Precursor fiber bundle for production of a carbon fiber bundle, a process for producing the precursor fiber bundle, a carbon fiber bundle, and a process for producing the carbon fiber bundle

摘要

A separable tow of elongated polymeric filaments comprises a plurality of distinct sub-tows lightly and individually and separably joined, as by light crimping together along their edges or, if uncrimped, joined by presence of moisture, and capable of being packed into a container and later removed and separated. The filaments are preferably acrylic and have a total fineness of about 300,00-1,500,000 denier and the sub-tows each of which has a total fineness of about 50,000-250,000 denier, with a filament fineness of about 1-2 denier, and each sub-tow has a degree of entanglement of about 10-40 m¹ as measured by the hook drop test.;The separable tow is made of a plurality of sub-tows, after separately drawing the sub-tows and subsequently removably joining the sub-tows into a single tow.