Abstract: Chopped carbon yarn is produced by spinning continuous pitch yarn, treating the pitch yarn with an oxidizing composition, chopping the pitch yarn into short lengths, collecting the chopped pitch yarn into a bulk form, and subjecting the chopped pitch yarn to a heat treatment in a substantially non-reactive atmosphere to produce chopped carbon yarn.

Abstract: A bobbin capable of retaining thermoset yarn during a heat treatment to pyrolyze and carbonize the thermoset yarn to produce a good quality carbon yarn, comprises a cylindrical body made of selected materials; and a layer of carbon felt positioned on the outside surface of the cylindrical body to receive the thermoset yarn and to minimize stress between the cylindrical body and the thermoset yarn during the heat treatment.

Abstract: A method for producing a mesophase pitch derived carbon yarn features collecting thermoset mesophase pitch yarn onto a bobbin, and subjecting the thermoset yarn to a heat treatment in an inert atmosphere to pyrolyze and carbonize the thermoset yarn.

Abstract: Fibers having a high degree of flexibility and handleability are produced by oxidizing fibers spun from a carbonaceous pitch which has been transformed, in part, to a liquid crystal or so-called "mesophase" state to an oxygen content of from 17 per cent by weight to 30 per cent by weight. Because of their strength and handleability, these highly-oxidized fibers can be easily processed at high speeds by means of conventional yarn-transport systems, and readily woven or knit into cloth. Such cloth may then be heat treated to produce carbon or graphite cloth.