The Cronak process is a conventional chromate conversion coating process developed in 1933 by The New Jersey Zinc Company. It involves immersing a zinc or zinc-plated article for 5 to 15 seconds in a chromate solution, typically prepared from sodium dichromate and sulfuric acid. The process was patented in the United States on March 24, 1936 with USPTO number 2,035,380.
External links
- https://web.archive.org/web/20141211093127/http://www.innovateus.net/science/what-zinc-chromate-used
References
Gregory Zhang, Xiaoge (1996). Corrosion and Electrochemistry of Zinc. Springer Verlag Gmbh. pp. 16, 17. ISBN 978-1-4757-9877-7. Retrieved 12 December 2014. 978-1-4757-9877-7 ↩
"New Protective Zinc Coating Introduced". The Iron Age. Vol. 137, no. 22. May 28, 1936. p. 94. Retrieved 8 Mar 2023 – via Internet Archive. https://archive.org/details/sim_chiltons-iron-age_1936-05-28_137_22 ↩
US patent 2035380, Ernest John Wilhelm, "Method of coating zinc or cadmium base metals", published 1936-03-24, issued 1936-03-24, assigned to The New Jersey Zinc Company https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US2035380 ↩