| 摘要 |
PROBLEM TO BE SOLVED: To provide a new envelope structure which contributes to improvement of an opening rate of an envelope type direct mail.SOLUTION: An envelope is structured by sealing a two-folded cardboard. Perforations are formed along a vertical edge and horizontal edges on upper and lower sides of one surface of the cardboard. A cut part of the perforations includes a first cut part having a non-cut part alternately formed on a line to be separated, a second cut part continuously formed on a rear end of the first cut part in an opening direction, and a third cut part continuously formed with the second cut part. The first cut part and the second cut part form an obtuse angle, and the third cut part and the first cut part are formed in approximately parallel to each other. |
