A moisture-absorbing and heat-generating thermal fabric made of kapok and its preparation method

Abstract

This application relates to the field of textile fabric technology, and in particular to a kapok moisture-absorbing and heat-generating warm fabric and its preparation method. The fabric uses kapok fiber as the main raw material, combined with cotton fiber, moisture-absorbing and heat-generating modified polyester fiber, and spandex filament. It is processed using needle-punching nonwoven technology, and then impregnated with a composite modification treatment liquid composed of chitosan, polyethylene glycol 400, and nano-silica, etc., to form a stable moisture-absorbing and heat-generating functional layer on the fiber surface through curing and cross-linking. This invention effectively solves the problems of poor cohesion of kapok fibers and serious yarn fly, and the prepared fabric has both excellent moisture-absorbing and heat-generating properties and warming properties. The moisture-absorbing and heat-generating temperature rise value reaches 3.5~5.5℃, and the warmth retention rate is 35~45%, while maintaining good air permeability and moisture permeability.

Description

Technical Field

[0001] This invention relates to the field of textile technology, and in particular to a moisture-absorbing, heat-generating, and warm fabric made of kapok and its preparation method. Background Technology

[0002] Kapok fiber, due to its lightweight, hollow, and warm properties, has broad application prospects in the textile industry. However, the smooth surface and poor cohesion of natural kapok fiber make it prone to fly waste during spinning, resulting in low yarn strength and poor yarn evenness, which severely restricts the large-scale production of pure kapok fabrics. Existing technologies mostly use blending kapok with fibers such as cotton and polyester to improve spinning performance, but the blending ratio is limited, making it difficult to fully utilize the natural advantages of kapok fiber.

[0003] Regarding moisture-wicking and heat-generating functions, traditional thermal fabrics primarily rely on still air layers for insulation, resulting in rapid heat loss and significant dependence on ambient humidity. While some moisture-wicking and heat-generating fiber fabrics have emerged on the market, their heat-generating effects are generally weak, and they suffer from insufficient heat retention, making it difficult to meet the long-term warmth requirements in cold environments. Furthermore, the functionality of some moisture-wicking and heat-generating fabrics gradually diminishes after repeated use, and their durability needs improvement.

[0004] In terms of fabric manufacturing processes, conventional spinning-weaving-finishing processes do not adequately protect kapok fibers, making them prone to damage and breakage during processing. This results in a decrease in the fluffiness and warmth of the finished fabric. Existing finishing techniques often use coatings or impregnation to impart functionality to the fabric, but these methods can easily clog the hollow structure of the fibers, reducing the fabric's breathability and moisture permeability, which is detrimental to the regulation of human body temperature and humidity comfort.

[0005] Therefore, developing fabrics and their preparation technologies that can fully utilize the advantages of kapok fibers, possess excellent moisture absorption and heat generation properties, and provide long-lasting warmth are the core requirements for enhancing the competitiveness of kapok textile products. Summary of the Invention

[0006] The purpose of this invention is to provide a kapok moisture-absorbing and heat-generating thermal fabric and its preparation method, so as to solve the problems existing in the prior art, such as poor cohesion of kapok fibers, serious yarn fly, weak and insufficient heat generation effect of traditional moisture-absorbing and heat-generating fabrics, and the tendency of finishing processes to clog the hollow structure of fibers, resulting in a decrease in air permeability and moisture permeability.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A method for preparing a moisture-absorbing, heat-generating, and warm fabric made of kapok includes the following steps: (1) Weigh the raw materials by weight: 65-70 parts by weight of kapok fiber, 15-20 parts by weight of cotton fiber, 8-12 parts by weight of moisture-absorbing and heat-generating modified polyester fiber, and 3-5 parts by weight of spandex filament. Mix them in order of fiber length from long to short to obtain mixed fiber raw materials. (2) The mixed fiber raw material is fed into a carding machine for opening and carding. The cylinder speed of the carding machine is controlled at 350~400 r / min, the doffer speed is controlled at 25~35 r / min, and the carding is done 3~4 times to obtain a uniformly distributed fiber web. The fiber web is then laid up in multiple layers by a web laying machine. The number of web layers is 6~8, and the total thickness is controlled at 15~20 mm to obtain a layered fiber web. (3) The lay-up fiber web is fed into a needle punching machine for pre-needling. The needle punching density is 800~1000 needles / cm², the needle penetration depth is 8~12mm, and the needle punching frequency is 800~1000 times / min to form a fiber web matrix with a preliminary entanglement structure. Then, the main needle punching is performed. The needle punching density is 1500~2000 needles / cm², the needle penetration depth is 10~14mm, and the needle punching frequency is 1200~1500 times / min to fully entangle the fibers to form a three-dimensional network structure and obtain the needle punched nonwoven fabric matrix. (4) The needle-punched nonwoven fabric matrix is ​​immersed in a modification treatment solution for impregnation treatment. The modification treatment solution includes the following components by weight: 3-5 parts by weight of chitosan, 1-2 parts by weight of polyethylene glycol 400, 0.5-1 parts by weight of nano-silica, 0.3-0.5 parts by weight of sodium polyacrylate, and 0.2-0.4 parts by weight of crosslinking agent. The bath ratio is 1:15-1:20, the impregnation temperature is 25-35℃, the impregnation time is 20-30min, and after impregnation, it is rolled. The rolling pressure is 0.3-0.5MPa, and the rolling rate is 60-70%. (5) The impregnated matrix is ​​placed in an oven for curing and crosslinking treatment. The oven temperature is 120~140℃ and the drying time is 8~12min, so that the modified treatment liquid forms a stable moisture-absorbing and heat-generating functional layer on the fiber surface. Then, heat setting treatment is performed. The heat setting temperature is 150~170℃ and the setting time is 30~45s. The overfeed rate is 8~12%. (6) The heat-set fabric is softened and finished. The softening liquid includes 2-4 parts by weight of softener and 0.5-1 parts by weight of antistatic agent. The softening treatment temperature is 40-50℃ and the treatment time is 15-20min. Finally, a pre-shrinking treatment is performed with a pre-shrinking rate of 3-5%, and the final product is a cotton moisture-absorbing and heat-generating warm fabric.

[0008] Furthermore, the kapok fiber mentioned in step (1) is a kapok fiber with a length of 20~28mm and a linear density of 0.8~1.2dtex.

[0009] Furthermore, the cotton fiber mentioned in step (1) is a cotton fiber with a length of 28~32mm and a micronaire value of 3.8~4.2.

[0010] Furthermore, the moisture-absorbing and heat-generating modified polyester fiber mentioned in step (1) is a moisture-absorbing and heat-generating modified polyester fiber with a cross-shaped cross section and a linear density of 1.2~1.6dtex.

[0011] Furthermore, the chitosan in step (4) is chitosan with a degree of deacetylation of 85-90% and a viscosity of 50-100 mPa·s.

[0012] Furthermore, the nano-silica in step (4) is nano-silica with a particle size of 20~30nm.

[0013] Furthermore, the crosslinking agent in step (4) is an epoxy resin crosslinking agent prepared by reacting epichlorohydrin with diethanolamine.

[0014] Furthermore, the curing and crosslinking treatment in step (5) is carried out under a nitrogen protective atmosphere with a nitrogen flow rate of 2~3L / min.

[0015] Furthermore, the softener mentioned in step (6) is a polysiloxane softener with a silicon content of 18-22%.

[0016] A moisture-absorbing and heat-generating thermal fabric made of kapok is prepared by the above-mentioned method. The fabric has a unit area mass of 180~220g / m², a thickness of 2.5~3.5mm, an air permeability of 150~200mm / s, a moisture permeability of 3500~4500g / (m²·24h), a moisture absorption and heat generation temperature rise of 3.5~5.5℃, and a thermal insulation rate of 35~45%.

[0017] Compared with the prior art, the beneficial effects achieved by the present invention are: This invention uses kapok fiber as the main raw material, and through blending and spinning with cotton fiber, moisture-absorbing and heat-generating modified polyester fiber and spandex filament, combined with needle-punched nonwoven technology and finishing process, a kapok fabric with excellent moisture-absorbing and heat-generating properties and warmth retention properties is prepared. This solves the problems of poor cohesion of kapok fiber and serious yarn fly in the prior art, and realizes the efficient application of kapok fiber in the field of thermal insulation fabrics.

[0018] This invention uses 65-70 parts by weight of kapok fiber as the main material, giving full play to the natural advantages of kapok fiber's hollow, lightweight, and good warmth retention; 15-20 parts by weight of cotton fiber improves the cohesion between fibers and yarn strength, reducing fly waste during the spinning process; 8-12 parts by weight of moisture-absorbing and heat-generating modified polyester fiber provides moisture-absorbing and heat-generating functions; and 3-5 parts by weight of spandex filament gives the fabric good elasticity and recovery properties. The synergistic effect of the three fibers fundamentally improves the spinning performance and functional properties of pure kapok fabric.

[0019] This invention uses needle-punching reinforcement technology to replace the traditional spinning-weaving process, avoiding repeated stretching and friction damage to kapok fibers during the weaving process, effectively protecting the hollow structure of the fibers, and maximizing the retention of the kapok fiber's fluffiness and warmth; the three-dimensional mesh structure formed by needle punching creates a large number of static air layers between the fibers, further enhancing the fabric's heat retention effect.

[0020] This invention employs a composite modification treatment solution composed of chitosan, polyethylene glycol 400, nano-silica, sodium polyacrylate, and a crosslinking agent to impregnate the needle-punched matrix. Chitosan forms a dense adsorption layer on the fiber surface, nano-silica provides a large number of microporous structures and adsorption sites, polyethylene glycol 400 enhances the moisture absorption performance of the fiber, and sodium polyacrylate forms a stable moisture-absorbing and heat-generating functional layer on the fiber surface through a crosslinking reaction. This functional layer not only absorbs moisture emitted by human skin and converts it into heat energy, but also does not clog the hollow structure of the fiber, ensuring the breathability and moisture permeability of the fabric and achieving a balance between moisture absorption and heat generation and thermal and moisture comfort.

[0021] This invention uses a curing and cross-linking process to form a stable cross-linking network on the fiber surface with the modified treatment liquid, ensuring that the moisture-absorbing and heat-generating functional layer is not easily detached during repeated use and washing, thus improving the durability of the fabric. The heat setting process further stabilizes the size and appearance of the fabric, the softening finish gives the fabric a comfortable feel, and the pre-shrinking process ensures the dimensional stability of the fabric during subsequent use. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall process flow of the preparation method of the present invention; Figure 2 This is a schematic diagram of the equipment layout for the needle reinforcement process in this invention; Figure 3 This is a schematic diagram of the immersion treatment device in the present invention; Figure 4 This is an enlarged schematic diagram of the fabric structure obtained by the present invention; Figure 5 This is a schematic diagram illustrating the principle of the interaction between the modified treatment liquid and the fiber surface of the present invention. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] To more clearly illustrate the method provided by the present invention, the following embodiments are provided in detail. The testing methods for various indicators of the kapok moisture-absorbing and heat-generating thermal insulation fabric produced in the following embodiments are as follows: Moisture absorption and heat generation performance test: The test was conducted in accordance with the method of GB / T35263-2017 "Test and evaluation of the contact warmth performance of textiles". After the sample was conditioned for 24 hours at 20℃ and 65% relative humidity, it was taken out and quickly covered on the test plate at a constant temperature of 37℃. The temperature change curve within 30 seconds was recorded using a contact warmth tester, and the maximum temperature rise value was calculated.

[0025] Thermal insulation performance test: According to GB / T11048-2018 "Determination of physiological comfort and thermal insulation of textiles", a flat plate thermal insulation instrument was used for testing. The test temperature was 20℃, the relative humidity was 65%, the hot plate temperature was 36℃, the sample size was 30cm×30cm, and the thermal insulation rate was calculated.

[0026] Air permeability test: The air permeability rate was measured using an air permeability tester under a pressure difference of 100 Pa, according to GB / T5453-1997 "Textiles - Determination of Air Permeability of Fabrics". Moisture permeability test: The test was conducted according to GB / T12704.1-2009 "Textiles - Test Methods for Moisture Permeability of Fabrics - Part 1: Moisture Absorption Method", and the amount of moisture permeated per unit time was calculated.

[0027] Unit area mass test: The test shall be conducted in accordance with GB / T4669-2008 "Determination of unit length mass and unit area mass of textiles and woven fabrics". Example 1:

[0028] (1) Weigh the raw materials according to the following weight parts: 65 parts by weight of kapok fiber (length 20mm, linear density 0.8dtex), 15 parts by weight of cotton fiber (length 28mm, micronaire value 3.8), 8 parts by weight of moisture-absorbing and heat-generating modified polyester fiber (cross-section, linear density 1.2dtex), and 3 parts by weight of spandex filament. Mix them in order of fiber length from long to short to obtain mixed fiber raw materials. (2) The mixed fiber raw material is fed into a carding machine for opening and carding. The speed of the carding machine cylinder is controlled at 350 r / min, the speed of the doffer is controlled at 25 r / min, and the carding is done 3 times to obtain a uniformly distributed fiber web. The fiber web is then laid up in multiple layers by a web laying machine. The number of web laying layers is 6, and the total thickness is controlled at 15 mm to obtain a layered fiber web. (3) The lay-up fiber web is fed into a needle punching machine for pre-needling. The needle punching density is 800 needles / cm², the needle penetration depth is 8mm, and the needle punching frequency is 800 times / min to form a fiber web matrix with a preliminary entangled structure. Then, the main needle punching is performed with a needle punching density of 1500 needles / cm², a needle penetration depth of 10mm, and a needle punching frequency of 1200 times / min to fully entangle the fibers and form a three-dimensional network structure to obtain the needle punched nonwoven fabric matrix. (4) The needle-punched nonwoven fabric matrix is ​​immersed in the modification treatment solution for impregnation treatment. The modification treatment solution includes the following components by weight: 3 parts by weight of chitosan (degree of deacetylation of 85%, viscosity of 50 mPa·s), 1 part by weight of polyethylene glycol 400, 0.5 parts by weight of nano silica (particle size of 20 nm), 0.3 parts by weight of sodium polyacrylate, and 0.2 parts by weight of crosslinking agent (epoxy resin crosslinking agent obtained by reacting epichlorohydrin with diethanolamine). The bath ratio is 1:15, the impregnation temperature is 25℃, the impregnation time is 20 min, and after impregnation, it is rolled. The rolling pressure is 0.3 MPa and the rolling rate is 60%. (5) The impregnated matrix is ​​placed in an oven for curing and crosslinking treatment. The oven temperature is 120℃ and the drying time is 8min. The treatment is carried out under a nitrogen protective atmosphere with a nitrogen flow rate of 2L / min, so that the modified treatment liquid forms a stable moisture-absorbing and heat-generating functional layer on the fiber surface. Then, heat setting treatment is performed at a temperature of 150℃ and a setting time of 30s, with a setting overfeed rate of 8%. (6) The heat-set fabric is softened and finished. The softening liquid includes 2 parts by weight of softener (polysiloxane softener with 18% silicon content) and 0.5 parts by weight of antistatic agent. The softening treatment temperature is 40℃ and the treatment time is 15min. Finally, a pre-shrinking treatment is performed with a pre-shrinking rate of 3%, and the final product is a cotton moisture-absorbing and heat-generating warm fabric. Example 2:

[0029] (1) Weigh the raw materials by weight: 67 parts by weight of kapok fiber (length 23mm, linear density 1.0dtex), 17 parts by weight of cotton fiber (length 30mm, micron value 4.0), 10 parts by weight of moisture-absorbing and heat-generating modified polyester fiber (cross-section, linear density 1.4dtex), and 4 parts by weight of spandex filament. Mix them in order of fiber length from long to short to obtain mixed fiber raw materials. (2) The mixed fiber raw material is fed into a carding machine for opening and carding. The speed of the carding machine cylinder is controlled at 370 r / min, the speed of the doffer is controlled at 30 r / min, and the carding is done 3 times to obtain a uniformly distributed fiber web. The fiber web is then laid up in multiple layers by a web laying machine. The number of web laying layers is 7, and the total thickness is controlled at 18 mm to obtain a layered fiber web. (3) The lay-up fiber web is fed into a needle punching machine for pre-needling. The needle punching density is 900 needles / cm², the needle penetration depth is 10mm, and the needle punching frequency is 900 times / min to form a fiber web matrix with a preliminary entangled structure. Then, the main needle punching is performed with a needle punching density of 1700 needles / cm², a needle penetration depth of 12mm, and a needle punching frequency of 1300 times / min to fully entangle the fibers and form a three-dimensional network structure to obtain the needle punched nonwoven fabric matrix. (4) The needle-punched nonwoven fabric matrix is ​​immersed in the modification treatment solution for impregnation treatment. The modification treatment solution includes the following components by weight: 4 parts by weight of chitosan (degree of deacetylation of 87%, viscosity of 75 mPa·s), 1.5 parts by weight of polyethylene glycol 400, 0.75 parts by weight of nano silica (particle size of 25 nm), 0.4 parts by weight of sodium polyacrylate, and 0.3 parts by weight of crosslinking agent (epoxy resin crosslinking agent obtained by reacting epichlorohydrin with diethanolamine). The bath ratio is 1:17, the impregnation temperature is 30℃, the impregnation time is 25 min, and after impregnation, it is rolled. The rolling pressure is 0.4 MPa and the rolling rate is 65%. (5) The impregnated matrix is ​​placed in an oven for curing and crosslinking treatment. The oven temperature is 130℃ and the drying time is 10min. The treatment is carried out under a nitrogen protective atmosphere with a nitrogen flow rate of 2.5L / min, so that the modified treatment liquid forms a stable moisture-absorbing and heat-generating functional layer on the fiber surface. Then, heat setting treatment is performed at a temperature of 160℃ and a setting time of 38s. The overfeed rate for setting is 10%. (6) The heat-set fabric is softened and finished. The softening liquid includes 3 parts by weight of softener (polysiloxane softener with 20% silicon content) and 0.75 parts by weight of antistatic agent. The softening treatment temperature is 45℃ and the treatment time is 18min. Finally, a pre-shrinking treatment is performed with a pre-shrinking rate of 4%, and the final product is a kapok moisture-absorbing and heat-generating warm fabric. Example 3:

[0030] (1) Weigh the raw materials by weight: 68 parts by weight of kapok fiber (length 25mm, linear density 1.1dtex), 18 parts by weight of cotton fiber (length 31mm, micronaire value 4.1), 10 parts by weight of moisture-absorbing and heat-generating modified polyester fiber (cross-section, linear density 1.5dtex), and 4 parts by weight of spandex filament. Mix them in order of fiber length from long to short to obtain mixed fiber raw materials. (2) The mixed fiber raw material is fed into a carding machine for opening and carding. The speed of the carding machine cylinder is controlled at 380 r / min, the speed of the doffer is controlled at 32 r / min, and the number of carding times is 4 times to obtain a uniformly distributed fiber web. The fiber web is then laid up in multiple layers by a web laying machine. The number of web laying layers is 7, and the total thickness is controlled at 18 mm to obtain a layered fiber web. (3) The lay-up fiber web is fed into a needle punching machine for pre-needling. The needle punching density is 950 needles / cm², the needle penetration depth is 10mm, and the needle punching frequency is 950 times / min to form a fiber web matrix with a preliminary entangled structure. Then, the main needle punching is performed with a needle punching density of 1800 needles / cm², a needle penetration depth of 12mm, and a needle punching frequency of 1400 times / min to fully entangle the fibers and form a three-dimensional network structure to obtain the needle punched nonwoven fabric matrix. (4) The needle-punched nonwoven fabric matrix is ​​immersed in the modification treatment solution for impregnation treatment. The modification treatment solution includes the following components by weight: 4.5 parts by weight of chitosan (degree of deacetylation of 88%, viscosity of 85 mPa·s), 1.8 parts by weight of polyethylene glycol 400, 0.8 parts by weight of nano silica (particle size of 28 nm), 0.45 parts by weight of sodium polyacrylate, and 0.35 parts by weight of crosslinking agent (epoxy resin crosslinking agent obtained by reacting epichlorohydrin with diethanolamine). The bath ratio is 1:18, the impregnation temperature is 32℃, the impregnation time is 27 min, and after impregnation, it is rolled. The rolling pressure is 0.45 MPa and the rolling rate is 68%. (5) The impregnated matrix is ​​placed in an oven for curing and crosslinking treatment. The oven temperature is 135℃ and the drying time is 11min. The treatment is carried out under a nitrogen protective atmosphere with a nitrogen flow rate of 2.5L / min, so that the modified treatment liquid forms a stable moisture-absorbing and heat-generating functional layer on the fiber surface. Then, heat setting treatment is performed at a temperature of 165℃ and a setting time of 40s. The overfeed rate for setting is 10%. (6) The heat-set fabric is softened and finished. The softening liquid includes 3.5 parts by weight of softener (polysiloxane softener with 21% silicon content) and 0.8 parts by weight of antistatic agent. The softening treatment temperature is 48℃ and the treatment time is 19min. Finally, a pre-shrinking treatment is performed with a pre-shrinking rate of 4%, and the final product is a kapok moisture-absorbing and heat-generating warm fabric. Example 4:

[0031] (1) Weigh the raw materials by weight: 69 parts by weight of kapok fiber (length 26mm, linear density 1.1dtex), 19 parts by weight of cotton fiber (length 31mm, micronaire value 4.1), 11 parts by weight of moisture-absorbing and heat-generating modified polyester fiber (cross-section, linear density 1.5dtex), and 4.5 parts by weight of spandex filament. Mix them in order of fiber length from long to short to obtain mixed fiber raw materials. (2) The mixed fiber raw material is fed into a carding machine for opening and carding. The speed of the carding machine cylinder is controlled at 390 r / min, the speed of the doffer is controlled at 33 r / min, and the number of carding times is 4 times to obtain a uniformly distributed fiber web. The fiber web is then laid up in multiple layers by a web laying machine. The number of web laying layers is 8, and the total thickness is controlled at 19 mm to obtain a layered fiber web. (3) The lay-up fiber web is fed into a needle punching machine for pre-needling. The needle punching density is 980 needles / cm², the needle penetration depth is 11mm, and the needle punching frequency is 980 times / min to form a fiber web matrix with a preliminary entangled structure. Then, the main needle punching is performed with a needle punching density of 1900 needles / cm², a needle penetration depth of 13mm, and a needle punching frequency of 1450 times / min to fully entangle the fibers and form a three-dimensional network structure to obtain the needle punched nonwoven fabric matrix. (4) The needle-punched nonwoven fabric matrix was immersed in the modification treatment solution for impregnation treatment. The modification treatment solution included the following components by weight: 4.8 parts by weight of chitosan (degree of deacetylation of 89%, viscosity of 90 mPa·s), 1.9 parts by weight of polyethylene glycol 400, 0.9 parts by weight of nano silica (particle size of 28 nm), 0.48 parts by weight of sodium polyacrylate, and 0.38 parts by weight of crosslinking agent (epoxy resin crosslinking agent obtained by reacting epichlorohydrin with diethanolamine). The bath ratio was 1:19, the impregnation temperature was 33℃, the impregnation time was 28 min, and after impregnation, it was rolled. The rolling pressure was 0.48 MPa and the rolling rate was 69%. (5) The impregnated matrix is ​​placed in an oven for curing and crosslinking treatment. The oven temperature is 138℃ and the drying time is 11min. The treatment is carried out under a nitrogen protective atmosphere with a nitrogen flow rate of 2.8L / min, so that the modified treatment liquid forms a stable moisture-absorbing and heat-generating functional layer on the fiber surface. Then, heat setting treatment is performed at a temperature of 168℃ and a setting time of 42s. The overfeed rate for setting is 11%. (6) The heat-set fabric is softened and finished. The softening liquid includes 3.8 parts by weight of softener (polysiloxane softener with 21% silicon content) and 0.9 parts by weight of antistatic agent. The softening treatment temperature is 49℃ and the treatment time is 19min. Finally, a pre-shrinking treatment is performed with a pre-shrinking rate of 4.5%, and the final product is a kapok moisture-absorbing and heat-generating warm fabric. Example 5:

[0032] (1) Weigh the raw materials by weight: 70 parts by weight of kapok fiber (length 28mm, linear density 1.2dtex), 20 parts by weight of cotton fiber (length 32mm, micronaire value 4.2), 12 parts by weight of moisture-absorbing and heat-generating modified polyester fiber (cross-section, linear density 1.6dtex), and 5 parts by weight of spandex filament. Mix them in order of fiber length from long to short to obtain mixed fiber raw materials. (2) The mixed fiber raw material is fed into a carding machine for opening and carding. The speed of the carding machine cylinder is controlled at 400 r / min, the speed of the doffer is controlled at 35 r / min, and the carding is done 4 times to obtain a uniformly distributed fiber web. The fiber web is then laid up in multiple layers by a web laying machine. The number of web laying layers is 8, and the total thickness is controlled at 20 mm to obtain a layered fiber web. (3) The lay-up fiber web is fed into a needle punching machine for pre-needling. The needle punching density is 1000 needles / cm², the needle penetration depth is 12mm, and the needle punching frequency is 1000 times / min to form a fiber web matrix with a preliminary entanglement structure. Then, the main needle punching is performed with a needle punching density of 2000 needles / cm², a needle penetration depth of 14mm, and a needle punching frequency of 1500 times / min to fully entangle the fibers and form a three-dimensional network structure to obtain the needle punched nonwoven fabric matrix. (4) The needle-punched nonwoven fabric matrix is ​​immersed in the modification treatment solution for impregnation treatment. The modification treatment solution includes the following components by weight: 5 parts by weight of chitosan (degree of deacetylation of 90%, viscosity of 100 mPa·s), 2 parts by weight of polyethylene glycol 400, 1 part by weight of nano silica (particle size of 30 nm), 0.5 parts by weight of sodium polyacrylate, and 0.4 parts by weight of crosslinking agent (epoxy resin crosslinking agent obtained by reacting epichlorohydrin with diethanolamine). The bath ratio is 1:20, the impregnation temperature is 35℃, the impregnation time is 30 min, and after impregnation, it is rolled. The rolling pressure is 0.5 MPa and the rolling rate is 70%. (5) The impregnated matrix is ​​placed in an oven for curing and crosslinking treatment. The oven temperature is 140℃ and the drying time is 12min. The treatment is carried out under a nitrogen protective atmosphere with a nitrogen flow rate of 3L / min, so that the modified treatment liquid forms a stable moisture-absorbing and heat-generating functional layer on the fiber surface. Then, heat setting treatment is performed at a temperature of 170℃ and a setting time of 45s. The overfeed rate for setting is 12%. (6) The heat-set fabric is softened and finished. The softening liquid includes 4 parts by weight of softener (polysiloxane softener with 22% silicon content) and 1 part by weight of antistatic agent. The softening treatment temperature is 50℃ and the treatment time is 20min. Finally, a pre-shrinking treatment is performed with a pre-shrinking rate of 5%, and the final product is a kapok moisture-absorbing and heat-generating warm fabric.

[0033] Comparative Example 1 The difference between Comparative Example 1 and Example 3 is that conventional polyester fiber is used instead of moisture-absorbing and heat-generating modified polyester fiber, while the other steps are the same as in Example 3.

[0034] Comparative Example 2 The difference between Comparative Example 2 and Example 3 is that the needle punching process is omitted, and the fabric is prepared directly by carding-web laying-heat setting process. The remaining steps are the same as in Example 3.

[0035] Comparative Example 3 The difference between Comparative Example 3 and Example 3 is that the impregnation step is omitted, and the modification solution impregnation and curing crosslinking treatment are not performed. The remaining steps are the same as in Example 3.

[0036] Comparative Example 4 The difference between Comparative Example 4 and Example 3 is that the curing and crosslinking treatment is replaced with conventional drying treatment, and the oven temperature is set to 80°C for 30 minutes. The remaining steps are the same as in Example 3.

[0037] Comparative Example 5 The difference between Comparative Example 5 and Example 3 is that an equal amount of cotton fiber is used to replace the moisture-absorbing and heat-generating modified polyester fiber. That is, the formula is 65 parts by weight of kapok fiber, 25 parts by weight of cotton fiber, and 4 parts by weight of spandex filament. The remaining steps are the same as in Example 3.

[0038] Example of effect Table 1 below presents the performance analysis results of the kapok moisture-absorbing and heat-generating thermal insulation fabrics of Examples 1 to 5 and Comparative Examples 1 to 5 of the present invention.

[0039] Table 1

[0040] A comparison of the experimental data on the moisture absorption and heat generation values ​​of the embodiments and comparative examples reveals that the present invention utilizes the synergistic effect of moisture-absorbing and heat-generating modified polyester fibers and composite modification treatment liquid. The cross-shaped cross-sectional structure of the moisture-absorbing and heat-generating modified polyester fibers increases the specific surface area of ​​the fibers, providing more moisture absorption sites. Chitosan in the composite modification treatment liquid forms a dense adsorption layer on the fiber surface, nano-silica provides a large number of microporous structures and adsorption sites, polyethylene glycol 400 enhances the moisture absorption performance of the fibers, and sodium polyacrylate forms a stable moisture-absorbing and heat-generating functional layer through a cross-linking reaction, synergistically endowing the fabric with excellent moisture absorption and heat generation properties. Comparative Example 1 uses conventional polyester fibers that lack moisture absorption and heat generation functions, Comparative Example 3 omits the impregnation treatment, resulting in the failure to form a functional layer, and Comparative Example 5 uses cotton fibers instead of moisture-absorbing and heat-generating modified polyester fibers. The moisture absorption and heat generation values ​​of all three are significantly lower than those of the embodiments of the present invention.

[0041] A comparison of the experimental data on air permeability and moisture permeability of the examples and comparative examples reveals that the present invention uses needle-punched nonwoven technology to replace the traditional spinning-weaving process, avoiding repeated stretching and friction damage to the kapok fibers during the weaving process, effectively protecting the hollow structure of the fibers, and maximizing the air permeability and moisture permeability of the fabric. At the same time, the composite modification treatment liquid is applied by impregnation rather than coating, which does not clog the hollow structure of the fibers and ensures the air permeability and moisture permeability of the fabric. In contrast, the omission of the needle-punching process in Comparative Example 2 resulted in a lack of effective entanglement structure between the fibers, making the hollow structure of the fibers easily damaged in subsequent processing, and causing a decrease in both air permeability and moisture permeability.

[0042] A comparison of the experimental data on the insulation efficiency of the embodiments and comparative examples reveals that the three-dimensional mesh structure formed by needle punching in this invention creates a large number of static air layers between the fibers, significantly enhancing the insulation effect of the fabric. The hollow and lightweight characteristics of the kapok fiber itself, combined with the needle-punched three-dimensional mesh structure, further improve the insulation performance. Comparative example 2, by omitting the needle punching process, results in the inability to form an effective three-dimensional entanglement structure between the fibers, and the insulation efficiency is only 28%, significantly lower than that of the embodiments of this invention.

[0043] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A method for preparing a moisture-absorbing, heat-generating, and warm fabric made of kapok, characterized in that, Includes the following steps: (1) Weigh the raw materials by weight: 65-70 parts by weight of kapok fiber, 15-20 parts by weight of cotton fiber, 8-12 parts by weight of moisture-absorbing and heat-generating modified polyester fiber, and 3-5 parts by weight of spandex filament. Mix them in order of fiber length from long to short to obtain mixed fiber raw materials. (2) The mixed fiber raw material is fed into a carding machine for opening and carding. The cylinder speed of the carding machine is controlled at 350~400 r / min, the doffer speed is controlled at 25~35 r / min, and the carding is done 3~4 times to obtain a uniformly distributed fiber web. The fiber web is then laid up in multiple layers by a web laying machine. The number of web layers is 6~8, and the total thickness is controlled at 15~20 mm to obtain a layered fiber web. (3) The lay-up fiber web is fed into a needle punching machine for pre-needling. The needle punching density is 800~1000 needles / cm², the needle penetration depth is 8~12mm, and the needle punching frequency is 800~1000 times / min to form a fiber web matrix with a preliminary entanglement structure. Then, the main needle punching is performed. The needle punching density is 1500~2000 needles / cm², the needle penetration depth is 10~14mm, and the needle punching frequency is 1200~1500 times / min to fully entangle the fibers to form a three-dimensional network structure and obtain the needle punched nonwoven fabric matrix. (4) The needle-punched nonwoven fabric matrix is ​​immersed in a modification treatment solution for impregnation treatment. The modification treatment solution includes the following components by weight: 3-5 parts by weight of chitosan, 1-2 parts by weight of polyethylene glycol 400, 0.5-1 parts by weight of nano-silica, 0.3-0.5 parts by weight of sodium polyacrylate, and 0.2-0.4 parts by weight of crosslinking agent. The bath ratio is 1:15-1:20, the impregnation temperature is 25-35℃, the impregnation time is 20-30min, and after impregnation, it is rolled. The rolling pressure is 0.3-0.5MPa, and the rolling rate is 60-70%. (5) The impregnated matrix is ​​placed in an oven for curing and crosslinking treatment. The oven temperature is 120~140℃ and the drying time is 8~12min, so that the modified treatment liquid forms a stable moisture-absorbing and heat-generating functional layer on the fiber surface. Then, heat setting treatment is performed. The heat setting temperature is 150~170℃ and the setting time is 30~45s. The overfeed rate is 8~12%. (6) The heat-set fabric is softened and finished. The softening liquid includes 2-4 parts by weight of softener and 0.5-1 parts by weight of antistatic agent. The softening treatment temperature is 40-50℃ and the treatment time is 15-20min. Finally, a pre-shrinking treatment is performed with a pre-shrinking rate of 3-5%, and the final product is a cotton moisture-absorbing and heat-generating warm fabric.

2. The method for preparing a moisture-absorbing, heat-generating, and warm fabric from kapok according to claim 1, characterized in that, The kapok fiber mentioned in step (1) is a kapok fiber with a length of 20~28mm and a linear density of 0.8~1.2dtex.

3. The method for preparing a moisture-absorbing, heat-generating, and warm fabric from kapok according to claim 1, characterized in that, The cotton fiber mentioned in step (1) is a cotton fiber with a length of 28~32mm and a micronaire value of 3.8~4.

2.

4. The method for preparing a moisture-absorbing, heat-generating, and warm fabric from kapok according to claim 1, characterized in that, The moisture-absorbing and heat-generating modified polyester fiber mentioned in step (1) is a moisture-absorbing and heat-generating modified polyester fiber with a cross-shaped cross section and a linear density of 1.2~1.6dtex.

5. The method for preparing a moisture-absorbing, heat-generating, and warm fabric from kapok according to claim 1, characterized in that, The chitosan in step (4) is chitosan with a degree of deacetylation of 85-90% and a viscosity of 50-100 mPa·s.

6. The method for preparing a moisture-absorbing, heat-generating, and warm fabric from kapok according to claim 1, characterized in that, The nano-silica mentioned in step (4) is nano-silica with a particle size of 20~30nm.

7. The method for preparing a moisture-absorbing, heat-generating, and warm fabric from kapok according to claim 1, characterized in that, The crosslinking agent mentioned in step (4) is an epoxy resin crosslinking agent prepared by reacting epichlorohydrin with diethanolamine.

8. The method for preparing a moisture-absorbing, heat-generating, and warm fabric from kapok according to claim 1, characterized in that, The curing and crosslinking treatment in step (5) is carried out under a nitrogen protective atmosphere with a nitrogen flow rate of 2~3L / min.

9. The method for preparing a moisture-absorbing, heat-generating, and warm fabric from kapok according to claim 1, characterized in that, The softener mentioned in step (6) is a polysiloxane softener with a silicon content of 18-22%.

10. A moisture-absorbing, heat-generating, and warm fabric made of kapok, prepared by the method according to any one of claims 1 to 9, characterized in that, The fabric has a unit area mass of 180~220g / m², a thickness of 2.5~3.5mm, an air permeability of 150~200mm / s, a moisture permeability of 3500~4500g / (m²·24h), a moisture absorption and heat generation value of 3.5~5.5℃, and a warmth retention rate of 35~45%.

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