Surface Modification of Titanium Dioxide for Nobel White Pigment With Condensed Phosphoric Acid Treatment

Synthesis of Novel Cosmetic White Pigment by Condensed Phosphoric Acid Treatment of Zinc Oxide

“…These condensed phosphates have different reactivity from non-condensed orthophosphates, and it is expected that new materials can be obtained by using these condensed phosphates. In a previous study, novel white pigments for cosmetics were prepared by a condensed phosphate treatment of titanium dioxide [14]. The results showed that condensed phosphates are suitable for mild phosphoric acid coatings.…”

“…The chemical composition, particle size distribution, photocatalytic activity, hue, and smoothness of the obtained samples were investigated for cosmetic applications. EXPERIMENTAL Sodium pyrophosphate, Na 4 P 2 O 7 , was synthesised by heating disodium hydrogen phosphate (Na 2 HPO 4 ) at 400 ºC for 5 h [14]. Sodium triphosphate (Na 5 P 3 O 10 ) was synthesised by heating a mixture of disodium hydrogen phosphate (Na 2 HPO 4 ) and sodium dihydrogen phosphate (NaH 2 PO 4 ) at a Na 2 HPO 4 /NaH 2 PO 4 ratio of 2/1 at 400 ºC for 5 h. Sodium polyphosphate, NaPO 3 , was synthesised by heating sodium dihydrogen phosphate, NaH 2 PO 4 at 700 ºC for 2 h, followed by rapid cooling.…”

“…Zinc oxide was added to 50 mL of the above condensed phosphate solution or condensed phosphoric acid at a P/Zn molar ratio of 1/2 in a glass tube. These mixtures were shaken in hot water (50 ºC) at a shaking rate of 100 times/min for 1 h [13,14]. The powder samples were decanted, washed with water, and dried at 50 ºC over 3 days.…”