Abstract: The present disclosure relates to a polyimide varnish composition for a flexible substrate and a polyimide film using the same, and a polyimide varnish composition for a flexible substrate according to the present disclosure may include an acid anhydride including 3,3?,4,4?-biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic dianhydride (PMDA), and a diamine. The polyimide varnish composition according to the present disclosure has the advantage of being able to manufacture a polyimide film having heat resistance, high flexural properties, and high flexibility by increasing elongation while having a low coefficient of thermal expansion.

Abstract: The present disclosure relates to a polyimide varnish composition for a flexible substrate and a polyimide film using the same, and a polyimide varnish composition for a flexible substrate according to the present disclosure may include an acid anhydride including 3,3?,4,4?-biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic dianhydride (PMDA), and a diamine. The polyimide varnish composition according to the present disclosure has the advantage of being able to manufacture a polyimide film having heat resistance, high flexural properties, and high flexibility by increasing elongation while having a low coefficient of thermal expansion.

Abstract: The present disclosure relates to a polyimide film for a flexible metal clad laminate and a flexible metal clad laminate including the same, and an aspect of the present disclosure is to provide a polyimide film for a flexible metal clad laminate, which is derived from a polyimide precursor composition including an acid dianhydride and a diamine, in which the acid dianhydride includes 70% by mol or more of pyromellitic dianhydride (PMDA), and the diamine includes m-tolidine and dimer diamine.

Abstract: Provided are a multi-layer flexible metal-clad laminate, and a manufacturing method thereof, and more particularly, a multi-layer flexible metal-clad laminate in which at the time of manufacturing a multi-layer polyimide film on a surface of a metal-clad having a predetermined surface roughness value (Rz, Ra) and having roughening particles having a predetermined size or less attached thereon, a multi-coating scheme is used to form each polyimide mixed layer, such that a light reflection on a surface of the polyimide film and a light reflection generated at an interlayer interface of the polyimide in the multi-layer polyimide film are decreased to have an improved light transmittance of a polyimide laminate film after the metal-clad is removed, and a manufacturing method thereof.