bleed

In more detail

A blade never falls exactly where it should. The paper moves, the stack shifts, the knife wanders by a fraction of a millimetre — and a colour that stops precisely at the finished edge leaves a white sliver the moment it does.

So the sheet is drawn larger than the finished page and the colour is carried out past the cut, usually by three millimetres. Whatever the blade takes, it takes ink.

What it does on a real document

A file for a press therefore carries two rectangles rather than one: the sheet as it is printed, and the finished page inside it. Both are written into the document, so nobody has to measure the difference or ask what was meant.

The other half of the rule is inside the cut: nothing that has to be read may sit against the finished edge, because the same wandering blade can take a few tenths of a millimetre off the page as easily as leave them on.

Where it comes from, and why

The word is the printer's own: the ink bled off the edge of the sheet. It says what the trade has always done — print the colour too far on purpose, then cut the sheet down through it — and it is the only way anybody has found to end a colour exactly at the edge of a piece of paper.

See it on a finished document

A sheet prepared for the printing works A sheet as it goes to the press The rules behind this word, and the texts they are read from