CN112285999A

CN112285999A - Solvent-free curable composition, cured film, color filter, and display device

Info

Publication number: CN112285999A
Application number: CN202010703177.3A
Authority: CN
Inventors: 金东俊; 姜龙熙; 金美善; 金钟基; 朴民志; 李范珍; 林知泫; 崔美贞
Original assignee: Samsung SDI Co Ltd
Current assignee: Samsung SDI Co Ltd
Priority date: 2019-07-22
Filing date: 2020-07-21
Publication date: 2021-01-29
Also published as: KR102449846B1; TWI807200B; KR20210011227A; TW202104402A

Abstract

The present invention discloses a solvent-free type curable composition, a cured film manufactured using the same, a color filter including the cured film, and a display device including the color filter, the solvent-free type curable composition including: (A) quantum dots; (B) a polymerizable monomer; and (C) a light diffusing agent having a primary particle diameter of 50 nm to 200 nm and a secondary particle diameter of 120 nm to 250 nm. The solvent-free curable composition containing quantum dots can redisperse at a reduced density in a short time while maximizing the scattering effect of the quantum dots. Thus, high brightness and high color of a color filter including a cured film manufactured using the composition can be achieved.

Description

Solvent-free curable composition, cured film, color filter, and display device

This application claims priority and benefit from korean patent application No. 10-2019-0088405, filed by the korean intellectual property office at 7/22/2019, the entire contents of which are incorporated herein by reference.

Technical Field

The present disclosure relates to a solvent-free curable composition, a cured film manufactured using the same, a color filter including the cured film, and a display device including the color filter.

Background

In general, a color filter applied to a display is formed by the steps of: using the photosensitive resist composition, a desired pattern is formed through an exposure process by using a photomask and then the non-exposed region is dissolved and removed through a development process. The material of the color filter may require alkali solubility, high sensitivity, adhesion to a substrate, chemical resistance, heat resistance, and the like. For the coloring material, a pigment or a dye is generally used.

However, a pigment has excellent heat resistance or chemical resistance but is not well dispersed in a solvent, and thus does not have excellent color characteristics such as brightness, while a dye has excellent color characteristics but is deteriorated in durability, and thus does not have excellent heat resistance or chemical resistance.

Accordingly, a novel photoluminescence-type photosensitive resin composition and a color filter material to which such a novel photoluminescence-type photosensitive resin composition (i.e., a composition using quantum dots) is applied, which can overcome technical limitations of currently used photosensitive resin compositions using pigments or dyes as color materials, are continuously being developed.

Such compositions containing quantum dots can be classified into a negative photoresist type prepared by a photolithography method and an ink type prepared by an inkjet method according to a process method, and the ink type compositions containing quantum dots can be further classified into a solvent type composition containing a solvent and a solvent-free type composition containing no solvent at all.

However, since the solvent-based ink composition has not only problems of nozzle drying due to solvent volatilization during ink jetting and thus nozzle clogging, monolayer film shrinkage over time after ink jetting, etc., but also disadvantages of severe thickness deviation after curing and thus difficulty in being applicable to practical processes, recently, a solvent-free ink composition not containing any solvent has been preferred. In addition, since the technology of applying quantum dots themselves to solvent-based compositions has been currently evaluated to reach a certain limit, the development demand for solvent-free ink compositions continues to increase.

Disclosure of Invention

The embodiment provides a solvent-free curable composition required for precipitation when light absorption and light conversion are maximized by controlling the primary particle diameter and the secondary particle diameter of a light diffuser.

Another embodiment provides a cured film made using a solventless curable composition.

Another embodiment provides a color filter including the cured film.

Another embodiment provides a display device including a color filter.

Embodiments provide a solvent-free curable composition comprising (a) quantum dots; (B) a polymerizable monomer; and (C) a light diffusing agent having a primary particle diameter of 50 nm to 200 nm and a secondary particle diameter of 120 nm to 250 nm.

The light diffusing agent may have a primary particle diameter of 80 nm to 180 nm and a secondary particle diameter of 140 nm to 230 nm.

The secondary particle size of the light diffusing agent may have a size 1.5 times to 2.5 times the primary particle size of the light diffusing agent.

The light diffusing agent may be a mixture of a rutile type light diffusing agent and an anatase type light diffusing agent.

The rutile type light diffusing agent and the anatase type light diffusing agent in the mixture may be included in a weight ratio of 1:3 to 3: 1.

The light diffusing agent may comprise barium sulfate, calcium carbonate, titanium dioxide, zirconium oxide, or a combination thereof.

The quantum dots may comprise quantum dots having a maximum fluorescence emission wavelength (fluorescence λ) of 450 nm to 580 nm_em) Has a maximum fluorescence emission wavelength (fluorescence lambda) of 580 to 700 nm_em) Or a combination thereof.

The solventless curable composition may further comprise a polymerization initiator.

The solventless curable composition may further comprise a polymerization inhibitor; malonic acid; 3-amino-1, 2-propanediol; a silane-based coupling agent; a leveling agent; a fluorine-based surfactant; or a combination thereof.

Another embodiment provides a color filter including the cured film.

Another embodiment provides a display device including a color filter.

Other embodiments of the invention are included in the following detailed description.

The solvent-free curable composition containing quantum dots according to the embodiment includes a light diffuser having controlled primary particle diameters and secondary particle diameters, and thus it is possible to redisperse in a short time with a reduced density while maximizing the scattering effect of quantum dots. Thus, high brightness and high color of a color filter including a cured film manufactured using the composition can be achieved.

Drawings

Fig. 1 is a schematic view showing the primary particle diameter and the secondary particle diameter of a light diffusing agent.

Fig. 2 is a graph of X-ray analysis of the crystal phase of the light diffusing agent used in example 5.

Fig. 3 is a graph of X-ray analysis of the crystal phase of the light diffusing agent used in example 4.

Detailed Description

Hereinafter, embodiments of the present invention are described in detail. However, these embodiments are exemplary, the present invention is not limited thereto and the present invention is defined by the scope of the claims.

In the present specification, when a specific definition is not otherwise provided, "alkyl" means C1 to C20 alkyl, "alkenyl" means C2 to C20 alkenyl, "cycloalkenyl" means C3 to C20 cycloalkenyl, "heterocycloalkenyl" means C3 to C20 heterocycloalkenyl, "aryl" means C6 to C20 aryl, "aralkyl" means C6 to C20 aralkyl, "alkylene" means C1 to C20 alkylene, "arylene" means C6 to C20 arylene, "alkylarylene" means C6 to C20 alkylarylene, "heteroarylene" means C3 to C20 heteroarylene, and "alkyleneoxy" means C1 to C20 alkyleneoxy.

In the present specification, when a specific definition is not otherwise provided, "substituted" means that at least one hydrogen is replaced by: halogen atoms (F, Cl, Br, or I), hydroxyl groups, C1 to C20 alkoxy groups, nitro groups, cyano groups, amine groups, imino groups, azido groups, carbamimidoyl groups, hydrazino groups, hydrazonoyl groups, carbonyl groups, carbamoyl groups, thiol groups, ester groups, ether groups, carboxyl groups or salts thereof, sulfonic acid groups or salts thereof, phosphoric acid or salts thereof, C1 to C20 alkyl groups, C2 to C20 alkenyl groups, C2 to C20 alkynyl groups, C6 to C20 aryl groups, C3 to C20 cycloalkyl groups, C3 to C20 cycloalkenyl groups, C3 to C20 cycloalkynyl groups, C2 to C20 heterocycloalkyl groups, C2 to C20 heterocycloalkenyl groups, C2 to C20 heterocycloalkynyl groups, C3 to C20 heteroaryl groups, or combinations thereof.

In the present specification, when a specific definition is not otherwise provided, "hetero" may mean one substituted by N, O, S and at least one heteroatom of P in the chemical formula.

In the present specification, "(meth) acrylate" means "acrylate" and "methacrylate", and "(meth) acrylic acid" means "acrylic acid" and "methacrylic acid", when a specific definition is not otherwise provided.

In the present specification, "combination" means mixing or copolymerization when a specific definition is not otherwise provided.

In the present specification, unless a specific definition is otherwise provided, when a chemical bond is not drawn, a hydrogen atom is bonded at a presumably given position.

In the present specification, "+" indicates a point connecting the same or different atoms or chemical formulae, when a specific definition is not otherwise provided.

The solvent-free curable composition according to the embodiment includes (a) quantum dots; (B) a polymerizable monomer; and (C) a light diffusing agent, and not including a solvent, wherein the light diffusing agent has a primary particle diameter of 50 nm to 200 nm and a secondary particle diameter of 120 nm to 250 nm.

In general, the curable composition is composed of a pigment or dye, a photopolymerizable monomer, a binder resin, a photopolymerization initiator, a solvent, an additive, and the like, but the curable composition according to the embodiment uses inorganic quantum dots (without using the pigment or dye) to impart color characteristics, and thus, since a color filter manufactured using the solvent-free curable composition according to the embodiment has photoluminescence and has higher luminance, higher efficiency for reducing power consumption, a wider viewing angle, and higher color reproducibility than a color filter manufactured using a conventional curable composition, and thus, may ultimately contribute to the development of an LCD having the above properties.

On the other hand, the curable composition according to the example is a solvent-free composition containing no solvent at all. Since vinyl monomers (each including monofunctional to polyfunctional vinyl monomers, acrylate monomers, methacrylate monomers, and the like), which are polymerizable monomers generally and widely used in curable compositions containing quantum dots, have insufficient dispersibility with respect to highly concentrated quantum dots, curable compositions containing quantum dots have been developed to include a large amount (50 wt% or more) of solvent, but when the amount of solvent is increased, there is a problem in that inkjet processability is deteriorated. Accordingly, in order to satisfy inkjet processability, a demand for a solvent-free curable composition is increased, and thus, embodiments relate to a solvent-free curable composition containing quantum dots that satisfies the increased demand. In other words, the composition according to the embodiment includes quantum dots but does not include a solvent at all, and thus can prevent degradation of inkjet processability, and at the same time, realize a color filter having excellent light efficiency.

In addition, for solvent-free curable compositions containing quantum dots, storage stability and inkjet characteristics are also very important. In order to achieve inkjet characteristics, the composition requires a very low viscosity of 30cPs or less, but a light diffuser included in a solvent-free curable composition containing quantum dots has a high density and may be easily precipitated, and thus has a negative effect on long product storage stability.

The light diffuser may play a role in more efficiently using the photoluminescence properties of the quantum dots, but a technique of simultaneously improving the optical characteristics and precipitation characteristics of the light diffuser in a solvent-free curable composition containing quantum dots has not been introduced. The improved techniques known so far do not involve light diffusers but rather increased compatibility between monomers with high polarity and quantum dots modified by the surface of the quantum dots.

According to an embodiment, the light diffuser used in conjunction with the quantum dot is limited to have a primary particle diameter and a secondary particle diameter each ranging from 50 nm to 200 nm and from 120 nm to 250 nm to reduce the density, and thus solve the precipitation problem while also maximizing the scattering effect on the quantum dot (see fig. 1).

In particular, when the light diffusing agent is limited to have a primary particle diameter in the range of 50 to 200 nm and, at the same time, a secondary particle diameter in the range of 120 to 250 nm, the precipitation problem can be solved. In other words, when the solvent-free composition dispersed in the polymerizable monomer is redispersed by the light diffuser limited to have a primary particle diameter within the range, the composition is rapidly redispersed in a short time and thus the precipitation rate is slowed. When the light diffusing agent has a primary particle diameter of less than 50 nm, precipitation characteristics may be improved, but light absorption and light conversion may be deteriorated (regardless of controlling the secondary particle diameter). In addition, when the light diffusing agent has a secondary particle diameter of more than 250 nm, optical characteristics may be improved, but the particle size is too large, and thus the precipitation rate is accelerated, and thus has a negative influence on the roughness of the surface of the light diffusing agent particles.

In addition, when the light diffusing agent is controlled to have a primary particle diameter within the above range and simultaneously have a secondary particle diameter within the range of 120 nm to 250 nm, the precipitation rate may be slowed and the optical characteristics, and in particular, the blue light absorption rate and the blue light conversion rate may be maximized.

Hereinafter, each component is specifically described.

(C) Light diffusing agent

As described above, based on D₅₀For reference, the light diffusing agent has a primary particle diameter of 50 nm to 200 nm and a secondary particle diameter of 120 nm to 250 nm. For example, the light diffusing agent may have a primary particle diameter of 80 to 180 nanometers and a secondary particle diameter of 140 to 230 nanometers. The solvent-free curable composition according to the embodiment can achieve optimal optical characteristics and precipitation characteristics by controlling the primary particle diameter and the secondary particle diameter of the light diffuser.

The secondary particle diameter means a diameter of agglomerated particles of the light diffuser powder by properly dispersing the light diffuser powder having the primary particle diameter, and the primary particle diameter and the secondary particle diameter can be controlled to simultaneously improve optical characteristics and precipitation characteristics of the solvent-free curable composition containing the quantum dots.

When the light diffusing agent has a primary particle diameter and a secondary particle diameter each in the range of less than 50 nm (e.g., 80 nm) and less than 120 nm (e.g., 140 nm), the optical characteristics may be drastically deteriorated, and when the light diffusing agent has a primary particle diameter and a secondary particle diameter each in the range of more than 200 nm (e.g., 180 nm) and more than 250 nm (e.g., 230 nm), the precipitation characteristics may be drastically deteriorated.

For example, the secondary particle diameter of the light diffusing agent may be 1.5 times to 2.5 times (e.g., 1.5 times to twice) larger than the primary particle diameter of the light diffusing agent. When the light diffusing agent has a primary particle diameter and a secondary particle diameter within the ranges, both the optical characteristics and the precipitation characteristics can be very effectively improved.

In addition, different crystalline phases of the light diffusing agent, and thus its different density, can be used to control the precipitation characteristics.

Generally, TiO used as a light diffuser₂Has two distinct crystalline phases. One is the anatase type and the other is the rutile type, with the anatase type having a density of 3.8 g/ml and the rutile type having a relatively high density of 4.2 g/ml.

With regard to density, the crystalline phases have a difference in refractive index and thus a difference in scattering intensity, and a material having a higher refractive index and thus a stronger scattering intensity may not act as a scatterer.

In other words, when the anatase type has a refractive index of 2.5, the rutile type has a refractive index of 2.7, and thus both have the same particle distribution, the rutile type exhibits a higher absorption rate than the scatterer but has a higher density than the anatase type, and therefore, the precipitation characteristics of the rutile type may be more deteriorated than those of the anatase type.

Thus, the anatase type or the rutile type having the aforementioned primary particle diameter range and secondary particle diameter range can realize improved precipitation characteristics when used as a mixture and when used alone.

For example, the light diffusing agent may be a mixture of a rutile type light diffusing agent and an anatase type light diffusing agent. In this context, the rutile type light diffuser and the anatase type light diffuser may be used in a weight ratio of 1:3 to 3:1 (e.g., 1:1 to 1: 3). For example, the anatase light diffusing agent in the mixture may be included in a greater amount than the rutile light diffusing agent. Herein, both the optical properties and the precipitation properties can be achieved more efficiently.

For example, the light diffuser may comprise barium sulfate (BaSO)₄) Calcium carbonate (CaCO)₃) Titanium dioxide (TiO)₂) Zirconium oxide (ZrO)₂) Or a combination thereof.

For example, the light diffuser may be titanium dioxide (TiO)₂) For example rutile titanium dioxide, anatase titanium dioxide or a mixture of rutile titanium dioxide and anatase titanium dioxide. Titanium dioxide has a relatively high refractive index and, therefore, can increase the photoluminescent efficiency of quantum dots in solvent-free curable compositions.

The light diffusing agent may reflect light that is not absorbed in the quantum dots, and cause the reflected light to be absorbed again in the quantum dots. In other words, the light diffuser may increase the amount of light absorbed in the quantum dots, and thus increase the light conversion rate of the quantum dots in the solvent-free curable composition. In other words, since the color filter process is continued, the deterioration of the blue light conversion rate can be prevented.

The light diffuser may be included in an amount of 1 to 20 wt% (e.g., 5 to 10 wt%), based on the total amount of the solvent-free curable composition. When the light diffusing agent is contained in an amount of less than 1% by weight based on the total amount of the solvent-free curable composition, it is difficult to expect a light conversion efficiency improving effect due to the use of the light diffusing agent, whereas when the light diffusing agent is contained in an amount of more than 20% by weight, there is a possibility that quantum dots may be precipitated.

(A) Quantum dots

The quantum dots can absorb light in a wavelength range of 360 nanometers to 780 nanometers (e.g., a wavelength range of 400 nanometers to 780 nanometers) and emit fluorescence in a wavelength range of 450 nanometers to 700 nanometers. That is, the quantum dots may have a maximum fluorescence emission wavelength (fluorescence λ) at 450 nm to 700 nm_em)。

In particular, the quantum dots can be of a wavelength having a maximum fluorescence emission wavelength (fluorescence λ) between 450 nm and 580 nm_em) And has a maximum fluorescence emission wavelength (fluorescence lambda) of 580 to 700 nm_em) Quantum dots (e.g., red quantum dots), or combinations thereof.

The green light quantum dots may have an average particle diameter of 5 to 10 nanometers, and the red light quantum dots may have an average particle diameter of 7 to 15 nanometers.

The quantum dots can have a full width at half maximum (FWHM) of 20 to 100 nanometers (e.g., 20 to 80 nanometers, such as 40 to 60 nanometers). When the quantum dot has a full width at half maximum (FWHM) of the range, color reproducibility is increased when used as a material in a color filter due to high color purity.

The quantum dots may be organic materials, inorganic materials, or hybrids (mixtures) of organic and inorganic materials.

The quantum dot may be composed of a core and a shell surrounding the core, and the core and the shell may each independently have a structure of a core, a core/shell, a core/first shell/second shell, an alloy/shell, and the like, which are composed of groups II to IV, III to V, and the like, but is not limited thereto.

For example, the core may comprise at least one material selected from the group consisting of: CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, GaN, GaP, GaAs, InP, InAs, and alloys thereof, but not necessarily limited thereto. The shell surrounding the core may comprise at least one material selected from the group consisting of: CdSe, ZnSe, ZnS, ZnTe, CdTe, PbS, TiO, SrSe, HgSe, and alloys thereof, but not necessarily limited thereto.

The structure of the quantum dot is not particularly limited, but the quantum dot having a core/shell structure may have an overall size (average particle diameter) including a shell in a range of 1 to 15 nm (e.g., 5 to 10 nm).

In order to improve stability and dispersion of the quantum dot, the quantum dot may be stabilized by substituting an organic material on the surface of the shell layer, and the organic material may include thiol compounds, amine compounds, phosphine oxide compounds, acryl compounds, silicon compounds, and the like, but is not limited thereto.

In the embodiment, since the attention on the environment is greatly increased and the limitation on toxic materials is also strengthened in the present world, a cadmium-free luminescent material having a cadmium-based core, but not necessarily a cadmium-free luminescent material, such as InP/ZnS core/shell type quantum dots, InP/ZnSe/ZnS core/first shell/second shell type quantum dots, which is extremely low in quantum efficiency (quantum yield) but environmentally friendly, is used.

On the other hand, the solvent-free type curable composition according to the embodiment may further include a dispersant with respect to dispersion stability of the quantum dot. The dispersant contributes to uniform dispersibility of the light conversion material, such as quantum dots in a solventless curable composition, and may include a nonionic, anionic or cationic dispersant. Specifically, the dispersant may be a polyalkylene glycol or an ester thereof, a polyoxyalkylene (polyoxyalkylene), a polyol ester alkylene oxide addition product, an alcohol alkylene oxide addition product, a sulfonate, a carboxylic ester, a carboxylic acid salt, an alkylamide alkylene oxide addition product, an alkylamine, or the like, and it may be used alone or in a mixture of two or more. The dispersant may be used in an amount of 0.1 to 100 wt% (e.g., 10 to 20 wt%) relative to the solid content of the light conversion material such as the quantum dot.

The quantum dots may be included in an amount of 1 to 40 wt% (e.g., 3 to 30 wt%), based on the total amount of the solvent-free curable composition. When the surface-modified quantum dot is included in the range, a light conversion rate may be improved without interfering with pattern characteristics and developing characteristics, so that it may have excellent processability.

(B) Polymerizable monomer

The polymerizable monomer may be a monofunctional or polyfunctional ester of (meth) acrylic acid containing at least one ethylenically unsaturated double bond.

The polymerizable monomer has an ethylenically unsaturated double bond, and therefore can cause sufficient polymerization during exposure in the pattern forming process, and form a pattern having excellent heat resistance, light resistance, and chemical resistance.

Specific examples of the polymerizable monomer may be ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1, 4-butanediol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, bisphenol a di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol hexa (meth) acrylate, dipentaerythritol di (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol a epoxy (meth) acrylate, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, pentaerythritol, Ethylene glycol monomethyl ether (meth) acrylate, trimethylolpropane tri (meth) acrylate, tris (meth) acryloyloxyethyl phosphate, novolac epoxy (meth) acrylate, and the like.

Commercially available examples of the polymerizable monomer are as follows. The monofunctional (meth) acrylate may comprise anix (Aronix)

Anixex

Anixex

(Toagosei Chemistry Industry Co., Ltd.); kayalard (KAYARAD)

Kayalard

(Nippon Kayaku Co., Ltd.,. Ltd.);

(Osaka Organic Chemical industry Co., Ltd., (Ltd.)) and the like. Examples of difunctional (meth) acrylates may include anixox

Anixex

Anixex

(Toyo Synthesis chemical industry Co., Ltd.); kayalard

Kayalard

Kayalard

(Nippon Kagaku Co., Ltd.);

(Osaka organic chemical industries Co., Ltd.) and the like. Examples of trifunctional (meth) acrylates may include anixox

Anixex

Anixex

Anixex

Anixex

Anixex

Anixex

(Toyo Synthesis chemical industry Co., Ltd.); kayalard

Kayalard

Kayalard

Kayalard

Kayalard

(Nippon Kagaku Co., Ltd.);

(Osaka, Shibata, Kyowa Yuki Kayaku Kogyo Co. Ltd.) and the like. These may be used alone or in a mixture of two or more.

Further, in addition to the polymerizable monomer, a monomer generally used in a conventional thermosetting or photocurable composition may be further used. For example, the monomer additionally used may be an oxetane compound, such as bis [ 1-ethyl (3-oxetanyl) ] methyl ether.

The polymerizable monomer may be treated with an acid anhydride to improve developability.

The polymerizable monomer may be included in an amount of 40 to 80 wt% (e.g., 50 to 80 wt%) based on the total amount of the solvent-free curable composition. When the polymerizable monomer is included in the range, a solvent-free curable composition having a viscosity capable of inkjet may be prepared, and the quantum dots in the prepared solvent-free curable composition may have improved dispersibility, thereby improving optical characteristics.

In addition, the polymerizable monomer may have a weight average molecular weight of 220 g/mole to 1,000 g/mole. When the polymerizable monomer has a molecular weight within the range, ink jetting may be facilitated because it does not increase the viscosity of the composition without hindering the optical characteristics of the quantum dot.

Polymerization initiator

The solvent-free curable composition according to an embodiment may further include a polymerization initiator, such as a photopolymerization initiator, a thermal polymerization initiator, or a combination thereof.

The photopolymerization initiator is a common initiator for photosensitive resin compositions, and examples thereof include, but are not limited to, acetophenone compounds, benzophenone compounds, thioxanthone compounds, benzoin compounds, triazine compounds, oxime compounds, and aminoketone compounds.

Examples of the acetophenone compounds may be 2,2' -diethoxyacetophenone, 2' -dibutoxyacetophenone, 2-hydroxy-2-methylpropiophenone, p-tert-butyltrichloroacetophenone, p-tert-butyldichloroacetophenone, 4-chloroacetophenone, 2' -dichloro-4-phenoxyacetophenone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, and the like.

Examples of the benzophenone-based compound may be benzophenone, benzoylbenzoate, benzoylmethyl benzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4' -bis (dimethylamino) benzophenone, 4' -bis (diethylamino) benzophenone, 4' -dimethylaminobenzophenone, 4' -dichlorobenzophenone, 3' -dimethyl-2-methoxybenzophenone and the like.

Examples of the thioxanthone-based compound may be thioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2, 4-diethylthioxanthone, 2, 4-diisopropylthioxanthone, 2-chlorothioxanthone, and the like.

Examples of benzoin-based compounds may be benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, and the like.

Examples of triazines are 2,4, 6-trichloro-s-triazine, 2-phenyl-4, 6-bis (trichloromethyl) -s-triazine, 2- (3',4' -dimethoxystyryl) -4, 6-bis (trichloromethyl) -s-triazine, 2- (4' -methoxynaphthyl) -4, 6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4, 6-bis (trichloromethyl) -s-triazine, 2- (p-tolyl) -4, 6-bis (trichloromethyl) -s-triazine, 2-biphenyl-4, 6-bis (trichloromethyl) -s-triazine, bis (trichloromethyl) -6-styryl-s-triazine, 2- (naphthol-yl) -4, 6-bis (trichloromethyl) -s-triazine, 2- (4-methoxynaphthol-yl) -4, 6-bis (trichloromethyl) -s-triazine, 2-4-bis (trichloromethyl) -6-piperonyl (piperonyl) -s-triazine, 2-4-bis (trichloromethyl) -6- (4-methoxystyryl) -s-triazine and the like.

Examples of the oxime compound may be O-acyloxime compound (O-acyloxime-based compound), 2- (O-benzoyloxime) -1- [4- (phenylthio) phenyl ] -1, 2-octanedione, 1- (O-acetyloxime) -1- [ 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] ethanone, O-ethoxycarbonyl-alpha-oxyamino-1-phenylpropan-1-one, and the like. Specific examples of O-acyloximes are 1, 2-octanedione, 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one, 1- (4-phenylthiophenyl) -butane-1, 2-dione 2-oxime-O-benzoate, 1- (4-phenylthiophenyl) -octane-1, 2-dione 2-oxime-O-benzoate, 1- (4-phenylthiophenyl) -octan-1-one oxime-O-acetate, 1- (4-phenylthiophenyl) -butane-1-one oxime-O-acetate, and the like.

Examples of the aminoketones are 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 and the like.

The photopolymerization initiator may further contain, in addition to the above-mentioned compounds, carbazole-based compounds, diketone-based compounds, sulfonium borate-based compounds, diazonium-based compounds, imidazole-based compounds, bisimidazole-based compounds, and the like.

The photopolymerization initiator may be used together with a photosensitizer capable of causing a chemical reaction by absorbing light and becoming an excited state and then transferring its energy.

Examples of the sensitizer may be tetraethylene glycol bis-3-mercaptopropionate, pentaerythritol tetrakis-3-mercaptopropionate, dipentaerythritol tetrakis-3-mercaptopropionate, and the like.

Examples of the thermal polymerization initiator may be peroxides, specifically benzoyl peroxide, dibenzoyl peroxide, lauroyl peroxide (lauryl peroxide), dilauroyl peroxide (dilauryl peroxide), di-t-butyl peroxide (di-tert-butyl peroxide), cyclohexane peroxide, methyl ethyl ketone peroxide, hydroperoxides (e.g., tert-butyl hydroperoxide (tert-butyl hydroperoxide), cumene hydroperoxide), dicyclohexyl peroxydicarbonate (dicyclohexyl peroxydicarbonate), 2-azo-bis (isobutyronitrile), tert-butyl perbenzoate, and analogs such as 2,2 '-azobis-2-methylpropionitrile (2,2' -azobis-2-methylpropionitrile), but are not necessarily limited thereto and any of the peroxides well known in the art may be used.

The polymerization initiator may be included in an amount of 0.1 to 5 wt% (e.g., 1 to 4 wt%) based on the total amount of the solvent-free curable composition. When the polymerization initiator is included in the range, it is possible to obtain excellent reliability due to sufficient curing during exposure or thermal curing, and it is possible to prevent deterioration of transmittance due to a non-reactive initiator, thereby preventing deterioration of optical characteristics of the quantum dot.

Other additives

The solvent-free curable composition according to the embodiment may further include a polymerization inhibitor for stability and dispersion improvement of the quantum dot.

The polymerization inhibitor may comprise a hydroquinone compound, a catechol compound, or a combination thereof, but is not necessarily limited thereto. When the solvent-free curable composition according to the embodiment further includes a hydroquinone compound, a catechol compound, or a combination thereof, room temperature crosslinking during exposure after coating the solvent-free curable composition may be prevented.

For example, the hydroquinone compound, the catechol compound, or the combination thereof may be hydroquinone, methyl hydroquinone, methoxy hydroquinone, t-butyl hydroquinone, 2, 5-di-t-butyl hydroquinone, 2, 5-bis (1, 1-dimethylbutyl) hydroquinone, 2, 5-bis (1,1,3, 3-tetramethylbutyl) hydroquinone, catechol, t-butyl catechol, 4-methoxy phenol, pyrogallol, 2, 6-di-t-butyl-4-methylphenol, 2-naphthol, tris (N-hydroxy-N-nitrosophenylamine-O, O') aluminum, or a combination thereof, but is not necessarily limited thereto.

The hydroquinone compound, the catechol compound, or a combination thereof may be used in the form of a dispersion (dispersion). The polymerization inhibitor may be included in the form of a dispersion in an amount of 0.001 to 3 wt% (e.g., 0.1 to 2 wt%) based on the total amount of the solvent-free curable composition. When the polymerization inhibitor is included in the range, the time lapse problem at room temperature can be solved and at the same time, the sensitivity deterioration and the surface delamination phenomenon can be prevented.

In addition, the solvent-free curable composition according to the embodiment may further include malonic acid; 3-amino-1, 2-propanediol; a silane-based coupling agent; a leveling agent; a fluorine-based surfactant; or a combination thereof to improve heat resistance and reliability.

For example, the solvent-free type curable composition according to the embodiment may further include a silane-based coupling agent having a reactive substituent (e.g., a vinyl group, a carboxyl group, a methacryloxy group, an isocyanate group, an epoxy group, etc.) to improve the close contact property with the substrate.

Examples of the silane-based coupling agent may be trimethoxysilylbenzoic acid, gamma-methylpropenylpropoxyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, gamma-isocyanatopropyltriethoxysilane, gamma-glycidoxypropyltrimethoxysilane, beta-epoxycyclohexyl) ethyltrimethoxysilane, etc., and these may be used alone or in a mixture of two or more.

The silane-based coupling agent may be used in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the solvent-free curable composition. When the silane-based coupling agent is contained within the range, the close contact property, the storage capacity, and the like are improved.

In addition, the solvent-free curable composition may further contain a surfactant such as a fluorine-based surfactant as necessary to improve coating properties and suppress spot generation, i.e., to improve leveling performance.

The fluorine-based surfactant may have a low weight average molecular weight of 4,000 g/mole to 10,000 g/mole, and specifically 6,000 g/mole to 10,000 g/mole. In addition, the fluorine-based surfactant may have a surface tension of 18 to 23 milli-newtons per meter (measured with a 0.1% Polyethylene Glycol Monomethyl Ether Acetate (PGMEA) solution). When the fluorine-based surfactant has a weight average molecular weight and a surface tension within the ranges, leveling properties can be further improved and excellent characteristics can be provided when slit coating as high-speed coating is applied, since film defects can be less generated by preventing generation of spots during high-speed coating and suppressing generation of vapor.

An example of the fluorine-based surfactant may be

And

(BM Chemie Inc.)); megafield (MEGAFACE) F

Megaffei F

Megaffei F

And Megoffes F

(Dainippon Ink chemical industry Co., Ltd. (Dainippon Ink Kagaku Kogyo Co., Ltd.)); folerlade (FULORAD)

Fowler radde

Fowler radde

And Fowler-red

(Sumitomo 3M Co., Ltd.); dragons (SURFLON)

Cable dragon

Cable dragon

Cable dragon

And a cable dragon

(Asahi Glass Co., Ltd.); and

and

etc. (Toray Silicone Co., Ltd.); f-482, F-484, F-478, and F-554 from Dainippon ink chemical industries, Ltd.

In addition, the solvent-free type curable composition according to the embodiment may further include a silicone type surfactant in addition to the fluorine type surfactant. Specific examples of the silicone-based surfactant may be TSF400, TSF401, TSF410, TSF4440, and the like, of Toshiba silicone co.

The surfactant may be included in an amount of 0.01 parts by weight to 5 parts by weight (e.g., 0.1 parts by weight to 2 parts by weight) based on 100 parts by weight of the solvent-free curable composition. When the surfactant is contained in the range, foreign substances are less generated in the sprayed composition.

In addition, the solvent-free curable composition according to the embodiment may further include predetermined amounts of other additives, such as antioxidants, stabilizers, and the like, unless the properties are deteriorated.

Another embodiment provides a cured film manufactured using the aforementioned solvent-free curable composition, a color filter including the cured film, and a display device including the color filter.

One of the methods of producing the cured layer may include: coating the aforementioned solvent-free curable composition on a substrate using an inkjet spray method to form a pattern (S1); and curing the pattern (S2).

(S1) Pattern formation

The solventless curable composition can be desirably coated on a substrate from 0.5 microns to 20 microns using an inkjet spray process. The inkjet spray method can form a pattern by spraying a single color according to each nozzle and thus repeatedly spraying a number of times according to the number of desired colors, but a pattern can be formed by simultaneously spraying the number of desired colors through each inkjet nozzle to reduce processes.

(S2) curing

The obtained pattern is cured to obtain pixels. Herein, the curing method may be a thermal curing or photo curing process. The thermal curing process may be conducted at greater than 100 ℃ or equal to 100 ℃, desirably in the range of 100 ℃ to 300 ℃, and more desirably in the range of 160 ℃ to 250 ℃. The photocuring process can include irradiating actinic radiation, such as ultraviolet light from 190 nm to 450 nm (e.g., from 200 nm to 500 nm). The irradiation is performed by using a light source such as a mercury lamp, a metal halide lamp, an argon laser, or the like having a low pressure, a high pressure, or an ultrahigh pressure. X-rays, electron beams, etc. may also be used as necessary.

Hereinafter, the present invention is described in more detail with reference to examples. However, these examples should not be construed in any way as limiting the scope of the invention.

(preparation of solvent-free curable composition)

Examples 1 to 9 and comparative examples 1 and 7

The following components were used to prepare solvent-free curable compositions according to examples 1 to 9 and comparative examples 1 and 2 having the compositions shown in table 1 and table 2, respectively.

Specifically, a quantum dot dispersion (solid content of 26 to 27 wt%) dispersed in cyclohexyl acetate in a flask was stirred under a nitrogen atmosphere at 80 ℃ for 20 hours to obtain a surface-modified quantum dot dispersion. The resulting product was cooled to room temperature and the quantum dot dispersion was added to cyclohexane and then centrifuged. The precipitated quantum dot powder was separated from cyclohexane by centrifugation. The clear solution in the upper part was discarded and the precipitate was dried in a vacuum oven for 24 hours. The quantum dot powder was sampled to HDDA (1, 6-hexanediol diacrylate) monomer at a predetermined concentration, and then stirred for 12 hours to obtain a quantum dot dispersion.

Subsequently, the quantum dot dispersion was weighed, HDDA was added thereto, and then stirred for 5 hours, a polymerization initiator was added thereto, and a light diffusing agent was added thereto. The whole dispersion was stirred for 1 hour to prepare a solvent-free type curable composition.

(A) Quantum dots

InP/ZnSe/ZnS quantum dot dispersion (quantum dot solid content 30%, fluorescence lambda)_em630 nm, FWHM 40 nm to 60 nm, red QD, korean Chemical co, Ltd).

(B) Polymerizable monomer

1, 6-hexanediol diacrylate (HDDA, Miwon Specialty Chemicals Co., Ltd.)

(C) Light diffusing agent

(C-1) rutile titanium dioxide Dispersion (40% by weight TiO in HDDA)₂Solid content, primary particle diameter: 50 nm, secondary particle diameter: 120 nm, NJ 660, Mikuni Corp., Mikuni)

(C-2) rutile titanium dioxide Dispersion (40% by weight TiO in HDDA)₂Solid content, primary particle diameter: 80 nm, secondary particle diameter: 140 nm, NJ 672, three kingdoms company)

(C-3) rutile titanium dioxide Dispersion (40% by weight TiO in HDDA)₂Solid content, primary particle diameter: 100 nm, next toGrade particle diameter: 150 nm, NJ 661, three kingdoms, Inc.)

(C-4) anatase titanium dioxide Dispersion (50% by weight TiO in HDDA)₂Solid content, primary particle diameter: 160 nm, secondary particle diameter: 170 nm, A16, Iridoss Co., Ltd.))

(C-5) rutile titanium dioxide Dispersion (50% by weight TiO in HDDA)₂Solid content, primary particle diameter: 170 nm, secondary particle diameter: 185 nanometer, white NS-13H, Ill Dos Co., Ltd.)

(C-6) rutile titanium dioxide Dispersion (50% by weight TiO in HDDA)₂Solid content, primary particle diameter: 210 nm, secondary particle diameter: 210 nm, TiO2-7, Ill duo Si Co., Ltd.)

(C-7) rutile titanium dioxide Dispersion (50% by weight TiO in HDDA)₂Solid content, primary particle diameter: 250 nm, secondary particle diameter: 230 nm, TiO2-9, Elliosis Inc.)

(C-8) rutile titanium dioxide Dispersion (50% by weight TiO in HDDA)₂Solid content, primary particle diameter: 270 nm, secondary particle diameter: 280 nm, TiO2-22, Elliosis Inc.)

Polymerization initiator

Ethyl (2,4,6-trimethylbenzoyl) phenylphosphonite (Ethyl (2,4, 6-trimethylbenzolyl) phenylphosphonate) (IGM resin)

Other additives

Fluorine surfactant (F-554, Dainippon ink chemical Co., Ltd.)

(Table 1)

(unit: wt%)

(Table 2)

(unit: wt%)

Evaluation 1: evaluation of optical Properties

The compositions according to examples 1 to 9 and comparative examples 1 and 2 were coated on glass substrates to a thickness of 15 μm, respectively, by using a spin coater (Opticoat MS-a150, 800 rpm, 5 seconds, manufactured by sank corporation (Mikasa co., Ltd.), and then exposed to light having 5000 mj under a nitrogen atmosphere by using a UV exposure device of 395 nm. Subsequently, a single-layer film specimen of 2 cm × 2 cm was loaded on an integrating sphere device (QE-2100, tsukamur Electronics co., Ltd.)) to measure the blue light conversion rate, and the measurement results are shown in table 3.

Evaluation 2: evaluation of precipitation

20 ml of each composition according to examples 1 to 9 and comparative examples 1 and 2 were allowed to stand at room temperature for 10 days. In this context, the precipitate is due to TiO₂The degree of precipitation relative to the reference (example 6) composition was obtained as%, and the results are shown in table 3. Fig. 2 and 3 are graphs of X-ray analysis of crystal phases of the light diffusing agents used in example 5 and example 4, respectively.

(Table 3)

	Blue light conversion (%)	Degree of precipitation (relative to reference) (%)
			Example 1	28.3	-81
Example 2	29.1	-75
			Example 3	29.5	-67
Example 4	29.9	-39
			Example 5	29.5	-32
Example 6	29.3	0 (ref)
			Example 7	29.5	-33
Example 8	29.6	-33
			Example 9	29.8	-35
Comparative example 1	29.2	15
			Comparative example 2	29.4	40

Referring to table 3, when the primary particle diameter and the secondary particle diameter of the light diffusing agent are controlled within specific ranges, both the optical characteristics and the precipitation characteristics are improved as compared with the case of using a light diffusing agent not having the primary particle diameter and the secondary particle diameter within the ranges. In addition, when a composition including a light diffusing agent having a particle diameter within a controlled range and thus having a mixed crystal phase of a rutile type and an anatase type includes more anatase types than the rutile type, excellent optical characteristics and precipitation characteristics are achieved.

While the invention has been described in connection with what is presently considered to be practical example embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The foregoing embodiments are therefore to be considered in all respects illustrative rather than limiting of the invention.

Claims

1. A solventless curable composition comprising

(A) Quantum dots;

(B) a polymerizable monomer; and

(C) a light diffusing agent having a primary particle diameter of 50 nm to 200 nm and a secondary particle diameter of 120 nm to 250 nm.

2. The solvent-free curable composition according to claim 1, wherein the light diffuser has a primary particle diameter of 80 to 180 nm and a secondary particle diameter of 140 to 230 nm.

3. The solvent-free curable composition according to claim 1, wherein the secondary particle size of the light diffusing agent has a size of 1.5 times to 2.5 times the primary particle size of the light diffusing agent.

4. The solvent-free curable composition according to claim 1, wherein the light diffuser is a mixture of a rutile type light diffuser and an anatase type light diffuser.

5. The solvent-free curable composition according to claim 4, wherein the rutile light diffuser and the anatase light diffuser are included in the mixture in a weight ratio of 1:3 to 3: 1.

6. The solvent-free curable composition of claim 1, wherein the light diffuser comprises barium sulfate, calcium carbonate, titanium dioxide, zirconium oxide, or a combination thereof.

7. The solvent-free curable composition of claim 1 wherein the quantum dots comprise quantum dots having a maximum fluorescence emission wavelength at 450 to 580 nanometers, quantum dots having a maximum fluorescence emission wavelength at 580 to 700 nanometers, or a combination thereof.

8. The solventless curable composition of claim 1 wherein the solventless curable composition further comprises a polymerization initiator.

9. The solventless curable composition of claim 1 wherein the solventless curable composition further comprises a polymerization inhibitor; malonic acid; 3-amino-1, 2-propanediol; a silane-based coupling agent; a leveling agent; a fluorine-based surfactant; or a combination thereof.

10. A cured film produced using the solvent-free curable composition according to any one of claims 1 to 9.

11. A color filter comprising the cured film of claim 10.

12. A display device comprising the color filter according to claim 11.