JP2017179696A - Artificial lawn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recyclable artificial lawn.SOLUTION: An artificial lawn includes a base material having a front surface and a rear surface, a plurality of piles resembling a lawn leaf standing on the front surface of the base material, and a backing layer formed on the rear surface of the base material for preventing dropout of the pile from the base material. The base material, the pile and the backing layer are composed of a thermoplastic resin. Preferably, the backing layer is formed of a fused and foamed thermoplastic resin.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an artificial turf and a method for manufacturing the same.

  In recent years, artificial turf has become widespread in various athletic facilities such as a soccer field, a rugby field, and a baseball field. In many cases, such artificial turf has a backing layer for preventing the pile from falling off from the base material on the back side of the base material after planting a large number of piles imitating turf leaves on the base material. Manufactured by forming. Usually, the base material and the pile are made of a thermoplastic resin, but the backing layer is made of a thermosetting resin such as SBR latex or urethane (for example, see Patent Document 1).

JP 2009-144428 A

  The thermoplastic resin constituting the base material and the pile is a material that can be recycled because it can be melted and remolded. However, since this cannot be done for the thermosetting resin or the like constituting the backing layer, if the backing layer made of the thermosetting resin or the like is fixed to the base material and the pile, the whole can only be discarded by incineration or the like. Therefore, it is difficult to recycle such artificial turf after the end of its useful life.

  An object of the present invention is to provide a recyclable artificial turf and a method for manufacturing the same.

  The artificial turf according to the first aspect of the present invention has a base material having a front surface and a back surface, a large number of piles simulating turf leaves standing on the surface of the base material, and the pile falls off from the base material. A backing layer formed on the back surface of the substrate. The base material, the pile and the backing layer are made of a thermoplastic resin.

  The artificial turf according to the second aspect of the present invention is the artificial turf according to the first aspect, and the backing layer is a foam layer.

  The artificial turf according to the third aspect of the present invention is the artificial turf according to the first aspect or the second aspect, wherein the base material, the pile and the backing layer are made of the same material.

  The artificial turf according to a fourth aspect of the present invention is the artificial turf according to any one of the first to third aspects, wherein the backing layer is made of polyethylene.

The artificial turf manufacturing method according to the fifth aspect of the present invention includes the following steps.
(1) The step of preparing the intermediate body of the said artificial turf containing the base material which has a surface and a back surface, and many piles which imitated the turf leaf which stands on the said surface of the said base material.
(2) A step of forming a backing layer by applying a molten thermoplastic resin on the back surface of the base material included in the intermediate.

  The artificial turf manufacturing method according to the sixth aspect of the present invention is the artificial turf manufacturing method according to the fifth aspect, wherein, in the step (2), on the back surface of the base material included in the intermediate. Next, a molten and foamed thermoplastic resin is applied.

  According to the present invention, the base material, the pile and the backing layer included in the artificial turf are made of the thermoplastic resin. Therefore, these can be melted together and reshaped. Therefore, the artificial turf can be recycled.

The side view of the artificial turf concerning one embodiment of the present invention. The figure explaining the formation process of a backing layer.

  Hereinafter, an artificial turf and a manufacturing method thereof according to an embodiment of the present invention will be described with reference to the drawings.

<1. Artificial grass>
The artificial turf 1 according to the present embodiment is installed on an installation surface such as an asphalt surface or the ground in various sports competition facilities such as a soccer field, a rugby field, and a baseball field. As shown in FIG. 1, the artificial turf 1 has a base 2 and a large number of piles 3 simulating turf leaves standing on the surface 2 a of the base 2. The base material 2 is formed in a sheet shape, and the pile 3 is planted on the base material 2 at a predetermined interval. Further, a backing layer 4 for preventing the pile 3 from falling off the base material 2 is formed on the back surface 2 b of the base material 2.

  The base material 2 is comprised from a thermoplastic resin, and is comprised from polyethylene in this embodiment. The base material 2 can be formed as a plain woven fabric made of the above materials, for example.

  The pile 3 is also comprised from a thermoplastic resin, and is comprised from polyethylene similarly to the base material 2 in this embodiment. The pile 3 can be formed using, for example, a flat filament yarn (yarn) made of the above materials. The pile 3 of the present embodiment is fixed to the base material 2 by sewing the yarn to be the pile 3 into the base material 2 using a tufting machine. Although the length W1 (average value) from the surface 2a of the base material 2 to the tip of the pile 3 is not particularly limited, it can be relatively short as 20 mm ≦ W1 (average value) <50 mm (generally a short pile) 50 mm ≦ W1 (average value) ≦ 70 mm (which is generally called a long pile). The cross-sectional shape of the pile 3 can be various shapes such as a triangle, a quadrangle, an ellipse, and a star.

  The backing layer 4 is also made of a thermoplastic resin. In the present embodiment, the backing layer 4 is made of polyethylene like the base material 2 and the pile 3. Moreover, the backing layer 4 of this embodiment is a foam layer, and is formed from melted polyethylene containing a foaming agent.

  As described above, the base material 2, the pile 3 and the backing layer 4 of the present embodiment are all made of a thermoplastic resin. Therefore, although these members 2 to 4 are fixed to each other, they can be melted together and re-molded, so that they can be recycled after their useful life has passed. In this embodiment, since these members 2 to 4 are all made of the same material (polyethylene), they can be reused in a wide range of applications during recycling. Moreover, the adhesiveness with respect to the base material 2 and the pile 3 of the backing layer 4 also becomes favorable, and the function of preventing the pile 3 from falling off from the base material 2 is exhibited well.

  Note that each of the backing layer 4, the base material 2, and the pile 3 does not necessarily need to be composed of only a thermoplastic resin, and may include a material other than the thermoplastic resin. In the present embodiment, when specific parts such as the backing layer 4, the base material 2, and the pile 3 are said to be “consisting of (specific material)”, it means that most of the part is composed of the material. Quantitatively, the weight percentage W of the material at the site is 50% or more. However, from the viewpoint of improving recyclability, the weight percentage W of the thermoplastic resin of the backing layer 4 is preferably 60% or more, more preferably 70% or more, and further preferably 80% or more. Preferably, it is 90% or more, more preferably 95% or more, still more preferably 96% or more, still more preferably 97% or more, and further preferably 98% or more. Preferably, it is 99% or more. Of course, if W = 100%, the recyclability is extremely excellent. The same applies to the base material 2 and the pile 3.

  A filler 5 is filled between the piles 3 on the surface 2 a of the substrate 2. The filler 5 serves as a cushioning material for preventing the player from being injured during play, and can also protect the grass. In addition, the filler 5 can adjust the degree of ball movement used in the competition and can control the runnability of the players, and can improve the performance of the competition on the artificial turf 1. it can. In addition, although such a filler 5 can also be abbreviate | omitted, when the pile 3 is a pile with comparatively high height called a long pile, it is used especially preferable.

  As the filler 5, at least one of an elastic filler 5a and a hard filler 5b can be used. As the elastic filler, for example, rubber chips made of crushed waste tires or the like can be used. As the hard filler, for example, sand can be used. In the example of FIG. 1, both the hard filler 5 b and the elastic filler 5 a are filled between the piles 3.

  As described above, the filler 5 does not need to be made of a thermoplastic resin like the base material 2, the pile 3 and the backing layer 4. Since the filler 5 is not fixed to the base material 2, the pile 3 and the backing layer 4, it can be easily separated from these members 2 to 4. Therefore, even if the filler 5 is made of a material other than the thermoplastic resin, only the base material 2, the pile 3 and the backing layer 4 can be recovered and recycled.

<2. Manufacturing method>
Next, an example of a method for manufacturing the artificial turf 1 will be described. First, as a material for forming the pile 3 (hereinafter referred to as a pile material), a thermoplastic resin (polyethylene in this embodiment) mixed with a green colorant is prepared. Next, the pile material is put into an extruder and melt extrusion molding is performed under a predetermined temperature condition. Thereby, a thread-like pile material is extruded from the opening of the extruder. The temperature condition at this time can be a temperature higher than the melting point of the pile material, for example, 240 ° C. Subsequently, the thread-like pile material extruded from the extruder is cooled and solidified in a water tank, and the thread is uniaxially stretched. As a method for uniaxial stretching, a roll stretching method can be used. Thereafter, a relaxation heat treatment is performed in the hot water tank to produce a yarn made of a pile material. After the relaxation heat treatment, the yarn is wound up into a yarn roll.

  After the production of the yarn rolls, the yarns fed from these yarn rolls are planted on the substrate 2 using a tufting machine. In the present embodiment, a plurality of yarn rolls are prepared, and after twisting a plurality of yarns fed out from each of the yarns, the twisted yarns are subjected to a base material 2 (in this embodiment, Sew to polyethylene). As a result, a plurality of piles 3 stand up from the same location on the substrate 2. Hereinafter, the member formed of the base material 2 and the pile 3 formed so far is referred to as an intermediate body (indicated by reference numeral 8 in FIG. 2). However, in FIG. 2, the pile 3 is omitted for simplicity.

Subsequently, the backing layer 4 is formed on the back surface 2 b of the base material 2 included in the intermediate body 8 in order to firmly fix the pile 3 to the base material 2. In the present embodiment, the backing layer 4 is made of a material in which a foaming agent is mixed with polyethylene (hereinafter referred to as a backing agent). For example, the backing agent represents Novatec (registered trademark) LL (UF240) manufactured by Japan Polyethylene Co., Ltd., and Polyslene EE206 manufactured by Eiwa Kasei Kogyo Co., Ltd. as a foaming agent is 5 phr (phr = weight of resin with respect to 100 weight of resin). The material can be mixed at a ratio of (unit). Specifically, in this embodiment, as shown in FIG. 2, a backing agent is charged into an extruder 10 to which a T die 11 is attached, and melt extrusion molding is performed under a predetermined temperature condition. Thereby, the sheet-like backing agent 4a is pushed out from the linear opening of the T die 11. The thickness of the linear opening of the T die 11 can be set to about 1 mm, for example. Further, the temperature condition at this time can be set to a temperature higher than the melting point of the backing agent, for example, 240 ° C. On the other hand, the extruded sheet-like backing agent 4 a is received on the intermediate body 8 that is conveyed below the linear opening of the T die 11. At this time, the intermediate body 8 has the back surface 2b side of the base material 2 facing the sheet-like backing agent 4a. As a result, the molten backing agent 4 a is applied onto the back surface 2 b of the base material 2 of the intermediate body 8. The coating amount of the backing layer 4 can be, for example, about 1000 g / m ² on the back surface 2b of the substrate 2. Then, in the process in which the intermediate 8 coated with the backing agent 4a is further conveyed, cool air is sent toward the backing agent 4a. Thereby, the backing agent 4a is cooled and solidified on the intermediate body 8, and the backing layer 4 fixed on the back surface 2b of the base material 2 is formed.

  At the time of extrusion molding for forming the backing layer 4, the backing agent 4a is melted by being heated. Therefore, the backing agent 4a immediately after being discharged from the T die 11 is still kept at a high temperature. However, in this embodiment, the backing agent 4a at this time is foamed by the foaming agent contained in the backing agent 4a. Therefore, in the above coating process of the backing agent 4a, heat is not excessively transferred from the backing agent 4a to the intermediate body 8, and the situation where the intermediate body 8 made of the thermoplastic resin is melted is prevented. Can do. As a result, the appearance of the artificial turf 1 that is finally produced is maintained beautifully.

<3. Modification>
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible unless it deviates from the meaning. For example, the following changes can be made. Moreover, the gist of the following modifications can be combined as appropriate.

<3-1>
In the said embodiment, although the base material 2, the pile 3, and the backing layer 4 were all made from polyethylene, it can also be comprised from another thermoplastic resin, for example, a polypropylene. Further, the base material 2, the pile 3 and the backing layer 4 do not have to be made of the same resin material. For example, the base material 2 is made of polypropylene, and the pile 3 and the backing layer 4 are made of polyethylene. It can also be.

<3-2>
The backing layer 4 may not be a foamed layer, but as described above, when the foamed layer is used, the intermediate 8 can be prevented from melting in the step of applying the backing agent 4a. In addition, the intermediate body 8 can be prevented from melting in the coating step of the backing agent 4a by a method other than the method of using the backing layer 4 as the foam layer. For example, a thermoplastic resin having a melting point T1 lower than the melting point T2 of at least one of the base material 2 and the pile 3 is selected as the material constituting the backing layer 4. If the backing agent 4a is melted at a temperature that is equal to or higher than T1 and lower than T2 in the coating step of the backing agent 4a, the melting of the intermediate body 8 can be prevented as in the above embodiment.

  In addition, in the coating process of the backing agent 4a, the entire temperature of the base material 2 and the pile 3 is not necessarily increased to the same temperature as the backing agent 4a due to heat transfer from the backing agent 4a. Therefore, if T1 is the same as T2 or slightly higher (several degrees Celsius), it is possible to prevent the base material 2 and the pile 3 from melting, and similarly, the appearance of the artificial turf 1 can be maintained beautifully. However, it is preferable that T1 ≦ T2. In addition, polyethylene is used for a wide variety of uses among thermoplastic resins, and since it is a material having a relatively low melting point, it is preferable to use polyethylene as the backing layer 4. When the base material 2, the pile 3 and the backing layer 4 are all made of polyethylene, there are various uses for recycling.

DESCRIPTION OF SYMBOLS 1 Artificial turf 2 Base material 2a Front surface 2b Back surface 3 Pile 4 Backing layer 4a Backing agent 8 Intermediate body W1 Turf height

Claims (6)

A substrate having a front surface and a back surface;
A number of piles imitating turf leaves standing on the surface of the substrate;
A backing layer formed on the back surface of the substrate to prevent the pile from falling off the substrate;
With
The substrate, the pile and the backing layer are composed of a thermoplastic resin.
Artificial grass. The backing layer is a foam layer;
The artificial turf according to claim 1. The base material, the pile and the backing layer are composed of the same material,
The artificial turf according to claim 1 or 2. The backing layer is composed of polyethylene,
The artificial turf according to any one of claims 1 to 3. A method for manufacturing artificial turf,
Providing an intermediate of the artificial turf comprising a substrate having a front surface and a back surface, and a number of piles imitating turf leaves standing on the surface of the substrate;
Forming a backing layer by applying a molten thermoplastic resin on the back surface of the base material included in the intermediate body. In the step of forming the backing layer, a molten and foamed thermoplastic resin is applied on the back surface of the base material included in the intermediate.
The manufacturing method of the artificial turf of Claim 5.