Wɔ afe 1937 mu no, wɔyɛɛ P-phenylenediamine a ɛko tia onyin a ɛyɛ pɛpɛɛpɛ sen biara, a wɔfrɛ no "4000 Series Anti-Aging Agent", a 4010, 4010NA, 4020, 4030. ka ho.
Antioxidant 4010NA: Wɔsan frɛ no antioxidant IPPD, N-isopropyl-n, phenyl-p-phenylenediamine.
Antioxidant 4010: Wɔsan frɛ no antioxidant CPPD, N-cyclohexyl-n’-phenyl-p-phenylenediamine.
Antioxidant 4020: Wɔsan frɛ no antioxidant 6ppd, n-(1,3-dimethyl)butyl-n'-phenyl-p-phenylenediamine.
Antioxidant 4030: Wɔsan frɛ no antioxidant 7ppd, N, N'-BIS(1,4-DIMETHYLPENTYL)-P-phenylenediamine.