What is Ultra Violet (UV)

UV LED - Introduction

 Ultraviolet light occurs between the visible and x‐ray spectrums. The Ultraviolet wavelength range is specified as 10 nm to 400 nm; however, many optoelectronic companies also consider wavelengths as high as 430nm to be in the UV range. Ultraviolet light gets its name due to the “violet” color it produces in the visible portion of the spectrum although much of the output of UV light is not visible to the human eye. 

Current Technological advancement in UV LED's

 UV LEDs have seen tremendous growth over the past several years. This is not only the result of technological advances in the manufacturing of solid state UV devices, but the ever increasing demand for environmentally friendly methods of producing UV light which is currently dominated by mercury lamps.

The current offering of UV LEDs in the optoelectronics market consists of product ranging from approximately 265nm — 420nm with a variety of package styles including through‐hole, surface mount and COB (Chip‐On‐Board). There are many unique applications for UV LED emitters; however, each is greatly dependent on wavelength and output power. In general, UV light for LEDs can be broken down into 3 general areas. These are classified as UV‐A, UV‐B and UV‐C.  Please refer Electromagnetic spectrum chart for UVA, UVB and UVC segmentation

Applications of UV LED

 The “upper” UVA type devices have been available since the late 2000s. These LEDs have been traditionally used in applications such as counterfeit detection or validation (Currency, Driver’s license, Documents etc) and Forensics (Crime scene investigations) to name a few. The power output requirements for these applications are very low and the actual wavelengths used are in the 390nm – 420nm range.

The “middle” UVA LED component area has seen the greatest growth over the past several years. The majority of applications in this wavelength range (approximately 350nm — 390nm) are for UV curing of both commercial and industrial materials such as adhesives, coatings and inks. LEDs offer significant advantages over traditional curing technologies such as mercury or fluorescent due to increased efficiency, lower cost of ownership and system miniaturization. The trend to utilizing LEDs for curing is increasing as the supply chain is continually pushing to adopt LED technology.

The “lower” UVA and “upper” UVB ranges (approximately 300nm — 350nm) are the most recent introduction to the market place. These devices offer the potential to be used in a variety of applications including UV curing, biomedical, DNA analysis and various types of sensing. 

The “lower” UVB and “upper” UVC ranges (approximately 250nm — 300nm) is an area that is still very much in its infancy, however, there is great enthusiasm and demand for this product in air and water purification systems. The introduction of the first commercial UVC LED based disinfection system has helped to move the market forward.

UV LED Solutions - Verentia a Value Enabler

Verentia - Value enabler

 Verentia manufactures LED-UVA, UVB and UVC (Air, water and HNI) disinfection systems, curing systems for solidifying printing inks, coatings and adhesives, among other applications. Here you can take an opportunity to learn the benefits Verentia UV LED technology brings to disinfection, curing, printing, flexography, converting and other industries; and how it works; and answers to some frequently asked questions regarding LED UV based technology

Recent developments in UV LED Technology

The Surface mount LED is driving the demand for new products in the field of UV curable adhesives, lithography, disinfection or protein detection and synthesis or flouresence detection. UV LED is a key technology because it enables a quick and clean process on curing or printing side or on disinfection side. The high performance UV cured adhesives will provide low viscosity systems enabling high barrier properties, optimal light transmission, low yellowing and good flexibility. This is the ideal solution for the Light Optically Clear Adhesives (LOCA) used in all our smartphones and tablets. 

Advantages - Curing and Printing

  

inks cure instantly, so there is no need for drying time or powder; Printers can expand substrate offerings to include plastics and other materials that don't absorb inks; heat-sensitive substrates can be printed on safely, with quality results;

LED UV lamps last significantly longer (10x) than traditional UV lamps, saving time and money. Verentia LED-UV modules can provide 30,000+ hours of curing, subject to designed operational parameters.

Heat, ozone and mercury are eliminated from press rooms, rendering them safer and supporting customers to improve environmental footprint.

UV inks are free of solvents, so LED UV curing eliminates the release of VOCs (volatile organic compounds)  

Advantage Disinfection

Ultraviolet (UV) disinfection technology has existed for many years, but chemicals are

still very prominent in disinfection applications today. UV disinfection does, however,

provide many benefits over chemical options. It cannot be overdosed, and does not

produce by-products, toxins, or volatile organic compound (VOC) emissions. It does not

require the storage of hazardous materials, and will not affect smell or taste in water

and food disinfection applications

Current challenges in adoption

Any technology will always entail new technical challenges to maximize performance: adhesion, outdoor stability, durability, low migration. New visual or sensorial effects are also a key driver for future developments. We expect to see growing interest in sustainable and compliant formulation approach from the market players, guided by influential brand owners recommendations. 

REACH compliance is also a key subject we are addressing with our customers to ensure a smooth market continuity.

Finally, additive manufacturing is a major area of development today, for which we make the most of our UV curing technology knowhow & experience to provide our customers with the highest quality & performance 3D printing solutions.

Current Progression in UV LED Technology

Today, the perceived advantages of UV LED, including increased productivity, higher quality and a more environmentally friendly technology, has enabled UV LED curing and disinfection to become major and even dominant in many UV curing and disinfection applications, as well as to turn traditional processes to UV. The most important fields where the use of UV LED technology has increased, are wood coatings and printing inks. More recently, the development and marketing of low migration systems specifically developed for use with LED has resulted in a greater acceptance across all sectors of the coating and printing industry where indirect food contact is critical. Moreover, the reduction in heat generated during the curing process has enabled thin film, thermo-sensitive plastic substrates to be employed. This has helped in the rapid development in the flexible packaging applications.

Further progression of UV LED will be based on the development of new wavelength led lamps and/or more adapted photoinitiator packages. 

Industry UV Curing and Printing Solutions

UV Wood and Adhesive Curing

UV curing is a photopolymerization process that uses UV energy to change a liquid to a solid. Upon absorption of the UV energy, the photoinitiator (PI) produces free radicals which initiate cross-linking with binders (monomers and oligomers) in a polymerization reaction to cure or solidify the ink 

 

Verentia uses the most secure way of curing materials (e.g. the printing ink, bonding and sealing materials). This method will provide you with benefits such as high reliability and reduction of process times. It is therefore a cost effective method.

Ultraviolet curing is a fast photochemical process in which high intensity ultraviolet light creates a photochemical reaction that instantly cures inks, adhesives and coatings. This UV curing technology is used in many applications and products, offering a wide range in automated printing and adhesive production processes

UV Printing Solutions

UV inks have been developed for ink jet printing and for use in the variety of ink jet configurations and applications. The industrial applications of UV ink jet range from large-format multi-color graphics to small, single-color marking and identification. These applications can be divided into two general categories – distinguished by the configuration of UV lamps required to cure the inks.

Moving head, wide graphics systems are characterized by print heads that move across the print area. Because the lamps move with the print heads in moving head systems, it is desirable that the UV lamps be small and lightweight. Fixed head, high speed systems are characterized by head arrays that span the print width. Some of the applications include: Product Labels (short run), tags and tickets, Addressing (variable information)/ mailing, Web Printing (variable data stations), Marking (barcodes, date codes - including 2D, part numbers), Wire, Cable, and Connector Marking, PC Board graphics, Sequential Numbering, Gaming pieces and cards, Statements and forms, Plastic cards etc

Industry Applications

 Until recently, mercury arc lamps were the only sources capable of providing high intensity light suitable for Various Industry solutions curing of Industry solutions in Automotive, medical, optical speciality Electronics, Solar Panel manufacturing, SMC curing etc. Thanks to the advances in LED technology, UV-LEDs have become a very attractive alternative to the energy-consuming mercury lamps. Along with the ecological and security aspects, the technical advantages of UV-LEDs as compared with traditional mercury lamps are numerous and significant for providing numerous benefit to Industry. 

The inherent advantages of energy curable products over many other technologies (in terms of processing speed, overall cost and environmental friendliness) can and will be an important driver for reducing customer product device costs as well as improving quality of the product being manufactured.

The data sheet with respect to specific Industry applications are provided for download 

UV LED - Disinfection Solutions

UV and its comparable advantages over other modes of disinfection

Ultraviolet light exists within the spectrum of light between 10 and 400 nm. The germicidal range of UV is within the 100-280nm wavelengths, known as UV-C, with the peak wavelength for germicidal activity being 265 nm. This range of UV light is absorbed by the DNA and RNA of microorganisms, which causes changes in the DNA and RNA structure, rendering the microorganisms incapable of replicating. A cell that can’t reproduce is considered dead; since it is unable to multiply to infectious numbers within a host. This is why UV disinfection is sometimes called ultraviolet germicidal irradiation (UVGI)

How does UV work

 UV has been proven effective against a broad spectrum of microorganisms. Viruses contain RNA or DNA and are thus susceptible to irradiation. Bacteria and fungi both contain DNA and are similarly vulnerable to UV light. Spores are also susceptible to UV. With the longstanding use of UV for disinfection, there is a plethora of information regarding dosages necessary to inactivate different microorganisms. Bacteria are generally easier to inactivate than viruses, with fungi and spores being even harder to inactivate with UV 

Water Disinfection

The upcoming technology of UVC-LEDs promises new inexpensive, environmentally friendly, and long-life disinfection systems for drinking water that can be used decentralized in combination with photocatalytic or photovoltaic or ultrasound systems. UVC radiation (200–280 nm) in general is a very efficient way of inactivating pathogen bacteria in drinking water by directly damaging the DNA. Radiation of this wavelength range is able to enter the cell walls of microorganisms and is partly absorbed by the DNA. By this process, thymine dimers are formed, which prevent further replication of the DNA strains. These thymine dimers arise when an UVC photon gets absorbed by adjacent thymine nucleotides, merging them as shown in Figure. A preferable wavelength for disinfection would therefore be expected at about 270 nm, which is the absorption peak of thymine.

Healthcare Acquired Infection (HAI)

  

HAIs are caused by a range of common pathogens. Each has unique radiation absorption characteristics, meaning they absorb UV photons differently at different wavelengths based on their physical biology. Absorbing this UVC energy inactivates the pathogen’s R/DNA, rendering it inability to reproduce and thus making them harmless.

Unlike traditional UV sources, the far more compact UVC LEDs can be produced at specific deep UVC wavelengths which match the peak absorption capabilities of targeted microbes, resulting in a much more effective disinfection—ideal for quick disinfection of intricate surgical tools, portable and/or countertop devices, or manual point of care sites.

Products and Solutions for Disinfection

Water Disinfection - Point of Use

Point of use or  Decentralized water treatment systems have typical water flow rates from 0.5 LPM to less than 10 LPM. The Point of use water disinfection is designed to target markets such as Residential and commercial applications with lower flow rates. Developing and emerging countries with a lack of high-quality centralized water supply system, the countries of the first world in areas without water network infrastructure, transport infrastructure (eg ships, aircraft, rescue and emergency cases) or incase of hygienic water requirements (eg, hospitals, food and beverages manufacturung ). In these applications, it is advantageous that UVC LEDs can be operated at lower DC voltages and that they are designed from lower maintenance point of view, are mechanically robust and free of toxic substances (mercury). UVC LEDs by far offer a great opportunity for decentralized disinfection segment. 

Water Disinfection - High Flow rate Systems

UV Disinfection for medium and large flow rates during water treatment applications in Industry or equivalent, performance as well as energy efficiency is essential. UV-LED Irradiation point of source should be able to operate with the small mean flows as well at high flow rates for Industrial and desalination applications with lowest power density. While conventional mercury lamps can operated at 30-50% of the maximum power, there is no such lower limit for UVC LEDs. Considering the UVC LEDs were half as efficient as mercury lamps, the advantage of UVC LEDs would clearly support reduction of average power consumption. The energy saving effect, combined with an extended light source life, lower maintenance, new and efficient reactor designs would significantly reduce power consumption in a large-scale solution with a water flow rate in the range 50 ~ 500 m3 / which will help customer realize better operating and capital costs.

Food and Beverages Disinfection

 

UV technology is particularly suited to the beverage, bottled water and food processing sectors, where extremely high standard of hygiene are expected. Contamination of the process at any point by pathogenic or spoilage microorganisms can have extremely serious consequences for manufacturers. Effective microbial disinfection of the whole process is therefore essential.

UV is rapidly gaining acceptance across the whole spectrum of food and beverage industries as a highly efficient, non-chemical method of disinfection. UV kills all known pathogenic and food spoilage microorganisms, including bacteria (including Cryptosporidium and Giardia) viruses, yeasts and molds (and their spores). It is a low maintenance, environmentally friendly technology which eliminates the need for chemical treatment while ensuring very high levels of disinfection.

Healthcare Acquired Infection (HAI) Disinfection Solutions

Ultrasound Probe Disinfection

UVC disinfection is a simple, fast, and effective means to disinfect unprotected ultrasound probes after Anesthesia block placement, and after cover removal following endorectal or endovaginal examination 

Apparently medical equipment and devices also play a central role for causing healthcare associated infections (HCAI). The Ultrasound probe is one of the most used device by medical personnel, and its and related aspects are therefore a crucial question of hygiene. Most surveys show that 50-70% of physicians do not systematically disinfect their probe after each examination. TruSpectra supports the ease of use of Ultrasound Probe which disinfects the probe surface during routine patient examination studies. 

Endoscope Disinfection Solution

UV automated disinfection units provide simple, rapid, Reliable and Ecological disinfection of the endoscope between each patient. UVC disinfection system which produces a dosage of UVC radiation sufficient to kill Clostridium difficile and other pathogens in a simple fast and unique manner.

The use of automatic UV-C disinfection device resulted practical and easy to use Endoscopic devices after disinfection for the health professionals affirming clinical effectiveness of ultraviolet light for the disinfection of device. UV-C irradiation of the device surface showed a marked reduction of bacterial load, confirming its high disinfection capacity.

The Tru-Spectra endoscopy probe is designed to activate the endoscopic device surface upon placement inside the UV reactor housing with inbuilt sensors to irradiate the surface of the probe and auto switch off upon designed time. Standard designed dose is 60 seconds with additional deeper dose of upto 200 seconds for effective fluence.

Stethoscope Disinfection Solution

Common hospital acquired infection (HAI’s) effects patients with certain risk factors that include previous hospitalization, recent antibiotic use, older age and weak immune systems. Apparently medical equipment and devices also play a central role for causing healthcare associated infections (HCAI). The stethoscope is one of the most used device by medical personnel, and its and related aspects are therefore a crucial question of hygiene. Most surveys show that 70-90% of physicians do not systematically disinfect their stethoscope after each examination. TruSpectra supports the ease of use of stethoscope which disinfects the stethoscope membrane during normal hospital activities. 

Surgical and Dental equipment Disinfection Solution

Under Development

Medical Lab Equipment Disinfection

Under Development

Cathetar Disinfection

Under Development

Other UV LED Solutions

Counterfeit detection

 

Every modern banknote has integrated UV security features that only show up under ultraviolet light at a certain frequency. The Verentia CFD is designed specifically to help you verify these. features and identify potentially counterfeit banknotes.

Verentia CFD not only reveals the integrated UV security features in modern banknotes; it also instantly illuminates the UV security features built into today’s credit cards, passports and other ID documents, as well as UV ink applied to protect valuable items from theft or confirm event admission.  

Flourescence

 

Fluorescence spectroscopy, also known as fluorometry or spectrofluorometry, is a type of electromagnetic spectroscopy, which analyzes fluorescence from a sample. It involves using a beam of light that excites the electrons in molecules of certain compounds and causes them to emit light; typically, but not necessarily, visible light. It is a useful technique in many biological (chlorophyll and carotenoid), biochemical (fluorescence diagnosis of malignancies) and environmental applications. 

Fluorescence spectroscopy, also known as fluorometry or spectrofluorometry, is a type of electromagnetic spectroscopy, which analyzes fluorescence from a sample. It involves using a beam of light that excites the electrons in molecules of certain compounds and causes them to emit light; typically, but not necessarily, visible light. It is a useful technique in many biological (chlorophyll and carotenoid), biochemical (fluorescence diagnosis of malignancies) and environmental applications. 

BioScience - Protein detection and DNA Analysis

  The evolution of early reproductive proteins and enzymes is attributed in modern models of evolutionary theory to ultraviolet radiation. UVB causes thymine base pairs next to each other in genetic sequences to bond together into thymine dimers, a disruption in the strand that reproductive enzymes cannot copy. This leads to frame shifting during genetic replication and protein synthesis, usually killing the cell. Before formation of the UV-blocking ozone layer, when early prokaryotes approached the surface of the ocean, they almost invariably died out. The few that survived had developed enzymes that monitored the genetic material and removed thymine dimers by nucleotide excision repair enzymes. Many enzymes and proteins involved in modern mitosis and meiosis are similar to repair enzymes, and are believed to be evolved modifications of the enzymes originally used to overcome DNA damages caused by UV