| abstract |
An object of the present invention is to provide an adhesive composition for a printed wiring board, the adhesive composition having a good heat resistance. Another object of the present invention is to provide a coverlay for a printed wiring board, a copper-clad laminate, and a printed wiring board, all of which use the adhesive composition for a printed wiring board. The present invention provides an adhesive composition for a printed wiring board, the adhesive composition containing a siloxane-modified polyimide that includes structural units represented by formulae (1) and (2) below, an epoxy resin, and an inorganic filler. The siloxane-modified polyimide has a weight-average molecular weight (Mw) of 25,000 or more and 150,000 or less. A content of the inorganic filler is 10 parts by mass or more and 100 parts by mass or less relative to 100 parts by mass of the siloxane-modified polyimide. In formulae (1) and (2), Ar represents a tetravalent aromatic tetracarboxylic acid residue, m is 0.35 or more and 0.75 or less, and n is 0.25 or more and 0.65 or less. R 1 in formula (1) represents a divalent diamine siloxane residue, and R 2 in formula (2) represents a divalent aromatic diamine residue. |