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Pigment/ink that will stick to plastic/stainless steel/porcelein

August 12, 2009

I am looking for a pigment/ink that will be able to stick to various surfaces i.e. plastic/stainless steel/porcelein etc.

Any idea where I can start looking?

Dave

Dave Coates
- Port Elizabeth, Eastern Cape, South Africa

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August 14, 2009

I know it may not be the answer you want but if you want this to be permanent, don't start looking at your pigment start looking at your substrates. (Hey, this is a finishing website after all). Changing an ink may not help if your surfaces are not suitably prepared.
The key to getting things to stick to a substrate is surface free energies and metals tend to have very high surface free energies whereas polymers and ceramics are very low.
You may not need anything too flash in terms of ink if you treat your surfaces correctly. Try doing what is termed a water break free test on your surfaces. Put water on the material and check if it breaks up into droplets. Then try just rubbing the surface with something like scotchbrite and try it again. If the material breaks up into droplets it is more than likely it will also repell any ink. If it stays as a solid film you are more likely to have some success.
Flame activation is used for some polymers, (very briefly passing a blowtorch over the surface). Cold plasmas are also very effective. maybe you could link something up with an inkject dot printer on a moving line.

Ciaron Murphy
Aerospace - South Wales UK