Transparent polyimide film

[0024][Preparation of a Copolymerized Polyamide Acid Solution]

[0025]20.1 g of TFMB (0.0627 mole, 0.315 of the total diamine molar ratio) is added to 412.5 g of DMAc, 11.723 g of CBDA (0.0598 mole, 30% of the total anhydride molar percentage) is added after complete dissolution, and the reaction is performed for 6 h while stirring, and the temperature is continuously maintained at 25° C. to obtain a semi-aromatic polyamide acid solution. 43.711 g of TFMB (0.1365 mole) is added to the semi-aromatic polyamide acid solution and is stirred until being completely dissolved, and 61.965 g of 6FDA (0.1395 mole) is added, and dissolution and reaction are performed after stirring for a certain period of time, and the temperature of the solution is maintained at 25° C., to finally obtain the copolymerized polyamide acid solution having a solid content of 25%.

[0026][Preparation of a Transparent Polyimide Film]

[0027]54.4 g of the copolymerized polyamide acid solution is taken out, and the solid cont

[0029][Preparation of a Copolymerized Polyamide Acid Solution]

[0030]27.800 g of TFMB (0.0868 mole, 0.42 of the total diamine molar ratio) is added to 412.5 g of DMAc, 16.214 g of CBDA (0.0827 mole, 40% of the total anhydride molar percentage) is added after complete dissolution, and the reaction is performed for 6 h with stirring, and the temperature is continuously maintained at 25° C. to obtain a semi-aromatic polyamide acid solution. 38.391 g of TFMB (0.120 mole) is added to the semi-aromatic polyamide acid solution and is stirred until completely dissolved, and 55.094 g of 6FDA (0.124 mole) is added, and dissolution and reaction are performed after stirring for a certain period of time, and the temperature of the solution is maintained at 25° C., to finally obtain the copolymerized polyamide acid solution having a solid content of 25%.

[0031][Preparation of a Transparent Polyimide Film]

[0032]54.4 g of the copolymerized polyamide acid solution is taken out, and the solid content is d

[0033][Preparation of a Copolymerized Polyamide Acid Solution]

[0034]42.972 g of TFMB (0.1342 mole, 0.625 of the total diamine molar ratio) is added to 412.5 g of DMAc, 21.053 g of CBDA (0.1074 mole, 50% of the total anhydride molar percentage) is added after complete dissolution, and the reaction is performed for 6 h with stirring, and the temperature is continuously maintained at 25° C. to obtain a semi-aromatic polyamide acid solution. 25.783 g of TFMB (0.0805 mole) is added to the semi-aromatic polyamide acid solution and is stirred until completely dissolved, and 47.691 g of 6FDA (0.1074 mole) is added, and dissolution and reaction are performed after stirring for a certain period of time, and the temperature of the solution is maintained at 25° C., to finally obtain the copolymerized polyamide acid solution having a solid content of 25%.

[0035][Preparation of a Transparent Polyimide Film]

[0036]54.4 g of the copolymerized polyamide acid solution is taken out, and the solid content i