Preparation method and dyeing method of liquid disperse dye

Abstract

The invention relates to the field of dyeing and finishing, and discloses a preparation method and a dyeing method of a liquid disperse dye. The preparation method comprises the following steps: 1) mixing a disperse dye filter cake with nekal BX, and carrying out a colloid mill; (2) uniformly mixing dye particles, a dispersing agent TL-104PG, a dispersing agent Dispersogen AN 100 and water, and sanding, so as to obtain a roughly ground liquid disperse dye; and 3) uniformly mixing the polyacrylamide polymer aqueous solution with the coarsely ground liquid disperse dye, and sanding to obtain the liquid disperse dye. The liquid disperse dye prepared by the invention also has the characteristics of uniform particle size distribution, good dispersibility and good room temperature / high temperature dispersion stability under the conditions of low dispersant addition amount and high dye solid content. When being used for dyeing polyester fabrics, the liquid disperse dye has excellent dyeing improving property and leveling property; meanwhile, indexes such as COD (Chemical Oxygen Demand) of dyeing raffinate and washing raffinate of the liquid disperse dye are superior to those of powder disperse dye.

Description

Technical Field

[0001] The present invention relates to the field of dyeing and finishing, and particularly to a preparation method and a dyeing method of a liquid disperse dye. Background Art

[0002] Disperse dyes are the main dyes used for dyeing polyester fibers. Their structures do not contain ionizable water-soluble groups and have very low solubility in water. Therefore, for the requirements of facilitating the storage, transportation of disperse dyes and the rapid dispersion of dyes during dyeing, commercial disperse dyes are mostly in powder form. During the commercialization process, a large amount of dispersant needs to be added (the dosage of the dispersant is usually 1-2 times the weight of the disperse dye filter cake). Since a large amount of dispersant will solubilize the disperse dye in the dye bath, it will prevent the dye from dyeing the fabric. Moreover, after the dyeing is completed, a large amount of disperse dyes solubilized by micelles in the dye bath enter the dyeing wastewater, increasing the burden of wastewater treatment. In addition, the dye solubilized due to the presence of a large number of surfactant micelles on the fabric surface not only prevents the dye from dyeing, but also leaves more undyed dyes on the fabric surface, resulting in floating color, which affects the color fastness of the dyed fabric. Therefore, in order to obtain a certain color fastness, the dyed fabric with powder disperse dyes must go through a series of high-temperature water washing processes such as reduction cleaning to remove the surface floating color. A large amount of reduction cleaning aids are discharged into the wastewater, causing water pollution. Due to the presence of a large amount of dispersant, the powder disperse dye has high energy consumption and large pollution in the entire dyeing process.

[0003] Compared with powder disperse dyes, the dosage of the dispersant in liquid disperse dyes can be greatly reduced. On the one hand, it can reduce the solubilization of the dye by the dispersant micelles in the dye bath and reduce the burden of dyeing wastewater treatment. On the other hand, it can reduce the solubilization of the dye by the surfactant micelles of the dispersant on the fabric, reduce the floating color on the surface of the dyed fabric, and is expected to reduce the washing intensity of the dyed fabric and shorten the water washing process. However, compared with powder disperse dyes, the liquid disperse dye has poor dispersion stability during storage and transportation. In order to improve the dispersion stability of the liquid disperse dye during storage and transportation, currently two methods are generally adopted: one method is to increase the dosage of the dispersant, but this is not conducive to the low-emission dyeing of the liquid disperse dye; the other method is to reduce the limited content (i.e., low solid content) of the liquid disperse dye filter cake during preparation, but this is not conducive to the lifting power of the liquid disperse dye during dyeing application and increases the transportation and storage costs. Therefore, the stable preparation of low-emission and high-lifting liquid disperse dyes has become a bottleneck problem restricting the industrial application of liquid disperse dyes.

[0004] The key to solving the above problems is to design and adopt a dispersant with a suitable structure to achieve efficient grinding of high-solid-content disperse dyes (filter cakes), and to use suitable additives to improve the stability of the liquid disperse dyes after grinding. At present, liquid disperse dyes are mostly prepared by using single or compound-component dispersants such as naphthalene sulfonic acid formaldehyde condensate and lignosulfonates. Although nano-level liquid disperse dyes can be prepared through them, there are still problems of low grinding efficiency and poor stability when the dosage of the dispersant is small and the solid content of the liquid disperse dyes is high. At present, there is little research on stable disperse dyes with high liftability (high dye solid content) at low dispersant dosage (requirements for low-emission dyeing processes), and there is an urgent need to further develop new products. Summary of the Invention

[0005] In view of the problems existing in the above liquid disperse dyes, the present invention provides a preparation method and a dyeing method for liquid disperse dyes. Combining the molecular structure of disperse dyes and the properties of the liquid disperse dye dispersion system, the present invention designs a preparation method of ① pretreating the high-solid-content disperse dye filter cake with Nekal BX → ② performing sand grinding and dispersion with a high-efficiency dispersant → ③ adding an anionic polyacrylamide polymer during the stabilization process to regulate the viscosity of the disperse dye. The liquid disperse dyes prepared by the method of the present invention have the characteristics of uniform particle size distribution, good dispersibility and dispersion stability (room temperature / high temperature) even at low dispersant addition amounts and high dye solid contents, and can greatly reduce the wastewater discharge amount and COD discharge amount during the high-temperature dipping of polyester fabrics.

[0006] The specific technical solution of the present invention is as follows: In a first aspect, the present invention provides a preparation method for liquid disperse dyes, comprising the following steps: 1) Pretreatment: Mix the wetted disperse dye filter cake with Nekal BX, and treat it with a colloid mill until the particle size of the dye ≤ 100 μm.

[0007] 2) Sand grinding and dispersion: Mix the dye particles obtained by grinding in step 1), dispersant TL-104PG, dispersant Dispersogen AN 100 and water, stir evenly, and perform sand grinding treatment to obtain a roughly ground liquid disperse dye.

[0008] 3) Dispersion stabilization: Add an aqueous solution of anionic polyacrylamide polymer to the roughly ground liquid disperse dye, mix evenly, and perform sand grinding treatment to obtain a liquid disperse dye with a dye solid content of 30-35 wt%.

[0009] As described in the background art section, liquid disperse dyes in the prior art generally have the disadvantages of low dye grinding efficiency and poor dispersion stability under the conditions of low dispersant dosage and high dye solid content. For this reason, in combination with the molecular structure of disperse dyes and the properties of the liquid disperse dye dispersion system, the present invention designs a preparation method for achieving a high stability effect of liquid disperse dyes, which includes pretreating the high-solid-content disperse dye filter cake with Nekal BX → then performing sand grinding and dispersion using a high-efficiency dispersant → and finally adding an anionic polyacrylamide polymer during the stabilization process to regulate the viscosity of the disperse dye. The liquid disperse dye prepared by this process has a uniform particle size distribution, good dispersibility and room temperature / high temperature dispersion stability even under low dispersant addition amounts and high dye solid contents, and can significantly reduce the wastewater discharge and COD discharge during the high-temperature dyeing of polyester fabrics.

[0010] In step 1), after selecting Nekal BX for pretreatment with the wet disperse dye filter cake, it can be quickly adsorbed onto the surface of solid dye particles, effectively excluding a large amount of voids (air) on the surface of solid dye particles, which is beneficial to the wetting and penetration of the disperse dye during subsequent sand grinding.

[0011] In step 2), the reason for selecting the dispersant TL-104PG is that it can not only rapidly reduce the dynamic surface tension of the dye during sand grinding, but more importantly, the present invention discovers that it also has a persistent defoaming property compared with other types of surfactants, which can effectively avoid the side effects of bubbles on grinding during sand grinding (the presence of bubbles is not conducive to the wetting and penetration of solid dye particles). The reason for selecting the dispersant Dispersogen AN 100 is that it belongs to an anionic / nonionic compound type dispersant and has a multi-benzene ring structure in its molecular structure, which can form a strong Π-Π interaction with the dye, form multi-point adsorption and firm anchoring on the surface of the dye particles. At the same time, the combined action of the steric hindrance of the long ethylene oxide chain and the electrostatic repulsion of the anionic group can stabilize the disperse dye particles and improve the high-temperature dispersion stability of the liquid disperse dye.

[0012] In step 3), the reason for selecting the anionic polyacrylamide polymer as a stabilizer is that, compared with other types of stabilizers, the molecular structure of the anionic polyacrylamide polymer contains water-soluble carboxyl groups and polar amide groups, which can form hydrogen bonds with water to form bound water, and can also hold water through physical entanglement of the molecular chains. Therefore, it can better increase the viscosity of the liquid disperse dye system and reduce the sedimentation of disperse dye particles caused by movement and collision.

[0013] It should be further emphasized that the key reason why the present invention can achieve the characteristics of uniform particle size distribution, good dispersibility and dispersion stability of liquid disperse dyes even at low dispersant addition amounts and high dye solid contents lies in the selection of reagent types such as Nekal BX, dispersants, and stabilizers. The present invention discovers that when using the specific combination of "Nekal BX + dispersant TL-104PG + dispersant Dispersogen AN 100 + anionic polyacrylamide polymer", better technical effects can be achieved compared to other reagent combinations, that is, the above specific reagent combination of the present invention can achieve better synergistic effects.

[0014] Preferably, in step 1), the dosage of Nekal BX is 1-3% of the dry weight of the disperse dye filter cake.

[0015] The present invention discovers that the dosage of Nekal BX in step 1) is extremely crucial for the treatment effect of subsequent steps. If the dosage is too small, a large number of voids (air) on the surface of solid dye particles cannot be completely eliminated; conversely, if the dosage is too large, the effects of other additives will be affected. Finally, the present invention discovers that controlling the dosage of Nekal BX within the range of 1-2% of the dry weight of the disperse dye filter cake has the best effect.

[0016] Preferably, in step 1), the solid content of the wetted disperse dye filter cake is 35-50 wt%.

[0017] Preferably, in step 1), the motor speed of the colloid mill treatment is 2800-3000 r / min.

[0018] Preferably, in step 2), the dosage of dispersant TL-104PG is 2-4% of the dry weight of the disperse dye filter cake in step 1); the dosage of dispersant Dispersogen AN 100 is 10-15% of the dry weight of the disperse dye filter cake in step 1).

[0019] The present invention discovers that the dosages of the two dispersants in step 2) are both relatively important for the particle size and dispersion stability of the final liquid disperse dye. Finally, the present invention discovers that controlling the dosages of the two dispersants within the above ranges has the best effect.

[0020] Preferably, in step 2), the dosage of water is 33-67% of the dry weight of the disperse dye filter cake in step 1).

[0021] Preferably, in step 2), the bead milling treatment uses grinding beads with a diameter of 0.8-1.2 mm; the bead milling treatment time is 3-5 h.

[0022] Preferably, in step 3), the molecular weight of the anionic polyacrylamide polymer is 16 million - 18 million; the dosage of the anionic polyacrylamide polymer is controlled to make the viscosity of the system be 500 - 800 mPa·s.

[0023] Preferably, in step 3), the bead milling treatment uses grinding beads with a diameter of 0.4 - 0.6 mm; the bead milling treatment time is 1 - 2 h.

[0024] In a second aspect, the present invention provides a method for dyeing a liquid disperse dye, comprising: formulating the liquid disperse dye of the present invention into a dye solution, immersing the fabric in the dye solution for dyeing, and washing with water at room temperature after dyeing is completed to obtain a dyed fabric.

[0025] Preferably, the fabric is a polyester fabric.

[0026] Preferably, the dosage of the liquid disperse dye is 0.1 - 3% (o.w.f.).

[0027] Preferably, the dyeing temperature is 120 - 140 °C, the dyeing heat preservation time is 20 - 40 min; the dyeing bath ratio is 1:(10 - 20); the pH value of the dye bath is 4 - 6.

[0028] Preferably, the time for washing with water at room temperature is 5 - 15 min.

[0029] Compared with the prior art, the present invention has the following technical effects: (1) The present invention combines the molecular structure of the disperse dye and the properties of the liquid disperse dye dispersion system, and designs a preparation method of ① pretreating the high-solid-content disperse dye filter cake with Nekal BX → ② performing bead milling dispersion with a high-efficiency dispersant → ③ adding an anionic polyacrylamide polymer during the stabilization process to regulate the viscosity of the disperse dye. The liquid disperse dye prepared by the present invention has the characteristics of uniform particle size distribution, good dispersion and room temperature / high temperature dispersion stability even at low dispersant addition amounts and high dye solid contents, and can greatly reduce the wastewater discharge amount and COD discharge amount during the high-temperature dipping of polyester fabrics.

[0030] (2) By optimizing the selection of the reagent types of Nekal BX, the dispersant and the stabilizer, the present invention finds that the specific combination of "Nekal BX + dispersant TL-104PG + dispersant Dispersogen AN 100 + anionic polyacrylamide polymer" can achieve better synergistic effects and has better technical effects than other types of reagent combinations.

[0031] (3) By optimizing the dosages of Nekal BX, the dispersant and the stabilizer in each step, the present invention can obtain a liquid disperse dye with a more uniform particle size distribution, better dispersion and dispersion stability. (4) Dyeing polyester fibers with the liquid disperse dyes prepared by the method of the present invention, various indexes such as dyeing build-up property and levelness reach the level of powder disperse dyes, and the dyeing build-up property is significantly improved compared with the currently commercially available liquid disperse dyes; meanwhile, under the condition that the rubbing fastness of the dyed fabric is 4 grades, indexes such as COD of the dyeing residual liquid and washing residual liquid of the liquid disperse dyes are better than those of the powder disperse dyes. Description of the Drawings

[0032] Figure 1 It is a graph of the average particle size change of the liquid disperse dyes prepared in Examples 1-3 at room temperature; Figure 2 It is a graph of the average particle size change of the liquid disperse dyes prepared in Examples 1-3 at 60±2 °C. Detailed Embodiments

[0033] The present invention will be further described below in conjunction with the embodiments.

[0034] A preparation method of a liquid disperse dye, comprising the following steps: 1) Pretreatment: Mix the wetted disperse dye filter cake (solid content 35-50 wt%) with Nekal BX, and process with a colloid mill (motor speed 2800-3000 r / min) until the particle size of the dye ≤ 100 μm. Among them, the dosage of Nekal BX is 1-3% of the dry weight of the disperse dye filter cake.

[0035] 2) Sand grinding and dispersion: Mix the dye particles obtained by grinding in step 1), dispersant TL-104PG, dispersant Dispersogen AN 100 and water, stir evenly, and perform sand grinding treatment (using grinding beads with a diameter of 0.8-1.2 mm, 3-5 h) to obtain a roughly ground liquid disperse dye. Among them, the dosage of dispersant TL-104PG is 2-4% of the dry weight of the disperse dye filter cake; the dosage of dispersant Dispersogen AN 100 is 10-15% of the dry weight of the disperse dye filter cake; the dosage of water is 33-67% of the dry weight of the disperse dye filter cake.

[0036] 3) Dispersion and stabilization: Add an aqueous solution of anionic polyacrylamide polymer (molecular weight 16 million - 18 million) to the roughly ground liquid disperse dye, mix evenly, and perform sand grinding treatment (using grinding beads with a diameter of 0.4-0.6 mm, 1-2 h) to obtain a liquid disperse dye with a dye solid content of 30-35 wt% and a system viscosity of 500-800 mPa·s.

[0037] A dyeing method using liquid disperse dyes: preparing a dyeing solution with liquid disperse dyes, immersing fabric (preferably polyester fabric) in the dyeing solution for dyeing, wherein the amount of liquid disperse dyes used is 0.1-3% (owf), the dyeing temperature is 120-140°C, the dyeing heat preservation time is 20-40min, the dyeing bath ratio is 1:(10-20), and the pH value of the dyeing bath is 4-6. After dyeing, the fabric is washed with water at room temperature for 5-15min to obtain a dyed fabric.

[0038] Example 1 (Preparation of Liquid Disperse Red 167) (1) 6 g of BX powder and 705.9 g of wet Disperse Red 167 filter cake (42.5% of the dye filter cake weight) were mixed and ground on a colloid mill at a motor speed of 2900 r / min until the particle size was less than 100 μm (using a 200 mesh standard sieve to ensure that no residue was left).

[0039] (2) Select 9 g of dispersant TL-104PG (a product of Wuhan Aoke Specialty Chemical Co., Ltd.), 30 g of dispersant Dispersogen AN100 (a product of Klein Company), the particles ground in step (1), and 200 g of water, mix them thoroughly, stir them evenly with a mechanical stirrer, transfer them to a sand mill equipped with zirconium oxide beads (bead diameter 1 mm), and grind them for 4 hours to obtain liquid disperse dye①.

[0040] (3) 50 g of water-soluble anionic polyacrylamide polymer (molecular weight 16 million to 18 million) was pre-prepared into an aqueous solution, and added to the liquid disperse dye ① obtained in step (2). After mixing evenly, the mixture was transferred to a sand mill equipped with zirconium oxide beads (bead diameter 0.5 mm) and ground for 1.5 hours to obtain the target liquid disperse dye ②. The viscosity of the liquid disperse dye ② after discharge was measured to be 624 mPa·s.

[0041] (4) The polyester fabric was dyed with a disperse dye dosage of 1% (owf), a dye bath pH of about 5, a dyeing temperature of 130°C, a dyeing holding time of 30 min, a dye bath ratio of 1:15, and washed at room temperature for 10 min.

[0042] Example 2 (Preparation of Liquid Dispersed Orange 40) (1) Mix 9 g of Lakai powder BX and 753.8 g of wet Disperse Orange 40 filter cake (39.8% of the dye filter cake weight) and grind and disperse them on a colloid mill at a motor speed of 2900 r / min until the particle size is less than 100 μm (using a 200 mesh standard sieve to ensure that no residue is left).

[0043] (2) Select 6 g of dispersant TL-104PG (product of Wuhan Aoke Special Chemical Co., Ltd.), 45 g of dispersant Dispersogen AN 100 (product of Clariant), the ground particles from step (1), and 149 g of water. After fully mixing, stir evenly with a mechanical stirrer, and transfer to a sand mill containing zirconia beads (bead diameter 1 mm) for grinding for 4 hours to obtain liquid disperse dye ①.

[0044] (3) Dissolve 37 g of anionic polyacrylamide polymer (molecular weight 16 million - 18 million) in water in advance to prepare an aqueous solution, add it to the liquid disperse dye ① obtained in step (2), mix evenly, and then transfer to a sand mill containing zirconia beads (bead diameter 0.5 mm) for grinding for 2 hours to obtain the target liquid disperse dye ②. The measured viscosity of the liquid disperse dye ② after discharging is 684 mPa·s.

[0045] (4) Dye polyester fabric. The dosage of disperse dye is 1% (o.w.f.), the pH value of the dye bath is about 5, the dyeing temperature is 130 °C, the dyeing holding time is 30 min, the dyeing bath ratio is 1∶15, and wash with room temperature water for 10 min.

[0046] Example 3 (Preparation of Liquid Disperse Blue 79) (1) Mix 7 g of Nekal BX and 774.3 g of wet filter cake of disperse blue 79 (dry weight of the dye filter cake is 45.2%), and perform grinding and dispersion on a colloid mill. The motor speed is 2900 r / min, and grind and disperse until the particle size is below 100 μm (use a 200-mesh standard sieve to detect and ensure no residue remains).

[0047] (2) Select 10.5 g of dispersant TL-104PG (product of Wuhan Aoke Special Chemical Co., Ltd.), 50 g of dispersant Dispersogen AN 100 (product of Clariant), the ground particles from step (1), and 127 g of water. After fully mixing, stir evenly with a mechanical stirrer, and transfer to a sand mill containing zirconia beads (bead diameter 1 mm) for grinding for 3 hours to obtain liquid disperse dye ①.

[0048] (3) Dissolve 32 g of anionic polyacrylamide polymer (molecular weight 16 million - 18 million) in water in advance to prepare an aqueous solution, add it to the liquid disperse dye ① obtained in step (2), mix evenly, and then transfer to a sand mill containing zirconia beads (bead diameter 0.5 mm) for grinding for 1 hour to obtain the target liquid disperse dye ②. The measured viscosity of the liquid disperse dye ② after discharging is 693 mPa·s.

[0049] (4) The polyester fabric is dyed. The dosage of the disperse dye is 1% (o.w.f.), the pH value of the dye bath is about 5, the dyeing temperature is 130 °C, the dyeing heat preservation time is 30 min, the dyeing bath ratio is 1:15, and it is washed with room temperature water for 10 min.

[0050] Example 4 (Preparation of Liquid Disperse Red 167) (1) After mixing 6 g of Nekal BX and 705.9 g of wet cake of disperse red 167 (dry weight of the dye filter cake is 42.5%), it is ground and dispersed on a colloid mill machine. The motor speed is 3000 r / min, and it is ground and dispersed until the particle size is below 100 μm (detected with a 200-mesh standard sieve to ensure no residue remains).

[0051] (2) 9 g of dispersant TL-104PG (product of Wuhan Aoke Special Chemical Co., Ltd.), 30 g of dispersant Dispersogen AN100 (product of Clariant), the particles ground in step (1), and 200 g of water are fully mixed and then stirred evenly with a mechanical stirrer, and transferred to a sand mill equipped with zirconia beads (bead diameter 1 mm) and ground for 5 hours to obtain liquid disperse dye ①.

[0052] (3) 50 g of water is used to dissolve an anionic polyacrylamide polymer (molecular weight 16 million - 18 million) and pre-configured into an aqueous solution, which is added to the liquid disperse dye ① obtained in step (2). After mixing evenly, it is transferred to a sand mill equipped with zirconia beads (bead diameter 0.5 mm) and ground for 2 hours to obtain the target liquid disperse dye ②. The measured viscosity of the liquid disperse dye ② after discharging is 603 mPa·s.

[0053] (4) The polyester fabric is dyed. The dosage of the disperse dye is 1.5% (o.w.f.), the pH value of the dye bath is about 4.5, the dyeing temperature is 120 °C, the dyeing heat preservation time is 40 min, the dyeing bath ratio is 1:20, and it is washed with room temperature water for 15 min.

[0054] Example 5 (Preparation of Liquid Disperse Orange 40) (1) After mixing 9 g of Nekal BX and 753.8 g of wet cake of disperse orange 40 (dry weight of the dye filter cake is 39.8%), it is ground and dispersed on a colloid mill machine. The motor speed is 2800 r / min, and it is ground and dispersed until the particle size is below 100 μm (detected with a 200-mesh standard sieve to ensure no residue remains).

[0055] (2) Select 6 g of dispersant TL-104PG (a product of Wuhan Aoke Specialty Chemical Co., Ltd.), 45 g of dispersant Dispersogen AN 100 (a product of Klein Company), the particles ground in step (1), and 149 g of water, mix them thoroughly, stir them evenly with a mechanical stirrer, transfer them to a sand mill equipped with zirconium oxide beads (bead diameter 1 mm), and grind them for 3 hours to obtain liquid disperse dye①.

[0056] (3) 37 g of water-soluble anionic polyacrylamide polymer (molecular weight 16 million to 18 million) was pre-prepared into an aqueous solution, and added to the liquid disperse dye ① obtained in step (2). After mixing evenly, the mixture was transferred to a sand mill equipped with zirconium oxide beads (bead diameter 0.5 mm) and ground for 1 hour to obtain the target liquid disperse dye ②. The viscosity of the liquid disperse dye ② after discharge was measured to be 664 mPa·s.

[0057] (4) The polyester fabric was dyed with a disperse dye dosage of 0.5% (owf), a dye bath pH of about 6, a dyeing temperature of 140°C, a dyeing holding time of 20 min, a dye bath ratio of 1:10, and washed at room temperature for 5 min.

[0058] Example 6 (Preparation of Liquid Dispersion Blue 79) (1) Mix 7 g of BX powder and 774.3 g of wet Disperse Blue 79 filter cake (45.2% of the dye filter cake weight) and grind and disperse them on a colloid mill at a motor speed of 3000 r / min until the particle size is less than 100 μm (using a 200 mesh standard sieve to ensure that no residue is left).

[0059] (2) Select 10.5 g of dispersant TL-104PG (a product of Wuhan Aoke Specialty Chemical Co., Ltd.), 50 g of dispersant Dispersogen AN 100 (a product of Klein Company), the particles ground in step (1), and 127 g of water, mix them thoroughly, stir them evenly with a mechanical stirrer, transfer them to a sand mill equipped with zirconium oxide beads (bead diameter 1 mm), and grind them for 5 hours to obtain liquid disperse dye①.

[0060] (3) 32 g of water-soluble anionic polyacrylamide polymer (molecular weight 16 million to 18 million) was pre-prepared into an aqueous solution, and added to the liquid disperse dye ① obtained in step (2). After mixing evenly, the mixture was transferred to a sand mill equipped with zirconium oxide beads (bead diameter 0.5 mm) and ground for 2 hours to obtain the target liquid disperse dye ②. The viscosity of the liquid disperse dye ② after discharge was measured to be 712 mPa·s.

[0061] (4) The polyester fabric was dyed with a 3% (o.w.f.) dosage of disperse dyes, the pH value of the dye bath was about 4, the dyeing temperature was 135 °C, the dyeing holding time was 25 min, the dyeing bath ratio was 1:18, and it was washed with room temperature water for 15 min.

[0062] Performance Testing (I) Storage Stability: The storage stability of the liquid disperse dyes of Examples 1 - 3 (based on the average particle size D50 of the dyes tested by a laser particle size analyzer (Dandong Baite Instrument Co., Ltd.)) is as Figure 1 and Figure 2 shown. The change in the average particle size of the dyes with time during storage at room temperature and in an incubator at (60 ± 2) °C was tested.

[0063] It can be seen from Figure 1 and Figure 2 that the liquid disperse dyes prepared in Examples 1 - 3 all have excellent storage stability.

[0064] (II) Dyeing Performance: The polyester fabric was dyed with the liquid disperse dyes of Examples 1, 2, and 3 respectively and the powder disperse dyes of our company (powdered disperse red 167, powdered disperse orange 30, powdered disperse blue 79 (brand numbers are HXF - 167, HXF - 30, HXF - 79)) using the same dyeing process. The dyeing build - up property and dyeing unevenness are compared as shown in Tables 1 - 3.

[0065] Table 1: Dyeing Performance of Disperse Red 167 Table 2: Dyeing Performance of Disperse Orange 30 Table 3: Dyeing Performance of Disperse Blue 79 It can be seen from Tables 1 - 3 that the dyeing build - up property and dyeing uniformity of the liquid disperse dyes of Examples 1 - 3 basically reach the level of the powder disperse dyes.

[0066] (III) COD Values of Dyeing Residual Liquor and Washing Residual Liquor: Under the condition that the rubbing fastness of the dyed fabric is 4 - grade, the COD of the dyeing residual liquor and washing residual liquor after dyeing with disperse dyes at different dyeing concentrations was compared, and the results are shown in Tables 4 and 5.

[0067] Table 4: COD Values of 3% Disperse Dye Dyeing Residual Liquor and Washing Residual Liquor Table 5: COD Values of 5% Disperse Dye Dyeing Residual Liquor and Washing Residual Liquor As can be seen from Table 4 and Table 5, at the same dyeing concentration, when the dyed fabric reaches color fastness level 4, the COD of the dyeing residual liquid and washing residual liquid of the liquid disperse dye is much lower than that of the powder disperse dye, and the higher the dyeing concentration, the greater the reduction value of COD.

[0068] Unless otherwise specified, the raw materials and equipment used in the present invention are all common raw materials and equipment in the art; unless otherwise specified, the methods used in the present invention are all conventional methods in the art.

[0069] The above are only the preferred embodiments of the present invention, and do not impose any limitations on the present invention. Any simple modifications, changes, and equivalent transformations made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A preparation method of a liquid disperse dye, characterized in that It includes the following steps: 1) Pretreatment: Mix the wet disperse dye filter cake with Nekal BX, and process with a colloid mill until the particle size of the dye ≤ 100 μm; 2) Sand grinding and dispersion: Mix the dye particles obtained by grinding in step 1), dispersant TL-104PG, dispersant Dispersogen AN100 and water, stir evenly, and perform sand grinding treatment to obtain a coarsely ground liquid disperse dye; 3) Dispersion stabilization: Add an aqueous solution of anionic polyacrylamide polymer to the coarsely ground liquid disperse dye, mix evenly, and perform sand grinding treatment to obtain a liquid disperse dye with a dye solid content of 30-35 wt%.

2. The preparation method according to claim 1, characterized in that: In step 1), the dosage of Nekal BX is 1-3% of the dry weight of the disperse dye filter cake; the solid content of the wet disperse dye filter cake is 35-50 wt%.

3. The preparation method according to claim 1 or 2, characterized in that: In step 1), the motor speed of the colloid mill treatment is 2800-3000 r / min.

4. The preparation method according to claim 1, characterized in that: In step 2), the dosage of dispersant TL-104PG is 2-4% of the dry weight of the disperse dye filter cake in step 1); the dosage of dispersant Dispersogen AN 100 is 10-15% of the dry weight of the disperse dye filter cake in step 1); the dosage of water is 33-67% of the dry weight of the disperse dye filter cake in step 1).

5. The preparation method according to claim 1 or 4, characterized in that: In step 2), the sand grinding treatment uses grinding beads with a diameter of 0.8-1.2 mm; the sand grinding treatment time is 3-5 h.

6. The preparation method according to claim 1, characterized in that: In step 3), the molecular weight of the anionic polyacrylamide polymer is 16 million - 18 million; the dosage of the anionic polyacrylamide polymer is based on controlling the system viscosity at 500-800 mPa·s.

7. The preparation method according to claim 5, characterized in that: In step 3), the sand grinding treatment uses grinding beads with a diameter of 0.4-0.6 mm; the sand grinding treatment time is 1-2 h.

8. A dyeing method for liquid disperse dyes, characterized in that It includes: Prepare the liquid disperse dye obtained by the preparation method according to any one of claims 1-7 into a dye solution, immerse the fabric in the dye solution for dyeing, and wash it with room temperature water after dyeing to obtain a dyed fabric.

9. The preparation method according to claim 8, characterized in that: The fabric is a polyester fabric.

10. According to the preparation method of claim 8, characterized in that: the dosage of the liquid disperse dye is 0.1-3% (o.w.f.); the dyeing temperature is 120-140 °C, and the dyeing heat preservation time is 20-40 min; the dyeing bath ratio is 1:(10-20); the pH value of the dye bath is 4-6; the time of the room temperature water washing is 5-15 min.

Images