摘要 |
<p>A cushion member 10 for a face mask comprises a water activated, hydrophilic, open cell foam. The foam is formed with a urethane prepolymer having a functionality of less than 2, the prepolymer being toluene diisocyanate prepolymer. The specific gravity of the cushion member 10 is between 0.1 and 0.2 with a durometer hardness of 5 to 2 on the Shore A scale. The average cell diameter is 0.020 to 0.127mm. The cushion member 10 is covered by a thin skin between 0.025 and 0.127mm thick of surgical latex, acrylic latex, PVC, urethane, plastisol, nitrile or latex. The foam is made by combining an aqueous mixture of water and surfactant with a urethane prepolymer for the hydrophilic polyurethane foam.</p> |