How to Choose the Best Process

Rick Roth is president of Pawtucket, R.I.-based Mirror Image. In recent years, his business has taken home numerous Golden Image awards in various categories, as well as top honors in the industry media's various printing competitions.

There has always been debate about what to do with a full-color image. If this was 1976 and we were talking about a full-color photo of Farrah Fawcett, then the answer would be easy—make a transfer and iron it on to a shirt and don’t worry about it cracking and peeling off. Well, it’s 30 years later and there are more options and improved methods… but sometimes just as much confusion as to what to do. Let’s examine the possible decoration techniques and some guidance on how to decide to get the “best” results.

Heat transfers

In the case of heat transfers, an image is put on to a carrier sheet which can then be applied (transferred, hence the name) to a garment with a heat transfer press. In small quantities, the transfer is usually created on special paper with special inks in a color printer. The advantages are fast turnaround, good color reproduction and relatively low cost for small quantities. Samples can also be produced quickly and inexpensively. 

The disadvantage of transfers is primarily that it is a transfer. The rest of the world has accepted and used transfers, but in the U.S. that cracked and peeling Farrah Fawcett or Dukes of Hazzard transfer gave them a bad image, one that transfer-paper manufacturers are doing much to debunk. 

The best opportunity to use transfers is to produce full-color shirts every time someone orders one. You can have a pile of transfers of various designs and just grab a blank shirt as you need one. The same goes for the store on the boardwalk in Atlantic City—you can store a lot of designs and you only need a few shirts in a small space.

A subset of this method, cad-cut digital transfers are digitally created and contour cut around the images. On full color images, they have most of the limitations of printed transfers but work better on dark garments and are more vibrant. These are very dependent on size, and bigger images cost much more. Besides costing less, small images can hold very minute details. The transfers are becoming increasingly sophisticated and, by utilizing different carrier sheets, can print over mesh, be more “breathable” and work on stretchy fabrics. However, it remains a three-step process of printing, cutting and transfer application and will be inherently slower and more expensive for longer runs. They are an excellent method for putting full-color images in difficult areas for printing (we recently put a tiny image on the back of a razor-back tank, for example), for short runs, and for small, detailed color images. 

Direct-to-garment technology involves an inkjet printing directly on to a shirt. This technology is coming on strong.  Anyone that has been to a trade show recently can attest to this, as there are countless purveyors of these machines. Just like your Epson inkjet printer at home prints on to a piece of paper, this technology does the same on to a garment, or in some cases, hard substrate. Actually, in most cases, the printers operate with Epson print heads running textile-friendly inks. Some of the medium to higher-priced models use print heads of their own manufacture. 

Digital prints can have very good color reproduction. You can run small quantities relatively inexpensively and sample very inexpensively. Dark garments print slowly in all cases, but at least a few machines are now able to do it even though the inks are relatively costly. They also aren’t as “push button” easy as they appear to be and for best results, either the input (manipulation of the image in Photoshop or other programs) or output (changing the machine settings for saturation, etc.) must be adjusted. Direct printing achieves full-color prints easily and is a great option for mail order and printing on demand, particularly on white and natural shirts. The color saturation on the graphic elements added to a full color image are still not as strong as screen printing inks and in general, the prints are not as “punchy” or vibrant as good screen-printed images. However, digital seems to improve every day and becomes a reasonable alternative to screen printing. On larger print runs, digital is still too slow and expensive, but the gap is closing. There are also experiments with combinations of digital and screen printing, so you can screen print type and logos along with the full-color image, but again these are not quite ready for primetime yet, in my opinion.

CMYK process screen print

Also know as full-color process, traditional process or simply process printing, most call this four-color process. The process involves screen printing a color separation—that is, the image broken into four separate halftone (tiny dots) screen prints—of an image. There is a print each of cyan (blue), red (magenta), yellow, and black. When your eyes see various combinations of these colored dots close together, your brain reads it as a color that is a combination color. For example, combine a few blue dots with some red ones and you see purple. With offset printing and many other print methods (magazines, newspapers, paper in general) the halftone dots are so small that you cannot see the individual dots without magnification. Screen printed process printing is a far more crude enterprise and the dots are relatively large. Some printers add a resist white and/or a highlight white, and they can add a color or two (expanded gamut) or have weird-shaped dots, or even use different dot patterns… but the concept is all about the same. For all but a few extremely talented and well-organized print shops, process printing is an ordeal. 

To print four-color process on dark shirts, there has to be a full white print under the process print, which usually constricts the breathability of a garment. It’s very inky and only a few printers do it well. The advantages are that a good color separator can relatively quickly separate the image. Also, the advantage is that you can print any image with only as few as four screens. This is also the disadvantage as it is impossible or at least very difficult to recreate all the colors you might want with only the four process colors. Tertiary colors like browns, grays and flesh tones can be particularly difficult to reproduce as even a little issue with the ink, color separations, screens or printing pressure can result in greenish or pink, or colors can even start varying shirt to shirt if your press isn’t perfectly in tune. 

CMYK printing is the solution if you have a small press. It also works well on pastel images, particularly if there are many different tones in the image or many subtle details. You also can add a screen for type or logos and not print the part of the graphic with a halftone to make up for the deficiency.

Simulated process 

Simulated process involves screen printing halftones to reproduce full color images, only using colors that are chosen by the color separator rather than the CMYK screens of traditional process. The color separations are more expensive and time consuming than CMYK separations, and it takes an experienced separator to get great results. There are usually more screens, sometimes up to 11 or 12, and nearly as many inks to be mixed. This cost to the screen printer has to be passed on to the customer. Also, if you are not quick and good at mixing inks, this process is not likely a viable method. It typically requires a large press, usually with at least 10 print stations.

For large print runs, separations and set-up time get amortized over more shirts and the price is as low as any other method. In fact, for well-organized shops, it is faster to set up the additional screens involved with simulated process than it would be to try and get the CMYK prints to have the right color balance. Color shifts in simulated process are subtle and usually unnoticeable. 

The benefits of simulated process printing are multiple—individual print runs looks the same from start to finish, prints are more likely to look the same from one print run to the next, and the colors of a simulated-process print are more vibrant than any other of the print methods. A good print shop printing simulated process can hold fine detail and get some beautiful reproduction that holds up. 

In general, the rule for choosing between the methods is to look to something digital for short runs, to traditional process for either lower cost or for images too complicated for simulated, and look to simulated process for more punch, particularly for longer runs.