Tire

Abstract

To provide a tire capable of improving visibility of a tire mark.SOLUTION: The tire 10 includes a plurality of kinds of fluorescent parts in a tire ground contact area of a tire tread part, the plurality of kinds of fluorescent parts have mutually different fluorescent colors, and the plurality of kinds of fluorescent parts are arranged in mutually different areas.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a tire. [Background technology]

[0002] Depending on the driving conditions of a vehicle, tire marks may be left on the surface of the road. Tire marks include, for example, braking marks and skid marks. Tire marks contain a lot of important evidence in accident investigations. For example, they provide clues to the vehicle's speed, direction, braking timing, and road conditions. Patent Document 1 describes a tire with a colored area on the surface of the tread. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-94040 Summary of the Invention [Problem to be solved by the invention]

[0004] By providing a colored area on the surface of the tread, tire marks can be made more visible. However, there is a problem that tire marks may be difficult to leave or to see depending on the road surface and driving conditions.

[0005] Furthermore, when a colored area is provided on the surface of the tread, a coloring process is required during tire manufacturing. If the colored area is thin or overlaps with the circumferential grooves during the coloring process, there is a problem of reduced visibility. Furthermore, as the tire wears, the colored area becomes thinner, which reduces the visibility of tire tracks.

[0006] The present disclosure has been made in view of the above, and an object of the present disclosure is to provide a tire that can improve the visibility of tire marks. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the objectives, a tire according to one aspect of the present disclosure includes multiple types of fluorescent portions in the tire contact area of ​​the tire tread portion, the multiple types of fluorescent portions having different fluorescent colors from one another, and the multiple types of fluorescent portions being arranged in different areas from one another. [Effects of the Invention]

[0008] According to the present disclosure, the visibility of tire marks can be improved. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a meridian cross section of a tire according to this embodiment. [Figure 2] FIG. 2 is a plan view showing the tread surface of the tire shown in FIG. [Figure 3] FIG. 3 is a diagram showing another example of the arrangement of the fluorescent parts. [Figure 4] FIG. 4 is a diagram showing another example of the arrangement of the fluorescent parts. [Figure 5] FIG. 5 is a meridian cross section of a tire according to a modified example. [Figure 6] FIG. 6 is a plan view showing a tread surface of a tire according to another modified example. [Figure 7] FIG. 7 is a table showing the results of performance tests of tires according to embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description of each embodiment, components that are the same or equivalent to those in other embodiments will be assigned the same reference numerals, and their description will be simplified or omitted. The present invention is not limited to each embodiment. Furthermore, the components of each embodiment include those that are easily replaceable by those skilled in the art, or those that are substantially the same. Note that the configurations described below can be combined as appropriate. Furthermore, configurations can be omitted, replaced, or modified without departing from the spirit of the invention. The multiple modifications described in this embodiment can be combined as desired within the scope obvious to those skilled in the art.

[0011] (tire) FIG. 1 is a meridian cross-sectional view of a tire 10 according to this embodiment. FIG. 1 shows a meridian cross-sectional view of one side region in the tire radial direction. FIG. 1 also shows a radial tire for passenger cars as an example of the tire 10. The tire 10 is preferably a pneumatic tire. The gas to be filled into the tire 10 may be normal air or air with an adjusted oxygen partial pressure, or an inert gas such as nitrogen, argon, or helium.

[0012] In the following description, the meridian section of the tire refers to a section of the tire cut by a plane including the tire's rotation axis (not shown). The tire radial direction refers to a direction perpendicular to the tire's rotation axis (not shown), the tire radially inner side refers to the side toward the rotation axis in the tire radial direction, and the tire radially outer side refers to the side away from the rotation axis in the tire radial direction. The tire circumferential direction refers to a direction around the rotation axis as the central axis. The tire width direction refers to a direction parallel to the rotation axis, the tire widthwise inner side refers to the side toward the tire equatorial plane (tire equator line) CL in the tire width direction, and the tire widthwise outer side refers to the side away from the tire equatorial plane CL in the tire width direction. The tire equatorial plane CL is a plane perpendicular to the tire's rotation axis and passing through the center of the tire width of the tire 10. The tire width refers to the width in the tire width direction between portions located on outer sides in the tire width direction, i.e., the distance between portions farthest from the tire equatorial plane CL in the tire width direction. The tire equator line refers to a line that is on the tire equatorial plane CL and extends along the tire circumferential direction of the tire 10. In this embodiment, the tire equator line is given the same symbol "CL" as the tire equatorial plane.

[0013] The vehicle width direction inner side and vehicle width direction outer side are defined as the directions relative to the vehicle width direction when the tire is mounted on a vehicle. The left and right regions bounded by the tire equatorial plane are defined as the vehicle width direction outer region and the vehicle width direction inner region, respectively. The tire 10 also includes a mounting direction indicator (not shown) that indicates the tire mounting direction on the vehicle. The mounting direction indicator is configured, for example, by a mark or a bump on the tire sidewall. For example, ECER30 (Article 30 of the Economic Commission for Europe Regulation) requires that a vehicle mounting direction indicator be provided on the sidewall that will be on the vehicle width direction outer side when mounted on the vehicle.

[0014] As shown in FIG. 1, the tire 10 has an annular structure centered on the tire rotation axis, and includes a pair of bead cores 11, 11, a pair of bead fillers 12, 12, a carcass layer 13, a belt layer 14, a tread rubber 15, a pair of sidewall rubbers 16, 16, and a pair of rim cushion rubbers 17, 17 (see FIG. 1).

[0015] The pair of bead cores 11, 11 are formed by winding one or more steel bead wires in an annular and multiple pattern and are embedded in the bead portions to form the cores of the left and right bead portions. The pair of bead fillers 12, 12 are disposed on the outer periphery of the pair of bead cores 11, 11 in the tire radial direction, respectively, to reinforce the bead portions.

[0016] The carcass layer 13 has a single-layer structure consisting of one carcass ply or a multi-layer structure consisting of multiple carcass plies stacked together, and is toroidally laid between the left and right bead cores 11, 11 to form the tire framework. Both ends of the carcass layer 13 are wrapped around and secured to the outside in the tire width direction so as to enclose the bead cores 11 and the bead fillers 12. The carcass ply of the carcass layer 13 is formed by coating multiple carcass cords made of steel or organic fiber material (e.g., aramid, nylon, polyester, rayon, etc.) with coating rubber and rolling them, and has a carcass angle (defined as the inclination angle of the carcass cords in the longitudinal direction relative to the tire circumferential direction) of 80 degrees or more and 90 degrees or less in absolute value.

[0017] The belt layer 14 is formed by laminating a pair of cross belts 141, 142 and a belt cover 143, and is disposed around the outer periphery of the carcass layer 13. The pair of cross belts 141, 142 are formed by covering a plurality of belt cords made of steel or organic fiber material with coating rubber and rolling them, and have a belt angle of 20 degrees or more and 55 degrees or less in absolute value. The pair of cross belts 141, 142 have belt angles (defined as the inclination angle of the longitudinal direction of the belt cords with respect to the tire circumferential direction) of opposite signs to each other, and are layered with the longitudinal directions of the belt cords crossing each other (so-called cross-ply structure). The belt cover 143 is formed by covering belt cover cords made of steel or organic fiber material with coating rubber, and has a belt angle of 0 degrees or more and 10 degrees or less in absolute value. In addition, the belt cover 143 is, for example, a strip material made by covering one or more belt cover cords with coating rubber, and can be constructed by wrapping this strip material spirally around the outer peripheral surfaces of the cross belts 141, 142 multiple times in the tire circumferential direction.

[0018] The tread rubber 15 is disposed on the outer periphery of the carcass layer 13 and the belt layer 14 in the tire radial direction to form the tread portion of the tire (hereinafter referred to as the tire tread portion). A pair of sidewall rubbers 16, 16 are disposed on the outer sides of the carcass layer 13 in the tire width direction, respectively, to form left and right sidewall portions. A pair of rim cushion rubbers 17, 17 are disposed on the inner sides of the left and right bead cores 11, 11 and the turnup portions of the carcass layer 13 in the tire radial direction, respectively, to form the rim fitting surfaces of the bead portions. Part of the tread rubber 15 is fluorescent portions 41, 42, 43, and 44. The fluorescent portions 41, 42, 43, and 44 have a thickness in the tire radial direction.

[0019] [Tread pattern] Fig. 2 is a plan view showing the tread surface of the tire 10 shown in Fig. 1. Fig. 2 shows the tread pattern of an all-season tire. In Fig. 2, the tire circumferential direction refers to the direction around the tire rotation axis.

[0020] As shown in FIG. 2, the tire 10 has a plurality of circumferential main grooves 21-23 and circumferential narrow grooves 24 extending in the tire circumferential direction, and a plurality of land portions 31-35 defined by these circumferential grooves 21-24 on the tread surface.

[0021] Main grooves are grooves that are required by JATMA to display a wear indicator, and generally have a groove width of 3.0 mm or more and a groove depth of 6.0 mm or more. Lug grooves, which will be described later, are lateral grooves that extend in the tire width direction and function as grooves by opening when the tire is in contact with the ground. Sipes, which will be described later, are cuts formed on the tread surface and are distinguished from lug grooves in that they close when the tire is in contact with the ground.

[0022] The groove width is measured as the maximum distance between the left and right groove walls at the groove opening when the tire is mounted on a specified rim, inflated to a specified internal pressure, and under no load. When the land portion has a notch or chamfered edge, the groove width is measured at the intersection of the tread surface and an extension of the groove wall in a cross-sectional view normal to the groove length direction. When the groove extends in a zigzag or wavy pattern around the tire circumference, the groove width is measured at the center line of the groove wall amplitude.

[0023] The groove depth is measured as the maximum distance from the tread surface to the groove bottom when the tire is mounted on a specified rim, inflated to a specified internal pressure, and under no load. If the groove has partial unevenness or sipes at the groove bottom, the groove depth is measured excluding these.

[0024] A specified rim is a "standard rim" as specified by JATMA, a "design rim" as specified by TRA, or a "measuring rim" as specified by ETRTO. Furthermore, specified internal pressure is the "maximum air pressure" as specified by JATMA, the maximum value of the "tire load limits at various cold inflation pressures" as specified by TRA, or the "inflation pressure" as specified by ETRTO. Furthermore, specified load is the "maximum load capacity" as specified by JATMA, the maximum value of the "tire load limits at various cold inflation pressures" as specified by TRA, or the "load capacity" as specified by ETRTO. However, in JATMA, for passenger car tires, the specified internal pressure is 180 kPa, and the specified load is 88% of the maximum load capacity.

[0025] For example, in the configuration of FIG. 2, the tire 10 has a tread pattern that is asymmetrical about the tire equatorial plane CL. One circumferential narrow groove 21 and one circumferential main groove 22 are provided in an inner region in the vehicle width direction bounded by the tire equatorial plane CL. Two circumferential main grooves 23, 24 are provided in an outer region in the vehicle width direction bounded by the tire equatorial plane CL. In this specification, grooves extending in the circumferential direction may be referred to as circumferential grooves. Five rows of land portions 31-35 are defined by these circumferential grooves 21-24. One land portion 33 is disposed on the tire equatorial plane CL. The circumferential main grooves 22, 23, 24 have a straight shape with a constant groove width.

[0026] Additionally, the land portions 31, 35 on the outer side in the tire width direction, defined by the circumferential narrow groove 21 in the inner region in the vehicle width direction or the outermost main groove 24 in the outer region in the vehicle width direction, are defined as shoulder land portions. The shoulder land portions 31, 35 are the outermost land portions in the tire width direction and are located on the tire ground contact edge T. Additionally, the land portions 32, 34 on the inner side in the tire width direction, defined by the circumferential narrow groove 21 or the outermost main groove 24, are defined as second land portions. Additionally, the land portion 33 located closer to the tire equatorial plane CL than the second land portions 32, 34 is defined as a center land portion.

[0027] In Figure 2, the symbol T denotes the tire ground contact edge. The tire ground contact edge T is defined as the maximum axial width position of the contact surface between the tire and a flat plate when the tire is mounted on a specified rim, pressurized to a specified internal pressure, and placed perpendicular to a flat plate in a stationary state and subjected to a load corresponding to a specified load.

[0028] [Inner shoulder land area, inner second land area] 2, the shoulder land portion 31 includes a lug groove 313, a lug groove 211, and a lug groove 212. The lug grooves 313 are provided at predetermined intervals in the tire circumferential direction. One end of the lug groove 313 terminates within the shoulder land portion 31 without penetrating the shoulder land portion 31, extends in the tire width direction, and intersects with the tire ground contact edge T.

[0029] The lug grooves 211 and 212 extend in the tire width direction. The lug grooves 211 and 212 are alternately provided at predetermined intervals in the tire circumferential direction. The lug grooves 211 and 212 penetrate the circumferential narrow grooves 21. One ends of the lug grooves 211 and 212 terminate in the shoulder land portion 31. The other ends of the lug grooves 211 and 212 terminate in the second land portion 32.

[0030] [Center Land Area] 2, the center land portion 33 includes lug grooves 232. The lug grooves 232 are provided at predetermined intervals in the tire circumferential direction. One end of the lug groove 232 terminates in the center land portion 33. The other end of the lug groove 232 communicates with the circumferential main groove 23.

[0031] [Outer shoulder land area, outer second land area] The shoulder land portion 35 includes lug grooves 311 and narrow grooves 312. The lug grooves 311 and narrow grooves 312 terminate at one end within the shoulder land portion 35 without penetrating the shoulder land portion 35, extend in the tire width direction, and intersect with the tire ground contact edge T.

[0032] As shown in FIG. 2, the second land portion 34 includes a chamfered portion 321, and lug grooves 322 and narrow grooves 323 having different groove widths.

[0033] The chamfered portion 321 is formed on the edge portion of the second land portion 34 on the tire ground contact edge T side (i.e., on the outermost circumferential main groove 24 side), and connects the tread surface of the second land portion 34 to the groove wall surface of the outermost circumferential main groove 24 with a flat or curved surface. The chamfered portion 321 has a shape in which the chamfer width increases in the tire circumferential direction on the tread surface of the second land portion 34. A plurality of chamfered portions 321 are arranged at predetermined intervals in the tire circumferential direction.

[0034] The lug groove 322 is a first lateral groove arranged corresponding to the chamfered portion 321, and as shown in Figure 2, one end terminates within the second land portion 32 and the other end opens into the longitudinal center of the chamfered portion 231 and communicates with the outermost circumferential main groove 24.

[0035] [Fluorescent part] FIG. 2 shows an example of the arrangement of fluorescent portions. In FIG. 2, land portion 31 includes fluorescent portion 41. Land portion 32 includes fluorescent portion 42. Land portion 34 includes fluorescent portion 43. Land portion 35 includes fluorescent portion 44. Fluorescent portions 41, 42, 43, and 44 are formed from rubber containing a fluorescent material. A fluorescent material is a substance that emits fluorescence. Fluorescent portions 41, 42, 43, and 44 are part of tread rubber 15. By using rubber containing a fluorescent material during tire molding, fluorescent portions 41, 42, 43, and 44 can be provided at the positions shown in FIG. 2. Fluorescent portions 41, 42, 43, and 44 are provided between tire ground contact edges T, T, i.e., within the tire ground contact region. Fluorescent portions 41, 42, 43, and 44 extend continuously in the tire circumferential direction. Fluorescent portions 41, 42, 43, and 44 are arranged in different regions.

[0036] Fluorescent portions 41 and 42 shown in FIG. 2 have the same fluorescent color. Fluorescent portions 43 and 44 also have the same fluorescent color. Fluorescent portions 41 and 42 and fluorescent portions 43 and 44 have different fluorescent colors. Different fluorescent colors refer to, for example, a warm fluorescent color and a cool fluorescent color. For convenience of illustration, in FIG. 2 , fluorescent portions 41 and 42 are indicated by hatching, and fluorescent portions 43 and 44 are indicated by dots, to indicate different fluorescent colors. Tire 10 includes multiple types of fluorescent portions 41 and 42, 43 and 44 in the tire contact region of the tire tread, and the multiple types of fluorescent portions 41 and 42 and 43 and 44 have different fluorescent colors. The multiple types of fluorescent portions 41 and 42 and the multiple types of fluorescent portions 43 and 44 are arranged in different regions. By arranging multiple fluorescent portions in different regions in the tire contact region in this way, tire mark visibility and analytical accuracy are improved. More specifically, skid marks, which are traces of sudden braking, allow us to estimate the strength of the braking and the vehicle speed. Yaw marks, which are traces made when a vehicle skids, indicate that the vehicle has spun or slid. Acceleration marks, which are traces made when the tires dig into the ground during sudden acceleration, indicate that the traces were made by a particularly powerful vehicle or sports car.

[0037] Generally, tire marks are left on the road surface as a result of slippage between the road surface and the tire. As a result, tire marks are crushed, making tread pattern analysis (distinguishing tires) difficult in many cases. However, as shown in Figure 2, by placing multiple fluorescent areas in different positions, it becomes possible to distinguish them from other patterns. When tire marks made of fluorescent areas are made to function as identification lines, the process of applying the identification lines is unnecessary and the visibility of the identification lines is also improved. Identification lines are displayed on the tire tread surface, etc., and are used to identify tires during the tire manufacturing process. Furthermore, because the fluorescent areas remain until the later stages of wear, they also have a design effect and improve safety.

[0038] In FIG. 2, the width of each fluorescent portion 41, 42, 43, and 44, i.e., the length W in the tire width direction, is 2 mm or more. If the length W in the tire width direction is less than 2 mm, the visibility of tire marks will decrease, which is undesirable. The length W in the tire width direction is preferably 3 mm or more. The length W in the tire width direction may be the same as the width of the land portion. The length of the fluorescent portions 41, 42, 43, and 44 in the tire width direction is preferably equal to or less than the length of each land portion 31, 32, 34, and 35 in the tire width direction.

[0039] [Location of fluorescent part] As described above, each fluorescent portion shown in FIG. 2 extends continuously in the tire circumferential direction. FIG. 3 is a diagram showing another example of the arrangement of fluorescent portions. Fluorescent portions 42, 43, and 44 in FIG. 3 have the same configuration as in FIG. 2. The fluorescent portions provided in land portion 31 in FIG. 3 have a different configuration from that in FIG. 2. That is, fluorescent portions 41-1, 41-2, 41-3, 41-4... are provided intermittently in the tire circumferential direction in land portion 31. Arranging the fluorescent portions intermittently in the tire circumferential direction improves the visibility and analytical accuracy of tire marks, making it easier to identify the type of tire.

[0040] Here, the length L of each of the fluorescent portions 41-1, 41-2, 41-3, and 41-4 in the tire circumferential direction is 5 mm or more. If the length L in the tire circumferential direction is less than 5 mm, the visibility of tire marks will decrease, which is not preferable. The length L in the tire circumferential direction is preferably 6 mm or more.

[0041] 3, the fluorescent portions are provided intermittently in the tire circumferential direction in the land portion 31. This example is not limiting, and the fluorescent portions may be provided intermittently in the tire circumferential direction in the other land portions 32, 34, 35.

[0042] Returning to FIG. 2, fluorescent areas 41 and 42 are provided on the inside in the vehicle width direction. Fluorescent areas 43 and 44 are provided on the outside in the vehicle width direction. In other words, fluorescent areas of different fluorescent colors are provided on the inside and outside in the vehicle width direction of the tire tread. By arranging different fluorescent areas on the inside and outside in the vehicle width direction, distinctive tire tracks can be obtained, enabling detailed analysis.

[0043] FIG. 4 is a diagram showing another example of the arrangement of fluorescent areas. In FIG. 4, fluorescent areas 45 and 49 are provided in land areas 31 and 35 in the tire shoulder region Sh. Fluorescent areas 46, 47, and 48 are provided in land areas in the center region Ce other than the tire shoulder region. That is, in FIG. 4, fluorescent areas of different fluorescent colors are provided in the land areas in the tire shoulder region Sh and the land areas in the center region Ce other than the tire shoulder region in the tire tread. By providing fluorescent areas of different colors in the tire shoulder region and the center region, distinctive tire tracks can be obtained, enabling detailed analysis.

[0044] [Variation 1] Fig. 5 is a meridian cross-sectional view of tire 10a according to modified example 1. Fig. 5 is a diagram showing another example of the arrangement of fluorescent portions. As shown in Fig. 5, fluorescent portions 41a and 41b are provided in land portion 31 of tire 10a. Furthermore, fluorescent portions 44a and 44b are provided in land portion 35 of tire 10a. The fluorescent colors of fluorescent portions 41a and 41b are different from the fluorescent colors of fluorescent portions 44a and 44b.

[0045] The fluorescent portion 41a is disposed on the outer side in the tire radial direction, and the fluorescent portion 41b is disposed on the inner side in the tire radial direction of the fluorescent portion 41a. In other words, the fluorescent portion 41a is stacked on the outer side in the tire radial direction of the fluorescent portion 41b. The fluorescent portions 41a and 41b have the same fluorescent color. The amount of phosphor contained in the fluorescent portion 41b is greater than the amount of phosphor contained in the fluorescent portion 41a. The same applies to the fluorescent portions 44a and 44b, where the fluorescent portion 44a is disposed on the outer side in the tire radial direction, and the fluorescent portion 44b is disposed on the inner side in the tire radial direction of the fluorescent portion 44a. The fluorescent portion 44a is stacked on the outer side in the tire radial direction of the fluorescent portion 44b. The fluorescent portions 44a and 44b have the same fluorescent color. The amount of phosphor contained in the fluorescent portion 44b is greater than the amount of phosphor contained in the fluorescent portion 44a.

[0046] Compared to tire tracks in the early stages of wear, tire tracks in the later stages of wear have a darker fluorescent color. When new, rubber is soft and easily abraded, so the fluorescent material content is low. As rubber becomes harder and less abraded, the visibility of tire tracks improves by increasing the fluorescent material content.

[0047] 5, two fluorescent sections are stacked in the tire radial direction, but three or more fluorescent sections may be stacked. Even in this case, the fluorescent section on the inner side in the tire radial direction has a higher fluorescent substance content than the fluorescent section on the outer side in the tire radial direction.

[0048] [Variation 2] FIG. 6 is a plan view showing the tread surface of a tire 10b according to another modified example 2. Each of the fluorescent portions described above extends in the tire circumferential direction. In contrast, in the tire 10b shown in FIG. 6, fluorescent portions 51, 52, 53, and 54 extend in the tire width direction. Fluorescent portions 51, 52, 53, and 54 are provided in different regions. The fluorescent colors of fluorescent portions 51 and 52 are different from those of fluorescent portions 53 and 54. The width of fluorescent portions 51, 52, 53, and 54 in a direction perpendicular to the extending direction, i.e., the length W in the tire circumferential direction, is 2 mm or more. The length W in the tire width direction is preferably 3 mm or more. In the tire 10b shown in FIG. 6, multiple fluorescent portions are arranged in different positions, making them distinguishable from other patterns. When tire marks marked by fluorescent portions are to function as identification lines, a coating process for the identification lines is unnecessary, and the visibility of the identification lines is improved. Furthermore, the fluorescent part remains even after wear, which has a design effect and improves safety.

[0049] [Example] FIG. 7 is a table showing the results of performance tests of tires according to embodiments of the present disclosure.

[0050] In this performance test, evaluations of tire marks and identification lines were conducted for several types of test tires. Furthermore, a 245 / 40R18 97Y test tire was mounted on an 18x8J rim, and an internal pressure of 240 kPa and the specified JATMA load were applied to the test tire. The test tires were also mounted on all wheels of a test vehicle, a sedan (front engine, front drive). For the tire mark evaluation, drift driving and normal driving were conducted on a circuit to confirm the visibility and analyzability of tire marks. For the identification line evaluation, visibility was confirmed visually from a distance of 3 m.

[0051] The tires of Examples 1 to 7 are tires that have multiple types of fluorescent portions in the tire contact area of ​​the tire tread portion, and the multiple types of fluorescent portions have different fluorescent colors and are arranged in different areas. The tire of the conventional example is a tire that does not have a fluorescent portion. As shown by the test results, it is clear that the tires of the examples can improve the visibility of tire marks.

[0052] The present disclosure encompasses the following inventions. <1> A plurality of types of fluorescent parts are provided in the tire contact area of ​​the tire tread, the plurality of types of fluorescent portions have fluorescent colors different from one another, The plurality of types of fluorescent portions are arranged in different regions. tire. <2> The fluorescent portion is formed of rubber containing a fluorescent material. <1> A tire as described in <3> the fluorescent portion has a thickness in the tire radial direction, The amount of the fluorescent material contained in the region on the inner side in the tire radial direction is different from the amount of the fluorescent material contained in the region on the outer side in the tire radial direction. <2> A tire as described in <4> the fluorescent portion is provided in a land portion of the tire tread portion, The fluorescent portion extends continuously in the tire circumferential direction. <2> or <3> A tire as described in <5> the fluorescent portion is provided in a land portion of the tire tread portion, The fluorescent portion extends discontinuously in the tire circumferential direction. <2> or <3> A tire as described in <6> The length of each of the discontinuously extending fluorescent portions in the tire circumferential direction is 5 mm or more. <5> A tire as described in <7> The length of the fluorescent portion in the tire width direction is equal to or less than the length of the land portion in the tire width direction. <4> from <6> 1. A tire according to any one of the preceding items. <8> The length of the fluorescent part in the tire width direction is 2 mm or more. <1> from <7> 1. A tire according to any one of the preceding items. <9> In the tire tread portion, the fluorescent portions having different fluorescent colors are provided on the inner side and the outer side in the vehicle width direction. <1> from <8> 1. A tire according to any one of the preceding items. <10> In the tire tread portion, the fluorescent portions having different fluorescent colors are provided in the land portions in the inner region in the vehicle width direction and the land portions in the outer region in the vehicle width direction. <1> from <8> 1. A tire according to any one of the preceding items. <11> In the tire tread portion, the fluorescent portions are provided in different fluorescent colors between the land portion in the tire shoulder region and the land portion in the center region other than the tire shoulder region. <1> from <8> 1. A tire according to any one of the preceding items. <12> the fluorescent portion is provided in a land portion of the tire tread portion, The fluorescent portion extends continuously in the tire width direction. <2> or <3> A tire as described in <13> the fluorescent portion is provided in a land portion of the tire tread portion, The fluorescent portion extends discontinuously in the tire width direction. <2> or <3> A tire as described in [Explanation of symbols]

[0053] 10, 10a, 10b tires 11 Bead core 12 Bead filler 13 Carcass layer 14 Belt Layer 15 Tread rubber 16 Sidewall rubber 17 Rim cushion rubber 21 Circumferential thin groove 22, 23, 24 Circumferential main groove 31, 35 Shoulder land area 32, 34 Second Land Section 33 Center Land Division 41, 41-1, 41-2, 41-3, 41-4, 41-4, 41a, 41b, 42, 43, 44, 44a, 44b, 45, 46, 47, 48, 49, 51, 52, 53, 54 Fluorescent part 141, 142 Cross Belt 143 Belt cover 211, 212, 232, 311, 313, 322 lug grooves 231, 321 Chamfered part 312, 323 narrow groove T Tire contact edge

Claims

1. A plurality of types of fluorescent parts are provided in the tire contact area of ​​the tire tread, the plurality of types of fluorescent portions have fluorescent colors different from one another, The plurality of types of fluorescent portions are arranged in different regions. tire.

2. The fluorescent portion is formed of rubber containing a fluorescent material.

2. The tire of claim 1.

3. the fluorescent portion has a thickness in the tire radial direction, The amount of the fluorescent material contained in the region on the inner side in the tire radial direction is different from the amount of the fluorescent material contained in the region on the outer side in the tire radial direction.

3. The tire of claim 2.

4. the fluorescent portion is provided in a land portion of the tire tread portion, The fluorescent portion extends continuously in the tire circumferential direction. The tire according to claim 2 or claim 3.

5. the fluorescent portion is provided in a land portion of the tire tread portion, The fluorescent portion extends discontinuously in the tire circumferential direction. The tire according to claim 2 or claim 3.

6. The length of each of the discontinuously extending fluorescent portions in the tire circumferential direction is 5 mm or more.

6. The tire of claim 5.

7. The length of the fluorescent portion in the tire width direction is equal to or less than the length of the land portion in the tire width direction.

5. The tire of claim 4.

8. The length of the fluorescent part in the tire width direction is 2 mm or more. The tire according to claim 1 or claim 2.

9. In the tire tread portion, the fluorescent portions having different fluorescent colors are provided on the inner side and the outer side in the vehicle width direction. The tire according to claim 1 or claim 2.

10. In the tire tread portion, the fluorescent portions having different fluorescent colors are provided in the land portions in the inner region in the vehicle width direction and the land portions in the outer region in the vehicle width direction. The tire according to claim 1 or claim 2.

11. In the tire tread portion, the fluorescent portions are provided in different fluorescent colors between the land portion in the tire shoulder region and the land portion in the center region other than the tire shoulder region. The tire according to claim 1 or claim 2.

12. the fluorescent portion is provided in a land portion of the tire tread portion, The fluorescent portion extends continuously in the tire width direction. The tire according to claim 2 or claim 3.

13. the fluorescent portion is provided in a land portion of the tire tread portion, The fluorescent portion extends discontinuously in the tire width direction. The tire according to claim 2 or claim 3.

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