It can be made of many plastics but PVC (polyvinyl chloride, "vinyl") is the most popular, as it stretches well and gives effective and long-lasting insulation.In the early 1940s, vinyl plastic emerged as a versatile material for a wide range of applications, from shower curtains to cable insulation.Unfortunately, TCP tended to migrate, giving the surface of the vinyl film an oily quality and degrading every tape adhesive known.Research chemists and engineers at 3M set out to create a dependable, pressure-sensitive tape made of a vinyl film that would have the required electrical, physical and chemical properties.Finally, in January 1946,[5] inventors Snell, Oace, and Eastwold of 3M applied for a patent for a vinyl electrical tape with a plasticizer system and non-sulfur-based rubber adhesive that were compatible.
