A GRANULAR INFILL MATERIAL AND A PROCESS FOR PRODUCING THE GRANULAR INFILL MATERIAL

Abstract

A disclosed process for producing granular infill material for a synthetic turf surface includes providing scraps of a composite material comprising a textile support. A coating of the textile support includes a polymeric material. A weight percentage of the textile support is greater than or equal to 5% of a total weight of the composite material. The production process includes grinding the scraps to obtain scrap pieces, preparing a mixture comprising the scrap pieces, and heating the mixture to obtain a blend comprising the polymeric material in a softened state and pieces of the textile support dispersed in the polymeric matrix. A plurality of solid granules may be obtained from the blend to make the granular infill material. Each granule includes a polymeric matrix including the polymeric materials and a reinforcing filler dispersed in the polymeric matrix. The reinforcing filler may include pieces of the textile support.

Claims

1-10. (canceled)

11. A process for producing a granular infill material for a synthetic turf surface, the process comprising: providing scraps of a composite material comprising a textile support and a coating of the textile support, wherein the coating comprises a polymeric material and wherein a weight percentage of the textile support is at least 5% of a total weight of the composite material; grinding the scraps to obtain scrap pieces; preparing a mixture comprising the scrap pieces; heating the mixture to obtain a blend comprising: the polymeric material in softened state; and pieces of the textile support dispersed in the polymeric material; obtaining, from the blend, a plurality of granules for the granular infill material, wherein each of the granules comprises: a polymeric matrix, wherein the polymeric matrix includes the polymeric material; and a reinforcing filler dispersed in the polymeric matrix, the reinforcing filler comprising the pieces of the textile support.

12. The process of claim 11, wherein providing scraps of the composite material comprises providing scraps of imitation leather.

13. The process of claim 12, wherein providing scraps of imitation leather comprises providing scraps of two or more imitation leather materials.

14. The process of claim 13, wherein a weight percentage of the textile support is in a range between 8% and 40% for each of the two or more imitation leather materials.

15. The process of claim 13, wherein a weight percentage of the polymeric material is greater than or equal to 50% for each of the two or more composite materials comprises.

16. The process of claim 11, wherein the polymeric material is selected from: polyvinylchloride, polyurethane, polyester, polypropylene, or mixtures thereof.

17. The process of claim 16, wherein the textile support includes at least one of: natural textile fibers and synthetic textile fibers.

18. The process of claim 17, wherein a fabric type of the textile support is selected from: knitted fabric, warp and weft fabric and non-woven fabric.

19. The process of claim 11, wherein preparing the mixture comprises adding to the scrap pieces a further polymeric material not coming from the scraps, and wherein the further polymeric material is selected from: polyvinylchloride, polyurethane, polyester, polypropylene.

20. The process of claim 11, wherein preparing the mixture comprises: adding to the scrap pieces an amount of a reinforcing material not coming from the scrap pieces, wherein the reinforcing material is a mineral material comprising a least one of: calcium carbonate, talc, kaolin, sand, and lime.

21. The process of claim 20, wherein the reinforcing material includes at least one plant material selected from: coco fiber/peat, cork, rice husk, banana fiber/peat, lignin, cellulose, tree defibration, and hemp.

22. The process of claim 21, wherein preparing the mixture further includes: adding to the scrap pieces at least one additive selected from: flame retardants, antioxidants, anti-UV rays and dyes.

23. The process of claim 11, wherein preparing the mixture comprises: adding to the scrap pieces an amount of wallpaper scrap pieces, wherein the amount of wallpaper scrap pieces is less than or equal to 55% of a mass of the scrap pieces.

24. The process of claim 11, further comprising: feeding the mixture to an extruding device.

25. The process of claim 24, wherein heating the mixture comprises bringing the blend to a temperature greater than or equal to a melting temperature of the polymeric material and less than or equal to a melting temperature of a material of the textile support.

26. The process of claim 24, wherein heating the mixture comprises bringing the blend to a temperature greater than or equal to 130° C. and less than or equal to 220° C.

27. The process of claim 24, wherein obtaining the granules comprises: extruding a plurality of sizes of the blend; and grinding the sizes of blend.

28. A granular infill material for a synthetic turf surface, wherein the granular infill material comprises: a plurality of granules, wherein each of the plurality of granules includes: a polymeric matrix comprising a polymeric material; and a reinforcing filler dispersed in the polymeric matrix, the reinforcing filler comprising pieces of a textile support.

29. The granular infill material of claim 28, wherein the polymeric matrix and the reinforcing filler at least partially derive from scraps of a composite material comprising: the pieces of the textile support; and a coating of the textile support, wherein the coating comprises the polymeric material, and wherein a weight percentage of the textile support is greater than or equal to 5% of a total weight of the composite material.

30. The granular infill material of claim 29, wherein: the polymeric matrix comprises an amount of a further polymeric material not coming from the scraps, wherein the further polymeric material is selected from: polyvinylchloride, polyurethane, polyester and polypropylene; the reinforcing filler comprises a network of textile fibers originated from pieces of textile support and an amount of a reinforcing material not coming from the scraps, wherein the reinforcing material is a mineral material selected from: calcium carbonate, talc, kaolin, sand, and lime.

31. The granular infill material of claim 30, wherein: the reinforcing filler further includes a plant material selected from: coco fiber/peat, cork, rice husk, banana fiber/peat, lignin, cellulose, tree defibration, and hemp; and each of the granules comprises a respective plurality of textile fibers which protrude from an outer surface of the granules.

32. A synthetic turf surface comprising: a synthetic turf mat; and a layer of a granular infill material according to claim 28 arranged above the synthetic turf mat.

33. The synthetic turf surface of claim 32, wherein a mass per unit area of the layer of granular infill material is in a range between 3 kg/m.sup.2 and 20 kg/m.sup.2.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] FIG. 1 schematically shows in vertical section a synthetic turf surface comprising a layer of granular infill material according to the present invention;

[0049] FIG. 2 shows a block diagram of a production process of a granular infill material according to the present invention.

DETAILED DESCRIPTION OF SOME EMBODIMENTS OF THE INVENTION

[0050] The features and the advantages of the present invention will be further clarified by the following detailed description of some embodiments, presented by way of non-limiting example of the present invention, with reference to the attached figures.

[0051] With reference to FIG. 1, it is schematically shown a synthetic turf surface 400 comprising a compact clay substrate 401 (for example as known), on which a synthetic turf mat 100 is laid, not further described as, for example, of known type, and at least one layer of granular infill material 402 (comprising a plurality of granules 200) arranged on the synthetic turf mat 100 between the artificial fibres 404 of the mat 100 (which simulate the grass thread). Exemplarily the layer of granular infill material 402 has a mass per unit area equal to about 8 kg/m.sup.2. In some embodiments, two or more superimposed layers of granular material of different composition are provided. Typically, the granular material of the present invention is a performance infill and therefore is arranged at the top of the infill.

[0052] The synthetic turf surface 400 is not further described and illustrated as known per se.

[0053] Preferably each granule 200 comprises a polymeric matrix comprising a polymeric material and a reinforcing filler dispersed in the polymeric matrix comprising pieces of a textile support, with at least part of the polymeric matrix and the reinforcing filler deriving from scraps of at least one composite material which comprises the textile support and a coating of the textile support in the polymeric material, wherein a weight percentage of the textile support is greater than or equal to 5%.

[0054] Exemplarily these composite materials are imitation leather wherein the coating of the textile support is made by spreading the textile support with the polymeric material. With reference to FIG. 2, the reference number 20 schematically indicates a container for collecting scraps 1 of the composite materials, for example scraps of imitation leather. After collection, the process comprises grinding the scraps to obtain scraps pieces 2. The grinding is exemplarily carried out by feeding such scraps 1 to one or more grinding mills 21 (only schematically shown) in which for example there is a respective blades/counter-blades system (for example of known type). For example, the grinding can comprise a coarse pre-grinding of the scraps 1 and a subsequent micronation for obtaining scraps pieces 2 having spatial dimensions of about 0.1 mm. The grinding operation of the scraps 1 is not further described as for example of known type.

[0055] At this point, the process comprises preparing a mixture 3 comprising the scraps pieces 2. Exemplarily the preparation of the mixture 3 is carried out inside special mixing devices 22 (only schematically shown and for example of known type) in which the ground scraps pieces 2 are conveyed.

[0056] In one embodiment, the preparation of the mixture 3 comprises adding to the scrap pieces 2 an amount, exemplarily in granular form, of a further polymeric material not coming from the scraps 1. This further polymeric material can be new raw material or come from the grinding of articles scraps made of the further polymeric material and devoid of textile support, such as scraps of imitation leather from the automotive sector. In the latter case, these articles scraps can alternatively be directly collected (e.g., in the container 20) and/or ground (e.g., in the grinding mill 21) together with the scraps 1 of composite material.

[0057] In one embodiment the preparation of the mixture 3 comprises adding to the scrap pieces 2 an amount of wallpaper scraps (typically comprising paper and PVC), for example directly collected (e.g., in the container 20), and/or ground (e.g., in the grinding mill 21), together with the scraps 1 of composite material.

[0058] In one embodiment, the preparation of the mixture 3 comprises adding to the scrap pieces 2 an amount of a reinforcing material not coming from the scraps 1.

[0059] Advantageously, the choice of the possible combination of heterogeneous composite materials in the initial scraps 1, and/or of the type and amount of further polymeric material, of the reinforcing material and/or of the wallpaper is made case by case according to the starting materials and to the final composition of the granule 200 to be obtained. Typically, in the granule 200, the part of polymeric matrix is globally equal to 60-70% of the total weight, the rest being substantially reinforcing filler (except for the additives and any impurities).

[0060] In one embodiment the preparation of the mixture 3 comprises adding to the scrap pieces 2 flame retardant additives, anti-oxidant additives, anti-UV ray additives and/or dye additives.

[0061] Once the preparation of the mixture 3 has been completed inside the mixing device 22, the latter acts as a tank for feeding the mixture 3 to an extruder 30 (only schematically shown and for example of known type).

[0062] For example, the mixing device 22 comprises a stirring and feeding device 23 (only schematically shown) which carries out a forced mixing of the mixture 3 and the feeding of a predetermined amount of mixture 3 inside the extruder 30.

[0063] Following the feeding of the mixture 3 into the extruder 30, the process comprises heating the mixture 3, exemplarily to a temperature equal to about 180° C., for obtaining a blend comprising the polymeric material (coming from the scraps 1, with possibly also the added polymeric material, such as the further polymeric material or the one coming from the wallpaper) in a softened state and pieces of the textile support (coming from the scraps 1, with possibly also the paper pieces coming from the wallpaper or the reinforcing material) dispersed in the polymeric material. Exemplarily the heating temperature is less than or equal to the melting temperature of the material of the textile support, for making a network of textile fibres, for example in straws form, originating from the textile support. Exemplarily the extruder 30 comprises a series of heating elements (of known type, not shown) and an extrusion screw (not shown and also of known type) suitable for allowing the movement and homogenization of the blend inside the extruder 30.

[0064] Exemplarily the mixture 3 fed into the extruder 30 enters, by rotation of the extrusion screw, in a compression area wherein the blend is formed, with the polymeric material that softens when subjected to strong pressures and heat application.

[0065] Subsequently, the blend is moved towards the extrusion/outlet head of the extruder 30 for being extruded.

[0066] Exemplarily the blend is extruded in the form of sizes 4, and for example these sizes 4 (typically in fluid form) undergo a first fragmentation by a cutting blade 31 (schematically shown and for example of known type).

[0067] Exemplarily the fragmented sizes 5 are subsequently fed to a transport screw 32 (schematically shown and for example of known type) in which, for example, a second fragmentation of the fragmented sizes 5 takes place.

[0068] Exemplarily the transport screw 32 then feeds the sizes pieces 6 (formed after the second fragmentation) to a grinding device 33, for example a grinding mill as those above-described, in which the grinding of the sizes pieces 6 exemplarily takes place for obtaining the granules 200 (exemplarily each one comprising a respective plurality of textile fibres which protrude from an outer surface of the granule).

[0069] Optionally, the granules 200 thus obtained can be subsequently fed into a sieving device (for example a vibrating screen with superimposed sieves in which there are a plurality of openings having different dimensions) which allows the removal of possible cutting powders and/or the subdivision of the granules 200 according to the granulometry. The average size of the granules ranges from about 2 mm to 5 mm.

[0070] In the following some examples of production processes of the granules 200 according to the present invention are described.

Example 1

[0071] Composition of the scraps 1 of composite material: imitation leather (single type) with textile support 20% and polymeric material 80%; [0072] Type and material of the textile support, knitted fabric made of polyester (PET) and cotton; [0073] Polymeric material: polyvinylchloride (PVC); [0074] Further polymeric material: absent; [0075] Wallpaper scraps: absent; [0076] Reinforcing material: calcium carbonate; [0077] Additives: anti UV rays, flame retardants and dyes.

Example 2

[0078] Composition of the scraps 1 of composite material: imitation leather (single type) with textile support 30% and polymeric material 70%; [0079] Type and material of the textile support: knitted fabric made of cotton; [0080] Polymeric material: polyvinylchloride (PVC); [0081] Further polymeric material: polyvinylchloride (PVC); [0082] Wallpaper scraps, absent; [0083] Reinforcing material: calcium carbonate; [0084] Additives: anti UV rays, flame retardants and dyes.

Example 3

[0085] Composition of the scraps 1 of composite material: imitation leather (heterogeneous): [0086] 33% first sub-group: textile support 10% and polymeric material 90%, [0087] 33% second sub-group: textile support 25% and polymeric material 75%, [0088] 33% third sub-group: textile support 35% and polymeric material 65%; [0089] Type and material of the textile support: [0090] first sub-group: knitted fabric made of polyamide, [0091] second sub-group: knitted fabric made of polyester, [0092] third sub-group: knitted fabric made of cotton; [0093] Polymeric material: [0094] first and second sub-group: polyvinylchloride (PVC), [0095] third sub-group: polyurethane (PU); [0096] Further polymeric material: combination of polyvinylchloride (70%) and polyurethane (30%); [0097] Wallpaper: absent; [0098] Reinforcing material: calcium carbonate; [0099] Additives: anti UV rays, flame retardants and dyes.

Example 4

[0100] Composition of the scraps 1 of composite material: imitation leather (single type) with textile support 25% and polymeric material 75%; [0101] Type and material of the textile support: knitted fabric made of polyester (PET) and cotton; [0102] Polymeric material: polyurethane (PU); [0103] Further polymeric material: recycled polyurethane; [0104] Wallpaper: weight content equal to about 20% of the total weight of the scraps 1; [0105] Reinforcing material: calcium carbonate; [0106] Additives: anti UV rays, flame retardants and dyes.