JP2019060098A - Artificial lawn - Google Patents

Abstract

To provide an artificial lawn capable of maintaining a good appearance for an extended period.SOLUTION: An artificial lawn is provided. The artificial lawn comprises a base material having a front face and a rear face, and a large number of piles imitating lawn leaves standing on the front face of the base material. The large number of piles include straight piles and crimped piles. The straight piles and the crimped piles are composed of polyethylene. Taking the total fineness of the straight pile as S1 and the total fineness of the crimped pile as S2: 1.0≤S1/S2≤1.5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to artificial turf and a method of manufacturing the same.

  In recent years, artificial turf has spread in various athletic competition facilities such as soccer fields, rugby fields, and baseball fields. In many cases, such artificial turf is manufactured by planting a large number of piles imitating turf leaves on a substrate. And, as the artificial turf spreads widely, various functions such as texture, durability, and workability that are similar to natural turf are required for the artificial turf, and as a device to realize further functions, There has been proposed an artificial turf in which a straight pile (hereinafter, straight pile) and a crimped pile (hereinafter, crimped pile) are combined (see Patent Documents 1 and 2). In Patent Document 1, the straight pile is made of polyethylene, and the crimped pile is made of nylon 66. Further, in Patent Document 2, the straight pile is made of polypropylene, and the crimped pile is made of nylon 6.

JP 2014-47596 A JP, 2010-248802, A

  As described above, in Patent Documents 1 and 2, the straight pile and the crimped pile are different materials. Therefore, a difference occurs in the advancing speed of light resistance deterioration, water immersion deterioration, etc. of these piles, and only one of the piles is deteriorated by the secular change, and the appearance of the artificial turf becomes different from the initial use. In addition, when the crimped pile is made of a nylon-based material and the straight pile is made of polyethylene, the nylon-based material is inferior to polyethylene in water resistance, so the grass leaf of the crimped pile is It can be a situation where only one thing gets stuck and one that breaks out may occur.

  An object of the present invention is to provide an artificial turf capable of maintaining the appearance for a long time and a method for producing the same.

  The artificial turf according to the first aspect of the present invention comprises a base material having a front surface and a rear surface, and a large number of piles imitating turf leaves standing on the front surface of the base material. The plurality of piles include straight piles and crimped piles. The straight pile and the crimped pile are made of polyethylene. When the total fineness of the straight pile is S1 and the total fineness of the crimped pile is S2, 1.0 ≦ S1 / S2 ≦ 1.5.

  The artificial turf according to the second aspect of the present invention is the artificial turf according to the first aspect, wherein the straight pile and the crimped pile are made of the same polyethylene material.

  The artificial turf according to the third aspect of the present invention is the artificial turf according to the first aspect or the second aspect, wherein the straight pile and the crimped pile are implanted at the same implantation site on the base material ing.

  The artificial turf according to the fourth aspect of the present invention is an artificial turf according to any one of the first to third aspects, and 1.2 ≦ S1 / S2.

The method for producing artificial turf according to the fifth aspect of the present invention includes the following steps.
(1) producing a straight yarn composed of polyethylene.
(2) producing crimped yarn composed of polyethylene.
(3) The base comprising a straight pile and a crimped pile simulating a sod leaf respectively formed from the straight yarn and the crimped yarn by implanting the straight yarn and the crimped yarn on a substrate 1 is a step of manufacturing an intermediate of the artificial turf having a large number of piles standing on the surface of a wood, where the total fineness of the straight pile is S1 and the total fineness of the crimped pile is S2; Manufacturing the intermediate such that 0 ≦ S1 / S2 ≦ 1.5.
(4) A backing agent is applied to the back surface of the base material contained in the intermediate to prevent the pile from falling off the base material, and the high temperature environment in which the backing agent is lower than the melting point of the crimped yarn Drying at the bottom.

  The method of producing an artificial turf according to a sixth aspect of the present invention is the method of producing an artificial turf according to the fifth aspect, wherein the crimped pile has a smaller cross-sectional area than the straight pile.

  The method of producing an artificial turf according to a seventh aspect of the present invention is the method of producing an artificial turf according to the fifth aspect or the sixth aspect, wherein the crimped pile has a lower turf length than the straight pile.

  The method for producing an artificial turf according to an eighth aspect of the present invention is the method for producing an artificial turf according to any one of the fifth to seventh aspects, wherein the step of drying the backing agent of (4) is The step of drying the backing agent in a high temperature environment of 100 ° C. or higher.

  According to the present invention, the turf leaves of artificial turf are formed by at least two types of piles, a straight pile and a crimped pile. Therefore, natural texture similar to natural grass can be realized. Also, both straight pile and crimped pile are made of polyethylene. Therefore, not only the straight pile and the crimped pile have a relatively long life, but the rate of deterioration of both is relatively the same. Moreover, durability is further improved by being 1.0 <= S1 / S2 <= 1.5. As a result, the appearance of artificial turf is maintained for a long time.

The side view of the artificial turf concerning one embodiment of the present invention.

  Hereinafter, an artificial turf according to an embodiment of the present invention and a method of manufacturing the same will be described with reference to the drawings.

<1. Artificial turf>
The artificial turf 1 according to the present embodiment is installed on an installation surface such as an asphalt surface or the ground in various sports facilities such as a soccer field, a rugby field, and a baseball field. As shown in FIG. 1, the artificial turf 1 has a base material 2 and a large number of piles 3 imitating turf leaves standing on the surface 2 a of the base material 2. The substrate 2 is formed in a sheet shape, and the pile 3 is implanted on the substrate 2 at a predetermined interval. In addition, on the back surface 2 b of the base 2, a backing layer 4 for preventing the pile 3 from falling off from the base 2 is formed.

  The piles 3 on the substrate 2 contain different kinds of piles. In the present embodiment, two types of piles are planted on the base material 2, one is a straight pile (straight pile) 31, and the other is a crimped pile (crimped pile) 32. The straight pile 31 does not have to extend completely in a straight line, and may be curved to some extent (can include bending), but the degree of bending referred to here means a degree of bending slightly due to its own weight or the like. means. On the other hand, the crimped pile 32 has a shape which may be curved (including bending) in various directions even in a state where no external force is applied.

  In the artificial turf 1, by combining the straight pile 31 and the crimped pile 32, a natural texture similar to natural turf is realized. In addition, the crimped pile 32 can act like a spring to support the straight pile 31 and prevent the straight pile 31 from falling. Therefore, also in this sense, the combination of the crimped pile 32 and the straight pile 31 improves the appearance of the artificial turf 1.

  Although the material and form of the substrate 2 are not particularly limited, for example, the substrate 2 can be formed as a plain woven fabric made of a resin material. Of course, it can also be formed as a twill cloth. As a resin material, typically, thermoplastic resins such as polypropylene and polyethylene can be selected.

  The material of the backing layer 4 is also not particularly limited. For example, the backing layer 4 can be composed of SBR latex, an acrylic resin, a urethane resin, a composite of these, or the like. The backing layer 4 can be omitted.

  The straight pile 31 is made of polyethylene. Further, in the present embodiment, the straight pile 31 is formed using monofilament yarns (yarns), but of course, it can also be formed using multifilament yarns (yarns). The straight pile 31 of the present embodiment is fixed to the base material 2 by sewing the yarn to be the straight pile 31 into the base material 2 using a tufting machine. The length L1 (average value) from the surface 2a of the base material 2 to the tip of the straight pile 31 is not particularly limited, but can be relatively shortened to 20 mm ≦ L1 <50 mm (generally called a short pile), It can also be relatively long, such as 50 mm ≦ L1 ≦ 70 mm (generally called long pile). However, it is preferable that 15 mm ≦ L1 ≦ 40 mm. In addition, although the straight pile 31 inclines more or less by self weight etc. on the base material 2, L1 here is the length when the straight pile 31 is extended linearly. In addition, although the straight pile 31 of the present embodiment is flat, the cross-sectional shape of the straight pile 31 is various such as an elliptical shape, a hollow shape, a continuous filament, an irregular shape (for example, triangle, square, star). It can be shaped. In addition, the cross section of the pile 3 means the cross section in the surface orthogonal to the extension direction of a turf.

  On the other hand, the crimped pile 32 is also made of polyethylene, like the straight pile 31. In the present embodiment, in particular, the straight pile 31 and the crimped pile 32 are made of the same polyethylene material. Here, "the same polyethylene material" means that the density, the melting point, the composition, and the combination of the anticorrosion stabilizer, the pigment and the like are the same or substantially the same. In the present embodiment, the crimped pile 32 is also formed using a monofilament yarn (yarn), but of course, it can also be formed using a multifilament yarn (yarn). In addition, the crimped pile 32 of the present embodiment is also fixed to the base 2 by sewing the yarn to be the crimped pile 32 into the base 2 using a tufting machine. The length L2 (average value) from the surface 2a of the base 2 to the tip of the crimped pile 32 is not particularly limited, but preferably 15 mm ≦ L2 ≦ 40 mm, and in the present embodiment, the length of the straight pile 31 is Is the same as L1. In addition, although the crimped pile 32 is crimped, L2 here is the length when extending the crimped pile 32 in linear form. Further, "identical" as used herein does not mean that L1 and L2 are completely identical, and an error within ± 5% is allowed. Moreover, although the crimped pile 32 of the present embodiment is flat, the cross-sectional shape of the crimped pile 32 is also elliptical, hollow, continuous thread, irregular shape (for example, triangle, square, star), etc. It can be of various shapes.

  The straight pile 31 and the crimped pile 32 do not necessarily have to be made of only polyethylene, and may contain materials other than polyethylene. In the present embodiment, when a specific part such as the straight pile 31, the crimped pile 32, the base 2, the backing layer 4 and the like is "made of (specific material)", most of the part is made of the material It means to be constituted, quantitatively, it shall be said that weight percent W of the material at the site is 50% or more. From the viewpoint of increasing the strength of the pile 3, the weight percentage W of polyethylene of the pile 3 is preferably 60% or more, more preferably 70% or more, and still more preferably 80% or more. % Or more is more preferable, and 95% or more is more preferable.

  Here, the grass height (average value) of the straight pile 31 is H1, and the grass height (average value) of the crimped pile 32 is H2. At this time, in the present embodiment, H1> H2. In addition, H1 is the height (average value) from the surface 2a of the base material 2 to the uppermost point of the straight pile 31 in a state where no external force (except its own weight) is applied to the artificial turf 1, and H2 and Is the height (average value) from the surface 2 a of the base material 2 to the uppermost point of the crimped pile 32 in the same state. In the embodiment in which L1 and L2 are the same, H2 / H1 ≦ 3/4 is preferable, and H2 / H1 ≦ 2/3 is more preferable. As the value of H2 / H1 decreases, the crimp of the crimped pile 32 increases, and the grass length of the crimped pile 32 decreases relative to the straight pile 31, and the crimped pile 32 firmly secures the lower portion of the straight pile 31. It is because it becomes possible to support it. On the other hand, when the value of H2 / H1 becomes too small, the crimped pile 32 can support only the root of the straight pile 31, so H2 / H1、1⁄4 is preferable, H2 / H1 ≧ It is more preferable to be 1/3, and it is further preferable to satisfy H2 / H1 ≧ 1/2. When the above numerical range is satisfied, the lodging of the straight pile 31 is more effectively suppressed.

  When the area (average value) of the cross section of the straight pile 31 is A1 and the area (average value) of the cross section of the crimped pile 32 is A2, in this embodiment, A1> A2. It is more preferable that A1 / A2> 1.5, still more preferably A1 / A2> 2, still more preferably A1 / A2> 2.5, and A1 / A2> 3.0. It is further preferred that That is, as the value of A1 / A2 increases, the crimped pile 32 becomes thinner with respect to the straight pile 31, and the process of crimping can be facilitated.

  In this embodiment, at each of the planting points P1 on the base material 2, both the straight pile 31 and the crimped pile 32 are planted. In the example of FIG. 1, six straight piles 31 and sixteen crimped piles 32 are planted at the same planting point P1. That is, the pile 3 of one planting point P1 is composed of six straight piles 31 and sixteen crimped piles 32. However, the total number of piles 3 at the same planting point P1 and the numbers of straight piles 31 and crimped piles 32 at the same planting point P1 can be changed as appropriate.

  When the total fineness of the straight pile 31 is S1 and the total fineness of the crimped pile is S2, 1.0 ≦ S1 / S2 ≦ 1.5. The total fineness of the pile 3 is a value obtained by multiplying the fineness per one pile 3 by the number per one strain of the pile 3 (half amount of the pile 3 standing from the planting point P1 of 1). Moreover, the fineness per one pile 3 means the weight per unit length of the pile 3. That is, by satisfying 1.0 ≦ S1 / S2, the amount of the straight pile 31 with respect to the crimped pile 32 is secured. As a result, the straight pile 31 is relatively thick or the number thereof is increased, and the appearance of the artificial grass 1 is improved. In addition, the straight pile 31 is less likely to fall due to repeated treading by the athlete or the like, and the durability of the artificial grass 1 is also improved. On the other hand, by satisfying S1 / S2 ≦ 1.5, the amount of crimped pile 32 with respect to the straight pile 31 is secured, and the straight pile 31 is less likely to fall due to repeated treading pressure of the athlete etc Both appearance and durability are improved.

  Further, S1 <6000 dtex is preferable per one strain (each half of piles 31 and 32 standing from the planting point P1 of 1), more preferably 500 dtex ≦ S1 ≦ 5900 dtex, and 4000 dtex ≦ It is more preferable that S1 ≦ 5,900 dtex. In addition, it is preferable that 300 dtex ≦ S2 ≦ 8000 dtex per strain, more preferably 300 ≦ S2 ≦ 6000 dtex, and more preferably 2000 dtex ≦ S2 ≦ 5500 dtex.

  The width of the cross section of the straight pile 31 is W1, the thickness of the cross section of the straight pile 31 is D1, the width of the cross section of the crimped pile 32 is W2, and the thickness of the cross section of the crimped pile 32 is D2. . The width W1 is the maximum width of the cross section, and the thickness D1 is the maximum value of the thickness measured along the direction orthogonal to the direction of the width W1. The same applies to W2 and D2. At this time, 0.3 mm ≦ W1 ≦ 20 mm is preferable, and 0.8 mm ≦ W1 ≦ 20 mm is more preferable. It is preferable that 0.1 mm ≦ D1 ≦ 0.5 mm. Further, it is preferable that 0.1 mm ≦ W2 ≦ 10 mm. Further, it is preferable that 0.05 mm ≦ D2 ≦ 0.5 mm.

  As described above, in the present embodiment, both the straight pile 31 and the crimped pile 32 are made of polyethylene. Therefore, not only the straight pile 31 and the crimped pile 32 have a relatively long life, but also the progress rates of deterioration of both are relatively the same. Moreover, durability is further improved by being 1.0 <= S1 / S2 <= 1.5. As a result, the appearance of the artificial turf 1 is maintained for a long time. Further, since the straight pile 31 and the crimped pile 32 are both made of polyethylene, they can be collectively melted, reshaped, and suitable for recycling after the useful life has passed. Also, when recycling, it can be reused in a wide range of applications.

<2. Manufacturing method>
Next, an example of a method of manufacturing the artificial turf 1 will be described. First, a polyethylene material mixed with a green colorant is prepared as a material for forming the straight pile 31 and the crimped pile 32 (hereinafter referred to as a pile material). The polyethylene material may be, for example, a density of 0.926 g / cm ³ linear low-density polyethylene.

  Next, the above pile material is put into an extruder and melt extrusion is performed under a predetermined temperature condition. Thus, a thread-like resin material is extruded from the opening of the extruder. The temperature condition at this time can be, for example, 180 ° C., which is higher than the melting point of the pile material. Subsequently, the thread-like pile material extruded from the extruder is cooled and solidified in a water tank, and this thread is uniaxially drawn. After that, the yarn is manufactured by performing relaxation heat treatment in a hot water tank. At this time, for example, the temperature of the water tank that performs cooling and solidification can be set to 30 ° C. Moreover, as an aspect of uniaxial stretching, uniaxial stretching can be performed in a 90 ° C. to 100 ° C. water bath by roll stretching. The temperature of the thermal water tank that performs the relaxation heat treatment can be 90 ° C. to 100 ° C. After the relaxation heat treatment, the yarn is wound up to form a yarn roll.

  In the present embodiment, different types of yarns are formed according to the above manufacturing method. More specifically, in order to form two types of piles 3 (straight piles 31 and crimped piles 32), two types of yarns are manufactured. Hereinafter, the yarn for the straight pile 31 is referred to as a straight yarn, and the yarn for the crimped pile 32 is referred to as a crimped yarn. In the present embodiment, the straight yarn and the crimped yarn are the same in material but different in cross sectional shape (area, width and thickness) and denier per yarn. In addition, crimped yarn is crimped and processed into crimped yarn after relaxation heat treatment and before being wound up as a yarn roll. As a method of crimp treatment of yarns for artificial turf piles, various methods such as heat treatment, etc. are known, so detailed description will be omitted here.

  Subsequently, after producing yarn rolls of straight yarns and crimped yarns, yarns fed from these yarn rolls are continuously implanted on the substrate 2 using a tufting machine. In this embodiment, three yarn rolls of straight yarn and eight yarn rolls of crimped yarn are prepared, and a total of 11 yarns fed out from each are twisted into one bundle, and then this twisted yarn is produced. Are sewn to the base material 2 by a tufting machine. The number of yarn rolls of straight yarns and crimped yarns used in the step of tufting is the total fineness S1 of straight piles 31 and crimped piles 32 contained in the artificial turf 1 finally manufactured. The total fineness S2 is appropriately determined so as to satisfy the above-described numerical range. Further, in the step of tufting, a bundle of looped yarns standing from the base material 2 is formed, and the top of the bundle is cut. As a result, from each planting point P1 on the base material 6, six turf leaves consisting of straight piles formed from straight yarns and sixteen turf leaves consisting of crimped piles formed from crimped yarns A total of 22 turf leaves will stand up. Further, the grass length L1 of the straight pile and the grass length L2 of the crimped pile are the same. Hereinafter, the member which consists of the base material 2 and piles 31 and 32 which were formed by this is called an intermediate.

  Subsequently, in order to fix the pile 3, a backing agent is applied to the back surface 2 b of the base material 2 contained in the intermediate to form a backing layer 4. Thereafter, the applied intermediate of the backing agent is dried in a high temperature environment to obtain a final artificial turf 1. The temperature condition T1 in this drying step is a temperature lower than the melting point T2 of the crimped pile 32 (in the present embodiment, the same as the melting point of the straight pile 31), for example, T2 = 110 ° C. to 130 ° C. (ambient temperature). Is preferred. From the viewpoint of shortening the drying step, it is preferable to set T2 ≧ 100 ° C. or higher.

<3. Modified example>
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible unless it deviates from the meaning. For example, the following modifications are possible. Moreover, the gist of the following modifications can be combined as appropriate.

<3-1>
The planting point P1 where the straight pile 31 is planted and the planting point P1 where the crimped pile 32 is planted may be different. In this case, for example, the planting point P1 at which the straight pile 31 is planted and the planting point P1 at which the crimped pile 32 is planted are alternately arranged, and the whole straight grass 31 It is preferable that the crimped pile 32 and the crimped pile 32 be mixed as evenly as possible. Moreover, when the planting point P1 in which the straight pile 31 and the crimped pile 32 are planted differs, depending on the case, a level | step difference will be formed in the part of the straight pile 31 and the part of the crimped pile 32. FIG. Therefore, in this sense, as in the above embodiment, in order to maintain a more natural feeling, it is preferable to configure the straight pile 31 and the crimped pile 32 to rise from the same planting point P1.

<3-2>
A filler can also be filled between the piles 3 on the surface 2 a of the substrate 2. In addition to serving as a cushioning material to prevent the player from getting injured during play, this filling can also protect the turf. In addition, it is possible to adjust the degree of elasticity of the ball used in the game, to control the runnability of the player, and also to improve the play performance of the game on the artificial grass 1 . As the filler, at least one of an elastic filler and a hard filler can be used. As the elastic filler, for example, a rubber chip made of a crushed product of a waste tire can be used. As a hard filler, sand can be used, for example.

Examples of the present invention will be described below, but the present invention is not limited to the following examples.
Example 1
The artificial turf (Example 1) which is the artificial turf which has the composition concerning the above-mentioned embodiment by the above-mentioned manufacturing method, and fulfills the following conditions was produced. That is, the straight yarn was a polyethylene monofilament yarn having a width W1 = 0.85 mm and D1 = 0.24 mm. The crimped yarn was a polyethylene monofilament yarn having a width W2 = 0.65 mm and a thickness D2 = 0.12 mm, and was crimped by heat treatment. Then, these two types of yarns are bundled to form a yarn bundle, and the interplanting interval (the number of gauges) in the lateral direction is 5/16 inches, and the interplanting interval (the number of stitches) in the longitudinal direction is 6 / inch. The yarn bundle was tufted on a polypropylene substrate. At this time, per yarn bundle (per one strain), the total fineness S1 = 5550 dtex (1850 dtex / line × 3) and the total fineness S2 = 4000 dtex (500 dtex / line × 8), and L1 = L2 = 30 mm. In addition, a mixture of SBR latex and urethane resin was applied to the back surface of the substrate to form a backing layer.

(Example 2)
The artificial turf according to Example 2 was produced in the same manner as in Example 1 except that the total fineness S2 (per one strain) of crimped yarn was set to 5000 dtex (500 dtex / tube × 10).

(Comparative example 1)
The artificial turf according to Comparative Example 1 was produced in the same manner as Example 1 except that the total fineness S2 (per one strain) of the crimped yarn was set to 6000 dtex (500 dtex / 12 ×).

(Comparative example 2)
The artificial turf according to Comparative Example 2 was prepared in the same manner as Example 1 except that the total fineness S2 (per one strain) of crimped yarn was set to 3500 dtex (500 dtex / 7 pieces).

(Comparative example 3)
The artificial turf according to Comparative Example 3 has a total fineness S2 (per one strain) = 5600 dtex (700 dtex / x 8) of crimped yarn, a width W2 = 0.7 mm, and a thickness D2 = 0.13 mm. Were produced in the same manner as in Example 1.

(Comparative example 4)
The artificial turf according to Comparative Example 4 has a total fineness of crimped yarn S2 (per one strain) = 3500 dtex (700 dtex / x 5), a width W2 = 0.7 mm, and a thickness D2 = 0.13 mm. Were produced in the same manner as in Example 1.

(test)
The artificial turf according to Examples 1 and 2 and Comparative Examples 1 to 4 is manufactured, and thereafter, each artificial turf is repeatedly subjected to compression treatment, and the appearance of the artificial turf after repeated compression treatment (hereinafter, artificial turf after compression) Was visually evaluated. The repeated compression process was performed using the testing machine described in JP-A-2013-148413. More specifically, a flat indenter with a diameter of 100 mm is placed on an artificial turf, compressed to a load of 70 kg, and released after reaching 1000 cycles of 20 seconds / time repeatedly to perform compression repeatedly. The process was carried out. In addition, the vertical rebound height of the ball and the slipperiness of the sole were evaluated for the artificial turf after compression. The vertical repulsive height of the ball is an average of five times when the artificial grass was placed on the asphalt installation surface and the soccer ball was vertically dropped from a height of 2 m. Slipperiness of the soles was evaluated according to the method defined by the Japan Football Association.

The above test results are as shown in the table below.

  In Comparative Examples 2 and 4, after repeated compression processing, the straight yarn was bent in the V-shape, and it was difficult to restore the appearance (Evaluation "B"). Moreover, in Comparative Examples 1 and 3, after repeated compression processing, the low-layer portion of the crimped yarn was hot and the grass height was reduced (Evaluation "B"). On the other hand, in Examples 1 and 2, the crimped yarn was not broken even after repeated compression treatment, and after 1 day the grass height was restored to about 80%, and when it was further brushed, the appearance was in the initial state It did not change with (evaluation "A").

1 artificial turf 2 substrate 2a front surface 2b back surface 3 pile 31 straight pile 32 crimped pile 4 backing layer

Claims (8)

An artificial turf comprising a substrate having a front surface and a rear surface, and a large number of piles imitating turf leaves standing on the front surface of the substrate,
The multiple piles include straight piles and crimped piles,
The straight pile and the crimped pile are made of polyethylene,
Assuming that the total fineness of the straight pile is S1, and the total fineness of the crimped pile is S2,
1.0 ≦ S1 / S2 ≦ 1.5,
Artificial turf. The straight pile and the crimped pile are composed of the same polyethylene material,
The artificial turf according to claim 1. The straight pile and the crimped pile are implanted at the same planting point on the base material,
The artificial turf according to claim 1 or 2. 1.2 ≦ S1 / S2,
The artificial turf according to any one of claims 1 to 3. A method of producing artificial turf,
Producing a straight yarn composed of polyethylene,
Producing crimped yarn composed of polyethylene;
The surface of the substrate, including straight piles and crimped piles imitating turf leaves respectively formed from the straight yarns and the crimped yarns by implanting the straight yarns and the crimped yarns on the substrate. A step of manufacturing an intermediate of the artificial turf having a large number of piles standing up, wherein the total fineness of the straight pile is S1, and the total fineness of the crimped pile is S2, 1.0 ≦ 5. Manufacturing the intermediate so that S1 / S2 ≦ 1.5;
A backing agent is applied to the back surface of the base material contained in the intermediate to prevent the pile from falling off from the base material, and the backing agent is dried in a high temperature environment lower than the melting point of the crimped yarn. Step of
including,
How to make artificial turf. The crimped pile has a smaller cross-sectional area than the straight pile,
The method according to claim 5. The crimped pile has a lower grass height than the straight pile,
The manufacturing method of Claim 5 or 6. The step of drying the backing agent is a step of drying the backing agent under a high temperature environment of 100 ° C. or higher.
The manufacturing method according to any one of claims 5 to 7.