After a year of normalized face masks, scientists and medical experts across the country are studying which types of fabric are most effective at protecting us against the coronavirus. Notably, researchers are investigating silk. In September 2020, University of Cincinnati researchers showed that, when compared to cotton and polyester, silk is most effective at preventing small aerosol droplets from penetrating masks in a laboratory setting — including respiratory droplets that carry Covid-19 and are released when a person infected with the virus sneezes, coughs or talks. This is the primary way the coronavirus is spread from person to person, according to the Centers for Disease Control and Prevention (CDC).
Due to its unique hydrophobicity — or ability to repel water — silk successfully helps prevent more droplets from being soaked into a face covering than other materials, explained Patrick A. Guerra, PhD, assistant professor at the University of Cincinnati Department of Biological Sciences and a co-author of the study. Additionally, the study found that silk can help preserve personal protective equipment like N95 masks when a silk face mask is layered over the respirator — a form of double masking — if it needs to be reworn multiple times. But the CDC advises against double masking with respirators like N95 and KN95 masks, specifically advising wearing only one KN95 mask at a time: “You should not use any type of second mask on top of or underneath a KN95 mask.”
“It’s still the wild west when it comes to making face coverings,” Guerra said. “But we’re finding ways to use basic science and apply what we know to improve them.”
We spoke to experts about how to shop for face masks made with silk, and rounded up the best silk face masks on the market from brands like Slip, Vince and more.
Best silk face masks
Slip Double-Sided Silk Face Covering
Slip’s silk face coverings feature 100 percent mulberry silk on both sides, as well as a 100 percent cotton inner lining. The mask features adjustable elastic ear loops, two sets of replacement silicone stoppers and an adjustable nose wire with 10 nose wire replacements. Slip’s silk face is sold with a storage pouch and coverings come in eight different styles from solid colors like Rose Gold and Pink to patterns like Rose Leopard and Horizon. Slip recommends following its pillowcase instructions for cleaning the face coverings — it can be hand washed or machine washed, and Slip recommends air drying the mask. Slip also sells silk wash for cleaning its products.
Vince Silk Face Mask
Vince’s masks are designed with three layers of fabric: a 100 percent silk exterior, a polyester interlining filter and a cotton interior. The mask also comes with a cotton pouch. To wash the mask, Vince recommends soaking it in lukewarm water with gentle detergent or soap, and allowing it to drip dry. For every mask sold, Vince will donate $15 to the American Civil Liberties Union. Masks are available in five colors: Pink, Silver Grey, Ivory, Black and Coastal Blue.
Blissy’s silk face masks are handmade and crafted from 100 percent pure mulberry silk. They come in four colors: Silver, Pink, Black and Tie-Dye. Masks feature adjustable ear loops and are machine washable.
This silk face mask is constructed from 100 percent mulberry silk and is built with an interior filter pocket and adjustable ear loops. The mask comes in 12 colors, including Blue, Dark Purple, White, Taupe and Pea Green.
NIGHT’s silk face mask is designed with three layers of fabric and has a filter pocket. The mask comes with seven disposable filters, too. It features an adjustable nose wire and adjustable ear loops. The mask can be machine washed with cold water on a delicate setting, and it’s available in four colors: Blush, Champagne, Emerald and Gunmetal.
D’aire Silk Mask
Designed in patterns ranging from Camo to Midnight Stars, and solid colors such as Rouge, Black and Cocoa, D’aire silk face masks feature an adjustable nose bridge and adjustable ear loops, as well as a filter pocket. They’re available in three sizes: Small, Medium and Large. The masks can be machine washed with cold water on a delicate setting. D’aire also sells disposable filters that are custom molded to fit its silk face masks. Filters come in packs of 10 or 20.
Claire & Clara Washable Silk Face Mask
Claire & Clara’s silk face masks are constructed with two layers of fabric. They have adjustable elastic ear loops, too. The brand makes face milks with and without filter pockets. Silk masks come in five colors: Light Blue, Pink, White, Navy and Violet. Claire & Clara also sells a pack of five disposable filters.
Benefits of silk face masks
Guerra’s lab found that “silk face coverings repelled droplets in spray tests as well as disposable single-use surgical masks.” But silk face coverings have another advantage over surgical face masks: They can be cleaned and reused. Additionally, Guerra said silk has electrostatic properties, meaning it’s positively charged. When a face mask has an outer silk layer, small particles stick to it due to the positive charge — and those particles consequently don’t go through the fabric. Silk also has some antiviral and antibacterial properties given the copper found in it, Guerra noted.
Finally, silk is known to be good for your skin. Michele Farber, MD, a board-certified dermatologist at Schweiger Dermatology Group, recommended silk pillowcases for acne-prone and sensitive skin, as it does not result in as much friction — and therefore irritation — as other fabrics. That guidance can now be applied to face masks. Farber said silk also does not absorb as much oil and dirt compared to other types of fabric, nor does it strip as much moisture from skin.
How to double mask with a silk face mask
Based on his research, Guerra suggested double masking by layering a silk face mask over a disposable mask. The silk mask acts as a hydrophobic barrier — since wet masks are less effective, according to the CDC — and the combination provides you with multiple layers of protection.
Farber noted that double masking does not allow you to get the skin benefits of the silk mask. But she added that wearing a tightly woven, well-fitting, multi-layered silk mask with a filter is an acceptable alternative to double masking, depending on the situation. As for cleaning your silk face mask, Farber and Guerra said you typically can hand wash or machine wash them, though it ultimately depends on the brand’s specific instructions.
Guerra became curious about silk as a material for face masks when his wife, who is a physician, had to reuse her N95 mask for multiple days at the beginning of the pandemic. His lab, which usually studies cocoon construction by silk moth caterpillars, began researching which fabrics are most effective for frontline workers to double mask with in order to preserve their respirators, as well as which fabrics make effective reusable face masks for the general public.
During the research, Guerra’s lab examined the hydrophobicity of cotton, polyester and silk fabrics by measuring how well they repelled small aerosol water droplets. The lab also examined the breathability of the fabrics and how regular cleaning affected their ability to maintain hydrophobicity over time after being repetitively cleaned. Guerra said his lab decided against studying silk’s level of filtration — common in similar tests — because many other researchers were already working on testing silk fabric’s filtration capabilities.
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