Spectrum Chemical manufactures and distributes fine chemicals with quality you can count on including those with CAS number 877-24-7, Whether you call it Potassium Biphthalate, Potassium Acid Phthalate , Phthalic Acid - Monopotassium Salt or Potassium Biphthalate you can be assured the Potassium Biphthalate products offered by Spectrum, meet or exceed the grade requirements or specifications for each individual product.