Mylar: Meaning (information, definition, explanation, facts)

Mylar® is a trade name of DuPont Teijin Films of Hopewell, VA for biaxially-oriented polyethylene terephthalate (BOPET) polyester film used for its high tensile strength, chemical and dimensional stability, transparency, and electrical insulation. A variety of companies manufacture BOPET and other polyester films under different trade names, but Mylar is often employed as a generic designation for these, as in "Mylar capacitor" or "Mylar balloon."

Mylar was developed by DuPont in the mid-1950s. In 1960, NASA launched the Echo satellite, a 100-foot diameter balloon of metallized 0.005-inch thick Mylar® film.

Common uses for BOPET films include:

• An overlay over a map, on which additional data, or copied data, can be drawn without damaging the map
• Performance sails for sailboats
• An electrical insulating material
• As base material for magnetic tapes (audio/video tape etc.)

In manufacture, a film of molten PET is cast on a roll and subsequently stretched in and orthogonal to the direction of travel. One of its sides is microscopically smooth, while the other side contains microscopic asperities which promote adhesion of coatings and printing media.