Production of coated paper utilizing aqueous coatings containing particulate filler and resins having an affinity for water and utilizing nonequilibrium moisture conditions and shearing forces

Claim 1

A METHOD FOR THE CONTINUOUS PRODUCTION OF COATED PAPER TO OBTAIN ONE OR MORE OF SUPERIOR LEVELNESS, IMPROVED COATING DISTRUBITION AND SUPERIOR GLOSS AT LOWER COATING WEIGHTS COMPRISING PROVIDING A DRY FIBROUS CELLULOSIC PAPER SUBSTRATE HAVING ON ONE SURFACE THEREOF, A WATER-WET LAYER OF FROM 70-97% BY WEIGHT OF FINELY DIVIDED SOLID PARTICULATE MINERAL FILLER IN INTIMATE ADMIXTURE WITH FROM 3-30% BY WEIGHT OF HEAT-SOFTENABLE RESIN SELECTED FROM THE GROUP CONSISTING OF RESINS AT LEAST PARTIALLY SOLUBLE IN WATER AND RUBBERY LATEX PARTICLES, RAPIDLY HEATING SAID WET LAYER ON SAID PAPER SUBSTRATE UNTIL THE EXPOSED SURFACE OF THE COATED PAPER HAS A SURFACE TEMPERATURE IN THE RANGE OF FROM ABOUT 160*F. TO ABOUT 195*F., SO THAT VAPORIZATION OF IMMEDIATELY AVAILABLE SURFACE WATER IS SUFFICIENT TO BREAK THE CONTINUITY OF THE FILM OF WATER AT THE SURFACE WITHOUT UNDULY REDUCING THE AVAILABILITY OF WATER NEAR THE SURFACE OF THE COATING WHEREBY THE WATER CONTENT OF SAID WET LAYER IS SUBSTANTIALLY CONFINED TO THAT PORTION OF SAID SUBSTRATE IMMEDIATELY UNDERLYING SAID LAYER, AND PASSING SAID PAPER SUBSTRATE IN THE NON-EQUILIBRIUM MOISTURE CONDITION SPECIFIED THROUGH THE NIP BETWEEN A PAIR OF TURNING ROLLS, AT LEAST ONE OF WHICH HAS A HEATED FINISHING SURFACE, WITH SAID LAYER INCONTACE WITH SAID FINISHING SURFACE, SAID TURNING ROLLS APPLYING SUFFICIENT HEAT AND PRESSURE TO SOFTEN SAID RESIN AND TO SHEAR SAID LAYER TO DISTRIBUTE THE SAME AND SELECTIVELY DENSIFY THE PORTION OF SAID SUBSTRATE UNDERLYING SAID LAYER TO PROVIDE THE DESIRED COATED PAPER.

Claim 2

A METHOD FOR THE CONTINUOUS PRODUCTION OF COATED PAPER TO OBTAIN ONE OR MORE OF SUPERIOR LEVELNESS, IMPROVED COATING DISTRUBITION AND SUPERIOR GLOSS AT LOWER COATING WEIGHTS COMPRISING PROVIDING A DRY FIBROUS CELLULOSIC PAPER SUBSTRATE HAVING ON ONE SURFACE THEREOF, A WATER-WET LAYER OF FROM 70-97% BY WEIGHT OF FINELY DIVIDED SOLID PARTICULATE MINERAL FILLER IN INTIMATE ADMIXTURE WITH FROM 3-30% BY WEIGHT OF HEAT-SOFTENABLE RESIN SELECTED FROM THE GROUP CONSISTING OF RESINS AT LEAST PARTIALLY SOLUBLE IN WATER AND RUBBERY LATEX PARTICLES, RAPIDLY HEATING SAID WET LAYER ON SAID PAPER SUBSTRATE UNTIL THE EXPOSED SURFACE OF THE COATED PAPER HAS A SURFACE TEMPERATURE IN THE RANGE OF FROM ABOUT 160*F. TO ABOUT 195*F., SO THAT VAPORIZATION OF IMMEDIATELY AVAILABLE SURFACE WATER IS SUFFICIENT TO BREAK THE CONTINUITY OF THE FILM OF WATER AT THE SURFACE WITHOUT UNDULY REDUCING THE AVAILABILITY OF WATER NEAR THE SURFACE OF THE COATING WHEREBY THE WATER CONTENT OF SAID WET LAYER IS SUBSTANTIALLY CONFINED TO THAT PORTION OF SAID SUBSTRATE IMMEDIATELY UNDERLYING SAID LAYER, AND PASSING SAID PAPER SUBSTRATE IN THE NON-EQUILIBRIUM MOISTURE CONDITION SPECIFIED THROUGH THE NIP BETWEEN A PAIR OF TURNING ROLLS, AT LEAST ONE OF WHICH HAS A HEATED FINISHING SURFACE, WITH SAID LAYER INCONTACE WITH SAID FINISHING SURFACE, SAID TURNING ROLLS APPLYING SUFFICIENT HEAT AND PRESSURE TO SOFTEN SAID RESIN AND TO SHEAR SAID LAYER TO DISTRIBUTE THE SAME AND SELECTIVELY DENSIFY THE PORTION OF SAID SUBSTRATE UNDERLYING SAID LAYER TO PROVIDE THE DESIRED COATED PAPER.