| abstract |
A process for the production of an integral composite molded item including (i) a surface portion having a synthetic resin phase containing a fibrous reinforcing material, (ii) a core portion having the synthetic resin phase containing bubble-containing particles, and (iii) a separation layer positioned between the surface portion and the core portion, the process including the steps of: providing in a substantially sealed mold (1) a separation layer which does not substantially pass therethrough bubble-containing particles but which is capable of passing a synthetic resin or its precursor that is liquidized at the time of molding; (2) a synthetic resin or its precursor on either or both sides of the separation layer; (3) a fibrous reinforcing material between the separation layer and the mold, and (4) an aggregate of bubble-containing particles on the side of the separation layer opposite to the mold; causing volume expansion of the aggregate; causing the resin to flow through the separation layer to thoroughly disperse it between the separation layer, mold, and particles to fill any voids therebetween; and completing solidification of the resin to form the composite molded item. The type of the resin and the type of bubble-containing particles may be selected and combined differently. |