One bath dyeing process for polyester cotton blended fabric

Abstract

The application discloses a one-bath dyeing process for polyester-cotton blended fabric, which adopts polysiloxane quaternary ammonium salt as an emulsifier to prepare a supercritical CO2 microemulsion dyeing system, and controls the density of the supercritical CO2 fluid by adjusting the temperature and / or pressure in the reaction process, so that the microemulsion forms or collapses; when the stable microemulsion is formed, the microemulsion loads and delivers the reactive dye to cotton fibers to realize dyeing; when the microemulsion collapses, the solubility of the polysiloxane quaternary ammonium salt decreases, the polysiloxane quaternary ammonium salt aggregates and tends to be adsorbed on the surface of the fabric, so that the softening and antibacterial finishing effects are achieved.

Description

Technical Field

[0001] This invention relates to the field of dyeing and printing technology, and more specifically, to a one-bath dyeing process for polyester-cotton blended fabrics. Background Technology

[0002] Compared to polyester fiber fabrics, polyester-cotton blended fabrics combine the good shape retention and colorfastness of polyester fibers with the moisture absorption and breathability of cellulose fibers, making them popular with consumers and widely used in the garment manufacturing industry. Industrial production often uses one-bath or two-bath dyeing methods for polyester-cotton blended fabrics, which involve long wet processing times, low production efficiency, high consumption of water, electricity, and steam, and the discharged wastewater contains large amounts of alkali and inorganic salts, resulting in high treatment costs.

[0003] To reduce water consumption and wastewater in dyeing processes, extensive research has been conducted to develop water-saving and waterless dyeing technologies. Supercritical CO2 fluid technology utilizes reusable CO2 as the dyeing medium under supercritical conditions. Its overall cost, including energy consumption, is lower than conventional dyeing processes, achieving waterless dyeing, energy conservation, and emission reduction. Therefore, supercritical CO2 fluid dyeing technology possesses the technological advantages of being waterless, reducing emissions, and saving energy, making it a promising new technology for industrial production.

[0004] Applying supercritical CO2 (scCO2) dyeing technology to polyester-cotton blended fabrics requires overcoming the poor compatibility between scCO2 and reactive dyes, resulting in low dye uptake on cotton fibers. Constructing an emulsion system to improve the solubility of reactive dyes is one feasible approach. However, due to the low solubilization capacity of scCO2, the requirements for surfactants are quite stringent. Currently, fluorinated surfactants are mainly used. Fluorine atoms are large and highly electronegative, resulting in high CF bond energy and low polarizability, leading to weak intermolecular interactions (low cohesive energy density) between fluorine and carbon chains, and excellent compatibility with the similarly weakly interacting scCO2. However, fluorinated surfactants have drawbacks such as high price, high cost, and high toxicity.

[0005] Therefore, this invention is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a one-bath dyeing process for polyester-cotton blended fabrics, specifically a method for supercritical CO2 dyeing of polyester-cotton blended fabrics using both reactive and disperse dyes in the same bath.

[0007] This invention is implemented as follows:

[0008] In a first aspect, the present invention provides a one-bath dyeing process for polyester-cotton blended fabrics, comprising the following steps:

[0009] (1) A hydrophilic liquid phase is obtained by mixing polysiloxane quaternary ammonium salt, alcohol, water, reactive dye and disperse dye;

[0010] (2) Supercritical CO2 fluid is introduced into the reactor and mixed with the hydrophilic liquid phase to dye the polyester-cotton blended fabric;

[0011] (3) Adjust the temperature and / or pressure for finishing;

[0012] (4) Cooling and depressurization to recover CO2, and then dyeing and finishing the fabric;

[0013] The dyeing process involves a reaction vessel with a pressure of 20-30 MPa and a temperature of 80-120°C. Adjusting the temperature refers to setting it to 125-160°C, and adjusting the pressure refers to setting it to 14-18 MPa.

[0014] This invention uses polysiloxane quaternary ammonium salt as an emulsifier, combined with other components to construct a supercritical CO2 microemulsion dyeing system. Benefiting from the weak intermolecular forces of siloxane chains, it exhibits good solubility in scCO2, and under certain conditions, can form a stable microemulsion in scCO2, loading reactive dyes and water for delivery to cotton fibers for dyeing. Because the density of scCO2 varies under different pressures and / or temperatures, its solubility differs, ultimately leading to varying microemulsion stability. By controlling different reaction pressures and / or temperatures during the dyeing and finishing stages, the microemulsion remains stable during dyeing and demulsifies during finishing, thus achieving a one-bath dyeing and finishing process for fabrics. After demulsification, the solubility of the polysiloxane quaternary ammonium salt decreases, causing it to aggregate and tend to adsorb onto the fabric surface, thereby exerting a softening and antibacterial finishing effect.

[0015] In some embodiments, the polysiloxane quaternary ammonium salt contains polysiloxane segments grafted with quaternary ammonium side groups, and the HCB value of the polysiloxane quaternary ammonium salt is 7 to 10; for example, it can be any value among 7, 8, 9, 10 or 7 to 10.

[0016] The HCB value reflects the CO2 philicity and hydrophilicity of polysiloxane quaternary ammonium salts, ranging from 0 to 20, where 20 represents complete hydrophilicity and 0 represents complete CO2 philicity. HCB = (molecular weight of hydrophilic group ÷ (molecular weight of hydrophilic group + molecular weight of CO2-loving group)) × 20. In polysiloxane quaternary ammonium salts, the quaternary ammonium salt groups (and polyether blocks) are hydrophilic groups, while the rest are CO2-loving groups. When the HCB of a polysiloxane quaternary ammonium salt is 7-10, it can form a stable microemulsion in scCO2.

[0017] In some embodiments, the polysiloxane quaternary ammonium salt contains polysiloxane segments grafted with quaternary ammonium side groups, and the number-average molecular weight of the polysiloxane quaternary ammonium salt is 2000~5000 g / mol; for example, it can be any value among 2000, 2500, 3000, 3500, 4000, 4500, 5000 g / mol or 2000~5000 g / mol. The polysiloxane quaternary ammonium salt provides the best finishing effect on fabrics when it meets the above molecular weight range. Below 2000 g / mol, the film-forming property of the polysiloxane quaternary ammonium salt is low; above 5000 g / mol, the polysiloxane quaternary ammonium salt easily aggregates into particles during demulsification, making it difficult to spread and reducing the finishing effect.

[0018] In some embodiments, the polysiloxane quaternary ammonium salt is a polymer containing molecular segments of formula I:

[0019] (Formula I); where R1, R2, and R3 are independently selected from methyl, ethyl, or propyl, and R5 is an alkyl group having 1 to 8 carbon atoms.

[0020] In some embodiments, prior to dyeing, the polyester-cotton blended fabric is immersed in a pretreatment solution and dried, the pretreatment solution comprising an alkanolamine compound and a solvent; the alkanolamine compound is at least one selected from ethanolamine, diethanolamine, triethanolamine, serine, threonine, and tyrosine.

[0021] The purpose of pretreatment is to plasticize cotton fibers. Alkylamine compounds can break the hydrogen bonds on the cellulose molecular chains, increasing the spacing between molecular chains and facilitating the entry of dye molecules during subsequent dyeing. Furthermore, alkylamine compounds can increase the positive charge of cotton fibers, which is beneficial for the adsorption of reactive dyes with negatively charged hydrophilic groups, thereby increasing the dye uptake rate of reactive dyes.

[0022] In some embodiments, the soaking temperature is 40~80°C.

[0023] In some embodiments, the drying temperature is 60-80°C.

[0024] In some embodiments, the solvent is selected from at least one of water, methanol, ethanol, and isopropanol.

[0025] In some embodiments, the percentage content of the alkanolamine compound in the pretreatment solution is 5% to 20%; for example, it can be any value among 5%, 8%, 11%, 14%, 17%, 20% or 5% to 20%. The pretreatment solution that meets the above concentration range has a good effect on the dyeing rate after pretreatment of polyester-cotton blended fabrics. If the concentration is too low, it is difficult to exert the plasticizing effect, and if the concentration is too high, it will cause the fabric to turn yellow.

[0026] In some embodiments, the alcohol includes at least one of n-butanol, n-pentanol, and n-hexanol; the alcohol acts as an auxiliary emulsifier, which is beneficial for stabilizing micelles.

[0027] In some embodiments, the reactive dye is a triazine reactive dye or a vinyl sulfone reactive dye, and the reactive dye contains sulfonic acid groups. Reactive dyes have excellent water solubility due to carrying sulfonate or carboxylate groups, but the sulfonic acid groups are relatively highly polar, which is beneficial for electrostatic attraction with the quaternary ammonium groups in polysiloxane quaternary ammonium salts at high temperatures, thereby assisting the polysiloxane chains to form a film on the fabric surface, thus playing a role in color fixation and finishing. In step (3), the temperature is increased to 125~160℃, the molecular motion and collision are intensified, and the quaternary ammonium groups of polysiloxane quaternary ammonium salts are electrostatically attracted with the sulfonic acid groups, which is beneficial for the polysiloxane quaternary ammonium salts to adsorb and form a film on the fabric surface.

[0028] In some embodiments, the disperse dye is anthraquinone disperse dye, azo disperse dye, or heterocyclic disperse dye.

[0029] In some embodiments, the mass ratio of the polysiloxane quaternary ammonium salt, alcohol, water, reactive dye, disperse dye, and supercritical CO2 fluid is 10~25:15~36:0.2~8:0.02~0.2:0.02~0.2:40~80.

[0030] In some embodiments, the ratio of the total mass of the polyester-cotton blended fabric to the reactive dye and the disperse dye is 100g: 1~2.5g.

[0031] In some embodiments, the polysiloxane quaternary ammonium salt contains polysiloxane segments grafted with quaternary ammonium side groups, and the polysiloxane quaternary ammonium salt further contains polyether blocks. The polyether is a hydrophilic segment that can be used as a hydrophilic unit to adjust the HCB value of the polysiloxane quaternary ammonium salt.

[0032] In some embodiments, the staining time is 30 to 100 minutes.

[0033] In some implementations, the flow rate of the supercritical CO2 fluid is 10~50 g / min.

[0034] In some implementations, the sorting time is 20-40 minutes.

[0035] In some implementations, the cooling and decompression refers to reducing the pressure to 3MPa-8MPa and the temperature to 20℃-50℃, and recovering the hydrophilic liquid phase components and carbon dioxide through a separation vessel.

[0036] The present invention has the following beneficial effects:

[0037] This invention provides a one-bath dyeing process for polyester-cotton blended fabrics. The process uses polysiloxane quaternary ammonium salt as an emulsifier to prepare a supercritical CO2 microemulsion dyeing system. The density of the supercritical CO2 fluid is controlled by adjusting the temperature and / or pressure during the reaction process, thereby causing the microemulsion to form or disintegrate. When a stable microemulsion is formed, the microemulsion loads and delivers reactive dyes to the cotton fibers to achieve dyeing. When the microemulsion disintegrates, the solubility of the polysiloxane quaternary ammonium salt decreases, it aggregates and tends to adsorb onto the fabric surface, thereby exerting a softening and antibacterial finishing effect. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is the result of the antibacterial performance test. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0041] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly indicating the number, specific order, or primary and secondary relationship of the indicated technical features.

[0042] The term "embodiment" in this document means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0043] In the embodiments of this application, the term "or / and" is only a description of the relationship between related objects, indicating that there can be three kinds of relationships. For example, A or / and B can represent three situations: A exists alone, A and B exist at the same time, and B exists alone.

[0044] Additionally, the character " / " in this article generally indicates that the objects before and after it are in an "or" relationship.

[0045] In the embodiments of this application, "multiple" means two or more (including two), similarly, "multiple groups" means two or more (including two groups), and "multiple layers" means two or more (including two layers), unless otherwise explicitly specified and limited.

[0046] In the embodiments of this application, "at least one" means one or more.

[0047] Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0048] The features and performance of the present invention will be further described in detail below with reference to embodiments. Example 1

[0049] The one-bath dyeing process for polyester-cotton blended fabrics includes the following steps:

[0050] (1) Mix polysiloxane quaternary ammonium salt, n-pentanol, water, CI Reactive Red 195 and CI Disperse Red 60, and place the resulting hydrophilic liquid phase in the solvent tank of the supercritical staining system;

[0051] (2) Place the polyester-cotton blended bleached fabric (polyester to cotton mass ratio of 65:35, thread / 10cm, 459×235) in a dyeing kettle and introduce supercritical CO2 fluid for dyeing; wherein, the dyeing pressure is 26MPa, the temperature is 90℃, the time is 100min, and the flow rate of supercritical CO2 fluid is 10g / min.

[0052] (3) Adjust the pressure to 16MPa and the temperature to 140℃, and continue to circulate the liquid phase for 30 minutes for cleaning;

[0053] (4) Reduce the pressure to 5MPa and the temperature to 30℃, and recover the hydrophilic liquid phase components and carbon dioxide through the separation vessel to obtain the dyed and finished fabric.

[0054] The mass ratio of the polysiloxane quaternary ammonium salt, n-pentanol, water, reactive dye, disperse dye, and supercritical CO2 fluid is 18:26:1:0.03:0.03:54.94.

[0055] The ratio of polyester-cotton blended fabric to reactive dyes and disperse dyes is 100g:2g.

[0056] The polysiloxane quaternary ammonium salt has an HCB value of 8.26 and a number-average molecular weight of 3474 g / mol, and has the following structure:

[0057] ,

[0058] The HCB value is calculated in the following way:

[0059] (1) The number-average molecular weight Mn was determined by gel permeation chromatography (GPC) under the following conditions: a Waters 515-2414 gel permeation chromatograph was used for determination, the mobile phase was chloroform, the flow rate was 1 mL / min, the detector temperature was 35℃, the column temperature was 40℃, and the standard was narrow distribution polystyrene (PS).

[0060] (2) Using nuclear magnetic resonance hydrogen spectroscopy (NMR) 1 H-NMR) test repeat unit ratio (x:y) = 1.8; 1 H-NMR δ(D2O, ppm): ① 0.09 (s, Si-(CH3)), ② 0.56 (t, Si-(CH2)), ③ 0.6~1.11 (m, SiCH2-(CH2)), ④ 1.22 (t, CH2-(CH3)), ⑤ 3.14 (d, N-(CH3)), ⑥ 4.52 (m, N-(CH2)); The calculation process is as follows: Let A be the total area of ​​the proton peaks corresponding to Si-CH, which is the sum of the integrated areas of ① and ② in the NMR spectrum; let B be the total area of ​​the proton peaks corresponding to N-CH, which is the sum of the integrated areas of ⑤ and ⑥ in the NMR spectrum; then the following relationship is established: Therefore, x:y = 1.8.

[0061] (3) The value of y is 9.35 by calculating Mn and (x:y); the calculation process is as follows: 74x+209.79y+162.09=Mn, x / y=1.8, solve the two linear equations to get y=9.35.

[0062] HCB = Hydrophilic group molecular weight ÷ (Hydrophilic group molecular weight + CO2-philic group molecular weight) × 20

[0063] The hydrophilic group is N(CH3)2C2H5Cl, and the remaining segments are CO2-loving groups.

[0064] HCB=108.59y / (Mn-108.59y)×20=108.59×9.35 / (3474-108.59×9.35)×20=8.26

[0065] The preparation method of polysiloxane quaternary ammonium salt is as follows:

[0066] (1) Tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, hexamethyldisiloxane, and Purolite CT-175 resin were stirred to make them evenly mixed, and the temperature was slowly raised to 80°C. The mixture was reacted for 12 hours, filtered, and distilled under reduced pressure to obtain chloropropyl polysiloxane; wherein the molar ratio of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane was 2.4:4.3:1, and the amount of Purolite CT-175 resin added was 5% of the total mass of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane;

[0067] (2) The prepared chloropropyl polysiloxane was dissolved in n-butanol, and then N,N-dimethylethylamine was added and refluxed at 100°C under nitrogen protection for 72 h. After the reaction was completed, the polysiloxane quaternary ammonium salt was obtained by vacuum distillation. Chloropropyl polysiloxane and N,N-dimethylethylamine were fed in a ratio of 1:1.2 of the molar amount of chloropropyl to N,N-dimethylethylamine. Example 2

[0068] The difference from Example 1 is that the polyester-cotton blended bleached fabric is first pretreated to obtain a pretreated fabric, and then the pretreated fabric is placed in a dyeing kettle for step (2); the pretreatment steps are as follows:

[0069] The polyester-cotton blended bleached fabric was immersed in an 8wt% triethanolamine aqueous solution at a liquor ratio of 1:20 for 1 hour. After immersion, the fabric was removed, rolled, and dried at 80°C to obtain the pretreated fabric. Example 3

[0070] The difference from Example 1 is that the polysiloxane quaternary ammonium salt is replaced with a polysiloxane quaternary ammonium salt with an HCB value of 6.45 and a number-average molecular weight of 3408 g / mol.

[0071] The preparation method of the polysiloxane quaternary ammonium salt differs from that in Example 1 in that the molar ratio of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane is 2:4.5:1. Example 4

[0072] The difference from Example 1 is that the polysiloxane quaternary ammonium salt is replaced with a polysiloxane quaternary ammonium salt with an HCB value of 7.21 and a number-average molecular weight of 3214 g / mol.

[0073] The preparation method of polysiloxane quaternary ammonium salt differs from that in Example 1 in that the molar ratio of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane is 2.2:4.6:1. Example 5

[0074] The difference from Example 1 is that the polysiloxane quaternary ammonium salt is replaced with a polysiloxane quaternary ammonium salt with an HCB value of 9.99 and a number-average molecular weight of 3374 g / mol.

[0075] The preparation method of polysiloxane quaternary ammonium salt differs from that in Example 1 in that the molar ratio of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane is 2.6:4.7:1. Example 6

[0076] The difference from Example 1 is that the polysiloxane quaternary ammonium salt is replaced with a polysiloxane quaternary ammonium salt with an HCB value of 10.95 and a number-average molecular weight of 3542 g / mol.

[0077] The preparation method of polysiloxane quaternary ammonium salt differs from that in Example 1 in that the molar ratio of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane is 3:4.5:1. Example 7

[0078] The difference from Example 1 is that the polysiloxane quaternary ammonium salt is replaced with a polysiloxane quaternary ammonium salt with an HCB value of 8.51 and a number-average molecular weight of 1765 g / mol.

[0079] The preparation method of polysiloxane quaternary ammonium salt differs from that in Example 1 in that the molar ratio of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane is 1.3:2.1:1. Example 8

[0080] The difference from Example 1 is that the polysiloxane quaternary ammonium salt is replaced with a polysiloxane quaternary ammonium salt with an HCB value of 8.54 and a number-average molecular weight of 2104 g / mol.

[0081] The preparation method of polysiloxane quaternary ammonium salt differs from that in Example 1 in that the molar ratio of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane is 1.5:2.9:1. Example 9

[0082] The difference from Example 1 is that the polysiloxane quaternary ammonium salt is replaced with a polysiloxane quaternary ammonium salt with an HCB value of 8.25 and a number-average molecular weight of 4874 g / mol.

[0083] The preparation method of polysiloxane quaternary ammonium salt differs from that in Example 1 in that the molar ratio of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane is 3.3:6.5:1. Example 10

[0084] The difference from Example 1 is that the polysiloxane quaternary ammonium salt is replaced with a polysiloxane quaternary ammonium salt with an HCB value of 8.36 and a number-average molecular weight of 5841 g / mol.

[0085] The preparation method of polysiloxane quaternary ammonium salt differs from that in Example 1 in that the molar ratio of tetramethyltetra(3-chloropropyl)cyclotetrasiloxane, octamethylcyclotetrasiloxane, and hexamethyldisiloxane is 4.1:8:1. Example 11

[0086] The difference from Example 2 is that the pretreatment solution is an 8 wt% ethanolic ethanol solution of ethanolamine. Example 12

[0087] The difference from Example 2 is that the pretreatment solution is an 8 wt% aqueous solution of serine. Example 13

[0088] The difference from Example 1 is that in step (3), the pressure is adjusted to 16 MPa, the temperature remains unchanged, and the liquid phase continues to circulate for 30 minutes for finishing. Example 14

[0089] The one-bath dyeing process for polyester-cotton blended fabrics includes the following steps:

[0090] (1) Mix polysiloxane quaternary ammonium salt (same as in Example 1), n-butanol, water, CI active yellow 145, and CI dispersible yellow 114, and place the resulting hydrophilic liquid phase in the solvent tank of the supercritical staining system;

[0091] (2) The polyester-cotton blended bleached fabric (polyester to cotton mass ratio of 65:35, thread / 10cm, 459×235) was soaked in a 12wt% triethanolamine aqueous solution with a bath ratio of 1:20. After soaking for 1 hour, it was taken out, rolled and then dried at 80℃ to obtain the pretreated fabric.

[0092] (3) Place the pretreated fabric in a dyeing kettle and introduce supercritical CO2 fluid for dyeing; wherein the dyeing pressure is 20MPa, the temperature is 100℃, the time is 90min, and the flow rate of supercritical CO2 fluid is 20g / min.

[0093] (4) Adjust the pressure to 14MPa and the temperature to 160℃, and continue to circulate the liquid phase for 20 minutes for cleaning;

[0094] (5) Reduce the pressure to 5MPa and the temperature to 30℃, and recover the hydrophilic liquid phase components and carbon dioxide through the separation vessel to obtain the dyed and finished fabric.

[0095] The mass ratio of the polysiloxane quaternary ammonium salt, n-pentanol, water, reactive dye, disperse dye, and supercritical CO2 fluid is 25:15:8:0.2:0.2:51.6.

[0096] The ratio of polyester-cotton blended fabric to reactive dyes and disperse dyes is 100g:2.5g. Example 15

[0097] The one-bath dyeing process for polyester-cotton blended fabrics includes the following steps:

[0098] (1) Mix polysiloxane quaternary ammonium salt (same as in Example 1), n-hexanol, water, CI Reactive Blue 19, CI Disperse Blue 367, and place the resulting hydrophilic liquid phase in the solvent tank of the supercritical staining system;

[0099] (2) The polyester-cotton blended bleached fabric (polyester to cotton mass ratio of 65:35, thread / 10cm, 459×235) was soaked in a 20wt% triethanolamine aqueous solution with a bath ratio of 1:20. After soaking for 1 hour, it was taken out, rolled and dried at 80℃ to obtain the pretreated fabric.

[0100] (3) Place the pretreated fabric in a dyeing kettle and introduce supercritical CO2 fluid for dyeing; wherein the dyeing pressure is 30MPa, the temperature is 80℃, the time is 60min, and the flow rate of supercritical CO2 fluid is 40g / min.

[0101] (4) Adjust the pressure to 18MPa and the temperature to 130℃, and continue to circulate the liquid phase for 40 minutes for cleaning;

[0102] (5) Reduce the pressure to 5MPa and the temperature to 30℃, and recover the hydrophilic liquid phase components and carbon dioxide through the separation vessel to obtain the dyed and finished fabric.

[0103] The mass ratio of the polysiloxane quaternary ammonium salt, n-pentanol, water, reactive dye, disperse dye, and supercritical CO2 fluid is 10:36:0.2:0.1:0.1:53.6.

[0104] The ratio of polyester-cotton blended fabric to reactive dyes and disperse dyes is 100g:1g.

[0105] Comparative Example 1

[0106] The polysiloxane quaternary ammonium salt in Example 1 was replaced with an equal mass of fatty alcohol polyoxyethylene ether (AEO-9), and everything else was the same as in Example 1.

[0107] Comparative Example 2

[0108] The polysiloxane quaternary ammonium salt in Example 1 was replaced with an equal mass of polysiloxane polyether block copolymer, and everything else was the same as in Example 1.

[0109] The polysiloxane-polyether block copolymer was purchased from DIGIC, Germany. The polysiloxane-polyether block copolymer had an HCB value of 8.32 and a number-average molecular weight of 7422 g / mol, and possessed the following structure:

[0110]

[0111] The HCB value is calculated in the following way:

[0112] (1) The number-average molecular weight Mn was determined by gel permeation chromatography (GPC) under the following conditions: a Waters 515-2414 gel permeation chromatograph was used for determination, the mobile phase was chloroform, the flow rate was 1 mL / min, the detector temperature was 35℃, the column temperature was 40℃, and the standard was narrow distribution polystyrene (PS).

[0113] (2) Using nuclear magnetic resonance hydrogen spectroscopy (NMR) 1 H-NMR) test repeat unit ratio (x:y) = 1.8; 1 H-NMRδ (CDCl3, ppm): ① 0.08~0.1 (Si-(CH3)), ④ 3.5~4.5 (O-(CH2CH2)); The calculation process is as follows: Let A be the total area of ​​the proton peaks corresponding to Si-CH, which is the sum of the integrated areas of ① in the NMR spectrum. Let B be the total area of ​​the proton peaks corresponding to (CH2CH2O) in the polyether segment repeating unit, which is the sum of the integrated areas of ② in the NMR spectrum. Then the following relationship is listed: Therefore, x:y = 1.38.

[0114] (3) The value of y is approximately 49.55, calculated using Mn and (x:y).

[0115] HCB = Hydrophilic group molecular weight ÷ (Hydrophilic group molecular weight + CO2-philic group molecular weight) × 20

[0116] The hydrophilic group is N(CH3)2C2H5Cl, and the rest are CO2-loving groups.

[0117] HCB=44y / (Mn-44y)×20=44×49.55 / (7422-44×49.55)×20=8.32

[0118] Comparative Example 3

[0119] The polysiloxane quaternary ammonium salt in Example 1 was replaced with an equal mass of amino silicone oil, and everything else was the same as in Example 1. The amino silicone oil was Dow Corning OFX-8040A.

[0120] Comparative Example 4

[0121] The difference from Example 1 is that step (3) is omitted and the staining time in step (2) is 130 min.

[0122] Test Example 1: Apparent Color Depth Test

[0123] The test method for apparent color depth (K / S value) is as follows: A Datacolor 650 computer colorimeter was used, with a D65 light source and a 10° viewing angle. The K / S value at the maximum absorption wavelength of the fabric was measured. Each sample was measured at 10 different locations, and the average value was taken as the apparent color depth of the sample. The results are listed in Table 1.

[0124] Test Example 2: Colorfastness Test

[0125] Color fastness to rubbing: Tested in accordance with GB / T3920-2008 "Textiles - Tests for color fastness to rubbing".

[0126] Color fastness to washing with soap: Tested in accordance with GB / T3921-2008 "Textiles - Tests for color fastness to washing with soap".

[0127] The results are listed in Table 1. Table 1

[0128]

[0129] As shown in Table 1, the dyed fabrics obtained in Example 1 and Comparative Examples 1-3 have higher K / S values ​​and color fastness, indicating that the polysiloxane quaternary ammonium salt provided by this invention can improve the solubility of reactive dyes in scCO2 compared to AEO-9, polysiloxane polyether block copolymers, and amino silicone oil, i.e., it has better emulsification ability; moreover, the polysiloxane quaternary ammonium salt can provide a certain color-fixing effect during finishing, which is due to the bonding between the quaternary ammonium and reactive dyes at high temperatures. Compared with Example 1, Comparative Example 4 has lower color fastness, indicating that without adjusting the dyeing kettle pressure and / or temperature for finishing, the polysiloxane quaternary ammonium salt cannot finish the fabric surface and exert a color-fixing effect. Compared with Example 2, no pretreatment was performed in Example 1. In Example 2, the pretreatment resulted in higher cotton fiber shaping, which is conducive to dye uptake, thus resulting in a higher color depth. Compared with Examples 3-6, Examples 1 shows that the HCB value of the polysiloxane quaternary ammonium salt affects the dyeing performance. An excessively high or low HCB value is detrimental to the formation of a stable microemulsion for dye loading, thus hindering dye uptake. Compared with Examples 7-10, Examples 1 shows that the molecular weight of the polysiloxane quaternary ammonium salt affects the dyeing performance. An excessively high or low molecular weight is detrimental to the formation of a stable microemulsion for dye loading, thus hindering dye uptake. Compared with Examples 11-12, Examples 1 shows that the components of the pretreatment solution used in the pretreatment process affect the pretreatment effect. Specifically, the ability to improve dye uptake ranks as follows: triethanolamine > ethanolamine > serine. This is related to the basicity and the number of hydroxyl groups in the amine compound. Stronger basicity is more conducive to dye adsorption and uptake, and a greater number of hydroxyl groups results in a stronger plasticizing effect on cotton fibers. Comparing Example 1 and Example 13, Example 13 only reduced the pressure during the finishing stage without raising the temperature, resulting in lower color fastness compared to Example 1. This is because raising the temperature is beneficial for the electrostatic adsorption of sulfonic acid groups of quaternary ammonium and reactive dyes, thereby playing a color-fixing role.

[0130] Test Example 3: Antibacterial Test

[0131] The tests were conducted according to GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles - Part 3: Vibration method", and the results are listed in Table 2. (Appendix) Figure 1 The plates used in the antibacterial tests of Examples 1 and Comparative Examples 1-3 contain Staphylococcus aureus colonies.

[0132] Test Example 4: Style Test

[0133] Surface friction properties: The tests were conducted on an automatic surface tester in accordance with FZ / T 01054—2012 "Test Methods for Surface Friction Properties of Fabrics".

[0134] Bending stiffness: Refer to ZB W 04003—87 "Test Method for Fabric Stiffness - Inclined Cantilever Method" and test on an automatic fabric stiffness tester.

[0135] Smoothness and softness were evaluated using the average coefficient of dynamic friction and bending stiffness, respectively, and the results are listed in Table 2.

[0136] Table 2

[0137]

[0138] As shown in Table 2, the dyed fabrics provided in the embodiments of the present invention have antibacterial properties. Comparative Example 4 showed no antibacterial effect, and the resulting fabric had a rough and stiff hand feel, indicating that without adjusting the dyeing kettle pressure and / or temperature for finishing, the polysiloxane quaternary ammonium salt could not finish the fabric surface and exert its antibacterial effect. From Examples 1, 4-5, and 8-9, it can be seen that the HCB value and molecular weight of the polysiloxane quaternary ammonium salt affect its finishing effect. Specifically, the higher the HCB value, the higher the antibacterial effect, but the worse the hand feel; the higher the molecular weight, the less significant the change in antibacterial effect, but the better the hand feel.

[0139] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A one-bath dyeing process for polyester-cotton blended fabrics, characterized in that, Includes the following steps: (1) A hydrophilic liquid phase is obtained by mixing polysiloxane quaternary ammonium salt, alcohol, water, reactive dye and disperse dye; (2) Supercritical CO2 fluid is introduced into the reactor and mixed with the hydrophilic liquid phase to dye the polyester-cotton blended fabric; (3) Adjust the temperature and pressure for finishing; (4) Cooling and depressurization to recover CO2, and then dyeing and finishing the fabric; The dyeing process involves a reaction vessel with a pressure of 20-30 MPa and a temperature of 80-120°C; the temperature adjustment refers to adjusting the temperature to 125-160°C, and the pressure adjustment refers to adjusting the pressure to 14-18 MPa. The polysiloxane quaternary ammonium salt is a polymer containing molecular segments of the following formula I: (Formula I); In the formula, R1, R2, and R3 are independently selected from methyl, ethyl, or propyl, and R5 is an alkyl group having 1 to 8 carbon atoms; The HCB value of the polysiloxane quaternary ammonium salt is 7~10; The number-average molecular weight of the polysiloxane quaternary ammonium salt is 2000~5000 g / mol; The reactive dye is a triazine type reactive dye or a vinyl sulfone type reactive dye, and the reactive dye contains a sulfonic acid group; the disperse dye is an anthraquinone type disperse dye, an azo type disperse dye, or a heterocyclic type.

2. The one-bath dyeing process for polyester-cotton blended fabrics according to claim 1, characterized in that, Before dyeing, the polyester-cotton blended fabric is soaked in a pretreatment solution and dried. The pretreatment solution includes an alcoholic amine compound and a solvent. The alcoholic amine compound is at least one of ethanolamine, diethanolamine, triethanolamine, serine, threonine, and tyrosine.

3. The one-bath dyeing process for polyester-cotton blended fabrics according to claim 2, characterized in that, The soaking temperature is 40~80℃; And / or, the drying temperature is 60~80℃; And / or, the solvent is selected from at least one of water, methanol, ethanol and isopropanol; And / or, the percentage content of the alkanolamine compound in the pretreatment solution is 5% to 20%.

4. The one-bath dyeing process for polyester-cotton blended fabrics according to claim 1, characterized in that, The alcohol includes at least one of n-butanol, n-pentanol, and n-hexanol.

5. The one-bath dyeing process for polyester-cotton blended fabrics according to claim 1, characterized in that, The mass ratio of the polysiloxane quaternary ammonium salt, alcohol, water, reactive dye, disperse dye, and supercritical CO2 fluid is 10~25:15~36:0.2~8:0.02~0.2:0.02~0.2:40~80; And / or, the ratio of the total mass of the polyester-cotton blended fabric to the reactive dye and the disperse dye is 100g: 1~2.5g.

6. The one-bath dyeing process for polyester-cotton blended fabrics according to any one of claims 1, characterized in that, The polysiloxane quaternary ammonium salt also contains polyether blocks.

7. The one-bath dyeing process for polyester-cotton blended fabrics according to claim 1, characterized in that, The staining time is 30-100 minutes; And / or, the flow rate of the supercritical CO2 fluid is 10~50 g / min; And / or, the sorting time is 20~40 minutes.

8. The one-bath dyeing process for polyester-cotton blended fabrics according to claim 1, characterized in that, The cooling and decompression refers to reducing the pressure to 3MPa-8MPa and the temperature to 20℃-50℃.

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