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GEOMET® V.S. DACROTIZED®
WHAT IS GEOMET®? Environmental awareness has in recent years encompassed the globe, and increasingly stringent laws are being enacted to regulate toxic substances. Among others, the use of hexavalent chromium a substance heretofore widely used as an effective coating for the prevention of rust is likely to be regulated and phased out under the new environmental regulations, chiefly those being adopted in the U.S. and Europe. Responding to this trend, Allied Signal, in collaboration with Metal Coatings International Inc. (U.S.) and DACRAL  S.A. (France), has developed GEOMET® based on DACROTIZED®, the rust- preventive coating technology that has been perfected through 30 years of real-world application. GEOMET® coating film has a silver-metallic look. Layers of metal flakes are connected with one another through the use of a special inorganic binder. Because the film is extremely thin-only about 8μm it won't negatively affect the optimal fit between bolts and nuts. WHAT IS DACROTIZED®?
The solution (DACRODIP) used for the DACROTIZED® coating is a water-based dispersant containing metallic zinc flakes, chromic anhydride, glycol, etc. Soaking the target substrate in DACRODIP and heating the solution to approximately 300°C in an oven will reduce the  by-production of hexavalent chromium by organic substances such as glycol. The resulting water-insoluble amorphous nCrO3
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