Hot melt adhesive plays a crucial role in the production process of sanitary napkins. It is primarily used to bond the various layers of the sanitary napkin, such as the surface layer, absorbent layer, and bottom layer, together to form a unified whole. Specifically, hot melt adhesive ensures a tight bond between the surface material and the absorbent layer, preventing liquid leakage; simultaneously, it firmly connects the absorbent layer and the bottom layer, ensuring that the sanitary napkin does not delaminate or deform during use. Furthermore, hot melt adhesive can also be used to bond the side wings of the sanitary napkin, ensuring a tight fit to the underwear and preventing side leakage.
The adhesive (approximately 60%) is used to bond the top layer (non-woven fabric), absorbent layer (superabsorbent polymer (SAP)), and bottom layer (PE leak-proof film) of the sanitary napkin, forming a stable basic structure for the product.
The backing adhesive (pressure-sensitive adhesive on the back) is applied to the bottom of the sanitary napkin to ensure it adheres firmly to the underwear, preventing shifting. It also requires moderate peel strength and anti-transfer properties to avoid staining clothing.
Elastic Band Glue (Elastic Component Fixing): Used to secure side elastic bands, improving fit and leak-proof performance. The glue must be soft, elastic, and not seep back onto the non-woven fabric surface.
Urine Indicator Adhesive (Special Functional Adhesive): A hot melt adhesive containing a pH indicator, used in diapers or adult incontinence products. It changes color from yellow to green upon contact with urine, indicating when to change the diaper.
Individual Packaging Sealing Adhesive: Used for heat-sealing individual sanitary napkin packaging to ensure airtightness and hygiene.