| abstract |
[PROBLEMS] To provide excellent flow characteristics at the time of lamination, excellent embedding in an inner layer circuit, adhesion to a circuit board, smoothness of an outer layer circuit after lamination, and an extremely thin plate thickness using almost no glass cloth. Furthermore, the present invention provides an epoxy resin composition for multilayer printed wiring boards, which is further heat resistant and storage stable. A phosphorus-containing flame-retardant resin composition having a weight average molecular weight range of 10,000 to 200,000, a phosphorus content of 0.5% to 10% by weight, and an acid value of 10 mgKOH / g to 200 mgKOH / g. object. [Selection figure] None |