| 摘要 |
PROBLEM TO BE SOLVED: To provide a polyester fiber that has excellent spinnability, holds mechanical characteristics of a fiber, and also has superior cation dyeability and fire retardancy.SOLUTION: A polyester conjugate fiber is formed by conjugating two types of polyester of polyester A and polyester B. The polyester A is polyester in which a phosphorus compound is kneaded, and the polyester B is polyester in which 0.5-5.0 mol% of a sulfonate group-containing isophthalic acid component is copolymerized based on a total acid component of the polyester. A content of a phosphorus atom in the whole fiber is 1,000-20,000 ppm. Both of the polyester A and the polyester B have such a shape as to be exposed onto the surface. |
