JP2002115206A - Artificial lawn and artificial-lawn stadium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a line from bending due to the elongation of an artificial lawn. SOLUTION: In the artificial lawn, in which piles 2 are implanted to a base fabric 1 and which is positioned and placed on a substrate by filling a granular material among the piles, elongation in the case of load in 196 N/50 mm width (20 kgf/50 mm width) reaches 25% or less at a measured value by a tension test stipulated in JIS L-1096 (sections among chucks of 300 mm and a rate of pulling of 100 mm/min) in elongation in the 45 deg. direction to the pile implanting direction of the base fabric 1.

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 an artificial turf stadium laid on a ground, and more specifically, suppresses the growth of the artificial turf due to an external force and prevents a decrease in strength at a joint portion. It relates to the technology to be performed.

[0002]

2. Description of the Related Art Artificial turf containing sand has been employed in tennis courts and in recent years, in the surface of sports using spike shoes such as soccer and baseball. The artificial turf containing sand is, as schematically shown in FIG.
An artificial turf 3 manufactured by planting a pile 2 is laid on a foundation 5 at a construction site, and the grass between the piles 2 is filled with a granular material 6 such as sand or a rubber chip.

In a factory, the artificial turf 3 is, for example, 3.6 m
Since the artificial turf 3 is adjacent to the artificial turf 3 in the width direction and the length direction at the construction site, the artificial turf 3 is appropriately joined to each other via the joint tape 7 to which the adhesive 7a is applied. You. The artificial turf with sand has the advantage that the movement is suppressed by the weight of the granular material 6 to be filled, so that it is easy to construct and easy to peel off, so that it does not take much time for repair. I have.

[0004]

However, since the artificial turf 3 is merely laid on the base 5 and is not bonded to the base 5, the shift occurs when an excessive external force is repeatedly applied. In particular, in a soccer field or a baseball field, the base 5 may be an elastic layer such as a rubber chip pavement in order to ensure playability, but if the base 5 has elasticity, the movement of the artificial turf 3 is further increased. growing.

In the case of other uses, the artificial turf containing sand is usually laid on ascone pavement, but may be laid on crushed stone or the like by rolling compaction. In general,
Since the crushed stone layer has elasticity as compared with the ascon pavement, the artificial turf 3 can be easily moved even in such a case.

As described above, since the artificial turf 3, 3 is integrally joined via the joint tape 7 having the adhesive 7a, the joint portion is more joined to the other portion (non-joint portion). The movement is also restricted. Since the non-joint part is merely laid, the restraining force against the movement is small.

[0007] To facilitate understanding of the problem to be solved,
FIG. 9 shows the vicinity of a goal post G of a soccer field in which a plurality of artificial grasses 3 are spread and filled with sand. The chain line in the figure is the joint J of the artificial turf 3 with the joint tape 7,
The space between the joints J is a non-joint H which is simply laid.

[0008] In a soccer game, a large number of players move toward the goal post G in practice as well as in an actual game. Non-joint part H due to external force at this time
If the elongation of the joint portion J is f1 and the elongation of the joint portion J is f2, the joint portion J has a large restraining force, so that f1> f2. As a result, the non-joint portion H undergoes oblique extension shown by an arrow F, This causes the line I to bend as shown in FIG.

[0009]

According to the present invention, in an artificial turf containing sand, elongation of the artificial turf due to the application of an external force can be effectively suppressed, and line bending can be prevented. Therefore, the present invention has several features described below.

That is, the present invention relates to an artificial turf laid on a ground by laying a pile on a base cloth and filling a granular material between the piles. The elongation in the 45 ° direction with respect to the planting direction is the tensile test specified by JIS L-1096 (300 mm between chucks, 100 mm / min tensile speed).
196N / 50mm width (20kgf /
It is characterized in that the elongation under a load of (50 mm width) is 25% or less, preferably 20% or less.

According to a preferred aspect of the present invention, the base cloth is composed of two upper and lower base cloth laminates, and the base cloth laminate is provided with a backing material for an implanted pile. In this case, in the tensile test (200 mm between chucks, tensile speed 100 mm / min) in the tensile test specified in JIS L-1096, the maximum strength of the above-mentioned base fabric laminate on the longitudinal and transverse strength / elongation curves was 588 N. / 50 mm width (60 kgf / 50 mm width) or more, and the difference between the elongation at the maximum strength and the elongation at break is preferably less than 10%, which is also one of the features of the present invention. .

In the present invention, JIS L-10
When performing the tensile test specified in 96, when measuring the elongation of the base cloth in the 45 ° direction and when measuring the elongation of the johnite part in a specific example described later, the distance between the chucks was set to 300 mm, When measuring the elongation of the base fabric in the vertical and horizontal directions, the distance between the chucks is set to 200 mm.

According to another feature of the present invention, the upper base fabric of the base fabric laminate is JIS L-109.
The maximum strength in the vertical and horizontal directions in the tensile test (200 mm between chucks, 100 mm / min of pulling speed) specified in No. 6 is 490 N / 50 mm width (50 kgf / 5
0 mm width) or more and the elongation is 18% or less, and 30 to 70 g of a synthetic resin flocculent per square meter is adhered to the lower base fabric in the base fabric laminate. Tensile test specified in JIS L-1096 for the lower fabric (200 mm between chucks, 100 mm / mi tensile speed)
n) the maximum strength in the longitudinal and transverse directions is 196 N /
It is 50 mm width (20 kgf / 50 mm width) or more.

In the artificial turf of the present invention, the pile may be planted on the base cloth by tufting, and the gauge is preferably 10 mm or more. According to this, even when the granular material to be filled in the grass contains an elastic granular material having a relatively large particle size, such as a rubber chip, for example, it can be easily filled. Therefore, the present invention includes an embodiment in which the elastic particles are included in the particles to be filled.

The present invention also includes an artificial turf stadium on which the artificial turf is laid. That is, the present invention is applicable to various artificial turf sports facilities such as tennis courts, soccer stadiums, baseball stadiums, and athletic stadiums.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a description will be given of a 45 ° direction with respect to a pile laying direction of a base cloth. (For the configuration of the artificial turf, see FIG. 8 described above.) FIG. 1 shows the stitch direction (vertical direction in FIG. 1) and the gauge direction (FIG. 1) when tufting the pile 2 on the base cloth 1. At the side of the pile) of the base fabric 1
The 5 ° direction is a 45 ° direction with respect to both the stitch direction and the gauge direction.

Therefore, the sample D to be subjected to the tensile test (300 mm between chucks and a pulling speed of 100 mm / min) specified in JIS L-1096 is a base cloth 1
As shown in FIG. 1, a material cut from the pile 2 (after the planting of the pile 2) and having a width of, for example, 50 mm in a 45 ° direction in both the stitch direction and the gauge direction is used. The length may be longer than the distance between the chucks.

In the present invention, the pile 2 may be a general one used for artificial turf containing sand. That is, the material is a synthetic resin such as polypropylene, polyethylene, or nylon, and may be any of split yarn and monofilament yarn. Also, the thickness is 500
It may be about 0 to 11,000 dtex.

In order to suppress the elongation of the artificial turf in the oblique direction (45 ° direction) due to external force, a first base fabric for maintaining the dimensional stability in the vertical and horizontal directions and a second base fabric for maintaining the dimensional stability in the oblique direction. It is effective to form a base fabric laminate in which a fabric is overlapped. As the combination, the following first embodiment and second embodiment are exemplified.

[First Embodiment] First base cloth; woven cloth such as polypropylene, polyethylene, polyethylene terephthalate, etc. Single yarn; flat yarn, monofilament, spuntex, etc. Single yarn decitex; 500 to 1100 decitex. Number of shots: 10 to 30 shots / inch both vertically and horizontally. Weight; about 50 to 200 g / m ² . Second base fabric; a nonwoven fabric made of short fibers such as polypropylene, polyethylene, and polyethylene terephthalate. Single yarn; monofilament, spuntex, etc. Single yarn decitex; 5 to 50 decitex. Fiber length; 50-150 mm. Weight; about 50 to 200 g / m ² .

[Second Embodiment] First base cloth: a woven cloth of polypropylene, polyethylene, polyethylene terephthalate or the like as in the first embodiment. Single yarn; flat yarn, monofilament, spuntex, etc. Single yarn decitex; 500 to 1100 decitex. Number of shots: 10 to 30 shots / inch both vertically and horizontally. Weight; about 50 to 200 g / m ² . Second base cloth: Woven cloth of the same performance level as the first base cloth (not necessarily the same), made of cotton or polypropylene terephthalate uniformly adhered thereto. Single yarn; flat yarn, monofilament, spuntex, etc. Single yarn decitex; 5 to 50 decitex. Fiber length; 50-150 mm. Adhesion amount: 30 to 70 g / m ² . Attachment method: punching, fusion, etc.

Preferably, the first base cloth is used as an upper base cloth and the second base cloth is used as a lower base cloth. The second base fabric of the second embodiment is laminated such that the attached cotton-like material faces the first base fabric.

In both the first and second embodiments, the first
The base fabric is a general fabric used in conventional artificial turf containing sand, and is required for securing the dimensional stability of the artificial turf in the vertical and horizontal directions. The dimensional stability in the oblique direction is determined by the second base fabric. Since the second base fabric is provided with nonwoven fabric or short fiber cotton, expansion and contraction in the vertical, horizontal and oblique directions is uniform.

By impregnating the backing laminate with the backing material, elongation can be more effectively suppressed. The backing material may be used as a backing material during the production of artificial turf. For example, SBR latex, urethane,
Examples thereof include resins such as acryl, which are cured by heating or at room temperature by crosslinking the material itself or evaporating moisture in the material.

The backing material is impregnated after the pile is laid. Note that, depending on the urethane resin, there is a case where elongation of the artificial turf can be suppressed even when only one base cloth is used because of high crosslinkability.

Further, a woven cloth of polypropylene, polyethylene, polyethylene terephthalate, or the like, which is substantially the same in performance as the first base cloth, is placed on the second base cloth in the driving direction.
The same dimensional stability can be obtained by overlapping bias-like base cloths cut in the direction of ゜.

Further, a woven cloth of polypropylene, polyethylene, polyethylene terephthalate, or the like having a performance similar to that of the first base cloth is prepared, and then heated to fuse the warp yarns and the weft yarns. However, the dimensional stability in the vertical, horizontal and oblique directions can be improved.

It is to be noted that the mere overlapping of the two base cloths does not cause the difference between the elongation at the maximum strength and the elongation at break in the strength-elongation curve in the tensile test to be less than 10%. Even in the case of a combination of cloths, a desired elongation suppression effect and dimensional stability can be obtained by operating bonding conditions such as integrating the two base cloths by, for example, fusing, bonding, or needle punching. You can do so.

If the artificial turf containing sand is constructed with the artificial turf using the respective base cloths, the dimensional stability in the oblique direction (see the arrow F in FIG. 9) is improved, and the artificial turf is stretched by an external force. Is suppressed, and there is no possibility that line bending occurs.

When two base cloths are used as described above in order to secure the dimensional stability in the oblique direction, there is a point to be noted. Referring to FIG. 2, non-joint portion H that is simply laid down can flexibly cope with external force because artificial turf 3 is stretched even when external force pulls artificial turf 3. 7 adhesive 7
The portion fixed by a restricts elongation.

Therefore, in the vicinity of the joint J, a portion which is extended by an external force, that is, a range JN which receives the stress becomes narrow. This means that the stress is concentrated in the range JN, and as a result, the joint J may be broken at the point j adjacent to the bonding portion.

Therefore, the balance between the upper base cloth (first base cloth) and the lower base cloth (second base cloth) is important in terms of strength. That is,
If there is a large difference in strength and elongation at break between the upper and lower base fabrics,
The stress concentrates on one of the base fabrics. As a result, the non-joint portion H has a sufficient strength, for example, a maximum strength of 490 N / in a tensile test (300 mm between chucks and a pulling speed of 100 mm / min) specified in JIS L-1096. 5
Even if the width is 0 mm (50 kgf / 50 mm width), sufficient strength is not guaranteed at the point j adjacent to the bonding portion of the joint J.

According to an experiment, in order to obtain a sufficient strength at the bonded portion (the above j point) of an artificial turf in which two base cloths are piled up and a pile is tufted and backed, the following conditions must be satisfied. I just found out.

That is, in an artificial turf in which two base cloths are piled up, a pile is tufted and backing is performed, a tensile test (200 mm between chucks, a pulling speed of 100 mm / s) of the base cloth laminated body specified in JIS L-1096 is carried out. min)
Is 588 N / 50 mm width (60 kgf / 50 mm) on the strength and elongation curves in the vertical and horizontal directions.
Width) or more, and the difference between the elongation at the maximum strength and the elongation at break may be less than 10%.

By selecting the base cloth so as to satisfy this condition, sufficient strength at the joint J can be obtained. As an optimal selection method, both base cloths should satisfy the above conditions.

For reference, FIG. 3 shows JIS L-10.
9 shows a strength-elongation curve obtained by a tensile test (200 mm between chucks and a pulling speed of 100 mm / min) specified in No. 96. The maximum strength is a yield point at which the elasticity is substantially lost, and the strength at break is a strength at a break point at which a break occurs when a tensile force is further applied from the maximum strength. In the present invention, as described above, it is important that the difference between the elongation at maximum strength and the elongation at break is less than 10%.

In particular, in the artificial turf which is tufted in a combination of the first base cloth described in the second embodiment as the upper base cloth and the second base cloth as the lower base cloth and then backed with latex, By setting the upper and lower base cloths under the following conditions, the difference between the elongation at maximum strength and the elongation at break as shown in FIG. A degree curve is obtained.

That is, for the upper base cloth, the JIS
L-1096 tensile test (20 between chucks)
0 mm, tensile strength 100 mm / min), the maximum strength in the vertical and horizontal directions is 490 N / 50 mm width (5
(0 kgf / 50 mm width) or more, and the elongation is preferably 18% or less.

For the lower base cloth, the amount of synthetic resin flocculent was 30 to 70 g / m ² , and the lower base cloth was subjected to a tensile test (200 mm between chucks) specified in JIS L-1096. , Pulling speed 100mm / mi
n) the maximum strength in the longitudinal and transverse directions is 196 N /
It is preferably at least 50 mm width (20 kgf / 50 mm width). In addition, punching is preferable as a method of attaching the cotton-like material.

According to this combination, the backing material adhered to the lower base cloth impregnates the cotton-like material between the upper base cloth and the lower base cloth, so that the two base cloths are integrated. The difference between the maximum strength and the elongation at break in the strength-elongation curve in the tensile test (200 mm between chucks, pulling speed 100 mm / min) specified in -1096 becomes small. As a result, the stress distribution is also equalized in the joint portion, and the bonding strength is increased.

The amount of cotton-like material adhering to the lower base fabric is 30 g /
m is less than ² instead of impregnation amount of back-fastened member is enough, the integration of the upper base cloth and the lower base fabric is difficult. On the other hand, if the amount of the cotton-like material is more than 70 g / m ² , the amount of the backing material impregnated is sufficient, but the amount of the cotton is too large, so that the adhesion to the upper base cloth becomes insufficient. It is not preferable.

The artificial turf for sand is generally manufactured by tufting. Conventionally, the interval (gauge) in the direction orthogonal to the tuft direction is 5/16 inch (about 8 mm), but recently, for soccer fields and baseball fields,
It has been practiced to include elastic particles such as rubber chips in the particles.

Generally, the particle size of the elastic granular material is 0.5 to 3 m.
m, the particle size of the sand is larger than 0.6 to 1.0 mm. Therefore, in the present invention, by setting the gauge to 10 mm or more, the work of filling granular material including elastic granular material into the grass can be easily performed.

When the gauge is increased, the anchor effect of the base material and the adhesive of the Jonite tape on the adhesive decreases, and the dimensional stability of the artificial turf deteriorates accordingly. However, especially in the artificial turf according to the second embodiment, since the upper base cloth and the lower base cloth are integrated, the dimensional stability is good, and the expansion in the oblique direction is small, so that no problem occurs even if the gauge is increased.

Further, according to the second embodiment, in addition to the back stitch (the convex portion of the pile having an anchor effect formed on the back side of the lower base fabric by the tuft), a backing material is provided on the back side of the lower base fabric. Since the unevenness is formed, an anchor effect can be expected also in this portion, and the adhesion strength of the Jonite tape to the adhesive is enhanced.

[0046]

EXAMPLES Examples of the present invention and comparative examples will be described. First, artificial turf was prototyped to have a size of 200 m ² as Examples 1 to 3 and Comparative Examples 1 to 5, respectively.
The pile and tuft specifications for each example are as follows. Pile; nylon split yarn 8000 decitex (dtex) Tuft; pile height 50 mm, gauge 5/8 inch (about 16 mm), basis weight 1200 g / m ²

Example 1 Upper base cloth; polypropylene plain woven cloth (length 550 dtex ×
25 bases, 1100 dtex x 15 bases) Lower base cloth; base cloth with cotton (cotton; 30 dtex, fiber length 100 mm, cotton amount 100 g) with cotton-like material adhered to the upper base cloth
/ M ² ) Backing material; SBR latex coating amount 800 g (DR
Y)

Example 2 Upper base cloth; polypropylene plain woven cloth as in Example 1 Lower base cloth; non-woven fabric (cotton; 40 dtex, fiber length 100 m)
m, weight 150 g / m ² ) Backing material: Same as in Example 1 above, SBR latex coating amount 800 g (DRY)

<Example 3> Upper base cloth; polypropylene plain woven cloth as in Example 1 Lower base cloth: Cotton-based base cloth (cotton; 30 dtex, fiber) obtained by attaching a cotton-like material to the upper base cloth of Example 1 100mm long, 1 cotton
50 g / m ² ) Backing material: Same as in Example 1 above, SBR latex coating amount 800 g (DRY)

<Comparative Example 1> Upper base cloth; polypropylene plain woven cloth as in Example 1 Lower base cloth: Cotton-based base cloth (cotton; 15 dtex, fiber) obtained by adhering a cotton-like material to the upper base cloth of Example 1 80mm long, cotton 10
0 g / m ² ) Backing material: Same as in Example 1 above, SBR latex coating amount 800 g (DRY)

<Comparative Example 2> Upper base cloth; polypropylene plain woven cloth as in Example 1 Lower base cloth: Cotton-based base cloth (cotton; 15 dtex, fiber) obtained by adhering a cotton-like material to the upper base cloth of Example 1 80mm long, 20 cotton
g / m ² ) Backing material: Same as in Example 1 above, SBR latex coating amount 800 g (DRY)

<Comparative Example 3> Upper base fabric; polypropylene plain woven fabric as in Example 1 Lower base fabric; non-woven fabric (cotton; 30 dtex, fiber length 80 mm,
Weight: 150 g / m ² ) Backing material: SBR latex as in Example 1 800 g (DRY)

<Comparative Example 4> Upper base cloth; polypropylene plain woven cloth as in Example 1 above Lower base cloth; not used Backing material; SBR latex as in Example 1 800 g (DRY)

<Comparative Example 5> Upper base cloth; polypropylene plain woven cloth as in Example 1 Lower base cloth: Cotton-based base cloth (cotton; 30 dtex, fiber) obtained by adhering a cotton-like material to the upper base cloth of Example 1 100mm long, cotton 5
0 g / m ² ) Backing material; SBR latex coating amount 900 g (DR
Y)

Next, the above Examples 1 to 3 and Comparative Example 1
A sample having a width of 50 mm and a length of 300 mm was cut out of each artificial turf along the longitudinal direction and the lateral direction from each artificial turf, and subjected to a tensile test (200 mm between chucks, tensile strength specified in JIS L-1096). Speed 100mm /
min), the maximum strength in the longitudinal direction and the elongation at that time, the breaking strength in the vertical direction and the elongation at that time, the maximum strength in the transverse direction and the elongation at that time, the breaking strength in the horizontal direction and the elongation at that time are measured did.

Further, the above Examples 1 to 3 and Comparative Example 1
From each artificial turf, samples of 50 mm wide and 200 mm long were cut out in two pieces each along the vertical and horizontal directions, and as shown in FIG. 5, the two pieces of artificial turf 3, 3 were glued together. The joint was made with a joint tape 7 having 7a. (Joint tape 7; polyester tape 0.4 mm thick, width 50, length 300 mm. Adhesive 7a; urethane-based one liquid,
Width 50mm, length 250mm, application amount 800g /
m ² . ) After curing at room temperature for one week, JIS L-10
The longitudinal strength and the transverse strength of the joint portion were measured by a tensile test specified in No. 96 (300 mm between the chucks and a pulling speed of 100 mm / min). The results are as follows.

Example 1 Maximum strength in the vertical direction: 833 N / 50 mm width (85 kg
f / 50 mm width), elongation at that time 12% Longitudinal breaking strength; 245 N / 50 mm width (25 kg
f / 50 mm width), elongation at that time: 20% (difference between elongation at maximum strength in the longitudinal direction and elongation at break strength: 8%) Maximum strength in the transverse direction: 784 N / 50 mm width (80 kg)
f / 50 mm width), elongation at that time 9% Transverse strength; 294 N / 50 mm width (30 kg
f / 50 mm width), elongation at that time 17% (difference between elongation at maximum strength in transverse direction and elongation at break strength 8%) Longitudinal strength of joint part: 666.4 N / 50 mm width (68 kgf)
/ 50mm width) Lateral strength; 637N / 50mm width (65kgf / 5
0mm width)

Example 2 Maximum strength in the vertical direction: 852.6 N / 50 mm width (87
kgf / 50 mm width), elongation at that time 10% Longitudinal breaking strength: 364.6 N / 50 mm width (27
kgf / 50 mm width), elongation at that time 17% (difference between elongation at maximum strength in the vertical direction and elongation at break strength 7%) Maximum strength in the horizontal direction: 764.4 N / 50 mm width (78
kgf / 50 mm width), elongation at that time 6% Transverse breaking strength; 245 N / 50 mm width (25 kg
f / 50 mm width), elongation at that time 15% (difference between elongation at maximum strength in transverse direction and elongation at break strength 9%) Longitudinal strength of joint part: 607.6 N / 50 mm width (62 kgf)
/ 50mm width) Lateral strength; 627.2N / 50mm width (64kgf
/ 50mm width)

Example 3 Maximum strength in the vertical direction; 950.6 N / 50 mm width (97
kgf / 50 mm width), elongation at that time: 14% Longitudinal breaking strength; breaking at the time of the maximum strength described above (therefore, the difference in elongation between the maximum strength and the breaking strength in the vertical direction is 0).
%) Maximum strength in the lateral direction; 940.8 N / 50 mm width (96
(kgf / 50mm width), elongation 9% at that time Breaking strength in the transverse direction; breaking at the time of the maximum strength described above (therefore, the difference in elongation between the maximum strength and the breaking strength in the horizontal direction is also 0%). Directional strength: 803.6 / 50mm width (82kgf /
50mm width) Lateral strength: 774.2N / 50mm width (79kgf)
/ 50mm width)

Comparative Example 1 Maximum strength in the longitudinal direction: 823.2 N / 50 mm width (84
kgf / 50 mm width), elongation at that time: 14% Longitudinal breaking strength: 245 N / 50 mm width (25 kg
f / 50 mm width), elongation at that time: 24% (difference between elongation at maximum strength in the longitudinal direction and elongation at break strength: 10%) Maximum strength in the transverse direction: 764.4 N / 50 mm width (78)
kgf / 50 mm width), elongation at that time 9%, transverse breaking strength; 235.2 N / 50 mm width (24
kgf / 50mm width), elongation at that time 20% (difference between elongation at maximum strength in transverse direction and elongation at break strength 11%) Longitudinal strength of joint part: 460.6N / 50mm width (47kgf)
/ 50mm width) Lateral strength; 441N / 50mm width (45kgf / 5
0mm width)

Comparative Example 2 Maximum strength in the longitudinal direction: 803.6 N / 50 mm width (82
kgf / 50 mm width), elongation at that time 15% Longitudinal breaking strength: 284.2 N / 50 mm width (29
kgf / 50 mm width), elongation at that time 27% (difference between elongation at maximum strength in the longitudinal direction and elongation at break strength 12%) Maximum strength in the transverse direction: 744.8 N / 50 mm width (76
kgf / 50 mm width), elongation at that time 8% Transverse breaking strength: 294 N / 50 mm width (30 kg
f / 50 mm width), elongation at that time 19% (difference between elongation at maximum strength in transverse direction and elongation at break strength 11%) Longitudinal strength of joint part: 450.8 N / 50 mm width (46 kgf)
/ 50mm width) Lateral strength: 470.4N / 50mm width (48kgf
/ 50mm width)

Comparative Example 3 Maximum strength in the longitudinal direction: 872.2 N / 50 mm width (89
kgf / 50 mm width), elongation at that time 12% Longitudinal breaking strength: 215.6 N / 50 mm width (22
kgf / 50 mm width), elongation at that time: 24% (difference between elongation at maximum strength in the vertical direction and elongation at break strength: 12%) Maximum strength in the horizontal direction: 803.6 N / 50 mm width (82
kgf / 50 mm width), elongation at that time 7% Transverse strength; 323.4 N / 50 mm width (33
kgf / 50 mm width), elongation at that time 21% (difference between elongation at maximum strength in transverse direction and elongation at break strength 14%) Longitudinal strength of joint part: 401.8 N / 50 mm width (41 kgf)
/ 50mm width) Lateral strength; 441N / 50mm width (45kgf / 5
0mm width)

Comparative Example 4 Maximum strength in the vertical direction: 921.2 N / 50 mm width (94
kgf / 50 mm width), elongation at that time: 14% Longitudinal breaking strength; breaking at the time of the maximum strength described above (therefore, the difference in elongation between the maximum strength and the breaking strength in the vertical direction is 0).
%) Maximum strength in the lateral direction; 852.6 N / 50 mm width (87
(kgf / 50mm width), elongation 9% at that time Breaking strength in the transverse direction; breaking at the time of the maximum strength described above (therefore, the difference in elongation between the maximum strength and the breaking strength in the horizontal direction is also 0%). Directional strength; 490 / 50mm width (50kgf / 50
509.6N / 50mm width (52kgf)
/ 50mm width)

Comparative Example 5 Maximum strength in the longitudinal direction: 940.8 N / 50 mm width (96
kgf / 50 mm width), elongation 16% at that time Breaking strength in the longitudinal direction; breaking at the time of the maximum strength described above (therefore, the difference in elongation between the maximum strength and the breaking strength in the vertical direction is 0)
%) Maximum strength in the lateral direction; 921.2 N / 50 mm width (94
kgf / 50mm width), elongation 8% at that time Breaking strength in the transverse direction; breaking at the time of the maximum strength described above (therefore, the difference in elongation between the maximum strength and the breaking strength in the transverse direction is also 0%)
Longitudinal strength; 490 / 50mm width (50kgf / 50
509.6N / 50mm width (52kgf)
/ 50mm width)

Table 1 summarizes the results of each of the above examples.
In Examples 1 and 2, since the difference between the maximum strength and the elongation at break strength was small, the bonding strength of the joint was also 490 N / 50.
mm width (50 kgf / 50 mm width) or more. Comparative Example 1
In Nos. 3 to 3, since the difference in elongation between the maximum strength and the breaking strength is large, the bonding strength of the joint portion is also low. Example 3 and Comparative Example 5 were broken at the maximum strength, and the upper and lower base fabrics were integrated. In Comparative Example 4, the backing material was applied to the woven cloth as the upper base cloth without the lower base cloth, but since the unevenness was smaller than in the other examples, the anchor effect at the joint portion was small and the strength was reduced. In Comparative Example 5, a large amount of latex was applied, and a large amount of latex remained on the back surface. As a result, the anchor effect at the base fabric portion (non-joint portion) was small, and the adhesive strength was slightly reduced.

[Table 1]

Next, as shown in FIG. 1, a sample having a width of 50 mm and a length of 400 mm in a 45 ° direction with respect to the tuft direction was obtained from each of the artificial grasses of Examples 1 to 3 and Comparative Examples 1 to 5 above. And a tensile test (300 mm between chucks, a pulling speed of 10) specified in JIS L-1096.
(0 mm / min), a load was applied to 196 N (20 kgf), and the elongation (dimensional stability) was measured. The results are as follows.

Example 1 Elongation 24% << Example 2 >> Elongation 8% << Example 3 >> Elongation 20% <Comparative Example 1> Elongation 19% <Comparative Example 2> Elongation 21% <Comparative Example 3> Elongation 7 % <Comparative Example 4> Elongation 30% <Comparative Example 5> Elongation 17%

After the elongation test was performed, the artificial turf of each of Examples 1 to 3 and Comparative Examples 3 and 4 was actually laid to construct a futsal coat shown in FIG. FIG. 7 shows a partial cross section of this futsal coat. The base 5 is crushed stone C40 with a thickness of 150 mm, the pile 2 is nylon split yarn 8000 dtex and the length is 50 mm, the filled granular material 6 is two layers and the lower layer 6a is silica sand (particle diameter 0.6 to 1.0).
mm, thickness 15 mm), and the upper layer 6b was a rubber chip (particle diameter 1 to 3 mm, thickness 15 mm). Regarding the laying, two artificial grasses of the above-mentioned Examples 1 to 3 and Comparative Examples 3 and 4 each having a length of 40 m and a width of 2 m were prepared, laid side by side, and then laid by the method of FIG.
All were jointed into one.

After using the futsal coat for one year, the state of breakage of the joint portion was confirmed at the T portion shown in FIG. 6, and the bending of the line was observed at the goal line GL. In Example 2 (dimensional stability 8%) and Example 3 (dimensional stability 20%), no line bending was observed. In Example 1 (24% dimensional stability), slight line bending was observed. In Comparative Example 3 (dimensional stability: 7%), the line was not bent, but joint puncture occurred frequently. In Comparative Example 4 (30% dimensional stability), the line was greatly bent, and joint puncturing was also observed in part.

[0070]

As described above, according to the present invention,
In artificial turf which is laid on the ground by planting piles in the base cloth and filling granular materials between the piles,
The elongation of the base fabric in the 45 ° direction with respect to the pile installation direction is a tensile test specified in JIS L-1096 (300 mm between chucks, pulling speed 100 mm / min).
196N / 50mm width (20kgf /
By setting the elongation under a load of (50 mm width) to 25% or less, the elongation of the artificial turf due to the application of an external force can be effectively suppressed, and line bending can be prevented.

In the case where the base cloth is made of two upper and lower base cloth laminates, a tensile test (200 mm between chucks, a pulling speed of 1 mm) specified in JIS L-1096 of the base cloth laminate is performed.
The maximum strength on the strength and elongation curves in the longitudinal direction and the transverse direction at a speed of 588 N / 50 mm width (60 k / min.
gf / 50 mm width) or more, and the difference between the elongation at the maximum strength and the elongation at break is set to less than 10%, whereby a decrease in the strength of the joint portion can be prevented.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a 45 ° direction with respect to a tuft direction according to the present invention.

FIG. 2 is an essential part cross-sectional view of an artificial turf for describing a problem to be solved by the present invention.

FIG. 3 is a graph showing an example of a strength-elongation curve of a tensile test specified in JIS L-1096.

FIG. 4 is a graph showing a strength-elongation curve of an artificial turf obtained by impregnating a cotton-like material between an upper base cloth and a lower base cloth with a backing material.

FIG. 5 is a sectional view of a main part of an artificial turf showing an embodiment of the present invention.

FIG. 6 is a plan view schematically showing a futsal court constructed with artificial turf of each of Examples and Comparative Examples of the present invention.

FIG. 7 is a partial cross-sectional view illustrating the structure of the futsal court.

FIG. 8 is a cross-sectional view showing a general joint portion of a conventional artificial turf.

FIG. 9 is an explanatory diagram for explaining a line bend occurring in a conventional artificial turf taking a soccer field as an example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base cloth 2 Pile 3 Artificial turf 5 Base 6 Granular material 7 Joint tape 7a Adhesive

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2D051 AB04 AE04 AE05 AF01 AG03 AG15 AG19 AH02 AH03 HA02 HA06 HA08 4F100 AJ04 AK07 AK73 AT00A AT00C BA03 BA07 BA10B BA10C DE01B DG11 DG11A DG11C DG16 A01B04 A01A04A BA03 CA04 CB01 CC16 DA00 EA22

Claims (6)

[Claims] 1. An artificial turf laid on a ground by planting a pile in a base cloth and filling a granular material between the piles, wherein the base cloth in the pile laying direction after the pile is laid. The elongation in the 45 ° direction is the tensile test specified in JIS L-1096 (300 mm between chucks, tensile speed 1
00mm / min), 196N / 50m
25m width (20kgf / 50mm width) load elongation is 25
% Artificial grass. 2. A tensile test (chuck) specified in JIS L-1096 when the base cloth includes upper and lower base cloths and a backing material for the planted pile is provided. 200mm, 100mm pulling speed
/ Min) is 588 N / 50 mm width (60 kgf / min.) On the longitudinal and transverse strength elongation curves.
The artificial turf according to claim 1, wherein the difference between the elongation at the maximum strength and the elongation at break is less than 10%. 3. The method according to claim 2, wherein the base cloth includes upper and lower base cloths, and a backing material for the planted pile is provided. JIS L
Tensile test specified in -1096 (200m between chucks)
m, the maximum strength in the vertical and horizontal directions at a tensile speed of 100 mm / min is 490 N / 50 mm width (50 k
gf / 50 mm width) and an elongation of 18% or less, and 30 to 70 g of synthetic resin cotton-like material is adhered to the lower base fabric per square meter.
Tensile test specified in -1096 (200m between chucks)
m, the maximum strength in the vertical and horizontal directions at a tensile speed of 100 mm / min is 196 N / 50 mm width (20 k
gf / 50 mm width) or more. 4. The artificial turf according to claim 1, wherein the pile is planted on the base fabric by tufting, and a gauge of the pile is 10 mm or more. 5. The artificial turf according to claim 1, wherein the granular material includes a soft granular material. 6. An artificial turf stadium, on which the artificial turf according to claim 1 is laid.