Tire vulcanization mold, tire manufacturing method, and tire

Abstract

To provide a tire vulcanization mold and a method for manufacturing tires in which dirt is less likely to be deposited in recesses arranged on the molding surface.SOLUTION: A tire vulcanization mold 1 includes a molding surface 10 for molding a tire during vulcanization molding, the molding surface 10 including a first region 11 with a plurality of recesses 13 for forming a plurality of projections on the tire surface. The first region 11 has two or more recesses 13 per 1 mm2. Each of the recesses 13 includes a sidewall surface 15, a bottom surface 20, and a hypothetical recess center axis 13c extending in the depth direction of the recess 13. In a cross-sectional view of the recess 13 including the recess center axis 13c, the bottom surface 20 includes a bottom projection 25 that is convex outwardly in the direction of depth. The sidewall surface 15 includes an arcuate surface 16 that is smoothly connected to the bottom surface.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a tire vulcanizing mold, a method for manufacturing a tire, and a tire.

Background Art

[0002] Patent Document 1 below describes a tire having a decorative portion on a part of its outer surface, and a plurality of minute protrusions are arranged on the decorative portion. The decorative portion can reduce the reflection of light by the minute protrusions, and can increase the blackness degree of the decorative portion. Therefore, the contrast between light and dark can be enhanced between the decorative portion and the non-decorative portion adjacent thereto. Thereby, the visibility of the outer surface of the tire is improved.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The tire vulcanizing mold for forming the decorative portion includes a plurality of fine recesses corresponding to the minute protrusions. Such a tire vulcanizing mold is likely to accumulate fine rubber, dust, etc. in the recesses as the tire is repeatedly molded. Therefore, in order to mold while maintaining the blackness degree of the decorative portion, it was necessary to increase the cleaning frequency of the mold.

[0005] The present disclosure has been devised in view of the above actual situation, and the main problem is to provide a tire vulcanizing mold and a method for manufacturing a tire in which dirt hardly accumulates in the recesses arranged on the molding surface.

Means for Solving the Problems

[0006] The present disclosure relates to a tire vulcanization mold, which includes a molding surface for molding a tire during vulcanization molding, and the molding surface includes a first region provided with a plurality of recesses for forming a plurality of protrusions on the tire surface, and the first region includes a plurality of recesses each having a width of 1 mm 2 The tire vulcanizing mold has two or more abutment recesses arranged therein, each of which includes a side wall surface, a bottom surface, and a virtual recess center axis extending in the depth direction of the recess, and in a cross-sectional view of the recess including the recess center axis, the bottom surface includes a bottom protrusion that is convex outward in the depth direction, and the side wall surface includes an arc surface that smoothly connects to the bottom surface. [Effects of the Invention]

[0007] By adopting the above-described configuration, the tire vulcanization mold of the present disclosure is less likely to accumulate dirt in the recesses, thereby suppressing an increase in the frequency of mold cleaning. [Brief explanation of the drawings]

[0008]

Figure 1

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Figure 4

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Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0009] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 shows a cross-sectional view of a tire vulcanizing mold 1 (hereinafter, may be simply referred to as “mold”) of the present embodiment. As shown in FIG. 1, the tire vulcanizing mold 1 of the present embodiment has a molding surface on its inner side for molding the outer surface of an unvulcanized green tire 2. The green tire 2 is heated in the tire vulcanizing mold 1 and is pressed against the molding surface side of the tire vulcanizing mold 1 by an inflated bladder 3 from the inside. Thereby, the green tire 2 is vulcanized and molded to obtain a tire.

[0010] FIG. 2 is a perspective view showing an example of a tire 5 vulcanized and molded by the tire vulcanizing mold 1 of the present disclosure. The tire 5 shown in FIG. 2 is for a passenger car, but the tire vulcanizing mold 1 of the present disclosure is not limited to such a mode, and may be used, for example, for vulcanizing and molding tires for motorcycles or heavy loads.

[0011] As shown in FIG. 2, this tire 5 has a visible outer surface 5s. The visible outer surface 5s is a surface that can be visually observed from the outside when the tire 5 is mounted on a rim (not shown). The tire 5 has a decorative area 6 (dots are applied in FIG. 2) on a part of the outer surface 5s. The decorative area 6 is an area where a plurality of micro-protrusions are arranged. In the decorative area 6 of the present embodiment, for example, 2 There are two or more, specifically 2 to 10, micro-protrusions per 1 mm. Such micro-protrusions can reduce the reflection of light in the decorative area 6 and increase the blackness of the decorative area 6, which helps to improve the appearance performance of the tire 5. The decorative area 6 of the present embodiment is provided, for example, in the sidewall portion 7.

[0012] 1, the tire vulcanizing mold 1 of this embodiment includes a tread segment 1A, a sidewall segment 1B, and a bead ring 1C. In this embodiment, the decorative area 6 provided on the sidewall portion 7 of the tire 5 can be formed by the molding surface of the sidewall segment 1B.

[0013] 3 shows an enlarged perspective view of the molding surface 10 of the tire vulcanizing mold 1. The molding surface 10 of the tire vulcanizing mold 1 includes a first region 11 provided with a plurality of recesses 13 for forming a plurality of protrusions (microprotrusions) on the tire surface. A tire 5 vulcanized and molded in the tire vulcanizing mold 1 having such a molding surface 10 has a plurality of microprotrusions formed on the outer surface thereof that are the inverse shape of the recesses 13, thereby obtaining the decorative region 6 (shown in FIG. 2) described above.

[0014] In order to reliably reduce the reflection of light from the decorative region 6, it is desirable that the minute protrusions formed in the decorative region 6 are sufficiently small. 2 Two or more contact recesses 13 are arranged. Specifically, the first region 11 has a width of 1 mm. 2 It is desirable to arrange 2 to 10 contact recesses 13. 2 The number of hit recesses 13 can be calculated by dividing the number of recesses 13 that are completely contained within a 5 mm square plane by 25, for example.

[0015] The edge 14 defining the recess 13 is preferably, for example, circular, but is not limited to this, and various shapes such as an elliptical shape, a rectangular shape, or a polygonal shape may be adopted for the edge 14 of the recess 13.

[0016] FIG. 4 shows a cross-sectional view of the recess 13. As shown in FIG. 4, each of the recesses 13 includes a side wall surface 15, a bottom surface 20, and a virtual recess central axis line 13c extending in the depth direction of the recess 13. The recess central axis line 13c means a virtual line extending in the depth direction of the recess 13 through the centroid of the plane surrounded by the edge 14 of the recess 13. In the present embodiment, the plane surrounded by the edge 14 of the recess 13 is circular, and the recess central axis line 13c passes through the center of this circle.

[0017] In a cross-sectional view of the recess 13 including the recess central axis line 13c, the bottom surface 20 includes a bottom protrusion 25 that protrudes outward in the depth direction. Further, the side wall surface 15 includes an arc surface 16 that smoothly continues to the bottom surface 20. Due to the above-described configuration, the tire vulcanization mold 1 of the present disclosure is less likely to have dirt accumulate in the recess 13. Therefore, an increase in the frequency of mold cleaning can be suppressed. The reason is presumed to be the following mechanism.

[0018] The recesses of conventional tire vulcanization molds are configured such that their inner surfaces are relatively flat, and the bottom surface and the side wall surface are connected so as to form a ridge line. For this reason, during vulcanization molding, it is difficult for the rubber to peel off from the inner surface of the recess, and fine rubber pieces, dust, oil components from which the rubber precipitates, etc. are likely to accumulate in the recess.

[0019] On the other hand, in the present disclosure, as described above, the bottom protrusion 25 is formed on the bottom surface 20 of the recess 13, and the side wall surface 15 includes the arc surface 16. For this reason, when the mold is separated from the tire, the bottom protrusion 25 serves as a starting point for rubber peeling, and the rubber can be sequentially peeled off from the bottom protrusion 25 along the side wall surface 15. In particular, since the side wall surface 15 includes the arc surface 16, it is possible to effectively suppress the rubber from being torn during the sequential peeling of the rubber. It is presumed that such a mechanism can suppress the accumulation of dirt in the recess.

[0020] The following describes the more detailed configuration of the present embodiment. Each configuration described below shows a specific aspect of the present embodiment. Therefore, it goes without saying that the present disclosure can exhibit the above-described effects even if it does not have the configurations described below. Further, even if any one of the configurations described below is applied alone to the tire vulcanizing mold of the present disclosure having the above-described features, an improvement in performance corresponding to each configuration can be expected. Furthermore, when some of the configurations described below are applied in combination, a combined improvement in performance corresponding to each configuration can be expected.

[0021] The opening width W1 of the concave portion 13 is, for example, 0.5 mm or less, desirably 0.25 to 0.35 mm. Also, the maximum depth d1 of the concave portion 13 is, for example, 0.5 mm or less, and is 0.25 to 0.35 mm. However, the dimensions of the concave portion 13 are not limited to such a mode. Note that the dimensions of each part of the concave portion 13 are measured in a state where the tire vulcanizing mold 1 is cooled to room temperature unless otherwise specified.

[0022] In the present embodiment, since the bottom protrusion 25 is formed on the bottom surface 20, the deepest part of the concave portion 13 (hereinafter, may be referred to as the deepest part 26) is formed around the bottom protrusion 25. In a plan view of the concave portion 13 (not shown), the deepest part 26 has an annular shape, and the bottom surface 20 corresponds to a region surrounded by this annular deepest part 26. In the cross-sectional view of the concave portion 13 shown in FIG. 4, the deepest part 26 is substantially indicated by a point, and the bottom surface 20 is formed by the outer surface of the bottom protrusion 25. Further, an arc surface 16 communicates with the deepest part 26. In another aspect, the deepest part 26 may include a flat part. That is, a deepest part 26 formed of a flat part may be formed between the side wall surface 15 and the bottom protrusion 25. In this case, the outer surface of the bottom protrusion 25 and the flat part constituting the deepest part 26 are the bottom surface 20.

[0023] The side wall surface 15 extends, for example, inclined from the edge 14 of the concave portion 13. The angle θ1 of the side wall surface 15 with respect to the depth direction of the concave portion 13 is, for example, 5 to 35°, desirably 10 to 20°. Thereby, the reflection of light in the decorative region 6 to be formed is further suppressed.

[0024] From the viewpoint of ensuring the volume of the micro protrusions formed in the recess 13 and exerting the above-described effects, the radius of curvature r1 of the arc surface 16 of the side wall surface 15 is 0.070 mm or more, more preferably 0.085 mm or more, desirably 0.130 mm or less, and more preferably 0.115 mm or less.

[0025] In the cross-sectional view, the bottom protrusion 25 includes a top portion 25t that is located most outward in the depth direction of the recess 13, and a bottom protrusion side wall surface 27 that extends inward in the depth direction of the recess 13 from the top portion 25t. The top portion 25t of the present embodiment is arranged, for example, on the recess central axis 13c. The top portion 25t of the present embodiment has a pointed shape without a substantially flat surface. However, the top portion 25t may include a small flat surface.

[0026] The bottom protrusion side wall surface 27 is preferably an arc-shaped curve that is convex toward the recess central axis 13c. The radius of curvature r of the arc-shaped curve is 0.070 mm or more, more preferably 0.085 mm or more, desirably 0.130 mm or less, and more preferably 0.115 mm or less. In a more desirable aspect, the radius of curvature r2 is equal to the radius of curvature r1 of the arc surface 16 of the side wall surface 15. Thereby, in the cross-sectional view, it is desirable that the profiles of the arc surface 16 of the side wall surface 15 and the outer surface of the bottom protrusion 25 form a single arc. Such a bottom protrusion side wall surface 27 can effectively suppress the accumulation of dirt in the recess 13.

[0027] If the bottom protrusion 25 is small, there is a possibility that the above-described effects cannot be sufficiently obtained. On the other hand, if the bottom protrusion 25 is large, there is a possibility of causing a defect in the bottom protrusion 25 itself. From such a viewpoint, the height h1 of the bottom protrusion 25 is, for example, 10% or less of the depth d1 of the recess 13, desirably 1% to 5%. Specifically, the height h1 of the bottom protrusion 25 is desirably 0.050 mm or more, more preferably 0.010 mm or more, desirably 0.200 mm or less, and more preferably 0.015 mm or less.

[0028] From the same perspective, the width W2 of the bottom protrusion 25 is desirably 15% or more, more desirably 20% or more, and desirably 35% or less, more desirably 30% or less of the opening width W1 of the recess 13.

[0029] In a more desirable embodiment, each of the recesses 13 preferably has a target shape around the recess central axis 13c by having the above-described configuration. Thereby, it is possible to further suppress the accumulation of dirt in the recess 13.

[0030] FIGS. 5 and 6 show cross-sectional views of the recess 13 of another embodiment of the present disclosure. In the embodiments shown in FIGS. 5 and 6, the angle θ1 of the side wall surface 15 of the recess 13 is set larger than that in the embodiment shown in FIG. 4. In FIG. 5, an embodiment is shown in which the angle θ1 is 22.5° and the angle between the two side wall surfaces 15 in the cross-sectional view is 45°. Further, in FIG. 6, an embodiment is shown in which the angle θ1 is 30° and the angle between the two side wall surfaces 15 in the cross-sectional view is 60°. Even in such an embodiment, it is possible to effectively suppress the accumulation of dirt in the recess 13.

[0031] FIG. 7 shows a cross-sectional view when the recess 13 is formed in the molding surface 10. As shown in FIG. 7, the recess 13 of the present disclosure can be formed, for example, by a fine drill 30 attached to a radial ball grinder. Specifically, by revolving a fine drill 30 having a tip surface 30s corresponding to the side wall surface 15 of the recess 13 around the top 25t of the bottom protrusion 25 to form the recess 13, the recess 13 including the above-described bottom protrusion 25 can be obtained.

[0032] FIG. 8 shows a cross-sectional view when the recess 13 is formed in the molding surface 10 in a mode different from that in FIG. 7. In FIG. 8, the cross-sectional shape of the tip portion 31 of the fine drill 30 is shown. As shown in FIG. 8, in this mode, a recessed portion corresponding to the bottom protrusion 25 is provided on the outer surface 31s of the tip portion 31 of the fine drill 30. The recess 13 of the present disclosure can also be obtained by processing the molding surface 10 of the tire vulcanizing mold 1 with such a fine drill 30.

[0033] The tire vulcanization mold 1 of the present disclosure is applicable to known tire manufacturing methods. In a tire manufacturing method including a step of vulcanizing and molding a tire using the tire vulcanization mold 1 of the present disclosure, dirt is less likely to accumulate in the recesses 13 provided in the tire vulcanization mold 1, and therefore, an increase in the frequency of mold cleaning can be suppressed.

[0034] As shown in FIG. 2 , a tire vulcanized using the tire vulcanization mold 1 of the present disclosure has a plurality of microprotrusions formed in the decorative region 6, each having an inverted shape of the recess 13 described above. FIG. 9 shows an enlarged perspective view of one of the microprotrusions 33 arranged on the outer surface of the tire. As shown in FIG. 9 , this microprotrusion 33 includes a side surface 35, a protrusion apex 40, and an imaginary microprotrusion central axis 33c. The side surface 35 of the microprotrusion 33 has a shape corresponding to the side wall surface 15 of the recess 13. The protrusion apex 40 of the microprotrusion 33 has a shape corresponding to the bottom surface 20 of the recess 13.

[0035] In a cross-sectional view of the small protrusion including the small protrusion central axis 33c, the protrusion top 40 includes a top inner recess 45 that is recessed inward in the height direction of the small protrusion 33. In addition, the side surface 35 of the small protrusion 33 includes an arc surface 36 that smoothly continues to the protrusion top 40. Such small protrusions 33 can further suppress light reflection, helping to improve the appearance performance of the tire.

[0036] Although one embodiment of the present disclosure has been described in detail above, the present disclosure is not limited to the illustrated embodiment and can be modified and implemented in various aspects. [Example]

[0037] To confirm the effects of the present disclosure, tires were produced as examples using a tire curing mold having the recesses shown in Figures 4 to 6. As a comparative example, a tire was produced using a tire curing mold having the recess a shown in Figure 10. In the recess a of the comparative example, the side wall surface b and the bottom surface c are connected via a ridge line d. The dimensions of the recesses in the comparative example and each example are as follows: Comparative Example Cross section of recess: Figure 10 The opening width W1 of the recess = 0.30 mm The depth d1 of the recess = 0.30 mm The angle θ1 of the side wall surface of the recess = 15° Example 1 Cross-sectional view of the recess: Figure 4 The opening width W1 of the recess = 0.30 mm The depth d1 of the recess = 0.30 mm The angle θ1 of the side wall surface of the recess = 15° The height h1 of the bottom protrusion = 0.013 mm The radius of curvature r1 of the arc surface of the side wall surface = 0.010 mm The radius of curvature r2 of the arc-shaped curve of the side wall surface of the bottom protrusion = 0.010 mm Example 2 Cross-sectional view of the recess: Figure 5 The opening width W1 of the recess = 0.35 mm The angle θ1 of the side wall surface of the recess = 22.5° Example 3 Cross-sectional view of the recess: Figure 6 The opening width W1 of the recess = 0.40 mm The angle θ1 of the side wall surface of the recess = 30° In addition, the dimensions other than the above in Examples 2 and 3 are the same as those in Example 1.

[0038] Using the tire vulcanizing molds of the comparative example and Examples 1 to 3, a plurality of tires were produced without performing mold cleaning in the middle, and the blackness L* of the decorative area of each tire was measured using a color difference meter. The blackness L* is measured in accordance with the lightness of JIS Z8721. The blackness L* is a black with a lower lightness as the numerical value is smaller, which is desirable as the decorative area of the tire.

[0039] Figure 11 shows the relationship between the number of tires produced N and the blackness L* in the comparative example and Examples 1 to 3. The graphs g1 to g3 in Figure 11 correspond to Examples 1 to 3, and the graph g4 corresponds to the comparative example.

[0040] As shown in FIG. 11, in the Comparative Example and Examples 1 to 3, the blackness L* deteriorates (the numerical value increases) as the number of tires produced increases. This is due to the accumulation of dirt in the recesses of the vulcanization mold. On the other hand, it can be seen that the rate of deterioration in blackness L* is significantly smaller in Examples 1 to 3 than in the Comparative Example. For example, when the allowable value for blackness L* is set to 14, the Comparative Example could only produce about 800 tires, while Examples 1 to 3 could produce more than three times as many tires as the Comparative Example. In other words, it was confirmed that the tire vulcanization mold of the present disclosure significantly suppresses the accumulation of dirt in the recesses.

[0041] [Note] The present disclosure includes the following aspects.

[0042] [Disclosure 1] A tire vulcanization mold, a molding surface for molding the tire during vulcanization molding; the molding surface includes a first region provided with a plurality of recesses for forming a plurality of protrusions on the tire surface, The first region has a thickness of 1 mm 2 Two or more of the contact recesses are arranged, Each of the recesses includes a side wall surface, a bottom surface, and a virtual recess center axis extending in a depth direction of the recess, In a cross-sectional view of the recess including the recess central axis, the bottom surface includes a bottom protrusion that is convex outward in the depth direction, The side wall surface includes an arcuate surface that smoothly connects to the bottom surface. Tire vulcanization mold. [Disclosure 2] In the cross-sectional view, the bottom protrusion includes an apex portion located outermost in a depth direction of the recess, and a bottom protrusion sidewall surface extending inward in the depth direction of the recess from the apex portion, The tire vulcanization mold according to Disclosure 1, wherein the bottom protrusion side wall surface is an arc-shaped curve convex toward the central axis of the recess. [Disclosure 3] A tire vulcanization mold according to Disclosure 2, wherein the radius of curvature of the arc-shaped curve is equal to the radius of curvature of the arc surface. [Disclosure 4] The tire vulcanizing mold according to any one of Disclosures 1 to 3, wherein each of the recesses has a symmetrical shape about a central axis of the recess. [Disclosure 5] the bottom surface is a region surrounded by the deepest part of the recess in the depth direction, The tire vulcanizing mold according to any one of Disclosures 1 to 4, wherein the arcuate surface is in communication with the deepest portion. [Disclosure 6] The tire vulcanizing mold according to any one of Disclosures 1 to 5, wherein the bottom surface is made of the bottom protrusion. [Disclosure 7] 7. The tire vulcanizing mold according to any one of Disclosures 1 to 6, wherein the height of the bottom protrusion is 0.050 to 0.200 mm. [Disclosure 8] 8. The tire vulcanizing mold according to any one of Disclosures 1 to 7, wherein the radius of curvature of the arcuate surface is 0.085 to 0.115 mm. [Disclosure 9] A method for manufacturing a tire, comprising a step of vulcanizing and molding a tire using the tire vulcanization mold according to any one of Disclosures 1 to 8. [Disclosure 10] A tire vulcanized and molded using the tire vulcanization mold according to any one of Disclosures 1 to 8. [Disclosure 11] A tire, the tire outer surface includes a decorative area having a plurality of microprotrusions arranged thereon; each of the microprotrusions includes a side surface, a protrusion apex, and an imaginary microprotrusion central axis; In a cross-sectional view of the microprotrusion including the central axis of the microprotrusion, the projection top includes a top inner recess recessed inward in the height direction of the small projection, the side surface includes an arcuate surface smoothly continuing to the top of the projection; tire. [Explanation of symbols]

[0043] 1 Tire vulcanizing mold 10 Forming surface 11 First region 13 Recess 13c Recess central axis 15 Side wall surface 16 Arc surface 20 Bottom surface

Claims

1. A tire vulcanizing mold, comprising: a molding surface for molding a tire during vulcanization molding; the molding surface includes a first region provided with a plurality of recesses for forming a plurality of protrusions on the tire surface; In the first region, there are two or more of the concave portions per 1 mm 2 arranged therein, each of the recesses includes a side wall surface, a bottom surface, and a virtual recess central axis extending in the depth direction of the recess; in a cross-sectional view of the recess including the recess central axis; the bottom surface includes a bottom protrusion that protrudes outward in the depth direction; the side wall surface includes an arc surface that smoothly continues to the bottom surface; the height of the bottom protrusion is 10% or less of the depth of the recess; A tire vulcanizing mold.

2. in the cross-sectional view, the bottom protrusion includes a top portion located most outward in the depth direction of the recess and a bottom protrusion side wall surface extending inward in the depth direction of the recess from the top portion; the bottom protrusion side wall surface is an arc-shaped curve that protrudes toward the recess central axis. The tire vulcanizing mold according to claim 1.

3. A tire vulcanizing mold, comprising: a molding surface for molding a tire during vulcanization molding; the molding surface includes a first region provided with a plurality of recesses for forming a plurality of protrusions on the tire surface; in the first region, two or more of the recesses are arranged per 1 mm 2; each of the recesses includes a side wall surface, a bottom surface, and a virtual recess central axis extending in the depth direction of the recess; in a cross-sectional view of the recess including the recess central axis; the bottom surface includes a bottom protrusion that protrudes outward in the depth direction; the side wall surface includes an arc surface that smoothly continues to the bottom surface; in the cross-sectional view, the bottom protrusion includes a top portion located most outward in the depth direction of the recess and a bottom protrusion side wall surface extending inward in the depth direction of the recess from the top portion; the bottom protrusion side wall surface is an arc-shaped curve that protrudes toward the recess central axis; the top portion is a pointed shape without a flat surface; A tire vulcanizing mold.

4. The radius of curvature of the arc-shaped curve is equal to the radius of curvature of the arc surface. The tire vulcanizing mold according to claim 2 or 3.

5. Each of the recesses has a symmetrical shape around the recess central axis. The tire vulcanizing mold according to any one of claims 1 to 4.

6. The bottom surface is a region surrounded by the deepest portion in the depth direction of the recess; the arc surface communicates with the deepest portion. The tire vulcanizing mold according to any one of claims 1 to 5.

7. The tire vulcanization mold according to any one of claims 1 to 6, wherein the bottom surface is composed of the bottom protrusions.

8. The tire vulcanization mold according to any one of claims 1 to 7, wherein the height of the bottom protrusions is 0.050 to 0.200 mm.

9. The tire vulcanization mold according to any one of claims 1 to 8, wherein the radius of curvature of the arc surface is 0.085 to 0.115 mm.

10. A method for manufacturing a tire, comprising a step of vulcanizing and molding the tire using the tire vulcanization mold according to any one of claims 1 to 9.

11. A tire vulcanized and molded with the tire vulcanization mold according to any one of claims 1 to 9.

12. A tire, comprising: wherein an outer surface of the tire includes a decorative region in which a plurality of micro-protrusions are arranged; each of the micro-protrusions includes a side surface, a protrusion top, and a virtual micro-protrusion central axis; in a cross-sectional view of the micro-protrusion including the micro-protrusion central axis; the protrusion top includes a top inner recess that is recessed inward in the height direction of the micro-protrusion; the side surface includes an arc surface that smoothly continues to the protrusion top; the depth of the top inner recess is 10% or less of the height of the micro-protrusion. A tire.

13. A tire, comprising: wherein an outer surface of the tire includes a decorative region in which a plurality of micro-protrusions are arranged; each of the micro-protrusions includes a side surface, a protrusion top, and a virtual micro-protrusion central axis; in a cross-sectional view of the micro-protrusion including the micro-protrusion central axis; the protrusion top includes a top inner recess that is recessed inward in the height direction of the micro-protrusion; the side surface includes an arc surface that smoothly continues to the protrusion top; in the cross-sectional view, the top inner recess includes a portion that is located most inward in the height direction of the micro-protrusion; the portion located most inward is a pointed shape without a flat surface. A tire.

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