Reactive dye ink for digital inkjet printing and preparation method thereof

Abstract

The invention discloses a preparation method of reactive dye ink for digital inkjet printing. The preparation method comprises the following steps: (1) adding distilled water, methacryloyloxyethyl trimethyl ammonium chloride and a glycidyl methacrylate monomer; (2) adding a styrene monomer, heating, and adding a 2, 2 '-azobis (isobutylamidine hydrochloride) solution; (3) preparing a reactive dye solution with the concentration of 80 to 120 mmol / L; (4) preparing a reactive polymer microsphere dispersion liquid with the concentration of 16-24 g / L; (5) slowly dropwise adding the reactive dye solution into the reactive polymer microsphere dispersion liquid to prepare a reactive dye / polymer composite microsphere dispersion liquid; (6) preparing a coupling component / water mixed solution; (7) adding the reactive dye / polymer composite microsphere dispersion liquid into the coupling component / water mixed solution; and (8) stirring and standing. The reactive dye ink printing process can be effectively shortened, the energy consumption and the water consumption are reduced, and the utilization efficiency and the color fastness of the reactive dye ink are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of ink for inkjet printing, and in particular relates to a reactive dye ink for digital inkjet printing and a preparation method thereof. Background Art

[0002] Inkjet printing technology is a new printing method. It abandons the complex process of plate making in traditional printing and prints directly on fabrics, which improves the printing precision and realizes small-batch, multi-variety, and multi-color printing. It also solves the problems of large footprint and serious pollution of traditional printing, so it has broad development prospects. Therefore, the gradual transformation of traditional printing and dyeing technology to digital printing technology is the general trend of the current textile industry. Compared with traditional printing and dyeing technology, digital printing technology is energy-saving and environmentally friendly, with low pollution emissions, and on the other hand, it does not require plate making, has a short delivery cycle, and has lower production costs in small batches. On the basis of meeting the underlying business logic of the textile industry, it is also in line with the current development direction of green environmental protection.

[0003] Although inkjet printing technology has solved many problems existing in traditional printing technology, there are still some defects. For example, at present, there are not many pigment inks used for textile inkjet printing. The ink used is mainly reactive dye ink. Reactive dye ink for cellulose fabric is easy to hydrolyze, and the color fixation process is easily affected by processing conditions such as temperature, humidity, and time. Therefore, there are problems such as long printing process, low dye utilization rate, long steaming time, and large discharge of colored wastewater in the application process. In order to solve the above problems, domestic and foreign research mainly focuses on the optimization of reactive dye ink formula and fabric pretreatment. For example, CN202311566537.X discloses a method for inkjet printing of cellulose fabrics with low energy consumption and high quality, which mainly sprays the fabric after reactive dye inkjet printing with an aqueous solution of a cross-linking reaction type color fixer, and then sprays the composite aqueous solution of a friction fastness enhancer and a softener, thereby achieving the color fixation of reactive dye ink. CN202210474505.6 discloses an environmentally friendly reactive dye ink and its application. The ink includes a reactive dye containing at least two reactive structures and coupling components such as a naphthalene ring and / or a multi-mesh metal ring, which can strengthen the binding effect between the dye and the printing carrier, thereby effectively reducing sewage discharge and being environmentally friendly. CN202011539481.5 A reactive dye ink suitable for high-speed inkjet printing and a preparation method thereof. The ink includes a compound surfactant and a moisturizing agent acetone acetal, has good printing performance under high-speed printing conditions, is not prone to infiltration, and also has good standby performance.

[0004] It can be seen from the above-mentioned inkjet printing technology that the existing inkjet printing technology mainly focuses on shortening the reactive dye inkjet printing process and improving the inkjet performance of the ink, and has not completely solved the problems of low dye utilization and large amount of colored wastewater caused by the hydrolysis of reactive dyes, and there are no clear reports on the innovation of reactive dye structure morphology and the strengthening of the interaction between reactive dyes and fibers. Therefore, how to solve the difficulties of the existing reactive dye ink printing process, the low dye utilization rate, reduce the energy and water consumption in the evaporation and washing process after inkjet printing of cotton fabrics, and improve the utilization efficiency and color fastness of reactive dye inks has become a difficult problem that technicians in the field of digital inkjet printing need to solve urgently. Summary of the invention

[0005] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a reactive dye ink for digital inkjet printing and a preparation method thereof, which can effectively shorten the reactive dye ink printing process, reduce energy consumption and water consumption, and improve the utilization efficiency and color fastness of the reactive dye ink.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for preparing reactive dye ink for digital inkjet printing, comprising the following steps:

[0007] 1. Preparation of reactive polymer microsphere dispersion:

[0008] (1) Add a certain amount of distilled water to a reaction container, add 0.01-0.04 mol / L of methacryloyloxyethyl trimethyl ammonium chloride and 0.06-0.1 mol / L of glycidyl methacrylate monomer in sequence, stir for a certain period of time, and set aside;

[0009] (2) adding 0.6-1.41 g / L of styrene monomer, stirring thoroughly, heating from room temperature to 70-90° C., adding 0.002-0.006 g / L of 2,2'-azobisisobutylamidine hydrochloride solution, reacting at constant temperature for 2-6 hours, and cooling to room temperature to obtain a reactive polymer microsphere dispersion;

[0010] 2. Preparation of reactive dye / polymer composite microsphere dispersion:

[0011] (3) Prepare a reactive dye solution with a concentration of 80-120 mmol / L for standby use;

[0012] (4) preparing the reactive polymer microsphere dispersion prepared in step (2) into a reactive polymer microsphere dispersion having a concentration of 16-24 g / L;

[0013] (5) under stirring conditions, slowly adding the active dye solution prepared in step (3) to the reactive polymer microsphere dispersion prepared in step (4) at a certain volume ratio, and continuously stirring for 1 hour to obtain an active dye / polymer composite microsphere dispersion;

[0014] 3. Preparation of reactive dye / polymer composite microsphere ink:

[0015] (6) Prepare a coupling component / water mixed solution with a concentration of 2-10 wt% for standby use;

[0016] (7) adding the prepared reactive dye / polymer composite microsphere dispersion to the coupling component / water mixed solution;

[0017] (8) Mechanically stir at room temperature for 6-24 hours, and then let stand for 12-48 hours to obtain a reactive dye ink.

[0018] In the above-mentioned method for preparing reactive dye ink for digital inkjet printing, in the step (1), the concentration of methacryloyloxyethyltrimethylammonium chloride is 0.02 mol / L, and the concentration of glycidyl methacrylate monomer is 0.08 mol / L.

[0019] In the above-mentioned method for preparing reactive dye ink for digital inkjet printing, in the step (2), the mass fraction of styrene monomer is 1 g / L, after sufficient stirring, the temperature is raised from room temperature to 80°C, 0.004 g / L of 2,2'-azobisisobutylamidine hydrochloride solution is added, and the reaction is carried out at a constant temperature for 4 hours.

[0020] The above-mentioned method for preparing reactive dye ink for digital inkjet printing, in the step (3), the reactive dye solution is prepared by mixing reactive dye and deionized water, and the concentration is 100 mmol / L, wherein the reactive dye is any one or more of CI Reactive Red 218, CI Reactive Red 24, CI Reactive Blue 72, CI Reactive Blue 15, CI Reactive Blue 49, CI Reactive Orange 13, CI Reactive Black 5, and CI Reactive Black 8.

[0021] In the above-mentioned method for preparing reactive dye ink for digital inkjet printing, in the step (4), the concentration of the reactive polymer microsphere dispersion is 20 g / L.

[0022] In the above-mentioned method for preparing reactive dye ink for digital inkjet printing, in the step (5), the volume ratio of the reactive dye solution to the reactive polymer microsphere dispersion is 1:0.5-1:3, and the dripping rate is 0.3 L / h.

[0023] In the above-mentioned method for preparing reactive dye ink for digital inkjet printing, in the step (6), the concentration of the coupling component / water mixed solution is 6 wt %.

[0024] In the above-mentioned method for preparing reactive dye ink for digital inkjet printing, in the step (6), the coupling component is a water-soluble solvent containing hydroxyl or amino groups that can couple with the reactive dye / polymer composite microspheres by hydrogen bonds or hydrophobic forces, including one or a combination of glycerol, 1,2-propylene glycol, ethylene glycol, diethylene glycol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol 200, polyethylene glycol 400, triethanolamine, ethylenediamine, and nitrilotriacetic acid.

[0025] A reactive dye ink for digital inkjet printing is prepared by the above preparation method.

[0026] The above-mentioned reactive dye ink for digital inkjet printing has a viscosity of 3-10 mPa·s and a surface tension of 30-50 mN / m.

[0027] The advantages of the preparation method of the reactive dye ink for digital inkjet printing and the preparation method thereof of the present invention are: the present invention uses reactive polymer microspheres as a matrix to prepare reactive dyes / polymer microspheres, and establishes multiple interactions between dye molecules and cellulose fibers by means of reactive groups and self-crosslinking on the surface thereof, and completely fixes the hydrolyzed reactive dyes and unhydrolyzed reactive dyes on the fabric surface, effectively improving the utilization efficiency and color fastness of the dye ink. Since dye ink is the most demanded ink variety in the textile inkjet printing ink market, accounting for more than 90%, the present invention solves the difficulties of the current reactive dye ink printing process being long and the dye utilization rate being low, reduces the energy and water consumption in the evaporation and washing process after the cotton fabric inkjet printing, improves the color depth of the dyeing, and promotes the green and efficient inkjet printing of cotton fabrics, and therefore has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the self-crosslinking of the self-crosslinkable reactive dye / polymer composite microspheres in the reactive dye ink of the present invention and the reaction with the cellulose fibers;

[0029] Figure 2 This is an electron microscope photo of the polymer film structure formed by the self-crosslinked polymer microspheres on the surface of cellulose fibers;

[0030] Figure 3 The product physical pictures of reactive dye inks of different colors prepared by the preparation method of the present invention are as follows;

[0031] Figure 4 This is a transmission electron microscope picture of the active dye / polymer composite microsphere with a core-shell structure of the present invention;

[0032] Figure 5 The electron microscope images are comparative morphologies of the cotton fabric surface after inkjet printing with common dye ink and the reactive dye ink of the present invention;

[0033] Figure 6 A comparison diagram of the pattern printing effects of ordinary dye ink and the reactive dye ink of the present invention at the same dye concentration. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] In the present invention, unless otherwise stated, directional words such as "upper" and "lower" generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the attached drawings; while "inside" and "outside" refer to the outline of the device. In addition, in the description of this application, the term "including" means "including but not limited to". The terms first, second, third, etc. are used only as labels and do not impose numerical requirements or establish an order. The term "plurality" means "two or more".

[0036] A method for preparing reactive dye ink for digital inkjet printing, characterized in that it comprises the following steps:

[0037] 1. Preparation of reactive polymer microsphere dispersion:

[0038] (1) Add a certain amount of distilled water to a reaction container, add 0.01-0.04 mol / L of methacryloyloxyethyl trimethyl ammonium chloride and 0.06-0.1 mol / L of glycidyl methacrylate monomer in sequence, stir for a certain period of time, and set aside;

[0039] (2) adding 0.6-1.41 g / L of styrene monomer, stirring thoroughly, heating from room temperature to 70-90° C., adding 0.002-0.006 g / L of 2,2'-azobisisobutylamidine hydrochloride solution, reacting at constant temperature for 2-6 hours, and cooling to room temperature to obtain a reactive polymer microsphere dispersion;

[0040] 2. Preparation of reactive dye / polymer composite microsphere dispersion:

[0041] (3) Prepare a reactive dye solution with a concentration of 80-120 mmol / L for standby use;

[0042] (4) preparing the reactive polymer microsphere dispersion prepared in step (2) into a reactive polymer microsphere dispersion having a concentration of 16-24 g / L;

[0043] (5) under stirring conditions, slowly dropwise adding the active dye solution obtained in step (1) into the reactive polymer microsphere dispersion at a certain volume ratio, and continuously stirring for 1 hour to obtain an active dye / polymer composite microsphere dispersion;

[0044] 3. Preparation of reactive dye / polymer composite microsphere ink:

[0045] (6) Prepare a coupling component / water mixed solution with a concentration of 2-10 wt% for standby use;

[0046] (7) adding the prepared reactive dye / polymer composite microsphere dispersion to the coupling component / water mixed solution;

[0047] (8) Mechanically stir at room temperature for 6-24 hours, and then let stand for 12-48 hours to obtain a reactive dye ink.

[0048] The reactive dye solution is formed by mixing reactive dye and deionized water, and the concentration is 100mmol / L, wherein the reactive dye is any one or more of CI Reactive Red 218, CI Reactive Red 24, CI Reactive Blue 72, CI Reactive Blue 15, CI Reactive Blue 49, CI Reactive Orange 13, CI Reactive Black 5, and CI Reactive Black 8. The coupling component is a water-soluble solvent containing hydroxyl or amino groups that can couple with the reactive dye / polymer composite microspheres by hydrogen bonds or hydrophobic forces, including glycerol, 1,2-propylene glycol, ethylene glycol, diethylene glycol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol 200, polyethylene glycol 400, triethanolamine, ethylenediamine, and nitrilotriacetic acid. The viscosity of the reactive dye ink finally obtained is 3-10mPa·s, and the surface tension is 30-50mN / m.

[0049] In the prepared reactive polymer microsphere dispersion, the polymer microsphere is a micron-sized particle with a core-shell structure prepared by emulsion polymerization, the core layer is polymerized by any one or two of styrene, butyl acrylate, methyl methacrylate, and glycidyl methacrylate, and the shell layer is polymerized by any one or two of methacryloyloxyethyl trimethyl ammonium chloride and benzyl trimethyl ammonium chloride. In the prepared reactive dye / polymer composite microsphere dispersion, the surface of the reactive dye / polymer composite microsphere has 1-3 reactive groups such as carboxyl, hydroxyl, amino, epoxy, quaternary ammonium salt, and monochloro-s-triazine. The dye / polymer composite microsphere is an aggregate of dye and polymer microsphere, and the dye is fixed to the surface or the inside of the shell of the polymer microsphere by covalent bonds, ionic bonds, hydrogen bonds or hydrophobic forces. The ink components include reactive dye / polymer composite microspheres, coupling components and water, and can form a covalent cross-linked structure with hydroxyl and amino groups on the surface of cellulose fabrics and protein fabrics during heating at 70-180°C without any other treatment, and produce a stable and durable colored coating covering the fiber surface. The reactive dye ink prepared by the invention is mainly used in piezoelectric on-demand inkjet nozzles.

[0050] like Figure 1 , 2 As shown, there are multiple stable interactions between the self-crosslinkable reactive dye / polymer microspheres in the reactive dye ink of the present invention and the cellulose fiber. First, the self-crosslinking monomer in the reactive polymer structure provides active groups such as epoxy groups on the polymer microsphere surface, which can form covalent bonds with the hydroxyl groups on the cellulose fabric. Then, the quaternary ammonium salt group on the microsphere can be electrostatically bonded with the hydroxyl groups on the cellulose fiber. The third, the monochloro-s-triazine group from the reactive dye can also react with the remaining hydroxyl groups on the lyocell fabric to form covalent bonds. This shows that after the self-crosslinkable reactive dye / polymer microspheres are used for inkjet printing, after baking, they can form multiple interactions with the cellulose fiber, and the epoxy groups on the polymer microspheres give themselves efficient self-crosslinking properties, which can form a dense polymer film on the fiber surface and adhere to the fiber surface.

[0051] like Figure 3 As shown, reactive dye inks of different colors obtained by the preparation method of the present invention are shown, wherein: Figure 3 (a) is white, Figure 3 (b) is orange, Figure 3 (c) is magenta, Figure 3 (d) is yellow, Figure 3 (e) is turquoise blue. As can be seen from the figure, the prepared composite microsphere ink has bright color, high stability, and strong hiding power, which meets the requirements of coloring materials in ink and can also be produced in different colors according to actual printing needs.

[0052] The present application is described in detail below through specific embodiments. The following embodiments are only partial embodiments of the present application and are not limitations of the present application.

[0053] Embodiment 1:

[0054] A method for preparing reactive dye ink for digital inkjet printing comprises the following steps:

[0055] 1. Preparation of reactive polymer microsphere dispersion:

[0056] (1) Add a certain amount of distilled water to a reaction container, add 0.01 mol / L of methacryloyloxyethyl trimethylammonium chloride and 0.06 mol / L of glycidyl methacrylate monomer in sequence, stir for a certain period of time, and set aside;

[0057] (2) Add 0.6 g / L of styrene monomer, stir thoroughly, heat from room temperature to 70°C, add 0.002 g / L of 2,2'-azobisisobutylamidine hydrochloride solution, react at constant temperature for 2 hours, and cool to room temperature to obtain a reactive polymer microsphere dispersion;

[0058] 2. Preparation of reactive dye / polymer composite microsphere dispersion:

[0059] (3) Prepare a reactive dye solution with a concentration of 80 mmol / L for later use; wherein the reactive dye solution is a mixture of reactive dye and deionized water, and the reactive dye is any one or more of CI Reactive Red 218, CI Reactive Red 24, CI Reactive Blue 72, CI Reactive Blue 15, CI Reactive Blue 49, CI Reactive Orange 13, CI Reactive Black 5, and CI Reactive Black 8.

[0060] (4) preparing the reactive polymer microsphere dispersion prepared in step (2) into a reactive polymer microsphere dispersion having a concentration of 16 g / L;

[0061] (5) under stirring conditions, slowly dropwise add the active dye solution prepared in step (3) to the reactive polymer microsphere dispersion prepared in step (4) at a volume ratio of 1:0.5, with a dropwise acceleration rate of 0.3 L / h, and continuously stir for 1 h to obtain an active dye / polymer composite microsphere dispersion;

[0062] 3. Preparation of reactive dye / polymer composite microsphere ink:

[0063] (6) preparing a coupling component / water mixed solution with a concentration of 2 wt% for standby use; wherein the coupling component is a water-soluble solvent containing hydroxyl or amino groups that can couple with the active dye / polymer composite microspheres by hydrogen bonding or hydrophobic forces, including any one or a combination of glycerol, 1,2-propylene glycol, ethylene glycol, diethylene glycol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol 200, polyethylene glycol 400, triethanolamine, ethylenediamine, and nitrilotriacetic acid;

[0064] (7) adding the prepared reactive dye / polymer composite microsphere dispersion to the coupling component / water mixed solution;

[0065] (8) Mechanically stir at room temperature for 6-24 hours, and then let stand for 12-48 hours to obtain a reactive dye ink.

[0066] The viscosity of the reactive dye ink prepared in this embodiment is 3 mPa·s, and the surface tension is 30 mN / m.

[0067] Embodiment 2:

[0068] A method for preparing reactive dye ink for digital inkjet printing comprises the following steps:

[0069] 1. Preparation of reactive polymer microsphere dispersion:

[0070] (1) Add a certain amount of distilled water to a reaction container, add 0.02 mol / L of methacryloyloxyethyl trimethyl ammonium chloride and 0.08 mol / L of glycidyl methacrylate monomer in sequence, stir for a certain period of time, and set aside;

[0071] (2) Add 1 g / L of styrene monomer, stir thoroughly, heat from room temperature to 80°C, add 0.004 g / L of 2,2'-azobisisobutylamidine hydrochloride solution, react at constant temperature for 4 hours, and cool to room temperature to obtain a reactive polymer microsphere dispersion;

[0072] 2. Preparation of reactive dye / polymer composite microsphere dispersion:

[0073] (3) preparing a reactive dye solution with a concentration of 100 mmol / L for standby use; wherein the reactive dye solution is prepared by mixing a reactive dye and deionized water, and the reactive dye is any one or more of CI Reactive Red 218, CI Reactive Red 24, CI Reactive Blue 72, CI Reactive Blue 15, CI Reactive Blue 49, CI Reactive Orange 13, CI Reactive Black 5, and CI Reactive Black 8;

[0074] (4) preparing the reactive polymer microsphere dispersion prepared in step (2) into a reactive polymer microsphere dispersion having a concentration of 20 g / L;

[0075] (5) under stirring conditions, slowly dropwise adding the active dye solution prepared in step (3) to the reactive polymer microsphere dispersion prepared in step (4) at a volume ratio of 1:1.5, with a dropwise acceleration rate of 0.3 L / h. After continuous stirring for 1 hour, an active dye / polymer composite microsphere dispersion is obtained;

[0076] 3. Preparation of reactive dye / polymer composite microsphere ink:

[0077] (6) preparing a coupling component / water mixed solution with a concentration of 6 wt % for standby use; wherein the coupling component is a water-soluble solvent containing hydroxyl or amino groups that can couple with the active dye / polymer composite microspheres by hydrogen bonding or hydrophobic forces, including any one or a combination of glycerol, 1,2-propylene glycol, ethylene glycol, diethylene glycol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol 200, polyethylene glycol 400, triethanolamine, ethylenediamine, and nitrilotriacetic acid.

[0078] (7) adding the prepared reactive dye / polymer composite microsphere dispersion to the coupling component / water mixed solution;

[0079] (8) Mechanically stir at room temperature for 6-24 hours, and then let stand for 12-48 hours to obtain a reactive dye ink.

[0080] The viscosity of the reactive dye ink prepared in this embodiment is 6 mPa·s, and the surface tension is 40 mN / m.

[0081] Embodiment 3:

[0082] A method for preparing reactive dye ink for digital inkjet printing comprises the following steps:

[0083] 1. Preparation of reactive polymer microsphere dispersion:

[0084] (1) Add a certain amount of distilled water to a reaction container, add 0.04 mol / L of methacryloyloxyethyl trimethylammonium chloride and 0.1 mol / L of glycidyl methacrylate monomer in sequence, stir for a certain period of time, and set aside;

[0085] (2) Add 1.41 g / L of styrene monomer, stir thoroughly, heat from room temperature to 90°C, add 0.006 g / L of 2,2'-azobisisobutylamidine hydrochloride solution, react at constant temperature for 6 hours, and cool to room temperature to obtain a reactive polymer microsphere dispersion;

[0086] 2. Preparation of reactive dye / polymer composite microsphere dispersion:

[0087] (3) preparing a reactive dye solution with a concentration of 120 mmol / L for standby use; wherein the reactive dye solution is prepared by mixing a reactive dye and deionized water, and the reactive dye is any one or more of CI Reactive Red 218, CI Reactive Red 24, CI Reactive Blue 72, CI Reactive Blue 15, CI Reactive Blue 49, CI Reactive Orange 13, CI Reactive Black 5, and CI Reactive Black 8;

[0088] (4) preparing the reactive polymer microsphere dispersion prepared in step (2) into a reactive polymer microsphere dispersion having a concentration of 24 g / L;

[0089] (5) under stirring conditions, slowly dropwise adding the active dye solution prepared in step (3) to the reactive polymer microsphere dispersion prepared in step (4) at a volume ratio of 1:3, with a dropwise acceleration rate of 0.3 L / h. After continuous stirring for 1 hour, an active dye / polymer composite microsphere dispersion is obtained;

[0090] 3. Preparation of reactive dye / polymer composite microsphere ink:

[0091] (6) preparing a coupling component / water mixed solution with a concentration of 10 wt% for standby use; wherein the coupling component is a water-soluble solvent containing hydroxyl or amino groups that can couple with the active dye / polymer composite microspheres by hydrogen bonding or hydrophobic forces, including any one or a combination of glycerol, 1,2-propylene glycol, ethylene glycol, diethylene glycol, 1,3-butanediol, 1,4-butanediol, polyethylene glycol 200, polyethylene glycol 400, triethanolamine, ethylenediamine, and nitrilotriacetic acid.

[0092] (7) adding the prepared reactive dye / polymer composite microsphere dispersion to the coupling component / water mixed solution;

[0093] (8) Mechanically stir at room temperature for 6-24 hours, and then let stand for 12-48 hours to obtain a reactive dye ink.

[0094] The viscosity of the reactive dye ink prepared in this embodiment is 10 mPa·s, and the surface tension is 50 mN / m.

[0095] The performance test results of the reactive dye ink prepared by the preparation method described in Example 2 of the present invention and its specific application are as follows:

[0096] 1. About the morphology, structure, dyeing mechanism and dyeing effect of reactive dye / polymer composite microspheres.

[0097] like Figure 4As shown, in the reactive dye / polymer composite microsphere dispersion, the surface of the reactive dye / polymer microsphere is relatively smooth, the core-shell structure is obvious, and the particle size distribution is uniform. It can be seen that the reactive dye ink prepared by the present invention can form a dense polymer film on the fiber surface more uniformly through the reactive dye / polymer microsphere and adhere to the fiber surface, significantly improving the dye fixation rate and color fastness.

[0098] like Figure 5 As shown, Figure 5 (a) is the surface morphology of cotton fabric after inkjet printing with common reactive dye ink. It can be clearly seen from the figure that the fiber surface is clean and clear; Figure 5 (b) is a surface morphology of cotton fabric after inkjet printing with the reactive dye / polymer composite microsphere ink of the present invention, which clearly forms a polymer coating on the fiber surface. The surface of the fabric printed with the reactive dye ink is flat and smooth, because the reactive dye mainly diffuses into the interior of the fiber and does not affect the fiber surface morphology. The difference is that a continuous polymer coating can be observed on the sample surface after the reactive dye / polymer composite microsphere inkjet printing, and the composite microspheres on this surface are cross-linked on the fabric surface. Because the composite microspheres have unique self-crosslinking properties, multiple interactions can be established between the reactive dye and the cotton fiber, and more reactive dyes are stably fixed on the fabric surface.

[0099] like Figure 6 As shown, from the comparison of the printing pattern effects, it can be seen that the color depth of the pattern printed by the self-cross-linking active dye / polymer composite microsphere ink of the present invention is deeper, because the surface of the microspheres has reactive groups such as epoxy groups and isotriazine, which can covalently bond with cellulose fibers, and the dye fixation rate is higher.

[0100] 2. About color fixation rate, color fastness and soap fastness.

[0101] Table 1 shows a comparison of the color fixation rate and color fastness of the self-crosslinkable reactive dye / polymer microsphere ink of the present invention and common commercial reactive dye ink.

[0102] Table 1:

[0103]

[0104] As shown in Table 1, the active groups of commercial reactive dye inks are hydrolyzed during ink storage and steaming, so some reactive dyes are difficult to combine with cellulose fibers and exist on the fabric surface in the form of "floating colors". The color fixation rate is difficult to reach 90%, and the rubbing fastness and soap fastness are poor. For the reactive dye / polymer microsphere ink of the present invention, the reactive dye is combined with the microspheres by electrostatic force, and because there are reactive groups such as epoxy groups and triazine on the surface of the microspheres, they can be covalently combined with cellulose fibers. Therefore, the microspheres establish multiple interactions between the reactive dyes and the fibers, and the color fixation rate is significantly increased to more than 98.5%. The measured rubbing fastness and soap fastness are high, and there is almost no fading during the test.

[0105] It can be seen that the self-crosslinkable reactive dye / polymer microsphere ink of the present invention has higher color fastness than traditional commercial reactive dye ink, and hardly fades during washing and friction. Therefore, no washing is required after inkjet printing, and no colored wastewater is discharged, which has significant environmental advantages.

[0106] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Any changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention should fall within the protection scope of the present invention.

Claims

1. A method for preparing reactive dye ink for digital inkjet printing, characterized in that: The steps include:

1. Preparation of reactive polymer microsphere dispersion: (1) Add a certain amount of distilled water to a reaction container, add 0.01-0.04 mol / L of methacryloyloxyethyl trimethyl ammonium chloride and 0.06-0.1 mol / L of glycidyl methacrylate monomer in sequence, stir for a certain period of time, and set aside; (2) adding 0.6-1.41 g / L of styrene monomer, stirring thoroughly, heating from room temperature to 70-90° C., adding 0.002-0.006 g / L of 2,2'-azobisisobutylamidine hydrochloride solution, reacting at constant temperature for 2-6 hours, and cooling to room temperature to obtain a reactive polymer microsphere dispersion; 2. Preparation of reactive dye / polymer composite microsphere dispersion: (3) Prepare a reactive dye solution with a concentration of 80-120 mmol / L for standby use; (4) preparing the reactive polymer microsphere dispersion prepared in step (2) into a reactive polymer microsphere dispersion having a concentration of 16-24 g / L; (5) under stirring conditions, slowly adding the active dye solution prepared in step (3) to the reactive polymer microsphere dispersion prepared in step (4) at a certain volume ratio, and continuously stirring for 1 hour to obtain an active dye / polymer composite microsphere dispersion; 3. Preparation of reactive dye / polymer composite microsphere ink: (6) Prepare a coupling component / water mixed solution with a concentration of 2-10 wt% for standby use; (7) adding the prepared reactive dye / polymer composite microsphere dispersion to the coupling component / water mixed solution; (8) Mechanically stir the mixture at room temperature for 6-24 hours, and then allow to stand for 12-48 hours to obtain a reactive dye ink.

2. The method for preparing reactive dye ink for digital inkjet printing according to claim 1, characterized in that: In the step (1), the concentration of methacryloyloxyethyltrimethylammonium chloride is 0.02 mol / L, and the concentration of glycidyl methacrylate monomer is 0.08 mol / L.

3. The method for preparing reactive dye ink for digital inkjet printing according to claim 1, characterized in that: In the step (2), the mass fraction of styrene monomer is 1 g / L. After sufficient stirring, the temperature is raised from room temperature to 80° C., 0.004 g / L of 2,2'-azobisisobutylamidine hydrochloride solution is added, and the reaction is carried out at a constant temperature for 4 hours.

4. The method for preparing reactive dye ink for digital inkjet printing according to claim 1, characterized in that: In the step (3), the reactive dye solution is prepared by mixing reactive dye and deionized water, and the concentration is 100 mmol / L, wherein the reactive dye is any one or more of CI Reactive Red 218, CI Reactive Red 24, CI Reactive Blue 72, CI Reactive Blue 15, CI Reactive Blue 49, CI Reactive Orange 13, CI Reactive Black 5, and CI Reactive Black 8.

5. The method for preparing reactive dye ink for digital inkjet printing according to claim 1, characterized in that: In the step (4), the concentration of the reactive polymer microsphere dispersion is 20 g / L.

6. The method for preparing reactive dye ink for digital inkjet printing according to claim 1, characterized in that: In the step (5), the volume ratio of the active dye solution to the reactive polymer microsphere dispersion is 1:0.5-1:3, and the dripping rate is 0.3 L / h.

7. The method for preparing reactive dye ink for digital inkjet printing according to claim 1, characterized in that: In the step (6), the concentration of the coupling component / water mixed solution is 6 wt %.

8. The method for preparing reactive dye ink for digital inkjet printing according to claim 1, characterized in that: In the step (6), the coupling component is a water-soluble solvent containing hydroxyl or amino groups that can couple with the active dye / polymer composite microspheres by hydrogen bonds or hydrophobic forces, including one or a combination of glycerol, 1,2-propylene glycol, ethylene glycol, diethylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, polyethylene glycol 200, polyethylene glycol 400, triethanolamine, ethylenediamine, and nitrilotriacetic acid.

9. A reactive dye ink for digital inkjet printing, characterized in that: Prepared by the preparation method according to any one of claims 1 to 8.

10. The reactive dye ink for digital inkjet printing according to claim 9, characterized in that: The viscosity of the reactive dye ink is 3-10 mPa·s, and the surface tension is 30-50 mN / m.

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