KR20200106437A - Light Scattering Ink Composition, Color Filter and Display Device - Google Patents

Abstract

The present invention relates to a light scattering ink composition comprising: a curable monomer; and scattering particles, wherein the curable monomer includes a bi-functional (meth)acrylate having a specific structure and tri- to tetra-functional (meth)acrylate having a specific structure at a specific mixing ratio, to a color filter formed using the same, and to an image display device comprising the color filter. The light scattering ink composition according to the present invention has excellent dispersibility of scattering particles, thereby improving jetting properties, and improving coating film hardness and surface properties. Therefore, the light scattering ink composition according to the present invention can be effectively used to manufacture a color filter by an inkjet printing method.

Description

Light Scattering Ink Composition, Color Filter and Display Device}

The present invention relates to a light-scattering ink composition, a color filter, and an image display device, and more particularly, to a light-scattering ink composition having excellent dispersibility of scattering particles, improving jetting, and improving hardness and surface properties of a coating film, It relates to a color filter formed by using and an image display device including the color filter.

Color filters are widely used in imaging devices, liquid crystal displays (LCDs), and the like, and their application range is expanding.

Recently, as one of the methods of implementing a color filter, a pigment dispersion method using a pigment dispersion type photosensitive resin has been applied, but a part of the light is absorbed by the color filter while the light irradiated from the light source passes through the color filter, resulting in light efficiency. There is a problem in that the color reproducibility is deteriorated and the color reproducibility is deteriorated due to the characteristics of the pigment included in the color filter.

As a solution to this problem, a color filter using quantum dots has been proposed. For example, Korean Patent Laid-Open No. 10-2009-0036373 discloses that the display quality of a display device can be improved by improving luminous efficiency by replacing an existing color filter with a light emitting layer made of a quantum dot phosphor.

However, in the case of a color filter including a quantum dot, the performance of the color filter may be slightly lowered as the efficiency of the quantum dot, especially the blue quantum dot, decreases, and there is a problem in that the overall manufacturing cost increases because the blue quantum dot is expensive. .

Accordingly, a light source that emits blue light is used, and a red pattern layer containing red quantum dot particles and a green pattern layer containing green quantum dot particles are provided, but the position corresponding to the blue pattern layer is transparent without quantum dot particles. With a pattern layer, red quantum dot particles emit red light, green quantum dot particles emit green light, and a transparent pattern layer transmits blue light as it is, indicating blue color.

Such a transparent pattern layer is mainly produced by a photolithography method using a photosensitive resin composition containing scattering particles. In the photolithography method, photolithography and development of a light shielding material thin film are used to form a barrier rib pattern, and a photosensitive resin is applied on the barrier rib by spin coating or slit coating, followed by patterning and curing by photolithography and development. It is a manufacturing method. This method has the advantage that the applied film thickness is uniform, but there is a loss of removing about 70% of the material to be applied during pattern formation, and expensive installation costs such as an exposure machine, a developer, and a curing device are required. Also, since the process line is long, it is difficult to manage the yield. In recent years, as the display material substrate becomes larger, the cost of the process and installation equipment is expected to increase further.

As an alternative to this, there is an inkjet method. The inkjet method is a technology in which an ink composition is sprayed only into an opening of a partition wall formed using an inkjet head to implement a pattern, and the manufacturing process, time, and cost can be greatly reduced. The inkjet method using such an ink composition satisfies a desired film thickness by spraying a specific amount of ink into the pixel openings of the partition walls.

However, since the existing ink composition is a solvent type containing an appropriate amount of solvent for ejection stability, even if it is printed with a certain film thickness, the film thickness becomes thin when dried, resulting in a problem in that the coating film hardness and surface characteristics are deteriorated.

In addition, when the scattering particles are prepared as a solvent-free composition, it is difficult to uniformly disperse the scattering particles, causing agglomeration of the scattering particles, resulting in an increase in viscosity, resulting in poor jetting properties.

Accordingly, there is an urgent need to develop an ink composition having excellent dispersibility of scattering particles without a solvent, improving jetting properties, and having excellent coating film hardness and coating film surface characteristics.

Korean Patent Publication No. 10-2009-0036373

An object of the present invention is to provide a light scattering ink composition having excellent dispersibility of scattering particles, improved jetting properties, and excellent coating hardness and coating surface properties.

Another object of the present invention is to provide a color filter formed using the light scattering ink composition.

Another object of the present invention is to provide an image display device including the color filter.

On the other hand, the present invention is a light scattering ink composition comprising a curable monomer and scattering particles, wherein the curable monomer comprises a compound represented by the following Formula 1 and a compound represented by the following Formula 2, and the compound represented by Formula 1 The mixing ratio of the compound represented by Formula 2 provides a light scattering ink composition of 40:60 to 80:20 in weight fraction.

[Formula 1]

[Formula 2]

In the above formula,

R ¹ is a C ₁ -C ₂₀ alkylene group,

R ² is hydrogen or a methyl group,

m is an integer from 1 to 6,

R ³ is hydrogen, a C ₁ -C ₆ alkyl group, a C ₁ -C ₆ hydroxyalkyl group, a hydroxy group, or a functional group represented by the following formula (3),

[Formula 3]

R ⁴ is hydrogen or a methyl group,

R ⁵ is a C ₁ -C ₂₀ alkylene group, a phenylene group or a C ₃ -C ₁₀ cycloalkylene group,

L is absent or a C ₁ -C ₆ alkylene group,

p, q, r and n are each independently an integer of 0 to 5,

t is 0 or 1.

In one embodiment of the present invention, the curable monomer may be included in an amount of 50 to 95% by weight based on 100% by weight of the total light scattering ink composition.

In one embodiment of the present invention, the scattering particles may include TiO ₂ .

In one embodiment of the present invention, the scattering particles may be included in an amount of 1 to 20% by weight based on 100% by weight of the total light scattering ink composition.

The light scattering ink composition according to an embodiment of the present invention may further include a photoinitiator.

The photoconversion ink composition according to an embodiment of the present invention may not contain a solvent.

On the other hand, the present invention provides a light-scattering pixel including a cured product of the light-scattering ink composition.

On the other hand, the present invention provides a color filter including the light scattering pixel.

On the other hand, the present invention provides an image display device provided with the color filter.

The light-scattering ink composition according to the present invention contains a bifunctional (meth)acrylate having a specific structure as a curable monomer and a 3 to tetrafunctional (meth)acrylate having a specific structure at a specific mixing ratio, so that the dispersibility of the scattering particles without a solvent is As it is excellent, the jetting property is improved, and the hardness of the coating film and the surface characteristics of the coating film are improved. Therefore, the light scattering ink composition according to the present invention can be effectively used to manufacture a color filter by inkjet printing.

Hereinafter, the present invention will be described in more detail.

One embodiment of the present invention includes a curable monomer (A) and a scattering particle (B), and the curable monomer (A) is a bifunctional (meth)acrylate having a specific structure, and a 3 to tetrafunctional (meth)acrylate having a specific structure (meta ) It relates to a light scattering ink composition comprising an acrylate together in a specific mixing ratio.

Curable monomer (A)

In one embodiment of the present invention, the curable monomer (A) includes a compound represented by the following formula (1) and a compound represented by the following formula (2).

[Formula 1]

[Formula 2]

In the above formula,

R ¹ is a C ₁ -C ₂₀ alkylene group,

R ² is hydrogen or a methyl group,

m is an integer from 1 to 6,

R ³ is hydrogen, a C ₁ -C ₆ alkyl group, a C ₁ -C ₆ hydroxyalkyl group, a hydroxy group, or a functional group represented by the following formula (3),

[Formula 3]

R ⁴ is hydrogen or a methyl group,

R ⁵ is a C ₁ -C ₂₀ alkylene group, a phenylene group or a C ₃ -C ₁₀ cycloalkylene group,

L is absent or a C ₁ -C ₆ alkylene group,

p, q, r and n are each independently an integer of 0 to 5,

t is 0 or 1.

The C ₁ -C ₂₀ alkylene group used herein refers to a straight-chain or branched divalent hydrocarbon consisting of 1 to 20 carbon atoms, for example methylene, ethylene, n-propylene, isopropylene, n-butyl Ethylene, isobutylene, n-pentylene, n-hexylene, n-heptylene, n-octylene, n-nonylene, and the like are included, but are not limited thereto.

The C ₃ -C ₁₀ cycloalkylene group used herein refers to a simple or fused cyclic divalent hydrocarbon consisting of 3 to 10 carbon atoms, for example, cyclopropylene, cyclobutylene, cyclopentylene, cyclohexylene And the like, but are not limited thereto.

The C ₁ -C ₆ alkyl group used herein refers to a straight-chain or branched monovalent hydrocarbon consisting of 1 to 6 carbon atoms, for example methyl, ethyl, n-propyl, i-propyl, n-butyl , i-butyl, t-butyl, n-pentyl, n-hexyl, and the like are included, but are not limited thereto.

The C ₁ -C ₆ hydroxyalkyl group used herein refers to a straight-chain or branched hydrocarbon having 1 to 6 carbon atoms substituted with a hydroxy group, for example, hydroxymethyl, hydroxyethyl, hydroxypropyl, etc. Included, but not limited thereto.

The C ₁ -C ₆ alkylene group used in the present specification means a straight-chain or branched divalent hydrocarbon consisting of 1 to 6 carbon atoms, and includes, for example, methylene, ethylene, propylene, butylene, etc. It does not become.

The alkylene of C ₁ -C ₂₀ alkylene group, phenylene group, C ₃ -C ₁₀ cycloalkyl group, a C ₁ -C ₆ alkyl, C ₁ -C ₆ hydroxyalkyl group and a C ₁ -C ₆ of the group of One or more hydrogens are C ₁ -C ₆ alkyl group, C ₂ -C ₆ alkenyl group, C ₂ -C ₆ alkynyl group, C ₃ -C ₁₀ cycloalkyl group, C ₃ -C ₁₀ heterocyclo Alkyl group, C ₃ -C ₁₀ heterocycloalkyloxy group, C ₁ -C ₆ haloalkyl group, C ₁ -C ₆ alkoxy group, C ₁ -C ₆ thioalkoxy group, aryl group, acyl group, hydroxy , Thio, halogen, amino, alkoxycarbonyl, carboxy, carbamoyl, cyano, nitro, and the like.

In one embodiment of the present invention, R ¹ may be a C ₁ -C ₂₀ alkylene group, preferably a C ₁ -C ₁₂ alkylene group as described above. When R ¹ is a C ₁ -C ₂₀ alkylene group, the dispersibility of the scattering particles is excellent even without a solvent, so that the jetting property is improved, and the hardness and surface properties of the coating film may be improved.

In one embodiment of the present invention, m is an integer of 1 to 6, preferably an integer of 1 to 3, as described above. When m exceeds the above range, the jetting property may be poor due to an increase in viscosity.

In one embodiment of the present invention, p, q, r and n are integers of 0 to 5, preferably 0 to 3, as described above. When p, q, r, and n exceed the above range, the jetting property may be poor due to an increase in viscosity.

In one embodiment of the present invention, R ³ is hydrogen, methyl, ethyl, hydroxymethyl, a hydroxy group or a functional group represented by the following formula (3),

[Formula 3]

R ⁴ is hydrogen or a methyl group,

R ⁵ is an ethylene group,

L is absent or is a methylene group,

p, q, r and n are each independently an integer of 0 to 2,

t is 0 or 1.

The compound represented by Formula 1 serves to improve jetting properties by improving the dispersibility of scattering particles in the ink composition.

Specific examples of the compound represented by Formula 1 include 1,6-hexanediol diacrylate, 1,9-bisacryloyloxynonane, tripropylene glycol diacrylate, and the like.

When the compound represented by Formula 2 is used in a specific mixing ratio with the compound represented by Formula 1, it is possible to suppress the hardness of the coating film and the occurrence of wrinkles on the surface of the coating film.

Specific examples of the compound represented by Formula 2 include ethoxylated pentaerythritol tetraacrylate (EO 4 mol) (NK ESTER ATM-4E, Shinnakamura Chemical Co.), pentaerythritol triacrylate And a blend of pentaerythritol tetraacrylate (molar ratio, 0.6:0.4) (A-TMM-3LM-N, Shinnakamura Chemical Co., Ltd.), ethoxylated trimethylolpropane triacrylate (EO 3 mol) (A-TMPT-3EO , Shinnakamura Chemical Co.), ethoxylated glycerin triacrylate (EO 6mol) (A-GLY-6E, Shinnakamura Chemical Co., Ltd.), etc. are mentioned.

In one embodiment of the present invention, the mixing ratio of the compound represented by Formula 1 and the compound represented by Formula 2 is 40:60 to 80:20 by weight fraction. When the mixing ratio of the compound represented by Formula 1 and the compound represented by Formula 2 is within the above range, excellent coating film hardness can be ensured and wrinkles on the surface of the coating film can be suppressed. In the mixing ratio of the compound represented by Formula 1 and the compound represented by Formula 2, if the amount of the compound represented by Formula 1 is less than the above range, the dispersibility of the scattering particles may decrease, and the jetting property may be reduced. If it is more than the range, wrinkles may occur on the surface of the coating film.

The curable monomer (A) may be included in an amount of 50 to 95% by weight, preferably 60 to 95% by weight, based on 100% by weight of the total light scattering ink composition. If the content of the curable monomer is less than 60% by weight, the dispersibility of the scattering particles may be deteriorated, and if it exceeds 95% by weight, the scattering effect may be lowered.

Scattering particles (B)

In one embodiment of the present invention, the scattering particles serve to increase the overall light efficiency by increasing the path of light emitted from the blue light source.

As the scattering particles, conventional inorganic materials may be used, and metal oxides may be preferably used.

The metal oxides are Li, Be, B, Na, Mg, Al, Si, K, Ca, Sc, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, Rb, Sr, Y, Mo, Cs, Ba, La, Hf, W, Tl, Pb, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ti, Sb, Sn, Zr, Nb, It may be an oxide containing one metal selected from the group consisting of Ce, Ta, In, and combinations thereof, but is not limited thereto.

Specifically, Al ₂ O ₃ , SiO ₂ , ZnO, ZrO ₂ , BaTiO ₃ , TiO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , ITO, IZO, ATO, ZnO-Al, Nb ₂ O ₃ , SnO, MgO and One selected from the group consisting of a combination thereof is possible. If necessary, a material surface-treated with a compound having an unsaturated bond such as acrylate may also be used.

The scattering particles may have an average particle diameter of 30 to 1000 nm, preferably 100 to 500 nm, more preferably 150 to 300 nm. At this time, if the particle size is too small, a sufficient scattering effect of the light emitted from the quantum dots cannot be expected. On the contrary, if the particle size is too large, the surface of the light scattering layer of uniform quality or sink in the composition cannot be obtained, so it is appropriately adjusted within the above range. And use it.

The scattering particles may be included in an amount of 1 to 20% by weight based on 100% by weight of the total light scattering ink composition. If the content of the scattering particles is less than 1% by weight, the scattering effect may be reduced, and if it exceeds 20% by weight, the transmittance of the light-scattering layer may decrease.

Photopolymerization initiator (C)

The light scattering ink composition according to an embodiment of the present invention may further include a photoinitiator (C).

In one embodiment of the present invention, the photopolymerization initiator (C) may be used without particular limitation on its kind as long as it can polymerize the curable monomer. In particular, the photopolymerization initiator (C) is an acetophenone-based compound, a benzophenone-based compound, a triazine-based compound, a biimidazole-based compound, an oxime-based compound, and the like in terms of polymerization properties, initiation efficiency, absorption wavelength, availability, and price. It is preferable to use at least one compound selected from the group consisting of thioxanthone compounds.

Specific examples of the acetophenone-based compound include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 2-hydroxy-1-[4-(2-hydroxy) Oxyethoxy)phenyl]-2-methylpropan-1-one, 1-hydroxycyclohexylphenylketone, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 2-Benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propane-1 -One, 2-(4-methylbenzyl)-2-(dimethylamino)-1-(4-morpholinophenyl)butan-1-one, and the like.

Examples of the benzophenone-based compound include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenylsulfide, 3,3',4,4'-tetra( tert-butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzophenone, and the like.

Specific examples of the triazine-based compound include 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6 -(4-methoxynaphthyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-piperonyl-1,3,5-triazine, 2,4-bis (Trichloromethyl)-6-(4-methoxystyryl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(5-methylfuran-2- Yl)ethenyl]-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(furan-2-yl)ethenyl]-1,3,5-triazine , 2,4-bis(trichloromethyl)-6-[2-(4-diethylamino-2-methylphenyl)ethenyl]-1,3,5-triazine, 2,4-bis(trichloromethyl )-6-[2-(3,4-dimethoxyphenyl)ethenyl]-1,3,5-triazine, and the like.

Specific examples of the biimidazole-based compound include 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenylbiimidazole, 2,2'-bis(2,3- Dichlorophenyl)-4,4',5,5'-tetraphenylbiimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetra(alkoxyphenyl)biimi Dazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetra(trialkoxyphenyl)biimidazole, 2,2-bis(2,6-dichlorophenyl)-4 , 4',5,5'-tetraphenyl-1,2'-biimidazole or biimidazole compounds in which the phenyl group at the 4,4',5,5' position is substituted by a carboalkoxy group, and the like. have. Among these, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenylbiimidazole, 2,2'-bis(2,3-dichlorophenyl)-4,4' ,5,5'-tetraphenylbiimidazole, 2,2-bis(2,6-dichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole is preferably Used.

Specific examples of the oxime-based compound include o-ethoxycarbonyl-α-oxyimino-1-phenylpropan-1-one, and commercially available products include Irgacure OXE 01 and OXE 02 of BASF.

As the thioxanthone compound, for example, 2-isopropyl thioxanthone, 2,4-diethyl thioxanthone, 2,4-dichloro thioxanthone, 1-chloro-4-propoxy thioxanthone, etc. There is this.

The photopolymerization initiator (C) may be included in an amount of 2 to 20% by weight based on 100% by weight of the total light scattering ink composition. When the content of the photopolymerization initiator is less than 2% by weight, the hardness of the coating film may be lowered, and when it exceeds 20% by weight, yellowing may appear in the coating layer.

Additive (D)

In addition to the above components, the light scattering ink composition according to an embodiment of the present invention may further include additives such as surfactants and adhesion promoters in order to improve coating film flatness or adhesion.

When the light-scattering ink composition according to the present invention contains a surfactant, there is an advantage in that the flatness of the coating film can be improved. For example, the surfactants are BM-1000, BM-1100 (BM Chemie), Prolide FC-135/FC-170C/FC-430 (Sumitomo 3M), SH-28PA/-190/-8400/SZ-6032 A fluorine-based surfactant such as (Toray Silicone Co., Ltd.) may be used, but is not limited thereto.

The adhesion promoter may be added to increase adhesion to the substrate, and may include a silane coupling agent having a reactive substituent selected from the group consisting of a carboxyl group, a (meth)acryloyl group, an isocyanate group, an epoxy group, and combinations thereof. However, it is not limited thereto. For example, the silane coupling agent is trimethoxysilyl benzoic acid, γ-methacryloxypropyl trimethoxy silane, vinyltriacetoxysilane, vinyl trimethoxysilane, γ-isocyanate propyl triethoxysilane, γ-glycidoxy Propyl trimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and the like, and these may be used alone or in combination of two or more.

In addition to this, the light scattering ink composition according to the present invention may further include additives such as antioxidants, ultraviolet absorbers, and anti-aggregation agents within a range that does not impair the effects of the present invention, and the additives also do not impair the effects of the present invention. In the range, those skilled in the art can appropriately add and use.

The additive may be used in an amount of 0.05 to 10% by weight, specifically 0.1 to 10% by weight, and more specifically 0.1 to 5% by weight, based on 100% by weight of the total light scattering ink composition, but is not limited thereto.

The light-scattering ink composition according to an embodiment of the present invention has excellent dispersibility of scattering particles and can implement a low viscosity even though it is a solvent-free type that does not contain a solvent.

In addition, the light-scattering ink composition according to an embodiment of the present invention does not substantially contain a resin component, and even if it is included, it is contained within 0.5% by weight based on 100% by weight of the total light-scattering ink composition. Since the light scattering ink composition according to an embodiment of the present invention does not contain a resin component, a low viscosity can be realized, and thus nozzle jetting properties of the ink are excellent.

One embodiment of the present invention relates to a light-scattering pixel, that is, a transparent pixel, comprising a cured product of the light-scattering ink composition described above.

Further, an embodiment of the present invention relates to a color filter including the above-described light scattering pixels.

A method of forming a pattern of a light-scattering ink composition according to the present invention includes applying the above-described light-scattering ink composition to a predetermined area by an inkjet method and curing the applied light-scattering ink composition.

First, the light-scattering ink composition of the present invention is injected into an inkjet sprayer and printed on a predetermined area of a substrate.

The substrate is not limited, for example, a glass substrate, a silicon substrate, a polycarbonate substrate, a polyester substrate, an aromatic polyamide substrate, a polyamide-imide substrate, a polyimide substrate, an Al substrate, a substrate having a flat surface such as a GaAs substrate. I can. These substrates can be subjected to pretreatment such as chemical treatment with a chemical such as a silane coupling agent, plasma treatment, ion plating treatment, sputtering treatment, gas phase reaction treatment, and vacuum deposition treatment. When a silicon substrate or the like is used as the substrate, a charge coupled device (CCD), a thin film transistor (TFT), or the like may be formed on the surface of the silicon substrate or the like. Further, a partition wall matrix may be formed.

In order to form an appropriate phase on a substrate by spraying from a piezo inkjet head, which is an example of an inkjet sprayer, properties such as viscosity, fluidity, and scattering particles must be balanced with the inkjet head. The piezo inkjet head used in the present invention is not limited, but jets ink having a droplet size of about 10 to 100 pL, preferably about 20 to 40 pL.

The viscosity of the light scattering ink composition of the present invention is suitably about 3 to 30 cP, and more preferably is adjusted in the range of 7 to 20 cP.

The color filter according to an embodiment of the present invention includes a transparent pattern layer formed by the pattern forming method, that is, a transparent pixel layer. That is, the color filter is characterized in that it includes a transparent pixel layer formed by coating the above-described light-scattering ink composition on a substrate in a predetermined pattern and then curing it. Since the configuration and manufacturing method of the color filter are well known in the art, detailed descriptions are omitted.

An embodiment of the present invention relates to an image display device provided with the color filter described above.

The color filter of the present invention displays various images such as an electroluminescent display device (EL), a plasma display device (PDP), a field emission display device (FED), an organic light emitting device (OLED), as well as a general liquid crystal display device (LCD). Applicable to the device.

The image display device of the present invention includes a configuration known in the art, except for the color filter described above.

Hereinafter, the present invention will be described in more detail by Examples, Comparative Examples and Experimental Examples. These Examples, Comparative Examples and Experimental Examples are for illustrative purposes only, and it is obvious to those skilled in the art that the scope of the present invention is not limited thereto.

Preparation Example 1: Preparation of scattering particle dispersion (A1)

TiO ₂ (Ishihara Corporation CR-63) 70.0 parts by weight as scattering particles, 4.0 parts by weight of DISPERBYK-2001 (manufactured by BYK Corporation) as a dispersant, and 26 parts by weight of 1,6-hexanediol diacrylate as a solvent in a bead mill By mixing and dispersing for 12 hours, a scattering particle dispersion (A1) was prepared.

Examples and Comparative Examples: Preparation of light scattering ink composition

A light scattering ink composition was prepared by mixing each of the components in the composition of Table 1 below (% by weight).

Example Comparative example One 2 3 4 5 6 7 8 One 2 3 4 5 6 7 Scattering particles A1 8.4 8.4 8.4 8.4 8.4 8.4 8.4 8.4 8.4 8.4 8.4 8.4 8.4 8.4 8.4 Curable monomer B1 69.3 52.0 34.8 52.0 52.0 52.0 86.7 26.0 78.0 52.0 52.0 B2 52.0 B3 52.0 B4 17.4 34.7 51.9 34.7 34.7 86.7 60.7 8.7 34.7 B5 34.7 B6 34.7 B7 34.7 B8 34.7 B9 34.7 B10 52.0 Photopolymerization initiator C1 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 additive D1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1

A1: Scattering particle dispersion prepared in Preparation Example 1

B1: 1,6-hexanediol diacrylate (Sigma-Aldrich)

B2: 1,9-bisacryloyloxynonane (Ticia)

B3: Tripropylene glycol diacrylate (Sigma-Aldrich)

B4: Ethoxylated pentaerythritol tetraacrylate (EO 4 mol) (NK ESTER ATM-4E, Shinnakamura Chemical Co., Ltd.)

B5: Blend of pentaerythritol triacrylate and pentaerythritol tetraacrylate (molar ratio, 0.6:0.4) (A-TMM-3LM-N, Shinnakamura Chemical Co.)

B6: Ethoxylated trimethylolpropane triacrylate (EO 3 mol) (A-TMPT-3EO, Shinnakamura Chemical Co., Ltd.)

B7: Ethoxylated glycerin triacrylate (EO 6 mol) (A-GLY-6E, Shinnakamura Chemical Co., Ltd.)

B8: Blend of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (molar ratio, 1:1) (A-9550, Shinnakamura Chemical Co., Ltd.)

B9: isobornyl acrylate (Sigma-Aldrich)

B10: compound of formula a

[Formula a]

C1: Irgacure OXE-01 (BASF)

D1: SH8400 (Dow Corning Toray Silicon Inc.)

Experimental Example:

Using the light-scattering ink compositions prepared in the Examples and Comparative Examples, the following physical properties were evaluated in the following manner, and the results are shown in Table 2 below.

<Preparation of light scattering coating layer>

Each of the light-scattering ink compositions prepared in Examples and Comparative Examples was coated on a 5cm×5cm glass substrate by an inkjet method, and then, using a 1kW high-pressure mercury lamp containing all g, h, and i lines as an ultraviolet light source at 1000 mJ/cm 2 After irradiation, a light scattering coating layer was prepared by heating in a heating oven at 180° C. for 30 minutes.

(1) dispersibility

The light scattering ink composition was prepared, and a liquid sample was visually checked and evaluated according to the following evaluation criteria.

<Evaluation criteria>

○: No TiO ₂ particles are observed on the wall and bottom of the storage bottle

×: When it is confirmed that TiO ₂ particles are aggregated on the wall and bottom of the storage bottle

(2) Jetting

The jetting property of the ink was evaluated according to the following evaluation criteria using an inkjet drop analyzer.

<Evaluation criteria>

○: There is no clogging of the inkjet nozzle, and the direction of the jetted ink drop appears in a straight line.

×: clogging of the inkjet nozzle appears or the direction of the jetted ink drop does not appear in a straight line

(3) coating film hardness

The hardness characteristics of the coating film were confirmed by the pencil hardness after the thermal process (180°C/30 minutes). Pencil hardness was measured with a pencil hardness tester (Sukbo Science) according to JIS K 5400 and 5600 standards, and the pencil hardness range of 6B to 6H among the hardness guarantee pencils manufactured by Mitsubishi was used. First, pressing or scratching was observed with the naked eye, and it was determined as OK that pressing or scratching occurred less than 2 times out of 5 measurements. The coating film hardness was described as the maximum hardness determined as OK.

(4) Coating surface characteristics

The surface properties of the coating film were evaluated by the following evaluation criteria by observing the coating film surface with an optical microscope after the thermal process (180° C./30 minutes).

<Evaluation criteria>

○: No wrinkles occur on the surface of the coating film

×: wrinkles occur on the surface of the coating film

Dispersibility Jetting Film hardness Coating surface characteristics Example 1 ○ ○ 2H ○ Example 2 ○ ○ 2H ○ Example 3 ○ ○ 2H ○ Example 4 ○ ○ 2H ○ Example 5 ○ ○ 2H ○ Example 6 ○ ○ 2H ○ Example 7 ○ ○ 2H ○ Example 8 ○ ○ 2H ○ Comparative Example 1 ○ ○ 3B × Comparative Example 2 × × 3H × Comparative Example 3 × × 2H × Comparative Example 4 ○ ○ 3B × Comparative Example 5 × × 4H × Comparative Example 6 ○ ○ 5B × Comparative Example 7 × × 2H ○

As shown in Table 2, according to the present invention, the light scattering ink compositions of Examples 1 to 8 in which the compound represented by Formula 1 and the compound represented by Formula 2 were included in a specific mixing ratio as curable monomers had dispersibility of the scattering particles. It was excellent, and it was confirmed that the jetting property was improved, and the coating film hardness and the coating film surface characteristics were excellent. On the other hand, it was confirmed that the light scattering ink compositions of Comparative Examples 1 to 7 had poor dispersibility, jetting properties, coating hardness, and coating surface properties.

Specifically, Comparative Example 1 containing a compound represented by Formula 1 as a curable monomer but not including a compound represented by Formula 2 and a compound represented by Formula 1 exceeding the conditions of 40:60 to 80:20 The light-scattering ink composition of Example 4 has poor coating film hardness and coating surface properties, and contains a compound represented by Formula 2 as a curable monomer, but the compound represented by Comparative Example 2 and Formula 1 not including the compound represented by Formula 1 It was found that the light scattering ink composition of Comparative Example 3 contained less outside the condition of 40:60 to 80:20 had poor dispersibility, jetting properties, and coating surface properties. In addition, the light scattering ink composition of Comparative Example 5 containing a 5-functional or more curable monomer in place of the compound represented by Formula 2 had poor dispersibility, jetting properties, and coating surface properties, and instead of the compound represented by Formula 2 The light scattering ink composition of Comparative Example 6 containing the curable monomer was found to have poor coating film hardness and coating film surface properties. In addition, it was confirmed that the light scattering ink composition of Comparative Example 7 including the compound represented by Formula 1 having m exceeding 6 had poor dispersibility and jetting properties of the ink composition.

As described above, specific parts of the present invention have been described in detail, and it is obvious that these specific techniques are only preferred embodiments and are not intended to limit the scope of the present invention for those of ordinary skill in the art to which the present invention belongs. Do. Those of ordinary skill in the art to which the present invention belongs will be able to perform various applications and modifications within the scope of the present invention based on the above contents.

Therefore, it will be said that the substantial scope of the present invention is defined by the appended claims and their equivalents.

Claims (9)

A light scattering ink composition comprising a curable monomer and scattering particles,
The curable monomer includes a compound represented by the following Formula 1 and a compound represented by the following Formula 2,
A light scattering ink composition in which the mixing ratio of the compound represented by Formula 1 and the compound represented by Formula 2 is 40:60 to 80:20 by weight fraction:
[Formula 1]

[Formula 2]

In the above formula,
R ¹ is a C ₁ -C ₂₀ alkylene group,
R ² is hydrogen or a methyl group,
m is an integer from 1 to 6,
R ³ is hydrogen, a C ₁ -C ₆ alkyl group, a C ₁ -C ₆ hydroxyalkyl group, a hydroxy group, or a functional group represented by the following formula (3),
[Formula 3]

R ⁴ is hydrogen or a methyl group,
R ⁵ is a C ₁ -C ₂₀ alkylene group, a phenylene group or a C ₃ -C ₁₀ cycloalkylene group,
L is absent or a C ₁ -C ₆ alkylene group,
p, q, r and n are each independently an integer of 0 to 5,
t is 0 or 1. The light-scattering ink composition of claim 1, comprising the curable monomer in an amount of 50 to 95% by weight based on 100% by weight of the total light-scattering ink composition. The light scattering ink composition of claim 1, wherein the scattering particles include TiO ₂ . The light-scattering ink composition according to claim 1, wherein the scattering particles are included in an amount of 1 to 20% by weight based on 100% by weight of the total light-scattering ink composition. The light scattering ink composition according to claim 1, further comprising a photoinitiator. The light scattering ink composition according to claim 1, which does not contain a solvent. A light-scattering pixel comprising a cured product of the light-scattering ink composition according to any one of claims 1 to 6. A color filter including the light scattering pixel according to claim 7. An image display device comprising the curly filter according to claim 8.