Patent ID: 6395391
Filing Date: 2002-05-28
Classification: B32B,C09J,H01L,Y10T

Abstract:
An adhesive tape for electronic parts which comprises a metal substrate and an adhesive layer A, an adhesive layer B and an adhesive layer C laminated in order on at least a surface of said metal substrate, wherein said adhesive layer 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), said adhesive C comprises a polyimide consisting of 90-40% by mol of the repeating unit represented by the following formula (3a) and 10-60% by mol of the repeating unit represented by the following formula (3b), and the adhesive layer A, the adhesive layer B and the adhesive layer C have each a different glass transition temperature: wherein Ar represents a divalent group selected from the following formulas containing aromatic rings: wherein R1, R2, R3 and R4 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 R1, R2, R3 and R4 are not hydrogen atoms at the same time: wherein R is an alkylene group having 1 to 10 carbon atoms or â€”CH2OC6H4â€”, the methylene group of which attaches to Si, and n means an integer of 1 to 20; wherein X is a tetravalent aromatic group selected from the group consisting of 3,3â€²,4,4â€²-diphenyl sulfone structure, 3,3â€²,4,4â€²-biphenyl structure and 2,3â€²,3,4â€²-biphenyl structure, and Ar and R represent each the same meaning as described above.