ARTIFICIAL TURF

Abstract

An artificial turf contains a damping layer made of a particle foam, a fiber backing, and an artificial grass layer made of single or multiple fibers. The fibers are tied to the fiber backing, forming an artificial carpet of grass. The particle foam and the single or multiple fibers forming the artificial grass layer are each made of a thermoplastic elastomer.

Claims

1. An artificial turf, comprising: a damping layer made of a particle foam, a fiber backing, and an artificial grass layer made of single or multiple fibers, the fibers being tied to the fiber backing forming an artificial carpet of grass, wherein the particle foam and the fibers forming the artificial grass layer each are made of a polymer which comprises a thermoplastic elastomer.

2. The artificial turf according to claim 1, wherein the fiber backing also is made of a thermoplastic elastomer.

3. The artificial turf according to claim 1, wherein the particle foam, the fiber backing and the single or multiple fibers forming the artificial grass layer are each made of a thermoplastic elastomers composed of the same monomer units respectively or from the same components in case of a compound structure, and wherein different characteristics of the layers are established by variation in the ratio of hard phases and soft phases in the thermoplastic elastomer, and optionally by variation in added additives in each thermoplastic elastomer.

4. The artificial turf according to claim 1, wherein the particle foam is formed from expanded beads which are connected in such a way that passages form between the expanded beads which allow water to drain through the damping layer.

5. The artificial turf according to claim 4, wherein the expanded beads of the particle foam are connected by gluing or by welding.

6. The artificial turf according to claim 1, wherein the fiber backing is a woven fabric, a knitted fabric, a crocheted fabric, a laid textile, a mat, a foil or a nonwoven fabric.

7. The artificial turf according to claim 1, wherein the fibers of the artificial grass layer have different lengths forming long blades of grass and short blades of grass.

8. The artificial turf according to claim 1, wherein the artificial carpet of grass comprises blades of grass which are straight upright and blades of grass which are curled.

9. The artificial turf according to claim 1, wherein the fiber backing is connected to the damping layer by gluing or welding.

10. The artificial turf according to claim 9, wherein for gluing the fiber backing on the damping layer an adhesive is used which is composed of the same monomer units as the polymer the fiber backing is made of.

11. The artificial turf according to claim 1, wherein the thermoplastic elastomer is a thermoplastic polyolefin elastomer (TPO), a thermoplastic vulcanizate (TPV), a thermoplastic styrenic block copolymer (TPS) or compound, a thermoplastic polyurethane (TPU), a thermoplastic copolyester (TPC) or a thermoplastic polyamide (TPA).

12. An artificial lawn, composed of at least two modules made of the artificial turf according to claim 1.

13. The artificial lawn according to claim 12, wherein adjacent modules are plugged into each other.

14. The artificial lawn according to claim 13, wherein adjacent modules are glued or welded to each other.

15. The artificial lawn according to claim 12, wherein the at least two modules have a size which allows to roll them for forming coils for transportation.

Description

[0052] Illustrative embodiments of the invention are shown in the figures and explained in more detail in the following description.

[0053] In the figures:

[0054] FIG. 1 shows a cross sectional view of an artificial turf in a first embodiment,

[0055] FIG. 2 shows a cross sectional view of an artificial turf in a second embodiment,

[0056] FIG. 3 shows a cross sectional view of an artificial turf in a third embodiment,

[0057] FIG. 4 shows an artificial lawn.

[0058] FIG. 1 shows an artificial turf in a first embodiment.

[0059] An artificial turf 1 is composed of a damping layer 3, a fiber backing 5 and an artificial grass layer 7. The damping layer 3 is formed from a particle foam which is composed of expanded beads 9 which are connected one to another. The expanded beads are made from a thermoplastic elastomer, particularly from a thermoplastic polyurethane (TPU). For producing the particle foam, in a first step expanded beads are produced. These beads then are connected to one another usually in a die under pressure. The pressure depends on the intended density of the particle foam. For connecting the expanded beads 9, the expanded beads 9 can be glued by using an adhesive or welded. Welding the expanded beads 9 by passing hot steam through the die is preferred. However, if an adhesive is used for gluing the expanded beads, it is preferred to use an adhesive which is composed of the same monomer units as the polymer used for producing the expanded beads 9.

[0060] Preferably, the expanded beads 9 are connected such that passages 10 form between the beads. Such passages 10 allow draining of water which is particularly preferred in case the artificial turf 1 is used in outdoor applications to avoid forming puddles on the artificial turf 1.

[0061] To the damping layer 3 a fiber backing 5 is fixed. For fixing the fiber backing 5 on the damping layer 5, it is possible to weld the fiber backing 5 on the damping layer 3 or to glue the fiber backing 5 on the damping layer 3. To avoid adding an additional polymer, also for fixing the fiber backing 5 on the damping layer 3 welding is preferred. If an adhesive is used, also for gluing the fiber backing 5 on the damping layer 3 it is preferred to use an adhesive which is composed of the same monomer units as the polymer used for producing the expanded beads 9.

[0062] To allow fibers for forming the artificial grass layer 7 being connected to the fiber backing 5, the fiber backing is a woven fabric, knitted fabric, crocheted fabric, laid textile, mat, foil or nonwoven fabric.

[0063] Further, also the fiber backing 5 is produced of a polymer which is composed of the same monomer units as the polymer of the expanded beads 9. Using polymers being composed of the same monomer units has the advantage that recycling without separating and sorting the layers is possible.

[0064] In FIG. 1, the artificial grass layer 7 comprises blades of grass 11, which are made of fibers all having the same length. The fibers are connected to the fiber backing 5 thus forming the artificial grass layer 7. Connecting the fibers for forming the blades of grass 11 to the fiber backing 5 preferably is carried out by knotting or by tufting.

[0065] For allowing recycling without separating and sorting, also the fibers used for forming the blades of grass 7 are produced of a polymer which is composed of the same monomer units as the damping layer 3 and the fiber backing 5.

[0066] FIG. 2 shows an artificial turf 1 in a second embodiment.

[0067] The artificial turf 1 of FIG. 2 differs from the artificial turf of FIG. 1 only in the artificial grass layer 7. In FIG. 2, the artificial grass layer 7 is composed long blades of grass 13 and short blades of grass 15. The different length of grass can be achieved by using different fiber lengths for the fibers forming the blades of grass or by firstly forming the short blades of grass 15 and in a second step the long blades of grass 13. This is particularly preferred, when for forming the blades of grass loops are formed which then are cut into the separate blades of grass during the tufting process.

[0068] As for the artificial turf shown in FIG. 1, also for the artificial turf shown if FIG. 2 it is particularly preferred if all layers are formed of thermoplastic elastomers which are composed of the same monomer units respectively from the same components in case of a compound structure, and to employ the different characteristics particularly by variation of the soft phases and hard phases and optionally additionally by adding additives.

[0069] FIG. 3 shows an artificial turf 1 in a third embodiment.

[0070] In difference to the artificial turf 1 in FIG. 2, the artificial turf 1 of FIG. 3 comprises long blades of grass 13 and curled blades of grass 16. The curled blades of grass 16 for example can be produced of a polymer having a composition such that the polymer curls on a temperature treatment. In this case, the artificial carpet of grass comprising the fiber backing 5 and the blades of grass 13, 16 is formed with all blades being smooth. After producing, for example by tufting, the artificial carpet of grass is subjected to a temperature treatment such that some of the blades of grass made of the polymer which curls on temperature treatment curl and form a layer of curled blades of grass 16 which supports the smooth long blades of grass 14 standing upright.

[0071] Besides curling a part of the blades of grass by a temperature treatment, it is also possible to produce curled or crinkled monofilaments which are used as curled blades of grass 16. However, for facilitating the production process it is preferred to use two kinds of polymer, one which keeps smooth on a temperature treatment and one which curls on temperature treatment.

[0072] FIG. 4 shows a top view of an artificial lawn.

[0073] An artificial lawn 17 is formed of several modules 19, each of the modules 19 made of an artificial turf as shown in one of figures1, 2 or 3. By forming the artificial lawn 17 using a plurality of modules 19, it is possible to provide a large area with the artificial lawn 17 but keeping the artificial lawn 17 transportable if it shall not be outlaid permanently.

[0074] To avoid slipping of the modules 19 and thereby forming gaps between the modules 19 it either is possible to weld or glue the modules one to another or to plug adjacent modules 19 into each other. Gluing or welding only is suitable if the artificial lawn is outlaid permanently. For a transportable artificial lawn 17, it is preferred to plug adjacent modules into each other. For plugging the modules 19 into each other it is preferred to provide the edges 21 of the modules 19 with undercuts 23 which engage. By the engaging undercuts a detachable but stable connection of the modules 19 can be achieved.

[0075] As shown in FIG. 4, the undercut 23 for example can be achieved by T-shaped extensions 25 or L-shaped extensions 27 which can be plugged into each other. Besides the T-shaped or L-shaped extensions any other shape having an undercut can be used, for example also a shape like a piece of a puzzle.

[0076] The extensions which are used to plug adjacent modules 19 into each other in FIG. 4 are only shown exemplary. Usually only one type of extensions will be provided for one artificial lawn 1. If different extension will be used, it is preferred to provide each module with the same extensions to facilitate outlaying the modules 19. However, particularly in case a specific order of the modules is necessary, for example for outlaying a pattern of the artificial lawn, it is advantageous to provide different extensions on each edge to ensure that each module 19 is placed to the correct position.