The role of medical protective clothing is to produce a bacterial barrier to prevent bacterial migration and reduce cross-infection. In recent years, some scientific research units and enterprises have developed many medical protective clothing, mostly with non-woven fabrics as the main fabric. Medical protective clothing can be divided into woven, non-woven and composite materials according to the structure of the fabric; according to the service life, it can be divided into disposable type (one-time use), limited-time type and reusable type; according to processing composite technology There are three types of methods: finishing, coating and laminating. As a medical protective film manufacturer, Jiangshan Jianlan Plastic Film Co., Ltd. brings you the air permeability principle of medical protective film.
The principle of air permeability of medical protective film is: Inorganic + stretching=micropores. In fact, the operation is very particular. Only micropores with suitable size and uniform distribution are effective. Insufficient stretching will result in excessive pore size. Small or even no pores, and poor stretching and undersized micropores can only be used as waste.
The film forming principle of breathable film: PE+CaCO3 (masterbatch)-film forming-stretching-breathable film. PE breathable film is blended with LDPE/LLDPE polyethylene resin carrier by adding about 50% of special calcium carbonate, and then oriented stretched to a certain ratio after being extruded into a film. Since polyethylene resin is a thermoplastic material, it can be stretched and crystallized under certain conditions. During stretching, the interface between the polymer and the calcium carbonate particles will be peeled off, and interconnected serpentine pores or pores are formed around the calcium carbonate particles. Channels, it is these pores and channels that give the film a breathable (wet) function, thereby communicating the environment on both sides of the film.
When the water vapor concentration on one side of the film is greater than the environment on the other side of the film, a humidity gradient pressure difference is formed. This provides the basic conditions for gas (vapor) convection. Due to the formation of convection, the humidity environment on both sides of the film tends to be relatively balanced. The breathable membrane is used as a water-proof membrane and has a barrier effect on liquids. Because there are many passages in the membrane, the tortuous channel formed by it has a large "L/D" value, which can be understood as a capillary. Therefore, under the same liquid (such as water) and the same pressure, as long as the height of the liquid column of the capillary is less than the length of the capillary, the liquid will not leak out.
The above is the air permeability principle of medical protective film brought by medical protective film manufacturers. I wonder if you all understand it? I am Jiangshan Jianlan Plastic Film Co., Ltd. I am looking forward to your consultation.