What Is PET Film in DTF Printing? Why Film Quality Matters

Short answer: PET film in DTF printing is the clear polyester sheet that the color ink, white ink and adhesive powder are printed on. It carries the design from the printer to the heat press and is peeled away after pressing. DTF film is usually about 75 microns (0.075 mm) thick, has an ink-receiving coating on the print side and a release coating that lets the design let go of the film at the right moment.

This guide explains how DTF film is built, why film quality decides how a transfer prints, peels and washes, and how hot, cold and warm peel films differ. For the full printing process, see our guide on what DTF printing is. BeeDTF prints DTF transfers in San Jose, California, and ships them across the United States.

What layers does DTF PET film have?

DTF PET film has a polyester base with up to three functional coatings: a release layer, an ink-receiving layer and, on many films, an antistatic back coating. Each layer has one job.

Only the inked areas transfer to the garment. The film itself never touches the fabric fibers; it is a temporary carrier.

Why does PET film quality matter?

Film quality matters because the film controls three things the customer sees: how sharp the print is, how cleanly it peels and how evenly the adhesive bonds. In one independent test of 23 DTF films, only 3 passed every print, peel and wash check.

• Sharpness: a weak ink-receiving coating lets ink spread, so fine lines and small text lose detail.
• Clean powder: a coating that is too sticky holds loose powder in empty areas, which leaves a hazy outline on the shirt.
• Heat stability: a thin or low-grade base warps at curing temperatures and causes uneven adhesive.
• Peel: an inconsistent release layer makes the film stick in some spots and lift early in others.

A print can look perfect on the film and still fail on the shirt if the release or base layer is weak. That is why print shops test film on real garments, not only on screen.

Which peel type does your film use?

The peel type tells you when to remove the film after pressing: immediately (hot), after full cooling (cold) or after a few seconds (warm). The release coating decides the peel type, so the same printer can produce all three with different films.

BeeDTF prints on hot-peel film: press at 275°F for 7 seconds with medium pressure, peel hot, then finish-press for 5 seconds. Peeling a cold-peel film while it is hot can lift the print, so always follow the peel type your supplier states. Full press steps are in our DTF heat press settings guide.

Single-sided vs double-sided matte film

Single-sided film has a matte coating only on the print side; double-sided film is matte on both sides. Both print the same way, on the matte coated side.

• Single-sided: one matte side, one glossy side. The glossy back makes it easy to see which side to print on.
• Double-sided matte: grips printer rollers better, slides less in feeders and shows fingerprints less. You must check the label or test which side is coated.

Printing on the wrong side is a common beginner mistake. The ink sits on the uncoated surface, beads up and smears.

DTF film sizes: sheets and rolls

DTF film comes in cut sheets for desktop printers and rolls for roll-fed printers. The format follows the printer, not the design.

Gang sheets at BeeDTF are 22″ wide and any length you need, so many designs share one run of film.

How to store and handle DTF film

Store DTF film sealed, flat and dry, away from direct sunlight and heat. The coatings absorb moisture from the air, and damp film prints poorly and attracts powder.

• Keep it sealed: reseal opened packs or rolls in their bag.
• Keep it flat: store sheets flat and rolls on their ends or hung, so they do not dent or curl.
• Control humidity: 45–60% room humidity suits both film and DTF ink.
• Handle by the edges: skin oil on the coated side repels ink and holds powder.
• Let it adjust: film moved from a cold or hot space should sit in the print room before use.

The same rules apply to finished, unpressed transfers: a sealed bag, a cool and dry place and no weight on top.

How to tell good film from bad film

Good DTF film prints sharp, stays flat in the dryer and peels clean with no residue. Bad film shows its problems in the first test print.

A full checklist for judging finished transfers, including the white layer and the adhesive, is in our DTF transfer buyer's guide.

Does film quality matter when you order transfers?

Yes, but when you order ready-to-press transfers, choosing and testing the film is the print shop's job. What you see is the result: a sharp print, a clean peel and a transfer that survives washing.

When you receive transfers, check three things: empty film areas are clean, the back is evenly white and matte, and the film peels away hot without lifting the print. To order many designs on one 22″ sheet at $0.34–$0.50 per inch, use the DTF gang sheet builder.

Frequently asked questions about DTF PET film

What does PET stand for in DTF film?

PET stands for polyethylene terephthalate, a clear, heat-stable polyester. The same material family is used in food packaging and polyester fabric.

How thick is DTF film?

Most DTF film is about 75 microns (0.075 mm) thick, with a common range of 75–100 microns. Thicker film stays flatter under heat but costs more.

Which side of DTF film do you print on?

You print on the matte coated side. On single-sided film, the glossy side faces down; on double-sided matte film, check the label or test both sides.

Can you reuse DTF film?

No. The release and ink-receiving coatings are used up in one print and press, so DTF film is single-use.

Is DTF film the same as screen printing film?

No. Screen printing film is used to expose screens and never touches the garment. DTF film carries the actual print to the garment.

Can I use hot-peel and cold-peel film the same way?

No. Hot-peel film is peeled right after pressing; cold-peel film must cool completely first. Peeling at the wrong time can lift or damage the print.

Is DTF film recyclable?

PET is recyclable in general, but used DTF film carries ink and coating residue, so most local programs do not accept it. Check with your local recycling service.