JPH05171611A - Artificial turf with granules and manufacture of granules - Google Patents

Abstract

PURPOSE:To improve the durability of artificial turf without causing of hardening and scattering of dust by using granules of a polyhedron (nonspherical) form having round edge portions which are formed by baking or crushing process, which are to be packed into the turf leaves. CONSTITUTION:Granules 4 to be packed into artificial turf leaves 3 are formed from glass grains of a nonsphetical polyhedron form having round edges and corners or by mixing the grass grains with other inorganic grains. The glass granules 4 used are ones having round edge and corners as well as smoothened surfaces which are formed by crushing or baking process. Since the glass granules can form the surface free of hardening and dusting phenomena, the artificial turf having excellent wear resistance and excellent durability can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an artificial turf containing granules, and a method for producing granules to be filled in the grass of the artificial turf.

[0002]

2. Description of the Related Art A synthetic resin fiber such as polypropylene, polyamide, or polyvinylidene chloride is planted on a woven fabric, and artificial turf is piled from the back side with synthetic rubber or the like. When making a baseball field or the like, it is known that the cushioning performance and catches such as spikes can be made closer to those of natural grass by filling the grass with a granular material such as sand.

In such artificial turf, natural sand such as hill sand and river sand has been generally used as a granular material for filling the inside of the turf, but some of them are spherical glass particles. It has also been proposed to use artificial particles such as (for example, Japanese Utility Model Laid-Open No. 58-46371).

[0004]

By the way, in such an artificial turf containing granular material, when natural sand is used, the sand is destroyed in places where it is frequently used or where strong force is applied. Solidification phenomenon occurs. That is, the fine particles due to breakage flow into the gaps of the sand, the movement of the sand is restricted, and the fine particles are hardened by being kneaded with the abrasion material of grass and other viscous substances. For example, on the footpath of a golf course, the solidification phenomenon is remarkable due to repeated piercing with a metal spike. Similarly, in the tee ground as well, the solidification phenomenon occurs by repeatedly piercing the tee, but in this tee ground, the piercing of the tee must be easy, and strict conditions are required for such solidification. ..

Further, since the sand has horns, the turf leaves are damaged and fibrillation is likely to proceed, and the bleaching phenomenon and abrasion are quick. Similarly, not only the wear of the balls and shoes is fast, but also the slip characteristics are not good in play, and there is a risk of being caught, which is dangerous.

Further, indoors, scattering of sand abrasion powder is not preferable for health. There is almost no sharp sand that causes such problems, and even if there is, the resources are exhausted and it is extremely difficult to obtain.

On the other hand, when spherical glass particles are used, the above-mentioned problems are solved, but in the spherical glass particles based on the conventional proposal, the spherical glass particles facing the surface layer between the lawn leaves are not formed. Forms a very slippery surface. Especially on sloping ground or even on flat ground, it is extremely dangerous in case of rain.

The present invention has been made in view of the above circumstances, and provides an artificial turf containing granules and a method for manufacturing the granules to be filled in the artificial turf, which solves the above-mentioned problems at once. Has a purpose.

[0009]

In order to achieve the above object, in the artificial turf containing granules of the present invention, in the artificial turf in which the granules are filled in the turf eyes, at least the filling layer of the granules is used. A range of a predetermined thickness from the surface, a single layer of glass particles, or formed with a mixture layer of glass particles and other inorganic particles, the shape of the glass particles, each particle is a polyhedron , And the corners and edges of this polyhedron are rounded.

Further, the method for producing the artificial turf-filling granules of the present invention is a polyhedral glass particle obtained by roughly crushing a glass crushed material and then finely crushing the crushed material so that it falls within a predetermined particle size range. Is characterized by rounding the corners of its corners and edges by a firing process.

Here, instead of the firing step in this manufacturing method, the corner portion and the edge portion can be rounded by using a ball mill in the fine pulverizing step.

[0012]

The shape of the glass granules according to the present invention, which is a shape feature in which each corner and edge of the polyhedron is rounded, eliminates slipperiness, which is a drawback of using conventional spherical glass particles. At the same time, it eliminates sharp edges like natural sand, gives proper slipping without catching shoes and spikes during play, and also has the function of reducing grass wear and abrasion of balls and shoes.

Further, since the glass granules of the present invention in which the corners and the edges are rounded are less likely to cause chipping of the corners and the like due to an external force, unlike ordinary silica sand, the broken powder is not contained in the granules. Solidification phenomenon and dust scattering due to intrusion are eliminated or alleviated.

In order to produce glass granules having such a shape, first, a crushed material made of glass is coarsely crushed and then finely crushed to produce a crushed glass product having a desired particle size range. The sharp corners and corners present at the stage are melted and rounded from the sharp parts by firing.

When a ball mill is used in the fine pulverization step, the corners and corners of the crushed glass product crushed by impact are worn away by the crushing action of the balls, similar to the case where the firing step is provided. A polyhedron with sharp corners is obtained.

[0016]

EXAMPLE FIG. 1 is a partial sectional view showing the structure of an artificial turf containing granules according to an example of the present invention. A base 1 made of asphalt or the like is placed on the ground G, and an artificial grass body is placed on the base 1 via an underpad 7. As the underpad 7, a sheet-shaped one in which a rubber chip is hardened with urethane or the like, a polyethylene foam sheet or the like is used.

The artificial turf body is composed of a base layer 2 and an artificial turf leaf 3 planted on the surface thereof. That is, the base layer 2 is composed of, for example, a front surface side base cloth made of polypropylene or the like and a rubber backing part on the back side thereof, and a synthetic resin lawn leaf 3 made of polypropylene or polyamide is planted on the surface of the base cloth. Then, the back surface of the base cloth is piled with rubber latex to form an artificial grass body.

Within the grass pattern of the grass leaf 3, there is formed a glass particle layer 4 in which a large number of glass particles are uniformly filled. It is preferable that the thickness of the glass granular material layer 4 is smaller than the height of the grass leaf 3 by about several mm, for example, about 2 mm.

The shape of the glass particles used in the glass particle layer 4 is as shown in the enlarged view of FIG.
It is a non-spherical polyhedron, and its corners and edges are rounded. And
The particle size distribution of this glass granule is 0.
2 mm to 2.0 mm, more preferably 0.5 mm to 1.
It is about 5 mm.

In this embodiment, the material of the glass granules is ordinary soda lime glass used for beer bottles and the like. In order to obtain such glass granules, first, for example, a beer bottle or the like is used as a crushing material, and after roughly crushed to a size of several mm or several tens of mm by an appropriate coarse crusher such as an impeller breaker or a jaw crusher,
The crushed product is finely pulverized by a cone crusher, a roll crusher, a hammer mill, a ball mill or the like, and adjusted to a desired particle size range by using a sieve or the like. In this state, the crushed product is a polyhedron as shown in its enlarged external view in FIG. 3, but there are cases where many sharp corners are left at its corners and edges.

Therefore, next, such a crushed product is fired. This firing step rounds the corners and corners of the crushed product. The firing conditions are, for example, when a horizontal furnace is used, the heating temperature is 650 ° C to 1100 ° C,
The holding time is 1 to 5 minutes, depending on the heating temperature. More preferably, the heating temperature is 750 ° C to 850 ° C,
The holding time is about 4 to 5 minutes.

If the heating temperature is too high, or if the holding time is too long in relation to the heating temperature, not only the glass particles melt and mutual fusion occurs, but also the whole becomes spherical, which is not preferable.

Here, in order to improve the productivity, it is preferable to add a buffer material for the purpose of preventing mutual adhesion during the firing.

Glass particles of the same shape can be obtained by passing the above-mentioned crushed product through the furnace at a heating temperature of 1200 ° C. or higher using a vertical furnace. Furthermore, when a ball mill is used in the fine crushing process and the crushing function of the balls is utilized to crush under such conditions that this function is enhanced, the crushed product gradually removes sharp corners at its corners and edges. The glass particles with sharp corners as shown in FIG. 2 can be obtained without providing a firing step.

The glass granules obtained as described above had a compressive fracture strength of 20 kg / mm ² , which was 4 to 5 times or more that of ordinary silica sand. Now, in the artificial turf with granules shown in FIG. 1 having the glass granule layer 4 using the glass granules as described above, as is clear from the experimental results described later, the glass granules have Due to its size, it is not destroyed even after long-term use, has little dust, and is hard to solidify.

Also, due to the shape of the glass granules used in the same manner, there is little possibility of catching spikes or the like and damage to the grass blades 3 or balls, and at the same time, even if the glass granules are raised on the surface layer of the grass blades 3, they are spherical. The friction coefficient of the surface layer is not extremely reduced as compared with the case of using the glass granules described in (1) above, and a proper slip is given to the play.

In the example shown in FIG. 1, the glass granule layer 4 made of a single glass granule is formed in the lawn leaf 3, but the present invention is not limited to this, and a partial sectional view is shown in FIG. As described above, even if the mixed layer 5 of the glass granules and the other inorganic granules is formed, almost the same effect can be obtained as is clear from the experimental examples shown below.

Further, as shown in a partial cross-sectional view in FIG. 5, as the granular material layer in the turf leaf 3, the glass granular material layer 4 or the mixed layer 5 as described above is the upper layer, and below the ordinary silica sand. You may provide the lower layer 6 which consists of arbitrary granular materials which make these etc. a main component. In this case, the sliding performance of the artificial turf surface layer, the damage to the balls and the like are the same as those in FIG. 1 or 4, and the solidification or the influence on the turf leaf 3 is also affected by the external force, or Since it is mainly the upper layer that is moved by an external force or the like, almost the same effect can be obtained. Of course, in the example of FIG. 5, it is possible to use the mixed layer 6 as the lower layer 6.

Table 1 below shows the results obtained by experiments for the difference in various performances due to the difference in the granular material layer formed in the grass of the grass 3. In this experiment, the structure was the same except for the granular material layer, and the grass was made of polypropylene and had a length of 25 mm, and the total thickness of the granular material layer was 23 mm. Then, after forming the granular layer, various performances were investigated 2 weeks and 8 months later.

[0030]

[Table 1]

The relationship between the test No. in Table 1 and the type of granular material layer is as follows. No. 1: In the embodiment shown in FIG. 1 of the present invention, each corner portion and edge portion of the polyhedron is rounded and the grain size is 0.5 mm to
Using the glass particle layer 4 using 100% of 1.8 mm glass particles No. 2: In the example shown in FIG. 4 of the present invention, 37.5% of the above glass particles, silica sand (particle size 0.2-1.8 mm) 6
Using 2.5% of mixed layer 5 No. 3: In still another embodiment of the present invention, the same as the upper layer (5 mm) using 100% of the glass granules of No. 1 described above and N
Laminated lower layer (18 mm) of the mixture of o.2 No. 4: Conventional example using 100% silica sand (particle size 0.2 to 1.8 mm) No. 5: Spherical glass particles # 30 (particles Diameter 0.5 to 0.71
(mm) 100% of the glass granule layer is used for Comparative Example No. 6: 37.5% of spherical glass particles # 30 and 62.5% of silica sand (particle diameter 0.2 to 1.8 mm). Comparative Example Using Mixed Layer In this Table 1, "hardness" is a sensory test based on the easiness of piercing a golf tee and the like. "Slip" is also a sensory test,
Tested by putting on tennis shoes for hard courts and sliding on artificial turf. ○ is a suitable slip, × is too slippery and dangerous, and △ is in the middle. "Hardness" indicates a range of local hardness measurement values over a plurality of points by the Kasuga hardness meter CS type.

As is clear from the above experimental results, as compared with the conventional example using natural silica sand, the glass granule layer is shown as an upper layer in FIG. 1 and FIG. 4 and the glass granule mixed layer is as a lower layer. In each of the examples of the present invention, it was confirmed that it is difficult to solidify particularly after a long period of time, and is excellent in terms of slippage as compared with Comparative Examples using spherical glass particles, in a dry state, It was confirmed that in any of the wet conditions, it would not slip too much as in the case of using spherical glass particles and would not be in a dangerous condition.

Further, as shown in Table 1, the resilience of various balls was not particularly problematic, and it was confirmed that the ball can be used sufficiently in various competitions. In addition, in the present invention, the structure excluding the granular layer, for example, the type and shape of the turf and the base layer, or the structure of the base, etc. is not limited at all, and these are appropriately selected according to the target competition. Should be selected for.

Further, as the material of the glass granules, in addition to those used for beer bottles as described above, those having the following composition are particularly suitable for the use of the present invention. SiO ₂ and Al ₂ O ₃ 60-90% Na ₂ O and K ₂ O 5-20% CaO and MgO 5-20% Further, as a crushing agent for obtaining the glass granules of the present invention, beer bottles, It goes without saying that any plate glass or the like can be used.

[0035]

As described above, according to the present invention,
A glass granule layer having a shape in which each corner portion and edge portion of the polyhedron is rounded over at least the surface predetermined thickness of the granules filled in the grass grain, or such a glass granule and other inorganic grain state Since the mixed layer is provided, the compressive crush strength of the glass granules is strong, so that the glass granules are unlikely to be crushed even when used for a long time, and the solidification phenomenon is unlikely to occur.
As a result, when used on a golf course, good piercing properties of the tee can be maintained for a long period of time.

Further, since the corners and edges of the glass granules are rounded, grass blades and floor materials (base layers) are not damaged by sharp parts such as silica sand, and the abrasion of these is avoided. An artificial turf with improved strength and durability can be obtained. Similarly, the balls, shoes, etc. are not damaged, and their life can be extended. Moreover, since the generation of dust due to the crushing of the corners and the like is small, it is particularly effective for improving the indoor environment.

Further, since the glass granules in the present invention are not spherical but essentially polyhedral, they do not extremely reduce the friction coefficient even if they are raised on the surface layer of the turf leaf, which is dangerous. Not only that, it also gives a proper amount of slip to various plays with little hooking.

Furthermore, when soda lime glass used in ordinary beer bottles and the like is used as the material for the glass granules, by filling the entire surface of the artificial turf with the surface area, acid rain is prevented. It also has a large neutralizing effect, and can be expected to have a good effect on neighboring plants and the like.

Furthermore, the glass granules have the same color not only in the surface portion but also in the whole particle according to the kind of the crushed material, so that the color does not change with time and only the surface is colored. Compared with the case, the original aesthetics will not be impaired. In particular, the amber color used for beer bottles and the like has good compatibility with the green of the turf leaf, and that state is maintained for a long period of time.

[Brief description of drawings]

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

FIG. 2 is an enlarged external view of the glass granules used in the glass granule tank 4.

FIG. 3 is an enlarged external view of a crushed product before rounding corners and edges in the method for manufacturing glass granules shown in FIG.

FIG. 4 is a partial sectional view showing the structure of another embodiment of the present invention.

FIG. 5 is a partial sectional view showing the structure of still another embodiment of the present invention.

[Explanation of symbols]

 1 ... ・ Substrate 2 ・ ・ ・ ・ Base layer 3 ・ ・ ・ ・ ・ ・ Shiba 4 ・ ・ ・ ・ Glass particle layer 5 ・ ・ ・ ・ Mixed layer of glass particles and other inorganic particles 6 ・ ・ ・Lower layer 7 ... Underpad

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toru Nakagawa 1-10-12 Okutenjin-cho, Takatsuki-shi, Osaka

Claims (3)

[Claims] 1. An artificial turf in which a plurality of filaments are planted on a base cloth and the granular material is filled in the turf of the artificial turf in a range of a predetermined thickness from at least the surface of the filling layer of the granular material. Is formed of a single layer of glass granules, or a mixture layer of glass granules and other inorganic granules, and each of the glass granules is a polyhedron, and a corner of the polyhedron. An artificial turf containing granules, characterized in that the part and the edge part have a rounded shape. 2. A method for producing a granular material to be filled in the turf of artificial turf, which is obtained by roughly crushing a glass crushed material and then finely crushing it so that it falls within a predetermined particle size range. A method for producing a granule for filling artificial grass, characterized in that the corners and corners of the polyhedral glass particles are rounded by a firing step. 3. A method for producing a granule for filling artificial grass, characterized in that a ball mill is used in the finely pulverizing step instead of the firing step to round the corner portion and the edge portion.