Patent ID: 8923674

Claim:
An optical fiber comprising: a glass fiber; and a coating surrounding the glass fiber, wherein the coating is laid on the glass fiber along a radial direction from a central axis of the optical fiber and comprises an inside coating layer and an outside coating layer surrounding the inside coating layer, wherein the inside coating layer is comprised of an ultraviolet curable resin or thermosetting resin which has a swelling rate with a plasticizer for polyvinyl chloride resin, wherein the outside coating layer is comprised of an ultraviolet curable resin or thermosetting resin which has a swelling rate with a plasticizer for polyvinyl chloride resin, wherein the swelling rate of the inside coating layer is smaller than the swelling rate of the outside coating layer, and wherein the plasticizer contains at least any one of phthalate, dioctyl phthalate, diisononyl phthalate, diisodecyl phthalate, dibutyl phthalate, adipate, dioctyl adipate, diisononyl adipate, trimellitate, trioctyl trimellitate, phosphate, tricresyl phosphate, citrate, acetyl tributyl citrate, epoxidized oil, epoxidized soybean-oil, epoxidized linseed-oil, sebacate, and azelate.