When using hot melt adhesives for sanitary napkins, it is crucial to pay close attention to temperature control, bonding stability, and hygiene and safety to avoid affecting product quality and user experience due to improper processing.
Hot melt adhesives are mainly used in sanitary napkin production for laminating various layers and applying adhesive to the backing. Their performance directly impacts the product's user experience and safety.
Strictly control the heating temperature. The melting temperature of common hot melt adhesives is between 160℃ and 180℃. If the heating temperature is too high, the adhesive is prone to aging and yellowing, leading to decreased adhesion; if the temperature is too low, the adhesive is too sticky, easily causing self-adhesion, stringing, and even adhesive residue on underwear. Some new low-temperature hot melt adhesives can be used at 120℃ to 160℃, making them more suitable for heat-sensitive materials.
Ensure moderate peel strength. The adhesive backing needs to be "firmly bonded and easily peeled off": it must prevent displacement during use while avoiding residue. Current standards HG/T 3948-2007 and the upcoming HG/T 3948-2025 both set strict requirements for 180° peel strength to ensure the adhesive's stability under different climatic conditions. Excessively strong or weak adhesion will affect the user experience.
Preventing Adhesive Transfer and Contamination: Adhesive application should be even and neat, avoiding stringing or tailing, as these areas are most prone to adhesive transfer and contamination of equipment or product surfaces. Furthermore, the adhesive layer should not be too thick to avoid material waste and increased residue risk.
Focusing on Environmental and Hygiene Standards: Hot melt adhesives should comply with hygiene standards such as GB 15979-2002, ensuring the absence of pathogens and low total bacterial count. The new standard also strengthens the control of environmental indicators such as VOC emissions, heavy metals, and odor to protect user health.