JPH1150412A - Artificial turf - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the function, by forcing piles to pierce an elastic base material sheet having a specified thickness in the thickness direction and tufting them to form U-shapes. SOLUTION: Synthetic resin piles 11 having a specified length in the thickness direction are forced to pierce an elastic base material sheet 12 having a specified thickness and the central part is exposed to the bottom face 15 of the base material sheet 12 and both ends thereof are exposed on the upper face of the base material sheet 12 and tufted to make a nearly U-shaped form, to constitute the artificial turf 10. Then, the turf 10 is laid down on a flat substrate 13 and joint-sealing sand 14 or the like is stuffed between respective piles 11. Then, the bottom face 15 of the base material sheet 12 is formed to have a rugged face to give a preferable elasticity thereto. And a resin film 18 is stuck on at least one of the bottom face 15 and the upper face 16 of the base material sheet to prevent damage of the base material sheet 12 resulting from spikes of players and increase the strength against the drawing forces of piles and further, prevent damage of the base material sheet caused by the drawing forces of piles. In this way, an appropriate elasticity can be obtained and the strength against the drawing forces of piles can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an artificial turf, and more particularly, to a tufted artificial turf in which a pile is planted on an elastic base material having a predetermined thickness.

[0002]

2. Description of the Related Art Artificial turf is composed of a large number of synthetic resin piles planted on a planar base cloth with a predetermined weight per unit area. This is advantageous in terms of workability and maintenance compared to natural turf. It is widely used in various athletic stadiums such as tennis courts and soccer ball fields.

In recent years, so-called sand-containing artificial turf, in which particles such as sand are contained in the grass between the piles, has become mainstream in order to obtain a feeling closer to that of natural lawn. When elasticity is required, an elastic layer having a predetermined thickness is provided on the back surface of the base fabric.

However, in this case, in addition to the material cost of the elastic layer itself, it is necessary to adhere the elastic layer to the base cloth, so that the overall cost cannot be denied. In addition, since the base fabric restrains the deformation of the elastic layer, there is a problem that the desired elastic effect cannot be obtained.

Therefore, for example, a water-permeable mat in which a fibrous material is implanted on one side of a water-permeable elastic layered body in which elastic masses are bonded (see JP-A-8-113907: Conventional Example 1), inorganic particles, and foams A ground structure in which a filler such as an elastomer is bound with non-foamed urethane and an artificial turf is embedded in the surface (see Japanese Patent Application Laid-Open No. Hei 4-369551:
Conventional example 2) or an artificial turf in which a large number of yarns are scattered and implanted in a state of being bundled on a synthetic resin mat substrate, and each yarn protrudes from the surface of the mat substrate by a predetermined length (see Japanese Utility Model Application Publication No. −116
See Japanese Patent Publication No. 506: Conventional example 3) has been proposed.

[0006] According to these prior arts, an elastic base material can provide a feeling of grounding with high elasticity.
By directly laying the pile on the base material, the necessity of the base fabric woven of synthetic fibers can be eliminated, and the manufacturing cost can be reduced accordingly.

[0007]

However, in the prior art 1, since the fibrous material (pile) is implanted only on one side of the elastic layered material, the drawback strength of the fibrous material is relatively low. There is. In the conventional example 2, the artificial turf is manufactured by arranging artificial turf on a mold at regular intervals and manufacturing the artificial turf by filling a material in the mold and hardening the mold. Is limited by the formwork. Further, in Conventional Example 3, the yarn (pile) is implanted through the mat substrate, but the base end is not fixed to the bottom surface of the mat substrate. There is a problem that the pull-out strength is low, and the pull-out strength is easy.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. It is an object of the present invention to provide a low-cost, highly elastic grounding feeling and extremely high pile pull-out strength. To provide artificial grass.

[0009]

Means for Solving the Problems In order to achieve the above object, an invention according to claim 1 is directed to an artificial turf in which a plurality of piles are planted on a base material, the base material having a predetermined thickness having elasticity. It is characterized in that the pile is made of an elastic base material, and the pile is penetrated through the sheet-like elastic base material in the thickness direction thereof and is tufted in a substantially U-shape.

In this case, examples of the sheet-like elastic substrate include urethane, vinyl chloride, polyethylene, NR rubber (natural rubber), SBR rubber (styrene-butadiene rubber), CR (chloroprene rubber), and EPDM (ethylene propylene rubber). A material having water permeability is preferable. In the case of non-water permeability, water permeability such as drilling may be applied.

Further, either a foam or a non-foam may be used, but a foam is preferred in view of the ease of penetration of the sewing needle when tufting the pile. When it is a foam, it may be either open cells or closed cells. The thickness of the sheet-like elastic base material is 3 to 15 mm in consideration of securing elasticity and tufting property of the pile.
It is preferable to set to.

The pile to be tufted on the sheet-like elastic base material includes, for example, various kinds of polychlorinated synthetic resins such as polyethylene and polyvinyl chloride, nylon, PET (polyethylene terephthalate), PBT (polybutylene terephthalate) and polypropylene. Various synthetic resins and, in some cases, natural materials can be used. As the form of the pile, a straight or looped monofilament type, multifilament type, filament type, etc. can be selected, and the presence or absence of crimping, slitting, twisting, coloring, and the like, and the degree thereof are also arbitrary. .

After tufting the pile, if necessary, a backing material such as latex rubber may be applied to the bottom surface of the sheet-like elastic base material to fix the pile base. In addition, when latex rubber is employed as the backing material, and when the water permeability of the sheet-like elastic base material is hindered by the backing material, the water permeability of the base material can be reduced by appropriately forming a water-permeable hole with a heated needle or the like. You only need to secure it.

This artificial turf is made of, for example, concrete, asphalt, asphalt concrete,
It is used by laying it on a flat base such as a compacted crushed stone or an appropriate elastic layer. According to the present invention, the pile penetrates the sheet-like elastic base material in the thickness direction and has a substantially U-shaped tuft. Therefore, the pull-out resistance can be improved as compared with the related art.

According to a second aspect of the present invention, an unevenness is formed on the bottom surface of the sheet-like elastic base material. According to this, the elasticity is further imparted to the sheet-like elastic base material by the unevenness, and particularly in the case of an artificial turf containing a filler having a filler between piles, the filler is effectively solidified by the elasticity. , And a good feeling of contact with the ground can be maintained for a long time.

Typical examples of the uneven shape include a dimple shape and a wavy shape. In any case, the number of the uneven portions is preferably 2 to 100 peaks per 100 mm. That is, when the number of peaks is less than two per 100 mm, a so-called uneven feeling that the unevenness is felt below the feet occurs.
On the other hand, if more than 100 peaks per 100 mm,
Since it approaches a flat surface, a buffer effect due to the unevenness cannot be obtained, which is not preferable.

According to a third aspect of the present invention, at least one of the bottom surface and the top surface of the sheet-shaped elastic substrate is covered with a resin film. In this case, if the coating with the resin film is on the upper surface of the base material, it is possible to prevent the sheet-like elastic base material from being damaged by the spike of the player. In addition, if the coating with the resin film is the bottom surface of the base material, the pull-out strength of the pile can be improved, and the breakage of the base material due to the pull-out of the pile can be prevented.

The resin film used here includes:
For example, urethane, vinyl chloride, polyvinyl chloride, polyethylene, NR rubber (natural rubber), SBR rubber (styrene-butadiene rubber), CR (chloroprene rubber),
EPDM (ethylene propylene rubber) or the like can be employed. This resin film is adhered to one or both of the bottom surface and the top surface of the sheet-shaped elastic base material,
It can be attached by an appropriate means such as thermal welding, ultrasonic welding, vapor deposition, etc., but when the same material as the sheet-like elastic base material is used, thermal welding is preferably employed.

According to a fourth aspect of the present invention, a filler is filled between the piles. For example, sand or an elastic filler having an appropriate average particle size may be used alone or mixed at a predetermined ratio. Is filled into the grass. In the artificial turf containing the filler, solidification of the filler is effectively suppressed by the elasticity of the sheet-like elastic base material, and it is possible to maintain the stab and sliding of the spike for a game piercing the filler satisfactorily for a long time. Become.

Here, as fillers, NR rubber (natural rubber), SBR rubber (styrene-butadiene rubber), C
R (chloroprene rubber), EPDM (ethylene propylene rubber), pulverized products of various rubbers such as urethane can be adopted, and the shape thereof is arbitrary such as spherical, fibrous, polygonal, and organic.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention will be described with reference to the drawings for better understanding of the technical concept of the present invention.

As shown in FIG. 1 (A), this artificial turf 10 is formed by penetrating a synthetic resin pile 11 in a thickness direction through a sheet-like elastic base material 12 having a predetermined thickness having elasticity. Each of the piles 11 is made of tufts having a substantially U-shape and is laid on a ground 13 as a flat stable base.
The space between them is filled with, for example, mesh sand 14 to a predetermined height.

In this embodiment, the pile 11 is made of twisted yarn of nylon and polypropylene. The pile 11 has a predetermined length, and penetrates in the thickness direction of the sheet-like elastic base material 12 so that the central portion thereof is the same as the base material 1.
The base 2 is tufted in a substantially U-shape so as to be exposed on the bottom surface 15 and both ends thereof are exposed on the upper surface 16 of the base material 12.

A large number of piles 11 are regularly or irregularly planted on the sheet-like elastic base material 12 and are not shown in the drawing. The bottom surface 15 is bonded and fixed with a backing material such as latex rubber.

According to this embodiment, the sheet-like elastic substrate 1
Reference numeral 2 denotes a 20-fold foam made of polyethylene, the upper surface 16 of which is formed flat, while the bottom surface 15 is formed with irregularities. If the thickness of the sheet-like elastic substrate 12 is less than 3 mm, it is difficult to obtain desired elasticity. If the thickness exceeds 15 mm, the length of the pile 11 needs to be set large. Taking into account the fact that there is a tendency that the tufting process cannot be performed smoothly,
It is preferable that the thickness is set within a range of 3 to 15 mm.

As the irregularities formed on the bottom surface 15 of the sheet-like elastic substrate 12, as shown in FIG. 1A, wavy undulations may be continuously formed at regular intervals, or as shown in FIG.
As shown in (B), a concave spherical surface (dimple) 17 having a predetermined depth may be used.

When latex rubber is used as the backing material for fixing the pile 11, there is a possibility that the water permeability of the base material 12 may be impaired by the backing material.
Therefore, when it is desired to maintain the water permeability of the sheet-like elastic base material 12, the water-permeable holes may be appropriately formed by a heated needle or the like.

When forming irregularities on the bottom surface 15 of the sheet-like elastic base material 12, if the irregularities are less than two peaks per 100 mm, athletes or pedestrians passing through the turf surface give a so-called uneven feeling. 1 per 100mm
If the number of peaks exceeds 00, the bottom surface 15 is flattened, so that a desired elastic effect cannot be obtained. Therefore, the number of irregularities formed on the bottom surface 15 is preferably in the range of 2 to 100 peaks per 100 mm.

In this embodiment, a resin film 18 made of polyethylene is applied to the bottom surface 15 and the top surface 16 of the sheet-like elastic base material 12, respectively. in this way,
Since the sheet-like elastic base material 12 and the resin film 18 are made of the same polyethylene, the resin film 18 is bonded to the base material 12 by heat welding.

According to the artificial lawn 10, the base material 12
Since it is a sheet-like elastic body having a predetermined thickness and having elasticity, desired elasticity can be obtained without providing a separate elastic layer. Further, since the pile 11 penetrates the sheet-like elastic base material 12 in the thickness direction and is tufted in a substantially U-shape, the pull-out strength of the pile 11 is improved as compared with the prior art artificial grass described as a conventional example. . The pile 11 can be further enhanced in pull-out strength by bonding and fixing the pile 11 on the bottom surface 15 of the sheet-like elastic base material 12 with a backing material.

Further, according to the artificial turf 10, since the unevenness is formed on the bottom surface 15 of the sheet-like elastic base material 12, the base material 12 is provided with even better elasticity. In this case, in particular, the number of irregularities is 2 to 100 mm.
By setting 100 mountains, it will not give athletes or pedestrians who pass through the grass the feeling of incongruity,
A desired effect can be obtained without flattening the bottom surface.

Further, the bottom surface 15 of the sheet-like elastic substrate 12
Alternatively, by attaching the resin film 18 to the upper surface 16, it is possible to prevent the base material 12 from being damaged by spikes of the competitor, and to improve the pull-out strength of the pile 11,
In addition, it is possible to prevent the substrate 12 from being damaged due to the removal of the pile 11. By using the same material as the sheet-like elastic base material 12 for the resin film 18,
Can be stuck to it by a relatively simple means of heat welding.

When the artificial turf 10 is an artificial turf containing a filler in which meshes 14 and the like are filled between the piles 11, the solidification of the meshes 14 (filler) is caused by the elasticity of the sheet-like elastic base material 12. Is effectively suppressed by the
4 can maintain the initial good state of the spikes and slippage of the competition spike.

[0034]

EXAMPLE Next, the material and bottom shape of the sheet-like elastic base material,
Actually constructing multiple types of artificial turf by changing the presence or absence of resin film and filler and the method of planting piles, measure and evaluate impact force, filler solidification, durability, pile pullout strength, Since the overall evaluation was performed in consideration of the results of the above, description will be made with reference to Table 1 along with Comparative Examples.

[0035]

[Table 1]

The impact force was evaluated according to DIN 18035.
And the smaller the value, the better. Here, the value of the impact force is 350 kg
f or less, it is suitable for an athletic field where a fierce competition such as soccer is performed.
If it exceeds gf, the turf surface will be felt hard, which may hinder some sports.

The solidification of the filler is evaluated by filling the sand with a predetermined height between the piles and measuring the spring constant of the turf surface using a test device (2050 manufactured by Intesco Corporation). It was assumed to be. Specifically, the diameter 50
mm test piece (cylindrical end face) is placed on the grass surface at a loading speed of 50 mm /
min, repeatedly press-contact 10,000 times with a load loop of 0 to 100 kgf, and then assume a load when an adult male walks on the turf surface, a load speed of 30 mm / min, 80 kgf.
The spring constant when the test pieces were pressed against each other was measured.

Further, the durability was evaluated by a scratch tester 20 shown in FIG. This scratch tester 20
The artificial lawn 10 is placed and fixed on a rotatable disk 21, and a roller 23 having a spike pin 22 protruding from the peripheral surface is brought into contact with the artificial lawn 10, and the disk 21 is rotated 60 times per minute to obtain a roller. By rolling the No. 23 for one hour, the scratching of the turf surface by the spikes for competition was simulated.

The durability was evaluated on a 5-point scale out of 5 by observing the situation thereafter. Further, the evaluation of the pull-out strength of the pile was performed by holding the pile on a pull-out chuck and performing a pull-out test at 10 cm / min. The higher the value, the better. The final comprehensive evaluation was based on the above measured values or evaluations, and was evaluated on a five-point scale of ×, Δ, ○, ○ to ◎, ◎, where ◎ was the highest.

Example 1 A sheet-shaped elastic body made of polyethylene and having a thickness of 5 mm was used as a base material. An artificial grass was formed by penetrating a pile made of polypropylene in the thickness direction of the base material and tufting it in a substantially U-shape. The base of the substrate was flat, and no resin film and no filler were used. As a result, the impact force was 430 kgf, the durability was evaluated as 3, the pull-out strength of the pile was 8 kgf, and the overall evaluation was ○.

Example 2 A base material made of polyethylene having a thickness of 5 mm and dimples on the bottom surface of 2 mm per 100 mm
A sheet-like elastic body formed on zero ridges was used. By passing a polypropylene pile through the thickness direction of the substrate,
It was tufted in the shape of a letter to make an artificial lawn. Note that no resin film and no filler were used. As a result, the impact force is 41
0 kgf, the durability evaluation was 3, the pull-out strength of the pile was 8 kgf, and the overall evaluation was 〜 to ◎.

Example 3 A 5 mm thick sheet-like elastic body made of polyethylene was used as a base material. Then, after a resin film made of polyethylene is integrally applied to the upper surface of the base material by a heat welding method, a pile made of polypropylene is penetrated in the thickness direction of the base material and tufted in a substantially U shape. Artificial grass. Note that the bottom surface of the substrate was flat, and no filler was used. As a result, the impact force is 430 kgf,
The evaluation of durability was 4, the pull-out strength of the pile was 8 kgf, and the overall evaluation was ○ to ◎.

Example 4 A sheet-like elastic body made of polyethylene and having a thickness of 5 mm was used as a base material. Then, after a resin film made of polyethylene is integrally applied to the bottom surface of the base material by a heat welding method, a pile made of polypropylene is pierced in the thickness direction of the base material and tufted in a substantially U shape. Artificial grass. Note that the bottom surface of the substrate was flat, and no filler was used. As a result, the impact force is 430 kgf,
The durability is rated as 3, and the pull-out strength of the pile is 10 kgf.
And the overall evaluation was 〜 to ◎.

Example 5 A sheet-like elastic body made of polyethylene and having a thickness of 5 mm was used as a base material. Then, after a resin film made of polyethylene is integrally applied to the upper and lower surfaces of the base material by a heat welding method, a pile made of polypropylene is penetrated in the thickness direction of the base material so as to be substantially U-shaped. Tufted into artificial grass. Note that the bottom surface of the substrate was flat, and no filler was used. As a result, the impact strength was 430 kgf, the durability evaluation was 4, the pull-out strength of the pile was 10 kgf, and the overall evaluation was ○ to ◎.

Example 6 The base material was made of polyethylene and had a thickness of 5 mm, and dimples were formed on the bottom surface at a rate of 2 mm per 100 mm.
A sheet-like elastic body formed on zero ridges was used. Then, after a resin film made of polyethylene is integrally applied to the upper and lower surfaces of the base material by a heat welding method, a pile made of polypropylene is penetrated in the thickness direction of the base material so as to be substantially U-shaped. After tufting, sand was filled in the grass between the piles to form an artificial lawn. As a result, the impact force is 295kg
f, the solidification of the filler was 47 kgf / mm, the evaluation of the durability was 5, the pull-out strength of the pile was 10 kgf, and ◎ was obtained as an overall evaluation.

<Comparative Example 1> As a base material, a plain weave base material made of polypropylene was used, and a pile made of polypropylene was penetrated through the base material to tuft in a substantially U-shape to obtain an artificial grass. The impact strength was 630 kgf, the durability was 1, the pull-out strength of the pile was 7 kgf, and the overall evaluation was x.

<Comparative Example 2> A sheet-like elastic body made of polyethylene and having a thickness of 5 mm and a flat bottom surface was used as a base material. A pile made of polypropylene was implanted into the substrate from its upper surface to form an artificial lawn. As a result, the impact force was 431
kgf, durability evaluation is 2, pile pullout strength is 4
kgf, and the overall evaluation was Δ.

<Comparative Example 3> A base cloth made of polyethylene plain weave was used as a base material, and a polypropylene pile was pierced through the base cloth to form a substantially U-shaped tuft. Was filled with sand to make an artificial lawn. Impact force is 580kgf, solidification of filler is 300kgf / m
m, durability evaluation 3, pile pull-out strength 7kg
f, and the overall evaluation was Δ.

From the above evaluations, Examples 1 to 6 were used.
In Comparative Example 2, since the sheet-like elastic body is employed as the base material, the impact force and the solidification of the filler are significantly improved as compared with Comparative Example 1. In Comparative Example 2, since the pile was simply implanted, the pull-out strength of the pile was poor.

In Examples 1 to 6, since the pile is penetrated through the base material and tufted in a substantially U-shape,
The pull-out strength of the pile is significantly improved as compared with Comparative Example 2. Although the comparative example 1 is also a penetrating tuft, since the base material is a plain-woven base fabric, the pull-out strength of the pile is slightly lower than that of the examples 1 to 6.

Further, in the second embodiment, dimple processing is performed as irregularities on the bottom surface of the base material, so that better elasticity can be obtained than in the first embodiment.

Further, in Example 3, since the upper surface of the base material was covered with the resin film, the evaluation of the durability was improved as compared with Example 2. In Example 4, since the bottom surface of the base material was covered with the resin film, the pull-out strength of the pile was improved as compared with Example 2.

In the fifth embodiment, both the bottom surface and the top surface of the base material are covered with the resin film, so that both the durability and the pull-out strength of the pile are improved as compared with the second embodiment. In Example 6, since the filler was filled between the piles, the impact force, the solidification of the filler, the durability, and the pull-out strength of the pile were improved in higher dimensions as compared with other Examples and Comparative Examples. As a result, a high overall evaluation has been obtained.

The present invention is not limited to the above embodiments, but includes materials, shapes, dimensions, forms, numbers, and locations of bases, piles, irregularities on the bottom of bases, resin films, fillers, and the like. Can be arbitrarily changed as long as the present invention can be achieved.

[0055]

As described above, according to the present invention,
A sheet-like elastic body of a predetermined thickness is used as the base material, and the pile is penetrated in the thickness direction with respect to the base material and is tufted in a substantially U shape, so that it has moderate elasticity as a whole, and An artificial grass with high pile pull-out strength can be obtained.

Further, by forming irregularities on the bottom surface of the sheet-like elastic base material, it is possible to provide the base material with better elasticity. Further, by integrally applying the resin film to the bottom surface or the top surface of the base material, it is possible to prevent the base material from being damaged by spikes of the competitor and to improve the pile pull-out strength.

In the artificial turf containing the filler, the solidification of the filler is effectively suppressed by the elasticity of the base material, so that the spikes and the slippage of the game spike piercing the filler are improved over a long period of time. Can be maintained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a schematic perspective view schematically showing a scratch tester.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Artificial turf 11 Pile 12 Sheet-like elastic base material 14 Filler sand 15 Bottom surface 16 Upper surface 17 Concave and concave concave surface (dimple) 18 Resin film

Claims (4)

[Claims] 1. An artificial turf comprising a plurality of piles planted on a base material, wherein the base material is formed of a sheet-like elastic base material having a predetermined thickness having elasticity, and the pile is formed with respect to the sheet-like elastic base material. An artificial turf characterized by being substantially U-shaped tufted through the thickness of the turf. 2. The artificial turf according to claim 1, wherein irregularities are formed on a bottom surface of the sheet-like elastic base material. 3. The artificial turf according to claim 1, wherein at least one of the bottom surface and the top surface of the sheet-like elastic substrate is covered with a resin film. 4. The artificial lawn according to claim 1, wherein a filler is filled between the piles.