摘要 |
<p>A method and apparatus for impregnating a porous substrate (10) with foam comprising transporting the porous substrate (10) through a nip region (17) defined by a rotating foraminous drum (14) and a foam discharge head (12), the foam discharge head (12) comprising one or more discharge openings, where the transport of the porous substrate (10) through the nip region (17) causes the porous substrate (10) to be compressed as it passes the discharge openings, and supplying foam to the discharge head (12) with pressure sufficient to discharge foam through the discharge openings to impregnate the porous substrate (10). </p> |