| 摘要 |
PROBLEM TO BE SOLVED: To simultaneously satisfy the bending property and the strength of a sheet by a method wherein a bending part is constituted of a large number of recessed parts which are formed on a sheet body, and the remaining parts between them, and border lines between the recessed part and the remaining part is tilted at an acute angle to the bending part forming direction, and at the same time, to the same side as the border lines being confronted across a remaining part. SOLUTION: A plurality of recessed parts 14 are provided on a sheet body 10, and a remaining part 16 of a parallelogram when being seen from the top is remained between the recessed parts 14, and thus, a bending part 12 is constituted. The recessed part 14 is formed into a V-shape when being seen from a bending part forming direction Y, and also is formed into the parallelogram when being seen from the top, and a plurality of border lines 18 are formed between the recessed part 14 and the remaining part 16. Then, when the sheet body 10 is bent to the face surface side on which the bending part 12 is formed in the bending direction X, the remaining part 16 is placed under a twisted state, and can be easily bent, and also, the strength of the sheet itself can be kept. Also, when the sheet body 10 is bent to the rear surface side, the border line 18 on the remaining part 16 tilts, and the remaining part 16 can be prevented from being damaged. In addition, the remaining part 16 is placed under a twisted state, and can be easily bent. |
