Back to results
US 4,303,631 AGranted
Process for producing carbon fibers
AssigneeUnion Carbide Corporation
InventorsRichard T. Lewis, Irwin C. Lewis
Life of this patent
Estimating the term…
Abstract
A process for producing a carbon fiber features converting a precursor material under atmospheric pressure with heat but without sparging to a predetermined mesophase containing pitch, and thereafter continuing the heat treatment with sparging.
Claims20
A process for producing a carbon fiber, comprising the steps of converting a selected precursor material into a mesophase pitch, spinning the mesophase pitch into at least one pitch fiber, and converting the pitch fiber into a carbon fiber;
- wherein the improvement comprises:
- converting said precursor material into a mesophase containing pitch by a first heat treatment of said precursor material with agitation but without sparging at about atmospheric pressure in a non-reactive gaseous environment until a preliminary pitch having a mesophase content from about 20% to about 50% by weight is obtained;
- and
- thereafter, a second heat treatment of said preliminary pitch at about atmospheric pressure with both agitation and sparging with a non-reactive gas until a mesophase pitch having a mesophase content of at least 70% by weight is obtained.
1 more element
A process for producing a mesophase pitch, comprising the steps of:
- converting a selected precursor material into a preliminary pitch by a first heat treatment material with agitation but without sparging at about atmospheric pressure in a non-reactive gaseous environment until said preliminary pitch having a mesophase content from about 20% to about 50% by weight is obtained;
- and
- thereafter, a second heat treatment of said preliminary pitch at about atmospheric pressure with both agitation and sparging with a non-reactive gas until a mesphase pitch having a mesophase content of at least 70% by weight is obtained.
Dependencies are inferred from the claim text.