Options for Printing on T-Shirts

I don’t know about you, but I’ve been living in t-shirts since the start of Covid. Even before the pandemic, my fiancee and I would look through the second-hand stores for t-shirts with pithy sayings about life. They would get our art therapy students talking.

But how are these printed? What are the options? Here’s a brief primer based on my research. If you’re interested, one of the best articles I found on the subject is available at: https://silverbobbin.com/types-of-printing-on-t-shirts/. Much of the following information has been abstracted from this article and then augmented with other research and my own experience over the past several decades.

Direct-to-Garment

Everything depends on the fabric you’re using. For cotton, your best option is inkjet. An inkjet print head travels down the shirt (which is immobilized on a shelf in the equipment).The good news is that you can print unlimited colors and incredible detail. You can even include photographs.

That said, the fabric usually has to be treated before this process and then again, afterwards, with heat and a wash in order to maximize the longevity of the printed image on the shirt. Direct to garment eventually degrades, more so with inkjet on cotton fabric than with dye sublimation.

If your shirt is polyester, you’re in luck. Using dye sublimation inks, you can print on a transfer sheet (usually, but not always, instead of printing directly on the garment). You then lay the transfer sheet on the t-shirt where you want it to print, and you apply heat from a heat press. The heat makes the solid inks become a gas that will migrate into the fibers of the polyester shirt. They actually become chemically bonded to the garment fibers and are therefore more resistant to degradation than inkjet printed on cotton fabrics. Further good news is that the colors are extremely bright. That said, both direct inkjet and dye sublimination work best on lighter fabrics (i.e., the color of the substrate either brightens or darkens the overprinted images).

Furthermore, with both inkjet printing on cotton and dye sublimination printing on polyester t-shirts, the feel of the fabric (called "the hand”) is soft, since the inks or dyes travel into the fibers of the t-shirt rather than sitting on the surface of the garment as a thick film.

The bad news is the cost of the equipment. Dye sublimation equipment is pricey. That said, you can often find a t-shirt-printing vendor with both inkjet and dye sublimation capabilities.

Screen Printing and Indirect Screen Printing with Plastisol Inks

Screen printing is one of the oldest methods for decorating fabric on the planet. Using a rubber squeegee, you force ink through a mesh screen on which you have applied a stencil. Your stencil blocks out non-image areas and keeps image areas open, so the ink can travel through the screen onto the t-shirt. With various chemicals you can even prepare photo halftones on the screens.

The good news is that the ink is very thick and vibrant. It soaks into the t-shirt, but it also forms a thick layer right on the surface of the garment. However, you have to print one color at a time and then clean it up and prepare a new screen with a new stencil. So this process is very time consuming, and therefore it lends itself to one-, two-, or three-color decoration (in contrast to the multi-colored options and full-color photographic imagery available with direct to garment inkjet or dye sublimation printing). If you’re printing a lot of shirts, screen printing is ideal, since you can proceed quickly with each ink color once you have set up the screen. That is, the longer the press run the better. (If you want one t-shirt, look to inkjet or dye sub.)

In terms of durability, screen printing lasts a long time. The inked images are very durable. And since no heat is involved in the process, you can use almost any fabric, including cotton, polyester, and nylon (i.e., unlike heat-based processes, you don’t have to worry about melting the fabric).

A variant on screen printing is using water-based screen printing inks (plastisol) to first print on a transfer sheet and then transfer the image to the t-shirt. (This is called indirect screen printing.) In this process, you would first have a professional print the transfer sheets from your digital files using plastisol inks, and then you would transfer the plastisol inks to the garments yourself using a heat press.

One thing to keep in mind is that you need a knowledgeable vendor to make the transfer sheets. If this is done incorrectly, the printed images will crack and peel off.

Vinyl Lettering and Iron-On Vinyl Images

At its simplest, the HTV (heat transfer vinyl) process involves cutting images from vinyl (professionally or using a Cricut appliance yourself) and then attaching the bonding side (with the adhesive coating) to the fabric with a heat press.

The bad news is that the art must usually be rather simple (like lettering attached to the fabric), but you also have the option of attaching a vinyl applique (perhaps a multi-colored, detailed inkjet print) to the fabric. These have been around for a long time. We used to call them "iron-ons.” They are incredibly durable (until they crack and start to peel off) because of their thickness. They do not seep into the fabric at all. They are a solid layer attached to the t-shirt. Unfortunately this means they do not provide the soft feel that direct-to-garment printed images have. Another benefit is that you can use various varieties of vinyl, including glitter, velvet, and metallic vinyl.

However, since you’re using high heat to attach the vinyl applique or lettering to the t-shirts, you need to consider the heat tolerance of the fabric. Cotton can take a lot of heat. Polyester can melt a little or a lot. And iron-on transfers are far more vibrant on light-colored fabric than on dark-colored fabric.

Unfortunately, over time, even lettering and images applied with a heat press will crack and peel.

Stencils

This is similar to screen printing. Your stencil is open in the image areas and closed in the non-image areas. You apply dye or ink over the stencil, and then you remove the stencil. It’s just like spray painting letters onto a storage trunk using a stencil and a can of spray paint. You can do this yourself, but creating multiple shirts can take a long, long time.

How to Choose a Method

1. Consider how many copies you will want to make. Direct to garment (inkjet or dye sublimation) equipment prints relatively slowly, albeit in high detail. Also, you will most likely want to find a professional t-shirt printer for your job. In contrast, screen printing is better for longer runs, but you may need to limit the colors you print.

2. Consider the fabric. A polyester t-shirt can be printed with a dye-sublimation press or with screen-printing equipment. Cotton t-shirts need inkjet- or screen-printing technology.

3. Closely related to the choice of fabric is the heat tolerance of the fabric. Cotton accepts high heat, but nylon does not. So printing processes using a heat press can be problematic.

4. Consider durability. Screen printing and heat transfer vinyl are very durable, whereas inkjet fades a bit with each wash. Remember that all t-shirt decoration will fade or crack and peel eventually.

5. Consider the feel of the printed product. Heat transfer vinyl feels like it is attached to the surface of the t-shirt (which it is). A dye-sublimated decoration on polyester feels soft, as does an inkjet image on a cotton t-shirt, because the inks seep into the t-shirt fabric.

Personally, I like screen printing best, because the garment is flexible, the inks are vibrant, and the images last a long time. However, for a short run I can’t justify the cost.

So discuss all of these options with various print vendors. And think about the length of the press run and the pros and cons of the options I have mentioned. Pretty much all of them are a trade-off.

[Steven Waxman is a printing consultant. He teaches corporations how to save money buying printing, brokers printing services, and teaches prepress techniques. Steven has been in the printing industry for thirty-three years working as a writer, editor, print buyer, photographer, graphic designer, art director, and production manager.]