ARTIFICIAL VEGETATION WITH ENGINEERED REFLECTANCE SPECTRA

An artificial turf system may comprise a plurality of synthetic filaments and a substrate base layer coupled to the plurality of synthetic filaments. Each filament of the plurality of synthetic filaments may comprise a pigment having an elevated solar reflectance for wavelengths less than 2500 nm. This elevated solar reflectance may be configured to reflect near-infrared radiation, thereby reducing near-surface air temperatures and the artificial turf surface temperatures. Such engineered pigments may also be advantageously used in the leaves of artificial vegetation systems, such as, for example, artificial shrubs and trees.

FIELD

This disclosure relates to artificial turf and vegetation products, specifically, artificial turf and vegetation engineered with pigments for the purpose of increasing the efficacy with which they reflect incident solar energy and emit their own thermal energy.

BACKGROUND

Elevated temperatures during the summer tend to increase the risk of heat-related morbidity and mortality, increase energy consumption, and increase water use. The impacts of extreme heat are particularly pronounced in urban environments, where water resources are limited and the urban heat-island effect can be severe. Use of vegetation is a common strategy to provide shading and/or evaporative cooling. Moreover, visual proximity to vegetation (e.g. real and/or artificial vegetation) has been shown to contribute to well-being and provide mental health benefits. However, natural vegetation such as trees can create significant problems in urban environments. They grow slowly, often taking nearly a decade from the date of planting before they are capable of providing significant shade. Trees also may interfere with below-ground and above-ground infrastructure and require significant maintenance and irrigation. Artificial alternatives for shade trees include artificial shade structures, which lack the aesthetic and mental health benefits of trees. Common alternatives for traditional grass include use of gravel/rock, decomposed/crushed granite, bare dirt, and artificial turf. However, these alternatives absorb and store heat, resulting in elevated surface and air temperatures, particularly in summer. Therefore, there is a need for artificial vegetation that mimics or improves upon properties of natural vegetation.

SUMMARY

A number of embodiments can comprise an artificial turf system. The artificial turf system can comprise a plurality of synthetic filaments, wherein each synthetic filament of the plurality of synthetic filaments can comprise a pigment having an elevated solar reflectance for wavelengths of less than 2500 nm, wherein the pigment is configured to reflect a majority of near-infrared radiation; and a substrate base layer coupled to the plurality of synthetic filaments.

Some embodiments can comprise a method of manufacturing artificial turf. The method can comprise forming a plurality of synthetic filaments; and coupling the plurality of synthetic filaments to a substrate base layer, wherein the forming further comprises: melting a plastic material; selecting an engineered pigment, wherein the engineered pigment is configured with a high solar reflectance (high spectral reflectance for wavelengths between 400 nm and 2500 nm); mixing the engineered pigment with the melted plastic material; and molding the melted plastic material using injection molding techniques.

DETAILED DESCRIPTION

The following description is of various exemplary embodiments only, and is not intended to limit the scope, applicability or configuration of the present disclosure in any way. Rather, the following description is intended to provide a convenient illustration for implementing various embodiments including the best mode. As will become apparent, various changes may be made in the function and arrangement of the elements described in these embodiments without departing from principled of the present disclosure.

For the sake of brevity, the connecting lines shown in various figures contained herein are intended to represent exemplary functional relationships and/or physical couplings between various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in artificial turf/vegetation products and methods of manufacturing thereof.

With reference toFIG.1, an artificial turf system100is shown in accordance with various embodiments. The artificial turf system100may comprise a plurality of synthetic filaments102coupled to a substrate base layer104. The plurality of synthetic filaments102may be individually coupled to the substrate base layer104, attached to the substrate base layer104in filament groups, either in uniform rows or in random groupings, or coupled to the substrate base layer104in any suitable configuration. In various embodiments, the plurality of synthetic filaments102may extend substantially orthogonal from the substrate base layer104. In various embodiments, the plurality of synthetic filaments102may be stitched to the substrate base layer104or attached using adhesives or fasteners. In various embodiments, the plurality of synthetic filaments102may be tufted into the substrate base layer104, adhered to the substrate base layer104, glued to the substrate base layer104, or otherwise fixed to the substrate base layer104by any method suitable for permanently fixing the plurality of synthetic filaments102to the substrate base layer104. Because manufactured synthetic turf is typically rolled up and transported for outdoor landscaping applications, it may be desirable to choose a method of adhering filaments to a base layer that prevents the filaments from fraying, or otherwise uprooting from the layer.

With further reference to the cross-section view of a portion of the artificial turf system100inFIG.2, and with continued reference toFIG.1, each filament in the plurality of filaments102may comprise a pigment105. In various embodiments, the pigment105may be configured with a high solar reflectance103for a significant portion of the solar spectrum having a wavelength of less than 2500 nm. Accordingly, the pigment105may be configured to reflect a high amount of near-infrared radiation.

The pigment105may include a single or multiple individual pigments and other additives intended to achieve various colors and brightness within the visible spectrum (e.g., browns and greens), while maintaining high overall solar reflectance. These pigments may be either organic or inorganic. Organic pigments include but are not limited to Copper phthalocyanines, Benzimidazolone, Chlorophyllin, Spirulina, other plant-based pigments, and the like. Inorganic pigments include but are not limited to Titanium dioxide, Barium sulfate, Mica, other mineral-based pigments, and the like.

FIG.6illustrates a graph600displaying a comparison of spectral reflectance for a plastic-resin infused with plant-based pigments (Pigment Sample), a commercially available sample of artificial turf (A-Turf), and a sample of natural lawn (Grass) in a working example of an embodiment. Each sample was tested for spectral reflectance in a spectrometer, sampling at wavelength steps of 5 nm. As can be seen inFIG.6, the overall solar reflectance of the Pigment, A-Turf, and Grass were 0.28, 0.11, and 0.30, respectively. While all samples have increased reflectance in the green part of the visible spectrum (500-550 nm), the natural grass and the plant-based pigment sample both have very high spectral reflectance in the near-infrared part of the spectrum (with increases in spectral reflectance shown in the 780-1350 nm range).

In contrast, the artificial turf maintains only about a 0.20 spectral reflectance throughout the near-infrared spectra. This demonstrates that a plastic sample with plant-based pigment can achieve nearly the same total solar reflectance as natural grass. Pigment mixtures, including the addition of lightening agents such as Titanium dioxide or Barium sulfate can enable artificial vegetation with higher solar reflectance than natural vegetation.

Returning now toFIG.1, increasing the solar reflectance of the plurality of synthetic filaments102is advantageous because less solar energy is absorbed (and more solar energy is reflected) by the synthetic filaments102. Generally speaking, surfaces that absorb more of the sun's energy are warmer to the touch than surfaces that reflect more of the sun's energy. Solar energy absorption is particularly acute for conventional artificial turf, which tends to be comprised of plastic and lacks the evapotranspiration and high near-infrared reflectance of natural grass. The pigment105increases the solar reflectance103of the plurality of synthetic filaments102, maintaining a cooler surface, reducing near-surface air temperatures and heat convection into the surrounding air. In various embodiments, the pigment105has a high solar reflectance particularly in the near-infrared spectrum (i.e., wavelengths from about 700 nm to about 2500 nm).

The pigment105may also reduce the need for irrigation. Conventional artificial turfs generally require less irrigation than natural turf. However, irrigation has been deployed onto conventional artificial turfs to combat elevated near-surface air temperatures. Increasing the solar reflectance103of the turf itself may reduce or eliminate the need for irrigation. Moreover, being spectrally-selective to primarily reflect near-infrared radiation, as opposed to visible light, the pigment105may enable the artificial turf100to remain cool, relative to conventional artificial turf, without affecting turf color. Accordingly, the pigment105may also enable greater turf design flexibility by enabling use of darker artificial turf colors, which may have otherwise been unsuitable for the heat of a given environment due to their increased absorption of solar energy. Incorporating the pigment105into the plurality of synthetic filaments102may also reduce color fading due to ultraviolet light exposure.

In various embodiments, the pigment105may also comprise a low thermal reflectance, or high thermal emittance, for example, in a wavelength greater than about 4000 nm. In various embodiments, the pigment105may comprise a thermal emittance in the longwave spectrum between 4,000 nm and 8,000 nm, 8,000 nm and 13,000 nm, 13,000 nm and 20,000 nm, 20,000 nm and 25,000 nm, or 25,000 nm and 30,000 nm. In many embodiments, a thermal emittance of a pigment may fall within the atmospheric infrared window (e.g., approx. 8,000 to 13,000 nm). In this way, thermal radiation emitted by the pigment remains largely unabsorbed and leaves the planet. Various embodiments of pigment105will include particularly high spectral emittance in this infrared window.

In various embodiments, the substrate base layer104may comprise at least one cavity configured to allow fluid to pass therethrough. Accordingly, the substrate base layer104may enable water from precipitation events to be transported to the substrate below the substrate base layer104. This may further increase cooling of the artificial turf system100and reduce air pollution associated with fine particles becoming airborne during moderate to high wind events. In various embodiments, the substrate base layer104may further comprise an acrylic-based polymer to enable greater water absorption. In various embodiments, the substrate base layer104may further comprise a heat storage system including high thermal mass and/or phase change materials. In various embodiments, the substrate base layer104may comprise a thermal storage system including high thermal mass materials and/or phase change materials to control the storage and subsequent release of heat.

In various embodiments, the plurality of filaments102may further comprise a lightening agent such as titanium dioxide (TiO2) and/or barium sulfate (BaSO4), which can both be highly reflective pigments. In various embodiments, the plurality of filaments102may comprise polyvinylidene fluoride (PVDF), a strong reflector of infrared radiation, or any suitable PVDF-based pigments. In various embodiments, each filament of the plurality of synthetic filaments102may be made of one or more of nylon, polypropylene, and polyethylene, or any other suitable synthetic material. In various embodiments, the substrate base layer104may be made of one or more of nylon, polyethylene, polypropylene, or combinations thereof, or any other suitable synthetic material. The substrate base layer104may be comprised of synthetic fibers that are thicker than the plurality of synthetic filaments102. The substrate base layer103may be a thick monofilament.

With reference toFIGS.3and4, an artificial vegetation system300is disclosed herein. In various embodiments, the artificial vegetation system300may comprise a plurality of synthetic leaves302and a base304coupled to the plurality of synthetic leaves302. In various embodiments, the artificial vegetation system300may further comprise a plurality of artificial stalks306, or stems. In various embodiments, each leaf of the plurality of synthetic leaves302may comprise a pigment305configured with a high level of solar reflectance303in a portion of the solar spectrum having wavelengths less than 2500 nm. In various embodiments, the pigment305may be configured to with a high degree of reflectance for near-infrared radiation. In various embodiments, the pigment305may be configured with a thermal emittance at a wavelength greater than 4000 nm. In various embodiments, each leaf of the plurality of synthetic leaves302. may be made of one or more of nylon, polypropylene, polyethylene, or the like. In various embodiments, each leaf of the plurality of synthetic leaves302may comprise polyvinylidene fluoride (PVDF). In various embodiments, each leaf of the plurality of synthetic leaves302may comprise titanium dioxide (TiO2).

Referring toFIG.5, a method of manufacturing500artificial turf is disclosed herein. In various embodiments, the method500may comprise forming (step502) a plurality of synthetic filaments. In various embodiments, the forming (step502) may further comprise melting (step503) a plastic material. In various embodiments, the melting (step503) may utilize a plastic material, wherein the plastic material is made of one or more of nylon, polypropylene, polyethylene, combinations thereof, or other suitable material.

In various embodiments, the forming (step502) may further comprise selecting (step504) an engineered pigment, wherein the pigment may be configured with a high level of solar reflectance for wavelengths less than 2500 nm. In various embodiments, the selecting (step504) may further comprise selecting an engineered pigment configured with a thermal emittance at a wavelength greater than 4000 nm. In various embodiments, the forming (step502) may further comprise mixing (step505) the pigment with the melted plastic. In various embodiments, the mixing (step505) may further comprise mixing the pigment with the melted plastic and polyvinylidene fluoride (PVDF). In various embodiments, the mixing (step505) may further comprise mixing the pigment with the melted plastic and titanium oxide (TiO2). In various embodiments, the forming (step502) may further comprise molding (step506) the plastic using injection molding techniques. In various embodiments, the selecting (step504) and mixing (step505) may occur before the molding (step506). In various embodiments, the method500of manufacturing artificial turf may further comprise coupling (step507) the plurality of synthetic filaments to a substrate base layer.

The present disclosure has been described with reference to various embodiments. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present disclosure. Accordingly, the specification is to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of the present disclosure. Likewise, benefits, other advantages, and solutions to problems have been described above with regard to various embodiments. However, benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or element.

As used herein, the terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Also, as used herein, the terms “coupled,” “coupling,” or any other variation thereof, are intended to cover a physical connection, an electrical connection, a magnetic connection, an optical connection, a communicative connection, a functional connection, and/or any other connection. When language similar to “at least one of A, B, or C” or “at least one of A, B, and C” is used in the specification or claims, the phrase is intended to mean any of the following: (1) at least one of A; (2) at least one of B; (3) at least one of C; (4) at least one of A and at least one of B; (5) at least one of B and at least one of C; (6) at least one of A and at least one of C; or (7) at least one of A, at least one of B, and at least one of C.