Elastic pavement and construction method thereof

Abstract

To provide a colored elastic chip capable of suppressing the temperature rise of a pavement surface.SOLUTION: In the colored elastic chip 11 having a granular elastic core 11a and a colored coating 11a for coating and coloring the surfaces of the elastic core 11b, the elastic core 11a is formed of a transparent or translucent urethane elastomer. The colored resilient chips 11 can be used, for example, in a resilient pavement 100 comprising the colored resilient chips 11 and a binder 20. The temperature of the elastic pavement 100 hardly rises as compared with a conventional elastic pavement.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a colored elastic chip for paving and a method for producing the same. The present invention also relates to an elastic pavement using the colored elastic chip. [Background technology]

[0002] In nurseries, parks, and other facilities, roads and floors are covered with elastic pavement to cushion the impact on the body from the road or floor when walking or falling. Elastic pavement made from granular elastic chips (rubber chips) made from an elastic material is widely used. While this type of elastic chips may be made from crushed waste tires, colored waste tire chips are often used. The use of colored waste tire chips allows the elastic pavement to be finished in a variety of colors and patterns.

[0003] For example, Figure 1(a) of Patent Document 1 describes a colored rubber chip 9 that includes a dark-colored rubber chip material 1 such as waste tire chips, a base colored coating 6 provided on the surface of the rubber chip material 1, and a finish colored coating 7 provided on top of the base colored coating 6. In this colored rubber chip 9, the base colored coating 6 is provided to make the base color of the rubber chip material 1 (waste tire chips) less visible from the outside, and allows the color of the finish colored coating 7 to be vividly developed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-047691 Summary of the Invention [Problem to be solved by the invention]

[0005] However, elastic pavement using colored waste tire chips such as the colored rubber chips 9 described in Patent Document 1 has a problem in that the surface temperature of the elastic pavement is easily increased by sunlight or the like.

[0006] The present invention has been made to solve the above problems, and aims to provide a colored elastic chip that can suppress the temperature rise of the pavement surface. It is also an object of the present invention to provide a method for manufacturing the colored elastic chip and an elastic pavement using the colored elastic chip. [Means for solving the problem]

[0007] The above issues are: a granular elastic core; a colored coating for coating and coloring the surface of the elastic core; A colored elastic tip comprising: The elastic core is formed of a transparent or translucent urethane elastomer. Colored Elastic Chip This is solved by providing

[0008] The colored elastic chips of the present invention use an elastic core made of a transparent or translucent urethane elastomer, which enhances the heat-shielding performance of the colored elastic chips and, as will be shown in the examples below, helps to suppress temperature increases on the pavement surface.

[0009] Since pavement surfaces such as elastic pavements are typically used in a manner where people and vehicles pass over them, gradual wear of the surface layer of elastic chips is inevitable after construction. In this regard, conventional elastic pavements using colored waste tire chips have a problem in that, when the surface layer of colored waste tire chips wears, the black rubber of the waste tire chips becomes exposed and conspicuous, detracting from the aesthetic appearance of the elastic pavement. In contrast, the colored elastic chips of the present invention employ a transparent or translucent urethane elastomer as the elastic core. Because urethane elastomers have excellent abrasion resistance and mechanical strength, their use can reduce the abrasion resistance of the colored elastic chips. Furthermore, the use of a transparent or translucent urethane elastomer reduces the color of the elastic core, even if the colored elastic chips wear and expose the elastic core. This reduces the aesthetic appearance of the pavement surface over time after construction.

[0010] In the colored elastic tip of the present invention, the colored coating is preferably formed from a urethane-based paint. This allows the colored coating to better fit with the elastic core formed from a urethane elastomer, making it less likely for the colored coating to peel off from the elastic core. Furthermore, this also increases the wettability of the paint forming the colored coating with respect to the elastic core, making it easier to form a uniform colored coating on the surface of the elastic core.

[0011] In the colored elastic tip according to the present invention, the urethane elastomer forming the elastic core can be either an ether-based urethane elastomer made primarily of polyether-based polyol and isocyanate, or an ester-based urethane elastomer made primarily of polyester-based polyol and isocyanate. Ether-based urethane elastomers have excellent hydrolysis resistance. On the other hand, ester-based urethane elastomers tend to have better mechanical strength than ether-based urethane elastomers.

[0012] However, ester-based urethane elastomers tend to have poorer hydrolysis resistance than ether-based urethane elastomers. Therefore, when using an ester-based urethane elastomer as the urethane elastomer forming the elastic core, it is preferable to use one or two polyester-based polyols selected from the group consisting of polyethylene adipate (PEA), polybutylene adipate (PBA), polyhexylene adipate (PHA), and a copolymer of ethylene adipate and butylene adipate (PEABA) as the polyester-based polyol. This improves the hydrolysis resistance of the elastic core (ester-based urethane elastomer).

[0013] In the colored elastic tip according to the present invention, it is preferable that the elastic core is made from waste material, which reduces the environmental impact and also reduces the manufacturing costs of the colored elastic tip.

[0014] The colored elastic chips of the present invention are not limited to specific uses as long as they are used for paving. For example, the colored elastic chips of the present invention can be used in elastic paving containing the colored elastic chips and a binder. This makes it possible to provide elastic paving that is resistant to temperature rise.

[0015] This elastic pavement may contain only the colored elastic chips of the present invention as elastic chips. However, because the urethane elastomer forming the elastic core of the colored elastic chips is relatively hard, it may be difficult for an elastic pavement using only colored elastic chips as elastic chips to provide sufficient cushioning. Furthermore, when an ester-based urethane elastomer is used as the urethane elastomer, ester-based urethane elastomers tend to be less hydrolysis-resistant than other elastomers. Therefore, if only colored elastic chips are used as elastic chips, there is a risk that the cushioning properties of the elastic pavement will be impaired or the elastic pavement will collapse if adverse conditions are met and the colored elastic chips (elastic core) undergo hydrolysis.

[0016] Therefore, it is preferable that this elastic pavement further contains non-urethane elastic chips (hereinafter simply referred to as "non-urethane elastic chips") with a Type A hardness (rubber hardness measured at 25°C using a Type A durometer in accordance with JIS K6253; the same applies below) of 65 or less. In other words, it is preferable to use a mixture of colored elastic chips and non-urethane elastic chips as the elastic chips. By mixing colored elastic chips with relatively soft non-urethane elastic chips, it becomes easier to increase the cushioning properties of the elastic pavement. In addition, even if the colored elastic chips (the elastic cores of the colored elastic chips) undergo hydrolysis, it is possible to prevent the elastic pavement from losing its cushioning properties or collapsing.

[0017] It should be noted that a "non-urethane elastic tip" may or may not have a coating (painting) on ​​its surface. If a non-urethane elastic tip has a coating, the coating does not have to be non-urethane, and as long as the core material covered by the coating is made of a non-urethane material (even if the coating is urethane), it will be included in the "non-urethane elastic tip." The same applies hereinafter.

[0018] In elastic paving containing colored elastic chips and a binder, it is preferable to use an uncolored IPDI-based urethane resin or an uncolored HDI-based urethane resin as the binder. Here, "uncolored" refers to the absence of pigments or dyes for coloring purposes. Therefore, "uncolored" binders include those that retain the color of the material itself and those that appear slightly colored due to the addition of additives (e.g., fillers) for purposes other than coloring. Uncolored binders are highly versatile because they can be used regardless of the color of the colored elastic chips. Furthermore, because IPDI-based urethane resins and HDI-based urethane resins are resistant to yellowing, using them can help maintain the appearance of elastic paving closer to its original condition at the time of construction. [Effects of the Invention]

[0019] As described above, the present invention makes it possible to provide colored elastic chips that can suppress temperature increases on pavement surfaces. It also makes it possible to provide a method for manufacturing the colored elastic chips and elastic pavement using the colored elastic chips. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a schematic cross-sectional view of an elastic pavement according to an embodiment of the present invention. [Figure 2] FIG. 1 is a schematic diagram showing a state in which an irradiation test is being performed. DETAILED DESCRIPTION OF THE INVENTION

[0021] 1. Overview A preferred embodiment of the present invention will be described in more detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view of an elastic pavement 100 of this embodiment. As shown in FIG. 1, the elastic pavement 100 of this embodiment comprises a primer layer 110 applied to the surface to be paved S, and an elastic layer 120 laminated on the upper (outer) side of the primer layer 110. The primer layer 110 serves to firmly bond the surface to be paved S and the elastic layer 120. The elastic layer 120 is made up of a large number of elastic chips 10 bound together by a binder 20, and has cushioning properties. There are gaps between the elastic chips 10, which gives the elastic layer 120 water permeability.

[0022] The elastic tip 10 includes a colored elastic tip 11. As shown in Fig. 1, the colored elastic tip 11 is an elastic tip that includes a granular elastic core 11a and a colored coating 11b that coats and colors the surface of the elastic core 11a. The elastic core 11a is made of a transparent or translucent urethane elastomer.

[0023] The colored elastic chips 11 have excellent heat-shielding properties because the elastic core 11a is transparent or translucent. By using the colored elastic chips 11, the elastic pavement 100 of this embodiment can suppress surface temperature rise compared to general elastic pavement using EPDM rubber chips, as will be shown in the examples below. Furthermore, even when the surface layer of the elastic pavement 100 wears and the elastic core 11a is exposed, the color of the elastic core 11a is less noticeable, so the aesthetic appearance of the elastic pavement 100 is less likely to be marred. Furthermore, urethane elastomers have excellent abrasion resistance and mechanical strength. Therefore, by using colored elastic chips 11 having an elastic core 11a formed from urethane elastomer, the abrasion resistance and mechanical strength of the elastic pavement 100 can be improved.

[0024] The elastic tip 10 included in the elastic layer 120 can be a colored elastic tip 11 alone. However, in this embodiment, as shown in FIG. 1 , a mixture of the colored elastic tip 11 and a non-urethane elastic tip 12 having a Type A hardness (a rubber hardness measured at 25°C using a Type A durometer in accordance with JIS K6253; the same applies below) of 65 or less is used as the elastic tip 10. The reason for this is as follows. As will be explained later, the colored elastic tip 11, whose elastic core 11a is made of a urethane elastomer, is relatively hard. Therefore, if the elastic layer 120 is formed using only this colored elastic tip 11, the elastic layer 120 may become too hard (the cushioning properties of the elastic layer 120 may become insufficient). In this regard, in this embodiment, the colored elastic tip 11 is mixed with the relatively soft non-urethane elastic tip 12 to prevent the elastic layer 120 from becoming too hard.

[0025] As will be explained in detail later, in this embodiment, the elastic core 11a is made of an ester-based urethane elastomer, which tends to have poorer hydrolysis resistance than other elastomers. Therefore, by using a mixture of the colored elastic chips 11 and the non-urethane-based elastic chips 12, even if the colored elastic chips 11 (the elastic core 11a) undergo hydrolysis, it is possible to prevent the elastic layer 120 from losing its cushioning properties or collapsing.

[0026] When a mixture of colored elastic chips 11 and non-urethane elastic chips 12 is used as the elastic chips 10 forming the elastic layer 120, the proportion of the colored elastic chips 11 in the elastic chips 10 is not limited. However, if the proportion of the colored elastic chips 11 is too high, it may be difficult to enhance the cushioning properties of the elastic layer 120, or there may be a greater risk that the cushioning properties of the elastic layer 120 will be lost or the elastic layer 120 will collapse in the event of hydrolysis. For this reason, it is preferable that the proportion of the colored elastic chips 11 in the elastic chips 10 be 50% by weight or less. The proportion of the colored elastic chips 11 in the elastic chips 10 may also be 40% by weight or less, or 30% by weight or less.

[0027] In this embodiment, the elastic layer 120 forms the outermost layer of the elastic pavement 100. However, in other embodiments, a protective layer to protect the elastic layer 120 or an anti-slip layer to improve anti-slip properties may be provided on the upper side (outside) of the elastic layer 120. In still other embodiments, another layer (for example, a cushioning layer to improve the impact resistance of the elastic pavement 100) may be provided between the paved surface S and the primer layer 110, or between the primer layer 110 and the elastic layer 120.

[0028] 2. Colored elastic chips As shown in FIG. 1, the colored elastic tip 11 comprises an elastic core 11a and a colored coating 11b. There are no limitations on the size of the colored elastic tip 11, but if it is too large, the surface of the elastic layer 120 may become uneven, potentially making it uncomfortable to walk on. For this reason, the size of the non-urethane elastic tip 12 is preferably 4 mm or less, and more preferably 3.5 mm or less. However, if the colored elastic tip 11 is too small, the spaces between the colored elastic tips 11 may become too crowded (making it difficult to create gaps between the colored elastic tips 11), potentially reducing the water permeability of the elastic layer 120. For this reason, the size of the colored elastic tip 11 is preferably 0.5 mm or more, and more preferably 1 mm or more.

[0029] The hardness of the colored elastic chip 11 is not limited. However, if the colored elastic chip 11 is too hard, the elastic pavement 100 may not have sufficient cushioning properties. For this reason, the Type A hardness of the colored elastic chip 11 is preferably 95 or less, and more preferably 92 or less. However, if the colored elastic chip 11 is too soft, it may be difficult to increase the abrasion resistance and mechanical strength of the colored elastic chip 11 (elastic pavement 100). For this reason, the Type A hardness of the colored elastic chip 11 is preferably 65 or more, and more preferably 70 or more. The colored elastic chip 11 in this embodiment has a Type A hardness of about 90.

[0030] 2.1 Elastic core The elastic core 11a is formed of a transparent or translucent urethane elastomer. Here, the term "transparent or translucent" means that the total light transmittance of the urethane elastomer (the average value of the total light transmittance measured in the wavelength range of 400 nm to 700 nm using a 2 mm thick test piece in accordance with JIS K7361-1; the same applies hereinafter) is 50% or more. The total light transmittance of the urethane elastomer can be 60% or more, 70% or more, or 80% or more. The upper limit of the total light transmittance of the urethane elastomer is usually 98% or less.

[0031] Although thermosetting urethane elastomers and thermoplastic urethane elastomers are known as urethane elastomers, it is preferable to use a thermosetting urethane elastomer as the urethane elastomer for forming the elastic core 11a, as this can improve the heat resistance of the elastic core 11a.

[0032] The urethane elastomer is formed from polyol and isocyanate as main raw materials. Hereinafter, the polyol and isocyanate, which are the main raw materials of the urethane elastomer that forms the elastic core 11a, may be referred to as the "core polyol" and the "core isocyanate," respectively.

[0033] Urethane elastomers are generally broadly divided into ester-based urethane elastomers, which are primarily made from polyester-based polyols and isocyanates, and ether-based urethane elastomers, which are primarily made from polyether-based polyols and isocyanates. Ether-based urethane elastomers have excellent hydrolysis resistance. Therefore, using a polyether-based polyol as the core polyol can improve the durability of the elastic core 11a, thereby further improving the durability of the elastic pavement 100. On the other hand, ester-based urethane elastomers have excellent mechanical strength. Therefore, using a polyester-based polyol as the core polyol can improve the abrasion resistance and mechanical strength of the elastic core 11a, thereby further improving the abrasion resistance and mechanical strength of the elastic pavement 100. As the core polyol, either a polyester-based polyol or a polyether-based polyol can be used alone, or a combination of a polyester-based polyol and a polyether-based polyol can be used.

[0034] Whether the urethane elastomer forming the elastic core 11a is an ester-based urethane elastomer or an ether-based urethane elastomer can be verified by cutting the colored elastic chip 11 to expose the elastic core 11a and analyzing the surface of the exposed elastic core 11a by FTIR analysis ATR method. In the ATR spectrum, the 1720 cm spectrum derived from the ester bond is -1 When a strong peak appears around 1090 cm , it can be determined that the elastic core 11a is formed of an ester-based urethane elastomer, and the peak at 1090 cm originating from an ether bond -1 When a strong peak appears in the vicinity, it can be determined that the elastic core 11a is made of an ether-based urethane elastomer.

[0035] When a polyether polyol is used as the core polyol, the specific type thereof is not limited. Examples of polyether polyols that can be used include polytetramethylene ether glycol, polyoxypropylene triol, polyethylene glycol, and polypropylene glycol. As the core polyol, only one type of polyether polyol can be used, or two or more types of polyether polyols can be used in combination.

[0036] When a polyester polyol is used as the core polyol, the specific type is not limited. Polyester polyols are broadly classified into aliphatic polyester polyols and aromatic polyester polyols. It is preferable to use an aliphatic polyester polyol as the core polyol. Examples of core polyols that can be used include polyethylene adipate (PEA), polybutylene adipate (PBA), polyhexylene adipate (PHA), and a copolymer of ethylene adipate and butylene adipate (PEABA). This enhances the hydrolysis resistance of the elastic core 11a (urethane elastomer). The core polyol can be made of one type of polyester polyol or a combination of two or more types of polyester polyols. In this embodiment, the core polyol is made of polybutylene adipate (PBA), a polyester polyol.

[0037] The type of isocyanate for the core is also not limited. Examples of isocyanates that can be used for the core include diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and derivatives thereof. Only one type of isocyanate can be used for the core, or two or more types of isocyanates can be used in combination. In this embodiment, 4,4'-diphenylmethane diisocyanate (MDI) is used as the isocyanate for the core.

[0038] When the elastic core 11a is formed of an ester-based urethane elastomer (when a polyester-based polyol is used as the core polyol), a hydrolysis inhibitor can be included in the ester-based urethane elastomer. This can improve the hydrolysis resistance of the elastic core 11a (ester-based urethane elastomer). The specific type of hydrolysis inhibitor is not limited. Examples of hydrolysis inhibitors that can be used include carbodiimide derivatives, epoxy compounds, isocyanate compounds, acid anhydrides, oxazoline compounds, and melamine compounds. One type of hydrolysis inhibitor can be used alone, or two or more types can be used in combination.

[0039] The urethane elastomer forming the elastic core 11a preferably contains an antistatic agent. This is because the elastic core 11a is typically produced by pulverizing lumps of urethane elastomer in a pulverizer. If the urethane elastomer is prone to static electricity, the urethane elastomer pieces may stick together during pulverization, forming clumps and making it difficult to pulverize uniformly. Examples of the antistatic agent include conductive agents such as ionic conductive agents. Examples of the ionic conductive agent include imidazolium salts, pyridinium salts, ammonium salts, phosphonium salts, sulfonium salts, borates, metal salts, and surfactants. The antistatic agent may be used alone or in combination.

[0040] The urethane elastomer forming the elastic core 11a preferably does not contain fillers (e.g., carbon black, silica, calcium carbonate, etc.). This is because, when a rubber material containing fillers (e.g., scrap tires) is used as the elastic core, chalking due to the fillers tends to occur over time. By not including fillers, chalking is less likely to occur. Furthermore, not including fillers can improve the transparency of the elastic core 11a. Here, "not including fillers" in the urethane elastomer means that fillers were not intentionally added during the production of the urethane elastomer, not that the urethane elastomer does not contain fillers even as impurities. Therefore, even if a trace amount of filler is mixed into the urethane elastomer as an impurity, it is considered "not including fillers" as long as the filler was not intentionally added. The same applies hereinafter.

[0041] In addition to the above, the urethane elastomer forming the elastic core 11a may contain a urethane catalyst (which may be of the same type as or different from the urethane catalyst used in the coating film curing process), a chain extender, a crosslinking agent, a flame retardant, a plasticizer, etc.

[0042] The elastic core 11a may be made from virgin rubber, but in this embodiment, the elastic core 11a is manufactured from waste material. That is, waste material made from urethane elastomer is procured and crushed in a crusher to prepare granular elastic core 11a. This reduces the environmental impact associated with the production of the colored elastic tip 11 and also reduces costs.

[0043] 2.2 Colored coating The colored coating 11b is preferably made of a urethane-based paint, although the material is not limited thereto. This allows the colored coating 11b to better fit the elastic core 11a made of urethane elastomer. In addition, it also improves the wettability of the paint to the elastic core 11a. In this embodiment, an MDI (diphenylmethane diisocyanate)-based urethane paint is used as the urethane-based paint.

[0044] The colored coating 11b (urethane paint) contains a colorant (pigment). The type of pigment is not limited, but a heat-shielding pigment is preferable. This further improves the heat-shielding performance of the colored elastic chip 11. As the heat-shielding pigment, various pigments with heat-shielding properties can be used, but those with high reflectivity to light in the infrared range (infrared-reflecting heat-shielding pigments) are particularly preferred. The amount of pigment added to the elastic core 11a is not limited. The amount of pigment added to 100 parts by weight of the elastic core 11a is preferably about 1 to 5 parts by weight, and more preferably about 2 to 3 parts by weight.

[0045] The color of the colored coating 11b (pigment color) is not particularly limited. However, since the elastic core 11a used in this embodiment is made of urethane elastomer, it tends to yellow over time due to exposure to ultraviolet rays, etc. Therefore, depending on the color of the colored coating 11b, if the colored elastic chip 11 wears and the colored coating 11b partially peels off, exposing the yellowed elastic core 11a, the color tone of the elastic pavement 100 may change significantly from the time of construction, potentially damaging the aesthetic appearance. For this reason, it is preferable to use brown, beige, moss green, ochre, etc. as the color of the colored coating 11b. This makes it possible to make the yellowing of the elastic core 11a less noticeable.

[0046] The colored coating 11b (urethane-based paint) in this embodiment contains a urethanization catalyst. The urethanization catalyst is intended to promote the curing (urethanization) of the urethane-based paint. There are no specific restrictions on the type of urethanization catalyst. For example, an amine-based catalyst, a metal-based catalyst, or the like can be used as the urethanization catalyst.

[0047] In conventional colored elastic chips that use waste tire chips or the like as the elastic core, multiple layers of colored coating 11b are sometimes provided to conceal the black color of the elastic core. In contrast, in this embodiment, as shown in FIG. 1, only one layer of colored coating 11b is provided. Because a transparent or translucent elastic core 11a is used, even with only one layer of colored coating 11b (even if the elastic core 11a is somewhat visible through the coating), the color of the elastic core 11a is not noticeable, and the color of colored coating 11b is perceived as the dominant color. By providing only one layer of colored coating 11b, the manufacturing process for the colored elastic chip 11 can be simplified, reducing manufacturing costs.

[0048] 2.3 Manufacturing method of colored elastic chips The colored elastic chip 11 of this embodiment can be manufactured by stirring and mixing the elastic core 11a and the paint for forming the colored coating 11b to form a coating film on the surface of the elastic core 11a.

[0049] That is, by adding the elastic core 11a, colorant (pigment), MDI-based urethane prepolymer, and urethane catalyst in this order to a mixer and stirring and mixing, a cured urethane coating film can be formed on the surface of the elastic core 11a. The amount of the MDI-based urethane prepolymer is not limited, but is preferably about 1 to 10 parts by weight, and more preferably about 2 to 5 parts by weight, per 100 parts by weight of the elastic core 11a. The amount of the pigment is also not limited, but is preferably about 1 to 5 parts by weight, and more preferably about 2 to 3 parts by weight, per 100 parts by weight of the elastic core 11a.

[0050] 2.4 Uses of colored elastic chips In this embodiment, as shown in FIG. 1, colored elastic chips 11 are used in an elastic pavement 100 (the colored elastic chips 11 are used in a state where they are bound together with a binder 20). However, the colored elastic chips 11 can also be used for other purposes. For example, the colored elastic chips 11 can also be used as paving material in a loose state (not bound together with a binder 20). More specifically, for example, the colored elastic chips 11 can be used as an infill material for artificial turf.

[0051] 3. Non-urethane elastic tip The Type A hardness of the non-urethane elastic tip 12 is set to be equal to or less than 65. There is no particular limit to the lower limit of the Type A hardness of the non-urethane elastic tip 12, but it is preferably equal to or greater than 50, and more preferably equal to or greater than 55. The size of the non-urethane elastic tip 12 can be the same as that of the colored elastic tip 11.

[0052] There are no specific limitations on the type of non-urethane elastic tip 12 as long as it is made of a non-urethane material. Examples of the non-urethane elastic tip 12 that can be used include rubber tips and thermoplastic elastomer tips molded into chip shapes.

[0053] When the non-urethane elastic chip 12 is a rubber chip, examples of the raw rubber for the rubber chip include ethylene propylene diene rubber (EPDM), ethylene propylene rubber (EPM), styrene butadiene rubber (SBR), butadiene rubber (BR), butyl rubber (IIR), acrylonitrile butadiene rubber (NBR), acrylic rubber (ACM), natural rubber (NR), isoprene rubber (IR), chloroprene rubber (CR), chlorosulfonated polyethylene rubber (CSM), epichlorohydrin rubber (ECO), silicone rubber (Q), and fluororubber (FKM, FEPM). The rubber chip may be made from only one type of raw rubber, or may be made by blending multiple types of raw materials. Alternatively, multiple types of rubber chips made from different raw rubbers may be mixed and used.

[0054] On the other hand, examples of thermoplastic elastomers that can be used include styrene-based elastomers, olefin-based elastomers, vinyl chloride-based elastomers, chlorinated polyethylene-based elastomers, chlorosulfonated ethylene-based elastomers, polyester-based elastomers, polyamide-based elastomers, silicone-based elastomers, acrylic-based elastomers, and fluorine-based elastomers. As with the raw rubber of the rubber chips, the thermoplastic elastomers may be used alone or in combination.

[0055] In this embodiment, non-foamed rubber chips made from ethylene propylene diene rubber (EPDM) are used as the non-urethane elastic chips 12. EPDM has excellent impact resilience and hydrolysis resistance. Therefore, by using EPDM rubber chips as the non-urethane elastic chips 12, the cushioning properties of the elastic pavement 100 can be improved, and even in the unlikely event that hydrolysis occurs in the colored elastic chips 11, the cushioning properties of the elastic pavement 100 can be more easily maintained and the elastic pavement 100 can be more resistant to crumbling.

[0056] The non-urethane elastic chips 12 can be colored or uncolored. When colored non-urethane elastic chips 12 are used, the coloring method is not limited. In this embodiment, the non-urethane elastic chips 12 are elastic chips with a colorant kneaded into the interior (formed from an elastic material kneaded with a colorant such as a pigment). This makes it easier to maintain the color tone of the elastic pavement 100 close to that at the time of construction, even when the surface layer of the elastic pavement 100 wears. In other embodiments, the non-urethane elastic chips 12 can be equipped with an elastic core (not shown) and a colored coating (not shown), similar to the colored elastic chips 11. In this case, the elastic core of the non-urethane elastic chips 12 must be non-urethane, but the colored coating of the non-urethane elastic chips 12 may be urethane. The colored coating of the non-urethane elastic chips 12 can have a configuration similar to that described for the colored coating 11b of the colored elastic chips 11. The colorant (pigment) used to color the colored elastic tip 11 may be the same as or different from the colorant (pigment) used to color the non-urethane elastic tip 12. The color of the non-urethane elastic tip 12 is not limited, but for the same reasons as the colored elastic tip 11, it is preferable to use brown, beige, moss green, ochre, etc.

[0057] 4. Binder The binder 20 is not limited to a specific type. It is preferable to use an uncolored urethane resin as the binder 20. Examples of urethane resins used as the binder 20 include IPDI (isophorone diisocyanate)-based urethane resins, HDI (hexamethylene diisocyanate)-based urethane resins, and MDI (diphenylmethane diisocyanate)-based urethane resins. Of these, it is preferable to use IPDI-based urethane resins or HDI-based urethane resins. This makes it possible to make the binder 20 less prone to yellowing after application. In this embodiment, an IPDI-based urethane resin, which is less prone to yellowing than HDI-based urethane resins, is used as the binder 20.

[0058] However, IPDI-based urethane resins and HDI-based urethane resins tend to have slower curing rates than MDI-based urethane resins. If the binder 20 cures too slowly, people may walk on the elastic pavement 100 before the binder 20 cures, causing deformation of the elastic pavement 100 or the adhesion of dirt to the surface of the elastic pavement 100, resulting in poor construction. In this regard, as already mentioned, in this embodiment, the colored coating 11b of the colored elastic chips 11 contains a urethane-forming catalyst. Therefore, as will be described later, when the colored elastic chips 11 and the binder 20 are mixed during construction, the action of the urethane-forming catalyst in the colored coating 11b promotes the curing (urethane formation) of the binder 20. Therefore, even when an IPDI-based urethane resin or HDI-based urethane resin is used as the binder 20, the curing rate can be prevented from becoming too slow.

[0059] 5.Construction method The elastic pavement 100 can be constructed by going through a primer layer formation process in which a primer layer 110 (Figure 1) is formed, and an elastic layer formation process in which an elastic layer 120 is formed on top of the primer layer 110 formed in the primer layer formation process.

[0060] In the primer layer forming step of this embodiment, a primer layer 110 is formed by applying a primer to the surface S to be paved. A urethane-based primer is preferably used as the primer. The primer layer forming step may be performed once or may be performed two or more times. When the primer layer forming step is performed two or more times, the type of primer used each time may be the same or different.

[0061] In the elastic layer forming step of this embodiment, the elastic layer 120 is directly applied onto the primer layer 110 formed in the primer layer forming step. That is, the colored elastic chips 11, the non-urethane elastic chips 12, and the uncured binder 20 are mixed to prepare an elastic layer composition, which is then applied onto the primer layer 110 and rolled with a roller or the like to form the elastic layer 120. This allows construction to be carried out on site while taking into consideration detailed layout, for example.

[0062] On the other hand, in another embodiment, the elastic layer 120 can be formed by laying a pre-formed elastic paving material (not shown) on the primer layer 110 in the elastic layer formation process. In this case, the primer layer 110 is formed with a urethane adhesive (a urethane adhesive layer is used as the primer layer 110). This allows the elastic paving material to be firmly adhered to the paving surface S. The elastic paving material can be molded, for example, by mixing colored elastic chips 11, non-urethane elastic chips 12, and an uncured binder 20 to obtain an elastic layer composition, and then placing the resulting mixture in a mold and curing the binder 20. The elastic paving material can be shaped, for example, into tiles, blocks, or the like. [Example]

[0063] The elastic pavement 100 according to the present invention will be described in more detail below using more specific experimental examples, but the embodiments of the present invention are not limited to the following examples.

[0064] [Manufacturing colored elastic chips] Transparent or translucent urethane elastomer waste, primarily made from polybutylene adipate (PBA) and 4,4'-diphenylmethane diisocyanate (MDI), was crushed in a crusher and sieved to a diameter of 1 mm to 3.35 mm to prepare elastic cores. To 100 parts by weight of the resulting elastic cores, 3 parts by weight of an infrared-reflective heat-shielding pigment, 3 parts by weight of an MDI-based urethane prepolymer, and an amine catalyst were added, in that order, and stirred and mixed in a mixer to form a colored coating, yielding colored elastic chips. The color of the colored coating was brown.

[0065] [Sample preparation] (Sample 1) 50 parts by weight of the colored elastic chips obtained in the above "Production of Colored Elastic Chips" were mixed with 50 parts by weight of brown EPDM rubber chips containing an infrared-reflective heat-shielding pigment (10 parts by weight of heat-shielding pigment per 100 parts by weight of EPDM), and an IPDI-based urethane binder was further added to obtain an elastic layer composition. The obtained elastic layer composition was poured into a press mold and press-molded into a tile shape. The size of the obtained tile-shaped sample (Sample 1) was approximately 300 mm long, 300 mm wide, and 10 mm thick.

[0066] (Sample 2) Sample 2 was prepared in the same manner as Sample 1, except that no colored elastic chips were used, and only the same heat-shielding pigment-containing EPDM rubber chips as those used in Sample 1 were used as elastic chips.

[0067] (Sample 3) Sample 3 was prepared in the same manner as Sample 1, except that ordinary brown EPDM rubber chips were used instead of the colored elastic chips and the heat-shielding pigment-containing EPDM rubber chips.

[0068] [Irradiation test] Figure 2 is a schematic diagram showing the irradiation test in progress. The irradiation test was carried out according to the following procedure. For each of samples 1 to 3 obtained in [Sample Preparation], an irradiation test was carried out in accordance with (4) Appendix-3 "Indoor Irradiation Test Method for Heat Shielding Pavement" in the September 1, 2011 revised edition of "Heat Shielding Pavement Technical Data" published by the Road Surface Temperature Rise Suppression Pavement Research Group. However, the irradiation test was carried out in a normal room at room temperature (approximately 25°C), not in a constant temperature room.

[0069] (irradiation test) [1] The tile-shaped samples (samples 1 to 3) obtained by the above method were placed inside a polystyrene foam insulation material, as shown in Figure 1. The insulation material had a substantially flat bottom surface and side surfaces that could surround the tile-shaped samples on all four sides, and the size of the recess surrounded by the side surfaces was approximately the same as that of the tile-shaped samples (i.e., the size of the recess was approximately 300 mm in length and width, and the depth of the recess was approximately 50 mm). The thickness of the bottom surface of the insulation material was approximately 50 mm. [2] A beam lamp was placed above the tile-shaped sample using a lamp stand (not shown). A diffused incandescent lamp, BRF110V 150W or 120W (manufactured by Toshiba Lightech) was used as the beam lamp. Using a weight (not shown), the position of the beam lamp was adjusted so that the center of the beam lamp was positioned approximately vertically directly above the horizontal center point of the tile-shaped sample, and the inclination of the beam lamp was adjusted so that the irradiation surface of the beam lamp was approximately horizontal. The distance from the top surface of the tile-shaped sample to the irradiation surface of the beam lamp was approximately 600 mm. [3] A probe (thermocouple) was attached to the approximate center of the top surface of the tile-shaped sample to measure the surface temperature of the tile-shaped sample. [4] The insulation is enclosed on all four sides by a cardboard cover, which reduces the convection of surrounding air. [5] The beam lamp was turned on and temperature measurements were started. Temperature measurements were taken every 10 minutes for the first 60 minutes, and every 30 minutes thereafter. 90 minutes after the start of lighting, it was confirmed that the temperature change of the sample had reached equilibrium, and temperature data was obtained at that point.

[0070] (result) In Samples 1 and 2, the surface temperature after 90 minutes of irradiation only rose to about 50°C. In contrast, in Sample 3, the surface temperature after 90 minutes of irradiation rose to about 58°C. [Explanation of symbols]

[0071] 10 Elastic Tip 11 Colored Elastic Tips 11a Elastic Core 11b Colored coating 12 Non-urethane elastic tip 20 Binder 100 Elastic pavement 110 Primer layer 120 Elastic layer S Paved surface

Claims

1. a granular elastic core; a colored coating for coating and coloring the surface of the elastic core; A colored elastic tip comprising: The elastic core is formed of a transparent or translucent urethane elastomer. Colored elastic chips.

2. 2. The colored elastic chip according to claim 1, wherein the colored coating is formed from a urethane paint.

3. The urethane elastomer is a polyether polyol; Isocyanate and It is an ether-based urethane elastomer whose main raw material is The colored elastic tip according to claim 1.

4. The urethane elastomer is A polyester polyol, Isocyanate and It is an ester-based urethane elastomer whose main raw material is The colored elastic tip according to claim 1.

5. 5. The colored elastic tip according to claim 4, wherein the polyester polyol is one or two polyester polyols selected from the group consisting of polyethylene adipate (PEA), polybutylene adipate (PBA), polyhexylene adipate (PHA), and a copolymer of ethylene adipate and butylene adipate (PEABA).

6. 2. The colored elastic chip according to claim 1, wherein the elastic core is made of a waste material.

7. A method for producing the colored elastic chip according to any one of claims 1 to 6.

8. An elastic pavement comprising the colored elastic chips according to any one of claims 1 to 6 and a binder.

9. 9. The elastic pavement according to claim 8, further comprising non-urethane elastic chips having a Type A hardness of 65 or less.

10. 9. The elastic pavement according to claim 8, wherein the binder is an uncolored IPDI-based urethane resin or an uncolored HDI-based urethane resin.

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