particles in the ink composition is 0.05 μm (50 nm) or more from the viewpoint of excellent dispersion stability and ejection stability and from the viewpoint of improving the external quantum efficiency. , 0.2 μm (200 nm) or more, or 0.3 μm (300 nm) or more. The average particle diameter (volume average diameter) of the light-scattering particles in the ink composition may be 1.0 μm (1000 nm) or less, or 0.6 μm ( 600 nm) or less, or 0.4 μm (400 nm) or less. The average particle diameter (volume average diameter) of the light scattering particles in the ink composition is 0.05 to 1.0 μm, 0.05 to 0.6 μm, 0.05 to 0.4 μm, 0.2 to 1 0.0 μm, 0.2-0.6 μm, 0.2-0.4 μm, 0.3-1.0 μm, 0.3-0.6 μm, or 0.3-0.4 μm. From the viewpoint of easily obtaining such an average particle diameter (volume average diameter), the average particle diameter (volume average diameter) of the light-scattering particles used may be 0.05 μm or more and 1.0 μm or less. may In this specification, the average particle diameter (volume average diameter) of the light scattering particles in the ink composition is obtained by measuring with a dynamic light scattering Nanotrack particle size distribution meter and calculating the volume average diameter. . The average particle size (volume average size) of the light-scattering particles to be used can be obtained by measuring the particle size of each particle with, for example, a transmission electron microscope or scanning electron microscope and calculating the volume average size.

From the viewpoint of improving the external quantum efficiency of the light conversion layer, the content of the light-scattering particles in the ink composition is 0.00 parts per 100 parts by mass of the components other than the organic solvent contained in the ink composition. It may be 1 part by mass or more, 1 part by mass or more, or 3 parts by mass or more. The content of the light-scattering particles is 100 mass in total of the components other than the organic solvent contained in the ink composition, from the viewpoint of excellent dispersion stability and ejection stability, and from the viewpoint of improving the external quantum efficiency of the light conversion layer. parts, may be 60 parts by mass or less, may be 50 parts by mass or less, may be 40 parts by mass or less, may be 30 parts by mass or less, or may be 25 parts by mass or less. may be 20 parts by mass or less, or may be 15 parts by mass or less.

The content of the light-scattering particles based on the total mass of the ink composition is preferably 3% by mass or more, 4% by mass or more, or 7% by mass, from the viewpoint of further improving the external quantum efficiency of the light conversion layer. or more. The content of the light-scattering particles based on the total mass of the ink composition is preferably 20% by mass or less from the viewpoint of further improving the external quantum efficiency of the pixel portion and further improving the ejection stability. , 18% by mass or less, or 15% by mass or less.

The mass ratio of the content of the light-scattering particles to the content of the luminescent nanocrystalline particles (light-scattering particles/luminescent nanocrystalline particles) is 0.5 from the viewpoint of improving the external quantum efficiency of the light conversion layer. It may be 1 or more, 0.2 or more, or 0.5 or more. The mass ratio (light-scattering particles/luminescent nanocrystalline particles) is 5.0 from the viewpoint of excellent effect of improving the external quantum efficiency of the light conversion layer, and particularly excellent continuous ejection property (ejection stability) during inkjet printing. It may be less than or equal to 2.0, or less than or equal to 1.5.

The total amount of the luminescent nanocrystalline particles and the light-scattering particles in the ink composition is 100 parts by mass in total of the components other than the organic solvent contained in the ink composition, from the viewpoint of easily obtaining an appropriate viscosity as an inkjet ink. , preferably 20 parts by mass or more, more preferably 25 parts by mass or more, and still more preferably 30 parts by mass or more. The total amount of the luminescent nanocrystalline particles and the light-scattering particles in the ink composition is 100 parts by mass in total of the components other than the organic solvent contained in the ink composition, from the viewpoint of easily obtaining an appropriate viscosity as an inkjet ink. , preferably 75 parts by mass or less, more preferably 65 parts by mass or less, and even more preferably 55 parts by mass or less.

[Polymer dispersant]
The ink composition may further contain a polymeric dispersant. A polymeric dispersant is a polymeric compound having a weight average molecular weight of 750 or more and having a functional group having an affinity for light scattering particles. The polymer dispersant has a function of dispersing the light scattering particles. The polymer dispersant adsorbs to the light-scattering particles via a functional group having affinity for the light-scattering particles, and the light-scattering particles are dispersed by electrostatic repulsion and/or steric repulsion between the polymer dispersants. Disperse in the ink composition. When the ink composition contains a polymer dispersant, even when the content of the light-scattering particles is relatively large (for example, about 60% by mass), the light-scattering particles can be dispersed satisfactorily. can. The polymer dispersant is preferably bound to the surface of the light-scattering particles and adsorbed to the light-scattering particles. may be free in the ink composition.

Functional groups that have affinity for light-scattering particles include acidic functional groups, basic functional groups, and nonionic functional groups. Acidic functional groups have dissociative protons and may be neutralized with bases such as amines and hydroxide ions, while basic functional groups are neutralized with acids such as organic acids and inorganic acids. may

Examples of acidic functional groups include carboxyl group (--COOH), sulfo group (--SO ₃ H), sulfate group (--OSO ₃ H), phosphonic acid group (--PO(OH) ₃ ), phosphoric acid group (--OPO ( OH) ₃ ), phosphinic acid group (--PO(OH)--), mercapto group (--SH).

Basic functional groups include primary, secondary and tertiary amino groups, ammonium groups, imino groups, and nitrogen-containing heterocyclic groups such as pyridine, pyrimidine, pyrazine, imidazole and triazole.

Nonionic functional groups include hydroxy group, ether group, thioether group, sulfinyl group (-SO-), sulfonyl group ( _-SO2- ), carbonyl group, formyl group, ester group, carbonate group, amide group, Carbamoyl group, ureido group, thioamide group, thioureido group, sulfamoyl group, cyano group, alkenyl group, alkynyl group, phosphine oxide group and phosphine sulfide group.

The polymeric dispersant may be a polymer (homopolymer) of a single monomer, or a copolymer (copolymer) of a plurality of types of monomers. Further, the polymeric dispersant may be any of random copolymers, block copolymers and graft copolymers. When the polymeric dispersant is a graft copolymer, it may be a comb-shaped graft copolymer or a star-shaped graft copolymer. Examples of polymer dispersants include acrylic resins, polyester resins, polyurethane resins, polyamide resins, polyethers, phenol resins, silicone resins, polyurea resins, amino resins, epoxy resins, polyamines such as polyethyleneimine and polyallylamine, and polyimides. It's okay.

Commercially available products can be used as the polymer dispersant, and commercial products include Ajinomoto Fine-Techno Co., Inc.'s Ajisper PB series, BYK's DISPERBYK series and BYK-series, and BASF's Efka series. etc. can be used.

[Organic solvent]
The ink composition may further contain an organic solvent. Examples of organic solvents include ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol dibutyl ether, diethyl adipate, dibutyl oxalate, dimethyl malonate, diethyl malonate, dimethyl succinate, and succinic acid. diethyl, 1,4-butanediol diacetate, glyceryl triacetate and the like.

When used for inkjet ink, the boiling point of the organic solvent is preferably 150°C or higher, more preferably 180°C or higher, from the viewpoint of continuous ejection stability. Further, since the solvent must be removed from the ink composition before it is cured when forming the pixel portion, the boiling point of the organic solvent is preferably 300° C. or less from the viewpoint of easy removal of the organic solvent.

The organic solvent preferably contains an acetate compound with a boiling point of 150°C or higher. In this case, the affinity between the luminescent nanocrystalline particles and the solvent is improved, and the luminescent nanocrystalline particles can exhibit excellent luminous properties. Specific examples of acetate compounds having a boiling point of 150° C. or higher include monoacetate compounds such as diethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, and dipropylene glycol methyl ether acetate, and 1,4-butanediol diol. Acetate, diacetate compounds such as propylene glycol diacetate, triacetate compounds such as glycerol triacetate, and the like.

In the ink composition of the present embodiment, since the photopolymerizable compound also functions as a dispersion medium, it is possible to disperse the light-scattering particles and the luminescent nanocrystalline particles without a solvent. In this case, there is an advantage that the step of removing the solvent by drying is not required when forming the pixel portion.

The viscosity of the ink composition described above at the ink temperature during inkjet printing may be, for example, 2 mPa·s or more, 5 mPa·s or more, or 7 mPa from the viewpoint of ejection stability during inkjet printing. * It may be s or more. The viscosity of the ink composition at the ink temperature during inkjet printing may be 20 mPa·s or less, 15 mPa·s or less, or 12 mPa·s or less. The viscosity of the ink composition at the ink temperature during inkjet printing is, for example, 2 to 20 mPa·s, 2 to 15 mPa·s, 2 to 12 mPa·s, 5 to 20 mPa·s, 5 to 15 mPa·s, and 5 to 12 mPa·s. s, 7 to 20 mPa·s, 7 to 15 mPa·s, or 7 to 12 mPa·s. In this specification, the viscosity of the ink composition is measured at 25° C., for example, by an E-type viscometer.

When the viscosity of the ink composition at the ink temperature during inkjet printing is 2 mPa s or more, the meniscus shape of the inkjet ink at the tip of the ink ejection hole of the ejection head is stabilized. control of the amount and timing of ejection) becomes easier. On the other hand, when the viscosity of the ink composition at the ink temperature during inkjet printing is 20 mPa·s or less, the inkjet ink can be smoothly ejected from the ink ejection holes.

The surface tension of the ink composition is preferably a surface tension suitable for an inkjet system, specifically preferably in the range of 20 to 40 mN/m, more preferably 25 to 35 mN/m. . By setting the surface tension within this range, it is possible to facilitate ejection control (for example, control of ejection amount and ejection timing) and to suppress the occurrence of flight deflection. The term "flight deflection" means that when the ink composition is ejected from the ink ejection holes, the landing position of the ink composition deviates from the target position by 30 μm or more. When the surface tension is 40 mN/m or less, the meniscus shape at the tip of the ink ejection hole is stabilized, so that the ejection control of the ink composition (for example, control of ejection amount and ejection timing) becomes easy. On the other hand, when the surface tension is 20 mN/m or more, contamination of the periphery of the ink ejection holes with the ink jet ink can be prevented, so that the occurrence of flight deflection can be suppressed. That is, the ink composition is not accurately deposited on the pixel portion forming region where the ink composition should be deposited, resulting in an insufficiently filled pixel portion, or the pixel portion forming region (or pixel portion) adjacent to the pixel portion forming region where the ink composition should be deposited. The ink composition does not land on the surface, and the color reproducibility is not deteriorated. The surface tension described in the specification of the present application refers to the surface tension measured at 23° C., which is measured by the ring method (also referred to as the ring method).

When the ink composition of the present embodiment is used as an ink composition for an ink jet system, it is preferably applied to a piezo jet ink jet recording apparatus with a mechanical ejection mechanism using a piezoelectric element. In the piezo jet method, the ink composition is not instantaneously exposed to high temperatures during ejection. Therefore, the luminescent nanocrystalline particles are less likely to be degraded, and expected luminous properties can be more easily obtained in the pixel portion (light conversion layer).

Although one embodiment of the inkjet ink composition has been described above, the inkjet ink composition of the embodiment described above can also be used in, for example, a photolithography method in addition to the inkjet method. In this case, the ink composition contains an alkali-soluble resin as a binder polymer.

When the ink composition is used in the photolithography method, first, the ink composition is applied onto a substrate, and the ink composition is dried to form a coating film. The coating film thus obtained is soluble in an alkaline developer, and is patterned by being treated with an alkaline developer. At this time, the alkali developer is mostly an aqueous solution from the viewpoint of ease of disposal of the waste liquid of the developer, and therefore the coating film of the ink composition is treated with an aqueous solution. On the other hand, in the case of an ink composition using luminescent nanocrystalline particles (quantum dots, etc.), the luminescent nanocrystalline particles are unstable against water, and luminescence (for example, fluorescence) is impaired by moisture. For this reason, in the present embodiment, the ink jet method is preferable because it does not require treatment with an alkaline developer (aqueous solution).

In addition, even when the coating film of the ink composition is not treated with an alkaline developer, if the ink composition is alkali-soluble, the coating film of the ink composition easily absorbs moisture in the atmosphere. Luminescent properties (for example, fluorescence) of luminescent nanocrystalline particles (quantum dots, etc.) deteriorate over time. From this point of view, in the present embodiment, the coating film of the ink composition is preferably alkali-insoluble. That is, the ink composition of the present embodiment is preferably an ink composition capable of forming an alkali-insoluble coating film. Such an ink composition can be obtained by using an alkali-insoluble photopolymerizable compound and a thermosetting resin as the photopolymerizable compound and the thermosetting resin. The fact that the coating film of the ink composition is alkali-insoluble means that the amount of the coating film of the ink composition dissolved in a 1% by mass aqueous potassium hydroxide solution at 25° C. is, based on the total mass of the coating film of the ink composition, It means that it is 30% by mass or less. The amount of the ink composition dissolved in the coating film is preferably 10% by mass or less, and more preferably 3% by mass or less. It should be noted that the fact that the ink composition is an ink composition capable of forming an alkali-insoluble coating film means that the thickness obtained by applying the ink composition on a substrate and then drying it under the conditions of 80° C. for 3 minutes It can be confirmed by measuring the amount of dissolution of the coating film of 1 μm.

<Method for producing ink composition>
The ink composition of the present embodiment includes, for example, the above-described components (luminescent nanocrystalline particles (e.g., organic ligand-modified luminescent nanocrystalline particles), photopolymerizable compounds, hindered amine compounds, and other optional component).
The method for producing the ink composition may further include a step of dispersing the mixture of the above components.
As an example, a method for producing an ink composition containing light-scattering particles will be described below.

A method for producing an ink composition containing light-scattering particles includes, for example, a first step of preparing a dispersion of light-scattering particles, and a second step of mixing the dispersion of light-scattering particles and luminescent nanocrystalline particles. 2 steps.
The dispersion of light scattering particles may further contain a polymeric dispersant. In this method, the dispersion of light-scattering particles may further contain a photopolymerizable compound, and the photopolymerizable compound may be further mixed in the second step.
According to the above method, the light-scattering particles can be sufficiently dispersed. Therefore, it is possible to improve the optical properties (for example, external quantum efficiency) of the pixel portion, and to easily obtain an ink composition having excellent ejection stability.

In the first step, light-scattering particles may be mixed with, if necessary, a polymer dispersant, and a photopolymerizable compound, and subjected to dispersion treatment to prepare a dispersion of light-scattering particles. good.
Mixing and dispersing treatments can be performed using, for example, dispersing devices such as bead mills, paint conditioners, planetary stirrers, jet mills, and the like. It is preferable to use a bead mill or a paint conditioner from the viewpoint of improving the dispersibility of the light-scattering particles and facilitating adjustment of the average particle size of the light-scattering particles to a desired range.
Further, by mixing the light-scattering particles and the polymer dispersant before mixing the light-emitting nanocrystalline particles and the light-scattering particles, the light-scattering particles can be dispersed more sufficiently. Therefore, excellent ejection stability and excellent external quantum efficiency can be obtained more easily.

The method for producing an ink composition may further include, before the second step, a step of preparing a dispersion of luminescent nanocrystalline particles containing luminescent nanocrystalline particles and a photopolymerizable compound. In this case, in the second step, a dispersion of light-scattering particles and a dispersion of luminescent nanocrystalline particles are mixed.
In the step of preparing a dispersion of luminescent nanocrystalline particles, the dispersion of luminescent nanocrystalline particles may be prepared by mixing luminescent nanocrystalline particles and a photopolymerizable compound and performing dispersion treatment.
As the luminescent nanocrystalline particles, luminescent nanocrystalline particles having organic ligands on their surfaces may be used, or ligands may be used. That is, the dispersion of luminescent nanocrystalline particles may further contain an organic ligand or may contain a ligand.

Mixing and dispersing treatments can be performed using, for example, dispersing devices such as bead mills, paint conditioners, planetary stirrers, jet mills, and the like. It is preferable to use a bead mill, a paint conditioner, or a jet mill from the viewpoint of improving the dispersibility of the luminescent nanocrystalline particles and facilitating adjustment of the average particle size of the luminescent nanocrystalline particles to a desired range.
According to such a method, the luminescent nanocrystalline particles can be sufficiently dispersed. Therefore, it is possible to improve the optical properties (for example, external quantum efficiency) of the pixel portion, and to easily obtain an ink composition having excellent ejection stability.

In the above production method, the hindered amine compound may be mixed in the first step or the second step. That is, the first step may be a step of preparing a dispersion of light-scattering particles containing light-scattering particles and a hindered amine compound, and optionally a polymer dispersant and a photopolymerizable compound. The second step may be a step of mixing the dispersion of light-scattering particles, the luminescent nanocrystalline particles, the hindered amine-based compound, and, if necessary, the photopolymerizable compound.
The hindered amine compound may be mixed with the dispersion of luminescent nanocrystalline particles prepared before the second step.

In the above production method, when other components such as antioxidants and organic solvents are used, these components may be mixed with the dispersion of the luminescent nanocrystalline particles or the dispersion of the light-scattering particles. Alternatively, it may be mixed in a mixed dispersion obtained by mixing a dispersion of luminescent nanocrystalline particles and a dispersion of light-scattering particles.

<Ink composition set>
An ink composition set of one embodiment includes the ink composition of the embodiment described above. The ink composition set may include an ink composition that does not contain luminescent nanocrystalline particles (non-luminescent ink composition) in addition to the ink composition (luminescent ink composition) of the embodiment described above. A non-luminescent ink composition is, for example, a curable ink composition. The non-luminescent ink composition may be a conventionally known ink composition, and has the same composition as the ink composition (luminescent ink composition) of the above-described embodiment except that it does not contain luminescent nanocrystalline particles. may be

Since the non-luminous ink composition does not contain luminous nanocrystal particles, light is allowed to enter the pixel portion formed by the non-luminous ink composition (the pixel portion containing the cured product of the non-luminous ink composition). In this case, the light emitted from the pixel portion has substantially the same wavelength as the incident light. Therefore, the non-luminous ink composition is preferably used to form a pixel portion having the same color as the light from the light source. For example, when the light from the light source is light having a wavelength in the range of 420 to 480 nm (blue light), the pixel portion formed with the non-luminescent ink composition can be a blue pixel portion.

The non-luminescent ink composition preferably contains light-scattering particles. When the non-luminous ink composition contains light-scattering particles, the pixel portion formed from the non-luminous ink composition can scatter light incident on the pixel portion, thereby It is possible to reduce the light intensity difference in the viewing angle of the light emitted from the portion.

<Light conversion layer and color filter>
Hereinafter, details of the light conversion layer and the color filter obtained using the ink composition set of the embodiment described above will be described with reference to the drawings. In the following description, the same reference numerals are used for the same or corresponding elements, and overlapping descriptions are omitted.

FIG. 1 is a schematic cross-sectional view of a color filter according to one embodiment. As shown in FIG. 1 , the color filter 100 includes a base material 40 and a light conversion layer 30 provided on the base material 40 . The light conversion layer 30 includes a plurality of pixel portions 10 and a light shielding portion 20 .

The light conversion layer 30 has, as pixel sections 10, a first pixel section 10a, a second pixel section 10b, and a third pixel section 10c. The first pixel section 10a, the second pixel section 10b, and the third pixel section 10c are arranged in a grid so as to repeat this order. The light shielding portion 20 is provided between adjacent pixel portions, that is, between the first pixel portion 10a and the second pixel portion 10b, between the second pixel portion 10b and the third pixel portion 10c, and between the third pixel portion 10c. is provided between the first pixel portion 10c and the first pixel portion 10a. In other words, these adjacent pixel portions are separated by the light shielding portion 20 .

The first pixel portion 10a and the second pixel portion 10b are luminescent pixel portions (luminescent pixel portions) each containing a cured product of the ink composition of the embodiment described above. The cured product shown in FIG. 1 contains luminescent nanocrystalline particles, a curing component, and light scattering particles. The first pixel portion 10a includes a first curing component 13a, and first luminescent nanocrystalline particles 11a and first light scattering particles 12a respectively dispersed in the first curing component 13a. Similarly, the second pixel portion 10b includes a second curing component 13b, and second luminescent nanocrystalline particles 11b and second light scattering particles 12b dispersed in the second curing component 13b, respectively. including. The cured component is a component obtained by polymerization of a photopolymerizable compound, and contains a polymer of the photopolymerizable compound and metal atoms derived from a metal compound having a dithiocarbamic acid group. A metal compound having a dithiocarbamic acid group may exist in a state in which the metal atom and the ligand are bonded, or may exist in a state in which the metal atom and the ligand are separated. The metal atoms and ligands may each be adsorbed or coordinated (eg, bound) to the surface of the luminescent nanocrystalline particles. The curing component may include organic components (organic ligands, polymer dispersants, unreacted polymerizable compounds, etc.) contained in the ink composition, in addition to the above polymers. In the first pixel portion 10a and the second pixel portion 10b, the first curing component 13a and the second curing component 13b may be the same or different, and may be the first light scattering particles 12a. It may be the same as or different from the second light scattering particles 12b.

The first luminescent nanocrystalline particles 11a are red luminescent nanocrystalline particles that absorb light with a wavelength in the range of 420-480 nm and emit light with an emission peak wavelength in the range of 605-665 nm. That is, the first pixel section 10a can be rephrased as a red pixel section for converting blue light into red light. The second luminescent nanocrystalline particles 11b are green luminescent nanocrystalline particles that absorb light with a wavelength in the range of 420 to 480 nm and emit light with an emission peak wavelength in the range of 500 to 560 nm. That is, the second pixel section 10b can be rephrased as a green pixel section for converting blue light into green light.

The content of the luminescent nanocrystalline particles in the luminescent pixel portion is based on the total mass of the cured luminescent ink composition, from the viewpoint of obtaining an excellent effect of improving the external quantum efficiency and obtaining excellent emission intensity. It is preferably 5% by mass or more, and may be 10% by mass or more, 15% by mass or more, 20% by mass or more, or 30% by mass or more. The content of the luminescent nanocrystalline particles is preferably 80% by mass or less based on the total mass of the cured luminescent ink composition, from the viewpoint of obtaining excellent reliability of the pixel portion and excellent emission intensity. and may be 75% by mass or less, 70% by mass or less, or 60% by mass or less.

The content of the light-scattering particles in the luminescent pixel portion is 0.1% by mass or more and 1% by mass, based on the total mass of the cured luminescent ink composition, from the viewpoint of improving the external quantum efficiency. or more, or 3% by mass or more. The content of the light-scattering particles is 60% by mass or less, 50% by mass or less, based on the total mass of the cured luminescent ink composition, from the viewpoint of improving the external quantum efficiency and the reliability of the pixel portion. % by mass or less, 40% by mass or less, 30% by mass or less, 25% by mass or less, 20% by mass or less, or 15% by mass or less.

The third pixel portion 10c is a non-luminous pixel portion (non-luminous pixel portion) containing the cured non-luminous ink composition described above. The cured product does not contain luminescent nanocrystalline particles, but contains light-scattering particles and a curing component. That is, the third pixel portion 10c includes a third curing component 13c and third light scattering particles 12c dispersed in the third curing component 13c. The third curing component 13c is, for example, a component obtained by polymerizing a polymerizable compound, and includes a polymer of the polymerizable compound. The third light scattering particles 12c may be the same as or different from the first light scattering particles 12a and the second light scattering particles 12b.

For example, the third pixel section 10c has a transmittance of 30% or more for light with a wavelength in the range of 420 to 480 nm. Therefore, the third pixel section 10c functions as a blue pixel section when using a light source that emits light with a wavelength in the range of 420 to 480 nm. Note that the transmittance of the third pixel section 10c can be measured with a microspectroscope.

The content of the light-scattering particles in the non-luminous pixel portion is 1% by mass based on the total mass of the cured non-luminous ink composition, from the viewpoint of further reducing the difference in light intensity at viewing angles. or more, may be 5% by mass or more, or may be 10% by mass or more. From the viewpoint of further reducing light reflection, the content of the light-scattering particles may be 80% by mass or less, and 75% by mass or less, based on the total mass of the cured product of the non-luminous ink composition. It may be 70% by mass or less.

The thickness of the pixel portion (the first pixel portion 10a, the second pixel portion 10b, and the third pixel portion 10c) may be, for example, 1 μm or more, 2 μm or more, or 3 μm or more. may The thickness of the pixel portion (the first pixel portion 10a, the second pixel portion 10b, and the third pixel portion 10c) may be, for example, 30 μm or less, 20 μm or less, or 15 μm or less. may

The light shielding section 20 is a so-called black matrix that is provided for the purpose of separating adjacent pixel sections to prevent color mixture and for the purpose of preventing leakage of light from the light source. The material constituting the light shielding part 20 is not particularly limited, and in addition to metals such as chromium, curing of a resin composition in which light shielding particles such as carbon fine particles, metal oxides, inorganic pigments, organic pigments, etc. are contained in a binder polymer. objects, etc. can be used. As the binder polymer used here, one or a mixture of two or more resins such as polyimide resin, acrylic resin, epoxy resin, polyacrylamide, polyvinyl alcohol, gelatin, casein, cellulose, etc., photosensitive resin, O/W An emulsion-type resin composition (for example, an emulsified reactive silicone) can be used. The thickness of the light shielding portion 20 may be, for example, 0.5 μm or more and 10 μm or less.

The base material 40 is a transparent base material having optical transparency. A flexible base material or the like can be used. Among these, it is preferable to use a glass substrate made of alkali-free glass that does not contain an alkali component. Specifically, "7059 glass", "1737 glass", "Eagle 200" and "Eagle XG" manufactured by Corning, "AN100" manufactured by Asahi Glass Co., Ltd., "OA-10G" manufactured by Nippon Electric Glass Co., Ltd. and " OA-11” is preferred. These materials have a small coefficient of thermal expansion and are excellent in dimensional stability and workability in high-temperature heat treatment.

The color filter 100 including the light conversion layer 30 described above is suitably used when using a light source that emits light with a wavelength in the range of 420 to 480 nm.

The color filter 100 can be manufactured, for example, by forming the light-shielding portions 20 in a pattern on the substrate 40 and then forming the pixel portions 10 in the pixel-forming regions partitioned by the light-shielding portions 20 on the substrate 40. . The pixel portion 10 includes a step of selectively applying an ink composition (inkjet ink) to a pixel portion forming region on the base material 40 by an inkjet method, a step of drying the ink composition to remove the organic solvent, and a step of drying the ink composition. and a step of irradiating the ink composition of (1) with an active energy ray (eg, ultraviolet rays) to cure the ink composition to obtain a luminescent pixel portion. A luminescent pixel portion can be obtained by using the luminescent ink composition described above as the ink composition, and a non-luminescent pixel portion can be obtained by using a non-luminescent ink composition.

The method of forming the light shielding portion 20 is to form a thin film of a metal such as chromium or a thin film of a resin composition containing light shielding particles in a region that serves as a boundary between a plurality of pixel portions on one side of the substrate 40. and a method of patterning this thin film. The metal thin film can be formed, for example, by a sputtering method, a vacuum deposition method, or the like, and the thin film of the resin composition containing light-shielding particles can be formed, for example, by a method such as coating or printing. As a method for patterning, a photolithography method or the like can be used.

Examples of the ink jet method include the bubble jet (registered trademark) method using an electrothermal transducer as an energy generating element, and the piezo jet method using a piezoelectric element.

In drying the ink composition, at least part of the organic solvent should be removed, and it is preferable to remove all of the organic solvent. The method for drying the ink composition is preferably drying under reduced pressure (reduced pressure drying). From the viewpoint of controlling the composition of the ink composition, the drying under reduced pressure is usually carried out under a pressure of 1.0 to 500 Pa at 20 to 30° C. for 3 to 30 minutes.

For curing the ink composition, for example, a mercury lamp, a metal halide lamp, a xenon lamp, an LED, or the like may be used. The wavelength of the irradiated light may be, for example, 200 nm or more and 440 nm or less. The exposure dose may be, for example, 10 mJ/cm ² or more and 4000 mJ/cm ² or less.

Although one embodiment of the color filter, the light conversion layer, and the manufacturing method thereof has been described above, the present invention is not limited to the above embodiment.

For example, the light conversion layer may be a pixel portion ( blue pixel portion). In addition, the light conversion layer may include pixel portions (e.g., yellow pixel portions) containing a cured product of a luminescent ink composition containing nanocrystalline particles that emit light of a color other than red, green, and blue. good. In these cases, each of the luminescent nanocrystalline particles contained in each pixel portion of the light conversion layer preferably has a maximum absorption wavelength in the same wavelength range.

In addition, at least part of the pixel portion of the light conversion layer may contain a cured product of a composition containing a pigment other than the luminescent nanocrystalline particles.

In addition, the color filter may have an ink-repellent layer made of an ink-repellent material having a narrower width than the light-shielding portion on the pattern of the light-shielding portion. Further, instead of providing an ink-repellent layer, a photocatalyst-containing layer as a variable wettability layer is formed in a solid manner in a region including a pixel portion forming region, and then light is applied to the photocatalyst-containing layer through a photomask. By irradiating and exposing, the ink affinity of the pixel portion forming region may be selectively increased. Examples of photocatalysts include titanium oxide and zinc oxide.

In addition, the color filter may have an ink-receiving layer containing hydroxypropylcellulose, polyvinyl alcohol, gelatin, etc. between the base material and the pixel portion.

Also, the color filter may have a protective layer on the pixel portion. This protective layer flattens the color filter and prevents components contained in the pixel portion, or components contained in the pixel portion and components contained in the photocatalyst-containing layer from eluting into the liquid crystal layer. It is provided. Materials used for known color filter protective layers can be used for the protective layer.

Also, in manufacturing the color filter and the light conversion layer, the pixel portion may be formed by the photolithography method instead of the inkjet method. In this case, first, the ink composition is applied to the base material in layers to form an ink composition layer. Next, after the ink composition layer is exposed in a pattern, it is developed using a developer. Thus, a pixel portion made of a cured product of the ink composition is formed. Since the developer is usually alkaline, an alkali-soluble material is used as the material for the ink composition. However, the ink jet method is superior to the photolithography method from the viewpoint of efficiency in using materials. This is because the photolithographic method, in principle, removes approximately two-thirds or more of the material, thus wasting the material. Therefore, in the present embodiment, it is preferable to use inkjet ink and form the pixel portion by an inkjet method.

In addition to the luminescent nanocrystalline particles described above, the pixel portion of the light conversion layer of the present embodiment may further contain a pigment having substantially the same color as the luminescent color of the luminescent nanocrystalline particles. In order to contain the pigment in the pixel portion, the ink composition may contain the pigment.

Further, one or two of the red pixel portion (R), the green pixel portion (G), and the blue pixel portion (B) in the light conversion layer of the present embodiment are The pixel portion may contain a coloring material without containing crystal grains. As the coloring material that can be used here, known coloring materials can be used. For example, the coloring material used in the red pixel portion (R) includes a diketopyrrolopyrrole pigment and/or an anionic red organic dye. mentioned. The coloring material used in the green pixel portion (G) includes at least one selected from the group consisting of halogenated copper phthalocyanine pigments, phthalocyanine green dyes, and mixtures of phthalocyanine blue dyes and azo yellow organic dyes. Coloring materials used in the blue pixel portion (B) include ε-type copper phthalocyanine pigments and/or cationic blue organic dyes. When these colorants are contained in the light conversion layer, the amount used is 1 to 5 masses based on the total mass of the pixel portion (cured product of the ink composition) from the viewpoint of preventing a decrease in transmittance. %.

The ink composition of the invention is also suitable for light conversion films. Examples of methods for carrying the ink composition of the present invention on a substrate include spin coating, die coating, extrusion coating, roll coating, wire bar coating, gravure coating, spray coating, and dipping. Further, an organic solvent may be added to the ink composition during coating. Examples of organic solvents include hydrocarbon solvents, halogenated hydrocarbon solvents, ether solvents, alcohol solvents, ketone solvents, ester solvents, and aprotic solvents. , hydrocarbon solvents, halogenated hydrocarbon solvents, and ester solvents are preferred. Specific examples of organic solvents include toluene, hexane, heptane, cyclohexane, and methylcyclohexane. These may be used alone or in combination, and may be appropriately selected in consideration of the vapor pressure and the solubility of the luminescent particle-containing composition. As a method for volatilizing the added organic solvent, natural drying, drying by heating, drying under reduced pressure, and drying by heating under reduced pressure can be used. The thickness of the film may be appropriately adjusted depending on the application, but is preferably, for example, 0.1 μm or more and 10 mm or less, and particularly preferably 1 μm or more and 1 mm or less.

As for the shape of the substrate when the ink composition of the present invention is carried on the substrate, it may have a curved surface as a constituent part, in addition to the flat plate. The material constituting the substrate can be used regardless of whether it is an organic material or an inorganic material. Examples of organic materials for the substrate include polyethylene terephthalate, polycarbonate, polyimide, polyamide, polymethyl methacrylate, polystyrene, polyvinyl chloride, polytetrafluoroethylene, polychlorotrifluoroethylene, polyarylate, polysulfone, and triacetyl. Cellulose, cellulose, polyether ether ketone, etc., and inorganic materials include, for example, silicon, glass, calcite, and the like.

When the ink composition of the present invention is carried on a substrate and polymerized, it is desirable that the polymerization progresses rapidly. The temperature during irradiation is preferably within a temperature range in which the particle shape of the luminescent nanocrystalline particles is maintained. When a film is to be produced by photopolymerization, it is preferable to polymerize at a temperature as close to room temperature as possible, typically at 25° C., in order to avoid unintended induction of thermal polymerization. The intensity of the active energy ray is preferably 0.1 mW/cm ² or more and 2.0 W/cm ² or less. If the intensity is less ^than 0.1 mW/cm ² , it takes a long time to complete the photopolymerization, resulting in poor productivity. Alternatively, there is a risk that the ink composition will deteriorate.

The light conversion film that uses the ink composition of the present invention obtained by polymerization as a forming material can be subjected to heat treatment for the purpose of reducing initial changes in properties and stably developing properties. The heat treatment temperature is preferably in the range of 50 to 250° C., and the heat treatment time is preferably in the range of 30 seconds to 12 hours.

The light conversion film formed by the ink composition of the present invention produced by such a method may be used alone after peeling from the substrate, or may be used without peeling. Moreover, the obtained light conversion film may be laminated, or may be used by bonding to another substrate.

When the light conversion film using the ink composition of the present invention as a forming material is used in a laminated structure, the laminated structure may have arbitrary layers such as a substrate, a barrier layer, and a light scattering layer. Examples of the material constituting the substrate include those mentioned above. Examples of the structure of the laminated structure include a structure in which a light conversion film having the ink composition of the present invention as a forming material is sandwiched between two substrates. In that case, in order to protect the light conversion film formed from the ink composition from moisture and oxygen in the air, the peripheral portion between the substrates may be sealed with a sealing material. Examples of the barrier layer include polyethylene terephthalate and glass. A light scattering layer may be provided to uniformly scatter light. The light-scattering layer includes, for example, a layer containing the light-scattering particles and a light-scattering film. FIG. 2 is a cross-sectional view schematically showing the structure of the laminated structure of this embodiment. In FIG. 2, hatching indicating a cross section is omitted in order to avoid complication of the drawing. The laminated structure 50 has a light conversion film 54 of the present embodiment sandwiched between a first substrate 51 and a second substrate 52 . The light conversion film 54 is formed using an ink composition containing light scattering particles 541 and luminescent nanocrystalline particles 542 as a forming material. distributed over The light conversion film 54 is sealed with a sealing layer 53 made of a sealing material.

A laminated structure containing a light conversion film formed from the ink composition of the present invention is suitable for light emitting device applications. Examples of the configuration of the light-emitting device include a structure having a prism sheet, a light guide plate, a laminated structure containing the light-emitting particles of the present invention, and a light source. Light sources include, for example, light emitting diodes, lasers, and electroluminescent devices.

A laminated structure containing a light conversion film formed from the ink composition of the present invention is preferably used as a wavelength conversion member for displays. As an example of the structure when used as a wavelength conversion member, for example, a laminated structure in which a light conversion film containing the luminescent particle-containing composition of the present invention as a forming material is sealed between two barrier layers is attached to a light guide plate. A structure to be installed on top is mentioned. In this case, the blue light from the light emitting diodes installed on the side surface of the light guide plate is converted into green light or red light by passing through the laminated structure, and the blue light, green light, and red light are mixed. Since white light can be obtained, it can be used as a backlight for displays.

The present invention will be specifically described below with reference to examples. However, the present invention is not limited only to the following examples. All the materials used in the examples were obtained by introducing argon gas to replace dissolved oxygen with argon gas. Titanium oxide was used after being heated at 175° C. for 4 hours under a reduced pressure of 1 mmHg and left to cool in an argon gas atmosphere before mixing. The liquid materials used in the examples were dehydrated with molecular sieves 3A for 48 hours or more before mixing.

<Preparation of photopolymerizable compound>
[(Meth)acrylate compound having an acrylic equivalent of 110 or more]
・HDDA: 1,6-hexanediol diacrylate (acrylic equivalent: 113)
・DPGDA: dipropylene glycol diacrylate (acrylic equivalent: 121)
- DCPEA: dicyclopentenyloxyethyl acrylate (acrylic equivalent: 242)
- DCPEM: dicyclopentenyloxyethyl methacrylate (acrylic equivalent: 262)
・IB-XA: isobornyl acrylate (acrylic equivalent: 208)
· DCPA: dimethylol-tricyclodecane diacrylate (acrylic equivalent: 152)
・EOBPADA: EO-modified bisphenol A diacrylate (acrylic equivalent: 254)
[(Meth)acrylate compound having an acrylic equivalent of less than 110]
・ BDDA: 1,4-butanediol diacrylate (acrylic equivalent: 99)
・TMPTA: trimethylolpropane triacrylate (acrylic equivalent: 99)
[Allyl ether compound]
・AOMA: 2-(allyloxymethyl) methyl acrylate

<Preparation of a metal compound having a dithiocarbamic acid group>
・Compound 1: zinc dibutyldithiocarbamate (product name: Noxcellar BZ-P)
・Compound 2: Zinc N-pentamethylenedithiocarbamate (product name: Noxcellar ZP)
・Compound 3: sodium dibutyldithiocarbamate (product name: Noxcella TP)
・Compound 4: copper dimethyldithiocarbamate (product name: NOXCELLER TTCU)

<Preparation of antioxidant>
・Phenolic antioxidant: Irganox 1010 (Adeka Co., Ltd.)
・ Phosphorus antioxidant: PEP-8 (BASF Japan Co., Ltd. Adeka)

<Synthesis Example 1: Preparation of green-emitting InP/ZnSeS/ZnS nanocrystalline particles>
[Preparation of indium laurate solution]
10 g of 1-octadecene (ODE), 146 mg (0.5 mmol) of indium acetate and 300 mg (1.5 mmol) of lauric acid were added to the reaction flask to obtain a mixture. A clear solution (indium laurate solution) was obtained by heating the mixture at 140° C. for 2 hours under vacuum. This solution was kept in the glove box at room temperature until needed. In addition, since indium laurate has low solubility at room temperature and tends to precipitate, when using an indium laurate solution, the precipitated indium laurate in the solution (ODE mixture) should be heated to about 90° C. to obtain a transparent solution. After forming the solution, the desired amount was weighed out.

[Preparation of core (InP core) of green-emitting nanocrystalline particles]
5 g of trioctylphosphine oxide (TOPO), 1.46 g (5 mmol) of indium acetate and 3.16 g (15.8 mmol) of lauric acid were added to the reaction flask to obtain a mixture. The mixture was heated at 160° C. for 40 minutes under a nitrogen (N ₂ ) environment and then at 250° C. for 20 minutes under vacuum. The reaction temperature (temperature of the mixture) was then raised to 300° C. under a nitrogen (N ₂ ) environment. At this temperature, a mixture of 3 g of 1-octadecene (ODE) and 0.25 g (1 mmol) of tris(trimethylsilyl)phosphine was rapidly introduced into the reaction flask and the reaction temperature was maintained at 260°C. After 5 minutes, the reaction was stopped by removing the heater and the resulting reaction solution was cooled to room temperature. 8 ml of toluene and 20 ml of ethanol were then added to the reaction solution in the glove box. Subsequently, centrifugation was performed to precipitate the InP nanocrystalline particles, and the supernatant was decanted to obtain InP nanocrystalline particles. The resulting InP nanocrystal particles were then dispersed in hexane. As a result, a dispersion (hexane dispersion) containing 5% by mass of InP nanocrystal particles was obtained.

The hexane dispersion of InP nanocrystal particles obtained above and the indium laurate solution were charged into a reaction flask to obtain a mixture. The amounts of the hexane dispersion of InP nanocrystal particles and the indium laurate solution were adjusted to 0.5 g (25 mg of InP nanocrystal particles) and 5 g (178 mg of indium laurate), respectively. After allowing the mixture to stand at room temperature under vacuum for 10 minutes, the inside of the flask was returned to normal pressure with nitrogen gas, the temperature of the mixture was raised to 230°C, and the temperature was maintained for 2 hours to remove hexane from the inside of the flask. . Next, the temperature inside the flask was raised to 250°C, and a mixture of 3 g of 1-octadecene (ODE) and 0.03 g (0.125 mmol) of tris(trimethylsilyl)phosphine was rapidly introduced into the reaction flask, and the reaction temperature was raised to 230°C. maintained at After 5 minutes, the reaction was stopped by removing the heater and the resulting reaction solution was cooled to room temperature. Then, 8 ml of toluene and 20 ml of ethanol were added to the reaction solution in the glove box. Subsequently, centrifugation is performed to precipitate the InP nanocrystalline particles (InP cores), which are the cores of the green-emitting InP/ZnSeS/ZnS nanocrystalline particles. got Next, the obtained InP nanocrystalline particles (InP cores) were dispersed in hexane to obtain a dispersion (hexane dispersion) containing 5% by mass of InP nanocrystalline particles (InP cores).

[Formation of green-emitting nanocrystalline particle shell (ZnSeS/ZnS shell)]
After adding 2.5 g of the hexane dispersion of the InP nanocrystalline particles (InP cores) obtained above to the reaction flask, 0.7 g of oleic acid was added to the reaction flask at room temperature, and the temperature was raised to 80°C. and held for 2 hours. Then, 14 mg of diethylzinc dissolved in 1 ml of ODE, 8 mg of bis(trimethylsilyl)selenide and 7 mg of hexamethyldisilathiane (ZnSeS precursor solution) are added dropwise to this reaction mixture, and the temperature is raised to 200° C. and maintained for 10 minutes. This formed a ZnSeS shell with a thickness of 0.5 monolayer.

The temperature was then raised to 140°C and held for 30 minutes. Next, a ZnS precursor solution obtained by dissolving 69 mg of diethyl zinc and 66 mg of hexamethyldisilathiane in 2 ml of ODE was added dropwise to this reaction mixture, and the temperature was raised to 200° C. and maintained for 30 minutes to obtain A ZnS shell with a thickness of 2 monolayers was formed. Ten minutes after the addition of the ZnS precursor solution, the reaction was stopped by removing the heater. The reaction mixture was then cooled to room temperature and the resulting white precipitate was removed by centrifugation to yield a transparent nanocrystalline particle dispersion (InP/ZnSeS) with green-emitting InP/ZnSeS/ZnS nanocrystalline particles dispersed therein. /ODE dispersion of ZnS nanocrystalline particles) was obtained.

[Synthesis of organic ligands for InP/ZnSeS/ZnS nanocrystalline particles]
(Synthesis of organic ligand)
After introducing polyethylene glycol |average Mn400| (manufactured by Sigma-Aldrich) into the flask, while stirring in a nitrogen gas environment, polyethylene glycol |average Mn400| made) was added. The internal temperature of the flask was raised to 80° C. and stirred for 8 hours to obtain an organic ligand represented by the following formula (A) as a pale yellow viscous oil.

[Preparation of Green-Emitting InP/ZnSeS/ZnS Nanocrystalline Particle Dispersion by Ligand Exchange]
30 mg of the above organic ligand was added to 1 ml of the ODE dispersion of InP/ZnSeS/ZnS nanocrystalline particles obtained above. Ligand exchange was then performed by heating at 90° C. for 5 hours. Aggregation of nanocrystalline particles was observed as the ligand exchange progressed. After completion of ligand exchange, the supernatant was decanted to obtain nanocrystalline particles. Then, 3 ml of ethanol was added to the resulting nanocrystalline particles, and ultrasonically treated to redisperse them. 10 ml of n-hexane was added to 3 ml of the obtained ethanol dispersion of nanocrystalline particles. Subsequently, after centrifugation was performed to precipitate the nanocrystalline particles, the supernatant was decanted and dried under vacuum to obtain luminescent particles 1 (InP/ZnSeS/ZnS nanocrystalline particles modified with the above organic ligands). The content of organic ligands in the total amount of nanocrystalline particles modified with organic ligands was 35% by mass.

<Synthesis Example 2. Preparation of Green Light-Emitting Particle 2 (Silica-Coated CsPbBr ₃ )>
First, 6.0 g of cesium carbonate, 250 mL of 1-octadecene, and 25 mL of oleic acid were mixed to obtain a mixture. Next, this mixed solution was dried under reduced pressure at 120° C. for 30 minutes, and then heated at 150° C. under an argon atmosphere. This gave a cesium-oleic acid solution.

On the other hand, 5.0 g of lead (II) bromide, 375 mL of 1-octadecene, and 37.5 mL of oleic acid were mixed to obtain a mixed solution. Next, this mixed solution was dried under reduced pressure at 90° C. for 10 minutes, and then 37.5 mL of 3-aminopropyltriethoxysilane (APTES) was added to the mixed solution under an argon atmosphere. After drying under reduced pressure for another 20 minutes, it was heated at 140° C. under an argon atmosphere.

After that, 37.5 mL of the cesium-oleic acid solution was added to the mixed solution containing lead (II) bromide at 150°C, and the mixture was reacted by heating and stirring for 5 seconds, and then cooled in an ice bath. 3 L of methyl acetate was then added. After centrifuging the resulting suspension (10,000 rpm, 1 minute), the supernatant was removed, mixed with toluene, and stirred for 2 hours. Thereafter, silica-coated green light-emitting particles 2 were obtained by removing toluene. The nanocrystals constituting the luminescent particles 2 were perovskite-type lead tribromide cesium crystals, and their average particle diameter was 10 nm when analyzed by scanning transmission electron microscopy.

<Synthesis Example 3. Preparation of green light-emitting particles 3 (silica-coated FAPbBr ₃ )>
In an argon atmosphere, 0.4 g of formamidine acetate and 12.5 ml of oleic acid were added to a three-necked flask. After degassing under reduced pressure with stirring at room temperature for 18 hours while reducing the pressure with a vacuum pump, the mixture was heated and stirred at 120° C. for 30 minutes. The vacuum was released in the argon atmosphere to obtain a formamidine-oleic acid solution.

Meanwhile, 1.0 g of lead bromide (II), 7.5 mL of oleic acid, and 75 mL of 1-octadecene were added to a three-necked flask under an argon atmosphere. The mixture was heated and stirred at 90° C. for 10 minutes while reducing the pressure with a vacuum pump. The vacuum was released while the argon atmosphere was maintained, and 7.5 mL of 3-aminopropyltriethoxysilane (APTES) was added. The mixture was stirred at 90° C. until a uniform solution was obtained.

After that, 11.6 mL of the formamidine-oleic acid solution was added to the mixed solution containing lead (II) bromide at 140° C., and the mixture was reacted by heating and stirring for 5 seconds, and then cooled in an ice bath. 3 L of methyl acetate was then added. After centrifuging the resulting suspension (10,000 rpm, 1 minute), the supernatant was removed, mixed with toluene, and stirred for 2 hours. Thereafter, silica-coated green light-emitting particles 3 were obtained by removing toluene. The nanocrystals constituting the luminescent particles 3 were perovskite-type formamidium lead bromide crystals, and the average particle diameter thereof was 10 nm when analyzed by scanning transmission electron microscope observation.
<Synthesis Example 4. Preparation of Green Light Emitting Particle 4 (Silica Multi-layer Coating FAPbBr ₃ )>
4 g of a block copolymer (S2VP, manufactured by PolymerSource.) having a structure represented by the following formula (B4) was added to 400 mL of toluene and dissolved by heating at 60°C. Luminescent particles 3 were added to a toluene solution in which the block copolymer was dissolved so that the concentration of the luminescent particles 3 was 0.16% by mass, stirred for 15 minutes, centrifuged, and the supernatant was collected. , luminescent particles 3 and a block copolymer were obtained.

To 100 mL of the toluene dispersion, 5 mL of a compound represented by the following formula (C4) (MS-51, manufactured by Colcoat Co., Ltd., the average value of m in formula (C4) is 4) was added and stirred for 5 minutes. Then, 0.25 mL of ion-exchanged water was further added and stirred for 2 hours.

After centrifuging the resulting solution at 9,000 rpm for 5 minutes, 100 mL of the supernatant was recovered to obtain a toluene dispersion of luminescent particles 4 in which the luminescent particles 3 were further coated with silica. rice field. Luminescent particles 4 were obtained by removing toluene from this dispersion. The average particle size of the luminescent particles 4 was measured using a dynamic light scattering nanotrack particle size distribution meter and found to be 95 nm. In addition, when the element distribution of the luminescent particles 4 was evaluated by an energy dispersive X-ray analysis method (STEM-EDS) using a scanning transmission electron microscope, it was confirmed that the surface layer of the luminescent particles contained Si. . When the thickness of the surface layer was measured, it was about 5 nm. Further, for the luminescent particles, weight reduction was confirmed in the range of 200 to 550 ° C. by thermogravimetric differential thermal analysis (TG-DTA; temperature increase rate 10 ° C./min, under nitrogen atmosphere) measurement. was suggested to contain On the other hand, the used block copolymer was identified as a component by pyrolysis gas chromatograph mass spectrometer (TD/Py-GC/MS) measurement.

<Production Example 1: Preparation of Light-scattering Particle Dispersion 1>
In a container filled with argon gas, 50.0 g of titanium oxide (trade name: CR-60-2, manufactured by Ishihara Sangyo Co., Ltd., average particle diameter (volume average diameter): 210 nm) and a polymer dispersant (product Name: Ajisper PB-821, manufactured by Ajinomoto Fine-Techno Co., Ltd.) was mixed with 45.0 g of HDDA, then zirconia beads (diameter: 1.25 mm) were added to the resulting mixture and a paint conditioner was used. The mixture was subjected to dispersion treatment by shaking for 2 hours, and the zirconia beads were removed with a polyester mesh filter to obtain a light-scattering particle dispersion 1 (titanium oxide content: 50% by mass).

<Production Example 2: Preparation of Light-scattering Particle Dispersion 2>
In a container filled with argon gas, 50.0 g of titanium oxide (trade name: CR-60-2, manufactured by Ishihara Sangyo Co., Ltd., average particle diameter (volume average diameter): 210 nm) and a polymer dispersant (product Name: Ajisper PB-821, manufactured by Ajinomoto Fine-Techno Co., Ltd.) was mixed with 5.0 g of BDDA, and then zirconia beads (diameter: 1.25 mm) were added to the resulting mixture and a paint conditioner was used. The mixture was subjected to dispersion treatment by shaking for 2 hours, and the zirconia beads were removed with a polyester mesh filter to obtain a light-scattering particle dispersion 2 (titanium oxide content: 50% by mass).

<Preparation of green ink composition>
(Example 1)
(Adjustment of ink composition 1)
Luminous particle 1, HDDA, compound 1, photopolymerization initiator (phenyl (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (IGM Resin, trade name: Omnirad TPO)), light scattering Particle Dispersion Production Example 1 was blended so that the content of each component was as shown in Table 1 (unit: parts by mass), uniformly mixed in a container filled with argon gas, and then placed in a glove box. Inside, the mixture was filtered through a filter with a pore size of 5 μm, and argon gas was introduced into the container containing the obtained filtrate, and the inside of the container was saturated with argon gas. Ink composition 1 of Example 1 was obtained by removing.

(Preparation of light conversion layer 1)
The ink composition 1 was applied on a glass substrate in the air by a spin coater so as to have a film thickness of 10 μm. In a nitrogen atmosphere, the coating film was cured by irradiating UV light with a UV irradiation device using an LED lamp having a dominant wavelength of 395 nm so that the integrated light amount was 1500 mJ/cm ² , and a cured product of ink composition 1 was formed on a glass substrate. A layer (light conversion layer 1) consisting of was formed.

(Measurement of EQE)
A blue LED (peak emission wavelength: 450 nm) manufactured by CCS Co., Ltd. was used as a surface emitting light source. As a measurement device, an integrating sphere was connected to a radiation spectrophotometer (trade name “MCPD-9800”) manufactured by Otsuka Electronics Co., Ltd., and the integrating sphere was placed above the blue LED. The produced evaluation sample (light conversion layer 1) was inserted between the blue LED and the integrating sphere, and the spectrum observed by lighting the blue LED and the illuminance at each wavelength were measured.

The external quantum efficiency was obtained as follows from the spectrum and illuminance measured by the above measuring device. The external quantum efficiency is a value indicating how much of the light (photons) incident on the light conversion layer is emitted to the observer side as fluorescence. Therefore, if this value is large, it indicates that the light conversion layer is excellent in light emission characteristics, which is an important evaluation index.
EQE (%) = P1 (Green)/E (Blue) x 100

Here, E (Blue) and P1 (Green) respectively represent the following.
E (Blue): Represents the total value of “illuminance×wavelength/hc” in the wavelength range of 380 to 490 nm.
P1 (Green): Represents the total value of “illuminance×wavelength/hc” in the wavelength range of 500 to 650 nm.
These are values corresponding to the number of photons observed. In addition, h represents Planck's constant and c represents the speed of light.

(Heat resistance evaluation)
The prepared evaluation sample (light conversion layer 1) was transferred onto a 180° C. hot plate placed in a glove box under a nitrogen atmosphere and heated for 30 minutes. After cooling the evaluation sample to room temperature, EQE was measured in the same manner as the above EQE evaluation in the atmosphere, and the rate of change in EQE (1-[EQE after heating]/[EQE before heating] x 100). asked for The heat resistance of the evaluation samples was evaluated according to the following criteria.
[Evaluation criteria]
◎: 95% or more ○: 90% or more and less than 95% △: 80% or more and less than 90% ×: less than 80%

(Evaluation of stability against excitation light)
Trimethylolpropane EO-added trimethylolpropane EO-added trimethylolpropane-EO solution in which 1.0 part by mass of TPO was dissolved as a photopolymerization initiator was placed on the film of the sample (light conversion layer 1) prepared by heating at 180° C. for 30 minutes in the same manner as in the heat resistance evaluation. 30 μL of acrylate solution was added dropwise. Furthermore, a cover glass is attached from above, and a UV irradiation device using an LED lamp with a main wavelength of 395 nm is irradiated with UV so that the integrated light amount becomes 1500 mJ / cm ² . A sample was prepared. Subsequently, using an LED irradiation device with a dominant wavelength of 450 nm, the prepared sealed sample was irradiated with blue light at an intensity of 400 mW / cm ² for 150 hours, and EQE was measured in the same manner as the above EQE evaluation. A rate of change in EQE (1−[EQE after blue light irradiation]/[EQE before blue light irradiation]×100) was obtained. Stability evaluation of the evaluation sample against excitation light was performed according to the following criteria.
[Evaluation criteria]
◎: 85% or more ○: 75% or more and less than 85% △: 65% or more and less than 75% ×: less than 65%

(Examples 2 to 9 and Comparative Example 1)
(Adjustment of ink composition 2)
Ink composition 1 was prepared in the same manner as in Example 2, except that a photopolymerizable compound obtained by mixing 60 parts by mass, 30 parts by mass, and 10 parts by mass of HDDA, DCPEA, and AOMA, respectively, was used instead of HDDA. was obtained.

(Adjustment of ink composition 3)
Ink composition 1 was prepared in the same manner as in Example 3, except that a photopolymerizable compound obtained by mixing 60 parts by mass, 30 parts by mass, and 10 parts by mass of HDDA, DCPEMA, and AOMA, respectively, was used instead of HDDA. was obtained.

(Adjustment of ink composition 4)
Ink composition 1 was prepared in the same manner as in Example 4, except that a photopolymerizable compound obtained by mixing 60 parts by mass, 30 parts by mass, and 10 parts by mass of DPGDA, DCPEA, and AOMA, respectively, was used instead of HDDA. was obtained.

(Adjustment of ink composition 5)
Ink Composition 5 of Example 5 was obtained in the same manner as Ink Composition 2, except that Compound 2 was used instead of Compound 1 as the metal compound having a dithiocarbamic acid group.

(Adjustment of ink composition 6)
Ink Composition 6 of Example 6 was obtained in the same manner as Ink Composition 2, except that Compound 3 was used instead of Compound 1 as the metal compound having a dithiocarbamic acid group.

(Adjustment of ink composition 7)
Ink Composition 7 of Example 7 was obtained in the same manner as Ink Composition 2, except that Compound 4 was used instead of Compound 1 as the metal compound having a dithiocarbamic acid group.

(Adjustment of ink composition 8)
Ink Composition 8 of Example 8 was obtained in the same manner as Ink Composition 2, except that PEP-8 was added as a phosphorus antioxidant.

(Adjustment of ink composition 9)
Ink Composition 9 of Example 9 was obtained in the same manner as Ink Composition 8, except that Irganox 1010 was further added as a phenolic antioxidant.

(Adjustment of ink composition C1)
Preparation of Ink Composition 1, except that BDDA was used as the photopolymerizable compound instead of HDDA, and Light-scattering Particle Dispersion Production Example 2 was used instead of Light-scattering Particle Dispersion Production Example 1. Ink composition C1 of Comparative Example 1 was obtained in the same manner as above.

(Production of light conversion layers 2 to 9 and C1)
Light conversion layers 2 to 9 and C1 were produced under the same conditions as in the production of light conversion layer 1, except that the ink compositions were changed to compositions 2 to 9 and C1. The obtained light conversion layers 2 to 9 and C1 were evaluated for heat resistance and stability against excitation light.
Table 1 shows the results.

As shown in Examples 1 to 9, the light conversion layers using the ink compositions 1 to 9 of the present invention have higher heat resistance than the light conversion layer using the ink composition C1 of Comparative Example 1. It can be seen that the property evaluation and the stability to excitation light are good. This is because, in an ink composition containing both a photopolymerizable compound having an acrylic equivalent within a specific range and a dithiocarbamate group-containing metal compound, radicals of the dithiocarbamate group-containing metal compound are formed in the light conversion layer formed from the composition. It is considered that the trapping function works effectively, and as a result, deterioration is suppressed. Further, as shown in Examples 8 and 9, the light conversion layers using the ink compositions 8 and 9 of the present invention are formed from the ink composition further containing an antioxidant, and have excellent heat resistance and It can be seen that the stability against excitation light is good.

(Examples 10 to 12 and Comparative Example 2)
(Adjustment of ink composition 10)
Green light-emitting particles 2, compound 1, production example 1 of light-scattering particle dispersion, HDDA, IB-XA, and photopolymerization initiator (phenyl(2,4,6-trimethylbenzoyl-diphenyl-phosphine Oxide (manufactured by IGM resin, trade name: Omnirad TPO), Irganox 1010, and PEP-8 were blended so that the content of each component was shown in Table 2 (unit: parts by mass), and argon gas was added. After uniformly mixing in a container filled with argon, the mixture was filtered through a filter with a pore size of 5 μm in a glove box. Ink Composition 10 of Example 10 was obtained by saturating with gas and then removing the argon gas under reduced pressure.

(Adjustment of ink composition 11)
Ink Composition 11 of Example 11 was obtained in the same manner as Ink Composition 10 except that Green Light-Emitting Particles 3 were used instead of Green Light-Emitting Particles 2 .

(Adjustment of ink composition 12)
Ink Composition 12 of Example 12 was obtained in the same manner as Ink Composition 10 except that Green Light-Emitting Particles 4 were used instead of Green Light-Emitting Particles 2 .
(Adjustment of ink composition C2)
Preparation of Ink Composition 10, except that BDDA was used as the photopolymerizable compound instead of HDDA and IB-XA, and Light-scattering Particle Dispersion Production Example 2 was used instead of Light-scattering Particle Dispersion 1. Ink composition C2 of Comparative Example 2 was obtained in the same manner as above.
(Production of light conversion layers 10 to 12 and C2)
Light conversion layers 10 to 12 and C2 were produced under the same conditions as in the production of light conversion layer 1, except that the ink composition was changed to Compositions 10 to 12 and C2. The obtained light conversion layers 10 to 12 and C2 were evaluated for heat resistance and stability against excitation light.
Table 2 shows the results.

As shown in Examples 10 to 12, the light conversion layer using the ink compositions 10 to 12 of the present invention has a higher heat resistance than the light conversion layer using the ink composition C2 of Comparative Example 2. It can be seen that the property evaluation and the stability to excitation light are good. In particular, the light conversion layers of Examples 11 and 12 have better heat resistance and stability against excitation light than the light conversion layer of Comparative Example 2. It is speculated that in the presence of a photopolymerizable compound having an acrylic equivalent within the range, radical scavenging by the dithiocarbamic acid group-containing metal compound occurs effectively, thereby suppressing deterioration.

(Examples 13 to 16 and Comparative Example 3)
(Adjustment of ink composition 13)
Green light-emitting particles 2, compound 1, production example 1 of light-scattering particle dispersion, HDDA, IB-XA, DCPA, and a photopolymerization initiator (phenyl(2,4,6-trimethylbenzoyl-diphenyl -Phosphine oxide (manufactured by IGM resin, trade name: Omnirad TPO), Irganox 1010, and PEP-8 were blended so that the content of each component was the amount shown in Table 3 (unit: parts by mass). , After uniformly mixing in a container filled with argon gas, the mixture was filtered through a filter with a pore size of 5 μm in a glove box, and argon gas was introduced into the container containing the obtained filtrate. The inside of the flask was saturated with argon gas, and the pressure was reduced to remove the argon gas, thereby obtaining Ink Composition 13 of Example 13.

(Adjustment of ink composition 14)
Ink Composition 14 of Example 14 was obtained in the same manner as Ink Composition 13 except that Green Light-Emitting Particles 3 were used instead of Green Light-Emitting Particles 2 .

(Adjustment of ink composition 15)
Ink Composition 15 of Example 15 was obtained in the same manner as Ink Composition 13 except that Green Light-Emitting Particles 4 were used instead of Green Light-Emitting Particles 2 .

(Adjustment of ink composition 16)
Ink Composition 16 of Example 16 was obtained in the same manner as Ink Composition 13, except that EO-BPADA was used as the photopolymerizable compound instead of DCPA.

(Adjustment of ink composition C3)
Except that BDDA and TMPTA were used as photopolymerizable compounds instead of HDDA, IB-XA, and DCPA, and that Production Example 2 of Light-scattering Particle Dispersion was used instead of Production Example 1 of Light-scattering Particle Dispersion. Ink Composition C3 of Comparative Example 3 was obtained in the same manner as Ink Composition 13.

(Production of light conversion films 13 to 16 and C3)
Ink Compositions 13 to 16 and C3 were applied onto a glass substrate to a film thickness of 100 μm, and another glass substrate was attached. Under a nitrogen atmosphere, the coated glass was cured by irradiating UV with a UV irradiation device using an LED lamp with a dominant wavelength of 395 nm so that the integrated light amount was 1 J/cm ² to obtain light conversion films 13 to 16 and C3. . The obtained light conversion films 13 to 16 and C3 were evaluated for heat resistance and stability against excitation light.
Table 3 shows the results.

As shown in Examples 13 to 16, the light conversion films using the ink compositions 13 to 16 of the present invention had better heat resistance and It can be seen that the stability against excitation light is good. In particular, the light conversion film of Example 15 is extremely good as compared with the light conversion film of Comparative Example 3. Therefore, even in the durability imparting particles coated with silica, the photopolymerizable compound having an acrylic equivalent within a specific range In the presence of the dithiocarbamic acid group-containing metal compound, radical scavenging effectively occurs, presumably suppressing deterioration.

From the above results, it is clear that the light conversion layer and the light conversion film obtained by the ink composition of the present invention have high stability against heat and light.

DESCRIPTION OF SYMBOLS 10... Pixel part 10a... 1st pixel part 10b... 2nd pixel part 10c... 3rd pixel part 11a... 1st luminescent nanocrystal particle 11b... 2nd luminescent nanocrystal particle , 12a... First light-scattering particles, 12b... Second light-scattering particles, 12c... Third light-scattering particles, 20... Light shielding part, 30... Light conversion layer, 40... Base material, 100... Color Filter 50 Laminated structure 51 First substrate 52 Second substrate 53 Sealing layer 54 Light conversion film 541 Light scattering particles 542 Luminescent particles

Claims

containing luminescent nanocrystalline particles, a photopolymerizable compound, and a metal compound having a dithiocarbamic acid group;
An ink composition comprising a (meth)acrylate compound having an acrylic equivalent of 110 or more as the photopolymerizable compound.
The ink composition according to claim 1, wherein the metal compound is a metal compound selected from the group consisting of zinc compounds, sodium compounds, and copper compounds.
3. The ink composition according to claim 1, wherein the (meth)acrylate compound contains a compound represented by the following formula (I).

[In formula (I), R 1 represents a hydrogen atom or a methyl group, R 2 represents an optionally substituted linear or branched alkylene group having 1 to 20 carbon atoms, m is 1 Represents an integer from ~10. Two R 1s may be the same or different. ]
The ink composition according to claim 1 or 2, which contains a monofunctional (meth)acrylate compound as the photopolymerizable compound.
The ink composition according to claim 1 or 2, wherein the monofunctional (meth)acrylate compound is a monofunctional (meth)acrylate containing an alicyclic structure.
The ink composition according to claim 1 or 2, further containing a phenolic antioxidant.
The ink composition according to claim 1 or 2, further containing a phosphorus antioxidant.
The ink composition according to claim 1 or 2, which is used for forming a light conversion layer.
The ink composition according to claim 1 or 2, which is used in an inkjet method.
comprising a plurality of pixel portions and a light shielding portion provided between the plurality of pixel portions;
The light conversion layer, wherein the plurality of pixel portions have luminescent pixel portions containing a cured product of the ink composition according to claim 1 or 2.
As the luminescent pixel portion,
a first luminescent pixel portion containing luminescent nanocrystalline particles that absorb light with a wavelength in the range of 420 to 480 nm and emit light with an emission peak wavelength in the range of 605 to 665 nm;
a second luminescent pixel portion containing luminescent nanocrystalline particles that absorb light with a wavelength in the range of 420 to 480 nm and emit light with an emission peak wavelength in the range of 500 to 560 nm;
11. The light conversion layer of claim 10, comprising:
The light conversion layer according to claim 10, further comprising a non-luminous pixel portion containing light scattering particles.
A color filter comprising the light conversion layer according to claim 10.
A light conversion film comprising a cured product of the ink composition according to claim 1 or 2.