UV light curing health and safety issues

In the past decade, UV-curable inks, coatings, and adhesives have become popular in the printing industry. However, people are still doubtful about the safety of UV light curing technology. People are worried that UV light curing inks, paints, and adhesives will have the potential to harm human health and safety just like all chemicals. In fact, such fears are not necessary. In many cases, UV light curing materials do not actually have this problem.

Understanding the link between UV-curing inks and health and safety is important so that we can properly treat and handle UV-curable inks. The purpose of this paper is to identify health and safety issues related to UV light curing technology and compare it with related issues in traditional printed materials. Because there are many companies that produce UV-curable inks, these companies have more say in their products. For specific products that involve specific health and safety issues, it is best to consult and understand the manufacturer.

In the print shop, there are three ways to get access to chemicals, namely ingestion, inhalation and skin contact. In general, UV-curable inks, UV-coated materials, and UV adhesives contain very few toxic substances. Of course, we recommend not taking these substances into the mouth. However, bad health habits can cause these substances to enter the mouth unexpectedly. For example, there is no hand washing or no hand washing before eating. After touching the food and drink, a small amount of toxic substances may enter the mouth. Following the following health habits, it is easy to avoid this problem, that is, whether it is UV-curable ink or traditional ink, we must be careful to avoid chemicals into the mouth.

One of the major problems with traditional printed materials is that the chemicals contained in their chemical compositions are volatile, and volatile substances can release gases. Workers in the printing shop can inhale these toxic gases during breathing. Typical UV ink components do not contain solvents and VOC (volatile) substances and therefore have little effect on human health. The following table compares the toxicity and chemical properties of several typical UV light-cured materials and several solvents. TMPTA is a trimethylol triacrylate, which is the most commonly used monomer in UV light curable materials and electron beam (EB) curable materials. In many UV inks and EB-cured materials, the copolymer used has a much larger molecular weight than other copolymers. However, the copolymers listed in the table are the same as those of many copolymers.

In addition to breathing and ingesting toxic substances in the UV light-curing material from the mouth, the contact of the human skin with the material also affects the health of the human body, ie, skin allergies. After reading the above table, one might say that the effects of UV light-cured materials and solvent-based materials on human skin are not significantly different. In an idealized environment, such as laboratory testing, the above statement is correct. However, there are some differences in the actual working conditions. This is because the solvent-based material is volatile and the duration of human skin contact with the solvent material is very small in a typical print shop. The UV material is not volatile, and the contact between the human skin and the material lasts for a long period of time. It does not end until it is cleaned. For such a long duration, UV inks have a greater impact on the skin than a solvent-based material in the real working environment.

Acrylates are used in UV materials and can also affect human health if they are in contact with human skin. That is, if a person is not currently allergic to this substance, long-term exposure can lead to skin allergies and allergic reactions. Each person's metabolism is different, so the health impact on each person is also different. It's best not to joke about your own health and avoid contact with this substance whenever possible.

The UV lamp system is another safety issue involved in UV light curing. The UV lamp system is an essential part of UV light curing technology. Unlike other electron and heat cures used in curing, UV light curing technology introduces intense UV light in print production. Fortunately, the amount of light reflected by the UV light from the surface of the substrate is not large. This means that if the printer is not directly exposed to intense UV light or UV light from the reflective surface, there is usually no need to worry about being exposed to a lot of UV energy. The reality is that visible light does not mean that there is a lot of UV light. In general, visible light escapes from a well-designed UV light system is minimal. Even if a large amount of light escapes, it can be protected with a protective cover. Manufacturers of UV light systems are aware of these common senses. They use an instrument to inspect UV light and it is easy to determine if there is a problem.

Another health issue associated with UV lamps is the production of ozone. Shortwave UV light interacts with oxygen to generate ozone. Although there are "no ozone" UV light systems on the market, the negative effects of photocuring continue to be apparent. After seeing negative results, not many people will continue to use this "no ozone" UV light system. Many UV lamp system manufacturers have come up with a solution to the ozone problem, excreting the generated ozone from the work shop, and also achieving the purpose of cooling the UV lamp. Since ozone is an active chemical, ozone released from the excretory device is re-degraded to oxygen.

Compared with conventional solvent-based and water-based inks, UV inks are superior to UV-cured materials in other environmental-related issues. UV-cured materials do not contain any volatile substances (VOCs), but generally do not contain any of the chemicals that are prohibited by Article 330 of the U.S. Super Fund Regulation and Re-delegation Treaty (SARA), nor do they contain hazardous gas pollutants ( HAP). As long as the UV materials are not contaminated by the contaminants, UV curable materials are generally not listed as hazardous contaminants.

UV light curing technology has no negative impact on the environment, allowing California's South Coast Air Quality Management District to allow more UV light curing and EB-curing printing companies to enter the Southern California coast. This move received the attention of the EPA (Environmental Protection Association) and held a hearing in the National Assembly. At the hearing, the EPA stated that in order to protect the environment, it is hoped that more and more printing companies will adopt UV and EB electronic curing technologies.

The use of UV light curing technology often leads to a safer working environment. First, solvent-based inks are exiting the ranks of printed materials. Because solvent-based inks dry very slowly and the ink layers are too thick to dry, more and more printing companies are withdrawing from the ranks of solvent-based inks. Printers who have had access to traditional solvent-based inks now tend to favor UV-curing because UV ink plates are easier to operate. Of course, UV ink printing has also been widely used on narrow web presses. On wide web machines, the use of UV inks is also a trend and trend because UV inks save work time.

Therefore, the use of UV light curing materials in the printing shop is the trend. For print production personnel exposed to UV light-curing materials, how to establish a correct and safe operating concept? The answer is simple, that is, to properly handle and treat the chemicals used in the pressroom. First of all, the most important thing is to read, understand and strictly follow the advice provided by the UV ink manufacturer. After reading and understanding, we must keep in mind that the health and safety problems involved in production can be solved. The UV inks of different manufacturers are still different, and some products are safer than others. Since UV inks are most concerned about the skin's contact with UV inks (breathing and entering the mouth without any problems), the best way is to establish a rule to avoid or minimize exposure to UV inks; whenever possible, try to Put on protective work clothes, gloves and glasses, and even a protective cover that protects the entire face. In addition, if UV ink is accidentally touched during work, wash the exposed area with soap and water. Do not use solvent-based inks because it is not good for human health!

Reprinted from: Guangdong Printing Network