Phenolic Resin Dual-Use Stamps for Capillary Stamping and Decal Transfer Printing

Abstract

We report an optimized two-step thermopolymerization process carried out in contact with micropatterned molds that yields porous phenolic resin dual-use stamps with topographically micropatterned contact surfaces. With these stamps, two different parallel additive substrate manufacturing methods can be executed: capillary stamping and decal transfer microlithography. Under moderate contact pressures, the porous phenolic resin stamps are used for nondestructive ink transfer to substrates by capillary stamping. Continuous ink supply through the pore systems to the contact surfaces of the porous phenolic resin stamps enables multiple successive stamp−substrate contacts for lithographic ink deposition under ambient conditions. No deterioration of the quality of the deposited pattern occurs, and no interruptions for ink replenishment are required. Under a high contact pressure, porous phenolic resin stamps are used for decal transfer printing. In this way, the tips of the stamps' contact elements are lithographically transferred to counterpart substrates. The granular nature of the phenolic resin facilitates the rupture of the contact elements upon stamp retraction. The deposited phenolic resin micropatterns characterized by abundance of exposed hydroxyl groups are used as generic anchoring sites for further application-specific functionalizations. As an example, we deposited phenolic resin micropatterns on quartz crystal microbalance resonators and further functionalized them with polyethylenimine for preconcentration sensing of humidity and gaseous formic acid. We envision that also preconcentration coatings for other sensing methods, such as attenuated total reflection infrared spectroscopy and surface plasmon resonance spectroscopy, are accessible by this functionalization algorithm.

Solvent-Free High-Temperature Capillary Stamping of Stimuli-Responsive Polymers: Wettability Management by Orthogonal Substrate Functionalization

“…Stamps exhibiting continuous pore systems − have been used for additive substrate patterning in automatized configurations and even under the extreme conditions of solvothermal syntheses . However, percolative transport of viscous mixtures containing polymers and additional components impeding flow, such as CNTs, through porous stamps might be too slow for efficient stamping procedures.…”

Reactive Additive Capillary Stamping with Double Network Hydrogel-Derived Aerogel Stamps under Solvothermal Conditions

“…The direct deposition of patterns of solvothermal reaction products may be achieved by the coupling of solvothermal syntheses with in situ additive substrate patterning. It was shown that porous stamps − are particularly suitable for parallel additive substrate patterning even if diluted precursor solutions are used as inks because the pore systems of the stamps act as ink reservoirs. Evaporation of the volatile ink components (typically the solvents) drags more and more of the nonvolatile ink components, such as precursors of solvothermal reaction products, into the liquid ink bridges formed between the contact elements of the stamp and the substrate to be patterned.…”

“…The enrichment of the nonvolatile ink components in the liquid bridges is a crucial aspect of additive pattern formation with porous stamps . However, the porous stamps so far available are not compatible with solvothermal processes; polymeric stamps ,, are too deformable, whereas silica , and phenolic resin stamps are too brittle. In general, reactive additive lithography has, so far, predominantly been conducted with solid stamps under ambient pressure and temperature …”