Fibers are the basis for a nonwoven wipe. Whether it be staple fiber or a continuous fiber – fibers are the heart of the wipe, as they dictate key physical properties.
There are a number of web-forming technologies that employ fibers in a web in conjunction with bonding process to make material for a wipe. Most disinfectant wipes are manufactured as a drylaid web formation and bonded mechanically through a hydroentangling process (sometimes referred to as spunlacing).
As a bonding process, hydroentangling leads all processes by far in the cleaning and disinfecting wipes market due to its high strength, low cost and a structure that is suitable for the task.
Wipes are an important technology for minimizing the impact of viral outbreaks like COVID-19 because they are a tool that is premeasured, premoistened and not susceptible to human error – in that they require no mixing or measuring to be effective.
Bacteria vs. virus
Bacteria and viruses are both too small to be seen without the aid of a microscope, but that is where the similarities end – they are as different as mice and men.
Bacteria are single-celled microorganisms, and they are huge in comparison to a virus. Bacteria are relatively complex single-cell creatures, which can reproduce on their own on a hard surface and/or on the skin. They can cause infection but they can also be helpful. The only way to stop them is by killing them, as even a small fraction of bacteria can reproduce quickly.
Viruses, on the other hand, are not actually living and are not cellular. They need a host to reproduce by entering and multiplying inside the host’s cells. Viruses can also reside on hard surfaces and the skin, but they can’t reproduce there. However, unlike bacteria, most viruses cause disease, and a virus is not really killed, it is deactivated. When deactivated on a surface, it has no means of replicating.
This distinction of how the threat is eliminated is important because when utilizing a wipe, not only do you kill or deactivate, you also remove from a surface through mechanical action, which is significantly different than other means of disinfecting or sanitizing.
Marketing vs. regulatory claims
Nonwovens play a key role in removing or killing COVID-19 at work or at home. It is important to differentiate between marketing claims like “cleaning” and “antimicrobial” and regulated claims such “sanitizing” and “disinfecting.”
Cleaning refers to the removal of germs, dirt and impurities from surfaces. Cleaning does not kill germs, but by removing them it lowers their numbers and the risk of spreading the coronavirus and other infection.
Antimicrobial refers to a general killing agent that destroys or inhibits growth of microorganisms, but is not specific.
Sanitizing refers to the use of chemicals to reduce a microbial population or bacteria, but not viruses since viruses are technically not alive.
Disinfecting refers to the use of chemicals to kill germs or deactivate viruses on surfaces. This process does not necessarily clean dirty surfaces or remove germs, but by killing germs on a surface, it can further lower the risk of spreading infection.
Wet wipes are a great tool for disinfection because they are simple to use. Unlike liquids that have to be accurately measured and still require some form of wipe as a finishing step, wet wipes provide a complete solution for disinfection.
This distinction of how the threat is eliminated is important because when utilizing a wipe, not only do you kill or deactivate, you also remove from a surface through mechanical action, which is significantly different than other means of disinfecting or sanitizing.
Regulatory concerns
In the U.S., the Food and Drug Administration is responsible for sanitizing wipes sometimes called antibacterial wipes. Sanitizers and antibacterial wipes both have a kill rate of 99.99%. Both terms mean the same thing. There isn’t generally a specific call out of organisms that they kill.
Every EPA-registered wet wipe product’s wipe label features a list of organisms that the product is approved to kill. Along with this list is the time it takes the wipes chemistry to kill these organisms and other directions for use. Some wet wipes require a precleaning of the surface prior to wiping with a disinfectant wipe to remove dirt and other soils, and this information is communicated on the label.
In the U.S., the Federal Trade Commission (FTC) enforces truth-in-advertising laws, and it applies the same standards no matter where an ad appears – it could be in newspapers and magazines, online, or on the wipes package. The FTC monitors “kill claims” and other marketing copy for wet wipe formulations. These claims are not regulated by the EPA because they are considered advertising. Federal law states that this information, when appropriate, should be backed by scientific evidence.
Appropriateness for COVID-19
Wet wipes and dry wipes can be utilized to reduce the spread of COVID-19. Wet wipes are a delivery system for chemistries that kill bacteria or deactivate viruses. These products must be validated to perform and meet the claims listed on their packaging. These claims, at a minimum, are directions for use, how long the surface must remain wet to be effective and what pathogens the product is effective against.
Dry wipes do not have kill claims associated with their use. However, there are several products in the market that reference their ability to remove pathogens, dead or alive, from hard surfaces. Third-party testing associated with these wipes show that with water alone, they remove 99.9% of pathogens, including Norovirus, Listeria, E coli, MRSA, and Salmonella. While COVID-19 is a small virus, it is similar in size to Norovirus, which suggests this dry wipe technology may be effective at removing COVID-19 as well.
Technology improvement
Microfibers continue to gain traction in wipes from a performance perspective. As fibers get smaller, they can be become more effective at capturing very small particulate like COVID-19 from surfaces. When utilizing these fibers in a disposable nonwoven wipe they prevent cross contamination that is common in launderable products. These products are also more efficient than standard products based on the fiber. Electrostatically charged fibers also have the capability to attract small particles when wiping a surface and remove live or deactivated viruses from hard surfaces.
Flushability
Flushability is a hot topic during the pandemic because we are living through a toilet paper shortage, which means that folks are substituting and flushing wipes that were not designed to be flushed down the toilet. Another reason why there has been a significant uptick in wastewater issues is that there is a dramatic increase in disinfection wipes use, and some of those wipes are being flushed inappropriately.
Some wipes are designed for flushing, and others are not designed for flushing. The user must be aware of which types of wipes are appropriate for flushing, as flushing a wipe that is not designed to be flushed can cause plumbing and wastewater treatment issues. To help in this regard, the wipes industry and wastewater developed standards to ensure packaging clearly shows whether or not a wipe is appropriate for flushing.
Looking past the pandemic
As I look into the future, the COVID-19 outbreak was a wakeup call for disinfection and sanitization at all levels. I think Sun-Tzu said it best, “In the midst of chaos, there is also opportunity.” These uncertain times are birthing a new normal in which cleanliness and cleaning protocols have been heightened and changed. As a result, there will be new products for hand and surface sanitization with wipes helping to lead the charge, since they are capable of both killing/deactivating through chemistry and removing through mechanical action. I believe that finer fibers with higher surface areas combined with simple chemistries, like general surfactants and water, will increasingly be employed to break down the protective fatty layer of the virus to deactivate it.
One thing is for sure, the future will be one of the cleanest in history.
As INDA’s director of education and technical affairs, Chris presents regular training related to nonwovens and filter media from INDA headquarters in Cary, NC. For more information about upcoming training opportunities, visit inda.org/education.
