| 摘要 |
PROBLEM TO BE SOLVED: To suppress strain of a composite sheet even heating by microwave irradiation is performed.SOLUTION: A blank sheet 20A comprises: a paper base material sheet 30A; a heat generation body sheet 4 for generating heat by microwave irradiation; and an adhesive joint 5 for sticking the sheets each other. The adhesive joint 5 comprises: paper grain direction adhesive joints 5x1, 5x2 having a length over substantially the entire width of the heat generation body sheet 4 and extending in the paper grain direction P; and a plurality of linear paper grain right angle direction adhesive joints 5y1, 5m, 5y2 extending in the paper grain right angle direction Q between the paper grain direction adhesive joints 5x1, 5x2 and arranged in the paper grain direction P in a separated state. The paper grain right angle direction adhesive joint 5m is disposed on the center of an area sandwiched by the paper grain direction adhesive joints 5x1, 5x2 and the total length per row of the paper grain right angle direction adhesive joints is 25% or more and less than 100% of the interval between the paper grain direction adhesive joints 5x1, 5x2. |
