Now, mask factories in European and American countries are facing some pressure: on the one…
With the deepening and promotion of the 2019-nCoV prevention and control work, the demand for prevention and control raw materials such as face masks and protective clothing continues to grow, which has led to the demand for raw materials for production also continues to grow. At present, I have compiled the raw materials for the production of face masks and protective clothing, and categorized them for a brief introduction, for your reference.
Raw material for face mask production
Qualified raw materials for face masks are the first key to the mask production line, and unqualified raw materials will lead to all the processes that follow being a waste of time.
There are many kinds of masks, with different shapes and standards, which can be basically divided into two categories according to their uses: protective masks and medical masks. Regardless of which masks, the raw materials used are similar. The following is an example of medical masks and N95 masks that are more numerous on the market, specifying what conditions should be specific to the raw materials of qualified face masks.
For a good raw material of protective mask raw material, it should have the following three conditions, one is the mask and the wearer’s face sealed well and comfortable to wear, the second is high filtration efficiency, the third is low breathing resistance.
Although the structure and protection performance of ordinary medical face masks and N95 masks have certain differences, the main mask raw material of both is non-woven fabric made of polypropylene.
Medical surgical face masks are generally three-layer nonwoven structure, with the inner and outer layers being spunbond nonwoven for medical and hygiene purposes and the middle layer being meltblown nonwoven for filtration purposes. This three-layer structure is also known as SMS structure. For N95 protective masks, it can be understood that there are multiple layers of meltblown nonwoven structure, i.e. SMMMS structure.
The outer layer raw material of spunbond nonwoven prevents droplets, body fluids, etc. from entering the mouth and nose directly. The inner layer raw material of spunbond nonwoven absorbs moisture and is at the same time the last barrier between the virus and the respiratory tract.
The meltblown nonwoven in the middle has an ultra-fine fiber structure that prevents viruses, which are even finer particles, from entering. In addition to the mechanical filtration of particles, the fibers can also adsorb even smaller particles through molecular gravity and electrostatic effects. If you want to make medical face masks, you need the face raw materials list: polypropylene nonwovens, meltblown filter cloth, nose clip bar, and earrings, etc.
The SMS structure can prevent suspended particles and body fluids from entering the mouth and nose, but also has good ventilation, to ensure that the wearer’s normal breathing. With a good raw material of face mask, together with the scientific design of the mask structure, it constitutes an efficient and high-quality face mask.
The meltblown nonwoven fabric is an ultra-fine electrostatic fiber cloth that traps dust (droplets containing pneumonia virus are electrostatically adsorbed to the surface of the nonwoven fabric when they are near the meltblown nonwoven fabric and cannot be penetrated). If you want to know exactly how meltblown nonwovens filter viruses, check out this article: How does the antiviral face mask filter the 2019-nCoV? How to judge?
Raw materials for protective clothing production
Chinese national standard GB 19082-2009, “Medical disposable protective clothing technical requirements”, specifies the requirements of medical disposable protective clothing, test methods, marking, instructions for use, packaging, and storage. This standard applies to medical disposable protective clothing that provides barriers and protection against potentially infectious patient blood, body fluids, secretions, airborne particulate matter, etc. when medical personnel is exposed to them at work.
The European EN standard stipulates that chemical protective clothing must comply with the European standard for personal protective equipment (PPE) in the highest hazard protection, and “Ⅲ” category requirements, and defines six different types of protective clothing. Through the fabric performance test and the finished product comprehensive performance field test, the protective clothing into the following six categories.
Protective clothing type, EN standard
|Description||Protective clothing type, EN standard||Description|
|Type 1 EN 943-1/2||Airtight protective clothing||Type 4 EN 14605||Aerosol tightness protective clothing|
|Type 2 EN 942-1||Non-airtight protective clothing||Type 5 EN ISO 13982-1/2||Protective clothing against solid particles|
|Type 3 EN 14605||Liquid Tightness Protective Clothing||Type 6 EN 13034|| |
Mild chemical splash protection
The performance of other relevant standards is as follows.
EN 1149-1: Anti-static properties
EN 1073-2: Protection against radioactive particulate matter
EN 14126: Protection against infectious bacteria
EN 11612: Limited performance of protective clothing against flame spread
Medical protective clothing as a kind of protective clothing, mainly used for medical personnel to wear, not only to drain moisture and breathable, comfortable to wear, but also to protect medical personnel from viruses, bacteria and other pollutants in the course of diagnosis and treatment, to resist the invasion of water, alcohol, oil, and effective anti-static, and even prevent dust from entering.
What kind of raw material is the medical protective suit made of that can achieve such an effect?
Medical protective clothing can be divided into woven, non-woven, and composite materials according to the organizational structure of the fabric. Medical protective clothing can be divided into disposable use, limited-use, and reusable according to the service life. Medical protective clothing can be divided into finishing, coating, and laminating according to the processing composite technology.
Protective clothing has different properties due to the different raw materials used, and the following raw materials are used in several medical protective clothing currently being sold and developed in the market.
Polypropylene spunbond raw material
Polypropylene spunbond raw material is made by stretching polypropylene to form a filament, laying it into a mesh, and then bonding it into a nonwoven fabric. Polypropylene spunbond cloth can be treated with antibacterial and antistatic treatment and made into antibacterial protective clothing, antistatic protective clothing, etc.
Compared to traditional cotton protective clothing, polypropylene spunbond protective clothing is certainly a step forward. Because of its low price and disposable use, it can greatly reduce cross-contamination rates and has been heavily pushed abroad for a considerable period of time since its introduction. However, the raw material has a relatively low hydrostatic pressure and a poor barrier efficiency against viral particles, and can only be used as a general protective item such as sterile surgical gowns and sterile wraps.
Nonwovens made of polyester fiber and wood pulp
The raw material is a non-woven composite reinforced with polyester webs entangled with wood pulp paper using a hydroentanglement technique and is made from polyester staple and wood pulp fibers. The raw material is soft to the touch, close to traditional textiles, and can be treated by three anti (anti-alcohol, anti-blood, anti-oil) and antistatic, antibacterial, etc., can be disinfected with γ-rays, but its antistatic pressure is also relatively low, the barrier efficiency to viral particles is also poor, so it is not particularly ideal medical protective clothing raw materials.
Polypropylene spunbond-meltblown-spunbond composite nonwovens, i.e. SMS
The meltblown nonwovens are made by drawing a fine melt stream of polymer extruded from the die’s spinneret holes by means of a high speed hot air stream, from which microfine fibers are formed and collected on a curtain or roller and bonded to themselves.
The characteristics of meltblown nonwovens are fine fiber diameter, large specific surface area, fluffy, soft, good drape, low filtration resistance, high filtration efficiency, strong hydrostatic pressure resistance, but low strength, poor abrasion resistance, which to a considerable extent limits the development of its applications. The spunbond fiber threads are denser, and the web is made up of continuous filaments, whose break strength and elongation are much greater than meltblown cloth, which can precisely compensate for the shortcomings of meltblown cloth.
In addition, SMS nonwovens can be treated with triple resistance (anti-alcohol, anti-blood and anti-oil) and anti-static, anti-bacterial, and anti-aging treatments to suit different applications. This raw material has the following excellent properties.
1 Uniform and aesthetically pleasing appearance
2 High hydrostatic pressure resistance
3 Soft feel
4 Good breathability
5 Good filtering results
6 Strong acid and alkali resistance
High polymer coated raw materials
Polymer-coated raw materials are made by laminating ordinary fabrics with a special film through a lamination process. There are many types of coatings used for protective fabrics, including PVC, polyethylene, polychloroprene and various other synthetic rubbers.
This material is made of protective clothing, waterproof, barrier against bacterial particles is very good, can be reused, but the moisture permeability is poor, the large amount of human sweat can not be excreted, wearing comfort performance is poor. The use of rubber-coated fabrics for protective clothing during SARS was a last resort. The latest development at home and abroad is the use of microporous Teflon film and fabric composite to obtain waterproof and breathable function, but as a disposable product expensive.