| abstract |
Individual glass fibers are coated with a composition which includes the Mannich reaction product of substitutable dihydric or trihydric phenol, formaldehyde and a primary or secondary amine. The preferred coating composition comprises an aqueous mixture including the aforementioned Mannich reaction product or an acid adduct thereof and an elastomeric latex selected from the natural and synthetic rubber latices such as neoprene rubber, isoprene rubber, butyl rubber, butadiene-styrene copolymer rubber, acrylonitrile-butadiene-styrene terpolymer rubber, styrene-butadiene-vinylpyridine terpolymer rubbers and the like. An aqueous solution of the coating composition is prepared and applied to glass fibers as a sizing composition and/or as a coating composition after the glass fibers are sized. Subsequent to coating of the glass fiber strands with the aforementioned coating composition, the strands are dried by heating in a microwave oven, a forced air oven or the like. |