After the start of the commercial production of naphthalenedicarboxylic acid (NDC) as the raw material of PEN by the hands of US Amoco Chemical Co. in 1995, the trial of application of PEN resin to molding product field started, and this resin came to be used in various fields. Teijin Group started the research and development of PEN resin in 1964, 31 years precedential to the above event, and it has continuously been engaging without a break in the development of application of the resin to molding material, biaxially-oriented film, and fibrous material. As early as 1971, we commercialized PEN film, and developed a new process for raw material synthesis. It is not an exaggeration to say that the history of PEN development by Teijin is the history of PEN all over the world.

PEN is crystalline thermoplastic polyester with the skeleton chain of polycondensation product composed of naphthalenedicarboxylic acid as an acid component and ethylene glycol as a glycol component. It is manufactured in the same way as polyethylene terephthalate (PET) as typical polyester, and injection molding processing is also performed in the same way. However, the performance of PEN is evaluated one rank higher than that of PET. Although PEN is originally crystalline resin, crystalline velocity is slow, and transparent molding product can easily be obtained. For this reason, this resin is utilized as functional members for industrial parts, food packaging, medical product packaging, etc.