Hi John, Read through some other responses. I have had similar experiences to those already mentioned. One thing that I didn't see mentioned was the alternative of electroless plating. Electroless plating consists of three major processes.
1. The plastic parts are cleaned and "etched" by a solvent bath. 2. The plastic parts are then put into a catalyst bath which coats them uniformly with a reaction catalyst. 3. The plastic parts are then put into a plating bath where the catalyst reacts with the bath to plate solid metal onto the parts. There are two sub-steps here. One to plate Copper directly on the plastic; and one to plate Nickel over the Copper (for durability and corrosion resistance). We had product samples put through this process back in 1996. The surface resistivity, uniformity and durability were excellent. Electroless plating gets a uniform coverage of conductive material into corners and small features of the plastic. Our units were a split plastic case with an overlapping center joint. The plating could withstand many mating/unmating cycles without degrading. What was the drawback? We didn't have enough volume to make it cost effective. The process requires masks to be made; and the masks aren't cheap. In short, the per part cost was comparable or even less than conductive spray coating, but the tooling cost was higher (I seem to remember around $6,000). Another drawback is that the coating isn't as good if you need to selectively coat parts (i.e. coat some areas while leaving others bare). At the time, the process was called "Enshield" and it was being marketed by Enthone, New Haven, CT, PHONE: 203-934-8611, FAX: 203-937-1680. Fair warning...these phone numbers are five years old. I don't know if they're still good, you may very well call them and get an answer from Samuri Delicatessen. Chris > -----Original Message----- > From: John Juhasz [SMTP:jjuh...@fiberoptions.com] > Sent: Monday, August 20, 2001 2:30 PM > To: 'emc-p...@ieee.org' > Subject: Conductive Coatings > > > > Greetings . . . > > Beginning to consider conductive coatings for EMC shielding. > To be used inside a plastic cover (material as yet unknown) in > a low power/voltage (SELV) application. > This is unfamiliar territory. > > I'm sure someone on this listserv has experience with these. > I know to at least consider shielding effectiveness, material > compatibility (plastic housing material to coating), and > end-user environment. What are some other critical criteria? > > Thanks. > > John A. Juhasz > Product Qualification & > Compliance Engineer > > Fiber Options, Inc. > 80 Orville Dr. > Suite 102 > Bohemia, NY 11716 USA > > Tel: 631-419-2324 (direct) > Fax: 631-567-8322 > > > > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Michael Garretson: pstc_ad...@garretson.org > Dave Heald davehe...@mediaone.net > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://www.rcic.com/ click on "Virtual Conference Hall," > ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
