title: Waterproof active paper via laser surface micropatterning of magnetic nanoparticles.
abstract: Paper is one of the oldest and most abundant materials known to man. Recently, there has been a considerable interest in creating paper devices by combining paper with other functional materials. In this letter, we demonstrate a simple fabrication technique to create water-resistant ferro-patterns on wax paper using CO(2) laser ablation. A resolution of about 100 μm is achieved which is mostly limited by the cellulose fiber size (~50 μm) in the wax paper and can be improved by using a smaller cellulose matrix. Laser ablation results in modification of surface morphology and chemistry, leading to a change in surface energy. We also present a 2D model for ferrofluid deposition relating the size of the pattern to the amount of ferroparticles deposited on the surface. Finally, a paper gripper is presented to demonstrate advantages of our technique, which allows microscale patterning and machining in a single step.
authors.affiliation: School of Mechanical Engineering, Purdue University, West Lafayette, Indiana, USA.
authors.forename: G
authors.initials: G
authors.lastname: Chitnis
authors.forename: B
authors.initials: B
authors.lastname: Ziaie
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry; D007501:Iron / Q000737:chemistry; D007834:Lasers; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D010209:Paper; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D058185:Magnetite Nanoparticles; D014867:Water; D002245:Carbon Dioxide; D002482:Cellulose; D007501:Iron