| 摘要 |
PROBLEM TO BE SOLVED: To provide a substrate that exhibits a preferable whiteness degree even in a high-temperature environment.SOLUTION: The substrate includes at least a resin layer. The resin layer contains a resin essentially comprising a polyimide resin. The substrate exhibits a Hunter brightness degree of 84% or more of the resin layer after heated at 260°C for 60 minutes. It is preferable that: the substrate exhibits a retention rate of 93% or more in the Hunter brightness degree of the resin layer after heated at 260°C for 60 minutes; the resin layer side of the substrate exhibits a total ray reflectance of 75% or more after heated at 260°C for 60 minutes; and the retention rate of the total ray reflectance at the resin layer side is 94% or more after heated at 260°C for 60 minutes. |
