I'm afraid I've never heard of such a thing. Printer page-break is exclusively from the world of print and web pages are, well, not.
If you yourself are trying to do it, then I might suggest using a word processor and then pasting screenshots into it.
If, however, you want to force a Client box to do this, it's going to be a real trick.
That said, here's a dippy idea that might do it:
If I wanted to force a page break, I'd reason that I'd want to force the browser to print my content as two separate documents, as paper control is pretty much nonexistent in the world of the web. So, I would appropriately divide my content up such that each "section" appeared in a different one of stacked frames. There would be no visible border, so it would all appear as a seamless page, but there would be three different frames there.
Now the tricky part. Can I, when the browser tries to print the page, tell it to print Frame_01, then print Frame_02, then print Frame_03. Sequentially?
That's what I would explore.
Cheers,
Edward "Cut a hole in the door. Hang a flap. Criminy, why didn't I think of this earlier?!" -- inventor of the cat door