| 摘要 |
An envelope is formed from a single sheet of paper, which is of a standard size. The paper is folded along opposing edges and then folded along a mid-section. Content material may be placed in the envelope or printed information can be printed on desired surfaces of the envelope. The paper may also be folded so that a fold-over flap is formed. The edges are attached through a sealing mechanism such as knurling or crimping. |
