Discover which material is ideal in the making of cloth face masks

Some customers have asked us why do we use flannel in our face masks. Most find that flannel is soft on the skin and we agree, it is super soft on the skin, which offers a great level of confort even when wearing the mask for a long period of time if needed. But flannel has another characteristic that makes it well suited for the making of a cloth face mask.

Before we came up with our final concept of face mask, we made some investigation about which material(s) to use, which one would be most confortable but also which one would be most efficient in terms of filtering.

The reason that we chose flannel is that, while it is soft on the skin, it has been proven that cotton flannel when combined with another layer of tightly weaved cotton provides a high filter efficiency.

We share with you this study  https://pubs.acs.org/doi/full/10.1021/acsnano.0c03252.

The study states its purpose as follows:

• The use of cloth masks, many of them homemade, has become widely prevalent in response to the 2019–2020 SARS-CoV-2 outbreak, where the virus can be transmitted viarespiratory droplets. The use of such masks is also an anticipated response of the public in the face of future pandemics related to the respiratory tract. However, there is limited data available today on the performance of common cloth materials used in such cloth masks, particularly their filtration efficiencies as a function of different aerosol sizes ranging from ∼10 nm to ∼10 μm scale sizes. This is also of current significance as the relative effectiveness of different droplet sizes in transmitting the SARS-CoV-2 virus is not clear, and understanding the filtration response across a large bracketed size distribution is therefore important. In this paper, we report the results of experiments where we measure the filtration efficiencies of a number of common fabrics, as well as selective combinations for use as hybrid cloth masks, as a function of aerosol sizes ranging from ∼10 nm to 6 μ 

 It concludes that:

• “We find that cotton, natural silk, and chiffon can provide good protection, typically above 50% in the entire 10 nm to 6.0 μm range, provided they have a tight weave.”
• “Higher threads per inch cotton with tighter weaves resulted in better filtration efficiencies.”
• "we found that hybrid combinations of cloths such as high threads-per-inch cotton along with silk, chiffon, or flannel can provide broad filtration coverage across both the nanoscale (<300 nm) and micron scale (300 nm to 6 μm) range, likely due to the combined effects of electrostatic and physical filtering."

The combination "hybrid 3: cotton/flannel", illustrated in the table listing all the combinations tested during this research, has been identified as a top performer in terms of filter efficiency.

We therefore decided to use 2 layers of cotton, one external layer of tightly weaved cotton ("high threads-per-inch cotton) and one internal layer of cotton flannel. 

Be safe. Stay healthy.

To view our collection of face masks, please visit www.lagirafecouture.com