Patent ID: 6132865
Filing Date: 2000-10-17
Classification: B32B,C09J,H01L,Y10T

Abstract:
An adhesive tape for electronic parts which comprises a metal substrate and an adhesive layer A and an adhesive layer B laminated in order on at least a surface of said metal substrate, wherein said layer adhesive A comprises a polyimide consisting of 100-20% by mol of the repeating unit represented by the following formula (1a) and 0-80% by mol of the repeating unit represented by the following formula (1b), said adhesive layer B comprises a polyimide consisting of 100-40% by mol of the repeating unit represented by the following formula (1a) and 0-60% by mol of the repeating unit represented by the following formula (2), and the adhesive layer A and the adhesive layer B have each a different glass transition temperature: ##STR8## wherein Ar represents a divalent group selected from the following formulas containing aromatic rings: ##STR9## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 which may be identical or different represent each a hydrogen atom, an alkyl group having 1-4 carbon atoms or an alkoxy group having 1-4 carbon atoms, provided that R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are not hydrogen atoms at the same time: ##STR10## wherein R is an alkylene group having 1 to 10 carbon atoms or --CH.sub.2 OC.sub.6 H.sub.4 --, the methylene group of which attaches to Si, and n means an integer of 1 to 20.