Abstract: This invention provides an insulating protective material effective for protection of electronic and electric devices such as electronics elements. This insulating protective material contains at least one hydrous oxide of a metal which has ion exchange properties together with a fusion bonding component such as low-melting glass, epoxy resin, phenolic resin, silicone resin, etc. and a filler such as fused silica, .beta.-eucryptite, glass fiber, glass beads, etc.Said specific hydrous oxide can be used together with a sulfur-containing organic high molecular weight compound.The hydrous oxides used in protective materials as a sealing material for electronic and electric devices can capture an ionic impurity eluted from the components of the protective material and fix it therein thereby to provide stable electronic materials excellent in performance.