At present, cotton masks, paper masks, activated carbon masks, sponge masks, medical surgical masks and N95 masks are available in the market. But only medical surgical masks and N95 masks can play a role in preventing infectious diseases.
The N95 mask is one of nine anti-particulate masks certified by NIOSH (National Institute of Occupational Safety and Health). "N" means unsuitable for oily particles (oil fume produced by cooking is oily particles, and droplets produced by people speaking or coughing are not oily); "95" means filtering under the test conditions specified by the NIOSH standard The efficiency reaches 95%. N95 is not a specific product name. As long as the product meets the N95 standard and passes the NIOSH review, it can be called a "N95 mask".
N95 mask: powerful 95% filtration efficiency
The N95 mask can filter most of the influenza virus, dust, pollen, smog, smoke and soot in automobile exhaust, and the filtering efficiency must be at least 95%.
N stands for not resistant to oil, and 95 stands for the level of filtration efficiency when tested with 0.3 micron particles. For the selection of masks, and the principle of protection, you can refer to this article: the types of masks, the principle of protection, and the method of distinguishing true and false
100x magnification to see mask meltblown cloth
After cutting the N95 mask, it can be seen that its internal structure mainly has three layers, and the key layer that plays a barrier role is the melt-blown cloth that has been fried on the market at 290,000 / ton.
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After magnifying the meltblown layer by 100 times, we observe the meltblown cloth, and we can see that the meltblown cloth is intersected by countless ultra-fine fibers to overlap into a dense network.
Among them, the thickness of each fiber is about 1 to 5 microns, and the fibers are intricately complex, which can prevent the entry of dust, viruses, and bacterial micro-foam, while maintaining the holes through which the breath passes. Meet the requirements of respiratory resistance.
There is no harm if there is no contrast. Take another non-woven fabric for comparison. Under the microscope, although the fibers look more uniform and beautiful, the diameter of the fibers is more than 20 microns, and the gap is much larger. Non-woven fabric effectively blocks viruses, bacteria and small particles of dust.
N95 Mask Cloth: Static Additive (Electret Treatment)
N95 mask melt-blown layer, the fiber density is not enough, but also need to increase static electricity, by performing an electret discharge treatment. In a certain range, the applied voltage (electret voltage), the larger the voltage, the more secure the charge is bound, and the higher the filtering efficiency.
The surface charge of the meltblown cloth will decay with time. After the electret masterbatch is added, the decay time is greatly prolonged. As the amount of the electret masterbatch is appropriately increased, the charge retention rate is also longer. Different formula decay rates.
The electret masterbatch (usually added 2-3%) separates the positive and negative charges of polypropylene ultrafine fibers and fixes them, so that the charges are stored for a longer time.
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Polarized fiber
There are very few electret masterbatch manufacturers, most of which are masterbatch plants for meltblown cloth, and their scale is usually not large.
Accumulated experience in long-term production. The formula has undergone a lot of exploratory tests from additives, base resin selection, granulation temperature, screw combination, melt index control, and additive content, etc., combined with electret treatment, optimized filtration performance, filtration resistance, etc. Index, the meltblown cloth is also placed for half a year, one year, two years or even longer and then test the filtration performance and other indicators.
Through the meltblown cloth factory and customer channels, we have collected electret masterbatch manufacturers with good feedback in the market for reference only. The specific application is also related to the manufacturer's meltblown equipment, process and formula.
Maintenance of N95 masks-natural enemies of static electricity
After the electret, the binding force weakens with the passage of time, the charges will migrate, and the polarization effect will weaken. As time goes by, static electricity will slowly disappear, which is why N95 masks have a shelf life. The general shelf life is about five years. N95 mask is most afraid of water, the secret of maintenance is to stay away from water.
In the process of N95 masks, particles are adsorbed and static electricity is consumed. Therefore, after a period of time, a large number of particles are adsorbed, and the static electricity is consumed. There is no additional static electricity to adsorb particles. This is why the used N95 masks cannot be reused.
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Finally, Yarn Fair reminds: It is precisely because of the intricacies of meltblown cloth fibers that N95 masks and medical surgical masks can block viruses and dust! Some criminals, in order to make huge profits, use extremely inferior, cheap, and substandard raw materials, and some even directly eliminate the most important meltblown filter layer in the middle and use ordinary non-woven fabrics instead.
Such a mask does not play a role in filtering viruses at all and may be harmful to the body. Therefore, when we purchase masks, we must pay attention to whether there are melt-blown cloths in the masks.
Source: Global Textile Network
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The Knitting Fair was informed that after cases have occurred in Madrid, Barcelona and Villarreal, the prices of local masks have risen exaggerated. The unit price of FFP2 masks sold in pharmacies has reached 300 euros.
Under strong demand, the price of masks in local online channels has also skyrocketed. The price of 60 packs of masks sold by Chinese sellers on the local Amazon website has reached 960 Euros. The price of 50 packs sold by sellers in Hong Kong, China has also reached 800 euros.
U.S .: Mask prices rise sharply
The United States currently has 30 million N95 medical masks in stock, but it is estimated that the United States needs 300 million masks, and there is still a gap of 270 million.
At present, major online e-commerce platforms such as Amazon have been out of stock, and offline pharmacies have also been out of stock. The reporter ran many offline pharmacies and couldn't buy masks. The American people interviewed by the reporter said that the price of local masks was too high. Outrageous, five $ 149, and many pharmacies are out of stock, so customers can't buy such a high price.
According to KHOU, a CBS-affiliated television station in the US, an N95 mask costs between $ 20 and $ 25 at the Holcombe Medical Device Store. The person in charge said that the price increase was due to a shortage of masks.
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Japan: Customers grab masks, disputes occur
According to the Japan Current Affairs Agency, with the spread of the new crown pneumonia epidemic, the supply of masks across Japan is seriously insufficient. Although Japanese mask manufacturers have tripled their production capacity, they still cannot meet the needs of the people.
At the entrance of many drugstores, people can be seen waiting in a long line to buy masks, and even some customers have disputes over buying masks.
On February 25, fighting at the entrance of a drug store in Yokohama, Kanagawa Prefecture, Japan, was triggered by grabbing a mask. On the same day, many people lined up before the drug store opened. According to the video shooter, it seemed that someone was going to cut in at the time, and there was an argument.
South Korea: No masks available
In Seoul, South Korea, there are long queues to buy masks. Although many people arrived early in the morning, they were unable to buy masks in the end. Some people had disputes with the shop assistants, and some people were crying. The epidemic situation continues to escalate, and the people's discoloration has caused "mask panic."
According to the Yonhap news agency, the 57-year-old Korean Kim turned to the post office and other public sales outlets in order to purchase a mask, but eventually found nothing. She cried with tears: "Yesterday I waited with my husband for more than an hour and did not buy a mask I'm so sad. I'm very weak in immunity, I'm taking immune medicine, and I don't have a lifeline-like mask. I'm very angry and depressed.
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French government announces: National masks requisitioned!
On March 4, the French government issued a decree requiring that all public legal persons and privately held and produced FFP2 (equivalent to domestic N95) respiratory protective masks and medical disposable masks be requisitioned by May 31.
Macron has released a message through social networks that "we will requisition all protective masks produced and stocked and distribute them to medical staff and French people infected with the new coronavirus". French Minister of Health Vélange said on the same day that France has now put 10 million medical masks into pharmacies across the country, and will use 15 to 20 million stock masks this week as the case may be. The French Minister of Economy and Finance Bruno Lemaire also said that France "has no supply problems and no risk of shortages".
However, protective products such as masks in French general pharmacies have long been out of stock, and some stock prices have increased several times. Recently, mask theft cases have occurred in hospitals in Nice, Marseille, Paris and other places.
Iran: Masks up 30 times
In Iran, masks are now expensive. The current price of masks is 330,000 Iranian rials, and a mask has risen 30 times. In addition, not only masks, many supermarkets in Deland have been sold out in the past two days.
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Italy: Masks up 100 times
The Italian "24 Hours of the Sun" reported that an Italian professional medical mask company specializing in the production of respiratory protection said that the company ran out of 10 years of mask inventory in 10 days and received orders for tens of millions of masks every day. Today, in the windows of many pharmacies in northern Italy, all they can see are posted notices-"masks sold out."
For some countries, the good news can be said to follow! China's meltblown cloth increased production, mask production capacity exceeded 100 million, effectively alleviating the market shortage!
At present, the price of non-woven fabrics for masks has skyrocketed. According to daily quotations, the price of meltblown non-woven fabrics purchased by some manufacturers has risen as high as 1233%.
Source: Global Textile Network
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