Patent ID: 8491725

Claim:
A cleaning method of a coloring device of an optical fiber, the coloring device having a nipple, a first die, and a second die through which the optical fiber is sequentially passed, and a frame having an ink pool formed between an external periphery of the nipple and the frame while having an ink supply opening and a cleaning-liquid discharge opening linked to the ink pool, an ink flow path being formed among the nipple and the first and the second dies, and an optical fiber passing hole of the second die having a tapered part with an internal diameter that reduces toward a passing direction of the optical fiber, the cleaning method comprising: a first cleaning which includes supplying a first cleaning-liquid to the coloring device through an optical fiber passing hole of the nipple and through the ink supply opening, and flowing a portion of the first cleaning-liquid out of the coloring device through the cleaning-liquid discharge opening while blocking a flow of the first cleaning-liquid out of the coloring device through the optical fiber passing hole of the second die; and a second cleaning which includes supplying a second cleaning-liquid to the coloring device through the optical fiber passing hole of the nipple and through the ink supply opening, and flowing a portion of the second cleaning-liquid out of the coloring device through the optical fiber passing hole of the second die.