Bio-based water repellent, water repellent fabric, and methods of making and using the same

Abstract

This application relates to the technical field of fabric finishing, and particularly to a bio-based water repellent, a water-repellent fabric, and their preparation methods and applications. By designing a non-isocyanate polyurethane obtained by the reaction of a cyclic carbonate and an amine, which contains no fluorine element and isocyanate group residue, and has one or more hydroxyl groups in the molecular chain to provide adhesion to nylon 66 or polyamide fabrics, and then using dehydroabietylamine to cap it, thereby improving the washability and wrinkle resistance of the bio-based water repellent. On this basis, aminopropyl heptaisobutylcage polyhedral oligomeric silsesquioxane is also used as an optional auxiliary capping agent to further improve the waterproofness of the bio-based water repellent.

Description

Technical Field

[0001] This application relates to the field of fabric finishing technology, and in particular to a bio-based water-repellent agent, a water-repellent fabric, and its preparation method and application. Background Technology

[0002] Water-repellent agents provide excellent and long-lasting waterproofing to fabric surfaces without altering the fabric's feel or breathability. Commonly available water-repellent agents for fabrics include fluorocarbon polymers, silicones, and long-chain hydrocarbon polymers. Fluorinated water-repellent agents exhibit excellent waterproofing due to their good crystallinity and bulk density; however, organofluorine chemicals such as PFOS (perfluorooctane sulfonate) and PFOA (perfluorooctanoic acid) have bioaccumulation, varying degrees of toxicity, persistence, and potential hazards, thus limiting the use of fluorine-containing finishing agents. Based on the principle of avoiding fluorine use, there is increasing research and development into fluorine-free water-repellent finishing agents. Commercially available fluorine-free water-repellent agents are mostly long-chain alkane and silicone polymers. While fluorine-free water-repellent finishing agents are less prone to accumulation in the body and pose less harm to humans, making them relatively safe and environmentally friendly products, their lack of bioaccumulation and potential for harm to humans contribute to their safety. However, these polymers are thermoplastic and have a significantly different chemical structure from fabrics like nylon 66. This results in insufficient adhesion to the fabric surface, particularly in terms of washability, which fails to meet expectations and leads to a decrease in water resistance after multiple washes. If a cross-linking agent is used to cure the polymer, problems with softness and breathability arise.

[0003] The solution to the above problems is to synthesize polyurethane containing one or more isocyanates by combining polyols with isocyanate monomers, and then use it as a fluorine-free water-repellent agent for fabrics such as nylon 66. For example, Chinese patent CN112646118A uses a polyol with two functionalities as the main material to react with isocyanate monomers such as TDI and MDI to prepare a fluorine-free water-repellent agent. Chinese patent CN118344934B uses a bio-based polyol to react with a special isocyanate methyl-(3-isocyanopropyl)dimethylsilane to prepare a fluorine-free water-repellent agent. However, these technical routes still use monomers containing isocyanate groups, and unreacted -NCO residues remain during the reaction process. These residues may be absorbed by the human body through skin contact or small amounts of volatilization, thus directly increasing health risks. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the technical problem this invention aims to solve is to provide a bio-based water-repellent agent that is free of fluorine and isocyanate residues, while also exhibiting high water resistance with no significant decrease in water resistance after washing and folding. The main structure of the bio-based water-repellent agent is a non-isocyanate polyurethane obtained by reacting cyclic carbonates and amines, completely free of free isocyanate residues. Furthermore, the presence of hydroxyl groups in the middle of its molecular chain provides adhesion to fabrics. Finally, bio-based monoamine dehydrorosin amine is used for end-capping to improve the water-repellent agent's wash resistance.

[0005] This invention is achieved through the following technical solution:

[0006] In the first aspect, a bio-based water-repellent agent is a non-isocyanate polyurethane having the structure of formula (I), wherein the end of the non-isocyanate polyurethane is capped by dehydrorosin amine residues.

[0007] (I);

[0008] Where n is a positive integer greater than or equal to 1;

[0009] R1 is selected from ;

[0010] Preferably, R1 is selected from or ;

[0011] R2 is selected from C1-C12 straight-chain hydrocarbon group or C1-C12 branched hydrocarbon group, and R2 contains at least one hydroxyl group; or, R2 contains at least one ether bond;

[0012] Preferably, R2 is selected from or ;

[0013] Further optimization, R2 is selected from... ;

[0014] R3 is selected from C2-C30 straight-chain aliphatic hydrocarbon group, C2-C30 branched aliphatic hydrocarbon group, C2-C30 cyclic aliphatic hydrocarbon group or C6-C30 aromatic hydrocarbon group, or R3 contains at least one ether bond;

[0015] Preferably, R3 is selected from , or

[0016] , where m≥1.

[0017] Secondly, the preparation method of the above-mentioned bio-based water-repellent agent includes: reacting a polyol with dimethyl carbonate to obtain a cyclic carbonate, then performing a ring-opening polymerization reaction with a diamine, and finally using dehydrorosin amine as a capping agent for end-capping.

[0018] The polyol is selected from diglycerol, bis-(trimethylol)propane or pentaerythritol;

[0019] Preferably, the polyol is selected from diglycerides;

[0020] The diamine is selected from aliphatic diamines and aromatic diamines, wherein the amino group is directly connected to a non-aromatic ring;

[0021] Preferably, the aliphatic diamine is selected from one or more combinations of 4,4'-diaminodicyclohexylmethane, polyetheramine, 1,2-ethylenediamine, 1,6-hexanediamine, 1,10-decanediamine, isophoronediamine, and cyclohexanedimethylamine.

[0022] Preferably, the aromatic diamine is selected from one or more combinations of o-phenylenediamine, m-phenylenediamine, and p-phenylenediamine;

[0023] Preferably, an inorganic base is used as a catalyst in the reaction of polyols with dimethyl carbonate;

[0024] Preferably, the molar ratio of the hydroxyl group of the polyol to dimethyl carbonate is 1:(1-2);

[0025] Even more preferably, the molar ratio of the hydroxyl group of the polyol to dimethyl carbonate is 1:(1-1.5);

[0026] Preferably, the inorganic base is potassium carbonate or sodium carbonate;

[0027] Preferably, the reaction between the polyol and dimethyl carbonate is carried out at 70-100°C for 12-48 hours;

[0028] Preferably, the amount of the inorganic base is (0.1-0.5) wt% of the total amount of polyol and dimethyl carbonate.

[0029] Preferably, the reaction temperature for the ring-opening polymerization of cyclic carbonate and diamine is (100-140)℃;

[0030] Preferably, the molar ratio of the cyclic carbonate group to the amino group of the diamine in the cyclic carbonate is (1.1-1.5):1;

[0031] Even more preferably, the molar ratio of the cyclic carbonate group to the amino group of the diamine in the cyclic carbonate is (1.2-1.3):1;

[0032] Preferably, the molar ratio of the cyclic carbonate group to the amino group of the dehydrorosin amine in the cyclic carbonate is (4-8):1;

[0033] Even more preferably, the molar ratio of the cyclic carbonate group to the amino group of the dehydrorosin amine in the cyclic carbonate is (5-6):1;

[0034] Furthermore, aminopropyl heptaisobutyl cage-like polysilsesquioxane may be optionally used as a capping agent for end capping;

[0035] Preferably, the molar ratio of the cyclic carbonate group of the cyclic carbonate to the amino group of the aminopropyl heptaisobutyl cage polysilsesquioxane is (25-40):1.

[0036] Preferably, the bio-based water-repellent agent is formulated into a solution using an alcohol solvent, and its solid content is (10-40)%.

[0037] Preferably, the alcohol solvent includes one or more combinations of methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, and tert-butanol.

[0038] Thirdly, the application of the aforementioned bio-based water-repellent agents in the field of fabric finishing.

[0039] Fourthly, a water-repellent fabric is obtained by impregnating the fabric with the above-mentioned bio-based water-repellent agent, followed by a one-dip-one-roll process and then drying and shaping it.

[0040] The fabric is selected from either nylon or nylon 66.

[0041] Preferably, the drying and shaping conditions are: pre-drying at 100-140℃ for 10 minutes, followed by baking at 130-180℃ for 1-30 minutes.

[0042] Fifthly, the application of the water-repellent fabrics mentioned above in the production of outdoor clothing.

[0043] The beneficial effects of this application's technical solution are as follows: A non-isocyanate polyurethane is designed from the reaction of cyclic carbonates and amines, completely free of fluorine elements and isocyanate group residues. The molecular chain contains one or more hydroxyl groups to provide adhesion to nylon 66 or nylon fabrics. Dehydrorosin amine is then used to end-cap the polyurethane, thereby improving the wash resistance and wrinkle resistance of the bio-based water-repellent agent. Furthermore, aminopropylheptaisobutyl cage-like polysilsesquioxane is used as an optional auxiliary end-capping agent, further enhancing the water resistance of the bio-based water-repellent agent. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of this application and to more completely understand this application and its beneficial effects, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1The 1H NMR spectrum of the water-repellent agent prepared in Example 3 1 H-NMR (CDCl3).

[0046] Figure 2 Carbon NMR spectrum of the water-repellent agent prepared in Example 3 13 C-NMR (CDCl3).

[0047] Figure 3 The 1H NMR spectrum of the water-repellent agent prepared in Example 7 1 H-NMR (CDCl3).

[0048] Figure 4 Carbon NMR spectrum of the water-repellent agent prepared in Example 7 13 C-NMR (CDCl3). Detailed Implementation

[0049] The present application will be further described in detail below with reference to the embodiments and examples. It should be understood that these embodiments and examples are for illustrative purposes only and are not intended to limit the scope of the present application. The purpose of providing these embodiments and examples is to enable a more thorough and comprehensive understanding of the disclosure of the present application. It should also be understood that the present application can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various modifications or alterations without departing from the spirit of the present application, and the equivalent forms obtained also fall within the protection scope of the present application. Furthermore, numerous specific details are set forth in the following description to provide a fuller understanding of the present application. It should be understood that the present application can be implemented without one or more of these details.

[0050] Unless otherwise specified, the experimental conditions used in the examples are generally in accordance with conventional conditions in the art or the conditions recommended by the reagent company. Unless otherwise specified, the materials and reagents used in the examples can be purchased commercially.

[0051] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0052] the term

[0053] Unless otherwise stated or in case of contradiction, the terms or phrases used herein shall have the following meanings:

[0054] The terms "and / or," "or / and," and "and / or" as used herein include any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. It should be noted that when at least three items are connected by at least two conjunctions selected from "and / or," "or / and," and "and / or," it should be understood that in this application, the technical solution undoubtedly includes technical solutions connected by "logical AND," and also undoubtedly includes technical solutions connected by "logical OR." For example, "A and / or B" includes three parallel solutions: A, B, and A+B. For example, the technical solution of "A, and / or, B, and / or, C, and / or, D" includes any one of A, B, C, and D (that is, a technical solution that is connected by "logical OR"), as well as any and all combinations of A, B, C, and D, that is, combinations of any two or three of A, B, C, and D, and also combinations of all four of A, B, C, and D (that is, a technical solution that is connected by "logical AND").

[0055] In this application, the terms "multiple", "various", "multiple times", "multi-dimensional", etc., unless otherwise specified, refer to a quantity greater than or equal to 2. For example, "one or more" means one or more than or equal to two.

[0056] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0057] In this application, the technical features described in an open-ended manner include both closed-ended technical solutions composed of the listed features and open-ended technical solutions containing the listed features.

[0058] In this application, numerical intervals (i.e., numerical ranges) are involved. Unless otherwise specified, the selected numerical distributions within the aforementioned numerical intervals are considered continuous and include the two endpoints (i.e., the minimum and maximum values) of the numerical range, as well as every value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints. In this document, this is equivalent to directly listing every integer. For example, if t is an integer selected from 1 to 10, it means that t is any integer selected from the group of integers consisting of 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Furthermore, when multiple ranges are provided to describe features or characteristics, these ranges can be merged. In other words, unless otherwise specified, the ranges disclosed herein should be understood to include any and all subranges to which they are included.

[0059] Unless otherwise specified, the temperature parameters in this application are permitted to be either constant-temperature treatment or variations within a certain temperature range. It should be understood that the constant-temperature treatment allows temperature fluctuations within the precision range of the instrument control, such as ±5℃, ±4℃, ±3℃, ±2℃, or ±1℃.

[0060] In this application, % (w / w) and wt% both represent weight percentage, % (v / v) refers to volume percentage, and % (w / v) refers to mass-volume percentage.

[0061] All references to documents mentioned in this application are incorporated herein by reference as if each document were individually incorporated herein by reference. Unless they conflict with the inventive purpose and / or technical solution of this application, all cited documents are incorporated herein by reference in their entirety and for all purposes. When citing documents in this application, the definitions of relevant technical features, terms, nouns, phrases, etc., are also incorporated herein by reference. When citing documents in this application, examples and preferred embodiments of the cited technical features may also be incorporated herein by reference, but only to the extent that they enable the implementation of this application. It should be understood that when the cited content conflicts with the description in this application, this application shall prevail or modifications shall be made adaptably to the description in this application.

[0062] Example 1

[0063] Preparation of diglycerol-based bicyclic carbonate: 166.17 g (1 mol) of diglycerol, 450 g (5 mol) of dimethyl carbonate and 1.5 g of potassium carbonate catalyst were added to a three-necked flask. The mixture was heated to 82 °C and refluxed for 24 hours. After the reaction was completed, the mixture was cooled to room temperature. Excess dimethyl carbonate and methanol byproduct were removed by distillation at room temperature. The product remaining in the flask was recrystallized from the product with ethyl acetate to obtain diglycerol-based bicyclic carbonate.

[0064] The structure of the above-mentioned diglyceryl dicyclic carbonate was confirmed as follows:

[0065] 1H NMR spectrum 1 H-NMR (CDCl3, 400 MHz): δ3.78(4H, m), 4.43-4.55(4H, m), 4.61(2H, m).

[0066] Carbon NMR 13 C-NMR (CDCl3, 400 MHz): δ66.24 (2C), 71.70 (2C), 74.29 (2C), 154.84 (2C).

[0067] Example 2

[0068] Preparation of pentaerythritol bicyclic carbonate: 136.12 g (1 mol) of pentaerythritol, 450 g (5 mol) of dimethyl carbonate and 1.5 g of potassium carbonate catalyst were added to a three-necked flask. The mixture was heated to 90 °C and refluxed at this temperature for 24 hours. A water separator was used to separate the methanol obtained from the reaction. After the reaction was completed, the mixture was cooled to room temperature and distilled at room temperature to remove unreacted dimethyl carbonate and methanol. The product remaining in the flask was recrystallized from the product with ethyl acetate to obtain pentaerythritol bicyclic carbonate.

[0069] The structure of the above pentaerythritol bicyclic carbonate was confirmed as follows:

[0070] 1H NMR spectrum 1 H-NMR (CDCl3, 400 MHz): δ4.56 (8H, d, J = 14.37 Hz).

[0071] Carbon NMR 13 C-NMR (CDCl3, 400 MHz): δ32.2(1C), 63.3(4C), 148.9(2C).

[0072] Example 3

[0073] 65.45 g (0.3 mol) of the diglycerol-based bicyclic carbonate prepared in Example 1, 16.34 g (0.12 mol) of m-phenylenediamine, and 27.60 g (0.12 mol) of polyetheramine D230 were weighed and added to a three-necked flask. After melting, mechanical stirring was started, nitrogen gas was introduced, and the flask temperature was raised to 110 °C. The reaction was carried out at this temperature for 5 hours. After the viscosity of the reaction mixture increased significantly, the amine value was measured to be below 3 (mg KOH / g). Then, 34.26 g (0.12 mol) of the end-capping agent dehydrorosin amine was added and reacted with the above prepolymer at 120 °C for 2 hours. After cooling to 50 °C, the product was dissolved in a 3:1 ethanol / n-butanol mixed solution to prepare a polyurethane alcohol solution with a solid content of (20±2)%.

[0074] 1H NMR spectrum of the product of Example 3 1 H-NMR (CDCl3, 400 MHz) and carbon NMR spectrum 13 C-NMR (CDCl3, 400 MHz) characterization is listed in Figure 1 and Figure 2 middle.

[0075] Example 4

[0076] The diamine in the reactants was replaced with 16.83 g (0.08 mol) of 4,4'-diaminodicyclohexylmethane, 10.89 g (0.08 mol) of p-phenylenediamine and 18.4 g (0.08 mol) of polyetheramine D230, while the remaining raw materials and operating procedures were the same as in Example 3.

[0077] Example 5

[0078] The capping agent was replaced with 17.5g (0.02mol) of aminopropyl heptaisobutyl cage polysilsesquioxane and 28.55g (0.1mol) of dehydrorosin amine. The remaining raw materials and operating steps were the same as in Example 3.

[0079] Example 6

[0080] The capping agent was replaced with 17.5g (0.02mol) of aminopropyl heptaisobutyl cage polysilsesquioxane and 28.55g (0.1mol) of dehydrorosin amine. The remaining raw materials and operating steps were the same as in Example 4.

[0081] Example 7

[0082] The bicyclic carbonate in the reactants was replaced with 56.44 g (0.3 mol) of pentaerythritol bicyclic carbonate prepared in Example 2, and the remaining raw materials and operating steps were the same as in Example 3.

[0083] 1H NMR spectrum of the product of Example 7 1H-NMR (CDCl3, 400 MHz) and carbon NMR spectrum 13 C-NMR (CDCl3, 400 MHz) characterization is listed in Figure 3 and Figure 4 middle.

[0084] Example 8

[0085] The bicyclic carbonate in the reactants was replaced with 56.44 g (0.3 mol) of pentaerythritol bicyclic carbonate prepared in Example 2, and the remaining raw materials and operating steps were the same as in Example 4.

[0086] Example 9

[0087] The capping agent was replaced with 17.5 g (0.02 mol) of aminopropyl heptaisobutyl cage polysilsesquioxane and 28.55 g (0.1 mol) of dehydrorosin amine. The remaining raw materials and operating steps were the same as in Example 7.

[0088] Example 10

[0089] The capping agent was replaced with 17.5 g (0.02 mol) of aminopropyl heptaisobutyl cage polysilsesquioxane and 28.55 g (0.1 mol) of dehydrorosin amine. The remaining raw materials and operating steps were the same as in Example 8.

[0090] Comparative Example 1

[0091] No capping agent was used; the remaining raw materials and operating steps were the same as in Example 3.

[0092] Comparative Example 2

[0093] No capping agent was used; the remaining raw materials and operating steps were the same as in Example 7.

[0094] A nylon fabric sample (180mm × 180mm) was immersed in a water-repellent finishing agent, and then dried and set using a one-dip-one-pinch process to obtain a water-repellent nylon fabric. The drying and setting conditions were: pre-drying at 120℃ for 10 minutes and baking at 140℃ for 5 minutes.

[0095] A sample of nylon 66 fabric (180mm × 180mm) was immersed in a water-repellent finishing agent, and then dried and set using a one-dip-one-pinch process to obtain a water-repellent nylon fabric. The drying and setting conditions were: pre-drying at 120℃ for 10 minutes and baking at 140℃ for 5 minutes.

[0096] Performance testing section

[0097] The water-repellent performance was evaluated according to the water-dip method of GB / T4745-2012 standard, in which the water was selected from deionized water and the water temperature was controlled at (27±2)℃. The water-repellent performance was tested for the initial water-repellent performance, the water-repellent performance after 30 washes, and the water-repellent performance after 1000 folding tests.

[0098] The performance test results are recorded in Table 1.

[0099] Analysis of the data in Table 1 shows that the bio-based water-repellent agents prepared in Examples 3-6 have the best overall performance. Using dehydrorosin amine as a capping agent can improve water washability. On this basis, adding aminopropyl heptaisobutyl cage-like polysilsesquioxane can further improve water repellency. Regarding the selection of bicyclic carbonate monomers, Examples 3-6 use diglycerol-based bicyclic carbonate, which contains an ether bond in the middle, which is beneficial to improve the flexibility of the water-repellent agent. It can still maintain a high water repellency level after 1000 folding tests. Examples 7-10 use pentaerythritol bicyclic carbonate, which reduces flexibility, and the water repellency level also decreases accordingly after 1000 folding tests.

[0100] Comparative Examples 1 and 2 did not use dehydrorosin amine as a capping agent, and their water washability decreased significantly. This is because dehydrorosin amine contains a rigid rosin ring hydrophobic group. The benzene ring therein can combine with the aryl group in the water repellent agent or the aryl group in nylon 66 through π-π interaction to form a dense structure, thereby reducing the interaction between the molecular chain and water molecules and reducing the adsorption and penetration rate of water.

[0101] Table 1

[0102]

[0103] Finally, it should be noted that the above-described embodiments are merely illustrative of several implementation methods of this application, intended to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the patent application. It should be pointed out that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Furthermore, it should be understood that after reading the above teachings of this application, those skilled in the art can make various alterations or modifications to this application, and the equivalent forms obtained also fall within the scope of protection of this application. It should also be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. A bio-based water repellent agent, characterized in that, The bio-based water-repellent agent is a non-isocyanate polyurethane with the structure of formula (I), wherein the end of the non-isocyanate polyurethane is capped with dehydrorosin amine residues. (I)； Where n is a positive integer greater than or equal to 1; R1is selected from ; R2is selected from or ; R3is selected from , or where m >

1.

2. A process for the preparation of a bio-based water repellent as claimed in claim 1, characterized in that, The polyol was first reacted with dimethyl carbonate to obtain cyclic carbonate, which was then subjected to ring-opening polymerization with diamine. Finally, dehydrorosin amine was used as a capping agent for end-capping.

3. The method of claim 2, wherein the bio-based water repellent is prepared by the steps of: The reaction of polyols with dimethyl carbonate uses an inorganic base as a catalyst; And / or, the molar ratio of the hydroxyl group of the polyol to dimethyl carbonate is 1:(1-2).

4. The method of claim 3, wherein the bio-based water repellent is prepared by the steps of: The inorganic base is potassium carbonate or sodium carbonate; And / or, the reaction of polyols with dimethyl carbonate is carried out at 70-100°C for 12-48 hours; And / or, the amount of the inorganic base used is 0.1-0.5 wt% of the total amount of polyol and dimethyl carbonate; And / or, the reaction temperature for the ring-opening polymerization of cyclic carbonates with diamines is 100-140℃; And / or, the molar ratio of the cyclic carbonate group to the amino group of the diamine in the cyclic carbonate is (1.1-1.5):1; And / or, the molar ratio of the cyclic carbonate group to the amino group of the dehydrorosinamine in the cyclic carbonate is (4-8):

1.

5. The method for preparing the bio-based water-repellent agent according to claim 2, characterized in that, The bio-based water-repellent agent is formulated into a solution using alcohol solvents, with a solid content of 10-40%. And / or, the alcohol solvent includes one or more combinations of methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, and tert-butanol.

6. The application of the bio-based water-repellent agent as described in claim 1 in the field of fabric finishing.

7. A water-repellent fabric, obtained by impregnating the fabric with the bio-based water-repellent agent as described in claim 1, followed by a one-dip-one-roll process and then drying and shaping; wherein, The fabric is selected from nylon.

8. The application of the water-repellent fabric as described in claim 7 in the manufacture of outdoor clothing.

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