摘要 |
<p>Integrally bonded composite polyurethane foams substantially free from coalescence and with no discernable bond or interface layer when viewed at 50X magnification can be formed by wet casting a second foamed polyurethane composition onto a first wet cast foamed polyurethane composition and simultaneously curing the cast foams. In a preferred embodiment, one curable polyurethane composition forms a slow recovery foam and the other curable polyurethane composition forms a resilient foam.</p> |