Typical Formulation Ingredients
Ingredient
Parts by weight
Tall-oil rosin ester (Unitack R100L from Union Camp)
SBS copolymer (Stereon 840A from Firestone
Mineral oil (Kaydol from Witco)
Nonionic surfactant (Atmer 688 from ICI)
Antioxidant (Irganox 1010 from Ciba-Geigy)
Resulting Properties
Hydrophilic hot melt adhesive compositions are suitable for a variety of applications, especially in nonwoven disposable articles. These are prepared by blending various adhesive components with a surfactant. The surfactant has a hydrophile-lipophile balance (HLB) number of less than 15, and is incorporated into the composition in an amount such that the resultant adhesive has a contact angle of 75° or less, and preferably less than about 40°.
A low contact angle is desirable so that water, urine or other water-based discharges, upon contacting a laminate bound together by the adhesive, wets out rather than beads up resulting in the fluid being directed away from the adhesive and towards an absorbent core of the disposable article.