CONFORMAL COATINGS FOR PRINTED CIRCUIT ASSEMBLIES
Abstract
Commercially available epoxy and polyurethane resin conformal coatings were evaluated as protective coatings on glass-epoxy and paper-epoxy Cu-clad laminate printed circuit boards. All the epoxy and polyurethane coatings tested met the following characteristics: (1) suitability for dip, spray on brush coat application, (2) transparency when full cured, (3) cured within 2 hr at 75 C, (4) did not support fungus, and (5) one component system preferred. No blistering, wrinkling, cracking or corrosion was observed; good adhesion to test panels was obtained. The dielectric constant decreased with increasing frequency from 1 to 100 mc. The Q factor of the epox coated boards decreased as compared to the uncoated boards. All coated specimens passed the initial dielectric withstanding voltage test before thermal cycling.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 31, 1961
- Accession Number
- AD0266884
Entities
People
- Anthony J. Beccasio
Organizations
- Motorola Mobility