Dieline PDF (Print-Ready)

The dieline PDF is the file printers, trade shops and packaging designers ask for when they say "send us the dieline": the cut and crease lines on spot colours of their own, overprinting, so the artwork can be placed on its own layers under them, with the bleed and safe-area guides and the finished size set in the file. Save one with File › Export › Export…, choosing Dieline PDF (print-ready); the options follow. The page worked on is written.

What it writes

The cut lines on a spot colour named Dieline (or the name you give: CutContour for print-and-cut RIPs such as Roland VersaWorks, Onyx, Caldera and SAi Flexi, Thru-cut, or what your printer asks for), shown 100% magenta.
The creases on a spot colour named Crease, shown 100% cyan, dashed (switch off Folds dashed for solid lines). Reverse creases are a spot colour of their own, named after their layer, unless Reverse creases on the crease spot is on. The other dieline layers (Perforation, Partial Cut, Cut Crease, Tape …) are spot colours named after their layers, in their layers' print colours.
Overprint on the dieline and guides, so they knock nothing out of the artwork under them and can be left off the printing plates. All of them are drawn at the Line width you choose (0.5 pt unless you change it), whatever the elements' own line widths.
The bleed guide, the Bleed distance outside each blank's cut outline (3 mm or 1/8 in unless you change it), on a spot colour named Bleed; and the safe-area guide, the Safe area distance inside each panel, on a spot colour named Safe area. Give 0 to leave either out. They are worked out afresh from the dieline, as Bleed and Safe Zone works them out; lines already drawn on the Bleed and Safe zone layers are left out then, or written on the guides' spot colours when both are 0.
Varnish-free areas, when you switch on Varnish-free areas: a filled area over each glued place, on a spot colour of its own (Varnish free unless you name it), for the printer's varnish plate. See Varnish-free areas.
Layers: every layer is a PDF layer (optional content) that Acrobat and Illustrator can show, hide or lock: the artwork's layers at the bottom, then the guides, then the dieline layers on top.
The artwork: the drawing's other layers (text, pictures, fills) in their print colours under the dieline. Switch off Artwork for a dieline alone.
Dimensions and other layers that aren't plotted: on layers that don't print (seen on screen, not printed), left out, or printed, as Dimensions says.
The page's trim box is the extent of the cut lines (the finished size) and its bleed box the trim with the bleed round it, as prepress programs and imposition read them; the page itself is the bleed with the Margin round it.

A drawing with no closed cut outline gets no guides and no trim box, and the messages say so.

Varnish-free areas

Glue doesn't hold on varnish or a heavy ink film, so printers keep them off where a carton is glued. With Varnish-free areas on, the file has a filled area over each glued place, on its own spot colour and its own layer, overprinting, under the guides and dieline:

Glue drawn on the Tape (glue) layer: a closed outline is the area as drawn; a glue line is a band 6 mm wide along it.
Side-seam glue flaps (the manufacturer's joint), found in the dieline when Find side-seam glue flaps is on: the narrow flap at the end of a row of walls, folded on to the wall at the other end. Its whole printed face is glued. Tuck flaps on lids and dust flaps aren't glue flaps and are left alone. A flap with glue drawn on it is left to the glue drawn.

Each area reaches past the glue by Reaches beyond the glue by (2 mm unless you change it), so the plate still covers the glue when the print is slightly out of register. Areas that meet are joined. Name the spot colour as the printer asks (Varnish free, No varnish, Glue area …): the area separates onto a plate of its own, which the printer uses to knock the varnish (and, if they choose, the ink) out. A drawing with nothing glued gets no area, and the messages say so.

Using it

Send it to the printer or designer: they place the artwork on its own layer under the dieline, run it out to the bleed guide, and keep text inside the safe area. The Dieline and Crease spot colours are for the die and the proof: they separate onto plates of their own, which the printer leaves out. For print-and-cut, export with the cut spot named CutContour (the Print and cut (PDF, CutContour) machine profile does): the RIP prints the artwork and sends the CutContour path to the cutter.

The Printer's dieline (PDF) and Print and cut (PDF, CutContour) machine profiles export it in one click with the usual settings. The SaaS API writes it too (POST /export/dielinepdf).

With Carry the design inside (on unless you switch it off) the PDF carries the drawing, so the file that comes back from the designer opens again as the design. With Update it each time the drawing is saved it is written again whenever you save the drawing, for artwork that has it placed as a link. See Working with Illustrator and CorelDRAW.

Standards

The file is PDF 1.4 as described in ISO 32000-1: spot colours are Separation colour spaces with CMYK alternates (§8.6.6.4), overprint is set in the graphics state (§8.6.7), layers are optional content groups (§8.11), and the trim and bleed boxes are the page boundaries of §14.11.2. It sets the boxes PDF/X asks for, but is not a PDF/X file (it has no output intent): a prepress program converts it if the printer needs PDF/X.