In the two previous installments of our own “Fabric Expert” series, we looked at the printing process, with a focus on dye-sublimation. In fabric printing, however, the led uv printer is simply 1 / 2 of the imaging equation. Depending on the ink you’re using, additionally, you will need some sort of post-printing equipment to complement or complete the printing process.
For dye-sublimation, says Andy Arkin, director of integration for Next Wave Sublimation Solutions, “a printer does you not good unless there is a heat press.” Next Wave offers every one of the components of a whole digital textile printing workflow, including software, printer, ink, paper, fabrics, heat presses, and finishing equipment. They distribute transfer-based dye-sublimation printers, and tend to be a distributor of EFI Reggiani fabric printing equipment.
Before we take a look at heat presses, let’s back an additional and talk for a moment about transfer paper, an often overlooked but extremely important component of the dye-sublimation process.
Dye-sublimation transfer paper contains a special coating that supports the ink laid down during printing. Through the transfer stage, under contact with heat and pressure, the paper releases that ink to the fabric. Dye-sublimation can be used on substrates other than textiles, so you need to choose your transfer paper accordingly.
“You ought to be conscious of the sort of paper you’re using,” says Rob Repasi, VP of Global Sales for Beaver Paper & Graphic Media. “There are papers which can be more desirable for textiles as opposed to hard surfaces like ceramics, coffee mugs, or metal.”
You will find premium multipurpose papers-like Beaver Paper TexPrintXPHR-which are works with both hard and soft substrates, that is convenient if you’re offering a variety of dye-sub-printed products.
The caliber of the paper will largely determine how much of ink gets released, but ink dye load is really a consideration. “Dye load” describes how much colorant (dye) the ink contains relative to the liquid vehicle. The greater the dye load, the less ink you must lay down to get a given level of color. Different transfer papers are thus formulated to be compatible with the dye load in the ink, which is generally a function of the brand name of the printer you might be using-or, that is, the dtg printer manufacturer’s ink set.
Ideally, a transfer paper will release 90 percent of the ink “stored” inside. There is absolutely no quantitative way to measure this, but if you find you’re not receiving the maximum amount of ink out as you think you should be, you might need to switch papers or adjust your color profiles. Alternatively, you might be releasing excessive ink to the fabric, which means you might be putting a lot of ink onto the paper to start with.
“There is actually a misconception of how much ink is actually needed,” says Repasi. “More ink doesn’t suggest more color. You’ll end up with a very poor image by utilizing more ink compared to paper are equipped for.” It’s all a subject of balance. “The right amount of ink with the right color management with the right paper will generate the best possible production of color.”
Printed transfer paper doesn’t must be sublimated immediately. Beaver Paper’s own internal experiments have discovered that printed transfer paper may last for years. “We’ve transferred literally a year or two later and it’s remarkably next to the original prints,” says Repasi. It will obviously rely on the conditions under in which the paper is stored. Still, in today’s fast-turnaround arena of digital printing, you’ll probably never should store transfer paper for even several hours, but if you wish to, you are able to.
First a terminological note. We quite often view the term calender – never to be confused spelling-wise with calendar (despite Autocorrect’s best efforts) – used together with dye-sublimation printing. What’s the main difference from a calender as well as a heat press?
“A calender press is a rotating heated drum meant for feeding continuous materials for sublimating stuff like banners or other long stretches or bulk fabric,” says Aaron Knight, VP of Geo Knight and Co., a manufacturer of a multitude of flatbed and specialty heat presses. “It’s not competent at pressing rigid materials, nor could it be right for doing smaller piece goods.” A calender, then, is really a roll-to-roll heat press.
In the calender, heat is made in a central drum against that the fabric and paper are pressed. The very best-quality calenders use a central drum full of oil that is heated to the desired temperature essential for sublimation, typically from the neighborhood of 400°F. The transfer paper/fabric sandwich is rolled around this drum at the set rate that is, again, optimal for sublimation. A high-notch oil-filled calender will run you about $30,000 to $60,000, but will last for greater than 25 years.
There are additional kinds of cheaper calenders that use electric heating elements as an alternative to oil, but a typical problem with them is inconsistent heat round the circumference or all over the width from the drum. This will cause imaging problems or discoloration during sublimation which, all things considered, is actually a careful balance of your time, temperature, and pressure. “If any some of those three changes, you will not have a consistent result,” said Arkin. “Color is not going to emerge the actual way it should certainly. In case you have inconsistent heat about the press, the sublimation process is definitely not consistent throughout the entire component of fabric.”
Calenders have different width drums, which modify the press’s throughput. The larger the diameter from the drum, the greater fabric can be wrapped around it, and thus the faster this process will probably be.
Calenders transfer the fabric and transfer paper on the belt often made of Nomex. “The belt is really a critical section of the nice tight sandwich you need across the circumference in the drum,” says Arkin. “Cheaper machines have very thin belts, while good machines have belts which can be one-half to inch to three-quarters of any inch thick. If this doesn’t stay nice and flat, sublimation gases can escape.” An increased-quality belt may last approximately five or six years. You can find beltless calenders that are compatible with direct-to-fabric dye-sublimation, where you don’t need to worry about transfer paper.
If you’re not sublimating rolls of fabric but instead cut pieces, the option to a calender is a flatbed heat press. Flatbeds also come in several varieties:
A clamshell opens and closes like its namesake, squeezing the paper and fabric together.
Over a swing-away press, the top platen, which supports the heating element, slides away left or right, rendering it more suitable compared to a clamshell for thicker substrates.
A drawer press includes a front-loading lower platen that, if the fabric and paper are loaded, slides back place along with the heating element is brought down on the top of it. There are specialty heat presses that may accommodate stuff like mugs, plates, caps, along with other three-dimensional objects.
Typically, a computerized timer can pop the press open after a desired transfer time to prevent overheating, particularly when an operator is attending to multiple presses.
There are newer “all over sublimation” flatbed heat presses with heating elements on the very best and bottom that essentially “duplex” dye-sub transfer, which is wonderful for applying continuous graphics to either side of, say, a T-shirt.
In relation to choosing a flatbed press, says Knight, “the product the consumer is printing, and the volume they may be doing, will dictate which of these choices is appropriate. Also, the actual size of the goods they are printing will direct them towards a few narrowed-down options for heat presses.”
If you work with a flatbed heat press, you might need to use “tack” transfer paper, that has an adhesive applied that, when activated by heat, keeps the paper in touch with the fabric so there is no shifting throughout the sublimation process, which can cause blurring or ghosting. Tack paper isn’t usually required when you find yourself by using a roll-to-roll heat press, except if you’re sublimating onto an incredibly elastic fabric that may stretch mainly because it moves from the calender, creating a distorted image whenever it relaxes after cooling.
If you are sublimating to highly stretchy fabric, you might need to make amends for stretch prior to printing. “You establish just what the shrink or stretch is perfect for a particular material, so you build those distortions in your files whenever you print them,” says Arkin. “Every time you handle that exact fabric type, you print it the very same way so you receive a consistent result.” It’s similar to color profiling, in many ways.
Even if you are doing direct-to-fabric as opposed to transfer-based dye-sublimation, you still should run the printed fabric using a calender to fix the ink onto the fibers of your polyester, along with the same quality and consistency concerns apply.
Regardless of whether you’re printing with other sorts of dye or pigment inks – not sublimation -you continue to need some form of pre- or post-therapy for the material. Reactive and acid dye inks require steaming after printing, then washing to get rid of excess ink. This is one reason why dye-sublimation is really attractive for fabric printing; these dexjpky05 ink types can require a great deal of water.
No matter the specific configuration of heat press, you don’t desire to skimp on quality. “Look for same-day support and longevity; in a word, quality,” says Knight. “In the machine world, especially with heat presses that reach high temperatures and high pressures, you want one which will last decades, not just months or quite a while. A A4 UV Printer gives you quality results and builds your organization – an unsatisfactory press puts you out of economic.”
“The right heat press is the thing that separates you against having the capability to produce an okay graphic vs. an excellent graphic,” says Arkin.
Next month, from the fourth installment on this series, we shall glance at the finishing process: sewing, welding, and a fast-growing method of fabric finishing, especially for signage, silicone-edge graphics.