Boric acid, hydrogen borate, boracic acid, orthoboric acid and acidum boricum, is a weak acid of boron 1.Used in producing optical glass, acid-resisting glass ... 20FCL.-According to the customer's requirement ItemIndexFirst gradeSecond gradeBoric acid(%)≥99.5%≥96.5%Water insolubles(%)≤0.05%≤0.15 ... .01%≤0.05%Iron(Fe)(%)≤0.003%≤0.005% pharmaceutical grade boric acid