Discuss the various aspects of direct to garment printing. DTG printers include Brother, T-Jet, Flexi-Jet, DTG Kiosk, Kornit, Mimaki, Tex-Jet and others! Discuss and learn about this up and coming printing technology.
I'm trying to print with my T-Jet 2 on a Red Kap mechanics work shirt that is 65% poly and 35% cotton.
I'm having a problem with the ink soaking through the shirt even after heavy pretreatment.
Does anyone have a technique to keep the ink on top. It seems to look okay until I heat press it.
Thanks,
Andy
Have you tried flashing it by hovering the heat press over the shirt for 30 seconds before pressing? Make sure your press is set to the lightest pressure.
Has anyone done any more testing with poly/cotton? We are testing prints on black 80% polyester/20% cotton (American Apparel), using FastInks, and are having a similar problem of white ink losing its visual punch *after* heat pressing. We are using standard dark shirt pre-treatment.
We have tried various modes of pressing, such as repeated 20 seconds on/20seconds off, at about 330F, using siliconized parchment, but the white becomes quite weak and you can see what appears to be a shadow of white ink on the parchment afterward (although that may simply be the parchment itself becoming smoother where it comes in contact with the ink).
We will try the "flash drying" technique and very light pressure, as suggested by Mistewoods, but any other hints would be very much appreciated.
Here is the process we came up with. It is time consuming but if you are selling the product for enough it is worth it.
We did this on 65% polyester/35% cotton Mechanics work shirts. We had to use a Black colored shirt to keep the pretreatment from staining.
1.) Heavily Spray Pretreatment on print area.
2.) Press for standard pretreatment time. 8 - 12 seconds.
3.) Hang dry shirt for a few hours or overnight. (With our shirts if they were damp at all the print didn't maintain crisp lines)
3.) Print Design. In between each pass briefly pause the printer and lightly blow dry. (This wasn't always neccessary but it keeps the ink from pooling.)
4.) Hover heat press over print area for 4 -5 minutes without touching shirt.
5.) Hang Dry overnight
6.) Press the design for the regular time
This may seem like alot of work but we were doing them in batches of 10 and since we were getting $40 for a shirt we had $12 in, it seemed worth it.
Thanks *very* much for the info, and we will try your technique asap. We are printing the poly/cotton shirts in batches of about 20, so the process should work for us as well (although we're not charging as much for them ... yet).
This may seem like alot of work but we were doing them in batches of 10 and since we were getting $40 for a shirt we had $12 in, it seemed worth it.
That is great information. The key is understanding how much time / effort goes into making the product and make sure that you are rewarded properly for this effort.
Hopefully when the new Dupont ink will be released soon and it will adhere better to polyester fabric without pretreatment. You will still need the pretreatment for white ink, but just CMYK printing will be much easier.
We tried most of your technique and have noticed some improvement. By briefly using an air dryer after each pass we can see that the white ink on black keeps its strong punch. It's one underbase and two color layers, but a lot of the image contains white.
We then did the 4-minute "flash" dry procedure so that the ink takes on a slightly sticky surface and seems to still adhere to the polyester fibers quite well.
Because we're using a SwingMan heat press it's easy to get a uniform gap over the entire shirt surface (a bit more than an inch).
For the final drying we use a 330F temperature and almost no pressure at all, just enough to ensure the heat contacts all of the fabric surface. Most polyester fabrics can withstand as much as 390F so this should not be a problem. The lack of pressure may or may not affect the washability.
Without going thru an overnight dry, there is a loss of white brilliance after a half-time(120 sec) press, and a bit more after a cooling period followed by second 120-sec press. Maybe the overnight dry is required in order to get the white to stay brilliant. Is that what you found?
We found that without the overnight drying it seemed to Push the ink through the fabric.
We also found that if you do the overnight dry and don't press it, the ink peels off in the first wash. To answer question, we found the overnight dry was necessary otherwise we got the same muted results.
I would definately suggest doing wash tests once you figure out what makes it look the best.
Printing on 65% poly 35% cotton 
