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Electroplating Plastics

2004

Dear Expert(s),

I am an mfg university student, I've read some books on electroplating on metal products, here, I have the interest on how to decorate a plastic part (such as bathroom water taps) to have a shiny metallic appearance, could you kindly describe it in details, as this really arouse my interest^^ Thank you.

Regards,

Joseph Choi
student - Hong Kong

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Joseph, you are studying manufacturing in the university, and you've read books on electroplating. Surely you realize then that it is not possible to describe something of this complexity in detail in the space commensurate with an internet forum

So, skipping the details, the plastic is etched to give it good "tooth" for adhesion. Then it's dipped into a solution of palladium chloride to give some "seed points". Then it's put into an electroless nickel plating tank where the palladium serves as a catalyst to start the nickel toward plating out of solution. The electroless nickel solution is autocatalytic, so the electroless nickel keeps building until it is thick enough. Then the part can be plated as if it were metal. This is a very "broad brush" description and you would need to buy the proprietary process from a chemical supplier in order to actually do it.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

Dear Ted,

Thank you for your advice on my question. You are right, I should read books on that, but before I ask you question, I've actually done that. I think I've made my question unclear before, sorry for that. My actual question is if I do not create tooths on the plastic surface, could I still do the electroless plating? And, I've read some books on electroless plating, most of them don't give me any suggestion on smooth surface electroless plating. One more question I'd like to ask is that, after electroless plating on plastic surface as you taught me before, how can I ensure its smoothness of the surface? Also, if I plate on PVC or PE plastics, how could I enhance the adhesion of the plating material to the plastics surface? Thank you for your valuable teaching and your valuable time.

Regards,

Joseph Choi
- Hong Kong
2004

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Sorry, Joseph, I don't have an answer to how you can get strong adhesion on plastic without etching into it for tooth.

And actually, I don't have the experience to know if the palladium route to electroless plating a smooth substrate will work; I don't personally know the exact mechanism of the palladium seeding well enough to know whether it can function properly with no etched depressions in the substrate.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004