Special-shaped polyphenylene sulfide short fiber blended yarn for hydrogen production diaphragm and spinning method of special-shaped polyphenylene sulfide short fiber blended yarn

Abstract

The invention is suitable for the technical field of spinning, and provides a special-shaped polyphenylene sulfide short fiber blended yarn for a hydrogen production diaphragm, the British system count of the blended yarn is 5-20S, and the blended yarn is made of polyphenylene sulfide short fibers with different special-shaped sections. The invention further provides a spinning method of the special-shaped polyphenylene sulfide short fiber blended yarn for the hydrogen production diaphragm. The spinning method comprises the steps of curing, blowing, carding, drawing, roving, spinning and spooling. The polyphenylene sulfide short fibers with different section shapes are subjected to mixed spinning, the specific surface area of the fibers is increased through the special-shaped fibers, the porosity is increased from the yarn end due to the fact that the shapes of the special-shaped section fibers are different, more small pores exist between the fibers in the yarn, meanwhile, the yarn body is more fluffy due to the low twist, the porosity is further increased, and therefore the specific surface area of the fibers is increased. The prepared yarn has the characteristics of good evenness, less hairiness, low twist and fluffiness, higher yield and the like, and the diaphragm prepared from the yarn has high efficiency of hydrogen production by alkaline water electrolysis.

Description

Technical Field

[0001] The invention belongs to the technical field of spinning, and in particular relates to a special-shaped polyphenylene sulfide staple fiber blended yarn for a hydrogen production diaphragm and a spinning method thereof. Background Art

[0002] Hydrogen energy is a secondary energy source with abundant sources, green and low carbon, and wide application. It has the advantages of high energy density, abundant reserves, and zero pollution. The current mainstream electrolysis technologies include alkaline aqueous solution electrolysis technology (ALE technology), proton exchange membrane water electrolysis technology (PEM technology), solid oxide water electrolysis technology (SOFC technology), and anion exchange membrane technology (AEM technology). Among them, only alkaline aqueous solution electrolysis is suitable for large-scale hydrogen production. Alkaline aqueous solution electrolysis hydrogen production technology is a mature and widely used technology with high efficiency and low cost. The main materials used include diaphragms, metal alloy electrodes, and KOH electrolytes. The principle is to use alkaline water electrolysis cells to produce H2 at the cathode and O2 at the anode by electrolyzing water. In this process, the two gases need to be separated, otherwise H2 and O2 will mix, which will not only fail to achieve the purpose of producing H2, but also bring safety hazards. The diaphragm is the key material to separate H2 and O2, so the quality of the diaphragm is directly related to the purity and power consumption of H2 and O2. The requirements for the diaphragm are to ensure that hydrogen and oxygen molecules cannot pass through the diaphragm, but allow electrolyte ions to pass through. It must also be resistant to corrosion by high-concentration alkali solutions, have good mechanical strength, have the highest possible porosity, be chemically stable under electrolysis temperature and alkali conditions, have readily available raw materials, be non-toxic and pollution-free, and have easy waste disposal.

[0003] PPS (polyphenylene sulfide) diaphragm, also known as fabric diaphragm, is a diaphragm cloth made of polyphenylene sulfide short fibers through weaving, spunlace and other processes. It can maintain stable performance under alkaline and high temperature conditions. Therefore, it is widely used to prepare alkaline hydrogen production diaphragms and is also the mainstream diaphragm for alkaline water electrolysis hydrogen production. Existing PPS (polyphenylene sulfide) diaphragms are generally spun from a type of polyphenylene sulfide short fibers. The fabric thickness is usually more than 700 microns, and the diaphragm porosity is low, which not only makes it difficult for gas to pass through, affecting the efficiency of hydrogen production, but also increases the electricity cost of alkaline water electrolysis hydrogen production. Summary of the invention

[0004] The purpose of the embodiment of the present invention is to provide a shaped polyphenylene sulfide staple fiber blended yarn for a hydrogen production diaphragm, aiming to solve the problems existing in the above-mentioned background technology.

[0005] The embodiment of the present invention is implemented as follows: a shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production diaphragm, the blended yarn has an English count of 5-20S, and is made of polyphenylene sulfide staple fibers with different shaped cross-sections.

[0006] Preferably, the polyphenylene sulfide staple fibers with special-shaped cross-sections are selected from circular polyphenylene sulfide staple fibers, triangular polyphenylene sulfide staple fibers, cross polyphenylene sulfide staple fibers, hollow polyphenylene sulfide staple fibers, Y-shaped polyphenylene sulfide staple fibers, and clover-shaped polyphenylene sulfide staple fibers.

[0007] Another object of an embodiment of the present invention is to provide a spinning method for special-shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane, including the steps of curing, cleaning, carding, drawing, roving, spun spinning and winding.

[0008] Preferably, the curing step is specifically as follows: mixing polyphenylene sulfide staple fibers with different shaped cross-sections, then evenly mixing water, an antistatic agent, and crude oil, and then atomizing and spraying the mixture on the polyphenylene sulfide staple fibers, and then placing the polyphenylene sulfide staple fibers in an environment with a temperature of 25-30° C. and a humidity of 55%-65% for 24 hours to obtain mixed fibers, wherein the mass ratio of the polyphenylene sulfide staple fibers to water, the antistatic agent, and the crude oil is 1:0.1:0.03:0.02.

[0009] Preferably, the steps of the cotton cleaning process are specifically as follows: the mixed fibers are passed through a disc plucking machine, a multi-bin cotton mixing machine, a vertical baling machine, a disc plucking machine, a multi-bin cotton mixing machine, a combing needle cotton opening machine, a vibrating cotton box cotton feeding machine, a single-beater lap machine, and a cotton combing machine to obtain a mixed raw material.

[0010] Preferably, the steps of the combing process are as follows: combing the mixed raw materials mainly and mixing them as a supplement, using a moderate combing distance, increasing the rotation speed of the cylinder and doffer, increasing the sliver quantity, and reducing the sliver output speed to obtain mixed sliver.

[0011] Preferably, the steps of the drawing process and the roving process are as follows: the mixed raw sliver is made into ready sliver by three-pass drawing and then made into roving, the ambient humidity of the drawing process is 65%-70%, and the twist of the roving process is controlled to be 10% larger.

[0012] Preferably, the steps of the spinning process and the winding process are specifically as follows: the spinning process is equipped with a Siro compact spinning device, the roving is spun into a cop yarn through a Siro compact spinning process, and then made into a cone yarn, and the twist of the spinning process is controlled to be 10%-20% smaller.

[0013] An embodiment of the present invention provides a shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production diaphragm. Polyphenylene sulfide staple fibers of different cross-sectional shapes are mixed and spun. The shaped fibers increase the specific surface area of ​​the fibers. The different shapes of the shaped cross-sectional fibers are used to create more small pores between the fibers in the yarn, thereby increasing the porosity from the yarn end. At the same time, the lower twist makes the yarn body more fluffy, further increasing the porosity. The yarn made from the embodiment of the present invention has the characteristics of good evenness, less hairiness, low twist and fluffiness, and higher yield. The diaphragm made from the yarn has the characteristics of high air tightness, strong ion permeability, high porosity, and small pores. The efficiency of hydrogen production by alkaline water electrolysis is high, which can be increased from 60%-70% to 65%-75%, thereby helping alkaline water electrolysis hydrogen production enterprises to reduce costs and increase efficiency and rapidly promote the hydrogen energy industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of polyphenylene sulfide staple fibers with different profiled cross sections provided by an embodiment of the present invention;

[0015] Figure 2 A schematic diagram of mixed polyphenylene sulfide staple fibers with different profiled cross-sections provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] A special-shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production diaphragm, the spinning method of which comprises the following steps:

[0018] (1) Curing: The polyphenylene sulfide staple fibers with different profiled cross sections are mixed and cured. The specific curing process is to evenly mix 10% water with 3.0% antistatic agent and 2.0% crude oil of equal short fiber mass fraction, and then spray the mixture on the polyphenylene sulfide staple fibers through an atomizer, and place the mixture in a crude oil bin at a temperature of 25-30°C and a humidity of 55%-65% for 24 hours to improve the spinnability of the polyphenylene sulfide staple fibers and obtain mixed fibers;

[0019] (2) Blowing process: The cured mixed fiber is passed through a disc plucker → FA022-6 multi-bin blender → vertical baler → disc plucker → multi-bin blender → combing needle opener → vibrating cotton box feeder → FA141A single beater lap machine → combing machine. The cured polyphenylene sulfide staple fiber is pre-mixed by beating it into soft bags, increasing the speed of the plucker beater and combing needle beater, improving the fiber mixing degree, and making the fibers with different cross sections evenly distributed.

[0020] (3) Combing process: The combing process is mainly based on combing and supplemented by mixing. It follows the process principle of "medium spacing, large quantity, and slow speed". It adopts a moderate combing spacing, appropriately increases the speed of the cylinder and doffer, increases the quantity of the carded sliver, and reduces the speed of the carded sliver to obtain mixed carded sliver.

[0021] (4) Drawing process: The drawing process adopts three steps of drawing. Compared with the spinning of ordinary round polyphenylene sulfide staple fibers, the special-shaped cross-section polyphenylene sulfide staple fibers have a larger fiber specific surface area and a larger friction coefficient, which is more likely to generate static electricity. In the carding process, it is easy to entangle the light rollers, and in the drawing process, entanglement and sticking to the leather rollers appear. In addition to health treatment of the raw materials, it is also necessary to do a good job of moisturizing the production process, and in the drawing process, the rollers and rubber rollers need to be treated with antistatic treatment. At the same time, the environmental humidity should be increased and controlled at 65%-70%;

[0022] (5) Roving process: The twist of the roving process is controlled to be about 10% larger, and the roving is wound around the duck's foot three times;

[0023] (6) Spinning process: The spinning process is equipped with a siro compact spinning device, and the negative pressure is increased by 15% compared with that of ordinary polyphenylene sulfide yarn. The spinning drafting gauge adopts the improved medium and long fiber suitable gauge. Under the condition of ensuring less broken ends, the weighted and high-arched steel wire ring is used as much as possible, and the speed is appropriately reduced. Due to the use of polyphenylene sulfide short fibers with different special-shaped cross-sections, the lateral force between the fibers in the yarn body is large, the yarn can withstand a large tension, and it is not easy to break. Therefore, the twist is controlled by 10%-20% lower than that of ordinary polyphenylene sulfide yarn, making the yarn body more fluffy and also increasing the output;

[0024] (7) Winding process: It is mainly used to ensure that the yarn channel is smooth, avoid scratching, and reduce the generation of hairiness.

[0025] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0026] Embodiment 1: A shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane, wherein the spinning method comprises the following steps:

[0027] (1) Siro compact-spun polyphenylene sulfide yarn, with a yarn count of 20 Ne, and the polyphenylene sulfide staple fibers used are as follows (proportions by mass): 10% hollow polyphenylene sulfide staple fibers, 20% cross polyphenylene sulfide staple fibers, 30% triangular polyphenylene sulfide staple fibers, and 40% round polyphenylene sulfide staple fibers;

[0028] (2) The process flow is:

[0029]

[0030] (3) Process of each process:

[0031] Blowing and cleaning: The equipment configuration is FA002A disc plucker → FA022-6 multi-bin blender → ZF1102A needle opener → FA046A vibrating cotton box feeder → FA141A single beater lap machine; the main process parameters are: ZFA1102A needle beater speed 600rpm, roller and needle beater spacing 12mm, comprehensive beater speed 700rpm, roll weight 380g / m, roll length 32m;

[0032] Carding: FA201B carding machine is used, and the main process parameters are: sliver weight 25g / 5m, sliver delivery speed 60m / min, cylinder speed 330rpm, licker-in speed 654rpm, flat board speed 195mm / min, cylinder and flat board spacing 10 / 9 / 9 / 9 / 10 (1inch‰);

[0033] Drawing: The drawing process adopts three draws, and the number of draws is six. The equipment is JWF1310 drawing frame (one draw) → JWF1310 drawing frame (two draws) → RSB-D22C drawing frame (final draw). The main process parameters are: one draw weight is 25g / 5m, total draft is 6.0 times, rear draft is 1.75 times, roller gauge (front zone × rear zone) is 16×30mm, and the delivery speed is 3 50m / min; second doubling weight is 25g / 5m, total draft 6.0 times, back zone draft 1.5 times, roller gauge (front zone × back zone) 16×30mm, sliver delivery speed 300m / min; final doubling number is 6, weight 25g / 5m, total draft 6.0 times, back zone draft 1.3 times, roller gauge (front zone × back zone) 17.5×27mm, sliver delivery speed 300m / min;

[0034] Roving: The roving process is produced by FA497 roving machine, and the main process parameters are: roving weight 7.0g / 10m, twist 2.5 twist / 10cm, total draft 7.1 times, rear draft 1.19 times, roller gauge (front

[0035] × middle × rear) 13 × 36 × 42mm, jaw spacing block 7mm, spindle speed 750rpm;

[0036] Spinning: The spinning process is produced on a JWF1510 four-roller Siro compact spinning machine. The twist is controlled to be low, the negative pressure is increased, and the wire ring is used heavily. The main process parameters are: yarn count 20Ne, total drafting multiple 51 times, rear zone drafting multiple 1.212 times, jaw spacing block 5.0mm, twist 26 twists / 10cm, roller spacing (front×rear) 20×40mm, special-shaped tube negative pressure about 50mbar, spindle speed 12500rpm;

[0037] Winding: SAVIO PolarL automatic winder is used for production, the winding speed is 600m / min, and the electronic yarn clearer channel settings are: N: 5.8, DS×LS: 3.4×3.5, DL×LL: 1.5×28, -D×-L: -20%×18.

[0038] The blended yarn obtained by spinning in Example 1 was made into a diaphragm according to the prior art and compared with a common PPS short fiber diaphragm, and the relevant performance data were obtained as shown in Table 1:

[0039] Table 1

[0040]

[0041] Embodiment 2: A shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane, wherein the spinning method comprises the following steps:

[0042] (1) Siro compact-spun polyphenylene sulfide yarn, the yarn count is 14Ne, and the polyphenylene sulfide staple fibers used are as follows (proportions are based on mass ratio): 30% round polyphenylene sulfide staple fibers, 30% cross polyphenylene sulfide staple fibers, and 40% cloverleaf polyphenylene sulfide staple fibers;

[0043] (2) The process flow is:

[0044]

[0045] (3) Process of each process:

[0046] Blow-drying: The equipment configuration is FA002A disc plucker → FA022-6 multi-bin cotton mixer → ZF1102A needle opener → FA046A vibrating cotton box feeder; the main process parameters are: ZFA1102A needle beater speed 650rpm, roller and needle beater spacing 11mm, comprehensive beater speed 700rpm, roll basis weight 380g / m, roll length 32m;

[0047] Carding: FA201B carding machine is used, and the main process parameters are: FA201B carding machine is used, and the main process parameters are: sliver weight 30g / 5m, sliver delivery speed 60m / min, cylinder speed 330rpm, licker-in roller speed 654rpm, flat plate speed 195mm / min, cylinder and flat plate spacing 9 / 8 / 8 / 8 / 9 (1inch‰);

[0048] Drawing: The drawing process adopts three draws and the number of draws is six. The equipment is JWF1310 drawing frame (one draw) → JWF1310 drawing frame (two draws) → RSB-D22C drawing frame (final draw). The main process parameters are: one draw weight is 26g / 5m, total draft is 6.93 times, rear draft is 1.75 times, roller gauge (front zone × rear zone) is 16×30mm, and the delivery speed is 35 0m / min, two-fold quantitative 26g / 5m, total draft 6.0 times, rear zone draft 1.75 times, roller gauge (front zone × rear zone) 16×30mm, strip speed 350m / min, final doubling number 6, quantitative 26g / 5m, total draft 5.98 times, rear zone draft 1.3 times, roller gauge (front zone × rear zone) 18.5×27mm, strip speed 300m / min;

[0049] Roving: The roving process is produced by FA497 roving machine, and the main process parameters are: roving weight 7.5g / 10m, twist 2.7 twist / 10cm, total draft 6.93 times, rear draft 1.19 times, roller gauge (front

[0050] × middle × rear) 13 × 36 × 42mm, jaw spacing block 7mm, spindle speed 700rpm;

[0051] Spinning: The spinning process is produced on a JWF1510 four-roller Siro compact spinning machine. The twist is controlled to be low, the negative pressure is increased, and the wire ring is used heavily. The main process parameters are: yarn count in British system is 14Ne, the total drafting multiple is 38.2 times, the back zone drafting multiple is 1.136 times, the jaw spacing block is 5.0mm, the twist is 25 twists / 10cm, the roller spacing (front×back) is 20×40mm, the negative pressure of the special-shaped tube is about 55mbar, and the spindle speed is 8500rpm;

[0052] Winding: SAVIO PolarL automatic winder is used for production, the winding speed is 600m / min, and the electronic yarn clearer channel settings are: N: 6.0, DS×LS: 3.5×3.6, DL×LL: 1.5×28, -D×-L: -22%×20.

[0053] The blended yarn obtained by spinning in Example 2 was made into a diaphragm according to the prior art, and compared with the ordinary PPS short fiber diaphragm, the relevant performance data were obtained as shown in Table 2:

[0054] Table 2

[0055]

[0056] Embodiment 3: A shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane, wherein the spinning method comprises the following steps:

[0057] (1) Siro compact-spun polyphenylene sulfide yarn, the yarn count is 8Ne, and the polyphenylene sulfide staple fibers used are as follows (proportions are based on mass ratio): 50% round polyphenylene sulfide staple fibers, 35% Y-shaped polyphenylene sulfide staple fibers, and 15% hollow polyphenylene sulfide staple fibers;

[0058] (2) The process flow is as follows:

[0059]

[0060] (3) Process of each process:

[0061] Blow-drying: The equipment configuration is FA002A disc plucker → FA022-6 multi-bin cotton mixer → ZF1102A needle opener → FA046A vibrating cotton box feeder; the main process parameters are: ZFA1102A needle beater speed 650rpm, roller and needle beater spacing 11mm, comprehensive beater speed 700rpm, roll basis weight 380g / m, roll length 32m;

[0062] Carding: FA201B carding machine is used, and the main process parameters are: sliver weight 30g / 5m, sliver delivery speed 60m / min, cylinder speed 300rpm, licker-in speed 564rpm, flat plate speed 195mm / min, cylinder and flat plate spacing 10 / 9 / 9 / 9 / 10 (unit × 1inch‰);

[0063] Drawing: The drawing process adopts three draws and the number of draws is six. The equipment is JWF1310 drawing frame (one draw) → JWF1310 drawing frame (two draws) → RSB-D22C drawing frame (final draw). The main process parameters are: one draw weight is 26g / 5m, total draft is 6.93 times, rear draft is 1.75 times, roller gauge (front zone × rear zone) is 16×30mm, and the delivery speed is 35 0m / min, two-fold quantitative 26g / 5m, total draft 6.0 times, rear zone draft 1.75 times, roller gauge (front zone × rear zone) 16×30mm, strip speed 350m / min, final doubling number 6, quantitative 26g / 5m, total draft 5.98 times, rear zone draft 1.3 times, roller gauge (front zone × rear zone) 18.5×27mm, strip speed 300m / min;

[0064] Roving: The roving process is produced by FA497 roving machine, and the main process parameters are: roving weight 9.0g / 10m, twist 2.0 twist / 10cm, total draft 5.78 times, rear draft 1.19 times, roller gauge (front

[0065] × middle × rear) 13 × 36 × 42mm, jaw spacing block 8mm, spindle speed 600rpm;

[0066] Spinning: The spinning process is produced on a JWF1510 four-roller Siro compact spinning machine. The twist is controlled to be low, the negative pressure is increased, and the wire ring is used heavily. The main process parameters are: yarn count in British system is 8Ne, the total drafting multiple is 26.2 times, the back zone drafting multiple is 1.136 times, the jaw spacing block is 6.0mm, the twist is 23 twists / 10cm, the roller spacing (front×back) is 20×40mm, the negative pressure of the special-shaped tube is about 65mbar, and the spindle speed is 7500rpm;

[0067] Winding: SAVIO PolarL automatic winder is used for production, the winding speed is 600m / min, and the electronic yarn clearer channel settings are: N: 6.5, DS×LS: 3.6×3.7, DL×LL: 1.6×30, -D×-L: -22%×20.

[0068] The blended yarn obtained by spinning in Example 3 was made into a diaphragm according to the prior art, and compared with the ordinary PPS short fiber diaphragm, the relevant performance data were obtained as shown in Table 3:

[0069] Table 3

[0070]

[0071] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production diaphragm, characterized in that: The blended yarn has an imperial count of 5-20S and is made of polyphenylene sulfide staple fibers with different profiled cross sections.

2. The shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane according to claim 1, characterized in that: The polyphenylene sulfide staple fibers with special cross-sections are selected from circular polyphenylene sulfide staple fibers, triangular polyphenylene sulfide staple fibers, cross polyphenylene sulfide staple fibers, hollow polyphenylene sulfide staple fibers, Y-shaped polyphenylene sulfide staple fibers, and clover-shaped polyphenylene sulfide staple fibers.

3. A spinning method for the shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane according to claim 1 or 2, characterized in that: The process includes health care, cotton cleaning, carding, drawing, roving, spun spinning and winding.

4. The spinning method of the special-shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane according to claim 3, characterized in that: The curing steps are specifically as follows: mixing polyphenylene sulfide staple fibers with different shaped cross-sections, then evenly mixing water, an antistatic agent, and crude oil, and then atomizing and spraying the mixture on the polyphenylene sulfide staple fibers, and then placing the polyphenylene sulfide staple fibers in an environment with a temperature of 25-30° C. and a humidity of 55%-65% for 24 hours to obtain mixed fibers, wherein the mass ratio of the polyphenylene sulfide staple fibers to water, the antistatic agent, and the crude oil is 1:0.1:0.03:0.

02.

5. The spinning method of the special-shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane according to claim 4, characterized in that: The steps of the cotton cleaning process are specifically as follows: the mixed fiber is passed through a disc plucking machine, a multi-bin cotton mixing machine, a vertical baling machine, a disc plucking machine, a multi-bin cotton mixing machine, a combing needle cotton opening machine, a vibrating cotton box cotton feeding machine, a single beater lap machine, and a cotton combing machine to obtain a mixed raw material.

6. The spinning method of the special-shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane according to claim 5, characterized in that: The steps of the combing process are as follows: combing the mixed raw materials mainly and mixing them as a supplement, using a moderate combing distance, increasing the rotation speed of the cylinder and the doffer, increasing the sliver quantity, and reducing the sliver output speed to obtain mixed sliver.

7. The spinning method of the special-shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane according to claim 6, characterized in that: The steps of the drawing process and the roving process are specifically as follows: the mixed raw sliver is made into ready sliver by three-pass drawing and then made into roving, the ambient humidity of the drawing process is 65%-70%, and the twist of the roving process is controlled to be 10% larger.

8. The spinning method of the special-shaped polyphenylene sulfide staple fiber blended yarn for hydrogen production membrane according to claim 7, characterized in that: The steps of the spinning process and the winding process are specifically as follows: the spinning process is equipped with a Siro compact spinning device, the roving is spun into a cop yarn through a Siro compact spinning process, and then made into a cone yarn, and the twist degree of the spinning process is controlled to be 10%-20% smaller.

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