  We further analyse,at next-to-leading log(s) level,the form of
k-factorization and the definition of impact factors previously proposed by one
of us,and we generalize them to the case of hard colourless probes. We then
calculate the finite one-loop corrections to quark and gluon impact factors and
we find them universal,and given by the same K factor which occurs in the soft
timelike splitting functions.
