USE OF POLYMIDES PREPARED FROM POLYAMIDE ACIDS

Described are polyamic acids, at least 50 mole-% of which are comprised of recurrent units corresponding to the general formula I: (I) wherein, R1 is a mono-, di-, tri- or tetranuclear aromatic group and X is O, S, CO, SO2 or CR2R3, each one of R2 and R3 being H or CH3. A polyamic acid of the presen...

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Main Author HUPFER, BERND
Format Patent
LanguageEnglish
German
Published 28.11.1990
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Summary:Described are polyamic acids, at least 50 mole-% of which are comprised of recurrent units corresponding to the general formula I: (I) wherein, R1 is a mono-, di-, tri- or tetranuclear aromatic group and X is O, S, CO, SO2 or CR2R3, each one of R2 and R3 being H or CH3. A polyamic acid of the present invention, in the form of a solution, is applied to a substrate, for example, a semiconductor device, to form a protective layer thereon, and is converted into polyimide by heating. As against comparable compounds known in the art, the polyamic acids of the present invention are distinguished by a lower inherent viscosity at an unchanged molecular weight and, consequently, by an improved processability at an equally good thermal stability.
Bibliography:Application Number: EP19870106017