Iron oxide pigments

Claim 2

IN THE PROCESS FOR MAKING RED IRON OXIDE PIGMENTS SUBSTANTIALLY FREE OF COMBINED WATER WITHOUT CALCINATION WHICH INCLUDES A FIRST STEP OF REACTING METALLIC IRON AND ACID IN THE PRESENCE OF AN ALKALI MATEL SALT AND GASEOUS OXYGEN IN AQUEOUS MEDIUM, THEREBY FORMING RED IRON OXIDE IN SITU, THE NOVEL STEPS OF MATURING THE NEWLY FORMED RED IRON OXIDE BY ADDING TO THE MEDIUM CONTAINING IT A STRONGER OXIDIZING AGENT THAN OXYGEN, WHICH IS OF THE TYPE OF H2O2 AND THE HYPOCHLORITES, NEUTRALIZING THE MEDIUM TO A PH OF ABOUT 5.5 TO 6, AND HEATING THE MEDIUM TO ABOUT 50 TO 80* C. WITH THE CONTINUED INTRODUCTION OF GASEOUS OXYGEN FOR ABOUT 8 TO 48 HOURS.

Claim 3

IN THE PROCESS FOR MAKING RED IRON OXIDE PIGMENTS SUBSTANTIALLY FREE OF COMBINED WATER WITHOUT CALCINATION WHICH INCLUDES A FIRST STEP OF INSUFFLATING AN AQUEOUS SOLUTION OF AN IRON SALT OF A STRONG MINERAL ACID CONTAINING AN ALKALI METAL SALT AND METALLIC IRON WITH GASEOUS OXYGEN, ADDING A FERROUS SALT WHILE CONTINUING THE INSUFFLATION WITH GASEOUS OXYGEN UNTIL THE PIGMENT HAS THE DESIRED SHADE, AND ISOLATING AND WASHING THE PIGMENT, THE NOVEL MATURING STEPS WHICH COMPRISES ADDING A STRONGER OXIDIZING AGENT THAN OXYGEN, WHICH IS OF THE TYPE OF H2O2 AND THE HYPOCHLORITES, TO THE AQUEOUS DUCTION OF GASEOUS OXYGEN AND THE HEATING UNTIL THE DEMEDIUM, NEUTRALIZING THE MEDIUM TO ABOUT PH 5.5 TO 6 AND RASING THE TEMPERATURE OF THE MEDIUM TO ABOUT 50 TO 80* C. FOR ABOUT 8 HOURS.

Claim 4

IN THE PROCESS FOR MAKING RED IRON OXIDE PIGMENTS SUBSTANTIALLY FREE OF COMBINED WATER WITHOUT CALCINATION WHICH INCLUDES A FIRST STEP OF INSUFFLATING AN AQUEOUS SOLUTION OF AN IRON SALT OF A STRONG MINERAL ACID CONTAINING AN ALKALI METAL SALT AND METALLIC IRON WITH GASEOUS OXYGEN, ADDING A FERROUS SALT WHILE CONTINUING THE INSUFFLATION WITH GASEOUS OXYGEN UNTIL THE PIGMENT HAS THE DESIRED SHADE, AND ISOLATING AND WASHING THE PIGMENT, THE NOVEL MATURING STEPS WHICH COMPRISES ADDING A STRONGER OXIDIZING AGENT THAN OXYGEN, WHICH IS OF THE TYPE OF H2O2 AND THE HYPOCHLORITES, TO THE AQUEOUS DUCTION OF GASEOUS OXYGEN AND THE HEATING UNTIL THE DEMEDIUM, NEUTRALIZING THE MEDIUM TO ABOUT PH 5.5 TO 6 AND RASING THE TEMPERATURE OF THE MEDIUM TO ABOUT 50 TO 80* C. FOR ABOUT 8 HOURS.

Claim 5

IN THE PROCESS FOR MAKING RED IRON OXIDE PIGMENTS SUBSTANTIALLY FREE OF COMBINED WATER WITHOUT CALCINATION WHICH INCLUDES A FIRST STEP OF PREPARING RED IRON OXIDE PIGMENT SEEDS FROM AN AQUEOUS MEDIUM CONTAINING FERROUS SULFATE, INTRODUCING A FERROUS SALT TO THE AQUEOUS MEDIUM CONTAINING THE SEEDS AND CONTAINUING THE INTROSIRED SHADE AND QUALITY OF PIGMENT IS PRODUCED, THE NOVEL STEPS OF ADDING A STRONGER OXIDIZING AGENT THAN OXYGEN, WHICH IS OF THE TYPE OF H2O2 AND THE HYPOCHLORITES TO THE MEDIUM CONTAINING THE SEEDS, NEUTRALIZING THE MEDIUM TO A PH OF ABOUT 5.5 TO 6 AND MATURING THE SEEDS THUS PRODUCED BY HEATING THE MEDIUM CONTAINING THE SEEDS TO ABOUT 50 TO 80* C. WITH CONTINUED INTRODUCTION OF GASEOUS OXYGEN.

Claim 6

IN THE PROCESS FOR MAKING RED IRON OXIDE PIGMENTS SUBSTANTIALLY FREE OF COMBINED WATER WITHOUT CALCINATION WHICH INCLUDES A FIRST STEP OF PREPARING RED IRON OXIDE PIGMENT SEEDS FROM AN AQUEOUS MEDIUM CONTAINING FERROUS SULFATE, INTRODUCING A FERROUS SALT TO THE AQUEOUS MEDIUM CONTAINING THE SEEDS AND CONTAINUING THE INTROSIRED SHADE AND QUALITY OF PIGMENT IS PRODUCED, THE NOVEL STEPS OF ADDING A STRONGER OXIDIZING AGENT THAN OXYGEN, WHICH IS OF THE TYPE OF H2O2 AND THE HYPOCHLORITES TO THE MEDIUM CONTAINING THE SEEDS, NEUTRALIZING THE MEDIUM TO A PH OF ABOUT 5.5 TO 6 AND MATURING THE SEEDS THUS PRODUCED BY HEATING THE MEDIUM CONTAINING THE SEEDS TO ABOUT 50 TO 80* C. WITH CONTINUED INTRODUCTION OF GASEOUS OXYGEN.