Water-permeable artificial turf and method for manufacturing water-permeable artificial turf

Abstract

To provide a water-permeable artificial turf capable of suppressing the outflow of micro-plastics to the outside, and a method for manufacturing the water-permeable artificial turf.SOLUTION: A water-permeable artificial turf 10 is provided with a base layer 11 and a turf layer 12 made of turf yarn 21 raised on the surface side of the base layer 11, the base layer 11 is provided with a water-permeable layer 13 made of woven fabric and a filter layer 14 made of short fiber felt impregnated with a synthetic resin, and the water-permeable layer 13 is arranged on the surface side and the filter layer 14 is arranged on the back side in the base layer 11.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a water-permeable artificial turf that imitates natural grass and a method for manufacturing the water-permeable artificial turf. [Background technology]

[0002] Artificial turf is laid in gardens, verandas, parks, grounds, etc. in various facilities such as ordinary homes, tourist facilities, public facilities, accommodation facilities, and sports facilities for purposes such as improving the scenery, suppressing the growth of weeds, reducing the burden on the user during exercise, etc. Some artificial turf used for sports purposes in sports facilities has filler such as rubber chips, sand, crushed stone, etc., between the blade-like piles. Typical artificial turf consists of a base fabric made of woven fabric, resin sheet, resin film, etc., and a pile made of grass-leaf-like synthetic fibers planted into the base fabric. Furthermore, some artificial turf has a backing coating of synthetic rubber, natural rubber, synthetic resin, etc. on the back of the base fabric to improve durability, anti-slip properties, and the strength of the pile threads. Artificial turf is prone to water accumulation on the surface of the base fabric during rainy weather, and to solve this problem, artificial turf that has been made water permeable has been proposed. Patent Document 1 discloses artificial turf that has been made water permeable by providing a plurality of through holes that penetrate the base fabric. Patent Document 2 discloses artificial turf that uses a plain weave fabric as the base fabric and has water permeable holes between the warp threads of the plain weave fabric. Patent Document 2 also discloses an artificial turf that further provides a fiber web on the surface of the plain weave fabric, and the fibers of the fiber web are sandwiched between the gaps in the split and opened filaments and become entangled with the plain weave fabric. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 06-235159 [Patent Document 2] Japanese Patent Application Publication No. 06-235158 Summary of the Invention [Problem to be solved by the invention]

[0004] In permeable artificial turf, the water that permeates from the surface of the base fabric to the backside mixes with wear debris from the infill and pile. The infill and pile wear debris mixed in with the water passes through the through-holes and permeable holes along with the water and flows out through the drainage system, often dissipating into rivers, oceans, etc. Recently, tiny plastics, generally 5mm or less in diameter, such as pile wear debris (i.e., synthetic fiber debris) and rubber chips contained in filler, are known as microplastics and are considered to be environmental pollutants. For this reason, modern artificial turf is being required to be designed to prevent microplastics from leaking out.

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and its objective is to provide a water-permeable artificial turf that can prevent microplastics from leaking to the outside, and a method for manufacturing water-permeable artificial turf. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention is presented below. The water-permeable artificial turf according to claim 1 is a water-permeable artificial turf comprising a base layer and a turf layer made of turf yarns that are raised on the surface side of the base layer, The base layer includes a water-permeable layer made of woven fabric and a filter layer made of short fiber felt coated with synthetic resin, The gist is that the water-permeable layer is disposed on the front side of the base layer, and the filter layer is disposed on the back side. The invention described in claim 2 is the invention described in claim 1, wherein the grass yarn and the backstitch portion of the filter layer protrude above the back surface of the short fiber felt and are covered with the synthetic resin. The invention described in claim 3 is the invention described in claim 1 or 2, wherein the water permeability coefficient of the water-permeable artificial turf is 3.0 × 10 -2 The gist is that it is greater than or equal to cm / s. The invention described in claim 4 is summarized as the invention described in claim 1 or 2, wherein the opening dimension of the short fiber felt is converted into a mesh size of 90 mesh or more and 300 mesh or less. The invention described in claim 5 is the invention described in claim 1 or 2, wherein the basis weight of the short fiber felt is 50 g / m 2 More than 200g / m 2 The gist is as follows. The invention described in claim 6 is the invention described in claim 1 or 2, wherein the short fiber felt is formed by accumulating short fibers, the fiber length of the short fibers is 25 mm or more and 125 mm or less, and the thickness of the short fibers is 1.5 decitex or more and 20 decitex or less. The invention described in claim 7 is the invention described in claim 1 or 2, wherein the amount of the synthetic resin applied to the filter layer is 200 g / m 2 More than 500g / m 2 The gist is as follows. The invention described in claim 8 is the invention described in claim 1 or 2, wherein the basis weight of the woven fabric is 80 g / m 2 More than 200g / m 2 The gist is as follows. The invention described in claim 9 is the invention described in claim 1 or 2, wherein the woven fabric has a weave of either plain weave, twill weave, plain dutch weave, or twill dutch weave, and the thickness of the warp and weft threads is 800 decitex or more and 2000 decitex or less. The invention of claim 10 is a method for manufacturing a water-permeable artificial turf according to claim 1 or 2, The first step is to laminate short fiber felt on the backside of the fabric; After the first step, a second step of tufting turf yarn onto the back surface of the fabric on which the short fiber felt is laminated to form a turf layer; The method further comprises a third step, after the second step, of applying a dispersion of synthetic resin to the short fiber felt to impregnate it. The invention described in claim 11 is the invention described in claim 10, wherein the solid content concentration of the dispersion is 20% by mass or more and 65% by mass or less, The coating amount of the dispersion is 200 g / m2 in dry equivalent. 2 More than 500g / m 2 The gist is as follows. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a water-permeable artificial turf that can prevent microplastics from leaking to the outside, and a method for manufacturing water-permeable artificial turf. [Brief explanation of the drawings]

[0008] The present invention will be further described in the following detailed description, which provides non-limiting examples of exemplary embodiments according to the present invention, and with reference to the mentioned drawings, in which like reference numerals refer to like parts throughout the several views of the drawings. [Figure 1] FIG. 2 is a cross-sectional view showing the water-permeable artificial turf of the embodiment. [Figure 2] FIG. 2 is a plan view showing the base layer of the embodiment as viewed from the front surface side. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will now be described in detail with reference to the accompanying drawings. The matters set forth herein are for illustrative purposes only and are intended to provide an illustrative description of the embodiments of the present invention, with the aim of providing what is believed to be the most effective and easily understandable explanation of the principles and conceptual features of the present invention. In this regard, it is not intended to show structural details of the present invention beyond the extent necessary for a fundamental understanding of the present invention, and the description, taken together with the drawings, will make clear to those skilled in the art how some aspects of the present invention may be actually embodied.

[0010] [1] Permeable artificial grass The water-permeable artificial turf of the present invention is a water-permeable artificial turf 10 comprising a base layer 11 and a turf layer 12 made of turf yarns 21 raised on the surface side of the base layer 11, The base layer 11 includes a water-permeable layer 13 made of woven fabric and a filter layer 14 made of short fiber felt coated with synthetic resin. The base layer 11 is characterized in that the water-permeable layer 13 is disposed on the front side and the filter layer 14 is disposed on the back side (see FIG. 1).

[0011] The water-permeable artificial turf 10 comprises a base layer 11 and a turf layer 12 that is raised on the surface side of the base layer 11. The turf layer 12 is formed by a plurality of turf threads 21 planted in the base layer 11 and standing up on the surface of the base layer 11, so as to resemble blades of grass. In the following description, the surface of the base layer 11 on which the turf threads 21 stand will be referred to as the front side, and the surface opposite to the front side will be referred to as the back side.

[0012] The base layer 11 includes a water-permeable layer 13 made of woven fabric and a filter layer 14 made of a short fiber web coated with a synthetic resin 42 . In the base layer 11 , the water-permeable layer 13 is disposed on the front side of the base layer 11 , and the filter layer 14 is disposed on the back side of the base layer 11 . The base layer 11 has a water-permeable layer 13 arranged on the front side and a filter layer 14 arranged on the back side, which allows water to pass through and also enables the base layer 11 to capture microplastics contained in the water.

[0013] Here, microplastics refer to fine plastics such as abrasion debris from the turf yarn 21, synthetic fiber debris, and rubber chips contained in the filler. Generally, the upper limit of the size of microplastics is 5 mm or less, preferably 2 mm or less, and more preferably 1 mm (1000 μm) or less in terms of average particle size (D50). The lower limit of the size is not particularly limited, but from the viewpoint of a size that can be captured on the base layer 11, the average particle size (D50) can be preferably 10 μm or more, more preferably 40 μm or more, and even more preferably 100 μm or more. The base layer 11, the turf layer 12, and the like that make up the water-permeable artificial turf 10 will be described in detail below.

[0014] (1) Base layer The base layer 11 is a layer on which the turf threads 21 that make up the turf layer 12 are planted, in other words, a layer that holds the planted turf threads 21. As long as the base layer 11 includes the water-permeable layer 13 and the filter layer 14, there are no particular limitations on the other configurations, layer thickness, size such as vertical and horizontal widths in a plan view, shape, etc.

[0015] (1-1) Permeable layer The water permeable layer 13 is provided for the purpose of allowing water such as rainwater to permeate from the front surface to the back surface of the base layer 11 so that the water does not accumulate on the surface of the base layer 11. The material of the water-permeable layer 13 is a woven fabric formed by weaving warp threads 31 and weft threads 32. This fabric has a plurality of meshes 33 formed by the warp threads 31 and weft threads 32 (see FIG. 2). The fabric is permeable, allowing water to pass from one side to the other side through the meshes 33. Furthermore, the fabric is preferably one that allows microplastics to pass from one side to the other side through the meshes 33.

[0016] The material of the warp threads 31 and weft threads 32 is not particularly limited, but synthetic fibers can be mainly used, and regenerated fibers, natural fibers, etc. can also be used in combination with synthetic fibers. The synthetic fibers may be one or more selected from polyolefin fibers such as polyethylene fibers and polypropylene fibers, polyester fibers such as polyethylene terephthalate fibers, polybutylene terephthalate fibers and polytrimethylene terephthalate fibers, polyamide fibers such as nylon 6 fibers and nylon 66 fibers, and polyacrylic fibers. Examples of regenerated fibers include cupra rayon, viscose rayon, and lyocell. Examples of natural fibers include cotton, linen, silk, and wool. Typically, polyethylene fibers or polypropylene fibers can be used for the warp threads 31 and weft threads 32. Polyethylene fibers have the advantages of being durable and resistant to UV rays, as well as suppressing light reflection, thereby creating the texture of natural grass blades. Polypropylene fibers have the advantages of being durable, weather-resistant, water-resistant, and chemical-resistant.

[0017] The thickness of the warp yarns 31 and weft yarns 32 is not particularly limited, but can be 800 decitex or more and 2000 decitex or less. The thickness is more preferably 900 decitex or more and 1500 decitex or less, and even more preferably 1000 decitex or more and 1300 decitex or less. The warp threads 31 and the weft threads 32 may have different thicknesses or may have the same thickness. When the warp threads 31 and the weft threads 32 have different thicknesses, the warp threads 31 and the weft threads 32 may have different thicknesses within the above-mentioned range (800 decitex to 2000 decitex).

[0018] The form of the warp yarns 31 and weft yarns 32 is not particularly limited, but specific examples include ribbon yarns, monofilament yarns, multifilament yarns, flat yarns, split yarns, tape yarns, and the like. The warp yarns 31 and weft yarns 32 may be of different shapes or may have the same thickness. For example, the warp yarns 31 may be ribbon yarns and the weft yarns 32 may be multifilament yarns. Of the above forms, ribbon yarns, flat yarns, split yarns, tape yarns and other strip-shaped yarns are useful because they can easily form large, uniform meshes 33 in the fabric.

[0019] The weave of the woven fabric is not particularly limited, and examples thereof include plain weave, twill weave, satin weave, dutch weave, etc., depending on the weaving method of the warp and weft. Among these, the plain weave, twill weave, plain dutch weave, or twill dutch weave is preferred, from the viewpoints that the mesh 33 can be easily formed uniformly throughout the entire fabric and that good durability can be obtained while maintaining the mesh 33. The size of the mesh 33 of the woven fabric used in the water-permeable layer 13 can be large enough to allow water and microplastics contained in the water to pass through. The size of the mesh 33 can be set by the basis weight and / or weave density of the woven fabric. The weight of the woven fabric is not particularly limited, but is preferably 80 g / m 2 More than 200g / m 2 The basis weight can be set to 100 g / m or less. 2 More than 190g / m 2 More preferably, 120 g / m or less 2 More than 180g / m 2 It can be as follows: The weave density of the woven fabric is not particularly limited, but can be 1 thread / inch or more and 50 threads / inch or less for both the warp and weft. The weave density can be more preferably 5 threads / inch or more and 40 threads / inch or less, and even more preferably 10 threads / inch or more and 30 threads / inch or less.

[0020] (1-2) Filter layer The filter layer 14 is provided for the purpose of allowing water to permeate to the back side of the base layer 11 and capturing microplastics contained in the water inside. The material of the filter layer 14 is short fiber felt impregnated with synthetic resin (see FIG. 1). The short fiber felt is formed in a porous shape by collecting and entangling short fibers 41, and has a plurality of pores 43 formed by the gaps between the fibers. The synthetic resin is impregnated into the short fiber felt by coating or the like, and bonds the short fibers 41 together.

[0021] The material of the staple fibers is not particularly limited, but synthetic fibers can usually be used. The synthetic fibers can be one or more selected from polyester fibers such as polyethylene terephthalate fibers, polybutylene terephthalate fibers, and polytrimethylene terephthalate fibers, polyolefin fibers such as polyethylene fibers and polypropylene fibers, polyamide fibers such as nylon 6 fibers and nylon 66 fibers, and polyacrylic fibers. Of these, polyester fibers such as polyethylene terephthalate fibers can usually be used as the staple fibers. The short fibers may have a fiber length of 25 mm or more and 125 mm or less, more preferably 30 mm or more and 120 mm or less, and even more preferably 40 mm or more and 110 mm or less. The fineness of the staple fibers can be 1.5 decitex or more and 20 decitex or less, more preferably 2 decitex or more and 18 decitex or less, and even more preferably 3 decitex or more and 15 decitex or less.

[0022] The short fiber felt used in the filter layer 14 has water permeability, allowing water to pass from one side to the other side through the pores 43. On the other hand, the short fiber felt used in the filter layer 14 has the ability to capture microplastics inside the filter layer 14 by catching the microplastics on the short fibers when the water being passed through contains microplastics.

[0023] The size of the pores 43 of the short fiber felt used in the filter layer 14 is not particularly limited as long as it is large enough to allow water to pass through (having water permeability) and not allow microplastics to pass through (having collection ability). The water permeability and collection performance of the short fiber felt can be determined by the mesh size of the short fiber felt. The mesh size of the short fiber web can be 90 mesh or more and 300 mesh or less, converted into mesh size. This mesh size can be preferably 100 mesh or more and 250 mesh or less, more preferably 150 mesh or more and 250 mesh or less, converted into mesh size. The size of the pores 43 of the short fiber felt, the opening size, etc. can be set by the basis weight of the short fiber felt. 2 More than 200g / m 2 The basis weight can be set to 70 g / m or less. 2 More than 180g / m 2 More preferably, 80 g / m or less 2 More than 150g / m 2 It can be as follows:

[0024] The synthetic resin impregnated into the short fiber felt is not particularly limited, but may be a resin-based composition such as an elastomer, or a rubber-based composition such as natural rubber or synthetic rubber. Specifically, an SBR-based, acrylic-based, urethane-based, olefin-based composition, or a composition made by mixing two or more of these may be used. The amount of synthetic resin applied (impregnated) to the short fiber felt is not particularly limited, but is preferably 200 g / m 2 More than 500g / m 2 The coating amount (impregnation amount) is more preferably 220 g / m 2 More than 480g / m 2 , and more preferably 250 g / m 2 More than 450g / m 2 It can be said that:

[0025] (2) Grass layer The turf layer 12 is provided for the purpose of imparting the texture of grass blades that natural grass has to the water-permeable artificial turf 10. The turf layer 12 is not particularly limited in size, shape, etc., as long as it is formed by planting a plurality of turf threads 21 into the base layer 11. For example, the turf layer 12 does not necessarily have to be provided on the entire surface of the base layer 11, but may be provided on only a portion of the surface of the base layer 11.

[0026] (2-1) Grass thread The turf threads 21 provide the appearance of grass blades that are found in natural grass. The material of the grass threads 21 is not particularly limited as long as it can achieve the appearance of grass blades, and synthetic fibers can be mainly used, but recycled fibers, natural fibers, etc. can also be used in addition to synthetic fibers. The synthetic fibers may be one or more selected from polyolefin fibers such as polyethylene fibers and polypropylene fibers, polyester fibers such as polyethylene terephthalate fibers, polybutylene terephthalate fibers and polytrimethylene terephthalate fibers, polyamide fibers such as nylon 6 fibers and nylon 66 fibers, and polyacrylic fibers. Examples of regenerated fibers include cupra rayon, viscose rayon, and lyocell. Examples of natural fibers include cotton, linen, silk, and wool. Typically, polyethylene fibers, polypropylene fibers, and polyamide fibers can be used for the turf yarns 21. Polyethylene fibers are highly durable and resistant to UV rays, and have the advantage of being able to mimic the texture of natural grass by reducing light reflection. Polypropylene fibers have the advantage of being durable, weather-resistant, water-resistant, and chemical-resistant, while polyamide fibers have the advantage of being soft to the touch.

[0027] The form of the grass yarn 21 is not particularly limited as long as it can realize the appearance of grass blades, but specific examples include monofilament yarn, multifilament yarn, flat yarn, split yarn, etc. Among these, monofilament yarn and split yarn have the advantage that they can easily realize the appearance of grass blades. Monofilament yarn is a thread made of a single filament (long fiber). Monofilament yarns can be arbitrarily selected or used in various shapes, such as rectangular, elliptical, diamond, and track-shaped cross-sections. There are no particular limitations. Multifilament yarn is a yarn made by twisting together multiple filaments (long fibers). Flat yarn is a flat yarn obtained by cutting a film made of synthetic resin or the like into strips and stretching it. Split yarn is a yarn obtained by splitting a flat yarn into multiple pieces along the direction of extension of the yarn.

[0028] The shape of the grass yarn 21 is not particularly limited as long as it can achieve the appearance of grass blades, but specific examples include a linear straight yarn and a crimped yarn. The form and shape of the turf yarn 21 can be selected from only one type or two or more types from the specific examples given above. In other words, the turf yarn 21 may use only one type of yarn, or two or more types of yarn. For example, the turf yarn 21 can be made of only one type of monofilament straight yarn (see FIG. 1). Alternatively, two types of yarns, a monofilament straight yarn and a monofilament crimped yarn, can be used for the turf yarn 21. In this case, the monofilament straight yarn can create the texture of natural grass blades, and the monofilament crimped yarn can create the texture of thatch (formed by the accumulation of cut and dead grass blades and old roots) that is found in natural grass.

[0029] The thickness of the turf yarn 21 is not particularly limited, but can be 8,000 decitex or more and 20,000 decitex or less, more preferably 10,000 decitex or more and 18,000 decitex or less, and even more preferably 12,000 decitex or more and 17,000 decitex or less. The thickness of the turf yarn 21 is the thickness of the turf yarn 21 when it is in the form of a monofilament yarn, when it is bound into a single bundle, and when it is a split yarn, it is the thickness of a single flat yarn before being split.

[0030] (2-2) Planting method The method of planting the turf yarns 21 into the base layer 11 is not particularly limited, but typically, the turf yarns 21 are bundled together to form a pile 22, and then the pile 22 is sewn into the base layer 11 using a tufting machine or the like (hereinafter also referred to as "tufting") to be planted (see Figure 1). The pile 22 tufted into the base layer 11 can achieve the appearance of grass blades by having the bundled grass yarns 21 branch out and spread apart from each other as they move from the base side (the base layer 11 side) to the tip side.

[0031] When the turf yarn 21 is raised on the surface side of the base layer 11, the pile 22 can be sewn into the base layer 11 by, for example, inserting a tufting needle (sewing needle) into the back side of the base layer 11. A backstitch portion 23 is formed as a seam on the back side of the base layer 11 into which the pile 22 has been sewn. The backstitch portions 23 protrude above the back surface of the staple fiber felt in the filter layer 14. Therefore, the backstitch portions 23 can be covered with a synthetic resin impregnated into the staple fiber felt. In this case, by covering and fixing the backstitch portions 23 with the synthetic resin, it is possible to prevent the turf yarns 21 (pile 22) from falling out of the base layer 11.

[0032] (3) Specifications and functions of water-permeable artificial turf The water permeability of the water-permeable artificial turf 10 can be defined by the water permeability coefficient, which can be measured by a method conforming to JIS A1218 "Soil water permeability test method." Specifically, the permeability coefficient of the water-permeable artificial turf 10 is 3.0 × 10 at the lower limit. -2 The hydraulic conductivity can be more preferably 4.5×10 cm / s or more. -2 cm / s or more, more preferably 6.0 × 10-2 It can be made to be more than cm / s. The upper limit of the hydraulic conductivity is not particularly limited, but is preferably 9.0 × 10 -2 cm / s or less.

[0033] In the water-permeable artificial turf 10, a filler material (not shown) can be filled on the surface of the base layer 11 and between the pile 22 (turf yarns 21) of the turf layer 12. This filler material is filled to keep the water-permeable artificial turf 10 cool and provide cushioning properties. The filler may be granular material such as rubber chips, sand grains, or stone grains. The particle size of the filler is not particularly limited, and any particle size can be selected as desired.

[0034] In the above-described water-permeable artificial turf 10, both the water-permeable layer 13 and the filter layer 14 of the base layer 11 are water-permeable. Therefore, the water-permeable artificial turf 10 allows water such as rainwater to permeate from the front side of the base layer 11 to the back side (outside) and be discharged (see "water" and the arrow extending from it in Figure 1). Meanwhile, rainwater and other water that attempts to permeate the base layer 11 contains wear debris from synthetic fibers such as the turf yarn 21, as well as granular matter such as the filler material described above. Among these granular matter, wear debris from synthetic fibers and those made of synthetic resin such as rubber chips used as filler are called microplastics, and their leakage to the outside is to be avoided.

[0035] The above-mentioned water-permeable artificial turf 10 allows microplastics to pass through the permeable layer 13 of the base layer 11 but cannot pass through the filter layer 14, and can instead be captured inside the filter layer 14 (see "MP" and the arrow extending from it in Figure 1). Therefore, the water-permeable artificial turf 10 can prevent microplastics from being discharged to the outside by capturing the microplastics within the filter layer 14.

[0036] The location where the water-permeable artificial turf 10 can be laid is not particularly limited, and it can be laid in any location, such as a garden, balcony, park, or ground, in a variety of facilities such as ordinary homes, tourist facilities, public facilities, accommodation facilities, and sports facilities. Among these installation locations, sports facilities such as tennis courts, soccer fields, rugby fields, etc. are useful as installation locations for water-permeable artificial turf 10 because they are prone to producing synthetic fiber wear debris and rubber chips are often used as infill material for the purpose of protecting players, etc. Furthermore, in the sports facilities mentioned above, drainage facilities such as catch basins are installed around courts such as tennis courts, soccer courts, and rugby courts. It is particularly useful to lay the water-permeable artificial turf 10 so that it covers such drainage facilities. In other words, the water-permeable artificial turf 10 has excellent water permeability, and when laid over drainage equipment, it can improve the landscape without impairing the drainage capacity of the equipment. Furthermore, the water-permeable artificial turf 10 captures granular matter, including microplastics, in the filter layer 14, thereby preventing microplastics and other contaminants from entering the drainage equipment.

[0037] [2] Manufacturing method for water-permeable artificial turf The manufacturing method of the present invention is a manufacturing method of the above-mentioned water-permeable artificial turf 10, The first step is to laminate short fiber felt on the backside of the fabric; After the first step, a second step of tufting turf yarn onto the back surface of the fabric on which the short fiber felt is laminated to form a turf layer; The method is characterized by comprising a third step, after the second step, of applying a dispersion of synthetic resin to the short fiber felt to impregnate it.

[0038] (1) First step The first step is to laminate a short fiber felt that will become the filter layer 14 on the back surface of the woven fabric that will become the water permeable layer 13 of the base layer 11 of the water permeable artificial turf 10. In this first step, the woven fabric and the short fiber felt are integrated by intertwining their fibers. Specifically, the first step is carried out by placing a woven fabric on a conveyor or the like of the manufacturing equipment and transporting it, accumulating short fibers to be used as short fiber felt on the "back side" of the woven fabric as it is being transported, and intertwining the accumulated short fibers with each other, or intertwining the short fibers with the fibers of the woven fabric, etc. The first step can also be carried out by laminating together a woven fabric and a short fiber felt that have been previously manufactured in separate manufacturing steps. It should be noted that the "back side" of the woven fabric refers to the side of the woven fabric that will be the back side of the permeable layer 13 when it is used as the base layer 11 of the water-permeable artificial turf 10, and does not necessarily refer to the back side of the actual woven fabric in the first step. In other words, the staple fibers to be used for the staple fiber felt may be accumulated on the front side of the actual woven fabric, or on the back side of the actual woven fabric. A specific method for accumulating the staple fibers on the back side of the actual woven fabric is to accumulate the staple fibers on a conveyor or the like to make a staple fiber felt, and then place the woven fabric on the staple fiber felt.

[0039] (2)Second process The second step is a step of forming the turf layer 12. In this second step, for the laminate of the woven fabric and the short fiber felt obtained in the first step described above, turf yarn 21 is tufted onto the woven fabric from the back side where the short fiber felt is laminated. Specifically, tufting is performed by sewing pile 22, which is a bundle of grass yarns 21, into the fabric using a needle. In this second step, when the pile 22 is sewn in, a needle (sewing needle) is inserted from the back side of the fabric, penetrating through both the fabric and the short fiber felt. In the second step, the backstitch portion of the sewn-in pile 22 is formed on the back surface of the staple fiber felt.

[0040] (3) Third step The third step is to impregnate the short fiber felt with synthetic resin. Specifically, the third step is carried out by applying a synthetic resin dispersion liquid prepared in advance to the back surface of the short fiber felt and impregnating the short fiber felt with the synthetic resin. In this third step, when the synthetic resin dispersion is applied, the synthetic resin dispersion is also applied to the backstitch portions of the pile 22 formed on the back surface of the staple fiber felt in the second step. As a result, in the manufactured water-permeable artificial turf 10, the backstitch portions 23 protrude above the back surface of the filter layer 14 and are coated with synthetic resin 42 (see Figure 1).

[0041] In the third step, the method for applying the synthetic resin dispersion is not particularly limited, and specific examples include spray coating, roll coating, and direct coating. The solid content concentration of the dispersion may be 20% by mass or more and 65% by mass or less. The solid content concentration may more preferably be 25% by mass or more and 55% by mass or less, and even more preferably 30% by mass or more and 50% by mass or less. When the solid content concentration is within the above range, the dispersion can be easily spread on the back surface of the short fiber felt and can be easily impregnated into the short fiber felt. The amount of the dispersion to be applied is not particularly limited, but is preferably 200 g / m in dry equivalent. 2 More than 500g / m 2 The coating amount is more preferably 220 g / m 2 More than 480g / m 2 , and more preferably 250 g / m 2 More than 450g / m 2 It can be said that: [Example]

[0042] The present invention will be described in more detail below with reference to examples. However, these examples are merely examples shown for the convenience of explanation, and the present invention is not limited to these examples in any sense.

[0043] [1] Specimen specifications (1) Base layer [Permeable layer] A plain weave of warp yarn (polypropylene, ribbon yarn) and weft yarn (polypropylene, ribbon yarn) (weave density: 24 threads / inch (warp yarn), 18 threads / inch (weft yarn)), with a weight of 150g / m2 Textile. [Filter layer] Short fiber felt obtained using short fiber (PET fiber, 100 decitex) and synthetic resin (SBR latex). The basis weight of the short fiber felt [g / m 2 ] and the amount of synthetic resin applied [g / m 2 (dry equivalent)] should be adjusted appropriately for each sample. (2) Grass layer The pile (polyethylene fiber, monofilament, 9500 decitex / 11 filaments) is tufted from the back side of the base layer, and then cut and adjusted so that the pile height (the height from the surface of the base layer to the tip of the turf threads, i.e. the thickness of the turf layer) is 20 mm.

[0044] [2] Performance evaluation (1) Permeability coefficient Using a "constant water level permeability tester" based on the provisions of JIS A1218 "Soil permeability test method", the water permeability Q (cm) at a water temperature of 20°C was measured by a constant water level permeability test. 3 ) and measure the water permeability Q (cm 3 ) and the hydraulic conductivity k (cm / s) was calculated using the following (Equation 1). k=(L / h)×[Q / (A×T)] (Formula 1) In the above formula (1), L is the thickness of the sample (cm), h is the water level difference (cm), and A is the area of ​​the sample in plan view (cm 2 ), T: measurement time (s), L = 2 cm (thickness of base layer), h = 5.8 cm, A = 460.25 cm 2 , T=60s. (2) Collection performance At a tennis court, each sample was laid on top of the cover (stainless steel mesh plate) of a drainage pit installed around the court. After one month had passed, the inside of the drainage pit was visually inspected to see how much pile debris (wear debris from turf threads) had accumulated, and the condition was evaluated using the following two levels of ○ or ×. ○: Almost no clumps of pile waste of the same color (green) as the grass yarn were found. ×: A large lump of pile waste of the same color (green) as the grass thread was found.

[0045] [3] Examples and Comparative Examples Example 1 Using the sample shown in [1] above, the base layer was placed with the permeable layer on the front side and the filter layer on the back side, and the weight of the short fiber felt was 80 g / m 2 , synthetic resin coating amount 300g / m 2 The sample was the same as that of Example 1 (on a dry basis). The results of the performance evaluation of Example 1 are shown in Table 1.

[0046] (Comparative Example 1) In the sample shown in [1] above, the base layer uses only the fabric of the permeable layer, and the back side of this fabric is coated with synthetic resin (SBR latex) at a rate of 640 g / m 2 After applying the coating and backing processing, holes with a diameter of 3mm to 4mm are formed at a density of 397 pieces / m 2 The specimen was subjected to a hole drilling process (water permeation process) using a heating pin so that the specimen was formed as shown in the figure, and used as a specimen for Comparative Example 1. The results of the performance evaluation of Comparative Example 1 are shown in Table 1. (Comparative Example 2) The sample was the same as that of Example 1, except that the water-permeable layer was placed on the back side and the filter layer on the front side, and a hole-punching process (water-permeable processing) using a heated pin was performed on the base layer through the filter layer in the same manner as in Comparative Example 1, to create the sample of Comparative Example 2. The results of the performance evaluation of Comparative Example 2 are shown in Table 1.

[0047] [Table 1]

[0048] (Consideration 1) From the results in Table 1, Example 1 had a high water permeability coefficient, excellent water permeability performance, and excellent collection performance. The coefficient of permeability of Comparative Example 1 was lower than that of Example 1, and the collection performance was also evaluated as ×, indicating that the performance was clearly inferior. Although the same woven fabric was used in Comparative Example 1 and Example 1, the coefficient of permeability of Comparative Example 1 was clearly lower. The reason for this is thought to be that the mesh of the woven fabric was blocked by the backing processing. Comparative Example 2 had a lower permeability coefficient than Example 1 and was also rated as x in collection performance, clearly showing inferior performance. When observing collection performance in Comparative Example 2, traces of water (wastewater) overflowing from the surface of the sample onto the side edge of the catch basin were observed, which suggests that the collection performance of the filter layer was barely functioning.

[0049] Examples 2 to 5 Using the sample shown in [1] above, the weight of the short fiber felt was set to Example 2: 80 g / m 2 , Example 3: 100 g / m 2 , Example 4: 150 g / m 2 , Example 5: 200 g / m 2 The synthetic resin coating amount is 200 g / m 2 As a result, samples of Examples 2 to 5 were prepared. The results of the performance evaluation of Examples 2 to 5 are shown in Table 2.

[0050] [Table 2]

[0051] (Consideration 2) The results in Table 2 show that Examples 2 to 5 are excellent in water permeability and collection performance. Furthermore, when comparing Examples 2 to 5, the permeability coefficient decreased as the basis weight of the short fiber felt increased, and this result showed that the permeability coefficient can be adjusted to the desired value by changing the basis weight of the short fiber felt.

[0052] Examples 6 to 9 Using the sample shown in [1] above, the weight of the short fiber felt was 80 g / m 2 The amount of synthetic resin applied was 250 g / m in Example 6. 2 , Example 7: 300 g / m 2 , Example 8: 400 g / m 2 , Example 9: 500 g / m 2 As a result, samples of Examples 6 to 9 were prepared. The results of the performance evaluation of Examples 6 to 9 are shown in Table 2.

[0053] [Table 3]

[0054] (Consideration 3) The results in Table 3 show that Examples 6 to 9 are excellent in water permeability and collection performance. Comparing Examples 6 to 9 with Example 2, it was shown that the permeability coefficient generally decreased as the amount of synthetic resin applied increased. This result showed that the permeability coefficient can be adjusted to a certain extent by adjusting the amount of synthetic resin applied. [Industrial Applicability]

[0055] The water-permeable artificial turf of the present invention can be suitably used in a variety of facilities, particularly sports facilities. [Explanation of symbols]

[0056] 10;Permeable artificial grass, 11; base layer, 12; grass layer, 21; grass yarn, 22; pile, 23; backstitch part, 13; permeable layer, 31; warp thread, 32; weft thread, 33; mesh, 14; filter layer, 41; short fiber, 42; synthetic resin, 43; pores.

Claims

1. A water-permeable artificial turf comprising a base layer and a grass layer made of grass yarn raised on the surface side of the base layer, The base layer includes a water-permeable layer made of woven fabric and a filter layer made of short fiber felt impregnated with synthetic resin, In the base layer, the water-permeable layer is disposed on the front surface side and the filter layer is disposed on the back surface side, The grass yarn has a backstitch portion that protrudes above the back surface of the staple fiber felt in the filter layer and is covered with the synthetic resin, The water permeability coefficient of the water-permeable artificial turf is 4.43 x 10 －２ cm / s or more 8.84×10 －２ cm / s or less, the amount of the synthetic resin applied to the filter layer is 200 g / m 2 or more and 500 g / m 2 or less; The weight of the short fiber felt is 80 g / m 2 or more and 200 g / m 2 or less, The filter layer made of short fiber felt has water permeability that allows water to pass through and collection ability that allows microplastics with an average particle size (D50) of 10 μm or more and 5 mm or less to be collected inside the filter layer, thereby preventing the outflow of microplastics to the outside. This water-permeable artificial turf is characterized by the fact that the filter layer made of short fiber felt has water permeability that allows water to pass through and collection ability that allows microplastics with an average particle size (D50) of 10 μm or more and 5 mm or less to be collected inside the filter layer.

2. The opening size of the short fiber felt is, in terms of mesh size, 90 mesh or more and 300 mesh or less, The water-permeable artificial turf described in claim 1, wherein the short fiber felt is formed by accumulating short fibers, the fiber length of the short fibers being 25 mm or more and 125 mm or less, and the thickness of the short fibers being 1.5 decitex or more and 20 decitex or less.

3. The weight of the short fiber felt is 80 g / m ２ More than 200g / m ２ is as follows:

2. The water-permeable artificial turf according to claim 1, wherein the water-permeable artificial turf is laid in a sports facility.

4. The mesh size of the short fiber felt is, in terms of mesh size, 90 mesh or more and 300 mesh or less, The short fiber felt is formed by accumulating short fibers, and the fiber length of the short fibers is 25 mm or more and 125 mm or less, and the thickness of the short fibers is 1.5 decitex or more and 20 decitex or less, 2. The water-permeable artificial turf according to claim 1, wherein the water-permeable artificial turf is laid in a sports facility.

5. The weight of the fabric is 80 g / m ２ More than 200g / m ２ is as follows: The water-permeable artificial turf according to claim 1, wherein the woven fabric has a weave of either a plain weave, a twill weave, a plain tatami weave, or a twill tatami weave, and the thickness of the warp and weft threads is 800 decitex or more and 2000 decitex or less.

6. The weight of the fabric is 80 g / m 2 or more and 200 g / m 2 or less, The woven fabric has a weave of any one of plain weave, twill weave, plain dutch weave, and twill dutch weave, and the thickness of the warp and weft yarns is 800 decitex or more and 2000 decitex or less, 2. The water-permeable artificial turf according to claim 1, wherein the water-permeable artificial turf is laid in a sports facility.

7. The method for manufacturing a water-permeable artificial turf according to claim 1, A first step of laminating short fiber felt on the back surface of a woven fabric; After the first step, a second step of tufting turf yarn onto the back side of the fabric on which the short fiber felt is laminated to form a turf layer; and a third step of applying a dispersion of a synthetic resin to the short fiber felt and impregnating the felt with the dispersion after the second step, The solid content concentration of the dispersion is 20% by mass or more and 65% by mass or less, the coating amount of the dispersion is 200 g / m 2 or more and 500 g / m 2 or less in terms of dry weight, The water-permeable artificial turf comprises a base layer and a turf layer made of turf yarn that is raised on the surface side of the base layer, the base layer includes a water-permeable layer made of the woven fabric and a filter layer made of the short fiber felt impregnated with the synthetic resin, In the base layer, the water-permeable layer is disposed on the front surface side and the filter layer is disposed on the back surface side, The grass yarn has a backstitch portion that protrudes above the back surface of the staple fiber felt in the filter layer and is covered with the synthetic resin, The water permeability coefficient of the water-permeable artificial turf is 4.43×10 −2 cm / s or more and 8.84×10 −2 cm / s or less, the amount of the synthetic resin applied to the filter layer is 200 g / m 2 or more and 500 g / m 2 or less; The weight of the short fiber felt is 80 g / m 2 or more and 200 g / m 2 or less, A method for manufacturing water-permeable artificial turf that prevents microplastics from leaking to the outside, characterized in that the filter layer made of short fiber felt has water permeability that allows water to pass through and collection ability that captures microplastics with an average particle size (D50) of 10 μm or more and 5 mm or less.

8. The solid content concentration of the dispersion is 20% by mass or more and 65% by mass or less, The coating amount of the dispersion was 200 g / m in dry equivalent. ２ More than 500g / m ２ is as follows: The method for manufacturing a water-permeable artificial turf according to claim 7, wherein the water-permeable artificial turf is laid in a sports facility.

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