Polyimide precursor and polyimide

Abstract

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 .