| 摘要 |
PROBLEM TO BE SOLVED: To provide a resin sheet (metal foil with resin) capable of suppressing a peel strength between an insulating layer and a circuit under a high-temperature and high-humidity environment by HAST, even when a metal foil having a surface with low roughness is used.SOLUTION: A resin sheet for forming a circuit by a subtractive method or a modified semi-additive method contains a metal foil having first and second main surfaces, and a resin layer joined to the first main surface of the metal foil. An arithmetic average roughness (Ra) of the first main surface of the metal foil is 300 nm or less. A thickness of the resin layer is 8 μm to 400 μm. The resin layer contains one or more curing agents selected from the group consisting of (a) an epoxy resin, and (b) an active ester-based curing agent and a triazine structure-containing phenolic curing agent.SELECTED DRAWING: None |
