POLYIMIDE PRECURSOR AND POLYIMIDE
A polyimide precursor comprising a repeating unit represented by the following chemical formula (1): in which A is a tetravalent group having at least one aliphatic six-membered ring and no aromatic ring in the chemical structure, and B is a divalent group having at least one amide bond and an aromatic ring in the chemical structure; or A is an aliphatic tetravalent group and B is a divalent group having at least one chemical structure represented by the following chemical formula (2) in the chemical structure: and X 1 and X 2 are each independently hydrogen, a C 1-6 alkyl group or a C 3-9 alkylsilyl group.
1 . A polyimide precursor comprising a repeating unit represented by the following chemical formula (1):
wherein A is a tetravalent group having at least one aliphatic six-membered ring and no aromatic ring in the chemical structure, and B is a divalent group having at least one amide bond and an aromatic ring in the chemical structure; or A is an aliphatic tetravalent group and B is a divalent group having at least one chemical structure represented by the following chemical formula (2) in the chemical structure:
and X 1 and X 2 are each independently hydrogen, a C 1-6 alkyl group or a C 3-9 alkylsilyl group.
2 . The polyimide precursor according to claim 1 , wherein A is at least one selected from the group consisting of the following chemical formulae (3-1) to (3-4):
wherein R1 is a direct bond, a CH 2 group, a C(CH 3 ) 2 group, an SO 2 group, an Si(CH 3 ) 2 group, a C(CF 3 ) 2 group, an oxygen atom or a sulfur atom;
wherein R2 is a CH 2 group, a CH 2 CH 2 group, an oxygen atom or a sulfur atom;
wherein R3 and R4 are each independently a CH 2 group, a CH 2 CH 2 group, an oxygen atom or a sulfur atom.
3 . The polyimide precursor according to claim 1 , wherein B is at least one selected from the group consisting of the following chemical formulae (4-1) to (4-4):
wherein Ar 1 , Ar 2 and Ar 3 are each independently a divalent group having an aromatic ring having 6 to 18 carbon atoms; and n1 is an integer of 0 to 5;
wherein Ar 4 , Ar 5 , Ar 6 , Ar 7 and Ar 8 are each independently a divalent group having an aromatic ring having 6 to 18 carbon atoms; and n2 is an integer of 0 to 5;
wherein Ar 9 , Ar 10 , Ar 11 , Ar 12 and Ar 13 are each independently a divalent group having an aromatic ring having 6 to 18 carbon atoms; and n3 is an integer of 0 to 5;
wherein Ar 14 and Ar 15 are each independently a divalent aromatic group having 6 to 18 carbon atoms; and R5 is a hydrogen atom or a monovalent organic group.
4 . The polyimide precursor according to claim 1 , obtained from a tetracarboxylic acid component providing the repeating unit represented by chemical formula (1) in an amount of 70 mole % or more and other tetracarboxylic acid components in an amount of 30 mole % or less based on 100 mole % of the total tetracarboxylic acid components, and a diamine component providing the repeating unit represented by chemical formula (1) in an amount of 70 mole % or more and other diamine components in an amount of 30 mole % or less based on 100 mole % of the total diamine components.
5 . The polyimide precursor according to claim 1 , obtained from a tetracarboxylic acid component having a purity of 99% or more and a diamine component having a purity of 99% or more, wherein in the case that plural stereoisomers are contained, the purity is determined by regarding the stereoisomers as a single component without distinguishing them.
6 . The polyimide precursor according to claim 1 , obtained from a tetracarboxylic acid component having a light transmittance of 70% or more and a diamine component having a light transmittance of 30% or more, wherein the light transmittance of the tetracarboxylic acid component is a transmittance at a wavelength of 400 nm and an optical path length of 1 cm as a 10% by mass solution in a 2 N sodium hydroxide solution, and the light transmittance of the diamine component is a transmittance at a wavelength of 400 nm and an optical path length of 1 cm as a 8% by mass solution in methanol, water, N,N-dimethylacetamide or acetic acid or hydrochloric acid solutions thereof.
7 . The polyimide precursor according to claim 1 having a light transmittance of 40% or more at a wavelength of 400 nm and an optical path length of 1 cm as a 10% by mass solution in a solvent selected from N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, dimethylsulfoxide and water.
8 . A polyimide precursor solution composition comprising the polyimide precursor according to claim 1 dissolved in a solvent, wherein the solvent has a light transmittance of 89% or more at a wavelength of 400 nm and an optical path length of 1 cm.
9 . A polyimide containing a repeating unit represented by the following chemical formula (5):
wherein A is a tetravalent group having at least one aliphatic six-membered ring and no aromatic ring in the chemical structure and B is a divalent group having at least one amide bond and an aromatic ring in the chemical structure; or A is an aliphatic tetravalent group and B is a divalent group having at least one chemical structure represented by the aforementioned chemical formula (2) in the chemical structure.
10 . The polyimide according to claim 9 , wherein A in the chemical formula (5) is an aliphatic tetravalent group; B is a divalent group having at least one chemical structure represented by the chemical formula (2) in the chemical structure; and the polyimide has an oxygen index of 22% (volume fraction) or more.
11 . A polyimide obtained through a reaction between an aliphatic tetracarboxylic acid component and a diamine component and having an oxygen index of 22% (volume fraction) or more.
12 . A substrate for a display, a touch panel or a solar battery formed of from the polyimide obtained from the polyimide precursor solution composition according to claim 8 .
13 . A substrate for a display, a touch panel or a solar battery formed from the polyimide according to claim 9 .