After inkjet printing
onto uncoated and unsized paper, the ink
is first imbibed into the interfiber pores and subsequently absorbed
by the cellulose fibers. The achievable print quality depends on the
rate of this pore-fiber transport. The latter is accompanied by mechanical
expansion of the fibers and the paper sheet. Therefore, we systematically
monitored the swelling dynamics of several paper types as a function
of ink composition by means of four different measurement techniques.
Using aqueous cosolvent solutions as model inks, we found an approximately
exponential relation of the time scales of pore-fiber transport with
the cosolvent concentration and an approximately linear relation with
its molecular weight. Addition of surfactants can substantially speed-up
pore-fiber transport.