Filler for biodegradable artificial turf, comprising natural material having elastic function

Abstract

The present invention relates to a filler for a biodegradable artificial turf, the filler comprising a natural material having an elastic function. The filler is manufactured by using pellets obtained by mixing mineral materials such as loess and zeolite, a degradable vegetable material, and gelatin, and compression molding the mixture. The physical strength and elasticity of the filler can be improved, cracks in the filler caused by repeated use can be alleviated, and dust generation can be suppressed. In addition, the pellets are manufactured to include gelatin, which is a biodegradable material, instead of a polymer-based coating, and thus the loess, zeolite, and degradable vegetable material can be uniformly mixed and maintain the uniformly mixed state. Furthermore, since a polymer-based adhesive is not used, it is possible to prepare for recent environmental regulations regarding microplastics. Moreover, the loess and zeolite become exposed and emit far-infrared rays, thereby exhibiting antibacterial activity against fungi and harmful substances present between blades of the artificial turf, and thus can improve the durability of the artificial turf.

Description

Biodegradable artificial turf infill containing natural materials with elastic properties

[0001] The present invention relates to a biodegradable artificial turf filler comprising a natural material having elasticity.

[0002] Generally, many ball sports are played on grass fields. Grass fields typically use natural grass and artificial turf; notably, international hockey stadiums in Korea and around the world are 100% made of artificial turf. This artificial turf is a specialized landscaping material and serves as a substitute for grass that is artificially created to resemble the shape of grass.

[0003] Since its initial production in the United States, it has primarily been used in sports fields and can be utilized in areas where natural grass cannot grow, such as indoor gardens or outdoor areas facing north on high-rise buildings where sunlight is extremely limited. This artificial turf maintains a perpetual green color and is not restricted by environmental conditions, making it easy to maintain after installation. Furthermore, although the initial construction cost of an artificial turf field is higher than that of standard natural grass, it is highly preferred due to its semi-permanent lifespan, ease of maintenance, and a smooth surface suitable for exercise.

[0004] The above artificial turf field is completed by constructing a shock-absorbing artificial turf structure, laying silica sand or sand on the lower layer to protect the artificial turf, and then laying infill material to a certain height on top of it.

[0005] The aforementioned filler utilizes various elastic chips, primarily produced by crushing waste tires and industrial waste rubber, which have high specific gravity and good elasticity; however, this method presents issues such as environmental problems.

[0006] There is a need to develop an eco-friendly infill material that can prevent the occurrence of the aforementioned environmental problems and suppress the occurrence of cracks in the infill material due to usage frequency when used as an infill for artificial turf.

[0007] [Prior Art Literature]

[0008] [Patent Literature]

[0009] (Patent Document 1) KR 10-2652204 B1

[0010]

[0011] The object of the present invention is to a biodegradable artificial turf filler comprising a natural material having elasticity.

[0012] Another objective of the present invention is to provide a biodegradable artificial turf filler comprising natural materials that have elasticity functions capable of improving the physical strength and elasticity of the filler, mitigating cracking of the filler due to frequency of use, and suppressing dust, by mixing mineral materials such as loess, zeolite, biodegradable plant materials, and gelatin, and manufacturing the filler using compression-molded pellets.

[0013] Another objective of the present invention is to provide a biodegradable artificial turf filler comprising a natural material having elastic properties that can improve the durability of the artificial turf. This is achieved by including gelatin, a biodegradable material, when manufacturing pellets instead of a polymer-based coating, thereby ensuring that loess, zeolite, and biodegradable plant-based materials are uniformly mixed and maintained in a uniformly mixed state, and by eliminating the separate use of polymer-based adhesives, it can prepare for recent environmental regulations regarding microplastics. Furthermore, the loess and zeolite are exposed and emit far-infrared rays, which provide antibacterial action against mold and harmful substances embedded between the artificial turf fibers.

[0014]

[0015] To achieve the above-mentioned objective, the present invention relates to a naturally degradable artificial turf filler comprising a spherical molded chip in which loess, zeolite, a biodegradable plant material, and gelatin are uniformly mixed, wherein the biodegradable plant material comprises a natural material having elasticity selected from the group consisting of oak chips, cork, rice husks, and mixtures thereof.

[0016] In addition, the molded chip may have an average diameter of 1 mm to 10 mm.

[0017] In addition, the above loess may have an average particle diameter of 0.02 mm to 0.05 mm.

[0018] In addition, the zeolite may contain silicon and aluminum in a molar ratio of 1.0 : 1.0 to 1.5 : 1.0.

[0019] In addition, the molded chip may contain loess and zeolite in a weight ratio of 4.5:3 to 6.0:0.5.

[0020] In addition, the above-mentioned biodegradable plant material may include oak chips, cork, and rice husks in a weight ratio of 5.0 : 3.0 : 1.0.

[0021] In addition, the molded chip can be manufactured by mixing loess, zeolite, biodegradable plant material, and gelatin to prepare a composite mixture, melting it for 1 hour under temperature conditions of 60°C to 80°C, manufacturing it into pellets under pressure conditions of 100 MPa to 150 MPa, and grinding the upper and lower edges of the pellets to produce a spherical shape.

[0022] In addition, the gelatin is included by mixing with water, and the gelatin and water can be mixed in a weight ratio of 1.0 to 100.0.

[0023] In addition, the molded chip may further include cellulose.

[0024] In addition, the molded chip may further include one selected from the group consisting of bentonite, ball clay, kaolin, and mixtures thereof.

[0025]

[0026] The present invention manufactures a filler by mixing mineral materials such as loess, zeolite, biodegradable plant material, and gelatin, and using compression-molded pellets thereof, thereby improving the physical strength and elasticity of the filler, mitigating cracking of the filler due to frequency of use, and suppressing dust.

[0027] Furthermore, by including gelatin, a biodegradable material, in the pellets instead of a polymer-based coating, the loess, zeolite, and degradable plant-based materials are uniformly mixed and maintained. Additionally, by eliminating the need for separate polymer-based adhesives, it is possible to prepare for recent environmental regulations regarding microplastics. Moreover, the exposed loess and zeolite emit far-infrared rays, providing antibacterial action against mold and harmful substances embedded within the artificial turf, thereby improving the durability of the artificial turf.

[0028] In addition, the filler material in the present invention is capable of absorbing moisture, so it can release stored moisture during the summer to maintain the artificial turf sports field environment in an optimal state in high-temperature environments, thereby allowing users to use it safely without being exposed to the risk of burns.

[0029] In addition, conventional natural chips made of simple materials had a low specific gravity, resulting in a high loss rate during the rainy season; however, compounding with minerals increases the weight, which has the effect of reducing the loss rate.

[0030]

[0031] Figure 1 is a schematic diagram of a process for manufacturing an artificial turf filler according to the present invention.

[0032]

[0033] The present specification will be described in more detail below.

[0034]

[0035] The present invention relates to a biodegradable, eco-friendly material that combines enhanced physical strength and elasticity for artificial turf infill. More specifically, the structure of artificial turf may include a base layer (aggregate layer), silica sand, infill, and an artificial turf mat based on the bottom portion. All components are installed and undergo physical deformation depending on user frequency and environment. There is a high possibility that harmful substances, such as mold, may exist due to microorganisms resulting from wear of the infill and moisture absorption between the artificial turf fibers. However, in the case of existing infill materials, synthetic resins and rubber are used, which become fine powder over time, raising concerns about environmental pollution and adverse effects on user health.

[0036] In other words, when synthetic resins and rubber are used as infill for artificial turf, they gradually pulverize due to impact during use. Consequently, as microplastics leak out, they cause environmental pollution and can also enter the human body through the user's respiratory system.

[0037] It can be said that the development of infill materials for artificial turf is necessary to resolve these problems.

[0038] Accordingly, the present invention relates to an infill material for artificial turf, wherein the physical strength and elasticity of the infill material are improved by compounding mineral materials such as loess, zeolite, and biodegradable plant materials. Furthermore, by including eco-friendly gelatin, the bonding strength between the loess, zeolite, and biodegradable plant materials is enhanced when molded into pellets, and elasticity is maintained, thereby mitigating cracking of the infill material due to frequency of use. Additionally, by using eco-friendly gelatin, there is an effect of suppressing dust that may be generated by pressure applied to the infill material.

[0039] In addition, by using biodegradable materials instead of polymer-based coatings, it can be considered an eco-friendly filler capable of overcoming recent environmental regulations regarding microplastics.

[0040] Furthermore, instead of coating the entire outer surface of the filler, the filler is manufactured by mixing gelatin and compression molding, thereby exposing the loess and zeolite to the outside. This allows far-infrared rays generated by the loess and zeolite to be emitted outward, which enables an antibacterial action against mold and harmful substances embedded between the artificial turf fibers. Through such antibacterial action, mold and harmful substances can be suppressed, thereby improving user health and the durability of the artificial turf.

[0041] More specifically, the biodegradable artificial turf filler containing a natural material having elasticity according to the present invention is a molded chip comprising loess, zeolite, biodegradable plant material, and gelatin, and the biodegradable plant material may be selected from the group consisting of oak chips, cork, rice husk, and mixtures thereof.

[0042] The above-mentioned molded chips may have an average diameter of 1 mm to 10 mm. In order to be used as an infill material for artificial turf, the above-mentioned molded chips must be spherical in shape with a suitable size, and the average diameter suitable for use as an infill material for artificial turf is 1 mm to 10 mm.

[0043] The above loess has an average particle diameter of 0.02 mm to 0.05 mm, and the above zeolite may contain silicon and aluminum in a molar ratio of 1.0 : 1.0 to 1.5 : 1.0. Additionally, the above molded chip may contain loess and zeolite in a weight fraction of 4.5 : 3 to 6.0 : 0.5, in a weight fraction of 4.5 : 3 to 6.0 : 1.0, or in a weight fraction of 4.5 : 1.0. That is, the above molded chip may contain loess and zeolite, or may be composed solely of loess. The above loess and zeolite are included to improve the strength of the filler. By mixing loess particles with a suitable average diameter and zeolite in the above weight ratio, damage that may occur due to external impact can be minimized to prevent fine powdering, and furthermore, through the effect of far-infrared radiation generated by the loess, an antibacterial function can be exhibited.

[0044] The above-mentioned biodegradable plant material may include oak chips, cork, and rice husks in a weight ratio of 5.0:3.0:1.0. When the above-mentioned biodegradable plant material is mixed with the loess and zeolite mentioned above, it can not only enhance physical strength and provide elasticity when used as a filler for artificial turf, but also prevent environmental pollution problems by allowing it to naturally decompose due to the use of eco-friendly materials.

[0045] That is, the above-mentioned loess is not included in the form of clay mixed with water, but is included as loess particles and in the form of zeolite particles. When the loess and zeolite are mixed, fine pores may occur, and if such pores are included, when used as a filler, the shock absorption effect due to external pressure is reduced, and a problem may arise where it breaks easily. To prevent this problem, the present invention includes oak chips, cork, and rice husks as biodegradable plant materials, thereby primarily preventing the formation of pores when mixed with loess and zeolite, and secondarily, by mixing in gelatin, the formation of pores can be prevented and elasticity can be strengthened.

[0046] The above gelatin is mixed with water in a weight ratio of 1.0:100.0 and may be included at 5% relative to the total weight of the loess and zeolite as described below. When using gelatin mixed with water within the above range, not only can the bonding strength of the loess, zeolite, and biodegradable plant material be further enhanced, but external shocks can also be absorbed, and even if the molded chip is damaged by a stronger impact, the fine powdering of the molded chip can be prevented.

[0047] The gelatin mentioned above can not only prevent the loess, zeolite, and biodegradable plant material, which are components of the aforementioned molded chip, from decomposing due to external impact when used as infill for artificial turf, but also prevent cracking caused by external impact and, even if powdering occurs, prevent leakage to the outside. In other words, since the gelatin is uniformly mixed and included with the loess, zeolite, and biodegradable plant material during the manufacturing process of the molded chip, the adhesive effect of the gelatin throughout the molded chip prevents decomposition, cracking, and powdering caused by external impact.

[0048] In the case of gelatin-free fillers, fine powder can detach from the surface due to collisions between fillers or external forces, allowing this fine powder to easily migrate outward. In other words, while external impact may cause cracks or damage to the filler, fine powder can detach from the surface even from minor impacts prior to the occurrence of such cracks or damage.

[0049] As mentioned above, such fine powders can not only cause environmental pollution problems but also cause health issues within the human body.

[0050] Accordingly, in the present invention, by uniformly including gelatin, decomposition, cracking, and powdering caused by external impact can be prevented through the adhesive effect.

[0051] As described above, the biodegradable artificial turf filler of the present invention is a molded chip comprising loess, zeolite, biodegradable plant material, and gelatin, and may additionally include cellulose in addition to the gelatin. The cellulose may be included by mixing it in the same weight ratio with water as the gelatin. When the cellulose is included together with gelatin, it may be included in the same weight ratio as the gelatin, and the gelatin and cellulose may be included at 5% relative to the total weight of the loess and zeolite. Excellent adhesive effect can be achieved within the above numerical range; if included below the above range, the adhesive effect is low and may easily decompose or crack due to external impact, and if exceeded the above range, the gelatin and cellulose are included in excess, which may reduce the elastic effect for use as a filler.

[0052] As described above, when cellulose is additionally included, the adhesive effect can be enhanced compared to when gelatin is used alone, thereby further increasing the effect of preventing decomposition, cracking, and powdering caused by external impact.

[0053] Additionally, the molding chip of the present invention may further include a component selected from the group consisting of bentonite, ball clay, kaolin, and mixtures thereof. As the above components are included in the molding chip, the elastic function can be further enhanced.

[0054] The artificial turf infill material of the present invention can exhibit excellent physical strength and elasticity, making it suitable for use as a replacement for existing infill materials. Furthermore, unlike conventional polymer-based infill materials, it prevents fine powdering and is composed solely of biodegradable components, allowing for simple disposal even after the artificial turf is removed, and does not cause environmental pollution upon disposal.

[0055] The above-mentioned molded chip may be prepared by mixing loess, zeolite, biodegradable plant material, and gelatin to produce a composite mixture, melting it for 1 hour under temperature conditions of 60°C to 80°C, producing it into a pellet under pressure conditions of 100 MPa to 150 MPa, and grinding the upper and lower edges of the pellet to produce a spherical shape.

[0056] To manufacture the above-mentioned spherical chips, they are compression-molded into pellets. After manufacturing the pellets, gelatin is incorporated to create a composite mixture to enhance the adhesion of loess, zeolite, and biodegradable plant materials. Subsequently, through a drying process, the included water is removed to facilitate the mixing of gelatin, and the pellets are then manufactured through compression molding. By compression molding for 3 hours under the aforementioned pressure conditions, solid pellets without voids can be produced. These pellets possess elastic properties and can be used as infill for artificial turf. Since the pellets are not naturally spherical, the top and bottom edges are ground to form them into a spherical shape. While grinding to a spherical shape can be performed using a barrel process, the above process is not limited to the barrel process; any method capable of producing spherical infill can be utilized without restriction.

[0057]

[0058] Hereinafter, embodiments of the present invention are described in detail so that those skilled in the art can easily implement the invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0059]

[0060] Preparation Example 1

[0061] Manufacture of biodegradable artificial turf filler containing natural materials with elastic properties

[0062] Figure 1 is a schematic diagram of a process for manufacturing an artificial turf filler according to the present invention.

[0063] As shown in Figure 1 above, loess and zeolite were prepared in a weight ratio of 4.5:1. A gelatin solution was prepared by mixing gelatin and distilled water in a weight ratio of 1.0:100.0, comprising 5% of the total weight of the loess and zeolite. Additionally, oak chips, cork, and rice husks were mixed in a weight ratio of 5.0:3.0:1.0 and prepared at 10% to 15% of the total weight of the loess and zeolite. This mixture was then combined with the loess, zeolite, and gelatin solution to produce a composite composition. The composite composition was dissolved at a temperature of 60°C to 80°C for 1 hour. Subsequently, it was formed into pellets by applying a molding pressure of 100 MPa to 150 MPa. Finally, the upper and lower edges of the pellets were ground through a barrel process to produce spherical fillers.

[0064] The above loess used had an average particle diameter of 0.02 mm to 0.05 mm, and the zeolite used had an average particle diameter of 0.1 mm to 0.3 mm and a molar ratio of silicon to aluminum of 1.0:1.0.

[0065]

[0066] Preparation Example 2

[0067] A filler was prepared in the same manner as in Preparation Example 1, except that the molar ratio of silicon to aluminum in the zeolite was 1.5:1.0.

[0068]

[0069] Preparation Example 3

[0070] A filler was prepared in the same manner as in Preparation Example 1, except that it did not contain zeolite and only loess was used.

[0071]

[0072] Preparation Example 4

[0073] The filler was prepared in the same manner as in Preparation Example 1, except that it did not contain a gelatin solution.

[0074]

[0075] Preparation Example 5

[0076] A filler was prepared in the same manner as in Preparation Example 1, except that the moisture was not removed by dissolving at a temperature of 60°C to 80°C for 1 hour.

[0077]

[0078] Experimental Example 1

[0079] Review of filler shape according to manufacturing process

[0080] For the pellets prepared according to the methods of Preparation Examples 1 and 5, it was checked whether cracks occurred. More specifically, after preparing the pellets according to Preparation Examples 1 and 5, the occurrence of cracks was checked visually. The experimental results are as shown in Table 1 below:

[0081] Preparation Example 1 Preparation Example 5 Crack count XO

[0082] According to the above experimental results, it was confirmed that in the case of Manufacturing Example 5, which did not undergo a process to remove moisture, most of the pellets cracked or broke completely during the compression molding process.

[0083] In other words, if moisture is not sufficiently removed during the manufacturing process, there will be a problem of cracking when molded into pellets, making it impossible to manufacture as a filler.

[0084]

[0085] Experimental Example 2

[0086] Evaluation of physical properties of filler

[0087] For the fillers prepared according to Manufacturing Examples 1 to 4 above, tensile strength, wear resistance, and compression recovery rate were evaluated.

[0088] The measurement method is specifically as follows:

[0089] tensile strength

[0090] Tensile strength was measured using a tensile testing machine in accordance with ASTM D638.

[0091] Compression recovery

[0092] A compression tester was used in accordance with ASTM D575. The fillers of Preparation Examples 1 to 4 were placed in a square flask to a height of 10 cm, and a load of 0.5 MPa was applied for 1 minute, followed by a recovery time of 30 seconds, as one cycle. After repeating this for 100 cycles, the degree of compression was evaluated. The compression recovery force was measured by determining the degree of compression relative to the original height.

[0093] The measurement results are as shown in Table 2 below:

[0094] Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Tensile Strength (MPa) 53542312 Compressive Recovery (%) 99997624

[0095] According to the experimental results above, it was confirmed that Preparation Examples 1 and 2 exhibited excellent tensile strength and compressive recovery. On the other hand, while Preparation Example 3 showed excellent compressive recovery, its tensile strength was comparable to that of conventional fillers, but it exhibited lower values ​​compared to Preparation Examples 1 and 2. Preparation Example 4 showed low values ​​for both tensile strength and compressive recovery.

[0096]

[0097] Experimental Example 3

[0098] Antimicrobial test

[0099] An antibacterial test was conducted on the filler prepared according to Preparation Example 1 and Preparation Example 2 above. For the antibacterial test, the test strain was inoculated into 100 mL of distilled water in which 4 g of the sample was dissolved, and the bacterial reduction rate was measured after 24 hours of incubation. The details of the antibacterial test were carried out according to KCL-FIR-1002 (2011 "Shaking flask method").

[0100] The test was conducted under temperature conditions of 37.0±0.2℃, and Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 15442 were used as fungal strains.

[0101] As a result of evaluating the reduction rate of mold strains after 24 hours, it was confirmed that the antibacterial effect was high, with bacterial reduction rates of over 72% and over 73%, respectively. Accordingly, it was confirmed that when used as an infill material for artificial turf, bacterial proliferation can be sufficiently inhibited due to its antibacterial properties.

[0102]

[0103] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

Claims

1. It is a spherical molded chip uniformly mixed with loess, zeolite, biodegradable plant material, and gelatin, and The above-mentioned biodegradable plant material is a biodegradable artificial turf filler comprising a natural material having elasticity selected from the group consisting of oak chips, cork, rice husks, and mixtures thereof.

2. In Paragraph 1, The above-mentioned molded chips are biodegradable artificial turf fillers comprising natural materials having elasticity and having an average diameter of 1 mm to 10 mm.

3. In Paragraph 1, The above loess is a biodegradable artificial turf filler containing a natural material having elasticity with an average particle diameter of 0.02 mm to 0.05 mm.

4. In Paragraph 1, The above zeolite is a biodegradable artificial turf filler comprising a natural material having elasticity, comprising silicon and aluminum in a molar ratio of 1.0:1.0 to 1.5:1.

0.

5. In Paragraph 1, The above-mentioned molded chip is a biodegradable artificial turf filler containing a natural material having elasticity, comprising loess and zeolite in a weight fraction of 4.5:3 to 6.0:0.

5.

6. In Paragraph 1, The above-mentioned biodegradable plant material is a naturally biodegradable artificial turf filler comprising natural materials having elasticity, including oak chips, cork, and rice husks in a weight fraction of 5.0:3.0:1.

0.

7. In Paragraph 1, The above-mentioned molded chip is a biodegradable artificial turf filler containing a natural material having elasticity, prepared by mixing loess, zeolite, biodegradable plant material, and gelatin to prepare a composite mixture, melting it for 1 hour under temperature conditions of 60°C to 80°C, manufacturing it into pellets under pressure conditions of 100 MPa to 150 MPa, and grinding the upper and lower edges of the pellets to produce a spherical shape.

8. In Paragraph 7, The above gelatin is included by mixing with water, and A biodegradable artificial turf filler comprising a natural material having elasticity, wherein the above gelatin and water are mixed in a weight fraction of 1.0 : 100.

0.

9. In Paragraph 1, The above-mentioned molded chip is a biodegradable artificial turf filler containing a natural material having elasticity functions, further including cellulose.

10. In Paragraph 1, The above-mentioned molded chips are a biodegradable artificial turf filler comprising a natural material having elasticity, further comprising a material selected from the group consisting of bentonite, ball clay, kaolin, and mixtures thereof.

11. Artificial turf using the filler of Paragraph 1.

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