Citric Acid → Magnesium Phosphate

関与物質

反応条件

反応手順

1280 g of de-ionized water was introduced into a 1 gallon vessel fitted with a Kady® Lab Mill and stirred at a motor speed of 15 Hz. 17.2 g of trisodium phosphate decahydrate and 2 g of citric acid were then added to the vessel. The temperature of the vessel was increased to 98° C. and 133 g of 3.5% aqueous solution of magnesium chloride was titrated into the vessel. 10 minutes after completion of the magnesium chloride addition, a sample was taken from the vessel and pH of the sample was measured to be 7.7. The motor speed of Kady® Mill was then increased to 45 Hz, and 160 g of Coarse Polymer Powder was introduced into the vessel. 30 minutes after introduction of the Coarse Polymer Powder, the vessel was rapidly cooled to 70° C. and the motor speed of the Kady® Mill was then reduced to 20 Hz while cooling continued until the temperature reached 25° C. The resulting slurry was filtered through a 45 μm filter, and the particle size was measured by Coulter Counter® Z2. Because of limitations associated with the Coulter Counter® Z2, two measurements were made. The first measurement, which is represented by FIG. 1, was for particles between 2.913 microns and 9.579 microns. The second measurement was for particles between 9.574 microns and 27.08 microns. The raw data was imported to an Excel spreadsheet, and volume average particle size, Pv, and number average particle size, Pn, between 2.913 microns to 15.08 s microns was calculated by the spreadsheet. Volume average particle size, Pv, was 5.7 μm, number average particle size, and Pv/Pn was 1.33. The resulting fine particle slurry was then washed with hydrochloric acid solution, and followed by additional cycles of de-ionized water washing and filtration, and finally was dried to become a Fine Powder. 0.5% of Aerosil R-972® and 0.5% of Aerosil® RX50 fumed silica (Supplied by Degussa, Parsippany, N.J.) based on the Fine Powder was added to the Fine Powder in a Henschel Mixer™. A color toner was obtained.

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