Large-area polymer patterns can now be easily obtained using microfluidic lithography, under conditions that overcome the slow pattern formation inherent to this technique. The strong temperature dependence of the viscosity of the polymers employed in microfluidic lithography is exploited to increase the filling rate of the elastomeric microchannels. The throughput of high-temperature lithography in capillaries by polyurethane can be increased by up to a factor of 60 with respect to the room-temperature process. In addition, the method can be applied to any kind of substrate and a variety of liquids.