title: Optimizing photo-embossed gratings: a gradient library approach.
abstract: Methodologies for the rapid screening of coating systems were developed and applied to photopolymer lacquers for photoembossing applications. Continuous and discrete gradient libraries were prepared with a gradient in grating period along the short axis and along the long axis, a gradient in exposure energy, development temperature, film thickness, photoinitiator concentration, or monomer to polymer mass ratio. Discrete gradient libraries consisted of arrays of rectangular films made by pipetting a certain amount of sample onto a chemically patterned substrate consisting of hydrophilic patches surrounded by hydrophobic, fluorinated barriers. The shape and height of the photoembossed gratings were measured using an automated AFM. Optimum grating height was obtained for a 20-microm period at intermediate exposure energies, photoinitiator concentrations, or both. Height improves with development temperature (max 110 degrees C), monomer-to-polymer ratio (max 55 wt % monomer), and film thickness. Surface topography can also be optimized, depending on any specific application.
authors.affiliation: Laboratory of Macromolecular Chemistry and Nanoscience, Department of Chemical Engineering, Eindhoven University of Technology and Dutch Polymer Institute (DPI), PO Box 513, 5600 MB Eindhoven, The Netherlands.
authors.forename: Berend-Jan
authors.initials: BJ
authors.lastname: de Gans
authors.forename: Carlos
authors.initials: C
authors.lastname: Sanchez
authors.forename: Dimitri
authors.initials: D
authors.lastname: Kozodaev
authors.forename: Daan
authors.initials: D
authors.lastname: Wouters
authors.forename: Alexander
authors.initials: A
authors.lastname: Alexeev
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Escuti
authors.forename: Cees W M
authors.initials: CW
authors.lastname: Bastiaansen
authors.forename: Dirk J
authors.initials: DJ
authors.lastname: Broer
authors.forename: Ulrich S
authors.initials: US
authors.lastname: Schubert
mesh_terms: D002152:Calorimetry, Differential Scanning; D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D007202:Indicators and Reagents; D010777:Photochemistry; D011109:Polymethacrylic Acids / Q000737:chemistry*
chemical_list: D007202:Indicators and Reagents; D011109:Polymethacrylic Acids; C098156:polybenzylmethacrylate