Roll Saturation of Glass Fabric With Impregnating Varnish
Original Publication Date: 1985-Jul-01
Included in the Prior Art Database: 2005-Feb-19
This article describes a process whereby the air bubbles in epoxy/glass prepreg can be reduced or eliminated by presaturating the entire roll of fabric for 1-2 hours in impregnating varnish. The wet roll can then be positioned on the treater for further saturation (if necessary), thickness control and B-staging (partial curing of impregnating varnish). The process sequence is as follows: 1. Saturate the roll by immersing it in a holding tank. The following options for accomplishing this are: a. Use the perforated core to allow the center of the roll to saturate. b. Force the varnish through the core to wet from the inside out. c. Apply vacuum before introducing the resin into the tank. d. Apply pressure to force the solution into the evacuated area. e.