JP2024082065A - Pneumatic tires - Google Patents

Abstract

The present invention aims to improve the appearance performance of a sidewall portion by making appearance defects such as bulge dents less noticeable, while increasing the strength of the molding surface of a mold.
[Solution] A pneumatic tire has a decorative area 9 formed on the outer surface of a sidewall portion 3. The decorative area 9 includes a reference surface 10 and a plurality of microprotrusions 11 protruding from the reference surface 10. In a plan view of the reference surface 10, the plurality of microprotrusions 11 include a pattern portion 15 in which a plurality of first microprotrusion rows 12 and a plurality of second microprotrusion rows 13 are alternately arranged in a first direction f1. When the pattern portion 15 is virtually divided into a plurality of triangular regions t with three directly adjacent microprotrusions 11 as vertices v, the plurality of triangular regions t include at least one first triangular region t1 provided with a raised portion 20 that protrudes from the reference surface 10 at a height smaller than that of the microprotrusions 11.
[Selected figure] Figure 3

Description

The present invention relates to a pneumatic tire.

The following Patent Document 1 describes a tire with a decorative band on the surface of the sidewall portion. The decorative band has a serration region in which ridges, including continuous ridges and interrupted ridges with interruptions, are arranged in parallel in the tire circumferential direction. Such a decorative body has the effect of making bulge dents, which tend to detract from the appearance of the tire, less noticeable.

JP 2019-094008 A

In recent years, in order to make appearance defects such as bulge dents less noticeable and to further improve the appearance performance of the sidewall portion, multiple small protrusions are sometimes formed densely on the sidewall portion. Such microprotrusions are usually formed by multiple small recesses machined into the molding surface of the sidewall mold that vulcanizes and molds the sidewall portion. However, molds machined with multiple small recesses have problems such as low strength of the molding surface and poor rubber flow during vulcanization.

The present invention was devised in consideration of the above-mentioned circumstances, and its main objective is to provide a pneumatic tire that can improve the appearance performance of the sidewall portion while increasing the strength of the molding surface of the mold.

The present invention is a pneumatic tire vulcanized in a mold, comprising a tread portion and a pair of sidewall portions extending radially inward from the tread portion, a decorative area formed on the outer surface of at least one of the pair of sidewall portions, the decorative area comprising a reference surface and a plurality of micro-projections protruding from the reference surface, the plurality of micro-projections comprising a pattern portion in which a plurality of first micro-projection rows and a plurality of second micro-projection rows are alternately arranged in a first direction in a plan view of the reference surface, the plurality of micro-projections in the first micro-projection row are arranged at a first pitch in a second direction perpendicular to the first direction, the plurality of micro-projections in the second micro-projection row are arranged at the first pitch in the second direction and are offset in position from the first micro-projection row in the second direction, and when the pattern portion is virtually divided into a plurality of triangular regions with three of the micro-projections directly adjacent to each other as vertices, the plurality of triangular regions include at least one first triangular region provided with a protuberance protruding from the reference surface at a height smaller than the height of the micro-projections.

By adopting the above-mentioned configuration, the pneumatic tire of the present invention can make appearance defects such as bulge dents less noticeable, improving the appearance performance of the sidewall portion while increasing the strength of the molding surface of the mold.

1 is a tire meridian cross-sectional view showing one embodiment of a pneumatic tire of the present invention. FIG. 2 is a partial cross-sectional view of the sidewall portion of FIG. 1 . FIG. FIG. 1A is a cross-sectional view of a mold having a forming surface for forming raised portions, and FIG. 1B is a cross-sectional view of a mold having a forming surface for forming only minute protrusions. FIG. FIG. 7 is a cross-sectional view taken along line AA in FIG. 6. 13A and 13B are plan views of a reference surface for explaining a first triangular region and a second triangular region. 1A is a perspective view of a microprotrusion of this embodiment, FIG. 1B is a perspective view of a microprotrusion of another embodiment, and FIG. 1C is a perspective view of a microprotrusion of yet another embodiment. 10A is a front view of a decorative area according to another embodiment, and FIG. 10B is a cross-sectional view taken along line BB of FIG. 13A is a front view of a decorative region of still another embodiment, and FIG. 13B is a front view of a decorative region of still another embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In order to facilitate understanding of the present invention, the drawings include exaggerated representations and representations different from the dimensional ratios of the actual structures. In addition, when there are multiple embodiments, the same or common elements are designated by the same reference numerals throughout the specification, and duplicated explanations are omitted.

Figure 1 is a tire meridian cross-sectional view of one embodiment of a pneumatic tire (hereinafter sometimes simply referred to as "tire") 1 of the present invention. In Figure 1, a tire 1 for passenger cars is shown as a preferred embodiment. However, the present invention may also be adopted, for example, in tires 1 for motorcycles and heavy loads. The tire 1 is formed by vulcanizing a green tire 1a in a mold T (part of which is shown in Figure 4) of known structure.

In this specification, unless otherwise specified, the dimensions of each part of the tire 1 are measured in a normal state. "Normal state" means that the tire 1 is mounted on a normal rim (not shown), inflated to the normal internal pressure, and unloaded.

A "genuine rim" is a rim that is specified for each tire by the standard system that includes the standard on which the tire is based. For example, in the case of JATMA, it is called a "standard rim," in the case of TRA, it is called a "design rim," and in the case of ETRTO, it is called a "measuring rim."

"Normal internal pressure" is the air pressure set for each tire by each standard in the standard system on which the tire is based. For JATMA, it is the "maximum air pressure." For TRA, it is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES." For ETRTO, it is the "INFLATION PRESSURE."

The tire 1 of this embodiment includes a tread portion 2 and a pair of sidewall portions 3 extending radially inward from the tread portion 2. The tire 1 also includes a bead portion 4 that is disposed radially inward of each sidewall portion 3 and has a bead core 5 embedded therein.

A decorative area 9 is formed on the outer surface 3A of at least one of the pair of sidewall portions 3. For example, the decorative area 9 is formed on both of the pair of sidewall portions 3. The sidewall portion 3 including the decorative area 9 is formed in black by blending carbon black.

Figure 2 is a cross-sectional view of the sidewall portion 3 for conceptually explaining the decorative area 9. As shown in Figures 1 and 2, the decorative area 9 includes a reference surface 10 and a number of micro-projections 11 protruding from the reference surface 10. Incident light that hits the micro-projections 11 is reflected by other micro-projections 11 at different reflection angles, and is absorbed by repeating this reflection. Therefore, the decorative area 9 has a relatively low light reflectance compared to other areas. Since the sidewall portion 3 is formed in black, the decorative area 9 has a relatively high degree of blackness compared to other parts.

Figure 3 is a plan view of the reference surface 10 (sidewall portion 3). As shown in Figure 3, in the plan view of the reference surface 10, the multiple micro-projections 11 include a pattern portion 15 in which multiple first micro-projection rows 12 and multiple second micro-projection rows 13 are alternately arranged in the first direction f1.

The first micro-projection row 12 has a plurality of micro-projections 11 arranged at a first pitch P1 in a second direction f2 perpendicular to the first direction f1. The second micro-projection row 13 has a plurality of micro-projections 11 arranged at a first pitch P1 in the second direction f2, and is misaligned from the first micro-projection row 12 in the second direction f2. In this embodiment, the micro-projections 11 of the first micro-projection row 12 are misaligned from the micro-projections 11 of the second micro-projection row 13 in the second direction f2 by 50% of the first pitch P1.

In the present invention, the pattern portion 15 is virtually divided into a plurality of triangular regions t with three micro-projections 11 directly adjacent to each other as vertices v. In this virtual division, the plurality of triangular regions t includes at least one first triangular region t1 provided with a protuberance 20 protruding from the reference surface 10 at a height smaller than that of the micro-projections 11. The first triangular region t1 appears relatively brighter than the triangular region t in which the protuberance 20 is not formed, because it reduces the chance that the irradiated light is reflected and absorbed by other micro-projections 11. As a result, a difference (gradation) in the blackness occurs in the entire decorative region 9. Therefore, the user's eyes are drawn to the gradation of the decorative region 9, and the bulge dent becomes less noticeable. Therefore, the appearance performance of the sidewall portion 3 is further improved. In FIG. 3, the protuberance 20 is shown colored for convenience.

4(A) and 4(B) are cross-sectional views of a mold T for vulcanizing a raw tire 1a. FIG. 4(A) shows the molding surface Ta of the mold T for molding the micro-projections 11 and the raised portion 20. In the molding surface Ta, a first triangular region t1 (shown in FIG. 3) is formed. As shown in FIG. 4(A), the molding surface Ta includes a fine recess R1 for molding the micro-projections 11, and a shallow recess R2 for molding the raised portion 20 between the two fine recesses R1, R1. In this way, the molding surface Ta provided with the shallow recess R2 not only improves the strength of the mold T, but also makes it easier for the rubber being vulcanized to move between the fine recesses R1, R1. Therefore, the mold T for vulcanizing the tire 1 of the present invention has high strength and generates a smooth rubber flow. In addition, FIG. 4(B) shows the molding surface Tb of the mold T for molding only the micro-projections 11. As shown in FIG. 4(B), only the fine recesses R1 are formed on the molding surface Tb.

As shown in FIG. 1, a carcass 6 is disposed inside the tire 1. The carcass 6 includes, for example, a main body portion 6a extending between the bead cores 5 on both sides, and a pair of folded-back portions 6b that are connected to the main body portion 6a and folded back from the inside to the outside in the tire axial direction at the bead core 5. The outer end 6e of the folded-back portion 6b in the tire radial direction is located in the sidewall portion 3. In this embodiment, the outer end 6e of the folded-back portion 6b overlaps with the decorative area 9 in the tire radial direction. The outer end 6e of the folded-back portion 6b is a location where a bulge dent is likely to occur during the manufacture of the tire 1. Therefore, the tire 1 of this embodiment can make the bulge dent formed by the outer end 6e less noticeable.

In this embodiment, the reference surface 10 coincides with the outer surface 3a of the sidewall portion 3, which can determine the cross-sectional width of the tire 1 (see JATMA) in the tire meridian cross section. Note that the reference surface 10 is not limited to this form, and may be a surface that protrudes in a step shape from the outer surface 3a outward in the tire axial direction.

Figure 5 is a partial front view of the sidewall portion 3. As shown in Figure 5, in this embodiment, the decorative area 9 is formed so as to be continuous in the tire circumferential direction. For example, the decorative area 9 may be formed so as to be interrupted in the tire circumferential direction. For example, the decorative area 9 is desirably disposed at a position that is 40% to 90% of the tire cross-sectional height HB outward in the tire radial direction from the bead baseline BL (shown in Figure 1). In this specification, the "bead baseline BL" is a tire axial line that passes through the rim diameter position determined by the standard to which the tire 1 is based. In Figure 5, the decorative area 9 is shown in color.

Although not particularly limited, the area A1 of the decorative region 9 is desirably, for example, 100 mm2 or more, and more desirably, 200 mm2 or more. Since the area A1 of the decorative region 9 is 200 ^mm2 or more, the portion with a relatively high blackness becomes large, and the appearance performance of the sidewall portion 3 can be reliably improved. In such a decorative region 9, the number of microprotrusions 11 is desirably 7 or more, and more desirably 50 or more. Since there are 7 or more microprotrusions 11 per decorative region 9, the effect of reducing the amount of light due to the reflection of light between the microprotrusions 11 is maintained, and the blackness is increased.

As shown in FIG. 3, in this specification, the first direction f1 is the tire radial direction, and the second direction f2 is the tire circumferential direction. When the first direction f1 is the tire radial direction, the lower side of the figure is the inner side in the tire radial direction, and the upper side of the figure is the outer side in the tire radial direction. For convenience, in FIG. 3, the first direction f1 is shown parallel to the up-down direction of the figure, and the second direction f2 is shown parallel to the lateral direction of the figure. Note that the first direction f1 may be the tire circumferential direction, and the second direction f2 may be the tire radial direction. Also, the first direction f1 may be a direction inclined with respect to the tire radial direction.

In this embodiment, each of the triangular regions t has three imaginary edges 17 that connect the three micro-projections 11 to each other. Each of the three imaginary edges 17 is adjacent to, for example, one of the multiple triangular regions t. In this embodiment, each of the three imaginary edges 17 is adjacent to (common to) one of the imaginary edges 17 of the multiple triangular regions t. In a front view of the reference surface 10, each of the triangular regions t in this embodiment is formed in an equilateral triangle. This improves the appearance of the decorative region 9 and improves the appearance performance. Note that the shape of the triangular regions t is not limited to this form, and may be, for example, an isosceles triangle or a right-angled isosceles triangle.

The first triangular region t1 is adjacent to another first triangular region t1 on at least one of the three imaginary edges 17, for example. This increases the area of the decorative region 9 that appears relatively bright due to the first triangular region t1, and thus the area of the gradation, thereby further improving the appearance performance.

In this embodiment, the multiple triangular regions t include a second triangular region t2 that does not have a raised portion 20. The second triangular region t2 has a higher blackness than the first triangular region t1. Thus, in the decorative region 9 of this embodiment, the first triangular region t1 and the second triangular region t2 are formed, so that the gradation of the decorative region 9 is clearly formed, improving the appearance performance.

6 is a partial plan view (plan view of the reference surface 10) of the decorative area 9 of this embodiment. FIG. 7 is a cross-sectional view taken along line A-A of FIG. 6. As shown in FIGS. 6 and 7, the multiple triangular areas t of the decorative area 9 include at least one group 21 of multiple first triangular areas t1 arranged adjacent to each other. For example, the group 21 extends such that the multiple first triangular areas t1 are arranged at an incline with respect to the first direction f1. In this embodiment, the group 21 extends such that the multiple first triangular areas t1 are arranged at an incline with respect to the tire radial direction. For example, the group 21 is arranged such that the multiple first triangular areas t1 are arranged so that they are continuously inclined in the same direction with respect to the tire radial direction. In this embodiment, the group 21 extends continuously between the outer end 9e (shown in FIG. 1) and the inner end 9i in the tire radial direction of the decorative area 9. This aspect increases the gradation, thereby enhancing the effect of making the bulge dent less noticeable. In FIG. 6, the raised portion 20 is shown in color.

In this embodiment, the multiple triangular regions t are arranged in groups 21 in a regular pattern. This further enhances the effect of making the bulge dent less noticeable. In this embodiment, the groups 21 are arranged at intervals in the tire circumferential direction.

In a plan view of the reference surface 10, the first triangular region t1a located at the end 21e of the group 21 is adjacent to another first triangular region t1 at one of the three imaginary edges 17. In this embodiment, each of the first triangular regions t1a located at both ends 21e, 21e of the group 21 is adjacent to another first triangular region t1 at one of the three imaginary edges 17. In this embodiment, both ends 21e, 21e of the group 21 form the outer end 9e and inner end 9i of the decorative region 9.

In a plan view of the reference surface 10, the first triangular region t1b located except for the end 21e of the group 21 has two of the three imaginary sides 17 adjacent to other first triangular regions t1. In this embodiment, the group 21 is formed by arranging a plurality of group parts 21A, each of which has four first triangular regions t1 arranged in the tire circumferential direction, in the tire radial direction. Each group part 21A is, for example, misaligned in the second direction f2. The first triangular region t1x at the end of the first tire circumferential direction of one group part 21a and the first triangular region t1y at the end of the second tire circumferential direction of the group part 21b adjacent to this group part 21a in the tire radial direction are connected via the imaginary side part 17. The first tire circumferential direction is the left side in the figure, and the second tire circumferential direction is the right side in the figure. In this embodiment, the first triangular region t1y is located inside the first triangular region t1x in the tire radial direction. Such a group 21 can be made longer to improve its effectiveness in making bulging dents less noticeable.

The decorative region 9 of this embodiment includes sub-groups 22 formed by arranging a plurality of second triangular regions t2 adjacent to each other on both sides of the group 21 of the first triangular region t1 in the tire circumferential direction. In this embodiment, the sub-groups 22 are formed in the same shape as the group 21. In other words, the sub-groups 22 of this embodiment are formed by arranging sub-group parts 22A, in which four second triangular regions t2 are arranged in the tire circumferential direction, in the tire radial direction. The second triangular region t2x at the first tire circumferential end of one sub-group part 22a and the second triangular region t2y at the second tire circumferential end of the sub-group part 22b adjacent to the sub-group part 22a in the tire radial direction are connected via the imaginary side part 17.

In the first triangular region t1, the raised portion 20 is connected to, for example, at least one of the three adjacent micro-protrusions 11. This can further increase the strength of the mold T and effectively improve the flow of rubber during vulcanization. In addition, such a raised portion 20 increases the rigidity of the micro-protrusions 11, suppressing tearing and chipping, and exhibits an effect of improving the appearance performance of the sidewall portion 3 for a long period of time. In the first triangular region t1, in this embodiment, the raised portion 20 is connected to all three adjacent micro-protrusions 11 (as shown in FIG. 3).

It is preferable that 20% to 80% of the plurality of triangular regions t are the first triangular regions t1. In other words, it is preferable that the total area Aw (not shown) of all the raised portions 20 is 20% or more and 80% or less of the area Ax (not shown) of the decorative region 9 in a plan view of the reference surface 10. Since the total area Aw of the raised portions 20 is 20% or more and 80% or less of the area Ax of the decorative region 9, the user can clearly recognize the black gradation. In order to effectively exert such an effect, it is more preferable that the total area Aw of the raised portions 20 is 30% or more and 70% or less of the area Ax of the decorative region 9. In this specification, the area Ax of the decorative region 9 is the total area of all the triangular regions t (including the micro-protrusions 11) in a plan view of the reference surface 10.

8(A) and 8(B) are plan views of the reference surface 10 for explaining the first triangular region t1 and the second triangular region t2. As shown in FIG. 8(A), in this specification, the first triangular region t1 refers to a region in which the protuberance 20 is located at the centroid Ce of the triangular region t, and the area Ap of the protuberance 20 located within the triangular region t is 60% or more of the area As of the triangular region t excluding the minute protrusions 11. The left triangular region t shown in FIG. 8(B) is the first triangular region t1 because the protuberance 20 is located at the centroid Ce of the triangular region t, and the area Ap is 60% or more of the area As. The right triangular region t shown in FIG. 8(B) is the second triangular region t2 because the protuberance 20 formed within the region is not located at the centroid Ce of the triangular region t. The area As is shown in FIG. 6.

9(A) is a perspective view of the micro-projection 11. As shown in FIG. 9(A), the micro-projection 11 is in the shape of a truncated cone in this embodiment. The micro-projection 11 includes, for example, a side surface 11a inclined with respect to the protruding height direction and a circular top 11b located at the outermost side in the protruding height direction. The side surface 11a reflects the irradiated light in multiple directions and to a larger number of the micro-projections 11, thereby further increasing the blackness of the decorative area 9. In this embodiment, the top 11b is formed as a flat surface. Such a top 11b increases the rigidity of the micro-projection 11 and suppresses the bending or chipping of the micro-projection 11, thereby maintaining high appearance performance. In addition, the micro-projection 11 includes a bottom surface 11c formed at the boundary between the side surface 11a and the reference surface 10. In this embodiment, the bottom surface 11c is parallel to the top 11b. In this specification, the "protrusion height" refers to the height in the direction of the normal n (shown in FIG. 7) of the bottom surface 11c of the microprotrusion 11.

As shown in FIG. 7, the protruding height h1 of the micro-protrusion 11 from the reference plane 10 is preferably 0.1 mm or more, more preferably 0.2 mm or more, more preferably 1.0 mm or less, and more preferably 0.8 mm or less. The diameter d of the top 11b of the micro-protrusion 11 is preferably 0.05 mm or more, more preferably 0.15 mm or more, more preferably 0.5 mm or less, and more preferably 0.35 mm or less. The angle θ between the generating line m (formed by the side surface 11a) of the micro-protrusion 11 and the bottom surface 11c is preferably 5 degrees or more, more preferably 10 degrees or more, more preferably 75 degrees or less, and more preferably 65 degrees or less.

The raised portion 20 includes, for example, a raised apex surface 20a that protrudes furthest outward in the tire axial direction. The raised apex surface 20a is formed, for example, parallel to the reference surface 10. Note that the raised portion 20 is not limited to this form, and for example, the raised apex surface 20a may be formed in a tapered shape toward the outside in the projection height direction (not shown).

Although not particularly limited, the protruding height h2 of the raised portion 20 is preferably 0.05 mm or more, more preferably 0.1 mm or more, more preferably less than 1.0 mm, and even more preferably 0.8 mm or less.

In this embodiment, the protruding height h1 of all the micro-projections 11 arranged in the decorative area 9 is the same. In addition, the protruding height h2 of all the raised portions 20 arranged in the decorative area 9 is the same. In this specification, the term "equivalent" includes not only cases where the protruding heights are the same, but also cases where the protruding heights differ due to precision errors during tire manufacturing. In addition, the term "equivalent" also includes cases where the difference (ha-hb) between the maximum protruding height ha (not shown) and the minimum protruding height hb is 10% or less of the minimum value hb.

Figure 10 (A) is a front view (plan view of the reference surface 10) of a decorative area 9 of another embodiment. Figure 10 (B) is a cross-sectional view of line B-B of Figure 10 (A). As shown in Figure 10, in the decorative area 9 of this embodiment, the raised portion 20 includes a first raised portion 20A, a second raised portion 20B, and a third raised portion 20C. In this embodiment, the first raised portion 20A has a smaller protruding height than the second raised portion 20B, and the second raised portion 20B has a smaller protruding height than the third raised portion 20C. The first raised portion 20A, the second raised portion 20B, and the third raised portion 20C each form one first triangular region t1. The first triangular region t1 in which the first raised portion 20A is provided has a lower light reflectance and a higher blackness than the first triangular region t1 in which the second raised portion 20B is provided. The first triangular region t1 where the second raised portion 20B is provided has a lower light reflectance and a higher blackness than the first triangular region t1 where the third raised portion 20C is provided. Thus, in this embodiment, the decorative region 9 is divided into four levels of light and dark blackness, which has the effect of making high bulge dents less noticeable.

Figure 11 (A) is a front view (plan view of the reference surface 10) of a decorative area 9 of yet another embodiment. As shown in Figure 11 (A), the decorative area 9 of this embodiment is formed such that the groups 21 extend at an angle with respect to the first direction f1. In this embodiment, each group 21 is formed in a parallelogram shape. Also, the sub-groups 22 are formed in the same shape as the groups 21.

Figure 11 (B) is a front view (plan view of the reference surface 10) of a decorative area 9 of yet another embodiment. As shown in Figure 11 (B), the decorative area 9 of this embodiment is formed so that the groups 21 extend parallel to the second direction f2. In this embodiment, each group 21 is formed in an annular shape in a side view of the tire 1. In addition, the sub-groups 22 are formed in the same shape as the groups 21.

Figure 9 (B) is a perspective view of the microprotrusion 11 of another embodiment. As shown in Figure 9 (B), the microprotrusion 11 of this embodiment is formed in a hexagonal truncated pyramid shape. Such a microprotrusion 11 can also achieve the effects of the present invention. The microprotrusion 11 may also be formed in a polygonal truncated pyramid shape, including a triangular truncated pyramid.

Figure 9 (C) is a perspective view of the micro-projection 11 of yet another embodiment. As shown in Figure 9 (C), the micro-projection 11 of this embodiment includes a recess 24 that extends downward in the protruding height direction from the top 11b. As a result, the light irradiated into the recess 24 is repeatedly reflected within the recess 24, further reducing the amount of light, which helps to increase the blackness of the decorative area 9.

The above describes in detail a particularly preferred embodiment of the present invention, but the present invention is not limited to the illustrated embodiment and can be modified and implemented in various ways.

[Additional Notes]
The present invention includes the following aspects.

[Invention 1]
A pneumatic tire vulcanized in a mold,
The tire includes a tread portion and a pair of sidewall portions extending radially inward from the tread portion,
A decorative area is formed on an outer surface of at least one of the pair of sidewall portions,
The decorative region includes a reference surface and a plurality of small protrusions protruding from the reference surface;
In a plan view of the reference surface, the plurality of micro-projections include a pattern portion in which a plurality of first micro-projection rows and a plurality of second micro-projection rows are alternately arranged in a first direction,
The first small protrusion row has a plurality of small protrusions arranged at a first pitch in a second direction perpendicular to the first direction,
the second micro-projection row has a plurality of micro-projections arranged at the first pitch in the second direction and is offset in position from the first micro-projection row in the second direction;
When the pattern portion is virtually divided into a plurality of triangular regions having three directly adjacent microprotrusions as vertices, the plurality of triangular regions include at least one first triangular region provided with a protrusion protruding from the reference surface at a height smaller than that of the microprotrusions.
Pneumatic tires.
[Invention 2]
The pneumatic tire according to claim 1, wherein in the first triangular region, the raised portion is connected to at least one of the three adjacent small protrusions.
[The present invention 3]
The pneumatic tire according to claim 1 or 2, wherein in the first triangular region, the raised portion is connected to all of the three adjacent small protrusions.
[Invention 4]
The pneumatic tire according to any one of claims 1 to 3, wherein the plurality of triangular regions includes a second triangular region that does not include the raised portion.
[Invention 5]
The pneumatic tire according to any one of claims 1 to 4, wherein the plurality of triangular regions includes at least one group of the plurality of first triangular regions arranged adjacent to each other.
[Invention 6]
The pneumatic tire according to claim 5, wherein the plurality of triangular regions are arranged in a regular pattern in the groups.
[Invention 7]
Each of the plurality of triangular regions has three imaginary sides respectively connecting the three small protrusions to each other,
each of the three imaginary sides is adjacent to any of the plurality of triangular regions;
The pneumatic tire according to claim 6, wherein the first triangular region is adjacent to another first triangular region at at least one of the three imaginary sides.
[The present invention 8]
A pneumatic tire as described in claim 7, wherein, in a planar view of the reference plane, the first triangular region located at the end of the group is adjacent to one of the three imaginary edges, and another of the first triangular regions is adjacent to the other first triangular region.
[The present invention 9]
A pneumatic tire as described in claim 7 or 8, wherein, in a planar view of the reference plane, the first triangular region located excluding the ends of the group has other first triangular regions adjacent to two of the three imaginary edges.
[Invention 10]
The pneumatic tire according to any one of claims 1 to 9, wherein 20% to 80% of the plurality of triangular regions are the first triangular regions.
[Invention 11]
The pneumatic tire according to any one of claims 1 to 10, wherein the small protrusions are frustum-shaped.
[Invention 12]
The diameter of the tip of the microprojection is 0.05 to 0.5 mm;
The protruding height of the minute protrusion from the reference surface is 0.1 to 1.0 mm;
12. The pneumatic tire according to claim 11, wherein an angle between a generatrix of the small projection and a bottom surface is 5 to 75 degrees.
[The present invention 13]
13. The pneumatic tire according to any one of claims 1 to 12, wherein the protruding height of the raised portion is 0.05 mm or more and less than 1.0 mm.

Reference Signs List 1 Pneumatic tire 3 Sidewall portion 3A Outer surface 9 Decorative region 10 Reference surface 11 Micro-projections 12 First micro-projection row 13 Second micro-projection row f1 First direction 15 Pattern portion 20 Raised portion t Triangular region t1 First triangular region v Vertex

Claims (13)

A pneumatic tire vulcanized in a mold,
The tire includes a tread portion and a pair of sidewall portions extending radially inward from the tread portion,
A decorative area is formed on an outer surface of at least one of the pair of sidewall portions,
The decorative region includes a reference surface and a plurality of small protrusions protruding from the reference surface;
In a plan view of the reference surface, the plurality of micro-projections include a pattern portion in which a plurality of first micro-projection rows and a plurality of second micro-projection rows are alternately arranged in a first direction,
The first micro-projection row has a plurality of the micro-projections arranged at a first pitch in a second direction perpendicular to the first direction,
the second micro-projection row has a plurality of micro-projections arranged at the first pitch in the second direction and is offset in position from the first micro-projection row in the second direction;
When the pattern portion is virtually divided into a plurality of triangular regions having three directly adjacent microprotrusions as vertices, the plurality of triangular regions include at least one first triangular region provided with a protrusion protruding from the reference surface at a height smaller than that of the microprotrusions.
Pneumatic tires. The pneumatic tire according to claim 1, wherein in the first triangular region, the raised portion is connected to at least one of the three adjacent micro-projections. The pneumatic tire according to claim 1 or 2, wherein in the first triangular region, the raised portion is connected to all three of the adjacent micro-projections. The pneumatic tire according to claim 1 or 2, wherein the plurality of triangular regions includes a second triangular region that does not include the raised portion. The pneumatic tire according to claim 1 or 2, wherein the plurality of triangular regions includes at least one group of the first triangular regions arranged adjacent to each other. The pneumatic tire according to claim 5, wherein the plurality of triangular regions are arranged in a regular pattern in the plurality of groups. Each of the plurality of triangular regions has three imaginary sides respectively connecting the three small protrusions to each other,
each of the three imaginary sides is adjacent to any of the plurality of triangular regions;
The pneumatic tire according to claim 6 , wherein at least one of the three imaginary sides of the first triangular region is adjacent to another of the first triangular regions. The pneumatic tire according to claim 7, wherein, in a plan view of the reference plane, the first triangular region located at the end of the group is adjacent to another of the first triangular regions at one of the three imaginary sides. The pneumatic tire according to claim 7, wherein, in a plan view of the reference plane, the first triangular region located excluding the end of the group is adjacent to other first triangular regions at two of the three imaginary sides. The pneumatic tire according to claim 1 or 2, wherein 20% to 80% of the plurality of triangular regions are the first triangular region. The pneumatic tire according to claim 1 or 2, wherein the micro-projections are frustum-shaped. The diameter of the tip of the microprojection is 0.05 to 0.5 mm;
The protruding height of the minute protrusion from the reference surface is 0.1 to 1.0 mm;
The pneumatic tire according to claim 11, wherein an angle between a generatrix of the small projection and a bottom surface is 5 to 75 degrees. The pneumatic tire according to claim 1 or 2, wherein the protruding height of the raised portion is 0.05 mm or more and less than 1.0 mm.

Images