Process for molding an integral skin foam using an evacuated mold cavity
AssigneeToyoda Gosei Co., Ltd.
InventorsMichihiko Nakamura, Masanao Ishikake, Yukio Kawakita, Akira Mabuchi, Osamu Yamanaka
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Abstract
A process for molding a semi-rigid integral skin foam which comprising an integral skin having a low degree of foaming and a core having a high degree of foaming. The process includes evacuating a mold cavity to a pressure of from above 50 to 700 Torr; injecting, into the evacuated mold cavity, a polyurethane material which contains a polyol component and an isocyanate component with air bubbles introduced therein by air loading, in the substantial absence of a foaming agent; and foaming the material to fill the cavity.
Claims3
A process for molding a semi-rigid integral skin foam which comprises an integral skin having a low degree of foaming and a core having a high degree of foaming, comprising the steps of:
- evacuating a mold cavity to a pressure of from above 50 to 700 Torr;
- injecting into said mold cavity a polyurethane precursor material consisting essentially of a polyol component and an isocyanate component, and containing air bubbles introduced therein by air loading, said precursor material being substantially free of a foaming agent;
- allowing said precursor material to react, while foaming said precursor material so as to flow and fill said mold cavity and thereby form said integral skin foam;
- such that a core having a high degree of foaming is formed by expansion of said air bubbles absorbed in said precursor material, and an integral skin having a low degree of foaming is formed at a surface of said precursor material by debubbling said air bubbles.
Dependencies are inferred from the claim text.