When printing an entire shirt, two primary textile inks are used. The two inks are equally well-liked. However, they serve completely distinct functions in the real world.
It is common practice to use plastisol ink for printing on final products like T-shirts, sweatshirts, jackets, and tote bags. Yard products, whether they come in individual pieces or rolls, are often printed using water-based ink. There are technological benefits and drawbacks to using either ink for various tasks. h has its own environmental effects that must be considered in light of the application’s specific requirements and the manufacturing facility’s layout.
Plastisol ink contains almost no solvent in a PVC system. It’s part of what’s called a “100% solid ink system,” together with UV ink used in graphic screen printing. When the printed ink sheet is heated to a high enough temperature, the molecules of PVC resin and plasticizer cross-link, resulting in a solid, or “cure,” making plastisol a thermoplastic ink. Most plastisol for textile printing has a curing temperature between 300 and 330 degrees Fahrenheit.
1. One of the finest ways to characterize plastisol is as a user-friendly ink.
2. For long lengths of time, plastisol will not cause the printing frame to become clogged. More than 90% of the time, you can use it straight from the container. A variety of formulas are available, allowing plastisol printing on both white and dark materials. Moreover, in many cities, plastisol trash can be disposed of in a straightforward manner.
3. However, plastisol does not dry. Evaporation of a solvent is required for a chemical to dry. Plastisol doesn’t dry since it contains almost little solvent. This property enables the leaving of plastisol in screens and the uncapped storage of ink (although keeping them covered is a good practice to keep lint and dirt out of the ink). Even leftover ink from a project can be safely refilled and reused without affecting the quality of the ink. This final method is really helpful for cutting down on trash.
4. Unlike other specialty inks, printers rarely if ever need to adjust the plastisol ink. They can use it right out of the bottle, without watering it down or thinning it out.
5. The opacity of the plastisol used in screen printing can range from very invisible to completely opaque, and most pigments will have a wide range of plastisol strengths to accommodate the range of garments colors, and textures they work with. Extremely opaque ink is the most expensive, largely due to the higher cost of the additional pigment used to achieve that level of opacity. It is therefore essential for efficient store management that the appropriate degree of opacity is used for each garment.
Challenges Presented by Plastisol
1. Plastisol consists of PVC particles, therefore it will remelt when exposed to a sufficiently heated object. Plastisol prints cannot be ironed. The ink on a print will run if an iron is used on it.
2. As with other types of ink, plastisol ink produces a coating that can be felt when touched. The greater the ink’s opacity, the heavier the hand. Consumers see this heavy hand as a drawback. Maintaining a clean ink supply is a must while working with plastisol.
3. As a result, it is crucial and economically sensible to prevent dirt, lint, and other ink colors from contaminating plastisol hues. Less ink will be wasted if the business is kept tidy. Once the ink has been cleaned, it can be put back into the original cartridge. As long as plastisol is not combined with other colors, tainted by other substances, or unchanged.
4. Plastisol that has been tainted by inks of various hues can be saved for later use by keeping it in a separate container. This excess ink can be recycled into other colors or over-pigmented with new pigment to produce a dark hue, like black, for use on less important projects.
5. The amount of discarded plastisol ink can be cut down to almost nothing with careful management. Most municipalities don’t classify solidified, useless plastisol products as hazardous waste (cured). It is advisable to heat the trash can to 160 degrees and have enough time to cure the ink completely. A one-gallon container of plastisol can fully cure in about an hour under normal conditions.
6. Plastisol in its uncured state must be disposed of by legislation governing the disposal of hazardous chemicals. Always check with local regulatory bodies before disposing of anything, cured or uncured.
7. Cleaning screens and other equipment cortisol use poses the greatest threat to the environment. A solvent is needed to emulsify the ink so that it may be easily removed from screens, squeegees, flood bars, spatulas, and work surfaces. To reduce pollution, used ink and solvent must be disposed of away correctly.
Screen printers have taken the initiative to develop tools that lessen the necessity of such cleaning procedures. It’s easy to get your hands on solvents that are better for the environment than the standard petroleum-based ones. Furthermore, many different types of filtration and cleaning systems can be used For solvent residues, thereby reducing the amount of solid waste that is flushed down the drain.
Dye or pigment suspensions in water are used to create water-based ink. For the ink to dry, the water must evaporate. Depending on the type of water-based ink and the required output rate, this drying can be accomplished either at ambient temperature or using a forced-air dryer.
Systems for Printing with Water-Based Inks
Inks that rely primarily on water as a solvent are said to be water-based. However, that doesn’t make water the only solvent. It’s important to remember that many water-based inks also use co-solvents, some of which may be derived from petroleum. There are a few different reasons why these co-solvents are utilized, but one of the most common is to shorten the curing time and temperature of the ink layer on the fabric.
Pros of Using Water based inks
1. When a gentle touch is preferred, water-based inks are a wonderful option. While the ink deposit is so thin that it is barely perceptible when running a hand over the fabric’s surface, we say that the fabric has a soft hand. This effect is commonly cited as proof that water-based is superior to plastisol, despite the latter’s greater hand.
2. In addition to its other benefits, water-based ink is an outstanding ink technology for high-velocity roll-to-roll yardage printing. This kind of printing requires enormous, high-tech machinery with a massive drying (curing) capacity.
3. Towel printing, for example, benefits from the ink penetrating the towel fibers, hence water-based ink is a viable option. Due to the high nap of towels, special printing techniques are required to ensure that the ink reaches the base fabric.
4. We recommend using water-based inks that are formulated to wick into the fabric for this purpose. Most other types of cloth printing would suffer greatly from ink wicking since it would ruin the pattern and registration of numerous colors.
Water-Based Ink’s Drawbacks
1. Compared to plastisol, curing water-based ink is a lot more of a hassle. A printing firm that wants to use water-based ink must have a way to evaporate the water before printing. Dryers for water-based printing are more essential than those required for plastisol printing. For the printing process to succeed with plastisol inks, the ink film must be heated to cure temperature for only a fraction of a second. To completely dry out water-based ink, it is necessary to bring it up to a certain temperature and keep it there until the water evaporates. Water-based inks that air dry are available, but their low output is mainly limited to hobby printing because of their demand for curing time and space.
2. If you add a catalyst to your water-based ink, the curing process will speed up even if not all of the water is evaporated in the drier, which is useful for many applications. One drawback of usToyst is that it reduces the pot life of water-based ink, meaning that it must be used up before it spoils. The typical pot life for catalyzed water-based ink is between four and twelve hours. To avoid ink drying on the screen while using water-based inks, special precautions must be followed. Water-based ink can clog the mesh and destroy the screen if it’s kept there for too long.
3. If you’re a professional in textile printing who uses water-based ink, you know that you can’t let a screen rest for too long between prints, or the specialty ink will dry and ruin your next print. While this problem is less prevalent with today’s water-based inks, it is still something to be wary of. It is also necessary to remove the ink and wipe the screen when a water-based print job is expected to take more than a day. On the following workday, the ink is replaced in the screen and production resumes.
4. Also, when compared to plastisol, water-based ink is much more aggressive towards the emulsion used to make the screen stencil, which might lead to some unwanted results. For printing with water, you’ll need the special water-resistant emulsions that all emulsion producers now produce. Water-based ink will melt normal emulsion and ruin the stencil in minutes if you use it with water-based ink. Water-based printing often has a shorter screen life than plastisol printing, and that’s with the right emulsion.
Cleanup of Water-Based Ink
It’s often assumed that since we can use water to clean screen print screens, squeegees, and equipment, we can just dump the wastewater into the sewer. On the other hand, water-based ink is not entirely water. Pigments, binders, thickeners, and even co-solvents can be found in these traditional ink smears.
Even so, solid-capture screen-cleaning methods come highly recommended. In addition, uncatalyzed water-based substances can be recycled back into their original containers. Catalyzed ink is a hazardous waste unless it can be completely dried out (all water and solvent removed) before disposal. Do not try to dry it out; instead, treat it as hazardous garbage.
When you screen print, whether it’s with plastisol or a water-based ink system, you’re still producing a chemical compound. As a result, safe methods of disposal and storage must be used.
As previously mentioned, every ink system has its benefits and drawbacks. Use the right ink for the job, produce as little waste as possible, and always do the right thing with your trash.
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