  We experimentally investigate the bursting dynamics of confined liquid film
suspended in air and find a viscous dynamics distinctly different from the
non-confined counterpart, due to lack of circular symmetry in the shape of
expanding hole: the novel confined-viscous bursting proceeds at a constant
speed and a rim formed at the bursting tip does not grow. We find a
confined-viscous to confined-inertial crossover, as well as a
nonconfined-inertial to confined-inertial crossover, at which bursting speed
does not change although the circular symmetry in the hole shape breaks
dynamically.
