The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 21, 1999
Filed:
Oct. 12, 1993
Jin-O Choi, Amherst, NY (US);
Occidental Chemical Corporation, Niagara Falls, NY (US);
Abstract
Disclosed is a method of forming a pattern on a substrate. A first solution is formed of an organic solvent and monomers of diamine and dianhydride. The monomers are polymerized to form a polyamic acid soluble in the organic solvent. About 20 to about 95% of the amic acid groups in the polyamic acid are imidized to form a partially imidized polyamic acid. A more concentrated solution of the partially imidized polyamic acid is formed. This can be accomplished by precipitating the partially imidized polyamic acid from the first solution and dissolving it in a second organic solvent to form a second solution. The second solution is applied to the substrate and the solvent is evaporated to form a coating of the partially imidized polyamic acid on the substrate. A portion of the coating is removed to form a pattern on the substrate and the remaining partially imidized polyamic acid is fully imidized on the substrate.