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Antimicrobial coatings can provide products with built-in resistance to microbial growth, allowing them to disinfect their coated surfaces continuously. These coatings are used everywhere, from public transit to the International Space Station, and have become increasingly popular over the past few years.

However, these coatings are only effective if mixed properly. Improper mixing may result in inconsistent antimicrobial action or prevent it from working altogether.

Manufacturers must use these best practices to maximize the benefits of antimicrobial coatings.

The Growing Value of Antimicrobial Coatings

Antimicrobial coatings use chemicals and metals to slow or prevent the growth of microorganisms that cause disease, like bacteria, mold and viruses. Typically, these additives are invisible when properly mixed into the coating.

These coatings help make the product fresher and more sanitary by preventing microbes from gaining a foothold on its surface. Microbes can stain and deteriorate coatings, and antimicrobial properties may also extend their life spans and provide extra corrosion resistance.

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Antimicrobial coatings can provide products with built-in resistance to microbial growth, allowing them to disinfect their coated surfaces continuously.

As with other product coatings, an antimicrobial coating can improve a product’s appearance and extend its life span by preventing corrosion or additional damage. These issues can be caused by humidity, exposure to the elements and other environmental threats.

Use-Cases for Antimicrobial Product Coatings

Antimicrobial product coatings are popular in various industries, including the health care, medical device manufacturing, HVAC, food and beverage and textile manufacturing sectors.

The medical device market is currently the largest consumer of antimicrobial product coatings, but they are becoming increasingly popular across the economy. Hospitals may use them to disinfect surfaces, high-traffic areas, important storage units, specialty infrastructure and equipment.

Antimicrobial paints are also becoming increasingly common. The Sherwin-Williams Company recently introduced a new line of surface paint that can kill common bacteria. Other paint companies are working on copper-infused products that will also kill viruses.

The rising demand for antimicrobial products may also help drive growth in the product coating and paint industries over the next few years.

The Proper Mixing of Antimicrobial Coatings

The right mixing technique is essential for creating an effective antimicrobial coating. The wrong method may result in an uneven distribution of chemicals or a coating that is more prone to losing its antimicrobial effect over time.

A manufacturer’s mixing method can also significantly impact an antimicrobial coating’s shelf life. This could potentially reduce effectiveness or life span, especially if they need to be stored before application to a product.

A high level of mixing is often necessary for an antimicrobial coating to remain stable and function properly. A manufacturer can use several mixing techniques when creating an antimicrobial coating. These are some of the most common mixing methods used to manufacture antimicrobial coatings:

Powder Blending

The manufacturer begins with an antimicrobial powder and uses low-speed blending to create a powder/powder coating blend. It can be applied like any other powder coating and is popular for protecting appliances, handrails, storage equipment and tile grout.

Blending antimicrobial powders into a liquid medium is also possible
but requires higher speeds and greater shear. Otherwise, the antimicrobial powder may not be effectively dispersed throughout the coating liquid.

Challenges of this mixing method may include foaming and lumping, though high enough levels of shear and speed will generally minimize these risks.

Antimicrobial powders are also moisture-sensitive and may agglomerate in a liquid medium over time, potentially limiting their shelf and storage life.

Pellet Mixing

The antimicrobial additive is mixed with thermoplastic pellets. The additive then coats or sticks to the pellets, which are melted before injection molding or a similar manufacturing method, like plastic extrusion.

The additive effectively blends into the thermoplastic material during the melting process, ensuring an even distribution throughout the coating or product.

This mixing method is an efficient way to blend antimicrobial additives into plastic products. Common applications of pellet mixing include smartphone cases and thermoplastic kitchenware.

Liquid Blending

High speed-high shear blending means a manufacturer mixes an antimicrobial liquid or pre-dispersed powder into a liquid medium.

The high speed and shear of the blending method help to ensure coating homogeneity.

Other Considerations for Effective Antimicrobial Coating Mixing

In addition to chemical compatibility, viscosity, pH and other technical parameters may prevent a homogenous mixture, and a manufacturer will also need to consider consumer preferences.

Errors made during the mixing process — like oversaturating the liquid medium with antimicrobial additives — can produce functional antimicrobial coatings with aesthetic defects, like uneven coloration, spotting and streaking.

Even if these coatings provide antimicrobial benefits, they may not be up to a manufacturer’s aesthetic standards.

Working with a partner who has experience in manufacturing antimicrobial coatings can help a business avoid aesthetic and functional defects.

Best Practices for Manufacturing Effective Antimicrobial Coatings

A growing number of industries use antimicrobial coatings to protect surfaces and products from potentially harmful microbial growth. Mixing these coatings properly is essential to ensure they provide this protection.

Various mixing strategies exist. Depending on the product being manufactured and the end-user’s needs, certain methods may be more valuable than another. Companies need to determine the best technique for them before proceeding.

ABOUT THE THE BLOGGER Emily Newton Emily Newton is the Editor-in-Chief of Revolutionized, a magazine exploring innovations in science and industry that shares ideas to promote a better tomorrow. She regularly covers trends in the industrial sector. In addition to her work with Revolutionized, Newton is also a contributing author for loT Times and the International Society of Automation. Newton also provides science and tech insights at BBN Times. For more information please visit connect with Newton on LinkedIn or contact her at https://emilyjnewton.com/. SEE ALL CONTENT FROM THIS CONTRIBUTOR