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:
Dec. 29, 1998
Filed:
Jun. 05, 1997
Keitarou Seto, Kyoto, JP;
Yoshiaki Echigo, Kyoto, JP;
Shoji Okamoto, Nara, JP;
Minoru Saitou, Kyoto, JP;
Unitika Ltd., Hyogo, JP;
Abstract
This invention provides a polyimide precursor solution having high concentration and low viscosity and a production process thereof, and polyimide coatings and films having excellent physical properties obtained therefrom and a production process thereof. Particularly, it relates to a polyimide precursor solution which contains a salt of a specific diamine with a specific tetracarboxylic acid, as its solute; to a process for the production of the polyimide precursor solution, which comprises allowing 1 mole of a specified diamine to react with 0.3 to 0.9 mole of a specific tetracarboxylic acid dianhydride, thereby obtaining a diamine, and subsequently adding 0.95 to 1.05 moles of a specified tetracarboxylic acid to 1 mole of the thus obtained diamine; to a polyimide coating or film obtained from the aforementioned polyimide precursor solution; and to a process for the production of the polyimide coating or film, which comprises coating the aforementioned polyimide precursor solution on a substrate and heating the coat to effect imidization.