Endless tubular polyimide film

A semi-conductive seamless tubular polyimide film, wherein

• carbon black is dispersed in polyimide having at least two aromatic tetracarboxylic acid components having a mixture of 15 to 55 mol % of asymmetric aromatic tetracarboxylic acid component and 85 to 45 mol % of symmetric aromatic tetracarboxylic acid component and at least one aromatic diamine component, the semi-conductive seamless tubular polyimide film having a surface resistivity of 103 to 1015 Ω/sq.

A method for producing a seamless tubular polyimide film, comprising:

• rotationally molding a mixed solution substantially in a monomeric state having a mixture of an aromatic tetracarboxylic acid component comprising 15 to 55 mol % of asymmetric aromatic tetracarboxylic acid and/or ester thereof and 85 to 45 mol % of symmetric aromatic tetracarboxylic acid and/or ester thereof and an approximately equimolar amount of an aromatic diamine component, to form a tubular shape, and
• imidizing the tubular material by heating.

A method for producing a semi-conductive aromatic amic acid composition comprising:

• subjecting at least two aromatic tetracarboxylic acid derivatives and an approximately equimolar amount of at least one aromatic diamine to partial condensation polymerization in an organic polar solvent, thereby yielding an aromatic amic acid oligomer solution;
• and
• uniformly mixing electrically conductive carbon black powder with the oligomer solution.

A semi-conductive polyimide-based precursor composition, wherein carbon black is uniformly dispersed in a mixed solution prepared by mixing a high-molecular-weight polyimide precursor solution or high-molecular-weight polyamideimide solution in a nylon salt monomer solution in which at least two aromatic tetracarboxylic acid diesters and an approximately equimolar amount of at least one aromatic diamine are dissolved in an organic polar solvent.

A method for producing a semi-conductive polyimide-based precursor composition, comprising:

• mixing a high-molecular-weight polyimide precursor solution or high-molecular-weight polyamideimide solution in a nylon salt monomer solution in which at least two aromatic tetracarboxylic acid diesters and an approximately equimolar amount of at least one aromatic diamine are dissolved in an organic polar solvent to prepare a mixed solution, and
• uniformly dispersing carbon black in the mixed solution.

A method for producing a high-concentration semi-conductive polyimide precursor composition, comprising:

• uniformly dispersing carbon black in an organic polar solvent to give a carbon black dispersion and
• dissolving aromatic tetracarboxylic acid diester and an approximately equimolar amount of aromatic diamine in the carbon black dispersion.