KR101386207B1 - Pigment dispersion and process for preparing the same - Google Patents

Abstract

A pigment dispersion and a method for producing the same are provided.

The pigment dispersion may be a pigment surface-modified with a pigment derivative; Dispersing agent; And an organic solvent, wherein the organic solvent, the pigment derivative of Formula 1, and the pigment are mixed to form a mixture, and then the mixture is ground and dispersed in the presence of beads to modify the surface of the pigment, and the dispersant is added thereto. It is added, milled and dispersed in the presence of beads, and then filtered to prepare the pigment dispersion.

Description

Pigment dispersion and process for preparing the same {Pigment dispersion and process for preparing the same}

The present invention relates to a pigment dispersion and a method for producing the same, and more particularly, to a pigment dispersion with improved dispersion stability, storage stability, color characteristics and the like and a method for producing the same.

Color filters used in the manufacture of liquid crystal color displays, imaging devices, etc., spin coater pigment dispersions for color filters in which three pigments of red (R), green (G), and blue (B) are dispersed in the photosensitive resin liquid. It is manufactured by applying a method to form a colored film, and forming a desired pixel by exposure and development using a photomask on the colored film to pattern the colored film.

The characteristics required for the pigment dispersion for color filters require excellent optical properties such as high brightness, color power, and high contrast ratio, dispersibility, and storage stability. In order to prepare a pigment dispersion to satisfy these characteristics, fine pigment particles of 100 nm or less should be dispersed with a uniform distribution.

In order to obtain pigments suitable for pigment dispersions for color filters, a conventional technique is salt milling, in which salt particles are refined using salt, to prepare a pigment having a desired particle size and distribution. come.

The salt milling is a process of grinding a pigment using a kneader machine by mixing a medium capable of imparting a viscosity such as salt, pigment, and polyethylene glycol (DEG). Using this method has the advantage that the particle size of the pigment becomes fine and the distribution is improved to 20 nm to 100 nm or less, but a lot of contamination due to the consumption of a large amount of water used during the washing process after the pigment pulverization or the salt or DEG used Problems and economic problems will arise.

Therefore, there is a need for a pigment dispersion with improved dispersion stability and storage stability without using such a process and a method for producing the same.

The technical problem to be achieved by the present invention is to provide a pigment dispersion with improved dispersion stability and storage stability.

The technical problem to be achieved by the present invention is to provide a method for producing a pigment dispersion with improved economic efficiency without causing environmental pollution.

According to an aspect of the present invention,

A pigment surface-modified with a pigment derivative of Formula 1;

Dispersing agent; And

It provides a pigment dispersion comprising an organic solvent:

≪ Formula 1 >

Wherein X ₁ and X ₂ are each independently a single bond, —O—, —S—, —SO ₂ —, —CO—, —CH ₂ NHCOCH ₂ —, a substituted or unsubstituted C1-C30 alkylene group, Substituted or unsubstituted C1-C30 heteroalkylene group, substituted or unsubstituted C6-C30 arylene group, substituted or unsubstituted C6-C30 arylalkylene group, substituted or unsubstituted C2-C30 heteroarylene group , A substituted or unsubstituted C2-C30 heteroarylalkylene group, a substituted or unsubstituted C5-C20 cycloalkylene group, or a substituted or unsubstituted C2-C30 heterocycloalkylene group,

A represents N or a carbon atom having a substituent R ₁₀ ,

B represents O, a nitrogen atom having substituent R ₁₁ , or a carbon atom having substituents R ₁₂ and R ₁₃ ,

R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ , R ₉ , R ₁₀ , R ₁₁ , R ₁₂ and R ₁₃ are each independently hydrogen, halogen, nitro group, Substituted or unsubstituted amino group, cyano group, substituted or unsubstituted C1-C30 alkyl group, substituted or unsubstituted C1-C30 alkoxy group, substituted or unsubstituted C6-C30 aryl group, substituted or unsubstituted C6-C30 arylalkyl group, substituted or unsubstituted C6-C30 aryloxy group, substituted or unsubstituted C1-C30 heteroalkyl group, substituted or unsubstituted C1-C30 heteroalkoxy group, substituted or unsubstituted C2-C30 heteroaryl group, substituted or unsubstituted C2-C30 heteroarylalkyl group, substituted or unsubstituted C2-C30 heteroaryloxy group, substituted or unsubstituted C5-C20 cycloalkyl group, substituted or unsubstituted To a substituted C5-C30 heterocycloalkyl group, a substituted or unsubstituted C1-C30 alkyl ester group, a substituted or unsubstituted C1-C30 heteroalkyl It represents a hotel group, a substituted or unsubstituted C6-C30 aryl ester group of the ring, or a substituted or unsubstituted hetero-aryl ester of a C6-C30 ring,

n represents the integer of 1-3.

The present invention to achieve the above other technical problem,

Mixing an organic solvent, the pigment derivative of Formula 1 and the pigment to form a mixture;

Grinding and dispersing the mixture in the presence of beads to modify the surface of the pigment;

It provides a method for producing a pigment dispersion comprising the step of adding a dispersant to the surface-modified pigment, milled and dispersed in the presence of beads, and then filtration.

According to one embodiment of the present invention, as the pigment derivative of Chemical Formula 1, a pigment derivative of Chemical Formula 2 to 4 is preferable:

(2)

(3)

≪ Formula 4 >

In the formula,

X ₁ represents a single bond, -SO _2- , -CO-, -CH ₂ NHCOCH _2- , or -CH _2- ,

n represents an integer of 1 to 10;

According to one embodiment of the invention, the pigment dispersion comprises 100 parts by weight of the pigment, 0.01 to 50 parts by weight of the pigment derivative, 1 to 30 parts by weight of the dispersant, and 100 to 1,000 parts by weight of the organic solvent.

According to an embodiment of the present invention, the organic pigment in the compound of Formula 1 has a bondable site of 1 to 3, diketopyrrolopyrrole pigments, azo pigments, phthalocyanine pigments, anthraquinone pigments, Quinacridone pigments, dioxazine pigments, perinone pigments, perylene pigments, thioindigo pigments, isoindolin pigments, isoindolinone pigments, quinophthalone pigments, srenne pigments or metal complex pigments desirable.

According to one embodiment of the present invention, red pigments, blue pigments, green pigments, yellow pigments or purple pigments may be used as the pigments.

According to one embodiment of the invention, the dispersant is preferably a high molecular weight dispersant having a weight average molecular weight of 1,000 to 100,000.

According to one embodiment of the invention, the dispersant may further comprise a resinous dispersant.

According to one embodiment of the present invention, the organic solvent is preferably a solvent selected from esters of 3 to 12 carbon atoms, ketones, ethers, alcohols, hydrocarbons and the like.

According to one embodiment of the invention, the pigment dispersion is suitable for the production of color filters.

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

The pigment dispersion according to the present invention improves dispersion stability, storage stability and color characteristics by using a pigment refined by surface modification together with a pigment derivative of a specific structure, and in particular, the method of preparing the pigment dispersion according to the present invention is a washing process. Omitting reduces environmental pollution and increases economic efficiency.

Pigment dispersion according to the present invention, the pigment surface-modified with a pigment derivative of formula (1); Dispersing agent; And an organic solvent; provides a pigment dispersion comprising:

≪ Formula 1 >

Wherein X ₁ and X ₂ are each independently a single bond, —O—, —S—, —SO ₂ —, —CO—, —CH ₂ NHCOCH ₂ —, a substituted or unsubstituted C1-C30 alkylene group, Substituted or unsubstituted C1-C30 heteroalkylene group, substituted or unsubstituted C6-C30 arylene group, substituted or unsubstituted C6-C30 arylalkylene group, substituted or unsubstituted C2-C30 heteroarylene group , A substituted or unsubstituted C2-C30 heteroarylalkylene group, a substituted or unsubstituted C5-C20 cycloalkylene group, or a substituted or unsubstituted C2-C30 heterocycloalkylene group,

A represents N or a carbon atom having a substituent R ₁₀ ,

B represents O, a nitrogen atom having substituent R ₁₁ , or a carbon atom having substituents R ₁₂ and R ₁₃ ,

R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ , R ₉ , R ₁₀ , R ₁₁ , R ₁₂ and R ₁₃ are each independently hydrogen, halogen, nitro group, Substituted or unsubstituted amino group, cyano group, substituted or unsubstituted C1-C30 alkyl group, substituted or unsubstituted C1-C30 alkoxy group, substituted or unsubstituted C6-C30 aryl group, substituted or unsubstituted C6 -C30 arylalkyl group, substituted or unsubstituted C6-C30 aryloxy group, substituted or unsubstituted C1-C30 heteroalkyl group, substituted or unsubstituted C1-C30 heteroalkoxy group, substituted or unsubstituted C2 -C30 heteroaryl group, substituted or unsubstituted C2-C30 heteroarylalkyl group, substituted or unsubstituted C2-C30 heteroaryloxy group, substituted or unsubstituted C5-C20 cycloalkyl group, substituted or unsubstituted Substituted C5-C30 heterocycloalkyl group, substituted or unsubstituted C1-C30 alkyl ester group, substituted or unsubstituted C1-C30 heteroalkyl group It represents a hotel group, a substituted or unsubstituted C6-C30 aryl ester group of the ring, or a substituted or unsubstituted hetero-aryl ester of a C6-C30 ring,

n represents the integer of 1-3.

As the pigment derivative of Formula 1, compounds of the following Formulas 2 to 4 are preferred:

(2)

(3)

≪ Formula 4 >

In the formula,

X ₁ represents a single bond, -SO _2- , -CO-, -CH ₂ NHCOCH _2- , or -CH _2- ,

n represents an integer of 1 to 10;

In the above formula, X ₁ is preferably a single bond or -SO _2- , and n is preferably an integer of 1 to 3.

Pigment derivatives having the structure of Formula 1, preferably Formula 2 to 4 are used to modify the surface of the pigment, improve the dispersion stability and storage stability of the pigment, and serves to improve the color characteristics .

The pigment derivative is obtained by introducing a reactive substituent to an organic pigment that is generally used, and then reacting the amine derivative thereto to obtain a pigment derivative having the structure of Chemical Formula 1.

Although it does not specifically limit as an organic pigment which can form the said pigment derivative, Azo pigments, such as a diketopyrrolopyrrole pigment, azo, disazo, and poly azo, a phthalocyanine pigment, diamino dianthraquinone, anthrapyri Anthraquinone pigments such as midine, flavantron, anthrone, indanthrone, pyrantrone, and violatron, quinacridone pigments, dioxazine pigments, perinone pigments, perylene pigments, thioindigo pigments, isoindoline Examples thereof include a pigment, an isoindolinone pigment, a quinophthalone pigment, a styrene pigment and a metal complex pigment.

Reactive substituents introduced into such organic pigments preferably include substituents that can easily react with amines, such as halides, for example -SO ₂ Cl, -COCl, -CH ₂ NHCOCH ₂ Cl or- CH ₂ Cl and the like. Such reactive substituents may be substituted with one to three organic pigments, and may be introduced differently depending on the purpose. Preferably one reactive substituent may be introduced.

The reactive substituent is combined with the amine component having various structures to form the pigment derivative of Chemical Formula 1.

Such pigment derivative may be used in an amount of 0.01 to 50 parts by weight, preferably 1 to 20 parts by weight, based on 100 parts by weight of the pigment, and sufficient surface modification to the pigment when the content of the pigment derivative is less than 0.01 part by weight. It is difficult to carry out the treatment, and when it exceeds 50 parts by weight, there is a problem such as a decrease in luminance or heat resistance, which is not preferable.

The pigment to modify the surface with the pigment derivative may be used without limitation any pigments commonly used in the field of the display device, and may use one or more of red pigment, blue pigment, green pigment, yellow pigment or purple pigment. In particular, the pigment which is not surface-treated is more preferable.

C.I. Pigment Red 7, 14, 48: 1, 48: 2, 48: 3, 48: 4, 81: 1, 81: 2, 81: 3, 146, 177, 184, 185, 187, 200, 202, 208, 210, 246, 254, 255, 264, 270, 272, etc. may be used, and in the case of the green pigment CI Pigment Green 7, 10, 36, 37, such as green pigments can be used, and in the case of the blue pigment C.I. Pigment Blue 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 80 and the like can be used, and the yellow pigment, C.I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 24, 31, 32, 34, 35, 35: 1, 36, 36: 1, 37, 37: 1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 126, 127, 128, 129, 138, 139, 147, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 185, 187, 188, 193, 194, 199, 213, 214 and the like can be used, and in the case of the purple pigment CI Pigment Violet 23, 34, 35, 37, etc. can be used, These can be used individually or in mixture of 2 or more types.

The pigment described above is modified on the surface of the pigment derivative, which means that the pigment derivative is bonded on the surface of the pigment through a grinding and dispersing process such as milling, etc., thereby improving the properties of the pigment. It becomes possible. In other words, the pigment derivative forms a homogeneous coating layer on the surface of the pigment, which means a continuous or discontinuous coating layer. Through the surface layer of such a pigment derivative, it becomes possible to improve the dispersion stability, storage stability and color characteristics of the pigment.

The pigment derivative and the pigment do not necessarily need to be combined with ones showing the same color, and it is also possible to use materials showing different colors as necessary. In other words, it is possible to produce a pigment exhibiting a complex color by modifying the surface with a yellow pigment derivative to a yellow pigment, and it is also possible to improve color purity by using a pigment and a pigment derivative having the same color.

The organic solvent used in the pigment dispersion is not particularly limited as long as it can disperse the pigment and the like, and a solvent selected from esters of 3 to 12 carbon atoms, ketones, ethers, alcohols, hydrocarbons and the like is preferable. The ester, ketone, ether or alcohol may have a ring structure. Compounds having two or more functional groups (-O-, -CO- and -COO-) such as esters, ketones and ethers may also be used as the solvent, and other functional groups such as alcoholic hydroxy may be present at the same time. In the case of a solvent having two or more functional groups, many carbon atoms may be present within the range defined for the compound having the functional group.

Examples of the ester having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate or pentyl acetate.

Examples of the ketone having 3 to 12 carbon atoms include acetone, methyl isobutyl ketone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone and methylcyclohexanone.

Examples of the ether having 3 to 12 carbon atoms include propylene glycol monomethyl ether acetate, diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxane, tetrahydrofuran, and Examples are sol and phenitol.

Moreover, 2-ethoxyhexyl acetate, 2-methoxyethanol, and 2-butoxyethanol are mentioned as an organic solvent which has 2 or more types of functional groups.

Alcohols usable in combination with the chlorinated organic solvents are also linear, branched or cyclic, of which saturated aliphatic hydrocarbons are preferred. The hydroxy group of the alcohol may be monovalent, divalent or trivalent. Examples of the alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol, 2-methyl-2butanol, and cyclohexanol. Examples of the fluorinated alcohols include 2-fluoroethanol, 2,2,2-trifluoroethanol or 2,2,3,3-tetrafluoro-1-propanol.

In addition, the hydrocarbon may be linear, branched or cyclic, and an aromatic hydrocarbon or an aliphatic hydrocarbon may be used. Aliphatic hydrocarbons can be used both saturated and unsaturated. Examples of such hydrocarbons include cyclohexane, hexane, benzene, ethylbenzene, toluene and xylene.

Such an organic solvent may be used in an amount capable of dispersing the pigment particles in the pigment dispersion, and there is no particular limitation, but may be used in an amount of 100 to 1,000 parts by weight based on 100 parts by weight of the pigment. If the content of the organic solvent is less than 100 parts by weight, sufficient pigment dispersion cannot be obtained, the viscosity is high, and workability is lowered. If the content is more than 1,000 parts by weight, the pigment concentration is too low, making it difficult to sufficiently express a desired color. have.

In order to disperse | distribute the said pigment etc. in the said organic solvent, it is preferable to use a dispersing agent, and it is preferable to use a high molecular weight dispersing agent as such a dispersing agent.

As the high molecular weight dispersant, preferably those having a weight average molecular weight in the range of 1,000 to 100,000 can be used, and more preferably, a high molecular weight dispersant having a weight average molecular weight of 10,000 to 30,000 is used. As such a high molecular weight dispersant, commercially available products such as trade names EFKA4046 (manufactured by EFKA), PB-821 (manufactured by Ajinomoto Fine Techno), and SP24000 (manufactured by Avecia) can be used.

Such a high molecular weight dispersant may be used in an amount of 1 to 30 parts by weight based on 100 parts by weight of the pigment. If the content of the dispersant is less than 1 part by weight, a sufficient dispersing effect may not be obtained. Not preferred.

The dispersant may further contain a resinous dispersant in addition to the high molecular weight dispersant, wherein the resinous dispersant comprises a pigment affinity site having a property of adsorbing to the pigment, and a site compatible with the pigment carrier. Adsorption to stabilize the dispersion of the pigment into the pigment carrier.

As such a resin type dispersing agent, Polycarboxylic acid esters, such as polyurethane and polyacrylate, unsaturated polyamide, polycarboxylic acid, polycarboxylic acid amine salt, polycarboxylic acid ammonium salt, polycarboxylic acid alkyl amine Salts, polysiloxanes, long chain polyamino amide phosphates, hydroxyl group-containing polycarboxylic acid esters or modified products thereof, (meth) acrylic acid-styrene copolymers, (meth) acrylic acid- (meth) acrylic acid ester copolymers, styrene-maleic acid Copolymer, polyvinyl alcohol, polyester type, modified polyacrylate type, etc. can be used, These can be used individually or in mixture of 2 or more types.

Such a resinous dispersant may be used in an amount of 1 to 30 parts by weight based on 100 parts by weight of the pigment.

The pigment dispersion having the composition as described above may be usefully used in various display devices, and is particularly useful for producing color filters.

The pigment dispersion according to the present invention as described above can be prepared as follows.

Method for producing a pigment dispersion according to the present invention comprises the steps of (a) mixing an organic solvent, the pigment derivative of Formula 1 and the pigment to form a mixture; (b) grinding and dispersing the mixture in the presence of beads to modify the surface of the pigment; (c) adding a dispersant to the surface modified pigment, grinding and dispersing in the presence of beads, and then filtering.

For the pigment derivative, the pigment, the dispersant, the organic solvent, and the like of Formula 1, the kind and content as described above may be used.

In the manufacturing method according to the present invention, using the beads as the dispersion medium has the advantage that can be removed by a simple filtration process without the need for a water washing process can reduce a lot of time and economic losses required for the water washing process. As such a dispersion medium, glass beads, ball beads, zirconium beads, or the like can be used. It is preferable to use such beads having a particle diameter of 0.1 to 1.2 mm.

The surface modification of the pigment using the pigment derivative may be performed by adding a pigment and a pigment derivative to an organic solvent and mixing the mixture, and then uniformly using a dispersion machine such as a horizontal medium dispersion machine, a vertical medium dispersion machine, a pin mill, or a ball mill. After mixing and grinding, the organic solvent can be evaporated to obtain a surface modified pigment having properties suitable for pigment dispersions, in particular pigment dispersions for color filters.

In the surface modification step or the dispersion forming step, the grinding time is suitably about 2 hours to 24 hours, and may proceed further. In addition, the rotation speed of the grinder is suitably about 1000rpm to 6000rpm, preferably from 2000rpm to 4000rpm. Pigment surface modification process is preferably performed in the chamber temperature range of 30 ℃ to 200 ℃, the suitable temperature may vary depending on the type of pigments and pigment derivatives applied.

On the other hand, the process of (b) and (c) may proceed sequentially, but after mixing all the components, it is also possible to proceed with the process of (b) and (c) at the same time.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1

-Synthesis of Blue Pigment Derivatives

45 g of CI Pigment Blue 15: 6 (BASF Co., Ltd .: Heliogen Blue L6700F) was added to 450 g of fuming sulfuric acid (20% SO ₃ ) with stirring, followed by sulfonation by stirring at 30 ° C. for 3 hours. The reaction solution was poured into 5000 g of ice water with slow stirring, and the precipitate was filtered to obtain a paste of sulfonated phthalocyanine pigment. The aqueous paste was reslurried in 5000 g of water, 30 g of morpholinopropyl amine was added thereto, stirred at 50 ° C. for 1 hour, and the sulfonamide-reacted paste of the phthalocyanine pigment obtained by filtering the precipitate was dried to give a basic solution. A blue pigment derivative was obtained.

-Pigment surface treatment using beads

500 g of propylene glycol monomethyl ether acetate, 10 g of the above-mentioned blue pigment derivative and 50 g of a blue pigment (PB 15: 6, manufactured by BASF) were mixed in a 1 L container, filled with 0.6 mm zirconium beads, and the basket mill was It was dispersed for 8 hours at 80 ℃.

After the dispersion was completed, the surface-treated pigment dispersion was filtered through filter paper and dried in an oven at 100 ° C. for 1 day. The particle size of the pigment particles during dispersion was analyzed by an electron transmission microscope (TEM) to obtain a surface modified pigment having a primary particle of 50nm.

-Preparation of pigment dispersion for color filter

20 parts by weight of the surface-treated pigment dried using beads, 1.5 parts by weight of pigment derivative of formula (2), 6 parts by weight of EFKA 4046 (high molecular weight dispersant from EFKA, Germany), 5 parts by weight of acrylic resin, propylene glycol monomethyl ether acetate After mixing 67.5 parts by weight, using a 0.3 mm diameter zirconium beads, dispersed for 3 hours with an Eiger mill, and then filtered with a filter of 5㎛ to prepare a pigment dispersion according to the present invention.

Examples 2 to 10 and Comparative Examples 1 to 10

The mixing ratios of the compositions of Examples 2 to 10 and Comparative Examples 1 to 10 were the same, and Examples 1 to 10 used surface-treated pigments in order to confirm the properties of the surface-treated pigments and general pigments, and Comparative Examples 1 to 10. 10 was dispersed using a general pigment. Blue pigment is Heliogen Blue L6700F, manufactured by BASF, and Heliogen Green K9360, manufactured by BASF. After uniformly mixing the mixture of the composition shown in Table 1, using 0.3 mm zirconium beads, it disperse | distributed with Eiger mill for 3 hours, and filtered with the filter of 5 micrometers, and produced the pigment dispersion which concerns on this invention.

In addition, the preparation of the compounds of Formula 3 and Formula 4, which are pigment derivatives used in Examples and Comparative Examples, are as follows.

-Formula 3

45 g of CI Pigment Blue 15: 6 (BASF Co., Ltd .: Heliogen Blue L6700F) was added to 450 g of fuming sulfuric acid (20% SO ₃ ) with stirring, followed by sulfonation by stirring at 30 ° C. for 3 hours. The reaction solution was poured into 5000 g of ice water with slow stirring, and the precipitate was filtered to obtain a paste of sulfonated phthalocyanine pigment. The aqueous paste was reslurried in 5000 g of water, and 30 g of 1-Piperidinecarboxamide was added thereto, stirred at 50 ° C. for 1 hour, and the sulfonamide-reacted paste of the phthalocyanine pigment obtained by filtering the precipitate was dried to obtain a basic blue pigment derivative. .

-Formula 4

45 g of CI Pigment Blue 15: 6 (BASF Co., Ltd .: Heliogen Blue L6700F) was added to 450 g of fuming sulfuric acid (20% SO ₃ ) with stirring, followed by sulfonation by stirring at 30 ° C. for 3 hours. The reaction solution was poured into 5000 g of ice water with slow stirring, and the precipitate was filtered to obtain a paste of sulfonated phthalocyanine pigment. The aqueous paste was reslurried in 5000 g of water, 30 g of 4-Piperidinecarboxamide was added and stirred at 50 ° C. for 1 hour, and then the precipitate was filtered to dry the sulfonamide-reacted paste of the obtained phthalocyanine pigment to obtain a basic blue pigment derivative. .

division Compounding amount (unit: parts by weight) Pigment Pigment derivative High molecular weight dispersant Acrylic resin solvent Kinds content Kinds content Kinds content content content Example 1 Blue pigment
(Surface treatment) 20 (2) 1.5 EFKA4046 6.0 5.0 67.5 Example 2 25 (3) 1.0 EFKA4046 6.0 5.0 63 Example 3 25 Formula 4 1.0 EFKA4046 6.0 5.0 63 Example 4 20 (2) 1.5 PB-821 6.0 5.0 67.5 Example 5 20 (2) 0.5 PB-821 6.0 5.0 68.5 Comparative Example 1 Blue pigment
(Heliogen
Blue
L6700F) 20 (2) 1.5 EFKA4046 6.0 5.0 67.5 Comparative Example 2 25 (3) 1.0 EFKA4046 6.0 5.0 63 Comparative Example 3 25 Formula 4 1.0 EFKA4046 6.0 5.0 63 Comparative Example 4 20 (2) 1.5 PB-821 6.0 5.0 67.5 Comparative Example 5 20 (2) 0.5 PB-821 6.0 5.0 68.5 Example 6 Green pigment
(Surface treatment) 20 (2) 1.5 SP24000 6.0 5.0 67.5 Example 7 20 (3) 2.0 SP24000 6.0 5.0 67 Example 8 25 (2) 1.5 PB-821 6.0 5.0 62.5 Example 9 20 (2) 1.5 PB-821 6.0 5.0 67.5 Example 10 20 Formula 4 1.0 PB-821 6.0 5.0 68 Comparative Example 6 Green pigment
(Heliogen
Green
K9360) 20 (2) 1.5 SP24000 6.0 5.0 67.5 Comparative Example 7 20 (3) 2.0 SP24000 6.0 5.0 67 Comparative Example 8 25 (2) 1.5 PB-821 6.0 5.0 62.5 Comparative Example 9 20 (2) 1.5 PB-821 6.0 5.0 67.5 Comparative Example 10 20 Formula 4 1.0 PB-821 6.0 5.0 68

In Table 1, blue pigment C.I. Pigment Blue 15: 6 is BASF product "Heliogen Blue L6700F", and green pigment C.I.Pigment Green 36 represents BASF product "Heliogen Green K9360". The high molecular weight dispersant EFKA4046 is manufactured by EFKA, PB-821 is "Ajisper PB-821" manufactured by Ajinomoto Fine Techno, and SP24000 represents "Solsperse 24000" manufactured by AVECIA. The acrylic resin has a molecular weight of 15,000 and an acid value of 100. The solvent used propylene glycol monomethyl ether acetate.

The pigment dispersions obtained in Examples 1 to 10 and Comparative Examples 1 to 10 were equipped with particle size, viscometer, colorimeter, and luminance meter equipment to evaluate the properties of each pigment dispersion and the results are shown in Table 2 below.

division evaluation Viscosity Mouth dildo Storage stability Developability Contrast ratio Example 1 7.8 62 ◎ ○ ◎ Example 2 6.5 61.2 ○ ○ ◎ Example 3 7.2 67 ◎ ◎ ◎ Example 4 7.9 63.7 ○ △ ○ Example 5 5.5 66.0 ◎ ○ ◎ Comparative Example 1 13.4 74.5 ○ ○ △ Comparative Example 2 12.9 72.1 △ ○ ○ Comparative Example 3 16.0 78.0 ○ X X Comparative Example 4 11.3 74.0 X △ X Comparative Example 5 12.5 81.0 △ X X Example 6 5.6 52.0 ◎ ◎ ○ Example 7 5.9 51.9 ◎ ◎ ○ Example 8 4.2 61.3 △ ○ ◎ Example 9 6.3 60.0 ○ ○ ◎ Example 10 6.5 54.2 ◎ ○ ○ Comparative Example 6 9.5 80.3 X △ △ Comparative Example 7 9.3 79.8 ○ X X Comparative Example 8 11.1 76.5 X △ X Comparative Example 9 10.9 77.6 X △ △ Comparative Example 10 10.3 81.0 ○ ○ △

(◎: very good, ○: excellent, △: normal, X: bad)

As the analytical equipment used for the analysis of the above examples and comparative examples, a viscometer: "DV-III ULTRA" manufactured by Brookfield, a particle size meter: "ELS-ZETA" manufactured by Otsuka, and a luminance meter "LS-100" manufactured by Minolta were used.

As shown in Table 2, the pigment dispersion of the present invention is excellent in dispersion stability, storage stability, it can be seen that the contrast ratio is particularly excellent.

The pigment dispersion according to the present invention is characterized by excellent dispersion stability of the pigment, particularly high contrast ratio, by using a pigment and a basic pigment derivative, which have been refined by the pigment surface treatment. In addition, the method of preparing the pigment dispersion is that by replacing the dispersion medium from the salt to the bead can be filtered, thereby eliminating the washing process for removing the salt it is possible to reduce a lot of time and economic losses in the washing process.

Claims (11)

delete A pigment surface-modified with a pigment derivative represented by any one of the following Chemical Formulas 2 to 4; Dispersing agent; And Pigment dispersion comprising an organic solvent; (2)

(3)

≪ Formula 4 >

In the formula, X ₁ represents a single bond, -SO _2- , -CO-, -CH ₂ NHCOCH _2- , or -CH _2- , n represents an integer of 1 to 10; The pigment dispersion according to claim 2, wherein the pigment dispersion comprises 100 parts by weight of the pigment, 0.01 to 50 parts by weight of the pigment derivative, 1 to 30 parts by weight of the dispersant, and 100 to 1,000 parts by weight of the organic solvent. The method of claim 2, wherein the organic pigment of the compound represented by any one of Formulas 2 to 4 has a bondable position of 1 to 3, diketopyrrolopyrrole pigments, azo pigments, phthalocyanine pigments, anthraqui Non-based pigments, quinacridone pigments, dioxazine pigments, perinone pigments, perylene pigments, thioindigo pigments, isoindolin pigments, isoindolinone pigments, quinophthalone pigments, styrene pigments or metal complexes Pigment dispersion characterized by the above-mentioned. The pigment dispersion according to claim 2, wherein the pigment is a red pigment, a blue pigment, a green pigment, a yellow pigment or a purple pigment. The pigment dispersion according to claim 2, wherein the dispersant is a high molecular weight dispersant having a weight average molecular weight of 1,000 to 100,000. 7. The pigment dispersion according to claim 6, wherein the dispersant further comprises a resinous dispersant. The pigment dispersion according to claim 2, wherein the organic solvent is an ester, ketone, ether, alcohol or hydrocarbon having 3 to 12 carbon atoms. The pigment dispersion according to claim 2, wherein the pigment dispersion is for producing a color filter. (a) mixing an organic solvent, a pigment derivative represented by any one of Formulas 2 to 4, and a pigment to form a mixture; (b) grinding and dispersing the mixture in the presence of beads to modify the surface of the pigment; And (c) adding a dispersant to the surface-modified pigment, pulverizing and dispersing in the presence of beads, and then filtering. (2)

(3)

≪ Formula 4 >

In the formula, X ₁ represents a single bond, -SO _2- , -CO-, -CH ₂ NHCOCH _2- , or -CH _2- , n represents an integer of 1 to 10; The method of claim 10, wherein the steps (b) and (c) are carried out sequentially or simultaneously.