TW202021767A - Non-uniform artificial turf infill - Google Patents

Abstract

An artificial turf simulating grass including a layer of dispersed non-uniform, polyvinyl chloride-based particulates having non-symmetrical shapes and different sizes.

Description

Non-uniform artificial turf filler

This application claims US Provisional Application No. 62/742,539 (filed on October 8, 2018), which is incorporated herein by reference.

The present invention relates to artificial turf, in particular to turf fillers composed of polymer particles, granules or pellets. Artificial turf is generally used on sports and track and field surfaces, but can also be used in other applications to imitate lawn and grass surfaces, such as sports turf, synthetic lawn, landscape, private facilities, parks, commercial surfaces, municipal venues, test venues, etc. .

Artificial turf usually includes synthetic fibers or filamentous fibers, which are bundled into a textile material with an adhesive backing that can fix the fibers or filamentous fibers so that the blades of the grass can be simulated as upright Artificial turf layer. Natural and/or synthetic granular materials such as granulated and pelletized materials, including, for example, one or more rubber, vinyl, sand and various polymers, are generally dispersed in an upright synthetic turf layer as a filler, usually called For turf filler. The type of filler provides artificial turf performance characteristics, such as shock absorption, ball rebound, friction, ball rolling, weather resistance, and other characteristics specific to the structure of a specific synthetic turf.

The conventional synthetic filler materials are generally uniform in shape and size, for example, synthetic fillers such as rubber, polymers, and similar materials having the same spherical and cylindrical shapes and sizes. U.S. Patent Publication No. US 2017/0233956 (Publication of '956) (which is incorporated herein by reference in its entirety) describes that filler pellets composed of polyvinyl chloride (PVC) can be extruded and cut to provide Many different shapes (such as stars, polygons, hearts and triangles) to improve interlocking traction and performance characteristics of artificial turf. Like other conventional filling materials, the '956 application only considers the uniform and regular shape and size of the filling.

The embodiments of the present invention provide an improvement over conventional fillers with regular shapes and generally uniform sizes for filler particulate materials. The invention provides a non-uniform filling pellet, granule or granular material composed of PVC in artificial and synthetic turf equipment.

In the embodiments of the present invention, the PVC filler pellets and granules dispersed in the artificial turf equipment as fillers have various sizes and irregular shapes, such as asymmetric shapes, to give the artificial turf improved performance characteristics. In a specific embodiment, these shapes include seed-like shapes and droplet-like shapes of different sizes. In further embodiments, such shapes generally include oval, oval, and oblong. In a further embodiment, such shapes generally include biconvex shapes and asymmetric oval shapes (e.g., pumpkin seed shapes and sunflower seed shapes with generally pointed tails). In still further embodiments, such shapes generally include teardrop/teardrop shapes. In each embodiment, any combination of the aforementioned different shapes with different sizes can be provided as PVC filler particles, pellets, and granules in artificial turf equipment.

As shown in one embodiment of Fig. 1, the PVC-based granular material 5 used for the artificial turf filler includes various non-uniform shapes and sizes. Generally speaking, the granules are irregular, such as an asymmetric shape similar to seeds and/or droplets. The preferable PVC-based granular material 5 used in the embodiment of the present invention includes such PVC particles and pellets having the composition described in the '956 publication, which is incorporated herein by reference. Furthermore, the PVC-based granular material 5 can be manufactured according to conventional extrusion, granulation, and molding methods. In the embodiments of the present invention, PVC granules and pellets can be manufactured according to the methods described in the '956 publication and/or with reference thereto.

In one embodiment, the extrusion die 20 shown in FIGS. 2 and 3 can be used to manufacture PVC-based granular materials 5 having various shapes and sizes according to the present invention. Those skilled in the fields of extrusion, granulation and molding of PVC compositions will recognize that the manufacturing parameters (such as operating speed, Temperature settings, etc.) will depend on many factors, such as the specific machine used, the specific manufacturing environment, the precise composition of the PVC-based material, and similar variables. Therefore, the desired results of the partial manufacturing method for PVC-based fillers that conform to the shape and size of the present invention will be completely within the scope of those skilled in the relevant art, and are not considered essential to the present invention.

In an embodiment shown in FIGS. 2 and 3, the extrusion die 20 includes a ring of holes of different sizes, such as a ring of a first hole 30 , a ring of a second hole 32 , a ring of a third hole 34 , and a fourth hole Ring of 36 . Apertures having different sizes, so as to produce PVC-based pellet 5 and the various non-uniform and irregular shapes of various sizes. It will be understood that, in other embodiments of the present invention, the structure of the holes, the number of holes, the shape of the holes, the distance between the holes, and the alignment of the holes (whether it is a ring, a grid or other patterns) can be customized. The described embodiments are changed while still maintaining the production of irregular, non-uniform, and various sizes of PVC-based granular materials 5 .

In the embodiment of the present invention, compared with the uniform granular material disclosed in the '956 application, the use of irregular, non-uniform and various sizes of PVC granular material 5 gives artificial turf improved performance characteristics. In Tables I-III (test results will be described later), the uniform PVC-based filling granular material used for artificial turf according to the '956 application is called "20s/50TPE_PriorArt", which is used for artificial turf according to the embodiment of the present invention The non-uniform PVC filled granular material without abrasion simulation is called "70/30 Pre-Wear", and the non-uniform PVC filled granular material used in the artificial turf processed by the wear simulator of the Lisport brand abrasion machine is called It is "70/30 Post-Wear".

In order to compare the performance characteristics, each 20s/50TPE_PriorArt, 70/30 Pre-Wear and 70/30 Post-Wear pellets were provided to artificial turf and subjected to the following tests. Provide 20s/50TPE_PriorArt pellets in an artificial turf test system of 20 pounds of sand/50 pounds of thermoplastic elastomer (TPE) on 2½ inches of turf. Provides 70/30 Pre-Wear pellets in 4.97 pounds of PVC per square foot, 2.13 pounds of sand per square foot, 2.25 inches of slit film turf and artificial turf without liner test system. Provide 70/30 Post-Wear pellets in the test system of 4.97 pounds of PVC per square foot, 2.13 pounds of sand per square foot, 2.25 inches of cut film turf and artificial turf without liner, and use Lisport abrasion machine 20,000 cycles.

The following laboratory tests were performed on each pellet/artificial turf system sample. The technical guidelines of the Synthetic Turf Council (STC) are incorporated herein by reference. EN reference documents are European standards, which are also incorporated herein by reference.

Stress reduction (%)-(STC Advanced Artificial Athlete Protocol test) measures the shock absorption provided by the ground to the foot when the athlete runs. A lower value indicates a harder surface under the foot. Compare the results with the STC performance criteria (57% to 68% for public venues and 62% to 68% for stadium venues).

Vertical deformation (mm)-(STC Advanced Artificial Athlete Protocol Test) measures the amount of surface compression when athletes run across the surface. This value is usually related to movement speed and surface stability. Comparing the results with the STC performance criteria (6 mm to 11 mm for public venues and 6 mm to 10 mm for stadium venues), as the venue is used, the vertical deformation usually decreases over time.

Energy Recovery (%)-(STC Advanced Artificial Athlete Agreement Test) measures the percentage of recovered energy to applied energy, which can be considered as the elasticity of the surface. This value is related to the foot feeling and movement speed. Although this measurement is not part of the official standard, it is a useful measurement and the recommended range is 20% to 50%.

ASTM F355A Gmax/HIC Impact Attenuation (Falling Projectiles (missile)) (G's (Gravity Unit))-ASTM F355A Impact Hardness is the official equipment/method used to assess the hardness of synthetic turf sports fields based on a predetermined head/body Impact is used to estimate impact attenuation. This is a 20-pound "projection" with a three-axis accelerometer, falling from a height of 24 inches, STC recommends a Gmax value of less than 165.

EN 1177-HIC Impact Attenuation (Hemispherical Falling Projectiles) (Critical Falling Height (m))-EN 1177-Critical Falling Height Method The impact attenuation measurement of active pavement is similar to the method commonly used in the United States to evaluate sports field pavement. Internationally, it is the main method of synthetic turf and sports field paving. This device calculates the Head Injury Criteria (HIC), which is used to measure the possibility of head injury caused by surface impact. This device is a hemispherical 10-pound "projection" with a three-axis accelerometer. Drop the hemisphere from (4) different heights to determine the HIC as a height of 1000. This height is called the critical drop height. It is recommended that the critical drop height be greater than 1.3 meters.

Rotational resistance-EN15301 (Newton meters (n))-Rotational resistance measures the interaction between the cleat sole and the surface, and is related to the athlete's ability to change direction. The higher value is related to the surface where the athlete resists the rotation of the foot when changing direction, and will increase the possibility of lower limb injury. The STC guidelines recommend a result of 30n to 45n.

Vertical ball bounce-EN 12235 (meters (m))-measures the height of the ball bounced when it falls vertically into a synthetic turf field. Release the ball from 2 meters and calculate the height of its rebound from the surface. First, calibrate the ball to 1.35 meters on a horizontal concrete surface. The STC recommends 0.60 to 0.85 meters.

表II

表III

The following table I-III provides the test results of each kind of comparative granular material in various artificial turf systems conducted indoors: Table I

Table II

Table III

The test results listed in Tables I-III indicate that the embodiment of the present invention uses PVC filler pellets and granules of various sizes and irregular shapes, such as asymmetric shapes, which are dispersed in the form of fillers. Among the artificial turf equipment, the performance characteristics of the artificial turf provided are better than those of the conventional artificial turf equipment.

Various embodiments of the present invention have been described, however, it will be apparent that various modifications and changes can be made and additional additions can be made without departing from the broader scope of the exemplary embodiments set forth in the scope of the patent application. Implementation. This description should be considered illustrative and not restrictive.

5: PVC granular 20: Extrusion die 30: first hole 32: second hole 34: third hole 36: fourth hole

Figure 1 is a photograph of PVC filler pellets with different irregular shapes and different sizes in an embodiment of the present invention.

Figure 2 is a front view of a porous extrusion die with holes of different sizes, which is used to manufacture the PVC filler pellets shown in Figure 1 in an embodiment of the present invention.

Fig. 3 is a partial enlarged front view of the porous extrusion die of Fig. 2 in an embodiment of the present invention.

5: PVC granular

Claims (20)

An artificial turf comprising synthetic filamentous fibers or fiber simulation grass bonded to a backing and a filler, the filler having a layer of uneven, polyvinyl chloride granular particles dispersed between the filamentous fibers or fibers Where the granular material includes asymmetric shapes and different sizes. The artificial turf described in item 1 of the scope of patent application, wherein the granular material is at least one of pellets and granules. The artificial turf described in item 2 of the scope of patent application, wherein the granular material includes at least three different sizes. The artificial turf described in the third item of the scope of patent application, wherein at least some of the particulate matter includes an oval shape. The artificial turf described in item 3 of the scope of patent application, wherein at least some of the granular material includes an oval shape. The artificial turf described in item 3 of the scope of patent application, wherein at least some of the granular material includes an oblong shape. The artificial turf described in item 3 of the scope of patent application, wherein at least some of the granular materials include biconvex shapes. The artificial turf described in item 3 of the scope of patent application, wherein at least some of the granular materials include an asymmetric oval. The artificial turf described in item 3 of the scope of patent application, wherein at least some of the particulate matter includes a teardrop shape. The artificial turf described in item 3 of the scope of patent application, wherein the granular material includes a group selected from the group consisting of elliptical, oval, oblong, biconvex, asymmetric oval and teardrop shape Set of many different shapes. The artificial turf according to the second item of the patent application, wherein at least some of the granular material includes an oval shape. The artificial turf described in item 2 of the scope of patent application, wherein at least some of the granular material includes an oval shape. The artificial turf described in item 2 of the scope of patent application, wherein at least some of the granular material includes an obovate shape. The artificial turf as described in item 2 of the scope of patent application, wherein at least some of the granular material includes a biconvex shape. The artificial turf described in item 2 of the scope of patent application, wherein at least some of the granular material includes an asymmetric oval shape. The artificial turf as described in item 2 of the scope of patent application, wherein at least some of the particulate matter includes a teardrop shape. The artificial turf described in item 2 of the scope of patent application, wherein the granular material includes a group selected from the group consisting of elliptical, oval, oblong, biconvex, asymmetric oval and teardrop shape Set of many different shapes. The artificial turf as described in item 1 of the scope of patent application, wherein the granular material includes a group selected from the group consisting of elliptical, oval, oblong, biconvex, asymmetric oval and teardrop shape Set of many different shapes. The artificial turf described in item 18 of the scope of patent application further includes a sand-containing layer below the polyvinyl chloride-based granular material layer. The artificial turf described in item 1 of the scope of patent application further includes a sand-containing layer below the polyvinyl chloride-based granular material layer.

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