| 摘要 |
A fdd line (12) across the approximating middle of the sheet divides the envelope part (10 to 13) from the letter part (7, 12, 14, 15). At each corner of the envelope part, a hole (A, B, C, D) is punched and material is removed from the two long edges (3, 4) leaving a narrow strip (11, 13) between the pairs of holes (A, B and C, D) for application of adhesive. The operations of printing, perforating, adhesive application, cutting and folding are carried out in a given sequence by automatically operated apparatus. The letter portion is folded over, then the envelope portion is folded around it, the adhesive coated tabs (13, 16, 6) are bent over and secured around the edges. |
