Halox CW-22/221 Calcium borosilicate Halox Functional pigment >> Anti-corrosive Corrosion inhibitor Alkyd Resins Corrosion Inhibiting Pigments HALOX® CW-22/221 Borosilicate Medium Oil Alkyds Long Oil Alkyds Borosilicate. Used as a corrosion inhibitor for medium and long oil alkyds.