Method of protecting polyimide materials during etching. RU patent 2447628.

FIELD: chemistry.

SUBSTANCE: method of protecting polyimide materials during etching involves a process for etching parts of the polyimide material with alkaline solutions. Before the etching process, the polyimide material is covered with a mixture of epoxy-urethane varnish with an oligoester acrylate additive, with the following ratio of components, wt %: epoxy-urethane varnish 93.7-95.2, oligoester acrylate 4.8-6.3. The part of the polyimide material which is not supposed to be etched is then protected with an insulating layer.

EFFECT: providing conditions for etching fully polymerised polyimide which ensure accuracy of the shape and dimensions of the etched areas.

3 ex

IPC classes for russian patent Method of protecting polyimide materials during etching. RU patent 2447628. (RU 2447628):

H05K3/28 - Applying non-metallic protective coatings

H01L21/311 -

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