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:
May. 20, 1986
Filed:
Jun. 20, 1984
Hellmut Ahne, Rottenbach, DE;
Wolfgang Kleeberg, Erlangen, DE;
Roland Rubner, Rottenbach, DE;
Hans Kruger, Munich, DE;
Siemens Aktiengesellschaft, Berlin and Munich, DE;
Abstract
The invention relates to a method for the preparation of thin polyimide layers by applying a solution of a polyimide prepolymer to a substrate, and subsequently annealing, and has as its object the provision of a method of this type in such a way that the preparation of layers with layer thicknesses of .ltoreq.0.2 .mu.m is made possible which layers have a homogeneous character and exhibit good adhesion. For this purpose, the invention provides that film-forming prepolymers of highly heat-resistant polyimides are used which prepolymers give off a high percentage of volatile products in annealing. The method according to the invention is particularly suitable for the production of orientation layers for liquid-crystal displays.