4-Hydroxybenzoic Acid CAS 99-96-7 Purity ≥99.5% Factory High Quality

4-Hydroxybenzoic Acid, also known as p-Hydroxybenzoic acid (PHBA) CAS 99-96-7, is a monohydroxybenzoic acid, a phenolic derivative of benzoic acid. It is a white crystalline solid that is slightly soluble in water and chloroform but more soluble in polar organic solvents such as alcohols and acetone. 4-Hydroxybenzoic Acid is primarily known as the basis for the preparation of its esters, known as parabens, which are used as preservatives in cosmetics and some ophthalmic solutions. It is isomeric with 2-hydroxybenzoic acid, known as salicylic acid, a precursor to aspirin, and with 3-Hydroxybenzoic acid. 4-Hydroxybenzoic Acid is used as an intermediate for dyes, antiseptics and active pharmaceutical ingredients. It is also used as a food preservative, corrosion inhibitor, anti-oxidant and an emulsifier. It reacts with 6-hydroxynaphthalene-2-carboxylic acid to prepare aromatic polyester called Vectran fiber. It acts as a precursor to prepare p-hydroxyphenylbenzoate, p-acetoxybenzoyl chloride and 4,4'-Dihydroxybenzophenone. Further, it is used in paint additives, coating additives, processing aids, electrical and electronic products. In addition to this, it acts as a preservative in cosmetics and some ophthalmic solutions. 4-Hydroxybenzoic Acid is of significant commercial importance.