Shellac‐based insulating varnishes

Insulating varnishes are widely used for coating of armatures/coils of electric motors, transformers and also for finishing electrical components. Natural resin shellac finds considerable use in the manufacture of insulating varnishes. Improved dielectric properties have been obtained for varnishes prepared from shellac modified with synthetic resins, drying oils etc. The present article provides information about the researchers so far carried out on both the air‐drying and baking type of insulating varnishes based on shellac.