Tire

Abstract

Provided is a tire in which the black density is further improved compared to conventional tires and the contrast ratio is increased. A portion of an outer surface (3a) of a sidewall (3) is provided with a pattern region (7) provided in a state of being visible as a site different from the surrounding, and a plurality of protrusions (20) are disposed in the pattern region, each protrusion including a bottom surface (21), a tip section (22) farthest from the bottom surface, and a main body section (30) connecting the bottom surface and the tip section. A protrusion provided between the bottom surface and the tip portion, the protrusion having a cross-section larger than the equivalent circle diameter of the bottom surface and having the maximum equivalent circle diameter in the protrusion; a bottom-surface-side main body section (32) provided from the expanded section to the bottom surface, the area of the cross-section of the bottom-surface-side main body section gradually decreasing from the expanded section toward the bottom surface; and a tip-side main body section (31) which is provided from the expanded section to the tip section (22), and which has a cross-sectional area that gradually decreases from the expanded section (23) toward the tip section (22).

Description

Technical Field

[0001] The present invention relates to a tire having a pattern area for displaying, for example, a logo, a tread pattern, etc. on a part of the outer surface of the sidewall. Background Art

[0002] Conventionally, a tire having a pattern area formed by a plurality of fine protrusions provided on a part of the sidewall of a tire (for example, Patent Document 1 etc.) has been known. In such a pattern area, the incident light is repeatedly reflected between the protrusions to produce a light absorption effect, whereby it is visually recognized as darker than the outer surface of the surrounding sidewall, and the contrast is improved. By providing such a pattern area, the tire can achieve, for example, an improved design effect and appearance.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2017-1440 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] The high contrast achieved by a plurality of protrusions is less likely to undergo secular changes compared to methods such as painting, and has the advantage of maintaining its effect for a long time. Therefore, it is desired to further increase the black density compared to the prior art and promote high contrast, and to form a pattern area based on protrusions that further improves the design effect and appearance.

[0008] An object of the present invention is to provide a tire that achieves a higher contrast with a further increase in black density compared to the prior art.

[0009] Means for Solving the Problems

[0010] The tire of the present invention has a pattern area on a part of the outer surface of the sidewall, the pattern area being provided in a state where it can be visually recognized as a part different from the surrounding part. Among them, a plurality of protrusions protruding from the surface of the pattern area are arranged in the pattern area. Each of the plurality of protrusions includes a bottom surface integral with the surface of the pattern area, a tip end portion farthest from the bottom surface, and a main body portion connecting the bottom surface and the tip end portion. The main body portion has: a bulged portion provided between the bottom surface and the tip end portion, having a cross-section with a larger equivalent circle diameter than that of the bottom surface and the largest equivalent circle diameter among the protrusions; a bottom surface side main body portion provided from the bulged portion to the bottom surface, the cross-sectional area of which gradually decreases as it goes from the bulged portion toward the bottom surface; and a tip end portion side main body portion provided from the bulged portion to the tip end portion, the cross-sectional area of which gradually decreases as it goes from the bulged portion toward the tip end portion.

[0011] Advantages of the Invention

[0012] According to the present invention, a tire can be provided which has a further increased black density compared with the prior art, thereby achieving a higher contrast ratio. Description of the Drawings

[0013] Figure 1 It is a side view of the tire of the embodiment.

[0014] Figure 2 It is a cross-sectional view showing an example of a forming die for vulcanizing and forming the tire of the embodiment.

[0015] Figure 3 It is a perspective view showing a state in which a plurality of protrusions are arranged in a pattern area of the tire of the embodiment.

[0016] Figure 4 It is Figure 3 a view taken in the direction of IV of

[0017] Figure 5 It is a plan view showing another example of the arrangement pattern of the plurality of protrusions arranged in the above-mentioned pattern area.

[0018] Figure 6 It is a perspective view of the protrusion of the embodiment.

[0019] Figure 7 It is a side view of a pair of adjacent protrusions of the embodiment.

[0020] Figure 8 It is a side view of a pair of adjacent protrusions of the embodiment, and is a view schematically showing the light absorption effect of these protrusions.

[0021] Description of Reference Numerals

[0022] 1 Tire

[0023] 3 Sidewall

[0024] 3a Outer surface of the sidewall

[0025] 7 Pattern area

[0026] 7a Surface of the pattern area

[0027] 20 Protrusion

[0028] 21 Bottom surface

[0029] 22 Tip portion

[0030] 23 Bulging portion

[0031] 30 Main body portion

[0032] 31 Tip portion side main body portion

[0033] 32 Bottom side main body portion. DETAILED DESCRIPTION

[0034] Hereinafter, the embodiments will be described with reference to the drawings. It should be noted that the term "substantially" in this specification does not mean that the state is strictly determined, but includes an approximate state within a range in which the functions and effects can be achieved.

[0035] Figure 1 1 is a side view of a tire 1 according to an embodiment. The tire 1 is a so-called pneumatic tire whose inner cavity is filled with a predetermined air pressure. The tire 1 according to the embodiment is a pneumatic tire for passenger vehicles including light vehicles, SUVs, etc. It should be noted that the structure of the tire 1 according to the embodiment can also be applied to pneumatic tires for other types of vehicles such as light trucks, trucks, and buses.

[0036] First, refer to Figure 1 The outline of the structure of the tire 1 mainly related to the side faces will be described. Figure 1 This is a side view of the tire 1 viewed from the direction of the tire rotation axis X. It should be noted that the tire axial direction, tire circumferential direction, and tire radial direction mentioned in the following description are as follows. The tire axial direction refers to the extension direction of the tire rotation axis X. Figure 1 The tire circumferential direction refers to the circular arc with the tire rotation axis X as the center, which is the direction along the rotation direction of the tire 1. Figure 1 The radial direction of the tire refers to the direction perpendicular to the tire rotation axis X. Figure 1 It is arbitrarily indicated by arrow Y.

[0037] like Figure 1 As shown in FIG. 1 , the tire 1 includes a bead 2, a sidewall 3 extending from the bead 2 in the tire radial direction to the outer side of the tire radial direction away from the tire rotation axis X, and a tread 4. The bead 2 and the sidewall 3 are respectively Figure 1 The side 1s of the tire 1 shown is separated from the side 1s of the tire 1 in the axial direction. Figure 1 The other side surface not shown in the figure is provided with one on each side, that is, a pair of left and right treads. The tread 4 is arranged between the radially outer sides of the left and right sidewalls 3. The outer peripheral surface of the tread 4 includes a tread surface that contacts the road surface.

[0038] The tire 1 is configured with various rubbers that respectively constitute the bead 2, the sidewall 3, and the tread 4 as the main body. Inside the cavity side of the rubber that constitutes the entire tire 1, a carcass ply that constitutes the skeleton of the tire 1 is disposed, and further, an airtight layer that maintains the air pressure is disposed on the cavity side of the carcass ply. In addition, an annular reinforcing belt layer (the carcass ply, the airtight layer, and the reinforcing belt layer are omitted from illustration) is embedded inside the rubber that constitutes the tread 4. It should be noted that, in addition to these components, various components are also provided as needed for the functions of the tire 1.

[0039] As Figure 1 shown, the sidewall 3 has an annular decorative area 5 on its outer surface 3a that extends over the entire tire circumference. The decorative area 5 is a region with a constant width that is sandwiched between an inner arc line 5a on the tire radial inner side that is closer to the tire rotation axis X in the tire radial direction and an outer arc line 5b that is on the tire radial outer side relative to the inner arc line 5a. The inner arc line 5a and the outer arc line 5b can be lines formed by concave, convex, or stepped portions on the outer surface 3a of the sidewall 3, or they can be imaginary lines that do not actually exist.

[0040] The tire radial position of the decorative area 5 on the outer surface 3a of the sidewall 3 can be located at a position on the tire radial outer side relative to the position of the maximum tire width, or it can be located at a position that includes the position of the maximum tire width. It should be noted that the position of the maximum tire width refers to the position where the tire axial length is the longest between the outer surfaces 3a of the left and right sidewalls 3.

[0041] The tire 1 has a pattern area 7 on a part of the outer surface 3a of the sidewall 3, and the pattern area 7 is set to be visually recognizable as a part different from the surrounding area of this part. The pattern area 7 is provided on the sidewall rubber, which is a black rubber member that constitutes the outer surface 3a of the sidewall 3.

[0042] As Figure 1 shown, at two positions on the annular decorative area 5 that are opposed across the tire rotation axis X, there are provided emblem portions 6A. The emblem portions 6A are formed by arranging a plurality of characters along the tire circumference. Through these plurality of characters, at least one of emblems such as the manufacturer name, product name, brand, etc. is displayed. Each character can be formed by being bordered with concave or convex lines, or the entire character can be formed by being concave or convex. For example, each character of the emblem portion 6A is set as the pattern area 7 of the embodiment.

[0043] As Figure 1 shown, in the annular decorative area 5, at two positions that are sandwiched by the two emblem portions 6A in the circumferential direction, there are provided tread pattern portions 6B. In the tread pattern portions 6B, there are provided tread patterns in which parallelograms are curved following the annular decorative area 5. For example, each tread pattern of the tread pattern portions 6B is also set as the pattern area 7 of the embodiment.

[0044] It should be noted that the shape of the pattern area 7 is not limited to this, and various shapes can be cited, such as any shape, or the shape depicting the above-mentioned maker's name, product name, brand, etc. marks, or the shape depicting other numbers, characters, etc.

[0045] Each of the above-mentioned pattern areas 7 in the embodiment has a surface 7a along the contour of the sidewall 3. A plurality of protrusions 20 described later are formed on this surface 7a. The pattern area 7 is an area that is set to be visually recognizable as a part different from the periphery of the pattern area 7 by forming a plurality of protrusions 20.

[0046] Figure 2 An example of a tire forming die for vulcanizing and forming the tire 1 of the embodiment is shown. Figure 2 This is a meridian sectional view of such a tire forming die 10 along the axial direction of the formed tire 1.

[0047] Figure 2 The shown tire forming die 10 includes a plurality of sector dies 11 arranged in a circular shape along the outer peripheral side of the tire 1, a pair of side plates 12 disposed on both axial sides of the annular body formed by the combination of the plurality of sector dies 11, and a pair of bead rings (not shown). During vulcanization and forming, as shown by the dotted line in Figure 2 an unvulcanized tire 1a of the tire 1 is disposed inside the tire forming die 10. The combination of the sector die 11, the side plate 12, and the bead ring is a forming die for forming the tire 1, and the outer surface of the entire tire 1 is formed by the inner surfaces of this forming die, that is, the inner surface 11a of the sector die 11, the inner surface 12a of the side plate 12, and the inner surface of the bead ring. In addition, during vulcanization and forming, an airbag (not shown) that presses the unvulcanized tire 1a against the inner surface of the tire forming die 10 is disposed inside the unvulcanized tire 1a. The tread 4 is mainly formed by the plurality of sector dies 11, and the sidewall 3 is mainly formed by the pair of side plates 12. The bead 2 is formed by the pair of above-mentioned bead rings, and the entire inner surface of the tire 1 is formed by the above-mentioned airbag.

[0048] The unvulcanized tire 1a is vulcanized using the tire forming die 10 to form the rubber shape of the entire tire 1, and a plurality of protrusions 20 described below are formed in the above-mentioned pattern area 7.

[0049] Figure 3 and Figure 4 are diagrams showing the plurality of protrusions 20 disposed in the pattern area 7, Figure 3 is a perspective view, Figure 4 is a top view and is a Figure 3 view in the direction of IV of. The plurality of protrusions 20 are disposed on the surface 7a of the pattern area 7 in a state of filling the entire area of the pattern area 7. It should be noted that hereinafter, the surface 7a of the pattern area 7 is sometimes referred to as the pattern area surface 7a.

[0050] As shown Figure 4 in the figure, a plurality of protrusions 20 are arranged in a vertical and horizontal manner on the surface 7a of the pattern area. In Figure 4 , the plurality of protrusions 20 are arranged in a neat arrangement in a linear and equally spaced manner in the horizontal direction as the left - right direction and in the vertical direction as the up - down direction. It should be noted that Figure 4 the arrangement pattern of the plurality of protrusions 20 shown in the figure is an example and is not limited thereto. For example, as Figure 5 shown in the figure, they may also be arranged in a staggered pattern. That is, in Figure 5 , a row in which a plurality of protrusions 20 are arranged in a linear and equally spaced manner in the left - right direction, and a plurality of such rows are arranged in the up - down direction. In a pair of adjacent rows in the up - down direction, the protrusions 20 on one side are arranged between the protrusions 20 on the other side.

[0051] The protrusions 20 of the embodiment are minute protrusions protruding from the surface 7a of the pattern area. Figure 6 is a perspective view showing a single protrusion 20, Figure 7 and Figure 6 is a side view of a pair of adjacent protrusions 20 on the surface 7a of the pattern area. As Figure 7 shown, the protrusion 20 includes a bottom surface 21, a tip portion 22 farthest from the bottom surface 21, and a main body portion 30 connecting the bottom surface 21 and the tip portion 22. The protrusion 20 of the embodiment has an appearance of a substantially acorn shape according to the shape of the main body portion 30. The bottom surface 21 is a hypothetical surface that is integrally the same surface as the surface 7a of the pattern area.

[0052] The bottom surface 21 of the protrusion 20 of the embodiment is substantially circular. As Figure 7 shown, the central axis 20c of the protrusion 20 connecting the center of the bottom surface 21 and the tip portion 22 is substantially perpendicular to the surface 7a of the pattern area and the bottom surface 21. Therefore, the protrusion 20 stands upright with respect to the surface 7a of the pattern area. As Figure 7 shown, the distance from the bottom surface 21 to the tip portion 22 along the central axis 20c is the height H of the protrusion 20, and this height H is the shortest distance from the bottom surface 21 to the tip portion 22. The shape of the cross - section of the protrusion 20 from the bottom surface 21 to the tip portion 22 has a substantially circular shape within the entire length in the height direction. It should be noted that the cross - section referred to in this specification is a plane substantially perpendicular to the central axis 20c, and this cross - section is substantially parallel to the surface 7a of the pattern area.

[0053] In the embodiment, the main body portion 30 of the protrusion 20 has a bulged portion 23 in the middle of its height direction. The bulged portion 23 is a portion where the cross-section is larger than the equivalent circle diameter of the bottom surface 21 and has the largest equivalent circle diameter in the protrusion 20. In other words, the bulged portion 23 is the portion that bulges most laterally in the main body portion 30. Since the cross-section of the protrusion 20 in the embodiment is generally circular, the above-mentioned equivalent circle diameter is the diameter. It should be noted that in the present disclosure, the cross-sectional shape of the protrusion 20 is not limited to a perfect circle, and can also be, for example, an elliptical shape, a triangular shape, a polygonal shape, etc. In the cross-sections in these cases, the equivalent circle diameter is applied.

[0054] The main body portion 30 of the protrusion 20 in the embodiment has a bottom surface side main body portion 32 and a top end portion side main body portion 31 with the bulged portion 23 as the boundary. Figure 6 and Figure 7 In, the bottom surface side main body portion 32 is the portion below the bulged portion 23, that is, the portion from the bulged portion 23 to the bottom surface 21. The area of the cross-section of the bottom surface side main body portion 32 gradually decreases as it goes from the bulged portion 23 towards the bottom surface 21. Figure 6 and Figure 7 In, the top end portion side main body portion 31 is the portion above the bulged portion 23, that is, the portion from the bulged portion 23 to the top end portion 22. The area of the cross-section of the top end portion side main body portion 31 gradually decreases as it goes from the bulged portion 23 towards the top end portion 22. That is, the bottom surface side main body portion 32 has a shape that tapers towards the bottom surface 21 side, and the top end portion side main body portion 31 has a shape that tapers towards the top end portion 22 side.

[0055] The top end portion side main body portion 31 converges from the bulged portion 23 towards the top end portion 22, and the top end portion 22 of the protrusion 20 is formed into a sharp shape with a tapered top. It should be noted that the shape of the top end portion 22 is not limited to this. For example, it can also be formed into a hemispherical shape, or it can be a shape with a flat portion cut parallel to the cross-section at the top.

[0056] As Figure 3 shown, the plurality of protrusions 20 in the embodiment have substantially uniform shapes and sizes. There are no particular limitations on the dimensions for determining the shape, etc. of the protrusion 20 in the embodiment. For example, the following preferred ranges can be cited.

[0057] The height of the protrusion 20 is preferably 2.0 times or more and 3.0 times or less the diameter of the bottom surface 21 ( Figure 6 and Figure 7 denoted by φB in). Specifically, the height of the protrusion 20 is preferably 0.2 mm or more and 0.8 mm or less.

[0058] The diameter of the cross-section of the bulged portion 23 of the protrusion 20 in the embodiment ( Figure 6 and Figure 7It is preferably 120% or more and 150% or less of the diameter of the bottom surface 21 (represented by φM in Chinese). Specifically, the diameter of the cross-section of the bottom surface 21 is preferably 0.1 mm or more and 0.4 mm or less, for example, and the diameter of the cross-section of the bulged portion 23 is preferably 0.2 mm or more and 0.5 mm or less, for example.

[0059] As Figure 7 shown, the height position of the bulged portion 23 corresponding to the height H of the protrusion 20 of the embodiment is preferably arranged within the range represented by H2 between the height position 15% of the height of the protrusion 20 from the center H1 in the height direction of the protrusion 20 toward the bottom surface 21 side and the height position 15% of the height of the protrusion 20 from the center H1 of the height of the protrusion 20 toward the tip portion 22 side.

[0060] In addition, regarding the arrangement state of the plurality of protrusions 20 on the surface 7a of the pattern area, the plurality of protrusions 20 are preferably arranged at a density of two or more within 1 mm 2 In addition, as Figure 7 shown, the closest interval P between the protrusions 20 is preferably 0.5 mm or less, for example.

[0061] The plurality of protrusions 20 of the embodiment arranged on the surface 7a of the pattern area can be formed by the above-mentioned tire forming die 10, for example. In order to form the plurality of protrusions 20 by the tire forming die 10, a plurality of recesses capable of forming these protrusions 20 are formed on the inner surface 12a, which is the tire forming surface of the side plate 12 forming the pattern area 7, corresponding to the protrusions 20.

[0062] In this case, the method for forming the plurality of recesses is not limited, but laser processing in which the inner surface 12a is locally removed by irradiating the inner surface 12a of the side plate 12 with laser is preferably used as the forming method. As the laser processing, for example, removal processing using pulsed fiber laser can be adopted. As the conditions for this laser processing, laser processing with a center wavelength of 1080 nm, an average output of 100 W or more and 300 W or less, and a laser spot diameter of about 0.05 mm is preferred.

[0063] Especially in the case of forming the recesses capable of forming the protrusions 20 of the embodiment in the tire forming die 10 by laser processing, for example, it can be formed by adjusting the output of each pulse or adjusting the irradiation angle of the laser.

[0064] It should be noted that when the protrusion 20 is formed by the tire forming die 10, since the protrusion 20 of the embodiment is a so-called undercut shape, there is sometimes a concern that the protrusion 20 may not fall off from the concave portion where the protrusion 20 is formed during tire demolding. In such a case, by setting the diameter of the enlarged portion 23 to about 150% or less of the diameter of the bottom surface 21, the protrusion 20 can be pulled out smoothly by the elastic deformation of the rubber. Thereby, it is possible to avoid the trouble of dividing the tire forming die 10 or the like in order to demold the protrusion 20.

[0065] In the tire 1 of the embodiment in which a plurality of protrusions 20 are arranged in the pattern area 7 as described above, when light is incident on the pattern area 7, the light is mainly incident on the surface 7a of the pattern area and the main body 30 of the protrusion 20, and is reflected on these surfaces. The reflected light is reflected again by the surrounding protrusions 20 and the surface 7a of the pattern area, and such reflections are repeatedly generated between the plurality of protrusions 20 and between the protrusion 20 and the surface 7a of the pattern area. As a result, the light incident on the pattern area 7 gradually attenuates and is absorbed. When visually recognizing such a pattern area 7, the pattern area 7 is visually recognized as darker than the outer surface 3a of the tire sidewall 3 that reflects the light around the pattern area 7.

[0066] Figure 8 An example of the light absorption effect in the embodiment is schematically shown. When Figure 8 the light shown by L is incident on the surface 7a of the pattern area, the light enters the vicinity of the surface 7a of the pattern area while being reflected in a zigzag manner between the main bodies 30 of a pair of adjacent protrusions 20, and is reflected on the surface 7a of the pattern area. Then, the light reflected on the surface 7a of the pattern area reaches the bottom surface side main body 32 of the main body 30 of the protrusion 20. Here, since the bottom surface side main body 32 is narrowed toward the bottom surface 21 side, the light reflected by the bottom surface side main body 32 is likely to be directed toward the surface 7a side of the pattern area. Therefore, the light reaching the surface 7a of the pattern area is blocked from traveling by the bottom surface side main body 32 of the protrusion 20 and is confined within the pattern area 7, and it is difficult to emit from the pattern area 7 to the outside, that is, it is difficult to be reflected to the outside. Thereby, the light absorption effect of the light incident on the pattern area 7 is promoted, and high contrast with an increase in black density is achieved.

[0067] According to the embodiment described above, the following effects are achieved.

[0068] (1)The tire 1 of the embodiment has a pattern area 7 on a part of the outer surface 3a of the sidewall 3, and the pattern area 7 is provided in a state where it can be visually recognized as a part different from the periphery of this part. Among them, a plurality of protrusions 20 protruding from the surface 7a of the pattern area 7 are arranged in the pattern area 7. The plurality of protrusions 20 include a bottom surface 21 integrated with the surface 7a of the pattern area 7, a tip portion 22 farthest from the bottom surface 21, and a main body portion 30 connecting the bottom surface 21 and the tip portion 22. The main body portion 30 has: a bulged portion 23, which is provided between the bottom surface 21 and the tip portion 22 and has a cross-section with an equivalent circle diameter larger than that of the bottom surface 21 and the largest equivalent circle diameter among the protrusions 20; a bottom surface side main body portion 32, which is provided from the bulged portion 23 to the bottom surface 21 and whose cross-sectional area gradually decreases as it goes from the bulged portion 23 toward the bottom surface 21; and a tip portion side main body portion 31, which is provided from the bulged portion 23 to the tip portion 22 and whose cross-sectional area gradually decreases as it goes from the bulged portion 23 toward the tip portion 22.

[0069] In the tire 1 according to the embodiment, when light is incident on the pattern area 7 where a plurality of protrusions 20 are arranged, the light is mainly incident on the surface 7a of the pattern area and the main body portion 30 of the protrusion 20 and is reflected on these surfaces. The reflected light is reflected again on the surrounding protrusions 20 and the surface 7a of the pattern area, and such reflections are repeatedly generated between the plurality of protrusions 20 and between the protrusion 20 and the surface 7a of the pattern area. As a result, the light incident on the pattern area 7 gradually attenuates and is absorbed. When visually recognizing such a pattern area 7, the pattern area 7 is visually recognized as darker than the outer surface 3a of the sidewall 3 that reflects the light around the pattern area 7. The protrusion 20 of the embodiment has a bottom surface side main body portion 32 whose shape narrows from the bulged portion 23 toward the bottom surface 21. Therefore, through the bottom surface side main body portion 32, the light temporarily entering the pattern area 7 is enclosed within the pattern area 7 and is difficult to be emitted to the outside and is difficult to be reflected to the outside. Therefore, the absorption effect of the light incident on the pattern area 7 is promoted, and the black density of the pattern area 7 is increased compared with the past, realizing high contrast.

[0070] (2)Based on the tire 1 of the above (1) in the embodiment, preferably, the equivalent circle diameter of the cross-section of the bulged portion 23 is 120% or more and 150% or less of the equivalent circle diameter of the bottom surface 21.

[0071] Thereby, the bulged portion 23 with a diameter larger than that of the bottom surface 21 is reliably formed. As a result, the absorption effect of the bottom surface side main body portion 32 on light is promoted. In addition, in the case of forming the protrusion 20 using the concave portion formed in the tire forming die 10 as described above, even in the case of an undercut shape, the protrusion 20 can be demolded.

[0072] (3) Based on the tire 1 in the above (1) and (2) of the embodiment, preferably, the protrusion 20 has a height which is the shortest distance from the bottom surface 21 to the top end portion 22, and the height position of the bulging portion 23 corresponding to the height of the protrusion 20 is arranged between the height position which is 15% of the height of the protrusion 20 from the center in the height direction of the protrusion 20 toward the bottom surface 21 side and the height position which is 15% of the height of the protrusion 20 from the center of the height of the protrusion 20 toward the top end portion 22 side.

[0073] Thus, the height position of the bulging portion 23 in the protrusion 20 is appropriately set to promote the light absorption effect of the main body portion 32 on the bottom surface side.

[0074] (4) Based on the tire 1 in the above (1) to (3) of the embodiment, preferably, the plurality of protrusions 20 are arranged in a linear pattern with a density of two or more within 1 mm 2 inside.

[0075] Thus, the light absorption effect generated between adjacent protrusions 20 is improved, and the black density of the pattern area 7 is increased compared with the prior art, achieving high contrast.

[0076] (5) Based on the tire 1 in the above (1) to (4) of the embodiment, preferably, the plurality of protrusions 20 are arranged in a straight line at equal intervals, and the spacing of the arrangement is 2.0 times or more and 3.0 times or less of the equivalent circle diameter of the bottom surface 21.

[0077] Thus, the light absorption effect generated between adjacent protrusions 20 is improved, and the black density of the pattern area 7 is increased compared with the prior art, achieving high contrast.

[0078] (6) Based on the tire 1 in the above (1) to (5) of the embodiment, preferably, the cross-sectional shape of the protrusion 20 is substantially circular.

[0079] Thus, the light reflected by the protrusion 20 is reflected radially with the protrusion 20 as the center, so the repeated light reflection between the protrusions 20 is likely to be complicated. In addition, there is an effect of confining the light incident on the pattern area 7 within the pattern area 7. As a result, the light absorption effect is improved, and the black density of the pattern area 7 is increased compared with the prior art, achieving high contrast.

[0080] (7) Based on the tire 1 in the above (1) to (6) of the embodiment, preferably, the top end portion 22 has a sharp shape with a tapered top.

[0081] Thus, the light incident on the pattern area 7 is difficult to be reflected at the top end portion of the protrusion 20, and the amount of light reflected to the outside is reduced compared with the case where the shape is not sharp. As a result, high contrast of the pattern area 7 can be achieved.

[0082] As described above, the embodiments of the present invention have been described, but the present invention is not limited to the above embodiments. Even if there are deformations, improvements, etc. within the scope of achieving the object of the present invention, they are also included in the scope of the present invention.

[0083] For example, the plurality of protrusions 20 disposed in the pattern region 7 may not be Figure 4 and Figure 5 the neatly arranged configuration shown, but a random and irregular configuration.

[0084] The protrusions 20 in the above embodiments stand upright on the surface 7a of the pattern region, but they may also be arranged such that the central axis 20c is inclined or tilted with respect to the surface 7a of the pattern region.

[0085] The shapes and sizes of the plurality of protrusions 20 in the above embodiments are substantially uniform, but the shapes and sizes of the respective protrusions 20 may also be non-uniform. For example, the height of the protrusion 20, the diameter of the bottom surface 21, the diameter of the enlarged portion 23, the height position of the enlarged portion 23, etc. may also be different from each other.

Claims

1. A tire comprising a pattern region on a portion of an outer surface of a sidewall, wherein the pattern region is provided in a state where it can be visually recognized as a portion different from the surroundings of the portion, wherein: The pattern region is provided with a plurality of protrusions protruding from a surface of the pattern region, The plurality of protrusions respectively include a bottom surface integral with the surface of the pattern area, a top portion farthest from the bottom surface, and a main body connecting the bottom surface and the top portion. The main body has: an enlarged portion disposed between the bottom surface and the top end portion, having a cross section larger than the equivalent circular diameter of the bottom surface and having the largest equivalent circular diameter among the protrusions; a bottom surface side main body portion, which is provided from the bulged portion to the bottom surface, and whose cross-sectional area gradually decreases from the bulged portion toward the bottom surface; and The distal end portion side main body portion is provided from the bulged portion to the distal end portion, and the cross-sectional area thereof gradually decreases from the bulged portion toward the distal end portion.

2. The tire according to claim 1, wherein: The equivalent circular diameter of the cross section of the enlarged portion is greater than or equal to 120% and less than or equal to 150% of the equivalent circular diameter of the bottom surface.

3. The tire according to claim 1 or 2, wherein: The protrusion has a height which is the shortest distance from the bottom surface to the top end, The height position of the enlarged portion corresponding to the height of the protrusion is configured between a height position that is 15% of the height of the protrusion from the center of the height direction of the protrusion to the bottom side and a height position that is 15% of the height of the protrusion from the center of the height of the protrusion to the top end side.

4. The tire according to claim 1 or 2, wherein: A plurality of said protrusions are within 1 mm in said pattern area. 2 The interior is configured with more than two densities.

5. The tire according to claim 1 or 2, wherein: The plurality of protrusions are arranged in a straight line at equal intervals, and the pitch of the arrangement is not less than 2.0 times and not more than 3.0 times the equivalent circular diameter of the bottom surface.

6. The tire according to claim 1 or 2, wherein: The cross-sectional shape of the protrusion is substantially circular.

7. The tire according to claim 1 or 2, wherein: The tip portion has a sharp shape with a tapered tip.

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