Process of coating paper with a gellable water-soluble cellulose derivative and pigment and gelling said coating

Claim 1

THE PROCESS FOR PREPARING A COATED PAPER OF THE TYPE HAVING A BASE OF CELLULOSIC FIBERS AND A PRINTING SURFACE CONSISTING ESSENTIALLY OF A FILM OF CONTIGUOUS PIGMENT PARTICLES INTERSPERSED IN BINDER BY MEANS OF WHICH THE PIGMENT IS RETAINED ON THE BASE, COMPRISING APPLYING TO THE SURFACE OF A WEB OF CELLULOSIC FIBERS A COATING COLOR CONSISTING ESSENTIALLY OF A PIGMENT DISPERSED IN AN AQUEOUS SOLUTION OF A GELLABLE WATER-SOLUBLE SODIUM SULFOETHYL CELLULOSE AS THE BINDER, SAID COATING COLOR HAVING FROM ABOUT 30% TO ABOUT 65% TOTAL SOLIDS AND HAVING SAID BINDER PRESENT IN THE AMOUNT OF BETWEEN ABOUT 5% AND ABOUT 15% BASED ON THE WEIGHT OF THE PIGMENT, AND AFTER APPLICATION OF SAID COATING COLOR COAGULATING SAID WATERSOLUBLE SODIUM SULFOETHYL CELLULOSE BY CONTACTING SAID COATING COLOR WITH A WATER SOLUTION OF SETTING AGENT SELECTED FROM THE GROUP CONSISTING OF THE MONO- AND DIALKALI METAL PHOSPHATES AND THE WATE-SOLUBLE HALIDES AND NITRATES OF THE ALKALI METALS, THE ALKALINE EARTH METALS, MAGNESIUM, AND ZINC, SQUEEZING OFF THE EXCESS SOLUTION, AND THEN DRYING THE PAPER.