Abstract: A water soluble sizing for fibrous carbonaceous material consists of either 1,3-diglycidyl-5,5-dimethylhydantoin or 1,3-diglycidylhydantoin. The carbonaceous material is sized by immersion in an aqueous solution of the sizing having a concentration of 0.1-10%, preferably 1-2%, by weight, followed by drying. In addition to being highly water soluble, non-toxic and non-flammable, the sizing provides excellent filament control so as to minimize fuzzing during subsequent handling of the carbonaceous material and is compatible with an epoxy resin matrix system.

Abstract: A finish composition for fibrous material such as carbon, graphite or silica fibers comprises an aqueous emulsion of an elastomer and a lubricious substance which are both dispersed in the aqueous emulsion. The elastomer comprises a latex of butyl rubber or butadiene/nitrile type rubbers, and the lubricious substance comprises an emulsion of a hydrocarbon type wax such as paraffin. The aqueous emulsion which includes a dispersant such as water proportioned to provide the emulsion with a solids concentration of up to about 1% is applied as a size to the fibrous material, following which the water is driven off such as by use of elevated temperatures to cause the lubricious substance to separate from the elastomer and exude to the surface of the elastomeric sheath surrounding the fibrous material. The finish may be used as an aid to weaving, in which event it is applied to fibers such as carbon or graphite fibers prior to weaving and then removed after the weaving is completed.