Filler for paper and method of making the same

Claim 1

THE METHOD OF MAKING, FOR USE IN THE MANUFACTURE OF PAPER, AN ALUMINUM SILICATE FILLER, WHICH METHOD COMPRISES BLENDING AN ALUMINUM SALT OF A STRONG, COMMON, MINERAL ACID WITH WATER IN SUITABLE PROPORTIONS TO FORM A SOLUTION CHARACTERIZED BY A PH OF LESS THAN FOUR, PROGRESSIVELY ADDING A SOLUTION OF SODIUM SILICATE DIRECTLY TO THE ALUMINUM SALT SOLUTION UNER HIGH SHEAR AGITATION TO FORM AN ALUMINUM SILICATE PRECIPITATE, THE SODIUM SILICATE BEING ADDED AT A RATE SIFFUCIENTLY RSTRICTED IN RELATION TO THE DEGREE OF SHEAR AGITATION MAINTAINED TO AVOID THE FORMATION OF A LUMPY PRECIPATE, AND PROGRESSIVELY ADDING SODIUM HYDROXIDE WITH A PORTION AT LEAST OF TFTHE SODIUM SILICATE, THE TOTAL QUANTITY OF SODIUM HYDROXIDE ADDED BEING SUFFICIENTLY GREAT TO ASSURE THE SUBSTANTIALLY COMPLETE REACTION OF THE SODIUM SILICATE IN THE PRODUCTION OF THE PRECIPITATED ALUMINUM SILICATE BUT SUFFICIENTLY RESTRICTED TO AVOID RAISING THE PH OVER FOUR THROUGHOUT THE PRECIPITATION PROCESS.