Patent Publication Number: US-2020276869-A1

Title: Tire

Description:
TECHNICAL FIELD 
     The present disclosure relates to a tire at which minute projections are formed at the outer surface thereof. 
     BACKGROUND ART 
     Conventionally, pattern ons having contrast are formed by forming minute projections at the side portions of a tire. For example, International Application Publication No. 2012/131089 discloses a technique that provides large contrast at the side portions of a tire by plural projections that are formed over an entire pattern region. 
     SUMMARY OF INVENTION 
     Technical Problem 
     A decorative portion at the side portion of a tire has one region where projections are formed. By controlling the reflection of light by the projections, the brightness of this one region is low as compared with the brightness of other regions where light is reflected as is. However, the range of expression of the decorative portion where the projections are formed at a tire is limited by merely lowering the brightness of the one region, at which the projections are formed, to a similar brightness overall. 
     An object of the present disclosure is the broadening of the range of expression of a decorative portion having regions where projections are formed at a tire. 
     Solution to Problem 
     A tire relating to the present disclosure has: a decorative portion that is formed at a tire outer surface and has a base surface; and a plurality of first pattern regions at which a plurality of projections, which project out from the base surface of the decorative portion at a projecting height of from 0.1 [mm] to 1.0 [mm], are formed at intervals of from 0.1 [min] to 1.0 [mm], wherein intervals between the projections differ from one another in the plural first pattern regions. 
     Advantageous Effects of Invention 
     In accordance with the present disclosure, the range of expression of a decorative portion having regions where projections are formed at a tire can be broadened. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an enlarged side view showing a. decorative portion of a tire relating to a first embodiment in the present invention. 
         FIG. 2(A)  is a plan view showing projections that are formed at a medium brightness region of the decorative portion,  FIG. 2(B)  is a plan view showing projections that are formed at a second low brightness region of the decorative portion, and  FIG. 2(C)  is a plan view showing projections that are formed at a first low brightness region of the decorative portion. 
         FIG. 3  is an enlarged plan view showing the projections. 
         FIG. 4  is a cross-sectional view showing the projections. 
         FIG. 5  is an enlarged plan view showing the projections that are formed at the first low brightness region. 
         FIG. 6  is an enlarged side view showing a decorative portion of a tire relating to a second embodiment in the present invention. 
         FIG. 7  is a perspective view showing a decorative portion that is provided at a groove of a tread, at a tire relating to a third embodiment in the present invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     First Embodiment 
     An example of a tire  10  relating to a first embodiment in the present invention is described in accordance with  FIG. 1  through  FIG. 5 . Note that arrow C that is shown in the drawings indicates the tire circumferential direction, arrow R indicates the tire radial direction, and arrow W indicates the tire width direction. 
     As shown in  FIG. 1 , decorative portions  14  are formed at a tire side portion  12  that is an example of an outer surface of the tire  10 . The decorative portion  14  is, for example, formed in an arcuate shape as seen from the axial direction of the tire  10 , and is disposed at an arbitrary position in the tire circumferential direction. Moreover, the decorative portion  14  has a base surface  40  (see  FIG. 4 ). The base surface  40  is recessed with respect to another region  18 , which is the region other than the decorative portion  14  at the tire side portion  12  and at which projections and the like are not formed. This base surface  40  structures the bottom surface of the decorative portion  14 , and, as seen from the tire circumferential direction, is formed in the shape of a curved surface that is convex toward the outer side in the width direction of the tire  10 . In the present embodiment, the base surface  40  is recessed by 0.4 [mm] with respect to the another region  18 . 
     Moreover, a first low brightness region  21 , second low brightness regions  22 , and a third low brightness region  23 , whose brightness is low as compared with the another region  18  and that appear black, are formed at the decorative portion  14  as examples of plural first pattern regions. Thereamong, the brightness of the third low brightness region  23  is the lowest, and the brightness of the second low brightness regions  22  is the highest. The brightness of the first low brightness region  21  is lower than the brightness of the second low brightness regions  22  and higher than the brightness of the third low brightness region  23 . Further, medium brightness regions  16  are formed at the decorative portion  14  as an example of second pattern regions. The brightness of the medium brightness regions  16  is low as compared with the brightness of the another region  18 , and is high as compared with the brightness of the second low brightness regions  22 . Due thereto, the medium brightness region  16  appears gray. 
     Further, the first low brightness region  21  that is formed at the decorative portion  14  extends in the tire circumferential direction, and the second low brightness regions  22  are disposed adjacent to the tire circumferential direction both end sides of the first low brightness region  21 , respectively. Moreover, the medium brightness regions  16  are disposed adjacent to the tire circumferential direction both end sides of the second low brightness regions  22 , respectively. The third low brightness region  23  is disposed within the range of the first low brightness region  21 . In other words, the third low brightness region  23  is adjacent to the first low brightness region  21  and is surrounded by the first low brightness region  21 . 
     Note that the first low brightness region  21 , the second low brightness regions  22 , the third low brightness region  23  and the medium brightness regions  16  are formed by providing indentations and projections at portions, which correspond to the first low brightness region  21 , the second low brightness regions  22 , the third low brightness region  23  and the medium brightness regions  16 , of a mold (die) for molding the tire  10 . Further, the first low brightness region  21 , the second low brightness regions  22 , the third low brightness region  23  and the medium brightness regions  16  being disposed further toward the tire radial direction outer side than the tire maximum width portion (the portion where the rectilinear distance between the tire side portions is the maximum), is preferable from the standpoint of visibility in the state in which the tire  10  is mounted to a vehicle. 
     First asterisk projections  34  and second asterisk projections  36 , which are examples of projections, are formed so as to be similar to one another at the medium brightness region  16  shown in  FIG. 2(A) , the second low brightness regions  22  shown in  FIG. 2(B) , and the first low brightness region  21  shown in  FIG. 2(C) . Further, interval P between the first asterisk projection  34  and the second asterisk projection  36  that are adjacent to one another varies in accordance with the ratio of similitude. At the medium brightness region  16  and the second low brightness region  22  that are adjacent to one another, the ratio of the intervals P between the first asterisk projection  34  and the second asterisk projection  36  is, for example, from 1.1 to 3.0. 
     As described above, the shapes of the first asterisk projections  34  and the second asterisk projections  36  are similar at the respective regions. Accordingly, the shapes of the first asterisk projections  34  and the second asterisk projections  36  will be described by using the first low brightness region  21  as an example. 
     (First Low Brightness Region  21 ) 
     As shown in  FIG. 3 , the first low brightness region  21  has the plural first asterisk projections  34  and the plural second asterisk projections  36  that project-out from the base surface  40 . Further, the first asterisk projections  34  and the second asterisk projections  36  are disposed alternately in the tire circumferential direction and the tire radial direction. 
     [First Asterisk Projection  34 ] 
     As shown in  FIG. 3 . as seen from a direction orthogonal to the base surface  40  (from the rotation axial direction of the tire  10  ( FIG. 1 )), the first asterisk projection  34  is structured from first extending portions  35 A- 1 ,  35 A- 2 , second extending portions  35 B- 1 ,  35 B- 2 , and third extending portions  35 C- 1 ,  35 C- 2  that extend out in respectively different directions from center O 1  that is the base point. Hereinafter, these six extending portions are collectively called the “extending portions  34 E”. Further, a linear shape that is bent at the center O 1  is structured by the one extending portion  34 E and the another extending portion  34 E (except for the extending portions  34 E that extend from the center O 1  in directions opposite one another). 
     The first extending portion  35 A- 1  and the first extending portion  35 A- 2  extend out from the center O 1  in directions opposite one another, a shape that is continuous in a rectilinear form is structured by the first extending portion  35 A- 1  and the first extending portion  35 A- 2 . The first extending portion  35 A- 1  extends from the center O 1  toward the tire radial direction outer side, and the first extending portion  35 A- 2  extends from the center O 1  toward the tire radial direction inner side. Further, the first extending portion  35 A- 1  and the first extending portion  35 A- 2  are made to be similar lengths. Hereinafter, the first extending portion  35 A- 1  and the first extending portion  35 A- 2  collectively are called the “first extending portions  35 A”. 
     The second extending portion  35 B- 1  and the second extending portion  35 B- 2  extend out from the center O 1  in directions opposite one another, and a. shape that is continuous in a. rectilinear form is structured by the second extending portion  35 B- 1  and the second extending portion  35 B- 2 . The second extending portion  35 R- 1  and the second extending portion  35 B- 2  are inclined with respect to the tire circumferential direction such that the end portions at a tire circumferential direction one side (the left side in the drawing) are positioned at the tire radial direction outer side with respect to the end portions at the another side (the right side in the drawing). 
     The second extending portion  35 B- 1  extends out from the center O 1  toward the tire circumferential direction one side, and the second extending portion  35 B- 2  extends out from the center O 1  toward the tire circumferential direction another side. Further, the second extending portion  35 B- 1  is made to be long as compared with the second extending portion  35 B- 2 . Moreover, the distal end side portion of the second extending portion  353 - 2  is curved toward the tire radial direction inner side. Hereinafter, the second extending portion  35 B- 1  and the second extending portion  35 B- 2  collectively are called the “second extending portions  35 B”. 
     The third extending portion  35 C- 1  and the third extending portion  35 C- 2  extend out from the center O 1  in directions opposite one another, and a shape that is continuous in a rectilinear form is structured by the third extending portion  35 C- 1  and the third extending portion  35 C- 2 . The third extending portion  35 C- 1  and the third extending portion  35 C- 2  are inclined with respect to the tire circumferential direction such that the end portions at the tire circumferential direction one side (the left side in the drawing) are positioned at the tire radial direction inner side with respect to the end portions at the another side (the right side in the drawing). 
     The third extending portion  35 C- 1  extends out from the center O 1  toward the tire circumferential direction another side, and the third extending portion  35 C- 2  extends out from the center O 1  toward the tire circumferential direction one side. Further, the third extending portion  35 C- 1  is made to be short as compared with the third extending portion  35 C- 2 . Hereinafter, the third extending portion  35 C- 1  and the third extending portion  35 C- 2  collectively are called the “third extending portions  35 C”. 
     The six extending portions  34 E form angles of 60° respectively with the extending portions  34 E adjacent thereto. In other words, the first asterisk projection  34  is a shape in which the six extending portions  34 E extend out in a radial form from the center O 1 . 
     As shown in  FIG. 4 , at the extending portion  34 E of the first asterisk projection  34 , the cross-section in the direction orthogonal to the extending direction is a substantially isosceles triangle shape that has a flat peak surface  34 C. Namely, the first asterisk projection  34  has the peak surface  34 C and a pair of side surfaces  34 D. In the present embodiment, the width (W 1  in the drawing) of the peak surface  34 C is 0.02 [mm], and the apex angle (D in the drawing) of the first asterisk projection  34  is 26 [degrees]. Further, height (H in the drawing) of the first asterisk projection  34  is a value that is determined in advance and that is from 0.1 [mm] to 1.0 [mm]. If the height of the projections (the projecting height) is less than 0.1 [mm], molding of the projections is difficult, and there is the concern that the brightness cannot be lowered to the extent of being seen as black by damping the incident light. Moreover, by making the height of the projections less than or equal to 1.0 [mm], the difference between the rigidity of the projection portions and the rigidity of the portions at the peripheries of the projections is small, and local concentrations of stress are suppressed. 
     Note that the dimensions, such as the height of the projections and the interval (pitch) between the projections that is described later and the like, in the present embodiment are measured by using, as an example, the One-Shot 3D Measuring Macroscope VR-3000 series by Keyence Corporation. 
     [Second Asterisk Projections  36 ] 
     As shown in  FIG. 3 , the second asterisk projections  36  have shapes that are similar to those of the first asterisk projections  34 . Concretely, as seen from the direction orthogonal to the base surface  40 , the second asterisk projection  36  is a shape in which the first asterisk projection  34  is rotated 90 [degrees] clockwise around the center O 1 , and moreover, is rotated 90 [degrees] clockwise around the center O 1  so that the top and bottom of the first asterisk projection  34  are reversed. 
     At the second asterisk projection  36 , the portions that correspond to the first extending portions  35 A- 1 ,  35 A- 2 , the second extending portions  359 - 1 ,  359 - 2 , the third extending portions  35 C- 1 ,  35 C- 2  and the center O 1  of the first asterisk projection  34  are called first extending portions  37 A- 1 ,  37 A- 2 , second extending portions  37 B- 1 ,  37 B- 2 , third extending portions  37 C- 1 ,  37 C- 2  and center O 2 . Hereinafter, these six extending portions are collectively called “extending portions  36 E”. 
     Further, at the second asterisk projection  36 , the portion that corresponds to the peak surface  34 C of the first asterisk projection  34  is called a peak surface  36 C. Moreover, at the second asterisk projection  36 , the portions that correspond to the side surfaces  34 D of the first asterisk projection  34  are called side surfaces  36 D (see  FIG. 4 ). 
     [Other Points] 
     As shown in  FIG. 2(C) , the first asterisk projections  34  and the second asterisk projections  36  are disposed alternately in the tire circumferential direction and the tire radial direction, and fill-up the entire first low brightness region  21 . 
     As shown in  FIG. 3 , the respective distal ends of the first extending portions  35 A- 1 ,  35 A- 2  of the first asterisk projections  34  are inserted respectively between the second extending portions  37 B- 2  and the third extending portions  37 C- 1 , and between the second extending portions  37 B- 1  and the third extending portions  37 C- 2 , of the second asterisk projections  36  that are adjacent thereto in the tire radial direction. Further, the respective distal ends of the first extending portions  37 A- 1 ,  37 A- 2  of the second asterisk projections  36  are inserted respectively between the second extending portions  35 B- 1  and the third extending portions  35 C- 2 , and between the second extending portions  35 B- 2  and the third extending portions  35 C- 1 , of the first asterisk projections  34  that are adjacent thereto in the tire circumferential direction. 
     Moreover, the distal ends of the third extending portions  35 C- 1  of the first asterisk projections  34 , and the distal ends of the second extending portions  37 B- 1  of the second asterisk projections  36  that are disposed at the tire radial direction outer sides of the first asterisk projections  34 , are connected to one another, Connecting portions  34 A are thereby formed. Moreover, the distal ends of the second extending portions  35 B- 1  of the first asterisk projections  34 , and the distal ends of the third extending portions  37 C- 1  of the second asterisk projections  36  that are disposed at the tire circumferential direction one sides of the first asterisk projections  34 , are connected to one another. Connecting portions  34 B are thereby formed. 
     In this structure, the first asterisk projections  34  and the second asterisk projections  36  are connected to one another in the form of steps via the connecting portions  34 A,  34 B, from the tire radial direction inner side toward the outer side. 
     Further, at the first asterisk projections  34  and the second asterisk projections  36  that are adjacent to one another in the tire radial direction and the tire circumferential direction, the interval between the center O 1  and the center O 2  (hereinafter the “interval P”) is a value that is determined in advance and that is from 0.1 [mM] to 1.0 [mm]. If the interval P is less than 0.1 [mm], molding of the projections is difficult. Moreover, if the interval P is larger than 1.0 [mm], there is the concern that the brightness cannot be lowered to the extent of being seen as black by damping the incident light. Note that the interval P at the second low brightness regions  22  may be set to he greater than 0.5 [mm], within the aforementioned range. This is because the range of expression of the decorative portion  14  can be further broadened. 
     Here, at the first low brightness region  21  and the second low brightness regions  22 , which appear black and are described in the present embodiment, the value of brightness L* measured by using the Handy Spectrophotometer (NF333) of Nippon Denshoku Industries Co., Ltd. is in the region of less than 10, as an example. The range of the brightness L* is 0 to 100, and, the closer to 0, the more black the appearance, and, the closer to 100, the more white the appearance. Further, at the medium brightness regions  16  that appear gray, the value of the brightness L* is in the region of from 10 to 20, as an example. Namely, the medium brightness regions  16  that appear gray are regions whose brightness is a relatively medium level at the outer surface of the tire  10 . At the another region  18  that is other than the decorative portions  14  at the tire side portion  12 , the value of the brightness L* is greater than  20 , as an example. 
     (Third Low Brightness Region  23 ) 
     The third low brightness region  23  that is shown in  FIG. 1  expresses the alphabet letter “A” for example. As shown in  FIG. 5 , the third low brightness region  23  is structured by plural rib-shaped projections  52  that are examples of the projections. The rib-shaped projections  52  are formed as V-shaped units at the base surface  40  of the decorative portion  14 . The rib-shaped projections  52  are, for example, formed in zigzag shapes by being connected to one another in the tire circumferential direction. Further, a plurality of the zigzag rib-shaped projections  52  are formed in the tire radial direction. The cross-sectional shape of the rib-shaped projection  52  and the interval P between the center of one of the rib-shaped projections  52  and the center of another of the rib-shaped projections  52  among the rib-shaped projections  52  that are adjacent to one another, are similar to the cross-sectional shape and the interval P of the first asterisk projections  34  and the second asterisk projections  36  that are shown in  FIG. 4 . An arbitrary letter, shape, symbol, pattern or the like can be expressed by the third low brightness region  23 , within the range of the first low brightness region  21 . Further, surfaces that are orthogonal to and surfaces that are parallel to the angle of incidence of the light are formed alternately by the rib-shaped projections  52 . Due thereto, striped light and dark can be expressed at the decorative portion  14 . 
     (Medium Brightness Regions  16 ) 
     In  FIG. 2(A) , at the medium brightness regions  16 , the interval between the first asterisk projections  34  and the second asterisk projections  36  is set to be greater than 1 [mm]. 
     (Operation, Effects) 
     Operation/effects of the tire relating to the present embodiment are described next. 
     At the decorative portion  14  of the tire side portion  12 , the light that is incident on the first asterisk projections  34  and the second asterisk projections  36  that are formed at the first low brightness region  21 , the second low brightness regions  22  and the third low brightness region  23  hits the side surfaces  34 D,  36 D that are shown in  FIG. 4 . Further, the incident light is damped while reflecting thereof is repeated between the side surfaces  34 D,  36 D that face one another, and is reflected to the outer side. 
     Further, at the medium brightness regions  16  of the decorative portion  14  of the tire side portion  12 , the light that is incident on the first asterisk projections  34  and the second asterisk projections  36  that are formed at the medium brightness regions  16  also similarly is damped while reflecting thereof is repeated between the side surfaces  34 D,  36 D that face one another, and is reflected to the outer side. 
     Moreover, at the another region  18  where the projections are not formed of the tire side portion  12 , the light that is incident on the another region  18  is reflected to the outer side by the outer surface that structures the another region  18 . 
     Here, the interval P between the first asterisk projections  34  and the second asterisk projections  36  that are formed at the first low brightness region  21  and the second low brightness regions  22 , and the interval P between the rib-shaped projections  52  that are formed at the third low brightness region  23 , are respectively values that are determined in advance and that are from 0.1 [mm] to 1.0 [mm]. In these low brightness regions, the brightness is low as compared with at the another region  18  where projections are not formed. Further, at the respective low brightness regions, because the intervals between the projections differ from one another, the brightnesses are gradually varied, and gradation can be expressed. At at least one of the low brightness regions, due to the interval P between adjacent projections being made to be greater than 0.5 [mm], the brightness can be made to be bright as compared with at regions where the interval between adjacent projections is less than or equal to 0.5 [mm]. In this way, the range of expression of the decorative portion  14  that has regions where projections are formed at the tire  10  can be broadened. 
     Further, the interval P between the first asterisk projection  34  and the second asterisk projection  36  that are formed at the medium brightness regions  16  is a value that is set in advance and that is greater than 1.0 [mm]. Namely, the density of the projections that are formed at the medium brightness regions  16  is low as compared with the densities of the projections that are formed at the first low brightness region  21 , the second low brightness regions  22  and the third low brightness region  23 . 
     Moreover, because the apex angles of the respective projections are similar, the regions, which the base surface  40  occupies per unit surface area at the medium brightness regions  16 , is large as compared with the regions that the base surface  40  occupies per unit surface area at the first low brightness region  21 , the second low brightness regions  22  and the third low brightness region  23 . 
     Due thereto, the amount of light that is reflected to the outer side at the medium brightness regions  16  is large as compared with the amounts of light that are reflected to the outer side at the first low brightness region  21 , the second low brightness regions  22  and the third low brightness region  23 . Moreover, the amount of light that is reflected to the outer side at the medium brightness regions  16  is small as compared with the amount of light that is reflected to the outer side at the another region  18  at which projections are not formed. Namely, the brightness L* of the third low brightness region  23 , the first low brightness region  21 , the second low brightness regions  22 , the medium brightness regions  16  and the another region  18  become higher in that order. 
     Therefore, the first low brightness region  21 , the second low brightness regions  22  and the third low brightness region  23  appear black relatively, and the another region  18  appears white relatively, and the medium brightness region  16  appears gray relatively. Due thereto, the brightness is gradually varied in stages, and better gradation can be expressed. Further, at the second low brightness region  22  and the medium brightness region  16  that are adjacent to one another, by setting the ratio of the intervals P of the projections to be from 1.0 to 3.0, the gradual variation in the brightness is easy to see. 
     By providing the medium brightness regions  16  in addition to the first low brightness region  21 , the second low brightness regions  22  and the third low brightness region  23 , the range of expression of the decorative portion  14  can be broadened as compared with a case in which only the above-described low brightness regions are formed. In other words, the manners of expression can be increased. 
     Further, in  FIG. 3 , the respective extending portions  34 E of the first asterisk projections  34  extend in different directions, and the respective extending portions  36 E of the second asterisk projections  36  extend in different directions Due thereto, even when the decorative portion  14  is viewed while the angle of viewing thereof is changed, the appearance differing can be suppressed. 
     Further, the first asterisk projections  34  are structured by the extending portions  34 E that extend out in respectively different directions and six of which are connected at the center O 1 . The second asterisk projections  36  are structured by the extending portions  36 E that extend out in respectively different directions and six of which are connected at the center  02 . Accordingly, it is difficult for the first asterisk projections  34  and the second asterisk projections  36  respectively to collapse, and the durability of the first asterisk projections  34  and the second asterisk projections  36  respectively can be improved. 
     Further, the first asterisk projections  34  and the second asterisk projections  36  are connected in the form of steps via the connecting portions  34 A,  34 B. Due thereto, the first asterisk projections  34  and the second asterisk projections  36  support one another via the connecting portions  34 A,  34 B, and collapsing-in of the first asterisk projections  34  and the second asterisk projections  36  is suppressed. Therefore, the durability can be improved. 
     Second Embodiment 
     In  FIG. 6 , at a tire  20  relating to a second embodiment in the present invention, the first low brightness regions  21  and the second low brightness regions  22  that are formed in rectangular shapes are disposed in series respectively in the form of steps, in directions intersecting the tire radial direction. Further, the first low brightness regions  21  and the second low brightness regions  22  are disposed alternately in the tire circumferential direction. A zigzag pattern can be seen at the decorative portion  14  due to the difference in brightnesses between the first low brightness regions  21  and the second low brightness regions  22 . 
     Operation of the second embodiment, and the detailed structures of the first low brightness regions  21  and the second low brightness regions  22 , are similar to the first embodiment, and therefore, description thereof is omitted. 
     Third Embodiment 
     In  FIG. 7 , at a tire  30  relating to the third embodiment in the present invention, the decorative portion  14  is formed at a tread  32  of the tire  30 . Concretely, plural circumferential direction grooves  42 ,  44  that extend in the tire circumferential direction are formed in the tread  32  of the tire  30  so as to be apart in the tire width direction (arrow W in the drawing). The circumferential direction groove  42  is provided at the tire width direction central portion, and the circumferential direction grooves  44  are provided at the tire width direction both sides of the circumferential direction groove  42 , respectively. The decorative portion  14  is formed at the circumferential direction groove  42  that is at the tire width direction central portion and serves as an example of the tire outer surface. At the decorative portion  14 , the first low brightness regions  21  and the second low brightness regions  22 , which serve as examples of plural first patterns, are disposed alternately in the tire circumferential direction for example. In this way, by providing the decorative portion  14  at the circumferential direction grooves  44 . the range of expression at the tread  32  can be broadened. 
     Note that a second pattern region may be provided in addition to the first pattern region. Further, the arrangement of the respective pattern regions is arbitrary. The respective pattern regions may be lined-up, for example, in the tire width direction, or in an inclined direction that intersects the tire width direction. 
     The detailed structures of the first low brighmess regions  21  and the second low brightness regions  22  are similar to the first embodiment, and therefore, description thereof is omitted. 
     Other Embodiments 
     Note that embodiments relating to the present invention are not limited to the above-described respective embodiments, and it will be clear to those skilled in the art that various other embodiments are possible within the scope of the present invention. For example, in the above-described first embodiment, the first asterisk projections  34  and the second asterisk projections  36  are connected to one another, but may be structured so as to not be connected to one another. Further, although the third low brightness region  23  is provided as the second pattern region, such a second pattern region does not have to be provided. 
     The apex angles of the projections such as the first asterisk projections  34  and the second asterisk projections  36  and the like (e.g., D in  FIG. 4 ) are 26 [degrees], but may be another angle, if the apex angle D is large, the proportion of the reflected light, which is reflected at the side surfaces  34 D,  36 D, that returns in the incident direction is large, and the brightness L* is relatively higher. 
     The disclosure of Japanese Patent Application No. 2017-236451 filed on Dec. 8, 2017 is, in its entirety, incorporated by reference into the present specification. All publications, patent applications, and technical standards mentioned in the present specification are incorporated by reference into the present specification to the same extent as if such individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.