The wide use of diapers and baby nappy has increasingly become a compulsory course for parents, and there are also great ways to choose and use them. In order to better understand the relevant procurement principles, we must first understand the raw materials, components and the role of each part - generally speaking, diapers are composed of four parts: surface layer, diversion layer, absorption core layer and bottom layer.
The surface layer is the part in direct contact with the human body and should be dry, comfortable and soft. The surface material needs to be fluffy, soft and hydrophilic, so as to ensure that the surface liquid can penetrate for many times, with fast penetration, less back penetration and high absorption rate, so that the liquid can contact the skin surface for a short time, dry and comfortable. In China, double-layer composite hot air nonwovens, medium embossed double-layer nonwovens, single-layer embossed hot air nonwovens and perforated hot air nonwovens are mainly used. The order of comfort of surface materials from good to bad is: cotton soft nonwovens, hot-air nonwovens and hot-rolled nonwovens.
The diversion layer is located between the surface layer and the absorption core layer. It is composed of special nonwoven materials and has the functions of rapid liquid capture, temporary liquid storage, diffusion and diversion, anti reverse osmosis, anti side leakage and so on. It can effectively help the liquid to quickly export from the surface layer and diffuse and distribute longitudinally, so that the liquid can quickly leave the user's skin and be evenly absorbed by the core layer. Therefore, diapers will not absorb liquid intensively, resulting in local thickening, which prevents subsequent urine from being absorbed by the super absorbent material Spa (super absorbent resin).
The absorbent core layer is the most important layer of diapers, which needs a lot of absorption. Water lock is strong, and its material is usually a mixture of fluff pulp and spa. Fluff pulp is an advanced absorbent pulp, which mainly plays a role similar to the conveying pipeline in the absorption core layer. Spa is a special polymer material, which can absorb hundreds to thousands of times of water. Under certain pressure, the absorbed water will not be squeezed out. Due to its large absorption, it not only reduces the amount of fluff pulp, but also greatly reduces the thickness of diapers. Thin 22 is more comfortable to wear, suitable for surface and shunting materials, coupled with a reasonable absorption core design can do this.
The main function of the bottom layer is to effectively prevent leakage. Its materials are breathable microporous membrane and composite bottom membrane. Microporous membrane increases the air permeability of the bottom layer, and materials with good air permeability are conducive to the discharge of water. The bottom material also needs good hydrostatic resistance to prevent liquid leakage. The hydrostatic pressure resistance of the bottom material is ranked from good to bad as follows: PE film, composite breathable cotton flexible bottom film, non-woven fabric / PE film composite film, PE perforated film and silk breathable film.
In short, the choice of diapers and baby nappy should be clean in appearance. Colorfast, leak proof bottom film intact, no hard block, no damage, etc., Soft feel and firm sealing; The elastic tape shall be bonded evenly, and the fixed bonding position shall meet the use requirements. During the permeability test, the substances in the built-in absorption layer shall not seep out in large quantities. On the premise of meeting the above performance and weight requirements.