  Most of young and middle-aged supernova remnants (SNRs) exhibit an ionizing
plasma (IP), an ionizing process following a shock heated SNR gas. On the other
hand, significant fractions of SNRs exhibit a recombining plasma (RP). The
origin and the mechanisms of the RP, however, are not yet well understood. This
paper proposes a new model that the RP is followed after the IP process taken
at the first epoch of the SNR evolution. Using the high quality and wide band
(0.6-10 keV) spectrum of IC 443, we nicely fitted with a model of two RP
(two-RP model) plus a power law (PL) with an Fe I Kalpha line component. The
ionization temperature in one RP monotonously increases from Ne-Ca, while that
in the other RP shows a drastic increase from Cr-Ni. Origin and mechanism of
the two-RP and PL with an Fe I Kalpha line components are possibly due to a
different evolution of two plasmas and ionization by the low-energy cosmic ray.
