Lg Chem, Ltd

Ye Ji Hong

Jinyoung Park

Danbi Choi

Hye Won Jeong

Jinho Lee

Chan Hyo Park

Kyunghwan Kim

A polyimide film according to the present invention can be effectively used as a substrate for a flexible display device without a deterioration in heat resistance even at a temperature of 350&#xb0; C. or higher since a coefficient of thermal expansion (A) in the section of 100-350&#xb0; C., of the polyimide film, and a coefficient of thermal expansion (B) in the section of 350-450&#xb0; C., of the polyimide film, meet 0&#x3c;B/A&#x3c;2.

Polyimide film for flexible display device substrate

The present invention provides a display substrate polyimide film having: remarkably improved insulation characteristics; inner pores, included in the polyimide film, of which the maximum size is 10 nm or less; and a high maximum dielectric breakdown voltage of 350 V/&#x3bc;m or more. The polyimide film according to the present invention has improved insulation characteristics so as to be capable of suppressing the generation of a current fluctuation of TFTs according to the long-term driving of a TFT device in a display such as an OLED, thereby enabling the deterioration of the contrast of a display to be reduced.

Display substrate polyimide film

Growing community of inventors

Daejeon, South Korea

Ye Ji Hong