Patent ID: 7955539

Claim:
A method of making a reversed, heat-set elastic fiber comprising: (a) applying a biasing force to an elastic fiber that will recover at least 50% of its stretched length after the first pull and after the fourth pull of four consecutive pulls to 100% strain, wherein the elastic fiber is a melt spun elastic fiber; (b) heating the stretched fiber of (a) to a temperature in excess of a temperature at which at least a portion of the crystallites are molten; (c) cooling the fiber of (b) to a temperature below the temperature of step (b); (d) removing the biasing force from the fiber; and thereafter (e) heating the temperature of the fiber above a temperature at which at least a portion of the crystallites are molten without a biasing force, such that the length of the fiber obtained in step (e) is less than the length of the fiber obtained in step (d).