Pressure-sensitive adhesive tape

Normally tacky and pressure-sensitive adhesive tape having good holding power, resistance to aging and comparatively low cost comprising a sheet backing bearing a composite adhesive stratum comprising a layer of rubbery, compliant polyurethane, and, bonded over the polyurethane layer so as to constitute the outermost surface, a layer of soft, normally tacky and pressure-sensitive adhesive which is immiscible with the polyurethane, the thickness of the polyurethane layer being at least about twice the thickness of the pressure-sensitive adhesive layer, the polyurethane having a 10-second shear-creep compliance of at least 5.times.10.sup.-6 cm.sup.2 /dyne, a 7-10 minute shear rate viscosity of at least 10.sup.6 Pa.s, a 7-10 minute delayed elastic compliance component greater than 50%, and an equilibrium elastic compliance greater than 90%, and the pressure-sensitive adhesive having a 10-second shear creep compliance component of at least 1.5.times.10.sup.-6 cm.sup.2 /dyne, a 7-10 minute shear rate viscosity of at least 3.times.10.sup.6 Pa.s, and a 7-10 minute delayed elastic compliance component greater than 50%, said tape exhibiting superior adhesive properties to those attainable with tape in which the backing is coated with either the polyurethane alone or the pressure-sensitive adhesive alone.