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This study concerns the application of parylene conformal coating technology to the preservation and/or protection of archival materials and museum artifacts. Topics discussed are the properties of the polymer, the process of deposition, stress tests conducted on parylenetreated paper, encapsulation of entire books, artifact analog studies, as well as the restoration and subsequent treatment of an antique microscope with parylene.

Arrays of 80‐μm‐high mesas and 250‐μm‐deep wells were formed in silicon using conventional etching techniques. Oxide and metal patterns were photodefined over the sloping walls of these structures using the inorganic resist Ag2Se/Ge0.15Se0.85. A 2000‐A‐thick conformal coating of the chalcogenide Ge0.15Se0.85 was sputter deposited onto the etched silicon wafers. Sensitized in a Ag(CN)−2 containing aqueous bath, the resist was exposed through a mask on a contact printer. Patterns were delineated using established wet chemical developing procedures and then transferred to underlying oxide or metal to form implant windows or metal conductors, respectively. Image defocusing over the depth of the etched silicon features produced some linewidth changes down the sloping walls, but useful conductors were fabricated.

Encapsulation of pharmaceutical powders within thin functional polymer films is a powerful and versatile method to modify drug release properties. Conformal coating over the complete surface of the particle via chemical vapor deposition techniques is a challenging task due to the compromised gas&ndash, solid contact. In this study, an initiated chemical vapor deposition reactor was adapted with speakers and vibration of particles was achieved by playing AC/DC&rsquo, s song &ldquo, Thunderstruck&rdquo, to overcome the above-mentioned problem. To show the possibilities of this method, two types of powder of very different particle sizes were chosen, magnesium citrate (3&ndash, 10 &micro, m, cohesive powder) and aspirin (100&ndash, 500 &micro, m, good flowability), and coated with poly-ethylene-glycol-di-methacrylate. The release curve of coated magnesium citrate powder was retarded compared to uncoated powder. However, neither changing the thickness coating nor vibrating the powder during the deposition had influence on the release parameters, indicating, that cohesive powders cannot be coated conformally. The release of coated aspirin was as well retarded as compared to uncoated aspirin, especially in the case of the powder that vibrated during deposition. We attribute the enhancement of the retarded release to the formation of a conformal coating on the aspirin powder.