How to Achieve Bright and Vibrant Direct-to-Garment (DTG) Prints on Dark Colored Shirts:
Tips & Tricks from DTG Experts
One of the most common challenges for direct to garment (DTG) printers is achieving a bright, brilliant print on dark or black garments. By nature, the CMYK water-based DTG inks are translucent. When printed on a dark background they lack any vibrancy and provide a very washout look. There are several keys to making DTG color look bright.
Apply Pretreatment Solution Correctly and Consistently
When printing DTG on dark colored shirts, you must pretreat each garment. A common question is, what counts as a “dark” shirt? An easy rule to follow is, if you are using white ink you must pretreat. You can also pretreat white shirts, but it is not necessary. If you do choose to pretreat a white shirt, it will boost the color and help improve wash fastness.
If the shirt looks dull or faded when printed, or starts fading after only a couple of washes, chances are that the problem is rooted in the pretreatment process. Pretreatment solution must be applied evenly and consistently, and must be completely dry, or cured, before the DTG ink is printed over it. Too little pretreatment liquid will make the image look dull, hazy, or faded. Too much pretreatment will make the fabric stiff and can actually prevent the ink from ever adhering to the fabric at all, instead only resting on the surface of the pretreat solution saturating the shirt. This would cause the image to wash out completely.
Avoid applying too little, too much, or uneven application by using a pretreat sprayer. You can measure the exact amount of solution that has been applied by weighing the garment and keeping a record of the amount that works best for you. Thirty (30) grams of solution per shirt is a good benchmark.
Keep Your DTG Printer in the Proper Environment by Monitoring Humidity and Temperature
DTG ink is water-based, so humidity and temperature affects its printing ability. With humidity too low, the DTG ink has trouble passing through the print heads correctly. The ideal humidity for a DTG printing environment is 40 up to 70%. If your DTG machines senses it is in an environment that has a humidity level outside the range, it will increase its automated cleaning cycles to protect itself. While this might help in the short term, it increases your operating and maintenance costs. For more information on maintaining your direct to garment printer's environment, read our blog Getting Better DTG Printers through Proper Environmental and Humidity Levels for a DTG Printer
Temperature also affects the behavior and fluid dynamics of the ink. Inks that are too cold will be very slow going through the machine. If it’s too hot, the ink can start to dry in the print head, building up and blocking ink from passing through. A comfortable room temperature (72 degrees F) is generally the ideal temperature.
Select the Right T-shirts and Garments for DTG Printing
It’s important to select a good quality t-shirt, hoodie or other garment to print on. Tightly woven, smooth 100% ring spun cotton is the best substrate choice for DTG printing. Cheaper, low quality shirts use thicker yarn and cheaper dyes that tend to bleed or migrate into the printed area when cured. This is one of the common causes for dull, muted prints.
You will have to do some trial and error to find the shirts or brands that work best for you. Ask others in the industry what brands and styles they prefer and which they steer clear of. Any time you switch to a different brand or type of shirt, it’s important to run tests to lock in the ideal pretreat settings for that particular garment.
Curing and Drying Your Finished DTG Print Properly
Does your image look great when you first print the shirt, but dulls as it dries? If you’re using a heat press to cure the print, the pressure might be the problem. It can mash down the ink into the woven fabric of your tee shirt instead of allowing it to stay and adhere to the surface. To combat this, adjust your heat press technique or change your method of curing your prints altogether with a conveyor DTG dryer or Digi-Dry Box.
If using a heat press, briefly hover the heat element over the image to produce a quick surface cure, but avoid pressing down and smashing the ink into/below the surface of the fabric. If you have the space and resources, we recommend using a heat press just to press down the fibers in the fabric before printing, and then using a conveyor-style dryer to cure the printed image itself. Learn more about how different curing methods affect the quality of your DTG print in our blog Choosing the Right Method for Drying Your DTG Prints.
The ability to produce bright, high quality prints on dark garments will make you highly competitive in the DTG industry. Though it will still require some trial and error in your own shop using your own equipment, implementing these tips will put you ahead of the crowd.