Preparation process of a special sewing thread for automobiles

Abstract

A preparation process of a special sewing thread for automobiles includes the following steps: S1 Weaving: feeding polyester fibers into a weaving machine for weaving to obtain a woven reinforcement thread; S2 Coloring: successively feeding the above-mentioned woven reinforcement thread into a pigment solution tank, a first drying chamber, and a color fixing chamber for coloring, drying, and color fixing; S3 Pretreatment: feeding the colored woven reinforcement thread into a corona treatment chamber first, and performing corona discharge treatment for 30 - 60 s under vacuum conditions; then feeding it into a glue treatment chamber and immersing it in a treatment glue solution for 15 - 45 s; then passing it through a pressure roller for pressure application and feeding it into a second drying chamber for drying; S4 Coating; S5 Thread winding and oiling. The preparation process of the special sewing thread for automobiles according to the present invention uses polyester fibers as raw materials, and through the processes of weaving, coloring, pretreatment, coating, and thread winding and oiling, compared with ordinary polyester-made sewing threads for automobiles, it has more excellent thermal stability performance, mechanical properties, and wear resistance, meets the requirements of automobile applications, and has a wide application prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of textiles, and particularly relates to a preparation process for special sewing threads for automobiles. Background Art

[0002] In recent years, with the rapid development of China's automobile industry, automobile textiles and their fiber materials have also developed accordingly. According to statistics, automobile textiles include airbags, roofs, carpets, seat fabrics, luggage compartment linings, backings, trim panels, filter materials, and awning fabrics, etc. During production, sewing threads are required for automobile textiles. After the fabric raw materials of automobile textiles are cut, they are made into finished products with sewing threads.

[0003] Therefore, as an important auxiliary material, when the sewing thread is applied to automobile textiles, certain requirements are imposed on the performance and post-treatment process of the sewing thread. For example, when the sewing thread is used for the airbag of an automobile, the raw materials of the airbag mainly consist of bag fabric and sewing thread. The raw materials used for the airbag must be able to absorb huge amounts of thermal energy and mechanical energy, and be able to withstand great mechanical stress under extremely harsh temperature conditions, requiring it to be more reliable, more durable, and not easily damaged. Therefore, it is required that the sewing thread for automobiles has excellent physical and chemical properties to meet these stringent requirements.

[0004] Currently, the treatment processes for sewing threads for automobiles mainly include coating adhesion treatment, lubrication treatment, dyeing treatment, etc. Polyester is a widely used sewing thread material at present, and its main advantages include high strength, high heat resistance, high durability, low water absorption, etc. In order to further improve the performance of special sewing threads for automobiles made of polyester, coating treatment is usually carried out on it. Since the molecular structure of polyester is symmetric, with high orientation and crystallinity, and the molecular chain is rigid and lacks highly polar groups, it has significant hydrophobicity and chemical inertness, which brings difficulties to coating.

[0005] Therefore, the purpose of the present invention is to provide a preparation process for special sewing threads for automobiles. Using polyester fibers as raw materials, through processes such as knitting, coloring, pretreatment, coating, and winding and oiling, compared with ordinary sewing threads for automobiles made of polyester, it has more excellent thermal stability performance, mechanical properties, and wear resistance. Summary of the Invention

[0006] Object of the Invention: To overcome the above deficiencies, the object of the present invention is to provide a preparation process for special sewing threads for automobiles. The process is simple. Using polyester fibers as raw materials, through processes such as knitting, coloring, pretreatment, coating, and winding and oiling, compared with ordinary sewing threads for automobiles made of polyester, it has more excellent thermal stability performance, mechanical properties, and wear resistance, and has a wide application prospect.

[0007] The object of the present invention is achieved through the following technical solutions:

[0008] A preparation process for special sewing thread for automobiles, comprising the following steps:

[0009] S1 weaving: feeding the polyester fiber into a weaving machine for weaving to obtain a weaving reinforcement line;

[0010] S2 coloring: sending the braided reinforcement line to the pigment solution tank, drying chamber 1, and color fixing chamber in sequence for coloring, drying, and color fixing; the pigment solution tank contains pigment solution, and the conveying speed of the braided reinforcement line is 10-50m / min;

[0011] S3 pretreatment: the colored braided reinforcement wire is first sent to the corona treatment chamber for corona discharge treatment under vacuum conditions for 30-60 seconds; then sent to the glue treatment chamber and immersed in the treated glue solution for 15-45 seconds; then sent to the drying chamber 2 for drying after being squeezed by the squeezing roller;

[0012] S4 coating: the pretreated braided reinforcing wire is sequentially sent to the resin solution tank and the drying chamber 3 for coating and drying to obtain a semi-finished automobile special sewing wire; the resin solution tank contains a resin solution, and the conveying speed of the braided reinforcing wire is 10-50m / min;

[0013] S5: winding the semi-finished special automotive sewing thread with silicone oil, and then packaging to obtain the finished special automotive sewing thread.

[0014] The present application uses polyester fiber as the raw material of the special sewing thread for automobiles and braids the polyester fiber. Compared with ordinary polyester yarn, the braided reinforcing thread with a braided structure after being braided by a braiding machine has better uniformity, stability and wear resistance when used. The braided reinforcing thread is dyed, dried and fixed to meet the color requirements of the special sewing thread for automobiles.

[0015] In order to further improve the thermal stability, mechanical properties and wear resistance of the braided reinforcement wire, the braided reinforcement wire is further coated. Since polyester molecules have the characteristics of structural symmetry, high orientation and crystallinity, high molecular chain rigidity and lack of high polar groups, they have significant hydrophobicity and chemical inertness, which brings difficulties to coating.

[0016] Therefore, before coating treatment, the present invention first pre-treats the braided reinforcement wire, and the pre-treatment adopts corona discharge + glue treatment. First, corona discharge is used to effectively improve the surface performance of the braided reinforcement wire, and free groups are introduced to improve surface activity, thereby improving the affinity and bonding strength of the subsequent treatment glue and resin solution to the braided reinforcement wire. Then, the braided reinforcement wire is subjected to glue treatment, and polar groups are introduced to enhance the interface bonding between the resin solution and the braided reinforcement wire. The two treatment methods cooperate with each other to make the bonding between the braided reinforcement wire and the resin solution more firmly.

[0017] Further, in the above preparation process of the special sewing thread for automobiles, in S1, the knitting number / strand of the knitting machine is set to 12 outer + 4 core, the knitting pitch is set to 2 - 4 mm, the diameter of the knitting reinforcement thread is 0.6 - 1.2 mm, the breaking strength is 200 - 300 N, and the breaking elongation is 20 - 30%.

[0018] The settings of parameters such as the knitting number / strand and the knitting pitch will affect the physical properties and usage effects of the knitting reinforcement thread. The present invention adopts a knitting number / strand setting of 12 outer + 4 core and a knitting pitch set to 2 - 4 mm, which can make the density of the knitting reinforcement thread moderate, neither too loose to affect the strength nor too tight to cause poor air permeability, improving the strength and wear resistance of the knitting reinforcement thread.

[0019] Further, in the above preparation process of the special sewing thread for automobiles, the pigment solution includes acetone and pigment, and the mass ratio of acetone to pigment is 10 - 30:1; the first drying chamber is dried by steam heating, and the temperature is set to 100 - 130 °C; the color fixing chamber is color fixed by ultraviolet irradiation, and the ultraviolet power is set to 100 - 300 W.

[0020] Further, in the above preparation process of the special sewing thread for automobiles, the voltage of the corona discharge treatment is 1.5 - 3 kV, the frequency is 40 - 60 Hz, and the gas flow rate is 0.8 - 1.2 L / min; the treatment glue solution uses an aqueous PU solution with a mass fraction of 1 - 10%; the second drying chamber is dried by pressurized heating, the pressure is set to 4 - 7 N, and the temperature is set to 100 - 130 °C.

[0021] The treatment glue solution uses an aqueous PU solution. PU has a solubility parameter similar to that of polyester, and polar groups are introduced to enhance the interfacial bonding between the subsequent resin solution and the knitting reinforcement thread. The treatment glue solution and the knitting reinforcement thread are better combined by means of pressurized heating.

[0022] Further, in the above preparation process of the special sewing thread for automobiles, the resin solution includes the following raw materials in parts by weight: 80 - 90 parts of methanol, 5 - 10 parts of Amilan CM4000, 2 - 5 parts of SDBS, 1 - 3 parts of nano-aluminum oxide, 1 - 3 parts of polyethylene glycol dimethacrylate, 1 - 3 parts of siloxane, and 1 - 3 parts of hydroxyphosphonic acid; the temperature of the resin solution tank is set to 40 - 60 °C; the third drying chamber is dried by steam heating, and the temperature is set to 100 - 130 °C.

[0023] In the resin solution, with methanol as the solvent, Amilan CM4000 is a nylon resin suitable for preparing high-performance coating materials. As a coating material, Amilan CM4000 has good abrasion resistance and excellent high-temperature resistance, and can maintain stable performance at high temperatures.

[0024] To avoid uneven dispersion of Amilan CM4000 in methanol and gelation, adding SDBS can improve the dispersion and stability of Amilan CM4000 in methanol. The synergy of nano-alumina and siloxane can improve the abrasion resistance of the coating. Polyethylene glycol dimethacrylate can increase the bonding strength between the coating and the braided reinforcing wire. Hydroxyphosphonic acid has good antioxidant and anti-ultraviolet properties, and can effectively prevent the coating from aging and discoloring in a humid or oxidizing environment.

[0025] Furthermore, in the above preparation process for special sewing threads for automobiles, the rotation speed of the winding is 300 revolutions per minute, and the silicone oil is silicone oil KF-96-200CS.

[0026] Treating the coated braided reinforcing wire with silicone oil KF-96-200CS can reduce the friction coefficient between the fibers, making it easy for the fibers to slide against each other, reducing the generation of static electricity, increasing the softness and feel of the braided reinforcing wire, and improving the abrasion resistance and durability of the braided reinforcing wire.

[0027] Furthermore, in the above preparation process for special sewing threads for automobiles, the pigment solution tank, drying chamber 1, drying chamber 2, resin solution tank, drying chamber 3, and the workshop are all connected to the waste gas treatment device through air collecting hood pipes; the waste gas treatment device includes an activated carbon filter adsorber, a heat pipe waste heat recovery device, a purification device, and an exhaust chimney, and the activated carbon filter adsorber, heat pipe waste heat recovery device, purification device, and exhaust chimney are connected in sequence through air ducts.

[0028] The pigment solution and resin solution contain a high content of organic solvents. During the preparation process, organic waste gas will volatilize, causing air pollution. The organic waste gas of this process has the characteristics of high temperature and high humidity, and waste heat can be recovered and utilized during purification to avoid energy waste.

[0029] Preferably, the outer wall of the air duct is wrapped with glass wool. Insulating the outer wall of the air duct with glass wool can prevent heat dissipation and improve energy utilization.

[0030] Furthermore, in the above preparation process for special sewing threads for automobiles, the purification device includes a purification tower, an axial flow fan, a honeycomb electrode, a high-voltage power supply, a water isolation baffle, an atomizing spray head, a water-air separator, a shell-and-tube heat exchanger, and a circulating spray water pump.

[0031] Among them, an air outlet and a sewage outlet are respectively arranged at the top and bottom of the purification tower. The air outlet is connected to an exhaust chimney through an air duct, and air inlets are arranged on both sides of the purification tower. The internal space of the purification tower is divided into a fan area, a buffer area, a discharge area, a spray area, and a water-gas separation area from top to bottom. An axial flow fan is arranged in the fan area, and a honeycomb electrode is arranged in the discharge area. The honeycomb electrode is connected to a high-voltage power supply. A water-proof baffle is arranged between the discharge area and the spray area. A number of atomizing spray heads are evenly distributed in the upper part of the spray area. The atomizing spray heads are connected to a purification water tank, and the air inlets are located below the spray area. A water-gas separator and a shell-and-tube heat exchanger are sequentially arranged in the water-gas separation area from top to bottom. A circulation port and an overflow port are respectively arranged at the lower part and the upper part on both sides of the water-gas separator. The water outlet, the circulation port, a circulation spray water pump, and the atomizing spray heads of the water-gas separator are connected through a circulation pipe.

[0032] A single treatment process is difficult to achieve the purpose of purifying organic waste gas. The present invention adopts multi-stage treatment of pre-activated carbon filtration and adsorption, waste heat recovery, circulating spray washing purification, and discharge plasma purification, which improves the purification treatment efficiency. The purification treatment efficiency can reach more than 99.9%, and heat energy is also recovered through the heat exchange of a heat pipe type waste heat recovery device and a shell-and-tube heat exchanger.

[0033] The organic waste gas generated by the preparation process of special sewing threads for automobiles first passes through an activated carbon filter adsorber to filter out dust, particulate impurities containing fibers, etc. and primary purification, and then enters a waste heat recovery device for heat energy recovery. After the temperature of the organic waste gas drops, it enters the spray area of the purification tower. The organic waste gas is further absorbed and purified by atomized water droplets, and after cooling and humidifying, the humidity approaches saturation and the temperature further decreases, reaching the safe working temperature for high-voltage discharge purification. Finally, the waste gas passes through active ions such as N, OH, O or high-energy electrons generated during the high-voltage discharge process to form a non-thermal equilibrium plasma, the C-C and CH chemical bonds are broken, and replacement reactions occur with atoms such as H, F, Cl in the organic waste gas for further purification. Then the purified gas is discharged through an axial flow fan.

[0034] A buffer area is arranged between the fan area and the discharge area. The buffer area adopts a structure that is narrow at the top and wide at the bottom, providing a good buffer interval. After the purified gas enters the buffer section, the flow cross-section will increase and the flow velocity will decrease, which also plays a role in liquid distribution and flow splitting for the gas.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] (1) The preparation process of the special sewing thread for automobiles disclosed in the present invention, compared with ordinary polyester yarns, the braided reinforcement thread with a braided structure after being woven by a knitting machine has better uniformity, stability and wear resistance during use, and the braided reinforcement thread is colored, dried and fixed to meet the color requirements of the sewing thread for automobiles;

[0037] (2) In the preparation process of the special sewing thread for automobiles disclosed in the present invention, before the coating treatment, the braided reinforcement thread is pretreated. The pretreatment adopts corona discharge + glue treatment. The two treatment methods cooperate with each other to make the combination of the braided reinforcement thread and the resin solution more firm;

[0038] (3) In the preparation process of the special sewing thread for automobiles disclosed in the present invention, the aqueous PU solution is used as the treatment glue. PU has a solubility parameter similar to that of polyester, and polar groups are introduced to enhance the interfacial combination of the subsequent resin solution and the braided reinforcement thread; the formula design of the resin solution is reasonable. Methanol is used as the solvent. Amilan CM4000 has good wear resistance, chemical corrosion resistance, oil resistance and high temperature resistance as the coating material. Adding SDBS can improve the dispersibility and stability of Amilan CM4000 in methanol. The synergism of nano-alumina and siloxane can improve the wear resistance of the coating. Polyethylene glycol dimethacrylate can increase the bonding strength between the coating and the braided reinforcement thread. Hydroxyphosphonic acid has good antioxidant and anti-ultraviolet properties, which can effectively prevent the coating from aging and discoloring in a humid or oxidative environment;

[0039] (4) In the preparation process of the special sewing thread for automobiles disclosed in the present invention, the waste gas generated in the preparation process is treated by multi-stage treatment including pre-activated carbon filtration and adsorption, waste heat recovery, circulating spray washing, and discharge plasma purification, which improves the purification efficiency. The purification efficiency can reach more than 99.9%, and the heat energy is also recovered and utilized through the heat exchange of a heat pipe type waste heat recovery device and a shell and tube heat exchanger. Brief Description of the Drawings

[0040] Figure 1 It is a process diagram of the preparation process of a special sewing thread for automobiles described in the present invention;

[0041] Figure 2 It is a structural schematic diagram of the waste gas treatment device of the preparation process of a special sewing thread for automobiles described in the present invention;

[0042] In the figure: weaving machine 1, pigment solution tank 2, drying room 1 3, color fixing room 4, corona treatment room 5, glue treatment room 6, slurry pressing roller 7, drying room 2 8, resin solution tank 9, drying room 3 10, gas collecting hood pipe 11, activated carbon filter adsorber 12, heat pipe type waste heat recovery device 13, purification device 14, purification tower 141, air outlet 1411, sewage outlet 1412, air inlet 1413, fan area 1414, Buffer zone 1415, discharge zone 1416, spray zone 1417, water-gas separation zone 1418, circulation port 1419, overflow port 1420, axial flow fan 142, honeycomb electrode 143, high voltage power supply 144, water-blocking baffle 145, atomizing spray head 146, water-gas separator 147, shell and tube heat exchanger 148, circulating spray water pump 149, circulating pipe 150, exhaust chimney 15, and air duct 16. DETAILED DESCRIPTION

[0043] The following is a comparison of Examples 1-5 and Examples 1-4 in combination with specific experimental data, Figure 1 , 2 , the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of the present invention.

[0044] like Figure 1 As shown, the following comparative examples 1-5 and embodiments 1-3 provide a preparation process of special sewing thread for automobiles.

[0045] Among them, in Comparative Examples 1-5 and Examples 1-3, polyester fiber (purchased from Qihao Textile (Changshu) Co., Ltd. EST TB-1), pigment (purchased from Changshu Meikeni Chemical Co., Ltd. HTP YELLOW#B024M), water-based PU (purchased from Anhui Zhongen Chemical Co., Ltd. PU-401), Amilan CM4000 (purchased from Toray Industries, Ltd.), siloxane (vinyl trimethoxysilane, purchased from Evonik Degussa, Germany), hydroxyphosphonic acid (benzoyl hydroxyethylphosphonic acid, purchased from Alfa Aesar (China) Chemical Co., Ltd.), silicone oil (KF-96-200CS, purchased from Shintsu Chemical Industry Co., Ltd.), and other raw materials are all commercially available industrial raw materials.

[0046] In addition, the formula of the resin solution is shown in Table 1.

[0047] Table 1 Test formula of resin solution

[0048]

[0049] Comparative Example 1

[0050] The preparation process of the special sewing thread for automobiles in Comparative Example 1 includes the following steps:

[0051] S1 Coloring: Feed the polyester fiber into the pigment solution tank 2, drying chamber 1 3, and color fixation chamber 4 in sequence for coloring, drying, and color fixation; the pigment solution tank 2 is filled with a pigment solution, the pigment solution includes acetone and pigment, and the mass ratio of acetone to pigment is 80:20. Drying chamber 1 3 is dried by steam heating, the temperature is set at 120 °C, color fixation chamber 4 uses ultraviolet irradiation for color fixation, the ultraviolet power is set at 200 W, and the conveying speed of the polyester fiber is 20 m / min;

[0052] S2 Coating: Feed the above-mentioned polyester fiber into the resin solution tank 9 and drying chamber 3 10 in sequence for coating and drying to obtain a semi-finished special sewing thread for automobiles; the resin solution tank 9 is filled with a resin solution, and the formula of the resin solution is shown in Table 1. The temperature of the resin solution tank 9 is set at 50 °C, drying chamber 3 10 is dried by steam heating, the temperature is set at 120 °C, and the conveying speed of the polyester fiber is 20 m / min;

[0053] S3 Winding and oiling: Wind the semi-finished special sewing thread for automobiles over silicone oil and package it to obtain the special sewing thread for automobiles in Comparative Example 1.

[0054] Comparative Example 2

[0055] The preparation process of the special sewing thread for automobiles in Comparative Example 2 includes the following steps:

[0056] S1 Weaving: Feed the polyester fiber into the knitting machine 1 for weaving to obtain a woven reinforcement thread; the knitting number / strand of the knitting machine is set at 12 outer + 4 cores, and the knitting pitch is set at 3 mm; the diameter of the woven reinforcement thread is 0.6 mm, the breaking strength is 262 N, and the breaking elongation is 24.8% (tested in accordance with GB / T 14344-2022);

[0057] S2 Coloring: Feed the woven reinforcement thread into the pigment solution tank 2, drying chamber 1 3, and color fixation chamber 4 in sequence for coloring, drying, and color fixation; the pigment solution tank 2 is filled with a pigment solution, the pigment solution includes acetone and pigment, and the mass ratio of acetone to pigment is 80:20. Drying chamber 1 3 is dried by steam heating, the temperature is set at 120 °C, color fixation chamber 4 uses ultraviolet irradiation for color fixation, the ultraviolet power is set at 200 W, and the conveying speed of the polyester fiber is 20 m / min;

[0058] S3 Coating: The colored braided reinforcement threads are successively fed into the resin solution tank 9 and the third drying chamber 10 for coating and drying to obtain a semi-finished special sewing thread for automobiles; the resin solution tank 9 contains a resin solution, and the formula of the resin solution is shown in Table 1. The temperature of the resin solution tank 9 is set at 50°C, the third drying chamber 10 is dried by steam heating, the temperature is set at 120°C, and the conveying speed of the polyester fiber is 20 m / min;

[0059] S4 Coiling and Oil Application: The semi-finished special sewing thread for automobiles is coiled through silicone oil and then packaged to obtain the special sewing thread for automobiles of Comparative Example 2.

[0060] Comparative Example 3

[0061] The preparation process of the special sewing thread for automobiles of Comparative Example 3 includes the following steps:

[0062] S1 Braiding: The polyester fiber is fed into the braiding machine 1 for braiding to obtain a braided reinforcement thread; the number of braids / strands of the braiding machine is set at 12 outer + 4 cores, and the braiding pitch is set at 3 mm; the diameter of the braided reinforcement thread is 0.6 mm, the breaking strength is 262 N, and the breaking elongation is 24.8% (tested in accordance with GB / T 14344-2022);

[0063] S2 Coloring: The above-mentioned braided reinforcement thread is successively fed into the pigment solution tank 2, the first drying chamber 3, and the color fixing chamber 4 for coloring, drying, and color fixing; the pigment solution tank 2 contains a pigment solution, the pigment solution includes acetone and pigment, and the mass ratio of acetone to pigment is 80:20. The first drying chamber 3 is dried by steam heating, the temperature is set at 120°C, the color fixing chamber 4 is color fixed by ultraviolet irradiation, the ultraviolet power is set at 200 W, and the conveying speed of the polyester fiber is 20 m / min;

[0064] S3 Pretreatment: The colored braided reinforcement thread is fed into the corona treatment chamber 5 and subjected to corona discharge treatment for 30 s under vacuum conditions. The voltage of the corona discharge treatment is 2 kV, the frequency is 60 Hz, and the gas flow rate is 1.0 L / min;

[0065] S4 Coating: The pretreated braided reinforcement thread is successively fed into the resin solution tank 9 and the third drying chamber 10 for coating and drying to obtain a semi-finished special sewing thread for automobiles; the resin solution tank 9 contains a resin solution, and the formula of the resin solution is shown in Table 1. The temperature of the resin solution tank 9 is set at 50°C, the third drying chamber 10 is dried by steam heating, the temperature is set at 120°C, and the conveying speed of the polyester fiber is 20 m / min;

[0066] S5 Coiling and Oil Application: The semi-finished special sewing thread for automobiles is coiled through silicone oil and then packaged to obtain the special sewing thread for automobiles of Comparative Example 3.

[0067] Comparative Example 4

[0068] The preparation process of the special sewing thread for automobiles in Comparative Example 4 includes the following steps:

[0069] S1 Weaving: Feed the polyester fiber into the weaving machine 1 for weaving to obtain the woven reinforcement thread; the weaving number / strand of the weaving machine is set to 12 outer + 4 cores, and the weaving pitch is set to 3 mm; the diameter of the woven reinforcement thread is 0.6 mm, the breaking strength is 262 N, and the breaking elongation is 24.8% (tested in accordance with GB / T 14344-2022);

[0070] S2 Coloring: Feed the above-mentioned woven reinforcement thread into the pigment solution tank 2, drying chamber 1 3, and color fixation chamber 4 in sequence for coloring, drying, and color fixation; the pigment solution tank 2 contains a pigment solution, and the pigment solution includes acetone and pigment, and the mass ratio of acetone to pigment is 80:20. Drying chamber 1 3 is dried by steam heating, and the temperature is set to 120 °C. Color fixation chamber 4 is color-fixed by ultraviolet irradiation, and the ultraviolet power is set to 200 W. The conveying speed of the polyester fiber is 20 m / min;

[0071] S3 Pretreatment: Feed the colored woven reinforcement thread into the glue treatment chamber 6, immerse it in a 2% aqueous PU solution for 20 s, and then send it to the drying chamber 2 8 for drying after pressing by the pressing roller 7; drying chamber 2 8 is dried by pressurized heating, the pressure is set to 4.5 N, and the temperature is set to 120 °C;

[0072] S4 Coating: Feed the pretreated woven reinforcement thread into the resin solution tank 9 and drying chamber 3 10 in sequence for coating and drying to obtain a semi-finished special sewing thread for automobiles; the resin solution tank 9 contains a resin solution, and the formula of the resin solution is shown in Table 1. The temperature of the resin solution tank 9 is set to 50 °C. Drying chamber 3 10 is dried by steam heating, and the temperature is set to 120 °C. The conveying speed of the polyester fiber is 20 m / min;

[0073] S5 Winding and oiling: Wind the above-mentioned semi-finished special sewing thread for automobiles through silicone oil, and package it to obtain the special sewing thread for automobiles in Comparative Example 4.

[0074] Comparative Example 5

[0075] The preparation process of the special sewing thread for automobiles in Comparative Example 5 includes the following steps:

[0076] S1 Weaving: Feed the polyester fiber into the weaving machine 1 for weaving to obtain the woven reinforcement thread; the weaving number / strand of the weaving machine is set to 12 outer + 4 cores, and the weaving pitch is set to 3 mm; the diameter of the woven reinforcement thread is 0.6 mm, the breaking strength is 262 N, and the breaking elongation is 24.8% (tested in accordance with GB / T 14344-2022);

[0077] S2 Coloring: Feed the above-mentioned braided reinforcing threads into the pigment solution tank 2, drying chamber 1 3, and color fixing chamber 4 in sequence for coloring, drying, and color fixing; the pigment solution tank 2 is internally provided with a pigment solution, the pigment solution includes acetone and pigment, and the mass ratio of acetone to pigment is 80:20. Drying chamber 1 3 uses steam heating for drying, the temperature is set at 120 °C, color fixing chamber 4 uses ultraviolet irradiation for color fixing, the ultraviolet power is set at 200 W, and the conveying speed of the polyester fiber is 20 m / min;

[0078] S3 Pretreatment: Feed the colored braided reinforcing threads into the glue treatment chamber 6, immerse them in an aqueous PU solution with a mass fraction of 3% for 20 s, and then feed them into drying chamber 2 8 for drying after pressing by the pressure roller 7; drying chamber 2 8 uses pressurized heating for drying, the pressure is set at 4.5 N, and the temperature is set at 120 °C;

[0079] S4 Coating: Feed the pretreated braided reinforcing threads into the resin solution tank 9 and drying chamber 3 10 in sequence for coating and drying to obtain a semi-finished special sewing thread for automobiles; the resin solution tank 9 is internally provided with a resin solution, and the formula of the resin solution is shown in Table 1. The temperature of the resin solution tank 9 is set at 50 °C, drying chamber 3 10 uses steam heating for drying, the temperature is set at 120 °C, and the conveying speed of the polyester fiber is 20 m / min;

[0080] S5 Winding and oiling: Wind the above-mentioned semi-finished special sewing thread for automobiles through silicone oil, and package it to obtain the special sewing thread for automobiles of Comparative Example 5.

[0081] Example 1

[0082] The preparation process of the special sewing thread for automobiles in Example 1 includes the following steps:

[0083] S1 Braiding: Feed the polyester fiber into the braiding machine 1 for braiding to obtain a braided reinforcing thread; the number of braids / strands of the braiding machine is set at 12 outer + 4 cores, and the braiding pitch is set at 3 mm; the diameter of the braided reinforcing thread is 0.6 mm, the breaking strength is 262 N, and the breaking elongation is 24.8% (the test is carried out in accordance with GB / T 14344-2022);

[0084] S2 Coloring: Feed the above-mentioned braided reinforcing threads into the pigment solution tank 2, drying chamber 1 3, and color fixing chamber 4 in sequence for coloring, drying, and color fixing; the pigment solution tank 2 is internally provided with a pigment solution, the pigment solution includes acetone and pigment, and the mass ratio of acetone to pigment is 80:20. Drying chamber 1 3 uses steam heating for drying, the temperature is set at 120 °C, color fixing chamber 4 uses ultraviolet irradiation for color fixing, the ultraviolet power is set at 200 W, and the conveying speed of the polyester fiber is 20 m / min;

[0085] S3 Pretreatment: The colored braided reinforcement wire is first fed into the corona treatment chamber 5, where corona discharge treatment is carried out for 30 s under vacuum conditions. The voltage of the corona discharge treatment is 2 kV, the frequency is 60 Hz, and the gas flow rate is 1.0 L / min. Then it is fed into the glue treatment chamber 6, immersed in an aqueous PU solution with a mass fraction of 3% for 20 s, and finally sent to the second drying chamber 8 for drying after being pressed by the pressure roller 7. The second drying chamber 8 uses pressurized heating for drying, with the pressure set at 4.5 N and the temperature set at 120 °C;

[0086] S4 Coating: The pretreated braided reinforcement wire is successively fed into the resin solution tank 9 and the third drying chamber 10 for coating and drying to obtain a semi-finished special sewing thread for automobiles. The resin solution tank 9 contains a resin solution, and the formula of the resin solution is shown in Table 1. The temperature of the resin solution tank 9 is set at 50 °C, the third drying chamber 10 uses steam heating for drying, the temperature is set at 120 °C, and the conveying speed of the polyester fiber is 20 m / min;

[0087] S5 Winding and oiling: The above-mentioned semi-finished special sewing thread for automobiles is wound through silicone oil and then packaged to obtain the special sewing thread for automobiles in Example 1.

[0088] Example 2

[0089] The preparation process of the special sewing thread for automobiles in Example 2 includes the following steps:

[0090] S1 Braiding: The polyester fiber is fed into the braiding machine 1 for braiding to obtain a braided reinforcement wire. The braiding number / strand of the braiding machine is set to 12 outer + 4 cores, and the braiding pitch is set to 3 mm. The diameter of the braided reinforcement wire is 0.6 mm, the breaking strength is 262 N, and the breaking elongation is 24.8% (the test is carried out in accordance with GB / T 14344-2022);

[0091] S2 Coloring: The above-mentioned braided reinforcement wire is successively fed into the pigment solution tank 2, the first drying chamber 3, and the color fixing chamber 4 for coloring, drying, and color fixing. The pigment solution tank 2 contains a pigment solution, and the pigment solution includes acetone and pigment. The mass ratio of acetone to pigment is 80:20. The first drying chamber 3 uses steam heating for drying, the temperature is set at 120 °C, the color fixing chamber 4 uses ultraviolet irradiation for color fixing, the ultraviolet power is set at 200 W, and the conveying speed of the polyester fiber is 20 m / min;

[0092] S3 Pre-treatment: Feed the colored braided reinforcement wire into the corona treatment chamber 5 first, and perform corona discharge treatment for 30 s under vacuum conditions. The voltage of the corona discharge treatment is 2 kV, the frequency is 60 Hz, and the gas flow rate is 1.0 L / min. Then feed it into the glue treatment chamber 6, immerse it in an aqueous PU solution with a mass fraction of 3% for 20 s, and finally send it to the second drying chamber 8 for drying after pressing by the pressure roller 7. The second drying chamber 8 uses pressurized heating for drying, with the pressure set at 4.5 N and the temperature set at 120 °C.

[0093] S4 Coating: Feed the pre-treated braided reinforcement wire into the resin solution tank 9 and the third drying chamber 10 in sequence for coating and drying to obtain a semi-finished special sewing thread for automobiles. The resin solution tank 9 contains a resin solution, and the formula of the resin solution is shown in Table 1. The temperature of the resin solution tank 9 is set at 50 °C, the third drying chamber 10 uses steam heating for drying, the temperature is set at 120 °C, and the conveying speed of the polyester fiber is 20 m / min.

[0094] S5 Winding and oiling: Wind the above semi-finished special sewing thread for automobiles through silicone oil, and package it to obtain the special sewing thread for automobiles in Example 2.

[0095] Example 3

[0096] The preparation process of the special sewing thread for automobiles in Example 3 includes the following steps:

[0097] S1 Braiding: Feed the polyester fiber into the braiding machine 1 for braiding to obtain a braided reinforcement wire. The number of braids / strands of the braiding machine is set to 12 outer + 4 cores, and the braiding pitch is set to 3 mm. The diameter of the braided reinforcement wire is 0.6 mm, the breaking strength is 262 N, and the breaking elongation is 24.8% (tested in accordance with GB / T 14344-2022).

[0098] S2 Coloring: Feed the above braided reinforcement wire into the pigment solution tank 2, the first drying chamber 3, and the color fixation chamber 4 in sequence for coloring, drying, and color fixation. The pigment solution tank 2 contains a pigment solution, and the pigment solution includes acetone and pigment. The mass ratio of acetone to pigment is 80:20. The first drying chamber 3 uses steam heating for drying, the temperature is set at 120 °C, the color fixation chamber 4 uses ultraviolet irradiation for color fixation, the ultraviolet power is set at 200 W, and the conveying speed of the polyester fiber is 20 m / min.

[0099] S3 pretreatment: the colored braided reinforcement wire is first sent to the corona treatment chamber 5, and corona discharge treatment is carried out for 30 seconds under vacuum conditions. The voltage of the corona discharge treatment is 2kV, the frequency is 60Hz, and the gas flow rate is 1.0L / min; then sent to the glue treatment chamber 6, immersed in a 3% aqueous PU solution for 20 seconds, and finally sent to the drying chamber 8 for drying after being squeezed by the squeezing roller 7; the drying chamber 8 adopts pressurized heating drying, the pressure is set to 4.5N, and the temperature is set to 120℃;

[0100] S4 coating: the pretreated braided reinforcing wire is sequentially sent to the resin solution tank 9 and the drying chamber 3 10 for coating and drying to obtain a semi-finished special sewing thread for automobiles; the resin solution tank 9 contains a resin solution, the formula of the resin solution is shown in Table 1, the temperature of the resin solution tank 9 is set to 50°C, the drying chamber 3 10 is steam-heated and dried, the temperature is set to 120°C, and the conveying speed of the polyester fiber is 20m / min;

[0101] S5: winding the semi-finished special sewing thread for automobiles with silicone oil, and then packaging to obtain the special sewing thread for automobiles of Example 3.

[0102] First, the contact angle test was performed on the polyester fiber of comparative example 1 before coating, comparative examples 2-5 before coating, and the braided reinforcement wire of examples 1-3. The test results are shown in Table 2. The test method is as follows:

[0103] (1) Contact angle measurement: The contact angle was measured by an optical measurement method. Specifically, a 100 pL injection unit was used to allow a 10 pL ultrapure water droplet to fall onto the fiber. A 20x objective lens and 250 fps CCD were used to capture the entire contact process between the droplet and the fiber. The ellipse method was selected using the instrument's own software to calculate the contact angle of the fiber. Four levels were selected for each sample.

[0104] Table 2 Contact angle test results

[0105] Contact angle (°) Comparative Example 1 85.32 Comparative Example 2 87.53 Comparative Example 3 76.27 Comparative Example 4 64.45 Comparative Example 5 62.54 Example 1 53.06 Example 2 54.03 Example 3 53.27

[0106] As can be seen from Table 2, compared with Comparative Examples 1 and 2 without pretreatment, the contact angles of the braided reinforcing threads in Comparative Examples 3-5 and Examples 1-3 after pretreatment are significantly decreased, and the hydrophilicity is increased. Among them, compared with Comparative Example 3 with only corona discharge pretreatment, the decrease in the contact angle of the braided reinforcing threads in Comparative Examples 4 and 5 with only glue treatment is greater. For Examples 1-3 with corona discharge + glue treatment pretreatment, the surface properties of the braided reinforcing threads are effectively improved by corona discharge first, free radicals are introduced to improve the surface activity, and the affinity and adhesion strength of the subsequent aqueous PU solution and resin solution to the braided reinforcing threads are improved. Then, the braided reinforcing threads are treated with glue to introduce polar groups to enhance the interfacial bonding between the resin solution and the braided reinforcing threads. The two treatment methods cooperate with each other, resulting in the largest decrease in the contact angle and the best hydrophilicity, which is beneficial to making the combination of the braided reinforcing threads and the resin solution more firm.

[0107] Secondly, the thermal stability performance, mechanical properties, and wear resistance of the special sewing threads for automobiles in Comparative Examples 1-5 and Examples 1-3 were tested. The test results are shown in Tables 3 and 4, and the test methods are as follows:

[0108] (1) Thermal stability performance test: Using a differential scanning calorimeter, nitrogen was introduced, and the temperature range was 20°C - 300°C to test the melting points of the special sewing threads for automobiles in Comparative Examples 1-5 and Examples 1-3.

[0109] (2) Mechanical properties test: In accordance with GB / T 14344-2022.

[0110] (3) Wear resistance test: Using 150CW sandpaper as the abrasive, the weight of the heavy hammer was selected as 50g, the reciprocating speed of the grinding roller was fixed at (60±1) times / min, the ambient temperature of the test chamber was 20°C, and the relative humidity was 65%. The wear resistance of the special sewing threads for automobiles in Comparative Examples 1-5 and Examples 1-3 was tested by changing the mass of the hanging weights. 8 pieces were placed in each group, two groups were tested each time, and a total of 5 tests were conducted. After the test, the single value, maximum value, and minimum value were recorded, and the average value and coefficient of variation of the friction times were calculated.

[0111] Table 3 Test results of thermal stability performance and mechanical properties

[0112]

[0113]

[0114] Table 4 Test results of wear resistance

[0115]

[0116] As can be seen from Tables 2, 3, and 4, compared with Comparative Example 2 without pretreatment, the contact angles of the braided reinforcing wires in Comparative Examples 3-5 and Examples 1-3 after pretreatment are significantly decreased, the hydrophilicity is increased, the adhesion of the coating to the braided reinforcing wires is improved, thereby improving the effect of the coating, and the thermal stability performance, mechanical properties, and wear resistance are all enhanced. Among them, Examples 1-3 using corona discharge + glue treatment for pretreatment have more excellent coating effects. And Example 3 with SDBS, nano-aluminum oxide, silicone, polyethylene glycol dimethacrylate, and hydroxyphosphonic acid added to the resin solution has the best comprehensive performance.

[0117] As Figure 2 shown, the following Example 4 provides an exhaust gas treatment device for the preparation process of a special sewing thread for automobiles.

[0118] Example 4

[0119] The exhaust gas treatment device for the preparation process of the special sewing thread for automobiles includes a gas collecting hood pipe 11, an activated carbon filter adsorber 12, a heat pipe type waste heat recovery device 13, a purification device 14, an exhaust chimney 15, and an air duct 16. The pigment solution and the resin solution contain a relatively high content of organic solvents, and the treatment glue solution is heated and decomposed to generate organic waste gas. During the drying process, the organic waste gas will volatilize. After being collected by the gas collecting hood pipe 11 and transmitted through the air duct 16, it first passes through the activated carbon filter adsorber 12 to filter out dust, particulate impurities, etc. containing fibers, and then enters the heat pipe type waste heat recovery device 13 for heat energy recovery. After the temperature of the organic waste gas drops, it enters the purification device 14 for purification, and finally the purified gas is discharged from the exhaust chimney 15.

[0120] Furthermore, the purification device 14 includes a purification tower 141, an axial flow fan 142, a honeycomb electrode 143, a high-voltage power supply 144, a water separation baffle 145, an atomizing spray head 146, a water-gas separator 147, a shell-and-tube heat exchanger 148, and a circulating spray water pump 149. The organic waste gas after heat energy is recovered by the waste heat recovery device 13 enters the spray area 1417 of the purification tower 141 after the temperature drops. The organic waste gas is further absorbed and purified by the atomized water droplets sprayed by the atomizing spray head 146, and after being cooled and humidified, the humidity approaches saturation and the temperature further decreases, reaching the safe working temperature for high-voltage discharge purification. Finally, the waste gas enters the discharge area 1416 of the purification tower 141, and through active ions such as N, OH, O or high-energy electrons generated during the high-voltage discharge process, a non-thermal equilibrium plasma is formed, the C-C and CH chemical bonds are broken, and the H, F, Cl and other atoms in the organic waste gas are replaced for further purification, and then the purified gas is discharged through the axial flow fan 142.

[0121] The organized waste gas of the device without waste gas treatment device and the device with waste gas treatment device (Example 4) was detected according to the standard in Table 1 of "Jiangsu Local Standard - Integrated Emission Standard of Air Pollutants" (DB32 / 4041-2021), and the detection results are shown in Table 5-6.

[0122] Table 5 Detection Results of Organized Waste Gas of the Device without Waste Gas Treatment Device

[0123]

[0124] Table 6 Detection Results of Organized Waste Gas of Example 4

[0125]

[0126]

[0127] It can be seen from Table 5 and Table 6 that the multi-stage treatment of the present invention, which adopts pre-activated carbon filtration and adsorption, waste heat recovery, circulating spray washing purification, and discharge plasma purification, improves the purification efficiency. The purification efficiency of Example 4 can reach more than 99.9%.

[0128] There are many specific application ways of the present invention, and the above-mentioned is only the preferred embodiment of the present invention. It should be noted that the above embodiments are only used to illustrate the present invention, and do not limit the protection scope of the present invention. For those of ordinary skill in the art, several improvements can be made without departing from the principle of the present invention, and these improvements should also be regarded as the protection scope of the present invention.

Claims

1. A preparation process for special sewing thread for automobiles, characterized in that, It includes the following steps: S1 Weaving: Feed polyester fibers into a weaving machine (1) for weaving to obtain woven reinforcing threads; S2 Coloring: Feed the above-mentioned woven reinforcing threads into a pigment solution tank (2), a first drying chamber (3), and a color fixing chamber (4) in sequence for coloring, drying, and color fixing; the pigment solution tank (2) is internally provided with a pigment solution, and the conveying speed of the woven reinforcing threads is 10 - 50 m / min; S3 Pretreatment: Feed the colored woven reinforcing threads into a corona treatment chamber (5) first, and perform corona discharge treatment for 30 - 60 s under vacuum conditions; then feed them into a glue treatment chamber (6) and immerse them in the treatment glue solution for 15 - 45 s; then press them through a pressure roller (7) and feed them into a second drying chamber (8) for drying; in S3, the voltage of the corona discharge treatment is 1.5 - 3 kV, the frequency is 40 - 60 Hz, and the gas flow rate is 0.8 - 1.2 L / min; the treatment glue solution uses an aqueous PU solution with a mass fraction of 1 - 10%; the second drying chamber (8) uses pressurized heating for drying, the pressure is set to 4 - 7 N, and the temperature is set to 100 - 130 °C; S4 Coating: Feed the pretreated woven reinforcing threads into a resin solution tank (9) and a third drying chamber (10) in sequence for coating and drying to obtain a semi-finished special sewing thread for automobiles; the resin solution tank (9) is internally provided with a resin solution, and the conveying speed of the woven reinforcing threads is 10 - 50 m / min; in S4, the resin solution includes the following raw materials in parts by weight: 80 - 90 parts of methanol, 5 - 10 parts of Amilan CM4000, 2 - 5 parts of SDBS, 1 - 3 parts of nano-aluminum oxide, 1 - 3 parts of polyethylene glycol dimethacrylate, 1 - 3 parts of siloxane, and 1 - 3 parts of hydroxyphosphonic acid; the temperature of the resin solution tank (9) is set to 40 - 60 °C; the third drying chamber (10) uses steam heating for drying, and the temperature is set to 100 - 130 °C; S5 Winding and oiling: Wind the above-mentioned semi-finished special sewing thread for automobiles through silicone oil, and package it to obtain a finished special sewing thread for automobiles.

2. The preparation process of the special sewing thread for automobiles according to claim 1, wherein, In S1, the weaving number / strand of the weaving machine (1) is set to 12 outer + 4 cores, the weaving pitch is set to 2 - 4 mm, the diameter of the woven reinforcing thread is 0.6 - 1.2 mm, the breaking strength is 200 - 300 N, and the breaking elongation is 20 - 30%.

3. The preparation process of the special sewing thread for automobiles according to claim 1, characterized in that, In S2, the pigment solution includes acetone and pigment, and the mass ratio of acetone to pigment is 10 - 30:1; the first drying chamber (3) uses steam heating for drying, and the temperature is set to 100 - 130 °C; the color fixing chamber (4) uses ultraviolet irradiation for color fixing, and the ultraviolet power is set to 100 - 300 W.

4. The preparation process of the special sewing thread for automobiles according to claim 1, characterized in that, In S5, the rotation speed of the winding is 300 revolutions / min, and the silicone oil is silicone oil KF-96-200CS.

5. The preparation process of the special sewing thread for automobiles according to claim 1, characterized in that, The drying chamber 1 (3), drying chamber 2 (8), and drying chamber 3 (10) are all connected to the waste gas treatment device through a gas collecting hood pipe (11); the waste gas treatment device includes an automatic filter (12), a heat pipe type waste heat recovery device (13), a purification device (14), and an exhaust chimney (15), and the automatic filter (12), the heat pipe type waste heat recovery device (13), the purification device (14), and the exhaust chimney (15) are sequentially connected through an air duct (16).

6. The preparation process of the special sewing thread for automobiles according to claim 5, characterized in that, The purification device (14) includes a purification tower (141), an axial flow fan (142), a honeycomb electrode (143), a high-voltage power supply (144), a water separation baffle (145), an atomizing spray head (146), a water-air separator (147), a shell and tube heat exchanger (148), and a circulating spray water pump (149).

7. The preparation process of the special sewing thread for automobiles according to claim 6, characterized in that, An air outlet (1411) and a sewage outlet (1412) are respectively arranged at the top and bottom of the purification tower (141), the air outlet (1411) is connected to the exhaust chimney (15) through an air duct (16), and air inlets (1413) are arranged on both sides of the purification tower (141); the internal space of the purification tower (141) is divided into a fan area (1414), a buffer area (1415), a discharge area (1416), a spray area (1417), and a water-air separation area (1418) from top to bottom; the axial flow fan (142) is arranged in the fan area (1414), the honeycomb electrode (143) is arranged in the discharge area (1416), and the honeycomb electrode (143) is connected to the high-voltage power supply (144); a water separation baffle (145) is arranged between the discharge area (1416) and the spray area (1417); a plurality of atomizing spray heads (146) are evenly distributed in the upper part of the spray area (1417), and the air inlets (1413) are located below the spray area (1417); the water-air separator (147), the shell and tube heat exchanger (148) are sequentially arranged in the water-air separation area (1418) from top to bottom, a circulation port (1419) and an overflow port (1420) are respectively arranged at the lower part and the upper part on both sides of the water-air separator (147), and the water outlet of the water-air separator (147), the circulation port (1419), the circulating spray water pump (149), and the atomizing spray head (146) are connected through a circulation pipe (150).

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