A mildew-proof cotton yarn and a manufacturing process thereof

Abstract

The application relates to a mildew-proof cotton yarn and a manufacturing process thereof; the mildew-proof cotton yarn is treated by a surface treatment agent which comprises isonitrosamine, 4,6-dihydroxy-2-cyanamino pyrimidine, glacial acetic acid, carboxymethyl chitosan, isopropyl alcohol and water and the like. The isonitrosamine, 4,6-dihydroxy-2-cyanamino pyrimidine and glacial acetic acid are reacted together to generate a long-carbon-chain guanidine compound, which can destroy bacterial cell membranes and cause the death of bacteria; the cotton yarn is mainly composed of cotton fibers containing cellulose, the cellulose contains a large amount of hydroxyl groups, and the guanidine organic matter generated by the isonitrosamine, 4,6-dihydroxy-2-cyanamino pyrimidine and glacial acetic acid introduces a polar hydroxyl group, thereby the affinity with the cotton yarn can be improved, on one hand, the antibacterial groups are introduced into the cotton fibers of the cotton yarn, on the other hand, the surface treatment agent is attached to the cotton yarn so that the antibacterial agent is left on the surface of the cotton yarn, thereby the antibacterial property of the cotton yarn is improved in multiple aspects, and a good antibacterial effect is achieved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of cotton yarn, in particular to a mildew-proof cotton yarn and a manufacturing process thereof. BACKGROUND

[0002] Cotton yarn is yarn processed from cotton fibers through a spinning process, and is called cotton thread after plying. According to different spinning processes, the cotton yarn can be divided into common combing yarn and combed yarn. The common combing yarn is spun from cotton fibers through a common spinning system, and the combed yarn is spun from cotton fibers through a combed spinning system. The combed yarn is made of high-quality raw materials, and the fibers in the yarn are straight and parallel, have few impurities, good luster, uniform strip, and high strength. The combed yarn is mostly used for weaving high-grade fabrics.

[0003] At present, a cotton yarn processing process is disclosed in Chinese Patent No. CN109518323A, and belongs to the technical field of textiles. The process comprises the steps of blooming, carding, drawing, yarn forming and yarn steaming, and removes impurities in raw materials.

[0004] According to the related technology in the above, the inventors believe that the current cotton yarn is prone to bacterial attachment in a humid environment, leading to the occurrence of mildew of the cotton yarn, reducing the service life of the cotton yarn, and causing a large amount of waste of cotton yarn products. SUMMARY

[0005] In order to solve the problem of easy mildew of cotton yarn and reduce the waste of cotton yarn products, the application provides a mildew-proof cotton yarn and a manufacturing process thereof.

[0006] In the first aspect, the application provides a mildew-proof cotton yarn adopting the following technical scheme:

[0007] A mildew-proof cotton yarn is treated by a surface treatment agent, and the surface treatment agent comprises the following components in parts by weight:

[0008] 25-35 parts of isononylamine;

[0009] 6-9 parts of 4,6-dihydroxy-2-cyanamino pyrimidine;

[0010] 5-8 parts of glacial acetic acid;

[0011] 2-3 parts of carboxymethyl chitosan;

[0012] 4-5 parts of isopropyl alcohol;

[0013] 15-20 parts of water.

[0014] By adopting the technical scheme, the long carbon chain guanidine compound generated by the reaction of isonitrosamine, 4, 6-dihydroxy-2-cyanoguanidine pyrimidine and glacial acetic acid can make the cell surface structure denature, cause the destruction of the bacterial cell membrane, make the macromolecular organic matter flow out of the cell membrane, and thus cause the death of the bacteria; the cotton yarn is mainly composed of cotton fibers, the main component of the cotton fibers is cellulose, the cellulose molecule contains a large number of hydroxyl groups, and the guanidine organic matter generated by isonitrosamine, 4, 6-dihydroxy-2-cyanoguanidine pyrimidine and glacial acetic acid introduces the heterocyclic pyrimidine group with polarity, thereby the affinity with the cotton yarn can be improved, on one hand, the antibacterial group is introduced into the cotton fibers of the cotton yarn, and on the other hand, the surface treatment agent is attached to the cotton yarn to make the antibacterial agent remain on the surface of the cotton yarn, thereby the antibacterial property of the cotton yarn is improved in multiple aspects, and good antibacterial effect is achieved.

[0015] Preferably, the surface treatment agent further comprises 3-5 parts of the cationic compound by weight.

[0016] By adopting the technical scheme, the cationic compound is added to the surface treatment agent, the cationic groups carried by the cationic compound can make the surface treatment agent more easily adsorbed on the cotton fibers of the cotton yarn; meanwhile, the introduced cations can also combine with the anions dissociated from the silicic acid and phosphoric acid lipids contained in the bacterial cell wall, so as to hinder the free activity of the bacteria, thereby hindering the massive reproduction of the bacteria, so that the cotton yarn obtains the antibacterial and mildew-proof performance.

[0017] Preferably, the preparation method of the cationic compound is as follows: 12-16 parts of calcium alginate, 10-12 parts of sodium citrate and 15-20 parts of water are blended, the pH value is adjusted to 7-10, then 5-8 parts of cyclodextrin and 4-5 parts of isopropyl alcohol are added, and water bath heating is performed to 60-65℃; then 8-11 parts of 40% butyltrimethylammonium chloride aqueous solution is slowly added while stirring, the temperature is increased to 70-80℃, and constant temperature stirring is performed for 5-6h.

[0018] By adopting the technical scheme, the calcium alginate is dissolved in the sodium citrate aqueous solution, the cationic compound is obtained by mixing the calcium alginate, the cyclodextrin and the cationic monomer butyltrimethylammonium chloride, the cavity combination of the cyclodextrin is used to form a complex, the product is given an amino cation group, the affinity with the cotton yarn is improved by using the high molecular calcium alginate and the cyclodextrin, so as to improve the combination degree and introduce the antibacterial cation to modify the cotton yarn and improve the antibacterial property of the cotton yarn.

[0019] Preferably, the weight ratio of the calcium alginate, the cyclodextrin and the butyltrimethylammonium chloride aqueous solution is 7:3:5.

[0020] Preferably, the pH value is 8.

[0021] By adopting the technical scheme, under the alkaline condition with pH value of 8, the calcium alginate, cyclodextrin and cationic monomer butyl trimethyl ammonium chloride are reacted to obtain a cationic compound carrying an ammonia cation group.

[0022] In the second aspect, the application provides a manufacturing process of mildew-proof cotton yarn, which adopts the following technical scheme.

[0023] A manufacturing process of mildew-proof cotton yarn comprises the following steps.

[0024] S1. Preparation of a surface treatment agent; isonorsylamine and glacial acetic acid are uniformly mixed, and the temperature is raised to 30-40 DEG C; then a solution of 4, 6-dihydroxy-2-cyanamino pyrimidine and isopropyl alcohol uniformly mixed is added dropwise, and the reaction is carried out under the condition of 65-70 rpm stirring speed and 1.5-2 h of reaction time, to obtain a guanidyl compound; then carboxymethyl chitosan and water are added, and the mixture is stirred for 40-50 min.

[0025] S2. Cotton yarn pretreatment; the cotton yarn is immersed in a 30% NaOH solution and heated to 40-50 DEG C for 1-1.2 h, and then washed to neutral;

[0026] S3. Surface treatment agent treatment of cotton yarn; the pretreated cotton yarn in S2 is immersed in the surface treatment agent prepared in S1, and double immersion and double rolling are carried out, with a rolling rate of 75-80%, and then the cotton yarn is taken out and placed in an oven at 120-130 DEG C for drying for 15-20 min.

[0027] By adopting the technical scheme, the waxes, pectin and other impurities contained in the cotton fibers of the cotton yarn are removed by using a 30% NaOH solution, so that the cotton yarn is more easily wetted, the contact wetting effect with the surface treatment agent is improved, and the surface treatment agent can rapidly and uniformly penetrate into the interior of the cotton yarn.

[0028] Preferably, after obtaining the guanidyl compound, 3-5 parts of a cationic compound are further added, and the mixture is stirred for 20-30 min; then carboxymethyl chitosan and water are added, and the mixture is stirred for 40-50 min.

[0029] In summary, the application has the following beneficial technical effects:

[0030] 1. The long carbon chain guanidine compound generated by the reaction of isonitrosamine, 4,6-dihydroxy-2-cyano amino pyrimidine and glacial acetic acid can denature the cell surface structure, cause the destruction of the bacterial cell membrane, make the macromolecular organic matter flow out of the cell membrane, and thus lead to the death of bacteria; the cotton yarn is mainly composed of cotton fibers, and the main component of the cotton fibers is cellulose, which contains a large number of hydroxyl groups; and the guanidine organic matter generated by isonitrosamine, 4,6-dihydroxy-2-cyano amino pyrimidine and glacial acetic acid introduces a heterocyclic pyrimidine group with a polar hydroxyl group, thereby improving the affinity with the cotton yarn, on the one hand introducing an antibacterial group into the cotton fibers of the cotton yarn, and on the other hand making the antibacterial agent remain on the surface of the cotton yarn through the surface treatment agent, so as to improve the antibacterial property of the cotton yarn in multiple ways and achieve good antibacterial effect.

[0031] 2. The cationic compound is added to the surface treatment agent, the cationic groups carried by the cationic compound can make the surface treatment agent more easily adsorbed on the cotton fibers of the cotton yarn; at the same time, the introduced cations can also combine with the anions dissociated from the silicic acid and phosphoric acid lipids contained in the bacterial cell wall, so as to hinder the free activity of bacteria, thereby hindering the massive reproduction of bacteria, so as to make the cotton yarn obtain the antibacterial and mildew-proof performance.

[0032] 3. The sodium citrate aqueous solution dissolves the calcium alginate, the cationic compound is obtained by mixing the calcium alginate, cyclodextrin and the cationic monomer butyl trimethyl ammonium chloride under the alkaline condition with pH of 8, the cavity combination of the cyclodextrin can endow the product with the amino cation group, the high molecular calcium alginate and the cyclodextrin are used to improve the affinity with the cotton yarn, so as to improve the combination degree and introduce the antibacterial cation to modify the cotton yarn and improve the antibacterial property of the cotton yarn. DETAILED DESCRIPTION

[0033] The present application is further described below.

[0034] In the present application, the carboxymethyl chitosan is provided by Shaanxi Saien Biological Technology Co., Ltd., and the goods number is SJJ; the calcium alginate is provided by Guangzhou Century Huaming Biological Technology Co., Ltd.; the cyclodextrin is β-cyclodextrin provided by Anhui Qianshun Biological Technology Co., Ltd., and the brand is Stada, and the goods number is 217.

[0035] The raw materials used in the following embodiments can be obtained from ordinary market sales unless otherwise specified.

[0036] The reaction product of isonitrosamine, 4,6-dihydroxy-2-cyano amino pyrimidine and glacial acetic acid is analyzed by infrared spectrum, and the stretching vibration peak of guanidine-C=N appears at 1647 cm -1 , 1256 cm -1 , 1289 cm -1 , 1377 cm -1has C-N stretching vibration peak; at 1610 cm -1 , 1569 cm -1 , 1461 cm -1 and 1400 cm -1 characteristic absorption peaks of pyrimidine ring; and the product has no characteristic absorption peak of cyano-C≡N at 2210-2280 cm -1 , indicating that cyano-C≡N is opened in the reaction. Embodiment

[0037] Embodiment 1

[0038] The embodiment discloses a mildew-proof cotton yarn and a manufacturing process thereof. The mildew-proof cotton yarn is treated by a surface treatment agent, and the surface treatment agent comprises the following components: isononylamine, 4,6-dihydroxy-2-cyanamino pyrimidine, glacial acetic acid, carboxymethyl chitosan, isopropyl alcohol and water, and the content of each component is shown in Table 1.

[0039] The manufacturing process of the mildew-proof cotton yarn comprises the following steps.

[0040] S1. Preparation of the surface treatment agent; uniformly mix isononylamine and glacial acetic acid, and heat to 30 DEG C; then drop the solution of uniformly mixed 4,6-dihydroxy-2-cyanamino pyrimidine and isopropyl alcohol, and heat and stir at a rotating speed of 65 rpm for 1.5 h to obtain a guanidino compound product; then add carboxymethyl chitosan and water, and continue to stir and mix for 40 min.

[0041] S2. Pretreatment of the cotton yarn; immerse the cotton yarn in a 30% NaOH solution and heat to 40 DEG C for 1 h, and then wash to neutral;

[0042] S3. Treatment of the cotton yarn by the surface treatment agent; immerse the pretreated cotton yarn in the surface treatment agent prepared in S1, and perform double immersion and double rolling with a rolling rate of 75%, and then take out and dry in an oven at 120 DEG C for 15 min.

[0043] Embodiment 2

[0044] The embodiment discloses a mildew-proof cotton yarn and a manufacturing process thereof. The mildew-proof cotton yarn is treated by a surface treatment agent, and the surface treatment agent comprises the following components: isononylamine, 4,6-dihydroxy-2-cyanamino pyrimidine, glacial acetic acid, carboxymethyl chitosan, isopropyl alcohol and water, and the content of each component is shown in Table 1.

[0045] The manufacturing process of the mildew-proof cotton yarn comprises the following steps.

[0046] S1. Preparation of surface treatment agent; mix isononylamine and glacial acetic acid uniformly, and heat to 40℃; then add a solution of 4,6-dihydroxy-2-cyanoaminopyrimidine and isopropyl alcohol mixed uniformly, and keep warm and stir at 70 rpm for 2h to obtain guanidino compound product; then add carboxymethyl chitosan and water, and continue to stir and mix for 50 min;

[0047] S2. Pretreatment of cotton yarn; immerse the cotton yarn in 30% NaOH solution and heat to 50℃ for 1.2h, and then wash to neutral;

[0048] S3. Treatment of cotton yarn with surface treatment agent; immerse the pretreated cotton yarn in the surface treatment agent prepared in S1, dip twice and roll twice, with a roll-up rate of 80%, and then take out and dry in an oven at 130℃ for 20 min.

[0049] Example 3

[0050] The present example discloses a mildew-proof cotton yarn and a manufacturing process thereof; a mildew-proof cotton yarn, which is treated with a surface treatment agent, the surface treatment agent comprising the following components: isononylamine, 4,6-dihydroxy-2-cyanoaminopyrimidine, glacial acetic acid, carboxymethyl chitosan, isopropyl alcohol and water, the content of each component being shown in Table 1.

[0051] A manufacturing process of a mildew-proof cotton yarn, comprising the following steps:

[0052] S1. Preparation of surface treatment agent; mix isononylamine and glacial acetic acid uniformly, and heat to 35℃; then add a solution of 4,6-dihydroxy-2-cyanoaminopyrimidine and isopropyl alcohol mixed uniformly, and keep warm and stir at 68 rpm for 1.8h to obtain guanidino compound product; then add carboxymethyl chitosan and water, and continue to stir and mix for 45 min;

[0053] S2. Pretreatment of cotton yarn; immerse the cotton yarn in 30% NaOH solution and heat to 45℃ for 1.1h, and then wash to neutral;

[0054] S3. Treatment of cotton yarn with surface treatment agent; immerse the pretreated cotton yarn in the surface treatment agent prepared in S1, dip twice and roll twice, with a roll-up rate of 78%, and then take out and dry in an oven at 125℃ for 18 min.

[0055] Example 4

[0056] The present example discloses a mildew-proof cotton yarn and a manufacturing process thereof; a mildew-proof cotton yarn, which is treated with a surface treatment agent, the surface treatment agent comprising the following components: isononylamine, 4,6-dihydroxy-2-cyanoaminopyrimidine, glacial acetic acid, carboxymethyl chitosan, isopropyl alcohol, water and a cationic compound, the content of each component being shown in Table 1.

[0057] The preparation method of the cationic compound is as follows: 12 parts of calcium alginate, 10 parts of sodium citrate and 15 parts of water are blended, the pH value is adjusted to 7, then 5 parts of cyclodextrin and 4 parts of isopropyl alcohol are added, and water bath heating is performed to 60℃; then 8 parts of 40% butyl trimethyl ammonium chloride aqueous solution is slowly added while stirring, the temperature is increased to 70℃, and constant temperature stirring is performed for 5h.

[0058] The difference from example 1 is that the manufacturing process of the mildew-proof cotton yarn, and the preparation of the S1 surface treatment agent further includes the following steps:

[0059] The isononylamine and glacial acetic acid are uniformly mixed, and the temperature is increased to 30℃; then the solution of uniformly mixed 4,6-dihydroxy-2-cyanoguanidine pyrimidine and isopropyl alcohol is added dropwise, and the reaction is stirred at 65rpm for 1.5h, to obtain the guanidino compound product;

[0060] The cationic compound is continuously added, and stirring is performed for 20min; then the carboxymethyl chitosan and water are added, and stirring and mixing are continuously performed for 40min.

[0061] Example 5

[0062] The embodiment discloses a mildew-proof cotton yarn and a manufacturing process thereof; the mildew-proof cotton yarn is treated by a surface treatment agent, and the surface treatment agent includes the following components: isononylamine, 4,6-dihydroxy-2-cyanoguanidine pyrimidine, glacial acetic acid, carboxymethyl chitosan, isopropyl alcohol, water and a cationic compound, and the content of each component is shown in Table 1.

[0063] The preparation method of the cationic compound is as follows: 16 parts of calcium alginate, 12 parts of sodium citrate and 20 parts of water are blended, the pH value is adjusted to 10, then 8 parts of cyclodextrin and 5 parts of isopropyl alcohol are added, and water bath heating is performed to 65℃; then 11 parts of 40% butyl trimethyl ammonium chloride aqueous solution is slowly added while stirring, the temperature is increased to 80℃, and constant temperature stirring is performed for 6h.

[0064] The difference from example 2 is that the manufacturing process of the mildew-proof cotton yarn, and the preparation of the S1 surface treatment agent further includes the following steps:

[0065] The isononylamine and glacial acetic acid are uniformly mixed, and the temperature is increased to 40℃; then the solution of uniformly mixed 4,6-dihydroxy-2-cyanoguanidine pyrimidine and isopropyl alcohol is added dropwise, and the reaction is stirred at 70rpm for 2h, to obtain the guanidino compound product;

[0066] The cationic compound is continuously added, and stirring is performed for 30min; then the carboxymethyl chitosan and water are added, and stirring and mixing are continuously performed for 50min.

[0067] Example 6

[0068] The embodiment discloses a mildew-proof cotton yarn and a manufacturing process thereof. The mildew-proof cotton yarn is treated by a surface treatment agent, and the surface treatment agent comprises the following components: isonorsylamine, 4,6-dihydroxy-2-cyanamino pyrimidine, glacial acetic acid, carboxymethyl chitosan, isopropyl alcohol, water and a cationic compound, and the content of each component is shown in Table 1.

[0069] The preparation method of the cationic compound is as follows: 14 parts of calcium alginate, 11 parts of sodium citrate and 18 parts of water are blended, the pH value is adjusted to 9, then 7 parts of cyclodextrin and 5 parts of isopropyl alcohol are added, and water bath heating is performed until the temperature reaches 63 DEG C; then 9 parts of 40% butyl trimethyl ammonium chloride aqueous solution is slowly added while stirring, the temperature is increased to 75 DEG C, and constant temperature stirring is performed for 5.5 hours.

[0070] The difference from the embodiment 3 is that the manufacturing process of the mildew-proof cotton yarn, and the preparation of the S1 surface treatment agent further comprises the following steps.

[0071] The isonorsylamine and the glacial acetic acid are uniformly mixed, and the temperature is increased to 35 DEG C; then the solution obtained by uniformly mixing the 4,6-dihydroxy-2-cyanamino pyrimidine and the isopropyl alcohol is added dropwise, and the reaction is performed for 1.8 hours under the condition of constant temperature and stirring at a rotating speed of 68 rpm, so that a guanidyl compound product is obtained;

[0072] The cationic compound is continuously added, and stirring is performed for 25 minutes; then the carboxymethyl chitosan and the water are added, and stirring and mixing are continuously performed for 45 minutes.

[0073] Embodiment 7

[0074] The difference from the embodiment 4 is that the cationic compound is replaced by butyl trimethyl ammonium chloride, and the content of each component is shown in Table 2.

[0075] Embodiment 8

[0076] The difference from the embodiment 4 is that the calcium alginate is replaced by calcium acetate, and the content of each component is shown in Table 2.

[0077] Embodiment 9

[0078] The difference from the embodiment 4 is that the cyclodextrin is replaced by castor oil, and the content of each component is shown in Table 2.

[0079] Embodiment 10

[0080] The difference from the embodiment 4 is that the butyl trimethyl ammonium chloride is replaced by diallyl dimethyl ammonium chloride, and the content of each component is shown in Table 2.

[0081] Embodiment 11

[0082] The difference from Example 4 is that, by weight parts, the ratio of calcium alginate: cyclodextrin: butyltrimethylammonium chloride aqueous solution is 7:3:5; that is, 14 parts of calcium alginate, 6 parts of cyclodextrin, and 10 parts of butyltrimethylammonium chloride aqueous solution.

[0083] Example 12

[0084] The difference from Example 4 is that in the preparation method of the cationic compound, pH=8.

[0085] Comparative Example

[0086] Comparative Example 1

[0087] The difference from Example 1 is that the cotton yarn was not treated with a surface treatment agent.

[0088] Comparative Example 2

[0089] The difference from Example 1 is that the surface treatment agent consists of 25 parts polyhexamethylene biguanide, 4 parts isopropanol and 15 parts water.

[0090] Comparative Example 3

[0091] The difference from Example 1 is that isononylamine is replaced with 4-(1-methylethyl)-1,2-phenylenediamine.

[0092] Comparative Example 4

[0093] The difference from Comparative Example 3 is that 4,6-dihydroxy-2-cyanoaminopyrimidine is replaced with cyanamide.

[0094] Table 1. Component content of Examples 1-6

[0095] Isornelamine Example 2 Example 3 Example 4 Example 5 Example 6 Isornelamine 25 35 30 25 35 30 4,6-dihydroxy-2-cyanoaminopyrimidine 6 9 7 6 9 7 Glacial acetic acid 5 8 6 5 8 6 Carboxymethyl chitosan 2 3 3 2 3 3 Isopropanol 4 5 4 4 5 4 Water 15 20 18 15 20 18 Cationic compound / / / 3 5 4

[0096] Table 2. Component content of Examples 7-10

[0097] Example 7 Example 8 Example 9 Example 10 Isornelamine 25 25 25 25 4,6-dihydroxy-2-cyanoaminopyrimidine 6 6 6 6 Glacial acetic acid 5 5 5 5 Carboxymethyl chitosan 2 2 2 2 Isopropanol 4 4 4 4 Water 15 15 15 15 Cationic compound / butyl trimethyl ammonium chloride 3 3 3 3

[0098] Performance testing

[0099] According to national standards, the main criterion for testing whether textiles have antibacterial effects against common pathogens such as Staphylococcus aureus (ATCC6538) and Escherichia coli (8099) is the antibacterial rate. When the antibacterial rate reaches 26% or higher, the product can be judged to have antibacterial effect. In this application, referring to Part 3 of GB / T 20944.3-2008 Evaluation of Antibacterial Properties of Textiles, the oscillation method was used to measure the antibacterial rate of cotton yarn produced by the manufacturing processes of each embodiment and comparative example. The test results are shown in Table 3 below.

[0100] Table 3. Antibacterial rate test results for each embodiment and comparative example.

[0101] Staphylococcus aureus inhibition rate / % Escherichia coli inhibition rate / % Example 1 91.35 92.73 Example 2 92.88 94.23 Example 3 92.16 93.48 Example 4 96.46 97.25 Example 5 98.03 98.80 Example 6 97.21 97.96 Example 7 92.19 93.54 Example 8 94.23 95.05 Example 9 95.24 96.02 Example 10 96.35 97.16 Example 11 97.27 98.08 Example 12 97.01 97.73 Comparative Example 1 21.55 22.34 Comparative Example 2 84.79 85.57 Comparative Example 3 89.85 91.24 Comparative Example 4 89.14 90.56

[0102] The specific embodiments are merely illustrative of the present application and do not limit the scope of the present application, and those skilled in the art can make modifications to the embodiments without creative contribution after reading the specification, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A mildew-resistant cotton yarn, characterized in that: The cotton yarn is treated with a surface treatment agent, which comprises the following components in parts by weight: 25-35 parts isononylamine; 6-9 parts of 4,6-dihydroxy-2-cyanoaminopyrimidine; 5-8 parts glacial acetic acid; 2-3 parts carboxymethyl chitosan; 4-5 parts isopropanol; 15-20 parts water; Preparation of surface treatment agent: Mix isononylamine and glacial acetic acid evenly and heat to 30-40℃; Add dropwise the solution of 4,6-dihydroxy-2-cyanoaminopyrimidine and isopropanol, keep warm and stir at 65-70 rpm for 1.5-2 h to obtain guanidine compound; then add carboxymethyl chitosan and water, and continue stirring and mixing for 40-50 min.

2. The mildew-resistant cotton yarn according to claim 1, characterized in that: The surface treatment agent also includes 3-5 parts by weight of a cationic compound.

3. The mildew-resistant cotton yarn according to claim 2, characterized in that: The preparation method of the cationic compound is as follows: 12-16 parts of calcium alginate, 10-12 parts of sodium citrate and 15-20 parts of water are mixed and the pH value is adjusted to 7-10. Then, 5-8 parts of cyclodextrin and 4-5 parts of isopropanol are added and heated in a water bath to 60-65°C. Then, while stirring, 8-11 parts of 40% butyltrimethylammonium chloride aqueous solution are slowly added dropwise, the temperature is raised to 70-80°C, and the mixture is stirred at a constant temperature for 5-6 hours.

4. The mildew-resistant cotton yarn according to claim 3, characterized in that: The ratio of calcium alginate, cyclodextrin, and butyltrimethylammonium chloride aqueous solution by weight is 7:3:

5.

5. The mildew-resistant cotton yarn according to claim 3, characterized in that: The pH is 8.

6. The manufacturing process of the mildew-resistant cotton yarn according to claim 1, characterized in that, Includes the following steps: S1. Preparation of surface treatment agent: Isononylamine and glacial acetic acid are mixed evenly and heated to 30-40℃; then a solution of 4,6-dihydroxy-2-cyanoaminopyrimidine and isopropanol is added dropwise, and the mixture is kept at the temperature and stirred at 65-70 rpm for 1.5-2 h to obtain guanidine compound; then carboxymethyl chitosan and water are added, and the mixture is stirred for 40-50 min. S2. Cotton yarn pretreatment: Immerse the cotton yarn in a 30% NaOH solution and heat it to 40-50℃ for 1-1.2 hours, then wash it with water until it is neutral. S3. Surface treatment agent treatment of cotton yarn: Immerse the cotton yarn pretreated by S2 in the surface treatment agent prepared by S1, dip and nibble twice, with a nibble rate of 75-80%, and then take it out and place it in an oven at 120-130℃ to dry for 15-20 minutes.

7. The manufacturing process of anti-mildew cotton yarn according to claim 6, characterized in that: The process also includes the following steps: after obtaining the guanidine compound, add 3-5 parts of the cationic compound and stir for 20-30 minutes; then add carboxymethyl chitosan and water and continue stirring and mixing for 40-50 minutes.