Process of preparing fibrous sheet from high-ortho phenolic resole resin varnish

A process for preparing a resin impregnated sheet which comprises:

• A. preparing a resole resin by reacting a phenol selected from the group consisting of phenol, meta-substituted phenol and a mixture of phenol and at least one substituted phenol with formaldehyde in an aqueous reaction mixture containing at least 14 weight percent water under reflux at about 60.degree. C. to 100.degree. C. in the presence of a divalent electropositive metal ion and sufficient organic acid to maintain a pH in the range between about 4 and 7, and thereafter dehydrating the resulting aqueous emulsion to a water content of from about 0.5 to 15 weight percent,
• B. dissolving the resole resin in a volatile inert organic solvent to yield a solution of between 20 and 85 weight percent solids and a viscosity in the range of 5 to 500 centipoises,
• C. impregnating a fibrous sheet substrate with the resole resin solution to provide a fibrous sheet substrate containing from about 15 to 70 weight percent of the resole resin,
• D. drying the impregnated fibrous sheet substrate to reduce the volatile content, and
• E. advancing the resin to the B-stage.