PROCESS FOR IMPREGNATING A PLANAR COMPRESSIBLE CARRIER MATERIAL WITH SYNTHETIC RESIN, AS WELL AS DEVICE FOR WORKING THIS PROCESS

摘要

Sheets of base material having gurley more than 1.0 s are impregnated with synthetic resin for the prodn. of flat laminates. A coating of liq. resin, with resin content 70-100%, is first applied to one surface and heated before and/or afterwards so as to sink into the material; mechanical pressure is applied to force the coating uniformly into the material. Web of pref. paper is passed through an impregnating device where a high-viscosity resin is applied uniformly over the whole width. Resin is e.g. aq. phenolic soln. with 82 wt.% resin content and viscosity 100,000 mPa.s at 23 deg.C. Coated paper passes through an infra-red oven and heated to 70-115 deg.C and its resin sinks into the base. Material then moves between rollers heated to 125 deg.C which compress it so that the resin completely fills its pores. The material recovers thickness on emerging from the rollers but its resin remains uniformly distributed through the paper. It can be cooled next before reeling, or cut up and stacked ready for pressing.