  We present a numerical study of the process of production of kink-antikink
pairs in the collision of particle-like states in the one-dimensional $\phi^4$
model. It is shown that there are 3 steps in the process, the first step is to
excite the oscillon intermediate state in the particle collision, the second
step is a resonance excitation of the oscillon by the incoming perturbations,
and finally, the soliton-antisoliton pair can be created from the resonantly
excited oscillon. It is shown that the process depends fractally on the
amplitude of the perturbations and the wave number of the perturbation. We also
present the effective collective coordinate model for this process.
