In the special period of epidemic prevention and contro […]
In the special period of epidemic prevention and control, everyone is required to wear masks when they go out. Therefore, the demand for masks is very large now, and the demand in many places is in short supply. Everyone pays attention to distinguishing when buying masks. Meltblown masks can filter viruses, while inferior masks cannot isolate and block viruses. Meltblown cloth is the core material of masks.
Due to the need for the prevention and control of the new coronavirus pneumonia epidemic, the production capacity of masks across the country has been stepped up to recover, but in the face of a huge gap, the supply is still in short supply. The reason why the mask can not be manufactured with the mask machine is because the core material of the mask: meltblown cloth is lacking. In just one month, many companies have switched to producing masks. Although the price of melt blown cloth has increased greatly, the shortage of melt blown cloth across the country is severe. There is not so much melt blown cloth supply market, and now it is stuck in melt blown cloth. Link. Melt blown cloth, an important material for the production of medical surgical masks and N95 masks, is called the "heart" of the mask.
What is melt blown cloth:
Everyone cuts a regular medical surgical mask and you can see that this mask is composed of three layers, namely SMS structure:
1. The inner S layer is ordinary non-woven fabric, which is mainly hygroscopic;
2. The outer S layer is a non-woven fabric with waterproof treatment, which is mainly used to isolate the liquid sprayed by the patient and have the effect of preventing droplets.
3. The middle M layer uses an electret treated melt blown cloth, which can filter suspended bacterial particles and is the most important core layer.
The meltblown cloth is mainly made of polypropylene, and the fiber diameter can reach 1 to 5 microns. There are many voids, fluffy structure, and good wrinkle resistance. These ultrafine fibers with unique capillary structure increase the number and surface area of fibers per unit area, so that the meltblown cloth has good filtration, shielding, heat insulation and oil absorption. . It can be used in air, liquid filter materials, isolation materials, absorbent materials, mask materials, warmth-keeping materials, oil-absorbing materials and wipes.
Scope of application
(1) Medical and health cloths: surgical gowns, protective clothing, disinfection wraps, masks, diapers, sanitary napkins, etc.;
(2) Home decoration cloth: wall cloth, table cloth, bed sheet, bedspread, etc.;
(3) Follow-up cloth: lining, fusible lining, wadding, shaped cotton, various synthetic leather base cloth, etc.;
(4) Industrial cloth: filter material, insulating material, cement packaging bag, geotextile, covering cloth, etc.;
(5) Agricultural cloth: crop protection cloth, seedling raising cloth, irrigation cloth, thermal insulation curtain, etc.;
(6) Others: space cotton, thermal insulation materials, linoleum, cigarette filters, tea bags, etc.
The melt blown cloth filter material is randomly distributed and bonded together by polypropylene ultrafine fibers, and the appearance is white, flat and soft. The material fiber fineness is 0.5-1.0μm. The random distribution of fibers provides more thermal bonding between fibers. Opportunities, so that the melt blown gas filter material has a larger specific surface area, a higher porosity (≥75%). After high-pressure electret filtration efficiency, the product has the characteristics of low resistance, high efficiency and high dust capacity.
Non-woven fabric (English name: Non Woven Fabric or Nonwoven cloth), also known as non-woven fabric, is composed of directional or random fibers. It is called cloth because of its appearance and certain properties.
Non-woven fabric has the characteristics of moisture-proof, breathable, flexible, light weight, non-combustible, easy to decompose, non-toxic and non-irritating, rich in color, low price, and recyclable. For example, polypropylene (PP material) pellets are mostly used as raw materials, which are produced by continuous one-step method of high-temperature melting, spinning, laying, and hot-pressing.
Non-woven fabric characteristics
The non-woven fabric has no warp and weft threads, it is very convenient to cut and sew, and it is light and easy to shape, which is deeply loved by craft lovers.
Because it is a fabric that does not need to be spun and weaves, it just oriented or randomly arrange the textile short fibers or filaments to form a web structure, which is then reinforced by mechanical, thermal bonding or chemical methods.
It is not interwoven and knitted together one by one yarn, but the fibers are directly bonded together by physical methods, so when you get the sticky scale in your clothes, you will find that It is impossible to draw a single thread. Non-woven fabric breaks through the traditional textile principle, and has the characteristics of short process flow, fast production rate, high output, low cost, wide use, and multiple sources of raw materials.
The relationship between non-woven fabric and spunbond fabric
Spunbond fabric and non-woven fabric are subordinate. There are many production processes for the manufacture of non-woven fabrics, among which spunbond is one of the non-woven production processes (including spunbond, meltblown, hot rolling, and spunlace. Most of them are currently on the market. Non-woven fabric produced by spunbond method)
According to the composition of non-woven fabrics, there are polyester, polypropylene, nylon, spandex, acrylic, etc.; different compositions will have completely different styles of non-woven fabrics. The spunbond fabric usually refers to polyester spunbond and polypropylene spunbond; the styles of these two fabrics are very similar and can be distinguished by high temperature testing.
Non-woven fabric is a kind of non-woven fabric, which directly uses polymer chips, short fibers or filaments to form fibers through airflow or mechanical netting, and then undergo hydroentangling, needle punching, or hot rolling reinforcement, and finally finishing The resulting non-woven fabric. A new type of fiber product with soft, breathable and flat structure. The advantage is that it does not produce fiber debris, is strong, durable, and silky soft. It is also a kind of reinforcing material, and it has a cotton feel. Compared with cotton, non-woven The cloth bag is easy to form and cheap to manufacture.
1. Light weight: Polypropylene resin is used as the main raw material for production, with a specific gravity of only 0.9, which is only three-fifths of cotton. It is fluffy and has a good hand feeling.
2. Soft: It is composed of fine fibers (2-3D) and is formed by light-point hot-melt bonding. The finished product is moderately soft and comfortable.
3. Water repellency and breathability: Polypropylene slices do not absorb water, have zero moisture content, and have good water repellency. The 100% fiber composition is porous and has good air permeability. It is easy to keep the cloth dry and easy to wash.
4. Non-toxic and non-irritating: The product is produced with FDA food-grade raw materials, does not contain other chemical components, has stable performance, is non-toxic, non-odor, and does not irritate the skin.
5. Antibacterial and anti-chemical agents: Polypropylene is a chemically blunt substance, not moth-eaten, and can isolate the corrosion of bacteria and insects in the liquid; antibacterial, alkali corrosion, and the strength of the finished product will not be affected by erosion.
6. Antibacterial property. The product is water-repellent, not moldy, and can isolate the erosion of bacteria and insects in the liquid, and is not moldy.
7. Good physical properties. It is made of polypropylene spun silk directly spread into a net and thermally bonded. The strength of the product is better than that of ordinary staple fiber products. The strength is non-directional, and the strength is similar in the vertical and horizontal directions.
8. In terms of environmental protection, the raw material of most of the non-woven fabrics used is polypropylene, while the raw material of plastic bags is polyethylene. Although the names of the two substances are similar, their chemical structures are far apart. The chemical molecular structure of polyethylene is very stable and extremely difficult to decompose, so it takes 300 years for plastic bags to be decomposed; while the chemical structure of polypropylene is not strong, the molecular chain can easily be broken, which can be effectively degraded , And enter the next environmental cycle in a non-toxic form, a non-woven shopping bag can be completely decomposed within 90 days. Moreover, the non-woven shopping bag can be reused more than 10 times, and the pollution to the environment after being discarded is only 10% of the plastic bag.
1. Compared with woven fabric, the strength and durability are poor.
2. It cannot be cleaned like other fabrics.
3. The fibers are arranged in a certain direction, so it is easy to split from the right angle direction and so on. Therefore, the improvement of the production method mainly focuses on the improvement of preventing splitting.