For example, DuPont created the highly coiled elastic fiber called cantrese having two different nylon polymers side-by-side.
[6] Formats of bicomponent fibers include:[6] Extrusions are side-by-side within a single filament Extrusions with one material surrounding another Segmented like sections of a pie Islands-in-the-sea extrusions are also called matrix-fibril, because fibrils of one polymer are distributed in the matrix of another polymer.
[7] The matrix is a soluble material that is washed away by a suitable solvent at some point in the manufacturing process.
What remains at the microscopic level are bundles of thin parallel fibers, resulting in a fabric that is very soft and flexible.
Islands-in-the-sea can be melt blown to produce fabric such as Alcantara.