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Enthone Introduces AlphaSTAR® 420R PWB Creep and Flaking Corrosion Inhibitor


 WEST HAVEN, Connecticut, USA, January 6, 2011 - Enthone Inc., a business of Cookson Electronics, has introduced AlphaSTAR® 420R, the industry's only production-proven solution that prevents both creep and flaking corrosion seen in harsh PWB service environments. Used as a final post-treatment step in the patented AlphaSTAR  PWB immersion silver process, AlphaSTAR 420R is specially formulated to enhance corrosion resistance and deliver a tarnish-free surface. The process meets the most complex lead-free assembly, end use performance and application requirements as mandated by the world's leading OEMs, PWB assemblers and fabricators.

When used as part of the AlphaSTAR immersion silver process, AlphaSTAR 420R provides a solution to creep corrosion (a condition in which shorts are formed across copper component mounting pads or circuit traces by copper salt migration) and flaking corrosion (a peeling of the corrosion product beneath the PWB surface) that can occur when free copper is exposed to a harsh environment on PWB circuitry.
Unlike solvent-based systems, AlphaSTAR 420R is water soluble chemistry that enables ease of application, handling and rework. No additional, costly equipment is required. AlphaSTAR 420R readily penetrates micropores (where corrosion can propagate). If corrosion should form, AlphaSTAR 420R ensures that the corrosion is suppressed, thus reducing the risk of shorts from flaking conductive material.
AlphaSTAR 420R corrosion inhibitor retains exceptional solderability and conductivity when used as part of the AlphaSTAR process. Extensive OEM builds have reported no degradation of solderability or other assembly issues.
Further information on the AlphaSTAR process, including the technology update, "Frequently Asked Questions on Creep and Flaking Corrosion," may be obtained by visiting
About Enthone
Enthone Inc. is a business of Cookson Electronics The company is a global and leading supplier of high performance specialty chemicals and coatings. Enthone manufactures, markets and distributes its functional, decorative and electronic processes that are used in printed wiring board, semiconductor, photovoltaic, automotive, energy, aerospace, jewelry, and plumbing applications. For more information, please visit

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