Technical Requirements For Breathable Laminated Sheet

Composite film product is a structure that combines PE film and non-woven fabric with hot melt adhesive under the action of pressure. At present, manufacturers of related hygiene products mainly have the following technical requirements for breathable laminated sheets: high bonding strength, aging resistance, high softness, no rewet, low odor, and no fluorescence.

1. High bonding strength.

It generally refers to the peel strength that separates the PE film from the nonwoven. For example, comparing Nanbao products HM-840 and HM-838 with competing products, it can be concluded that the peel strength of Nanbao has reached 20g/in. under room temperature and low temperature conditions, and the peel strength of Nanbao HM-840 is higher than that of HM- 838 and competing products are 40% higher.

2. Anti-aging.

Aging resistance refers to whether the performance of the composite film product is still stable after half a year or one year. The laboratory generally simulates the aging condition according to the equivalent principle of room temperature. The aging condition is a temperature of 60°C and a relative humidity of 50%. For example, Nanbao's internal control standard is that after aging at 60°C for 6 days, the peel strength is required to decrease by <20% (the amount of glue applied is 1.0g/square meter). According to the equivalent principle at room temperature, aging at 60°C for 6 days is equivalent to aging a breathable laminated sheet at room temperature for one year.

Through experimental testing, it can be concluded that the aging performance of Nanbao HM-840, HM-838 and competing products are all qualified, and the drop in peel strength does not exceed 20%.

3. High softness.

With the improvement of people's consumption level, the comfort performance of sanitary products is getting more and more attention, so the composite film is required to be very soft. In addition to the soft base material, from the perspective of hot melt adhesive, the composite film has to be soft. The following requirements: first, the hot melt adhesive has good flexibility; second, under the premise of ensuring the bonding strength, the amount of glue applied should be small and the glue should be thin.

4. No back seepage.

Back seepage is the phenomenon that hot melt adhesive penetrates from the glued side of the nonwoven fabric to the other side, which will seriously affect the winding, unwinding and subsequent use of the breathable composite film. The phenomenon of back seepage is mainly caused by the factors of substrate, process and glue.

5. Low odor.

With the development of the hygiene products industry, especially the sales channels for infants and children, consumers have increasingly strict requirements on the smell of products. At present, some manufacturers have launched odorless products.

No fluorescence. The hot melt adhesive for breathable laminated sheet does not add fluorescent agents that may be harmful to health.