TRANSPARENT POLYIMIDE FILM

• US 20200131313A1
• Filed: 10/18/2019
• Published: 04/30/2020
• Est. Priority Date: 10/30/2018
• Status: Active Grant

• Current Assignee: Taimide Tech., Inc.
• Original Assignee: Taimide Tech., Inc.
• Inventors: Ho, Yi-Hsueh, Liu, Yi-Ting
• Granted Patent: US 11,530,297 B2
• Time in Patent Office: Days
• CPC Class Codes: C08G 73/1007 from tetracarboxylic acids or derivatives and diamines
• CPC Class Codes: C08G 73/1032 characterised by the solvent(s) used
• CPC Class Codes: C08G 73/1039 comprising halogen-containing substituents
• CPC Class Codes: C08G 73/1042 Copolyimides derived from at least two different tetracarboxylic compounds or two different diamino compounds
• CPC Class Codes: C08G 73/1067 Wholly aromatic polyimides, i.e. having both tetracarboxylic and diamino moieties aromatically bound
• CPC Class Codes: C08G 73/1071 Wholly aromatic polyimides containing oxygen in the form of ether bonds in the main chain
• CPC Class Codes: C08G 73/1078 wholly aromatic in the diamino moiety
• CPC Class Codes: C08G 73/123 the unsaturated precursors comprising halogen-containing substituents
• CPC Class Codes: C08G 73/126 the unsaturated precursors being wholly aromatic
• CPC Class Codes: C08G 73/127 containing oxygen in the form of ether bonds in the main chain
• CPC Class Codes: C08J 2379/08 Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: C08J 5/18 Manufacture of films or sheets
• CPC Class Codes: C09D 179/08 Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors

Abstract

A transparent polyimide film, prepared from a copolymerized polyamide acid according to a chemical cyclization method, is provided. The copolymerized polyamide acid requires at least a semi-aromatic polyamide acid, and the semi-aromatic polyamide acid is formed by reacting cyclobutane-1,2,3,4-tetracarboxylic dianhydride (CBDA) and 2,2′-bis(trifluoromethyl)diaminodiphenyl (TFMB). The molar number of dianhydrides of the semi-aromatic polyamide acid is more than 20% of the total molar number of anhydrides of the copolymerized polyamide acid, so that the transparent polyimide film has a light transmittance greater than 80%, a chroma b* less than 5, and a CTE less than 35 ppm/° C.

Claims

1. A transparent polyimide film prepared from a copolymerized polyamide acid by a chemical cyclization method, wherein the copolymerized polyamide acid includes a semi-aromatic polyamide acid, and the semi-aromatic polyamide acid is formed by reacting cyclobutane-1,2,3,4-tetracarboxylic dianhydride (CBDA) and 2,2′

-bis(trifluoromethyl)diaminodiphenyl (TFMB), wherein the molar number of dianhydrides of the semi-aromatic polyamide acid is more than 20% of the total molar number of anhydrides of the copolymerized polyamide acid, so that the transparent polyimide film has a light transmittance greater than 80%, a chroma b* less than 5, and a CTE less than 35 ppm/°

C.

2. The transparent polyimide film according to claim 1, wherein the copolymerized polyamide acid further includes an aromatic polyamide acid, and the aromatic polyamide acid is obtained by reacting an aromatic diamine and an aromatic anhydride.

3. The transparent polyimide film according to claim 2, wherein the aromatic diamine is 2,2′

-bis(trifluoromethyl)benzidine (TFMB), 2,2′

-bis[4-(4-aminophenoxyphenyl)]propane (BAPP), 2,2-bis [4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3 -hexafluoropropane (HFBAPP), 5(6)-amino-1-(4-aminophenyl)-1,3,3-trimethylindan (TMDA), p-phenylenediamine (PDA), 4,4′

-bis(4-aminophenoxyl)biphenyl (BAPB), 2,2′

-bis(trifluoromethyl)-4,4′

-diaminophenyl ether (6FODA), 4,4′

-bis(4-aminophenoxyl)diphenyl sulfone (BAPS), 9,9-bis(4-aminophenyl)fluorene (BAFL), 4,4′

-diaminodiphenyl sulfone (44DDS), 4,4′

-diaminodiphenyl ether (ODA), 4,4′

-diaminobenzophenidine (44DABA), 2,2-bis(4-aminophenyl)hexafluoropropane (Bis-A-AF), m-phenylenediamine (mPDA), 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (6FAP), 3,5-diaminobenzoic acid (35DABA), 2-(4-aminophenyl)-5-aminobenzoxazole (SBPOA), 1,4-bis(4-aminophenoxyl)benzene (TPEQ), or 4,4′

-[1,4-phenylbis(oxygen)]bis [3-(trifluoromethyl)aniline] (FAPB).

4. The transparent polyimide film according to claim 2, wherein the aromatic dianhydride is 1,2,4,5-benzenetetracarboxylic anhydride (PMDA), 3,3′

,4,4′

-biphenyltetracarboxylic dianhydride (BPDA), 4,4′

-oxydiphthalic anhydride (ODPA), 3,3′

,4,4′

-benzophenonetetracarboxylic dianhydride (BTDA), 3,3,4,4-diphenylsulfone tetracarboxylic anhydride (DSDA), 2,3,3′

,4′

-biphenyltetracarboxylic dianhydride (α

-BPDA), 4,4-hexafluoro isopropyl phthalic anhydride (6FDA), or 4,4′

-(4,4′

-isopropyldiphenoxy)diphthalic anhydride (BPADA).

5. The transparent polyimide film according to claim 1, wherein the transparent polyimide film has a thickness of 10-80 μ

m.