Inside the two previous installments in our “Fabric Expert” series, we considered the printing process, with an emphasis on dye-sublimation. In fabric printing, however, the phone case printer is simply one half of the imaging equation. Depending on the ink you’re using, you will also need some form of post-printing equipment to fit or complete the printing process.
For dye-sublimation, says Andy Arkin, director of integration for Next Wave Sublimation Solutions, “a printer does you no good unless you will have a heat press.” Next Wave offers every one of the bits of a total digital textile printing workflow, including software, printer, ink, paper, fabrics, heat presses, and finishing equipment. They distribute transfer-based dye-sublimation printers, and are generally a distributor of EFI Reggiani fabric printing equipment.
Before we have a look at heat presses, let’s back up an additional and talk for just a moment about transfer paper, an often overlooked but extremely important element of the dye-sublimation process.
Dye-sublimation transfer paper includes a special coating that holds the ink laid down during printing. Through the transfer stage, under exposure to heat and pressure, the paper releases that ink onto the fabric. Dye-sublimation can be used on substrates aside from textiles, so you have to choose your transfer paper accordingly.
“You needs to be aware of the particular paper you’re using,” says Rob Repasi, VP of Global Sales for Beaver Paper & Graphic Media. “There are papers that are more inviting for textiles rather than hard surfaces for example ceramics, coffee mugs, or metal.”
There are premium multipurpose papers-like Beaver Paper TexPrintXPHR-which can be appropriate for both hard and soft substrates, which happens to be convenient if you’re offering various dye-sub-printed products.
The standard of the paper will largely determine the amount of ink gets released, but ink dye load is an important consideration. “Dye load” refers to how much colorant (dye) the ink contains relative to the liquid vehicle. The greater the dye load, the less ink you should set down to obtain a given measure of color. Different transfer papers are thus formulated being works with the dye load in the ink, which is usually a purpose of the brand name of the printer you are using-or, which is, the dtg printer manufacturer’s ink set.
Ideally, a transfer paper will release 90 % of the ink “stored” within it. There is absolutely no quantitative strategy to measure this, but if you discover you’re failing to get just as much ink out as you think you ought to be, you may have to switch papers or adjust your color profiles. Alternatively, you could be releasing too much ink on the fabric, which means you may be putting a lot of ink onto the paper in the first place.
“There is really a misconception of how much ink is absolutely needed,” says Repasi. “More ink doesn’t necessarily mean more color. You’ll end up with a poor image by making use of more ink than the paper can handle.” It’s all an issue of balance. “The right amount of ink with all the right color management with the right paper will generate the perfect output of color.”
Printed transfer paper doesn’t must be sublimated immediately. Beaver Paper’s own internal experiments have found that printed transfer paper may last for years. “We’ve transferred literally a year or two later and it’s remarkably near the original prints,” says Repasi. It would naturally be determined by the conditions under that the paper is stored. Still, in today’s fast-turnaround field of digital printing, you’ll probably never must store transfer paper for even a few hours, but if you need to, you are able to.
First a terminological note. We regularly view the term calender – to never be confused spelling-wise with calendar (despite Autocorrect’s best efforts) – used together with dye-sublimation printing. What’s the real difference between a calender and a heat press?
“A calender press can be a rotating heated drum meant for feeding continuous materials for sublimating items like banners or any other long stretches or bulk fabric,” says Aaron Knight, VP of Geo Knight and Co., a manufacturer of numerous flatbed and specialty heat presses. “It’s not effective at pressing rigid materials, nor could it be ideal for doing smaller piece goods.” A calender, then, is really a roll-to-roll heat press.
In a calender, heat is made in a central drum against which the fabric and paper are pressed. The greatest-quality calenders use a central drum filled up with oil that is heated for the desired temperature necessary for sublimation, typically in the neighborhood of 400°F. The transfer paper/fabric sandwich is rolled around this drum at a set rate that may be, again, optimal for sublimation. A top-notch oil-filled calender will run you about $30,000 to $60,000, but will last for a lot more than twenty-five years.
There are additional kinds of cheaper calenders which use electric heating elements instead of oil, but a standard trouble with them is inconsistent heat across the circumference or all over the width of your drum. This could cause imaging problems or discoloration during sublimation which, all things considered, is a careful balance of time, temperature, and pressure. “If any some of those three changes, you will not have a consistent result,” said Arkin. “Color will not emerge the actual way it is supposed to. In case you have inconsistent heat around the press, the sublimation process will never be consistent over the entire bit of fabric.”
Calenders have different width drums, which impact the press’s throughput. The greater the diameter of your drum, the better fabric may be wrapped around it, and so the faster the method will be.
Calenders transfer the material and transfer paper on the belt often created from Nomex. “The belt is really a critical part of the nice tight sandwich you will need around the circumference from the drum,” says Arkin. “Cheaper machines have very thin belts, while good machines have belts which are one-half to inch to three-quarters of the inch thick. When it doesn’t stay nice and flat, sublimation gases can escape.” A very high-quality belt can last around five or six years. You will find beltless calenders that are suitable for direct-to-fabric dye-sublimation, in which you don’t need to bother about transfer paper.
If you’re not sublimating rolls of fabric but cut pieces, the replacement for a calender is a flatbed heat press. Flatbeds are also available in several varieties:
A clamshell opens and closes like its namesake, squeezing the paper and fabric together.
Over a swing-away press, top of the platen, which supports the heating element, slides away to the left or right, which makes it considerably better compared to a clamshell for thicker substrates.
A drawer press features a front-loading lower platen that, when the fabric and paper are loaded, slides way back in place along with the heating element is brought down on top of it. There are also specialty heat presses that could accommodate things such as mugs, plates, caps, as well as other three-dimensional objects.
Generally, a computerized timer can pop the press open right after a desired transfer time and energy to prevent overheating, particularly when an operator is attending to multiple presses.
There are newer “all over sublimation” flatbed heat presses with heating elements for both the most notable and bottom that essentially “duplex” dye-sub transfer, which is wonderful for applying continuous graphics to both sides of, say, a T-shirt.
With regards to picking a flatbed press, says Knight, “the product the user is printing, and also the volume they can be doing, will dictate which of such choices is appropriate. Also, the actual size of the item these are printing will direct them towards several narrowed-down selections for heat presses.”
If you are using a flatbed heat press, you might need to use “tack” transfer paper, which contains an adhesive applied that, when activated by heat, keeps the paper in touch with the material so there is not any shifting in the sublimation process, which could cause blurring or ghosting. Tack paper isn’t usually required if you are using a roll-to-roll heat press, except if you’re sublimating onto a really elastic fabric which can stretch mainly because it moves throughout the calender, producing a distorted image in the event it relaxes after cooling.
Should you be sublimating to highly stretchy fabric, you may want to make up for stretch even before printing. “You establish just what the shrink or stretch is made for a particular material, and also you build those distortions in your files if you print them,” says Arkin. “Every time you handle that specific fabric type, you print it the very same way so you have a consistent result.” It’s kind of like color profiling, in many ways.
Even when you are doing direct-to-fabric as an alternative to transfer-based dye-sublimation, you continue to must run the printed fabric via a calender to solve the ink to the fibers of the polyester, and the same quality and consistency concerns apply.
Even when you’re printing with other kinds of dye or pigment inks – not sublimation -you will still need some kind of pre- and/or post-therapy for the material. Reactive and acid dye inks require steaming after printing, then washing to take out excess ink. This can be one reason that dye-sublimation is indeed attractive for fabric printing; these dexjpky05 ink types can require lots of water.
Irrespective of the specific configuration of heat press, you don’t would like to skimp on quality. “Look for same-day support and longevity; in a word, quality,” says Knight. “In the gear world, especially with heat presses that reach high temperatures and pressures, you need one which may last decades, not simply months or a few years. A uv printer provides you with quality results and builds your company – an unsatisfactory press puts you out of economic.”
“The right heat press is the thing that separates you against being able to produce an okay graphic vs. a wonderful graphic,” says Arkin.
The following month, within the fourth installment of this series, we are going to look at the finishing process: sewing, welding, plus a fast-growing form of fabric finishing, especially for signage, silicone-edge graphics.