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Molded or formed plastic needs a good mirror finish

I am trying to find the best way to have a molded plastic have a mirrored area which is good enough to image not just reflect. I understand that electroplating could be a candidate and would like to discuss the options. Eventual quantities are to be in the thousands, but initial testing and evaluating will be necessary. This is a near term design requirement lasting about 4 months for a solution.
Are good well polished transfer plattens a solution to a premolded shape? in other words is it possible to have a shape and then imprint a secondary process to the intended area to get a good finish quality before the plating is applied?
thanks in advance.
Oskar

Oskar Kirsten
research engineer - San Diego, California, USA
November 17, 2008

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Hi, Oskar. The auto industry uses tons of chrome plated plastic, but chrome may be too absorptive for your purposes. Rhodium plating may be better. A likely alternative is vacuum metallizing with aluminum. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
November 18, 2008

If you are looking for true optical quality image, your chances of getting it from plastic are very limited due to its low rigidity and dimensional stability. I don't know anything about your project but just to give you a example think about two different parts in your car. The headlamps inner surfaces. They're made of plastic (indeed a thermoset resin metallized with aluminum) but they only need to project light, not to "image". On the other hand, the mirrors. They are made of floated and perfectly flat glass with its first surface coated with chrome. Certainly not as shinny as the lamps, the front grille or the trim but optically true.

Guillermo Marrufo
Monterrey, NL, Mexico
November 21, 2008