Dissolve an accurately weighed quantity of Propylparaben in Purified Water with heating to about 50
and stirring. Cool, and dilute quantitatively, and stepwise if necessary, with Purified Water to obtain 90 mL of solution containing 20 mg of Propylparaben. Heat to about 50
, and add the Methylparaben, with stirring, to dissolve. Cool, stir with a blender, slowly sift the Xanthan Gum into the vortex, and continue to blend for 2 minutes after the Xanthan Gum has been added. Add 10 mL of Purified Water, and blend for 5 minutes. Allow to stand for 1 hour for excess foam to subside, and remove most of the remaining foam by passing the solution through a strainer. Add Purified Water, if necessary, to make the final volume 100 mL, and stir.
[NOTEDepending on the volume needed and the equipment available, adjust the formula proportionately.
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