The primary difference between UV as well as LED UV is the source of light. LED-UV creates energy wavelengths of light-emitting diodes (LED) in the spectrum of light between 385 and 395nm (nanometers.) Traditional UV produces energy wavelengths of between 260nm and the 440nm range from a mercury-vapor light bulb. UV is less effective because only a fraction of the energy produced will be utilized to cure adhesives and inks. The remainder is infrared radiation that produces significant Ozone and heat.
What is the main difference between traditional inks and LED-UV?
Inks traditionally used are solvent-based and dry after the chemical evaporates over time. LED-UV inks dry (cured) instantaneously with UV light.
How is LED-UV printing any different than printing using conventional inks?
LED-UV and traditional printing are essentially the same However, like other modern technologies, there is likely to be a brief time to learn.
Do I need to purchase a new printer in order to be an LED-UV printer?
The LED-UV, as well as the traditional UV curing unit, are able to be retrofitted onto most presses.
Do I need to switch ink rollers so that I can print LED-UV?
Indeed, inks made of LEDs can create traditional rolling wheels to expand and shrink. Additionally, they cause problems maintaining the correct ink/water balance and also generate extra heat due to friction. There are two kinds of rollers for LED UV: EPDM specifically designed to print with LED-UV only and mixed-mode rollers to switch between traditional inks and LED-UV.
Can I reuse my existing print blankets?
No, LED-UV needs special blankets. Similar to rolling rollers, EPDM blankets can be used for printing LED-UV only, and a hybrid blanket is employed to print Mixedmode printing.
Can I use a traditional pressing machine and blanket wash that is equipped with LED-UV?
A specifically UV suitable wash is needed since LED-UV blankets and rollers are made of a different type of rubber in comparison to traditional print blankets and rollers.
Do LED-UV inks actually cost more than conventional inks?
Inks that are LED-UV tend to be more expensive than traditional inks. However, the expense of ink usually is only 1 – 2percent of the overall cost for each printing job. There are many factors that help offset the expense. Inks that are LED-UV enhance the “mileage per pound” of ink, particularly for printing with offset materials since the inks of LED-UV cure directly on the surface of the substrate, thus reducing absorption. Additionally, as more printers begin to make use of LED-UV technology, ink costs will continue to fall. (The cost of LED-UV inks has decreased by 20% in the last two years.)
What other savings on costs does LED-UV offer?
Direct savings are derived from a variety of areas, including the elimination of the requirement to spray powder and fewer MR sheets that are employed. Other LED cost-saving aspects include lower energy consumption and removing the need to rack work. IR dryers produce substantial heat, which causes an HVAC system to operate longer and harder to ensure that the press room is comfortable. A LED-UV system doesn’t produce any heat, and it requires at least 80percent less energy than an IR system. Lack of spray powder makes the surface of the press much clean, which means less time to clean and maintain the delivery, and makes it easier to complete business-generating tasks. Since MR sheets are immediately cured and can be used several times in a closed-loop system that reads their color bars. With LED-UV, jobs do not require racking during delivery. It is no longer necessary to create space for the drying of press loads and improve the flow of work in the production department. Aqueous coatings are frequently given away for free in order to move the project to the finishing department faster. With LED-UV, the days of distributing coatings free of charge are over for good! Coatings are only used when they are an integral part of the design and are they are paid for by the client! The turn times for every job are dependent on the duration of the job, which gives more flexibility downstream as well as a simpler time-scheduling of jobs.
What is the reason LED-UV is “Green” and eco-friendly?
LED-UV curing systems do not produce VOCs (volatile organic compounds) to release into the air, causing greenhouse gases. In addition, unlike conventional UV curing systems, LED-UV is a clean system that contains no mercury and requires less than 20% of the energy as compared to a traditional ultraviolet curing device or IR dryer.
Does the light produced by LED-UV harmful to my users?
LED-UV systems do not emit UV radiation within the UV-A wavelength that is less harmful to humans than the less harmful UV wavelengths produced in the traditional UV mercury bulbs. It is recommended not to look directly at the LED-UV light for prolonged periods of time.
Does LED-UV chemistry cause toxicity?
As with any chemistry used in print shops, protective eyewear and gloves must be worn. There’s no distinction between LED-UV and conventional washes. Inks and coatings that contain LED-UV contain photo-initiators that may cause burning or a rash. These chemicals don’t affect everyone the same way, and, as such, it is suggested that procedures for handling chemicals be adhered to regardless of the kind of printing being used.
Other products for maintenance cleaning needed with LED-UV Printing?
The same roller paste and calcium cleaner products are suitable regardless of the kind of printing. These products are more crucial for printing with LED-UV. Elimination of any contaminants, including photo-initiators and calcium, can help keep the press functioning at its best. Additionally, it’s always a good idea to have a thorough maintenance plan for every mechanical device.
Do I have to use the same plates I’m currently using?
Most CTP plates produced today can be used with LED-UV and UV printing. The main difference is the expected length of the run. Certain plates can produce approximately 250 impressions, whereas others might produce up to 250,000 impressions. If you require more than that, it is recommended that the plate manufacturer is in contact.
Do I have to use the current rubber measuring roller?
It isn’t required to change fountain solutions. In the beginning, it is suggested to try various formulas for the best performance. A two-step fountain solution that includes subs is suggested. It is recommended to use the least amount of sub that is possible to ensure the most adjustment. Certain presses equipped with reverse nip dampening systems are more efficient using a one-step fountain. Testing different options is the most effective way to get the results you want.
Yes, the metering roller works identically for all offset processes.
Do I need to air my press’s message?
It is not necessary to require that the press be vented as LED-UV does not generate any VOCs or heat, so there is no unpleasant smell produced.