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How to plate a conductive film inside of a plastic box

2006

Dear Sir,
One of my customers wants to plate a conductive film inside of s plastic box. Which process should we use to plate this box and There are hundreds of thousands of this box.
I got a picture of the box but I don't know where to send it.
Thank you very much for your interest

Tayyar BEK
- Istanbul, Turkey

Ed. note: email the picture to mooney@finishing.com, Tayyar.

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The process you need to do is POP (plating on plastic) which consists of 3 stage:

1. Surface roughening: Use organic solvent to swell the plastic surface follow by strong oxidizing agent like chromic acid to roughen plastic surface (to increase surface area for catalyst absorption and improve adhesion between plastic and metal deposit) for subsequent catalyzation;

2. Catalyzation: Palladium is widely use as a catalyst to initiate electroless copper reaction. The catalyst is in palladium colloid structure for earlier to absorb on plastic surface;

3. Metallization: Electroless copper or nickel is widely use for POP. Electroless plating reaction can only start on catalyzed plastic surface. Different metal thickness is required for different application like EMI shielding, decorative, etc.

David Shiu
- Singapore
2006

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Ed. note: And here is the photo --

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2006

Thank you David for your answer, But the box that I want to plate is one side open. I mean I want to plate ONLY inside of the box as you see on the picture.
How can I plate only inside of it?
thank you again,

Tayyar BEK
- Istanbul, Turkey

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You could drop the box into a picture frame of the correct depth. with a rectangular hole of the correct size, so that when you spray it, only the inside is exposed to the spray. You could spray a two-part silvering solution on it.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

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Thank you Mr.Mooney for your answer, but here, we have hundreds of thousands of this box. and I couldn't understand exactly what to do.

I appreciate for your interest.

Tayyar BEK
- Istanbul, Turkey
2006

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Having a great many to do may justify automation, or paying experienced people to participate in a brainstorming session, and going about the planning in a highly organized fashion, Tayyar.

Step 1 is the chemistry. You must determine why the metallization is required, and consequently exactly what kind of metallization you need. Do you need a super high quality plating-on-plastic preparation cycle as described by David? Or will simple two-part silver spraying be good enough? Maybe vacuum metallization with aluminum will give you the conductivity you need if it is for electronic noise reduction and there are no exposure issues; this is inexpensive enough that it is applied to disposable party balloons. Could a shiny foil be applied with adhesive [adv: adhesive spray on eBay or Amazon] -- either aluminum foil or vacuum metallized mylar film? Maybe a "chrome-look paint" would work.

After you have decided upon the required properties of the conductive layer, then you can determine which technologies can deliver it. With the technology chosen, then you work out the details of how to keep the reflective material from getting on the outside of the box; this could be trivial if the application technology will be to use adhesive foil, and more difficult if the box must be immersed in a reactive liquid. After you know the required properties, and the application technology, and the shielding method, then you can think about automation machinery. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

Why jeopardize your project trying to save through a free but limited internet chat? As Ted says, volume justifies automation AND engineering also. If you are not capable to develop a painting method or set up a POP line or whatever by yourself, why not hire a consultant to tell you how? With so many boxes, the fees will not be significant.

Guillermo Marrufo
Monterrey, NL, Mexico
2006

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2006

Mr Tayyar Bek
you can't plate that box yourself because plating on plastic is a very complex job. Plating process steps:
-etching
-neutralizing
-activation 1
-activation 2
-electroless nickel plating
-DULL NICKEL PLATING
-acid copper plating
-bright nickel plating
-chrome plating

if you want plating only inside of the box; you must isolate surface with isolation band or chemical.

best regards.

Murat Cetin
- Izmir, TURKEY