Barbara: Parylene(paraxylylenes)coatings are certainly very good possibly the best. It uses a dimer applied by vapor condensation as opposed to a liquid polymer for the other types of conformal coatings. However it is quite expensive when compared to some of the other common conformal coating materials such as acrylic and polyurethane's. Instead of plunging into ten pages of the pluses and minuses of each coating lets step back and define what the requirement is for your product. 1. What are the environmental conditions that it will be exposed to, temperature, chemicals, corrosive atmosphere, humidity? 2. What are the electrical requirements, voltage, insulation resistance, dielectric strength, dissipation factor, dielectric constant? 3.Do you require a uniform coating of a given thickness over the entire assembly? 4.What is the maintainable cleanliness level of the assembly prior to coating? 5.How will you do rework and recoat? 6. Do you have any $ cost constraints? 7. How do you know you need a conformal coating? This list can go on and on but I think you see the idea. I have no doubt the parylene coating would probably work great for you but it may be overkill. The better you can define your design requirements the wiser choice you can make if a coating is needed. Regards Michael Barmuta Staff Engineer Fluke Corp. Everett WA 425-446-6076 -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Barbara Burcham Sent: Monday, May 16, 2005 2:56 PM To: [log in to unmask] Subject: [TN] Conformal Coating of Assembled Boards Well, my company now has an application requiring conformal coating on some small assembled boards. We need to mask off 3 connectors and coat everything else. I have some information on a product called Parylene applied by Parylene Coating Services, Inc. in Katy, Texas. We did a small lot with a simple spray-on process, but that is not the way to do production runs, of course. What would you recommend? Thanks, Barbara Barbara J. Burcham, C.I.D. Fairfield Industries, Inc 281-275-7687 [log in to unmask] --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------