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Cloudy and easily marred powder coated finish

Hello, my name is Ed and I have a problem with some lobby furniture that was purchased for our medical facility approx.2 years ago. It was claimed to have a gloss silver powder coat finish. However, it is easily marred and the areas that are exposed and cleaned regularly have turned very dark. My question is how long should a finish like that last in that environment and is there any thing that should not be used to clean it. The coating itself is intact it has not chipped or peeled.

Edward Parker
buyer - Bakersfield, California, USA
April 22, 2008

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April 24, 2008

Hi Ed,

Sounds as though you have misunderstood what is meant by "a gloss silver powder coat". I think a little explanation what silver means. All silver powder coating materials are based upon aluminium flake. There are two types of flake, leafing that produces those bright and chrome effects and non-leafing for use in general purpose powders. The silver powder can be based on either one or a combination of both. Your finish sounds like a non-leafing aluminium has been used to formulate the "gloss" effect (aluminium resides inside the applied powder film). These are OK up to a point, but will not stand up to attack by acid/alkali based materials and those containing abrasives (cleaning products). The aluminium flake will start to darken (UV light) very quickly unless the applied silver powder is over-coated with a transparent polyester powder (look at some alloy silver coated wheels). The company who sold them to you may have thought the lobby furniture was just for show and you would dust them occasionally with a feather duster.

Terry Hickling
Birmingham, United Kingdom