Phosphoric acid Electronic Grade can be obtained by chemical reaction of elemental phosphorus or phosphorus oxide, or by purification of finished phosphoric acid. The key to preparation is to control and achieve the required content and granularity of alkali metal and heavy metal impurity ions. Specifications: Items Units E1(LCD grade) E2(IC grade) H3PO4 % 85-87 85-87 H3PO3 % ≤0.005 ≤0.001 NO3 mg/kg ≤5 ≤0.5 SO4 mg/kg ≤10 ≤5 Cl mg/kg ≤1 ≤0.5 Al µg/kg  …