Abstract: A process and an apparatus for making a differential density cellulosic web comprising a first plurality of high-density micro-regions and a second plurality of low-density micro-regions are disclosed. The process comprises the steps of providing a fibrous web containing fluid-latent indigenous polymers and water; depositing the web on a fluid-permeable molding fabric; applying ultrasonic energy to the web, thereby contributing to softening of the fluid-latent indigenous polymers in at least selected portions of the web; impressing the molding fabric into the web, thereby densifying the selected portions of the web and causing the fluid-latent indigenous polymers to flow and interconnect the fibers which are mutually juxtaposed in the selected portions; and immobilizing the fluid-latent indigenous polymers, thereby creating bonds thereof between the fibers which are interconnected in the selected portions.

Abstract: An apparatus of parallel radiation for curing a resin to produce a resinous framework of a papermaking belt is provided. The apparatus comprises a source of radiation and an elongate reflector having an outer surface, an inner surface, a longitudinal axis, and two ends spaced apart along the longitudinal axis. The inner surface is comprised of a plurality of reflective facets oriented parallel to the longitudinal axis. In its cross-section, the reflector has a concave shape having a cross-sectional axis perpendicular the longitudinal axis. The reflective facets have a common focal point in the cross-section. The reflective facets direct radiation substantially parallel to the cross-sectional axis. Preferably, the plurality of reflective facets form the reflector's inner surface having a parabolic or circular macro-scale shape in the cross-section.