JP6849454B2 - Artificial lawn - Google Patents

Description

The present invention relates to an artificial lawn whose usability does not easily change depending on the weather.

Artificial lawns are often used in stadiums where sports such as ball games and athletics are performed, and various artificial lawns have been proposed in which grains are filled between turf threads that imitate the turf leaves and a filling layer is provided. ing.

For example, Patent Document 1 states that a lawn or lawn primary layer of mat is laid on which multiple blades of artificial material are woven to form the blades projecting from one side of the mat that creates the lawn: said blades. A filler placed in between, said filler containing a measurement of coarse product obtained from a raw material based on finely crushed coconut; an artificial lawn containing; said coarse product to finely crushed coconut. By essentially containing a single granular and fibrous portion contained in the base material, the granular and fibrous portion undergoes a step of separating the granular and fibrous portion from the powder portion of the raw material based on finely crushed coconut. The granular and fibrous portions obtained and contained in the coarse product are obtained by sieving the raw material based on finely ground coconut, the granular and fibrous portions up to 90% by weight 500 microns (μm). ) An artificial lawn, characterized by having the above particle size distribution, has been proposed.

Special Table 2010-523855 Gazette

The artificial lawn described in Patent Document 1 is provided so that the particle size distribution of the raw material based on coconut can be adjusted to obtain good drainage and the like, but when the filler is dry and wet. There was a risk that the usability would change significantly depending on when it was present.

The present invention provides an artificial lawn in which the change in usability is small depending on whether the filler is dry in fine weather, wet in rainy weather, or after watering.

In order to achieve the above object, the present invention has the following configuration.
That is, the artificial lawn according to the present invention is an artificial lawn in which turf threads are planted on a base cloth and a filler is filled between the planted turf threads to provide a filling layer.
The filler comprises hard granules, elastic granules and a coconut filler based on natural coconut.
The filling layer is composed of hard grains of 1% or more and 50% or less in volume ratio, coconut filler of 5% or more and 45% or less, and the balance of elastic grains .
The packed bed includes a surface layer and a lower layer arranged so as to be in contact with the bottom of the surface layer. The surface layer contains the elastic particles and the elastic particles are a synthetic resin elastomer, synthetic rubber, or natural rubber. It is made of elastic grains, which are either single or a combination of crushed rubber products.
The palm filler is contained in the lower layer, and the palm filler contained in the filling layer in a volume ratio of 5% or more and 45% or less is not contained in the surface layer, so that the palm filler is on the artificial lawn. It is characterized in that it is difficult to contact the athlete.

According to the artificial lawn according to the present invention, a filling layer filled with a filler is provided between the turf threads planted on the base cloth, and a palm filler based on natural palm is added to the filling layer in a volume ratio of 5. Since it is contained in an amount of% or more, the water contained in the coconut filler evaporates when the temperature rises, and the effect of suppressing the temperature rise due to the heat of vaporization can be suitably obtained.
Further, by setting the coconut filler to 45% by volume or less, it is possible to suppress deterioration of the feel and generation of abnormal noise due to the coconut filler that retains water after watering in rainy weather or artificial lawn.
Further, the filler is dried by containing hard particles in the filler, containing the hard particles in the filler in a volume ratio of 50% or less, and forming the rest of the filler with elastic particles. It is possible to reduce the change in usability between when it is wet and when it is wet.

Further, if the packed bed contains 20% or more of elastic particles in a volume ratio, the change in usability between when the packed bed is dry and when it is wet can be made smaller, which is preferable. ..

Further, if the filling layer is provided with a surface layer and a lower layer to be arranged so as to be in contact with the bottom of the surface layer, and the palm filler is not contained in the lower layer and the surface layer, the artificial lawn is used. It is preferable because the palm filler is less likely to come into contact with the player when playing ball games or other sports above, and the problem that the moisture contained in the palm filler directly wets the player can be reduced.
Further, if the surface layer contains elastic particles, the surface layer is elastically deformed to reduce the deformation of the lower layer even when a force is applied to the surface of the filling layer by sports performed on an artificial lawn. Since the movement of the coconut filler contained in the lower layer to the surface of the packed layer can be suppressed, the coconut filler is less likely to come into contact with the athlete, which is preferable.

According to the artificial lawn of the present invention, it is possible to reduce the change in usability between sunny weather in which the filler is easily dried, wet rainy weather, and after watering.

It is sectional drawing which shows one Embodiment of the artificial lawn which concerns on this invention. It is a table which shows the composition and the evaluation result of the packing layer used for the shock absorption test and the evaluation of the feeling of treading.

An embodiment of the present invention will be specifically described with reference to the drawings.
The foundation layer 1 is formed by casting asphalt concrete or permeable concrete on the ground, and the upper surface is formed as a flat surface.
The foundation layer 1 may be made of a water-permeable material such as water-permeable concrete, and may be provided so as to have water-permeable property and drain rainwater or the like flowing from above downward, or a non-water-permeable material such as asphalt concrete. It may be formed using a material, and a drainage groove or the like may be formed on the upper surface thereof so as to drain rainwater or the like from above in the lateral direction, or may be formed on the ground itself, for example. ..

2 is an artificial lawn.
In the artificial lawn 2, a plurality of turf threads 21 are planted on the front surface side of the base cloth 22, and a backing material 23 for fixing the turf threads 21 is provided on the back surface side of the base cloth 22.
A filling layer 24 filled with a filler is provided between the planted turf threads 21.

In the artificial lawn 2, a polyethylene monofilament turf thread 21 is planted in a cut pile shape on a base cloth 22 using a plain weave woven cloth made of polypropylene to form turf leaves, and the turf leaves are formed on the back surface of the base cloth 22. A backing material 23 such as urethane resin is applied to fix the planted portion of the turf thread 21.
The artificial lawn 2 uses a polypropylene plain weave woven fabric as the base cloth 22, but the present invention is not limited to this, and known materials such as woven fabrics, knitted fabrics, and non-woven fabrics capable of planting turf yarn 21 can be used. ..
Further, the artificial lawn 2 uses a polyethylene monofilament for the turf thread 21, but the present invention is not limited to this, and the thickness, material, shape, etc. of the thread may be appropriately selected and used, for example, a polyethylene split yarn. May be planted as turf thread 21, or turf thread 21 of another material or thickness may be used.

The filling layer 24 is provided in a two-layer structure including a surface layer 24b arranged on the surface of the artificial lawn and a lower layer 24a arranged so as to be in contact with the surface layer 24b.
The filler constituting the filler layer 24 includes hard particles, elastic particles elastically deformed when subjected to an external force, and a coconut filler based on natural palm.
Specifically, the surface layer 24b is composed of only elastic particles, and the lower layer 24a is composed of a mixture of hard particles and a coconut filler.

The packed bed 24 uses styrene resin-based elastomer granules as elastic particles, but is not limited to this, and other synthetic resin elastomers such as olefin resin-based elastomers, synthetic rubber and natural rubber granules, and waste. Recycled products such as crushed rubber products may be used alone or in combination.

The packed bed 24 uses silica sand as the hard particles, but is not limited to this, and hard granules such as pebbles and sand other than silica sand, pottery grains, and resin pellets may be used alone or in combination. Is also good.

The coconut filler uses a crushed natural coconut, and specifically, is a mixture of granules, powder, and fibers obtained by crushing coconut nuts. Even if the size of the granules of the coconut filler is large, it is formed to a size of about 5 mm.

The palm filler retains rainwater, water supplied by sprinkling water, etc., and vaporizes when the temperature rises, and suppresses the rise in the surface temperature of the artificial lawn by the heat of vaporization. By incorporating the palm filler into the packing layer 24, the temperature of the place where the artificial lawn is laid can be effectively lowered, especially in the summer when the temperature tends to rise, and the occurrence of heat stroke can be suppressed.
The coconut filler is mixed in a volume ratio of 5% or more with respect to the entire filling layer 24 in order to sufficiently obtain the above-mentioned temperature rise suppressing effect.

The filling layer 24 lowers the temperature when the temperature rises by containing a palm filler that retains the water that comes into contact with the filling layer 24 during drying, but especially in a stadium for performing sports such as ball games and athletics. In some cases, water is sprinkled on the artificial lawn laid to lower the temperature, or competitions are held in rainy weather. At this time, it is preferable that the feeling that the player steps on the artificial lawn and the way the ball bounces used in the ball game have a small change between the dry state and the wet state of the artificial lawn. In addition, in cases such as soccer where standards are set for artificial grass used in stadiums, the change in usability between the dry state and the wet state is reduced to deviate from the set standards. You can also expect the effect of making it difficult.

Hereinafter, examples and comparative examples of the artificial lawn 2 according to the present invention will be described.
The upper surface of the base cloth 22 in which the turf thread 21 is planted in a cut pile shape is filled with silica sand as hard grains to a thickness of 10 mm, and a palm filler is filled therein to a thickness of 8 mm, and a brush is applied from above. Press and mix these. Further, silica sand is filled to a thickness of 10 mm, a palm filler is filled to a thickness of 7 mm, and a brush is pressed again to mix the lower layer 24a, which is a mixture of hard grains and a palm filler, to 35 mm. Form to the thickness of.
The upper surface of the lower layer 24a is filled with elastic particles in which styrene resin-based elastomer is granularly formed as elastic particles to a thickness of 5 mm to form a surface layer 24b made of elastic particles, and the artificial lawn 2 of Example 1 is formed. Provided.
That is, the artificial turf 2 of Example 1 is provided with an elastic grain having a total thickness of 5 mm, a palm filling layer having a total thickness of 15 mm, and a hard grain having a total thickness of 20 mm in the filling layer 24. When the volume ratio of each packed grain in the packed layer 24 is calculated based on the size of the filled thickness, the artificial turf 2 of the first embodiment has 12.5% by volume of elastic grains and 37.5% by volume of elastic grains. The filling layer 24 is composed of the coconut filler and 50% by volume of hard grains.

In the first embodiment and the examples and comparative examples described later, in the formation of the lower layer 24a, the work of filling and mixing the hard grains and the coconut filler is repeated twice, but the work is carried out three times or more. It may be carried out repeatedly, or it may be carried out in one operation.

In Example 2, in the same procedure as in Example 1, a palm filler having a total thickness of 12 mm and silica sand having a total thickness of 20 mm are mixed to form a lower layer 23a, and a styrene resin having a thickness of 8 mm is formed. The surface layer 24b was formed from the system elastomer.
That is, in Example 2, the filling layer 24 is composed of 20% by volume of elastic grains, 30% by volume of coconut filler, and 50% by volume of hard grains.

In Example 3, the lower layer 23a was formed by mixing a palm filler having a total thickness of 10 mm and silica sand having a total thickness of 20 mm, and the surface layer 24b was formed from a styrene resin-based elastomer having a thickness of 10 mm.
That is, in Example 3, the filling layer 24 is composed of 25% by volume of elastic grains, 25% by volume of coconut filler, and 50% by volume of hard grains.

In Example 4, the lower layer 23a was formed by mixing a palm filler having a total thickness of 10 mm and silica sand having a total thickness of 18 mm, and the surface layer 24b was formed from a styrene resin-based elastomer having a thickness of 12 mm.
That is, in Example 4, the filling layer 24 is composed of 30% by volume of elastic grains, 25% by volume of coconut filler, and 45% by volume of hard grains.

In Example 5, the lower layer 23a was formed by mixing a palm filler having a total thickness of 15 mm and silica sand having a total thickness of 18 mm, and the surface layer 24b was formed from a styrene resin-based elastomer having a thickness of 12 mm.
That is, in Example 5, the filling layer 24 is composed of 26.7% by volume of elastic particles, 33.3% by volume of coconut filler, and 40% by volume of hard particles.

In Example 6, the lower layer 23a was formed by mixing a palm filler having a total thickness of 15 mm and silica sand having a total thickness of 15 mm, and the surface layer 24b was formed from a styrene resin-based elastomer having a thickness of 10 mm.
That is, in Example 6, the filling layer 24 is composed of 25% by volume of elastic particles, 37.5% by volume of coconut filler, and 37.5% by volume of hard particles.

In Example 7, the lower layer 23a was formed by mixing a palm filler having a total thickness of 15 mm and silica sand having a total thickness of 13 mm, and the surface layer 24b was formed from a styrene resin-based elastomer having a thickness of 12 mm.
That is, in Example 6, the filling layer 24 is composed of 30% by volume of elastic grains, 37.5% by volume of coconut filler, and 32.5% by volume of hard grains.

In Comparative Example 1, a coconut filler having a total thickness of 15 mm and silica sand having a total thickness of 25 mm were mixed in the same procedure as in Example 1 to form a packed layer 24 having a one-layer structure.
That is, in Comparative Example 1, the filling layer 24 is composed of 37.5% by volume of coconut filler and 62.5% by volume of hard grains.

In Comparative Example 2, a coconut filler having a total thickness of 20 mm and silica sand having a total thickness of 20 mm were mixed to form a packed layer 24 having a one-layer structure.
That is, in Comparative Example 2, the filling layer 24 is composed of 50% by volume of coconut filler and 50% by volume of hard grains.

In Comparative Example 3, a coconut filler having a total thickness of 25 mm and a silica sand having a total thickness of 15 mm were mixed to form a packed layer 24 having a one-layer structure.
That is, in Comparative Example 3, the filling layer 24 is composed of 62.5% by volume of coconut filler and 37.5% by volume of hard grains.

Hereinafter, a method for evaluating the change in usability between the dry state and the wet state of the packed layer 24 of the artificial lawn 2 will be described.
In sports competitions such as soccer, various standards are set for artificial grass used in the stadium, and the impact absorption rate used as one of the standards is used to evaluate the magnitude of the change. I made it.
In addition, the observation result of the state when the artificial lawn 2 in the wet state was stepped on with a foot was set as one of the evaluation items.

In the method of measuring the shock absorption rate, first, a weight of 20 kg is dropped from a height of 55 cm from the surface of the artificial lawn 2, and the maximum force A (N) applied to the surface when the weight collides is measured. To do. The above measurement is performed twice within 30 seconds at the same measurement location, and the value of A measured the second time is applied to the following formula to calculate the shock absorption rate F (%).

Shock absorption rate F (%) = 1- (A / 6760) x 100

A Clubtester DLTC0036 manufactured by Deltec was used for the above-mentioned measurement of the shock absorption rate.

With respect to the artificial lawns 2 of Examples 1 to 7 and Comparative Examples 1 to 3, the shock absorption rate was measured based on the above method, and the state of being stepped on by a foot was observed.
Specifically, first, a sample of artificial lawn 2 having a size of 50 cm in length and 50 cm in width was prepared indoors, and the impact absorption rate Fd (%) in a dry state was measured based on the above measurement method.

Next, water was poured from above the above sample using a watering can, and water was supplied at a rate of 4 liters / square meter.
After 10 minutes of pouring water, the surface of the wet sample was stepped on with a foot, and the generation of a squishy and unpleasant sound and the degree of touch were observed.
Further, the sample was stepped on with a foot, and the entire sample was stepped on a total of 250 times, and then the impact absorption rate Fw (%) in a wet state was measured at the place where the sample was stepped on by the above method.

The ratio (Fw / Fd) of the impact absorption rate Fd in the dry state and the impact absorption rate Fw in the wet state measured by the above method is calculated, and the magnitude of the fluctuation in usability between the dry state and the wet state is calculated based on the value. Was evaluated.
In addition, the observation results when the wet sample was stepped on with a foot were evaluated based on the presence or absence of unpleasant sounds or touches.
The results of these evaluations performed on Examples 1 to 7 and Comparative Examples 1 to 3 are as shown in the table of FIG.

As shown in the table of FIG. 2, the observation results when the wet sample was stepped on by foot were used for Comparative Examples 1 and 2 in which the coconut filler was contained in the packing layer 24 in an amount of 50% by volume or more. The feeling was bad, but good results were obtained for other samples containing less than 50% by volume.
This is because when the filling layer 24 containing the water-retaining palm filler is stepped on with a foot, air bubbles are generated around the palm filler due to the water and air squeezed from the palm filler, and the bubbles are further crushed to make a sound. However, it is considered that the above-mentioned sound and feel reach an unpleasant level as the amount of the coconut filler increases.
Therefore, the coconut filler contained in the packing layer 24 is preferably 45% by volume or less so as not to be 50% by volume or more.

As shown in the table of FIG. 2, in Comparative Example 1 in which the packed layer 24 contains hard particles in a proportion of more than 50% by volume, the ratio of the impact absorption rate in the dry state and the wet state is significantly less than 0.8. The result was 0.72, which means that the shock absorption rate fluctuates greatly between the dry state and the wet state, and the usability fluctuates greatly.
Further, in Comparative Example 2 in which the hard particles in the packed layer 24 were 50% by volume, the value of the ratio of the impact absorption rate in the dry state and the wet state was lower than 0.8, and the usability varied greatly. became.
On the other hand, in Examples 1 to 7 in which the hard particles were contained in the packed layer 24 at a ratio of 50% by volume or less and the elastic particles were contained, the ratio of the impact absorption rates in the dry state and the wet state was high. , A result exceeding 0.8 was obtained. In particular, in Examples 2 to 7 containing 20% by volume or more of elastic particles, the ratio of the shock absorption rate is 0.87 or more, which greatly exceeds 0.8, and the shock absorption rate fluctuates between the dry state and the wet state. Good results were obtained that the value was small and the fluctuation in usability was small.

The artificial lawn 2 according to the present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist of the present invention.
For example, the artificial lawn 2 of Examples 1 to 7 is provided with a filling layer 24 in a two-layer structure including a lower layer 24a in which hard grains and a coconut filler are mixed and a surface layer 24b formed of elastic grains. However, the present invention is not limited to this, and it may be provided in a single-layer structure in which all of these are mixed, or in a three-layer structure in which different layers are formed of hard grains, coconut filler, and elastic grains. .. Further, the volume ratio of each filler constituting the filler 24 may be provided in another layer structure satisfying the requirements of the invention.

In the artificial lawn 2 of Examples 1 to 7, the surface layer 24b constituting the uppermost surface of the filling layer 24 is formed only of elastic grains, and the lower layer 24a formed so as to be in contact with the elastic grains is contained with a coconut filler. There is.
By not including the palm filler in the surface layer 24b in this way, the contact of the palm filler with the athletes and competition equipment competing on the artificial lawn 2 is suppressed, and the palm filler adheres to these. It can be expected to have the effect of suppressing problems such as causing stains and excessive wetting of the palm filler with the water retained.
Further, by providing the surface layer 24b so as to cover the lower layer 24a containing the palm filler, the contact between the palm filler and the outside air is reduced, and the rapid vaporization of the water retained by the palm filler is suppressed. The effect of suppressing the temperature rise by the palm filler can be expected to be maintained for a long time.

1 Foundation layer 2 Artificial lawn 21 Turf thread 22 Base cloth 23 Backing layer 24 Filling layer

Claims (2)

An artificial lawn in which turf threads are planted on a base cloth, and a filler is filled between the planted turf threads to provide a filling layer.
The filler comprises hard granules, elastic granules and a coconut filler based on natural coconut.
The filling layer is composed of hard grains of 1% or more and 50% or less in volume ratio, coconut filler of 5% or more and 45% or less, and the balance of elastic grains .
The packed bed includes a surface layer and a lower layer arranged so as to be in contact with the bottom of the surface layer. The surface layer contains the elastic particles and the elastic particles are a synthetic resin elastomer, synthetic rubber, or natural rubber. It is made of elastic grains, which are either single or a combination of crushed rubber products.
The palm filler is contained in the lower layer, and the palm filler contained in the filling layer in a volume ratio of 5% or more and 45% or less is not contained in the surface layer, so that the palm filler is on the artificial lawn. An artificial lawn that is characterized by being difficult to contact with athletes. The artificial lawn according to claim 1, wherein the elastic particles are contained in an amount of 20% or more in a volume ratio.

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