Tire

Abstract

To provide a tire capable of improving visibility of a marking section and a holding performance of wax.SOLUTION: This tire includes a marking section 2 formed in a tire side surface. The marking section 2 includes: a housing 21 formed in the tire side surface; and a plurality of ridges 22 projecting from a bottom surface of the housing 21 and arrayed in parallel in a predetermined direction. A height H22 of the ridges 22 is within a range of 1.00≤H22 / H21 with respect to a depth H21 of the housing 21. A pitch length P22 of the plurality of ridges 22 is within a range of 0.05 [mm]≤P22≤0.50 [mm].SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a tire, and more particularly to a tire capable of improving the visibility performance of a logo portion and the wax retention performance.

Background Art

[0002] In recent tires, there is a problem that the logo (tire manufacturer, tire brand, etc.) formed on the tire side portion should be blackened in order to improve the visibility performance. As a conventional tire related to such a problem, the technique described in Patent Document 1 is known.

[0003] At the same time, there is also a problem that the peeling of the wax applied to the tire side portion should be suppressed to enhance the wax retention performance. As a conventional tire related to such a problem, the technique described in Patent Document 2 is known.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of the present invention is to provide a tire capable of improving the visibility performance of a logo portion and the wax retention performance.

Means for Solving the Problems

[0006] In order to achieve the above object, a tire according to the present invention is a tire provided with a logo portion formed on a tire side surface, wherein the logo portion is composed of a housing formed on the tire side surface and a plurality of ridges protruding from a bottom surface of the housing and arranged in parallel in a predetermined direction, a height H22 of the ridge satisfies 1.00 ≦ H22 / H21 with respect to a depth H21 of the housing, and a pitch length P22 of the plurality of ridges is in a range of 0.05 [mm] ≦ P22 ≦ 0.50 [mm].

Advantages of the Invention

[0007] In the tire according to the present invention, (1) since the logo portion is composed of a plurality of ridges arranged in the housing, the logo portion is blackened in a plan view of the tire side portion, improving the visibility of the logo portion and also improving the retention of the wax applied to the logo portion. Further, (2) since the height H22 of the ridge is in the above range with respect to the depth H21 of the housing, the wax is easily applied to the top of the ridge, further improving the retention of the wax in the logo portion. Furthermore, (3) since the pitch length P22 of the plurality of ridges is in the above range, the blackening effect of the logo portion by the ridges is improved. As a result, there is an advantage that the visibility of the logo portion and the retention of the wax are improved.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited by this embodiment. In addition, the components of this embodiment include those that can be replaced and are self-evidently replaceable while maintaining the identity of the invention. Further, a plurality of modified examples described in this embodiment can be arbitrarily combined within the scope self-evident to those skilled in the art.

[0010] [Tire] FIG. 1 is a cross-sectional view in the tire meridian direction showing a tire 1 according to an embodiment of the present invention. The figure shows a cross-sectional view of one side region in the tire radial direction of the tire 1 mounted on a rim 20. In this embodiment, as an example of the tire, a pneumatic radial tire for a passenger car will be described.

[0011] In the figure, the cross-section in the tire meridian direction is defined as the cross-section when the tire is cut by a plane including the tire rotation axis (not shown). Also, the tire equatorial plane CL is defined as a plane passing through the midpoint of the tire cross-sectional width defined by JATMA and perpendicular to the tire rotation axis. Also, the tire width direction is defined as the direction parallel to the tire rotation axis, and the tire radial direction is defined as the direction perpendicular to the tire rotation axis. Also, point T is the tire ground end, and point Ac is the tire maximum width position.

[0012] The tire 1 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, tread rubber 15, a pair of sidewall rubbers 16, 16, and a pair of rim cushion rubbers 17, 17 (see Fig. 1).

[0013] The pair of bead cores 11, 11 are formed by winding one or more bead wires made of steel in an annular and multiple manner, and are embedded in the bead portions to constitute the cores of the left and right bead portions. The pair of bead fillers 12, 12 are respectively arranged on the outer circumference in the tire diameter direction of the pair of bead cores 11, 11 to reinforce the bead portions.

[0014] The carcass layer 13 has a single-layer structure composed of a single carcass ply or a multi-layer structure formed by laminating a plurality of carcass plies, and is bridged in a toroidal shape between the left and right bead cores 11, 11 to constitute the skeleton of the tire. Further, both ends of the carcass layer 13 are wound back and locked to the outside in the tire width direction so as to wrap the bead core 11 and the bead filler 12. The carcass ply of the carcass layer 13 is formed by coating a plurality of carcass cords made of steel or an organic fiber material (for example, aramid, nylon, polyester, rayon, etc.) with coat rubber and performing rolling processing, and has a cord angle of 80° or more and 100° or less (defined as the inclination angle of the longitudinal direction of the carcass cord with respect to the tire circumferential direction).

[0015] The belt layer 14 is formed by laminating a plurality of belt plies 141 to 143, and is arranged to be wound around the outer circumference of the carcass layer 13. The belt plies 141 to 143 include a pair of crossed belts 141, 142 and a belt cover 143.

[0016] The pair of intersecting belts 141 and 142 are formed by coating a plurality of belt cords made of steel or organic fiber material with coating rubber and then performing rolling processing, and have a cord angle (defined as the inclination angle of the longitudinal direction of the belt cord with respect to the tire circumferential direction) of 15° or more and 55° or less in absolute value. Also, the pair of intersecting belts 141 and 142 have cord angles of opposite signs to each other, and the longitudinal directions of the belt cords intersect with each other and are laminated (so-called cross-ply structure). Further, the pair of intersecting belts 141 and 142 are laminated and arranged on the outer side in the tire radial direction of the carcass layer 13.

[0017] The belt cover 143 is formed by coating a belt cover cord made of steel or organic fiber material with coating rubber, and has a cord angle of 0° or more and 10° or less in absolute value. Also, the belt cover 143 is, for example, a strip material formed by coating one or a plurality of belt cover cords with coating rubber, and this strip material is wound around the outer peripheral surfaces of the intersecting belts 141 and 142 a plurality of times in a spiral shape in the tire circumferential direction. Further, the belt cover 143 is arranged to cover the entire area of the intersecting belts 141 and 142.

[0018] The tread rubber 15 is arranged on the outer periphery in the tire radial direction of the carcass layer 13 and the belt layer 14 to form the tread portion of the tire 1. Also, the tread rubber 15 is made of a rubber material excellent in grounding characteristics and weather resistance, and is exposed over the entire area of the tire outer peripheral surface to form the tread surface. The pair of sidewall rubbers 16 and 16 are respectively arranged on the outer sides in the tire width direction of the carcass layer 13 to form the left and right sidewall portions. The pair of rim cushion rubbers 17 and 17 extend from the inner side in the tire radial direction to the outer side in the tire width direction of the left and right bead cores 11 and 11 and the turned-back portion of the carcass layer 13 to form the rim fitting surface of the bead portion.

[0019] [Tire side portion] FIG. 2 is a plan view showing the tire side portion of the tire described in FIG. 1. FIG. 3 is an enlarged view showing the emblem portion 2 of the tire side portion described in FIG. 2. In these figures, FIG. 2 shows a plan view of the tire 1 viewed from the axial direction, and FIG. 3 shows a part of the emblem portion 2.

[0020] As shown in FIG. 2, the tire 1 includes an emblem portion 2 and a peripheral region 3 in the tire side portion.

[0021] The emblem portion 2 includes an emblem composed of characters, figures or symbols, or a combination thereof, and in particular includes a trademark that functions as an identification mark indicating a tire manufacturer, a tire brand, etc. Also, a plurality of emblem portions 2, 2 are arranged at intervals in the tire circumferential direction. For example, in the configuration of FIG. 2, an emblem composed of a combination of the character string "YOKOHAMA" indicating the tire manufacturer and a logo in which the first letter "Y" is designed is engraved on the surface of the tire side portion. Also, a pair of emblem portions 2, 2 are arranged at opposing positions in the tire circumferential direction.

[0022] Also, in FIG. 3, the radial height H2 of the elements 21A to 21E constituting the emblem portion 2 is in the range of 0.05 ≦ H2 / SH ≦ 0.80 with respect to the tire section height SH, preferably in the range of 0.10 ≦ H2 / SH ≦ 0.70. Thereby, the visibility of the emblem portion 2 is improved.

[0023] The radial height H2 of the elements 21A to 21E is measured as the maximum value of the extension length of the elements 21A to 21E in the tire radial direction.

[0024] The tire section height SH is a distance that is half of the difference between the tire outer diameter and the rim diameter, and is measured with the tire mounted on a specified rim and applying a specified internal pressure and in an unloaded state.

[0025] The specified rim refers to the "Applicable Rim" defined by JATMA, the "Design Rim" defined by TRA, or the "Measuring Rim" defined by ETRTO. The specified internal pressure refers to the "Maximum Air Pressure" defined by JATMA, the maximum value of "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" defined by TRA, or the "INFLATION PRESSURES" defined by ETRTO. The specified load refers to the "Maximum Load Capacity" defined by JATMA, the maximum value of "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" defined by TRA, or the "LOAD CAPACITY" defined by ETRTO. However, in the case of passenger car tires in JATMA, the specified internal pressure is 180 [kPa] of air pressure, and the specified load is 88 [%] of the maximum load capacity.

[0026] The peripheral region 3 is a region surrounding the emblem portion 2 and is formed on the surface of the tire side portion. This peripheral region 3 may be a smooth surface having a smooth surface, or may be an uneven surface with surface treatment.

[0027] For example, in the configuration of FIG. 2, the peripheral region 3 is a smooth surface and has a continuous smooth surface without grooves or uneven portions. Further, since the peripheral region 3 is arranged to surround the entire emblem portion 2, the visibility of the emblem portion 2 is enhanced. Further, since the peripheral region 3 is formed between a pair of thin ribs 41 and 42 extending in the tire circumferential direction, the designability of the tire side portion is enhanced. Further, since the single peripheral region 3 has an annular structure extending over the entire circumference of the tire side portion, it surrounds the pair of emblem portions 2, 2.

[0028] In addition, in the configuration of FIG. 2, the logo portion 2 and the peripheral region 3 are arranged on the radially outer side of the tire with respect to the maximum tire width position Ac. More specifically, in the region from the tire ground contact end T to the maximum tire width position Ac (see FIG. 1), a pair of thin ribs 41, 42 extending in the tire circumferential direction are arranged, and the logo portion 2 and the peripheral region 3 are arranged between these thin ribs 41, 42. Thereby, the visibility of the logo portion 2 is enhanced. However, not limited to this, the logo portion 2 and the peripheral region 3 may be arranged to intersect the maximum tire width position Ac, or may be arranged on the radially inner side of the tire with respect to the maximum tire width position Ac (not shown).

[0029] The maximum tire width position Ac is defined as the maximum width position of the tire cross-sectional width.

[0030] The tire cross-sectional width is measured as the straight-line distance between the sidewalls excluding patterns, characters, etc. on the tire side surface when the tire is mounted on a specified rim, a specified internal pressure is applied, and the tire is in an unloaded state.

[0031] The tire ground contact end T is defined as the maximum width position in the tire axial direction on the contact surface between the tire and the flat plate when the tire is mounted on a specified rim, a specified internal pressure is applied, and a load corresponding to a specified load is applied while the tire is placed perpendicular to the flat plate in a stationary state.

[0032] Note that the pair of thin ribs 41, 42 described above have a width of 0.4 [mm] or more and 0.8 [mm] or less and a height of 0.1 [mm] or more and 1.0 [mm] or less, and function as a discharge path for residual air during tire vulcanization molding. Thereby, the occurrence of vulcanization failure in the logo portion 2 and the peripheral region 3 is suppressed. Also, in the configuration of FIG. 2, the thin rib 41 on the outer diameter side is at the split position of the mold of the tire molding die.

[0033] Also, in FIG. 3, the radial height H2 [mm] of the elements 21A to 21E constituting the emblem portion 2 is in the range of 0.30 ≦ H2 / H4 ≦ 0.80 with respect to the arrangement interval H4 [mm] of the thin ribs 41 and 42 in the tire radial direction, and preferably in the range of 0.40 ≦ H2 / H4 ≦ 0.70. Further, as shown in FIG. 3, it is preferable that the emblem portion 2 is arranged apart from the pair of thin ribs 41 and 42. Thereby, the visibility of the emblem portion 2 is enhanced.

[0034] [Ridge of emblem portion] FIGS. 4 to 6 are explanatory views showing the emblem portion 2 of the tire side portion described in FIG. 2. In these figures, FIG. 4 shows one element 2A constituting the emblem portion 2, FIG. 5 is an enlarged perspective view showing a part of the emblem portion 2 described in FIG. 4, and FIG. 6 is a cross-sectional view taken along line A showing the emblem portion 2 described in FIG. 5.

[0035] As shown in FIGS. 4 to 6, the emblem portion 2 is composed of a housing 21 and a plurality of ridges 22. Here, as an example, the logo 2A constituting the emblem portion 2 will be described.

[0036] The housing 21 is a frame-shaped recess formed on the tire side surface, and forms the contour line of the emblem portion 2 in a plan view of the tire side portion. Further, the depth H21 (see FIG. 6) of the housing 21 is in the range of 0.10 [mm] ≦ H21 ≦ 3.00 [mm], and preferably in the range of 0.20 [mm] ≦ H21 ≦ 1.50 [mm].

[0037] The depth H21 of the housing 21 is defined as the distance from the edge portion of the housing 21 (in FIG. 6, the surface of the peripheral region 3 surrounding the emblem portion 2) to the bottom surface of the housing 21, and specifically, it is measured as the distance from the edge portion of the housing 21 to the bottom of the valley between the adjacent ridges 22 and 22.

[0038] As shown in FIG. 5, the ridge 22 is a rib-shaped convex portion protruding from the bottom surface of the housing 21, and has a cross-sectional shape in which the width W22 (see FIG. 6) is narrowed toward the top. Further, the plurality of ridges 22 are arranged in parallel in a predetermined direction and filled in the housing 21.

[0039] For example, in the configuration of FIG. 2, as shown in FIG. 4, the logo 2A constituting the logo portion 2 is composed of a combination of a plurality of parallel thin lines. As shown in FIG. 5, the contour lines of these thin lines are formed by the edge portion of the housing 21. Similarly, other components constituting the logo portion 2 (for example, elements 2B to 2E in FIG. 3) are composed of thick lines indicating characters, and the contour lines of the thick lines are formed by the edge portion of the housing 21 (not shown).

[0040] Also, as shown in FIG. 5, the plurality of ridges 22 have a straight shape with a trapezoidal or triangular uniform cross-section. Further, these ridges 22 are arranged with their longitudinal directions aligned in one direction and are filled over the entire area of the housing 21. Also, both ends of the ridge 22 are connected to the wall surface of the housing 21. Thereby, the logo of the logo portion 2 is presented by the housing 21 and the plurality of ridges 22.

[0041] In the above configuration, since the logo portion 2 is composed of a plurality of ridges 22 arranged in the housing 21, (1) in a plan view of the tire side portion, the light absorption rate in the logo portion 2 becomes relatively larger than the light absorption rate in the peripheral region 3. Thereby, the logo portion 2 is relatively blackened, and the visibility of the logo portion 2 is improved. Also, (2) since the wax applied to the logo portion 2 is held by the plurality of ridges 22, the wax holding property in the logo portion 2 is improved.

[0042] Also, in Fig. 6, the height H22 of the ridge 22 is in the range of 1.00 ≦ H22 / H21 with respect to the depth H21 of the housing 21. Therefore, the top of the ridge 22 is exposed on the surface of the peripheral region 3 without being buried in the housing 21. As a result, wax is easily applied to the top of the ridge 22, and the wax retention in the emblem portion 2 is further improved. Also, the height H22 of the ridge 22 is in the range of 0 [mm] ≦ H22 - H21 ≦ 3.50 [mm], preferably 0.10 [mm] ≦ H22 - H21 ≦ 1.50 [mm], and more preferably 0.20 [mm] ≦ H22 - H21 ≦ 1.00 [mm] with respect to the depth H21 of the housing 21. The lower limit ensures the wax retention in the emblem portion 2, and the upper limit suppresses the deterioration of the air resistance of the tire side portion due to the ridge height H22 being too large.

[0043] As shown in Fig. 6, the height H22 of the ridge 22 is defined as the distance from the top of the ridge 22 to the bottom surface of the housing 21, and specifically, it is measured as the distance from the top of the ridge 22 to the bottom of the valley between adjacent ridges 22, 22.

[0044] Also, in Fig. 6, the pitch length P22 of the plurality of ridges 22 is in the range of 0.05 [mm] ≦ P22 ≦ 0.50 [mm], preferably 0.05 [mm] ≦ P22 ≦ 0.30 [mm]. Therefore, the plurality of ridges 22 are densely arranged. As a result, the blackening effect of the emblem portion 2 by the ridge 22 is improved.

[0045] Also, in FIG. 6, the width W22A at the top of the ridge 22 is in the range of 0 ≦ W22A / W22B ≦ 0.90 with respect to the width W22B at the base of the ridge 22, preferably in the range of 0.10 ≦ W22A / W22B ≦ 0.70. The lower limit suppresses the deterioration of the workability of the marking portion 2 due to the top of the ridge 22 being too thin, and the upper limit improves the blackening effect of the marking portion 2 by the ridge 22. Further, the width W22B at the base of the ridge 22 is in the range of 0.05 ≦ W22B / P22 ≦ 0.80 with respect to the pitch length P22 of the plurality of ridges 22, preferably in the range of 0.05 ≦ W22B / P22 ≦ 0.50.

[0046] The widths W22A and W22B of the ridge 22 are measured as the widths in a cross-section perpendicular to the longitudinal direction of the ridge 22. Further, the width W22B at the base of the ridge 22 is defined as the width of the contact portion between the ridge 22 and the bottom surface of the housing 21, and specifically, it is measured as the distance of an imaginary line connecting the bottoms of the valleys between adjacent ridges 22, 22.

[0047] [Modification Example] FIGS. 7 to 9 are explanatory views showing modification examples of the tire 1 described in FIG. 6. In these figures, the same components as those described in FIG. 6 are denoted by the same reference numerals, and the description thereof is omitted.

[0048] In the configuration of FIG. 6, the plurality of ridges 22 have a trapezoidal cross-section in a cross-sectional view perpendicular to the longitudinal direction. Therefore, the top of the ridge 22 has a wide top surface. Such a configuration is preferable in terms of easy processing of the ridge 22.

[0049] On the other hand, in the configuration of FIG. 7, the plurality of ridges 22 have a triangular cross-section in a cross-sectional view perpendicular to the longitudinal direction. Therefore, the top of the ridge 22 has a very narrow width W22A. Such a configuration is preferable in terms of improving the blackening effect of the marking portion 2 by the ridge 22.

[0050] In addition, in the configuration of Fig. 6, the top of the ridge 22 protrudes outside the housing 21. Therefore, the height H22 of the ridge 22 is in the range of 0 [mm] < H22 - H21 with respect to the depth H21 of the housing 21. Such a configuration is preferable in that the wax holding effect by the ridge 22 is enhanced.

[0051] On the other hand, in the configuration of Fig. 8, the height H22 of the ridge 22 is set such that the top surface of the ridge 22 is flush with the surface of the peripheral region 3. Therefore, the height H22 of the ridge 22 has a relationship of H22 - H21 = 0 [mm] with respect to the depth H21 of the housing 21. Even with such a configuration, the wax holding effect by the ridge 22 is enhanced as compared with the configuration in which the top of the ridge 22 is buried in the housing 21 (H22 - H21 < 0 [mm]).

[0052] Also, in the configuration of Fig. 6, the peripheral region 3 is a smooth surface having a smooth surface. Such a configuration is preferable in that the visibility of the emblem portion 2 composed of the housing 21 and the plurality of ridges 22 is improved.

[0053] However, not limited to this, as shown in Fig. 9, the peripheral region 3 may be a concavo-convex surface having a surface treatment. The concavo-convex surface having a surface treatment may be configured by arranging a plurality of arranged concavo-convex portions, for example, a plurality of ridges or a plurality of grooves having a longitudinal shape, or may be configured by arranging a plurality of protrusions or a plurality of depressions having a hemispherical shape or a conical shape (not shown). Thereby, the wax holding property in the emblem portion 2 and the peripheral region 3 is improved.

[0054] In addition, in the configuration of FIG. 9, the uneven surface of the peripheral region 3 is formed by arranging a plurality of uneven portions 31 and 32. Further, the pitch length P3 of the plurality of uneven portions 31 and 32 is in the range of 0.20 ≦ P3 / P22 ≦ 5.00 with respect to the pitch length P22 of the plurality of ridges 22 constituting the emblem portion 2, and preferably in the range of 0.30 ≦ P3 / P22 ≦ 3.00. Further, the height H3 of the plurality of uneven portions 31 and 32 is in the range of 0.30 ≦ H3 / H22 ≦ 1.00 with respect to the height H22 of the plurality of ridges 22 constituting the emblem portion 2, and preferably in the range of 0.50 ≦ H3 / H22 ≦ 0.80. Therefore, the pitch length P3 of the plurality of uneven portions 31 and 32 is shorter than the pitch length P22 of the plurality of ridges 22 constituting the emblem portion 2. Further, the height H3 of the plurality of uneven portions 31 and 32 is smaller than the height H22 of the plurality of ridges 22 constituting the emblem portion 2. As a result, the visibility of the emblem portion 2 is improved.

[0055] [Applicable Object] In this embodiment, as described above, a pneumatic tire has been described as an example of the tire. However, the present invention is not limited to this, and the configuration described in this embodiment can be arbitrarily applied to other tires within the scope obvious to those skilled in the art. Examples of other tires include, for example, airless tires and solid tires.

[0056] [Effect] As described above, [1] this tire 1 includes an emblem portion 2 formed on the tire side surface (see FIGS. 1 and 2). Further, the emblem portion 2 is composed of a housing 21 formed on the tire side surface and a plurality of ridges 22 protruding from the bottom surface of the housing 21 and arranged in parallel in a predetermined direction (see FIGS. 5 and 6). Further, the height H22 of the ridge 22 is in the range of 1.00 ≦ H22 / H21 with respect to the depth H21 of the housing 21 (see FIG. 6). Further, the pitch length P22 of the plurality of ridges 22 is in the range of 0.05 [mm] ≦ P22 ≦ 0.50 [mm].

[0057] In such a configuration, (1) since the logo portion 2 is composed of a plurality of ridges 22 arranged in the housing 21, the logo portion 2 is blackened in a plan view of the tire side portion, improving the visibility of the logo portion 2 and also improving the retention of the wax applied to the logo portion 2. Further, (2) since the height H22 of the ridge 22 is within the above range with respect to the depth H21 of the housing 21, wax is easily applied to the top of the ridge 22, further improving the retention of the wax in the logo portion 2. Furthermore, (3) since the pitch length P22 of the plurality of ridges 22 is within the above range, the blackening effect of the logo portion 2 by the ridges 22 is improved. As a result, there is an advantage in that the visibility of the logo portion 2 and the retention of the wax are improved.

[0058] Also, [2] this tire 1 is the tire 1 described in [1] above, wherein the height H22 of the ridge 22 is in the range of 0 [mm] ≦ H22 - H21 ≦ 3.50 [mm] with respect to the depth H21 of the housing 21 (see FIG. 6). By the above lower limit, the retention of the wax in the logo portion 2 is ensured, and by the above upper limit, there is an advantage in that the deterioration of the air resistance of the tire side portion due to the ridge height H22 being too large is suppressed.

[0059] Also, [3] this tire 1 is the tire 1 described in [1] or [2] above, wherein the height H22 of the ridge 22 (see FIG. 6) is in the range of 0.10 [mm] ≦ H22 - H21 with respect to the depth H21 of the housing 21. In such a configuration, since the ridge 22 of the logo portion 2 protrudes from the housing 21 to the outside, there is an advantage in that the retention of the wax in the logo portion 2 is improved.

[0060] Also, [4] this tire 1 is the tire 1 described in any one of [1] to [3] above, wherein the depth H21 of the housing 21 (see FIG. 6) is in the range of 0.10 [mm] ≦ H21 ≦ 3.00 [mm]. By the above lower limit, the depth H21 of the housing 21 is ensured, and the improvement effect of the visibility and the wax retention in the logo portion 2 is ensured. By the above upper limit, there is an advantage in that the deterioration of the workability of the logo portion 2 due to the depth H21 of the housing 21 being too deep is suppressed.

[0061] Further, [5] in the tire 1 described in any one of [1] to [4] above, the width W22A at the top of the ridge 22 is in the range of 0 < W22A / W22B ≦ 0.90 with respect to the width W22B at the base of the ridge 22 (see Fig. 6). Due to the above lower limit, deterioration of the workability of the emblem portion 2 caused by the top of the ridge 22 being too thin is suppressed, and due to the above upper limit, there is a viewpoint that the blackening effect of the emblem portion 2 by the ridge 22 is improved.

[0062] Further, [6] in the tire 1 described in any one of [1] to [5] above, the peripheral region 3 surrounding the emblem portion 2 is a smooth surface having a smooth surface (see Figs. 2 and 3). Thereby, there is an advantage that the visibility of the emblem portion 2 is improved.

[0063] Further, [7] in the tire 1 described in any one of [1] to [5] above, the peripheral region 3 surrounding the emblem portion 2 is a concavo-convex surface having a surface finish (see Fig. 9). Thereby, there is an advantage that the wax holding property in the emblem portion 2 and the peripheral region 3 is improved.

[0064] Further, [8] in the tire 1 described in [7] above, the concavo-convex surface of the peripheral region 3 is formed by arranging a plurality of concavo-convex portions 31, 32 (see Fig. 9). Also, the pitch length P3 of the plurality of concavo-convex portions 31, 32 is shorter than the pitch length P22 of the plurality of ridges 22 constituting the emblem portion 2 (P3 < P22). Thereby, there is an advantage that the visibility of the emblem portion 2 with respect to the peripheral region 3 is improved.

[0065] Further, [9] in the tire 1 described in [7] or [8] above, the concavo-convex surface of the peripheral region 3 is formed by arranging a plurality of concavo-convex portions 31, 32 (see Fig. 9). Also, the height P3 of the plurality of concavo-convex portions 31, 32 is smaller than the height H22 of the plurality of ridges 22 constituting the emblem portion 2 (H3 < H22). Thereby, there is an advantage that the visibility of the emblem portion 2 with respect to the peripheral region 3 is improved.

Example

[0066] FIG. 10 is a chart showing the results of the performance test of the tire according to the embodiment of the present invention.

[0067] In this performance test, for a plurality of types of test tires, evaluations were made on (1) the visibility performance of the logo part and (2) the wax retention performance. Further, a test tire of tire size 235 / 50R18 was assembled to a rim of rim size 18×71 / 2J, and an internal pressure of 230 [kPa] was applied to this test tire.

[0068] (1) In the evaluation regarding the visibility performance of the logo part, an inspector visually observes the tire side part of the test tire from a distance of 5 [m] and performs a sensory evaluation on the visibility of the logo part, particularly the degree of blackening of the logo part. This evaluation is performed by index evaluation with a comparative example as a reference (100), and the larger the numerical value, the more preferable.

[0069] (2) In the evaluation regarding the wax retention performance, an aqueous tire wax containing a red coloring agent is applied to the tire side part of the test tire, and the test tire is exposed in an outdoor exposure test site. Then, after one month has passed, an inspector visually evaluates the residual degree of the wax in the logo part. This evaluation is performed by index evaluation with a comparative example as a reference (100), and the larger the numerical value, the more preferable.

[0070] The test tires of the examples and the comparative examples have the configurations of FIGS. 1 and 2, and the logo part 2 is composed of a housing 21 and a plurality of ridges 22 (see FIGS. 5 and 6). Further, the peripheral region 3 surrounding the logo part 2 is composed of a smooth surface, and the logo part 2 and the peripheral region 3 are arranged between a pair of thin ribs 41 and 42. Further, the radial height H2 [mm] of the logo part 2 is 18 [mm], and the arrangement interval H4 [mm] of the thin ribs 41 and 42 is 25.5 [mm].

[0071] As shown by the test results, it can be seen that in the test tires of the examples, the visibility performance of the logo part and the wax retention performance are improved.

Explanation of Reference Numerals

[0072] 1 Tire; 11 Bead core; 12 Bead filler; 13 Carcass layer; 14 Belt layer; 141, 142 Cross belt; 143 Belt cover; 15 Tread rubber; 16 Sidewall rubber; 17 Rim cushion rubber; 20 Rim; 2 Marking portion; 21 Housing; 22 Ridge; 3 Peripheral region; 31 Concave-convex portion; 41, 42 Thin ribs

Claims

1. A tire having a logo portion formed on a tire side surface, wherein the logo portion is composed of a housing formed on the tire side surface and a plurality of ridges protruding from the bottom surface of the housing and arranged in parallel in a predetermined direction, wherein a height H22 of the ridge satisfies 1.00 ≦ H22 / H21 with respect to a depth H21 of the housing, and wherein a pitch length P22 of the plurality of ridges is in a range of 0.05 [mm] ≦ P22 ≦ 0.50 [mm]. The tire is characterized by this.

2. The tire according to claim 1, wherein the height H22 of the ridge satisfies 0 [mm] ≦ H22 - H21 ≦ 3.50 [mm] with respect to the depth H21 of the housing.

3. The tire according to claim 2, wherein the height H22 of the ridge satisfies 0.10 [mm] ≦ H22 - H21 with respect to the depth H21 of the housing.

4. The tire according to claim 1, wherein the depth H21 of the housing satisfies 0.10 [mm] ≦ H21 ≦ 3.00 [mm].

5. The tire according to claim 1, wherein a width W22A of a top portion of the ridge satisfies 0 < W22A / W22B ≦ 0.90 with respect to a width W22B of a base portion of the ridge.

6. The tire according to claim 1, wherein a peripheral region surrounding the logo portion is a smooth surface having a smooth surface.

7. The tire according to claim 1, wherein a peripheral region surrounding the logo portion is a concavo-convex surface having a surface treatment.

8. The tire according to claim 7, wherein the concavo-convex surface of the peripheral region is formed by arranging a plurality of concavo-convex portions, and a pitch length P3 of the plurality of concavo-convex portions is shorter than a pitch length P22 of the plurality of ridges constituting the logo portion.

9. The tire according to claim 7, wherein the concavo-convex surface of the peripheral region is formed by arranging a plurality of concavo-convex portions, and a height P3 of the plurality of concavo-convex portions is smaller than a height H22 of the plurality of ridges constituting the logo portion.

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