JP2000290917A - Artificial lawn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure recycling performance, and to inexpensively secure adhesive strength of a joint part of an artificial lawn by mixing organic and inorganic granular bodies easily adhesive to a backing side adhesive layer in a joining part with the backing side adhesive layer of a backing layer. SOLUTION: Artificial lawn grass threads 2 are fixed to the reverse side of a base material 3 by a backing layer 4, and even after adhering/fixing the artificial lawn grass threads 2, a thermoplastic adhesive material 4a is used as the backing layer 4. In this case, polyethylene and polypropylene are used as the adhesive material 4a. When sticking a joint tape 5 to the backing layer 4, the backing layer 4 and the joint tape 5 are firmly joined, so that granular bodies 6 play a role of an anchor to an adhesive layer 5b. Thus, the adhesive material 4a is mixed with the granular bodies 6 as a powder shape, and is sprayed to obtain the backing layer 4 by uniformly dispersing the granular bodies 6. Thus, recycling performance is secured, and adhesive strength of a joint part between an artificial lawn is inexpensively enhanced to prevent the occurrence of a separation phenomenon in a joint part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an artificial turf for use in a sports facility or the like, and more particularly, to an artificial turf that enables recycling (recycling and effective use of waste).

[0002]

2. Description of the Related Art For example, to construct a large surface such as a tennis court on artificial grass, as shown in FIG.
A plurality of artificial turf 1a is laid on the ground G, and adjacent ends thereof are connected via a joint tape 5.

[0003] Artificial lawn 1 used in this kind of competition facility
a, a large number of artificial turf yarns (pile) 2 are planted on a base material (base cloth) 3, and the artificial turf yarn 2 is formed on the back surface side of the base material 3 by a backing layer 4 made of an adhesive. It is fixed to 3.
The backing layer 4 also has a role of reinforcing the base material 3.

As the joint tape 5, a tape having an adhesive layer 5b on a tough band-like joint base 5a is used. To give a feeling closer to natural grass,
In order to fix the artificial grass 1a on the ground G, the grass is often filled with sand S.

[0005] Artificial turf can be used almost maintenance-free for a long time, but is not permanent. As the damage progresses, it will be replaced. However, in recent years where the treatment of industrial waste has become a social problem, the recyclability of artificial turf is also being sought.

Therefore, the applicant of the present invention, for example, in Japanese Patent Application No. 10-255106, does not lose the thermoplasticity even after bonding and fixing, as the backing layer 4, in place of the latex rubber used so far. Proposals have been made to provide artificial grass with recyclability by using a resin (polymer).

[0007]

According to this, since the entire artificial turf is unified with a resin having thermoplasticity, it is possible to apply, for example, a composite recycling method which is one of plastic material recycling methods. After that, the following new issues arose.

In other words, when a polymer having thermoplasticity is used even after being adhered and fixed to the backing layer 4, the adhesive strength at the joint part particularly by the joint tape 5 is not sufficient, and the pressure may be reduced due to the stepping pressure of the competitor. As shown in FIG. 9, it was found that the joint portion was peeled off and a so-called “puncture phenomenon” was easily caused.

The reason is presumed to be mainly due to the following points. First, many polymer materials having thermoplasticity even after adhesion and fixing are difficult to adhere to in the first place. In particular, those having a low melting point and being easy to handle have a strong tendency.

In addition, when a resin powder is melted and formed into a layer, generally with or without thermoplasticity, the surface becomes a smooth surface having a relatively small surface area, so that it is difficult to adhere to other materials. . Due to these causes, the backing layer 4
It is considered that a sufficient bonding force between the adhesive tape 5 and the adhesive layer 5b of the joint tape 5 cannot be obtained, and a “puncture phenomenon” occurs.

[0011]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve such a problem, and an object of the present invention is to provide a joint between artificial grasses at a low cost without impairing recyclability. An object of the present invention is to provide an artificial lawn capable of increasing the bonding strength.

According to the present invention, an object of the present invention is to provide an artificial turf comprising a substrate on which artificial turf is implanted, wherein the artificial turf has a thermoplastic property even after being adhered and fixed on at least the back side of the substrate. An artificial turf that is bonded and fixed by a backing layer made of a material, a plurality of which are laid on a ground, and adjacent ends are connected to each other via an adhesive layer arranged on the ground, This is achieved by mixing organic and / or inorganic particles having an easy-to-adhere property to the base-side adhesive layer into at least a portion of the layer to be joined to the base-side adhesive layer.

In other words, the backing layer is made of an adhesive having thermoplasticity even after bonding and fixing. According to the present invention, individual particles that are easily adhered are mixed in the backing layer so as to be wrapped in the adhesive. Therefore, the strength of the backing layer itself is increased. In addition, since the particles exposed on the surface of the backing layer penetrate into the underlying adhesive layer or, depending on the material of the particles, strongly adhere to the underlying adhesive layer, the bonding strength between the backing layer and the underlying adhesive layer ( Adhesion) is also increased.

[0014] The joint between the ends of the artificial turf is usually made of a joint tape having an adhesive layer on the surface. The ends of the artificial grass may be joined via an adhesive layer. In the present invention, any of the embodiments is included in the base-side adhesive layer.

In the present invention, the particles mixed into the backing layer preferably have easy adhesion to the adhesive forming the backing layer. (Affinity, adhesion) may be based on the material itself, or may be made to impart easy-adhesion to the granules by its shape effect. In any case, since the granules have an easy-to-adhere property, the adhesive strength can be increased with a small amount of the granules, and the thermoplasticity of the adhesive is maintained, so that the recyclability is not impaired.

In particular, when the ease of adhesion to the backing layer and / or the underlying adhesive layer is determined by the shape effect, it can be said that the polishing powder generated by the polishing operation is optimal. That is, since the abrasive powder has a remarkably large surface area as compared with a powder having the same weight, the abrasive powder is extremely excellent in easy adhesion to the adhesive, and the amount of the abrasive powder to the adhesive can be relatively reduced. Moreover, this type of abrasive powder has no particular use and is discarded as it is, so that it can be obtained at low cost.

The adhesive having thermoplasticity even after the adhesive layer for forming the backing layer is olefinic thermoplastic resin, typically polypropylene or polyethylene. Among them, isotactic polymer and atactic polymer are preferred. , And ethylene-containing copolymers.

Examples of the easily adhering particles familiar to the adhesive and the underlying adhesive layer include various rubbers, various urethanes,
Various thermoplastic elastomers can be exemplified,
In particular, urethane, natural rubber, styrene butadiene rubber and the like have high versatility and are preferably used.

Further, a thermoplastic resin may be used. For example, polyethylene may be used as the adhesive, and polypropylene having a high melting point may be used as easy-adhesive particles, and both may be heated to form a backing layer. As the inorganic granules, soil such as clay, sand and the like can be used in addition to calcium carbonate and aluminum oxide.

From the viewpoint of the adhesion between the adhesive having thermoplasticity and the particles even after bonding, the particles have a small particle size (for example, 1 mm or less) and a large surface area (for example, abrasive powder). Or the like with a scratched surface).

Thus, the particle size of the granules is preferably 1 m
However, if priority is given to the adhesiveness with the underlying adhesive layer, it is preferable that the particle size of the granules is larger.
For example, it is preferably 1 μm or more, more preferably 80 μm or more, and furthermore, 40 mesh / 300 μm.
If it is above, a sufficient adhesive effect is recognized. Also in this case, it is preferable that the surface shape is large as described above.

On the other hand, from the viewpoint of recyclability, it is preferable that the particle size of the granules is smaller (100 μm or less). In particular, it is 20 μm or less, more preferably 5 μm.
m or less.

That is, if the particle size of the particle is large, the particle remains as a foreign substance in the adhesive, so that the thermoplasticity of the adhesive may be impaired. On the other hand, when the particle size of the granules is small, the granules are dispersed as a so-called filler (aggregate) in the adhesive, so that the adhesive remains thermoplastic.

Generally speaking, in order to increase the adhesive strength, it is preferable that the particle size of the particles is 1 μm or more and 1 mm or less, and that the range of 1 to 100 μm is preferable in terms of recyclability. Table 1 shows these relationships for reference.

[Table 1]

From the viewpoint of recyclability, the mixing ratio of the adhesive and the granules is expressed by weight: adhesive: granules = 99: 1 to 1
It is preferably within the range of 20:80.

In the present invention, a backing layer containing particles is provided on the back surface of the base material. To obtain this backing layer, the raw material of the adhesive is powdered, and the granules are mixed with the powdered material. It is preferable to spray and heat and fuse the particles on the back surface, whereby a backing layer in which the particles are uniformly dispersed can be easily obtained.

However, either the powder or the granular material of the adhesive is sprayed on the back surface of the substrate first, and then the other is sprayed, and the adhesive is heated and fused to the substrate. It may be.

Separately from this, even after bonding and fixing as an adhesive, a polymer having thermoplasticity is melted in advance, granules are mixed therein, and then applied to the back side of the base material. You may.

When it is desired to obtain a higher grade of quality in terms of recycling, particles that are easily adhered are mixed only in the joint with the adhesive layer on the base side, and the old artificial grass is recovered. At the time of recycling, it is preferable to separate the joints at the ends where the particles are mixed and to recycle them by grade.

[0030]

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to an embodiment shown in the drawings. In this embodiment, the same reference numerals are given to portions which are the same as or are considered to be the same as those in the conventional example of FIG. 8 described above.

FIG. 1 is a cross-sectional view of a main part of a joint of an artificial lawn according to an embodiment of the present invention. According to this, this artificial lawn 1 also includes a base material 3 on which a large number of artificial grass yarns 2 are planted.

The artificial turf yarn 2 is preferably an olefin-based resin fiber, especially a polypropylene fiber, but other resin fibers may be used. Similarly, the base fabric 3 is also preferably a plain woven fabric of olefin resin fibers, particularly polypropylene fibers, but other resin fibers may be used. Further, it may be a non-woven fabric.

The artificial turf yarn 2 is fixed by a backing layer 4 on the back side of the substrate 3. According to the present invention, an adhesive (polymer) 4a having thermoplasticity is used for the backing layer 4 even after the artificial turf yarn 2 is adhered and fixed. As the adhesive 4a that satisfies such conditions, polypropylene and polyethylene are preferable, and among them, isotactic polymers, atactic polymers, and ethylene-containing copolymers are more preferable.

The artificial turf 1 is laid on the ground G, and its adjacent ends are connected to each other via the joint tape 5 on the backing layer 4 side. Also in this embodiment, after the connection with the joint tape 5, the sand of the artificial grass 1 is filled with the sand S.

In this embodiment, the particles 6 are mixed in at least the portion of the backing layer 4 where the joint tape 5 is to be applied. The material of the granules 6 may be either organic or inorganic, as long as the granules 6 have an easy-to-adhere property (affinity) to the adhesive layer 5b of the joint tape 5. It is more preferable that the granules 6 have easy adhesion to the adhesive 4 a forming the backing layer 4.

If the material is required to easily adhere to the backing layer 4 of the granular material 6 and the adhesive layer 5b of the joint tape 5, various organic rubbers, urethanes, thermoplastic elastomers and the like are exemplified. But especially urethane,
Natural rubber and styrene butadiene rubber are preferred. Examples of the inorganic particles include calcium carbonate, aluminum oxide, soil such as clay, and sand.

If the shape of the particles 6 is required to easily adhere to the backing layer 4 and the joint tape 5 to the adhesive layer 5b, the contact area between the granular material 6 and the adhesive material is large, and so-called "galling" is good. Are preferred. For example, polishing powder generated by the polishing process is optimal.

The particle diameter r of the granules 6 is 1 in view of increasing the strength of the adhesive 4 itself.
mm or less. More preferably, the surface area should be large like abrasive powder.

The particles 6 are uniformly mixed in the backing layer 4 so that some of the particles 6 are mixed as shown in FIG.
Is also exposed on the surface of the adhesive 4a, and as a result, the adhesive strength with the joint tape 5 is increased.

That is, when the joint tape 5 is bonded to the backing layer 4, the granules 6 bite into the adhesive layer 5 b of the joint tape 5 and serve as a so-called anchor. Strongly joined.

From the viewpoint of exhibiting the anchor effect of the granules 6 more, when the particle size r of the granules 6 is 1 mm or less, the larger the particle size r is, the better.
It is good to be above. For example, 40 mesh / 300 μm
With the above, sufficient bonding strength with the joint tape 5 can be obtained.

On the other hand, in order to maintain the recyclability of the adhesive 4, it is preferable that the particle diameter r of the granular material 6 is small.
Specifically, the thickness is 100 μm or less, preferably 20 μm or less, and more preferably 5 μm or less.

In summary, in order to increase the bonding strength, it is preferable that the particle size r of the granular material 6 is 1 μm ≦ r ≦ 1 mm.
This means that the particle diameter r is preferably in the range of 1 μm ≦ r ≦ 100 μm.

In the above embodiment, the granules 6 are mixed only in the portion of the backing layer 4 where the joint tape 5 is to be applied. However, considering the case where the artificial turf 1 is cut to an arbitrary width and used. , As shown in FIG.
In a preferred embodiment, the granules 6 are mixed over the entire part of the powder.

Also, as shown in FIG. 4, a line turf 7 for competition is inserted between the artificial turf 1, 1 and the artificial turf 1, 1 and the line turf 7 are connected to a joint tape 5 on the back side thereof. The present invention can also be applied to the case where the connection is made through the connection.

That is, by mixing the particles 6 into the backing layer 4 of the line turf 7 in the same manner as in the above embodiment, the peeling phenomenon (puncture phenomenon) of the line turf 7 can be prevented.

The artificial turf 1 can be obtained as follows. First, the first manufacturing example will be described with reference to FIG. The substrate 3 on which the artificial turf yarn 2 is implanted is transported in the direction of arrow A (rightward in FIG. 5) along the transport path by the transport rollers R, R with the back side thereof facing upward. A hopper 8 is provided on this transport path. Further, a heater 9 composed of, for example, an infrared heater is provided downstream of the hopper 8 in the transport direction.

In the first manufacturing example, the adhesive (polymer having thermoplasticity even after bonding) 4a forming the backing layer 4 is in the form of powder, and the organic or inorganic particles 6a
And a suitable amount is sprayed from the hopper 8 on the back side thereof as the substrate 3 is conveyed. Then, by being heated by the heater 9,
The backing layer 4 containing the particles 6 is formed on the back side of the substrate 3.

As described above, the adhesive 4a is preliminarily powdered and mixed with the granules 6 and sprayed.
Is uniformly dispersed, thereby obtaining a backing layer 4. Alternatively, two hoppers may be prepared, and the powder of the adhesive 4a may be sprayed from one of the hoppers, and the granules 6 may be sprayed from the other hopper. In this case, plasticity may be imparted to the powder of the adhesive 4a by a heater before the powder is sprayed.

As shown in the second manufacturing example of FIG. 6, a heating hopper (furnace) 9 having a heater 91 is used in place of the hopper 8, and the adhesive 4a is formed in the heating hopper 9. Can be melted and mixed with the granules 6, and the mixed melt can be applied to the back surface side of the substrate 3 to form the backing layer 4 including the granules 6.

[0051]

EXAMPLE Next, an example according to the present invention and a comparative example thereof, which were specifically performed in order to evaluate the joint state of the joint portion, workability (including cost) during manufacture, and recyclability, will be described. I do.

In each of the examples, artificial grass yarn was made of a pile made of polypropylene, which is a thermoplastic resin, and the base material was made of a plain woven cloth made of polypropylene, which is also a thermoplastic resin. As illustrated in FIG. 7, the joint tape 5 has an adhesive layer 5 on the surface of the synthetic resin sheet 5a.
As b, 200 g of a urethane adhesive (trade name: Omniglue UA) manufactured by Sumitomo Rubber Industries, Ltd. was applied per 1 m in length and 150 mm in width.

The evaluation of the adhesive strength was performed by attaching each end of the artificial turf 1, 1 to the adhesive layer 5b of the joint tape 5,
After curing for one week at room temperature, each end of the artificial turf 1, 1 is pulled at 100 mm per minute to apply a shearing force between the artificial turf 1 and the joint tape 5 to remove the peeled state. Observed.

For evaluation of the recyclability (presence or absence of thermoplasticity), the entire artificial turf was pulverized by a pulverizer to a particle size of about 5 mm, placed in an oven at 180 ° C., and the molten state was observed. Workability and its cost are those at the time of manufacture.

<< Example 1 >> Both had an average particle size of about 300 μm.
m polyethylene powder and urethane abrasive powder are mixed at a weight ratio of 100: 20, and 1 square m
300 g per unit and heated and melted to form a backing layer. The above joint tape was stuck on the backing layer of this artificial grass, and after curing for one week at room temperature, 100 mm / min.
When the adhesive strength was measured by applying a shear force of
f and therefore puncture (peeling) at the joint
No phenomena occurred. The workability and the production cost during the production were both very good, and the plasticity (recyclability) was also good.

<< Example 2 >> Both had an average particle size of about 200 μm.
m of powdered polyethylene and powdered clay in a weight ratio of 10
The mixture was mixed at a ratio of 0:20, sprayed at 300 g per square meter on the back surface side of the base material, and heated and melted to form a backing layer.
When the adhesive strength between the backing layer of this artificial turf and the joint tape was measured in the same manner as in Example 1, 30
No puncture phenomenon was observed at the joint portion at kgf. The workability and production cost during production were very good as in Example 1, and the plasticity was also good.

Example 3 Polyethylene was melted in a heating hopper, and urethane polishing powder having an average particle size of about 300 μm was mixed in a weight ratio of 100: 20, and the melt was applied to the back surface of the substrate. On the side, 300 g per square meter was applied to form a backing layer. When the adhesive strength between the backing layer of the artificial turf and the joint tape was measured in the same manner as in Example 1, the puncture phenomenon was not observed at the joint at 40 kgf as in Example 1. In addition, the workability and cost during production were not evaluated very good due to the fact that urethane polishing powder was put into the molten polyethylene or the application was troublesome. The plasticity was good.

Example 4 Powdered polyethylene having an average particle diameter of about 300 μm and rubber powder having an average particle diameter of about 20 μm were mixed at a weight ratio of 100: 20, and one square was placed on the back side of the substrate. 300 g per m was sprayed and melted by heating to form a backing layer. When the adhesive strength between the backing layer of the artificial turf and the joint tape was measured in the same manner as in Example 1, the puncture phenomenon was not observed at the joint at 35 kgf. Further, the workability and the production cost during the production were both very good, and the recyclability was also very good.

Comparative Example 1 A backing layer was formed by applying 300 g per square meter of only the molten polyethylene on the back side of the substrate. When the adhesive strength between the backing layer of the artificial turf and the above-mentioned joint tape was measured in the same manner as in Example 1, it was only 15 kgf, and a puncture phenomenon partially occurred at the joint. Both workability and cost during production were good. The plasticity was extremely good and the recyclability was rated highest.

<Comparative Example 2> As a bonding material, a backing layer was formed by applying 300 g per square meter of SBR / NR latex, which is a current standard product, to the back side of the substrate. The adhesive strength between the backing layer of this artificial turf and the joint tape was measured in the same manner as in Example 1.
And no puncture phenomenon was observed at the joint.
However, workability and cost at the time of manufacturing are normal, and cannot be said to be better than those of the above-described Examples 1 to 3. Regarding plasticity, recyclability could not be expected because the backing layer lost thermoplasticity after formation.

From the above results, according to the present invention, a high adhesive strength equivalent to that of the current product of Comparative Example 2 was obtained, so that no puncture phenomenon was observed at the joint portion, and the stable edge between the artificial grass ends was obtained. It was confirmed that a joined state was obtained.

Further, workability and cost during manufacturing are improved, and recyclability is not lost. For reference, Table 2 shows the comparison results of Examples 1 to 3 and Comparative Examples 1 and 2. In this table, ◎ indicates extremely good, ○ indicates good, Δ indicates normal, and × indicates poor.

[Table 2]

[0063]

As described above, according to the present invention,
When a polymer having thermoplasticity is used as the adhesive for the backing layer for fixing the artificial turf yarn implanted in the base material even after bonding and fixing, an easily adhering organic and / or By incorporating the inorganic particles, the adhesive strength of the joint between the artificial grasses can be increased at a low cost without impairing the recyclability. Therefore, an artificial lawn having stable properties without a risk of occurrence of a peeling phenomenon at the joint portion can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part showing a laid state of an artificial lawn according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a joint part in FIG.

FIG. 3 is a cross-sectional view of a principal part similar to FIG. 1, showing a modified embodiment of the present invention.

FIG. 4 is a cross-sectional view of a principal part similar to FIG. 1, showing a modified embodiment of the present invention.

FIG. 5 is a schematic view showing a first production example for obtaining an artificial lawn according to the present invention.

FIG. 6 is a schematic view showing a second production example for obtaining an artificial lawn according to the present invention.

FIG. 7 is an explanatory diagram for explaining an adhesive strength test performed in a specific example of the present invention and a comparative example thereof.

FIG. 8 is a cross-sectional view of a main part showing a laid state of a conventional artificial lawn.

FIG. 9 is a schematic view showing a state in which the artificial grass is peeled off in the conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 artificial grass 2 artificial grass yarn 3 base material 4 backing layer 4 a adhesive 5 joint tape 5 a joint base 5 b adhesive layer 6 granules 7 line grass 8 hopper 9 heating hopper G underground R transport roller S mesh sand

Claims (6)

[Claims] An artificial grass yarn is provided on a substrate, and the artificial grass yarn is bonded and fixed on at least a back side of the substrate by a backing layer made of a thermoplastic adhesive even after bonding and fixing. In the artificial lawn, a plurality of the artificial grasses are laid on a ground, and adjacent ends are connected via an adhesive layer arranged on the ground side, at least the ground-side adhesive layer of the backing layer An organic lawn characterized in that organic and / or inorganic particles having an easy-to-adhere property to the base-side adhesive layer are mixed in a portion to be joined to the base. 2. The artificial turf according to claim 1, wherein the particles have an easy-to-adhere property to the adhesive of the backing layer. 3. The artificial turf according to claim 1, wherein the easy-adhesion of the granules depends on the material itself. 4. The artificial turf according to claim 1, wherein the ease of attachment of the granules depends on the surface shape. 5. The artificial grass according to claim 1, wherein the granules are polishing powder generated in a polishing step. 6. The backing layer is characterized in that the backing layer is formed by dispersing the adhesive in the form of powder containing the granules on the back surface of the base material and heat-sealing the base material to the base material. The artificial lawn according to any one of claims 1 to 5.