What is something you know now about direct to film you wish you knew when you got started? It’s not that it can apply to any fabric imaginable. Not that it was going to be the next big thing in printing. It would actually be the only real problem with DTF and the simple way to resolve this. If you print direct to film on your direct to garment printer OR run any sort of DTF sheet printing (without the roll to roll system) stick around for this key survival tip for the mistake you’re probably making.

Like many direct to film users, I learned the process printing sheets at a time, one by one and learning the steps of powdering and drying all by hand. While this can technically work there is one thing we need to be mindful of with direct to film sheet printing: PINHOLES. Have you ever experienced bubbling, cracking or peeling in your DTF prints? To have to deal with such a disaster at that point after getting a good print, taking the time to powder and dry the film can feel terrible. What are we to do at that point? Start all over on that transfer AGAIN? And that’s assuming we catch - what would be worse is for that slip past quality control and end up in a customer’s hands thus tarnishing the credibility of your work and craft. The good thing is there is a quick and simple way to prevent this from happening, everytime.

The pinhole issue we are describing won’t happen on every print. In fact, there are a few key instances where this can potentially be a problem for a direct to film printer. Namely:

But WHY is this happening? If you consider how a roll to roll direct to film system works, the image is printed onto the film (wet) and passing an arc heating plate. After enough prints are run through, the first semi wet ink is passed through a powder station before going into the conveyor dryer portion of the system before curing and then finally rolled back up on a take up reel. Depending on the speed of the machine, that first initial print can take a couple minutes before it actually sees powder. When printing individual sheets at a time there is no pause and the first instinct after the sheet comes out is to continue production: powder, dry as normal with no waiting.

In the roll to roll system, the wet DTF prints have time and a little temperature before actually seeing the powder to coagulate to the proper level to still receive and hold powder before drying. If you are to powder and dry the sheet immediately the ink is considerably more wet. The fix is not to wait minutes before powdering and drying, that would be a waste of time. The quickest and easiest way to prevent pinholes before happening is with a curing oven: after the DTF sheet is printed, before powdering, simply place the wet film into the conveyor dryer and the recommended heat for 5 seconds then apply the powder and cure as normal. This sort of ‘flash dry’ will coagulate the ink to the appropriate level allowing the powder to still bond and cure as intended.

Because the ink is water based part of the design may try to evaporate in the oven once powder. Because the powder has already been applied there is no where for the evaporation to turn into a gas so the water boils and bursts creating pinholes. We have tested flash curing with the heat press and while this can also be effective some testing would be required depending on this style of drying the powder. In short, a DTF curing oven will be your best bet.