Insulating varnish-factors to consider in choosing the right solvent

The author first reviews the key terms that are a standard part of the varnish manufacturer´s vocabulary. He then presents a brief history of insulating varnishes, including Rule 66, water-borne, and solventless varnishes. It is emphasized that the perfect varnish does not exist. Some of the most desirable properties in an insulating varnish, i.e. fast cure, excellent stability, zero pollution, nonflammability, low cost, and low toxicity, put conflicting demands on the formulator. They cannot all be optimized in the same package. It is concluded that a good understanding of the `language of varnish´ will help in picking the best one for a particular user