Sanitary napkins is a kind of sanitary products used by women during menstruation. The main material of sanitary napkins are cotton, non-woven fabric, fluff pulp or polymer composite and polymer composite paper formed by cotton, non-woven fabric, fluff pulp material complex above. The side design is mainly used to prevent side leakage, and it is divided into surface layer, absorption core and bottom three layers from inside to outside.

According to the material, sanitary napkins is mainly divided into three types: dry mesh pad, soft cotton pad and pure cotton pad.

• Dry mesh surface sanitary napkins refer to sanitary napkin is made of various perforated membranes as raw materials. The main material is polyethylene, commonly known as PE film.
• Cotton soft sanitary napkins refer to sanitary napkins whose surface layer is made of various non-woven materials. The main material is polypropylene, commonly known as PP.
• Pure cotton sanitary napkins refer to sanitary napkins whose surface layer is made of pure cotton material, and the main material is pure cotton non-woven fabric.

According to specifications, sanitary napkins can be divided into three categories.

• The length (L) of Class 1 (commonly known as large size) is: 270mm, 280mm, 290mm, 300mm;Width (W) is 70mm, 80mm, the mass(G) of each piece is 11.0g, suitable for night use in female menstruation.
• The length of Class 2 (commonly known as medium size) is 210mm, 220mm, 230mm, Width is 60mm, 70mm, 80mm, the mass of each piece is 7.3g, suitable for daytime use in female menstruation.
• The length of Class 3 (commonly known as small size) is: 170mm, 180mm, 190mm.Width is: 60mm, 70mm, the mass of each piece is 3.0g or 5.5g, suitable for women to use before and after menstruation and daytime use.

Basic structure: Sanitary napkins mainly consist of a surface layer, an absorption core and a three-layer structure at the bottom. The materials of each layer are bonded with hot melt adhesive. The outermost layer (bottom layer) is nonwoven fabric, which is soft material. Inward is a layer of leak-proof film (made of waterproof paper or polyethylene film). Then inside is the toilet paper wrapped with fluff pulp with super absorbent resin, which constitutes a strong absorbent core, menstrual blood once infiltrated into this layer, will be firmly attached, not reverse or scattered. There is pressure sensitive tape (self adhesive) on the back of the sanitary napkin, which is lined with the release paper. When use, just remove the release paper and throw it away, and then put the tape on the underwear to prevent slipping.