| 摘要 |
Chemically reactive liquid components, comprising a polyol (A) and an isocyanate (B), are mixed with a CO2 blowing agent, into a mixer (14) at a pressure sufficient for maintaining the CO2 dissolved into the liquid mixture. The resulting liquid mixture is subsequently fed to a foam dispensing device (10), making the mixture to flow along a restricted flow-path (16; 24) comprising a pressure-drop slot (16A; 24A) which extends in the direction of the flow and is dimensioned to provide a back-pressure in the upstream mixture to maintain CO2 in a dissolved state. The pressure in the mixture is gradually reduced while it is flowing at laminar condition along the pressure-drop slot (16A; 24A), while nucleation and frothing are performed by generation turbulency and eddies in the mixture which is flowing along an exit portion (16B, 16C; 16D; 16E; 24B, 24C) of the path (16; 24) consisting of an extension of the pressure drop slot (16A; 24A).
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