Patent ID: 11898009
Assignee: UBE CORPORATION
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C  H  G  Y | IPC C  G  H

Claim 3:
4. A polyimide precursor comprising a repeating unit which is obtainable by reacting:
a tetracarboxylic acid component (A) comprising at least 3,3′, 4,4′-biphenyltetracarboxylic dianhydride, and
a diamine component (B) comprising:
(B-1) at least one diamine selected from the group consisting of 1,4-diaminobenzene, [1.1′: 4′,1″-terphenyl]-4,4″-diamine, and 1,4-bis [2-(4-aminophenyl)-2-propyl]benzene, and
(B-2) at least one diamine selected from the group consisting of 9,9-bis (4-aminophenyl) fluorene, 4,4′-(49H-fluorene-9,9-diyl)bis([1,1′-biphenyl]-5,2-diyl))bis(oxy))diamine, and 4,4′-([1,1′-binaphthalene]-2,2′-diylbis(oxy))diamine,

with the proviso that when the diamine component (B) comprises 1,4-diaminobenzene and 9,9-bis(4-aminophenyl)fluorene), the amount of diamine compound(s) other than the diamine of (B-1) and the diamine (B-2) is 20 mol % or less, with the proviso that the repeating unit does not include a Si-containing group.