| 摘要 |
PURPOSE:To enable to manufacture easily and simply a high quality resin-foamed sheet which is superior in homogeneity, by making use of an aqueous medium as a foaming agent of the resin. CONSTITUTION:An aqueous medium is made to stick and hold by treating a resin compound C made of a porous collective lump, to which a thermoplastic powdery and granular material coated with a thermoplastic powdery and granular material A and partially buried hydrophillic solid microscopic powder B is fused partially, with the aqueous medium. The resin compound C is melted and kneaded in an extruding machine under pressed terms wherein evaporation of the aqueous medium is controlled and made to discharge through a die whose temperature is held within a range shown by an expression [wherein Tf = lowest temperature ( deg.C) for molten and flowing state of resin composite, Tm = melting and kneading temperature ( deg.C) of resin composite, Td = temperature ( deg.C) of die]. A manufacturing-directional foamed sheet D is obtained by a method wherein upon discharge both the surfaces of a sheet is cooled to the temperature lower than the lowest temperature for a molten and flowing state of the resin and taken off while it is being extended in the direction of manufacture, and widening of a width is performed by heating the same at the temperature of more than the lowest temperature for the molten and flowing state of said resin composite while the same is being foamed secondarily. |
