Text/Meteor Polymer Milan only
The rapid spread of epidemic has caused a shortage of masks. The price of ordinary medical masks on market has risen from a few cents to 3-5 yuan per piece. On February 13, SAIC-GM-Wuling announced that first batch of masks produced by company had officially rolled off assembly line. It is understood that it took only 3 days from idea to produce masks to first batch of masks from assembly line, which once again refreshed Wuling Speed. Not only GM Wuling, but also BYD, Foxconn and many other companies have joined army of mask manufacturers.
Medical masks typically have a multilayer structure, commonly referred to as SMS structure. The multiple layers of masks we often talk about are not provided by national mask standard GB/T 32610. If it is a medical mask, it must be at least 3 layers, that is what we call SMS (2 layers S layer and 1 layer M layer) ), at moment, largest number of layers in China is 5 layers, that is, SMMMS (2 layers of S layers and 3 layers of M layers). It is not difficult to make a mask, but SMMMS fabric is more difficult to make, it is hundreds of millions of dollars.
SMS structure: single ply spunbond (S) on both sides and single or multi ply meltblown (M) in middle. The best material for meltblown is meltblown fabric.
The main material that provides filtering effect of viruses in mask is non-woven fabric of middle layer M, obtained by melt blown.
The "melt-blown fabric" is widely known as "heart" of masks. It has good filtering ability, protection, thermal insulation and oil absorption. It is an important raw material for production of medical surgical masks and N95 masks. The main raw material for melt blown fabric is polypropylene, which is an ultra-thin electrostatic fiber fabric with a fiber diameter of about 2 microns. Its diameter is only one-tenth that of outer fiber of mask, which is capable of effectively capturing dust. When virus-containing droplets approach melt-blown fabric, they are also electrostatically adsorbed to surface and cannot pass through. Therefore, it is a necessary raw material for production of filter masks. (If you don't know if your mask can protect against viruses, just see if mask has meltblown fabric in it. Generally, fake masks consist of three layers of spunbond (layer S), no meltblown layer ( M) layer , so it can't be anti-virus.)
Actually, all these three layers are non-woven fabrics, and raw material is polypropylene, but production process is different. Among them, fiber diameter of spunbond layer on inner and outer sides is relatively thick, about 20 microns; fiber diameter of meltblown layer in middle is only 2 microns, made of a polypropylene material called refractory. finger fiber, and meltblown fabric is relatively fragile, it can not be washed with water or sprayed with alcohol. Even if it gets wet and then dry, it will damage fibers and create loopholes. Viruses will also pass through loopholes, and mask will lose its protective ability . If there are too many layers of S spunbond, mask will be stiffer, and if there is too much meltblown layer M, it will be more difficult to breathe, so insulating effect of mask can be judged by difficulty of breathing through mask. The harder it is to breathe, better barrier effect. However, if M layer turns into a thin film, it will basically be impossible to breathe, virus will be blocked, and people will soon die, so this is also a technical problem. Therefore, if you want to recycle mask, it can not be steamed, baked at a high temperature or sprinkled with alcohol, it is best to hang it in a ventilated place.
Meltblown non-woven fabrics are relatively small in our country, and they are mainly used in production of masks, environmental protection materials, clothing, battery separators and other products. According to statistics of China Textile Industry Associationindustry, production process in production of nonwovens in China is mainly based on spunbond. In 2018, production volume of spunbond nonwovens amounted to 2.9712 million tons, accounting for 50.09% of total production of nonwovens. in sanitary materials and other fields, followed by acupuncture technology, which accounted for 22.96%, spunlace technology, which accounted for 10.83%, chemical bonding technology, which accounted for 6.61%, thermal bonding technology, which accounted for 5.43%, air laying technology accounting for 2.51%, melt blown process accounting for 0.90%, and wet process accounting for 0.66%.
Dawn Co., Ltd. share price. grew rapidly due to production of meltblown fabric
After outbreak of epidemic, demand for masks has skyrocketed, and domestic leaders in field of nonwovens have also rapidly expanded their meltblown nonwovens production capacity. It is estimated that current domestic production capacity of meltblown nonwovens has increased to around 100,000 tons. On Feb. 23, Shanghai Petrochemical Jinchang Company released two rolls of meltblown camouflage fabric made from newly developed special materials for sale. After testing, all indicators were in line with requirements. This marks success of company's urgent research and development of special materials for meltblown fabric for masks. After successful trial production, Shanghai Jinchang Petrochemical Company can produce 6 tons of special materials for blown mask fabric per day. medical masks per day.