| 摘要 |
PROBLEM TO BE SOLVED: To provide a multilayer printed wiring board in which a solder resist layer is prevented from being cracked.SOLUTION: A non-volatile component in a resin composition of the solder resist layer and a non-volatile component in a resin composition of a build-up layer are the same in 97 mass% or more. When the non-volatile component in the resin composition of the solder resist layer is 100 mass%, a content of silica is 40 to 85 mass%, a linear thermal expansion coefficient a(ppm) of the solder resist layer at 25 to 150°C and a linear thermal expansion coefficient b(ppm) of the build-up layer at 25 to 150°C satisfy 12≤a≤(b+5)≤30 and an elastic modulus of the solder resist layer at 23°C is 7 GPa or higher, such that the resin composition forming the solder resist layer and the resin composition forming the build-up layer are substantially similarly constituted.SELECTED DRAWING: None |
