Process for making spun yarn

A process for making a three-component spun yarn comprising the steps of:

• forming a first tow from a plurality of heat-resistant filaments;
• forming a second tow from a plurality of heat-resistant filaments and a plurality of filaments composed of an electrically conductive carbon black core with a sheath of a non-conductive polymer;
• and wherein the denier of the filaments having the electrically conductive carbon black core is no greater than 2.5 times the denier of the heat-resistant filaments from either tow;
• crimping these tows separately, wherein each tow has between 3 and 6 crimps per centimeter (7.6 to 15.2 crimps per inch);
• combining the tows and cutter blending the tows to form an intimate three-component blend of staple fibers;
• carding and forming a sliver of the three-component blend of staple fibers;
• spinning the sliver into spun yarns with spinning techniques which use a fluid to twist the fibers and wherein the sliver is spun at speeds in excess of 70 meters per minute.

A process for making a three-component spun yarn including the steps of:

• forming a plurality of first component filaments each having an electrically conductive carbon black core and a sheath of a non-conductive polymer into a first component yarn;
• forming a plurality of second component filaments of non-conductive poly(p-phenylene terephthalamide) into a second component yarn;
• forming a plurality of third component filaments of poly(m-phenylene isophthalamide) into a third component yarn;
• and wherein the denier of the filaments of the first component yarn is no greater than about 2.5 times the deniers of the filaments of the second and third yarns;
• combining the first and second component yarns into a first tow;
• crimping the first tow, wherein such tow has between 3 and 6 crimps per centimeter (7.6 and 15.2 crimps per inch);
• forming the third component yarn into a second tow;
• crimping the second tow, wherein such tow has between 3 and 6 crimps per centimeter (7.6 to 15.2 crimps per inch);
• combining the crimped first and second tows;
• cutter blending the combined tows to form an intimate three-component blend of staple fibers;
• forming the blend of staple fibers into a sliver;
• spinning the sliver using air spinning techniques to twist the fibers to form a spun yarn suitable for use in making permanently antistatic fabrics and wherein the sliver is spun at speeds in excess of 70 meters per minute.