Method for making filament reinforced a-stage profiles

摘要: Fiberglass filament unwound from a series of spools is impregnated with resin matrix and passed through pair rollers or sizing bushing for removing the excess air therefrom. The fiberglass then envelopely enclosed within sheet unidirectionally oriented plastic film, latter being sealed along its upper longitudinal margin by means an ultrasonic weld heat weld. film composite may be heated to shrink film. temperature should sufficiently low have no curing effect on leaving it in uncured so-called ''''A-stage.'''' For some systems, desirable advance semicured ''''B-stage.'''' wound upon suitable reels stored further use.