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E-coating for silver jewelry
Q. What compounds should be used for e-coating for silver jewelry? Our items are coated with silver and do not tarnish for about 12 months. Is this considered to be e-coating? Or should the coating be an organic lacquer for our silver jewelry items to be considered as e-coated in the U.S.?Victor Sazlo
INDUSTRIALIST - Milano, Italy
A. Silver plated items are generally coated with clear polyurethane electrophoretic lacquer which gives it very good tarnish resistance. Theoretically silver plating does qualify to be called e-coating but in actual practice e-coat refers to electrophoretic coating. Try www.electrocoat.org for complete information of E-coating.
Q. E-COATING over sterling silver: is there a standard? Or when you are requested to E-coat silver jewelry you can use any method you want, like electro coating with 100% silver as a protection layer?Yossi Rozenfeler
jewelry manufacturer - Rosh Haayin, Israel
A. First a clarification. Theoretically, E-coat could be any electrolytic coating process. However, in general use, at least in this part of the world, E-coat is usually used for the Electrophoretic coating. And you do go on to mention Silver plating. Electrophoretic clear lacquer coating does give excellent tarnish protection to Silver. Electrophoretic clear lacquer coatings have their standard specifications. I hope this helps.
A. Hi Victor; hi Yossi. I am sensing that you are confused what e-coating is about. As correct and informative as Gurvin's answers are, you may still be confused. Yes, sure, Gurvin covers all the bases when he says that e-coat could theoretically mean any electrolytic coating process. But to people in the business like you, Gurvin and I, "e-coating" or "electrocoating" always has the more specific meaning of electrolytically applying an organic topcoat with properties fairly similar to paint.
People might well call silver plating "electroplating", but they would never call it "electrocoating". Rather, people like you might do silver electroplating of jewelry and, upon realizing that it tarnishes, might look for a way of deterring the tarnishing. One of the ways of deterring tarnishing would be to apply a clear coat to seal the silver surface away from the air; and one of the excellent ways of applying a very thin clearcoat with excellent properties is electrocoating. In electrocoating the object is immersed in a tank with charged polymer ions floating in the solution. Electricity is applied to the part, and this oxidizes or reduces those ions to convert them to a solid organic coating on the parts. Good luck.
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Q. E-coating oxidized silver? I am very interested in getting an answer to the problem because it is causing me a lot of trouble with my clients.
The competition says that they can e-coat silver that has been oxidized with potassium sulphate with no problem -- but somehow we cannot do it.
Can you help me address this issue?
plating shop employee - Bolivia
June 29, 2010
Q. I have some E-coat problems. So I would like to know how to check E-coat. Is complete coverage enough ?Wassana S.
Operations Manager - Illinois
RFQ: I am looking for a small e-coat set up for a costume jewelry model shop.
The e-coat is to cover silver plated items to prevent tarnishing. Maintaining the color integrity of the silver plate is critical to the end customer.
Is there a way to do e-coat on a very small scale?
- Yonkers, New York
^- Sorry, this RFQ is outdated
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A. Yes, it can most certainly be done on a very small scale. in fact, a small bath of 20 to 40 liters will be more than sufficient. Being in the US you can get a small laboratory size UF which can be integrated for lacquer recovery.
You will get a link from our company web site. For more specific guidance you can write to us.
Best of luck.
(2007) -- this entry appended to this thread by editor in lieu of spawning a duplicative thread
Q. I am a chemist of electroplating company of fashion jewelry. We plate Gold and Rhodium fashion jewelries. Our client specification for our plated jewelry must be 6 month warranty without tarnishing or if possible small percentage of returns. Our problem is, our plated items tarnished within only 1 month . Please can you give us any way to prevent tarnishing easily or please give us any supplier to supply us anti-tarnish E-coat just to protect our items from tarnishing within 6 months warranty.Your support will be great help in our company.Constantino Cusipag
Chemist - Quezon City, Philippines
A. Electrophoretic clear lacquer is used extensively for exactly this purpose.
You can go ahead with it and expect complete resolution to this particular problem. Please ensure that the quality of electrocoating lacquer is up to the mark and it does not add to your problems.
Best of luck.
September 17, 2012
Q. I use silver, copper and brass for jewelry making. Does e-coating have better adhesion on any one of them?Sally Richards
- Ludington, Michigan usa
February 4, 2009
Q. RESPECTED SIR,
WE WOULD LIKE TO KNOW HOW E-COATING CAN BE DONE ON SILVER AND GOLD JEWELLERY.
WHAT ARE THE BENEFITS OF THE SAME. ?
- JAIPUR, RAJASTHAN, INDIA
March 3, 2009
A. The benefit is that the silver will not tarnish and flash gold (is it flash?) will not rub off.
E-coat is the best top coat for this application.
Find a supplier, there are many.
chemical process supplier
March 22, 2009
A. Do lacquer over base coat (any colour you want). if you are doing business in bulk you could install an E Coat line for lacquer.
- DELHI, INDIA
February 27, 2017 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread
Q. Hello, we are currently developing a new jewellery production in brass with silver plating and we don't know if 4 microns of silver is better than 2 microns with e-coating.
Also we are trying to find out what is the best option for under coating apart from nickel as we want our jewellery to be nickel free.
Our ideal coating should last about two years also for rings.
Any suggestion? We read that bronze is a good undercoating to keep silver not tarnish with brass, is it correct?
Thank you very much
product designer - Toscana, Italy
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