Encapsulated pigment as well as preparation method and application thereof

Abstract

The invention discloses an encapsulated pigment as well as a preparation method and application thereof, and relates to the technical field of dispersions. The encapsulated pigment comprises a pigment and a coating layer encapsulated on the surface of the pigment; the coating layer is prepared by cross-linking and curing a dispersing agent and a coating agent containing an epoxy group and an anchoring chain segment; the dispersing agent is obtained by reacting a carboxylic acid group monomer with a hydrophobic anchoring group monomer; the dosage of the anchoring group monomer and the carboxylic group monomer meets the requirement that the theoretical acid value is 70 mgKOH / g-176 mgKOH / g; wherein the theoretical acid value is equal to [56.1 / total mass of monomers] * # imgabs0 # * 1000; the solubility of the coating agent in water is less than 1wt%. The encapsulated colorant has good dispersion stability and filtration stability.

Description

Technical Field

[0001] The invention relates to the technical field of dispersions, and in particular to an encapsulated colorant and a preparation method and application thereof. Background Art

[0002] In addition to dispersants, common pigment dispersion systems generally contain a variety of functional additives, such as alcohol ether solvents, wetting agents, penetrants, and surface tension regulators. These additives are prone to competitive adsorption with dispersants, resulting in dispersant desorption failure. In addition, changes in ambient temperature will also weaken the adsorption effect of dispersants and pigments, causing thermal desorption or cold precipitation of dispersants. Therefore, for pigment dispersion systems with high stability requirements, the problem of dispersant desorption will limit the addition of functional additives, which not only affects the improvement of the dispersion function, but also may lead to a decrease in the stability of the dispersion system.

[0003] In the related art, the colorant encapsulation reaction using a hydroxyl-containing dispersant and a diisocyanate crosslinking agent only improves the cold precipitation / thermal desorption and solvent-resistant dispersion stability of the dispersion, but does not improve the filtration stability; the colorant encapsulation reaction using a carboxylic acid-containing dispersant and a dihydrazide crosslinking agent only improves the thermal desorption and solvent-resistant dispersion stability of the dispersion, but does not perform cold precipitation tests and improve filtration stability. Although the above methods solve the problem of competitive adsorption of dispersants and the problem of dispersant desorption caused by ambient temperature, the problem of filtration stability has not been effectively improved. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides an encapsulated colorant with good dispersion stability and filtration stability.

[0005] The invention also provides a method for preparing the encapsulated colorant.

[0006] The present invention also provides a colorant dispersion comprising the encapsulated colorant.

[0007] The present invention also provides the use of the above encapsulated pigment or pigment dispersion.

[0008] According to an embodiment of the first aspect of the present invention, an encapsulated pigment comprises a pigment and a coating layer encapsulated on the surface of the pigment; the coating layer is prepared by cross-linking and curing a dispersant and a coating agent containing an epoxy group and an anchoring segment; The dispersant is obtained by reacting a carboxylic acid monomer and a hydrophobic anchor monomer; the amounts of the anchor monomer and the carboxylic acid monomer satisfy a theoretical acid value of 70 mgKOH / g to 176 mgKOH / g; Where, theoretical acid value = [56.1 / total weight of monomer]* *1000; 56.1 is the molecular weight of potassium hydroxide; total mass of monomers = the sum of the mass of monomers reacted in the dispersant; i An item representing a carboxylic acid-based monomer; M i Carboxylic acid monomer i The number of moles; A i Single carboxylic acid monomer i The average number of carboxylic acid groups in a given molecule (e.g., maleic acid contains 2 carboxylic acid groups per molecule and methacrylic acid contains 1 carboxylic acid group per molecule); The solubility of the coating agent in water is less than 1 wt %.

[0009] The encapsulated colorant according to the embodiment of the present invention has at least the following beneficial effects: The encapsulated pigment of the embodiment utilizes a dispersant with anchoring ability and hydrophobicity, and is combined with a coating agent with low water solubility and an anchoring structure, so as to enhance the integrity of pigment encapsulation, reduce colloidal impurities and other by-products generated during the coating process, effectively improve the dispersion stability and filtration stability of the encapsulated pigment, and reduce problems such as nozzle clogging and broken holes.

[0010] According to some embodiments of the present invention, the structure of the encapsulating agent is substituted R; wherein the number of substitutions is from single substitution to the maximum number of substitutions; the substitution is , , wherein R refers to an anchoring segment.

[0011] According to some embodiments of the present invention, R is selected from substituted or unsubstituted C6~C 20 Aliphatic hydrocarbons, substituted or unsubstituted C6~C 20 Aromatic ring, substituted or unsubstituted C3~C 20 Heterocyclic ring.

[0012] According to some embodiments of the present invention, R is selected from the following structural formula: , , , , , , , , , .

[0013] According to some embodiments of the present invention, the solubility of the coating agent in water (25° C.) is not higher than 0.5 wt %.

[0014] According to some embodiments of the present invention, the coating agent includes at least one of sorbitol glycidyl ether, hydrogenated bisphenol A diglycidyl ether, 1,6-hexanediol diglycidyl ether, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, 3,3'5,5'-tetramethylbiphenyl bisphenol diglycidyl ether, N,N,N,N,-tetraepoxypropyl-4,4-diaminodiphenylmethane, triglycidyl p-aminophenol, triglycidyl isocyanurate, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-2,2-bis[4-(4-aminophenoxy)phenyl]propane, N,N-di(glycidyl)aniline, and 1,2-cyclohexanedicarboxylic acid diglycidyl ester.

[0015] According to some embodiments of the present invention, the method for preparing the dispersant comprises the following steps: In an inert gas atmosphere, a first mixture containing an anchoring group monomer, a carboxylic acid group monomer and an initiator is prepared and subjected to a polymerization reaction to obtain the dispersant.

[0016] According to some embodiments of the present invention, the carboxylic acid-based monomer includes at least one of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, citraconic acid, 4-vinylbenzoic acid, β-(acryloyloxy)propionic acid, and methacryloyloxyethyl succinate.

[0017] According to some embodiments of the present invention, the mass ratio of the anchoring group monomer to the carboxylic acid group monomer is (4.5-9):1.

[0018] According to some embodiments of the present invention, the theoretical oil-water partition coefficient of the anchoring group monomer LogP≧2.0; According to some embodiments of the present invention, the anchoring group monomer includes at least one of styrene and hydrophobic acrylate; According to some embodiments of the present invention, the first mixture further comprises at least one of a first solvent and a buffer monomer. According to some embodiments of the present invention, the buffer monomer includes at least one of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, etc.; According to some embodiments of the present invention, the mass ratio of the buffer monomer to the anchoring group monomer is (0.1-0.5):1.

[0019] The method for preparing the encapsulated colorant according to the second aspect of the present invention comprises the following steps: The second mixture containing the pigment and the dispersant is mixed with the coating agent to carry out a cross-linking reaction, thereby obtaining the encapsulated pigment.

[0020] According to some embodiments of the present invention, the temperature of the cross-linking reaction is 50°C to 90°C.

[0021] According to some embodiments of the present invention, the cross-linking reaction time is 5 h to 20 h.

[0022] According to some embodiments of the present invention, the mass ratio of the colorant to the dispersant is 1:(0.125~3).

[0023] According to some embodiments of the present invention, the mass ratio of the colorant to the coating agent is 1:(0.0125~0.3).

[0024] A pigment dispersion according to an embodiment of the third aspect of the present invention comprises the above-mentioned encapsulated pigment and optional auxiliary agents.

[0025] According to the fourth aspect of the present invention, the encapsulated colorant or the colorant dispersion is used in coatings, printing inks, displays, textile printing or inkjet inks. DETAILED DESCRIPTION

[0026] The following will be combined with the embodiments to clearly and completely describe the concept of the present invention and the technical effects produced, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0027] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0028] In the description of the present invention, if there is a description of first, second, third, etc., it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the sequence of the indicated technical features.

[0029] When a numerical range is disclosed herein, the above range is considered to be continuous and includes the minimum and maximum values ​​of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0030] In the description of the present invention, LogP is a theoretical calculated value. LogP can be calculated using PhysChemSuite software from ACD / Labs, or can be obtained from the website https: / / www.chemspider.com / .

[0031] Unless otherwise specified, "parts by mass" refers to the basic unit of measurement for expressing the mass ratio of multiple components. 1 part can represent any unit mass, such as 1 g or 2.689 g. If we say that the mass of component A is a parts and the mass of component B is b parts, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it means that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, indicating a multiple factor). The sum of the mass of all components is not limited to 100 parts.

[0032] Unless otherwise specified, "room temperature" in the present invention means (25±5)°C.

[0033] If no special instructions are given, the particle size D 50 The results were determined by dynamic light scattering (DLS).

[0034] “And / or” is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0035] The term "not higher than" means less than or equal to, and should be understood to include the number itself.

[0036] The term "dispersion stability" refers to stability upon static storage.

[0037] The term "filtration stability" refers to the dynamic stability of the fluid passing through the filter membrane (simulating the nozzle orifice).

[0038] According to an embodiment of the first aspect of the present invention, an encapsulated pigment comprises a pigment and a coating layer encapsulated on the surface of the pigment; the coating layer is prepared by cross-linking and curing a dispersant and a coating agent containing an epoxy group and an anchoring segment; The dispersant is obtained by reacting a carboxylic acid monomer and a hydrophobic anchor monomer; the amounts of the anchor monomer and the carboxylic acid monomer satisfy a theoretical acid value of 70 mgKOH / g to 176 mgKOH / g; Where, theoretical acid value = [56.1 / total weight of monomer]* *1000; 56.1 is the molecular weight of potassium hydroxide; total mass of monomers = the sum of the mass of monomers reacted in the dispersant; i An item representing a carboxylic acid-based monomer; M i Carboxylic acid monomer iThe number of moles; A i Single carboxylic acid monomer i The average number of carboxylic acid groups in a given molecule (e.g., maleic acid contains 2 carboxylic acid groups per molecule and methacrylic acid contains 1 carboxylic acid group per molecule); The solubility of the coating agent in water (25° C.) is less than 1 wt %.

[0039] If an epoxy-containing dispersant (obtained by the reaction of an unsaturated epoxy monomer and an unsaturated and hydrophobic anchor monomer) and a coating agent containing a carboxylic acid group and an anchor segment are used to encapsulate the pigment, the encapsulated pigment will not have good dispersion stability and filtration stability because the epoxy group does not have the electrostatic repulsion and steric hindrance capabilities required for dispersion stability.

[0040] According to some embodiments of the present invention, the theoretical acid value of the dispersant is 80 mgKOH / g to 170 mgKOH / g. The total mass of monomers, the total molar number of carboxylic acid monomers, and the average number of carboxylic acid groups used to calculate the theoretical acid value are all calculated based on the feeding situation. If the theoretical acid value is too high, it is easy to cause the anchoring ability of the dispersant to decrease and the concentration of free dispersant in the aqueous phase to be too high. If the theoretical acid value is too low, the encapsulation crosslinking degree is insufficient or the solubility is decreased due to the reduction of crosslinkable groups / carboxylic acid groups, and the dispersant is prone to cold precipitation problems.

[0041] According to some embodiments of the present invention, the theoretical acid value of the dispersant is 90 mgKOH / g to 165 mgKOH / g. For example, it can be 90 mgKOH / g, 95 mgKOH / g, 100 mgKOH / g, 105 mgKOH / g, 110 mgKOH / g, 115 mgKOH / g, 120 mgKOH / g, 125 mgKOH / g, 130 mgKOH / g, 135 mgKOH / g, 140 mgKOH / g, 145 mgKOH / g, 150 mgKOH / g, 155 mgKOH / g, 160 mgKOH / g or 165 mgKOH / g.

[0042] According to some embodiments of the present invention, the encapsulating agent contains at least 2 cross-linkable epoxy groups.

[0043] According to some embodiments of the present invention, the encapsulating agent contains 2 to 4 cross-linkable epoxy groups, for example, 2, 3 or 4 cross-linkable epoxy groups.

[0044] According to some embodiments of the present invention, the structure of the encapsulating agent is substituted R; wherein the number of substitutions is from single substitution to the maximum number of substitutions; the substitution is , , wherein R refers to an anchoring segment.

[0045] According to some embodiments of the present invention, the number of substitution is monosubstitution, disubstitution, trisubstitution or tetrasubstitution.

[0046] According to some embodiments of the present invention, R is selected from substituted or unsubstituted C6~C 20 Aliphatic hydrocarbons, substituted or unsubstituted C6~C 20 Aromatic ring, substituted or unsubstituted C3~C 20 Heterocycle: The heterocycle refers to an aliphatic ring containing nitrogen, sulfur and / or oxygen.

[0047] According to some embodiments of the present invention, the substitutions in R are each independently hydroxyl, C1-C 12 Alkyl, C3-C 12 Cycloalkyl, C6-C 18 is substituted by at least one of the aromatic groups.

[0048] According to some embodiments of the present invention, R is selected from the following structural formula: , , , , , , , , , .

[0049] According to some embodiments of the present invention, the anchoring segment has affinity with the pigment, thereby increasing the probability of the coating agent being adsorbed on the pigment surface, reducing the desorption of the dispersant, and increasing the hydrophobicity of the coating agent, reducing the problem of side reactions in the water phase.

[0050] According to some embodiments of the present invention, the solubility of the coating agent in water (25° C.) is not higher than 0.5 wt %.

[0051] According to some embodiments of the present invention, the solubility of the coating agent in water (25° C.) is not higher than 0.25 wt %.

[0052] According to some embodiments of the present invention, the solubility of the coating agent in water (25° C.) is not higher than 0.1 wt %.

[0053] The greater the solubility of the coating agent in water, the greater the concentration of the coating agent free in water, and the easier it is to produce side reactions with the dispersant, thus affecting the filtration stability of the dispersion of the encapsulated colorant.

[0054] According to some embodiments of the present invention, the coating agent includes sorbitol glycidyl ether (DENACOL EX-622, insoluble in water (25°C)), hydrogenated bisphenol A diglycidyl ether (DENACOL EX-252, insoluble in water (25°C)), 1,6-hexanediol diglycidyl ether (DENACOL EX-212, insoluble in water (25°C)), bisphenol A diglycidyl ether (CAS 1675-54-3, insoluble in water (25°C)), bisphenol F diglycidyl ether (CAS 2095-03-6, insoluble in water (25°C)), 3,3'5,5'-tetramethylbiphenyl bisphenol diglycidyl ether (CAS 85954-11-6, insoluble in water (25°C)), N,N,N,N,-tetraepoxypropyl-4,4-diaminodiphenylmethane (CAS 28768-32-3, insoluble in water (25°C)), triglycidyl p-aminophenol (CAS 5026-74-4, insoluble in water (25°C)), triglycidyl isocyanurate (CAS 2451-62-9, solubility in water (25°C) 0.1% by mass), 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane (CAS 65992-66-7, insoluble in water (25°C)), N,N,N',N'-tetraglycidyl-2,2-bis[4-(4-aminophenoxy)phenyl]propane (CAS 110580-47-7, insoluble in water (25°C)), N,N-di(glycidyl)aniline (CAS 2095-06-9, solubility in water (25°C) 0.224% by mass), diglycidyl 1,2-cyclohexanedicarboxylate (CAS 5493-45-8, insoluble in water (25°C)).

[0055] According to some embodiments of the present invention, the dispersant is obtained by free radical polymerization of an unsaturated carboxylic acid monomer and a hydrophobic unsaturated anchor monomer.

[0056] According to some embodiments of the present invention, the dispersant contains at least one cross-linkable carboxyl group.

[0057] According to some embodiments of the present invention, the method for preparing the dispersant comprises the following steps: In an inert gas atmosphere, a first mixture containing an anchoring group monomer, a carboxylic acid group monomer and an initiator is prepared and subjected to a polymerization reaction to obtain the dispersant.

[0058] The cross-linkable carboxylic acid groups of the carboxylic acid-containing dispersant are randomly distributed at any position of the dispersant structure and are not limited to the hydrophobic anchor segment or the hydrophilic carboxylic acid segment.

[0059] According to some embodiments of the present invention, the theoretical oil-water partition coefficient of the anchoring group monomer LogP≧2.0. Thus, the hydrophobicity of the first anchoring segment of the dispersant can be increased, and the concentration of the free dispersant in the aqueous phase can be reduced, thereby achieving the effect of reducing side reactions. If the LogP is less than 2.0, the pigment affinity is weak, and it is easy to be free in the aqueous phase and cannot be effectively adsorbed on the surface of the pigment, which can easily lead to unstable dispersion effect, and byproducts free in water are easily generated during coating, resulting in poor filtration stability.

[0060] According to some embodiments of the present invention, the theoretical oil-water partition coefficient LogP of the anchoring group monomer is 2 to 8. For example, it can be 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5 or 8.

[0061] The anchoring monomers are selected according to the principle of like attracts like, and are matched based on the hydrophobic molecular structure on the surface of the pigment, so that the adsorption and anchoring effect of the anchoring monomer on the pigment surface is optimal. The anchoring structure of the affinity pigment can enhance the anchoring ability of the dispersant and increase the adsorption amount of the dispersant on the pigment surface, making the pigment encapsulation more complete. The carboxylic acid group on the dispersant can increase the water solubility through saltization, and can generate electrostatic repulsion to stabilize the pigment dispersion. The electrostatic repulsion has a strong stabilizing effect, is easy to produce and has low cost, and can be well applied to the preparation of stable dispersions.

[0062] According to some embodiments of the present invention, the anchoring group monomer includes at least one of styrene (LogP=2.7) and hydrophobic acrylate.

[0063] According to some embodiments of the present invention, the hydrophobic acrylate includes 2-ethylhexyl methacrylate (LogP=4.88), 2-ethylhexyl acrylate (LogP=4.33), 2 (propoxy) nonylphenol acrylate (Miramer M1602, South Korea, LogP=6.14), (ethoxy) 4-nonylphenol acrylate (CAS 50974-47-5, LogP=5.14), 2-phenoxyethyl acrylate (LogP=2.71), 2-phenoxyethyl methacrylate (LogP=3.26), o-phenylphenoxyethyl acrylate (LogP=4.22), butyl acrylate (LogP=2.39), butyl methacrylate (LogP=2.94), benzyl acrylate (LogP=2.27), benzyl methacrylate (LogP=2.82), phenyl methacrylate (LogP=2.82), isobornyl acrylate (LogP=4.22), isobornyl methacrylate (LogP=4.77), 3,3,5-trimethylcyclohexyl acrylate (LogP=4.38), dicyclopentadienyl acrylate (CAS 12542-30-2, LogP=3.35), isodecyl acrylate (LogP=5.39), isodecyl methacrylate (LogP=5.38), 4-tert-butylcyclohexyl acrylate (LogP=4.57), 3-phenoxybenzyl acrylate (LogP=3.71), lauryl acrylate (LogP=6.64), and lauryl methacrylate (LogP=7.19).

[0064] According to some embodiments of the present invention, the carboxylic acid-based monomer contains 1 to 2 cross-linkable carboxylic acid groups.

[0065] According to some embodiments of the present invention, the mass ratio of the anchoring group monomer to the carboxylic acid group monomer is (4.5-9): 1. For example, it may be 4.5:1, 4.7:1, 5:1, 5.2:1, 5.4:1, 5.6:1, 5.8:1, 6:1, 6.2:1, 6.4:1, 6.6:1, 6.8:1, 7:1, 7.2:1, 7.4:1, 7.6:1, 7.8:1, 8:1, 8.2:1, 8.4:1, 8.6:1, 8.8:1 or 9:1.

[0066] According to some embodiments of the present invention, the carboxylic acid monomer includes at least one of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, citraconic acid, 4-vinylbenzoic acid, β-(acryloyloxy) propionic acid, and methacryloyloxyethyl succinate. The carboxylic acid group mainly provides a cross-linkable group for the dispersant, and the salt dissociation produces solubility and electrostatic repulsion, which can stabilize the dispersion of the colorant and carry out the coating cross-linking reaction. If the carboxylic acid group is too little, the cross-linking coating reaction will not be easy to complete, and the dispersion stability of the encapsulated colorant will also be poor; if the carboxylic acid group is too much, the water solubility of the dispersant will be too good, the ability to anchor the colorant will be weakened, and the concentration free in the water phase will increase.

[0067] According to some embodiments of the present invention, in the method for preparing the dispersant, the first mixture further comprises at least one of a first solvent and a buffer monomer. It should be noted that if a buffer monomer is included, when calculating the theoretical acid value of the dispersant, the total mass of the monomers is the sum of the mass of the anchor monomer, the mass of the carboxylic acid monomer and the mass of the buffer monomer.

[0068] According to some embodiments of the present invention, the first solvent includes at least one of ethanol, methanol, isopropanol, acetonitrile, ethyl acetate, acetone, butanone, cyclohexanone, tetrahydrofuran, dipropylene glycol, pyridine, pyrrolidone, N-methylpyrrolidone (NMP), dimethylformamide (DMF), dimethylacetamide (DMA), dimethyl sulfoxide (DMOS), and sulfolane.

[0069] According to some embodiments of the present invention, the mass ratio of the first solvent to the anchoring group monomer is (1-8): 1. For example, it can be 1:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2:1, 2.1:1, 2.2:1, 2.3:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 7.5:1 or 8:1.

[0070] According to some embodiments of the invention, the initiator comprises a free radical initiator.

[0071] According to some embodiments of the present invention, the free radical initiator includes at least one of azobisisoheptanenitrile (Vazo52), azobisisobutyronitrile (Vazo64), azobisisovaleronitrile (Vazo67), dimethyl azobisisobutyrate, azobisisobutyramidine hydrochloride (Vazo56), azobisisobutylimidazole hydrochloride (Vazo44), azoisobutylcyanoformamide, azodimethyl N-2-hydroxybutylpropionamide (Vazo86), azobiscyclohexylcarbonitrile (Vazo88) and azobiscyanovaleric acid (Vazo68), potassium persulfate, sodium persulfate, ammonium persulfate, methyl ethyl ketone peroxide, cyclohexanone peroxide, benzoyl peroxide, lauroyl peroxide, isopropylbenzene hydroperoxide, tert-butyl hydroperoxide, tert-butyl perbenzoate, and tert-butyl pervalerate.

[0072] According to some embodiments of the present invention, the mass ratio of the initiator to the anchoring group monomer is 0.03-0.25: 1. For example, it can be 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24 or 0.25.

[0073] According to some embodiments of the present invention, the buffer monomer includes at least one of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, etc. The buffer monomer is used to connect the buffer zone between the anchor segment and the carboxylic acid segment, thereby improving the efficiency of each segment.

[0074] According to some embodiments of the present invention, the mass ratio of the buffer monomer to the anchoring monomer is (0.1-0.5): 1. For example, it can be 0.1:1, 0.12:1, 0.14:1, 0.16:1, 0.18:1, 0.2:1, 0.21:1, 0.22:1, 0.23:1, 0.24:1, 0.25:1, 0.26:1, 0.27:1, 0.28:1, 0.29:1, 0.3:1, 0.32:1, 0.34:1, 0.36:1, 0.38:1, 0.4:1, 0.42:1, 0.44:1, 0.46:1, 0.48:1 or 0.5:1.

[0075] According to some embodiments of the present invention, the polymerization reaction temperature is 50°C to 100°C. For example, it may be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C or 100°C.

[0076] According to some embodiments of the present invention, the polymerization reaction time is 1 h to 7 h. For example, it can be 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, 4 h, 4.5 h, 5 h, 5.5 h, 6 h, 6.5 h or 7 h.

[0077] According to some embodiments of the present invention, the method for preparing the dispersant further comprises post-polymerization treatment.

[0078] According to some embodiments of the present invention, the polymerization post-treatment comprises at least one of terminating the polymerization and removing the first solvent. Those skilled in the art may choose to remove the first solvent by distillation under reduced pressure.

[0079] According to some embodiments of the present invention, when preparing the dispersant, the polymerization reaction is terminated when the total residual amount (by mass) of the carboxylic acid group monomer and the anchor group monomer is less than 3%.

[0080] According to some embodiments of the present invention, those skilled in the art may terminate the polymerization reaction by adding a free radical inhibitor, wherein the free radical inhibitor comprises at least one of hydroquinone, butylated hydroxytoluene, p-hydroxyanisole, di-tert-butyl-p-cresol, and p-tert-butylcatechol.

[0081] According to some embodiments of the present invention, the amount of the free radical inhibitor added is 0.05wt% to 0.3wt% of the total weight of the monomers. For example, it may be 0.05wt%, 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt% or 0.3wt%. It should be noted that if the first mixture does not contain a buffer monomer, the total weight of the monomers is the sum of the weights of the carboxylic acid monomer and the anchoring monomer; if the first mixture contains a buffer monomer, the total weight of the monomers is the sum of the weights of the carboxylic acid monomer, the buffer monomer and the anchoring monomer.

[0082] According to some embodiments of the present invention, the colorant includes at least one of an organic pigment and a disperse dye.

[0083] According to some embodiments of the present invention, the organic pigment includes at least one of PB15:1, PB15:2, PB15:3, PB15:4, PB15:6, PY12, PY13, PY74, PY138, PY139, PY150, PY151, PY155, PY180, PY183, PY185, PY194, PV19, PV23, PR122, PR146, PR176, PR177, PR254, PR269, PG7, PG36, and PG58.

[0084] According to some embodiments of the present invention, the disperse dye includes at least one of a red disperse dye, a yellow disperse dye, a brown disperse dye, an orange disperse dye, and a blue disperse dye.

[0085] According to some embodiments of the present invention, the red disperse dye includes at least one of red disperse dyes 1, 11, 22, 50, 60, 65, 74, 92, 146, and 239.

[0086] According to some embodiments of the present invention, the yellow disperse dye includes at least one of yellow disperse dyes 7, 23, 42, 51, 54, 60, 65, 82, 98, 114, 160, and 211.

[0087] According to some embodiments of the present invention, the brown disperse dye includes at least one of brown disperse dyes 1, 5, 19, 21, 27, and 30.

[0088] According to some embodiments of the present invention, the orange disperse dye comprises at least one of orange disperse dyes 25, 37, and 119.

[0089] According to some embodiments of the present invention, the blue disperse dye includes at least one of blue disperse dyes 14, 26, 56, 60, 72, 91, 165, 359, 360, and 366.

[0090] A method for preparing an encapsulated colorant according to a second aspect of the present invention comprises the following steps: The second mixture containing the pigment and the dispersant is mixed with the coating agent to carry out a cross-linking reaction, thereby obtaining the encapsulated pigment.

[0091] After the dispersant and the pigment are premixed, the insoluble anchoring segments formed by the anchoring monomers in the dispersant can be adsorbed on the surface of the pigment; after the coating agent is added, the coating agent undergoes a cross-linking reaction with the dispersant adsorbed on the surface of the pigment and coats the pigment to obtain a dispersion containing the encapsulated pigment. The hydrophilic carboxylic acid segments in the coating layer on the surface of the encapsulated pigment can disperse the encapsulated pigment in water, and the electrostatic repulsion and / or steric hindrance generated by the hydrophilic carboxylic acid segments maintain the stability of the dispersion.

[0092] According to some embodiments of the present invention, the mass ratio of the colorant to the dispersant is 1:(0.125-3). For example, it can be 1:0.125, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.2, 1:1.4, 1:1.6, 1:1.8, 1:2, 1:2.2, 1:2.4, 1:2.6, 1:2.8 or 1:3.

[0093] According to some embodiments of the present invention, the mass ratio of the colorant to the coating agent is 1:(0.0125-0.3). For example, it can be 1:0.0125, 1:0.025, 1:0.03, 1:0.035, 1:0.04, 1:0.045, 1:0.05, 1:0.055, 1:0.06, 1:0.065, 1:0.07, 1:0.08, 1:0.09, 1:0.1, 1:0.2 or 1:0.3.

[0094] According to some embodiments of the present invention, the second mixture further comprises at least one of a wetting defoaming agent and a second solvent.

[0095] According to some embodiments of the present invention, the pH of the second mixture is 7 to 10. For example, it can be 7, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9 or 10.

[0096] According to some embodiments of the present invention, the wetting defoamer includes at least one of BYK 011, BYK 012, BYK 013, BYK 014, BYK 015, BYK 016, BYK 017, BYK 018, BYK 019, SURFYNOL 104E, SURFYNOL 107L, SURFYNOL 420, and SURFYNOL 440.

[0097] According to some embodiments of the present invention, the mass ratio of the wetting defoamer to the dispersant is 0.01 to 0.05: 1. For example, it can be 0.01: 1, 0.015: 1, 0.02: 1, 0.025: 1, 0.03: 1, 0.035: 1, 0.04: 1, 0.045: 1 or 0.05: 1.

[0098] According to some embodiments of the invention, the second solvent is water.

[0099] According to some embodiments of the present invention, the mass ratio of the second solvent to the dispersant is (2-20): 1. For example, it can be 2: 1, 2.5: 1, 3: 1, 3.5: 1, 4: 1, 4.5: 1, 5: 1, 5.5: 1, 6: 1, 6.5: 1, 7: 1, 7.5: 1, 8: 1, 9: 1, 10: 1, 11: 1, 12: 1, 13: 1, 14: 1, 15: 1, 16: 1, 17: 1, 18: 1, 19: 1 or 20: 1.

[0100] According to some embodiments of the present invention, the particle size D of the colorant in the second mixture is 50 The range is 50 nm to 200 nm. For example, it can be 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, 160 nm, 170 nm, 180 nm, 190 nm or 200 nm.

[0101] According to some embodiments of the present invention, the method for preparing the second mixture comprises the following steps: The mixture containing the colorant and the dispersant is homogenized to obtain the second mixture.

[0102] According to some embodiments of the present invention, the homogenization treatment includes at least one of a double-roll kneading, a three-roll kneading, a homogenizing mixer, a ball mill, an oscillator, a sand mill, and a high-pressure homogenizer. Thus, the colorant is crushed or ground and dispersed, which is beneficial for the dispersant to disperse the colorant and prevent it from agglomerating.

[0103] According to some embodiments of the present invention, the temperature of the cross-linking reaction is 50°C to 90°C. For example, it may be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C or 90°C.

[0104] According to some embodiments of the present invention, the cross-linking reaction time is 5 h to 20 h. For example, it can be 5 h, 5.5 h, 6 h, 6.5 h, 7 h, 7.5 h, 8 h, 8.5 h, 9 h, 9.5 h, 10 h, 10.5 h, 11 h, 11.5 h, 12 h, 12.5 h, 13 h, 13.5 h, 14 h, 14.5 h, 15 h, 15.5 h, 16 h, 16.5 h, 17 h, 17.5 h, 18 h, 18.5 h, 19 h, 19.5 h or 20 h.

[0105] According to some embodiments of the present invention, the preparation method further comprises post-crosslinking reaction treatment.

[0106] According to some embodiments of the present invention, the post-crosslinking reaction treatment includes removing large aggregated particles. Those skilled in the art can select a suitable method to remove large aggregated particles as needed (such as filtering with a glass fiber filter with a pore size of 1 μm to remove large aggregated particles).

[0107] A pigment dispersion according to a third aspect of the present invention comprises the encapsulated pigment as described in the first aspect and an optional auxiliary agent.

[0108] According to some embodiments of the present invention, the colorant dispersion includes a third solvent.

[0109] According to some embodiments of the invention, the third solvent is water.

[0110] According to some embodiments of the present invention, the concentration of the encapsulated colorant in the colorant dispersion is 10wt% to 60wt%. For example, it can be 10wt%, 12wt%, 14wt%, 16wt%, 18wt%, 20wt%, 22wt%, 24wt%, 26wt%, 28wt%, 30wt%, 32wt%, 34wt%, 36wt%, 38wt%, 40wt%, 42wt%, 44wt%, 46wt%, 48wt%, 50wt%, 52wt%, 54wt%, 56wt%, 58wt% or 60wt%.

[0111] According to some embodiments of the present invention, the auxiliary agent includes at least one of a bactericide, a wetting agent, a humectant, a penetrant, a surface tension adjuster, a pH adjuster, a defoamer, and a leveling agent.

[0112] According to some embodiments of the present invention, the concentration of the auxiliary agent in the colorant dispersion is 0.1wt% to 30wt%. For example, it can be 0.1wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, 21wt%, 22wt%, 23wt%, 24wt%, 25wt%, 26wt%, 27wt%, 28wt%, 29wt% or 30wt%.

[0113] According to the fourth aspect of the present invention, the encapsulated colorant or the colorant dispersion is used in coatings, printing inks, displays, textile printing or inkjet inks.

[0114] Unless otherwise specified, the calculation formula for the theoretical acid value is as follows: Theoretical acid value = [56.1 / total monomer mass]* *1000; Wherein, 56.1 is the molecular weight of potassium hydroxide; total mass of monomers = the sum of the mass of monomers reacted in the dispersant; i An item representing a carboxylic acid-based monomer; M i Carboxylic acid monomer i The number of moles; A i Single carboxylic acid monomer i The average number of carboxylic acid groups.

[0115] Preparation Example 1: Preparation of carboxylic acid-containing dispersant CD1 Nitrogen was introduced into a reaction bottle equipped with a condensing reflux device, and 250 g of butanone and 200 g of isopropanol were added and heated to 70°C. Then, 426.1 g of anchor monomer (2-phenoxyethyl methacrylate, LogP=3.26), 73.9 g of carboxylic acid monomer (allylmalonic acid, each molecule of the compound contains 2 carboxylic acid groups) and 200 g of butanone were mixed to obtain a premixed solution. Then, 75 g of butanone and 25 g of azobisisoheptanenitrile were mixed and stirred until dissolved to obtain an initiator solution. Then, the premixed solution and the initiator solution were slowly added to the reaction bottle at the same time to react. After reacting for 5 hours, the total residual amount of the carboxylic acid monomer and the anchor monomer was detected by HPLC high performance liquid chromatography. When the total residual amount was less than 3%, 0.1% of the total monomer amount of hydroquinone was added to terminate the reaction to obtain a polymer dispersant solution. Then, the solvent was removed by reduced pressure distillation to obtain a carboxylic acid-containing dispersant CD1.

[0116] The theoretical acid value of the carboxylic acid group-containing dispersant CD1 is 115.1.

[0117] Preparation Example 2: Preparation of carboxylic acid-containing dispersant CD2 Nitrogen was introduced into a reaction flask equipped with a condensing reflux device, and 250 g of butanone and 200 g of isopropanol were added and heated to 70°C. Then 440.6 g of anchor monomer (2 (propoxy) nonylphenol acrylate (Miramer M1602, South Korea, structure , n≈2, R'=C9H 19 ), Mw=390, LogP=6.14), 59.4g of carboxylic acid monomer (maleic acid, each molecule of the compound contains 2 carboxylic acid groups) and 200g of butanone are mixed and dissolved to obtain a premixed solution; then 75g of butanone and 25g of azobisisoheptanenitrile are mixed and stirred until dissolved to obtain an initiator solution; then the premixed solution and the initiator solution are slowly added into the reaction bottle at the same time to react; after reacting for 5 hours, the total residual amount of the carboxylic acid monomer and the anchoring monomer is detected by HPLC high performance liquid chromatography, and when the total residual amount is less than 3%, 0.1% of the total monomer amount of hydroquinone is added to terminate the reaction to obtain a polymer dispersant solution; then the solvent is removed by reduced pressure distillation to obtain a carboxylic acid-containing dispersant CD2.

[0118] The theoretical acid value of the carboxylic acid-containing dispersant CD2 is 114.8.

[0119] Preparation Example 3: Preparation of carboxylic acid-containing dispersant CD3 Nitrogen was introduced into a reaction bottle equipped with a condensation reflux device, and 250 g of butanone and 200 g of isopropanol were added and heated to 70°C. Then, 419.8 g of anchor monomer (dicyclopentadienyl acrylate, LogP=3.35), 80.2 g of carboxylic acid monomer (itaconic acid, each molecule of the compound contains 2 carboxylic acid groups) and 200 g of butanone were mixed and dissolved to obtain a premixed solution. Then, 75 g of butanone and 25 g of azobisisoheptanenitrile were mixed and stirred until dissolved to obtain an initiator solution. Then, the premixed solution and the initiator solution were slowly added to the reaction bottle at the same time to react. After reacting for 5 hours, the total residual amount of the carboxylic acid monomer and the anchor monomer was detected by HPLC high performance liquid chromatography. When the total residual amount was less than 3%, 0.1% of the total monomer amount of hydroquinone was added to terminate the reaction to obtain a polymer dispersant solution. Then, the solvent was removed by reduced pressure distillation to obtain a carboxylic acid-containing dispersant CD3.

[0120] The theoretical acid value of the carboxylic acid-containing dispersant CD3 is 138.4.

[0121] Preparation Example 4: Preparation of carboxylic acid-containing dispersant CD4 Nitrogen was introduced into a reaction bottle equipped with a condensing reflux device, and 250 g of butanone and 200 g of isopropanol were added and heated to 70°C. Then, 418.3 g of anchor monomer (benzyl methacrylate, LogP=2.82), 81.7 g of carboxylic acid monomer (methacrylic acid, each molecule of the compound contains 1 carboxylic acid group) and 200 g of butanone were mixed and dissolved to obtain a premixed solution. Then, 75 g of butanone and 25 g of azobisisoheptanenitrile were mixed and stirred until dissolved to obtain an initiator solution. Then, the premixed solution and the initiator solution were slowly added to the reaction bottle at the same time to react. After reacting for 5 hours, the total residual amount of the carboxylic acid monomer and the anchor monomer was detected by HPLC high performance liquid chromatography. When the total residual amount was less than 3%, 0.1% of the total monomer amount of hydroquinone was added to terminate the reaction to obtain a polymer dispersant solution. Then, the solvent was removed by reduced pressure distillation to obtain a carboxylic acid-containing dispersant CD4.

[0122] The theoretical acid value of the carboxylic acid-containing dispersant CD4 is 106.5.

[0123] Preparation Example 5: Preparation of Carboxylic Acid-Containing Dispersant CD5 Nitrogen was introduced into a reaction bottle equipped with a condensation reflux device, and 250 g of butanone and 200 g of isopropanol were added and heated to 70°C. Then, 358.5 g of anchor monomer (2-ethylhexyl methacrylate, LogP=4.88), 82.3 g of buffer monomer (methyl methacrylate, LogP=1.35), 59.2 g of carboxylic acid monomer (acrylic acid, each molecule of the compound contains 1 carboxylic acid group) and 200 g of butanone were mixed and dissolved to obtain a premixed solution. Then, 75 g of butanone and 25 g of azobisisoheptanenitrile were mixed and stirred until dissolved to obtain an initiator solution. Then, the premixed solution and the initiator solution were slowly added to the reaction bottle at the same time to react. After reacting for 5 hours, the total residual amount of the carboxylic acid monomer and the anchor monomer was detected by HPLC high performance liquid chromatography. When the total residual amount was less than 3%, 0.1% of the total monomer amount of hydroquinone was added to terminate the reaction to obtain a polymer dispersant solution. Then, the solvent was removed by reduced pressure distillation to obtain a carboxylic acid-containing dispersant CD5.

[0124] The theoretical acid value of the carboxylic acid-containing dispersant CD5 is 92.2.

[0125] Preparation Example 6: Preparation of carboxylic acid-containing dispersant CD6 Nitrogen was introduced into a reaction bottle equipped with a condensation reflux device, and 250 g of butanone and 200 g of isopropanol were added and heated to 70°C. Then, 431.0 g of anchor monomer (o-phenylphenoxyethyl acrylate, LogP=4.88), 69.0 g of carboxylic acid monomer (allylmalonic acid, each molecule of the compound contains 2 carboxylic acid groups) and 200 g of butanone were mixed and dissolved to obtain a premixed solution. Then, 75 g of butanone and 25 g of azobisisoheptanenitrile were mixed and stirred until dissolved to obtain an initiator solution. Then, the premixed solution and the initiator solution were slowly added to the reaction bottle at the same time to react. After reacting for 5 hours, the total residual amount of the carboxylic acid monomer and the anchor monomer was detected by HPLC high performance liquid chromatography. When the total residual amount was less than 3%, 0.1% of the total monomer amount of hydroquinone was added to terminate the reaction to obtain a polymer dispersant solution. Then, the solvent was removed by reduced pressure distillation to obtain a carboxylic acid-containing dispersant CD6.

[0126] The theoretical acid value of the carboxylic acid-containing dispersant CD6 is 108.2.

[0127] Preparation Example 7: Preparation of carboxylic acid-containing dispersant CD7 Nitrogen was introduced into a reaction bottle equipped with a condensing reflux device, and 250 g of butanone and 200 g of isopropanol were added and heated to 70°C; then 412.9 g of anchor monomer (2-phenoxyethyl methacrylate, LogP=3.26), 87.1 g of maleic acid, each molecule of the compound containing 2 carboxylic acid groups) and 200 g of butanone were mixed to obtain a premixed solution; then 75 g of butanone and 25 g of azobisisoheptanenitrile were mixed and stirred until dissolved to obtain an initiator solution; then the premixed solution and the initiator solution were slowly added to the reaction bottle at the same time to react; after reacting for 5 hours, the total residual amount of the carboxylic acid monomer and the anchor monomer was detected by HPLC high performance liquid chromatography, and when the total residual amount was less than 3%, 0.1% of the total monomer amount of hydroquinone was added to terminate the reaction to obtain a polymer dispersant solution; then the solvent was removed by reduced pressure distillation to obtain a carboxylic acid-containing dispersant CD7.

[0128] The theoretical acid value of the carboxylic acid-containing dispersant CD7 is 168.5.

[0129] Preparation Example 8: Preparation of carboxylic acid-containing dispersant CD8 Nitrogen was introduced into a reaction bottle equipped with a condensation reflux device, and 250 g of butanone and 200 g of isopropanol were added and heated to 70°C. Then, 306.4 g of anchor monomer (2-ethylhexyl methacrylate, LogP=4.88), 82.3 g of buffer monomer (methyl methacrylate, LogP=1.35), 111.3 g of carboxylic acid monomer (acrylic acid, each molecule of the compound contains 1 carboxylic acid group) and 200 g of butanone were mixed and dissolved to obtain a premixed solution. Then, 75 g of butanone and 25 g of azobisisoheptanenitrile were mixed and stirred until dissolved to obtain an initiator solution. Then, the premixed solution and the initiator solution were slowly added to the reaction bottle at the same time to react. After reacting for 5 hours, the total residual amount of the carboxylic acid monomer and the anchor monomer was detected by HPLC high performance liquid chromatography. When the total residual amount was less than 3%, 0.1% of the total monomer amount of hydroquinone was added to terminate the reaction to obtain a polymer dispersant solution. Then, the solvent was removed by reduced pressure distillation to obtain a carboxylic acid-containing dispersant CD8.

[0130] The theoretical acid value of the carboxylic acid-containing dispersant CD8 is 173.4.

[0131] Preparation Example 9: Preparation of carboxylic acid-containing dispersant CD9 Nitrogen was introduced into a reaction bottle equipped with a condensing reflux device, and 250 g of butanone and 200 g of isopropanol were added and heated to 70°C. Then, 451.0 g of anchor monomer (benzyl methacrylate, LogP=2.82), 49.0 g of carboxylic acid monomer (methacrylic acid, each molecule of the compound contains 1 carboxylic acid group) and 200 g of butanone were mixed and dissolved to obtain a premixed solution. Then, 75 g of butanone and 25 g of azobisisoheptanenitrile were mixed and stirred until dissolved to obtain an initiator solution. Then, the premixed solution and the initiator solution were slowly added to the reaction bottle at the same time to react. After reacting for 5 hours, the total residual amount of the carboxylic acid monomer and the anchor monomer was detected by HPLC high performance liquid chromatography. When the total residual amount was less than 3%, 0.1% of the total monomer amount of hydroquinone was added to terminate the reaction to obtain a polymer dispersant solution. Then, the solvent was removed by reduced pressure distillation to obtain a carboxylic acid-containing dispersant CD9.

[0132] The theoretical acid value of the carboxylic acid-containing dispersant CD9 is 63.8.

[0133] Example 1 This embodiment provides an encapsulated colorant, which is composed of a PY74 pigment and a coating layer encapsulated on the surface of the pigment; The coating layer is prepared by cross-linking and curing the dispersant CD1 and the coating agent N, N, N', N'-tetraglycidyl-2,2-bis[4-(4-aminophenoxy)phenyl]propane.

[0134] This embodiment also provides an aqueous dispersion containing the encapsulated colorant, and the preparation method thereof has the following steps (the amount of each component is calculated by weight): (1) Mix 0.4 parts of wetting defoamer BYK-019, 149.6 parts of deionized water and 20 parts of dispersant CD1, adjust the pH to 9 and stir until completely dissolved, then add 30 parts of PY74 pigment and stir until uniform, then introduce into homogenizing equipment to grind or crush the pigment particles (the particle size of the pigment particles after grinding or crushing is D 50 The diameter of the dispersion DP1-0 is not cross-linked and coated. (2) 100 parts of DP1-0 were introduced into a stirring tank, the temperature was raised to 70°C under stirring, and 0.8 parts of N,N,N',N'-tetraglycidyl-2,2-bis[4-(4-aminophenoxy)phenyl]propane was added dropwise to carry out a cross-linking reaction. The mixture was stirred for 8 hours and then cooled to room temperature to obtain a reaction solution. (3) The reaction solution was filtered using a 1.0 μm glass fiber filter to remove large particles agglomerated during the reaction process, thereby obtaining an aqueous dispersion DP1-1 containing encapsulated colorant.

[0135] Example 2 This embodiment provides an encapsulated colorant, which is composed of a PB15:3 pigment and a coating layer encapsulated on the surface of the pigment; The coating layer is prepared by cross-linking and curing the dispersant CD2 and the coating agent sorbitol glycidyl ether (DENACOL EX-622).

[0136] This embodiment also provides an aqueous dispersion containing the encapsulated colorant, and the preparation method thereof has the following steps (the amount of each component is calculated by weight): (1) Mix 0.4 parts of wetting defoamer BYK-019, 89.6 parts of deionized water and 40 parts of dispersant CD2, adjust the pH to 9 and stir until completely dissolved, then add 70 parts of PB15:3 pigment and stir until uniform, then introduce into homogenizing equipment to grind or crush the pigment particles (the particle size of the pigment particles after grinding or crushing is D 50 The diameter of the dispersion DP2-0 is not cross-linked and coated. (2) 100 parts of DP2-0 were introduced into a stirring tank, heated to 70°C under stirring, and then 2.0 parts of DENACOL EX-622 were added dropwise to carry out a cross-linking reaction. The mixture was stirred for 16 hours and then cooled to room temperature to obtain a reaction solution. (3) The reaction solution was filtered using a 1.0 μm glass fiber filter to remove large particles agglomerated during the reaction process, thereby obtaining an aqueous dispersion DP2-1 containing encapsulated colorant.

[0137] Example 3 This embodiment provides an encapsulated colorant, which is composed of a PR122 pigment and a coating layer encapsulated on the surface of the pigment; The coating layer is prepared by cross-linking and curing a dispersant CD3 and a coating agent N, N, N, N, -tetraepoxypropyl-4,4-diaminodiphenylmethane.

[0138] This embodiment also provides an aqueous dispersion containing the encapsulated colorant, and the preparation method thereof has the following steps (the amount of each component is calculated by weight): (1) Mix 0.4 parts of wetting defoamer BYK-019, 119.6 parts of deionized water and 30 parts of dispersant CD2, adjust the pH to 9 and stir until completely dissolved, then add 50 parts of PR122 pigment and stir until uniform, then introduce into homogenizing equipment to grind or crush the pigment particles (the particle size of the pigment particles after grinding or crushing is D 50 The diameter of the dispersion DP3-0 is not cross-linked and coated. (2) 100 parts of DP3-0 were introduced into a stirring tank, the temperature was raised to 70°C under stirring, and 1.2 parts of N, N, N, N,-tetracyclyl-4,4-diaminodiphenylmethane were added dropwise to carry out a cross-linking reaction. The mixture was stirred for 12 hours and then cooled to room temperature to obtain a reaction solution. (3) The reaction solution was filtered using a 1.0 μm glass fiber filter to remove large particles agglomerated during the reaction process, thereby obtaining an aqueous dispersion DP3-1 containing encapsulated colorant.

[0139] Example 4 This embodiment provides an encapsulated colorant, which is composed of a PK7 pigment and a coating layer encapsulated on the surface of the pigment; The coating layer is prepared by cross-linking and curing a dispersant CD4 and a coating agent bisphenol A diglycidyl ether.

[0140] This embodiment also provides an aqueous dispersion containing the encapsulated colorant, and the preparation method thereof has the following steps (the amount of each component is calculated by weight): (1) Mix 0.4 parts of wetting defoamer BYK-019, 149.6 parts of deionized water and 20 parts of dispersant CD4, adjust the pH to 9 and stir until completely dissolved, then add 30 parts of PR122 pigment and mix until uniform, then introduce into homogenizing equipment to grind or crush the pigment particles (the particle size of the pigment particles after grinding or crushing is D 50 The diameter of the dispersion DP4-0 is not cross-linked and coated. (2) 100 parts of DP4-0 were introduced into a stirring tank, the temperature was raised to 70°C under stirring, and 0.8 parts of bisphenol A diglycidyl ether was added dropwise to carry out a cross-linking reaction. The mixture was stirred for 8 hours and then cooled to room temperature to obtain a reaction solution; (3) The reaction solution was filtered using a 1.0 μm glass fiber filter to remove large particles agglomerated during the reaction process, thereby obtaining an aqueous dispersion DP4-1 containing encapsulated colorant.

[0141] Example 5 This embodiment provides an encapsulated colorant, which is composed of disperse dye blue 359 and a coating layer encapsulated on the surface of the pigment; The coating layer is prepared by cross-linking and curing a dispersant CD5 and a coating agent 1, 6-hexanediol diglycidyl ether (DENACOL EX-212).

[0142] This embodiment also provides an aqueous dispersion containing the encapsulated colorant, and the preparation method thereof has the following steps (the amount of each component is calculated by weight): (1) Mix 0.4 parts of wetting defoamer BYK-019, 134.6 parts of deionized water and 25 parts of dispersant CD4, adjust the pH to 9 and stir until completely dissolved, then add 40 parts of disperse dye blue 359 and stir until uniform, then introduce into the homogenizing equipment to grind or crush the pigment particles (the particle size of the pigment particles after grinding or crushing is D 50 The diameter of the dispersion DP5-0 is not cross-linked and coated. (2) Take 100 parts of DP5-0 and introduce it into a stirring tank. Heat it to 70°C while stirring. Then add 1.2 parts of DENACOL EX-212 dropwise to carry out a cross-linking reaction. Continue stirring for 10 hours and then cool it to room temperature to obtain a reaction solution. (3) The reaction solution was filtered using a 1.0 μm glass fiber filter to remove large particles agglomerated during the reaction process, thereby obtaining an aqueous dispersion DP5-1 containing encapsulated colorant.

[0143] Example 6 This embodiment provides an encapsulated colorant, which is composed of disperse dye yellow 54 and a coating layer encapsulated on the surface of the pigment; The coating layer is prepared by cross-linking and curing a dispersant CD6 and a coating agent 1, 3-bis(N, N-diglycidylaminomethyl)cyclohexane.

[0144] This embodiment also provides an aqueous dispersion containing the encapsulated colorant, and the preparation method thereof has the following steps (the amount of each component is calculated by weight): (1) Mix 0.4 parts of wetting defoamer BYK-019, 134.6 parts of deionized water and 25 parts of dispersant CD4, adjust the pH to 9 and stir until completely dissolved, then add 40 parts of disperse dye yellow 54 and stir until uniform, then introduce into the homogenizing equipment to grind or crush the pigment particles (the particle size of the pigment particles after grinding or crushing is D 50 The diameter of the dispersion DP6-0 is not cross-linked and coated. (2) 100 parts of DP6-0 were introduced into a stirring tank, heated to 70°C under stirring, and then 1.2 parts of 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane were added dropwise to carry out a cross-linking reaction. The mixture was stirred for 10 h and then cooled to room temperature to obtain a reaction solution. (3) The reaction solution was filtered using a 1.0 μm glass fiber filter to remove large particles agglomerated during the reaction process, thereby obtaining an aqueous dispersion DP6-1 containing encapsulated colorant.

[0145] Example 7 This embodiment provides an encapsulated colorant, which is composed of disperse dye red 60 and a coating layer encapsulated on the surface of the pigment; The coating layer is prepared by cross-linking and curing a dispersant CD7 and a coating agent triglycidyl p-aminophenol.

[0146] This embodiment also provides an aqueous dispersion containing the encapsulated colorant, and the preparation method thereof has the following steps (the amount of each component is calculated by weight): (1) Mix 0.4 parts of wetting defoamer BYK-019, 134.6 parts of deionized water and 25 parts of dispersant CD4, adjust the pH to 9 and stir until completely dissolved, then add 40 parts of disperse dye red 60 and stir until uniform, then introduce into the homogenizing equipment to grind or crush the pigment particles (the particle size of the pigment particles after grinding or crushing is D 50 The diameter of the dispersion DP7-0 is not cross-linked and coated. (2) 100 parts of DP7-0 were introduced into a stirring tank, the temperature was raised to 70°C under stirring, and 1.2 parts of triglycidyl p-aminophenol was added dropwise to carry out a cross-linking reaction. The mixture was stirred for 10 h and then cooled to room temperature to obtain a reaction solution. (3) The reaction solution was filtered using a 1.0 μm glass fiber filter to remove large particles agglomerated during the reaction process, thereby obtaining an aqueous dispersion DP7-1 containing encapsulated colorant.

[0147] Comparative Example 1 This comparative example provides an aqueous dispersion, and its preparation method is basically the same as that of Example 1, except that steps (2) and (3) are omitted.

[0148] Comparative Example 2 This comparative example provides an aqueous dispersion, and its preparation method is basically the same as that of Example 5, except that the dispersant CD5 is replaced by dispersant CD8.

[0149] Comparative Example 3 This comparative example provides an aqueous dispersion, and its preparation method is basically the same as that of Example 5, except that the coating agent 1,6-hexanediol diglycidyl ether (DENACOL EX-212) is replaced by water-soluble polyethylene glycol diglycidyl ether.

[0150] Comparative Example 4 This comparative example provides an aqueous dispersion, and its preparation method is basically the same as that of Example 4, except that the dispersant CD4 is replaced by dispersant CD9.

[0151] Test Case The aqueous dispersions prepared in Examples 1 to 7 and Comparative Examples 1 to 4 were tested for dispersion stability and filtration stability.

[0152] 1. Aging test (dispersion stability and filtration stability). The test method and steps are as follows: Each aqueous dispersion was diluted with water to a test sample with a colorant concentration of 5wt%, and the dispersant thermal desorption and cold precipitation test was performed. The test sample was placed in a high temperature environment of 60℃ for 8 h, cooled to room temperature for 4 h, and in a low temperature environment of -20℃ for 8 h, and returned to room temperature for 4 h; the above steps were repeated for 7 days. The particle size of the test sample before and after treatment was detected using the Malvern Nano S90 nanoparticle size analyzer from the UK. The viscosity of the test sample before and after treatment (25℃) was detected using the Brookfield DV2T cone and plate viscometer from the United States. The treated test sample was filtered using a PVDF filter membrane with a pore size of 1.0 μm under a negative pressure of 90 KPa, and the time required to filter 1 kg of the test sample (i.e., the filtration time) was recorded. The smaller the change or the shorter the filtration time, the better the stability.

[0153] Quality (QC) evaluation criteria: (1) Particle size D of encapsulated pigment in the test sample 50 A change of less than 5% is grade A, 5% to 10% is grade B, 10% to 20% is grade C, and more than 20% is NG (unqualified). (2) If the viscosity change of the test sample is less than 5%, it is grade A; 5%~10% is grade B; 10%~20% is grade C; and more than 20% is NG (failed); (3) If the filtration time of the treated test sample is less than 3 minutes, it is Class A; 3 minutes to 5 minutes is Class B; 5 minutes to 8 minutes is Class C; and more than 8 minutes is NG (unqualified).

[0154] The test results are shown in Table 1 below.

[0155] Table 1

[0156] The aqueous dispersions of Examples 1 to 7 were cross-linked and encapsulated with pigments, and the particle size change, viscosity change and filtration time of the test samples all reached Class B or above. This shows that the thermal desorption and cold precipitation of the dispersant were effectively suppressed in the dispersions cross-linked and encapsulated by the present invention, and the side reactants in the aqueous phase were also reduced.

[0157] The aqueous dispersion of Comparative Example 1 did not cross-link and encapsulate the pigment, and the test sample had severe thermal desorption and cold precipitation, and the particle size change increased significantly, which led to poor filtration stability.

[0158] The mass ratio of the anchoring monomer to the carboxylic acid monomer in the dispersant used in the aqueous dispersion of Comparative Example 2 is less than 4.5, the dispersant has poor anchoring ability, and the aging treatment causes the dispersant to thermally desorb or cold precipitate, which deteriorates the dispersion stability and filtration stability of the aqueous dispersion.

[0159] The aqueous dispersion of Comparative Example 3 uses a water-soluble coating agent, so that the dispersion contains too much side reaction products such as polymerized colloids of the dispersant and the coating agent, which leads to NG filtration time.

[0160] The theoretical acid value of the dispersant CD9 used in the aqueous dispersion of Comparative Example 4 is less than 70 mgKOH / g. The low acid value leads to poor solubility of the dispersant CD9, and the colorant encapsulation crosslinking degree is insufficient, which is prone to cold precipitation, resulting in poor dispersion stability at low temperatures, causing the dispersion particle size, viscosity stability and filtration time to be NG.

[0161] 2. Solvent resistance test (dispersion stability and filtration stability test). The test method and steps are as follows: Each aqueous dispersion was diluted with water to a diluted sample with a colorant concentration of 5wt%. 50 g of the diluted sample was mixed with 50 g of dipropylene glycol methyl ether to obtain a test sample, and the dispersant thermal desorption and cold precipitation tests were performed. The test sample was placed in a high temperature environment of 60°C for 8 h, cooled to room temperature for 4 h, and in a low temperature environment of -20°C for 8 h, and returned to room temperature for 4 h; the above steps were repeated for 7 days. The particle size and viscosity of the test sample before and after the treatment were tested, as well as the filtration time of the test sample after treatment. The detection method and quality evaluation criteria were the same as the aging test.

[0162] The test results are shown in Table 2 below.

[0163] Table 2

[0164] The particle size change, viscosity change and filtration time of the test samples of the aqueous dispersions of Examples 1 to 7 after crosslinking and encapsulating the pigment all reached Class B or above. This shows that the thermal desorption and cold precipitation of the dispersant are effectively suppressed in the dispersions after crosslinking and encapsulating the pigment, and the side reactants in the aqueous phase are also reduced.

[0165] In the test of strong solvent resistance, the particle size, viscosity and filtration time of the aqueous dispersions of Examples 1 to 7 after cross-linking and encapsulating the pigments were rated above Class B.

[0166] The aqueous dispersion of Comparative Example 1 did not cross-link and encapsulate the pigment, and was severely affected by competitive adsorption of the strong solvent, and the dispersion stability and filtration stability of the test sample were significantly deteriorated.

[0167] The mass ratio of the anchoring monomer to the carboxylic acid monomer in the dispersant used in the aqueous dispersion of Comparative Example 2 is less than 4.5, the dispersant has poor anchoring ability, the dispersant encapsulation on the surface of the colorant is incomplete, and it is easily desorbed by competitive strong solvents, resulting in poor dispersion stability and filtration stability.

[0168] The aqueous dispersion of Comparative Example 3 uses a water-soluble coating agent, so that the dispersion contains too many side reactants, which leads to a filtration time NG.

[0169] The theoretical acid value of the dispersant CD9 used in the aqueous dispersion of Comparative Example 4 is less than 70 mgKOH / g, the colorant encapsulation crosslinking degree is insufficient, the dispersant is easily desorbed under the action of strong solvents, and cold precipitation problems are prone to occur, resulting in the particle size, viscosity stability and filtration time of the aqueous dispersion being NG.

[0170] The embodiments of the present invention are described in detail above in conjunction with the embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. An encapsulated colorant, characterized in that: The encapsulated pigment comprises a pigment and a coating layer encapsulated on the surface of the pigment; the coating layer is prepared by cross-linking and curing a dispersant and a coating agent containing an epoxy group and an anchoring segment; The dispersant is obtained by reacting a carboxylic acid monomer and a hydrophobic anchor monomer; the amounts of the anchor monomer and the carboxylic acid monomer satisfy a theoretical acid value of 70 mgKOH / g to 176 mgKOH / g; Where, theoretical acid value = [56.1 / total weight of monomer]* *1000; 56.1 is the molecular weight of potassium hydroxide; total mass of monomers = the sum of the mass of monomers reacted in the dispersant; i An item representing a carboxylic acid-based monomer; M i Carboxylic acid monomer i The number of moles; A i Single carboxylic acid monomer i The average number of carboxylic acid groups; The solubility of the coating agent in water is less than 1 wt %.

2. The encapsulated colorant according to claim 1, characterized in that: The structure of the encapsulating agent is substituted R; wherein the number of substitutions is from single substitution to the maximum number of substitutions; the substitution is , , is replaced by at least one of; said R refers to an anchoring segment; Preferably, the R is selected from substituted or unsubstituted C6~C 20 Aliphatic hydrocarbons, substituted or unsubstituted C6~C 20 Aromatic ring, substituted or unsubstituted C3~C 20 Heterocyclic ring; Preferably, the R is selected from the following structural formula: 、 、 、 、 、 、 、 、 、 。 3. The encapsulated colorant according to claim 1, characterized in that: The solubility of the coating agent in water is not higher than 0.5wt%; And / or, the coating agent includes at least one of sorbitol glycidyl ether, hydrogenated bisphenol A diglycidyl ether, 1,6-hexanediol diglycidyl ether, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, 3,3'5,5'-tetramethylbiphenyl bisphenol diglycidyl ether, N,N,N,N,-tetraepoxypropyl-4,4-diaminodiphenylmethane, triglycidyl p-aminophenol, triglycidyl isocyanurate, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-2,2-bis[4-(4-aminophenoxy)phenyl]propane, N,N-di(glycidyl)aniline, and 1,2-cyclohexanedicarboxylic acid diglycidyl ester.

4. The encapsulated colorant according to claim 1, characterized in that: The preparation method of the dispersant comprises the following steps: In an inert gas atmosphere, a first mixture containing an anchoring group monomer, a carboxylic acid group monomer and an initiator is prepared and subjected to a polymerization reaction to obtain the dispersant.

5. The encapsulated colorant according to claim 4, characterized in that: The carboxylic acid monomer includes at least one of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, citraconic acid, 4-vinylbenzoic acid, β-(acryloyloxy)propionic acid, and methacryloyloxyethyl succinate; And / or, the mass ratio of the anchoring group monomer to the carboxylic acid group monomer is (4.5-9):1; and / or, the theoretical oil-water partition coefficient of the anchoring group monomer LogP≧2.0; And / or, the anchoring group monomer includes at least one of styrene and hydrophobic acrylate.

6. The encapsulated colorant according to claim 4, characterized in that: The first mixture further comprises at least one of a first solvent and a buffer monomer; Preferably, the buffer monomer includes at least one of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, etc.; Preferably, the mass ratio of the buffer monomer to the anchoring monomer is (0.1-0.5):

1.

7. The method for preparing the encapsulated colorant according to any one of claims 1 to 6, characterized in that: The following steps are involved: The second mixture containing the pigment and the dispersant is mixed with the coating agent to carry out a cross-linking reaction, thereby obtaining the encapsulated pigment.

8. The preparation method according to claim 7, characterized in that: The temperature of the cross-linking reaction is 50°C to 90°C; And / or, the cross-linking reaction time is 5 h to 20 h; And / or, the mass ratio of the colorant to the dispersant is 1:(0.125-3); And / or, the mass ratio of the colorant to the coating agent is 1:(0.0125~0.3).

9. A pigment dispersion, characterized in that: The colorant dispersion comprises the encapsulated colorant according to any one of claims 1 to 6 and optional auxiliary agents.

10. Use of the encapsulated colorant according to any one of claims 1 to 6 or the colorant dispersion according to claim 9 in coatings, printing inks, displays, textile printing or inkjet inks.

Images