TECHNOLOGY FOCUS - POLYMERS - Preferred System: The material having a finite yield stress or a high viscosity maintains mechanical dimensions of a structure deposited on a substrate, where the structure deposited on the substrate is comprised of the first ink, and is embedded at least in part within the one of the second ink or the sacrificial material. The mechanical dimensions of the structure are maintained in the presence of at least one force selected from surface tension forces, drying forces and wetting forces. The material having a finite yield stress or a high viscosity forms within 1000 seconds after the first ink or the sacrificial material comes into contact with the second ink. Preferred Components: The first ink comprises solid particles (preferably at least one material selected from metal, a ceramic, a polymer and a semiconductor). The solid particle comprises a volume fraction in excess of 20% of the first ink, and has a net electrostatic charge. The material having a finite yield stress is formed by gelation, preferably the gelation occurs via the neutralization of electrostatic charge on the solid particles. The material having a finite yield stress or a high viscosity is formed by chemical bonding of materials in the first ink and the one of the second ink or sacrificial material. The first ink comprises a monomer and the one of the second ink or sacrificial material comprises a catalyst or a cross-linking agent, and optionally a second monomer, and the material having a finite yield stress or a high viscosity is formed by a polymerization reaction. EXAMPLE - A first ink comprising diethylene glycol butyl ether as organic solvent, functional particles of polytetrafluoroethylene (PTFE), and trimethylpropane triacrylate (TMPTA) monomer were prepared. A sacrificial material comprising diethylene glycol butyl ether as organic solvent, and diethoxyacetophenone (DEAP) photopolymerization initiator were prepared. The two fluid streams were combined in the coextruder device to produce a printed bead comprising the first ink embedded at least partially within the second ink or sacrificial material, and this bead was subjected to UV exposure to polymerize the interface of the two inks. The resulting structure comprised of the first ink was observed to maintain dimensions of 50 mu m in height and 50 mu m in width, and did not experience slumping.