An aqueous coating composition comprising a crosslinkable
water-dispersible polyurethane oligomer wherein said composition when
drying to form a coating has an open time of at least 20 minutes, a
wet-edge time of at least 10 minutes, a tack free time of <20 hours
and an equilibrium viscosity of <5,000 Pas at a solids content when
drying in the range of from 20 to 55 wt % using a shear rate in the range
of from 9.+-.0.5 to 90.+-.5 s.sup.-1 and at 23+2.degree. C.