A high temperature steaming-room temperature stacking-physical scale removal wool anti-felting finishing method based on wide temperature range protease

Abstract

The present application relates to a kind of high temperature steaming-room temperature stacking-physical scale removal wool shrink-proof finishing method based on wide temperature range protease, belong to wool fabric dyeing and finishing field.The present application is impregnated with reducing agent-protease composite working solution to fabric, and working solution includes reducing agent, wide temperature range protease, penetrant and strong strength protective agent and other components;After impregnation, high temperature steaming process is carried out, the disulfide bond in wool scale layer and lipid structure are destroyed, and the hydrolysis efficiency of protease to scale layer is improved;After repeated impregnation working solution, room temperature stacking process is carried out, realize the sufficient hydrolysis, stripping and falling of protease to wool scale under limited condition, finally through physical scale removal process, strengthen shrink-proof effect, so that the shrinkage of the prepared wool fabric reaches machine washable standard (shrinkage <6%), and the strength loss rate is lower (<12%).

Description

Technical Field

[0001] This invention relates to a high-temperature steaming-room-room-room-physical descaling wool anti-felting finishing method based on a wide-temperature-range protease, which belongs to the application technology field of wool textile dyeing and finishing in the wool textile industry. Background Technology

[0002] In the textile industry, wool is a very important protein fiber with excellent drape, warmth retention, acid resistance, and moisture absorption. However, wool fabrics shrink and felt after washing, causing changes in appearance such as fabric size reduction, fuzzing and thickening of the surface, and blurred weave, which seriously affect the performance of the fabric. Therefore, wool needs to be modified to improve the dimensional stability of wool fabrics.

[0003] Currently, there are three main categories of finishing methods used for wool to prevent felting: one is the "subtractive" method, which aims to remove the wool scale layer; another is the "additive" method, which involves coating the wool fabric surface with resin; and the third is a combination of both methods, where the wool scale layer is removed first, followed by resin coating—an "additive-subtractive" method. The most widely used industrial process is the chlorination-Hexeter anti-felting process. While this process effectively improves the dimensional stability of wool fabrics, wool fabrics treated with this process are prone to absorbing chlorine and yellowing, have a poor hand feel, and produce absorbable organic halides (AOX) that are highly hazardous to organisms.

[0004] Enzymatic finishing of wool for anti-felting, as a non-chlorine anti-shrinkage process, has advantages over traditional chlorination processes, including milder operating conditions, higher catalytic efficiency, and environmental friendliness. Fabrics treated with enzymatic anti-shrinkage finishing have a soft hand feel and lustrous color. From a processing perspective, enzymatic finishing of wool for anti-felting can be divided into impregnation, steaming, and cold piling. Compared to impregnation, steaming and cold piling significantly reduce industrial water consumption and wastewater discharge, decrease the circulation and exchange of enzyme solutions and other reagents inside and outside the fabric, and reduce hydrolysis of the fiber interior. However, both steaming and cold piling processes currently have a series of problems that seriously affect their application and promotion. Current steaming and piling processes have stringent temperature requirements. For example, patent CN 102965956 A discloses a composite enzyme padding-steaming anti-felting process, where the steaming temperature is limited to 30–60℃. When the processing temperature exceeds 60℃, the anti-felting effect of wool fabrics is severely affected. Furthermore, during the piling process of wool fabrics, large amounts of urea are often required as fiber swelling agents, which does not conform to the concept of green environmental protection.

[0005] There are many limitations to the enzymatic finishing of wool to prevent felting. From the perspective of protease action sites, due to their small size, protease molecules can penetrate the scale layer and enter the cell membrane complex (CMC) and the cortex inside the fiber. The cortex has a low sulfur content, making it easily attacked by enzymes, causing extensive hydrolysis and breakage of peptide bonds within the fiber, resulting in severe strength damage to the wool fiber. From the perspective of wool's physical structure, the wool scale layer consists of a scale surface, an outer scale, and an inner scale. The scale surface contains 25% lipid structures, and its main component, 18-methyleicosanoic acid (18-MEA), and other fatty acids can cross-link with cysteine ​​residues in the fiber through thioester bonds, forming a dense, hydrophobic barrier on the fiber surface. Furthermore, the outer scale has a high content of disulfide and isomer bonds. These lipid and disulfide bond structures give the fiber strong resistance to water, chemical reagents, and enzyme preparations.

[0006] Therefore, how to construct an enzymatic anti-felting method that can not only confine proteases to the scale layer on the surface of wool to reduce strength loss, but also increase the enzyme's action sites on the wool scale layer to improve the stripping effect on wool scales is a technical problem that urgently needs to be solved. Summary of the Invention

[0007] Technical issues:

[0008] To address the problems of significant strength damage and low scale hydrolysis efficiency in existing enzymatic anti-felting finishing processes, this invention provides a wool anti-felting finishing method. The resulting wool fabrics exhibit a felting rate of less than 6%, a warp strength loss rate of less than 12%, and an alkali solubility of less than 13.1%, meeting the "machine washable" standard.

[0009] Technical solution:

[0010] On the one hand, a method for preventing felting and shrinkage of wool is provided, which includes the following steps:

[0011] (1) First padding with reducing agent-protease composite working solution: The wool fabric is immersed in the reducing agent-protease composite working solution at 60-80℃ to fully wet it, followed by two dips and two paddings, with a liquid carry-over rate of 70-80%; wherein, the reducing agent-protease composite working solution includes a reducing agent, a wide temperature range protease, a penetrant, and a strong protective agent; the wide temperature range protease can have a relative enzyme activity of more than 75% at 25-80℃ and a relative enzyme activity of more than 90% after being kept at this temperature range for 2 hours; the penetrant is a polyoxyethylene nonionic surfactant with a cloud point between 40-80℃;

[0012] (2) High-temperature steaming: The wool fabric obtained in step (1) is placed in a steam environment of 60-90℃ and kept for 20-120 minutes;

[0013] (3) Second impregnation of reducing agent-protease complex working solution: Repeat step (1);

[0014] (4) Room temperature stacking: The wool fabric obtained in step (3) is rolled up and stacked at room temperature for 20-24 hours;

[0015] (5) Physical descaling: The wool fabric obtained in step (4) is acid washed and water washed to remove the enzymatic products and residual auxiliaries on the wool fabric. At the same time, physical descaling is performed by mechanical friction between the guide roller and the wool fabric.

[0016] In some embodiments, the reducing agent-protease composite working solution contains: a reducing agent concentration of 1–10 g / L; a wide-temperature-range protease activity of 10150 U / mL, and an addition amount of 0.6–1.2 mL / L; an addition amount of 0.1–1 mL / L; a strong protective agent concentration of 0.5–2.5 g / L; and a pH of 8–9.

[0017] In some embodiments, the strong protective agent is an anionic polymer with a molecular weight of 3 million to 6 million. For example, the strong protective agent includes at least one of polyacrylic acid, polymethacrylic acid, polyvinyl sulfonic acid, polystyrene sulfonic acid, or anionic polyacrylamide with a molecular weight of 3 million to 6 million.

[0018] In some embodiments, the penetrant includes at least one of alkylphenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether, fatty acid methyl ester polyoxyethylene ether, or fatty acid polyoxyethylene ether.

[0019] In some embodiments, steps (1) and (3) are carried out in a flat-width impregnation unit with a running speed range of 50 to 60 m / min; step (2) is carried out in a steaming unit with a running speed range of 10 to 20 m / min; step (4) is carried out in a rotary stacking unit with a rotation speed range of 20 to 40 rpm; and step (5) is carried out in a hexagonal roller loose flat washing machine with a running speed range of 50 to 60 m / min.

[0020] In some embodiments, step (5) specifically includes three washing processes, the washing solutions used in the three washing processes being pickling solution, wool washing solution a, and wool washing solution b in sequence, the time for each washing process being 10 to 15 minutes, and the temperature of the washing solution being 30 to 35°C; at the same time, the mechanical friction between the guide roller and the wool fabric is used to perform physical descaling; the physical descaling step is carried out in a hexagonal roller type loose flat washing machine, with a running speed of 55 m / min.

[0021] In some embodiments, the pickling solution contains 0.05% to 0.1% acetic acid and 1% to 3% pancreatic bleach T; the washing solution a contains 0.1% to 0.3 g / L Na2CO3 and 1% to 3% pancreatic bleach T, and the washing solution b contains 1% to 3% pancreatic bleach T; the pH of the pickling solution is 4 to 5, the pH of the washing solution a is 9 to 10, and the pH of the washing solution b is 6 to 7.

[0022] In some embodiments, the wool fabric includes worsted woolen fabric. For example, the wool fabric is a lightweight all-wool tweed or a medium-weight all-wool tweed.

[0023] On the other hand, a felt-resistant wool fabric prepared by the aforementioned method is provided.

[0024] Beneficial effects:

[0025] (1) To address the problems of low hydrolysis efficiency and poor peeling effect of ordinary proteases on scales, this invention first screened a wide-temperature-range protease with high temperature tolerance. This wide-temperature-range protease is a commercial enzyme detergent developed by Novo Company, which has high tolerance to extreme environments. Its main component is serine endopeptide protease. This invention found that the wide-temperature-range protease has high enzyme activity and temperature stability within a wide temperature range of 25-80℃. After incubation in solutions at 25-80℃ for 2 hours, its enzyme activity retention rate is greater than 90%. The enzyme has very poor temperature stability under 90℃ solution conditions. After incubation for 10 minutes, its enzyme activity retention rate is only 8.35%. This invention also found that high-temperature steam processing can improve the heat resistance of the wide-temperature-range protease. After incubation in 90℃ high-temperature steam for 1 hour, the enzyme activity retention rate of the wide-temperature-range protease is still 66.85%, which is much higher than the enzyme activity retention rate in 90℃ solution, ensuring that the wide-temperature-range protease can function under 90℃ high-temperature steam conditions. This invention introduces a wide-temperature-range protease that is resistant to high temperatures and reducing agents into the enzymatic anti-felting finishing of wool for the first time. By providing a high-temperature environment through high-temperature steam stacking, the synergistic effect of specific penetrants, reducing agents and strong protective agents is screened, which destroys the lipid structure of wool, increases the accessibility of the wide-temperature-range protease to wool scales and increases the number of action sites, thereby improving the hydrolysis efficiency of the protease on the scales.

[0026] (2) This invention utilizes a reducing agent-protease composite working solution to impregnate the fabric. The working solution contains components such as a reducing agent, a wide-temperature-range protease, a penetrant, and a strong protective agent. After impregnation, a high-temperature steaming process is performed to destroy the disulfide bonds and lipid structures in the wool scale layer, thereby improving the hydrolysis efficiency of the protease on the scale layer. After repeated impregnation with the working solution, a room temperature stacking process is performed to achieve full hydrolysis, peeling, and shedding of the wool scale by the protease under confined conditions. By selecting appropriate penetrants and strong protective agents, this invention weakens the tendency of the protease to enter the cell membrane complex, confining the action of the protease to the wool scale layer and reducing the damage to the internal structure of the wool. Physical peeling of the fabric by the mechanical friction of the hexagonal roller promotes the peeling of scales that have already shown a raised and loose state, strengthens the anti-felt shrinkage effect, and the resulting wool fabric product has excellent dimensional stability (felt shrinkage rate <6%), warp strength loss rate of less than 12%, alkali solubility of less than 13.1%, and strength does not decrease significantly and remains at a high level, which can meet the "machine washable" standard.

[0027] (3) In view of the problem that the protease hydrolysis of wool cell membrane complex and cortex in the traditional impregnation method leads to excessive strength loss, the present invention uses polyoxyethylene nonionic surfactant as a penetrant and anionic polymer as a strong protective agent to reduce the hydrolytic effect of protease on the internal cell membrane complex of the fiber and achieve confined hydrolysis of wool scale layer within a wide temperature range; compared with the large strength loss (≥20%) of wool fabric products obtained by the traditional impregnation method, its value is significantly reduced (<12%).

[0028] (4) This invention improves the defects of high temperature steaming and room temperature stacking, increases the range of steaming temperature selection, enables steaming to be carried out under high temperature conditions of 60-90℃, and reduces the dependence on swelling agent in cold stacking process; at the same time, it retains the advantages of low water consumption and low wastewater discharge, greatly improves the utilization rate of protease, can meet the various requirements of wool fabric flat processing in actual production, and has high economic value.

[0029] (5) Proteases are biological catalysts with high catalytic efficiency and are environmentally friendly. They do not produce AOX during the reaction process, which is more in line with the concept of green environmental protection than the traditional chlorination method. Detailed Implementation

[0030] Flat washing and scouring combined machine: The specific model is M flat washing and scouring combined machine, which consists of TECNOPLUS2000 flat washing machine and WPS continuous scouring machine. The main components include flat-width padding unit, steaming unit and scouring unit. The flat-width padding unit has a running speed of 0 to 80 m / min, the steaming unit has a running speed of 10 to 40 m / min, and the working width is 1200 to 2300 mm. The equipment was purchased from Darmendi (Beijing) Machinery Equipment Co., Ltd.

[0031] Cold pad-batch dyeing machine: The specific model is CPB cold pad-batch dyeing machine. The main components include a flat-width padding unit and a rotary stacking unit. The flat-width padding unit has a running speed of 0-80m / min and a working width of 1200-2300mm. The rotary stacking unit has a rotation speed of 20-40rpm. The equipment was purchased from Lianke Machinery Co., Ltd.

[0032] Hexagonal roller type loose flat washing machine: The specific model is S220-180 loose flat fabric washing machine, which consists of several hexagonal roller type loose flat washing tanks; during operation, the hexagonal rollers exceed the speed by 7% to 9%, which has the function of shaking the washing liquid and rubbing the fabric. The running speed is 50 to 60 m / min. The equipment was purchased from Jiangyin Fuda Dyeing and Finishing United Machinery Co., Ltd.

[0033] Wide temperature range protease: Specific model is Uno 100L is a commercial enzyme detergent. Its main component is serine protease. It can be used in a wide temperature range of 20-80℃ and a wide pH range of 6-11. It has good stability in reducing agents and chelating agents. The measured enzyme activity is 10150U / ml. The enzyme preparation was purchased from Novozymes (China) Investment Co., Ltd.

[0034] Test method:

[0035] 1. Felt shrinkage rate test method

[0036] The dimensional stability of the fabric after washing was determined in accordance with GB 8628-2001 "Preparation, marking and measurement of fabric samples and garments for the test of dimensional change of textiles" and GB 8629-2001 "Domestic washing and drying procedures for textile testing".

[0037] 2. Fracture strength test method

[0038] Referring to GB / T 6529-2008 "Standard Atmospheres for Conditioning and Testing of Textiles" and GB / T 3923.1-2013 "Tension Properties of Textiles - Part 1: Determination of Breaking Strength and Elongation at Break (Strip Method)", the breaking strength and strength loss rate of the treated wool fabric were calculated.

[0039] 3. Alkali solubility test method

[0040] Refer to GB / T 7571-2008 "Determination of Solubility of Wool in Alkali" to calculate the alkali solubility of the treated wool fabric.

[0041] Example 1

[0042] A high-temperature steaming-room-room-room-temperature stacking-physical descaling finishing method for wool based on a wide-temperature-range protease, using pure wool lightweight tweed (197 g / m) as the raw material. 2 The process includes the following steps:

[0043] (1) First padding with reducing agent-protease composite working solution: The wool fabric is immersed in the reducing agent-protease composite working solution at 80℃ and pH 9 for 30s, followed by two dips and two paddings, with a liquid carry-over rate of 75%; The reducing agent-protease composite working solution includes: 3g / L sodium sulfite (used as a reducing agent), a wide temperature range protease with a concentration of 1.2mL / L and an enzyme activity of 10150U / mL, anionic polyacrylamide with a molecular weight of 3 million with a concentration of 1.8g / L (used as a strong protective agent), and 1mL / L octadecanol polyoxyethylene ether (JFC-6) (used as a penetrant); The first padding step with the reducing agent-protease composite working solution is carried out in the flat-width padding unit of the M flat washing and boiling machine, with a running speed of 55m / min;

[0044] (2) High-temperature steaming: The wool fabric obtained in step (1) is placed in a 90℃ steam environment for 20 minutes; the high-temperature steaming step is carried out in the steaming unit of the M-flat washing and boiling machine, and the running speed is 15m / min;

[0045] (3) Second padding reducing agent-protease complex working solution: Repeat step (1), except that the wool fabric is replaced with the wool fabric obtained in step (2). The second padding reducing agent-protease complex working solution step is carried out in the flat padding unit in the CPB cold pad-batch dyeing machine, and the running speed is 55m / min.

[0046] (4) Room temperature stacking: The wool fabric obtained in step (3) is rolled up and stacked, and placed in a room temperature (30°C) environment for 24 hours; the room temperature stacking step is carried out in the rotary stacking unit of the CPB cold pad-batch dyeing machine, with a rotation speed of 20 rpm;

[0047] (5) Physical descaling: The wool fabric obtained in step (4) is subjected to three washing processes. The washing solutions used in the three washing processes are, in order, acid washing solution, washing solution a, and washing solution b. The washing process time for each process is 10 minutes, and the washing solution temperature is 30°C. At the same time, the mechanical friction between the hexagonal guide roller and the fabric is used to perform physical descaling. The acid washing solution contains 0.05% acetic acid and 2% pancreatic bleach T; washing solution a contains 0.2 g / L Na2CO3 and 2% pancreatic bleach T; and washing solution b contains 2% pancreatic bleach T. The physical descaling step is carried out in a hexagonal roller type loose flat washing machine with a running speed of 55 m / min.

[0048] Example 2

[0049] A high-temperature steaming-room-room-room-physical descaling wool anti-felting finishing method based on a wide-temperature-range protease, referring to Example 1, differs in that the impregnation temperature in the first and second impregnation steps of the reducing agent-protease composite working solution is adjusted to 60°C, the steam temperature in the high-temperature steaming step is adjusted to 60°C, and the steaming time is adjusted to 120 min.

[0050] Example 3

[0051] A high-temperature steaming-room-room-room-physical descaling wool anti-felting finishing method based on a wide-temperature-range protease, using 100% wool medium-weight tweed (285 g / m) as the raw material. 2 The process includes the following steps:

[0052] (1) First padding with reducing agent-protease composite working solution: The wool fabric is immersed in the reducing agent-protease composite working solution at 80℃ and pH 8 for 30s, followed by two dips and two paddings, with a liquid carry-over rate of 75%; The reducing agent-protease composite working solution includes: 7.25g / L L-cysteine ​​hydrochloride, a wide temperature range protease with a concentration of 1.2mL / L and an enzyme activity of 10150U / mL, polymethacrylic acid with a molecular weight of 3 million with a concentration of 1.5g / L, and octadecanol polyoxyethylene ether (JFC-6) (used as a penetrant) with a concentration of 1mL / L; The first padding step with the reducing agent-protease composite working solution is carried out in the flat-width padding unit of the M flat washing and boiling machine, with a running speed of 55m / min;

[0053] (2) High-temperature steaming: The wool fabric obtained in step (1) is placed in a 90℃ steam environment for 20 minutes; the high-temperature steaming step is carried out in the steaming unit of the M-flat washing and boiling machine, and the running speed is 15m / min;

[0054] (3) Second padding reducing agent-protease complex working solution: Repeat step (1), except that the wool fabric is replaced with the wool fabric obtained in step (2). The second padding reducing agent-protease complex working solution step is carried out in the flat padding unit in the CPB cold pad-batch dyeing machine, and the running speed is 55m / min.

[0055] (4) Room temperature stacking: The wool fabric obtained in step (3) is rolled up and stacked, and placed in a room temperature (30°C) environment for 24 hours; the room temperature stacking step is carried out in the rotary stacking unit of the CPB cold pad-batch dyeing machine, with a rotation speed of 20 rpm;

[0056] (5) Physical descaling: The wool fabric obtained in step (4) is subjected to three washing processes. The washing solutions used in the three washing processes are, in order, acid washing solution, washing solution a, and washing solution b. The washing process time for each process is 10 minutes, and the washing solution temperature is 30°C. At the same time, the mechanical friction between the hexagonal guide roller and the fabric is used to perform physical descaling. The acid washing solution contains 0.05% acetic acid and 2% pancreatic bleach T; washing solution a contains 0.2 g / L Na2CO3 and 2% pancreatic bleach T; and washing solution b contains 2% pancreatic bleach T. The physical descaling step is carried out in a hexagonal roller type loose flat washing machine with a running speed of 55 m / min.

[0057] Comparative Example 1

[0058] The difference between Comparative Example 1 and Example 1 is that the wool fabric was not treated in any way.

[0059] Comparative Example 2

[0060] A method for preventing felting and shrinkage of wool based on a wide-temperature-range protease, referring to Example 1, is described below. The difference is that the impregnation temperature is adjusted to 30°C in the first and second impregnation steps of the reducing agent-protease composite working solution, and the steam temperature is adjusted to 30°C and the steaming time is 120 min in the steaming step.

[0061] Comparative Example 3

[0062] A wool anti-felting finishing method, the difference between Comparative Example 3 and Example 1 is that the pretreatment and enzyme treatment are carried out by immersion method respectively. The specific process includes the following steps:

[0063] (1) Impregnation reducing agent working solution: The wool fabric is impregnated in the reducing agent working solution at 50℃ and pH value of 11.3 for 1 hour to obtain the fabric pretreated with reducing agent; wherein the reducing agent working solution includes: 10g / L sodium sulfite (used as reducing agent) and 1mL / L octadecanol polyoxyethylene ether (JFC-6) (used as penetrant).

[0064] (2) Cold water wash: Wash the wool fabric obtained in step (1) thoroughly with cold water to remove excess reducing agent;

[0065] (3) Impregnation with protease working solution: The wool fabric obtained in step (2) is impregnated in protease working solution at 80°C and pH 9 for 30 min; the protease working solution includes a wide temperature range protease with a concentration of 1.2 mL / L and an enzyme activity of 10150 U / mL, an anionic polyacrylamide with a molecular weight of 3 million with a concentration of 1.8 g / L (used as a strong protective agent), and octadecanol polyoxyethylene ether (JFC-6) with a concentration of 1 mL / L (used as a penetrant).

[0066] (4) Physical descaling: The wool fabric obtained in step (3) is subjected to three washing processes. The washing solutions used in the three washing processes are, in order, acid washing solution, washing solution a, and washing solution b. The washing process time for each process is 10 minutes, and the washing solution temperature is 30°C. At the same time, the mechanical friction between the hexagonal guide roller and the fabric is used to perform physical descaling. The acid washing solution contains 0.05% acetic acid and 2% pancreatic bleach T; washing solution a contains 0.2 g / L Na2CO3 and 2% pancreatic bleach T; and washing solution b contains 2% pancreatic bleach T. The physical descaling step is carried out in a hexagonal roller type loose flat washing machine with a running speed of 55 m / min.

[0067] Comparative Example 4

[0068] A wool anti-felting finishing method, the difference between Comparative Example 4 and Comparative Example 3 is that the temperature of the impregnation protease working solution is 90℃.

[0069] Comparative Example 5

[0070] A wool anti-felting finishing method, the difference between Comparative Example 5 and Example 1 is that the steps of (3) second impregnation with reducing agent-protease complex working solution and (4) room temperature stacking are omitted, and only steps (1), (2) and (5) are performed.

[0071] Comparative Example 6

[0072] A wool anti-felting finishing method, the difference between Comparative Example 6 and Example 1 is that the steps of (1) first impregnation with reducing agent-protease composite working solution and (2) high temperature steaming are omitted, and only steps (3), (4) and (5) are performed.

[0073] Comparative Example 7

[0074] A wool anti-felting finishing method, the difference between Comparative Example 7 and Example 1 is that (1) the reducing agent-protease complex working solution used in the first padding and (3) the second padding reducing agent-protease complex working solution does not contain any reducing agent.

[0075] Comparative Example 8

[0076] A wool anti-felting finishing method, the difference between Comparative Example 8 and Example 1 is that (1) the reducing agent-protease complex working solution used in the first padding and (3) the second padding reducing agent-protease complex working solution does not contain any strong protective agent.

[0077] Comparative Example 9

[0078] A wool anti-felting finishing method, the difference between Comparative Example 9 and Example 1 is that (1) the penetrant in the reducing agent-protease composite working solution used in the first padding reducing agent-protease composite working solution and (3) the second padding reducing agent-protease composite working solution is replaced with sodium dodecylbenzenesulfonate, with a concentration of 1g / L.

[0079] Comparative Example 10

[0080] A wool anti-felting finishing method, the difference between Comparative Example 10 and Comparative Example 3 is that the latter uses an impregnation method for a reducing agent-enzyme mixed treatment, the specific process is as follows:

[0081] (1) The fabric was immersed in the reducing agent-protease composite working solution at 80°C for 20 minutes. The composition of the working solution was the same as that in Example 1.

[0082] (2) Cold water wash: Wash the wool fabric obtained in step (1) thoroughly with cold water to remove excess reducing agent;

[0083] (3) Physical descaling: The wool fabric obtained in step (2) is subjected to three washing processes. The washing solutions used in the three washing processes are, in order, acid washing solution, washing solution a, and washing solution b. The washing process time for each process is 10 minutes, and the washing solution temperature is 30°C. At the same time, the mechanical friction between the hexagonal guide roller and the fabric is used to perform physical descaling. The acid washing solution contains 0.05% acetic acid and 2% pancreatic bleach T; washing solution a contains 0.2 g / L Na2CO3 and 2% pancreatic bleach T; and washing solution b contains 2% pancreatic bleach T. The physical descaling step is carried out in a hexagonal roller type loose flat washing machine with a running speed of 55 m / min.

[0084] The wool fabrics obtained in Examples 1-3 and Comparative Examples 1-10 were subjected to tests for felting shrinkage, breaking strength loss, and alkali solubility. The results are shown in Table 1.

[0085] Table 1 Performance Test Results

[0086]

[0087]

[0088] As shown in Table 1:

[0089] a. The felting shrinkage rate of the wool fabric samples (Examples 1, 2, and 3) prepared by the method of the present invention was all below 6%, the warp strength loss rate was all below 12%, and the alkali solubility was below 13.1%. This proves that the wool fabric treated by the "high-temperature steaming based on a wide-temperature-range protease-room-room-physical descaling" process can achieve a felting shrinkage rate of less than 6% while maintaining a high strength without significant decrease, thus meeting the "machine washable" standard. Compared with the untreated wool fabric sample (Comparative Example 1), the felting shrinkage rate was significantly reduced, demonstrating a substantial improvement in dimensional stability. At the same time, the strength loss of the wool fabric was low, and the alkali solubility did not change significantly.

[0090] b. Samples treated with the traditional impregnation method (Comparative Examples 3, 4, and 10) showed higher felting shrinkage rates (>6%), higher strength loss rates (>15%), or both, indicating poor overall wool shrinkage resistance. This may be because during the impregnation process, the fabric is in constant contact with a large amount of working solution. The reducing agents or enzymes in the working solution can circulate and exchange within the fabric, causing more severe damage to the fabric's internal CMC (composite microstructure) and thus more easily resulting in serious strength damage. For example, the warp strength loss rates of Comparative Examples 3 and 10 were 20.20% and 25.00%, respectively. Furthermore, the alkali solubility of Comparative Examples 3 and 10 was lower than that of the untreated samples, which is mainly due to the severe structural damage to the wool fabric during the impregnation process. Partial dissolution of the wool fibers occurred during treatment, thus reducing the amount of soluble wool in the alkali solubility test.

[0091] c. Although the felting shrinkage rate of the samples that did not undergo the complete "high-temperature steaming-room-temperature stacking" treatment (Comparative Example 5 and Comparative Example 6) decreased compared to the untreated sample (Comparative Example 1), it was still higher than 10%. This proves that the samples treated only by the high-temperature steaming process (Comparative Example 5) or the room-temperature stacking process (Comparative Example 6) cannot meet the "machine washable" standard. The reason may be that the high-temperature steaming process can destroy some lipids and disulfide bonds, improve the accessibility of proteases to the fabric, and achieve preliminary hydrolysis of wool scales; the room-temperature stacking process can enable proteases to fully bind to the sites on the scales, achieving full hydrolysis of wool scales under confined conditions. Therefore, in this invention, both the high-temperature steaming and room-temperature stacking processes are indispensable.

[0092] d. Samples that were not treated with a composite working solution containing all components (Comparative Example 7 and Comparative Example 8) showed high felting shrinkage (>6%) or high strength loss (>15%), and neither could meet the "machine washable" standard. The working solution of Comparative Example 7 did not contain a reducing agent, so it could not effectively reduce the disulfide bonds on the wool surface. The wool scale layer still maintained a dense structure, and the enzyme reagent could not act on the scale layer, resulting in a high felting shrinkage (10.54%). The working solution of Comparative Example 8 did not contain a strength protectant, so it could not limit the action of the protease to the scale layer, which damaged the wool CMC and internal cortex structure, resulting in a high strength loss (16.38%). The sample treated with an anionic surfactant (sodium dodecylbenzenesulfonate) (Comparative Example 9) showed lower strength loss compared to the nonionic surfactant (octyldecyl alcohol polyoxyethylene ether JFC-6) as a penetrant, but the felting shrinkage rate was 7.32%, which failed to meet the standard. The main reason may be that the wide temperature range protease used in this invention has lower stability in anionic surfactants than in nonionic surfactants, and anionic surfactants have a certain inhibitory effect on its enzyme activity.

[0093] e. This invention has found that, based on the impregnation process, the wide-temperature-range protease used in this invention exhibits high temperature stability at 80°C, but extremely poor temperature stability at 90°C. The felting rate under the 80°C treatment condition (Comparative Example 3) is lower than that under 90°C (Comparative Example 4). This invention has also found that, based on the high-temperature steaming-room-room-temperature stacking-physical scaling method, the felting rate under the 90°C treatment condition (Example 1) is lower than that under 60°C (Example 2) and 30°C (Comparative Example 2), and the treatment time is shorter. This may be because the high-temperature steaming process can improve the heat resistance and operating temperature of the wide-temperature-range protease, allowing it to function in a 90°C steam environment, further overcoming the temperature limitations of high-temperature steaming. When the steam temperature is too low (e.g., 30°C) (Comparative Example 2), lipids cannot dissolve effectively, and the reducing agent cannot effectively break the disulfide bonds in the scale layer, greatly weakening the protease's degradation effect on the scales. Therefore, the suitable steaming temperature based on the method of this invention is 60–90°C.

[0094] The embodiments provided above are not intended to limit the scope of the invention, nor are the described steps intended to limit the order of execution. Any obvious modifications made to the invention by those skilled in the art based on existing common knowledge also fall within the scope of protection defined by the claims.

Claims

1. A method for preventing felting and shrinkage in wool, characterized in that, Includes the following steps: (1) First padding with reducing agent-protease composite working solution: The wool fabric is immersed in the reducing agent-protease composite working solution at 60-80℃ to fully wet it, followed by two dips and two paddings, with a liquid carry-over rate of 70-80%; wherein, the reducing agent-protease composite working solution includes a reducing agent, a wide temperature range protease, a penetrant, and a strong protective agent; the wide temperature range protease can have a relative enzyme activity of more than 75% at 25-80℃ and a relative enzyme activity of more than 90% after being kept at this temperature range for 2 hours; the penetrant is a polyoxyethylene nonionic surfactant with a cloud point between 40-80℃; (2) High-temperature steaming: The wool fabric obtained in step (1) is placed in a steam environment of 60-90℃ and kept for 20-120 minutes; (3) Second impregnation of reducing agent-protease complex working solution: Repeat step (1); (4) Room temperature stacking: The wool fabric obtained in step (3) is rolled up and stacked at room temperature for 20-24 hours; (5) Physical descaling: The wool fabric obtained in step (4) is acid washed and water washed to remove the enzymatic products and residual auxiliaries on the wool fabric. At the same time, physical descaling is performed by mechanical friction between the guide roller and the wool fabric.

2. The method according to claim 1, characterized in that, In the reducing agent-protease composite working solution: the concentration of the reducing agent is 1-10 g / L; the enzyme activity of the wide-temperature-range protease is 10150 U / mL, and the amount of wide-temperature-range protease added is 0.6-1.2 mL / L; the amount of the penetrant added is 0.1-1 mL / L; the concentration of the strong protective agent is 0.5-2.5 g / L; and the pH of the reducing agent-protease composite working solution is 8-9.

3. The method according to claim 1, characterized in that, The strong protective agent is an anionic polymer with a molecular weight of 3 million to 6 million.

4. The method according to claim 3, characterized in that, The strong protective agent includes at least one of polyacrylic acid, polymethacrylic acid, polyvinyl sulfonic acid, polystyrene sulfonic acid, or anionic polyacrylamide with a molecular weight of 3 million to 6 million.

5. The method according to claim 1, characterized in that, The penetrant includes at least one of alkylphenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether, fatty acid methyl ester polyoxyethylene ether, or fatty acid polyoxyethylene ether.

6. The method according to claim 1, characterized in that, Steps (1) and (3) are carried out in the flat-width impregnation unit, with a running speed range of 50 to 60 m / min; Step (2) is carried out in the steaming unit, with a running speed range of 10 to 20 m / min; Step (4) is carried out in the rotary stacking unit, with a rotation speed range of 20 to 40 rpm; Step (5) is carried out in the hexagonal roller loose flat washing machine, with a running speed range of 50 to 60 m / min.

7. The method according to claim 1, characterized in that, Step (5) specifically includes three washing processes. The washing solutions used in the three washing processes are, in order, acid washing solution, wool washing solution a, and wool washing solution b. The time for each washing process is 10 to 15 minutes, and the temperature of the washing solution is 30 to 35°C. At the same time, the mechanical friction between the guide roller and the wool fabric is used to perform physical descaling. The physical descaling step is carried out in a hexagonal roller loose flat washing machine with a running speed of 55 m / min.

8. The method according to claim 7, characterized in that, The pickling solution contains 0.05%–0.1% acetic acid and 1%–3% pancreatic bleach T; the washing solution a contains 0.1–0.3 g / L Na2CO3 and 1%–3% pancreatic bleach T, and the washing solution b contains 1%–3% pancreatic bleach T; the pH of the pickling solution is 4–5, the pH of the washing solution a is 9–10, and the pH of the washing solution b is 6–7.

9. The method according to claim 1, characterized in that, Wool fabrics include worsted wool fabrics.

10. The anti-felting wool fabric obtained by any one of claims 1 to 9.

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