Artistic Denim Mills has created Safe to touch denim using HeiQ Viroblock

Artistic Denim Mills has created 'Safe to touch' denim using HeiQ Viroblock

Research is ramping up around the world to develop new technologies that tap into growing demand for antimicrobial, virus and bacteria killing fibres and fabrics generated by the Covid-19 pandemic.

For companies such as HeiQ Materials – a Switzerland based textile innovation specialist – the pandemic has "opened a whole new chapter for the development of antimicrobial surfaces and textiles," its co-founder and CEO Carlo Centonze told just-style.

Having researched antivirals already, the company was well poised to launch anti-virus textile treatment HeiQ Viroblock NPJ03 mid-March "just two hours after Switzerland declared a state of emergency and mobilised the army" to fight Covid-19. 

If it had been working from scratch, "a more usual time span to launch a textile treatment is nine to twelve months." 

HeiQ Viroblock NPJ03 is added to a textile during the final stage of processing and utilises anti-microbial silver, whose charge attracts viruses to spherical liposomes which deplete the virus membrane of cholesterol, allowing the silver to kill the entire virus.

"The HeiQ vesicle [the spheres] technology targets lipid-enveloped viruses, such as the SARS-CoV-2 (Covid-19) virus strain, providing rapid virus destruction, while the HeiQ silver technology inhibits the replication of both bacteria and deactivates viruses," Centonze explains. 

Moreover, "the two angles of attack result in a speed in locking down and destroying the virus that is unbeaten in the industry," he claims. HeiQ Viroblock NPJ03 is 72% bio-based using cosmetic-grade ingredients found on the International Nomenclature of Cosmetic Ingredients (INCI) list,ensuring safety, he told just-style, adding it has been certified hypoallergenic, skin-safe and non-cytotoxic.

Protection for clothing

One customer of HeiQ Materials is Italian luxury textile manufacturer Albini Group, which has used the additive to launch a new line of Viroformula fabrics. A note from the Bergamo-based company says the fabrics can kill bacteria and viruses on contact in a few minutes and are effective against H1N1, H5N1, H7N9, Coronavirus (229E), RSV, and more recently, SARS-CoV-2.

A leading manufacturer of luxury dress shirt fabrics, supplying brands such as Armani, Ermenegildo Zegna and Prada, Albini Group says the Viroformula fabrics can be used for all types of clothing, including shirts, jackets and trousers, as well as masks, gowns and other garments. The antiviral properties are said to be guaranteed for up to 30 washings.

Artistic Denim Mills (ADM), a vertical denim mill based in Karachi, Pakistan, that produces fabrics, garments and face masks for the global market, is also treating its products with HeiQ Viroblock NPJ03 to help curb the spread of SARS-CoV-2 with its 'Safe to touch' denim collection.

Ahmedabad, India-based Arvind is another customer, having launched its Intellifabrix brand to market suit and shirt fabrics along with readymade garments and face masks treated with Viroblock. 

The Mumbai-based Donear Group has also partnered with HeiQ to launch an anti-microbial 'Neo Tech' fabric that the company expects to boost its US$175m turnover by 15%.

Meanwhile, Lenzing India, the Indian branch of Austrian fibre major Lenzing, has teamed up with Mumbai-based Ruby Mills to launch the 'H+ Technology' fabric, which the companies say is antiviral, antibacterial and antifungal.

And India's Birla Cellulose has a range of antimicrobial fibres under its Liva brand that could be woven or knitted into a fabric to give products anti-viral and bacterial protection.

Ultrasound based anti-pathogen

Elsewhere, Israeli start-up Sonivia has developed a face mask using what it argues is a unique anti-pathogen fabric. Dr Jason Migdal, microbiology R&D strategist at Sonivia, told just-style the fabric incorporates a novel, ultrasound based, high-efficacy zinc-oxide formulated for maximum dispersal across fibres without using chemical binders. 

This is because the production process uses 'cavitation,' where sound wave frequencies create bubbles of high pressure, forcing reagents into the fabric at extremely high velocities: "It is a lab-verified, universally anti-microbial sono-mechanical textile coating, dedicated to combat...hospital acquired infections and most recent viral pandemics," he says. 

Zinc oxide is a potent antimicrobial agent that continually produces positive ions that disrupt and destroy the lipid membrane of microbes, "including enveloped viruses on contact," he says. 

Sonivia's anti-pathogen fabric was tested at the EU-authorised HygCen Austria laboratory, where it attained a 'log 6' reduction of a Sars-Cov2 (the virus causing Covid-19) equating to a 99.99% reduction after 50 industrial wash-cycles. 

These results would deliver durable virus-destroying abilities that should aid the company secure US Food & Drug Administration (FDA) clearance under an anticipated new category for reusable antiviral PPE (personal protective equipment) to combat global shortages, Dr Migdal asserts.

Nanomaterials

Similarly, Nottingham, UK-based nanomaterial solution provider Promethean Particles has developed an additive including nano-copper particles with claimed strong antimicrobial properties. 

The company is currently "working with fibre manufacturers to incorporate our particles into their processes to impart such enhanced effect into the end product," Dr Selina Ambrose, technical manager, told just-style. 

"We also hold the largest nanoparticle manufacturing plant of its kind in the world with a capacity to manufacture over 1,000 tonnes per year," explains Dr Ambrose, adding: "The cost of such innovative solutions is commercially viable, and not confined to university labs anymore."

Microstructures

In Germany, the Geretsried, Bavaria-based Rudolf Group has launched RUCO-BAC AGP, which combines silver finishing with sophisticated microstructures within an innovative finishing chemical to produce textiles that protect wearers against microbes including viruses and bacteria. 

The microstructures block oxygen-transporting enzymes, halting microbe growth; then they crush disulphide bonds, which are a key element of sulphur-containing proteins that help sustain microbes; and they also interfere with the surface proteins within bacteria and virus membranes.

Rudolf Group is marketing its new line as a scientifically sound and comprehensive antimicrobial textile finish whose effectiveness has been independently assessed and is particularly suited to be worn next to the skin.

German companies have a strong track record in developing such technology. Another example is Haama Europe, based in the Bavarian town of Wolfratshausen (it also has an Italian branch in Lonato del Garda, northern Italy), which sells activated carbon for odour control. 

Haama's technology helps to absorb the odorous bacterial waste molecules produced when proteins and fatty acids within sweat feed these microbes. Od Absorb's structure means "only one gram of the activated carbon material provides the effective surface of more than a tennis court," according to a company note, and "attracts and traps odour molecules in millions of nanopores." 

The trapped molecules escape during washing, dry-cleaning and ironing, which restores the absorption quality of the fabric. Od Absorb patches or inlays recharge and "carry on working for the lifetime of the garment."

Meanwhile, researchers at the Hong Kong University of Science and Technology (HKUST) have developed a Multilevel Antimicrobial Polymer (MAP-1) coating that also kills viruses, bacteria and even hard-to-kill spores. 

Speaking to just-style.com, project leader Professor King Lun Yeung explains MAP-1 was originally designed for use in soft-materials including woven and nonwoven fabrics. It was further developed to work in tougher textiles, such as privacy partition curtains in a Hong Kong public hospital to combat against drug-resistant organisms.  

"MAP-1 can be permanently added as finishing material for textile and apparel to provide long-term protection against microorganisms," Yeung says.

Environmental impact 

In the US, Houston-based Ascend Performance Materials has innovated by seeking to reduce the environmental damage caused by adding silver as an antimicrobial material to textile materials. 

Its Acteev Protect product involves embedding zinc ions into a polymer matrix to make polyamide-based woven, nonwoven and knit fabrics. Zinc ions are "a powerful inhibitor of bacterial growth," says Vikram Gopal, Ascend's senior vice president of technology, being more effective than manganese and magnesium. 

Moreover, integrating these ions in fibres has a lower environmental impact than applying silver as a finish chemical or coating to a fibre, he claims. "That process is water-intensive, and the excess silver has to be disposed of, eventually ending up in our waterways." 

With additional reporting by Barbara Bierach, Jens Kastner, Raghavendra Verma, Brenda Dionisi and Keith Nuthall.