Rubber Member, Tire, and Method of Manufacturing Rubber Member

1 . A rubber member comprising: a fine ridged/grooved structure on at least a part of a surface of the rubber member, the fine ridged/grooved structure formed via transfer from a mold and having fine ridged/grooved portions arranged at a constant arrangement pitch;

a region in which the fine ridged/grooved structure is provided being visually recognizable by a structural color different from colors of other regions.

2 . The rubber member according to claim 1 , wherein the arrangement pitch or ridge/groove height of the fine ridged/grooved portions is determined based on a wavelength of visible light, the wavelength corresponding to a color visually recognizable as the structural color.

3 . The rubber member according to claim 1 , wherein the arrangement pitch or ridge/groove height of the fine ridged/grooved portions is equal to or smaller than 650 nm.

4 . A tire made of a rubber member described in claim 1 .

5 . The tire according to claim 4 , wherein

the fine ridged/grooved structure is formed on a sidewall portion, and

the region in which the fine ridged/grooved structure is provided is formed in a shape to display predetermined information.

6 . The tire according to claim 5 , wherein

the sidewall portion contains a diene rubber, a carbon black, and a silica, and

the diene rubber contains from 30 to 70 mass % of natural rubber and/or isoprene rubber, a nitrogen adsorption specific surface area of the carbon black is from 20 to 60 m 2 /g, a content of the carbon black is from 5 to 45 parts by mass per 100 parts by mass of the diene rubber, a content of the silica is from 15 to 55 parts by mass per 100 parts by mass of the diene rubber, and a total content of the carbon black and the silica is from 30 to 60 parts by mass per 100 parts by mass of the diene rubber.

7 . A method of manufacturing the rubber member described in claim 1 , the method comprising:

forming a mask on which pattern structures are arranged at the constant pitch;

arranging the mask on a substrate made of a metal or a semiconductor material and etching the substrate; and

adhering unvulcanized rubber to the substrate, vulcanizing the unvulcanized rubber to form vulcanized rubber, and transferring the fine ridged/grooved structure to a surface of the vulcanized rubber.

8 . The method of manufacturing the rubber member according to claim 7 , further comprising determining the arrangement pitch of the fine ridged/grooved portions based on a wavelength of visible light, the wavelength corresponding to the color visually recognizable as the structural color, wherein

in the forming the mask, the pitch of the pattern structures is determined based on the arrangement pitch determined in the determining the arrangement pitch.

9 . The method of manufacturing the rubber member according to claim 7 , further comprising determining a ridge/groove height of the fine ridged/grooved portions based on a wavelength of visible light, the wavelength corresponding to the color visually recognizable as the structural color, wherein

in the etching, an etching time of the substrate is appropriately controlled to match the ridge/groove height of the ridged/grooved portions with the ridge/groove height determined in the determining the ridge/groove height.

10 . The rubber member according to claim 2 , wherein the arrangement pitch or ridge/groove height of the fine ridged/grooved portions is equal to or smaller than 650 nm.

11 . A tire made of a rubber member described in claim 10 .

12 . The tire according to claim 11 , wherein

the fine ridged/grooved structure is formed on a sidewall portion, and

the region in which the fine ridged/grooved structure is provided is formed in a shape to display predetermined information.

13 . The tire according to claim 12 , wherein

the sidewall portion contains a diene rubber, a carbon black, and a silica, and

the diene rubber contains from 30 to 70 mass % of natural rubber and/or isoprene rubber, a nitrogen adsorption specific surface area of the carbon black is from 20 to 60 m 2 /g, a content of the carbon black is from 5 to 45 parts by mass per 100 parts by mass of the diene rubber, a content of the silica is from 15 to 55 parts by mass per 100 parts by mass of the diene rubber, and a total content of the carbon black and the silica is from 30 to 60 parts by mass per 100 parts by mass of the diene rubber.

14 . A method of manufacturing the rubber member described in claim 10 , the method comprising:

forming a mask on which pattern structures are arranged at the constant pitch;

arranging the mask on a substrate made of a metal or a semiconductor material and etching the substrate; and

adhering unvulcanized rubber to the substrate, vulcanizing the unvulcanized rubber, and transferring the fine ridged/grooved structure to a surface of the vulcanized rubber.

15 . The method of manufacturing the rubber member according to claim 14 , further comprising determining the arrangement pitch of the fine ridged/grooved portions based on a wavelength of visible light, the wavelength corresponding to the color visually recognizable as the structural color, wherein

in the forming the mask, the pitch of the pattern structures is determined based on the arrangement pitch determined in the determining the arrangement pitch.

16 . The method of manufacturing the rubber member according to claim 14 , further comprising determining the ridge/groove height of the fine ridged/grooved portions based on a wavelength of visible light, the wavelength corresponding to the color visually recognizable as the structural color, wherein

in the etching, an etching time of the substrate is appropriately controlled to match the ridge/groove height of the ridged/grooved portions with the ridge/groove height determined in the determining the ridge/groove height.