Many emails received from Japanese companies contain characters-based dingbat-style ornament like this:
■□■□■□────────────────────────────
blablablablablablablabla
────────────────────────────■□■□■□
■blabla
| bla:blablabla
| bla:blabla
■┓ bla ┏■
┗┛━━━━━━━━━━┗┛
...
It seems to be a particular case of Shift_JIS art (which I don't know how to say in Japanese either, by the way).
What do you call this type of email decoration in Japanese?