ELECTRON BEAM COATING

Coating materials may be based on short or medium-oil alkyds (e.g. primers for door and window frames) nitrocellulose or thermoplastic acrylics (e.g. lacquers for paper or furniture finishes) amino resin-alkyd coatings, with or without nitrocellulose inclusions, but with a strong acid catalyst to promote low temperature cure (furniture finishes) two-pack polyurethanes (furniture, flat boards) unsaturated polyester resins in styrene with free-radical cure initiated by peroxides (furniture) or unsaturated acrylic oligomers and monomers cured by u.v. radiation or electron beams (coatings for record sleeves paperback covers, knock-down furniture or flush interior doors). 

Photomechanical Responses of Azobenzene-Containing Materials. Ji et al. (2004) reported that a self-assembled monolayer (SAM) of azobenzene molecules on a silicon microcantilever created a photon-driven switch. Commercial silicon microcantilevers were electron-beam coated on one side with 3nm of primer layer (chromium), followed by 20 nm of gold. An azobenzene derivative with a decanthiol substituent on one ring was used to functionalize the gold surface. The thiol (-SH) end attached to the gold surface and the other azobenzene end disposed outward. 

Ultraviolet Electron Beam Curing Formulations for Printing Ink, Coating and Paints, 3 Vols., SiTA Technology, London, 1991. 

Miscellaneous. Electron beams can be used to decompose a gas such as silver chloride and simultaneously deposit silver metal. An older technique is the thermal decomposition of volatile and extremely toxic gases such as nickel carbonyl [13463-39-3] Ni(CO)4, to form dense deposits or dendritic coatings by modification of coating parameters. 

Curing of Coatings with Electron Beams, y-Ray, X-Ray, and Planar Cathodes... 

Advantages of the electron beam processor are its abiUty to penetrate thick and highly pigmented coatings. It is used to cross-link reactive unsaturated polymers, nonreactive thermoplastic polymers, iasulation, and wire-cable covetings (4,9,16) (see Insulation, electric-wire and cable COVERDIGS). 

Wood furniture (ir-, electron beam-, and uv-curable coatings)... 

Packaging, eg, paper, foil, and film (uv and electron-beam inks and coatings)... 

Overlay coatings onto gas-turbine blades and vanes of M—Cr—Al—Y type alloys by electron beam evaporation is estimated at 10 x 10 to coat 200,000 parts at an average cost of 50 per part. 

The pursuit of further miniaturization of electronic circuits has made submicrometer resolution Hthography a cmcial element in future computer engineering. LB films have long been considered potential candidates for resist appHcations, because conventional spin-coated photoresist materials have large pinhole densities and variations of thickness. In contrast, LB films are two-dimensional, layered, crystalline soHds that provide high control of film thickness and are impermeable to plasma down to a thickness of 40 nm (46). The electron beam polymerization of CO-tricosenoic acid monolayers has been mentioned. Another monomeric amphiphile used in an attempt to develop electron-beam-resist materials is a-octadecylacryUc acid (8). 

Donor and acceptor levels are the active centers in most phosphors, as in zinc sulfide [1314-98-3] ZnS, containing an activator such as Cu and various co-activators. Phosphors are coated onto the inside of fluorescent lamps to convert the intense ultraviolet and blue from the mercury emissions into lower energy light to provide a color balance closer to daylight as in Figure 11. Phosphors can also be stimulated directly by electricity as in the Destriau effect in electroluminescent panels and by an electron beam as in the cathodoluminescence used in television and cathode ray display tubes and in (usually blue) vacuum-fluorescence alphanumeric displays. 

An XPS spectrometer schematic is shown in Figure 7. The X-ray source is usually an Al- or Mg-coated anode struck by electrons from a high voltage (10—15 kV) Alka or Mgka radiation lines produced at energies of 1486.6 eV and 1256.6 eV, with line widths of about 1 eV. The X rays flood a large area (-I cm ). The beam s spot size can be improved to about lOO-jim diameter by focusing the electron beam... 

Sulfur chemistry [29] has also been used to crosslink rubber/resin PSAs, although the use of elemental sulfur itself yields tapes that can stain substrates. Other patents exemplify the use of typical rubber vulcanizing chemistry such as Tetrone A , dipentamethylenethiuramtetrasulfide, and Tuads , tetramethylthiu-ram disulfide [30], or zinc butyl xanthate [31] for this purpose. Early art [32] also claimed electron beam curing of both natural rubber and other adhesives that were solvent coated on tape backings. Later references to electron beam curing... 

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