| 摘要 |
PROBLEM TO BE SOLVED: To provide a polyimide sheet in which a thermal expansion coefficient in a plane is small, anisotropy in the thickness direction is large, and break point distortion is extremely large. SOLUTION: The polyimide sheet is produced by laminating a plurality of polyimide films. When the plane direction of the polyimide sheet is an X-axis and a Y-axis, and the thickness direction of the sheet is a Z-axis, between a thermal expansion coefficientαin the X-axis direction and a thermal expansion coefficientβin the Y-axis direction, the relationship ofβ≥1.5αis established, and betweenαand a thermal expansion coefficientγin the Z-axis direction, the relationship ofγ≥10.0αis established. COPYRIGHT: (C)2011,JPO&INPIT |
