Patent ID: 7261785

Claim:
A process of forming, on an outer surface of a tire, a color-contrasting motif comprised of at least one uncured colored rubber mix, the process comprising the following steps: a) preparing an uncured blank of a tire to be molded; b) depositing uncured colored rubber in a cavity formed in at least one insert, the cavity including a subcavity delimited by a rib arrangement disposed in the cavity, wherein parts of the cavity are disposed laterally outwardly of the rib arrangement, the colored rubber being color-contrasting with respect to the blank, the cavity having the general form of the color-contrasting motif to be molded and having a total volume (V 0 ), the total volume of uncured colored rubber (V 1 ) deposited in the cavity being less than the volume (V 0 ), wherein the uncured colored rubber comprises a plurality of layers of rubber of different respective colors, the layers being deposited successively one upon the other during step b such that a subsequently-deposited layer is disposed on a previously-deposited layer; thereafter c) mounting the at least one insert in a recess provided in a molding surface of a mold for the tire; d) engaging the blank within the mold; e) vulcanizing the uncured blank and the uncured colored rubber, wherein rubber of the previously-deposited layer flows within the subcavity, and rubber of the subsequently-deposited layer flows laterally outwardly past the rib arrangement and into the laterally outward parts of the cavity, as the vulcanized colored rubber forms a multi-colored motif; and f) removing the at least one insert from the motif to reveal the multiple colors which are visible to an observer of the motif.