The structure of the sanitary napkin can be divided into a surface layer, an absorbent core( super absorbent polymer ), and a bottom layer.
The surface layer is the part that is in direct contact with the skin. Its material is soft, and the surface weave and indentation can affect the reverse osmosis effect (dryness) of the sanitary napkin.
PE perforated membrane surface layer and cotton surface layer are the two most commonly used materials. PE surface layer with micro-porous design can make menstrual blood not easy to seep and make users feel dry, but the material is hard and some users will cause Allergic reactions; due to improved cotton absorbency design, and the availability of perforated and composite materials, the market share after 2001 is gradually higher than sanitary napkins with PE surface layers.
The inner layer is mainly composed of cotton, non-woven fabric, paper pulp, or a composite of high-molecular polymer and high-molecular polymer composite paper, used to absorb the outflow of menstrual blood. The design of the site is mainly used to prevent side leakage, because it will show an angle with the sanitary napkin body during use, and it is easier to have friction with the groin. Therefore, the soft sanitary napkin is more popular with women. The backing of sanitary napkins is impervious to material, which can retain menstrual blood in the sanitary napkins. In the 70s and 80s, self-adhesive adhesives were developed to facilitate the fixing of sanitary napkins on underpants.
According to the national standard, sanitary napkins can be divided into three categories from the surface material:
Dry mesh sanitary napkin
It refers to sanitary napkins made of various perforated films as raw materials in the surface layer of sanitary napkins, which are mainly polyethylene, commonly known as PE film.
Cotton soft sanitary napkin
It refers to sanitary napkins made of various non-woven fabrics on the surface layer of sanitary napkins, which are mainly polypropylene, commonly known as PP.
Cotton sanitary napkins.
It refers to sanitary napkins made of pure cotton material for the surface layer of sanitary napkins, which are mainly pure cotton non-woven fabrics.
Source: Organized from the Internet.