Modified dye and application thereof

Abstract

The invention discloses a modified dye and application thereof, and a preparation method of the modified dye comprises the following steps: reacting a disperse dye with a tertiary nitrogen structure with a compound as shown in a formula (I) under an alkaline condition to generate the modified dye, wherein the pH value of the alkaline condition is controlled to be greater than or equal to 10; in the # imgabs0 # formula (I), R1 is selected from C1-3 alkylene or hydroxyl-substituted C1-3 alkylene, and R2, R3 and R4 are independently selected from C1-2 alkyl; two quaternary ammonium centers spaced by R1 are formed in molecules of the modified dye; the modified dye provided by the invention can realize stock solution coloring and functionalization at the same time, almost has no negative influence on physical properties of a product, is free of wastewater discharge, meets the current high-standard requirement of environmental protection, and is suitable for industrial production. The problems that part of existing antibacterial agents are insufficient in high-temperature stability after being added, unexpected effects can be generated with disperse dyes, and even part of the antibacterial agents are difficult to disperse effectively are solved, and the antibacterial effect is good and lasting.

Description

[0001] This invention is a divisional application of the Chinese invention patent application with the application date of August 13, 2024, application number 2024111028362, and name “A nonwoven fabric, antibacterial masterbatch, and antibacterial colored fiber”. Technical Field

[0002] The invention relates to the technical field of textile manufacturing, and in particular to a modified dye and application thereof. Background Art

[0003] Textiles inevitably need to have a certain color when they are used, and different colors may be required in different scenarios. At the same time, with the continuous improvement of ecological and environmental protection requirements and the process of industrial upgrading, the application prospects and industrial scale of biodegradable polyester textiles are getting bigger and bigger, and functional biodegradable polyester textiles are even more popular. For example, biodegradable polyester textiles with antibacterial, flame retardant and other functions have ushered in rapid development. At present, the preparation methods of colored textiles or functionalized biodegradable polyester textiles mainly include the following methods: the first method: first prepare colored or functionalized fibers, and then make colored or functionalized textiles with the colored or functionalized fibers, and the color or functionalization imparting methods include solution coloring or functionalization, and fiber dyeing or functionalization, wherein the solution coloring or functionalization is to add dyes or functional additives during the process of fiber formation, that is, directly add dyes or functional additives to the polymer during the spinning process, so that the final fiber itself has color or functionality, and the fiber dyeing or functionalization is the process of dyeing or functionalization after the fiber has been formed, which means that the fiber is impregnated with a dyeing liquid or a functional additive dispersion to achieve dyeing or functionalization; the second method: first make the textile, and then dye it with a dyeing liquid or a functional additive dispersion; of the two methods, the method of dyeing or functionalization with a dyeing liquid or a functional additive dispersion will bring more wastewater and pollution, while the solution coloring or functionalization can be dyed or functionalized without generating wastewater, so it has environmental advantages, and also has the effect of energy saving and emission reduction.

[0004] At present, based on the needs of ecological and environmental protection, it is preferred to use the method of solution coloring or functionalization; however, when it is desired to prepare biodegradable polyester textiles that have both color and antibacterial functions, it is necessary to simultaneously add the masterbatch containing the dye and the antibacterial agent to the biodegradable polyester raw material such as biodegradable polytrimethylene terephthalate (PTT) and polybutylene succinate (PBS), melt-spin them together, make them into fibers or yarns, and then make them into textiles. However, it has been found in practice that the above method has the following problems: (1) Some antibacterial agents (such as organic antibacterial agents) have insufficient high temperature stability and decompose when melted together with the polyester raw material, thus losing their antibacterial efficacy. Some antibacterial agents also have (1) The antimicrobial agent interacts with the disperse dyes, destroying the antibacterial effect. In addition, the antimicrobial agent (such as inorganic antimicrobial agent) is not well dispersed in the polyester raw material and is easy to agglomerate, resulting in the antibacterial effect not meeting the expectations, especially when the antimicrobial performance requirements are high and the amount of antimicrobial agent added is too much; (2) The color difference is large and the color fastness is poor. Analysis shows that after the addition of some antimicrobial agents, the stability of the dye is affected by the action of environmental oxygen, light, etc., causing the dye to decompose or reduce adhesion; (3) The addition of antimicrobial agents causes a decrease in the physical properties of the fiber, such as strength, elongation, feel, etc. Some antimicrobial agents affect the interaction between the resin polymer molecular chains, affecting the crystallinity and orientation of the fiber, thereby affecting the physical properties of the fiber. Summary of the invention

[0005] The object of the present invention is to overcome one or more deficiencies in the prior art and to provide an improved nonwoven fabric having almost no negative impact on the physical properties of the product while imparting color and antibacterial properties to the nonwoven fabric and a method for preparing the same.

[0006] The present invention also provides antibacterial masterbatch or antibacterial colored fiber which can be used to prepare the nonwoven fabric.

[0007] In order to achieve the above object, a technical solution adopted by the present invention is:

[0008] A nonwoven fabric, comprising a nonwoven structure made of antibacterial colored fibers through a nonwoven process;

[0009] The method for preparing the antibacterial colored fiber comprises: reacting a disperse dye having a tertiary nitrogen structure with a compound represented by formula (I) under alkaline conditions to generate a modified dye; wherein the pH value of the alkaline conditions is controlled to be greater than or equal to 10;

[0010] Then, the modified dye and the first polyester resin are mixed and melt-extruded to prepare an antibacterial masterbatch;

[0011] The antibacterial masterbatch is mixed with a second polyester resin, and subjected to a spinning process to prepare the antibacterial colored fiber in a staple form;

[0012] In which R1 is selected from C 1-3 Alkyl or hydroxy substituted C 1-3 Alkyl, R2, R3, R4 are independently selected from C 1-2 alkyl.

[0013] In some embodiments of the present invention, the nonwoven process can be carried out with reference to the existing nonwoven process. Further, the nonwoven process includes opening, feeding, carding, laying, needling, gluing, shaping and rolling in sequence.

[0014] Furthermore, the specific operations of each step in the above nonwoven process are as follows:

[0015] Opening: Sawtooth roller opener, beater speed 400-700 rpm; Feeding: Sawtooth roller speed 5-25 rpm, flap roller speed 5-30 rpm; Carding: Fiber web longitudinal and transverse strength ratio 5-10:1; Laying: Width 2.5-4.5m, web forming machine running 150-250m / min; Needling: Needling depth 8-16mm, needling density 70-150 needles / cm 2 ; Gluing: Use polyester hot melt adhesive, mix the polyester hot melt adhesive with pure water in a mass ratio of 1:0.9-1.1, stir at high speed to form a slurry, and then coat it on the fiber web by a coating equipment, and hot press at 145-155°C and 0.05-0.15MPa. Furthermore, the hot pressing time is 3-8s; Shaping: The heat setting temperature is 140-155°C, and the time is 30-60s; Rolling: The winding speed is 150-250m / min.

[0016] Further, in terms of mass percentage, the raw materials of the polyester hot melt adhesive include: 67%-72% PES copolyester powder, 13%-16% ethylene methacrylate glycidyl copolymer, 13%-16% ethylene vinyl acetate copolymer, and 0.1%-1% antioxidant. According to a specific aspect of the present invention, in terms of mass percentage, the raw materials of the polyester hot melt adhesive include: 69.5% PES copolyester powder, 15% ethylene methacrylate glycidyl copolymer, 15% ethylene vinyl acetate copolymer, and 0.5% antioxidant MIANOX616.

[0017] According to some preferred aspects of the present invention, the disperse dye having a tertiary nitrogen structure has the following structure:

[0018]

[0019] According to some preferred aspects of the present invention, the modified dye has the following structure:

[0020]

[0021] In some embodiments of the present invention, the disperse dye having a tertiary nitrogen structure includes, but is not limited to, a combination of one or more selected from the following compounds:

[0022]

[0023] In some embodiments of the present invention, in formula (I), R1 is selected from methyl, ethyl, propyl, hydroxy-substituted methyl, hydroxy-substituted ethyl or hydroxy-substituted propyl.

[0024] In some embodiments of the present invention, in formula (I), R2, R3, and R4 are independently selected from methyl.

[0025] In some embodiments of the present invention, the compound represented by formula (I) is selected from (2-chloroethyl)trimethylammonium chloride (structural formula: ), (3-chloropropyl) trimethylammonium chloride, (3-chloro-2-hydroxypropyl) trimethylammonium chloride (structural formula: ) or a combination of one or more thereof.

[0026] According to some preferred aspects of the present invention, the feed mass ratio of the disperse dye having a tertiary nitrogen structure to the compound represented by formula (I) is 1-10:1.

[0027] According to some preferred aspects of the present invention, the reaction is controlled to be carried out at 20-30°C.

[0028] According to some preferred aspects of the present invention, the implementation method of preparing the modified dye includes: dissolving the disperse dye having a tertiary nitrogen structure in anhydrous ethanol to prepare a dye solution, and then adding the compound represented by formula (I) to the dye solution to obtain a pre-reaction solution; then adjusting the pH value of the pre-reaction solution to greater than or equal to 10 with an alkaline hydroxide aqueous solution, reacting, and continuously adding the alkaline hydroxide aqueous solution during the reaction to maintain the pH value always greater than or equal to 10.

[0029] Furthermore, in some embodiments of the present invention, the mass concentration of the dye solution is controlled to be 0.5%-5%, and further 0.8%-3%.

[0030] Furthermore, in some embodiments of the present invention, the molar concentration of the alkaline hydroxide aqueous solution is controlled to be 0.5-3 mol / L.

[0031] Further, in some embodiments of the present invention, the alkaline hydroxide in the alkaline hydroxide aqueous solution is sodium hydroxide and / or potassium hydroxide, and the alkaline hydroxide aqueous solution is formed by dispersing the alkaline hydroxide in water.

[0032] Furthermore, in some embodiments of the present invention, the reaction time is controlled to be greater than or equal to 10 minutes. Furthermore, the reaction time is controlled to be 12-90 minutes.

[0033] Furthermore, in some embodiments of the present invention, after the reaction is completed, the pH value is adjusted to 7.0±0.2 using hydrochloric acid, and then the ethanol is removed by evaporation under reduced pressure.

[0034] According to some preferred aspects of the present invention, in the antibacterial masterbatch, the modified dye accounts for 5%-25%, and the first polyester resin accounts for 75%-95%, calculated by mass percentage.

[0035] According to some preferred aspects of the present invention, in the antibacterial colored fiber, the antibacterial masterbatch accounts for 1%-10%, and the second polyester resin accounts for 90%-99%, calculated by mass percentage.

[0036] In some embodiments of the present invention, the first polyester resin and the second polyester resin are independently polytrimethylene terephthalate and / or polybutylene succinate.

[0037] In the present invention, the first polyester resin and the second polyester resin are preferably bio-based polyester resins, which are biodegradable and environmentally friendly. In some embodiments of the present invention, the first polyester resin and the second polyester resin are independently bio-based polytrimethylene terephthalate and / or bio-based polybutylene succinate.

[0038] In some embodiments of the present invention, the spinning process can be carried out by referring to the existing method for making short fibers. Further, the spinning process includes the following steps in sequence: pre-baking, melting, extrusion, cooling, bundling and oiling, drawing, cutting and heat setting.

[0039] Furthermore, the pre-baking temperature is 100-130° C. and the time is 10-30 hours.

[0040] Furthermore, the melting temperature is 240-270°C.

[0041] Furthermore, the extrusion is screw extrusion, and the parameters are: the main screw extrusion temperature is 240-255° C., and the extrusion pressure is 6.5-7.2 MPa.

[0042] Furthermore, the cooling is annular air cooling, and the parameters are: wind speed 0.4-0.6 m / s, wind temperature 25-28° C., and relative humidity controlled at 65%-85%.

[0043] Furthermore, the parameters of the bundle oiling are: oiling amount 0.3%-0.8% (in terms of fiber mass percentage).

[0044] Furthermore, the drawing parameters are: drawing multiple 3-4 times, drawing temperature 65-70°C, and drawing speed 800-1200m / min.

[0045] Furthermore, the cutting is to cut the long fibers into short fibers of 35-40 mm.

[0046] Furthermore, the heat setting parameters are: heat setting temperature 150-160° C., time 20-40 s.

[0047] Another technical solution provided by the present invention is a method for preparing a nonwoven fabric, the method comprising:

[0048] (1) Preparation of modified dyes

[0049] The disperse dye having a tertiary nitrogen structure is reacted with the compound represented by formula (I) under alkaline conditions to generate a modified dye; wherein the pH value of the alkaline conditions is controlled to be greater than or equal to 10;

[0050] (2) Preparation of antibacterial masterbatch

[0051] The modified dye and the first polyester resin are mixed and melt-extruded to prepare an antibacterial masterbatch;

[0052] (3) Preparation of antibacterial colored fibers in short fiber form

[0053] The antibacterial masterbatch is mixed with a second polyester resin, and subjected to a spinning process to obtain an antibacterial colored fiber in a staple form;

[0054] (4) Preparation of nonwoven fabric

[0055] The antibacterial colored fiber is used to prepare nonwoven fabric through a nonwoven process.

[0056] Another technical solution provided by the present invention is an antibacterial masterbatch, wherein the raw materials of the antibacterial masterbatch include a modified dye and a first polyester resin, wherein the antibacterial masterbatch is obtained by mixing and melt-extruding the raw materials;

[0057] The preparation method of the modified dye comprises: reacting a disperse dye having a tertiary nitrogen structure with a compound represented by formula (I) under alkaline conditions to generate a modified dye; wherein the pH value of the alkaline conditions is controlled to be greater than or equal to 10;

[0058] In which R1 is selected from C 1-3 Alkyl or hydroxy substituted C 1-3 Alkyl, R2, R3, R4 are independently selected from C1-2 alkyl.

[0059] Another technical solution provided by the present invention is an antibacterial colored fiber, which is prepared by the following preparation method: the antibacterial masterbatch described above is mixed with a second polyester resin, and the mixture is spun to form the antibacterial colored fiber in the form of short fibers.

[0060] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0061] The present invention is based on the defects of insufficient antibacterial performance, large color difference, decreased physical properties, etc. that exist when preparing textiles with both color and antibacterial functions. The present invention innovatively provides an improved non-woven fabric that has almost no negative impact on the physical properties of the product on the basis of simultaneously giving the non-woven fabric color and antibacterial properties. Specifically, the present invention chemically modifies the disperse dye with a tertiary nitrogen structure for the first time, so that one dye molecule forms two quaternary ammonium centers separated by alkyl groups. Generally, the quaternary ammonium cation plays an antibacterial and bactericidal role by electrostatically interacting with the negatively charged bacterial cell membrane and affecting the function of the bacterial cell membrane. Practice shows that the presence of the quaternary ammonium cation in this form of the present invention has an unexpectedly excellent effect on the antibacterial effect. In particular, the present invention introduces a quaternary ammonium center with antibacterial function into the disperse dye, which not only does not affect the disperse dye, but also avoids the problem that some existing antibacterial agents have insufficient high-temperature stability after addition, will have unexpected effects with the disperse dye, and even some antibacterial agents are difficult to effectively disperse. The present invention can simultaneously achieve the coloring of the original solution and the imparting of functionality, reduce wastewater discharge, meet the current high standards for environmental protection, be conducive to industrial application, and have a long-lasting antibacterial effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 The antibacterial effect diagram of the modified dye prepared in Examples 1-4 of the present invention;

[0063] Figure 2 The antibacterial effect diagram of the modified dye prepared in Comparative Examples 1 and 2 of the present invention;

[0064] Figure 3 This is a diagram showing the antibacterial effect of the nonwoven fabric prepared in Comparative Example 2 of the present invention;

[0065] Figure 4 This is a diagram showing the antibacterial effect of the modified dye prepared in Comparative Example 3 of the present invention;

[0066] Figure 5 This is a diagram showing the antibacterial effect of the nonwoven fabric prepared in Comparative Example 3 of the present invention. DETAILED DESCRIPTION

[0067] The above scheme is further described below in conjunction with specific embodiments; it should be understood that these embodiments are used to illustrate the basic principles, main features and advantages of the present invention, and the present invention is not limited to the scope of the following embodiments; the implementation conditions adopted in the embodiments can be further adjusted according to specific requirements, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0068] Unless otherwise specified in the following examples, all raw materials can be purchased from commercial sources or prepared by conventional methods in the art.

[0069] In the following, (2-chloroethyl)trimethylammonium chloride (CAS No.: 999-81-5) and (3-chloro-2-hydroxypropyl)trimethylammonium chloride (CAS No.: 3327-22-8) were purchased from Hubei Jiufenglong Chemical Co., Ltd. 2-Dimethylaminoethyl chloride hydrochloride (CAS No.: 4584-46-7) was purchased from Hubei Dali Chemical Co., Ltd.

[0070] Disperse Yellow 49 dye, the structural formula is:

[0071] Disperse Red 1 dye, the structural formula is:

[0072] Disperse blue 148 dye, structural formula:

[0073] Disperse Orange 25 dye, structural formula: The above dyes are all commercially available.

[0074] Bio-based PTT resin is produced by our company; PES copolyester powder, brand WT-51, Jiangyin Weitao Plastic New Materials Co., Ltd.; ethylene methacrylate glycidyl ester copolymer, brand AX8750, Shanghai Chaoqi Plastic Chemical Co., Ltd.; ethylene vinyl acetate copolymer, brand UE647-04, Shanghai Chaoqi Plastic Chemical Co., Ltd.

[0075] Embodiment 1:

[0076] This example provides a method for preparing a nonwoven fabric and a nonwoven fabric made therefrom, the preparation method comprising:

[0077] (1) Preparation of modified dye: Dissolve Disperse Yellow 49 dye in anhydrous ethanol to prepare a dye solution with a mass fraction of 2%, and add (2-chloroethyl) trimethylammonium chloride to the above dye solution at a disperse yellow 49 / (2-chloroethyl) trimethylammonium chloride dry weight ratio of 4:1 to obtain a pre-reaction solution. Then adjust the pH value of the pre-reaction solution to 12.0 with a 1 mol / L aqueous sodium hydroxide solution, and continue to drip it during the reaction to maintain the pH value. React at room temperature for 30 minutes. After the reaction is completed, adjust the pH value to 7.0±0.2 with 1 mol / L hydrochloric acid, and finally remove the ethanol by reduced pressure evaporation at 50°C to obtain a modified dye;

[0078] The reaction formula of Disperse Yellow 49 and (2-chloroethyl)trimethylammonium chloride is as follows:

[0079]

[0080] (2) Preparation of antibacterial masterbatch: The modified dye and the bio-based PTT resin were mixed in a high-speed mixer at a mass ratio of 10:90, pre-dried (temperature 120°C, time 24h), high-temperature melted (temperature 255°C), screw extruded (extrusion temperature 245°C, extrusion pressure 6.5MPa), cooled, and pelletized to obtain the antibacterial masterbatch.

[0081] (3) Preparation of nonwoven fabrics:

[0082] The antibacterial masterbatch and the bio-based PTT resin are weighed in a mass ratio of 4:96, mixed, and spun on a melt spinning machine according to the spinning process of PTT solution-colored fibers to obtain antibacterial colored fibers in the form of short fibers; and then processed according to the polyester nonwoven fabric processing process to obtain a nonwoven fabric;

[0083] Among them, the spinning process of PTT solution-dyed fiber is: pre-baking → high-temperature melting → twin-screw extrusion → annular air cooling → bundling oiling → drawing → cutting → heat setting; the pre-baking temperature is 120°C and the time is 24h; the high-temperature melting temperature is 255°C; the twin-screw extrusion parameters are: extrusion temperature is 250°C, extrusion pressure is 7.0MPa; annular air cooling parameters are: wind speed 0.5m / s, wind temperature 26°C, relative humidity 72%; the parameters of bundling oiling are: special oil for polyester fiber TF-701A, oiling amount 0.5%; the drawing parameters are: drawing multiple 3.5 times, drawing temperature 67°C, drawing speed 1000m / min; cutting is: cutting long fibers into short fibers of about 38mm; the parameters of heat setting are: heat setting temperature 155°C, setting time 30s;

[0084] The processing technology of polyester nonwoven fabric is: opening → feeding → combing → laying → needling → gluing → shaping → rolling; opening: sawtooth roller opening machine, beater speed 520 rpm; feeding: sawtooth roller speed 15 rpm, flap roller speed 18 rpm; combing: fiber web longitudinal and transverse strength ratio 7.5:1; laying: width 3.5m, web machine running 220m / min; needling: needling depth 12mm, needling density 110 needles / cm 2 ; Gluing: polyester hot melt adhesive, polyester hot melt adhesive and pure water are mixed in a mass ratio of 1:1, stirred at high speed to form a slurry, and then coated on the fiber web by a coating device, and hot pressed at 150℃ and 0.1MPa for 5s; shaping: heat setting temperature 145℃, time 35s; rolling: winding speed 230m / min. The polyester hot melt adhesive used for gluing, in terms of mass percentage, its raw materials include: PES copolyester powder 69.5%, ethylene methacrylate glycidyl copolymer 15%, ethylene vinyl acetate copolymer 15%, antioxidant MIANOX616 0.5%, and they are mixed to make hot melt adhesive.

[0085] Results analysis: The modified dye was prepared into a 1.0g / L solution with deionized water, and its average particle size was measured at 25℃ using Nano ZS90 nanoparticle size potential analyzer. Escherichia coli was used as the test strain, and the antibacterial property of the modified dye was evaluated according to GB / T20944.1-2007 "Evaluation of antibacterial properties of textiles Part 1: Agar flat blood diffusion method" (the improvement is: a paper sheet adsorbed with 0.2mL 1.0mg / mL modified dye was flatly pasted on the culture medium after inoculation of bacteria). The antibacterial property of the nonwoven fabric was tested according to GB / T20944.2-2007 "Evaluation of antibacterial properties of textiles Part 2: Absorption method". The strength of the fiber was tested according to GB / T 14337-2008 "Test method for tensile properties of chemical staple fibers".

[0086] See also Figure 1 As shown in Table 1, the modified dye obtained in this example has an inhibition zone of 19.1 mm for Escherichia coli, showing excellent antibacterial performance. The antibacterial rates of the liquid-dyed functional nonwoven fabric obtained in this example against Staphylococcus aureus and Escherichia coli are both 100%, which is much higher than that of the pure nonwoven fabric without the modified dye of the present invention (the antibacterial rates are 35% and 39%, respectively). The average particle size of the modified dye obtained is about 208 nm, which is relatively small, and the strength of the obtained fiber is 3.22 cN·tex -1 , which is not much different from the blank fiber, indicating that the modified dye of the present invention has almost no negative impact on the physical properties of the fiber. It can be seen that the modified dye and nonwoven fabric prepared in this example have excellent antibacterial properties, and the fiber has good mechanical properties (higher fiber strength is conducive to a longer service life of the textile).

[0087] Embodiment 2:

[0088] This example provides a method for preparing a nonwoven fabric and a nonwoven fabric made therefrom, the preparation method comprising:

[0089] (1) Preparation of modified dye: Disperse Red 1 dye was dissolved in anhydrous ethanol to prepare a dye solution with a mass fraction of 2%, and (2-chloroethyl) trimethylammonium chloride was added to the above dye solution at a dry weight ratio of Disperse Red 1 / (2-chloroethyl) trimethylammonium chloride of 9:1 to obtain a pre-reaction solution. Then, the pH value of the pre-reaction solution was adjusted to 10.3 with a 1 mol / L aqueous sodium hydroxide solution, and the pH value was maintained by continuous dripping during the reaction. The reaction was carried out at room temperature for 12 minutes. After the reaction was completed, the pH value was adjusted to 7.0±0.2 with 1 mol / L hydrochloric acid, and finally, the ethanol was removed by reduced pressure evaporation at 50°C to obtain a modified dye.

[0090] (2) Preparation of antibacterial masterbatch: The modified dye and the bio-based PTT resin were mixed in a high-speed mixer at a mass ratio of 15:85, pre-dried (temperature 120°C, time 24h), high-temperature melted (temperature 255°C), screw extruded (extrusion temperature 245°C, extrusion pressure 6.5MPa), cooled, and pelletized to obtain the antibacterial masterbatch.

[0091] (3) Preparation of nonwoven fabrics:

[0092] The antibacterial masterbatch and the bio-based PTT resin are weighed in a mass ratio of 6:94, mixed, and spun on a melt spinning machine according to the spinning process of PTT solution-colored fiber (parameters are the same as in Example 1) to obtain antibacterial colored fibers in the form of short fibers; and then processed according to the polyester non-woven fabric processing process (parameters are the same as in Example 1) to obtain a non-woven fabric.

[0093] Result analysis: After evaluation by the above antibacterial performance test method, the test results are as follows Figure 1 As shown in Table 1, the antibacterial zone of the modified dye obtained in this example against Escherichia coli is 18.6 mm, showing excellent antibacterial performance. The antibacterial rate of the nonwoven fabric processed in this example against Staphylococcus aureus and Escherichia coli is 100%. The average particle size of the modified dye obtained is about 194 nm, which is relatively small, and the strength of the obtained fiber is 3.18 cN·tex -1 , which is not much different from the blank fiber, indicating that the modified dye of the present invention has almost no negative impact on the physical properties of the fiber. It can be seen that the modified dye and nonwoven fabric prepared in this example have excellent antibacterial properties, and the fiber has good mechanical properties.

[0094] Embodiment 3:

[0095] This example provides a method for preparing a nonwoven fabric and a nonwoven fabric made therefrom, the preparation method comprising:

[0096] (1) Preparation of modified dye: Disperse Blue 148 dye was dissolved in anhydrous ethanol to prepare a dye solution with a mass fraction of 2%. (3-chloro-2-hydroxypropyl)trimethylammonium chloride was added to the above dye solution at a dry weight ratio of Disperse Blue 148 / (3-chloro-2-hydroxypropyl)trimethylammonium chloride of 6:1 to obtain a pre-reaction solution. Then, the pH value of the pre-reaction solution was adjusted to 11.5 with a 1 mol / L aqueous sodium hydroxide solution, and the pH value was maintained by continuous dripping during the reaction. The reaction was carried out at room temperature for 60 minutes. After the reaction, the pH value was adjusted to 7.0±0.2 with 1 mol / L hydrochloric acid, and finally, the ethanol was removed by reduced pressure evaporation at 50°C to obtain a modified dye.

[0097] (2) Preparation of antibacterial masterbatch: The modified dye and the bio-based PTT resin were mixed in a high-speed mixer at a mass ratio of 6:94, pre-dried (temperature 120°C, time 24h), high-temperature melted (temperature 255°C), screw extruded (extrusion temperature 245°C, extrusion pressure 6.5MPa), cooled, and pelletized to obtain the antibacterial masterbatch.

[0098] (3) Preparation of nonwoven fabrics:

[0099] The antibacterial masterbatch and the bio-based PTT resin are weighed in a mass ratio of 8:92, mixed, and spun on a melt spinning machine according to the spinning process of PTT solution-colored fibers (parameters are the same as in Example 1) to produce short-fiber antibacterial colored fibers; then processed according to the polyester nonwoven fabric processing process (parameters are the same as in Example 1) to obtain a nonwoven fabric.

[0100] Result analysis: The above antibacterial performance test method was used to evaluate the results. Figure 1 As shown in Table 1, the antibacterial zone of the modified dye obtained in this example against Escherichia coli is 18.8 mm, showing excellent antibacterial performance. The antibacterial rate of the nonwoven fabric processed in this example against Staphylococcus aureus and Escherichia coli is 100%. The average particle size of the modified dye obtained is about 215 nm, which is relatively small, and the strength of the obtained fiber is 3.20 cN·tex -1 , which is not much different from the blank fiber, indicating that the modified dye of the present invention has almost no negative impact on the physical properties of the fiber. It can be seen that the modified dye and nonwoven fabric prepared in this example have excellent antibacterial properties, and the fiber has good mechanical properties.

[0101] Embodiment 4:

[0102] This example provides a method for preparing a nonwoven fabric and a nonwoven fabric made therefrom, the preparation method comprising:

[0103] (1) Preparation of modified dye: Disperse Orange 25 dye was dissolved in anhydrous ethanol to prepare a dye solution with a mass fraction of 2%. (3-chloro-2-hydroxypropyl)trimethylammonium chloride was added to the above dye solution at a dry weight ratio of Disperse Orange 25 / (3-chloro-2-hydroxypropyl)trimethylammonium chloride of 2:1 to obtain a pre-reaction solution. Then, the pH value of the pre-reaction solution was adjusted to 13.5 with a 1 mol / L aqueous sodium hydroxide solution, and the pH value was maintained by continuous dripping during the reaction. The reaction was carried out at room temperature for 90 minutes. After the reaction was completed, the pH value was adjusted to 7.0±0.2 with 1 mol / L hydrochloric acid, and finally, the ethanol was removed by reduced pressure evaporation at 50°C to obtain a modified dye.

[0104] (2) Preparation of antibacterial masterbatch: The modified dye and the bio-based PTT resin were mixed in a high-speed mixer at a mass ratio of 22:78, pre-dried (temperature 120°C, time 24h), high-temperature melted (temperature 255°C), screw extruded (extrusion temperature 245°C, extrusion pressure 6.5MPa), cooled, and pelletized to obtain the antibacterial masterbatch.

[0105] (3) Preparation of nonwoven fabrics:

[0106] The antibacterial masterbatch and the bio-based PTT resin are weighed in a mass ratio of 2:98, mixed, and spun on a melt spinning machine according to the spinning process of PTT solution-colored fiber (parameters are the same as in Example 1) to obtain antibacterial colored fibers in the form of short fibers; and then processed according to the polyester nonwoven fabric processing process (parameters are the same as in Example 1) to obtain a nonwoven fabric.

[0107] Result analysis: After evaluation by the above antibacterial performance test method, the test results are as follows Figure 1 As shown in Table 1, the antibacterial zone of the modified dye obtained in this example against Escherichia coli is 27.5 mm, showing excellent antibacterial performance. The antibacterial rate of the nonwoven fabric processed in this example against Staphylococcus aureus and Escherichia coli is 100%. The average particle size of the modified dye obtained is about 241 nm, which is relatively small, and the strength of the obtained fiber is 3.21 cN·tex -1 , which is not much different from the blank fiber, indicating that the modified dye of the present invention has almost no negative impact on the physical properties of the fiber. It can be seen that the modified dye and nonwoven fabric prepared in this example have excellent antibacterial properties, and the fiber has good mechanical properties.

[0108] Table 1

[0109]

[0110] Comparative Example 1:

[0111] This example provides a method for preparing a nonwoven fabric and the nonwoven fabric prepared therefrom, wherein: (2-chloroethyl)trimethylammonium chloride (structural formula: ) is replaced by 2-dimethylaminoethyl chloride hydrochloride (structural formula: ), and the rest is the same as in Example 1.

[0112] Result analysis: Figure 2 As shown, the diameter of the inhibition zone of the modified dye obtained in this example against Escherichia coli is about 18.8 mm, and it has similar antibacterial activity to the modified dye obtained in Example 1. The nonwoven fabric obtained in this example has an antibacterial rate of 100% against Staphylococcus aureus and Escherichia coli, and the antibacterial performance is similar to that of the product obtained in Example 1, meeting the requirements of the national standard for antibacterial textiles (the antibacterial rates against Staphylococcus aureus and Escherichia coli are both greater than or equal to 85%). However, the average particle size of the modified dye obtained in this example is about 1076 nm, which is much larger than the particle size of the modified dye obtained in Example 1; the strength of the fiber obtained in this example is only 2.85 cN·tex -1 , which is 11.5% lower than that of Example 1, and the strength is poor. Poor fiber strength will seriously affect the service life of nonwoven fabrics. Analysis shows that this is because 2-dimethylaminoethyl chloride hydrochloride can not only react with the tertiary nitrogen structure of the dye to form a quaternary ammonium structure, but the alkyl chloride between 2-dimethylaminoethyl chloride hydrochloride molecules can also undergo electrophilic addition with its own tertiary nitrogen structure to form a cationic polymer, resulting in a very large molecular size of the modified dye. When large particle dyes are mixed into PTT fibers, large structural gaps and stress concentration points are formed in the fiber body, which has a significant adverse effect on the strength of the fiber;

[0113] The reaction formula of cationic polymer is:

[0114]

[0115] Comparative Example 2:

[0116] This example provides a method for preparing a nonwoven fabric and the nonwoven fabric made therefrom, wherein: the pH value of the pre-reaction solution adjusted to 10.3 in Example 2 is changed to the pH value of the pre-reaction solution adjusted to 9.1, that is, the pH value of the pre-reaction solution after adjustment does not meet the range required by the present invention, and the rest is the same as Example 2.

[0117] Result analysis: Figure 2 and Figure 3 As shown, the diameter of the inhibition zone of the modified dye obtained in this example against Escherichia coli is 13.0 mm, which is significantly smaller than the diameter of the inhibition zone of the quaternary ammonium dye obtained in Example 2 (18.6 mm), and the antibacterial activity of the modified dye obtained is relatively low; the average particle size of the modified dye obtained is about 221 nm, and the strength of the obtained fiber is 3.20 cN·tex -1The antibacterial rates of the nonwoven fabric obtained in this example against Staphylococcus aureus and Escherichia coli were 80.3% and 85.5%, respectively, which were significantly inferior to those of the product obtained in Example 2. Analysis showed that this was because the pH value of the reaction system was too low, and the quaternization reaction of the dye was difficult to proceed, resulting in a small amount of final quaternized dye generated, so the antibacterial activity of the modified dye was low, which also resulted in the poor antibacterial performance of the PTT nonwoven fabric containing the dye.

[0118] Comparative Example 3:

[0119] This example provides a method for preparing a nonwoven fabric and the nonwoven fabric prepared therefrom, wherein: (2-chloroethyl)trimethylammonium chloride (structural formula: ) is replaced by chloromethyltrimethylsilane (structural formula: ), and in the preparation process of the antibacterial masterbatch, the mass ratio of the modified dye to the bio-based PTT resin is 20:80, and the rest is the same as in Example 1.

[0120] Result analysis: Figure 4 and Figure 5 As shown, the diameter of the inhibition zone of the modified dye obtained in this example against Escherichia coli is 13.4 mm, which is much smaller than the antibacterial activity of the quaternary ammonium dye obtained in Example 1. The antibacterial rates of the PTT nonwoven fabric obtained in this example against Staphylococcus aureus and Escherichia coli are 83.6% and 88.2%, respectively, and the antibacterial performance does not meet the requirements of the national standard for antibacterial textiles (the antibacterial rates against Staphylococcus aureus and Escherichia coli are both greater than or equal to 85%). The average particle size of the modified dye obtained is about 211 nm, which is relatively small, and the strength of the obtained fiber is 3.13 cN·tex -1 . It is analyzed that: although the alkyl chloride of chloromethyltrimethylsilane can also undergo electrophilic addition reaction with the tertiary nitrogen structure of the dye to form a quaternary ammonium center, the modified dye has only one quaternary ammonium center, and even if the number of quaternary ammonium centers in the system is additionally supplemented to reach the same number of quaternary ammonium centers as in the example, from the practical results, its antibacterial activity is far inferior to that of the dye obtained in the example. It can be seen that the two quaternary ammonium centers in the same dye molecule of the present invention have a synergistic effect.

[0121] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

[0122] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

Claims

1. A modified dye, characterized in that: The preparation method of the modified dye comprises: reacting a disperse dye having a tertiary nitrogen structure with a compound represented by formula (I) under alkaline conditions to generate a modified dye; wherein the pH value of the alkaline conditions is controlled to be greater than or equal to 10; In formula (I), R1 is selected from C 1-3 Alkylene or hydroxy substituted C 1-3 Alkylene, R2, R3, R4 are independently selected from C 1-2 alkyl; Two quaternary ammonium centers separated by R1 are formed in the molecule of the modified dye.

2. The modified dye according to claim 1, characterized in that The disperse dye with tertiary nitrogen structure has the following structure: The modified dye has the following structure: Wherein, R1, R2, R3, and R4 are defined as in claim 1.

3. The modified dye according to claim 1, characterized in that The disperse dye having a tertiary nitrogen structure comprises a combination of one or more selected from the following compounds: and / or, In formula (I), R1 is selected from methylene, ethylene, propylene, hydroxy-substituted methylene, hydroxy-substituted ethylene or hydroxy-substituted propylene, and R2, R3 and R4 are independently selected from methyl.

4. The modified dye according to claim 1, characterized in that The compound represented by formula (I) is a combination of one or more selected from (2-chloroethyl)trimethylammonium chloride, (3-chloropropyl)trimethylammonium chloride, and (3-chloro-2-hydroxypropyl)trimethylammonium chloride; and / or the feed mass ratio of the disperse dye having a tertiary nitrogen structure to the compound represented by formula (I) is 1-10:

1.

5. The modified dye according to claim 1, characterized in that The implementation method of preparing the modified dye includes: dissolving the disperse dye with a tertiary nitrogen structure in anhydrous ethanol to prepare a dye solution, and then adding the compound represented by formula (I) to the dye solution to obtain a pre-reaction solution; then adjusting the pH value of the pre-reaction solution to greater than or equal to 10 with an alkaline hydroxide aqueous solution, reacting at 20-30°C, and continuously adding the alkaline hydroxide aqueous solution during the reaction to maintain the pH value always greater than or equal to 10.

6. The modified dye according to claim 5, characterized in that The mass concentration of the dye solution is controlled to be 0.5%-5%, further 0.8%-3%; and / or, Controlling the molar concentration of the alkaline hydroxide aqueous solution to be 0.5-3 mol / L; and / or, The alkaline hydroxide in the alkaline hydroxide aqueous solution is sodium hydroxide and / or potassium hydroxide, and the alkaline hydroxide aqueous solution is formed by dispersing the alkaline hydroxide in water; and / or, The reaction time of the reaction is controlled to be greater than or equal to 10 minutes, and further to be 12-90 minutes; and / or, After the reaction was completed, the pH value was adjusted to 7.0±0.2 with hydrochloric acid, and then the ethanol was removed by evaporation under reduced pressure.

7. Use of the modified dye according to any one of claims 1 to 6 in the preparation of antibacterial masterbatch or antibacterial colored fiber.

8. A method for preparing a nonwoven fabric, characterized in that: The preparation method comprises: (1) Preparation of modified dyes The disperse dye having a tertiary nitrogen structure is reacted with the compound represented by formula (I) under alkaline conditions to generate a modified dye; wherein the pH value of the alkaline conditions is controlled to be greater than or equal to 10; In formula (I), R1 is selected from C 1-3 Alkylene or hydroxy substituted C 1-3 Alkylene, R2, R3, R4 are independently selected from C 1-2 alkyl; The modified dye has two quaternary ammonium centers separated by R1 in the molecule; (2) Preparation of antibacterial masterbatch The modified dye and the first polyester resin are mixed and melt-extruded to prepare an antibacterial masterbatch; (3) Preparation of antibacterial colored fibers in short fiber form The antibacterial masterbatch is mixed with a second polyester resin, and subjected to a spinning process to prepare an antibacterial colored fiber in a staple form; (4) Preparation of nonwoven fabric The antibacterial colored fiber is used to prepare nonwoven fabric through a nonwoven process.

9. The method for preparing a nonwoven fabric according to claim 8, characterized in that: The first polyester resin and the second polyester resin are bio-based polyester resins, respectively. Furthermore, the first polyester resin and the second polyester resin are independently bio-based poly(trimethylene terephthalate) and / or bio-based poly(butylene succinate); and / or, in step (2), in terms of mass percentage, the modified dye accounts for 5%-25% of the antibacterial masterbatch, and the first polyester resin accounts for 75%-95%; and / or, in step (3), in terms of mass percentage, the antibacterial masterbatch accounts for 1%-10% of the antibacterial colored fiber, and the second polyester resin accounts for 90%-99%; and / or, In step (3), the spinning process includes the following steps performed in sequence: pre-baking, melting, extrusion, cooling, bundling and oiling, drawing, cutting and heat setting; in, The pre-baking temperature is 100-130°C and the time is 10-30h; The melting temperature is 240-270°C; The extrusion is screw extrusion, and the parameters are: the main screw extrusion temperature is 240-255°C, and the extrusion pressure is 6.5-7.2MPa; The cooling is annular air cooling, and the parameters are: wind speed 0.4-0.6m / s, wind temperature 25-28°C, and relative humidity controlled at 65%-85%; The parameters of the bundle oiling are: the oiling amount is 0.3%-0.8% based on the fiber mass percentage; The drawing parameters are: drawing multiple 3-4 times, drawing temperature 65-70°C, and drawing speed 800-1200m / min; The cutting is to cut the long fibers into short fibers of 35-40 mm; The heat setting parameters are: heat setting temperature 150-160° C., time 20-40 s.

10. The method for preparing a nonwoven fabric according to claim 8, characterized in that: In step (4), the nonwoven process comprises the following steps performed in sequence: Opening: Sawtooth roller opener, beater speed 400-700 rpm; Feeding: Sawtooth roller speed 5-25 rpm, flap roller speed 5-30 rpm; Carding: The longitudinal and transverse strength ratio of the fiber web is 5-10:1; Laying net: width 2.5-4.5m, net-forming machine running 150-250m / min; Acupuncture: Acupuncture depth 8-16mm, acupuncture density 70-150 needles / cm 2 ; Gluing: using polyester hot melt adhesive, the polyester hot melt adhesive is mixed with pure water at a mass ratio of 1:0.9-1.1, stirred at high speed into slurry, and then coated on the fiber web by a coating device, and hot pressed at 145-155°C and 0.05-0.15MPa, and further, the hot pressing time is 3-8s; Calculated by mass percentage, the raw materials of the polyester hot melt adhesive include: 67%-72% of PES copolyester powder, 13%-16% of ethylene methacrylate glycidyl copolymer, 13%-16% of ethylene vinyl acetate copolymer, and 0.1%-1% of antioxidant; Setting: Heat setting temperature 140-155℃, time 30-60s; Rolling: Winding speed 150-250m / min.

Images