The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 21, 1989
Filed:
Nov. 30, 1988
Herbert Beneke, Castro-Rauxel, DE;
Siegfried Peter, Uttenreuth-Weiher, DE;
Rutgerswerke AG, , DE;
Abstract
In a process for the production of carbon fibers from high boiling bituminous substances in which a purified and polymerized concentrated carbon fiber precursor is spun into fibers which are oxidized and then carbonized and optionally graphitized, the improvement comprising just before spinning a supercritical gas is dissolved in mesophase pitch at a pressure of 100 to 350 bars and a temperature up to 150.degree. K. below the melting temperature of the mesophase pitch to form a low viscosity melt, separating the latter into an isotropic phase and an anisotropic carbon fiber precursor and spinning the latter into fibers whereby the spinning temperature is lowered and the mesophase contact is increased due to the viscosity lowering activity of the supercritical gas.