JP2019026778A - Ink composition and method for producing the same, photoconversion layer and color filter - Google Patents

Abstract

To provide an ink composition of which the stability in the atmosphere is improved and a method for producing the same, and a photoconversion layer and a color filter each using the ink compositions.SOLUTION: The ink composition is provided that contains: light-emitting nanocrystal particles; a curing component formed from a photopolymerizable compound and/or thermosetting resin; and a single oxygen quencher. There are also provided; a photoconversion layer formed from a cured product of the ink composition; and a color filter comprising a photoconversion layer comprising a plurality of pixel parts, where each of the plurality of pixel parts has a pixel part including the cured product of the ink composition.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an ink composition and a method for producing the same, a light conversion layer, and a color filter.

  Conventionally, a color filter pixel portion in a display such as a liquid crystal display device uses, for example, a curable resist material containing red organic pigment particles or green organic pigment particles and an alkali-soluble resin and / or an acrylic monomer. Have been manufactured by photolithography.

  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, luminescent nanocrystal particles such as quantum dots, quantum rods, and other inorganic phosphor particles A method of forming a color filter pixel portion such as a red pixel and a green pixel by using the above has been actively studied.

  By the way, in the manufacturing method of the color filter by the said photolithography method, there existed a fault that resist materials other than the pixel part containing the comparatively expensive luminescent nanocrystal particle | grains were wasted from the characteristic of the manufacturing method. Under such circumstances, in order to eliminate the waste of the resist material as described above, it has begun to consider forming the light conversion substrate pixel portion by the ink jet method.

  However, the quantum dot ink and its film-formed product have a problem of deteriorating in the presence of oxygen and water contained in the atmosphere. In addition, when quantum dot ink contains a photopolymerizable component and is cured with ultraviolet light, or after irradiation with ultraviolet light or visible light in the presence of oxygen or water in the air in the post-process after manufacturing the quantum dot-containing film, It was found that the dots are likely to deteriorate.

  Although it is theoretically thought that these problems can be improved if the quantum dots are completely isolated from oxygen and moisture, for example, when applying a large area of quantum dot ink or manufacturing a large area printed matter, It is practically difficult to completely isolate the coated material and the printed material from the atmosphere, and there is a big problem in industrial application.

  Specifically, it is required to fill a part or most of the coating apparatus and the printing apparatus with an inert gas, which entails a huge capital investment and a high running cost. Therefore, a method for improving these problems and an ink with improved methods are desired.

  As a countermeasure technique known so far, Patent Document 1 describes a light-emitting ink composition having a small amount of oxygen and moisture. In Patent Document 1, a light-emitting element using OLED as a light-emitting material is created by a process under an inert gas in the atmosphere or in a glove box, and the life of the light-emitting element is evaluated. It is disclosed that there is. However, there is no disclosure as to whether or not a specific technical effect is manifested with respect to quantum dots (QD) made of luminescent nanocrystal particles, and it is unclear how much technical effect there is about quantum dots. It was. Moreover, the light emitting material for OLED shown in the Examples does not have a wavelength conversion function and cannot be diverted to a light conversion layer using quantum dots.

  Patent Document 2 discloses the time dependency of the illuminance Lv of a light emitter using a quantum dot composition with reduced oxygen and moisture, but was unclear about heat resistance and deterioration due to light irradiation. . In addition, whether or not there is a relationship between the dissolved oxygen concentration and the effect of individual evaluation items has not been experimentally shown specifically, and remains unknown.

  In other words, the above-mentioned known documents are merely a result of the oxygen source, which is a generalization / superordinate concept of oxygen, that causes heat resistance and deterioration due to light irradiation.

Special table 2006-501430 gazette US2014 / 0027673 Specification

  Since an ink composition using luminescent nanocrystal particles and a light conversion layer using the ink composition are unstable in the atmosphere, stability needs to be improved. There is a need to improve instability, especially when exposed to light in the atmosphere.

  An ink composition having improved stability in the atmosphere, particularly excellent in stability when exposed to light in the atmosphere, a method for producing the same, and a light conversion layer and a color filter using the ink composition The purpose is to provide.

  The present invention provides the inventions of the following embodiments, respectively.

According to the following ink composition 1, since it contains a singlet oxygen quencher, the stability of the cured product in the air can be improved.
1. An ink composition comprising luminescent nanocrystal particles, a curing component, and a singlet oxygen quencher.
2. 2. The ink composition according to 1, wherein the singlet oxygen quencher is a compound having a quenching rate constant of singlet oxygen of k = 10 ⁷ M ⁻¹ s ⁻¹ or more.
3. The singlet oxygen quencher is a nickel compound, a diimonium salt, 1,4-diazabicyclo [2.2.2. The ink composition according to 1 or 2, wherein the ink composition is at least one compound selected from the group consisting of octane, aniline compound, luminol, bilirubin, β-carotene, and furan compound.
4). The ink composition according to any one of 1 to 3, wherein the curable component is a thermosetting resin.
5). The ink composition according to any one of 1 to 3, wherein the curing component is a photopolymerizable compound.
6). 6. The ink composition as described in 5 above, wherein the photopolymerizable compound is a radical photopolymerizable compound.
7). 6. The ink composition according to 5 above, wherein the photopolymerizable compound is insoluble in alkali.
8). 5. The ink composition as described in 4 above, wherein the thermosetting resin is alkali-insoluble.
9. 9. The ink composition as described in 7 or 8 above, which can form an alkali-insoluble coating film.
10. The ink composition according to any one of 1 to 3, wherein the dissolved oxygen concentration is 0 to 6 mg / L.
11. The ink composition according to any one of 1 to 3, wherein the ink composition is for inkjet printing.
12 12. The ink composition for inkjet according to 11, wherein the surface tension is 20 to 40 mN / m.
13. 12. The inkjet ink composition according to 11 above, wherein the viscosity is 2 to 20 mPa · s.
14 12. The inkjet ink composition according to 11 above, further comprising a solvent having a boiling point of 180 ° C. or higher.
15. 12. The inkjet ink composition as described in 11 above, which is used for a color filter.

16. The light conversion layer which consists of hardened | cured material of the ink composition as described in any one of said 1-3.
17. A light conversion layer, wherein the light conversion layer comprising a cured product of the ink composition described in the previous term 9 is alkali-insoluble.
18. A light conversion layer comprising a plurality of pixel portions,
The plurality of pixel portions are light conversion layers having pixel portions including a cured product of the inkjet ink composition according to any one of the above 11 to 15.
19. A light shielding part provided between the plurality of pixel parts;
The plurality of pixel portions are
The light-emitting nanocrystal particles containing the cured product and containing the light-emitting nanocrystal particles that absorb light having a wavelength in the range of 420 to 480 nm and emit light having an emission peak wavelength in the range of 605 to 665 nm are included. A first pixel portion;
The light-emitting nanocrystal particles containing the cured product and containing the light-emitting nanocrystal particles that absorb light having a wavelength in the range of 420 to 480 nm and emit light having a light emission peak wavelength in the range of 500 to 560 nm. The light conversion layer according to claim 11, further comprising: a second pixel portion.
20. 20. The light conversion layer according to 19, wherein the plurality of pixel portions further include a third pixel portion having a transmittance of 30% or more for light having a wavelength in a range of 420 to 480 nm.
21. A color filter comprising the light conversion layer according to any one of 17 to 20.

  An ink composition having improved stability in the atmosphere, particularly excellent in stability when exposed to light in the atmosphere, a method for producing the same, and a light conversion layer and a color filter using the ink composition Can be provided.

FIG. 1 is a schematic cross-sectional view of a color filter according to an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail.

<Ink composition>
The ink composition of the embodiment contains luminescent nanocrystal particles, a curing component, and a singlet oxygen quencher.

  The ink composition of one embodiment is a color filter ink composition used for forming a pixel portion of a color filter by a method such as a photolithography method or an ink jet method.

  The ink composition of one embodiment is suitably used for forming a color filter pixel portion by an ink jet method.

  Using a conventional ink composition, for example, when forming a color filter pixel portion by an inkjet method, when exposed to ultraviolet light in the atmosphere, or after being exposed to ultraviolet light or visible light after forming a light conversion layer, There was a problem that the light conversion layer deteriorated.

  On the other hand, according to the ink composition of the embodiment, such a problem can be improved.

  Hereinafter, the color filter ink composition (color filter inkjet ink) used in the inkjet method will be described as an example.

[Luminescent nanocrystal particles]
The luminescent nanocrystal particle is a nano-sized crystal that absorbs excitation light and emits fluorescence or phosphorescence. For example, the maximum particle diameter measured by a transmission electron microscope or a scanning electron microscope is 100 nm or less. It is a crystal.

  The luminescent nanocrystal particles can emit light (fluorescence or phosphorescence) having a wavelength different from the absorbed wavelength, for example, by absorbing light having a predetermined wavelength. The luminescent nanocrystal particles may be red luminescent nanocrystal particles that emit light (red light) having an emission peak wavelength in the range of 605 to 665 nm, and light having an emission peak wavelength in the range of 500 to 560 nm. It may be a green-emitting nanocrystal particle that emits (green light), or a blue-emitting nanocrystal particle that emits light (blue light) having an emission peak wavelength in the range of 420 to 480 nm. . In one embodiment, it is preferred that the ink composition comprises at least one of these luminescent nanocrystal particles. The light absorbed by the luminescent nanocrystal particles may be, for example, light having a wavelength in the range of 400 nm to less than 500 nm (blue light), or light having a wavelength in the range of 200 nm to 400 nm (ultraviolet light). The emission peak wavelength of the luminescent nanocrystal particles can be confirmed in, for example, a fluorescence spectrum or a phosphorescence spectrum measured using an ultraviolet-visible spectrophotometer.

  The red-emitting nanocrystal 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 The emission peak wavelength is preferably 632 nm or less or 630 nm or less, and the emission peak wavelength is 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 limit value and lower limit value can be arbitrarily combined. In addition, also in the following similar description, the individually described upper limit value and lower limit value can be arbitrarily combined.

  The green light-emitting nanocrystal particles have emission peak wavelengths at 560 nm or less, 557 nm or less, 555 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 is preferable to have an emission peak wavelength at 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.

  Blue-emitting nanocrystalline particles have a peak emission wavelength at 480 nm or less, 477 nm or less, 475 nm or less, 467 nm or less, 465 nm or less, 463 nm or less, 460 nm or less, 457 nm or less, 452 nm or less, or 450 nm or less. The emission peak wavelength is preferably 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 Schrodinger wave equation of the well-type potential model, the wavelength of light emitted from the luminescent nanocrystal particles depends on the size (for example, particle diameter) of the luminescent nanocrystal particles. It also depends on the energy gap of the crystal grains. Therefore, the luminescent color can be selected by changing the constituent material and size of the luminescent nanocrystal particles to be used.

  The luminescent nanocrystal particles may be luminescent nanocrystal particles (luminescent semiconductor nanocrystal particles) containing a semiconductor material. Examples of the luminescent semiconductor nanocrystal particles include quantum dots (hereinafter also referred to as “QD”), quantum rods, and the like. Among these, quantum dots are preferable from the viewpoints that the emission spectrum can be easily controlled and the reliability can be ensured, the production cost can be reduced, and the mass productivity can be improved.

  The luminescent semiconductor nanocrystal particle may be composed of only a core including a first semiconductor material, and includes a core including the first semiconductor material and a second semiconductor material different from the first semiconductor material, And a shell covering at least a part of the core. In other words, the structure of the luminescent semiconductor nanocrystal particles may be a structure consisting only of the core (core structure) or a structure consisting of the core and the shell (core / shell structure). The luminescent semiconductor nanocrystal particle includes a third semiconductor material different from the first and second semiconductor materials in addition to the shell including the second semiconductor material (first shell), You may have further the shell (2nd shell) which coat | covers at least one part. In other words, the structure of the luminescent semiconductor nanocrystal particles may be a structure (core / shell / shell structure) including a core, a first shell, and a second shell. Each of the core and the shell may be a mixed crystal including two or more kinds of semiconductor materials (for example, CdSe + CdS, CIS + ZnS, etc.).

  The luminescent nanocrystal particles are selected from the group consisting of II-VI semiconductors, III-V semiconductors, I-III-VI semiconductors, IV semiconductors and I-II-IV-VI semiconductors as semiconductor materials. It is preferable to include at least one kind of semiconductor material.

Specific semiconductor materials include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeTe, HgSeTe, HgSTe, Se. CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, CdHgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS InP, InAs, InSb, GaNP, GANAS, GaNSb, GaPAs, Ga Sb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAsIn, GaInNSB, GaInPAsInGa InAlPSb; SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe,
PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe; Si, Ge, SiC, SiGe, AgInSe 2, CuGaSe 2, CuInS 2, CuGaS 2, CuInSe 2, AgInS 2, AgGaSe 2, AgGaS 2, C, Si and Ge are mentioned. The luminescent semiconductor nanocrystal particles are easy to control the emission spectrum, and from the viewpoint of reducing production costs and improving mass productivity while ensuring reliability, CdS, CdSe, CdTe, ZnS, _{ZnSe, ZnTe, ZnO, HgS,} HgSe, HgTe, InP, InAs, InSb, GaP, GaAs, GaSb, AgInS 2, AgInSe 2, AgInTe 2, AgGaS 2, AgGaSe 2, AgGaTe 2, CuInS 2, CuInSe 2, CuInTe 2 It is preferable to contain at least one selected from the group consisting of CuGaS ₂ , CuGaSe ₂ , CuGaTe ₂ , Si, C, Ge, and Cu ₂ ZnSnS ₄ .

  Examples of the red light-emitting semiconductor nanocrystal particles include CdSe nanocrystal particles, CdSe rod-shaped nanocrystal particles, and rod-shaped nanocrystal particles having a core-shell structure, where the shell portion is CdS. Nanocrystalline particles having an inner core portion made of CdSe, rod-shaped nanocrystalline particles having a core-shell structure, wherein the shell portion is made of CdS and the inner core portion is made of ZnSe, a core-shell structure Nanocrystalline particles having a shell portion of CdS and an inner core portion of CdSe, and nanocrystalline particles having a core-shell structure, wherein the shell portion is CdS and the inner core portion , ZnSe nanocrystal particles, CdSe and ZnS mixed crystal nanocrystal particles, CdSe and ZnS mixed crystal rod-shaped nanocrystal particles, I P nanocrystal particles, InP nanocrystal particles, InP rod-like nanocrystal particles, mixed crystal nanocrystal particles of CdSe and CdS, mixed crystal rod-like nanocrystal particles of CdSe and CdS, ZnSe and Examples thereof include mixed crystal nanocrystal particles of CdS and mixed crystal rod-shaped nanocrystal particles of ZnSe and CdS.

  Examples of the green light emitting semiconductor nanocrystal particles include CdSe nanocrystal particles, CdSe rod-shaped nanocrystal particles, CdSe and ZnS mixed crystal nanocrystal particles, and CdSe and ZnS mixed crystal rod-shaped particles. And nanocrystal particles.

  Examples of blue light-emitting semiconductor nanocrystal particles include ZnSe nanocrystal particles, ZnSe rod-shaped nanocrystal particles, ZnS nanocrystal particles, ZnS rod-shaped nanocrystal particles, and nanocrystals having a core-shell structure. A nanocrystalline particle having a shell portion of ZnSe and an inner core portion of ZnS, and a rod-shaped nanocrystal having a core-shell structure, wherein the shell portion is ZnSe and the inner core portion is Examples thereof include nanocrystal particles of ZnS, CdS nanocrystal particles, and CdS rod-shaped nanocrystal particles. By changing the average particle diameter of the semiconductor nanocrystal particles with the same chemical composition, the color to be emitted from the particles can be changed to red or green. Further, as the semiconductor nanocrystal particles, it is preferable to use particles having 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, the semiconductor nanocrystal particles that do not contain the above elements (cadmium, selenium, etc.) as much as possible are selected and used alone, or the above elements It is preferable to use in combination with other luminescent nanocrystal particles so as to reduce as much as possible.

  The shape of the luminescent nanocrystal particles is not particularly limited, and may be any geometric shape or any irregular shape. The shape of the luminescent nanocrystal particles may be, for example, spherical, ellipsoidal, pyramidal, disc-shaped, branched, net-shaped, rod-shaped, or the like. However, as the luminescent nanocrystal particles, it is possible to further improve the uniformity and fluidity of the ink composition by using particles having less directionality (for example, spherical, tetrahedral, etc.). Is preferable.

  The average particle diameter (volume average diameter) of the luminescent nanocrystal particles may be 1 nm or more from the viewpoint that light emission at a desired wavelength is easily obtained and from the viewpoint of excellent dispersibility and storage stability. 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 nanocrystal particles is obtained by measuring with a transmission electron microscope or a scanning electron microscope and calculating the volume average diameter.

  The luminescent nanocrystal particles preferably have an organic ligand on the surface thereof from the viewpoint of dispersion stability. The organic ligand may be coordinated to the surface of the luminescent nanocrystal particle, for example. In other words, the surface of the luminescent nanocrystal particle may be passivated by the organic ligand. Moreover, the luminescent nanocrystal particle | grains may have a polymer dispersing agent on the surface. In one embodiment, for example, the organic dispersant is removed from the luminescent nanocrystal particles having the above-described organic ligand, and the organic dispersant and the polymer dispersant are exchanged, whereby the polymer dispersant is formed on the surface of the luminescent nanocrystal particle. May be combined. However, from the viewpoint of dispersion stability when an inkjet ink is used, it is preferable that a polymer dispersant is added to the luminescent nanocrystal particles in which the organic ligand is coordinated.

  Examples of the organic ligand include TOP (trioctylphosphine), TOPO (trioctylphosphine oxide), oleic acid, oleylamine, octylamine, trioctylamine, hexadecylamine, octanethiol, dodecanethiol, hexylphosphonic acid ( HPA), tetradecylphosphonic acid (TDPA), and octylphosphinic acid (OPA).

  As the luminescent nanocrystal particles, those dispersed in a colloidal form in an organic solvent, a photopolymerizable compound, or the like can be used. It is preferable that the surface of the luminescent nanocrystal particles dispersed in the organic solvent is passivated by the above-described organic ligand. Examples of the organic solvent include cyclohexane, hexane, heptane, chloroform, toluene, octane, chlorobenzene, tetralin, diphenyl ether, propylene glycol monomethyl ether acetate, butyl carbitol acetate, or a mixture thereof.

  A commercial item can be used as a luminescent nanocrystal particle. Examples of commercially available luminescent nanocrystal particles include indium phosphine / zinc sulfide, D-dot, CuInS / ZnS, and InP / ZnS from Aldrich, manufactured by NN-Labs.

  The content of the luminescent nanocrystal particles may be 5% by mass or more and 10% by mass or more based on the mass of the non-volatile content of the ink composition from the viewpoint of excellent leakage light reduction and light conversion efficiency. It may be 15 mass% or more, 20 mass% or more, 30 mass% or more, or 40 mass% or more. From the viewpoint of excellent ejection stability, the content of the luminescent nanocrystal particles may be 70% by mass or less, or 60% by mass or less, based on the mass of the nonvolatile content of the ink composition. The mass may be not more than 50% by mass or may be not more than 50% by mass. In the present specification, “the mass of the non-volatile content of the ink composition” refers to the mass obtained by subtracting the mass of the organic solvent from the total mass of the ink composition when the ink composition contains an organic solvent. When the product does not contain an organic solvent, it refers to the total mass of the ink composition.

  By the way, since the luminescent nanocrystal particle has a surface atom that can be a coordination site, it has high reactivity. Luminescent nanocrystal particles have such a high reactivity and a large surface area as compared with general pigments, and therefore easily cause aggregation of particles. Since the light-emitting nanocrystal particles emit light due to the quantum size effect, when the particles aggregate, a quenching phenomenon occurs, resulting in a decrease in the fluorescence quantum yield and a decrease in luminance and color reproducibility. On the other hand, in this embodiment, since the ink composition contains a polymer dispersant, the luminescent nanocrystal particles are difficult to aggregate. Therefore, in this embodiment, content of the luminescent nanocrystal particle can be made into the said range.

[Singlet oxygen quencher]
The singlet oxygen quencher used in the present invention will be described.

  Singlet oxygen is a kind of active oxygen having high reactivity, which is generated by exciting triplet oxygen in the ground state. This singlet oxygen is known to be inactivated by a singlet oxygen quencher (also called a quencher). By including these singlet oxygen quenchers in the ink of the present invention, when singlet oxygen is generated in the ink composition by light irradiation or the like, it can be inactivated.

As a singlet oxygen quencher in the present invention, for example,
(1) Nickel compound (2) Diimonium salt (3) DABCO (1,4-diazabicyclo [2.2.2] octane)
(4) Aniline compound (5) Luminol (6) Bilirubin (7) β-carotene (8) Furan compound and the like.

  Examples of the nickel compound include bis (dithiobenzyl) nickel (II), nickel p-toluenesulfonate (II), bis (1,2-benzenedithiolato) nickel (III) tetrabutylphosphonium, and nickel dibutyldithiocarbamate. As the diimonium salt (II), for example, the diimonium compound described in Asahi Glass Research Report Vol. 55, pp. 67-71, (2005), and the aniline compound include, for example, N, N, N ′, Examples of furan compounds such as N′-tetramethylphenylenediamine include 2,5-diphenylisobenzofuran.

From the viewpoint of solubility in organic solvents and photopolymerizable compounds, singlet oxygen quenchers are not carcinogenic or small,
(2) Diimonium salt (3) DABCO (1,4-diazabicyclo [2.2.2] octane)
(4) Aniline compound (5) Luminol (6) Bilirubin (7) β-carotene (8) A furan compound is more preferable.

Singlet oxygen quenchers, the reaction ease to quench singlet oxygen, for example, quenching rate constants can be represented by (reaction rate constant, also referred to as erasure rate constant) k _Q, it has been many reports. Simply referred to as a k a k _Q herein.

(For example, Francis Wilkinson, Journal of Physical and Chemical Reference Data, p 663-1021, Vol. 24, 1995. In this document, the extinction rate constants of a vast variety of compounds. In many cases, a plurality of data having different measurement conditions are described for each compound, and therefore, when referring to the above literature, the extinction rate constant k in the present invention is It shall represent the average value.)

In the present invention, from the viewpoint of inactivating singlet oxygen, a compound having a reaction rate constant k with singlet oxygen of 10 ⁷ M ⁻¹ s ⁻¹ or more is preferable. Moreover, it may be 10 ⁸ M ⁻¹ s ⁻¹ or more, and may be 10 ⁹ M ⁻¹ s ⁻¹ or more. Further, from the viewpoint of the stability of the singlet oxygen quencher, it may be 10 ¹² M ⁻¹ s ⁻¹ or less and may be 10 ¹¹ M ⁻¹ s ⁻¹ or less.

  The quenching rate constant can also be measured by the following method.

  That is, a method of competitively reacting 2,5-diphenyl-3,4-benzofuran (DPBF) and a quencher with singlet oxygen (hereinafter referred to as a competitive reaction method) is well known. Can be sought. This method is specifically described in Oreoscience magazine, Vol. 13, No. 8, p371-378, 2013 publication, and the quenching rate constant can be determined according to this method.

In the competitive reaction method, k can be obtained by the following equation (1).
Sblank / Sq = 1 + (k / kd) [Q] (1)

Here, Sblank is the slope of a primary reaction plot (a graph in which DPBF concentration (logarithmic display) decreases with time) of DPBF reduction due to singlet oxygen when no quencher is included, and Sq includes a quencher. In this case, the slope of a primary reaction plot (a graph in which the DPBF concentration (logarithmic display) decreases with respect to time) decreases in DPBF due to singlet oxygen, and [Q] indicates the quencher concentration. kd is a rate constant at which singlet oxygen is deactivated to triplet oxygen in a solvent. When a mixed solvent of ethanol: chloroform: heavy water (D ₂ O) = 50: 50: 1 (volume ratio) is used, kd is It is known to be 3.03 × 10 ⁵ s ⁻¹ .

  In the present invention, even when the reaction rate constant k is not known in the literature, it can be measured using the above method. According to the competitive reaction method, there is an advantage that DPBF can be quantified with a spectroscope that measures a very general and inexpensive visible light spectrum without requiring an expensive measuring device. In addition, the solvent at the time of measuring reaction rate can use the mixed solvent of said ethanol: chloroform: heavy water (D2O) = 50: 50: 1 (volume ratio). This solvent has an advantage that a wide range of materials can be evaluated because various materials from a hydrophobic compound to a hydrophilic compound can be dissolved. Further, as a method for generating singlet oxygen in the competitive reaction method, endoxides described in Oreoscience magazine, Vol. 13, No. 8, p. 371 to 378, 2013, can be used. Available from the company.

  The singlet oxygen quencher is a curing component to be described later, a photopolymerizable compound, a thermosetting resin, or an organic solvent that is used as necessary, by selecting and using at least one that is soluble, It is also preferable from the viewpoint of obtaining a uniform quenching effect in the ink composition.

In the present invention, the content of the singlet oxygen quencher in the ink composition is:
In terms of suppressing deterioration of the light conversion layer by ultraviolet rays or visible light, it may be 0.01% by mass or more, may be 0.1% by mass or more, and may be 0.5% by mass or more. It may be 1% by mass or more, and may be 30% by mass or less, 20% by mass or less, or 10% by mass or less from the viewpoint of avoiding coloring by a singlet oxygen quencher of the ink cured film. It may be 5% by mass or less.

[Light scattering particles]
The ink composition of one embodiment may contain light scattering particles. When a color filter pixel portion (hereinafter also simply referred to as a “pixel portion”) is formed from an ink composition using luminescent nanocrystal particles, light from the light source is not absorbed by the luminescent nanocrystal particles and the pixel portion. May leak. Since such leakage light reduces the color reproducibility of the pixel portion, when the pixel portion is used as the light conversion layer, it is preferable to reduce the leakage light as much as possible. The light scattering particles are preferably used in order to prevent leakage light from the pixel portion. The light scattering particles are, for example, optically inactive inorganic fine particles. The light scattering particles can scatter light from the light source irradiated to the color filter pixel portion.

  Examples of the material constituting the light scattering particles include 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, titanium oxide, 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, Metal carbonates such as barium carbonate, bismuth subcarbonate and calcium carbonate; metal hydroxides such as aluminum hydroxide; complex oxides such as barium zirconate, calcium zirconate, calcium titanate, barium titanate, strontium titanate, Bis nitrate Such as a metal salt of the scan, and the like. The light-scattering particles preferably include at least one selected from the group consisting of titanium oxide, alumina, zirconium oxide, zinc oxide, calcium carbonate, barium sulfate, and silica, from the viewpoint of being more effective in reducing leakage light. More preferably, it contains at least one selected from the group consisting of titanium oxide, barium sulfate and calcium carbonate.

  The shape of the light scattering particles may be spherical, filamentous, indeterminate. However, as the light scattering particles, it is possible to use particles having less directivity as the particle shape (for example, spherical, tetrahedral, etc. particles), thereby improving the uniformity, fluidity and light scattering of the ink composition. It is preferable in that it can be improved.

  The average particle diameter (volume average diameter) of the light-scattering particles in the ink composition may be 0.05 μm or more, or 0.2 μm or more, from the viewpoint of being excellent in the effect of reducing leakage light. It may be 0.3 μm or more. The average particle diameter (volume average diameter) of the light-scattering particles in the ink composition may be 1.0 μm or less, 0.6 μm or less, from the viewpoint of excellent ejection stability. It may be 4 μm 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, and 0.2 to 1. It may be 0.0 μm, 0.2 to 0.6 μm, 0.2 to 0.4 μm, 0.3 to 1.0 μm, 0.3 to 0.6 μm, or 0.3 to 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 50 nm or more and 1000 nm or less. The average particle diameter (volume average diameter) of the light-scattering particles is obtained by measuring with a dynamic light scattering nanotrack particle size distribution meter and calculating the volume average diameter. The average particle diameter (volume average diameter) of the light-scattering particles used is obtained by measuring the particle diameter of each particle with, for example, a transmission electron microscope or a scanning electron microscope and calculating the volume average diameter.

  The content of the light-scattering particles may be 0.1% by mass or more based on the non-volatile content of the ink composition, and may be 1% by mass or more from the viewpoint of being excellent in the effect of reducing leakage light. Alternatively, it may be 5% by mass or more, 7% by mass or more, 10% by mass or more, or 12% by mass or more. The content of the light-scattering particles may be 60% by mass or less and 50% by mass based on the mass of the non-volatile content of the ink composition from the viewpoint of being excellent in the effect of reducing leakage light and excellent in ejection stability. Or 40% by mass or less, 30% by mass or less, 25% by mass or less, 20% by mass or less, or 15% by mass. It may be the following. In this embodiment, since the ink composition contains a polymer dispersant, the light scattering particles can be favorably dispersed even when the content of the light scattering particles is within the above range.

The mass ratio of the content of the light scattering particles to the content of the light emitting nanocrystal particles (light scattering particles / light emitting nanocrystal particles) is 0.1 to 5.0. The mass ratio (light-scattering particles / light-emitting nanocrystal particles) may be 0.2 or more or 0.5 or more from the viewpoint of excellent leakage light reduction effect. The mass ratio (light scattering particles / luminescent nanocrystal particles) may be 2.0 or less, or 1.5 or less from the viewpoint of excellent leakage light reduction effect and excellent continuous discharge properties during ink jet printing. It may be. The mass ratios (light scattering particles / luminescent nanocrystal particles) are 0.1 to 2.0, 0.1 to 1.5, 0.2 to 5.0, 0.2 to 2.0, 0.0. It may be 2 to 1.5, 0.5 to 5.0, 0.5 to 2.0, or 0.5 to 1.5. In addition, it is thought that leakage light reduction by light-scattering particles is based on the following mechanism. That is, when no light-scattering particles are present, it is considered that the backlight light only passes almost straight through the pixel portion and is less likely to be absorbed by the light-emitting nanocrystal particles. On the other hand, if the light-scattering particles are present in the same pixel portion as the light-emitting nanocrystal particles, the backlight light is scattered in all directions in the pixel portion, and the light-emitting nanocrystal particles can receive it. Even if the same backlight is used, it is considered that the light absorption amount in the pixel portion increases. As a result, it is considered that leakage light can be prevented by such a mechanism.

[Polymer dispersant]
The ink composition of one embodiment preferably contains a polymer dispersant. The polymer dispersant can uniformly disperse the light scattering particles in the ink.

  In the present invention, the polymer dispersant is a polymer compound having a weight average molecular weight of 750 or more and having a functional group having an affinity for the light scattering particles, and the function of dispersing the light scattering particles. Have The polymer dispersant is adsorbed to the light-scattering particles through a functional group having an affinity for the light-scattering particles, and electrostatic and / or steric repulsion between the polymer dispersants. Light scattering particles are dispersed in the ink composition. The polymer dispersant is preferably bonded to the surface of the light-scattering particle and adsorbed to the light-scattering particle, but is bonded to the surface of the light-emitting nanocrystal particle and adsorbed to the light-emitting nanoparticle. It may be free in the ink composition.

  Examples of the functional group having an affinity for the light-scattering particles include an acidic functional group, a basic functional group, and a nonionic functional group. The acidic functional group has a dissociable proton and may be neutralized with a base such as amine or hydroxide ion, and the basic functional group is neutralized with an acid such as organic acid or inorganic acid. May be.

Examples of the acidic functional group include a carboxyl group (—COOH), a sulfo group (—SO ₃ H), a sulfuric acid group (—OSO ₃ H), a phosphonic acid group (—PO (OH) ₃ ), and a phosphoric acid group (—OPO ( OH) ₃ ), a phosphinic acid group (—PO (OH) —), and a mercapto group (—SH).

Examples of 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 (—SO ₂ —), carbonyl group, formyl group, ester group, carbonate group, amide group, Examples include carbamoyl group, ureido group, thioamide group, thioureido group, sulfamoyl group, cyano group, alkenyl group, alkynyl group, phosphine oxide group, and phosphine sulfide group.

  From the viewpoint of dispersion stability of light-scattering particles, from the viewpoint of hardly causing the side effect that the luminescent nanocrystal particles settle, from the viewpoint of ease of synthesis of the polymer dispersant, and from the viewpoint of stability of the functional group, acidic functional As the group, a carboxyl group, a sulfo group, a phosphonic acid group, and a phosphoric acid group are preferably used, and as the basic functional group, an amino group is preferably used. Among these, a carboxyl group, a phosphonic acid group, and an amino group are more preferably used, and most preferably an amino group is used.

  The polymer dispersant having an acidic functional group has an acid value. The acid value of the polymer dispersant having an acidic functional group is preferably 1 to 150 mgKOH / g in terms of solid content. When the acid value is 1 or more, sufficient dispersibility of the light-scattering particles can be easily obtained, and when the acid value is 150 or less, the storage stability of the pixel portion (cured product of the ink composition) is hardly lowered. .

  In addition, the polymer dispersant having a basic functional group has an amine value. The amine value of the polymer dispersant having a basic functional group is preferably 1 to 200 mgKOH / g in terms of solid content. When the amine value is 1 or more, sufficient dispersibility of the light-scattering particles can be easily obtained, and when the amine value is 200 or less, the storage stability of the pixel portion (cured product of the ink composition) is hardly lowered. .

  The polymer dispersant may be a polymer (homopolymer) of a single monomer, or may be a copolymer (copolymer) of a plurality of types of monomers. The polymer dispersant may be any of a random copolymer, a block copolymer, or a graft copolymer. When the polymer dispersant is a graft copolymer, it may be a comb-shaped graft copolymer or a star-shaped graft copolymer. Polymer dispersants include, for example, acrylic resins, polyester resins, polyurethane resins, polyamide resins, polyethers, phenol resins, silicone resins, polyurea resins, amino resins, polyethylamines and other polyamines, epoxy resins, polyimides, etc. It may be.

  Commercially available products can also be used as the polymer dispersant, and examples of commercially available products include Ajinomoto Fine Techno Co., Ltd. Ajisper PB series, BYK's DISPERBYK series and BYK- series, BASF's Efka series. Etc. can be used.

Commercially available products include, for example, “DISPERBYK-130”, “DISPERBYK-161”, “DISPERBYK-162”, “DISPERBYK-163”, “DISPERBYK-164”, “DISPERBYK-166”, “DISPERBYK-” manufactured by Big Chemie. 167 "," DISPERBYK-168 "," DISPERBYK-170 "," DISPERBYK-171 "," DISPERBYK-174 "," DISPERBYK-180 "," DISPERBYK-182 "," DISPERBYK-183 "," DISPERBYK-184 " , “DISPERBYK-185”, “DISPERBYK-2000”, “DISPERBYK-2001”, “DISPERBYK-2008”, “DISP” RBYK-2009 "," DISPERBYK-2020 "," DISPERBYK-2022 "," DISPERBYK-2025 "," DISPERBYK-2050 "," DISPERBYK-2070 "," DISPERBYK-2096 "," DISPERBYK-2150 "," DISPERBY " 2155 "," DISPERBYK-2163 "," DISPERBYK-2164 "," BYK-LPN21116 "and" BYK-LPN6919 ";" EFKA4010 "," EFKA4015 "," EFKA4046 "," EFKA4047 "," EFK "manufactured by BASF , “EFKA4080”, “EFKA4300”, “EFKA4310”, “EFKA4320”, “EFKA4330”, “EFK” "4340", "EFKA4560", "EFKA4585", "EFKA5207", "EFKA1501", "EFKA1502", "EFKA1503" and "EFKA PX-4701";"Solsparse3000","Solsparse9000","Lubrisol""Sol Sparse 13240", "Sol Sparse 13650", "Sol Sparse 13940", "Sol Sparse 11200", "Sol Sparse 13940", "Sol Sparse 16000", "Sol Sparse 17000", "Sol Sparse 18000", "Sol Sparse 20000", "Sol Sparse 21000", ""Sol Sparse 24000", "Sol Sparse 26000", "Sol Sparse 27000", "Sol Sparse 28000", "Sol Sparse 32000" “Sol Sparse 32500”, “Sol Sparse 32550”, “Sol Sparse 32600”, “Sol Sparse 33000”, “Sol Sparse 34750”, “Sol Sparse 35100”, “Sol Sparse 35200”, “Sol Sparse 36000”, “Sol Sparse 37500”, “Sol Sparse 38500”, "Solsparth 39000", "Solsparth 41000", "Solsperse 54000", "Solsperse 71000" and "Solsperse 76500";"AjisperPB821","AzisperPB882","AzisperPB881","PN411" manufactured by Ajinomoto Fine Techno Co., Ltd. And "PA
111 ”;“ TEGO Dispers 650 ”,“ TEGO Dispers 662C ”,“ TEGO Dispers 670 ”,“ TEGO Dispers 685 ”,“ TE ”700 and“ TEO Dispers 685 ”,“ TE ”700 and“ TEO Dispers 685 ”. “Disparon DA-703-50”, “DA-705”, “DA-725” and the like can be used.

  As the polymer dispersant, in addition to the above-mentioned commercially available products, a cationic monomer containing a basic group and / or an anionic monomer having an acidic group, a monomer having a hydrophobic group, and other monomers if necessary Those synthesized by copolymerizing (nonionic monomers, monomers having a hydrophilic group, etc.) can be used. As for details of the cationic monomer, the anionic monomer, the monomer having a hydrophobic group, and other monomers, there can be mentioned monomers described in paragraphs 0034 to 0036 of JP-A No. 2004-250502.

  Further, for example, a compound obtained by reacting a polyalkyleneimine and a polyester compound described in JP-A-54-37082, JP-A-61-174939, or the like, or a polyallylamine described in JP-A-9-169821 A compound in which the amino group of the side chain is modified with polyester, a graft polymer having a polyester type macromonomer described in JP-A-9-171253 as a copolymerization component, and a polyester polyol addition described in JP-A-60-166318 Preferred examples include polyurethane.

  The weight average molecular weight of the polymer dispersant may be 750 or more and 1000 or more from the viewpoint of being able to favorably disperse the light-scattering particles and further improve the effect of reducing leakage light. It may be 2000 or more and 3000 or more. The weight average molecular weight of the polymer dispersant can disperse the light-scattering particles satisfactorily, can further improve the leakage light reduction effect, and can discharge the viscosity of the inkjet ink and is suitable for stable discharge. From the viewpoint of viscosity, it may be 100,000 or less, 50000 or less, or 30000 or less. In the present specification, the weight average molecular weight is a weight average molecular weight in terms of polystyrene measured by GPC (gel permeation chromatography).

  From the viewpoint of dispersibility of the light-scattering particles, the content of the polymer dispersant may be 0.5 parts by mass or more with respect to 100 parts by mass of the light-scattering particles, It may be 5 parts by mass or more. The content of the polymer dispersion may be 50 parts by mass or less and 30 parts by mass or less with respect to 100 parts by mass of the light-scattering particles from the viewpoint of wet heat stability of the pixel part (cured product of the ink composition). It may be 10 parts by mass or less.

[Curing component]
The curing component of this embodiment is a photopolymerizable compound and / or a thermosetting resin.

[Photopolymerizable compound]
The photopolymerizable compound of this embodiment is a photoradical polymerizable compound or a photocationic polymerizable compound that is polymerized by light irradiation, and may be a photopolymerizable monomer or oligomer. These are used together with a photopolymerization initiator. The photoradical polymerizable compound is used with a photoradical polymerization initiator, and the photocationic polymerizable compound is used with a photocationic polymerization initiator. In other words, the ink composition may contain a photopolymerizable component containing a photopolymerizable compound and a photopolymerization initiator, and contains a photoradical polymerizable component containing a photoradical polymerizable compound and a photoradical polymerization initiator. The photocationic polymerizable component containing a photocationic polymerizable compound and a photocationic polymerization initiator may be contained. A photo radical polymerizable compound and a photo cationic polymerizable compound may be used in combination, or a compound having a photo radical polymerizable property and a photo cationic polymerizable property may be used. A photo radical polymerization initiator, a photo cationic polymerization initiator, May be used in combination. A photopolymerizable compound may be used individually by 1 type, and may use 2 or more types together.

  Examples of the radical photopolymerizable compound include (meth) acrylate compounds. The (meth) acrylate compound may be a monofunctional (meth) acrylate having one (meth) acryloyl group or a polyfunctional (meth) acrylate having a plurality of (meth) acryloyl groups. Monofunctional (meth) acrylate and polyfunctional (meta) from the viewpoint of excellent fluidity when used in ink, excellent viewpoint of ejection stability, and suppression of smoothness deterioration due to curing shrinkage during color filter production. ) Acrylate is preferably used in combination. In the present specification, (meth) acrylate means “acrylate” and “methacrylate” corresponding thereto. The same applies to the expression “(meth) acryloyl”.

  Examples of monofunctional (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, amyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and octyl. (Meth) acrylate, nonyl (meth) acrylate, dodecyl (meth) acrylate, hexadecyl (meth) acrylate, octadecyl (meth) acrylate, cyclohexyl (meth) acrylate, methoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, phenoxy Ethyl (meth) acrylate, nonylphenoxyethyl (meth) acrylate, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (Meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 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, succinic acid mono (2-acryloyloxyethyl), N- [2- (acryloyloxy) ) Ethyl] phthalimide, N- [2- (acryloyloxy) ethyl] tetrahydrophthalimide, and the like.

  The polyfunctional (meth) acrylate may be bifunctional (meth) acrylate, trifunctional (meth) acrylate, tetrafunctional (meth) acrylate, pentafunctional (meth) acrylate, hexafunctional (meth) acrylate, etc. Di (meth) acrylate in which two hydroxyl groups of diol compound are substituted by (meth) acryloyloxy group, di or tri (meth) acrylate in which two or three hydroxyl groups of triol compound are substituted by (meth) acryloyloxy group Etc.

Specific examples of the bifunctional (meth) acrylate include 1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,5-pentanediol di (meth) acrylate, 3- Methyl-1,5-pentanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,8-octanediol di (meth) acrylate, 1,9 -Nonanediol di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) ) Acrylate, The two hydroxyl groups of propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol hydroxypivalate ester diacrylate, and tris (2-hydroxyethyl) isocyanurate are (meth) acryloyl. Di (meth) acrylate substituted with an oxy group, dipentaglycol in which two hydroxyl groups of a diol obtained by adding 4 mol or more of ethylene oxide or propylene oxide to 1 mol of neopentyl glycol are substituted with a (meth) acryloyloxy group (Meth) acrylate, di (me) in which two hydroxyl groups of a diol obtained by adding 2 moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A are substituted with (meth) acryloyloxy groups. ) Di (meth) acrylate in which two hydroxyl groups of triol obtained by adding 3 mol or more of ethylene oxide or propylene oxide to 1 mol of acrylate and trimethylolpropane are substituted by (meth) acryloyloxy group in 1 mol of bisphenol A Examples thereof include di (meth) acrylate in which two hydroxyl groups of a diol obtained by adding 4 mol or more of ethylene oxide or propylene oxide are substituted with a (meth) acryloyloxy group.

  Specific examples of trifunctional (meth) acrylates include trimethylolpropane tri (meth) acrylate, glycerin triacrylate, pentaerythritol tri (meth) acrylate, and 3 mol or more of ethylene oxide or propylene oxide added to 1 mol of trimethylolpropane. And tri (meth) acrylate in which the three hydroxyl groups of the triol obtained are substituted with a (meth) acryloyloxy group.

  Specific examples of the tetrafunctional (meth) acrylate include pentaerythritol tetra (meth) acrylate.

  Specific examples of the pentafunctional (meth) acrylate include dipentaerythritol penta (meth) acrylate.

  Specific examples of the hexafunctional (meth) acrylate include dipentaerythritol hexa (meth) acrylate.

  The polyfunctional (meth) acrylate may be a poly (meth) acrylate in which a plurality of hydroxyl groups of dipentaerythritol such as dipentaerythritol hexa (meth) acrylate are substituted with (meth) acryloyloxy groups.

  The (meth) acrylate compound may be a phosphoric acid group-containing ethylene oxide-modified phosphoric acid (meth) acrylate, ethylene oxide-modified alkyl phosphoric acid (meth) acrylate, or the like.

  Examples of the cationic photopolymerizable compound include an epoxy compound, an oxetane compound, and a vinyl ether compound.

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

  It is also possible to use a commercial item as an epoxy compound. Examples of commercially available epoxy compounds include “Celoxide 2000”, “Celoxide 3000”, and “Celoxide 4000” manufactured by Daicel Chemical Industries, Ltd.

  Examples of the cationically polymerizable oxetane compound include 2-ethylhexyloxetane, 3-hydroxymethyl-3-methyloxetane, 3-hydroxymethyl-3-ethyloxetane, 3-hydroxymethyl-3-propyloxetane, and 3-hydroxymethyl-3. Normal butyl oxetane, 3-hydroxymethyl-3-phenyl oxetane, 3-hydroxymethyl-3-benzyl oxetane, 3-hydroxyethyl-3-methyl oxetane, 3-hydroxyethyl-3-ethyl oxetane, 3-hydroxyethyl- 3-propyloxetane, 3-hydroxyethyl-3-phenyloxetane, 3-hydroxypropyl-3-methyloxetane, 3-hydroxypropyl-3-ethyloxetane, 3-hydroxypropyl-3-propyloxeta , 3-hydroxypropyl-3-phenyl oxetane, 3-hydroxybutyl-3-methyl oxetane, and the like.

  Commercial products can be used as the oxetane compound. Examples of commercially available oxetane compounds include Aron Oxetane series (“OXT-101”, “OXT-212”, “OXT-121”, “OXT-221”, etc.) manufactured by Toa Gosei Co., Ltd.); “Celoxide 2021”, “Celoxide 2021A”, “Celoxide 2021P”, “Celoxide 2080”, “Celoxide 2081”, “Celoxide 2083”, “Celoxide 2085”, “Epolide GT300”, “Epolide GT301”, “Epolide GT302”, “Epolide GT400”, “Epolide GT401” and “Epolide GT403”; “Syracure UVR-6105”, “Syracure UVR-6107”, “Syracure UVR-6110” manufactured by Dow Chemical Japan Co., Ltd. , And the like can be used "CYRACURE UVR-6128", "ERL4289" and "ERL4299". Moreover, a well-known oxetane compound (For example, the oxetane compound as described in Unexamined-Japanese-Patent No. 2009-40830 etc.) can also be used.

  Examples of the vinyl ether compound include 2-hydroxyethyl vinyl ether, triethylene glycol vinyl monoether, tetraethylene glycol divinyl ether, trimethylolpropane trivinyl ether, and the like.

  In addition, as the photopolymerizable compound in the present embodiment, the photopolymerizable compounds described in paragraphs 0042 to 0049 of JP2013-182215A can also be used.

  In the ink composition of the present embodiment, when the curable component is composed of only a photopolymerizable compound or a main component thereof, the above-described photopolymerizable compound has a polymerizable functional group in one molecule. It is more preferable to use a bifunctional or higher polyfunctional photopolymerizable compound having 2 or more as an essential component because durability (strength, heat resistance, etc.) of the cured product can be further improved.

  The photopolymerizable compound may be insoluble in alkali from the viewpoint of easily obtaining a color filter pixel portion having excellent reliability. In the present specification, the photopolymerizable compound is 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. It means that it is below mass%. The dissolution amount of the photopolymerizable compound is preferably 10% by mass or less, and more preferably 3% by mass or less.

  The content of the photopolymerizable compound is the viewpoint that an appropriate viscosity is easily obtained as an inkjet ink, the viewpoint that the curability of the ink composition is good, and the solvent resistance of the pixel portion (cured product of the ink composition). From the viewpoint of improving the wear resistance, it may be 10% by mass or more, 15% by mass or more, or 20% by mass or more based on the mass of the nonvolatile content of the ink composition. The content of the photopolymerizable compound is based on the mass of the non-volatile content of the ink composition from the viewpoint of easily obtaining an appropriate viscosity as an inkjet ink, and from the viewpoint of obtaining more excellent optical characteristics (leakage light). It may be 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, or 50% by mass or less.

  The photopolymerizable compound has a crosslinkable group from the viewpoint of excellent stability of the pixel portion (cured product of the ink composition) (for example, it can suppress deterioration over time and is excellent in high-temperature storage stability and wet heat storage stability). You may do it. The crosslinkable group is a functional group that reacts with other crosslinkable groups by heat or active energy rays (for example, ultraviolet rays), such as an epoxy group, an oxetane group, a vinyl group, an acryloyl group, an acryloyloxy group, and a vinyl ether group. Is mentioned.

[Photo radical polymerization initiator]
As the radical photopolymerization initiator, a molecular cleavage type or hydrogen abstraction type radical photopolymerization initiator is suitable.

  Examples of the molecular cleavage type photo radical polymerization initiator include benzoin isobutyl ether, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-benzyl-2-dimethylamino- 1- (4-morpholinophenyl) -butan-1-one, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, (2,4,6-trimethylbenzoyl) ethoxyphenyl Phosphine oxide and the like are preferably used. Other molecular cleavage type photo radical polymerization initiators include 1-hydroxycyclohexyl phenyl 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.

  Examples of the hydrogen abstraction type photo radical polymerization initiator include benzophenone, 4-phenylbenzophenone, isophthalphenone, 4-benzoyl-4'-methyl-diphenyl sulfide, and the like. A molecular cleavage type photo radical polymerization initiator and a hydrogen abstraction type photo radical polymerization initiator may be used in combination.

[Photocationic polymerization initiator]
Examples of the cationic photopolymerization initiator include polyarylsulfonium salts such as triphenylsulfonium hexafluoroantimonate and triphenylsulfonium hexafluorophosphate; diphenyliodonium hexafluoroantimonate, P-nonylphenyliodonium hexafluoroantimony Examples thereof include polyaryl iodonium salts such as nates.

  A commercial item 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", "Irgacure PAG290", etc. are mentioned.

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

[Thermosetting resin]
In the present embodiment, the thermosetting resin is a resin that functions as a binder in a cured product and is crosslinked and cured by heat. The thermosetting resin has a curable group. Examples of the curable group include an epoxy group, an oxetane group, an isocyanate group, an amino group, a carboxyl group, a methylol group, and the like, from the viewpoint of excellent heat resistance and storage stability of a cured product of the ink composition, and a light shielding part ( For example, an epoxy group is preferable from the viewpoint of excellent adhesion to a black matrix and a substrate. The thermosetting resin may have one type of curable group or may have two or more types of curable groups.

  Among thermosetting resins, there are resins having photo-radical polymerizability (polymerized by light irradiation when used together with photo-radical polymerization initiator) and photo-cationic polymerizability (photocationic polymerization). Resin that polymerizes when irradiated with light when used with an initiator. When the ink composition contains a thermosetting resin having photoradical polymerizability and a photoradical polymerization initiator, the thermosetting resin having photoradical polymerizability is converted into a photoradical polymerizable compound (photopolymerizable compound). Shall be classified. When the ink composition contains a thermosetting resin having a photocationic polymerization property and a photocationic polymerization initiator, the thermosetting resin having the photocationic polymerization property is converted into a photocationic polymerizable compound (photopolymerizable compound). Shall be classified.

  The thermosetting resin may be a polymer (homopolymer) of a single monomer, or may be a copolymer (copolymer) of a plurality of types of monomers. Further, the thermosetting resin may be any of a random copolymer, a block copolymer, or a graft copolymer.

  As the thermosetting resin, a compound having two or more thermosetting functional groups in one molecule is used, and it is usually used in combination with a curing agent. When using a thermosetting resin, you may further add the catalyst (curing accelerator) which can accelerate | stimulate a thermosetting reaction. In other words, the ink composition may contain a thermosetting component including a thermosetting resin (and a curing agent and a curing accelerator used as necessary). In addition to these, a polymer having no polymerization reactivity per se may be further used.

  As a compound having two or more thermosetting functional groups in one molecule, for example, an epoxy resin having two or more epoxy groups in one molecule (hereinafter also referred to as “polyfunctional epoxy resin”) may be used. “Epoxy resin” includes both monomeric epoxy resins and polymeric epoxy resins. The number of epoxy groups contained in one molecule of the polyfunctional epoxy resin is preferably 2 to 50, and more preferably 2 to 20. The epoxy group may be a structure having an oxirane ring structure, and may be a glycidyl group, an oxyethylene group, an epoxycyclohexyl group, or the like. As an epoxy resin, the well-known polyvalent epoxy resin which can be hardened | cured with carboxylic acid can be mentioned. Such epoxy resins are widely disclosed in, for example, published by Masaki Shinbo, “Epoxy Resin Handbook” published by Nikkan Kogyo Shimbun (1987), and these can be used.

  Examples of the thermosetting resin having an epoxy group (including a polyfunctional epoxy resin) include a polymer of a monomer having an oxirane ring structure, and a copolymer of a monomer having an oxirane ring structure and another monomer. Examples of the monomer include various epoxy group-containing monomers such as glycidyl (meth) acrylate, β-methylglycidyl (meth) acrylate, glycidyl vinyl ether, and allyl glycidyl ether; (2-oxo-1,3-oxolane) ) (2-oxo-1,3-oxolane) group-containing vinyl monomers such as methyl (meth) acrylate; 3,4-epoxycyclohexyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate And various alicyclic epoxy group-containing vinyl monomers such as 3,4-epoxycyclohexylethyl (meth) acrylate.

  On the other hand, as the ethylenically unsaturated double bond-containing monomer, for example, various aromatic vinyls such as styrene, α-methylstyrene, vinyltoluene; methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, Various acrylic esters; various methacrylate esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate; ethylene, propylene, butene-1 Various α-olefins such as: Various halogenated olefins (halo-olefins) other than fluoroolefins such as vinyl chloride and vinylidene chloride; Dimethyl fumarate, Various unsaturations such as diethyl malate, dibutyl fumarate, dioctyl fumarate, dimethyl maleate, diethyl maleate, dibutyl maleate, dioctyl maleate, dimethyl itaconate, diethyl itaconate, dibutyl itaconate, dioctyl itaconate Diesters of dicarboxylic acids and monohydric alcohols having 1 to 18 carbon atoms; vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl caproate, vinyl caprylate, vinyl caprate, vinyl laurate, carbon Various branched (branched) aliphatic carboxylates having 9 atoms, branched aliphatic carboxylates having 10 carbon atoms, branched aliphatic carboxylates having 11 carbon atoms, vinyl stearates, and the like. Aliphatic vinyl carboxylates and the like can be mentioned.

  Specific polyfunctional epoxy resins include polyglycidyl methacrylate, methyl methacrylate-glycidyl methacrylate copolymer, benzyl methacrylate-glycidyl methacrylate copolymer, n-butyl methacrylate-glycidyl methacrylate copolymer, 2-hydroxyethyl methacrylate-glycidyl. Examples thereof include a methacrylate copolymer, (3-ethyl-3-oxetanyl) methyl methacrylate-glycidyl methacrylate copolymer, and styrene-glycidyl methacrylate. In addition, as the thermosetting resin of the present embodiment, compounds described in paragraphs 0044 to 0066 of JP-A-2014-56248 can also be used.

  A homopolymer or copolymer of a monomer having such an oxirane ring structure is preferably a two-dimensional (linear) copolymer from the viewpoint of ease of handling and production. For example, without a solvent Or in organic solvents, glycidyl (meth) acrylate as an essential component, ethylenically unsaturated monomers such as aromatic vinyl and (meth) acrylic acid esters, which are known and commonly used copolymerizable ethylenically unsaturated monomers It can be obtained by polymerizing together a monomer containing one double bond and, if necessary, a monomer containing two or more ethylenically unsaturated double bonds. By adjusting the combined ratio of glycidyl (meth) acrylate and other ethylenically unsaturated monomers, a copolymer having a desired epoxy group content can be obtained, or a copolymerizable ethylenically unsaturated monomer can be obtained. Depending on what kind of polymer is selected and used or how much the average molecular weight of the copolymer is, the refractive index of the copolymer, glass transition temperature, flexibility, transparency, solubility in organic solvents, etc. Can be adjusted. The copolymerization ratio of a monomer containing an aromatic ring such as aromatic vinyl is, for example, the refractive index of the produced copolymer, the alkyl chain length of (meth) acrylate is the flexibility of the produced copolymer and the support Affects adhesion to etc. Such a copolymer can be used, for example, in an organic solvent so that the glycidyl group does not ring-open with a known and commonly copolymerizable ethylenically unsaturated monomer having the glycidyl (meth) acrylate as an essential component. It can also be easily obtained by performing polymerization until the desired molecular weight is achieved.

  Examples of the polyfunctional epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol S type epoxy resin, diphenyl ether type epoxy resin, hydroquinone type epoxy resin, and naphthalene type epoxy. Resin, biphenyl type epoxy resin, fluorene type epoxy resin, phenol novolac type epoxy resin, orthocresol novolac type epoxy resin, trishydroxyphenylmethane type epoxy resin, trifunctional type epoxy resin, tetraphenylolethane type epoxy resin, dicyclopentadiene Phenol type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol A nucleated polyol type epoxy resin, polypropylene glycol type epoxy Fat, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, glyoxal type epoxy resins, alicyclic epoxy resins, and the like heterocyclic epoxy resin.

  More specifically, bisphenol A type epoxy resins such as trade name “Epicoat 828” (manufactured by Japan Epoxy Resin), bisphenol F type epoxy resins such as trade name “YDF-175S” (manufactured by Toto Kasei), Brominated bisphenol A type epoxy resin such as “YDB-715” (manufactured by Toto Kasei Co., Ltd.), bisphenol S type epoxy resin such as “EPICLON EXA1514” (manufactured by DIC Corporation), product name “YDC-1312” ( Hydroquinone type epoxy resins such as Toto Kasei Co., Ltd., and naphthalene type epoxy resins such as trade names “EPICLON EXA4032”, “HP-4770”, “HP-4700”, “HP-5000” (manufactured by DIC Corporation), Product name "Epicoat YX4000H" (manufactured by Japan Epoxy Resin Co., Ltd.) Biphenyl type epoxy resin, bisphenol A type novolak epoxy resin such as trade name “Epicoat 157S70” (made by Japan Epoxy Resin), trade name “Epicoat 154” (made by Japan Epoxy Resin), trade name “YDPN-638” ( Phenol novolac type epoxy resins such as Toto Kasei Co., Ltd., cresol novolac type epoxy resins such as trade name “YDCN-701” (manufactured by Toto Kasei Co., Ltd.), trade names “EPICLON HP-7200”, “HP-7200H” (DIC) Dicyclopentadiene phenol type epoxy resin such as “Epicoat 1032H60” (manufactured by Japan Epoxy Resin Co., Ltd.), trade name “VG3101M80” (manufactured by Mitsui Chemicals), etc. Three officials Type epoxy resin, tetraphenylolethane type epoxy resin such as trade name “Epicoat 1031S” (manufactured by Japan Epoxy Resin Co., Ltd.), tetrafunctional type epoxy resin such as trade name “Denacol EX-411” (manufactured by Nagase Chemical Industries), Hydrogenated bisphenol A type epoxy resin such as trade name “ST-3000” (manufactured by Toto Kasei), glycidyl ester type epoxy resin such as trade name “Epicoat 190P” (made by Japan Epoxy Resin), trade name “YH-434” ”(Manufactured by Tohto Kasei Co., Ltd.), glycidyl amine type epoxy resin such as“ YDG-414 ”(manufactured by Tohto Kasei Co., Ltd.), and the product name“ Epolide GT-401 ”(manufactured by Daicel Chemical Industries). Alicyclic polyfunctional epoxy compounds, triglycidyl isocyanate (TGIC), etc. Heterocyclic epoxy resin and the like can be exemplified. Further, if necessary, a trade name “Neoto Tote E” (manufactured by Tohto Kasei Co., Ltd.) or the like can be mixed as an epoxy reactive diluent.

  In addition, as the polyfunctional epoxy resin, “Fine Dick A-247S”, “Fine Dick A-254”, “Fine Dick A-253”, “Fine Dick A-229-30A” manufactured by DIC Corporation, “ "Fine Dick A-261", "Fine Dick A249", "Fine Dick A-266", "Fine Dick A-241", "Fine Dick M-8020", "Epicron N-740", "Epicron N-770", “Epiclon N-865” (trade name) or the like can be used.

  When a polyfunctional epoxy resin having a relatively low molecular weight is used as the thermosetting resin, the epoxy group is replenished in the ink composition (inkjet ink) to increase the concentration of epoxy reactive sites and increase the crosslinking density. it can.

  Among the polyfunctional epoxy resins, from the viewpoint of increasing the crosslink density, it is preferable to use an epoxy resin having four or more epoxy groups in one molecule (polyfunctional epoxy resin having four or more functions). In particular, when a thermosetting resin having a weight average molecular weight of 10,000 or less is used in order to improve the ejection stability from the ejection head in the ink jet system, the strength and hardness of the pixel portion (cured product of the ink composition) is reduced. From the viewpoint of sufficiently increasing the crosslink density, it is preferable to blend a polyfunctional epoxy resin having 4 or more functionalities into the ink composition (inkjet ink).

  As a thermosetting resin having an epoxy group, a multi-component copolymer of a monomer having an oxirane ring structure and another monomer is excellent in transparency and transparency, and is excellent in chemical resistance and flexibility. From the viewpoint of easily obtaining a cured product having the above advantages, it is preferable compared to other polyfunctional epoxy resins. Such excellent optical properties and film properties as a cured product indicate that it is suitable for use in, for example, optical material applications, particularly in light conversion layers where long-term reliability is expected.

  As the curing agent and curing accelerator used for curing the thermosetting resin, any known and commonly used one that can be dissolved or dispersed in an organic solvent can be used. For example, 4-methyl Hexahydrophthalic anhydride, triethylenetetramine, diaminodiphenylmethane, phenol novolac resin, tris (dimethylaminomethyl) phenol, N, N-dimethylbenzylamine, 2-ethyl-4-methylimidazole, triphenylphosphine, 3-phenyl -1,1-dimethylurea and the like.

  In particular, compared to polymers such as phenol novolac resins, it is liquid at room temperature or has excellent solubility in organic solvents as described above and can be made to have a low viscosity, facilitating curing at a lower temperature and in a shorter time. It is preferable to use a low molecular weight curing agent and a curing accelerator with less coloring of the cured product.

  The thermosetting resin may be insoluble in alkali from the viewpoint of easily obtaining a color filter pixel portion having excellent reliability. The thermosetting resin is alkali-insoluble means that the amount of the thermosetting resin dissolved in a 1% by mass potassium hydroxide aqueous solution at 25 ° C. is 30% by mass or less based on the total mass of the thermosetting resin. Means that. The dissolution amount of the thermosetting resin is preferably 10% by mass or less, and more preferably 3% by mass or less.

  The weight-average molecular weight of the thermosetting resin is such that an appropriate viscosity is easily obtained as an ink-jet ink, the ink composition has good curability, and the solvent resistance of the pixel portion (cured product of the ink composition). From the viewpoint of improving the wear resistance, it may be 750 or more, 1000 or more, or 2000 or more. From the viewpoint of obtaining an appropriate viscosity as an inkjet ink, it may be 500000 or less, 300000 or less, or 200000 or less. However, the molecular weight after crosslinking is not limited to this.

  The content of the thermosetting resin is the viewpoint that an appropriate viscosity is easily obtained as an inkjet ink, the viewpoint that the curability of the ink composition is good, and the solvent resistance of the pixel portion (cured product of the ink composition). From the viewpoint of improving the wear resistance, it may be 10% by mass or more, 15% by mass or more, or 20% by mass or more, based on the mass of the nonvolatile content of the ink composition. From the viewpoint that the viscosity of the inkjet ink is not too high and the thickness of the pixel portion is not too thick for the light conversion function, the content of the thermosetting resin is based on the mass of the non-volatile content of the ink composition. It may be 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, or 50% by mass or less.

  In this embodiment, the ink composition only needs to contain at least one of a photopolymerizable compound and a thermosetting resin, and may contain both a photopolymerizable compound and a thermosetting resin. . When the ink composition contains a photopolymerizable compound, the ink composition may not contain a thermosetting resin. Moreover, the ink composition does not need to contain a photopolymerizable compound, when containing a thermosetting resin. From the viewpoint of storage stability of an ink composition containing luminescent nanocrystal particles (for example, quantum dots) and durability (wet heat stability, etc.) of a pixel portion (cured product of the ink composition), a photopolymerizable compound In addition, it is preferable to use a thermosetting resin among the thermosetting resins, the storage stability of the ink composition containing the luminescent nanocrystal particles (for example, quantum dots), and the low temperature that is not easily deteriorated by heating of the quantum dots. It is more preferable to use a photo-radically polymerizable compound from the viewpoint of being able to be cured at a photo-cation, and from the viewpoint that a pixel portion (cured product of the ink composition) can be formed without being subjected to oxygen inhibition in the curing process. It is preferable to use a functional compound.

  When the ink composition contains a photopolymerizable compound and a thermosetting resin, the total content of the photopolymerizable compound and the thermosetting resin is determined from the viewpoint that an appropriate viscosity is easily obtained as an inkjet ink. From the viewpoint of improving the properties, and improving the solvent resistance and abrasion resistance of the pixel portion (cured product of the ink composition), it is 3% by mass or more based on the mass of the nonvolatile content of the ink composition. It may be 5 mass% or more, 10 mass% or more, 15 mass% or more, or 20 mass% or more. In addition, the total content of the photopolymerizable compound and the thermosetting resin is an ink composition from the viewpoint that the viscosity of the inkjet ink does not become too high and the thickness of the pixel portion does not become too thick for the light conversion function. On the basis of the mass of the non-volatile matter, it may be 80% by mass or less, 60% by mass or less, or 50% by mass or less.

  The ink composition of the present embodiment can be applied as an ink used in a known and commonly used color filter manufacturing method, but does not waste materials such as luminescent nanocrystal particles and organic solvents that are relatively expensive. In addition, the color filter pixel part (light conversion layer) can be formed simply by using the required amount at the required location, so that it is appropriately prepared and used so as to be more suitable for the inkjet method than for the photolithography method. Is preferred.

  The viscosity of the ink composition is, for example, 2 mPa · s or more, 5 mPa · s or more, or 7 mPa · s or more from the viewpoint of ejection stability during ink jet printing. The viscosity of the ink composition may be 20 mPa · s or less, 15 mPa · s or less, or 12 mPa · s or less. When the viscosity of the ink composition is 2 mPa · s or more, the meniscus shape of the ink composition at the tip of the ink discharge hole of the discharge head is stabilized, so that the discharge control of the ink composition (for example, the discharge amount and the discharge timing) Control). On the other hand, when the viscosity is 20 mPa · s or less, the ink composition can be smoothly discharged from the ink discharge hole. The viscosity of the ink composition is 2 to 20 mPa · s, 2 to 15 mPa · s, 2 to 12 mPa · s, 5 to 20 mPa · s, 5 to 15 mPa · 2 to 20 mPa · s, 7 to 15 mPa · s, 7 to 12 mPa · s. -S, s, or 7-12 mPa * s may be sufficient. The viscosity of the ink composition is measured by, for example, an E-type viscometer.

  The surface tension of the ink composition is preferably a surface tension suitable for an ink jet system, specifically, a range of 20 to 40 mN / m is preferable, and a range of 25 to 35 mN / m is more preferable. . By making the surface tension within this range, the occurrence of flight bending can be suppressed. Note that the flight bend means that when the ink composition is ejected from the ink ejection hole, the landing position of the ink composition deviates by 30 μm or more from the target position. When the surface tension is 40 mN / m or less, the meniscus shape at the tip of the ink discharge hole is stable, and thus the discharge control of the ink composition (for example, control of the discharge amount and discharge timing) becomes easy. On the other hand, when the surface tension is 20 mN / m or less, the occurrence of flight bending can be suppressed. That is, a pixel portion that is not accurately landed on the pixel portion formation region to be landed and is insufficiently filled with the ink composition, or a pixel portion formation region (or pixel portion) adjacent to the pixel portion formation region to be landed Thus, the ink composition does not land and the color reproducibility does not deteriorate.

  The ink composition is not limited to the effect of the present invention, but other than luminescent nanocrystal particles, light scattering particles, photopolymerizable compounds, thermosetting resins, polymer dispersants, polymerization initiators and organic ligands. These components may be further contained. Examples of other components include a sensitizer and a solvent.

[Sensitizer]
As the sensitizer, amines that do not cause an addition reaction with the photopolymerizable compound and the thermosetting resin can be used. Examples of the sensitizer include trimethylamine, methyldimethanolamine, triethanolamine, p-diethylaminoacetophenone, ethyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, N, N-dimethylbenzylamine, 4, 4′-bis (diethylamino) benzophenone and the like can be mentioned.

[Organic solvent]
Examples of the organic solvent 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. Examples include diethyl, 1,4-butane, all diacetate, and glyceryl triacetate.

  The boiling point of the organic solvent is preferably 180 ° C. or higher from the viewpoint of continuous ejection stability of the inkjet ink. Further, when forming the pixel portion, it is necessary to remove the organic solvent from the ink composition before the ink composition is cured. Therefore, the boiling point of the solvent is preferably 300 ° C. or less from the viewpoint of easy removal of the organic solvent. .

  When a thermosetting resin is not used and a photopolymerizable compound is not used, a color filter pixel portion (light that has less unevenness by improving the fluidity of the ink composition and the viewpoint of preparing the ink composition to be uniform) From the viewpoint of forming the conversion layer), it is preferable to use an organic solvent. On the other hand, when a photopolymerizable compound is used, it is possible to disperse the light-scattering particles and the light-emitting nanocrystal particles in the photopolymerizable compound without a solvent. In this case, there is an advantage that a step of removing the organic solvent by drying is not necessary when forming the pixel portion.

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

  When the ink composition is used in a photographic system, first, the ink composition is applied onto a substrate, and when the ink composition contains an organic solvent, the ink composition is further dried to form a coating film. . The coating film thus obtained is soluble in an alkali developer and is patterned by being treated with the alkali developer. At this time, since the alkali developer is mostly an aqueous solution from the viewpoint of easiness of waste liquid treatment of the developer, the coating film of the ink composition is treated with the aqueous solution. On the other hand, in the case of an ink composition using luminescent nanocrystal particles (quantum dots or the like), the luminescent nanocrystal particles are unstable with respect to water, and the luminescent property (for example, fluorescence) is impaired by moisture. For this reason, in the present embodiment, an inkjet method that does not require treatment with an alkaline developer (aqueous solution) is preferable.

Even when the coating film of the ink composition is not treated with an alkali developer, when the ink composition is alkali-soluble, the coating film of the ink composition easily absorbs moisture in the atmosphere, and the time As the time elapses, the light-emitting property (for example, fluorescence) of the light-emitting nanocrystal particles (quantum dots or the like) is impaired. From this point of view, in the present embodiment, the coating film of the ink composition is preferably insoluble in alkali. 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 / or an alkali-insoluble thermosetting resin as the photopolymerizable compound and / or thermosetting resin. The coating film of the ink composition is insoluble in alkali. The amount of dissolution of the coating film of the ink composition at 25 ° C. in a 1% by mass potassium hydroxide aqueous solution is based on the total mass of the coating film of the ink composition. It means 30% by mass or less. The dissolution amount of the coating film of the ink composition is preferably 10% by mass or less, more preferably 3% by mass or less. It should be noted that the ink composition is an ink composition capable of forming an alkali-insoluble coating film when it is applied to a substrate and then dried at 80 ° C. for 3 minutes when it contains a solvent. It can confirm by measuring the said dissolution amount of the coating film of thickness 1 micrometer obtained.

<Method for producing ink composition>
Next, a method for producing the ink composition of the above-described embodiment will be described. The method for producing an ink composition includes, for example, a first step of preparing a dispersion of light scattering particles containing light scattering particles and a polymer dispersant, a dispersion of light scattering particles, and a light-emitting nanoparticle. A second step of mixing the crystal particles. In this method, the dispersion of light scattering particles may further contain a photopolymerizable compound and / or a thermosetting resin, and in the second step, the photopolymerizable compound and / or the thermosetting resin. The resin may be further mixed. According to this method, the light scattering particles can be sufficiently dispersed. Therefore, it is possible to easily obtain an ink composition that can improve light conversion efficiency with reduced leakage light in the pixel portion.

  In the step of preparing a dispersion of light-scattering particles, the light-scattering particles, the polymer dispersant, and optionally a photopolymerizable compound and / or a thermosetting resin are mixed and subjected to a dispersion treatment. Thus, a dispersion of light scattering particles may be prepared. The mixing and dispersing treatment may be performed using a dispersing device such as a bead mill, a paint conditioner, a planetary stirrer or the like. It is preferable to use a bead mill or a paint conditioner from the viewpoint of good dispersibility of the light scattering particles and easy adjustment of the average particle diameter of the light scattering particles to a desired range.

  The method for producing an ink composition includes a dispersion of luminescent nanocrystal particles containing luminescent nanocrystal particles, a photopolymerizable compound, and / or a thermosetting resin before the second step. You may further provide the process to prepare. In this case, in the second step, the dispersion of light scattering particles and the dispersion of luminescent nanocrystal particles are mixed. According to this method, the luminescent nanocrystal particles can be sufficiently dispersed. Therefore, an ink composition that can reduce leakage light in the pixel portion can be easily obtained. In the step of preparing a dispersion of luminescent nanocrystal particles, the same dispersing device as the step of preparing a dispersion of light-scattering particles is used, and the luminescent nanocrystal particles, the photopolymerizable compound, and / or Mixing and dispersion treatment with a thermosetting resin may be performed.

  When the ink composition of this embodiment is used as an ink composition for an ink jet system, it is preferably applied to a piezo jet ink jet recording apparatus using 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, the luminescent nanocrystal particles are not easily altered, and the light emission characteristics as expected by the color filter pixel part (light conversion layer) Is easier to obtain.

  Since the ink composition of the present invention contains a singlet oxygen quencher, it is an ink composition having improved stability in the atmosphere, and particularly excellent stability when exposed to light in the atmosphere. However, if necessary, moisture and / or gases other than singlet oxygen and other gases including inert gas (deaeration) are removed to remove moisture and gas from the ink composition. Thus, it is possible to obtain an ink composition that is more stable with respect to continuous ejection in the ink jet system, in which the deterioration of the light-emitting nanocrystal is less. Singlet oxygen quencher addition, moisture removal and gas removal (degassing) require the addition of a singlet oxygen quencher and can be performed in any order, including the latter two means. However, the most excellent effect is obtained by adding a singlet oxygen quencher after moisture or deaeration from the ink raw material or ink composition.

<Light conversion layer and color filter>
Next, details of the light conversion layer and the color filter using the ink composition of the above-described embodiment 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 duplicate descriptions are omitted.

  FIG. 1 is a schematic cross-sectional view of a color filter according to an 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 units 10 and a light shielding unit 20.

The light conversion layer 30 includes, as the pixel unit 10, a first pixel unit 10a, a second pixel unit 10b, and a third pixel unit 10c. The first pixel unit 10a, the second pixel unit 10b, and the third pixel unit 10c are arranged in a lattice pattern so as to be repeated in this order. The light shielding unit 20 is provided between adjacent pixel units, that is, between the first pixel unit 10a and the second pixel unit 10b, between the second pixel unit 10b and the third pixel unit 10c, and third. The pixel portion 10c and the first pixel portion 10a are provided. In other words, these adjacent pixel portions are separated from each other by the light shielding portion 20.

  The first pixel portion 10a and the second pixel portion 10b each include a cured product of the ink composition of the above-described embodiment. The cured product contains luminescent nanocrystal particles, light scattering particles, and a curing component. The curing component is a cured product of a photopolymerizable compound and / or a thermosetting resin, and specifically, a cured product obtained by polymerization of the photopolymerizable compound and / or crosslinking of the thermosetting resin. That is, the first pixel unit 10a includes the first cured component 13a and the first light-emitting nanocrystal particles 11a and the first light-scattering particles 12a dispersed in the first cured component 13a. Including. Similarly, the second pixel portion 10b includes a second cured component 13b, second luminescent nanocrystal particles 11b and second light-scattering particles 12b dispersed in the second cured component 13b, respectively. including. In the first pixel portion 10a and the second pixel portion 10b, the first cured component 13a and the second cured component 13b may be the same or different, and the first light scattering particles 12a The second light scattering particles 12b may be the same or different.

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

  The content of the luminescent nanocrystal particles in the pixel portion including the cured product of the ink composition is 5% by mass or more based on the total mass of the cured product of the ink composition from the viewpoint of being excellent in the effect of reducing leakage light. It may be 10% by mass or more, 15% by mass or more, 20% by mass or more, 30% by mass or more, and 40% by mass or more. Also good. From the viewpoint of excellent reliability of the pixel portion, the content of the luminescent nanocrystal particles may be 70% by mass or less based on the total mass of the cured product of the ink composition, and may be 60% by mass or less. It may be 55% by mass or less, or 50% by mass or less.

The content of the light-scattering particles in the pixel portion including the cured product of the ink composition is 0.1% by mass or more based on the total mass of the cured product of the ink composition from the viewpoint of being excellent in the effect of reducing leakage light. 1 mass% or more, 5 mass% or more, 7 mass% or more, 10 mass% or more, or 12 mass% or more. May be. The content of the light-scattering particles may be 60% by mass or less based on the total mass of the cured product of the ink composition from the viewpoint of excellent leakage light reduction effect and excellent reliability of the pixel portion. 50% by mass or less, 40% by mass or less, 30% by mass or less, 25% by mass or less, or 20% by mass or less, It may be 15% by mass or less. The content of the light scattering particles is 0.1 to 60% by mass, 0.1 to 50% by mass, 0.1 to 40% by mass, 0.1 to 0.1% by mass based on the total mass of the cured product of the ink composition. 30% by mass, 0.1-25% by mass, 0.1-20% by mass, 0.1-15% by mass, 1-60% by mass, 1-50% by mass, 1-40% by mass, 1-30% by mass %, 1-25% by mass, 1-20% by mass, 1-15% by mass, 5-60% by mass, 5-50% by mass, 5-40% by mass, 5-30% by mass, 5-25% by mass, 5-20 mass%, 5-15 mass%, 7-60 mass%, 7-50 mass%, 7-40 mass%, 7-30 mass%, 7-25 mass%, 7-20 mass%, 7- 15 mass%, 10-60 mass%, 10-50 mass%, 10-40 mass%, 10-30 mass%, 10-25 mass%, 10-20 mass%, 10-15 mass% 12-60 wt%, 12-50 wt%, 12-40 wt%, 12 to 30 wt%, 12 to 25 wt%, may be 12-20%, or 12-15 wt%.

  The third pixel portion 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 unit 10c functions as a blue pixel unit when a light source that emits light having a wavelength in the range of 420 to 480 nm is used. The 3rd pixel part 10c contains the hardened | cured material of the composition containing the above-mentioned photopolymerizable compound and / or a thermosetting resin, for example. The cured product contains a third curing component 13c. The third curing component 13c is a cured product of a photopolymerizable compound and / or a thermosetting resin, and specifically, a cured product obtained by polymerization of the photopolymerizable compound and / or crosslinking of the thermosetting resin. It is. That is, the third pixel portion 10c includes the third curing component 13c. When the 3rd pixel part 10c contains the above-mentioned hardened | cured material, the transmittance | permeability with respect to the light of the wavelength of the range of 420-480 nm is 30% for the composition containing a photopolymerizable compound and / or a thermosetting resin. As long as it becomes the above, you may further contain components other than a photopolymerizable compound and a thermosetting resin among the components contained in the above-mentioned ink composition. Note that the transmittance of the third pixel portion 10c can be measured by a microspectroscopic device.

  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 be. 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 be.

  The light shielding unit 20 is a so-called black matrix provided for the purpose of preventing color mixture by separating adjacent pixel units and preventing light leakage from the light source. The material constituting the light-shielding part 20 is not particularly limited, and curing of a resin composition containing light-shielding particles such as carbon fine particles, metal oxides, inorganic pigments, organic pigments in a binder polymer in addition to a metal such as chromium. A thing etc. can be used. As the binder polymer used here, polyimide resin, acrylic resin, epoxy resin, polyacrylamide, polyvinyl alcohol, gelatin, casein, cellulose, or a mixture of two or more resins, photosensitive resin, O / W An emulsion type resin composition (for example, an emulsion of reactive silicone) can be used. The thickness of the light shielding part 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. For example, the base material 40 is a transparent glass substrate such as quartz glass, Pyrex (registered trademark) glass, or a synthetic quartz plate, a transparent resin film, an optical resin film, or the like. A flexible base material etc. can be used. Among these, it is preferable to use the glass substrate which consists of an alkali free glass which does not contain an alkali component in glass. Specifically, “7059 glass”, “1737 glass”, “Eagle 200” and “Eagle XG” manufactured by Corning, “AN100” manufactured by Asahi Glass, “OA-10G” manufactured by Nippon Electric Glass, and “ OA-11 "is preferred. These are materials having 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 above light conversion layer 30 is preferably used when a light source that emits light having a wavelength in the range of 420 to 480 nm is used.

  For example, the color filter 100 is formed by forming the light-shielding portion 20 on the base material 40 in a pattern, and then forming the ink composition (in the above-described embodiment) on the pixel portion forming region partitioned by the light-shielding portion 20 on the base material 40. Ink-jet ink) can be selectively deposited by an ink-jet method and can be produced by a method of curing the ink composition by irradiation with active energy rays or heating.

  The light shielding part 20 is formed by forming a metal thin film such as chromium or a resin composition thin film containing light shielding particles in a region serving as a boundary between a plurality of pixel parts on one side of the substrate 40. And a method of patterning the thin film. The metal thin film can be formed by, for example, a sputtering method, a vacuum deposition method, or the like, and the thin film of the resin composition containing the light-shielding particles can be formed by, for example, a method such as coating or printing. Examples of the patterning method include a photolithography method.

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

When the ink composition is cured by irradiation with active energy rays (for example, ultraviolet rays), 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 amount may be, for example, 10 mJ / cm ² or more and may be 4000 mJ / cm ² or less.

  When the ink composition is cured by heating, the heating temperature may be, for example, 110 ° C. or higher and 250 ° C. or lower. The heating time may be, for example, 10 minutes or more and 120 minutes or less.

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

  For example, the light conversion layer may be a pixel portion including a cured product of an ink composition containing blue light-emitting nanocrystal particles instead of or in addition to the third pixel portion 10c. A blue pixel portion). The light conversion layer may include a pixel portion (for example, a yellow pixel portion) including a cured product of an ink composition containing nanocrystal particles that emit light of a color other than red, green, and blue. In these cases, each of the luminescent nanocrystal particles contained in each pixel portion of the light conversion layer preferably has an absorption maximum wavelength in the same wavelength region.

  In addition, at least a part of the pixel portion of the light conversion layer may include a cured product of a composition containing a pigment other than the light-emitting nanocrystal particles.

  The color filter may include an ink repellent layer made of a material having an ink repellency narrower than that of the light shielding portion on the pattern of the light shielding portion. Also, instead of providing an ink repellent layer, a photocatalyst-containing layer as a wettability variable layer is formed in a solid shape in a region including the pixel portion formation region, and then light is passed through the photocatalyst-containing layer through a photomask. Exposure may be performed by irradiation to selectively increase the ink affinity of the pixel portion formation region. Examples of the photocatalyst include titanium oxide.

  The color filter may include an ink receiving layer containing hydroxypropyl cellulose or the like between the base material and the pixel portion.

  The color filter may include a protective layer on the pixel portion. This protective layer flattens the color filter and prevents elution of components contained in the pixel portion, or components contained in the pixel portion and components contained in the photocatalyst containing layer into the liquid crystal layer. It is provided. As the material constituting the protective layer, those used as known color filter protective layers can be used.

  In manufacturing the color filter and the light conversion layer, the pixel portion may be formed by a photolithography method instead of the ink jet method. In this case, first, the ink composition is applied to the base material in layers to form an ink composition layer. Next, the ink composition layer is exposed in a pattern and then developed using a developer. In this way, a pixel portion made of a cured product of the ink composition is formed. Since the developer is usually alkaline, an alkali-soluble polymer is used as the binder polymer. However, the ink jet method is superior to the photolithography method in terms of material use efficiency. This is because, in the photolithography method, approximately 2/3 or more of the material is removed in principle, and the material is wasted. For this reason, in this embodiment, it is preferable to form a pixel part by an inkjet system using inkjet ink.

  In addition to the above-described luminescent nanocrystal particles, 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 nanocrystal particles. For example, when a pixel portion containing luminescent nanocrystal particles that absorb blue light and emit light is used as the pixel portion of the liquid crystal display element, blue light or quasi-white light having a peak at 450 nm as light from the light source However, when the concentration of the light-emitting nanocrystal particles in the pixel portion is not sufficient, light from the light source passes through the light conversion layer when the liquid crystal display element is driven. The transmitted light (blue light, leakage light) from this light source and the light emitted from the light-emitting nanocrystal particles are mixed. From the viewpoint of preventing the color reproducibility from being deteriorated due to the occurrence of such color mixing, a pigment may be contained in the pixel portion of the light conversion layer. In order to contain the pigment in the pixel portion, the ink composition may contain a 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 not included in the light emitting nanocrystal particles. A pixel portion containing a coloring material may be used. As the color material that can be used here, a known color material can be used. For example, as the color material used for the red pixel portion (R), a diketopyrrolopyrrole pigment and / or an anionic red organic dye can be used. Can be mentioned. Examples of the color material used for the green pixel portion (G) include at least one selected from the group consisting of a halogenated copper phthalocyanine pigment, a phthalocyanine green dye, and a mixture of a phthalocyanine blue dye and an azo yellow organic dye. Examples of the color material used for the blue pixel portion (B) include an ε-type copper phthalocyanine pigment and / or a cationic blue organic dye. When used in the light conversion layer, these coloring materials are used in an amount of 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. % Is preferred.

  Hereinafter, the present invention will be described specifically by way of examples. However, the present invention is not limited only to the following examples.

  The operation for producing the following luminescent nanocrystals and the operation for producing the ink were carried out in a glove box filled with nitrogen or in a flask under a nitrogen stream.

  In addition, all the raw materials exemplified below were used by previously replacing the atmosphere in the container with nitrogen gas by introducing nitrogen gas into the container.

  In addition, chloroform, ethanol, hexane, and toluene used below were dehydrated and dried for 48 hours or more in advance using molecular sieves (basically 3A was used, and hexane and toluene was 4A).

[Production of red light-emitting nanocrystals]
A 1000 ml flask was charged with 17.48 g of indium acetate, 25.0 g of trioctylphosphine oxide, and 35.98 g of lauric acid, and stirred at 160 ° C. for 40 minutes while bubbling with nitrogen gas. The mixture was further stirred at 250 ° C. for 20 minutes and then heated to 300 ° C. to continue stirring. In a glove box, 4.0 g of tris (trimethylsilyl) phosphine was dissolved in 15.0 g of trioctylphosphine and then filled into a glass syringe. This was poured into a flask kept at 300 ° C. and reacted at 250 ° C. for 10 minutes. Further, 5 ml of a mixed solution in which 7.5 g of tris (trimethylsilyl) phosphine was dissolved in 30.0 g of trioctylphosphine was dropped into the reaction solution in 12 minutes in the glove box, and then 5 ml of the reaction solution at 15-minute intervals until it was used up. Added to.

  In another three-necked flask, 5.595 g of indium acetate, 10.0 g of trioctylphosphine oxide, and 11.515 g of lauric acid were charged and stirred at 160 ° C. for 40 minutes while bubbling with nitrogen gas. The mixture was further stirred at 250 ° C. for 20 minutes and heated to 300 ° C., and then the mixed solution cooled to 70 ° C. was added to the reaction solution. In a glove box, 5 ml of a mixed solution in which 4.0 g of tris (trimethylsilyl) phosphine was dissolved in 15.0 g of trioctylphosphine was dropped again into the above reaction solution over 12 minutes, and then 5 ml was reacted at 15 minute intervals until used up. Added to the solution. After stirring for 1 hour and cooling to room temperature, 100 ml of toluene and 400 ml of ethanol were added to aggregate the fine particles. After precipitating fine particles using a centrifuge, the supernatant was discarded, and the precipitated fine particles were dissolved in trioctylphosphine to obtain a trioctylphosphine solution of indium phosphide (InP) red light emitting nanocrystals. .

[Production of green light-emitting nanocrystals]
A 1000 ml flask was charged with 23.3 g of indium acetate, 40.0 g of trioctylphosphine oxide, and 48.0 g of lauric acid, and stirred at 160 ° C. for 40 minutes while bubbling with nitrogen gas. The mixture was further stirred at 250 ° C. for 20 minutes and then heated to 300 ° C. to continue stirring. In a glove box, 10.0 g of tris (trimethylsilyl) phosphine was dissolved in 30.0 g of trioctylphosphine and then filled into a glass syringe. This was poured into a flask kept at 300 ° C. and reacted at 250 ° C. for 5 minutes. The flask was cooled to room temperature, and 100 ml of toluene and 400 ml of ethanol were added to aggregate the fine particles. After the microparticles were precipitated using a centrifuge, the supernatant was discarded, and the precipitated microparticles were dissolved in trioctylphosphine to obtain a trioctylphosphine solution of indium phosphide (InP) green light-emitting nanocrystals. .

[Production of InP / ZnS core-shell nanocrystals]
After adjusting the InP nanocrystal trioctylphosphine solution synthesized above to 3.6 g of InP and 90 g of trioctylphosphine, the mixture is put into a 1000 ml flask, and 90 g of trioctylphosphine oxide and 30 g of lauric acid are added. On the other hand, a stock solution is prepared by mixing 162 g of trioctylphosphine with 42.9 ml of 1M hexane solution of diethylzinc and 92.49 g of a 9.09 wt% solution of bistrimethylsilyl sulfide in a glove box. After the inside of the flask was replaced with a nitrogen atmosphere, the temperature of the flask was set at 180 ° C., and when the temperature reached 80 ° C., 15 ml of the stock solution was added, and then 15 ml was continuously added every 10 minutes. (Flask temperature is maintained at 180 ° C.). After the last addition, the reaction was terminated by maintaining the temperature for another 10 minutes. After completion of the reaction, the solution was cooled to room temperature, and 500 ml of toluene and 2000 ml of ethanol were added to aggregate the nanocrystals. After the nanocrystals are precipitated using a centrifuge, the supernatant is discarded, and the precipitate is dissolved again in chloroform so that the nanocrystal concentration in the solution is 20% by mass, whereby the InP / ZnS core-shell nanocrystals are dissolved. A chloroform solution was obtained.

[QD ligand exchange]
With reference to JP-A No. 2002-121549 (published patent publication of Mitsubishi Chemical Corporation), triethylene glycol monomethyl ether ester (triethylene glycol monomethyl ether mercaptopropionate) (TEGMEMP) of 3-mercaptopropanoic acid was synthesized.

  In a container filled with nitrogen gas, QD dispersion 1 (the above InP / ZnS core-shell nanocrystal (red light emitting)) and 80 g of a chloroform solution in which 8 g of TEGMEMP synthesized above were dissolved were mixed at 80 ° C. for 2 hours. Ligand exchange was performed by stirring, and it cooled to room temperature.

  Thereafter, toluene / chloroform was evaporated while stirring at 40 ° C. under reduced pressure, and the solution was concentrated until the liquid volume became 100 ml. Four times the weight of n-hexane was added to this dispersion to aggregate QD, and the supernatant was removed by centrifugation and decantation. 50 g of toluene was added to the precipitate and redispersed with ultrasound. This washing operation was performed three times in total to remove the free ligand component remaining in the solution. The precipitate after decantation was vacuum-dried at room temperature for 2 hours to obtain 2 g of QD (QD-TEGMEMP) powder modified with TEGMEMMP.

[Preparation of QD / alicyclic epoxy monomer dispersion 1]
QD / alicyclic epoxy monomer dispersion 1 (QD content: 20) was prepared by mixing 2 g of the above QD-TEGMEMP and 8 g of the alicyclic epoxy monomer in a container filled with nitrogen gas, and then dispersing with ultrasonic waves. Mass%).

[Preparation of titanium oxide dispersion]
In a container filled with nitrogen gas, 12.9 g of titanium oxide, 1.3 g of a polymer dispersant, and 18.1 g of oxetane monomer were blended. After adding zirconia beads (diameter: 1.25 mm) to the compound in the container filled with nitrogen gas, the compound container is dispersed by shaking the sealed container filled with nitrogen gas for 2 hours using a paint conditioner. Went. Next, nitrogen gas was introduced to replace dissolved oxygen with nitrogen gas, and a light scattering particle dispersion 1 was obtained.

[Example 1]
[Preparation of ink composition]
In a container filled with nitrogen gas, 6.47 g of QD / alicyclic epoxy monomer dispersion 1, 3.23 g of light scattering particle dispersion 1, 0.3 g of photocationic polymerization initiator, After 0.35 g of the singlet oxygen quencher shown in Table 1 is mixed and dissolved, the mixture is filtered through a filter having a pore size of 5 μm in the glove box, and nitrogen gas is introduced into the ink to saturate the nitrogen gas. It was.

  Subsequently, the ink composition was obtained by removing nitrogen gas under reduced pressure. The materials used are as follows.

[Light scattering particles]
-Titanium oxide: JR-806 (trade name, average particle diameter (volume average diameter) manufactured by Teika Co., Ltd.)
: 300nm)
[Photopolymerizable compound]
-Alicyclic epoxy monomer: LDO (trade name of Sakai Industry Co., Ltd.)
Oxetane monomer: Aron oxetane OXT-221 (trade name, manufactured by Toa Gosei Co., Ltd.)
"Aron Oxetane" is a registered trademark)
[Polymer dispersant]
Polymer dispersing agent: DISPERBYK-2155 (trade name manufactured by BYK,
"DISPERBYK" is a registered trademark)
[Polymerization initiator]
Photocationic polymerization initiator: CPI-100P (trade name, “CPI” manufactured by Sun Apro Co., Ltd.)
Is a registered trademark)

  The above materials were dehydrated for 48 hours or more in advance with Molecular Sieves 3A before mixing.

  Titanium oxide was heated at 120 ° C. for 2 hours under a reduced pressure of 1 mmHg before mixing and allowed to cool in a nitrogen gas atmosphere.

[Example 2]
[Preparation of ink composition]
An ink composition was obtained in the same manner as in Example 1 except that the QD / alicyclic epoxy monomer dispersion 2 was used in a container filled with nitrogen gas.

[Comparative Example 1]
An ink composition was obtained in the same manner as in Example 1 except that the singlet oxygen quencher was not used.

[Comparative Example 2]
An ink composition was obtained in the same manner as in Example 2 except that the singlet oxygen quencher was not used.

(2) Preparation of light conversion filter The ink composition obtained above was applied onto a glass substrate with a spin coater so that the film thickness after drying was 2.4 μm. The obtained film was irradiated with ultraviolet rays of 12 mW / cm ² . Thus, the ink composition was cured to form a layer (light conversion layer) made of a cured product of the ink composition on the glass substrate. The light conversion filter was obtained by the above operation.

(3) Evaluation Using the ink composition obtained above and the light conversion filter obtained above, light conversion efficiency was evaluated according to the following procedure. The results are shown in Table 1.

[External quantum efficiency (EQE)]
A blue LED (peak emission wavelength: 450 nm) manufactured by CCS Co., Ltd. was used as a surface emitting light source. The measuring device was an integrating sphere connected to a radiation spectrophotometer (trade name “MCPD-9800”) manufactured by Otsuka Electronics Co., Ltd., and the integrating sphere was installed above the blue LED. A base material having a light conversion layer was inserted between the blue LED and the integrating sphere, and the spectrum observed by turning on the blue LED and the illuminance at each wavelength were measured.

  The external quantum efficiency was determined from the spectrum measured by the above measuring apparatus and the illuminance as follows. This value is a value indicating how much of the light (photons) incident on the light conversion layer is emitted as fluorescence to the observer side. Therefore, a large value indicates that the light conversion layer is excellent, and is an important evaluation index.

External quantum efficiency of red light-emitting light conversion layer = P (Red) / E (Blue) × 100 (%)
External quantum efficiency of green light emitting conversion layer = P (Green) / E (Blue) × 100 (%)

Here, E (Blue), P (Red), and P (Green) each represent the following.
E (Blue):
The total value w in this wavelength range of “illuminance × wavelength ÷ hc” at a wavelength of 380 to 490 nm (or 380 to 500 nm) is represented. Here, h is the Planck constant and c is the speed of light. (This is a value corresponding to the number of observed photons.)
P (Red):
The total value in this wavelength range of “illuminance × wavelength ÷ hc” at a measurement wavelength of 490 to 590 nm is represented. (Corresponds to the number of observed photons)
P (Green):
The total value in this wavelength range of “illuminance × wavelength ÷ hc” at a measurement wavelength of 590 to 780 nm is represented. (Corresponds to the number of observed photons)

The EQE was calculated, and the EQEs of Comparative Example 1 that emits red light and Comparative Example 2 that emits green light each without addition of a singlet oxygen quencher were set to 10, and the measured EQE of each sample was expressed as a relative value as follows: evaluated.
<Evaluation criteria>
10: C
More than 10 and less than 100: B
More than 100: A

Example 3
First, a substrate (BM substrate) having a light shielding portion called a black matrix (BM) was manufactured by the following procedure. That is, after applying a black resist (“CFPR BK” manufactured by Tokyo Ohka Kogyo Co., Ltd.) on a glass substrate made of alkali-free glass (“OA-10G” manufactured by Nippon Electric Glass Co., Ltd.), pre-baking, pattern exposure, development and By performing post-baking, a patterned light-shielding portion was formed. The exposure was performed by irradiating the black resist with ultraviolet rays at an exposure amount of 250 mJ / cm ² . The pattern of the light shielding portion is a pattern having an opening corresponding to a sub pixel of 200 μm × 600 μm, the line width is 20 μm, and the thickness is 2.6 μm.

  Next, the red light-emitting ink composition obtained in Example 1 was printed on the opening on the BM substrate by an ink jet method, irradiated with ultraviolet rays, and then heated at 150 ° C. for 30 minutes in a nitrogen atmosphere. As a result, the ink composition was cured to form a pixel portion made of a cured product of the ink composition. The obtained pixel portion is a pixel portion that converts blue light into red light. The thickness of the pixel portion was 2.1 μm. The light conversion filter with a pattern was obtained by the above operation.

Example 4
A BM substrate was prepared in the same manner as in Example 3. Next, the red light-emitting ink composition obtained in Example 1 and the green light-emitting ink composition obtained in Example 2 were printed on the opening on the BM substrate by an inkjet method, and then irradiated with ultraviolet rays. The ink composition was cured in the same manner as described above. Thereby, the pixel part which converts blue light into red light and the pixel part which converts blue light into green light were formed on the BM substrate. With the above operation, a patterned light conversion filter including a plurality of types of pixel portions was obtained.

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, 20 ... light-shielding part, 30 ... light conversion layer, 40 ... base material, 100 ... color filter.

Claims (21)

  An ink composition comprising luminescent nanocrystal particles, a curing component, and a singlet oxygen quencher. 2. The ink composition according to claim 1, wherein the singlet oxygen quencher is a compound having a quenching rate constant of singlet oxygen of k = 10 ⁷ M ⁻¹ s ⁻¹ or more.   The singlet oxygen quencher is a nickel compound, a diimonium salt, 1,4-diazabicyclo [2.2.2. The ink composition according to claim 1 or 2, which is at least one compound selected from the group consisting of octane, aniline compounds, luminol, bilirubin, β-carotene, and furan compounds. The ink composition according to claim 1, wherein the curable component is a thermosetting resin. The ink composition according to claim 1, wherein the curing component is a photopolymerizable compound. The ink composition according to claim 5, wherein the photopolymerizable compound is a radical photopolymerizable compound. The ink composition according to claim 5, wherein the photopolymerizable compound is insoluble in alkali. The ink composition according to claim 4, wherein the thermosetting resin is alkali-insoluble.   The ink composition according to claim 7 or 8, wherein an ink-insoluble coating film can be formed. The ink composition according to any one of claims 1 to 3, wherein the dissolved oxygen concentration is 0 to 6 mg / L.   The ink composition according to any one of claims 1 to 3, wherein the ink composition is for inkjet printing.   The inkjet ink composition according to claim 11, wherein the surface tension is 20 to 40 mN / m.   The inkjet ink composition according to claim 11, having a viscosity of 2 to 20 mPa · s.   The inkjet ink composition according to claim 11, further comprising a solvent having a boiling point of 180 ° C. or higher.   The inkjet ink composition according to claim 11, which is used for a color filter.   A light conversion layer comprising a cured product of the ink composition according to claim 1.   A light conversion layer, wherein the light conversion layer comprising a cured product of the ink composition according to claim 9 is insoluble in alkali. A light conversion layer comprising a plurality of pixel portions,
The light conversion layer, wherein the plurality of pixel portions have pixel portions including a cured product of the ink-jet ink composition according to any one of claims 11 to 15. A light shielding part provided between the plurality of pixel parts;
The plurality of pixel portions are
The light-emitting nanocrystal particles containing the cured product and containing the light-emitting nanocrystal particles that absorb light having a wavelength in the range of 420 to 480 nm and emit light having an emission peak wavelength in the range of 605 to 665 nm are included. A first pixel portion;
The light-emitting nanocrystal particles containing the cured product and containing the light-emitting nanocrystal particles that absorb light having a wavelength in the range of 420 to 480 nm and emit light having a light emission peak wavelength in the range of 500 to 560 nm. The light conversion layer according to claim 11, further comprising: a second pixel portion. 20. The light conversion layer according to claim 19, wherein the plurality of pixel portions further include a third pixel portion having a transmittance of 30% or more for light having a wavelength in a range of 420 to 480 nm.   A color filter comprising the light conversion layer according to any one of claims 17 to 20.

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