JP2009174225A - Elastic pavement - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an elastic pavement having a surface layer part 2 and a water retentive layer part 3 constituted by connecting rubber chips 10 respectively, and allowing easy setting of a temperature sensing point when utilizing thermosensitive water absorbing and discharging resin 11 in the water retentive layer part 3 and achieving sufficient cooling effect without relying on the environment of construction. <P>SOLUTION: This elastic pavement is constituted by mixing and kneading thermal insulation pigment formed by an infrared ray reflection material with the rubber chips 10 in the surface layer part 2 of an elastic tile 1 used for paving and letting the water retentive layer part 3 contain a plurality of kinds of thermosensitive water absorbing and discharging resin 11 having different temperature sensing points. The water retentive layer part 3 has a laminated structure composed of an upper layer 3a, a middle layer 3b, and a lower layer 3c laminated in this order from a surface layer part 2 side. Preferably, the temperature sensing points of the water absorbing and discharging resin 11 included in each layer 3a-3c are different from each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an elastic pavement mainly formed by bonding rubber chips, and particularly belongs to the technical field of the structure having a water retaining layer.

  Conventionally, it is known to use a rubber material excellent in shock-absorbing property as a paving material, and in recent years, the use is expanding to public facilities such as a jogging course and a pool as well as a children's playground in a park, for example. As such an elastic pavement, as described in Patent Documents 1 and 2, a rubber chip solidified in a block shape with a resin binder such as urethane has been put into practical use, which is relatively light and easy to construct. It also has the advantage of.

Moreover, in the thing of these patent documents 1 and 2, a water retention layer is provided in the back side of the elastic layer (surface layer) which consists of rubber chips, and while maintaining the function of elastic pavement, the pavement surface temperature rises in summer, and consequently the temperature I try to suppress the rise. The water-retaining layer contains a temperature-sensitive water-absorbing / releasing resin, and if the temperature of the water-retaining layer rises to a certain value (temperature-sensitive point) due to heat transmitted from the surface layer, moisture is released and due to latent heat of vaporization. Cooling is performed.
Japanese Patent No. 3982794 JP 2003-138509 A

  By the way, when using a temperature-sensitive water-absorbing / releasing resin, the temperature (temperature-sensitive point) at which it switches between the water-absorbing state and the water-releasing state should be set appropriately according to the climatic conditions of the construction environment. The temperature rise can be effectively suppressed, but the setting of this temperature sensitive point is not easy, and it is sufficient if the timing of moisture release deviates even slightly from the requirements of the construction environment. The effect is often not obtained.

  As an example, park walkways and jogging courses usually do not have very thick pavement, and the water retention capacity is naturally reduced, and the water supply tends to occur less frequently in those places, so the temperature rises. There is a demand to release the water little by little to increase the duration of the effect.

  However, if the pavement is not so thick, the temperature rise on the surface is easily transmitted to the lowest layer, and the overall temperature tends to rise early (that is, the temperature gradient inside the pavement becomes gentle). For this reason, if the temperature sensitive point of the water-absorbing / releasing resin is set to be low, the moisture in the lowermost layer will be released in a relatively short period of time after the temperature rise has exceeded the temperature sensitive point on the surface side due to the temperature rise. The time during which it is released and thereby the cooling effect is obtained is rather shortened.

  On the other hand, if construction is done in a place where the user walks barefoot, such as in a poolside, it is most important to prevent low-temperature burns, etc. The temperature of the pavement surface to be reduced must be reduced more effectively.

  However, a large temperature gradient occurs inside the pavement at poolsides and so on that have received strong direct light, so even if the surface layer reaches the temperature sensing point and the release of moisture begins, it is quite difficult in the lower part of the pavement. Water discharge does not start, and the water discharge amount temporarily becomes insufficient with respect to the temperature rise, and it is difficult to sufficiently suppress the temperature rise of the pavement surface.

  In view of such problems, the object of the present invention is to make it possible to easily set the temperature-sensitive point even when a temperature-sensitive water-absorbing / releasing resin is used for the water-retaining layer portion, even if the construction environment is different. The purpose is to obtain a sufficient cooling effect.

  In order to achieve the above object, the elastic pavement of the present invention is first provided with a surface layer portion in which rubber chips are bonded by a binder and a back side of the surface layer portion as described in claim 1, and the rubber chips are formed by a binder. And a water retention layer portion containing a plurality of types of temperature-sensitive water-absorbing / releasing water resins (hereinafter also abbreviated as water-absorbing / releasing water-absorbing resins) having different temperature-sensing points.

  With such a configuration, since a plurality of types of water-absorbing / releasing water resins having different temperature-sensitive points are contained, the entire water-retaining layer portion has a certain width to the temperature-sensitive point, that is, the temperature at which water absorption and water discharge are switched. Therefore, a certain degree of cooling effect can be obtained even if the setting is not performed strictly.

  In addition, considering that the temperature rises in order from the surface layer side in the water retaining layer part, it is possible to lengthen the water discharge time due to the temperature rise by appropriately distributing multiple types of water-absorbing and releasing water resins corresponding to the temperature gradient. On the other hand, since the cooling effect can be increased by shortening the length, it is possible to realize characteristics more suitable for the construction environment.

  More specifically, for example, the water-absorbing / releasing resin is distributed in such a manner that many of the temperature-sensitive points are relatively high on the surface layer side and many of the temperature-sensitive points are relatively high on the opposite side. If it is (Claim 3), the time (water discharge time) from the start of water discharge on the surface layer side of the water retention layer portion to the start of water discharge even at the bottom can be made longer due to the temperature rise.

  Therefore, the cooling effect can be maintained for a relatively long time even in a place where the pavement cannot be made too thick or in an environment where the frequency of water supply is low, and an increase in the temperature of the pavement surface and hence the ambient temperature can be suppressed. This is suitable for places that do not usually have very thick pavements, such as park walkways and jogging trails. Suitable for places that do not rise.

  On the other hand, in places such as a poolside where strong direct sunlight is received during the summer, the temperature rises particularly near the surface of the pavement, and a large temperature gradient tends to occur downward from there. In this case, in order to more reliably suppress the temperature rise of the pavement surface where the user walks barefoot, it is only necessary to quickly release moisture from the bottom of the water retention layer, which tends to be delayed in temperature rise. Contrary to the above, the water-absorbing / releasing resin is distributed so that the surface layer portion has a relatively high temperature sensitive point and the opposite side has a relatively low temperature sensitive point. (Claim 5).

  In addition, if it is an environment where water supply is naturally performed and the frequency is high as in the poolside, the duration of water discharge may not be so long.

  Moreover, in order to appropriately distribute a plurality of types of water-absorbing / releasing resins as described above, it is preferable that the water-retaining layer portion is constituted by a plurality of layers, and the temperature sensitive points of the water-absorbing / releasing resins contained in each layer are respectively set. (Claims 4 and 6).

  Furthermore, it is preferable to suppress an increase in temperature due to solar radiation by including an infrared reflecting material in the surface layer portion of the elastic pavement (claim 2). This is especially effective in places where it is exposed to direct sunlight, such as in the poolside, and it can reduce the heat received by the direct sunlight and suppress the rise in surface temperature. This is also advantageous in quickly discharging water from the bottom to the lower layer.

  Of course, even when it is constructed on a walking path in a park or the like, it is preferable to reduce the heat reception due to direct sunlight as described above in order to suppress the temperature rise of the pavement surface and the environment together with the release of moisture from the water retention layer.

  As described above, according to the elastic pavement according to the present invention, a plurality of types of temperature-sensitive water-absorbing / absorbing resins having different temperature-sensitive points are contained in the water-retaining layer portion, so that the temperature-sensitive point has a certain width. Since the cooling effect due to the release of moisture can be obtained relatively easily, and the water absorbing / releasing resin is appropriately distributed in correspondence with the temperature gradient in the water retaining layer. It is possible to obtain characteristics that match various construction environments such as parks and poolsides.

  Further, if the surface layer portion contains an infrared reflecting material, it is possible to reduce heat reception due to solar radiation, and it is possible to effectively suppress the temperature rise of the surface layer portion, and to moderate the temperature gradient, which is preferable particularly in a poolside or the like. The characteristics can be realized.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

  FIG. 1 shows an embodiment of an elastic tile 1 for elastic paving according to the present invention. The elastic tile 1 includes a surface layer portion 2 and a water retention layer portion 3 in which rubber chips 10, 10,... Are joined by a binder (not shown), and the water retention layer portion 3 is integrally provided on the back side of the surface layer portion 2. It has been. In the illustrated example, the elastic tile 1 has a rectangular plate shape, and the vertical and horizontal dimensions are both 300 to 600 mm and the thickness is 50 to 100 mm.

  As an example, the rubber chips 10, 10,... Have a particle diameter of about φ1 to φ10 mm, preferably about φ2 to φ5 mm, and may be solid or foam rubber material, or a mixture thereof. It may be. Moreover, not only a granular thing but the thing of a elbow shape (fiber chip) may be contained. A gap is formed between the rubber chips 10, 10,... To ensure the required water permeability.

  The rubber chips 10, 10,... Are, for example, vulcanized rubber compositions such as natural rubber, ethylene propylene rubber (EPR), ethylene propylene diene monomer rubber (EPDM), styrene butadiene rubber (SBR), and nitrile rubber (NBR). Can be mentioned. From the viewpoint of effectively recycling the rubber material, it is preferable to pulverize and use the rubber composition recovered from the waste tire or the industrial rubber waste material, but a rubber chip can also be manufactured from the virgin rubber material. Note that the rubber chip can be constituted by a single kind or a mixture of plural kinds.

  Examples of the binder include MDI-based and IPDI-based urethane resins. From the viewpoint of preventing discoloration (yellowing) due to ultraviolet rays, it is preferable to use an IPDI-based urethane resin for the surface layer portion 2. The content of the binder is preferably 3 to 20%, more preferably 5 to 10% with respect to 100 parts by mass of the rubber chip in consideration of a balance between water permeability and strength.

  Thus, the elastic tile 1 mainly formed by the rubber chips 10, 10,... Has an advantage that it has excellent cushioning properties and is relatively lightweight and easy to construct. For example, a park walkway, a children's playground, a rooftop, etc. It is suitable for utility space or poolside, etc., but on the other hand, there is a tendency for the temperature to rise due to heat storage of rubber material. For example, when laying on the poolside, the surface is exposed to direct sunlight in the summer. There was a possibility that the temperature would rise to around 70 ° C.

  On the other hand, in this embodiment, as a feature of the present invention, a known heat shielding pigment made of an infrared reflecting material is kneaded into the rubber chips 10, 10,... Of the surface layer portion 2 to suppress a temperature rise due to direct light. . As such a heat-shielding pigment, known ones can be used as appropriate, for example, trade name NSB-V6380 series infrared reflective pigments manufactured by Resino Color Industry Co., Ltd. can be used. If the pigment is kneaded into the rubber chip in this way, the gap between the chips is not blocked as in the case of thermal barrier coating, which is advantageous in ensuring water permeability. Moreover, the rubber chips 10, 10,... Of the surface layer portion 2 exposed on the surface can be colored with the pigment.

  Then, if the surface layer 2 contains a heat-shielding pigment, the absorption rate of infrared rays is reduced and the heat reception itself by direct sunlight is reduced, so the surface layer part 2 and the water retaining layer part below the paved surface as well. The temperature rise of 3 can also be effectively suppressed.

  Further, in the water retention layer 3, as schematically shown in an enlarged manner in FIG. 1 (b), powdery temperature-sensitive water-absorbing / releasing resins 11, 11,. Hereinafter, abbreviated as a water absorbing / releasing resin) is dispersed and supported. This water-absorbing / releasing resin 11, 11,... Is a well-known resin that swells by absorbing moisture at a temperature lower than the temperature-sensitive point, and that shrinks by releasing the absorbed moisture as the temperature rises. As described in Patent Document 1, as an example, it is possible to use an acrylamide derivative as a main component monomer and a copolymer obtained by copolymerizing a hydrophilic monomer and crosslinking it (such as Thermogel manufactured by Kojin Co., Ltd.). it can. The temperature sensitive point can be appropriately set by selecting the copolymerization ratio of monomers.

  In this embodiment, the water-retaining layer portion 3 has a laminated structure composed of three layers of an upper layer 3a, an intermediate layer 3b, and a lower layer 3c, and the temperature sensitive points of the water-absorbing and releasing water resins 11, 11,. Thus, the cooling characteristics due to the latent heat of vaporization of the moisture released by the temperature rise are appropriately set according to the requirements of the construction environment. That is, when the temperature of the elastic tile 1 rises in the summer as described above, the temperature of the surface layer portion 2 first rises, and subsequently, the temperature also rises in the water retaining layer portion 3 in order from the surface layer side (that is, from the top). Then, as shown in FIG. 2A, a temperature gradient is generated in which the temperature gradually decreases from the upper layer 3a toward the lower layer 3c.

  On the other hand, the temperature sensitive points (shown as 3a, 3b, 3c in the figure) of the water-absorbing / releasing water-absorbing resins 11, 11,... Contained in each of the upper layer 3a, the middle layer 3b, and the lower layer 3c are as shown in the figure. The upper layer 3a on the side is the lowest (for example, about 30 ° C.), and the middle layer 3b and the lower layer 3c are increased in this order (for example, about 35 ° C., 40 ° C.). If the temperature sensing point is set to be high, the time from when the temperature of the upper layer 3a first reaches the temperature sensing point and water discharge starts until the water discharge starts at the lower layer 3c can be made considerably long.

  If water is released little by little over time in this way, the pavement cannot be made too thick and it is difficult to secure the capacity of the water-retaining layer 3, or even in an environment where the frequency of water supply is low Since the cooling effect due to the latent heat of vaporization can be maintained, the cooling effect per hour is not so high, but it is possible to suppress the temperature of the pavement surface and hence the atmospheric temperature from rising over a relatively long period.

  This is suitable when the pavement cannot be made too thick due to cost, such as a park walkway or jogging course, and the temperature does not rise so rapidly during the day as in a covered children's playground. Suitable for location.

  On the other hand, for example, when constructed on the pool side, the surface temperature of the elastic tile 1 tends to rise suddenly in direct sunlight during the summer day. As a result, a relatively steep temperature gradient occurs. When used in such an environment, the upper layer 3a, the middle layer 3b, and the lower layer 3c, in the order of the upper layer 3a, the middle layer 3b, and the lower layer 3c, the temperature sensitive points of the water absorbing / releasing resins 11, 11,. If the temperature of 3a becomes a temperature sensitive point (for example, about 50 ° C.), the temperature of the middle layer 3b and the lower layer 3c also becomes the temperature sensitive point (for example, about 45 ° C., 40 ° C.), so that water discharge starts without delay. Good.

  In this way, even when the temperature gradient in the water retention layer 3 is large as shown in the figure, moisture contained in the water-absorbing / releasing water-absorbing resins 11, 11,... From each of the upper layer 3a, the middle layer 3b, and the lower layer 3c quickly. Since the cooling effect due to the latent heat of vaporization becomes very high, it is possible to sufficiently suppress the temperature rise at the poolside that receives direct sunlight as described above, and for users walking barefoot there It is possible to prevent the occurrence of problems such as low temperature burns. In addition, if it is an environment where water supply is naturally performed and the frequency is high as in the poolside, the duration of water discharge may not be so long.

  Therefore, in the pavement using the elastic tile 1 as in this embodiment, the heat reception due to the direct sunlight is reduced by kneading the heat insulating pigment made of the infrared reflecting material into the rubber chips 10, 10,. In addition to suppressing the temperature rise of both the surface layer portion 2 and the water retention layer portion 3, the water retention layer portion 3 has a three-layer structure, and each layer 3 a to 3 c has a structure corresponding to a temperature gradient generated when the temperature rises. By making the temperature-sensitive points of the water-absorbing / releasing water-absorbing resins 11, 11,... Different from each other, moisture is released little by little so that the cooling effect due to the latent heat of vaporization can be maintained for a long time. Can be increased. Therefore, higher effects can be obtained by adapting to the requirements of different construction environments such as parks and poolsides.

  The water retaining layer 3 is not limited to a three-layer structure, and may be a two-layer structure or a four-layer or more structure. The water-absorbing / releasing water-absorbing resin 11, 11,. When the water-retaining layer portion 3 is composed of one or two layers, the thickness of the elastic tile 1 can be reduced to about 30 mm.

  Further, it is not always necessary to make the water-absorbing / releasing resins 11, 11,... Have a required distribution state, and only a plurality of types of water-absorbing / releasing resins 11, 11,. However, since the temperature-sensitive point can be given a certain width as the entire water-retaining layer part 3, there is an advantage that the setting becomes easy.

  Furthermore, it is not necessarily a requirement of the present invention that the surface layer portion 2 contains a heat-shielding pigment, but it goes without saying that it is preferable to suppress the temperature rise itself of the pavement surface by containing the heat-shielding pigment.

-Example-
The graph of FIG. 3 (a) shows the experimental results of measuring how the surface temperature rises by heating several types of elastic tiles including those of the above embodiment. The graph a is the one in which the surface layer portion 2 contains a heat shielding pigment as in the embodiment, and the water retaining layer portion 3 contains the water absorbing / releasing water-repellent resins 11, 11,... However, in this embodiment, the water-retaining layer portion 3 is not formed in a laminated structure, and a plurality of types of water-absorbing / releasing water resins 11, 11,.

  On the other hand, in the graph b, although the surface layer portion 2 contains a heat shielding pigment, the water retaining layer portion 3 is not provided, and the rubber chips 10, 10,... That do not contain the water absorbing / releasing resin 11, 11,. A layer is provided (Comparative Example 1). Graph c is that of Comparative Example 2 in which the water-retaining layer part 3 is not provided as in Comparative Example 1 and the surface layer part 2 does not contain a heat-shielding pigment.

  FIG. 2 (b) shows an outline of the experimental apparatus. A specimen E (the above-mentioned Examples, Comparative Examples 1 and 2) set in Case C is irradiated from above with a halogen lamp L. For example, from a thermocouple A signal from the temperature sensor S is recorded in time series. Then, the irradiation distance H by the halogen lamp L is set so that the surface temperature of the comparative example 2 reaches the target temperature of 60 to 70 ° C. in about 3 hours. Under these conditions, each of the examples and the comparative examples is set. Changes in the surface temperature were measured.

  When the graphs b and c are compared, it can be seen that the surface layer portion 2 can contain a heat-shielding pigment as in Comparative Example 1 to suppress an increase in surface temperature. Furthermore, when comparing graphs a and b, it is possible to suppress the temperature rise by providing the water retaining layer portion 3, and in particular, for about 2 hours from the start of the experiment, the temperature rise is effectively caused by the latent heat of vaporization of the released water. You can see that it is delayed.

  Moreover, if the water retention layer part 3 is made into a laminated structure like the elastic tile 1 of the embodiment, and the temperature sensitive points of the water absorbing / releasing water resins 11, 11,... Of the respective layers 3a to 3c are made different, the shape of the graph a changes. At the same time as the temperature rise suppression time changes, it is considered that the temperature rise suppression allowance changes during that time. That is, if the temperature sensing point is increased from the surface layer toward the lower layer side, the temperature rise can be suppressed for a relatively long period of time as indicated by the broken line graph a ′, while the temperature sensing point is directed toward the lower layer side. If it is made lower, the initial temperature suppression effect is estimated to increase as shown by the dashed line a ″.

  In the elastic pavement formed by bonding rubber chips, the present invention easily optimizes the cooling effect due to the latent heat of vaporization of moisture according to the construction environment when a water-retaining water layer is provided using a temperature-sensitive water-absorbing / releasing resin. It is extremely useful because it can.

It is a perspective view (a) of the elastic tile which concerns on embodiment, and sectional drawing (b) which expands and shows a part. It is explanatory drawing which shows the relationship between the temperature gradient which arises in a water retention layer part, and the setting of the temperature sensitive point corresponding to this. FIG. 4 is a graph (a) of an experimental result showing how the surface temperature of an elastic tile rises, and a schematic configuration diagram (b) of the experimental apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Elastic pavement 2 Surface layer part 3 Water retention layer part 3a Upper layer 3b Middle layer 3c Lower layer 10 Rubber chip 11 Temperature-sensitive water-absorbing and releasing resin

Claims (6)

A surface layer part in which rubber chips are bonded by a binder;
A water retaining layer portion provided on the back side of the surface layer portion, combined with a rubber chip by a binder, and containing a plurality of types of temperature-sensitive water-absorbing / releasing water resins each having a different temperature-sensitive point;
Elastic pavement characterized by comprising.   The elastic pavement according to claim 1, wherein the surface layer portion contains an infrared reflecting material.   Multiple types of temperature-sensitive water-absorbing / releasing water-repellent resin in the water-retaining layer part are those with relatively low temperature points on the surface layer side, and those with relatively high temperature points on the opposite side. The elastic pavement according to claim 1, wherein the elastic pavement is distributed.   The water-retaining layer part is composed of multiple layers, the surface layer side layer has more temperature-sensitive water-absorbing / releasing water-resin, and the opposite layer has a higher temperature point. The elastic pavement according to claim 3, wherein the number of the pavement is increased.   Multiple types of temperature-sensitive water-absorbing / releasing water-repellent resins in the water-retaining layer part have a relatively high temperature-sensitive point on the surface layer side, and a relatively low temperature-sensitive point on the opposite side. The elastic pavement according to claim 1, wherein the elastic pavement is distributed.   The water-retaining layer is composed of multiple layers, the surface layer side layer has a higher temperature-sensitive water-absorbing and releasing resin, and the opposite layer has a lower temperature point. The elastic pavement according to claim 5, characterized in that the number is increased.

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