KR20070072281A - An aqueous tinter composition - Google Patents

Abstract

Provided are an aqueous toner composition which shows a satisfactory compatibility in case of the application to an aqueous paint, is free from the deterioration of fluidity even if used with another toner, and is stable to color separation, and a paint containing the composition. The aqueous toner composition comprises: 5-10 parts by weight of a polyurethane water-dispersible resin having an anionic functional group; 15-25 parts by weight of a polyurethane-acrylic water-dispersible resin; 10-20 parts by weight of an aqueous dispersant; 2-6 parts by weight of a solvent; 0.5-2.0 parts by weight of a wetting agent; 30-40 parts by weight of a pigment; and 2-8 parts by weight of a neutralizer. Preferably the polyurethane water-dispersible resin is neutralized with a tertiary amine and has a degree of neutralization of 40-90 %.

Description

Aqueous colorant composition {AN AQUEOUS TINTER COMPOSITION}

 The present invention relates to an aqueous colorant composition, and more particularly to an aqueous colorant composition comprising a polyurethane water dispersion resin and a polyurethane-acrylic water dispersion resin.

Conventional aqueous colorants have generally been used for dispersion and storage stability in addition to aqueous dispersants, polyester or polyurethane water dispersion resins, which are resins for dispersion. In addition, in order to save energy and maximize the efficiency of the process by shortening the process, the colorant needs to be gradually converted to high concentration and high saturation, and high pigment content and high dispersion in the colorant are required for the high concentration and high saturation colorant. . However, as a result, problems of color change due to fluidity deterioration, color separation, sedimentation, shelf life, and water deposition of the colorant have occurred.

In recent years, the technological trend of automotive paints in the world has been focused on water-based development, and developments are under way to obtain visible effects such as energy saving, production equipment and operation cost reduction, labor cost reduction, and labor cost reduction. In particular, the movement to reduce volatile organic compounds is becoming active, and a series of responses to organic solvents are approaching realities in automobile companies, and inevitably, the adoption of volatile organic compound reduction technology is expected to proceed in Korea. It is expected. In addition, although the technology of water-based automotive paints has been developed, it is a time when high-concentration and high-saturation water-based colorant technology is required.

The object of the present invention is good compatibility with water-based paints, there is no fluidity deterioration even when using a large amount of colorant, excellent color separation, long-term storage at room temperature and heat storage, stable to sedimentation, color discoloration by water To provide little water-based colorant composition.

The present invention is 5 to 10 parts by weight of polyurethane water-dispersion resin having an anion functional group, 15 to 25 parts by weight of polyurethane-acrylic water dispersion resin, 10 to 20 parts by weight of aqueous dispersant, 2 to 6 parts by weight of solvent, 0.5 to wetting agent It relates to an aqueous colorant composition comprising 2.0 parts by weight, 30 to 40 parts by weight of pigment and 0.2 to 0.8 parts by weight of neutralizing agent.

Hereinafter, the present invention will be described in detail.

The polyurethane water dispersion resin according to the present invention is prepared by polymerizing a polyol, an excess of isocyanate, and a compound having an anionic functional group to form a polyurethane resin, neutralizing the anionic functional group in the polyurethane with an appropriate base, and then dispersing it in water. do.

The polyols used in the preparation of the polyurethane water-dispersible resins can be freely selected from known polyols generally used in preparing polyurethanes as long as they do not adversely affect the compatibility and flowability of the aqueous colorant composition. Polyols include, but are not limited to, for example, polyether polyols, polyester polyols, polycarbonate polyols, and poly caprolactone polyols.

The isocyanate used in the preparation of the polyurethane water dispersion resin can be freely selected from known isocyanates which are generally used for preparing polyurethanes as long as they do not adversely affect the physical properties of the water-based colorant composition. Isocyanates include, but are not limited to, toluene diisocyanate, 4,4'-hexaphenyl phenyl methane diisocyanate, 4,4'-dicyclo hexyl methane diisocyanate, 1,6-hexamethylene diisocyanate and isophorone At least one selected from the group consisting of diisocyanates.

Compounds that can be used to provide anionic functionality to the polyurethane are compounds having at least two hydroxyl groups and a carboxyl or sulfone group. Preferably, the carboxyl group is suitable for the present invention because it has good water resistance and excellent dispersibility. Compounds having an anionic functional group that can be used in the present invention may be used, for example, but not limited to dimethylol propionic acid (DMPA) or dimethylol butanoic acid (DMBA).

The compounds having polyol, isocyanate and anionic functional groups used to polymerize the polyurethane resin according to the present invention are used in an amount of 10 to 40 parts by weight, 10 to 40 parts by weight, and 5 to 20 parts by weight, respectively. If the polyol is less than 10 parts by weight, the synthesis is unstable, and if it is more than 40 parts by weight, the coating film is not firm. If the isocyanate is less than 10 parts by weight, the coating film is not firm. If it is more than 40 parts by weight, the synthesis is unstable. If the compound having an anionic functional group is less than 5 parts by weight, the resin dispersibility is unstable, and if it exceeds 20 parts by weight, the water resistance is weak.

The polyurethane resin formed by polymerization of a polyol, excess isocyanate, and a compound having an anionic functional group is neutralized using a tertiary amine. Preferred tertiary amines include triethylamine, dimethylethanolamine and the like. The degree of neutralization of the anion functional group inside the polyurethane is 40 to 90%, preferably 50 to 90%. If it is less than 40%, water dispersion is unstable, and if it exceeds 90%, the water resistance of a coating film is weak. Water is added to the neutralized polyurethane resin to disperse the water. The water dispersion is preferably carried out at 40 ° C. or lower to suppress side reactions with isocyanates.

The weight average molecular weight of the polyurethane water dispersion resin according to the present invention is 5,000 to 50,000, preferably 10,000 to 40,000, most preferably 20,000 to 30,000. If the weight average molecular weight is less than 5,000, the coating film properties are lowered. If the weight average molecular weight is more than 50,000, the storage property is lowered. The content of the polyurethane water dispersion resin in the water-based colorant composition according to the present invention is 5 to 10 parts by weight, preferably 6 to 8 parts by weight, based on the total amount of the water-based colorant composition. If the content of the polyurethane water dispersion resin is less than 5 parts by weight, the wettability of the pigment becomes weak, the impact after the coating film is lowered, the workability is not good. Moreover, when it exceeds 10 weight part, a viscosity raises severely and a problem arises in flowability.

The solid amount of the polyurethane water dispersion resin used in the colorant is 0.3 to 0.5 times, and most preferably 0.35 to 0.45 as compared to the polyurethane-acrylic water dispersion resin solid content according to the present invention described below. If it is less than 0.3 times, the wettability of the pigment is insufficient, and if it is more than 0.5 times, a lot of bubbles are generated during dispersion, and the price of raw material costs increases.

The polyurethane-acrylic water-dispersion resin according to the present invention is prepared by reacting a polyurethane water-dispersion resin prepared by the method described above with a chain extender and then polymerizing with an initiator and an acrylic monomer.

Chain extenders that can be used in the present invention may use monovalent or divalent diamines having at least two reactors, preferably isophorone diamine, hydrazine, ethylene diamine, diethylene diamine, diethylene triamine, triethyl Amines and hexamethylene diamine. The addition amount of the chain extender may be appropriately selected according to the equivalent ratio of unreacted isocyanate, preferably 60 to 90%, most preferably 70 to 80% based on the equivalent ratio of unreacted isocyanate. When the amount of the chain extender added is less than 60%, the molecular weight decreases and the coating film properties decrease. When the amount of the chain extender exceeds 90%, the particles decrease in size, resulting in poor plasticity. In the chain extension, the reaction proceeds at 80 ° C. or lower, preferably 60 ° C. or lower.

The initiator used in the present invention may be freely selected from water-soluble or oil-soluble initiators generally used in the art, provided that the reaction temperature can be used at 60 ° C to 80 ° C. Initiators include, but are not limited to, benzoyl peroxide (BPO), or AIBN (2,2-azo bis-iso butyronitrile), for example.

Acrylic monomers used in the present invention are styrene, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, ethyl (meth) acrylate, isobutyl (meth) acrylate, 2-hydroxy (Meth) acrylate, 2-hydroxy ethyl (meth) acrylate, 2-hydroxy propyl (meth) acrylate, 2-hydroxy butyl (meth) acrylate, 1,3-butanediol di (meth) acrylate , 1,4-butanediol di (meth) acrylate ethylene glycol di (meth) acrylate, and 1,6-hexanediol di (meth) acrylate. The said acrylic monomer can be used individually or in mixture.

20 to 60 parts by weight, 0.5 to 4.0 parts by weight and 20 to 60 parts by weight of the polyurethane water dispersion resin, the initiator and the acrylic monomer used to polymerize the polyurethane-acrylic resin according to the present invention are used. If the amount of the polyurethane water dispersion resin is less than 20 parts by weight, the synthesis is unstable, and if it exceeds 60 parts by weight, the water resistance is lowered. If the amount of the initiator is less than 0.5 parts by weight, the synthesis is unstable, and if it exceeds 4.0 parts by weight, the coating film properties are lowered. If the amount of the acrylic monomer is less than 20 parts by weight, the coating film properties are lowered. If it exceeds 60 parts by weight, the synthesis is unstable.

The prepared polyurethane-acrylic water-dispersed resin has an average particle diameter of about 150 to 250 nm, the solid content is preferably 35 to 50% by weight. In addition, the weight average molecular weight of the polyurethane-acrylic water-dispersion resin according to the present invention is 20,000 to 200,000, preferably 50,000 to 150,000, most preferably 70,000 to 100,000. If the weight average molecular weight is less than 20,000, the coating film properties are lowered, and if it exceeds 200,000, the compactness of the coating film is insufficient.

The acid value of the polyurethane-acrylic water dispersion resin is 5 to 30 mgKOH / g, preferably 5 to 25 mgKOH / g, and most preferably 10 to 20 mgKOH / g. If the acid value is less than 5 mgKOH / g, the pigment is poorly wetted, so that it is not dispersed efficiently.If the acid value is more than 30 mgKOH / g, the viscosity of the colorant is high and the stickiness is very sticky. This happens.

The minimum film forming temperature (MFFT) is 0 to 30 ° C, most preferably 10 to 20 ° C. If the minimum film forming temperature is less than 0 ° C., the surface of the water-based colorant composition is sticky and difficult to apply. If the minimum film forming temperature is more than 30 ° C., the paint using the skinning and water-based colorant composition is easily broken.

In addition, the content of the polyurethane-acrylic water-dispersible resin in the water-based colorant composition according to the present invention is 15 to 25 parts by weight based on the total amount of the water-based colorant composition. If the content of the polyurethane-acrylic water-dispersed resin is less than 15 parts by weight, fluidity is lowered and sedimentation occurs during long-term storage. In addition, when the content exceeds 25 parts by weight, bubbles are severely generated during dispersion, and plasticity characteristics are increased during long-term storage after dispersion, thereby deteriorating workability.

The aqueous dispersant used in the water-based colorant composition according to the present invention is an electrostatic type and includes a nonionic group or an anionic group. Preferred dispersants are, but are not limited to, polyacrylates, modified polyacrylates or mixtures thereof, for example, aqueous dispersants include DISPERBYK 190 from BYK, DISPERS 745W and DISPERS 752W from Tego, SOLSEPERS 44000 from Lubrizol Or 4550, such as Efca's. The acid value of the dispersant is at least 10 mgKOH / g, preferably 10 to 100 mgKOH / g, most preferably 40 to 80 mgKOH / g. If the acid value is less than 10 mgKOH / g, the wettability of the pigment is lowered, and if the acid value is more than 100 mgKOH / g, the water resistance may be weak.

The amount of the dispersant used in the water-based colorant composition according to the present invention may be selected from various ranges according to the kind and properties of the pigment used, preferably 10 to 20 parts by weight, more preferably 12 to 18 parts by weight. . If the amount of the dispersant is less than 10 parts by weight, the room temperature and heat storage stability of the colorant after dispersion is insufficient, and if it exceeds 20 parts by weight, the water resistance becomes weak after the coating film is formed.

In particular, the solids content of the dispersant should be maintained at 0.6 ~ 1.0 times the solids content of the polyurethane-acrylic water dispersion resin. If the solid content of the dispersant is less than 0.6 times the solid content of the polyurethane-acrylic water-dispersion resin, it is difficult to efficiently disperse during dispersion process (dispersion particle size less than 3㎛), and the color of high saturation does not appear. As a result, the water resistance is lowered and color discoloration is caused by water deposition.

Solvents used in the present invention include butyl cellosolve, butyl carbitol, dipropylglycol monoether, propylene glycol, ethylene glycol, and the like, and the amount of the solvent contained in the water-based colorant composition is 2 to 6 parts by weight, preferably Preferably from 2 to 4 parts by weight. If the amount of the solvent is less than 2 parts by weight, there is a fear of compatibility of the colorant to various paints and corruption during long-term storage. Moreover, when it exceeds 6 weight part, there exists a problem of reducing the adhesive force and durability of paint.

The wetting agent used in the present invention is not particularly limited, but a preferred wetting agent is acetylene glycol. The amount of the humectant included in the water-based colorant composition is 0.5 to 2 parts by weight, preferably 1 to 2 parts by weight. The use of less than 0.5 parts by weight of the wetting agent does not provide sufficient wetting of the substrate, and the use of more than 2 parts by weight results in poor repainting and subsequent coating workability.

The pigment used in the present invention is not particularly limited, but for example, carbon black including carboxylic acid, microiron oxide yellow, microtitanium oxide, phthalocyanine blue, phthalocyanine green, quinacridone red or perylene red, etc. It includes. The amount of the pigment included in the water-based colorant composition is 30 to 40 parts by weight, most preferably 30 to 35 parts by weight. If the amount of the pigment is less than 30 parts by weight, the hiding power is lowered, and if it exceeds 40 parts by weight, the adhesion is inferior.

The neutralizer used in the present invention improves the storage stability of the dispersed colorant and adjusts the pH. Neutralizers include, but are not limited to, ammonia, triethylamine, diethanolamine, N, N-dimethylethanolamine, 2-amino-2-methyl-1-propanol, N, N-diethylethanolamine, Group consisting of 2-dimethylamino-2-methyl-1-propanol, monoisopropanol, triisopropanolamine, tributylamine, monoethanolamine, triethanolamine, N-methyldiethanolamine, N-methyldiethanolamine and morpholine It includes at least one selected from. The neutralizing agent contained in the water-based colorant composition is 2 to 8 parts by weight, preferably 4 to 6 parts by weight, and the pH of the colorant is 7 to 10 after the pH is adjusted. If the amount of the neutralizing agent is less than 2 parts by weight, the heat storage stability of the colorant is lowered. If it exceeds 8 parts by weight, small particles precipitate as excess amine reacts with the composition.

The present invention also relates to automotive paints comprising the water-based colorant composition according to the present invention. The content of the water-based colorant composition according to the present invention is 1 to 25 parts by weight, 1 to 10 parts by weight, most preferably 3 to 5 parts by weight based on the total coating composition. If it is less than 1 part by weight, it is difficult to express hue and saturation, and if it exceeds 25 parts by weight, physical properties of the coating film may be reduced. The coating composition of the present invention includes 40 to 60 parts by weight of acrylic main resin, 20 to 40 parts by weight of deionized water, 10 to 20 parts by weight of crude, 1 to 5 parts by weight of wax, and 1 to 3 parts by weight of thickener together with the colorant. . Cosolvents include propanol or butanol, which have a relatively high evaporation rate, and butyl cellosolve, butyl carbitol, 2-ethylhexanol, or hexyl cellosolve, which are somewhat slow in medium speed, for viscosity control and pseudoplasticity. The thickener is, for example, an alkali swirlable type.

Hereinafter, the present invention will be described using examples, but the present invention is only for understanding of the present invention, and the scope of the present invention is not limited thereto in any sense.

Production Example  1: Preparation of Polyester Resin

In a reactor equipped with a stirrer, a thermometer, a condenser and a nitrogen injection tube, 303.70 g of 1,6-hexanediol, 156.23 g of neopentyl glycol, 146.14 g of adipic acid, 139.56 g of isophthalic acid, and 195.58 g of hexahydrophthalic anhydride were added. After the addition, the temperature was raised to 130 ° C, 0.95 g of dibutyltin dilaurate was added as a catalyst, and the temperature was raised to 180 ° C for reaction. When the acid value of the resin (the reactant) was about 20 mgKOH / g, the temperature was raised to 220 ° C. and reacted until the acid value became 5 mgKOH / g or less. When the acid value was 5 mgKOH / g or less, nitrogen was blown to remove residual water and cooled. The acid value of the prepared resin was 3 ~ 5 mgKOH / g, the hydroxyl value was 50 ~ 60 mgKOH / g, the weight average molecular weight was about 2,000.

Production Example  2: polyurethane Water dispersion  Preparation of Resin

Into a reactor equipped with a stirrer, a thermometer, a condenser, a metering pump, and a nitrogen injection tube, 1000 g of the polyester obtained in Preparation Example 1 was placed therein, 25 g of dimethylol propionic acid, 150 g of isophorone diisocyanate, and dibutyltin dilaurate 0.5 After adding g, the temperature was raised to 60 ° C., acetone 300 was added and maintained for 10 hours, and when the NCO content was 0, 15 g of triethylamine was added and maintained for 30 minutes, and 2000 g of deionized water was added for 30 minutes. Dispersion was carried out. When dispersion of the turbidity was completed, acetone was removed under reduced pressure to obtain a polyurethane water dispersion resin having a solid content of 40% by weight and a particle size of 0.1 to 0.2 μm.

Production Example  3: polyurethane-acrylic Water dispersion  Preparation of Resin

1000 g of polyester obtained in Preparation Example 1 was placed in a reactor equipped with a stirrer, a thermometer, a condenser, a metering pump, and a nitrogen injection tube, 237 g of HMDI (Bayer's diisocyanate), 485 g of IPDI (Bayer's, isocyanate) and DMBA (Dimethylol Butanonic). acid) 168g, NMP 800g, DBTDL (Dibutyltin dilaurate) 2g was added and reacted at 90 ℃ for 3 hours in a nitrogen atmosphere. If the NCO% is measured within 3.5%, the reactant is cooled to room temperature and neutralized by adding 67 g of TEA (Triethylamine). After about 30 minutes, distilled water is added to obtain a polyurethane prepolymer dispersion with NCO end groups. Chain extension was added with 39 g of HH (hydrazine hydrate) in the same equivalent ratio as the unreacted NCO at the end of the chain and stirred at room temperature for 2 hours. Thereafter, 7 g of AIBN (2,2-azo bis-isobutyronitrile), 902 g of SM (styrene monomer) and 705 g of 2-EHA (2-ethylhydroxylacylate) are mixed to prepare a pre-emulsion, which is added to the flask over 2 hours. The reaction temperature at this time was maintained at 75-80 degreeC. After completion of the reaction, neutralization was performed by adding dimethylethanol amine (DMEA), and the pH was adjusted to 8.0 to 8.5. The aqueous dispersion resin prepared as described above has a solid content of about 35% by weight, an acid value of 5 to 30 (mgKOH / g), a particle size of 150 to 250 nm, and a viscosity of 50 to 200 cps.

Example  1 and Comparative example  1 to 4

The resin, water, dispersant, antifoaming agent, pigment and additives obtained in Preparation Examples 1 to 3 were mixed in the amounts shown in Table 1 and then dispersed for 2 to 4 hours using a basket milling machine. The final particle size of the dispersion was set to 1 µm or less.

Tego752W [Degussa]: Anionic Modified Polyacrylate

Surfynol 104 [air product]: tetramethyl decynediol

FormStar324 [Cognis]: Block Polymer

Sicotrans L1916 [Basp]: transparent iron oxide

AMP95 [Angus]: 2-amino-2-methyl-1-propanol

Test Example  1: Physical property test of colorant

The water-based colorant compositions of Examples 1 and Comparative Examples 1 to 4 were tested for particle size, fluidity drop, sedimentation, viscosity at room temperature and heat storage, and saturation at room temperature and heat storage. Each test was carried out by the following method.

1. Particle size: The headquarters were analyzed by Master2000 particle size analyzer.

2. Lowering fluidity: A Brookfield Viscometer DV∥ + was used. The viscosity values (thyxotropic index) measured at the shaft rotation speed of 5 rpm and 50 rpm were divided and judged according to the following criteria.

Excellent: 1 <thixotropic index <2

Good: 2 <thixotropic index <4

Bad: 4 <thixotropic index

3. Sedimentation: It was visually confirmed and judged according to the following criteria.

Excellent: no change

Good: sediment present but can be stirred by hand

Poor: Sediment present, unable to stir by hand

4. Viscosity at room temperature and high temperature storage: 200 ml each of the water-based colorant compositions of Examples 1 and Comparative Examples 1 to 4 in two 300ml glass bottles, one left at 45 ℃ for 7 days, the rest at room temperature for more than 3 months It was.

Excellent: KU viscosity value is within 15%

Good: KU viscosity value is within 15-30%

Poor: KU viscosity value of 30% or more

5. Color difference at room temperature and high temperature storage: Mixing 895g of acrylic urethane-acrylic water-dispersion resin (product name: CHU00055), 35g of butyl cellosolve and 35g of Surfynol104BC (product of Air Products) as the main resin for water-based automotive paints To prepare a clear base. 10 g of the colorant described in "4. Viscosity at room temperature and high temperature storage" and 90 g of said clear base were mixed. After performing the bar coater operation to about 50㎛ wet coating film on a transparent plastic film and cured at 80 ℃ 20 minutes, the saturation was measured by ColorEye 7000A was determined according to the following criteria. Each test result is shown in Table 2.

Excellent: color difference <1.0

Good: 1.0 <color difference <2.0

Poor: 2.0 <color difference

Test Example  2: Physical Properties of Coating Composition

1. Stability: Viscosity change ratio (Pod Cup # 4, 25 ° C) was measured after 7 days storage at 50 ° C, and was determined according to the following criteria. Each test result is shown in Table 2.

Excellent: Ford Cup # 4 viscosity values are within 15%

Good: Pod Cup # 4 viscosity value is within 15-30%

Poor: Pod Cup # 4 viscosity value greater than 30%

2. Heat storage: After 7 days storage at 50 ℃ color separation and color separation was determined according to the following criteria.

Excellent: color difference <0.5

Good: 0.5 <color difference <1.0

Poor: 1.0 <color difference

Test Example  3: Physical properties of multilayer coating

After forming a coating film of intermediate paint (KCC: Coaster Surfer, FU2260 Dark Gray) on a specimen coated with a CR iron plate (KCC: ED-6000), water-based topcoat (KCC: Water Mix, 5 wt% of the colorant of Example 1 and Comparative Examples 1 to 4 was added to WT3060 Slick Silver) to form a coating film. After the solvent type 1 liquid clear paint (KCC product: clean sense, TT3060) was coated and cured for 150 ℃ / 20 minutes to prepare a multilayer coating film and the physical properties were measured as follows. The results are shown in Table 2 below.

1. Discoloration: Discoloration was observed after immersion of the specimen at 40 ° C. for 7 days and judged according to the following criteria.

Excellent: color difference <1.0 and no blister

Good: 1.0 <color difference <2.0 and vanishes within 1 hour when blister is produced

Poor: 2.0 <color difference, blister not extinguished within 1 hour

2. Adhesion: 2mm × 2mm size, cross cut and then measured by tape attachment method (ASTM D 3359) (excellent: more than 4B, good: 2B to 3B, poor: less than 2B).

3. Impact: Measured by Dupont Tester 1/2 "500g, 30cm was determined according to the following criteria.

Excellent: No breakage of coating

Good: Fine cracking of the coating film remains

Poor: Broken coating

As shown in Table 2, the water-based colorant composition according to the present invention provides a coating composition having excellent workability and coating properties.

The colorant according to the present invention has good compatibility with water-based paints, there is no deterioration in fluidity even when a large amount of colorant is used, it is excellent in color separation, long-term storage at room temperature and heat storage, stable to sedimentation, and color discoloration by water. This has almost no excellent effect.

Claims (5)

5 to 10 parts by weight of polyurethane water dispersion resin having an anionic function, 15 to 25 parts by weight of polyurethane-acrylic water dispersion resin, 10 to 20 parts by weight of aqueous dispersant, 2 to 6 parts by weight of solvent, 0.5 to 2.0 parts by weight of wetting agent , 30 to 40 parts by weight of a pigment and 2 to 8 parts by weight of a neutralizing agent. The water-based colorant composition according to claim 1, wherein the polyurethane water dispersion resin is neutralized with a tertiary amine and has a degree of neutralization of 40 to 90%. The water-based colorant composition according to claim 1, wherein the acid value of the polyurethane-acrylic water-dispersible resin is 5 to 30 mgKOH / g, the solid content is 35 to 50 wt%, and the minimum film forming temperature is 0 to 30 ° C. . The water-based colorant composition according to claim 1, wherein the water-based dispersant is a polyacrylate having a acid value of 10 to 100 mgKOH / g, a modified polyacrylate, or a mixture thereof. A paint comprising the water-based colorant composition of claim 1.