FORMULATED POLYURETHANE RESIN COMPOSITIONS FOR FLOOD COATING ELECTRONIC CIRCUIT ASSEMBLIES

摘要

Electrical circuit assemblies flood coated with polymeric flood coat compositions as described or exemplified herein are provided. The flood coat composition is characterized as having a sufficient gel time and thixotropic index as to substantially cover or encapsulate the electrical circuit assembly as a fixed mass upon cure such that the thickness of the polymeric coating on surfaces horizontal to the assembly is from 20 mils to 75 mils, and the thickness on surfaces vertical to the assembly is from 4 mils to 20 mils. Such flood coated assemblies and devices containing same are advantageous over conventional potting materials or conformal coatings because they require less material thereby reducing weight and cost, and they are able to withstand extreme environmental stresses such as from temperature and/or vibrations.