UVA LEDs - Cure your Coatings in Seconds
What is UV curing
It’s a photopolymerization process that uses UV energy source (the Ultra-Violet light) to transform a liquid into a solid. With the absorption of the UV energy, the photoinitators contained in varnish, ink, adhesive or resin in the liquid state produce substances called free radicals, that react with the chemical compounds of the liquid substance, turning it into solid, by way of “polymerization” process.
In the traditional UV curing process, for many years quartz discharge lamps have been used, they contain mercury and sometimes other substances, called halides. These improve the UV emission at certain frequencies (nm) where photoinitiators reacts better.
The full spectrum of ultraviolet radiation is commonly subdivided into UV-A, UV-B, and UV-C. Any light source spectrum wavelength ranges from
Ultraviolet Light (UV-C: 200 to 280nm)
UV-B: 280 to 315nm; UV-A: 315 to 400nm)
Visible Light (400 to 760nm)
Infrared Light (760 to 3000nm)
The advent of UV LED brought quantum change with many advantages in curing and drying industrial processes.LED UV lights have a narrow spectral output centered around a specific wavelength, ±10nm. The Curing Systems use 365nm, 385nm, 395nm or 405nm light. This near-monochromatic distribution (see chart) requires new chemical formulations to ensure proper curing of inks, coatings, and adhesives.
UV LED vs. Mercury Spectral Distribution
While the UV curing happens in a narrow emission range., the Mecury Curing Lamps produce additional spectral output generating unneeded and potentially harmful UV-C and infrared emissions. Whereas the UV LED lights produce exact wavelength in narrow emission range. UV LED curing light sources efficiently convert 20-40% of the input electrical power into usable UV light with no harmful UV-C or infrared exposure. resulting in 80% power and heat savings over mercury based lamps.
The production of UV LEDs is a complex process because it involves a very high know-how in micro electronics, optics and thermodynamics, to get technologically advanced results and high quality and efficiency products. LEDchip Indus for many years has been investing resources in this field and today offers the complete range of LEDs & UV LED Modules with excellent characteristics and expected long life, among all the lamps currently available on the market.
How is made an UV Led lamp ? A LED semiconductor is usually a small area (less than 1mm side) light source with limited power, so many of them are necessary to get enough UV light. LEDs arranged in high density matrix allow to reach high UV intensities (w/cm²) with compact design. The UV power generated reaches the necessary level for curing paints, inks and other products with UV photoinitiators.
LEDchip Indus Series of KLSL2835UVA LEDs come with 4 bands in 365 to 405nm.
Also visit us at www.indiamart.com/ledchipindus
UV curing technology is utilized for drying inks, coatings, adhesives and other UV sensitive materials through polymerization. UV LED improves on that existing process by enabling thinner, heat-sensitive substrates while reducing harmful byproducts such as ozone, and improving workplace safety. Additionally, UV LEDs turn on and off instantly, and utilize input power efficiently to enable lower operation costs over the application lifetime. LED UV curing products come in a variety of sizes to match your application needs, in both ambient air-cooled and water-cooled solutions.
The irradiance of a UV LED (e.g. 395 nm) is significantly higher than the irradiance of a UV medium-pressure lamp for the same wavelength.