DTY is also called fiber-matrix composite fiber, which is formed by embedding one polymer in a very fine form (island phase) in another polymer (Marine phase). Because the distributed phase fibrol shows island state in the fiber section and the continuous phase matrix shows sea state, it is vividly called island fiber.
DTY is distributed in the form of an island, and the polymer of the two components is continuously dense and evenly dispersed in the longitudinal direction of the fiber. From the perspective of the whole fiber, it has the linear density and length of conventional fiber. When the soluble sea component is dissolved away, you get a superfine fibril bundle.