| 摘要 |
A molding process for compression molding blanks from a polymerizable, thermosetting resinous composition in which pearlescent particulate materials are mixed: Upper and lower mold parts, at least one of which has mold cavities formed in it, are held in an open condition. The resinous composition is sandwiched between two sheets of a film material and is placed on the lower mold part. At least one of the layers of film material is stretchable. The mold parts are moved together until the upper mold part contacts, without applying pressure to, the top of the resinous composition. The mold parts are held at this semi-closed condition for a period of time at an elevated temperature, thereby causing the viscosity of the resinous composition to rise significantly. The mold parts are then moved to the fully closed condition at which molding pressure is applied to the resinous material, and the resinous composition is then forced into and shaped by the mold cavities in the mold parts. The resinous composition eventually polymerizes and the molded blanks are removed from the mold.
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