JPH1193112A - Artificial turf - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a favorable touch without any elastic seals by providing elastic leaves having a rubber-like elasticity at least at a part of artificial turf. SOLUTION: A number of leaves 2 made of a thready polymer are implanted on a base material 1 made of a fibrous base cloth so as to rise upward and form a nearly flat artificial turf face S with the assembled fronts of leaves 2. At least a part of the assembled fronts of leaves 2 is made of elastic leaves 21 having a rubbery elasticity and the rest are made of non-elastic leaves 22 having no rubbery elasticity. When both materials are mixed at a specified ratio, it is preferable that the height of the elastic leaves 21 is made higher by H, about 5 mm for instance, than the non-elastic leaves 22. In this way, horizontal external forces of the artificial turf face S are reduced to prevent shocks, cuts, burns, etc., on sliding.

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 an artificial turf having excellent characteristics such as a feeling of contact with ground and drainage property, and particularly suitable for various sports stadiums.

[0002]

2. Description of the Related Art Artificial turf can withstand continuous use compared to natural turf and is easy to maintain.
It is widely used in tennis courts, soccer fields, baseball fields, and general grounds.

[0003] Here, the artificial turf is formed by implanting or integrally forming a large number of leaf pieces (pile) made of a thread-like polymer on a planar material, for example, a fiber base material, that is, the large number of leaf pieces is a base. It refers to a material that is arranged facing upward from the material, thereby forming an artificial turf surface.

[0004] Various proposals have been made in this type of artificial turf in order to obtain a feeling of grounding more similar to that of a natural turf. According to Japanese Patent Application Laid-Open No. Hei 8-109610 as an example, There has been proposed an artificial turf in which an elastic sheet is bonded to a fiber base cloth as a base material, and a pile is tufted on the elastic sheet side of the base material.

[0005]

According to this, it is described that the elastic sheet can maintain an appropriate ground feeling close to natural lawn for a long period of time, but this kind of elastic sheet has a compression recovery property. Some cushioning functions require relatively low density porous.

[0006] However, such an elastic sheet is
Since a large number of air bubbles formed therein are independent of each other, the water permeability is poor. Therefore, when viewed as an artificial turf as a whole, the feeling of contact with the ground is improved, but the water permeability is significantly poor.

As a problem in manufacturing, not only the number of joining steps for joining an elastic sheet on a fiber base fabric increases, but also
Poor feeding of the base fabric is likely to occur when piles are laid. Furthermore, even if the roll is wound after the pile is planted, the winding diameter becomes large and bulky by the thickness of the elastic sheet, so that the handleability during storage and construction is deteriorated.

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 not only good grounding feeling and good drainage, but also easy manufacture and construction. An object of the present invention is to provide an artificial turf that can effectively reduce horizontal external forces such as sliding.

[0009]

In order to achieve the above-mentioned object, the present invention provides an artificial turf having a large number of leaf pieces made of a thread-like polymer arranged on a flat base material. In the artificial turf having at least one surface, at least a portion of the artificial turf surface is made of an elastic leaf having rubber-like elasticity.

[0010] Here, the rubbery elasticity means that when the tensile force is released at a room temperature after being extended to twice the initial length by a predetermined tensile force, maintaining the state for one minute, and then releasing the tensile force.
It is defined as a tensile set property that shrinks to 160% or less of its initial length within 0 minutes. In the present invention, a leaf piece having such a property is called an elastic leaf piece.

According to this configuration, since the elastic leaf pieces are arranged on the artificial turf surface, a good feeling of ground contact can be obtained. Also,
Since an elastic sheet that inhibits water permeability is not required unlike the above-described conventional example, drainage is good and production and construction can be easily performed. Furthermore, even if the player slides or falls down in a skidding state, the elastic leaf pieces easily deform in the horizontal direction,
The impact force on the player is reduced.

In the present invention, the elastic leaf pieces preferably occupy 10% or more of the artificial turf surface in terms of area, whereby the feeling of contact with the ground is further improved and the external force on the artificial turf surface in the horizontal direction is reduced. The effect becomes more pronounced.

In order to reduce both the frictional resistance of the entire artificial turf surface and the external force applied to the artificial turf surface in the horizontal direction so as not to cause an impact, cut, burn or the like at the time of sliding, at least the elastic leaf piece must be formed. It is preferable that some of them have a height lower than that of the artificial grass surface.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Next, for better understanding of the technical concept of the present invention, an embodiment will be described with reference to the drawings.

As shown in FIG. 1, this artificial turf is planted on a base material 1 made of, for example, a fibrous base fabric such that a large number of leaf pieces 2 made of a thread-like polymer are erected upward. A substantially flat artificial grass surface S is formed by a set of leaf tips of each leaf piece 2.

In the present invention, at least a portion of the leaf pieces 2 forming the artificial turf surface S is composed of elastic leaf pieces 21 having rubber-like elasticity, and the rest is a leaf leaf similar to the conventional one having no rubber-like elasticity. Certain inelastic leaf pieces 22 are used.

That is, the inelastic leaf piece 22 is made of polyethylene, polyvinyl chloride, polyethylene terephthalate (PET), polybutylene terephthalate (PB).
T), synthetic fibers such as polypropylene, polyvinylidene chloride, and nylon may be used, and the shape may be appropriately selected from straight and curled. The fiber type may be either a long fiber or a short fiber, and according to the production method, a monofilament, a multifilament, a tape-like yarn and the like can be mentioned. Further, a material subjected to post-processing such as split processing or crimping can be arbitrarily selected.

Although the entire artificial turf surface S may be entirely made of the elastic leaf pieces 21, the effect of the present invention can be more effectively exerted on the artificial turf surface S with respect to the total surface area. 21 should be 10% or more.

When the elastic leaf piece 21 and the non-elastic leaf piece 22 are mixed at a predetermined ratio, as shown in FIG. 1, the height of the elastic leaf piece 21 is longer than the length of the non-elastic leaf piece 22 by H. For example, it is preferable to lower the height by about 5 mm. According to this, both the frictional resistance of the entire artificial turf surface S and the external force in the horizontal direction with respect to the artificial turf surface S are reduced, and the occurrence of impact, cuts, burns, and the like during sliding can be suppressed.

The height of the elastic leaf piece 21 is changed to the inelastic leaf piece 2.
In order to make the length H lower than 2
When both 1 and 22 are straight piles, it is sufficient to simply make the height of the elastic leaf piece 21 lower than that of the inelastic leaf piece 22, but as shown in FIG. The height of the non-elastic leaf piece 22 may be made lower than that of the non-elastic leaf piece 22, or the non-elastic leaf piece 22 may be made substantially upright, and the elastic leaf piece 21 may be planted so as to fall down. The height may be shorter than the height.

In the example of FIG. 1, the base material 1 is a fibrous base cloth, and the elastic leaf pieces 21 and the non-elastic leaf pieces 22 are mixed and tufted, as shown in FIG. In addition, the present invention also includes a structure in which the substrate 1a and the elastic leaf piece 21a are integrally formed. In addition, in this integrated type, in some cases, the inelastic leaf piece 22 can be tufted between the elastic leaf pieces 21a after the molding.

As a material of the elastic leaf piece 21, for example, elastic fiber such as spandex fiber, thread rubber, composite fiber and the like can be typically mentioned. ing.

The spandex fiber (segmented polyurethane) is also referred to as an elastic fiber, and has a property such that even if it is greatly deformed, it is quickly recovered when released from an external force which causes the deformation. As the material, a block copolymer obtained by reacting a diisocyanate with a macroglycol having a hydroxyl group terminal and a chain extender is used.

The rubber thread is made of high-grade natural rubber or cis.
An elastomer obtained by adding a vulcanizing agent, a stabilizer, an antioxidant, and a pigment to 1,4-polyisoprene and being cross-linked at a high temperature, which is known as an elastic fiber. It is preferred in that respect.

The conjugate fiber is a two-component fiber composed of a hard component and an elastomer component. The hard component is a polyamide or polyester, and the elastomer component is a segmented polymer having a polyurethane or polyester hard segment.

Thermoplastic elastomer (TPE: Ther)
Moplastic Elastomer is plasticized at high temperature like a thermoplastic plastic and can be easily molded. However, since the molded product exhibits rubber-like elasticity at room temperature, it can be used as the elastic leaf piece 21.

The thermoplastic elastomer has a structure in which a soft phase is dispersed in a hard phase (for example, PP (polypropylene) / EP obtained by a dynamic vulcanization method).
DM (ethylene / propylene / diene copolymer) TP
E) and a microphase-dispersed structure in which a hard phase is dispersed in a soft continuous phase represented by SBS (styrene-b-butadiene-b-styrene copolymer). Can be used as

According to the dynamic vulcanization method, PP and EPDM are charged into a kneader at a weight ratio of 40/60,
While kneading at 190 ° C., a vulcanizing agent (sulfur, vulcanization accelerator, peroxide, etc.) is added and kneading is continued. After the kneading torque is maximized, kneading is further continued for 2 to 3 minutes. A PP / EPDM-based TPE is obtained as a dynamic vulcanizate having a two-phase structure in which rubber particles having a diameter of several μm which are almost completely cross-linked are dispersed in a crystalline PP matrix.

SBS has a microphase dispersion structure in which a styrene domain (hard phase) having a diameter of several hundred angstroms is dispersed in a continuous butadiene phase (soft phase). At room temperature, the styrene domain physically acts as a crosslinking point. Therefore, rubber elasticity is exhibited.

Examples of the type of thermoplastic elastomer applicable as the elastic leaf piece 21 include styrene (hard phase:
PS (glass), soft phase: BR, IR, hydrogenated I
R), ester type (hard phase: polyester (crystal), soft phase: polyether, polyester), urethane type (hard phase: polyurethane (crystal, hydrogen bond), soft phase: polyether, polyester), amide type (hard) Phase: polyamide (crystal, hydrogen bond), soft phase: polyether, polyester), fluorinated (hard phase: fluororesin (crystal),
Soft phase: fluoro rubber), olefin type and the like.

The following two-phase structures are included in the olefin series:
That is, (hard phase: PP, PE (crystal), soft phase: EP
DM, IIR), (hard phase: PE (crystal), soft phase: E
VA, EEA, CPE), (hard phase: PE (crystal), ion cluster ... ionomer, soft phase: amorphous PE),
(Hard phase: synd1,2-PB (crystal), soft phase: amorphous PB).

The elastic leaf piece 21 may be formed solely of the above-mentioned polymer having rubber elasticity, or may be combined with an inelastic body having no rubber elasticity.

That is, as shown in FIG. 4, an inelastic body 212 is placed around a polymer body 211 having rubber elasticity.
5, a thread coated with a polymer 211 having rubber elasticity around an inelastic body 212, as shown in FIG. 5, and further shown in FIG. The elastic leaf 21 may be formed by twisting a thread of the polymer 211 having rubber elasticity and a thread of the inelastic body 212.

In the grass of the artificial grass according to the present invention,
A well-known filler such as sand, rubble, or rubber chips may be appropriately filled. Particularly, a filler such as sand, which is a granular material and has low rolling resistance, can further improve the sliding characteristics.

[0035]

EXAMPLE Next, artificial turf was actually produced by changing the ratio of the elastic leaf piece 21 and the inelastic leaf piece 22 and laid on a flat concrete base to evaluate the feeling of grounding, sliding property and drainage property. The evaluation of the manufacturing and workability was performed, and this will be described.

The feeling of contact with the ground was evaluated on a five-point scale based on the feeling of walking and running. The higher the numerical value, the greater the elasticity. Sliding performance is evaluated by feeling when sliding, and the ease of sliding (the higher the score is, the easier it is) and the strain recovery of the artificial turf after sliding (the higher the score, the better the recovery is). Were evaluated on a five-point scale, and the average score of both was used. The drainage property and the production / workability were also evaluated on a five-point scale, and the higher the score, the better.

The tuft conditions were set in both the embodiment and the comparative example.
Ge = 5/16, St = 4.0, and Ph = 30 mm. In addition, the restoration amount of each used leaf piece was measured, and this was a characteristic value applied to the above definition of rubbery elasticity, that is, it was extended to twice the initial length at room temperature, and the state was maintained for 1 minute. And Y / X as a percentage of the initial length X of the length Y contracted within 10 minutes after releasing the tensile force.

Example 1 Elastic leaf pieces (restoration amount: 104%)
Was set to 8, and the ratio of inelastic leaf pieces was set to 92. The elastic leaf pieces and the non-elastic leaf pieces had the same length (no step). Perhaps because of the low elasticity as a whole, the feeling of contact with the ground is 3 points, the sliding property is 3 points, and the drainage property and the manufacturing and construction properties are both 5 points.
Was a point.

Example 2 Elastic leaf pieces (restoration amount: 105%)
Was set to 11, and the ratio of inelastic leaf pieces was set to 89. The elastic leaf pieces and the non-elastic leaf pieces had the same length (no step). Because of the low elasticity as a whole, the feeling of contact with the ground is 3.5 points, the sliding property is 3.5 points, drainage and
The workability was 5 points in each case.

Example 3 Elastic leaf pieces (restoration amount: 106%)
Was 100, that is, the entire artificial grass surface was made into elastic leaf pieces. Because of good elasticity, the feeling of contact with the ground was 5 points, the sliding property was 3 points, and the drainage property and the manufacturing / workability were 5 points.

<< Example 4 >> Elastic leaf pieces (restoration amount: 158%)
Was 100, that is, the entire artificial grass surface was made into elastic leaf pieces. The elasticity was good, the grounding feeling was 5 points, the sliding property was 3 points, and the drainage property and the production / workability were 5 points as in Example 3.

Example 5 Elastic leaf pieces (restoration amount: 108%)
And the ratio of inelastic leaf pieces to 50. The elastic leaf pieces and the non-elastic leaf pieces had the same length (no step). The elasticity was relatively good, the feeling of contact with the ground was 4.5 points, the sliding property was 3 points, and the drainage property and the manufacturing / workability were 5 points.

Example 6 Elastic leaf pieces (restoration amount 109%)
And the ratio of inelastic leaf pieces to 50. In this case, a step was provided on each leaf piece by making the elastic leaf piece 5 mm lower than the non-elastic leaf piece. The elasticity was comparatively good, and, as in Example 5, the feeling of contact with the ground was 4.5 points, the sliding property was the highest 5 points, and the drainage property and the production / workability were 5 points.

Comparative Example 1 Inelastic leaf pieces (restoration amount 165)
%), That is, the entire artificial turf surface was regarded as an inelastic leaf piece. The elasticity was relatively poor, the feeling of contact with the ground was 2 points, and the sliding property was 2 points, but the drainage property and the manufacturing / workability were 5 points.

Comparative Example 2 Inelastic leaf pieces (restoration amount 198)
%), That is, the entire artificial turf surface was regarded as an inelastic leaf piece. The elasticity was poor, the feeling of contact with the ground was at least one point, and the sliding property was at one point, but the drainage property and the manufacturing / workability were both at five points.

Comparative Example 3 As in Comparative Example 2, inelastic leaf pieces (restoration amount 198%) were 100, that is, the entire artificial grass surface was inelastic leaf pieces. The one obtained by bonding an elastic sheet to a fibrous base cloth was used. Therefore, the elasticity was relatively good, and the feeling of contact with the ground was 4.5 points, but the sliding property was 2 points, and the drainage property and the manufacturing / workability were at least 1 point. This is due to the influence of problems at the time of manufacturing, such as poor substrate feed during tufting and an increase in the diameter of the artificial turf winding.

The results are shown in Table 1 in order to prepare comparisons between Examples 1 to 6 and Comparative Examples 1 to 3.

[Table 1]

[0048]

As described above, according to the present invention,
In an artificial turf having an artificial turf surface formed by arranging a large number of thread pieces made of a thread-like polymer on a flat base material, the artificial turf surface has rubber-like elasticity. By using the leaf pieces, a good feeling of ground contact can be obtained without using an elastic sheet as in the conventional example.

In addition to good drainage, production and construction can be performed easily. Furthermore, even if the player slides or falls down in a skidding state, the elastic leaf pieces easily deform in the horizontal direction,
The impact force on the player is reduced.

Further, by making at least a part of the elastic leaf pieces shorter than the artificial grass surface, both the frictional resistance of the entire artificial grass surface and the external force in the horizontal direction with respect to the artificial grass surface are reduced, and the sliding force at the time of sliding is reduced. An impact, cut, burn or the like can be prevented from occurring, and a highly safe artificial grass can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing one embodiment of an artificial lawn according to the present invention.

FIG. 2 is a sectional view schematically showing a modified example of the artificial grass according to the present invention.

FIG. 3 is a sectional view schematically showing another modified example of the artificial grass according to the present invention.

FIG. 4 is a schematic perspective view showing an example of an elastic leaf piece used for the artificial grass of the present invention.

FIG. 5 is a schematic perspective view showing another example of the elastic leaf piece used for the artificial grass of the present invention.

FIG. 6 is a schematic perspective view showing still another example of the elastic leaf piece used for the artificial grass according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Leaf piece 21 Elastic leaf piece 22 Inelastic leaf piece

Claims (3)

[Claims] 1. An artificial turf having an artificial turf surface formed by arranging a large number of leaf pieces made of a thread-like polymer on a planar substrate and facing the substrate upward, wherein at least a portion of the artificial turf surface is An artificial lawn comprising elastic leaf pieces having rubber-like elasticity. 2. The artificial turf according to claim 1, wherein the elastic leaf pieces occupy at least 10% of the artificial turf surface. 3. The artificial turf according to claim 1, wherein at least a part of the elastic leaf piece has a height shorter than that of the artificial turf surface.