Abstract: A process for producing a polyimide platy object includes (a) providing a solution containing a solvent and a solute (i.e., a polyimide precursor or polyimide); (b) pouring the solution onto a supporting member; (c) removing a portion of the solvent from the solution at a first temperature lower than boiling point of the solvent, thereby forming a precursory platy object thereon, the precursory platy object having a self-supporting property and a first surface in contact with the supporting member and a second surface away therefrom and a first content of the solvent at the first surface and a second content (less than the first content by 2-10 wt %) of the solvent at the second surface; and (d) detaching the precursory platy object therefrom; and (e) heating the precursory platy object at a second temperature higher than boiling point of the solvent and is lower than decomposition temperature of the polyimide.

Abstract: A process for producing a polyimide platy object includes (a) providing a solution containing a solvent and a solute (i.e., a polyimide precursor or polyimide); (b) pouring the solution onto a supporting member; (c) removing a portion of the solvent from the solution at a first temperature lower than boiling point of the solvent, thereby forming a precursory platy object thereon, the precursory platy object having a self-supporting property and a first surface in contact with the supporting member and a second surface away therefrom and a first content of the solvent at the first surface and a second content (less than the first content by 2-10 wt %) of the solvent at the second surface; and (d) detaching the precursory platy object therefrom; and (e) heating the precursory platy object at a second temperature higher than boiling point of the solvent and is lower than decomposition temperature of the polyimide.

Abstract: The invention relates to a fluorine-containing polybenzoxazole including a structural unit represented by the general formula (1): where X is a tetravalent organic group containing an aromatic ring, and two sets of N and O are each bonded to the ortho positions of the aromatic ring of X such that two five-membered rings are formed next to the aromatic ring of X. This polybenzoxazole demonstrates low dielectric constant and low coefficient of thermal expansion while maintaining the properties of polybenzoxazole including mechanical strength and thermal stability.

Abstract: The invention relates to a fluorine-containing polybenzoxazole including a structural unit represented by the general formula (1): 1

Abstract: The invention relates to a fluorine-containing polybenzoxazole including a structural unit represented by the general formula (1): where X is a tetravalent organic group containing an aromatic ring, and two sets of N and O are each bonded to the ortho positions of the aromatic ring of X such that two five-membered rings are formed next to the aromatic ring of X. This polybenzoxazole demonstrates low dielectric constant and low coefficient of thermal expansion while maintaining the properties of polybenzoxazole including mechanical strength and thermal stability.

Abstract: A polyimide precursor composition which is produced by (i) providing a polyamide acid solution obtained by reacting an aromatic tetracarboxylic acid component and a diamine component in the presence of an oxygen-containing solvent and (ii) subjecting said polyamide acid solution to heat treatment. The polyimide precursor composition exhibits a desirable apparent viscosity and a desirable thixotropic property and it excels in film forming ability, and because of this, it enables the formation a high quality relief pattern film with no defect and which excels in form retention by way of the screen printing.

Abstract: A polyimide precursor composition which is produced by (i) providing a polyamide acid solution obtained by reacting an aromatic tetracarboxylic acid component and a diamine component in the presence of an oxygen-containing solvent and (ii) subjecting said polyamide acid solution to heat treatment. The polyimide precursor composition exhibits a desirable apparent viscosity and a desirable thixotropic property and it excels in film forming ability, and because of this, it enables the formation a high quality relief pattern film with no defect and which excels in form retention by way of the screen printing.

Abstract: A polyimide precursor composition solution includes a tetracarboxylic acid component containing not less than 70 mol % of at least one selected from the group consisting of benzenetetracarboxylic acid and its reactive derivatives; a maleimide compound; and a diamine component containing not less than 70 mol % of 2,2'-substituted-4,4'-benzidine represented by the general formula (I) and siloxydiamine amounting to from 1 to 10 mol %. The tetracarboxylic acid component, the maleimide compound and the diamine component are dissolved in a solvent which is consisting essentially of .gamma.-butyrolactone. The amount of the tetracarboxylic acid component is substantially equivalent to that of the diamine component. The amount of the maleimide compound is from 5 to 30 wt % of the total weight of the tetracarboxylic acid and the diamine component.