Process for impregnating paper while partially dry with a quaternized resin polyelectrolyte and a clay coating

Claim 1

A METHOD OF MANUFACTURING CONDUCTIVE BACKING PAPER FOR RECORDING ELEMENTS FOR USE IN WET DEVELOPMENT ELECTROSTATIC REPRODUCTION PROCESSES AND THE LIKE, COMPRISING (A) HIGHLY REFINING A FURNISH OF PAPERMAKING FIBERS TO A SUBSTANTIALLY LOW VALUE OF FREENESS IN THE RANGE OF APPROXIMATELY 250 TO 400 CC. SCHOPPER RIEGLER; (B) FORMING ON A PAPER MACHINE A WEAK WET WEB FROM SAID FURNISH OF HIGHLY REFINED FIBERS; (C) REDUCING THE MOSITURE CONTENT IN SAID WEB AFTER FORMATION ON THE PAPER MACHINE BY A PARTIAL DRYING THEREOF; (D) IMPREGNATING AT LEAST ONE SURFACE OF SAID WEB WITH A SOLUTION OF WATER SOLUBLE QUANTERNIZED RESIN POLYELECTROLYTE IN A MANNER TO PROVIDE SAID WEB WITH NOT SUBSTANTIALLY MORE THAN APPROXIMATELY 5%, BASED UPON THE DRY SOLIDS WEIGHT OF SAID PAPERMAKING FIBERS OF SAID RESN POLYELECTROLYTE; (C) FURTHER REDUCING THE MOISTURE CONTENT OF SAID IMPREGNATED WEB OF HIGHLY REFINED FIBERS BY ADDITIONAL DRYING THEREOJF; (F) IMPREGNATING AT LEAST SAID ONE SURFACE OF SAID WEB WITH A CLAY COATING NOT IN SUBSTANTIAL EXCESS OF 10% OF THE DRY SOLIDS WEIGHT OF SAID PAPERMAKING FIBERS WHILE SUBJECTING SAID WEB TO ROLLING PRESSURE, WHEREBY THE HIGHLY REFINED FIBERS AND THE CLAY COATING COMBINE TO PROVIDE SUBSTANTIAL HOLDOUT OF SUBSEQUENTLY APPILED ELECTROSTATIC SENSITIVE COATINGS AT ONE OF THE SURFACES OF SAID WEB AND TO PROVIDE SUBSTANTIAL HOLDOUT OF SOLVENTS USED WITH ELECTROSTATIC DEVELOPMENT TONERS AT THE OTHER SURFACE OF SAID WEB; (G) THEREAFTER COMPLETELY DRYING SAID IMPREGNATED WEB OF HIGHLY REFINED FIBERS.