Method for degumming and bleaching polyester fabrics

Abstract

To provide a degumming and decoloring method for a polyester woven fabric, which can effectively remove a surface preparation agent, a gum film, and dye attached to the polyester woven fabric.SOLUTION: This method includes following steps: a step to provide a first polyester woven fabric to which dye and a gum film or a treatment agent are attached; a step to obtain a second polyester woven fabric by peeling off the gum film or the treatment agent in the first polyester woven fabric by compounding a combination of alkaline aqueous solution and catalysis; and a step to obtain a third polyester woven fabric by decoloring the second polyester woven fabric by combining a chemical reduction method and a chemical oxidation method.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for decolorization, and in particular to a method for degumming and decolorizing polyester fabrics. [Background technology]

[0002] Dyed polyester fabrics typically contain dyes and at least one of a surface treatment and a gum film. Examples of gum films include polyurethane (PU) gum, polymethyl methacrylate (PMMA, acrylic) gum, polyurethane (PU) film, thermoplastic polyurethane (TPU) film, and thermoplastic polyether ester elastomer (TPEE) film. Examples of surface treatments include water-repellent agents. For recycled polyester fabrics, the dyes, surface treatments, and gum films attached to the recycled polyester fabric must be removed.

[0003] Currently known methods for decolorizing polyester fabrics include solvent extraction and chemical bleaching. For solvent extraction methods, see, for example, Taiwan Patent Publication No. I481762, which uses solvent vapor to extract dyes from polyester fibers. For chemical bleaching methods, see, for example, U.S. Pat. No. 5,261,925 A1, which decolorizes polyester fabrics using an ozone oxidation reaction, and U.S. Pat. No. 7,981,337 B2, which decolorizes polyester fabrics using a reduction reaction. However, these decolorization methods typically only remove the dye, but are unable to remove surface treatments or gum films. Furthermore, if the surface treatments and / or gum films on dyed polyester fabrics are not removed, subsequent dye removal can be difficult.

[0004] Therefore, developing a method that can effectively remove dyes, surface treatments, and gum films from polyester fabrics has become an important goal in the art. Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention provides a method for degumming and decolorizing polyester fabrics, which can effectively remove surface treatment agents, gum films, and dyes attached to polyester fabrics. [Means for solving the problem]

[0006] The degumming and bleaching method for polyester fabrics of the present invention includes providing a first polyester fabric having a dye and a gum film or surface treatment agent attached thereto, and sequentially performing degumming and bleaching operations. The degumming operation includes the following operations: mixing a catalyst into a first alkaline aqueous solution to prepare a catalyst solution; immersing the first polyester fabric in the catalyst solution to remove the gum film or surface treatment agent and obtain a second polyester fabric having a dye attached thereto; and bleaching operation includes the following operations: providing a reductive bleaching solution and an oxidative bleaching solution; immersing the second polyester fabric in the reductive bleaching solution to perform a reductive bleaching reaction; and immersing the second polyester fabric in the oxidative bleaching solution to perform an oxidative bleaching reaction to obtain a third polyester fabric.

[0007] In one embodiment of the present invention, the gum film is selected from at least one of a PU gum film, a TPU gum film, a TPEE gum film, and an acrylic gum, and the surface treatment agent is selected from at least one of a fluorine-containing water repellent agent and a fluorine-free water repellent agent.

[0008] In one embodiment of the present invention, the alkaline aqueous solution comprises at least one selected from an alkali metal hydroxide solution, an alkaline earth metal hydroxide solution, an alkaline earth metal carbonate solution, and an alkaline earth metal bicarbonate solution.

[0009] In one embodiment of the present invention, the catalyst comprises at least one selected from a quaternary ammonium salt, a quaternary ammonium base, a quaternary phosphonium salt, and a crown ether.

[0010] In one embodiment of the present invention, the quaternary ammonium salt comprises at least one selected from benzyltributylammonium chloride, benzyltriethylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, tricaprylmethylammonium chloride, dodecyltrimethylammonium chloride, and tetradecyltrimethylammonium chloride.

[0011] In one embodiment of the present invention, the quaternary ammonium base comprises at least one selected from phenyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide, benzyltrimethylammonium hydroxide, triethylmethylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide.

[0012] In one embodiment of the present invention, the quaternary phosphonium salt comprises at least one selected from butyltriphenylphosphonium bromide, ethyltriphenylphosphonium acetate, ethyltriphenylphosphonium iodide, ethyltriphenylphosphonium bromide, and benzyltriphenylphosphonium chloride.

[0013] In one embodiment of the present invention, the crown ether comprises at least one selected from 12-crown-4-ether, 15-crown-5-ether, 18-crown-6-ether, dibenzo-18-crown-6-ether, and diaza-18-crown-6-ether.

[0014] In one embodiment of the present invention, the concentration of the catalyst solution is 0.5 g / L to 20 g / L, and the weight ratio of the catalyst solution to the first polyester fabric is 5:1 to 50:1.

[0015] In one embodiment of the present invention, the reaction conditions for removing the gum film or the surface treatment agent are a reaction temperature of 60° C. to 140° C. and a reaction time of 5 to 60 minutes.

[0016] In one embodiment of the present invention, the reducing and bleaching solution comprises a reducing agent and water, and the reducing agent is at least one selected from ammonium dodecylpoly(oxyethylene) sulfate, sodium dithionite, sodium thiosulfate, sodium hydroxymethanesulfinate, and thiourea dioxide.

[0017] In one embodiment of the present invention, the concentration of the reducing and bleaching solution is 0.5 g / L to 15 g / L, and the weight ratio of the reducing and bleaching solution to the second polyester fabric is 5:1 to 50:1.

[0018] In one embodiment of the present invention, the conditions for the reductive decolorization reaction are a reaction temperature of 90° C. to 140° C. and a reaction time of 5 to 60 minutes.

[0019] In one embodiment of the present invention, the oxidative bleaching solution comprises an oxidizing agent and water, and the oxidizing agent is at least one selected from hydrogen peroxide, sodium nitrate, sodium nitrite, chlorite, hypochlorite, ammonium persulfate, and sodium persulfate.

[0020] In one embodiment of the present invention, the concentration of the oxidative bleaching solution is 0.5 g / L to 15 g / L, and the weight ratio of the oxidative bleaching solution to the second polyester fabric is 5:1 to 50:1.

[0021] In one embodiment of the present invention, the oxidative decolorization reaction conditions are a reaction temperature of 60° C. to 120° C. and a reaction time of 5 to 60 minutes.

[0022] In one embodiment of the present invention, the bleaching process is carried out in the following order: first, a reductive bleaching reaction is carried out on the second polyester fabric, and then an oxidative bleaching reaction is carried out on the second polyester fabric that has undergone the reductive bleaching reaction.

[0023] In one embodiment of the present invention, the bleaching process is carried out in the following order: first, an oxidative bleaching reaction is carried out on the second polyester fabric, and then a reductive bleaching reaction is carried out on the second polyester fabric that has undergone the oxidative bleaching reaction.

[0024] In one embodiment of the present invention, the degumming and bleaching method further comprises drying the third polyester fabric at a drying temperature of 120°C for a drying time of 2 to 4 hours. [Effects of the Invention]

[0025] As described above, the degumming and bleaching method for polyester fabrics of the present invention uses a combination of an alkaline aqueous solution and a catalyst to remove various types of surface treatment agents or gum films from the surface of the polyester fabric, and then bleaches the polyester fabric using a combination of chemical reduction and chemical oxidation. In this way, the surface treatment agents or gum films and dyes on the polyester fabric material can be effectively removed. Furthermore, compared to solvent extraction methods using organic solvents, the present invention is significantly more environmentally friendly because it performs degumming and bleaching on polyester fabrics using aqueous solutions (i.e., aqueous catalyst solution, reductive bleaching solution, and oxidative bleaching solution). [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a flow chart of the method for degumming and bleaching polyester fabric of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] Hereinafter, embodiments of the present invention will be described in detail, but these embodiments are merely examples and do not limit the present invention.

[0028] Here, ranges expressed as "one value to another value" are a summary method for avoiding the need to list every single value in the range in the specification. Thus, the description of a particular numerical range includes any value within that range and smaller numerical ranges defined by any value within that range, and is the same as if that any value and smaller numerical range were explicitly stated in the specification.

[0029] It should be understood that terms such as "first," "second," and "third" may be used herein to describe various elements or signals, but these elements or signals should not be limited by these terms. These terms are primarily used to distinguish one element from another element or one signal from another. Also, the term "or" used herein should include any one or combination of the associated listed items, depending on the actual situation.

[0030] 1 is a flowchart of the method for degumming and bleaching polyester fabrics of the present invention. Referring to FIG. 1, step S100 is carried out to provide a first polyester fabric having a dye and a gum film or surface treatment agent attached thereto. Specifically, polyester fabric generally refers to an article woven from polyester fiber, such as clothing, bags, bedsheets, etc. Polyester fibers are man-made fibers and may include polyethylene terephthalate (PET) fibers, polybutylene terephthalate (PBT) fibers, polytrimethylene terephthalate (PTT) fibers, poly(1,4-cyclohexanedimethylene terephthalate) (PCT) fibers, and poly(ethylene naphthalene-2,6-dicarboxylate) (PEN) fibers, etc. (However, the present invention is not limited thereto.) The type of polyester fiber is not particularly limited in the present invention.

[0031] In this embodiment, the dye may be, for example, a disperse dye, although the present invention is not limited thereto. In some embodiments, the gum film may be, for example, a fluorine-containing water repellent (e.g., perfluorooctanoic acid and its salts, perfluorooctanesulfonyl compounds, alkylphenol polyoxyethylene ethers, perfluoroethanesulfonyl compounds, or sulfonates), a fluorine-free water repellent (e.g., organosilicon water repellents and long-chain hydrocarbon water repellents, such as 3M PM-3705, PM-3888, and Ruco-dry ECO Plus), or a combination thereof, although the present invention is not limited thereto. The gum film may be, for example, a polyurethane gum film, a thermoplastic polyurethane film, a thermoplastic polyetherester elastomer gum film, a polymethyl methacrylate (acrylic) gum, or a combination thereof, although the present invention is not limited thereto.

[0032] Next, step S110 is performed to degumming the first polyester fabric. The degumming process includes the following steps: First, a catalyst is mixed in an alkaline aqueous solution to prepare a catalyst solution. Next, the first polyester fabric is immersed in the catalyst solution to remove the gum film or surface treatment agent, resulting in a second polyester fabric with a dye attached. Here, the second polyester fabric refers to the polyester fabric after the degumming process. That is, the dye is attached to the second polyester fabric, but the gum film and surface treatment agent are not attached, or only a trace amount of gum film and / or surface treatment agent is attached. Specifically, at this stage, the catalyst and alkaline aqueous solution are mixed to remove the surface treatment agent and gum film from the polyester fabric material.

[0033] In the present invention, the catalyst may be, for example, at least one of a quaternary ammonium salt, a quaternary ammonium base, a quaternary phosphonium salt, and a crown ether, but the present invention is not limited thereto. In some embodiments, the quaternary ammonium salt may include at least one selected from benzyltributylammonium chloride, benzyltriethylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, tricaprylmethylammonium chloride, dodecyltrimethylammonium chloride, and tetradecyltrimethylammonium chloride (but the present invention is not limited thereto). In some embodiments, the quaternary ammonium base may include at least one selected from phenyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide, benzyltrimethylammonium hydroxide, triethylmethylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide (but the present invention is not limited thereto). In some embodiments, the quaternary phosphonium salt may include at least one selected from butyltriphenylphosphonium bromide, ethyltriphenylphosphonium acetate, ethyltriphenylphosphonium iodide, ethyltriphenylphosphonium bromide, and benzyltriphenylphosphonium chloride (although the invention is not limited thereto). In some embodiments, the crown ether may include at least one selected from 12-crown-4 ether, 15-crown-5 ether, 18-crown-6 ether, dibenzo-18-crown-6 ether, and diaza-18-crown-6 ether (although the invention is not limited thereto).

[0034] In the present invention, the alkaline aqueous solution may be, for example, an alkali metal hydroxide solution, an alkaline earth metal hydroxide solution, an alkaline earth metal carbonate solution, an alkaline earth metal bicarbonate solution, or a combination thereof, but the present invention is not limited thereto. In some embodiments, the alkali metal hydroxide may include at least one selected from sodium hydroxide (NaOH) and potassium hydroxide (KOH), but the present invention is not limited thereto. In some embodiments, the alkaline earth metal hydroxide may include at least one selected from calcium hydroxide (Ca(OH)), barium hydroxide (Ba(OH)), and magnesium hydroxide (Mg(OH)), but the present invention is not limited thereto. In some embodiments, the alkaline earth metal carbonate may include at least one selected from magnesium carbonate and calcium carbonate, but the present invention is not limited thereto. In some embodiments, the alkaline earth metal bicarbonate may include at least one selected from magnesium bicarbonate and calcium bicarbonate, but the present invention is not limited thereto. Here, the alkaline aqueous solution functions as a solvent, thereby preventing environmental pollution caused by organic solvents.

[0035] In some embodiments, the catalyst concentration in the catalyst solution may be, for example, 0.5 grams / liter (g / L) to 20 g / L, and preferably, for example, 2 g / L to 10 g / L. In some embodiments, the liquor ratio (weight ratio) of the catalyst solution to the first polyester fabric may be, for example, 5:1 to 50:1, and preferably, for example, 8:1 to 20:1. In some embodiments, the reaction conditions for removing the gum film may be, for example, a reaction temperature of 60°C to 140°C and a reaction time of 5 minutes to 60 minutes, and preferably, a reaction temperature of 100°C to 130°C and a reaction time of 20 minutes to 40 minutes. After the degumming operation is completed, the second polyester fabric may be filtered and washed.

[0036] Next, step S120 is carried out to perform the bleaching process. The bleaching process includes at least the following steps: providing a reductive bleaching solution and an oxidative bleaching solution; immersing a second polyester fabric in the reductive bleaching solution to carry out a reductive bleaching reaction; immersing the second polyester fabric that has undergone the reductive bleaching reaction in an oxidative bleaching solution to carry out an oxidative bleaching reaction; removing the dye to obtain a third polyester fabric. Here, the third polyester fabric refers to the polyester fabric after the degumming and dye removal processes. In other words, the third polyester fabric has no dye or gum film attached, or only a trace amount of gum film and / or dye attached. Specifically, at this stage, the dye on the polyester fabric material is removed by the reductive bleaching and oxidative bleaching reactions.

[0037] In the present invention, the reducing and bleaching solution is an aqueous reducing agent solution. In some embodiments, the reducing agent may include at least one selected from ammonium dodecylpoly(oxyethylene) sulfate, sodium dithionite, sodium thiosulfate, sodium hydroxymethanesulfinate, and thiourea dioxide (although the present invention is not limited thereto). Here, the aqueous solution functions as a solvent, thereby preventing environmental pollution caused by organic solvents.

[0038] Specifically, the degummed second polyester fabric is immersed in a reductive bleaching solution. The reducing agent can reduce dye molecules, for example, by reducing the N=N double bond of an azo dye to an NH single bond, thereby removing a portion of the dye (i.e., the dye removed by the reduction reaction). In some embodiments, the concentration of the reducing agent in the reductive bleaching solution can be, for example, 0.5 g / L to 15 g / L, and preferably, for example, 2 g / L to 10 g / L. In some embodiments, the bath ratio (weight ratio) of the reductive bleaching solution to the second polyester fabric can be, for example, 5:1 to 50:1, and preferably, for example, 8:1 to 20:1. In some embodiments, the conditions for the reductive bleaching reaction include a reaction temperature of, for example, 90°C to 140°C and a reaction time of, for example, 5 minutes to 60 minutes. Preferably, the reaction temperature can be, for example, 120°C to 140°C and a reaction time of, for example, 20 minutes to 40 minutes. Within the above temperature and time ranges, the reducing agent has excellent reactivity and can effectively remove dyes from polyester fabrics.

[0039] In the present invention, the oxidative bleaching solution is a combination of an oxidizing agent and water. In some embodiments, the oxidizing agent may include at least one selected from hydrogen peroxide, sodium nitrate, sodium nitrite, sodium chlorite, calcium chlorite, sodium hypochlorite, calcium hypochlorite, ammonium persulfate, and sodium persulfate (although the present invention is not limited thereto). Here, the aqueous solution functions as a solvent, thereby preventing environmental pollution caused by organic solvents.

[0040] Specifically, the second polyester fabric after the reductive bleaching reaction is immersed in an oxidative bleaching solution. During this process, the oxidizing agent oxidizes the dye and breaks the conjugated structure, thereby removing a portion of the dye (i.e., the dye removed by the oxidation reaction). In some embodiments, the concentration of the oxidizing agent in the oxidative bleaching solution may be, for example, 0.5 g / L to 15 g / L, and preferably, for example, 1 g / L to 5 g / L. In some embodiments, the weight ratio of the oxidative bleaching solution to the second polyester fabric may be, for example, 5:1 to 50:1, and preferably, for example, 8:1 to 20:1. In some embodiments, the oxidative bleaching reaction conditions include a reaction temperature of, for example, 60°C to 120°C and a reaction time of, for example, 5 minutes to 60 minutes. Preferably, the reaction temperature may be, for example, 70°C to 100°C, and the reaction time may be, for example, 20 minutes to 40 minutes. When within the above temperature and time ranges, the oxidizing agent has excellent reactivity and can remove dyes from polyester fabrics.

[0041] In the bleaching process, the second polyester fabric may be subjected to a reductive bleaching reaction first, followed by an oxidative bleaching reaction. In another embodiment, the second polyester fabric may be subjected to an oxidative bleaching reaction first, followed by a reductive bleaching reaction. The present invention does not limit the order of the bleaching reactions. It should be noted that in some cases, the bleaching effect of first performing the reductive bleaching reaction is superior to that of first performing the oxidative bleaching reaction.

[0042] Next, step S130 is carried out to dry the third polyester fabric. In some embodiments, the drying conditions may be, for example, a drying temperature of 120°C and a drying time of, for example, 2 to 4 hours, but the present invention is not limited thereto. At this point, degumming and bleaching of the polyester fabric of the present invention are substantially complete.

[0043] The actual effects of the method for degumming and bleaching polyester fabrics of the present invention will be described in detail below with reference to the following embodiments, which, however, are not intended to limit the scope of the present invention.

[0044] Embodiment <Examples 1-12> Examples 1-12 involve the following steps for degumming and bleaching polyester fabrics with gum films or surface treatments (see Table 1) and dyes of different types of materials. Each step is briefly described below.

[0045] (1) Degumming

[0046] A catalyst (see Table 1) is mixed with an aqueous sodium hydroxide solution to prepare a catalyst solution with a concentration of 0.5 g / L to 20 g / L. Next, 10 grams of polyester fabric is added to carry out the degumming reaction. The bath ratio of catalyst solution to polyester fabric is 5:1 to 50:1, the reaction temperature is 60°C to 140°C, and the reaction time is 5 to 60 minutes. The degummed polyester fabric is then subjected to a filtration and drainage process.

[0047] (2) Bleaching

[0048] Sodium dithionite is mixed with water to prepare a reduction bleaching solution with a concentration of 0.5 g / L to 15 g / L. Next, the degummed polyester fabric is added to carry out the reduction bleaching reaction. The reaction temperature is 90°C to 140°C, and the reaction time is 5 to 60 minutes. After that, the polyester fabric that has undergone the degumming and reduction bleaching reaction is subjected to filtration and drainage steps.

[0049] Next, an aqueous solution of ammonium peroxide with a concentration of 0.5 g / L to 15 g / L is added to carry out an oxidative decolorization reaction. The reaction temperature is 60°C to 120°C, and the reaction time is 5 to 60 minutes. After that, the polyester fabric that has undergone the degumming and decolorization process is subjected to a filtration and drainage step.

[0050] (3) Drying

[0051] The polyester fabric that has been degummed and bleached is dried at a drying temperature of 120°C for a drying time of 2 to 4 hours.

[0052] <Comparative Example> Comparative examples include gum films or surface treatments and bleaching steps of dye-attached polyester fabrics.

[0053] (1) Bleaching

[0054] Sodium dithionite is mixed with water to prepare a reduction bleaching solution with a concentration of 0.5 g / L to 15 g / L. Next, 10 grams of polyester fabric is added to carry out the reduction bleaching reaction. The reaction temperature is 90°C to 140°C, and the reaction time is 5 to 60 minutes. After the reduction bleaching reaction, the polyester fabric is filtered and drained.

[0055] Next, an aqueous solution of ammonium peroxide with a concentration of 0.5 g / L to 15 g / L is added to carry out an oxidative decolorization reaction. The reaction temperature is 60°C to 120°C, and the reaction time is 5 to 60 minutes. After that, the decolorized polyester fabric is subjected to a filtration and drainage step.

[0056] (2) Drying

[0057] The polyester fabric that has been bleached is dried at a temperature of 120°C for a time of 2 to 4 hours.

[0058] <Evaluation of bleaching effect> Optical tests were carried out on the polyester fabrics of Examples 1 to 12 and the Comparative Example before treatment and after bleaching treatment.

[0059] A colorimeter is used to measure the L*a*b color system (JIS Z8729 method is used). The higher the L value, the whiter the hue; the higher the a value, the redder the hue; and the higher the b value, the yellower the hue. The measurement results are shown in Table 1.

[0060] [Table 1]

[0061] As can be seen from the results of the Comparative Example and Example 1, Example 1 of the present invention, in which polyester fabric is degummed before bleaching, can achieve better bleaching effects during the bleaching process compared to the Comparative Example in which polyester fabric is directly bleached. As can be seen from the results of Examples 1 to 6, the degumming process of the present invention can be applied to various types of gum films or surface treatment agents, such as PU gum, TPU gum, acrylic gum, TPEE film, fluorine-free water repellents, and fluorine-containing water repellents. Furthermore, as can be seen from the results of Examples 1 and 7 to 12, various catalysts (e.g., tetrabutylammonium bromide, tetrabutylammonium chloride, tetraethylammonium hydroxide, butyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, 18-crown-6 ether, and 12-crown-4 ether) can all be used in the degumming process of the present invention, and all of them help improve the bleaching effect of the subsequent bleaching process.

[0062] As described above, the degumming and bleaching method for polyester fabrics of the present invention uses a combination of an alkaline aqueous solution and a catalyst to remove various types of gum films or treatments from the surface of the polyester fabric, and then bleaches the polyester fabric using a combination of chemical reduction and chemical oxidation. In this way, surface treatments or back film materials, as well as dyes, on the polyester fabric material can be effectively removed. Furthermore, compared to solvent extraction methods using organic solvents, the present invention is significantly more environmentally friendly because it degummes and bleaches polyester fabrics using aqueous solutions (i.e., catalytic alkaline aqueous solution, reduction bleaching solution, and oxidation bleaching solution).

[0063] Although the present invention has been described in detail with reference to the above embodiments, they are not intended to limit the present invention. Those skilled in the art will understand that changes and modifications can be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be defined by the following claims. [Industrial Applicability]

[0064] To provide a method for degumming and decolorizing polyester fabrics, which can effectively remove surface treatment agents or back film materials and dyes on polyester fabric materials. [Explanation of symbols]

[0065] 100, 110, 120, 130 steps

Claims

1. 1. A method for degumming and bleaching polyester fabrics, comprising: providing a first polyester fabric having a dye and a gum film or surface treatment attached thereto; mixing a catalyst into an alkaline aqueous solution to prepare a catalyst solution; immersing the first polyester fabric in the catalyst solution to remove the gum film or the surface treatment agent, thereby obtaining a second polyester fabric having the dye attached thereto; and performing a degumming operation including: providing a reducing bleaching solution and an oxidizing bleaching solution; Immersing the second polyester fabric in the reduction bleaching solution to carry out a reduction bleaching reaction; Immersing the second polyester fabric in the oxidative bleaching solution to carry out an oxidative bleaching reaction; removing the dye to obtain a third polyester fabric; and carrying out a bleaching operation including Including, the gum film is selected from at least one of a polyurethane gum film, a thermoplastic polyurethane gum film, a thermoplastic polyetherester elastomer gum film, and an acrylic gum; the surface treatment agent is selected from at least one of a fluorine-containing water repellent agent and a non-fluorine-containing water repellent agent; A degumming and bleaching method, wherein the catalyst comprises at least one selected from a quaternary ammonium base, a quaternary phosphonium salt, and a crown ether.

2. 2. The degumming and bleaching method of claim 1, wherein the alkaline aqueous solution comprises at least one selected from an alkali metal hydroxide solution, an alkaline earth metal hydroxide solution, an alkaline earth metal carbonate solution, and an alkaline earth metal bicarbonate solution.

3. 2. The degumming and bleaching method of claim 1, wherein the quaternary ammonium base comprises at least one selected from phenyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide, benzyltrimethylammonium hydroxide, triethylmethylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and tetrabutylammonium hydroxide.

4. 2. The degumming and bleaching method of claim 1, wherein the quaternary phosphonium salt comprises at least one selected from butyltriphenylphosphonium bromide, ethyltriphenylphosphonium acetate, ethyltriphenylphosphonium iodide, ethyltriphenylphosphonium bromide, and benzyltriphenylphosphonium chloride.

5. 2. The degumming and bleaching method of claim 1, wherein the crown ether comprises at least one selected from 12-crown-4-ether, 15-crown-5-ether, 18-crown-6-ether, dibenzo-18-crown-6-ether, and diaza-18-crown-6-ether.

6. 2. The degumming and bleaching method according to claim 1, wherein the concentration of the catalyst solution is 0.5 g / L to 20 g / L, and the weight ratio of the catalyst solution to the first polyester fabric is 5:1 to 50:

1.

7. 2. The degumming and bleaching method according to claim 1, wherein the reaction conditions for removing the gum film or the surface treatment agent are a reaction temperature of 60°C to 140°C and a reaction time of 5 minutes to 60 minutes.

8. 2. The degumming and bleaching method of claim 1, wherein the reducing and bleaching solution comprises a reducing agent and water, and the reducing agent comprises at least one selected from ammonium dodecylpoly(oxyethylene) sulfate, sodium dithionite, sodium thiosulfate, sodium hydroxymethanesulfinate, and thiourea dioxide.

9. 2. The degumming and bleaching method according to claim 1, wherein the concentration of the reducing and bleaching solution is 0.5 g / L to 15 g / L, and the weight ratio of the reducing and bleaching solution to the second polyester fabric is 5:1 to 50:

1.

10. 2. The degumming and bleaching method according to claim 1, wherein the conditions for the reductive bleaching reaction are a reaction temperature of 90°C to 140°C and a reaction time of 5 to 60 minutes.

11. 2. The degumming and bleaching method of claim 1, wherein the oxidizing bleaching solution comprises an oxidizing agent and water, and the oxidizing agent is at least one selected from hydrogen peroxide, sodium nitrate, sodium nitrite, sodium chlorite, calcium chlorite, sodium hypochlorite, calcium hypochlorite, ammonium persulfate, and sodium persulfate.

12. 2. The degumming and bleaching method according to claim 1, wherein the concentration of the oxidative bleaching solution is 0.5 g / L to 15 g / L, and the weight ratio of the oxidative bleaching solution to the second polyester fabric is 5:1 to 50:

1.

13. 2. The degumming and bleaching method according to claim 1, wherein the conditions for the oxidative bleaching reaction are a reaction temperature of 60°C to 120°C and a reaction time of 5 minutes to 60 minutes.

14. 2. The degumming and bleaching method according to claim 1, wherein the bleaching steps are carried out in the order of first carrying out the reductive bleaching reaction on the second polyester fabric, and then carrying out the oxidative bleaching reaction on the second polyester fabric that has undergone the reductive bleaching reaction.

15. 2. The method for degumming and bleaching according to claim 1, wherein the bleaching steps are carried out in the following order: first, an oxidative bleaching reaction is carried out on the second polyester fabric, and then a reductive bleaching reaction is carried out on the second polyester fabric that has undergone the oxidative bleaching reaction.

16. 2. The degumming and bleaching method according to claim 1, wherein the third polyester fabric is dried under the conditions of a drying temperature of 120° C. and a drying time of 2 to 4 hours.

Images