Core-spun double-helix built-in coated composite paper yarn and its preparation method

Abstract

The application discloses a core double-helix built-in covered composite paper yarn and a preparation method thereof, and belongs to the technical field of textile processing. The method combines paper strips, non-woven fabrics and filaments organically through innovative double-helix structure design and multi-layer covering technology, and forms a composite yarn with excellent performance. The specific steps include: paper strip preparation, ring twisting of paper strip / filament and non-woven fabric / filament into yarn, doubling and twisting of double-helix core yarn, and short fiber false twist covering into yarn. Compared with the prior art, the application realizes high strength, good air permeability and heat preservation of the yarn by precisely controlling the paper page grammage, fiber type, twist parameter and friction spinning covering process. Moreover, the application not only improves the performance of traditional textile materials, but also expands the application of paper-based materials in the high-end textile field, and promotes the development of the textile industry in the direction of green, efficient and sustainable.

Description

Technical Field

[0001] This invention relates to the field of textile processing technology, and in particular to a core-spun double-helix internally wrapped composite paper yarn and its preparation method. Background Technology

[0002] With the rapid development of the global textile industry, the scale of textile production and consumption has been continuously expanding, but this process has also exposed many resource and environmental problems. On the one hand, a large amount of waste textiles are discarded. According to incomplete statistics, the amount of waste textiles generated each year is extremely considerable. These wastes not only occupy a large amount of land resources but also cause serious environmental pollution. On the other hand, traditional waste textile recycling methods have many limitations. For example, the integrity of fiber length is often destroyed during the recycling process, resulting in most of the longer fibers not being fully utilized, leading to resource waste. In addition, the quality of recycled fibers is inconsistent, making it difficult to meet the stringent requirements of high-end textile products for fiber performance and yarn quality, thus limiting the in-depth application and value enhancement of waste textile recycling in the textile industry.

[0003] Traditional textile materials also have certain limitations in performance. For example, while pure cotton yarn has good skin-friendliness and comfort, its strength and abrasion resistance are relatively poor; while chemical fibers, although high in strength, lack breathability and skin-friendliness. Therefore, developing a new type of composite yarn that combines the advantages of different materials to improve the overall performance of the yarn is an important development direction for the textile industry.

[0004] Chinese invention patent CN118814331A discloses a three-component double-helix fatigue-resistant elastic yarn, its preparation method, and its application. The three-component double-helix fatigue-resistant elastic yarn includes a core yarn, an inner covering yarn, and an outer covering yarn. The core yarn is an elastic yarn, and the inner covering yarn is formed by twisting two parallel PTT / PET composite fibers of different finenesses. In the PTT / PET parallel composite fibers, both the PTT component and the PET component are semi-circular. The finenesses of the two PTT / PET parallel composite fibers are 30D and 50D, respectively. The twist coefficient is 300-400. The preparation method involves first preparing the inner covering yarn, and then sequentially covering the core yarn with the inner covering yarn and the outer covering yarn. The application is for preparing pressure therapy textiles, resulting in pressure therapy textiles that combine high elasticity and fatigue resistance. Although the above-mentioned three-component double-helix fatigue-resistant elastic yarn exhibits excellent performance in terms of high elasticity and fatigue resistance, its structure is relatively complex and relies on specific PTT / PET parallel composite fibers, limiting the diversity of raw materials. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a core-spun double-helix internally wrapped composite paper yarn and its preparation method. Through an innovative double-helix structure and multi-layer wrapping technology, paper strips, non-woven fabric, and filaments are organically combined to form a composite yarn with high strength, good breathability, and heat insulation. At the same time, it expands the application of paper-based materials in the high-end textile field and promotes the green and sustainable development of the textile industry.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0007] A method for preparing a core-spun double-helix internally wrapped composite paper yarn is as follows:

[0008] Step 1, Paper strip preparation: Select 4-6 parts by weight of ultra-short fiber and 50-70 parts by weight of pulp as paper strip raw materials. Remove impurities, bleach with sodium hypochlorite bleaching agent and break down the pulp. Then add 5-10 parts by weight of calcium carbonate and 0.5-2 parts by weight of sizing agent. Finally, add water and mix evenly to obtain a pulp material with a pulp concentration of 0.1-2wt%. Adjust the width of the KLM-CX-2 type paper sheet forming machine to 1-100mm. The wet paper is then pasted on the drying cylinder, and the heat is used to evaporate the remaining moisture, so that the paper sheet is completely dry. The obtained paper sheet is then wound onto a paper strip drum. The paper strip drum is placed on the tension frame of the paper strip cutting machine. The paper sheet is cut into paper strips by the cutting roller. The cut paper strips are separated from the cutting roller by the bundling sheet and wound into a paper strip roll.

[0009] Step 2: Paper strips / filaments and nonwoven fabric / filaments are twisted into yarn by ring spinning: The paper strips prepared in Step 1 are placed on the roving spindles of a ring spinning machine without a drafting system. 1-100 paper strips are unwound and fed into the front roller nip formed by the meshing of the front roller and the front rubber roller on the yarn guide frame via the tension wheel. 1-100 filaments unwound from the roving spindle are also fed into the front roller nip via the tension wheel and merge with the paper strips. The merged filaments and paper strips are output from the roller nip. The output filaments and paper strips are twisted, wound, and stretched by the spindle. The twisted paper strips and filaments form a composite paper strip, which is finally wound into a packaged paper yarn. The composite twisting of viscose nonwoven fabric and filaments is carried out using the same process as that of paper strips and filaments to prepare nonwoven yarn.

[0010] Step 3, Preparation of double helix core yarn: Feed 1-100 pieces of paper yarn prepared in step 2 and 1-100 pieces of nonwoven fabric yarn prepared in step 2 into the front roller nip formed by the meshing of the front roller and the front rubber roller of the ring spinning machine, and perform doubling twisting. The output linear speed is 3-25 m / min, and the spindle rotation speed is 1500-3500 rpm when twisting to form double helix core yarn;

[0011] Step 4, Short Fiber False Twist Covering Yarn: The double helix core yarn prepared in Step 3 is placed on the spindle of the friction spinning machine. Cotton fiber slivers are selected, held by the traction rollers, and fed into the combing rollers by the feed rollers. The short fiber slivers are combed and broken up. The combed short fibers enter between the friction rollers. The double helix core yarn passes through the yarn guide and is twisted and covered by the loose fibers in the friction rollers. The covered yarn is held and conveyed by the first yarn guide roller and the second yarn guide roller. Finally, it is wound on the grooved drum through the yarn guide hole on the yarn guide traverse device to form a double helix core-covered yarn.

[0012] The paper weight in step 1 is 10-200 g / m³. 2 .

[0013] In step 1, the paper tape is cut into strips with a width of 1-10mm by a cutting roller.

[0014] In step 1, the length of the ultrashort fiber is 1-10 mm.

[0015] In step 1, the short fibers are at least one of the following: silver ion fibers, bamboo fibers, chitosan fibers, carbon fibers, stainless steel fibers, polyaniline fibers, polypyrrole fibers, graphene fibers, aramid fibers, polyimide fibers, glass fibers, basalt fibers, cotton fibers, hemp fibers, wool fibers, silk short fibers, viscose fibers, cuprammonium fibers, acetate fibers, polyester fibers, nylon fibers, polypropylene fibers, acrylic fibers, spandex fibers, polylactic acid fibers, and recycled textile fibers.

[0016] In step 2, the filament is at least one of viscose filament, polyethylene filament, basalt filament, polyester filament, nylon filament, spandex filament, polypropylene filament, acrylic filament, polyimide filament, and water-soluble vinylon filament.

[0017] In step 2, the output linear speed is controlled at 3-25 m / min; the spindle rotation speed is 1000-8000 rpm during twisting.

[0018] In step 4, the linear density of the double-helix core-spun yarn is above 25 tex.

[0019] In step 4, the speed of the combing roller is 500-5000 rpm, and the combed short fibers enter the friction roller N with a speed of 500-5000 rpm.

[0020] This invention prepares paper strips with specific properties, serving as a core component of subsequent composite yarns. By selecting short fibers and pulp as raw materials, and after impurity removal, bleaching, and dispersing treatments, calcium carbonate and sizing agents are added to ultimately form paper strips with a specific basis weight and width. The preparation of these paper strips not only provides the basic fiber structure for the composite yarn but also enhances their physical and functional properties through the addition of functional additives. The basis weight and width of the paper strips can be adjusted according to the application requirements of the final yarn, thereby achieving precise control over yarn performance.

[0021] The purpose of ring spinning of paper strips / filaments and nonwoven fabrics / filaments is to combine paper strips with filaments or nonwoven fabrics with filaments to form composite paper strips or nonwoven yarns. Through the twisting process of a ring spinning machine, the paper strips and filaments are tightly bonded, forming composite paper strips with high strength and good flexibility. This process not only enhances the mechanical properties of the paper strips but also improves the overall strength and abrasion resistance of the composite yarn through the addition of filaments. Simultaneously, the combination of nonwoven fabric and filaments further enriches the structure and properties of the yarn, providing a foundation for the subsequent preparation of double-helix core yarns.

[0022] The purpose of preparing the double-helix core yarn is to combine and twist paper yarn and non-woven fabric yarn to form a double-helix core yarn. The design of the double-helix structure is one of the key innovations of this invention. Through the combination and twisting process, the paper yarn and non-woven fabric yarn are tightly wound to form a stable double-helix shape. This structure not only optimizes the mechanical properties of the yarn but also provides a structural basis for subsequent air permeability and heat insulation through the formation of helical gaps. The preparation of the double-helix core yarn is a crucial step in achieving high-performance composite yarns, and the stability of its structure directly affects the final yarn performance.

[0023] The purpose of short-fiber false-twist coated yarn is to coat the double-helix core yarn with short fibers using friction spinning technology, forming the final double-helix core-spun coated yarn. Through friction spinning, short fibers are evenly coated on the surface of the double-helix core yarn, further enhancing the yarn's flexibility and abrasion resistance. Short-fiber coating not only improves the yarn's hand feel and appearance but also enhances its anti-pilling and anti-fuzzing properties by increasing the friction between fibers. Furthermore, different types of fibers can be selected for the short-fiber coating layer as needed, thus giving the yarn more functional properties, such as moisture wicking and antibacterial properties.

[0024] The ingenuity of this invention lies in breaking through the limitations of the single function of traditional textile materials. Through a unique double-helix core yarn + gradient covering structure design, it solves the core contradiction in existing technologies where heat retention and breathability are difficult to improve simultaneously. Specifically, traditional paper-based yarns, due to their simple pore structure, are prone to an imbalance between heat retention and breathability, while non-woven fabrics, due to their excessive density, restrict airflow. This invention innovatively twists paper yarn and non-woven fabric yarn in a double-helix structure. By precisely controlling the weight of the paper sheets, micron-level honeycomb pores are formed to trap stagnant air. Simultaneously, a three-dimensional network of non-woven fabric is used to construct sub-millimeter-level interconnected air channels. Combined with the nano-level surface pores of the friction-spun outer cotton fibers, a three-level gradient pore system is formed. This multi-scale pore architecture reduces heat convection through nanopores, establishes efficient breathable channels through micron-to-sub-millimeter pores, and ensures pore stability by optimizing the twist to create a self-locking effect in the helical structure. This design achieves a golden balance between heat retention and breathability, providing a generational advantage over traditional pure cotton yarn.

[0025] Compared with existing technologies, it has the following advantages:

[0026] 1) This invention, through an innovative double-helix structure and multi-layer coating design, organically combines paper strips, non-woven fabric, and filaments, significantly improving the strength, breathability, and heat retention of the yarn. This composite structure not only optimizes the mechanical properties of the yarn but also increases the tortuosity of the pores through the natural micropores of the paper fibers and the three-dimensional network of the non-woven fabric, extending the air retention time and thus achieving excellent heat retention and breathability.

[0027] 2) This invention uses pulp and short fibers as raw materials, and through optimized processes, transforms short, broken fibers into high-strength composite yarns, solving the problem of the difficulty in utilizing short fibers in traditional textiles and reducing resource waste. At the same time, the preparation process of this composite yarn eliminates the complex processes of drawing, roving drafting, and yarn drafting and twisting in traditional spinning, further shortening the production process, reducing energy consumption and environmental burden, and promoting the textile industry towards a green and sustainable development direction.

[0028] 3) This invention simplifies the production process and improves production efficiency by eliminating the drafting system in traditional spinning and combining it with friction spinning technology. Simultaneously, by precisely controlling process conditions such as paper weight, fiber type, and twist parameters, it achieves precise regulation of yarn performance, making it suitable for large-scale industrial production and yielding significant economic and social benefits. Attached Figure Description

[0029] Figure 1 Figure 1 shows the core of the paper strip and filament composite ring spinning and twisting process in step 2 of Example 1.

[0030] Roving spindle A1; Roving spindle B1; Tension wheel C; Front roller D; Front rubber roller E; Front roller nip F; Spindle H; Paper yarn tube I;

[0031] Figure 2 A diagram illustrating the preparation of the double-helix core yarn in step 3 of Example 1;

[0032] Front roller D; Front rubber roller E; Front roller jaw F; Spindle H;

[0033] Figure 3 Figure 4 of step 4 in Example 1, showing the friction spinning core-spun fabric.

[0034] Friction spinning machine spindle seat J; cotton fiber sliver S1; traction roller K; feed roller L; carding roller M; friction roller N; yarn guide O; first yarn guide roller P; second yarn guide roller Q; yarn guide traverse device R; yarn guide hole S; grooved drum T;

[0035] Figure 4 Yarn model diagram of Example 1;

[0036] S1 - Cotton fiber slivers; F1 - Paper slivers; F2 - Viscose filaments; T1 - Viscose nonwoven fabric; T2 - Viscose filaments;

[0037] Figure 5 A cross-sectional model diagram of the yarn in Example 1;

[0038] S1 - Cotton fiber slivers; F1 - Paper slivers; F2 - Viscose filaments; T1 - Viscose nonwoven fabric; T2 - Viscose filaments;

[0039] Figure 6 Left: Yarn surface of Example 1; Right: Yarn cross-section of Example 1;

[0040] Figure 7 Fabric sample of Example 1. Detailed Implementation

[0041] To better understand the present invention, the following examples further illustrate its content, but the present invention is not limited to the embodiments described below. The described embodiments are merely some embodiments of the present invention, and not all embodiments. The specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention.

[0042] Main source of materials:

[0043] Viscose fiber, thickness: 1.4D, length: 5 (mm), item number: VS200, Shandong Oude Chemical Fiber Products Co., Ltd.

[0044] Pulp, raw material: wheat straw, item number: hh77006875, Binzhou Junda Renewable Source Environmental Protection Fiber Co., Ltd.

[0045] Sizing agent, model: GBS-02, solid content: 22±1%, viscosity: ≤100mPa.s (25℃), Guangzhou Tongda Chemical Engineering Co., Ltd.

[0046] Viscose filament, thickness: 50D, number of holes: 8F, item number: JL5008, Henan Yikepai New Material Co., Ltd.

[0047] Viscose nonwoven fabric, weight: 300 g / m², width: 2 mm, processing method: needle punching.

[0048] Cotton fiber, grade: 3, fiber length: 29mm, moisture regain ≤8.5%, micronaire value: A, Yucheng County Runda Cotton Industry Co., Ltd.

[0049] All other raw materials used in the embodiments and comparative examples of this invention are commercially available products.

[0050] The design concept of this invention is to develop a core-spun double-helix internally wrapped composite paper yarn and its preparation method through innovative structural design and process optimization. Its core lies in utilizing a double-helix structure and multi-layer wrapping technology to organically combine materials such as paper strips, non-woven fabrics, and filaments to form a composite yarn with excellent performance. By precisely controlling the paper weight, fiber type, twist parameters, and friction spinning wrapping process, high strength, good air permeability, and heat insulation of the yarn are achieved. This design not only improves the performance of traditional textile materials but also expands the application of paper-based materials in high-end textile fields, promoting the textile industry towards green, efficient, and sustainable development.

[0051] Example 1

[0052] A method for preparing a core-spun double-helix internally wrapped composite paper yarn is as follows:

[0053] Step 1: Paper strip preparation: 5 kg of viscose fiber and 60 kg of pulp are selected as raw materials for paper strips. Impurities are removed, and the pulp is bleached and broken up using sodium hypochlorite bleaching agent. Then, 8 kg of calcium carbonate and 1 kg of sizing agent are added, and finally water is added and mixed thoroughly to obtain a pulp with a concentration of 0.2 wt%. The width of the KLM-CX-2 type paper sheet forming machine is adjusted to 50 mm. The wet paper is then pasted onto a drying cylinder, where the heat evaporates the remaining moisture, allowing the paper sheet to dry completely, resulting in a basis weight of 30 g / m². 2 The paper sheets are wound onto the paper tape tube; the paper tape tube is placed on the tension frame of the paper strip cutting machine, and the paper sheets are cut into 2mm wide strips by the cutting roller. The cut paper strips are separated from the cutting roller by the splitting plate and wound into a paper strip roll tube.

[0054] Step 2: Paper strip / filament and nonwoven fabric / filament ring twisting into yarn: The paper strip rolls prepared in Step 1 are placed on the roving spindle A1 of the ring spinning machine (without the drafting system). One paper strip is unwound and fed into the front roller nip F formed by the engagement of the front roller D and the front rubber roller E on the yarn guide C. A viscose filament unwound from the roving spindle B1 is also fed into the front roller nip F via the tension roller C. At point F, the filaments merge with the paper strips. The merged filaments and paper strips are output from roller nip F at a linear speed of 10 m / min. The output viscose filaments and paper strips are then twisted, wound, and pulled by spindle H at a rotation speed of 5000 rpm. The twisted paper strips and filaments form a composite paper strip, which is finally wound into a tube of paper yarn I. The composite twisting of viscose nonwoven fabric and viscose filaments uses the same process as that used for paper strips and filaments to prepare nonwoven yarn.

[0055] Step 3, Preparation of double helix core yarn: Feed one piece of paper yarn prepared in step 2 and one piece of nonwoven fabric yarn prepared in step 2 into the front roller nip F formed by the meshing of the front roller D and the front rubber roller E of the ring spinning machine, and perform doubling twisting. The output linear speed is 10 m / min, and the spindle H rotates at 2500 rpm when twisting to form a double helix core yarn.

[0056] Step 4, Short Fiber False Twist Covering Yarn: The double helix core yarn prepared in Step 3 is placed on the spindle seat J of the friction spinning machine. Cotton fiber sliver S1 is selected, held by the traction roller K, and fed into the combing roller M through the feed roller L. The speed of the combing roller M is 3500 rpm, which combs and disperses the short fiber sliver S1. The combed short fibers enter between the friction rollers N at a speed of 3500 rpm. The double helix core yarn passes through the yarn guide O and is twisted and covered by the dispersed fibers in the friction roller N. The covered yarn is held and conveyed by the first yarn guide roller P and the second yarn guide roller Q. Finally, it is wound onto the grooved drum T through the yarn guide hole S on the yarn guide traverse device R to form a double helix core-covered yarn. The linear density of the double helix core-covered yarn is 220 tex.

[0057] Example 2

[0058] The preparation method of a core-spun double-helix internally wrapped composite paper yarn is basically the same as that in Example 1, except that the paper weight in step 1 is adjusted to 20 g / m². 2 .

[0059] Example 3

[0060] The preparation method of a core-spun double-helix internally wrapped composite paper yarn is basically the same as that in Example 1, except that the paper weight in step 1 is adjusted to 40 g / m². 2 .

[0061] Example 4

[0062] The preparation method of a core-spun double-helix internally wrapped composite paper yarn is basically the same as that in Example 1, except that the rotation speed of spindle H during twisting in step 3 is adjusted to 1500 rpm.

[0063] Example 5

[0064] The preparation method of a core-spun double-helix internally wrapped composite paper yarn is basically the same as that in Example 1, except that the rotation speed of spindle H during twisting in step 3 is adjusted to 3500 rpm.

[0065] Comparative Example 1

[0066] A method for preparing a core-spun double-helix internally wrapped composite paper yarn is as follows:

[0067] Step 1: Paper strip preparation: 5 kg of viscose fiber and 60 kg of pulp are selected as raw materials for paper strips. Impurities are removed, and the pulp is bleached and broken up using sodium hypochlorite bleaching agent. Then, 8 kg of calcium carbonate and 1 kg of sizing agent are added, and finally water is added and mixed thoroughly to obtain a pulp with a concentration of 0.2 wt%. The width of the KLM-CX-2 type paper sheet forming machine is adjusted to 50 mm. The wet paper is then pasted onto a drying cylinder, where the heat evaporates the remaining moisture, allowing the paper sheet to dry completely, resulting in a basis weight of 30 g / m². 2 The paper sheets are wound onto the paper tape tube; the paper tape tube is placed on the tension frame of the paper strip cutting machine, and the paper sheets are cut into 2mm wide strips by the cutting roller. The cut paper strips are separated from the cutting roller by the splitting plate and wound into a paper strip roll tube.

[0068] Step 2, Paper strip / filament ring twisting into yarn: The paper strip rolls prepared in Step 1 are placed on the roving spindle A1 of the ring spinning machine (without the drafting system). One paper strip is unwound and fed into the front roller nip F formed by the meshing of the front roller D and the front rubber roller E on the yarn guide C. A viscose filament unwound from the roving spindle B1 is also fed into the front roller nip F via the tension roller C, where it merges with the paper strip. The merged filament and paper strip are output from the roller nip F at a linear speed of 10 m / min. The output viscose filament and paper strip are twisted, wound, and pulled by the spindle H at a rotation speed of 5000 rpm. The twisted paper strip and filament form a composite paper strip, which is finally wound into a packaged paper yarn I.

[0069] Step 3, Preparation of double helix core yarn: Feed one piece of paper yarn prepared in step 2 and one piece of 50D viscose filament into the front roller nip F formed by the meshing of the front roller D and the front rubber roller E of the ring spinning machine, and perform double twisting. The output linear speed is 10 m / min, and the spindle H rotates at 2500 rpm when twisting to form double helix core yarn.

[0070] Step 4, Short Fiber False Twist Covering Yarn: The double helix core yarn prepared in Step 3 is placed on the spindle seat J of the friction spinning machine. Cotton fiber sliver S1 is selected, held by the traction roller K, and fed into the combing roller M through the feed roller L. The speed of the combing roller M is 3500 rpm, which combs and disperses the short fiber sliver S1. The combed short fibers enter between the friction rollers N at a speed of 3500 rpm. The double helix core yarn passes through the yarn guide O and is twisted and covered by the dispersed fibers in the friction roller N. The covered yarn is held and conveyed by the first yarn guide roller P and the second yarn guide roller Q. Finally, it is wound onto the grooved drum T through the yarn guide hole S on the yarn guide traverse device R to form a double helix core-covered yarn. The linear density of the double helix core-covered yarn is 220 tex.

[0071] Comparative Example 2

[0072] A method for preparing a core-spun double-helix internally wrapped composite paper yarn is as follows:

[0073] Step 1: Nonwoven fabric / filament ring spinning and twisting into yarn: The nonwoven fabric strip is placed on the roving spindle A1 of the ring spinning machine without a drafting system. One nonwoven fabric strip is unwound and fed into the front roller nip F formed by the engagement of the front roller D and the front rubber roller E on the yarn guide C. A viscose filament unwound from the roving spindle B1 is also fed into the front roller nip F through the tension roller C and merges with the nonwoven fabric strip. The merged filament and nonwoven fabric strip are output from the roller nip F at a linear speed of 10 m / min. The output viscose filament and nonwoven fabric strip are twisted, wound, and pulled by the spindle H. The spindle rotation speed is 5000 rpm. The twisted nonwoven fabric strip and filament form a composite nonwoven yarn.

[0074] Step 2, Preparation of double helix core yarn: Feed one viscose filament and one nonwoven yarn prepared in step 1 into the front roller nip F formed by the meshing of the front roller D and the front rubber roller E of the ring spinning machine, and perform double twisting. The output linear speed is 10 m / min, and the spindle H rotates at 2500 rpm when twisting to form a double helix core yarn.

[0075] Step 3, Short Fiber False Twist Covering Yarn: The double helix core yarn prepared in Step 2 is placed on the spindle seat J of the friction spinning machine. Cotton fiber sliver S1 is selected, held by the traction roller K, and fed into the combing roller M through the feed roller L. The speed of the combing roller M is 3500 rpm, which combs and disperses the short fiber sliver S1. The combed short fibers enter between the friction rollers N at a speed of 3500 rpm. The double helix core yarn passes through the yarn guide O and is twisted and covered by the dispersed fibers in the friction roller N. The covered yarn is held and conveyed by the first yarn guide roller P and the second yarn guide roller Q. Finally, it is wound onto the grooved drum T through the yarn guide hole S on the yarn guide traverse device R to form a double helix core-covered yarn. The linear density of the double helix core-covered yarn is 220 tex.

[0076] Comparative Example 3

[0077] A method for preparing a core-spun double-helix internally wrapped composite paper yarn is as follows:

[0078] Step 1: Feed two viscose filaments into the front roller nip F formed by the meshing of the front roller D and the front rubber roller E of the ring spinning machine, and perform double twisting. The output linear speed is 10 m / min, and the spindle H rotates at 2500 rpm when twisting to form a double helix yarn.

[0079] Step 2, Short Fiber False Twist Covering Yarn: The double helix yarn prepared in Step 1 is placed on the spindle seat J of a friction spinning machine. Cotton fiber sliver S1 is selected, held by the traction roller K, and fed into the combing roller M via the feed roller L. The speed of the combing roller M is 3500 rpm, which combs and disperses the short fiber sliver S1. The combed short fibers enter between the friction rollers N at a speed of 3500 rpm. The double helix core yarn passes through the yarn guide O and is twisted and covered by the dispersed fibers in the friction roller N. The covered yarn is held and conveyed by the first yarn guide roller P and the second yarn guide roller Q, and finally wound onto the grooved drum T through the yarn guide hole S on the yarn guide traverse device R to form a double helix core-covered yarn. The linear density of the double helix core-covered yarn is 220 tex.

[0080] Comparative Example 4

[0081] A method for preparing pure cotton ring-spun yarn is as follows:

[0082] Two pure cotton ring-spun yarns with a count of 110 tex and a twist of 40 twists / 10 cm are fed into the front roller nip F formed by the meshing of the front roller D and the front rubber roller E of the ring spinning machine. They are then combined and twisted, with an output linear speed of 10 m / min. The spindle H rotates at 2500 rpm during twisting to form a double helix yarn.

[0083] Test Example 1

[0084] Thermal insulation test

[0085] Using 5tex cotton yarn as the warp yarn and the yarn prepared in the examples and comparative examples as the weft yarn, fabric samples were manufactured in plain weave according to the specifications of 100 warp threads / 10cm and 100 weft threads / 10cm, and then tested for heat preservation and air permeability.

[0086] The YG606D flat-plate fabric insulation tester was used to test the examples and comparative examples. The test results are shown in Table 1. The tests were conducted under standard experimental conditions, namely, temperature 23±5℃ and humidity 65±15%RH.

[0087] Table 1

[0088]

[0089]

[0090] Test Example 2

[0091] Breathability test

[0092] The air permeability of the fabric was tested using a YG461E fabric air permeability tester at a pressure of 200 Pa. The test was conducted under standard laboratory conditions: temperature 23±5℃ and humidity 65±15%RH. The test results are shown in Table 2.

[0093] Table 2

[0094] Example 1 710.12 Example 2 735.32 Example 3 755.40 Example 4 735.66 Example 5 795.83 Comparative Example 1 690.17 Comparative Example 2 655.21 Comparative Example 3 621.80 Comparative Example 4 605.73

[0095] The results of Test Example 1 show that Example 1 has the best heat preservation rate, while the results of Test Example 2 show that Example 5 has the best air permeability.

[0096] The optimal heat retention rate in Example 1 is mainly attributed to the precise synergy of structure, materials, and processes, achieved by using 30g / m 2 The paper sheet weight, forming a paper yarn component of moderate volume within the core yarn, utilizes the natural micropores of paper fibers to trap stagnant air while avoiding the loose pores caused by excessively low weight or the core yarn exposure caused by excessively high weight, ensuring uniform and sealed pore distribution. Simultaneously, the 2500rpm twist design tightly integrates the paper yarn and nonwoven yarn, forming a stable double-helix structure. This reduces air convection heat loss through the helical gaps and avoids the loose yarn and disordered pores caused by low twist or the excessive pore compression caused by high twist, achieving a precise balance between pore size and distribution. Furthermore, the introduction of nonwoven yarn utilizes the three-dimensional fluffy network of nonwoven fibers to increase pore tortuosity and prolong air retention time. The friction-spun outer layer of cotton fibers evenly covers the core yarn surface, preventing core yarn exposure. Combined with the insulation effect of cotton fibers, this forms a triple insulation mechanism of micropore heat retention, helical stabilization, and outer insulation, significantly superior to the single-material structure of pure filament or pure cotton yarn.

[0097] Example 5 exhibited the highest air permeability, primarily attributed to its high twist design and optimized paper weight. Compared to Example 1, the high twist of Example 5 resulted in a tighter integration of the paper yarn and nonwoven yarn, forming a denser double-helix structure. This significantly reduced inter-fiber frictional resistance and optimized pore continuity, creating more efficient airflow channels. In the comparative examples, Example 1 demonstrated superior air permeability compared to Comparative Examples 1 and 2. This was mainly due to its composite structure design; the combination of paper yarn and nonwoven yarn created a gradient pore distribution, significantly superior to the dense structure of a single material, thus improving air permeability. Comparative Examples 3 and 4, lacking the composite design of paper yarn and nonwoven yarn, relied solely on viscose filaments or pure cotton yarn to construct the yarn, failing to form effective air-permeable pores, leading to further reduced air permeability. Therefore, Example 5, through its high twist design and optimized paper weight, constructed efficient airflow channels, significantly improving air permeability.

Claims

1. A method for preparing a core-spun double-helix internally wrapped composite paper yarn, characterized in that, The method is as follows: Step 1, Paper strip preparation: Select ultra-short fiber and pulp as raw materials for paper strips. Remove impurities, bleach with sodium hypochlorite, and break down the pulp. Then add calcium carbonate, sizing agent, and finally add water and mix evenly to obtain a pulp material with a pulp concentration of 0.1-2wt%. Adjust the width of the paper sheet forming device, and then place the pulp material on the drying cylinder. Use heat to evaporate the remaining moisture and make the paper sheet completely dry. The obtained paper sheet is then wound onto a paper tape roll. The paper sheet is cut into strips by a cutting roller and wound into a paper strip roll. Step 2: Paper strip / filament and nonwoven fabric / filament ring twisting into yarn: The paper strip rolls prepared in Step 1 are placed on the roving spindles of a ring spinning machine without a drafting system. 1-100 paper strips are unwound and fed into the front roller nip (F) formed by the meshing of the front roller (D) and front rubber roller (E) of the ring spinning machine via the tension wheel (C) on the yarn guide. 1-100 filaments unwound from the roving spindle... The filaments, also fed into the front roller nip (F) via the tension wheel (C), merge with the paper strip. The merged filaments and paper strip are output from the roller nip (F). The output filaments and paper strip are twisted, wound, and pulled by the spindle (H). The twisted paper strip and filaments form a composite paper strip, which is finally wound into a tube of paper yarn (I). The composite twisting of viscose nonwoven fabric and filaments is carried out using the same process as that of paper strips and filaments to prepare nonwoven yarn. Step 3, Preparation of double helix core yarn: Feed 1-100 pieces of paper yarn prepared in step 2 and 1-100 pieces of nonwoven fabric yarn prepared in step 2 into the front roller nip (F) formed by the meshing of the front roller (D) and the front rubber roller (E) of the ring spinning machine, and perform doubling twisting. The output linear speed is 3-25 m / min, and the spindle (H) rotation speed is 1500-3500 rpm when twisting to form double helix core yarn; Step 4, Short Fiber False Twist Covering Yarn: Place the double helix core yarn prepared in Step 3 on the spindle seat (J) of the friction spinning machine, select cotton fiber sliver (S1), hold it with the traction roller (K), and feed it into the combing roller (M) through the feed roller (L) to comb and disperse the cotton fiber sliver (S1). The combed short fibers enter between the friction rollers (N). The double helix core yarn passes through the yarn guide (O) and is twisted and covered by the loose fibers in the friction roller (N). The covered yarn is held and conveyed by the first yarn guide roller (P) and the second yarn guide roller (Q), and finally wound on the grooved drum (T) through the yarn guide hole (S) on the yarn guide traverse device (R) to form a double helix core-covered yarn. The paper weight in step 1 is 10-200 g / m³. 2 ; In step 1, the length of the ultrashort fiber is 1-10 mm.

2. The preparation method of the core-spun double-helix internally wrapped composite paper yarn as described in claim 1, characterized in that, In step 1, the paper is cut into strips with a width of 1-10mm by a cutting roller.

3. The preparation method of the core-spun double-helix internally wrapped composite paper yarn as described in claim 1, characterized in that, In step 1, the short fibers are at least one of the following: silver ion fibers, bamboo fibers, chitosan fibers, carbon fibers, stainless steel fibers, polyaniline fibers, polypyrrole fibers, graphene fibers, aramid fibers, polyimide fibers, glass fibers, basalt fibers, cotton fibers, hemp fibers, wool fibers, silk short fibers, viscose fibers, cuprammonium fibers, acetate fibers, polyester fibers, nylon fibers, polypropylene fibers, acrylic fibers, spandex fibers, polylactic acid fibers, and recycled textile fibers.

4. The method for preparing the core-spun double-helix internally wrapped composite paper yarn as described in claim 1, characterized in that, In step 2, the filament is at least one of viscose filament, polyethylene filament, basalt filament, polyester filament, nylon filament, spandex filament, polypropylene filament, acrylic filament, polyimide filament, and water-soluble vinylon filament.

5. The method for preparing the core-spun double-helix internally wrapped composite paper yarn as described in claim 1, characterized in that, In step 2, the output linear speed is controlled at 3-25 m / min; the spindle rotation speed is 1000-8000 rpm during twisting.

6. The method for preparing the core-spun double-helix internally wrapped composite paper yarn as described in claim 1, characterized in that, In step 4, the linear density of the double-helix core-spun yarn is above 25 tex.

7. The method for preparing the core-spun double-helix internally wrapped composite paper yarn as described in claim 1, characterized in that, In step 4, the speed of the combing roller (M) is 500-5000 rpm, and the combed short fibers enter between the friction rollers (N) with a speed of 500-5000 rpm.

8. A core-spun double-helix internally wrapped composite paper yarn, characterized in that, It is prepared by the preparation method described in any one of claims 1 to 7.

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