Non-woven fabric debleaching method combining enzymatic treatment and ozone treatment

Abstract

The present invention discloses a non-woven fabric debleaching method combining enzymatic treatment and ozone treatment, belonging to the technical field of debleaching. It includes: subjecting the hydroentangled non-woven fabric to enzymatic treatment at a temperature of 25-50°C for a treatment time of 1-3 h; the enzymatic treatment solution includes a first composite bio-enzyme agent and a surfactant, the concentration of the first composite bio-enzyme agent is 4-8 g / L, and the concentration of the surfactant is 1-3 g / L. The first composite bio-enzyme agent includes pectinase, cellulase, and horseradish peroxidase; then, nitrilotriacetic acid and a second composite bio-enzyme agent are added to the enzymatic treatment solution, and the enzymatic treatment is carried out at a temperature of 40-70°C for a treatment time of 0.5-1.5 h; the concentration of the second composite bio-enzyme agent is 1-3 g / L, and the concentration of nitrilotriacetic acid is 6-12 g / L. The second composite bio-enzyme agent includes laccase and xylanase; then, ozone is introduced into the enzymatic treatment solution for ozone debleaching treatment; finally, the product is obtained after washing with water and drying.

Description

Technical Field

[0001] The present invention belongs to the technical field of debleaching, and particularly relates to a non-woven fabric debleaching method combining enzyme treatment and ozone treatment. Background Art

[0002] At present, the technology of ozone bleaching of cotton fabrics has been relatively mature. For example, the patent with the application number CN202110784565.3 discloses a method for debleaching cotton webs with a composite enzyme, and the method includes:

[0003] (1) Enzyme ultrasonic composite cold pad-batch: Treat the cotton web in an enzyme cold pad-batch solution by ultrasonic waves. The conditions for ultrasonic treatment are: the frequency of ultrasonic waves is 40 - 100 KHz, and the time is 30 - 60 minutes; the enzyme cold pad-batch solution includes a composite bio-enzyme agent and a surfactant. The concentration of the composite bio-enzyme agent is 6 - 14 g / L, the concentration of the surfactant is 0.5 - 4.0 g / L, and the composite bio-enzyme agent includes cellulase, pectinase, protease, lipase, laccase, and glucose oxidase;

[0004] (2) Ozone atmosphere treatment: Expose the cotton web treated in step (1) in an ozone atmosphere for 0.5 - 2.0 hours, and the volume concentration of ozone in the ozone atmosphere is 20 - 40%;

[0005] (3) Hydroentangling: Hydroentangle the cotton web treated in step (2).

[0006] Although this method has a good bleaching effect, it still has the following problems:

[0007] (1) During enzyme treatment, ultrasonic treatment is required simultaneously. Ultrasonic treatment may cause the temperature of the enzyme cold pad-batch solution to rise, and temperature control is needed. If not controlled, the temperature of the enzyme cold pad-batch solution will be too high, affecting the activity of the enzyme;

[0008] (2) For ozone atmosphere treatment, high sealing requirements are needed, and both feeding and discharging may overflow; in addition, it is very difficult to achieve a volume concentration of ozone of 20 - 40%. Summary of the Invention

[0009] In order to solve the foregoing problems, the present invention provides a non-woven fabric debleaching method combining enzyme treatment and ozone treatment. Compared with the prior art, adjustments are made in the enzyme treatment, and the ozone treatment can be carried out in a solution, which is easy to achieve. The technical solution is as follows:

[0010] The present invention provides a non-woven fabric debleaching method combining enzyme treatment and ozone treatment, and the method includes the following steps:

[0011] (1) First enzyme treatment: The undesized and unbleached cotton spunlace nonwoven fabric is subjected to enzyme treatment at a temperature of 25 - 50 °C for a treatment time of 1 - 3 h. Among them, the enzyme treatment solution includes a first composite bio - enzyme agent and a surfactant. The concentration of the first composite bio - enzyme agent is 4 - 8 g / L, and the concentration of the surfactant is 1 - 3 g / L. Among them, the first composite bio - enzyme agent is composed of pectinase, cellulase, and horseradish peroxidase in a mass ratio of 1.0 - 3.0:1.5 - 4.0:2.5 - 6.0. Among them, the surfactant is selected from DMA, JFC, or Peregal O, etc.

[0012] (2) Second enzyme treatment: After step (1) is completed, a chelating agent and a second composite bio - enzyme agent are added to the enzyme treatment solution. The enzyme treatment is carried out at a temperature of 40 - 70 °C for a treatment time of 0.5 - 1.5 h. Among them, the concentration of the second composite bio - enzyme agent is 1 - 3 g / L, and the concentration of the chelating agent is 6 - 12 g / L. Among them, the second composite bio - enzyme agent is composed of laccase and xylanase in a mass ratio of 1.0:2.5 - 5.0, and the chelating agent is nitrilotriacetic acid.

[0013] (3) Ozone treatment: After step (2) is completed, ozone is introduced into the enzyme treatment solution for ozone de - sizing treatment. Ozone is continuously introduced at a rate of 0.05 - 0.2 m 3 / h for a treatment time of 20 - 45 min and a treatment temperature of 40 - 50 °C.

[0014] (4) Washing and drying: The nonwoven fabric treated in step (3) is washed and dried to obtain the product.

[0015] The beneficial effects brought by the technical solution provided by the present invention are:

[0016] 1. The pectinase and horseradish peroxidase react synergistically. The enzyme treatment is carried out step by step, and different enzymes cooperate with each other. The removal efficiency of pectin and cottonseed hulls is high, the retention rate of cotton wax is high, the nonwoven fabric has good hygroscopicity, and the hand feeling is smooth.

[0017] Specifically, the selected enzyme types are: pectinase, xylanase, laccase, cellulase, and horseradish peroxidase (HRP). The enzyme treatment is carried out in two steps. First, the nonwoven fabric is treated with pectinase, cellulase, and HRP. Pectinase and cellulase promote the removal of pectin and other impurities. At the same time, Ca hydrolyzed from pectin 2+It can promote the decomposition of lignin by HRP, soften the cottonseed hulls, and form a better synergistic treatment effect. In the second step, NTA, laccase, and xylanase are added. NTA removes the pectin that was not removed in the first step and chelates metal ions, while laccase and xylanase further remove the softened cottonseed hulls. Through the adjustment of the types, ratios, and treatment processes of the enzymes, compared with non-stepwise treatment, its advantage lies in only selecting enzyme combinations with known good composite effects for stepwise treatment, avoiding the problem of poor composite effects of multiple enzymes. At the same time, key treatment is carried out on pectin and cottonseed hulls. After treatment, the retention rate of cotton wax on the non-woven fabric is high, and the moisture absorption performance meets the standard. The surface friction performance is more excellent and smoother and skin-friendly compared with other enzyme treatment methods.

[0018] 2. Three-way synergy of enzymes, chelating agents, and ozone. The chelating agent synergizes with the enzyme treatment to catalyze the ozone bleaching process, making the entire debleaching process more efficient.

[0019] Specifically, since various impurities in cotton fibers adhere to cotton fibers with pectin as the framework, promoting the removal of pectin can effectively remove impurities. Most of the carboxyl groups of the pectin substance on cotton fibers exist in the form of metal salts and methyl esters. The calcium and magnesium ions bound in pectin can effectively combine with the chelating agent to form chelates. As the metal ions in pectin are removed, the binding force between other impurities in the hydrophobic network layer with pectin as the framework decreases and is successively removed during scouring and further removed by washing. After chelating agent treatment, ozone bleaching is used, which can form a metal chelate-catalyzed ozone system. The metal chelate formed by the chelating agent and transition metal ions can conceal the metal ions, reducing the concentration of metal ions in the aqueous solution, greatly reducing the consumption rate of metal ions, enabling the metal ions to have a good continuous catalytic effect, reducing the consumption rate of ozone, and improving the bleaching efficiency.

[0020] 3. Chelating agents improve reaction efficiency. Select amino carboxylic acid metal ion chelating agents and introduce active groups to improve reaction efficiency.

[0021] Select nitrilotriacetic acid (NTA) as the chelating agent. While promoting the debleaching process, it introduces more active groups, making the reaction easier to proceed. NTA is an amino carboxylic acid metal ion chelating agent. Amino carboxylic acid chelating agents have little pollution, good chelating effect on metal ions, and good thermal stability. After treatment with amino carboxylic acid chelating agents, the content of hydroxyl and carboxyl groups on the surface of cotton fibers is higher, which is beneficial to the subsequent debleaching process of all-cotton spunlace non-woven fabrics. Detailed implementation methods

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below.

[0023] Example 1:

[0024] Example 1 provides a method for debleaching non-woven fabrics by enzymatic treatment in cooperation with ozone treatment. The method comprises the following steps:

[0025] (1) First enzymatic treatment: The unbleached all-cotton hydroentangled non-woven fabric is subjected to enzymatic treatment at a temperature of 40 °C for 2 h. The enzymatic treatment solution comprises a first composite bio-enzyme agent and Peregal O. The concentration of the first composite bio-enzyme agent is 6.75 g / L, and the concentration of the surfactant is 3 g / L. Among them, the first composite bio-enzyme agent is composed of pectinase, cellulase and horseradish peroxidase in a mass ratio of 2:3:4.

[0026] (2) Second enzymatic treatment: After step (1) is completed, nitrilotriacetic acid and a second composite bio-enzyme agent are added to the enzymatic treatment solution. The enzymatic treatment is carried out at a temperature of 50 °C for 1 h. Among them, the concentration of the second composite bio-enzyme agent is 2 g / L, and the concentration of nitrilotriacetic acid is 10 g / L. Among them, the second composite bio-enzyme agent is composed of laccase and xylanase in a mass ratio of 1.0:2.5 - 5.0.

[0027] (3) Ozone treatment: After step (2) is completed, ozone is introduced into the enzymatic treatment solution for ozone debleaching treatment. Ozone is continuously introduced at 0.1 m 3 / h for 30 min, and the treatment temperature is 45 °C.

[0028] (4) Washing and drying: The non-woven fabric treated in step (3) is washed and dried to obtain the product.

[0029] After testing: The whiteness of the product is 85.66, the pectin removal rate is 88.81%, the cotton wax removal rate is 28.32%, the friction coefficient is 0.15, and the water absorption rate is 10.52 g.

[0030] Among them, the test methods for whiteness, pectin removal rate, cotton wax removal rate, friction coefficient and water absorption rate in this example are as follows:

[0031] 1 Whiteness: Using a WSD-II d / o whiteness meter, referring to GB / T8425-1987 "Instrumental Evaluation Method for Whiteness of Textiles", the specimen is folded into 2 layers, and measured 4 times at different parts of the fabric, and the average value is taken. Among them, the nominal value of the standard whiteness board is 71.3.

[0032] 2 Pectin removal rate: Using ammonium oxalate extraction-carbazole colorimetry: Weigh 1.5 g of the dry mass of the all-cotton hydroentangled non-woven fabric, cut it into pieces and place it in a 250 mL flask, add 100 mL of 0.5% ammonium oxalate solution, connect the condenser, boil it in a boiling water bath for 1.5 h, filter, and take 2 mL of the filtrate and add it to 12 mL of concentrated H 2 SO 4Cool it in ice water, then boil it in a boiling water bath for 10 min, then cool it with 0℃ cold water, and finally add 1 mL of 0.15% carbazole anhydrous ethanol solution, mix well, let it stand for 30 min, measure the absorbance value with a 721 spectrophotometer at a wavelength of 530 nm, and then calculate the mass fraction of galacturonic acid from the standard curve to obtain the mass fraction of pectin.

[0033] 3 Cotton wax removal rate: Weigh 10 g (accurate to 0.0001 g) of the sample that has been cut into pieces and pre-dried to constant weight in an oven at 105℃. Place the sample in a paper tube made of filter paper, and place the paper tube in a fat extractor. The height of the tube is 1 - 1.5 cm higher than the upper end of the siphon of the extractor, and the height of the sample in the paper tube is 1 - 1.5 cm lower than the top of the siphon. Add 120 mL of carbon tetrachloride to the flask of the fat extractor, place it in a constant temperature water bath, adjust the temperature, and keep the solvent siphon circulate 3 - 4 times per hour. After extraction for 3 h, cool it, and filter the extraction liquid containing the waxy substance in the flask of the extractor into a triangular flask of known weight. Wash the flask, filter paper and funnel of the extractor with the solvent 3 times, and heat and distill it on a water bath. After all the solvent has evaporated, place the triangular flask in an oven, dry it to constant weight at 105℃, and accurately weigh it after cooling in a dryer.

[0034] 4 Coefficient of friction: Use the FTT fabric touch tester developed by SDL ATLAS Company and The Hong Kong Polytechnic University. Take 3 samples for each sample, and the sample size is an "L" - shaped sample of 31 cm×31 cm with a width of 11 cm. Characterize the fabric contact comfort condition through the mechanical test indexes of the fabric under micro - deformation.

[0035] 5 Water absorption: The water absorption test of spunlace all - cotton non - woven materials refers to GB / T24218.6—2010 "Textiles - Test methods for non - woven fabrics - Part 6: Determination of absorbency". Weigh the sample with a size of 100 mm×100 mm, put the sample into water, take it out after 60 s, hang the sample vertically for 120 s and then weigh it again to calculate the water absorption.

[0036] Verification example

[0037] The following verifies this method, and the test process is as follows:

[0038] Test group 1 is the same as Example 1;

[0039] Test group 2: Compared with test group 1, adjust the type of chelating agent to sodium tripolyphosphate, and other processes are the same as Example 1;

[0040] Control group 1: Compared with test group 1, no chelating agent is added, and other processes are the same as Example 1;

[0041] Control group 2, compared with experimental group 1, does not perform enzymatic treatment step by step, but uses a complex enzyme for one-step treatment, and other processes are the same as those in Example 1;

[0042] Control group 3, compared with experimental group 1, uses the complex enzyme combination used in Patent CN202110784565.3, and other processes are the same as those in Example 1;

[0043] Control group 4, compared with experimental group 1, uses ozone atmosphere treatment, and other processes are the same as those in Example 1;

[0044] Control group 5, compared with experimental group 1, adjusts the order of the first enzymatic treatment and the second enzymatic treatment, and other processes are the same as those in Example 1.

[0045] The whiteness of the cotton web before processing is 68, the gram weight of the non-woven fabric product is 40 g / m 2 , and the material is pure cotton. The setting methods of the experimental group and the control groups are shown in Table 1:

[0046] Table 1

[0047]

[0048] Note: In the table, 1 and 2 represent the addition order of the enzyme agents. 1 is added in the first step, and 2 is added in the second step.

[0049] The results are shown in Table 2:

[0050] Table 2

[0051]

[0052] It can be seen from Table 2 that both experimental group 1 and experimental group 2 have good bleaching effects, high pectin removal rates, good hygroscopicity, low friction factors, and good smoothness. In comparison, experimental group 1 has an advantage in whiteness. It can be seen from experimental group 1 and control group 1 that without adding a chelating agent for auxiliary treatment, the bleaching effect of the pure cotton spunlace non-woven fabric is significantly reduced, the pectin removal rate also decreases, and the hygroscopicity is poor. It can be seen from experimental group 1 and control group 2 that without performing step-by-step enzymatic treatment, the pectin removal rate decreases, but the cotton wax removal rate increases. The bleaching effect is not as good as that of step-by-step enzymatic treatment, and the friction factor is relatively high, and the smoothness decreases. It can be seen from experimental group 1 and control group 3 that the complex enzyme combination of control group 3 has a good effect on removing cotton wax, but the increase in the cotton wax removal rate does not significantly improve the hygroscopicity, and it increases the friction factor and decreases the smoothness. It can be seen from experimental group 1 and control group 4 that the bleaching effect of ozone atmosphere treatment is not as good as that of liquid-phase treatment. It can be seen from experimental group 1 and control group 5 that after exchanging the order of enzymatic treatment, the de-bleaching effect is significantly reduced, and the whiteness and hygroscopicity decrease significantly.

[0053] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. Non-woven fabric debleaching method combining enzymatic treatment and ozone treatment, characterized in that, the method comprises the following steps: (1) First enzymatic treatment: subject the spunlace non-woven fabric to enzymatic treatment at a temperature of 25 - 50 °C for 1 - 3 h; the enzymatic treatment solution comprises a first composite bio-enzyme agent and a surfactant, the concentration of the first composite bio-enzyme agent is 4 - 8 g / L, the concentration of the surfactant is 1 - 3 g / L, and the first composite bio-enzyme agent comprises pectinase, cellulase and horseradish peroxidase; (2) Second enzymatic treatment: after step (1) is completed, add a chelating agent and a second composite bio-enzyme agent to the enzymatic treatment solution, and carry out enzymatic treatment at a temperature of 40 - 70 °C for 0.5 - 1.5 h; the concentration of the second composite bio-enzyme agent is 1 - 3 g / L, the concentration of the chelating agent is 6 - 12 g / L, the second composite bio-enzyme agent comprises laccase and xylanase, and the chelating agent is nitrilotriacetic acid; (3) Ozone treatment: after step (2) is completed, introduce ozone into the enzymatic treatment solution for ozone debleaching treatment; (4) Water washing and drying: subject the non-woven fabric treated in step (3) to water washing and drying to obtain the product; In step (1), the mass ratio of pectinase, cellulase and horseradish peroxidase is 1.0 - 3.0:1.5 - 4.0:2.5 - 6.0; In step (2), the mass ratio of laccase and xylanase is 1.0:2.5 - 5.0; In step (3), ozone is continuously introduced at 0.05 - 0.2 m 3 / h for 20 - 45 minutes at a treatment temperature of 40 - 50 °C.

2. The non-woven fabric debleaching method combining enzymatic treatment and ozone treatment according to claim 1, characterized in that, in steps (1) - (3), the bath ratio is 1:25 - 40.

3. The non-woven fabric debleaching method combining enzymatic treatment and ozone treatment according to claim 2, characterized in that, the surfactant is selected from DMA, JFC or Peregal O.

4. The non-woven fabric debleaching method combining enzymatic treatment and ozone treatment according to claim 1, characterized in that, in step (4), after the ozone treatment is completed, drain the enzymatic treatment solution and add clear water for water washing.

5. The non-woven fabric debleaching method combining enzymatic treatment and ozone treatment according to claim 1, characterized in that, the method comprises the following steps: (1) First enzymatic treatment: subject the spunlace non-woven fabric to enzymatic treatment at a temperature of 25 - 50 °C for 1 - 3 h; the enzymatic treatment solution comprises a first composite bio-enzyme agent and a surfactant, the concentration of the first composite bio-enzyme agent is 4 - 8 g / L, the concentration of the surfactant is 1 - 3 g / L, and the first composite bio-enzyme agent is composed of pectinase, cellulase and horseradish peroxidase in a mass ratio of 1.0 - 3.0:1.5 - 4.0:2.5 - 6.0, and the surfactant is selected from DMA, JFC or Peregal O; (2) Second enzyme treatment: After step (1) is completed, a chelating agent and a second composite bio-enzyme agent are added to the enzyme treatment solution. The temperature of the enzyme treatment is 40 - 70 °C, and the treatment time is 0.5 - 1.5 h. The concentration of the second composite bio-enzyme agent is 1 - 3 g / L, the concentration of the chelating agent is 6 - 12 g / L. The second composite bio-enzyme agent is composed of laccase and xylanase in a mass ratio of 1.0:2.5 - 5.0, and the chelating agent is nitrilotriacetic acid; (3) Ozone treatment: After step (2) is completed, ozone is introduced into the enzyme treatment solution for ozone debleaching treatment. The ozone is continuously introduced at a rate of 0.05 - 0.2 m 3 / h, the treatment time is 20 - 45 min, and the treatment temperature is 40 - 50 °C; (4) Washing and drying: The non-woven fabric treated in step (3) is washed and dried to obtain the product.

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