Preparation and application of a high color yield self-dispersible nano organic pigment

Abstract

The invention discloses the preparation and application of a self-dispersible nano organic pigment with high color yield, and belongs to the technical field of fine chemicals. The method of the invention uses a reactive dye with both water solubility and high reactivity as a colorant, grafts it to the surface of nanoparticles containing multiple amino functional groups, and prepares a self-dispersible nano organic pigment with high color yield. The method of the invention solves the problem of low grafting rate of reactive dyes on the surface of nanoparticles, uses α-bromoacrylamide type reactive dyes as grafting agents, and performs surface grafting modification on amino polymethacrylate glyceride latex particles, and the grafting amount of the active dye on the surface of the prepared organic pigment reaches more than 25%, and under the condition of the same colorant dosage, the color yield of the pigment is significantly improved. At the same time, because the dye structure of the invention contains anionic groups, there is a strong electrostatic repulsion between adjacent particles, so it has good self-dispersibility.

Description

Technical Field

[0001] The invention relates to the preparation and application of a self-dispersed nano organic pigment with high color yield, belonging to the technical field of fine chemical industry. Background Art

[0002] Inkjet printing with organic pigment inks has the advantages of energy saving and high efficiency (only one step of color fixation is required), simple process (eliminating the steps of washing and drying), strong adaptability (no selectivity for substrates), etc., and has great development potential in the field of printing. However, conventional pigment ink printing has two characteristics: (1) Organic pigment particles exist in the ink in a particle state under the action of dispersants, and because they have no affinity for textiles, they need to be adhered to the surface of the fabric with the help of film-forming polymers. This physical fixation mechanism has certain weaknesses due to the lack of strong binding force between the colorant and the polymer. During the use process, the colorant particles are very easy to fall off at the defects of the color film under strong external mechanical forces (such as repeated friction, rubbing, etc.), resulting in poor friction resistance and water washing color fastness of the printed fabric. (2) The surface of organic pigment particles is inert. During storage, the dispersant is easily desorbed, causing particle agglomeration. During the spraying process, the nozzle is blocked, resulting in non-precise positioning spraying such as parallel lines, line breaks, oblique spraying and sputtering. Moreover, after film formation, it is easy to be exposed and accumulate on the surface of the film, which reduces the quality of inkjet printed fabrics.

[0003] Polymer dyes obtained by covalently anchoring organic dyes to polymer skeleton structures through covalent bonds are special organic pigments that have both the color and light absorption of dyes, as well as the film-forming and migration resistance of polymers. They are an effective way to achieve colorant-polymer integration. For example, the team of Professor Kan Chengyou of Tsinghua University, Professor Jiang Zhenhua of Jilin University, and Professor Wang Chaoxia of Jiangnan University used amino-, hydroxyl-, or carboxyl-containing chromophores to condense with polyphenylene sulfone, polyepoxy resin, and polyurethane monomers to prepare condensation-type polymer dyes. This type of dye matrix is ​​strongly covalently bonded to the polymer chain, which can significantly improve the color fastness of the polymer dye. However, due to the small particle size of polymer dye particles and the neutral surface, they are prone to agglomeration and have poor dispersion stability.

[0004] Grafting active dyes with both chromophores and water-soluble groups onto the surface of nanoparticles is one of the effective methods to simultaneously solve the above-mentioned poor fastness and poor stability. Among them, the film formation during the color fixation process of the polymer chain improves the fixation fastness of the organic pigment on the surface of the fabric, and the water-soluble groups in the structure of the active dye give the particles good stability. In addition, the chromophore gives the particles color properties. However, the applicant previously used dichloro-s-triazine-type active dyes to graft and modify nanoparticles to prepare a self-dispersing nano organic pigment. Then, the grafting rate of the active dye on the surface of the organic pigment is too low, resulting in too low color yield of the pigment when used for printing on fabrics, limiting its scope of application.

[0005] Therefore, there is an urgent market demand for preparing a self-dispersible nano-organic pigment with high color yield. Summary of the invention

[0006] [Technical issues]

[0007] Reactive dyes grafted onto nanoparticles can simultaneously solve the problems of poor stability and fastness of organic pigment inks. However, due to the low grafting rate of reactive dyes on the surface of nanoparticles, this type of pigment ink has a low color yield when used for fabric printing, which limits its scope of application.

[0008] [Technical solution]

[0009] In order to solve the above problems, the present invention uses α-bromoacrylamide type active dye as a grafting agent to carry out surface grafting modification on amino polymethacrylate glycerol latex particles, and the grafting amount of the prepared organic pigment surface active dye reaches more than 25%, and the color yield of the pigment is significantly improved under the same colorant dosage condition. At the same time, since the dye structure contains anionic groups, there is a strong electrostatic repulsion between adjacent particles, so it has good self-dispersion performance.

[0010] The first object of the present invention is to provide a method for preparing a self-dispersible nano organic pigment with high color yield, comprising the following steps:

[0011] (1) dissolving polyvinyl pyrrolidone in deionized water, adding glycidyl methacrylate, and emulsifying uniformly to form an emulsion; then adding an aqueous ammonium persulfate solution to the emulsion for reaction, cooling, centrifuging, collecting precipitates, washing, and drying to obtain polymethacrylate glycerol latex particles;

[0012] (2) adding the obtained polymethacrylate glycerol latex particles into deionized water and mixing them to obtain a polymethacrylate glycerol latex particle dispersion; slowly dropping the polyethyleneimine aqueous solution into the polymethacrylate glycerol latex particle dispersion to react at room temperature (20-30° C.); after the reaction is completed, centrifuging and collecting the precipitate, washing with water until the pH of the washing solution is neutral, and drying to obtain amino polymethacrylate glycerol latex particles;

[0013] (3) adding the obtained amino polymethacrylate glyceryl latex particles into deionized water and mixing them to obtain an amino polymethacrylate glyceryl latex particle dispersion; dissolving α-bromoacrylamide type reactive dye in deionized water to form a mixed solution; adding the mixed solution into the amino polymethacrylate glyceryl latex particle dispersion to react, and after the reaction is completed, cooling, centrifuging, collecting the precipitate, washing, and drying to obtain a high color yield self-dispersible nano organic pigment.

[0014] In one embodiment of the present invention, the mass ratio of polyvinyl pyrrolidone to glycidyl methacrylate in step (1) is (1-3):1. Specifically, it can be 1.5:1.

[0015] In one embodiment of the present invention, the mass ratio of glycidyl methacrylate to ammonium persulfate in step (1) is 1:(0.05-0.2). Specifically, it can be 1:0.08.

[0016] In one embodiment of the present invention, in step (1), specifically, the mass ratio of polyvinyl pyrrolidone, glycidyl methacrylate and ammonium persulfate is 3:2:0.16.

[0017] In one embodiment of the present invention, in step (1), the concentration of the aqueous ammonium persulfate solution is 0.1-0.3 g / mL, and specifically 0.16 g / mL.

[0018] In one embodiment of the present invention, in step (1), the concentration of polyvinyl pyrrolidone dissolved in deionized water is 0.1-1.0 g / mL; specifically, 0.3 g / mL may be selected.

[0019] In one embodiment of the present invention, the emulsification time in step (1) is 20 to 60 minutes, and the rotation speed is 500 to 1000 rpm.

[0020] In one embodiment of the present invention, the reaction temperature in step (1) is 60-90° C. and the reaction time is 3-6 hours.

[0021] In one embodiment of the present invention, in step (2), the concentration of the polymethacrylate glycerol latex particle dispersion is 0.1-0.5 g / mL.

[0022] In one embodiment of the present invention, in step (2), the mass ratio of polymethacrylate glycerol latex particles to polyethyleneimine is 1:(0.5-1.5), and specifically 1:0.6.

[0023] In one embodiment of the present invention, in step (2), the concentration of the polyethyleneimine aqueous solution is 0.5-1.0 g / mL; specifically, 0.6 g / mL may be selected.

[0024] In one embodiment of the present invention, in step (2), the Mn of the polyethyleneimine aqueous solution is 600-800.

[0025] In one embodiment of the present invention, the reaction time in step (2) is 6 to 10 hours.

[0026] In one embodiment of the present invention, the centrifugal conditions in step (2) are: rotation speed 10000-12000 rpm, time 25-60 min.

[0027] In one embodiment of the present invention, the concentration of the dispersion of amino polymethacrylate glycerol latex particles in step (3) is 0.1-0.5 g / mL.

[0028] In one embodiment of the present invention, the α-bromoacrylamide type reactive dye in step (3) includes any one or more of the following: CI Reactive Yellow 39, CI Reactive Blue 50 (Reactive Blue 3R), CI Reactive Red 136, CI Reactive Red 83, CI Reactive Red 84, CI Reactive Red 66, CI Reactive Red 116, CI Reactive Blue 69, and Reactive Navy Blue B.

[0029] In one embodiment of the present invention, the concentration of the α-bromoacrylamide type reactive dye in the mixed solution in step (3) is 0.03 g / mL.

[0030] In one embodiment of the present invention, in step (3), the mixed solution is added to the dispersion of amino polymethacrylate glycerol latex particles and the pH value of the system is adjusted to 5-7 with acetic acid / ammonium acetate buffer solution to carry out the reaction.

[0031] In one embodiment of the present invention, the reaction temperature in step (3) is 60 to 90° C. and the reaction time is 60 to 90 min.

[0032] In one embodiment of the present invention, the centrifugal conditions in step (3) are: rotation speed 10000-12000 rpm, time 5-30 min.

[0033] In one embodiment of the present invention, a method for self-dispersing nano organic pigments with high color yield specifically comprises the following steps:

[0034] (1) Preparation of polymethacrylate latex particles

[0035] Take a certain amount of polyvinyl pyrrolidone and dissolve it in deionized water, and add a certain amount of glycidyl methacrylate. After being emulsified evenly in an emulsifier, transfer it to a four-necked flask and heat it to a certain temperature under nitrogen protection; dissolve ammonium persulfate in deionized water and add it to the emulsion, and continue the reaction for a certain time; cool the product to room temperature, centrifuge it, wash the precipitate with alcohol and water; dry it in a freeze dryer for 48 hours to obtain polymethacrylate glycerol latex particle powder;

[0036] (2) Preparation of amino polymethacrylate latex particles

[0037] A certain amount of polymethacrylate glycerol latex particles is added into deionized water, and ultrasonic treatment is performed for a certain period of time to obtain a polymethacrylate glycerol latex particle dispersion; a certain amount of branched polyethyleneimine is dissolved in deionized water, and the dispersion is slowly added dropwise to the polymethacrylate glycerol latex particle dispersion, and the dispersion is reacted at room temperature for a certain period of time to obtain an amino polymethacrylate glycerol latex particle dispersion; the dispersion is centrifuged at a certain speed for a period of time, and the precipitate is washed with deionized water until the pH of the washing liquid is neutral; finally, the sample is placed in a freeze dryer and dried for 48 hours to obtain an amino polymethacrylate glycerol latex particle powder;

[0038] (3) Preparation of high color yield self-dispersible nano organic pigments

[0039] A certain amount of amino-polymethacrylate glyceryl latex particle powder is added into deionized water, and after ultrasonic treatment for a period of time, an amino-polymethacrylate glyceryl latex particle dispersion is obtained; α-bromoacrylamide type reactive dye is dissolved in deionized water and added into the amino-polymethacrylate glyceryl latex particle dispersion, and the pH value of the system is adjusted with acetic acid / ammonium acetate buffer solution, and the reaction is carried out for a certain time under certain temperature conditions; after the dispersion is cooled, it is centrifuged at a certain speed for a period of time, and the unreacted reactive dye is washed away with deionized water; finally, the precipitate is freeze-dried for 48 hours to obtain a high color yield self-dispersible nano organic pigment powder.

[0040] In one embodiment of the present invention, in step (1), the mass ratio of polyvinyl pyrrolidone, glycidyl methacrylate and ammonium persulfate is 3:2:0.16.

[0041] In one embodiment of the present invention, the mass / volume ratio of polyvinyl pyrrolidone to deionized water in step (1) is 30 g:100 mL.

[0042] In one embodiment of the present invention, the emulsification time in step (1) is 20 to 60 minutes, and the rotation speed is 500 to 1000 rpm.

[0043] In one embodiment of the present invention, the reaction temperature in step (1) is 60-90° C. and the reaction time is 3-6 hours.

[0044] In one embodiment of the present invention, the mass / volume ratio of polymethacrylate glycerol latex particles to deionized water in step (2) is 10 g:100 mL.

[0045] In one embodiment of the present invention, the ultrasonic time in step (1) is 25 to 60 minutes.

[0046] In one embodiment of the present invention, the mass / volume ratio of the branched polyethyleneimine to deionized water in step (2) is 6 g:10 mL, and the Mn of the branched polyethyleneimine is 600-800.

[0047] In one embodiment of the present invention, the reaction time in step (2) is 6 to 10 hours.

[0048] In one embodiment of the present invention, the centrifugal conditions of the dispersion in step (2) are: rotation speed 10000-12000 rpm, time 25-60 min.

[0049] In one embodiment of the present invention, in step (3), the mass / volume ratio of the amino polymethacrylate glycerol latex particle powder to deionized water is 10 g:100 mL.

[0050] In one embodiment of the present invention, the ultrasonic time in step (3) is 25 to 60 minutes.

[0051] In one embodiment of the present invention, the α-bromoacrylamide type reactive dye in step (3) can be one of CI Reactive Yellow 39, CI Reactive Blue 50 (Reactive Blue 3R), CI Reactive Red 136, CI Reactive Red 83, CI Reactive Red 84, CI Reactive Red 66, CI Reactive Red 116, CI Reactive Blue 69, Reactive Navy Blue B

[0052] In one embodiment of the present invention, the mass / volume ratio of α-bromoacrylamide reactive dye to deionized water in step (3) is 3 g:100 mL.

[0053] In one embodiment of the present invention, the pH of the reaction solution in step (3) is 5-7, which is adjusted using acetic acid / ammonium acetate buffer solution.

[0054] In one embodiment of the present invention, the reaction temperature in step (3) is 60-90° C., and the reaction time is 60-90 min.

[0055] In one embodiment of the present invention, the centrifugal conditions of the dispersion in step (3) are: rotation speed 10000-12000 rpm, time 5-30 min.

[0056] The second object of the present invention is to provide a self-dispersible nano organic pigment with high color yield based on the above method.

[0057] The third object of the present invention is to use the high color yield self-dispersible nano organic pigments of the present invention in textile inkjet printing.

[0058] In one embodiment of the present invention, the textile comprises cotton, linen, silk, wool, polyester, nylon, acrylic or a plurality of blended fibers and fabrics thereof.

[0059] [Beneficial Effects]

[0060] The active dye grafting rate in the self-dispersible nano organic pigment structure of the present invention can reach more than 25%, which solves the problem of low color yield (<10%) of the existing nano self-dispersible dyes and can achieve the effect of high color yield.

[0061] Specifically, the method of the present invention uses a reactive dye with both water solubility and high reactivity as a colorant, grafts it onto the surface of nanoparticles containing multiple amino functional groups, and prepares a self-dispersible nano organic pigment with high color yield. The method of the present invention solves the problem of low grafting rate of reactive dyes on the surface of nanoparticles. Using α-bromoacrylamide type reactive dyes as grafting agents, surface grafting modification is performed on amino polymethacrylate glyceride latex particles, and the grafting amount of the reactive dye on the surface of the prepared organic pigment reaches more than 25%. Under the condition of the same colorant dosage, the color yield of the pigment is significantly improved. At the same time, because the dye structure of the present invention contains anionic groups, there is a strong electrostatic repulsion between adjacent particles, so it has good self-dispersibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 This is the Fourier infrared spectrum of the high color yield self-dispersible nano organic pigment obtained in Example 1.

[0063] Figure 2 : This is the Fourier infrared spectra of PGMA and PGMA-NH2 in Example 1.

[0064] Figure 3 This is the thermogravimetric analysis diagram of PGMA.

[0065] Figure 4 This is the thermogravimetric analysis diagram of PGMA-NH2.

[0066] Figure 5 This is the thermogravimetric analysis diagram of the high color yield self-dispersible nano organic pigment obtained in Example 1.

[0067] Figure 6 This is the thermogravimetric analysis diagram of the high color yield self-dispersible nano organic pigment obtained in Example 2.

[0068] Figure 7 This is the thermogravimetric analysis diagram of the pigment obtained in Comparative Example 1.

[0069] Figure 8 This is the thermogravimetric analysis diagram of the pigment obtained in Comparative Example 2. DETAILED DESCRIPTION

[0070] The preferred embodiments of the present invention are described below. It should be understood that the embodiments are for better explaining the present invention and are not used to limit the present invention.

[0071] K / S value characterization: The apparent color depth (apparent color yield) of printed fabrics can be measured and represented by the K / S value of printed fabrics. According to the Kubelka-Munk law, it is as follows:

[0072] K / S=(1-R) 2 / 2R

[0073] Where: K is the absorption coefficient; S is the scattering coefficient; R is the value of the light when it is not transmitted. max The reflectivity below.

[0074] The present invention adopts the TG method to test the grafting rate of the active dye on the surface of the nanoparticle.

[0075] Viscosity: The ink sample was dropped onto the sample stage of a rotational rheometer (RheoWin MADS 60) at 25°C and a shear rate of 200 s. -1 The viscosity of the sample was measured under the conditions of 3 times and the average value was taken.

[0076] Surface tension: 50 mL of ink sample was placed in a beaker. A dynamic surface tension meter (BP100) was used to test the dynamic surface tension of the sample at 25°C. The test time was 20,000 ms and the range was 10-100 mN / m.

[0077] pH value: Use a pH meter model ST3100 to test the pH value of the sample at 25°C. Measure each sample three times and take the average value.

[0078] Particle size and Zeta potential: After diluting the sample, a particle size tester (Nano-ZS90) was used to measure the particle size and Zeta potential of the sample. Each sample was measured three times and the average value was taken.

[0079] The raw materials involved in the present invention are as follows:

[0080]

[0081] Example 1

[0082] A method for preparing a high-color-yield self-dispersible nano organic pigment comprises the following steps:

[0083] (1) Preparation of polymethacrylate latex particles (PGMA)

[0084] Take 30g of polyvinyl pyrrolidone and dissolve it in 100mL of deionized water, and add 20g of glycidyl methacrylate. After emulsification in an emulsifier (speed is 600rpm) for 30min, transfer it to a four-necked flask and heat it to 75°C under nitrogen protection. Dissolve 1.6g of ammonium persulfate in 10mL of deionized water and add it to the emulsion, and continue the reaction for 5h. Cool the product to room temperature, centrifuge it at 10000rpm, wash the precipitate with alcohol, and wash it with water. After drying in a freeze dryer for 48h, obtain polymethacrylate glycerol latex particle powder.

[0085] (2) Preparation of amino polymethacrylate latex particles (PGMA-NH2)

[0086] Add 10g of polymethacrylate glycerol latex particles into 100mL of deionized water, and treat with ultrasound for 30min to obtain a polymethacrylate glycerol latex particle dispersion. Dissolve 6g of branched polyethyleneimine (Mn=600-800) into 10mL of deionized water, and slowly add it dropwise to the polymethacrylate glycerol latex particle dispersion. After reacting at room temperature for 8h, an amino polymethacrylate glycerol latex particle dispersion is obtained. Centrifuge the dispersion at 12000rpm for 30min, and wash the precipitate with deionized water until the pH of the washing liquid is neutral. Finally, place the sample in a freeze dryer and dry it for 48h to obtain an amino polymethacrylate glycerol latex particle powder.

[0087] (3) Preparation of high color yield self-dispersible nano organic pigment (PGMA-NH-PW-4G)

[0088] 10g of amino polymethacrylate glycerol latex particle powder was added to 100mL of deionized water, and after ultrasonic treatment for 30min, an amino polymethacrylate glycerol latex particle dispersion was obtained. 3g of CI Reactive Yellow 39 was dissolved in 100mL of deionized water and added to the amino polymethacrylate glycerol latex particle dispersion. The pH of the system was adjusted to 6.5 with acetic acid / ammonium acetate buffer solution, and the reaction was kept at 85°C for 70min. After the dispersion was cooled, it was centrifuged at 10000rpm for 10min, and the unreacted active dye was washed away with deionized water. Finally, the precipitate was freeze-dried for 48h to obtain a high color yield self-dispersible nano organic pigment powder.

[0089] The purified Example 1 ( Figure 1 ) The product was characterized by Fourier transform infrared spectroscopy. Compared with PGMA and PGMA-NH2 ( Figure 2 ), there is an additional absorption peak at 1690 cm-1 in the structure of Example 1, which is the stretching vibration peak of the carbonyl group in the amide group, indicating that the α-bromoacrylamide type reactive dye is successfully grafted into the amino polymethacrylate latex particle structure.

[0090] Example 2

[0091] A method for preparing a high-color-yield self-dispersible nano organic pigment comprises the following steps:

[0092] (1) Preparation of polymethacrylate latex particles (PGMA)

[0093] Same as Example 1.

[0094] (2) Preparation of amino polymethacrylate latex particles (PGMA-NH2)

[0095] Same as Example 1.

[0096] (3) Preparation of high color yield self-dispersible nano organic pigment (PGMA-NH-PW-3R)

[0097] 10g of amino polymethacrylate glycerol latex particle powder was added to 100mL of deionized water, and after ultrasonic treatment for 30min, an amino polymethacrylate glycerol latex particle dispersion was obtained. 3g of reactive blue 3R (CI reactive blue 50) was dissolved in 100mL of deionized water and added to the amino polymethacrylate glycerol latex particle dispersion. The pH of the system was adjusted to 6.5 with acetic acid / ammonium acetate buffer solution, and the reaction was kept at 85°C for 70min. After the dispersion was cooled, it was centrifuged at 10000rpm for 10min, and the unreacted reactive dye was washed away with deionized water. Finally, the precipitate was freeze-dried for 48h to obtain a high color yield self-dispersible nano organic pigment powder.

[0098] Comparative Example 1

[0099] A method for preparing nano organic pigments comprises the following steps:

[0100] (1) Preparation of polymethacrylate latex particles (PGMA)

[0101] Same as Example 1.

[0102] (2) Preparation of amino PGMA latex particles (PGMA-NH2)

[0103] Same as Example 1.

[0104] (3) Preparation of self-dispersed colored latex particles (PGMA-NH-X-3B)

[0105] 10g of PGMA-NH2 was added to deionized water (100mL), and after ultrasonic treatment for 30min, a PGMA-NH2 latex particle dispersion was obtained. 3g of reactive red X-3B dye was dissolved in 100mL of deionized water and added to the PGMA-NH2 latex particle dispersion. The pH of the system was adjusted to 9-10 with NaCO3, and the reaction was kept at 40°C for 2h. After the dispersion was cooled, it was centrifuged at 10000rpm for 10min, and the unreacted reactive dye was washed away with deionized water. Finally, the precipitate was freeze-dried for 48h to obtain PGMA-NH-X-3B powder.

[0106] Comparative Example 2

[0107] A method for preparing nano organic pigments comprises the following steps:

[0108] (1) Preparation of polymethacrylate latex particles (PGMA)

[0109] Same as Example 1.

[0110] (2) Preparation of amino PGMA latex particles (PGMA-NH2)

[0111] Same as Example 1.

[0112] (3) Preparation of self-dispersed colored latex particles (PGMA-NH-KN-G)

[0113] Add 10g of PGMA-NH2 to deionized water (100mL), and after ultrasonic treatment for 30min, obtain a PGMA-NH2 latex particle dispersion. Dissolve 3g of active golden yellow KN-G dye in 100mL of deionized water, add it to the PGMA-NH2 latex particle dispersion, adjust the pH of the system to 9-10 with NaCO3, and react at 40℃ for 2h. After the dispersion is cooled, centrifuge at 10000rpm for 10min, and wash away the unreacted active dye with deionized water. Finally, freeze-dry the precipitate for 48h to obtain PGMA-NH-KN-G powder.

[0114] Grafting rate determination:

[0115] PGMA( Figure 3 )、PGMA-NH2( Figure 4 ), Example 1 after purification ( Figure 5 )、Example 2( Figure 6 ), Comparative Example 1( Figure 7 ), Comparative Example 2( Figure 8 )The content of grafted reactive dye in the structure of the product was characterized by thermogravimetric analysis.

[0116] Depend on Figure 3 and Figure 4It can be seen that both PGMA and PGMA-NH2 thermally decomposed at 378°C and 457°C. The mass loss at 378°C was mainly caused by the breakage of the polymer skeleton, and the mass loss at 457°C was mainly caused by the decomposition of a large number of ester bonds in the copolymer. After the temperature rose to 700°C, the mass loss of PGMA was close to 100%, while PGMA-NH2 had a mass residue of 5.28%, indicating that the grafting rate of PEI was 5.28%.

[0117] Depend on Figure 5 It can be seen that for the reactive dye CI Reactive Yellow 39 used in Example 1, when the temperature rises to 700°C, only about 30% of the mass loss occurs. This is because the reactive dye is a water-soluble dye and a large amount of bound water is adsorbed in the molecule. This part of the mass loss should be caused by the evaporation of the bound water in the molecule. After the temperature rises to 700°C, the product of Example 1 has a mass residue of 32.73%-5.28%=27.45%, indicating that the grafting rate of the reactive dye is 27.45%.

[0118] Depend on Figure 6 It can be seen that for the reactive dye Reactive Blue 3R used in Example 1, when the temperature rises to 700°C, only about 32% of the mass loss occurs. This is because the reactive dye is a water-soluble dye and a large amount of bound water is adsorbed in the molecule. This part of the mass loss should be caused by the evaporation of the bound water in the molecule. After the temperature rises to 700°C, the product of Example 1 has a mass residue of 35.66%-5.28%=30.38%, indicating that the grafting rate of the reactive dye is 30.38%.

[0119] Depend on Figure 7 It can be seen that for the reactive dye red X-3B used in comparative example 1, when the temperature rises to 700°C, only 26% of the mass loss occurs. This is because the reactive dye is a water-soluble dye and a large amount of bound water is adsorbed in the molecule. This part of the mass loss should be caused by the evaporation of the bound water in the molecule. After the temperature rises to 700°C, PGMA-NH-X-3B has a mass residue of 10.82%-5.28%=5.54%, indicating that the grafting rate of the reactive dye is 5.54%.

[0120] Depend on Figure 8 It can be seen that for the reactive yellow KN-G used in comparative example 1, when the temperature rises to 700°C, only 22% of the mass loss occurs. This is because the reactive dye is a water-soluble dye and a large amount of bound water is adsorbed in the molecule. This part of the mass loss should be caused by the evaporation of the bound water in the molecule. The product of comparative example 2 has a mass residue of 8.48%-5.28%=3.20% after the temperature rises to 700°C, indicating that the grafting rate of the reactive dye is 3.20%.

[0121] It can be concluded from the summary that the grafting rate of the surface active dye of the self-dispersible nano organic pigment prepared in Example 1 and Example 2 is much higher than that of Comparative Example 1 and Comparative Example 2.

[0122] Apply the above pigments for printing:

[0123] The nano organic pigments prepared in Example 1, Example 2, Comparative Example 1 and Comparative Example 2 are used to prepare organic pigment inks, and the formula is:

[0124] 30 g of 1,2-propylene glycol, diethylene glycol and ethylene glycol (wherein the mass ratio of 1,2-propylene glycol: diethylene glycol: ethylene glycol is 2:1:1), 40 g of a nano-organic pigment aqueous dispersion with a solid content of 10% (4 g of nano-organic pigment), 0.5 g of a defoamer T-118 and 1 g of a surfactant S-465 were mixed together, the pH value was adjusted between 7 and 8, and finally the volume was made up to 100 g with deionized water. After the mixture was stirred evenly, it was filtered through a PVDF filter membrane with an absolute pore size of 1 μm to prepare a self-dispersed nano-pigment ink with high color yield.

[0125] The physical and chemical properties of the prepared ink are shown in Table 1.

[0126] Table 1

[0127]

[0128]

[0129] The prepared ink was used to print the same color block using a Mimaki JV33 fifth-generation nozzle inkjet printer, and the printed color data is shown in Table 2.

[0130] Table 2

[0131] K / S value Example 1 7.56 Example 2 7.21 Comparative Example 1 2.98 Comparative Example 2 2.63

[0132] It can be seen from Table 1 that under the condition of the same amount of colorant, the color yield of the printed cotton fabrics of Example 1 and Example 2 is much higher than that of Comparative Example 1 and Comparative Example 2.

[0133] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for preparing a self-dispersible nano organic pigment with high color yield, characterized in that: The steps include: (1) dissolving polyvinyl pyrrolidone in deionized water, adding glycidyl methacrylate, and emulsifying uniformly to form an emulsion; then adding an aqueous ammonium persulfate solution to the emulsion for reaction, cooling, centrifuging, collecting precipitates, washing, and drying to obtain polymethacrylate glycerol latex particles; (2) adding the obtained polymethacrylate glycerol latex particles into deionized water and mixing them to obtain a polymethacrylate glycerol latex particle dispersion; slowly dropping the polyethyleneimine aqueous solution into the polymethacrylate glycerol latex particle dispersion to react at room temperature; after the reaction is completed, centrifuging and collecting the precipitate, washing with water until the pH of the washing solution is neutral, and drying to obtain amino polymethacrylate glycerol latex particles; (3) adding the obtained amino polymethacrylate glyceryl latex particles into deionized water and mixing them to obtain an amino polymethacrylate glyceryl latex particle dispersion; dissolving an α-bromoacrylamide type reactive dye in deionized water to form a mixed solution; adding the mixed solution into the amino polymethacrylate glyceryl latex particle dispersion, and then adjusting the pH value of the system to 5-7 with an acetic acid / ammonium acetate buffer solution to react, and after the reaction is completed, cooling, centrifuging, collecting the precipitate, washing, and drying to obtain a high color yield self-dispersible nano organic pigment, wherein the grafting amount reaches more than 25%; In step (3), the α-bromoacrylamide type reactive dye includes any one or more of the following: CI Reactive Yellow 39, CI Reactive Blue 50, CI Reactive Red 136, CI Reactive Red 83, CI Reactive Red 84, CI Reactive Red 66, CI Reactive Red 116, CI Reactive Blue 69, and Reactive Navy Blue B.

2. The method according to claim 1, characterized in that In step (1), the mass ratio of polyvinyl pyrrolidone to glycidyl methacrylate is (1-3):

1.

3. The method according to claim 1, characterized in that In step (1), the mass ratio of glycidyl methacrylate to ammonium persulfate is 1:(0.05-0.2).

4. The method according to claim 1, characterized in that: In step (2), the concentration of the polymethacrylate glycerol latex particle dispersion is 0.1-0.5 g / mL.

5. The method according to claim 1, characterized in that In step (2), the mass ratio of polymethacrylate glycerol latex particles to polyethyleneimine is 1:(0.5-1.5).

6. The method according to claim 1, characterized in that The concentration of the amino polymethacrylate glycerol latex particle dispersion in step (3) is 0.1-0.5 g / mL.

7. A high color yield self-dispersible nano organic pigment prepared by the method according to any one of claims 1 to 6.

8. Use of the high color yield self-dispersible nano organic pigment according to claim 7 in textile inkjet printing.

Images