Electron-beam curing of coatings

The electron beam curing of coatings has for some time attracted a great deal of attention since It Is claimed that coatings can be fully cured In a fraction of a — second. The coatings are primarily based on the cross-linking of acrylic or epoxy resins In a polyurethane or polyester base (l.e., modified paints). 

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... 

A facile method by which organic thin films may be readily coated upon substrates employs the electron beam curing of materials such as of monomeric and/or oligomeric acrylates and methacrylates. The perfluorinated acrylates 2-(N-butylperfluorooctanesulfonamido)ethyl acrylate (BFOSA), 2-(N-ethylperfluorooctanesulfonamido)ethyl acrylate (EFOSA), and perfluoropolyether diacrylate (PFEDA) were obtained from the 3M corporation, St. Paul, Minnesota 1,6-Hexanediol diacrylatc (HDODA) was obtained from Interez, Inc., Louisville, Kentucky. 

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

Both u.v. radiation and electron beam curing are best suited to flat or nearly flat objects, because the beams are directional and shielding must be avoided. Electron beam curing also requires the coating to be in an oxygen-free gaseous atmosphere. Both techniques cure in a fraction of a second and are suitable for fast, high-volume production lines. 

Powers, H. R., "Electron Beam Curing for Coil Coatings, A Study of The Energy Requirements". Sherwin-Williams Company, 1975. 

Radiation-curable coatings (RC) should enjoy a dramatic growth as the full extent of their solvent-free, rapid, and ambient-curing properties is realized and materials and application systems are perfected. UV-curable coatings are currently the most important in this category however, electron beam (EB) curable coatings should show excellent growth to 1987 and beyond. 

Electron beam induced reactions continue to grow in importance. This paper provides an introductory treatment of the equipment and materials options, including a mechanistic and kinetic view of the pertinent chemistry. Specific coverage inciudes several applications in polymer science, especially in curing of coatings. 

Thin films were spin-coated onto virgin, optically flat NaCl disks or flat, polished Si wafers and electron beam cured at, 5-lOMrad under Nj. The oxygen content in the irradiation chamber was equipment used for electron beam curing was a CB 150 Electrocurtain Processor (Energy Sciences, Inc., Woburn, Mass.) that permits the exposure of. samples in the presence of air or an inert atmosphere like Nj. A scries of experiments were performed to determine the optimal ab-sorbed do.se for curing this was determined to be about 10 Mrads. 

Kumar, V, Bhardwaj, YK, Goel, NK, Francis, S, Sarma, KSS, Dubey, KA, Chaudhari, CV, Sabharwal, S. 2008. Coating characteristics of electron beam cured bisphenol A diglycidyl ether diaciylate resin-co-aliphatic urethane acrylate resins. Surf Coat Technol 202 5202-5209. 

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