ARTIFICIAL TURF WITH OPAQUE FACE YARN AND TRANSLUCENT THATCH YARN FIBERS

Abstract

An artificial turf includes translucent thatch yarn fibers and opaque face yarn fibers that are integrated in a carrier.

Claims

1. An artificial turf comprising: a carrier; translucent thatch yarn fibers integrated in the carrier; and opaque face yarn fibers integrated in the carrier.

2. The artificial turf of claim 1, wherein the length of the thatch yarn fibers is smaller than the length of the face yarn fibers.

3. The artificial turf of claim 1, wherein the translucent thatch yarn fibers are transparent.

4. The artificial turf of claim 1, wherein the artificial turf comprises two or more subregions, wherein all face yarn fibers contained in a subregion have the same color, which is different from the color of the face yarn fibers contained in all subregions adjacent to that subregion.

5. The artificial turf of claim 1, wherein the two or more subregions form a color pattern being selected from a group including: a logo of an organization; field markings and regions defined by the field markings; symbols of a game; and a pattern representing a text or an image.

6. The artificial turf of claim 1, wherein the face yarn fibers includes one or more pigments.

7. The artificial turf of claim 1, wherein the thatch yarn fibers are free of pigments.

8. The artificial turf of claim 1, wherein the thatch yarn fibers and/or the face yarn fibers are selected from a group comprising including polyethylene fibers, polyamide fibers, and polypropylene fibers.

9. The artificial turf of claim 1, wherein the thatch yarn fibers and/or the face yarn fibers are texturized.

10. The artificial turf of claim 1, wherein the thatch yarn fibers include a nucleating agent and the face yarn fibers are free of the nucleating agent or include a smaller amount of the nucleating agent than the thatch yarn fibers.

11. The artificial turf of claim 10, wherein the nucleating agent is an organic acid, an organic acid ester or organic acid salt.

12. The artificial turf of claim 10, wherein the nucleating agent is a salt of hexahydrophthalic acid, sorbic acid or salicylic acid, in particular a calcium salt of hexahydrophthalic acid.

13. A layered surface structure comprising: a display layer; and an artificial turf including translucent fibers, the artificial turf being placed on top of the display layer; wherein the display layer includes one or more display elements adapted to emit light signals toward the artificial turf.

14. The layered surface structure of claim 13, the artificial turf being an artificial turf including: a carrier; translucent thatch yarn fibers integrated in the carrier; and opaque face yarn fibers integrated in the carrier.

15. A method of manufacturing an artificial turf comprising: providing a carrier; integrating translucent thatch yarn fibers in the carrier; and integrating opaque face yarn fibers in the carrier.

16. A method of manufacturing a layered surface structure comprising: providing a display layer including one or more display elements; placing an artificial turf including translucent fibers on top of the display layer; wherein the display elements are adapted to emit light signals toward the artificial turf.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In the following, embodiments of the invention are explained in greater detail, by way of example only, making reference to the drawings in which:

[0049] FIG. 1 depicts a 3D model of an art artificial turf according to an embodiment of the invention.

[0050] FIG. 2 depicts a cross-sectional view of an artificial turf according to an embodiment of the invention.

[0051] FIG. 3 depicts a region of FIG. 2 in greater detail.

[0052] FIG. 4 depicts an artificial turf according to a further embodiment.

[0053] FIG. 5 depicts an artificial turf according to a further embodiment.

[0054] FIG. 6 depicts an artificial turf according to a further embodiment.

[0055] FIG. 7A depicts a flowchart of a method of producing artificial turf according to an embodiment of the invention.

[0056] FIG. 7B depicts a flowchart of a method of producing a layered surface structure according to an embodiment of the invention.

[0057] FIG. 8 depicts tuft rows of an artificial turf according to an embodiment of the invention.

[0058] FIG. 9 depicts tuft rows of an artificial turf according to a further embodiment of the invention.

[0059] FIG. 10 depicts a layered surface structure according to an embodiment of the invention.

[0060] FIG. 1 depicts a virtual 3D model 100 of an art artificial turf according to an embodiment of the invention. It comprises straight, non-texturized face yarn fibers 102 having a pile height L3, and a zone of texturized thatch yarn fibers 104. The thatch yarn fibers have a height L2 that is shorter than the height L3 of the face yarn fibers. The difference between the height of the face yarn fibers and of the thatch yarn fibers is depicted as L1. The thatch yarn fibers and face yarn fibers are integrated into a carrier structure 106, e.g., a fiber mesh. The fiber mesh can be made of synthetic and/or natural fibers. In some embodiments, the fiber mesh is created by interweaving the face yarn fibers with each other such that the forming of the mesh and the integration of the face yarn fibers is performed in a single operation. According to other embodiments, the carrier mesh 106 is provided first and the fibers 102, 104 are integrated into the existing carrier mesh 106 in subsequent steps.

[0061] Optionally, the artificial turf can comprise a backing layer below the carrier 106 (not shown). The backing layer may consist of polyurethane (PU) or latex and may be used for firmly fixing the fibers 102, 104 in the carrier 106.

[0062] In the embodiment depicted in FIG. 1, the artificial turf further comprises infill 110. The infill can be, for example, an elastic granulate such as rubber granulate, cork granulate, etc., and/or inelastic particles such as sand or zeolite or a mixture thereof.

[0063] The whole artificial turf comprising the fibers 102, 104, the carrier 106, the optional filler and the backing (if any) can be placed on top of a base layer 108. The base layer can also be referred to as ground layer or substrate layer. For example, the base layer can be made of concrete, soil, stone, or similar. It is also possible that the base layer is a manmade flooring layer, e.g., a layer comprising electronic elements such as LED panels or other display devices. The manmade layer can also be an elastic layer, e.g., a PU layer comprising rubber particles.

[0064] The face yarn fibers in the artificial turf model 100 have a green color such that natural grass fibers are faithfully reproduced. The thatch yarn fibers in the 3D model are depicted in a brighter color in order to better illustrate their height, position, and texturization. However, FIG. 1 merely depicts a virtual model. The thatch yarn fibers of an artificial turf according to embodiments of the invention actually are translucent and hence cannot be identified as clearly as indicated in the computer-generated model depicted in FIG. 1.

[0065] FIG. 2 is a photo of a cross-sectional view of an actual artificial turf 200 according to another embodiment of the invention. The artificial turf 200 comprises red, non-texturized face yarn fibers 102 and translucent, colorless, texturized thatch yarn fibers 104. In addition, the artificial turf comprises infill granules 110 in the form of rubber granules. The rubber granules can be coated and the coating can comprise pigments, e.g., dark or brownish pigments to give the color impression of sand or soil. The filler material 110 can likewise be, for example, a sand-rubber-granule mixture. The infill may fill free space between thatch yarn fibers and/or face yarn fibers. The infill height can be smaller than the thatch yarn length L2, or can be a height between L2 and L3. In one embodiment, the upper surface of the infill layer is one or more cm below the pile height L3. Thanks to a combination of face yarn fibers and thatch yarn fibers, the infill granules are stabilized and are protected from being delocalized by a ball or other object hitting the surface of the artificial turf.

[0066] The texturization of the thatch yarn fibers may result in a random orientation of the thatch yarn fibers and an intertwining of the face yarn fibers and the thatch yarn fibers. This may help to mechanically fix the infill granules between the thatch yarn fibers, thereby reducing the loss of infill material that may be caused by rainfall, wind, and impacting objects, e.g., a ball or a foot of a player. The thatch yarn fibers depicted in FIG. 2 are not only translucent but also transparent.

[0067] The thatch yarn fibers can be textured or nontextured. Likewise, the face yarn fibers can be textured or nontextured fibers. The texturization of fibers, in particular of the thatch yarn fibers 104, may provide for a random orientation of the textured fibers in the artificial turf. This provides an artificial turf with a more homogeneous surface that increases the predictability and directional stability of any object rolling or sliding over the surface of the artificial turf.

[0068] FIGS. 1 and 2 show the texturized thatch yarn fibers 104 in their relaxed, default state. The length of the fibers in this state is shorter than in a stretched, expanded state, due to their texturization.

[0069] The fibers 102, 104 can be monofilaments or split film tapes or bundles of monofilaments or split film tapes. Preferably, the fibers of the face yarn are made of a mixture of PE/PA with compatibilizer as disclosed in EP 3122942. Surprisingly PE/PA monofilaments have the following advantages in this context: the PE provides for a soft, elastic surface that protects the skin of the players from injury. The PA increases the rigidity and thus ensures that the fibers re-erect after being trampled down. If the fiber is a textured fiber, the use of a PE/PA mixture or blend may ensure that the texturing has more long term stability even if subjected to mechanical stress and weathering (sunshine).

[0070] According to some embodiments, the thatch yarn fibers can be made of PE monofilaments (in particular LLDPE) or another material as it is less stressed both mechanically and by weathering. Moreover, thatch yarn lacking PA may shrink more if exposed to heat. This effect may be used for generating an artificial turf with two types of texturized fibers that are adapted to form a thatch yarn zone of a clearly defined, uniform fiber height L2, and for generating face yarn fibers having a defined, uniform fiber height L3 although the face yarn fibers may be texturized.

[0071] The thatch yarn fibers and the face yarn fibers can be made of the same type of polymer, e.g., PE, or of a mixture of miscible polymers, or a polymer mixture of immiscible polymers. For example, the polymer mixture used for generating the face yarn or thatch yarn fibers can be a three-phase system, wherein the polymer mixture comprises a first polymer, a second polymer, and a compatibilizer. The first polymer and the second polymer are immiscible. The first polymer forms polymer beads surrounded by the compatibilizer within the second polymer as disclosed in EP 3122942 the entirety of which being expressly herein incorporated by reference. The second polymer may be a PE and the first polymer can be PA. The polymer mixture used for generating the first fibers to be turned into thatch yarn fibers can be made of PE that is free of any PA. The PA beads may provide some stability and rigidity to the fibers, thereby reducing the ability of the second fibers to contract, e.g., in response to heat.

[0072] The face yarn fibers and thatch yarn fibers can be integrated into the carrier, e.g. by gluing, weaving, or tufting the fibers into the carrier.

[0073] The face yarn fibers 102 define the pile height L3 of the artificial turf and provide the rolling resistance for the rolling ball. The thatch yarn fibers 104 serve the purpose of holding or immobilizing the infill, if any, and prevent or reduce splashing and limit redistribution of the infill when the artificial turf is in use, thereby preventing an uneven distribution of the infill.

[0074] FIG. 3 depicts a region 202 of FIG. 2 in greater detail. FIG. 3 illustrates that the thatch yarn fibers of some embodiments are not only translucent, but also transparent, meaning that not only the color of the face yarn fibers, but also the contours of the face yarn fibers are visible through a thatch yarn fiber.

[0075] FIG. 4 depicts an artificial turf 400 according to a further embodiment. The artificial turf 400 comprises non-texturized face yarn fibers 102 and texturized thatch yarn fibers 104.

[0076] FIG. 5 depicts an artificial turf 500 according to a further embodiment. The artificial turf 500 comprises texturized face yarn fibers 102 and texturized thatch yarn fibers 104.

[0077] FIG. 6 depicts an artificial turf 600 according to a further embodiment. The artificial turf 500 comprises texturized face yarn fibers 102, texturized thatch yarn fibers 104, and a filler 110 that is mechanically stabilized by the face yarn fibers and the thatch yarn fibers.

[0078] The side of the carrier 106 from which the fibers 102, 104 protrude is referred to herein as the upper side of the carrier/of the artificial turf, while the other side, where only u-shaped portions of the fibers forming tuft knots and/or a secondary backing may be visible, is referred to herein as the lower side of the artificial turf.

[0079] FIG. 7A depicts a flowchart of a method of producing artificial turf 200, 400, 500, 600, 800, 900 according to an embodiment of the invention.

[0080] In step 702, a carrier 106 is provided. The carrier can be a textile carrier, e.g., a fiber mesh made of synthetic and/or natural fibers. The carrier can be provided by feeding the carrier into a machine that is configured for integrating fibers into the carrier. The machine can be, for example, a tufting machine.

[0081] In step 704, translucent thatch yarn fibers 104 are integrated in the carrier. For example, the thatch yarn fibers can be tufted, knitted, woven, glued, or otherwise integrated into or attached to the carrier.

[0082] In step 706, opaque face yarn fibers 102 are integrated in the carrier. For example, the face yarn fibers can be tufted, knitted, woven, glued, or otherwise integrated into or attached to the carrier.

[0083] In some embodiments, the face yarn fibers are integrated earlier than the thatch yarn fibers. In other embodiments, the thatch yarn fibers are integrated earlier than the face yarn fibers. In still other embodiments, the face yarn fibers and the thatch yarn fibers are integrated basically at the same time. For example, the thatch yarn fibers and the face yarn fibers can be tufted into the carrier by different tufting machine or by a tufting machine comprising two or more different tufting needles.

[0084] According to embodiments, the integration of the fibers is performed such that the machine or machine component that performs the integration of the face yarn fibers replaces the face yarn having a first color that was previously used for integration by another face yarn having a second color when the machine crosses a subregion border of the artificial turf. The machine or machine component that performs the integration of the thatch yarn fiber maintains (does not replace) the thatch yarn that was previously used for integration by another thatch yarn when the machine crosses a subregion border of the artificial turf.

[0085] This may significantly ease and accelerate the process of integrating fibers when manufacturing artificial turf that comprises complex patterns of multiple different colors.

[0086] FIG. 7B depicts a flowchart of a method of producing a layered surface structure 950 as depicted, for example, in FIG. 9.

[0087] In step 750, a display layer 952 comprising one or more display elements is applied. The display layer can be installed on a base layer made of a natural material such as soil, wood, or stone or on top of a base layer made of another type of material such as concrete, polyurethane, acrylic resin or similar. The layered structure can be an indoor or an outdoor flooring, e.g., a playing surface of a sports field or playground. In particular, the surface structure can be an interactive playing surface, e.g., an interactive gym floor, soccer floor, golf course, tennis field, or similar. The application of the display layer can comprise installing the display elements at the use site, e.g., connecting the display elements with one or more control units and with a power source.

[0088] Then in step 752, an artificial turf is applied on top of the display layer. The artificial turf is an artificial turf as described herein for embodiments and examples of the invention and as depicted, for example, in FIGS. 2, 3, 4, 5, 6, 8, and 9. The artificial turf can be placed directly on top of the display layer. Alternatively, one or more translucent, preferably transparent material layers can be applied on top of the display layer before the artificial turf is applied. For example, a glass layer or a polymer foil layer can be applied in order to better protect sensitive electronic components of the display elements from impacting objects.

[0089] The display elements can be electronic display elements adapted to visually represent and display information and emit light signals in the direction to the artificial turf, i.e., in an upward direction. In some embodiments, the display elements are configured to emit light in basically all directions. However, preferably, the display elements are configured to emit the majority of the light in basically an upward direction to save energy and costs. It needs to be ensured that at least the players using the surface structure and also the audience can see the light intensity and/or color pattern generated by the light emitted by the display elements.

[0090] FIG. 8 depicts tuft rows 802, 804 of an artificial turf 800 according to an embodiment of the invention. In the depicted embodiment, texturized face yarn fibers and texturized thatch yarn fibers are tufted in straight parallel rows. Thatch yarn fiber rows (B), 802 and face yarn fiber rows (A) 804 are alternating in the plane of the artificial turf. The face yarn fibers are longer than the thatch yarn fibers. The fibers are integrated into the carrier mesh by a tufting process, whereby bundles of fibers of the same type are tufted into the carrier and are then cut. Each row 802, 804 comprises only fibers of one particular type, i.e., either thatch yarn fibers or face yarn fibers.

[0091] The distance between tufting rows of the same fiber type can be e.g., 1.9 cm and can be about 0.95 cm between neighboring rows of face/thatch yarn.

[0092] FIG. 9 depicts another artificial turf 900 wherein texturized face yarn fibers and texturized thatch yarn fibers are tufted in parallel, zigzag rows. Thatch yarn fiber rows 902 and face yarn fiber rows 904 are alternating in the plane of the artificial turf. Each row comprises only fibers of one particular type, i.e., either thatch yarn fibers or face yarn fibers.

[0093] Using texturized face yarn fibers reduces the anisotropy of the roll resistance of the artificial turf. Zigzag rows are particularly advantageous in this context as they reduce the anisotropy of the roll resistance of the artificial turf even more.

[0094] According to further embodiments (mixed type tuft rows, not shown), face yarn fibers and thatch yarn fibers are tufted in parallel, mixed type (or mixed) rows. Each row comprises a mixture of both texturized face yarn fibers and texturized thatch yarn fibers. For example, each row may comprise a mixture of thatch yarn fiber bundles and face yarn fiber bundles. Alternatively, each row may comprise a mixture of face and thatch yarn fibers that are individually tufted into the carrier. Still alternatively, each row may comprise tuft bundles respectively comprising a mixture of thatch yarn fibers and face yarn fibers.

[0095] FIG. 10 depicts a layered surface structure 950 according to an embodiment of the invention. The surface structure comprises a display layer 952 and an artificial turf 960 on top of the display layer.

[0096] The display layer comprises a plurality of display elements 954, e.g., LED light spots or stripes. Each of the display elements can be connected to one or more control units, e.g., one or more remote or local control computers. The control units cause the display elements to light up to display patterns of different light intensity and/or color on. These patterns can relate to line markings for different sports. For example, the display elements can be LED lights underneath a transparent or translucent layer, e.g., a glass floor. The dynamic displaying of the line markings may allow supporting many different types of sports such as tennis, handball, volleyball, basketball, and badminton by a single playing surface structure. For example, the display layer can comprise a plurality of single glass panels layered with foil and comprising bright LED or OLED spots or stripes whose intensity and/or color can be controlled by the control unit(s) individually.

[0097] The artificial turf 960 comprises translucent fibers 956. Preferably, the fibers 956 are transparent fibers, e.g., transparent PE fibers that can be texturized or non-texturized fibers. According to some embodiments, all fibers 956 of the artificial turf 960 are translucent, e.g., transparent, fibers. This may have the advantage that the light emitted by the display layer is not, or not significantly, weakened or absorbed by the artificial turf. However, this type of artificial turf is not suited for representing and comprising a graphical pattern, e.g., a logo, because the fibers basically do not modify the wavelength composition of the light passing through the fibers. According to other embodiments, the artificial turf comprises the transparent fibers 956 in addition to opaque fibers. For example, the artificial turf 950 can be an artificial turf as described herein for embodiments and examples of the inventive artificial turf, e.g., a turf 100, 200, 400, 500, 600, 800, 900 illustrated in FIGS. 1, 2, 4, 5, 6, 8, and 9. This may have the advantage that some patterns can be generated by the display layer while other patterns can be generated based on color differences of the opaque face yarn fibers. For example, the color of the pigments of different face yarn fibers can be used for defining permanent patterns in the artificial turf, e.g., line markings or a logo of a club owning the surface structure 950 while the light emitted selectively by some display elements of the display layer may define line markings that may be changed dynamically based on the type of game to be played. However, it is also possible that the line markings, for example, are defined permanently via pigment differences of face yarn fibers and the display elements are used for displaying dynamically modifiable patterns such as the logo of the invited club, an ad, a text with information for visitors, or the like.

[0098] The face yarn fibers 102 of the artificial turf 200 may absorb some of the light emitted by the display elements 954, but a significant portion of the light will pass through the artificial turf layer because the translucent thatch yarn fibers ensure that the light is not completely absorbed or blocked by the face yarn fibers. The thatch yarn fibers, in particular if textured, will occupy space and thus ensure that some regions of the artificial turf allow light to pass through.

LIST OF REFERENCE NUMERALS

[0099] 100 3D model of artificial turf [0100] 102 face yarn fibers [0101] 104 thatch yarn fibers [0102] 106 carrier [0103] 108 base layer [0104] 110 filler material [0105] L2 length of thatch yarn fibers [0106] L3 length of face yarn fibers [0107] L1 difference of L2 and L3 [0108] 200 artificial turf [0109] 202 selected region of artificial turf 200 [0110] 400 artificial turf [0111] 500 artificial turf [0112] 600 artificial turf [0113] 702-706 steps [0114] 750-752 steps [0115] 800 artificial turf [0116] 802 tuft row comprising thatch yarn fibers [0117] 804 tuft row comprising face yarn fibers [0118] 900 artificial turf [0119] 902 tuft row comprising thatch yarn fibers [0120] 904 tuft row comprising face yarn fibers [0121] 950 layered surface structure [0122] 952 display layer [0123] 954 display element [0124] 956 translucent fiber [0125] 960 artificial turf