Canon iR6570 Manual page 257

I If You Want to Print on the Interleaf Sheets:
The [Print] setting outputs a printed transparency and a printed interleaf sheet alternately.
1
On the Special Features screen, press [Transparency Interleaving].
2
Load transparencies into the stack bypass.
Originals
Printed Interleaf Sheets
Copies
Transparencies
Transparency Interleaving
4
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