To provide an envelope sheet formed into an envelope which effectively prevents information of an item enclosed from leaking due to a damage in a perforation, etc. by effectively preventing the perforation from being damaged unexpectedly.
The envelope sheet comprises a sheet with a particular width and can be formed into an envelope by folding the sheet in the longitudinal direction and bonding a predetermined part. The sheet comprises an envelope-forming strong-bonding part 10 continuously or intermittently formed on both end parts of superimposed faces in a folded condition and the perforation 15 formed on the inside of the part 10 for inducing separation of the part 10. A separable weak bonding part 11 is provided at the inside of the perforation 15 on both ends of the superimposed faces in the folded condition.
| JPH11147541A | 1999-06-02 | |||
| JPH03124889A | 1991-05-28 | |||
| JPH01145470A | 1989-06-07 | |||
| JPH0395766U | 1991-09-30 |
Takao Ito
Jiro Higuchi
Masataka Otani