A seamless elastic heat-sealing one-piece molding process for polo shirts

Abstract

This invention relates to the field of garment manufacturing and processing technology, and discloses a manufacturing process for a seamless elastic pressure-sealed one-piece molded polo shirt, comprising the following steps: first, cutting high-elastic knitted fabric into polo shirt component pieces, and then performing micro-melting edge sealing treatment on the edges of the polo shirt component pieces; subsequently, applying a heat-melting reactive moisture-curing polyurethane liquid adhesive to the splicing edges of the polo shirt component pieces after the micro-melting edge sealing treatment, wherein the adhesive is applied according to the mechanical performance requirements of different parts of the polo shirt. By applying reactive moisture-curing polyurethane liquid adhesive to the splicing edges of the polo shirt component pieces after the micro-melting edge sealing treatment, excellent local structural rigidity is provided without traditional lining, thereby perfectly preserving the original high elasticity and breathable micropores of the fabric. Simultaneously, after the water vapor crosslinking reaction is completed, an instantaneous high-intensity vacuum dehydration and shaping process is introduced, which can further increase the dimensional stability and lasting flatness of the polo shirt at the factory.

Description

Technical Field

[0001] This invention relates to the field of garment manufacturing and processing technology, specifically to a seamless elastic heat-sealing one-piece molding process for polo shirts. Background Technology

[0002] In recent years, as consumers have increasingly demanded higher comfort and minimalist aesthetics in clothing, seamless clothing has gradually become an important development trend in high-end sportswear and casual wear (such as polo shirts) because it eliminates the friction and visible stitches caused by traditional sewing threads. Currently, the industry generally relies on solid hot melt adhesive tape (such as TPU or PES film) as the bonding medium to manufacture seamless clothing. The basic process is to place the solid tape between the edges of two pieces of fabric, and then use a flatbed press to apply high temperature and mechanical pressure on a two-dimensional workbench to melt the adhesive film and bond the fabric.

[0003] However, this traditional planar lamination process has revealed significant limitations in practical applications. In terms of material structure and mechanical properties, after the solid hot melt adhesive film melts and cools at high temperatures, it inevitably forms a continuous, dense, and inflexible hard adhesive layer in the fabric seam area. For the functional high-elastic knitted fabric commonly used in polo shirts, this continuous hard structure acts like a rigid frame, completely locking the sliding space between the fabric yarns. This causes the seam to completely lose the original high elasticity of the fabric. When consumers stretch their limbs significantly, they will clearly feel the stiff pulling and restraint at the seam. Long-term stress concentration can even easily cause the fabric to tear. At the same time, the dense continuous tape completely blocks the microscopic breathable pores of the knitted fabric, making it impossible for moisture to escape from areas prone to sweating, such as the armpits and side seams. This easily leads to stuffiness and sweat accumulation, seriously reducing the comfort of the garment.

[0004] In terms of molding and pattern making, the traditional high-temperature two-dimensional flat pressing method is inherently contradictory to the three-dimensional spatial properties of clothing. The human body has complex three-dimensional curved surface features. The shoulder seams, collar, armholes, and other parts of a polo shirt are designed with three-dimensional curved structures. Forcing these naturally three-dimensionally spliced ​​adhesive-coated pieces onto a two-dimensional flat platform and applying vertical downward pressure for forced bonding will inevitably cause excess fabric to physically overlap and be forcibly squeezed in the curved transition areas. This easily creates irreversible creases and harsh wrinkles at key connection points of the garment, severely damaging the natural drape and three-dimensional shape of the clothing, resulting in an extremely uneven appearance. The lack of a consistent yield rate makes it difficult to guarantee the quality of products. To improve the stiffness caused by the aforementioned tapes, the industry has tried to introduce reactive moisture-curing liquid adhesives for coating and bonding. However, in actual garment bonding environments, the coated liquid adhesive is tightly sandwiched between two layers of fabric in a highly sealed interlayer state. Natural moisture in the air is extremely difficult to penetrate the dense fabric fibers and seep into the adhesive seam, resulting in an extremely long cross-linking and curing cycle for the adhesive. It often requires several days of rest to reach a safe tear resistance strength, which is completely unacceptable for the continuous and efficient production rhythm of modern garment industry. Therefore, this invention designs a seamless elastic bonding one-piece molding process for POLO shirts based on the problems mentioned above. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a seamless elastic heat-sealing one-piece molding process for POLO shirts, which solves the problems of stiff seams and loss of elasticity, as well as creases and dead wrinkles in three-dimensional areas, caused by the use of traditional solid adhesive film and two-dimensional planar heat pressing processes in existing seamless garment manufacturing.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a seamless elastic heat-sealing integrated molding process for manufacturing polo shirts, comprising the following steps: S1. First, cut the high-elastic knitted fabric into pieces for each part of the POLO shirt, and then perform micro-melting edge sealing on the edges of each piece of the POLO shirt. S2. Subsequently, a reactive, moisture-curing polyurethane liquid adhesive in a heated and molten state is applied to the splicing edges of the polo shirt pieces after micro-melting edge sealing treatment. According to the mechanical performance requirements of different parts of the polo shirt, high-density continuous linear adhesive is applied to the collar and placket areas of the polo shirt pieces, and micro-droplet matrix adhesive is applied to the armhole, shoulder seam, and side seam areas of the polo shirt pieces to obtain adhesive-coated pieces. S3. Then, the adhesive-coated cut pieces are assembled according to the three-dimensional structure of the polo shirt and placed on the outside of the 3D porous bionic mold with micropores evenly distributed on the surface. The air extraction system inside the 3D porous bionic mold is activated to establish an initial negative pressure, so that the splicing edges of the adhesive-coated cut pieces are adsorbed and attached to the surface of the 3D porous bionic mold, forming a three-dimensional splicing state. S4. While maintaining the three-dimensional assembly state, pulsed high-temperature water vapor is sprayed onto the assembly edge through the micropores on the surface of the 3D porous biomimetic mold, and vacuum negative pressure and micro positive pressure steam pulses are alternately executed at a set frequency to drive the reactive moisture-curing polyurethane liquid adhesive sandwiched between the assembly edges to undergo dynamic penetration and water vapor cross-linking reaction, thereby obtaining the cross-linked POLO shirt semi-finished product. S5. After the water-vapor crosslinking reaction is completed, stop spraying the pulsed high-temperature water vapor, switch the internal air path of the 3D porous bionic mold to a high-intensity vacuum negative pressure state, remove the moisture from the crosslinked POLO shirt semi-finished product and cool and shape it to obtain an integrated POLO shirt, restore the pressure inside the 3D porous bionic mold to normal pressure, demold the integrated POLO shirt from the 3D porous bionic mold, and finally obtain a seamless elastic pressure-bonded integrated POLO shirt.

[0007] Preferably, in the process of cutting the high-elastic knitted fabric into polo shirt pieces, a carbon dioxide laser cutting device is used for cutting and the micro-melting edge sealing process. The cutting power setting range of the carbon dioxide laser cutting device is 35W-85W, and the cutting speed setting range is 200mm / s-500mm / s.

[0008] Preferably, during the application of the reactive moisture-curing polyurethane liquid adhesive in a heated and molten state, the heating temperature of the adhesive application equipment is set to 95℃-130℃.

[0009] Preferably, in the high-density continuous linear dispensing, the width of a single dispensing line is set to 1.5mm-3.0mm, and the amount of dispensing is controlled at 30g / m²-50g / m²; the microdroplet matrix dispensing is a honeycomb microdroplet matrix dispensing, the diameter of a single droplet is set to 0.3mm-0.8mm, the center-to-center distance between adjacent droplets is set to 0.5mm-1.5mm, and the amount of dispensing is controlled at 10g / m²-25g / m².

[0010] Preferably, the pore size of the micropores on the surface of the 3D porous biomimetic mold ranges from 0.5mm to 2.0mm, and the pore density is 5 pores / cm² to 20 pores / cm²; during the process of establishing the initial negative pressure, the value of the initial negative pressure is set to -50kPa to -80kPa and maintained for 3s to 8s.

[0011] Preferably, during the process of injecting pulsed high-temperature water vapor, the temperature of the pulsed high-temperature water vapor is set to 110℃-140℃; the pressure range of the micro-positive pressure steam pulse is 10kPa-30kPa.

[0012] Preferably, the set frequency is 0.2Hz-0.5Hz; the entire process of alternating vacuum negative pressure and micro positive pressure steam pulse is executed for a total of 3-8 alternating cycles.

[0013] Preferably, under the high-intensity vacuum negative pressure state, the negative pressure value of the high-intensity vacuum negative pressure state is set to -90kPa to -98kPa, and the extraction time under this state is 5s-15s.

[0014] Preferably, before demolding the one-piece molded polo shirt from the 3D porous bionic mold, the time for restoring the pressure inside the 3D porous bionic mold to normal pressure is controlled within 1s-3s.

[0015] Preferably, a seamless elastic pressure-sealed one-piece molded POLO shirt is provided, which does not contain sewing threads and whose spliced ​​edges are connected by a reactive moisture-curing polyurethane liquid adhesive. The raw material components and mass percentages of the reactive moisture-curing polyurethane liquid adhesive before curing include: Isocyanate-terminated polyurethane prepolymer: 55.0wt%-70.0wt%; Thermoplastic polyurethane resin: 15.0wt%-25.0wt%; Tackifying resin: 5.0wt%-12.0wt%; Rheology modifier: 1.5wt%-5.0wt%; Organotin catalysts: 0.1wt%-0.5wt%; Antioxidants and UV absorbers: 0.4wt%-1.5wt%.

[0016] This invention provides a seamless, elastic, one-piece molding process for manufacturing polo shirts. It offers the following advantages: 1. This invention applies reactive moisture-curing polyurethane liquid adhesive to the splicing edges of POLO shirt pieces after micro-melting edge sealing treatment, and innovatively adopts a differentiated dynamic dispensing process to give the area excellent natural stiffness and structural rigidity without traditional lining, thereby perfectly preserving the original high elasticity and breathable micropores of the fabric and greatly improving the comfort of wearing it.

[0017] 2. This invention introduces a 3D porous biomimetic mold with uniformly distributed micropores on its surface and an initial negative pressure positioning technology. The adhesive-coated cut pieces are placed outside the 3D mold that matches the ergonomic pattern. The initial negative pressure is established by the internal air extraction system of the mold. The external atmospheric pressure can be used to uniformly, smoothly and without dead angles forcefully adsorb and adhere the splicing edges of the 2D cut pieces to the complex 3D curved surface. This fundamentally eliminates the creases and fabric accumulation caused by mechanical pressure and achieves a truly seamless adhesive bonding and one-piece molding.

[0018] 3. This invention cleverly overcomes the technical bottleneck of the difficulty in rapidly and uniformly curing liquid adhesive between closed fabric layers by using alternating pressure and pulsed steam coupling crosslinking process. This deep linkage between thermodynamic fluid control and chemical reaction greatly enhances the mechanical interlocking force between the adhesive and the high-elastic knitted fabric, and significantly improves the peel strength and tear resistance at the seam.

[0019] 4. This invention effectively overcomes the problem of post-curing shrinkage and deformation caused by residual moisture and latent heat after garment demolding by introducing an instantaneous high-intensity vacuum dehydration and shaping process after the water-vapor cross-linking reaction. The high-speed flowing vacuum negative pressure airflow quickly removes the latent heat generated by chemical cross-linking. This second-level thermophysical locking mechanism completely shapes the three-dimensional composite structure of the fabric and adhesive, giving the POLO shirt excellent factory dimensional stability and lasting flatness.

[0020] 5. This invention uses specific equipment to prepare cut pieces of high-elastic knitted fabric and simultaneously performs micro-melting edge sealing treatment, laying a reliable physical foundation for subsequent high-pressure airflow impact and precision adhesive application. This not only eliminates the risk of fiber scattering and edge breakage in the fabric under subsequent high-intensity alternating pressure airflow environment, but also provides a smoother and stronger coating base for reactive moisture-curing polyurethane liquid adhesive. From the source of the manufacturing process, it ensures the smoothness of the seamless POLO shirt seams and the overall structural strength. Attached Figure Description

[0021] Figure 1 This is one of the schematic diagrams of the manufacturing process of the present invention; Figure 2 This is a second schematic diagram of the manufacturing process of the present invention; Figure 3 This is the third schematic diagram of the manufacturing process of the present invention; Figure 4 This is the fourth schematic diagram of the manufacturing process of the present invention. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Please see the appendix Figure 1 - Appendix Figure 4 This invention provides a manufacturing process for a seamless, elastic, one-piece molded polo shirt, comprising the following steps: S1. First, cut the high-elastic knitted fabric into polo shirt pieces, and then perform micro-melting edge sealing on the edges of each polo shirt piece. During the process of cutting the high-elastic knitted fabric into polo shirt pieces, a carbon dioxide laser cutting device is used for cutting and micro-melting edge sealing. The cutting power setting range of the carbon dioxide laser cutting device is 35W-85W, and the cutting speed setting range is 200mm / s-500mm / s. A seamless, elastic, pressure-sealed, one-piece molded polo shirt, which does not contain sewing threads, has its seam edges bonded together using a reactive moisture-curing polyurethane liquid adhesive; the raw material components and mass percentages of the reactive moisture-curing polyurethane liquid adhesive before curing include: Isocyanate-terminated polyurethane prepolymer: 55.0wt%-70.0wt%; Thermoplastic polyurethane resin: 15.0wt%-25.0wt%; Tackifying resin: 5.0wt%-12.0wt%; Rheology modifier: 1.5wt%-5.0wt%; Organotin catalysts: 0.1wt%-0.5wt%; Antioxidants and UV absorbers: 0.4wt%-1.5wt%; Specifically, before processing, prepare the reactive moisture-curing polyurethane liquid adhesive required for this process. The raw material components and mass percentages of the adhesive before curing include: isocyanate-terminated polyurethane prepolymer: 55.0wt%-70.0wt%; thermoplastic polyurethane resin: 15.0wt%-25.0wt%; tackifying resin: 5.0wt%-12.0wt%; rheology modifier: 1.5wt%-5.0wt%; organotin catalyst: 0.1wt%-0.5wt%; antioxidant and UV absorber: 0.4wt%-1.5wt%. Among them, the isocyanate-terminated polyurethane prepolymer serves as the main structure for reactive crosslinking, and the thermoplastic polyurethane resin is used to provide a certain initial tack before complete crosslinking. The prepared high-elastic knitted fabric is then laid flat on the cutting platform, and a carbon dioxide laser cutting device is used to cut it according to the preset polo shirt pattern. During this process, the cutting power of the carbon dioxide laser cutting device is set within the range of 35W-85W, and the cutting speed is set within the range of 200mm / s-500mm / s. Utilizing the high energy density of the laser beam, the fiber ends are heated and melted while the fabric fibers are cut, and then cooled rapidly. This creates a closed micro-melted edge on the edges of the cut pieces of each part of the polo shirt, completing the micro-melted edge sealing process. This provides a physical basis for avoiding fiber scattering caused by the impact of high-pressure airflow in the subsequent process.

[0024] S2. Subsequently, reactive moisture-curing polyurethane liquid adhesive in a heated and molten state is applied to the splicing edges of the various polo shirt pieces after micro-melting and edge sealing. Specifically, according to the mechanical performance requirements of different parts of the polo shirt, high-density continuous linear adhesive dots are applied to the collar and placket areas of the various polo shirt pieces, while micro-droplet matrix adhesive dots are applied to the armhole, shoulder seam, and side seam areas of the various polo shirt pieces to obtain adhesive-coated pieces. The reactive moisture-curing polyurethane adhesive in a heated and molten state is then applied... In the process of applying urethane liquid adhesive, the heating temperature of the dispensing equipment is set to 95℃-130℃. In high-density continuous linear dispensing, the width of a single adhesive line is set to 1.5mm-3.0mm, and the amount of adhesive applied is controlled at 30g / m²-50g / m². For microdroplet matrix dispensing, a honeycomb microdroplet matrix dispensing method is used, with the diameter of a single droplet set to 0.3mm-0.8mm, the center-to-center distance between adjacent droplets set to 0.5mm-1.5mm, and the amount of adhesive applied controlled at 10g / m²-25g / m². Specifically, the cut pieces of each component of the POLO shirt that have undergone micro-melting edge sealing are transferred to the dispensing platform. The CNC automatic dispensing system is then activated, and the heating temperature of the dispensing equipment is set to 95℃-130℃. This transforms the reactive moisture-curing polyurethane liquid adhesive within the system into a flowable, sprayable, heated, and molten state. Subsequently, the differentiated dispensing program is invoked through the control system. For the neckline and placket areas, high-density continuous linear adhesive application is used. The parameters are set as follows: the width of a single adhesive line is 1.5mm-3.0mm, and the amount of adhesive applied is controlled at 30g / m²-50g / m². The continuous adhesive lines formed under these parameters can provide high local rigidity and support for the neckline and placket areas after subsequent curing. For the armhole, shoulder seam, and side seam areas, a honeycomb micro-droplet matrix dispensing method is used. The diameter of a single droplet is set to 0.3mm-0.8mm, the center-to-center distance between adjacent droplets is 0.5mm-1.5mm, and the amount of adhesive is controlled at 10g / m²-25g / m². This discretely distributed droplet shape leaves non-adhesive gaps between the dots after the adhesive has cured. When the fabric is stretched, the adhesive dots can move synchronously with the fabric fiber mesh.

[0025] S3. Then, the adhesive-coated cut pieces are assembled and placed on the outside of a 3D porous bionic mold with evenly distributed micropores on the surface, according to the three-dimensional structure of the polo shirt. The air extraction system inside the 3D porous bionic mold is activated to establish an initial negative pressure, so that the edges of the adhesive-coated cut pieces adhere to the surface of the 3D porous bionic mold, forming a three-dimensional assembled state. The pore diameter of the micropores on the surface of the 3D porous bionic mold ranges from 0.5mm to 2.0mm, and the pore density is 5 pores / cm² to 20 pores / cm². During the process of establishing the initial negative pressure, the value of the initial negative pressure is set to -50kPa to -80kPa and maintained for 3s to 8s. Specifically, a 3D porous bionic mold is prepared. The external shape of the mold matches the three-dimensional outline of the polo shirt to be formed, and micropores are evenly distributed on its surface. The pore diameter ranges from 0.5mm to 2.0mm, and the pore density is 5 pores / cm² to 20 pores / cm². The adhesive-coated cut pieces obtained in step S2 are sequentially placed on the outside of the 3D porous bionic mold according to the structural relationship of the front piece, back piece, sleeve piece, etc., and the glued splicing edges overlap in pairs. Then, the vacuum generating system connected to the internal air circuit of the mold is activated to establish an initial negative pressure. The value of the initial negative pressure is set to -50kPa to -80kPa and maintained for 3s-8s. Under this pressure difference, the cut piece is uniformly compressed by the external atmosphere, and the splicing edge is tightly attached to the mold surface, forming a three-dimensional splicing state without creases.

[0026] S4. While maintaining the three-dimensional assembly state, pulsed high-temperature water vapor is sprayed onto the assembly edges through micropores on the surface of the 3D porous biomimetic mold. Vacuum negative pressure and micro-positive pressure steam pulses are alternately executed at a set frequency, driving the reactive moisture-curing polyurethane liquid adhesive sandwiched between the assembly edges to undergo dynamic penetration and water vapor cross-linking reaction, resulting in a cross-linked POLO shirt semi-finished product. During the pulsed high-temperature water vapor spraying process, the temperature of the pulsed high-temperature water vapor is set to 110℃-140℃; the pressure range of the micro-positive pressure steam pulse is 10kPa-30kPa, and the set frequency is 0.2Hz-0.5Hz; the entire process of alternating vacuum negative pressure and micro-positive pressure steam pulses is executed for a total of 3-8 alternating cycles. Specifically, while maintaining the initial negative pressure adsorption state of -50kPa to -80kPa, the gas-liquid phase change control program inside the mold is activated. Through the micropores on the surface of the mold, pulsed high-temperature water vapor is sprayed in the reverse direction into the fabric at the splicing edge. During this process, the temperature of the pulsed high-temperature water vapor is set to 110℃-140℃. At the moment of spraying, the micropores on the surface of the mold are transformed into a micro-positive pressure state. The pressure range of the micro-positive pressure steam pulse is 10kPa-30kPa. Simultaneously, the air circuit system is controlled to perform alternating cyclic operation at a set frequency of 0.2Hz-0.5Hz, that is, the "vacuum negative pressure and micro positive pressure steam pulse" is switched every 2s-5s. The whole process is executed for 3-8 alternating cycles. The principle is that the alternating pressure field of the cycle causes the liquid glue sandwiched between the two layers of fabric to produce microscopic peristaltic extrusion. The glue is forced into the microscopic pores of the fabric fibers to achieve dynamic penetration. The high temperature water vapor introduced at the same time directly provides the moisture and heat energy required for the cross-linking reaction of isocyanate groups, so that the glue completes the chemical network cross-linking in a three-dimensional penetration state, thereby obtaining the cross-linked POLO shirt semi-finished product.

[0027] S5. After the water-vapor crosslinking reaction is completed, stop spraying pulsed high-temperature water vapor, switch the internal air path of the 3D porous bionic mold to a high-intensity vacuum negative pressure state, remove the moisture from the crosslinked POLO shirt semi-finished product and cool and shape it to obtain an integrated POLO shirt. Return the pressure inside the 3D porous bionic mold to normal pressure, demold the integrated POLO shirt from the 3D porous bionic mold, and finally obtain a seamless elastic pressure-bonded integrated POLO shirt. Under the high-intensity vacuum negative pressure state, the negative pressure value is set to -90kPa to -98kPa, and the extraction time is 5s-15s. Before demolding the integrated POLO shirt from the 3D porous bionic mold, the time to restore the pressure inside the 3D porous bionic mold to normal pressure is controlled within 1s-3s.

[0028] Specifically, once the alternating cycle program is completed, i.e. the water-vapor crosslinking reaction is finished, the high-temperature water vapor generator is immediately shut off. Within 0.5 seconds, the internal air path of the 3D porous bionic mold is switched to a high-intensity vacuum negative pressure state. The negative pressure value of the high-intensity vacuum negative pressure state is set to -90kPa to -98kPa, and this state is maintained for 5-15 seconds. Under this extremely low pressure environment, the moisture remaining in the crosslinked POLO shirt semi-finished product quickly vaporizes and is extracted from the mold. At the same time, the high-speed flowing air carries away the heat generated by the crosslinking reaction, causing the polyurethane macromolecular chain segments to freeze, completing the cooling and shaping of the structure, and finally obtaining a structurally stable one-piece molded POLO shirt. Then, the vacuum system is shut off, and the pressure relief valve of the air passage inside the mold is opened. The time for restoring the pressure inside the 3D porous bionic mold to normal pressure is controlled within 1-3 seconds. After the internal and external air pressures are balanced, the adsorption force of the mold on the fabric is released. The operator or robotic arm peels the one-piece molded polo shirt off the mold as a whole. After collection and sorting, a seamless elastic pressure-bonded one-piece molded polo shirt with all parts connected by glue and no sewing thread marks on the surface is obtained.

[0029] To demonstrate the advantages of this invention in terms of elastic smoothness, the following embodiments and comparative examples are designed: Example 1: A seamless elastic heat-sealed one-piece molded POLO shirt prepared according to the above steps; Comparative Example 1: Compared with Example 1, the difference is that in the reactive moisture-curing polyurethane liquid adhesive component, the mass percentage of the isocyanate-terminated polyurethane prepolymer is 80.0 wt% (higher than the upper limit of 70.0 wt%), and the mass percentage of thermoplastic polyurethane resin is reduced accordingly to make up the difference, while the rest are the same. Comparative Example 2: Compared with Example 1, the difference is that: instead of using reactive moisture-curing polyurethane liquid adhesive for dispensing, conventional solid TPU hot melt adhesive tape was used to sandwich between the edges of the cut pieces and then pressed together using a traditional 2D high-temperature flatbed press. All other aspects are the same. Comparative Example 3: Compared with Example 1, the difference is that in step S2, differentiated dispensing was not performed, but high-density continuous linear dispensing was uniformly performed on all areas (including the neckline area, placket area, armhole, shoulder seam and side seam areas), and the rest were the same; Comparative Example 4: Compared with Example 1, the difference is that in step S3, the 3D porous bionic mold and initial negative pressure positioning were not used. Instead, the adhesive-coated cut pieces were laid flat on a 2D flat worktable for assembly, and downward mechanical pressure was applied to make them fit together. All other aspects are the same. Comparative Example 5: Compared with Example 1, the difference is that step S5 is omitted. That is, after the water vapor crosslinking reaction in step S4, the operation of switching to a high-intensity vacuum negative pressure state to remove moisture and cool down for shaping is not performed. Instead, the internal pressure of the mold is directly restored to normal pressure for demolding. All other aspects are the same.

[0030] The following test experiment is now prepared: 1. Elastic elongation test of the seam area (side seam) (1) Experimental instruments and environment An electronic universal testing machine (equipped with a wide-mouth fabric flat fixture) was used. The testing environment was set at a temperature of 20±2°C and a relative humidity of [missing information]. Standard atmospheric conditions.

[0031] (2) Experimental steps Sample preparation: Rectangular samples were cut from the finished polo shirts of Examples 1, Comparative Examples 1, 2, and 3 after being demolded and left to stand for 24 hours, along the direction perpendicular to the side seam. The sample dimensions were 150 mm in length and 50 mm in width, ensuring that the adhesive line of the side seam was located in the exact center of the sample length. Five parallel samples were prepared for each group. Initial gauge length setting: Draw a mark line on each side of the side seam of the specimen, and the initial distance between the two mark lines is... Set to 50mm; Tensile test: Clamp the specimen at both ends in the upper and lower clamps of the universal testing machine. Set the tensile speed to 100 mm / min, start the testing machine to apply a tensile load to the specimen, and when the load reaches 15 N, maintain this tensile state for 1 minute. Record the tensile length between the two marked lines at this time. ; Recovery Test: Unload the load, remove the sample from the fixture, lay it flat and let it stand for 30 minutes under standard conditions, then measure the remaining length between the two marked lines. ; Data calculation: Elongation at constant load (%) ; Elastic recovery rate (%) = ; The arithmetic mean of five parallel samples was taken as the final test result for the group.

[0032] The experimental data are shown in the table below:

[0033] 2. Garment flatness (3D shaping effect) and dimensional stability evaluation test (1) Experimental instruments and environment It adopts standard men's / women's 3D human body mapping model (mannequin), constant temperature and humidity suspension chamber, and high-precision flexible distance measuring tape.

[0034] (2) Experimental steps Flatness (number of dead creases) visual assessment: The POLO shirt samples that have just been demolded in Example 1, Comparative Example 2, Comparative Example 4, and Comparative Example 5 were immediately placed on a standard 3D human body model of the matching size and the placket was fastened. Three professional inspectors independently observed the armhole (three-dimensional curved transition area under the armpit) and shoulder seam area of ​​the sample garment under standard D65 lighting. The number of fixed creases (dead creases) with a length of more than 1cm caused by flat pressure or poor fit was recorded, and the average of the number recorded by the three inspectors was taken (rounded to the nearest integer).

[0035] Dimensional stability (shrinkage rate) test: Initial size measurement: Within 3 minutes of demolding the sample garment, while it is laid flat naturally, use a flexible measuring tape to measure the precise length of the left seam of the sample garment, and record it as the initial length. ; Environmental setting: Hang the measured sample garment on a wide-shouldered hanger in a temperature-controlled environment. ℃, relative humidity In a constant temperature and humidity chamber, it is left to stand without stress for 24 hours; Final size measurement: After the resting time is over, lay the sample garment flat again and measure the precise length of the same side seam area. Record this as the final length. ; Data calculation: Size shrinkage rate (%) Three sample garments were tested in each group, and the arithmetic mean was taken.

[0036] The experimental data are shown in the table below:

[0037] Combining the experimental data from the above-mentioned tests on the elastic elongation rate of the seam area and the evaluation of the garment's flatness and dimensional stability, it can be clearly verified that the core mechanism advantages of this invention in differentiated adhesive application and three-dimensional curing molding are evident. From the elastic performance data, Example 1 exhibits extremely high constant load elongation and elastic recovery rate, while the comparative examples using traditional solid hot melt adhesive film and continuous linear dispensing all show severe elasticity loss. This significant difference fully demonstrates the scientific nature of the honeycomb microdroplet matrix dispensing process used in high-activity areas such as side seams in this invention. The microdroplet matrix arrangement allows sufficient physical gaps to be reserved between droplets after the reactive moisture-curing polyurethane liquid adhesive has cured. When the fabric is stretched by external force, these independent adhesive dots can undergo synchronous three-dimensional displacement with the fiber mesh of the high-elastic knitted fabric, thereby completely breaking the mechanical locking of the traditional continuous adhesive strip to the slippage of the fabric yarn and perfectly preserving the dynamic high elasticity of the garment. In terms of garment flatness and three-dimensional shaping, Example 1 did not produce any dead creases in the complex three-dimensional curved transition areas such as the armpits and shoulder seams. In contrast, the comparison model, which relies on traditional two-dimensional flat ironing or flat physical pressing, produced a large number of irreversible fixed creases. Forcing the flat adhesive-coated cut pieces onto a two-dimensional workbench with heavy pressure will inevitably lead to excess fabric accumulating and folding in certain areas. This invention uses a 3D porous bionic mold that matches the ergonomic pattern. By establishing an initial negative pressure inside the mold, the external atmospheric pressure is used to evenly and smoothly adsorb and adhere the fabric to the three-dimensional curved surface. This completely eliminates the mechanical wrinkles that are easily generated by 2D ironing from a physical space perspective, achieving truly seamless three-dimensional splicing. The difference in dimensional shrinkage rate profoundly reveals the locking mechanism of the instantaneous high-vacuum dehydration and setting process in the thermophysical dimension. The dimensional shrinkage rate of Example 1 is extremely low, while the comparative example, which lacks this cooling dehydration and setting step, experienced severe shrinkage deformation after standing. In the alternating negative pressure and pulsed steam coupling crosslinking stage, high-temperature water vapor is forcibly injected into the gap between the fabric and the adhesive to drive a rapid reaction. If the demolding is performed directly after the crosslinking is completed, the free water remaining inside the fiber and the latent heat accumulated by the chemical reaction will cause the polyurethane macromolecular chain segments to continue to undergo slow post-curing and internal stress release after demolding, thereby causing the garment size to shrink. This invention, by instantly switching to a high-intensity vacuum negative pressure state, uses a huge air pressure difference to forcibly vaporize and remove the water in seconds. At the same time, the high-speed vacuum negative pressure airflow quickly removes the heat, causing the polyurethane macromolecular chain segments to "freeze" instantly and lose fluidity, thereby completely locking the three-dimensional composite structure of the fabric and the adhesive, ensuring the absolute stability of the garment size after it leaves the factory.

[0038] In summary, this invention provides a seamless elastic pressure-sealed one-piece molding process for polo shirts. By applying reactive moisture-curing polyurethane liquid adhesive to the splicing edges of polo shirt pieces after micro-melt sealing, and innovatively employing a differentiated dynamic dispensing process, it effectively solves the technical pain points of traditional solid hot melt adhesive films causing localized stiffness and loss of elasticity in garments. The high-density continuous linear dispensing applied to the collar and placket areas of the polo shirt provides excellent localized natural stiffness and structural rigidity without traditional lining. The micro-droplet matrix dispensing applied to the armholes, shoulder seams, and side seams forms independent discrete adhesive dots after curing. This allows the adhesive dots to undergo three-dimensional displacement synchronously with the fiber mesh when the high-elastic knitted fabric is stretched, thus perfectly preserving the original high elasticity and breathable micropores of the fabric, significantly improving wearing comfort. Furthermore, by introducing an instantaneous high-intensity vacuum dehydration and shaping process after the water vapor crosslinking reaction, it effectively overcomes the problem of post-curing shrinkage and deformation caused by residual moisture and latent heat after garment demolding. By stopping the steam injection and instantly switching the internal air path of the mold to a high-intensity vacuum negative pressure state, the unreacted free moisture in the fabric and glue seams can be forcibly vaporized and extracted in a very short time. At the same time, the high-speed flow of vacuum negative pressure airflow quickly removes the latent heat generated by chemical cross-linking, causing the polyurethane macromolecular chain segments to instantly lose fluidity and produce a "freezing" effect. This second-level thermophysical locking mechanism completely fixes the three-dimensional composite structure of the fabric and glue, giving the POLO shirt excellent factory size stability and lasting flatness.

[0039] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A manufacturing process for seamless elastic heat-sealing one-piece molded polo shirts, characterized in that, Includes the following steps: S1. First, cut the high-elastic knitted fabric into pieces for each part of the POLO shirt, and then perform micro-melting edge sealing on the edges of each piece of the POLO shirt. S2. Subsequently, a reactive, moisture-curing polyurethane liquid adhesive in a heated and molten state is applied to the splicing edges of the polo shirt pieces after micro-melting edge sealing treatment. According to the mechanical performance requirements of different parts of the polo shirt, high-density continuous linear adhesive is applied to the collar and placket areas of the polo shirt pieces, and micro-droplet matrix adhesive is applied to the armhole, shoulder seam, and side seam areas of the polo shirt pieces to obtain adhesive-coated pieces. S3. Then, the adhesive-coated cut pieces are assembled according to the three-dimensional structure of the polo shirt and placed on the outside of the 3D porous bionic mold with micropores evenly distributed on the surface. The air extraction system inside the 3D porous bionic mold is activated to establish an initial negative pressure, so that the splicing edges of the adhesive-coated cut pieces are adsorbed and attached to the surface of the 3D porous bionic mold, forming a three-dimensional splicing state. S4. While maintaining the three-dimensional assembly state, pulsed high-temperature water vapor is sprayed onto the assembly edge through the micropores on the surface of the 3D porous biomimetic mold, and vacuum negative pressure and micro positive pressure steam pulses are alternately executed at a set frequency to drive the reactive moisture-curing polyurethane liquid adhesive sandwiched between the assembly edges to undergo dynamic penetration and water vapor cross-linking reaction, thereby obtaining the cross-linked POLO shirt semi-finished product. S5. After the water-vapor crosslinking reaction is completed, stop spraying the pulsed high-temperature water vapor, switch the internal air path of the 3D porous bionic mold to a high-intensity vacuum negative pressure state, remove the moisture from the crosslinked POLO shirt semi-finished product and cool and shape it to obtain an integrated POLO shirt, restore the pressure inside the 3D porous bionic mold to normal pressure, demold the integrated POLO shirt from the 3D porous bionic mold, and finally obtain a seamless elastic pressure-bonded integrated POLO shirt.

2. The manufacturing process for a seamless elastic heat-sealed one-piece molded POLO shirt according to claim 1, characterized in that, In the process of cutting high-elastic knitted fabric into polo shirt pieces, a carbon dioxide laser cutting device is used for cutting and micro-melting edge sealing. The cutting power setting range of the carbon dioxide laser cutting device is 35W-85W, and the cutting speed setting range is 200mm / s-500mm / s.

3. The manufacturing process for a seamless elastic heat-sealed one-piece molded POLO shirt according to claim 1, characterized in that, During the application of the reactive moisture-curing polyurethane liquid adhesive in a heated and molten state, the heating temperature of the adhesive application equipment is set to 95℃-130℃.

4. The manufacturing process for a seamless elastic heat-sealed one-piece molded POLO shirt according to claim 3, characterized in that, In the high-density continuous linear dispensing, the width of a single dispensing line is set to 1.5mm-3.0mm, and the amount of dispensing is controlled at 30g / m²-50g / m²; the microdroplet matrix dispensing is a honeycomb microdroplet matrix dispensing, the diameter of a single droplet is set to 0.3mm-0.8mm, the center-to-center distance between adjacent droplets is set to 0.5mm-1.5mm, and the amount of dispensing is controlled at 10g / m²-25g / m².

5. The manufacturing process for a seamless elastic heat-sealed one-piece molded POLO shirt according to claim 1, characterized in that, The pore diameter of the micropores on the surface of the 3D porous biomimetic mold ranges from 0.5mm to 2.0mm, and the pore density is 5 pores / cm² to 20 pores / cm². During the process of establishing the initial negative pressure, the value of the initial negative pressure is set to -50kPa to -80kPa and maintained for 3s to 8s.

6. The manufacturing process for a seamless elastic heat-sealed one-piece molded POLO shirt according to claim 1, characterized in that, During the process of injecting pulsed high-temperature water vapor, the temperature of the pulsed high-temperature water vapor is set to 110℃-140℃; the pressure range of the micro-positive pressure steam pulse is 10kPa-30kPa.

7. The manufacturing process for a seamless elastic heat-sealed one-piece molded POLO shirt according to claim 6, characterized in that, The set frequency is 0.2Hz-0.5Hz; the entire process of alternating vacuum negative pressure and micro positive pressure steam pulse is executed for a total of 3-8 alternating cycles.

8. The manufacturing process for a seamless elastic pressure-sealed one-piece molded POLO shirt according to claim 1, characterized in that, Under the high-intensity vacuum negative pressure state, the negative pressure value of the high-intensity vacuum negative pressure state is set to -90kPa to -98kPa, and the extraction time under this state is 5s-15s.

9. The manufacturing process for a seamless elastic pressure-sealed one-piece molded POLO shirt according to claim 1, characterized in that, Before demolding the one-piece molded polo shirt from the 3D porous bionic mold, the time for restoring the pressure inside the 3D porous bionic mold to normal pressure is controlled within 1s-3s.

10. A seamless, elastic, one-piece molded polo shirt, characterized in that, According to any one of claims 1-9, a seamless elastic pressure-sealed one-piece molding process for a POLO shirt is provided, wherein the POLO shirt does not contain sewing threads, and its splicing edges are connected by a reactive moisture-curing polyurethane liquid adhesive. The raw material composition and mass percentage of the reactive moisture-curing polyurethane liquid adhesive before curing include: Isocyanate-terminated polyurethane prepolymer: 55.0wt%-70.0wt%; Thermoplastic polyurethane resin: 15.0wt%-25.0wt%; Tackifying resin: 5.0wt%-12.0wt%; Rheology modifier: 1.5wt%-5.0wt%; Organotin catalysts: 0.1wt%-0.5wt%; Antioxidants and UV absorbers: 0.4wt%-1.5wt%.

Images