UV-A/EB Curing: Good or Bad?Posted 10/18/2005
By Rachael J. Mercer
Perhaps no new technology contains as much potential in the automotive collision repair industry as does UV-A technology. When talking with other shop owners or automotive representatives, perhaps you've heard about technology to cure and repair vehicles using ultraviolet technology referred to as "Ultraviolet (UV)/Electronic beam (EB)." Actually, the technology referred to as UV/EB would never be used to repair a vehicle.
Bradley Richards, manager, Coatings Research and Development, BASF, explains: "Electron beam is a very high energy source that has some special applications and utilities, but it would never be considered for automotive repair and refinish."
In fact, the ultraviolet technology designed for refinishing an automobile is referred to as "UV-A." In layman's terms, UV-A is the ultraviolet light that is used in tanning beds. Its frequency is safe, with low-intensity. UV-A has less harmful rays than UV-B light, which can cause severe burns and blindness, and UV-C light, which is used to sterilize air and water. UV-B and UV-C processes require a tightly controlled environment for curing, which can be expensive and difficult to maintain, in order to protect workers. Hence, UV-A technology can be best used in the body shop setting. On the other hand, UV/EB curing technology is used on thousands of products, like cereal boxes, high quality periodicals, production of DVDs and CDs, contoured headlamp assembly and more.
How It Works
Now that we understand the name of the curing technology - UV-A, not UV/EB, let's look at the ways that UV-A technology can be used in your body shop. Typically, when a customer brings his banged-up automobile to your shop, you begin the lengthy process of repairing his dents and dings. Perhaps you smooth out the metal, mix materials together and begin filling holes to form a smooth surface. Typically, you would bake the entire vehicle in a booth to be sure the primer dried and was cured.
But, have you ever taken time to consider the energy required to heat the booth to the required temperature? Or have you ever lamented that you must heat the entire booth just to cure a small area? Perhaps you've experienced a jam-up of repairs, particularly small ones, which must be put on hold while each automobile takes its half-hour curing time in your baking booths.
This is where the promise and largest advantage of UV-A technology for automotive repairs is seen - in conserving energy costs and significantly decreasing the time it takes to complete the curing process.
In the UV-A curing process, an automobile is brought into your shop and you begin the repair process. The ultraviolet primer is placed exactly on the spot you need to repair, which will usually be a small dent or a place with slight surface roughness. After a quick application (no mixing required), an ultraviolet light shines on the primer, and in a lightning-quick two minutes, the primer is dried and ready for sanding and then a topcoat application in the traditional spray booth. At face value, this application - a quick-drying primer and UV-A technology - seems like an easy choice for collision repair shops to adopt. However, there are several things that should be taken into consideration before assuming that UV-A advances will take care of all your collision needs.
Typically, UV-A curing processes and the quick-drying primer are best used on small repairs. There are two options for the lamps that can be used to cure the primer. One type of lamp that can be used is a mercury vapor lamp, which delivers a higher intensity of UV energy. This lamp, which is ideal for small repairs, has a visible light and a fairly lengthy life. According to Gareth Hughes, technical director, North America, PPG Automotive Refinish, "standard bulbs will last roughly 400-500 hours. Over the life of the bulb, this equates to between 4,000-6,000 repairs, depending on how often the bulb is turned off and on." These lamps can be expensive to replace; to determine if this lamp for your UV curing is an affordable option for your shop, you would need to consider the number of repairs that your shop does each year. In addition, your shop needs to consider the types of repairs that it does, and how many more repairs you might complete if you had this technology.
The second type of lamp that may be used in UV-A curing repairs is a fluorescent bulb. The fluorescent lamp technology is capable of curing primer on larger areas, as its illumination is larger. The intensity of these lamps is much lower than with the mercury vapor lamps, but they have a shorter cycle time. (Cycle times will be addressed shortly.) While this lamp is able to cure primer in larger areas, it is still unable to handle curing in places such as wheel wells.
This is perhaps one of the largest areas of concern for shop owners with the introduction of UV-A technology. For the UV primers to cure, it must be "hit" directly with a UV lamp (either a mercury vapor lamp or a fluorescent lamp). Without the direct contact with the ultra-violet rays, the primer will not set. Unfortunately, small lamps have not yet been developed that would reach into small crevices and wheel wells. That technology is advancing as companies develop lights and lamps that are increasingly larger, to allow collision shops to repair two to three panels or even an entire car at once.
One concern that many shop owners may have surrounds cycle times. Shop owners considering using UV-A technology have been misinformed about cycling times, which involve the time needed for a lamp to warm up or cool down before and after a repair. "In the case of the mercury vapor lamps, there is a warm-up time - usually 4-5 minutes - before they emit the UV spectrum that we want for the curing," says Richards. When these lamps are shut off, the bulb must be cooled down before it can be restarted, and typically the cool-down time is 10-15 minutes. The misunderstanding concerning these lamps, however, is that it is believed they must be shut off after each repair, or that significant delays occur because of a cool-down and warm-up period.
This understanding is a myth, however, because the mercury vapor lamps can be used repeatedly on one car or on many which are waiting for curing and repair in your shop. For safety reasons, Underwriter's Labs has created a regulation requiring that these mercury vapor lamps include a shutter mechanism so that the lamp can stay on, but few UV wavelengths are emitted. In addition, the fluorescent lamps require no warm-up or cool-down time, and are turned off and on quite easily.
Collision shops - in all the processes involved in their workday - must consider both their employees' safety and the impact their business will have on the environment. Because of the previous explanation about the types of ultraviolet light, their wavelengths and how the wavelengths work, it is obvious that in the UV-spectrum, UV-A is the safest type of light that can be used for curing primer on automobiles.
But, how does UV-A technology affect the environment? Actually UV-A curing is a safe alternative for automotive repairs. According to RadTech, an industry association that specializes in developing UV-A and UV/EB technology, "ultraviolet curing products emit less volatile organic compounds (VOCs) or Hazardous Air Pollutants (HAP) than alternatives." Coincidentally, the Environmental Protection Agency (EPA) estimates that the third largest contributor to climate change comes from the byproducts of solvent emissions. UV-A curing technology does not contain isocyanates, which means no masks are needed specifically because of the UV-A processes. Masks should still be worn to protect your employees from aerosols in the air. Overall, UV-A technology appears to be the safest process for curing - both in relation to preserving the environment and in preserving the health of your employees.
Additionally, because there are limited emissions or waste products put off from the UV-A curing, another step in the typical repair process is eliminated. There are no steps for disposal required, no careful handling of toxic materials, and no EPA regulations for this curing process because there are no wastes or byproducts.
As UV-A technology progresses and develops, perhaps the myths surrounding it will be dispelled. As people come to understand the advantages, as well as the realistic costs and procedures, certainly more collision centers will come to adopt the processes in their day-to-day operation. As it stands, a number of companies are continuing to develop lamps that are shaped differently, or that are smaller or larger - all in an effort to make using the UV-A technology easier. Additionally, companies like BASF, PPG and DuPont continue developing primers and refinishing procedures that will allow collision shops to harness the technology and the promises that UV-A offers.
Is It Right for Your Shop?
As you begin to weigh the advantages and disadvantages of using this UV-A technology, keep an open mind. Be sure to get as many facts (and not assumptions or rumors) as possible. Talk with your paint representatives, and talk with representatives with whom you are not as well acquainted. Take each opportunity you can to review the changing technology, and to understand the advances in UV-A curing as they occur.
When you are deciding whether or not to begin using the UV-A curing technologies, come to your debate fully understanding the costs of the systems you are using now - such as the energy required to run your baking booths, and the time that can be lost between jobs. Look critically at the production times and whether you are experiencing any loss of productivity while one vehicle waits for another to be done.
When these facts about your current state of operation are put together with a good understanding of the new technology, you will be prepared to make an informed decision about whether UV-A technology is right for you and your shop.
AutoInc. Web Site |
ASA Web Site |
Crash Parts Legislation: Hot Topic for State |
UV-A/EB Curing: Good or Bad? |
Repair Facility of the Future: How to Survive When Other Shops Are Not |
Express Lanes Benefit Shops of All Sizes |
Guest Editorial |
Tech to Tech |
Tech Tips |
Around ASA |
Shop Profile |
Net Worth |
Stat Corner |
Copyright (c) 1996-2011. Automotive Service Association®. All rights reserved.