Corn cob-based infill material for synthetic turf fields

Abstract

Infill composition for artificial turf fields comprising at least one layer of particles comprising woody strip corn-based particles, comprising a particle size distribution with an initial dry size of 0.5 to 5 mm and a final size of 0.6 to 7 mm after wetting. The composition can be installed by spreading a layer of dry woody strip corn-based particles onto a provided mat on a compacted stone base; watering the particle layer so that the dry particles expand after watering; brushing the particle layer; and decompacting the particle layer so that the woody strip corn-based particles are evenly distributed over the mat.

Description

CORN COB-BASED FILL MATERIAL FOR FIELDS SYNTHETIC TURF Background of the invention

[0001] Artificial turf fields are composed of three primary components, from bottom to top: impact pad, infill, and ground cover. These components are generally mounted on a compacted stone base. The impact pad is optional and provides much of the field's shock absorption performance, required for the safety of players in the event of an impact. The ground cover mimics the blades of grass and the root zone, providing the surface's softness and traction, as well as many of the ball interaction properties.The infill is generally made up of at least two layers, the lower layer of which serves to hold and stabilize the carpets on which it is placed, while the upper layers serve as an additional interface layer for the people playing on the field, providing surface softness, friction, traction and much of the mechanical properties of the field that are directly perceived by the players.

[0002] The stabilizing infill is usually sand. It serves to hold the turf in place and provides a more compact and solid base that gives the overall turf a good traction. Other materials have also been used in the past as stabilizing infill, but their use remains limited due to the good performance, widespread availability, and low cost of sand for this purpose.

[0003] The top filler layers have most frequently comprised styrene-butadiene rubber (SBR) particles due to the availability of rubber at the end of the service life of automobile tires, and in many parts of the world this continues to be the most widely used filler material because of its shock-absorbing properties and its ease of combination with other materials in a complete system. Other types of rubber, such as ethylene-propylene-diene monomer (EPDM) rubber, are also used for this purpose, as they are generated as waste from other industries and can be processed to provide performance filler with advantageous properties; other thermoplastics, such as polyvinyl chloride (PVC), have also been used with a similar effect.It is possible to use composite materials that combine thermoplastics, elastomers, reinforcements and / or fillers to obtain additional properties that are difficult to obtain with monolithic materials.

[0004] Growing environmental and sustainability concerns have recently led to the use of alternative materials to replace plastic and rubber fillers. One approach to addressing these environmental issues has been the production of biodegradable plastic fillers. However, these materials are difficult and expensive to produce to achieve the desired properties and in the required quantities.

[0005] The other major approach aimed at mitigating environmental problems has been the use of biological materials—of microbial, plant, or animal origin—as infill. Cork has been the most common of these materials used as a performance infill. Cork can provide mechanical performance characteristics, but its low density makes transportation costly, and it can also float away from the field margins in heavy rain. Cork also has relatively low wear resistance and limited availability due to long production times and a limited growing area. Pulverized olive pits provide mechanical strength and are available at low cost, but they have a high coefficient of friction that often impairs player comfort.Coconut fiber exhibits good mechanical performance but requires consistent watering to maintain its properties and yield. Mixed organic materials have also been used as high-performance fillers. In the past, conventional organic fillers using corn cobs, either alone or in combination with other materials, were used in an attempt to mitigate some of the identified drawbacks. Previous use of corn cobs involved granulated corn, resulting in rapid darkening and degradation of the material, as well as the undesirable effect of attracting wildlife to the field. SUMMARY

[0006] The following is a simplified summary to provide a basic understanding of some aspects of the disclosed object. This summary is not a comprehensive overview. It is not intended to identify key / critical elements or delimit the scope of the claimed object. Its sole purpose is to introduce some concepts in a simplified form as a preamble to the more detailed description presented later.

[0007] There remains a need for environmentally friendly and ultimately biodegradable fill materials with good mechanical properties and strength, while also being highly available, easy to transport and low cost.

[0008] In some aspects, a woody strip corn infill uses a shock-absorbing pad to achieve desired and / or appropriate shock absorption in the turf. Woody strip corn infill is most often installed over a sand layer, in which the sand acts as a stabilizing infill. As a stabilizing infill, the sand functions as a ballast layer that supports the turf and reduces movement.

[0009] In other respects, an infill composition for artificial turf fields comprises at least one layer of woody strip corn-based particles. The woody strip corn-based particles include a granulometric distribution with an initial dry size of approximately 0.5 to 5 mm and a final size of approximately 0.6 to 7 mm after wetting. The infill can be installed by spreading a layer of woody strip corn-based particles over a carpet that is on a compacted stone base, wherein the layer of woody strip corn-based particles includes or consists of dry particles. The layer of woody strip corn-based particles is then sufficiently watered so that the dry particles expand after absorption.The woody strip corn-based particle layer is brushed and loosened so that the woody strip corn particles are evenly distributed over the turf system. As mentioned previously, a shock-absorbing pad is often used to achieve the desired shock absorption.

[0010] To achieve the above and related objectives, this specification describes certain illustrative aspects of the claimed object with respect to the following description and accompanying drawings. These aspects indicate various ways of implementing the object, all of which fall within the scope of the disclosed object. Further advantages and novel features may become apparent from the following detailed description when considered in conjunction with the drawings.

[0011] These and other systems, methods, objectives, features and advantages of the present disclosure will become evident to those skilled in the art from the following detailed description of the preferred embodiment and the drawings.

[0012] All documents mentioned in this report are incorporated herein by reference. References to singular items include plural items, and vice versa, unless explicitly stated otherwise or made clear from the text. Grammatical conjunctions are intended to express all disjunctive and conjunctive combinations of sentences, phrases, words, and the like, unless otherwise stated or made clear from the context. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 illustrates a turf carpet system featuring a corn-based material infill according to some embodiments of the present disclosure.

[0014] Figure 2 illustrates a turf carpet system featuring a fill made of corn-based material and sand in separate layers according to some embodiments of the present disclosure.

[0015] Figure 3 illustrates a turf carpet system featuring a fill made of corn-based material and sand in a mixed layer according to some embodiments of the present disclosure. Detailed implementation methods

[0016] The following describes various aspects of this disclosure in greater detail by reference to the accompanying drawings, in which similar numbers generally refer to similar or corresponding elements throughout the disclosure. However, it should be understood that the drawings and the related detailed descriptions are not intended to limit the claimed subject matter to the particular form disclosed. In fact, the intention is to cover all modifications, equivalents, and alternatives that fall within the spirit and scope of the described and claimed subject matter.

[0017] An artificial turf system may utilize an infill material that includes material derived from the woody strip of a corn cob. In some cases, a stabilizing layer, such as sand or other suitable material, is incorporated. In addition, and more frequently, a shock-absorbing pad is used to achieve the desired shock absorption for a particular installation / purpose. The infill material provides many of the mechanical properties that are desirable for use as artificial turf infill and offers performance advantages over the materials and methods described above.

[0018] As indicated, the woody strip corn infill material can be used in combination with a shock-absorbing pad, carpet, and / or a stabilizing infill layer (e.g., sand) to form the artificial turf system. The artificial turf system, which utilizes the described infill material, exhibits superior mechanical performance, increased mechanical durability, easy availability, and mitigates or prevents flotation problems when subjected to large amounts of water.

[0019] In addition to its excellent field performance, this woody corn cob strip-based material also exhibits behaviors that require unique installation methods. Specifically, the material shows a significant amount of expansion after initial exposure to water due to the processing and drying method, resulting in an expandable, water-absorbent, and elastic fill material.

[0020] Installation Procedure

[0021] In some embodiments, for example, for field installations, the infill material may include a bottom layer of sand and a top layer of the woody strip corn infill material. In other embodiments, the woody strip corn infill material may be applied in a single layer. By way of example only, the woody strip corn infill material may be used in a single layer, for example, in areas where the layer depth is 15 mm or less. Similarly, the woody strip corn infill material may be applied in two layers, for example, in installations exceeding 15 mm. However, as described throughout this specification, a desired installation includes a stabilizing infill layer (for example, sand) along with an appropriate shock-absorbing pad to achieve the desired turf performance.

[0022] In some embodiments, the woody strip corn infill material is compressed during production. Therefore, once incorporated into a turf system, the infill material will expand through irrigation to regain its original size / volume / shape. Through wetting, the woody strip corn infill material may swell (e.g., approximately 33% by volume) after water is applied. Due to this expansion, the initial free pile length may be approximately 25 to 30 mm before watering and expansion. It will be appreciated that the field may be watered naturally by rainfall, spray irrigation, use of a water truck, etc., in such a way that the woody strip corn infill material will swell to regain its original volume.

[0023] In other embodiments, to prevent the woody-corn-based fill material from sticking, the field may be treated with a brushing and loosening treatment. This brushing and loosening treatment may take place after a waiting period or immediately after applying water. Naturally, if there is no natural rainfall before the first use of the field, or if desired, the field may be sprayed either by an irrigation system, a water truck, or another suitable method. In some embodiments, a minimum amount of water, such as one (1) liter per square meter, should be applied. Ideally, four (4) liters per square meter, and no more than five (5) liters per square meter, should be used to fully expand the woody-corn-based fill material for optimal particle expansion.Once the original (or desired) volume has been reached, the field can be maintained as a regular field.

[0024] In some embodiments, woody strip corn-based filler material may have certain exemplary specifications for its use. For example, woody strip corn-based filler material may utilize a particle size distribution with an initial dry size of approximately 0.5 to 5 mm and a final size (e.g., original or expanded) of approximately 0.6 to 7 mm after wetting. In some embodiments, woody strip corn-based filler articles may include a reduction in dry bulk density of 20 to 90% after the first wetting and expansion at the site of use.

[0025] In other embodiments, the woody strip corn-based infill particles may include a reduction in bulk density of between 30% and 50%. In other embodiments, the woody strip corn-based infill particles may include a reduction in bulk density of 40%. Furthermore, as stated herein, the woody strip corn-based infill material may be used in combination with a stabilizing infill (e.g., sand) and a shock pad. By way of non-limiting example, this combination may achieve shock absorption of 55% to 70%, vertical deformation of 4 to 11 mm as measured by an Advanced Artificial Athlete (AAA), and a critical drop height greater than 1.3 meters, similar to a conventional third-generation infill artificial turf system.

[0026] In an example installation procedure for installing woody strip corn-based fill material with particle expansion, the amount of water and the rate of addition can vary based on the desired results. The method can control the expansion of the water-absorbing woody strip corn-based fill material by the amount and rate of water added to expand the woody strip corn-based fill.

[0027] An installation method may include spreading the woody strip corn-based fill material over a field, irrigating, brushing, loosening, and redistributing it. In one example, irrigation may involve a mass of water equal to twice the mass of dry-expanding woody strip corn-based fill material. Irrigation may involve applying the total mass of water using a spreader to distribute the water evenly across the field or surface. The woody strip corn-based fill material may be brushed and loosened between multiple water spreading stages.

[0028] Another installation method may involve a multi-stage process for installing the woody strip corn-based expansion fill material. A first layer of woody strip corn-based expansion fill material may be spread evenly across the field. In some embodiments, the mass of the first layer is 10 to 75% of the total amount of woody strip corn-based expansion fill material. In other embodiments, the mass may be 30% to 60% of the total amount. In yet another embodiment, the mass may be 33% of the total amount. After spreading the first layer on the field, the woody strip corn-based expansion fill material may be moistened.In some embodiments, the amount of water used to expand the woody-corn-based filler material ranges from 50% to 300% of the dry weight of the woody-corn-based filler material. In other embodiments, the amount of water can range from 175% to 225% of the dry weight. In yet another embodiment, the amount of water can be 200% of the dry weight of the woody-corn-based filler material. Although specific percentages, periods, and measurements are described herein, it should be noted that other aspects may exist that differ from those disclosed. As such, these additional aspects should be considered within the spirit and / or scope of this specification and the claims appended hereto.

[0029] The procedure may include a period in which water is spread over the woody strip corn-based fill material for a period of time of, for example, 2 hours. In some embodiments, the method may include a waiting period of more than 15 minutes after watering. In other embodiments, the waiting period may be more than 4 hours before any further action or step. The waiting period may be adjusted according to weather conditions, including the amount of sunlight, wind speed, temperature, and relative humidity.

[0030] As disclosed herein, the woody strip corn infill material may be brushed after watering. As required or desired, the woody strip corn infill material may be decompacted. In some embodiments, the woody strip corn infill material is preferably decompacted with almost any suitable decompactor that produces minimal damage to the woody strip corn infill material and the carpet. In some embodiments, a second or additional layer of dry-expanding woody strip corn infill material is spread over the first or previous layer. The second layer of infill may be expanded with water.

[0031] In some embodiments, the dry woody strip corn-based filler material can be hydrated and expanded using water or other liquids containing performance-modifying solutes that alter the absorption characteristics, surface properties, or other performance-related characteristics of the filler particles. Although much of the disclosure mentioned above uses traditional irrigation techniques for hydration and expansion, other liquids, such as those containing performance-modifying solutes, may be employed in conjunction with the woody strip corn-based filler. These alternative aspects should be included within the spirit and scope of the innovation and the claims appended hereto.

[0032] In one illustrative installation method, woody strip corn-based fill materials can be hydrated with water containing dissolved antifungal or antimicrobial compounds that provide these properties to the fill for slow release. Another example would be hydration with a colorant solution intended to provide a specific fill color, as desired, for aesthetic or functional purposes, such as UV resistance and enhanced durability.

[0033] Examples of preservatives that may be employed with the particles include, but are not limited to, Syzygium aromaticum extract oil, Cymbopogon genus extract oils, zinc salts such as zinc chloride, zinc pyrithione, zinc acetate, zinc sulfate; copper salts such as copper sulfate, copper chloride, copper acetate, copper nitrate, or copper nanoparticles; silver salts such as silver nitrate, silver chloride, silver microparticles or nanoparticles; chelating compounds such as citrate salts, 2,3-dimercaptopropanol, and ethylenediaminetetraacetate.

[0034] According to the principles of this disclosure, the embodiments relate to the use of woody strip corn-based particles as the primary infill for an artificial turf field. The infill, as shown in Figure 1, refers to a material that is deposited on the turf backing 120 and forms a layer 105 around the turf fibers 125. The infill is sandwiched between the turf fibers 125 that extend beyond the turf backing 120. The infill generally has a depth that covers a portion of the turf fiber (the unexposed portion of the turf fiber), leaving a portion of the turf fiber extending above the infill (the exposed portion of the turf fiber). Although a stabilizing infill and / or shock-absorbing pad is not shown in Figure 1, it can be appreciated that they may be employed in embodiments of the innovation as described above and below.

[0035] Infill 105 helps support the turf fibers 125 in an upright position and is used to provide traction and shock absorption. As described in detail above, in some embodiments, infill 105 comprises a specially designed layer of genetically modified woody strip corn-based particles. Infill 105 can be installed using a method of spreading the woody strip corn-based infill material over a field, watering, brushing, decompaction, and redistribution.

[0036] Furthermore, filler 105 may utilize a particle size distribution of woody strip corn-based filler with an initial dry size of 0.5 to 5 mm and a final size of 0.6 to 7 mm that expands after wetting. In some embodiments, the woody strip corn-based particles may include a reduction in dry bulk density of 20% to 90% after the first wetting and expansion at the site of use. In other embodiments, the woody strip corn-based particles may include a reduction in bulk density of between 30% and 50%. In another embodiment, the woody strip corn-based filler particles may include a reduction in bulk density of 40%. In other embodiments, the woody strip corn-based filling material can be used in combination with a shock pad to achieve desired shock absorption.For example, this combination of infill and shock pad can achieve shock absorption of 57% or more than a conventional infill artificial grass or carpet system.

[0037] In general, various types of fill arrangements are contemplated. For example, two-layer, three-layer, or other arrangements are considered. For convenience, this description mainly discusses two-layer and three-layer embodiments. The embodiments in this disclosure are intended to provide corn-based fill solutions. The materials discussed are primarily sand (as a stabilizing fill) and woody-strip corn-based fill material, but it should be understood that other materials may be included or substituted.

[0038] As described herein, according to certain embodiments of the innovation, the filler material has woody strip corn-based particles, which replace granulated rubber filler materials. As such, the filler is free of, or substantially free of, granulated rubber or similar materials. For example, in such embodiments, a layer of the filler (e.g., one of the multiple layers in the filler) may be made entirely (100% by weight), substantially (e.g., 65% or more or 75% or more by weight), mainly (e.g., 50% or more by weight), or predominantly (e.g., 45% or more by weight, or a weight percentage that is higher than the weight percentage of any other particle or sand in the same layer) of the woody strip corn-based particles.In some embodiments, the filler may be a single layer, and this single layer may be made entirely (100% by weight), substantially (e.g., 65% or more or 75% or more by weight), mainly (e.g., 50% or more by weight), or predominantly (e.g., 45% or more by weight, or a weight percentage that is greater than the weight percentage of any other particle or sand in the layer) of woody strip corn-based particles. It should be understood and appreciated that the woody strip corn-based particles can provide shock absorption and traction. The filler layer may include other organic materials or other materials in addition to or instead of those described herein.

[0039] The fill may include or comprise woody strip corn-based particles in a range of particle sizes for dry application and particle expansion after wetting. The size range may include a corn-based fill particle size distribution with an initial dry size of 0.5 to 5 mm and a final size of 0.6 to 7 mm after wetting. The woody strip corn-based particles may include a reduction in dry bulk density of 20% to 90% after the first wetting and expansion at the site of use, more preferably a reduction in bulk density of between 30% and 50%, or 40%. In some embodiments, the fill may comprise sand (e.g., in a layer) that is in a range of particle sizes. The sieve size range for sand can be between 20 and 50 (e.g., 0.841 mm-0.297 mm).

[0040] The fill may comprise the woody strip corn-based particles mentioned above and sand (as a stabilizing layer) in separate layers (one overlapping the other) or mixed together as shown in Figures 2 to 3, respectively. Figure 2 represents an illustrative fill 205 comprising woody strip corn-based particles and sand in separate layers. The first layer 210 (sequentially in the layer order from bottom to top, with the bottom layer being closest to the ground) is preferably a sand layer. In a second layer 215, the fill may comprise woody strip corn-based particles of a desired modified size and distribution. The second layer 215 may comprise the woody strip corn-based particles mentioned above, the fine sand mentioned above, or a combination thereof.When the second layer 215 includes both woody strip corn-based particles and sand, the woody strip corn-based particles and sand are preferably intermixed. Figure 3 represents an illustrative fill 305 comprising a layer 310 of intermixed woody strip corn-based particles and sand.

[0041] Although specific embodiments are shown and described herein, alternative embodiments employing alternative materials, mixtures, proportions, sizes, etc., are contemplated without departing from the spirit and / or scope of the innovation as described in detail. These alternative embodiments must be included within the spirit and scope of the innovation as described and claimed herein.

Claims

1. Artificial turf comprising: at least one layer of particles comprising woody strip corn-based particles that expand upon wetting; a stabilizing infill beneath the at least one layer of particles comprising woody strip corn-based particles; and a shock-absorbing pad beneath the stabilizing infill.

2. Artificial turf according to claim 1, wherein the stabilizing infill is sand.

3. Artificial turf according to claim 1, further comprising a second layer of particles comprising woody strip corn-based particles that expand upon wetting.

4. Artificial turf according to claim 1, wherein wetting uses water for hydration.

5. Artificial turf according to claim 1, wherein wetting uses a liquid comprising performance-modifying solutes. 6.Artificial turf according to claim 1, wherein the wetting process uses water containing antifungal or antimicrobial compounds.

7. Artificial turf according to claim 1, wherein the wetting process uses hydration with a colorant solution that provides a specific infill color.

8. Artificial turf according to claim 7, wherein the colorant solution provides desired aesthetic or functional purposes, such as UV resistance or increased durability.

9. Artificial turf according to claim 1, wherein the woody strip corn-based particles include a particle size distribution with an initial dry size of 0.5 to 5 mm and a final size of 0.6 to 7 mm after wetting. 10.Artificial turf according to claim 1, wherein the artificial turf achieves shock absorption of 55% to 70%, and vertical deformation of 4 to 11 mm as measured by an Advanced Artificial Athlete (AAA).

11. A method for installing an artificial turf field, comprising: spreading a layer of woody strip corn-based particles over a carpet that is on a stabilizing fill base, wherein the woody strip corn-based particle layer includes dry particles; moistening the woody strip corn-based particle layer so that the dry particles expand after moistening; brushing the woody strip corn-based particle layer; and decompacting the woody strip corn-based particle layer so that the woody strip corn-based particles are evenly distributed over the carpet. 12.

13. A method for installing an artificial turf field according to claim 11, wherein the woody strip corn-based particles are compacted before spreading.

14. A method for installing an artificial turf field according to claim 11, wherein the woody strip corn-based particles regain their original shape after wetting.

15. A method for installing an artificial turf field according to claim 11, wherein the wetting is carried out by rain, an irrigation system, or a water truck.

16. A method for installing an artificial turf field according to claim 11, wherein the wetting uses approximately four to five liters of liquid per square meter for particle expansion.A method for installing an artificial turf field according to claim 11, wherein the amount of liquid used to expand the woody-corn-based infill material corresponds to between 50% and 300% of the dry weight of the woody-corn-based particles.

17. A method for installing an artificial turf field according to claim 11, wherein the stabilizing infill base includes compacted stone or sand.

18. A method for installing an artificial turf field according to claim 11, further comprising spreading a second layer of woody-corn-based particles over the layer of woody-corn-based particles, wherein the second layer of woody-corn-based particles includes dry particles. 19.A method for installing an artificial turf field according to claim 11, wherein the wetting uses a liquid that includes a preservative, wherein the preservative is at least one of the following: Syzygium aromaticum extract oil, Cymbopogon extract oils, zinc salts such as zinc chloride, zinc pyrithione, zinc acetate, zinc sulfate; copper salts such as copper sulfate, copper chloride, copper acetate, copper nitrate, or copper nanoparticles; silver salts such as silver nitrate, silver chloride, or silver microparticles or nanoparticles; chelating compounds such as citrate salts, 2,3-dimercaptopropanol, and ethylenediaminetetraacetate. 20.Method of installing an artificial turf field according to claim 11, wherein the wetting uses a liquid that includes antifungal or antimicrobial compounds or a color dye solution that provides a specific color to improve resistance to ultraviolet rays or increase the durability of the artificial turf field.

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