Electrical tapes, used for electrical and electronic applications, are designed to withstand an applied voltage and must meet strict dielectric strength standards.  In North American, UL Underwriters Laboratories and CSA, Canada Standards Associations set the minimum acceptance standards.  Some electrical tapes are used in OEM, original equipment manufacturers, applications in a factory setting and some are used by electricians in the field.  Where ever they are applied, using the correct tape is critical for success. 

While most people think of electrical tape to be a PVC, polyvinyl chloride tape, like 3M Super 33+, electrical tapes are supplied with backings other than PVC.  PVC tape is desired for field installed electrical insulation because it is flexible, conformable, rather tacky and can be torn by hand.  In OEM applications, other backings with other properties solve other types of electrical problems.  For example, a tape backing of fiberglass cloth is combined with rubber, acrylic or silicone thermosetting adhesives to provide mechanical overwrap protection on coils, toriods and magnet wire.  Other backings such as polyester film, polyimide film also known as Kapton, FEP fluorinated ethylene propylene, PTFE polytetrafluoroethylene and PTFE coated fiberglass films have a high dielectric strength and withstand high temperatures. 

Polyester film tape is made in a variety of colors and with rubber, acrylic and silicone adhesives.  Polyester, also know by its generic term, PET polyethylene terephthalate is a very tough, difficult to tear, puncture resistant film.  PET is also the raw material used to blow mold 2 liter pop bottles.  Those bottles, flex and bend and crinkle, however they seldom leak because of this torture.