 CR-39 is now a trade-marked product of PPG Industries.An alternative use includes a purified version that is used to measure neutron radiation, a type of ionizing radiation, in neutron dosimetry.Although CR-39 is a type of polycarbonate, it should not be confused with the general term polycarbonate, a tough homopolymer usually made from bisphenol A.

CR-39 is made by polymerization of diethyleneglycol bis allylcarbonate (ADC) in presence of diisopropyl peroxydicarbonate (IPP) initiator.