Authoritative research institute IHS recently pointed out that AMOLED displays have been in mass production for many years, but the industry's long-awaited foldable screen has never appeared. One of the important bottlenecks is the cover material.

The application of transparent polyimide (PI) materials on foldable OLED screens is highly expected. The industry generally agrees that the solution of transparent PI + hard coating has the most potential.

Both Samsung and LG Display are actively developing such solutions and laying out corresponding supply chains.

PI film is made from pyromellitic dianhydride (PMDA) and diaminodiphenyl ether (ODA) in a solvent through polycondensation and casting into a film and then imidized. Material, with high strength and toughness, wear resistance, high temperature resistance, corrosion resistance and other special properties, has become one of the important raw materials of the two major areas of electronic motor upstream。

Although the PI film meets the conditions of being sufficiently thin, bendable, and resistant to high temperatures, the ordinary PI is light yellow and certainly cannot be used as a cover. Therefore, colorless and transparent PI has become the key to development. But there are not many transparent PIs, and developing colorless, transparent, and stable PIs has become a very challenging task.

In 2016, Kolon Industries pioneered the development of transparent polyimide, which is expected to accelerate the evolution of flexible screen phones. Founded in 1954, Korea KOLON is the first company to produce nylon in Korea. At present, Samsung, LG and other display makers are its customers.

It is expected that the transparent PI developed this time is expected to replace the core material glass currently used for displays. And it has achieved an import substitution effect of more than 1 trillion won for South Korea.