1. Field of the Invention
The present invention is directed toward synthetic turf systems, and more particularly toward synthetic turf sports surfaces. The present invention utilizes a synthetic turf system having an infill material atop a backing and interspersed between upwardly projecting monofilament ribbons simulating blades of grass, wherein the blades of grass have an improved appearance and performance.
2. Description of Related Art
Synthetic turf systems have been utilized for over forty years to provide a surfacing alternative where it is impossible, impractical, or simply undesirable to have a real grass surface. The more desirable synthetic turf systems on the market incorporate an infill material between upstanding blades of synthetic fibers that resemble blades of grass. The infill material enables a variety of features and characteristics to be imparted to the actual playing surface, while simultaneously enabling the synthetic fibers to retain a grass-like appearance. Thus, improved drainage, resiliency, predictability of sports play, reduction of injuries, and other advantages can be imparted to the synthetic turf surface, while maintaining an appealing appearance.
One particular function of the infill in a synthetic turf system is as a stabilizing force for the synthetic fiber blades. The synthetic blades in infill-type synthetic turf systems are relatively long (as compared to non-infilled systems); for example, between 1½-2½ inches long—so as to provide optimum surface “feel” and appearance. Therefore, to maintain these types of fibers in a substantially upright orientation, the infill material has been applied up to a pre-determined depth (or thickness), relative to the height of the fibers. In turn, the infill provides, amongst other things, a supportive base for the synthetic fibers.
The existence of a thickness of infill material incorporates its own problems, however. Infill materials preferably include a combination of particulate material, such as hard particles, a mixture of resilient and hard particles, or resilient particles alone. In turn, the particulate material can interfere with enjoyment of the synthetic surface by dislodging when struck by feet, played balls, or by direct contact with athletes. The dislodging of the infill is known generally as “infill splash.” The synthetic fiber blades help to diffuse and/or eliminate infill splash by, amongst other things, acting as a barrier for dislodging the infill materials, and by stabilizing the infill between the blades.
Conventionally, the combination of fiber-positioning and infill retention was accomplished, in part, through the use of relatively flexible slit-film-type polymeric blades. Such blades were typically woven or tufted into the backing layers of the synthetic grass surface, and then fibrillated into a web-like structure to maximize infill support and retention of the infill by the blades. Additionally, the free ends of these fibers would bend over the top of the infill to create an infill trapping effect. Unfortunately, such has resulted in problems in certain synthetic turf fields, including the tendency of these fibers to flatten out into a smooth surface without adequate grooming.
As an alternative to the slit-film type blade, monofilament blades can be utilized. Monofilament blades for synthetic grass are manufactured by extruding a resultant single polymer (or similar) blade from a device, such as a spinneret, into a long polymer strand, finishing that strand and then cutting single monofilament pieces from the strand. Typically, multiple monofilament elements are bound together at their base to create a single bundle of blades, which are then tufted into the backing layer of the synthetic grass surface, and fibrillated outwards.
One significant problem with the use of monofilament fibers in this manner, however, is the balance between the fiber characteristics needed for proper installation of the surface, and fiber characteristics that ensure the best surface conditions for game play and/or surface use. Typically, in order to properly install the infill on the synthetic grass surface, it has been necessary to utilize a relatively rigid/stiff monofilament fiber, so that the monofilament bundles are not buried under the infill as the infill is being applied.
After the infill has been applied to a desirable depth, the free ends of the monofilament fibers (those ends extending above the top of the infill) stand substantially upright. While this type of fiber positioning does offer some benefits—such as balls rolling closer to the way they would roll or bounce on a natural turf surface—it unfortunately also results in some undesired side effects. Specifically, unlike the free ends of softer fiber, which fold or bend over as a ball rolls over them, such an effect is not as prevalent when the stiffer fibers are used. Accordingly, as a ball rolls over the top surface of a synthetic playing surface using such relatively stiff fibers, the infill material becomes more easily displaced resulting in a significant amount of infill splash during game play.
On the other hand, the use of flexible fibers creates problems as well. While the fibers can help reduce infill splash during game play, they can make infill application more difficult during installation, and, can result in less than desirable resistance for ball roll and ball bounce during use. Similar to conventional carpet-type surfaces, rolling or bouncing balls are subjected to “sliding” issues on soft fibers surfaces. Sliding issues include unexpectedly proficient hops, a lack of grass-like roll response, and slippage on spinning balls when they contact the synthetic grass surface.
It is therefore an object of the present invention to overcome these and other issues associated with conventional synthetic turf systems. These and other objects will become apparent to one of ordinary skill in the art in light of the specification, claims, and drawings appended hereto.