HOME FAQs BOOKS JOBS: Help Wanted Suggestions you are here: Hotline/Forum => Letter 38074

Need a maskant to withstand 190deg; F and pH 12 plating process

+++++

We need a maskant that will withstand 190F plating bath temperature and 12 ph solution. we need to hold .020 tolerance and are having trouble with our existing maskant not leaking when exposed to these conditions. Any advise would be much appreciated.
Sincerely,

Patti Kientz
Plating company - Santa Ana, California, USA

First of two simultaneous responses -- +++++

What you are currently using would be a nice place to start. What else have you tried. What is the shape and finish of the part. Can you use solvent to remove the mask? What other constraints can you think of?

James Watts
- Navarre, Florida

Second of two simultaneous responses -- +++++

Most maskants are photopositive materials and are designed to operate at low pH and to be developed (or stripped) in high pH solvents. What you need is exactly the opposite, namely a photonegative photoresist that can be used at high pH and is processed with low pH solvents. You can get some basic formulations from textbooks on the subject, but the intricacies of photoresists are such that you will almost certainly need technical backup. It is therefore better to ask a professional supply house for their products. Try asking Kodak or one of the other photoresist suppliers for further advice.

Trevor Crichton
R&D practical scientist The Pheasantries - Chesham, U.K.

ANSWER or FOLLOW UP POST an unrelated QUESTION HOT Topics

Disclaimer: It is not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information
presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The
internet is largely anonymous; some names may be fictitious and some recommendations may be deliberately harmful.

If you are seeking a product or service related to metal finishing, please check these Directories: