Artificial Turf using Double Coating Foaming Method and Manufacturing Method thereof

Abstract

The present invention relates to an artificial turf and a method for manufacturing the same, which utilizes a double-coating foaming method capable of fixing yarns and reinforcing elasticity, by additionally coating a foam sheet on top of the artificial turf yarns and simultaneously forming a shock-absorbing pad structure that blocks the inflow of silica sand through a double-woven structure. Specifically, in the artificial turf utilizing the double-coating foaming method, inner yarns are woven into a first foam sheet, and a blocking pad is provided that is bonded to the upper surface of the inner yarns to block the inflow of silica sand and filler, and an outer yarn is woven through the blocking pad to connect to the first foam sheet, and a double coating layer is provided that fixes the outer yarns and forms an elastic layer on the lower surface of the first foam sheet.

Description

Technology Field

[0001] The present invention relates to an artificial turf using a double-coating foaming method and a method for manufacturing the same. More specifically, the invention relates to an artificial turf using a double-coating foaming method and a method for manufacturing the same, wherein a second base sheet is laminated on the upper surface of a base pile layer in which a crimp or mono yarn is woven on a first base sheet to form an independent shock-absorbing pad structure that blocks the inflow of silica sand, and a first coating that strengthens the yarn pull-out force through an upper coating method and a second coating that maximizes shock absorption by forming a foaming layer 0.5 to 2 cm high are performed in stages, thereby preventing a decrease in elasticity due to compaction of silica sand even during long-term use and significantly reducing the risk of injury to players, while maintaining excellent cushioning performance without the need for a separate pad installation. Background Technology

[0003] In general, in the fields of modern sports and landscaping, artificial turf has established itself as an essential flooring material to overcome the weather limitations and maintenance difficulties of natural grass and to provide uniform performance throughout all four seasons. Technically, it is primarily constructed by tufting artificial yarns onto a polypropylene (PP) or polyethylene (PE) substrate, and then spreading silica sand and elastic fillers (such as rubber chips) between them to distribute the load from the ground and protect the ankle and knee joints of the players.

[0004] Beyond these basic functions, various advanced technologies have been developed over the years to impart high levels of cushioning to artificial turf systems in order to maximize injury prevention for athletes and extend product lifespan. Representative examples include the pad-separation installation method, which involves installing a separate shock-absorbing pad beneath the artificial turf mat, and the development of technologies that regulate shock absorption (G-max) by overlapping and spraying large amounts of elastic filler between the fibers.

[0005] However, existing technologies cause a 'compaction' phenomenon during long-term use, where silica sand and filler scattered on the surface sink to the bottom and harden due to load and footing. This results in a rapid deterioration of the initially designed cushioning performance and causes the ground to become as hard as concrete. Furthermore, the method of installing separate pads complicates the construction process, increasing construction time and costs. Additionally, conventional coating methods that apply resin from the bottom have continuously raised issues regarding insufficient pull-out strength, where the yarn easily detaches in rough playing environments because the resin does not sufficiently penetrate into the yarn.

[0006] Therefore, the present invention forms independent voids within the foundation pile layer and seals them with a blocking pad to completely block the inflow of silica sand, while significantly improving durability through a double coating method with separated functions. This possesses very high industrial value in that it goes beyond merely enhancing technical perfection; it improves construction cost-effectiveness and provides the best safe playing environment for athletes by establishing an integrated system that maintains permanent elasticity without the need for separate pad installation. Prior art literature

[0008] (Patent Document 0001) KR 10-2316796 B1 (October 19, 2021) The problem to be solved

[0009] The present invention has been devised to solve the above-mentioned problems, and its purpose is to provide an artificial turf using a double-coating foaming method and a method for manufacturing the same, which can provide an optimal vertical load distribution mechanism to prevent injury to players by separating functions into a primary coating for fixing the yarn and a secondary foaming coating that forms micro-bubbles, thereby constructing an integrated shock-absorbing pad structure that maintains permanent cushioning performance by forming independent internal voids between a first foaming sheet and a second foaming sheet, and securing unrivaled tensile strength by allowing the coating resin to penetrate deeply into the yarn root portion through an upper coating method. means of solving the problem

[0011] The artificial turf using the double-coating foaming method of the present invention for achieving the above-mentioned purpose comprises: an inner yarn (120) woven into the first base sheet (110) such that a yarn protrusion (121) protruding outwardly is formed on the rear surface of the first base sheet (110); a second base sheet (210) is laminated onto the upper surface of the inner yarn (120) and then joined by heat fusion or sewing to form a void layer; the second base sheet (210) is a blocking pad (200) that blocks silica sand and filler from flowing into the void layer; and the outer yarn (300) is woven to penetrate the second base sheet (210) and connect to the first base sheet (110), wherein at the contact point between the root of the outer yarn (300) and the rear surface of the first base sheet (110), one selected from SBR latex, polyurethane (PU), or PEVA resin The first coating layer (410) is formed by a top coating method in which resin penetrates by gravity to fix the inner yarn (120) and outer yarn (300) to the first base sheet (110), or by a heat fusion press method in which PE powder is applied to the first base sheet (110) and then passed through a compression roller (800) to fix the inner yarn (120) and outer yarn (300) to the first base sheet (110), and a second coating layer (420) having a foamed structure that absorbs shock is formed below the first coating layer (410).

[0012] In addition, the first base sheet (110) is made of PP or PET material of a predetermined weight, and the inner yarn (120) is woven into the first base sheet (110) at a height of 5 to 25 mm and is characterized by having a weight of 3,000 to 6,000 DTEX.

[0013] Additionally, the blocking pad (200) is characterized by being joined using one of the following methods: a heat fusion method formed by applying 50 to 100 g of PE powder to the upper surface of the second foam sheet (210) and the inner yarn (120) and passing it through a press at 180 to 200°C, or a sewing method in which the second foam sheet (210) is sewn to the first foam sheet (110) at intervals of 5 to 200 mm.

[0014] In addition, the outer yarn (300) is characterized by a mono yarn with a weight of 6,000 to 15,000 DTEX being woven to a height of 20 to 65 mm on the upper part of the second base sheet (210), and being sewn through the second base sheet (210) to the first base sheet (110) to secure drawing strength.

[0015] delete

[0016] delete

[0017] In addition, the second coating layer (420) is characterized by applying a foaming liquid formed from one selected from PE, PU, ​​or SBR latex to a height of 0.5 to 2 cm on the upper surface of the first coating layer (410), and by pressing with a roller 60 seconds after the foaming starts, the foaming liquid is partially applied in a diamond or embossed pattern to form a horizontal drainage passage.

[0018] In addition, the method for manufacturing artificial turf using the double-coating foaming method of the present invention for achieving the above-mentioned purpose comprises: a base pile layer weaving step (S1100) in which inner yarns (120) are woven on the first base sheet (110) so that yarn protrusions (121) protruding outwardly are formed on the rear surface of the first base sheet (110); and a blocking pad joining step (S1200) in which, after the base pile layer weaving step (S1100), a second base sheet (210) is laminated on the upper surface of the inner yarns (120) and then joined by heat fusion or sewing to form a void layer, and a blocking pad (200) is formed to block silica sand and filler from flowing into the void layer. After the above blocking pad joining step (S1200), the outer yarn weaving step (S1300) in which the outer yarn (300) is woven over the second base sheet (210) and sewn through the second base sheet (210) to the first base sheet (110); and after the outer yarn weaving step (S1300), the first coating step (S1410) in which a coating liquid is directly applied to the root of the outer yarn (300) and the contact point on the back of the first base sheet (110) or PE powder is fused to form a first coating layer (410), and the second coating step (S1420) in which a second coating layer (420) having a foamed structure that absorbs shock is formed on the lower part of the first coating layer (410) are formed.

[0019] In addition, the second coating step (S1420) is characterized by applying a foaming liquid and, starting 60 seconds after the foaming begins, compressing it through a roller to correct the foaming concentration and height and forming an embossing pattern.

[0020] In addition, it is characterized by further including a cooling step (S1500) in which, after the above double coating step (S1400), the temperature is lowered by 20°C or more while passing through a cooling tunnel to fix the foam structure. Effects of the invention

[0022] The present invention fundamentally blocks the inflow of silica sand and filler material into the lower part of the blocking pad, thereby preserving the cushioning performance of the lower void layer without change even after long-term use.

[0023] The present invention can prevent joint injuries to users through a multi-stage shock absorption structure in which an air cushion of the base pile layer and a foamed elastic layer of the double coating layer are combined.

[0024] The present invention allows the primary coating of the top coating method to penetrate deeply to the yarn root contact point, and the through-weaving structure enhances the sense of unity, thereby preventing yarn shedding even in rough competition environments.

[0025] The present invention allows for rapid drainage without water accumulation even during rain by having an embossing or diamond pattern formed on the second coating layer function as a drainage channel.

[0026] In this invention, since the two-layer coating layer is integrated, a separate pad installation process is eliminated, thereby reducing construction costs and significantly shortening the construction period. Brief explanation of the drawing

[0028] FIG. 1 is a perspective view of artificial turf using a double-coating foaming method according to one embodiment of the present invention. FIG. 2 is a cross-sectional view of artificial turf using a double-coating foaming method according to one embodiment of the present invention. FIGS. 3 and 4 are exemplary diagrams showing the coupling of a blocking pad according to an embodiment of the present invention. FIGS. 5 and 6 are exemplary diagrams showing the formation of a first coating layer according to an embodiment of the present invention. FIG. 7 is an exemplary diagram showing the formation of a second coating layer according to an embodiment of the present invention. FIG. 8 is a flowchart of a method for manufacturing artificial turf using a double-coating foaming method according to another embodiment of the present invention. Specific details for implementing the invention

[0029] Embodiments of the present invention will be described in detail below with reference to the attached drawings. However, the present invention is not limited to these embodiments and can be modified in various forms.

[0030] In the drawings, parts unrelated to the description have been omitted to clearly and concisely explain the present invention, and the same reference numerals are used for identical or extremely similar parts throughout the specification. Additionally, in the drawings, thicknesses, widths, etc., are depicted enlarged or reduced to make the description clearer; however, the thicknesses, widths, etc., of the present invention are not limited to those depicted in the drawings.

[0031] And when any part of the specification is described as "including" another part, unless specifically stated otherwise, it does not exclude other parts and may include additional parts.

[0033] Hereinafter, an artificial turf using a double-coating foaming method and a method for manufacturing the same will be described in detail with reference to the attached drawings.

[0035] FIG. 1 is a perspective view of artificial turf using a double-coating foaming method according to one embodiment of the present invention, and FIG. 2 is a cross-sectional view of artificial turf using a double-coating foaming method according to one embodiment of the present invention.

[0036] As illustrated in FIGS. 1 and 2, the artificial turf using the double-coating foaming method according to one embodiment of the present invention forms a shock-absorbing pad structure that blocks the inflow of silica sand through a double-weaving structure while additionally coating a foam sheet on the upper yarn of the artificial turf, and the double-coating method is applied to fix the yarn and enhance elasticity.

[0037] Conventional artificial turf has installed a separate shock-absorbing pad underneath or scattered silica sand and elastic infill between the fibers to mitigate impact from the ground. However, the installation of a separate pad causes construction time to be extended and costs to increase, and the infill method has a problem in that the initially designed shock-absorbing performance rapidly deteriorates due to compaction caused by the compaction of the silica sand during long-term use.

[0038] On the other hand, the artificial turf using the double-coating foaming method of the present invention forms a physical barrier that blocks the inflow of silica sand inside, thereby constructing a shock-absorbing pad layer integrally, and provides durability and safety that can withstand even during games by separating the yarn binding and shock absorption functions through the double-coating method. In this artificial turf using the double-coating foaming method, inner yarn (120) is woven into a first base sheet (110), a blocking pad (200) that is bonded to the upper surface of the inner yarn (120) to block the inflow of silica sand and filler, an outer yarn (300) that penetrates the blocking pad (200) and is connected to the first base sheet (110), and a double-coating layer (400) that fixes the outer yarn (300) and forms an elastic layer on the lower surface of the first base sheet (110) are formed.

[0039] The first base sheet (110) is formed on the upper part of the ground to secure a buffer space and is made of PP or PET material of a predetermined weight, and the inner yarn (120) is woven into the first base sheet (110) at a height of 5 to 25 mm and has a weight of 3,000 to 6,000 DTEX.

[0040] At this time, the first foam sheet (110) is preferably composed of PP (polypropylene) or PET (polyester) material with a weight of 100 to 200 g, which determines the mechanical properties and shape stability of the entire mat.

[0041] To explain this in detail, if the weight of the first base sheet (110) is less than 100g, the force holding the yarn during the tufting process is insufficient, which may cause the yarn to detach during long-term use, resulting in reduced pulling power and localized damage. Conversely, if the weight exceeds 200g, the first base sheet (110) becomes excessively stiff, which reduces flexibility and causes adverse effects such as reduced winding efficiency during the manufacturing process.

[0042] On this first base sheet (110), inner yarn (120) with a weight of 3,000 to 6,000 DTEX is woven to a height of 5 to 25 mm to form an elastic void at the bottom, and the inner yarn (120) is woven into the first base sheet (110) that is in direct contact with the ground to create a void layer that is not exposed to the outside. At this time, on the back surface of the first base sheet (110), a yarn protrusion (121) that protrudes outward is formed as the inner yarn (120) is tufted.

[0043] Here, if the fineness of the inner yarn (120) is less than 3,000 DTEX, the yarn is too thin and cannot withstand the load of silica sand and filler scattered from above, causing it to collapse easily and lose its inherent cushioning function of the pore layer; if it exceeds 6,000 DTEX, the density of the yarn becomes too high, reducing the air content within the pores and increasing the total weight of the product excessively, thereby hindering ease of construction. Additionally, if the weaving height is less than 5mm, the volume of the formed pores is small, making it difficult to expect a substantial shock absorption effect; and if it exceeds 25mm, the self-standing ability of the yarn decreases, causing it to bend to the side, making it difficult to maintain a uniform pore height.

[0044] Accordingly, the first base sheet (110) is woven using a tougher to achieve a high density of yarn weight of 1 to 3 kg / m², thereby being linked with the upper blocking pad (200) to fundamentally block silica sand penetration and act as a buffer against the ground.

[0045] The second air bubble sheet (210) is a blocking pad (200) that blocks silica sand and filler from flowing into the void layer, and is attached to the upper surface of the inner yarn (120) to perform the role of a physical barrier that fundamentally blocks the inflow of silica sand and filler. At this time, the second air bubble sheet (210) is fixed by being laminated on the upper surface of the inner yarn (120) to seal the internal void, and preferably, a second air bubble sheet (210) with a weight of 100 to 200 g is fixed.

[0046] Here, if the weight of the second foam sheet (210) is less than 100g, it cannot withstand the physical impact generated during the weaving of the outer yarn or the load of the upper filler, and there is a risk that the partition structure will be damaged and silica sand will enter, and conversely, if it exceeds 200g, the flexibility of the entire artificial turf will decrease, resulting in reduced workability and increased manufacturing costs.

[0047] And as a method of bonding the second filament (210) to the upper surface of the inner yarn (120), either a heat fusion method or a sewing method is selectively applied depending on the manufacturing environment or the material characteristics of the yarn.

[0048] First, regarding the heat fusion method with reference to FIG. 3, 50 to 100 g of PE powder is applied between the second base sheet (210) and the inner yarn (120), and then thermally integrated by passing through a press at 180 to 200°C. At this time, if the applied PE powder is less than 50 g, the interlayer bonding strength is insufficient, and the pad may separate during use; if it exceeds 100 g, the molten resin may penetrate excessively between the yarns, which may reduce flexibility. Additionally, if the press temperature is less than 180°C, the PE powder is not sufficiently melted, resulting in poor adhesion; and if it exceeds 200°C, it may cause thermal deformation of the first base sheet (110), the second base sheet (210), or the yarn, thereby reducing stability.

[0049] And, referring to FIG. 4, the sewing method involves physically joining the second base sheet (210) to the first base sheet (110) by sewing it at intervals of 5 to 200 mm. This is advantageous for ensuring stability when using materials that are susceptible to heat. If the sewing interval exceeds 20 mm, the adhesion between the first base sheet (110) and the second base sheet (210) decreases, and there is a risk that fine silica sand may penetrate into the gaps, so the interval must be precisely controlled.

[0050] Accordingly, the blocking pad (200) can maintain the initially designed shock absorption performance throughout the stadium life cycle by maintaining the internal void at the bottom formed by the inner yarn (120), which is formed from crimp yarn or mono yarn. At this time, the inner yarn (120) may be formed from crimp yarn or mono yarn, but it should be understood that it is preferably formed from crimp yarn having a certain wavy curvature rather than a straight shape.

[0051] The outer yarn (300) is woven to be exposed to the outside, penetrating the blocking pad (200) and connecting to the first base sheet (110). At this time, the outer yarn (300) is positioned on the upper part of the blocking pad (200) to form a surface where actual game activities take place, and high-strength mono yarn with a weight of 6,000 to 15,000 DTEX is woven to a height of 20 to 65 mm.

[0052] Here, if the fineness of the outer yarn (300) is less than 6,000 DTEX, the physical strength of the yarn is insufficient, so the pile may be easily worn out or cut by shear force or friction occurring in a vigorous game environment, and conversely, if it exceeds 15,000 DTEX, the yarn becomes excessively stiff, which may hinder the activities of the players. Also, if the weaving height is less than 20mm, there is insufficient space to accommodate silica sand and filler, making it difficult to secure appropriate elasticity, and if it exceeds 65mm, the yarn collapses due to its own weight, causing a decrease in appearance quality and game performance.

[0053] Additionally, the outer yarn (300) adopts a through-weaving method in which it penetrates the second base layer (210) and is directly sewn to the lowest first base layer (110).

[0054] Accordingly, the vertical bonding structure allows the coating resin to penetrate deeply to the root contact of the yarn, even though it is a multilayer foam structure, and can secure tensile strength so that the yarn is not easily pulled out.

[0055] The double coating layer (400) can secure safety by strongly fixing the outer yarn (300) to the foam sheet while simultaneously forming an elastic layer on the upper surface of the ground. At this time, the double coating layer (400) adopts an upper coating method in which resin is directly applied to the contact point where the root of the outer yarn (300) meets the back surface of the first foam sheet (110), thereby allowing the coating liquid to seep deep into the yarn binding area due to its own weight, thereby securing tensile strength. Furthermore, the double coating layer (400) goes beyond the role of an adhesive for fixing the yarn and is linked with the lower void layer, allowing for increased elastic recovery power without the need for a separate pad installation.

[0056] This double coating layer (400) is formed by applying a first coating layer (410) using an upper coating method at the contact point where the root of the outer yarn (300) and the rear surface of the first base paper (110) come into contact, and a second coating layer (420) formed by applying a foamed resin on top of the first coating layer (410) to form a shock-absorbing layer.

[0057] In addition, the first coating layer (410) secures the drawing force of the outer yarn (300) and adopts a top coating method in which resin is directly applied to the contact point where the root of the outer yarn (300) and the back surface of the first base paper (110) meet, thereby allowing the resin to penetrate into the yarn binding area by its own weight and increase the binding force. This first coating layer is formed by one of the selected methods, either a liquid coating method or a heat fusion press method, depending on the manufacturing environment or the characteristics of the raw material, to fix the yarn.

[0058] First, regarding the liquid application method with reference to FIG. 5, the first base sheet is flipped over and one selected from SBR latex, polyurethane (PU), or PEVA resin is applied through the application device (500), and then cured through the hot air processing machine (600) (Tenter). At this time, the curing temperature is precisely controlled within the range of 90 to 110°C. If the curing temperature is below 90°C, the chemical cross-linking reaction of the resin occurs insufficiently, and the adhesive strength between the yarn and the base sheet falls below the standard value, and the yarn may detach during long-term use. Also, if the temperature exceeds 110°C, the heat-sensitive artificial turf yarn (PE, etc.) may be physically deformed or the resin may be excessively cured, resulting in reduced flexibility of the entire film and a brittle state, which lowers durability.

[0059] Next, referring to FIG. 6, the heat fusion press method is a process of physically integrating by applying PE powder, which is an adhesive medium, and passing it through heated compression rollers (800). After evenly spreading 50 to 100 g of PE powder on the upper surface of the first foam sheet (110), strong pressure is applied by passing it through 2 to 4 compression rollers (800) heated to a temperature of 180 to 200°C. At this time, if the pressure temperature is less than 180°C, the PE powder is not sufficiently melted, and as a matrix to firmly hold the foam sheet and the yarn is not formed, interfacial delamination may occur. Also, if the temperature exceeds 200°C, the resin melted by the heat may spread more widely than necessary, blocking the pore layer or causing thermal degradation of the foam sheet material itself, which may reduce the tensile strength of the mat. In addition, if the number of compression rollers (800) is less than 2, it is difficult to transmit uniform pressure, so there may be partial differences in drawing force, and if it exceeds 4, the process line becomes unnecessarily long and the resilience of the yarn may be impaired.

[0060] This first coating layer secures tensile strength compared to conventional methods by concentrating the resin at the root of the yarn through an upper coating method, and can improve performance and durability by creating synergy with the second foamed coating layer.

[0061] The second coating layer is intended to improve cushioning performance on the upper surface where the first coating is completed. It is formed integrally during the artificial turf manufacturing process to provide permanent cushioning performance and can prevent knee and ankle injuries to players. At this time, referring to FIG. 7, the second coating layer is formed by applying a foaming liquid, selected from PE, PU, ​​or SBR latex, to a height of 0.5 to 2 cm on the upper surface of the first coating layer through an application device (500).

[0062] Furthermore, if the foam height is less than 0.5 cm, the amount of microbubbles is insufficient, making it difficult to expect a sufficient shock absorption effect, and technical limitations arise where impact from the ground is directly transmitted to the athlete. Additionally, if the foam height exceeds 2 cm, the foam layer becomes excessively thick, reducing shape stability and weakening the support of the upper yarn, which may result in an unstable walking sensation. The applied foaming liquid forms microbubbles over a foaming time of 1 to 3 minutes, and is compressed through rollers placed at regular intervals starting 60 seconds after the start of foaming.

[0063] Here, if the compression time is less than 60 seconds, the bubble structure may be destroyed before sufficient foaming occurs, and the cushioning performance may rapidly decrease; conversely, if the compression time is delayed too long, the resin may already begin to harden, making it difficult to precisely correct the foaming concentration and height.

[0064] Furthermore, the second coating layer is not applied to the entire upper surface but is partially applied in a diamond or embossed pattern to form horizontal drainage channels between the coating layers. This pattern structure reduces the amount of chemical resin used compared to full application while maximizing localized compressive recovery, and enables rapid drainage without water accumulation during rain, thereby supporting all-weather game operations.

[0065] The product, which has been coated and compressed by such a double coating layer (400), passes through a cooling tunnel and rapidly lowers the temperature by more than 20°C to fix and stabilize the foam structure.

[0067] FIG. 8 is a flowchart of a method for manufacturing artificial turf using a double-coating foaming method according to another embodiment of the present invention.

[0068] As illustrated in FIG. 8, the method for manufacturing artificial turf using a double-coating foaming method according to one embodiment of the present invention comprises a base pile layer weaving step (S1100) in which inner yarn (120) is woven on a first base sheet (110), a blocking pad joining step (S1200) in which a second base sheet (210) is joined to the upper surface of the inner yarn (120) to form a blocking pad (200), an outer yarn weaving step (S1300) in which outer yarn (300) is woven through the blocking pad (200), and a double coating step (S1400) in which resin is applied to the upper surface and root portion of the woven yarn and foamed.

[0069] Here, the base pile layer weaving step (S1100) is a process of constructing a lower porous layer that serves as the foundation of artificial turf, in which inner yarn (120) with a weight of 3,000 to 6,000 DTEX is tufted to a height of 5 to 25 mm onto a first base sheet (110) made of PP or PET material with a weight of 100 to 200 g. At this time, by using a 5 / 32, 3 / 16, or 5 / 16 tufting machine to weave the yarn at a high density of 1 to 3 kg / ㎡, a cushioning space is provided while withstanding the upper load.

[0070] Next, the blocking pad joining step (S1200) forms a partition to block the inflow of silica sand and filler material by laminating a second foam sheet (210) of 100 to 200g on the upper surface of the base pile layer (100), applying 50 to 100g of PE powder, and joining by selectively applying one of the heat fusion method of passing through a press at 180 to 200℃ or the sewing method of sewing at intervals of 5 to 200mm through a sewing device (700).

[0071] This blocking pad bonding step (S1200) is optimized according to the thermal properties of the material and can block silica sand by maintaining a temperature of 180°C or higher during heat fusion to induce integration between the bubble sheets.

[0072] And in the outer yarn weaving stage (S1300), high-strength monofilament yarn with an upright weight of 6,000 to 15,000 DTEX is woven to a height of 20 to 65 mm, and the outer yarn (300) penetrates the second base layer (210) and is sewn directly to the first base layer (110) at the bottom. This is to ensure that the entire mat is bound together as one despite the multi-layer structure, thereby securing tensile strength so that the yarn does not easily detach.

[0073] Additionally, the double coating step (S1400) is formed by a first coating step (S1410) in which a coating liquid is directly applied to the contact point between the root of the outer yarn (300) and the back surface of the first foam sheet (110) or PE powder is fused to strengthen the tensile strength, and a second coating step (S1420) in which, after the first coating step (S1410), a foaming liquid is applied and compressed through a roller from 60 seconds after the foaming starts to correct the foaming concentration and height and form an embossing pattern.

[0074] First, in the first coating step (S1410), SBR latex or PU resin is directly applied through an application device (500) to the contact point between the root of the outer yarn (300) and the back of the first base paper (110), or PE powder is fused to strengthen the tensile strength. At this time, the first coating is performed using an upper coating method in which the coating resin penetrates the root portion of the yarn by its own weight. If a liquid application method is selected, SBR latex, polyurethane (PU), or PEVA resin is applied through the application device (500), and then cured by passing it through a hot air processing machine (600) (Tenter) at a temperature of 90 to 110°C. If a heat fusion press method is selected, 50 to 100g of PE powder is applied, and then pressure is applied through a press at a temperature of 180 to 200°C using 2 to 4 compression rollers (800) to bond the yarn and the base paper.

[0075] Next, the second coating step (S1420), which is performed after the first coating step (S1410), involves applying a foaming liquid and, starting 60 seconds after the foaming begins, compressing it through a roller to correct the foaming concentration and height and forming an embossing pattern.

[0076] Specifically, the second coating layer (420) formed by the second coating step (S1420) is provided with a cushioning effect by applying PE, PU, ​​or SBR latex foaming liquid to a height of 0.5 to 2 cm through a coating device (500) and setting the weight to 250 to 500 g per square meter. In particular, the method of applying pressure through a roller positioned from 60 seconds after the start of foaming provides a uniform cushioning effect to the entire product by consistently adjusting the concentration and height of the foaming layer.

[0077] In addition, when the second coating step (S1420) is performed in the manner described above, the foaming liquid is partially applied in a diamond or embossed pattern to form horizontal drainage channels between the coating layers. This enables rapid drainage during rain, thereby preventing water accumulation and distributing the vertical load from the ground in multiple stages to prevent knee and ankle injuries to the athlete.

[0078] Accordingly, the double coating step (S1400) can maintain permanent cushioning performance without the need for a separate pad installation by continuously performing primary bonding and secondary foaming and compression through an upper coating method while the outer yarn (300) is woven through to the first base paper (110) in order to realize the physical composition of the double coating layer (400).

[0079] The artificial turf manufacturing method using such a double-coating foaming method involves a base pile layer weaving step (S1100), a barrier pad bonding step (S1200), a outer yarn weaving step (S1300), and a double coating step (S1400), after which a cooling step (S1500) is formed to firmly fix the foamed double coating layer (400) and ensure stability.

[0080] Here, the cooling step (S1500) is a process of physically fixing the expanded resin and foam structure by passing through a high-temperature heating tenter or coating line after the double coating step (S1400). At this time, the cooling step (S1500) is designed so that the artificial turf passes through a cooling tunnel, and the foam structure can be fixed by rapidly lowering the temperature of the product by more than 20°C inside the cooling tunnel.

[0081] To explain this in detail, the cooling step (S1500) cures the fine bubbles with a height of 0.5 to 2 cm and the diamond or embossed pattern formed in the second coating step (S1420) so that they do not collapse due to external pressure and impact. At this time, if the temperature is not sufficiently lowered to 20°C or higher during the cooling step (S1500), adhesion between film layers may occur or the drainage pattern may be distorted when the coating resin is wound while still having accelerated fluidity.

[0083] Although an artificial turf using a double-coating foaming method according to one embodiment of the present invention and a method for manufacturing the same have been described above, the concept of the present invention is not limited to the embodiments presented in this specification. Furthermore, those skilled in the art who understand the concept of the present invention may easily propose other embodiments within the scope of the same concept by adding, changing, deleting, or adding components, and such are also to be considered to fall within the scope of the concept of the present invention. Explanation of the symbols

[0085] 100: Foundation pile layer 110: First buoyancy site 120: Inner thread yarn 121: Cardiac process 200: Blocking pad 210: Second Pod 300: Outer yarn 400: Double coating layer 410: First coating layer 420: Second coating layer 500: Dispensing device 600: Hot air processing machine 700: Sewing machine 800: Compression roller S1100: Base pile layer weaving stage S1200: Blocking pad coupling step S1300: Outer yarn weaving stage S1400: Double coating step S1410: First coating step S1420: Second coating step S1500: Cooling stage

Claims

Claim 1 A void layer is formed by weaving an inner yarn (120) on the first base sheet (110) so that a yarn protrusion (121) protruding outwardly is formed on the rear surface of the first base sheet (110), and then laminating a second base sheet (210) on the upper surface of the inner yarn (120) and joining them by heat fusion or sewing; the second base sheet (210) is a blocking pad (200) that blocks silica sand and filler from flowing into the void layer, and the outer yarn (300) is woven to be connected to the first base sheet (110) by penetrating the second base sheet (210), and one resin selected from SBR latex, polyurethane (PU), or PEVA resin penetrates by gravity into the contact point between the root of the outer yarn (300) and the rear surface of the first base sheet (110) and the first base sheet (110). Artificial turf using a double coating foaming method, characterized by forming a first coating layer (410) by a top coating method that fixes the inner yarn (120) and outer yarn (300) or by a heat fusion press method that fixes the inner yarn (120) and outer yarn (300) to the first foam sheet (110) by applying PE powder and passing it through a compression roller (800), and forming a second coating layer (420) with a shock-absorbing foaming structure below the first coating layer (410). Claim 2 Artificial turf using a double-coating foaming method, characterized in that, in claim 1, the first base sheet (110) is made of PP or PET material of a predetermined weight, and the inner yarn (120) is woven into the first base sheet (110) at a height of 5 to 25 mm and has a weight of 3,000 to 6,000 DTEX. Claim 3 In paragraph 2, the blocking pad (200) is formed by a heat fusion method selected from one of the following: a method in which 50 to 100 g of PE powder is applied to the upper surface of the second foam sheet (210) and the inner yarn (120) and passed through a press at 180 to 200°C, or a sewing method in which the second foam sheet (210) is sewn to the first foam sheet (110) at intervals of 5 to 200 mm. Claim 4 In paragraph 3, the above outer yarn (300) is woven with a mono yarn weighing 6,000 to 15,000 DTEX at a height of 20 to 65 mm on the upper part of the second base sheet (210), and is sewn through the second base sheet (210) to the first base sheet (110) to secure tensile strength, thereby forming an artificial turf using a double-coating foaming method. Claim 5 delete Claim 6 delete Claim 7 Artificial turf using a double coating foaming method according to claim 1, wherein the second coating layer (420) is formed by applying a foaming liquid selected from PE, PU, ​​or SBR latex to a height of 0.5 to 2 cm on the upper surface of the first coating layer (410), and as the foaming liquid is compressed with a roller starting 60 seconds after the start of foaming, the foaming liquid is partially applied in a diamond or embossed pattern to form a horizontal drainage passage. Claim 8 A base pile layer weaving step (S1100) in which inner yarn (120) is woven on the first base sheet (110) so that yarn protrusions (121) protruding outwardly are formed on the rear surface of the first base sheet (110); a blocking pad joining step (S1200) in which, after the base pile layer weaving step (S1100), a second base sheet (210) is laminated on the upper surface of the inner yarn (120) and then joined by heat fusion or sewing to form a gap layer, and a blocking pad (200) is formed to block silica sand and filler material from entering the gap layer; and a outer yarn weaving step (S1300) in which, after the blocking pad joining step (S1200), outer yarn (300) is woven over the second base sheet (210) and sewn through the second base sheet (210) to the first base sheet (110). A method for manufacturing artificial turf using a double coating foaming method, characterized by comprising: a first coating step (S1410) in which a coating liquid is directly applied to the contact point between the root of the outer yarn (300) and the back surface of the first base paper (110) after the outer yarn weaving step (S1300) or by fusing PE powder to form a first coating layer (410); and a second coating step (S1420) in which a second coating layer (420) having a foamed structure that absorbs shock is formed on the lower part of the first coating layer (410). Claim 9 In claim 8, the second coating step (S1420) is characterized by applying a foaming liquid and, starting 60 seconds after the start of foaming, compressing with a roller to correct the foaming concentration and height and forming an embossing pattern, in a method for manufacturing artificial turf using a double-coating foaming type method. Claim 10 In claim 8, the artificial turf manufacturing method further comprises a cooling step (S1500) in which, after the double coating step (S1400), the temperature is lowered by 20°C or more while passing through a cooling tunnel to fix the foam structure.

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